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, 2020 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 0.13.0 for #:nodelay.
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 0.13.0 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 status=progress
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 @cindex security, @command{guix pull}
3725 @cindex authenticity, of code obtained with @command{guix pull}
3726 Packages are installed or upgraded to the latest version available in
3727 the distribution currently available on your local machine. To update
3728 that distribution, along with the Guix tools, you must run @command{guix
3729 pull}: the command downloads the latest Guix source code and package
3730 descriptions, and deploys it. Source code is downloaded from a
3731 @uref{https://git-scm.com, Git} repository, by default the official
3732 GNU@tie{}Guix repository, though this can be customized. @command{guix
3733 pull} ensures that the code it downloads is @emph{authentic} by
3734 verifying that commits are signed by Guix developers.
3736 Specifically, @command{guix pull} downloads code from the @dfn{channels}
3737 (@pxref{Channels}) specified by one of the followings, in this order:
3741 the @option{--channels} option;
3743 the user's @file{~/.config/guix/channels.scm} file;
3745 the system-wide @file{/etc/guix/channels.scm} file;
3747 the built-in default channels specified in the @code{%default-channels}
3751 On completion, @command{guix package} will use packages and package
3752 versions from this just-retrieved copy of Guix. Not only that, but all
3753 the Guix commands and Scheme modules will also be taken from that latest
3754 version. New @command{guix} sub-commands added by the update also
3757 Any user can update their Guix copy using @command{guix pull}, and the
3758 effect is limited to the user who ran @command{guix pull}. For
3759 instance, when user @code{root} runs @command{guix pull}, this has no
3760 effect on the version of Guix that user @code{alice} sees, and vice
3763 The result of running @command{guix pull} is a @dfn{profile} available
3764 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3765 make sure to add it to the beginning of your search path so that you use
3766 the latest version, and similarly for the Info manual
3767 (@pxref{Documentation}):
3770 export PATH="$HOME/.config/guix/current/bin:$PATH"
3771 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3774 The @option{--list-generations} or @option{-l} option lists past generations
3775 produced by @command{guix pull}, along with details about their provenance:
3779 Generation 1 Jun 10 2018 00:18:18
3781 repository URL: https://git.savannah.gnu.org/git/guix.git
3782 branch: origin/master
3783 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3785 Generation 2 Jun 11 2018 11:02:49
3787 repository URL: https://git.savannah.gnu.org/git/guix.git
3788 branch: origin/master
3789 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3790 2 new packages: keepalived, libnfnetlink
3791 6 packages upgraded: emacs-nix-mode@@2.0.4,
3792 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3793 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3795 Generation 3 Jun 13 2018 23:31:07 (current)
3797 repository URL: https://git.savannah.gnu.org/git/guix.git
3798 branch: origin/master
3799 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3800 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3801 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3804 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3805 describe the current status of Guix.
3807 This @code{~/.config/guix/current} profile works exactly like the profiles
3808 created by @command{guix package} (@pxref{Invoking guix package}). That
3809 is, you can list generations, roll back to the previous
3810 generation---i.e., the previous Guix---and so on:
3813 $ guix pull --roll-back
3814 switched from generation 3 to 2
3815 $ guix pull --delete-generations=1
3816 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3819 You can also use @command{guix package} (@pxref{Invoking guix package})
3820 to manage the profile by naming it explicitly:
3822 $ guix package -p ~/.config/guix/current --roll-back
3823 switched from generation 3 to 2
3824 $ guix package -p ~/.config/guix/current --delete-generations=1
3825 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3828 The @command{guix pull} command is usually invoked with no arguments,
3829 but it supports the following options:
3832 @item --url=@var{url}
3833 @itemx --commit=@var{commit}
3834 @itemx --branch=@var{branch}
3835 Download code for the @code{guix} channel from the specified @var{url}, at the
3836 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3837 string), or @var{branch}.
3839 @cindex @file{channels.scm}, configuration file
3840 @cindex configuration file for channels
3841 These options are provided for convenience, but you can also specify your
3842 configuration in the @file{~/.config/guix/channels.scm} file or using the
3843 @option{--channels} option (see below).
3845 @item --channels=@var{file}
3846 @itemx -C @var{file}
3847 Read the list of channels from @var{file} instead of
3848 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
3849 @var{file} must contain Scheme code that
3850 evaluates to a list of channel objects. @xref{Channels}, for more
3853 @cindex channel news
3856 Display the list of packages added or upgraded since the previous
3857 generation, as well as, occasionally, news written by channel authors
3858 for their users (@pxref{Channels, Writing Channel News}).
3860 The package information is the same as displayed upon @command{guix
3861 pull} completion, but without ellipses; it is also similar to the output
3862 of @command{guix pull -l} for the last generation (see below).
3864 @item --list-generations[=@var{pattern}]
3865 @itemx -l [@var{pattern}]
3866 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3867 is provided, the subset of generations that match @var{pattern}.
3868 The syntax of @var{pattern} is the same as with @code{guix package
3869 --list-generations} (@pxref{Invoking guix package}).
3872 @cindex rolling back
3873 @cindex undoing transactions
3874 @cindex transactions, undoing
3875 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
3876 undo the last transaction.
3878 @item --switch-generation=@var{pattern}
3879 @itemx -S @var{pattern}
3881 Switch to a particular generation defined by @var{pattern}.
3883 @var{pattern} may be either a generation number or a number prefixed
3884 with ``+'' or ``-''. The latter means: move forward/backward by a
3885 specified number of generations. For example, if you want to return to
3886 the latest generation after @option{--roll-back}, use
3887 @option{--switch-generation=+1}.
3889 @item --delete-generations[=@var{pattern}]
3890 @itemx -d [@var{pattern}]
3891 When @var{pattern} is omitted, delete all generations except the current
3894 This command accepts the same patterns as @option{--list-generations}.
3895 When @var{pattern} is specified, delete the matching generations. When
3896 @var{pattern} specifies a duration, generations @emph{older} than the
3897 specified duration match. For instance, @option{--delete-generations=1m}
3898 deletes generations that are more than one month old.
3900 If the current generation matches, it is @emph{not} deleted.
3902 Note that deleting generations prevents rolling back to them.
3903 Consequently, this command must be used with care.
3905 @xref{Invoking guix describe}, for a way to display information about the
3906 current generation only.
3908 @item --profile=@var{profile}
3909 @itemx -p @var{profile}
3910 Use @var{profile} instead of @file{~/.config/guix/current}.
3914 Show which channel commit(s) would be used and what would be built or
3915 substituted but do not actually do it.
3917 @item --allow-downgrades
3918 Allow pulling older or unrelated revisions of channels than those
3921 @cindex downgrade attacks, protection against
3922 By default, @command{guix pull} protects against so-called ``downgrade
3923 attacks'' whereby the Git repository of a channel would be reset to an
3924 earlier or unrelated revision of itself, potentially leading you to
3925 install older, known-vulnerable versions of software packages.
3928 Make sure you understand its security implications before using
3929 @option{--allow-downgrades}.
3932 @item --disable-authentication
3933 Allow pulling channel code without authenticating it.
3935 @cindex authentication, of channel code
3936 By default, @command{guix pull} authenticates code downloaded from
3937 channels by verifying that its commits are signed by authorized
3938 developers, and raises an error if this is not the case. This option
3939 instructs it to not perform any such verification.
3942 Make sure you understand its security implications before using
3943 @option{--disable-authentication}.
3946 @item --system=@var{system}
3947 @itemx -s @var{system}
3948 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3949 the system type of the build host.
3952 Use the bootstrap Guile to build the latest Guix. This option is only
3953 useful to Guix developers.
3956 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3957 repository and branch to pull from, as well as @emph{additional} repositories
3958 containing package modules that should be deployed. @xref{Channels}, for more
3961 In addition, @command{guix pull} supports all the common build options
3962 (@pxref{Common Build Options}).
3968 @cindex @file{channels.scm}, configuration file
3969 @cindex configuration file for channels
3970 @cindex @command{guix pull}, configuration file
3971 @cindex configuration of @command{guix pull}
3972 Guix and its package collection are updated by running @command{guix pull}
3973 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3974 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3975 customized by defining @dfn{channels} in the
3976 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3977 of a Git repository to be deployed, and @command{guix pull} can be instructed
3978 to pull from one or more channels. In other words, channels can be used
3979 to @emph{customize} and to @emph{extend} Guix, as we will see below.
3980 Before that, some security considerations.
3982 @subsection Channel Authentication
3984 @anchor{channel-authentication}
3985 @cindex authentication, of channel code
3986 The @command{guix pull} and @command{guix time-machine} commands
3987 @dfn{authenticate} the code retrieved from channels: they make sure each
3988 commit that is fetched is signed by an authorized developer. The goal
3989 is to protect from unauthorized modifications to the channel that would
3990 lead users to run malicious code.
3992 As a user, you must provide a @dfn{channel introduction} in your
3993 channels file so that Guix knows how to authenticate its first commit.
3994 A channel specification, including its introduction, looks something
4000 (url "https://example.org/my-channel.git")
4002 (make-channel-introduction
4003 "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
4004 (openpgp-fingerprint
4005 "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
4008 The specification above shows the name and URL of the channel. The call
4009 to @code{make-channel-introduction} above specifies that authentication
4010 of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
4011 by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
4013 For the main channel, called @code{guix}, you automatically get that
4014 information from your Guix installation. For other channels, include
4015 the channel introduction provided by the channel authors in your
4016 @file{channels.scm} file. Make sure you retrieve the channel
4017 introduction from a trusted source since that is the root of your trust.
4019 If you're curious about the authentication mechanics, read on!
4021 @subsection Using a Custom Guix Channel
4023 The channel called @code{guix} specifies where Guix itself---its command-line
4024 tools as well as its package collection---should be downloaded. For instance,
4025 suppose you want to update from your own copy of the Guix repository at
4026 @code{example.org}, and specifically the @code{super-hacks} branch, you can
4027 write in @code{~/.config/guix/channels.scm} this specification:
4030 ;; Tell 'guix pull' to use my own repo.
4033 (url "https://example.org/my-guix.git")
4034 (branch "super-hacks")))
4038 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
4039 branch of the repository at @code{example.org}.
4041 @subsection Specifying Additional Channels
4043 @cindex extending the package collection (channels)
4044 @cindex personal packages (channels)
4045 @cindex channels, for personal packages
4046 You can also specify @emph{additional channels} to pull from. Let's say you
4047 have a bunch of custom package variants or personal packages that you think
4048 would make little sense to contribute to the Guix project, but would like to
4049 have these packages transparently available to you at the command line. You
4050 would first write modules containing those package definitions (@pxref{Package
4051 Modules}), maintain them in a Git repository, and then you and anyone else can
4052 use it as an additional channel to get packages from. Neat, no?
4054 @c What follows stems from discussions at
4055 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
4056 @c earlier discussions on guix-devel@gnu.org.
4058 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
4059 publish your personal channel to the world, we would like to share a few words
4064 Before publishing a channel, please consider contributing your package
4065 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
4066 to free software of all sorts, and packages in Guix proper are readily
4067 available to all Guix users and benefit from the project's quality assurance
4071 When you maintain package definitions outside Guix, we, Guix developers,
4072 consider that @emph{the compatibility burden is on you}. Remember that
4073 package modules and package definitions are just Scheme code that uses various
4074 programming interfaces (APIs). We want to remain free to change these APIs to
4075 keep improving Guix, possibly in ways that break your channel. We never
4076 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
4080 Corollary: if you're using an external channel and that channel breaks, please
4081 @emph{report the issue to the channel authors}, not to the Guix project.
4084 You've been warned! Having said this, we believe external channels are a
4085 practical way to exert your freedom to augment Guix' package collection and to
4086 share your improvements, which are basic tenets of
4087 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
4088 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
4091 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
4092 @command{guix pull} to pull from it @emph{in addition} to the default Guix
4095 @vindex %default-channels
4097 ;; Add my personal packages to those Guix provides.
4099 (name 'my-personal-packages)
4100 (url "https://example.org/personal-packages.git"))
4105 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
4106 add a channel the list of channels that the variable @code{%default-channels}
4107 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
4108 Manual}). With this file in place, @command{guix pull} builds not only Guix
4109 but also the package modules from your own repository. The result in
4110 @file{~/.config/guix/current} is the union of Guix with your own package
4114 $ guix pull --list-generations
4116 Generation 19 Aug 27 2018 16:20:48
4118 repository URL: https://git.savannah.gnu.org/git/guix.git
4120 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
4121 my-personal-packages dd3df5e
4122 repository URL: https://example.org/personal-packages.git
4124 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
4125 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
4126 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
4130 The output of @command{guix pull} above shows that Generation@tie{}19 includes
4131 both Guix and packages from the @code{my-personal-packages} channel. Among
4132 the new and upgraded packages that are listed, some like @code{my-gimp} and
4133 @code{my-emacs-with-cool-features} might come from
4134 @code{my-personal-packages}, while others come from the Guix default channel.
4136 To create a channel, create a Git repository containing your own package
4137 modules and make it available. The repository can contain anything, but a
4138 useful channel will contain Guile modules that export packages. Once you
4139 start using a channel, Guix will behave as if the root directory of that
4140 channel's Git repository has been added to the Guile load path (@pxref{Load
4141 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
4142 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
4143 module, then the module will be available under the name @code{(my-packages
4144 my-tools)}, and you will be able to use it like any other module
4145 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
4147 @cindex dependencies, channels
4148 @cindex meta-data, channels
4149 @subsection Declaring Channel Dependencies
4151 Channel authors may decide to augment a package collection provided by other
4152 channels. They can declare their channel to be dependent on other channels in
4153 a meta-data file @file{.guix-channel}, which is to be placed in the root of
4154 the channel repository.
4156 The meta-data file should contain a simple S-expression like this:
4163 (name some-collection)
4164 (url "https://example.org/first-collection.git")
4166 ;; The 'introduction' bit below is optional: you would
4167 ;; provide it for dependencies that can be authenticated.
4169 (channel-introduction
4171 (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
4172 (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
4174 (name some-other-collection)
4175 (url "https://example.org/second-collection.git")
4176 (branch "testing"))))
4179 In the above example this channel is declared to depend on two other channels,
4180 which will both be fetched automatically. The modules provided by the channel
4181 will be compiled in an environment where the modules of all these declared
4182 channels are available.
4184 For the sake of reliability and maintainability, you should avoid dependencies
4185 on channels that you don't control, and you should aim to keep the number of
4186 dependencies to a minimum.
4188 @cindex subdirectory, channels
4189 @subsection Package Modules in a Sub-directory
4191 As a channel author, you may want to keep your channel modules in a
4192 sub-directory. If your modules are in the sub-directory @file{guix}, you must
4193 add a meta-data file @file{.guix-channel} that contains:
4201 @cindex channel authorizations
4202 @subsection Specifying Channel Authorizations
4204 @anchor{channel-authorizations}
4205 As we saw above, Guix ensures the source code it pulls from channels
4206 comes from authorized developers. As a channel author, you need to
4207 specify the list of authorized developers in the
4208 @file{.guix-authorizations} file in the channel's Git repository. The
4209 authentication rule is simple: each commit must be signed by a key
4210 listed in the @file{.guix-authorizations} file of its parent
4211 commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
4212 (DAG). Each commit can have zero or more parents; ``regular'' commits
4213 have one parent and merge commits have two parent commits. Read
4214 @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
4215 for Computer Scientists}} for a great overview.} The
4216 @file{.guix-authorizations} file looks like this:
4219 ;; Example '.guix-authorizations' file.
4222 (version 0) ;current file format version
4224 (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
4226 ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
4228 ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
4232 Each fingerprint is followed by optional key/value pairs, as in the
4233 example above. Currently these key/value pairs are ignored.
4235 This authentication rule creates a chicken-and-egg issue: how do we
4236 authenticate the first commit? Related to that: how do we deal with
4237 channels whose repository history contains unsigned commits and lack
4238 @file{.guix-authorizations}? And how do we fork existing channels?
4240 @cindex channel introduction
4241 Channel introductions answer these questions by describing the first
4242 commit of a channel that should be authenticated. The first time a
4243 channel is fetched with @command{guix pull} or @command{guix
4244 time-machine}, the command looks up the introductory commit and verifies
4245 that it is signed by the specified OpenPGP key. From then on, it
4246 authenticates commits according to the rule above.
4248 Additionally, your channel must provide all the OpenPGP keys that were
4249 ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
4250 files, which can be either binary or ``ASCII-armored''. By default,
4251 those @file{.key} files are searched for in the branch named
4252 @code{keyring} but you can specify a different branch name in
4253 @code{.guix-channel} like so:
4258 (keyring-reference "my-keyring-branch"))
4261 To summarize, as the author of a channel, there are three things you have
4262 to do to allow users to authenticate your code:
4266 Export the OpenPGP keys of past and present committers with @command{gpg
4267 --export} and store them in @file{.key} files, by default in a branch
4268 named @code{keyring} (we recommend making it an @dfn{orphan branch}).
4271 Introduce an initial @file{.guix-authorizations} in the channel's
4272 repository. Do that in a signed commit (@pxref{Commit Access}, for
4273 information on how to sign Git commits.)
4276 Advertise the channel introduction, for instance on your channel's web
4277 page. The channel introduction, as we saw above, is the commit/key
4278 pair---i.e., the commit that introduced @file{.guix-authorizations}, and
4279 the fingerprint of the OpenPGP used to sign it.
4282 Before pushing to your public Git repository, you can run @command{guix
4283 git-authenticate} to verify that you did sign all the commits you are
4284 about to push with an authorized key:
4287 guix git authenticate @var{commit} @var{signer}
4291 where @var{commit} and @var{signer} are your channel introduction.
4292 @xref{Invoking guix git authenticate}, for details.
4294 Publishing a signed channel requires discipline: any mistake, such as an
4295 unsigned commit or a commit signed by an unauthorized key, will prevent
4296 users from pulling from your channel---well, that's the whole point of
4297 authentication! Pay attention to merges in particular: merge commits
4298 are considered authentic if and only if they are signed by a key present
4299 in the @file{.guix-authorizations} file of @emph{both} branches.
4301 @cindex primary URL, channels
4302 @subsection Primary URL
4304 Channel authors can indicate the primary URL of their channel's Git
4305 repository in the @file{.guix-channel} file, like so:
4310 (url "https://example.org/guix.git"))
4313 This allows @command{guix pull} to determine whether it is pulling code
4314 from a mirror of the channel; when that is the case, it warns the user
4315 that the mirror might be stale and displays the primary URL. That way,
4316 users cannot be tricked into fetching code from a stale mirror that does
4317 not receive security updates.
4319 This feature only makes sense for authenticated repositories, such as
4320 the official @code{guix} channel, for which @command{guix pull} ensures
4321 the code it fetches is authentic.
4323 @cindex news, for channels
4324 @subsection Writing Channel News
4326 Channel authors may occasionally want to communicate to their users
4327 information about important changes in the channel. You'd send them all
4328 an email, but that's not convenient.
4330 Instead, channels can provide a @dfn{news file}; when the channel users
4331 run @command{guix pull}, that news file is automatically read and
4332 @command{guix pull --news} can display the announcements that correspond
4333 to the new commits that have been pulled, if any.
4335 To do that, channel authors must first declare the name of the news file
4336 in their @file{.guix-channel} file:
4341 (news-file "etc/news.txt"))
4344 The news file itself, @file{etc/news.txt} in this example, must look
4345 something like this:
4350 (entry (tag "the-bug-fix")
4351 (title (en "Fixed terrible bug")
4353 (body (en "@@emph@{Good news@}! It's fixed!")
4354 (eo "Certe ĝi pli bone funkcias nun!")))
4355 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
4356 (title (en "Added a great package")
4357 (ca "Què vol dir guix?"))
4358 (body (en "Don't miss the @@code@{hello@} package!"))))
4361 While the news file is using the Scheme syntax, avoid naming it with a
4362 @file{.scm} extension or else it will get picked up when building the
4363 channel and yield an error since it is not a valid module.
4364 Alternatively, you can move the channel module to a subdirectory and
4365 store the news file in another directory.
4367 The file consists of a list of @dfn{news entries}. Each entry is
4368 associated with a commit or tag: it describes changes made in this
4369 commit, possibly in preceding commits as well. Users see entries only
4370 the first time they obtain the commit the entry refers to.
4372 The @code{title} field should be a one-line summary while @code{body}
4373 can be arbitrarily long, and both can contain Texinfo markup
4374 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
4375 a list of language tag/message tuples, which allows @command{guix pull}
4376 to display news in the language that corresponds to the user's locale.
4378 If you want to translate news using a gettext-based workflow, you can
4379 extract translatable strings with @command{xgettext} (@pxref{xgettext
4380 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
4381 you write news entries in English first, the command below creates a PO
4382 file containing the strings to translate:
4385 xgettext -o news.po -l scheme -ken etc/news.txt
4388 To sum up, yes, you could use your channel as a blog. But beware, this
4389 is @emph{not quite} what your users might expect.
4391 @subsection Replicating Guix
4393 @cindex pinning, channels
4394 @cindex replicating Guix
4395 @cindex reproducibility, of Guix
4396 The @command{guix pull --list-generations} output above shows precisely which
4397 commits were used to build this instance of Guix. We can thus replicate it,
4398 say, on another machine, by providing a channel specification in
4399 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
4402 ;; Deploy specific commits of my channels of interest.
4405 (url "https://git.savannah.gnu.org/git/guix.git")
4406 (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
4408 (name 'my-personal-packages)
4409 (url "https://example.org/personal-packages.git")
4410 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
4413 The @command{guix describe --format=channels} command can even generate this
4414 list of channels directly (@pxref{Invoking guix describe}). The resulting
4415 file can be used with the -C options of @command{guix pull}
4416 (@pxref{Invoking guix pull}) or @command{guix time-machine}
4417 (@pxref{Invoking guix time-machine}).
4419 At this point the two machines run the @emph{exact same Guix}, with access to
4420 the @emph{exact same packages}. The output of @command{guix build gimp} on
4421 one machine will be exactly the same, bit for bit, as the output of the same
4422 command on the other machine. It also means both machines have access to all
4423 the source code of Guix and, transitively, to all the source code of every
4426 This gives you super powers, allowing you to track the provenance of binary
4427 artifacts with very fine grain, and to reproduce software environments at
4428 will---some sort of ``meta reproducibility'' capabilities, if you will.
4429 @xref{Inferiors}, for another way to take advantage of these super powers.
4431 @node Invoking guix time-machine
4432 @section Invoking @command{guix time-machine}
4434 @cindex @command{guix time-machine}
4435 @cindex pinning, channels
4436 @cindex replicating Guix
4437 @cindex reproducibility, of Guix
4439 The @command{guix time-machine} command provides access to other
4440 revisions of Guix, for example to install older versions of packages,
4441 or to reproduce a computation in an identical environment. The revision
4442 of Guix to be used is defined by a commit or by a channel
4443 description file created by @command{guix describe}
4444 (@pxref{Invoking guix describe}).
4446 The general syntax is:
4449 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4452 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4453 @command{guix} command of the specified revision. The @var{options} that define
4454 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4457 @item --url=@var{url}
4458 @itemx --commit=@var{commit}
4459 @itemx --branch=@var{branch}
4460 Use the @code{guix} channel from the specified @var{url}, at the
4461 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4462 string), or @var{branch}.
4464 @item --channels=@var{file}
4465 @itemx -C @var{file}
4466 Read the list of channels from @var{file}. @var{file} must contain
4467 Scheme code that evaluates to a list of channel objects.
4468 @xref{Channels} for more information.
4471 As for @command{guix pull}, the absence of any options means that the
4472 the latest commit on the master branch will be used. The command
4475 guix time-machine -- build hello
4478 will thus build the package @code{hello} as defined in the master branch,
4479 which is in general a newer revision of Guix than you have installed.
4480 Time travel works in both directions!
4482 Note that @command{guix time-machine} can trigger builds of channels and
4483 their dependencies, and these are controlled by the standard build
4484 options (@pxref{Common Build Options}).
4489 @c TODO: Remove this once we're more confident about API stability.
4491 The functionality described here is a ``technology preview'' as of version
4492 @value{VERSION}. As such, the interface is subject to change.
4496 @cindex composition of Guix revisions
4497 Sometimes you might need to mix packages from the revision of Guix you're
4498 currently running with packages available in a different revision of Guix.
4499 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4500 revisions in arbitrary ways.
4502 @cindex inferior packages
4503 Technically, an ``inferior'' is essentially a separate Guix process connected
4504 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4505 @code{(guix inferior)} module allows you to create inferiors and to
4506 communicate with them. It also provides a high-level interface to browse and
4507 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4509 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4510 to interact with a separate revision of Guix. For example, let's assume you
4511 want to install in your profile the current @code{guile} package, along with
4512 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4513 because the newer @code{guile-json} has an incompatible API and you want to
4514 run your code against the old API@. To do that, you could write a manifest for
4515 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4516 manifest, you would create an inferior for that old Guix revision you care
4517 about, and you would look up the @code{guile-json} package in the inferior:
4520 (use-modules (guix inferior) (guix channels)
4521 (srfi srfi-1)) ;for 'first'
4524 ;; This is the old revision from which we want to
4525 ;; extract guile-json.
4528 (url "https://git.savannah.gnu.org/git/guix.git")
4530 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4533 ;; An inferior representing the above revision.
4534 (inferior-for-channels channels))
4536 ;; Now create a manifest with the current "guile" package
4537 ;; and the old "guile-json" package.
4539 (list (first (lookup-inferior-packages inferior "guile-json"))
4540 (specification->package "guile")))
4543 On its first run, @command{guix package --manifest} might have to build the
4544 channel you specified before it can create the inferior; subsequent runs will
4545 be much faster because the Guix revision will be cached.
4547 The @code{(guix inferior)} module provides the following procedures to open an
4550 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4551 [#:cache-directory] [#:ttl]
4552 Return an inferior for @var{channels}, a list of channels. Use the cache at
4553 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4554 This procedure opens a new connection to the build daemon.
4556 As a side effect, this procedure may build or substitute binaries for
4557 @var{channels}, which can take time.
4560 @deffn {Scheme Procedure} open-inferior @var{directory} @
4561 [#:command "bin/guix"]
4562 Open the inferior Guix in @var{directory}, running
4563 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4564 the inferior could not be launched.
4567 @cindex inferior packages
4568 The procedures listed below allow you to obtain and manipulate inferior
4571 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4572 Return the list of packages known to @var{inferior}.
4575 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4577 Return the sorted list of inferior packages matching @var{name} in
4578 @var{inferior}, with highest version numbers first. If @var{version} is true,
4579 return only packages with a version number prefixed by @var{version}.
4582 @deffn {Scheme Procedure} inferior-package? @var{obj}
4583 Return true if @var{obj} is an inferior package.
4586 @deffn {Scheme Procedure} inferior-package-name @var{package}
4587 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4588 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4589 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4590 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4591 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4592 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4593 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4594 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4595 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4596 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4597 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4598 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4599 These procedures are the counterpart of package record accessors
4600 (@pxref{package Reference}). Most of them work by querying the inferior
4601 @var{package} comes from, so the inferior must still be live when you call
4605 Inferior packages can be used transparently like any other package or
4606 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4607 transparently handled by the @code{packages->manifest} procedure, which is
4608 commonly use in manifests (@pxref{Invoking guix package, the
4609 @option{--manifest} option of @command{guix package}}). Thus you can insert
4610 an inferior package pretty much anywhere you would insert a regular package:
4611 in manifests, in the @code{packages} field of your @code{operating-system}
4612 declaration, and so on.
4614 @node Invoking guix describe
4615 @section Invoking @command{guix describe}
4617 @cindex reproducibility
4618 @cindex replicating Guix
4619 Often you may want to answer questions like: ``Which revision of Guix am I
4620 using?'' or ``Which channels am I using?'' This is useful information in many
4621 situations: if you want to @emph{replicate} an environment on a different
4622 machine or user account, if you want to report a bug or to determine what
4623 change in the channels you are using caused it, or if you want to record your
4624 system state for reproducibility purposes. The @command{guix describe}
4625 command answers these questions.
4627 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4628 displays the channel(s) that it was built from, including their repository URL
4629 and commit IDs (@pxref{Channels}):
4633 Generation 10 Sep 03 2018 17:32:44 (current)
4635 repository URL: https://git.savannah.gnu.org/git/guix.git
4637 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4640 If you're familiar with the Git version control system, this is similar in
4641 spirit to @command{git describe}; the output is also similar to that of
4642 @command{guix pull --list-generations}, but limited to the current generation
4643 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4644 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4645 information is all it takes to describe the revision of Guix you're using, and
4646 also to replicate it.
4648 To make it easier to replicate Guix, @command{guix describe} can also be asked
4649 to return a list of channels instead of the human-readable description above:
4652 $ guix describe -f channels
4655 (url "https://git.savannah.gnu.org/git/guix.git")
4657 "e0fa68c7718fffd33d81af415279d6ddb518f727")
4659 (make-channel-introduction
4660 "9edb3f66fd807b096b48283debdcddccfea34bad"
4661 (openpgp-fingerprint
4662 "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
4666 You can save this to a file and feed it to @command{guix pull -C} on some
4667 other machine or at a later point in time, which will instantiate @emph{this
4668 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4669 From there on, since you're able to deploy the same revision of Guix, you can
4670 just as well @emph{replicate a complete software environment}. We humbly
4671 think that this is @emph{awesome}, and we hope you'll like it too!
4673 The details of the options supported by @command{guix describe} are as
4677 @item --format=@var{format}
4678 @itemx -f @var{format}
4679 Produce output in the specified @var{format}, one of:
4683 produce human-readable output;
4685 produce a list of channel specifications that can be passed to @command{guix
4686 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4688 @item channels-sans-intro
4689 like @code{channels}, but omit the @code{introduction} field; use it to
4690 produce a channel specification suitable for Guix version 1.1.0 or
4691 earlier---the @code{introduction} field has to do with channel
4692 authentication (@pxref{Channels, Channel Authentication}) and is not
4693 supported by these older versions;
4696 produce a list of channel specifications in JSON format;
4698 produce a list of channel specifications in Recutils format.
4701 @item --list-formats
4702 Display available formats for @option{--format} option.
4704 @item --profile=@var{profile}
4705 @itemx -p @var{profile}
4706 Display information about @var{profile}.
4709 @node Invoking guix archive
4710 @section Invoking @command{guix archive}
4712 @cindex @command{guix archive}
4714 The @command{guix archive} command allows users to @dfn{export} files
4715 from the store into a single archive, and to later @dfn{import} them on
4716 a machine that runs Guix.
4717 In particular, it allows store files to be transferred from one machine
4718 to the store on another machine.
4721 If you're looking for a way to produce archives in a format suitable for
4722 tools other than Guix, @pxref{Invoking guix pack}.
4725 @cindex exporting store items
4726 To export store files as an archive to standard output, run:
4729 guix archive --export @var{options} @var{specifications}...
4732 @var{specifications} may be either store file names or package
4733 specifications, as for @command{guix package} (@pxref{Invoking guix
4734 package}). For instance, the following command creates an archive
4735 containing the @code{gui} output of the @code{git} package and the main
4736 output of @code{emacs}:
4739 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4742 If the specified packages are not built yet, @command{guix archive}
4743 automatically builds them. The build process may be controlled with the
4744 common build options (@pxref{Common Build Options}).
4746 To transfer the @code{emacs} package to a machine connected over SSH,
4750 guix archive --export -r emacs | ssh the-machine guix archive --import
4754 Similarly, a complete user profile may be transferred from one machine
4755 to another like this:
4758 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4759 ssh the-machine guix archive --import
4763 However, note that, in both examples, all of @code{emacs} and the
4764 profile as well as all of their dependencies are transferred (due to
4765 @option{-r}), regardless of what is already available in the store on
4766 the target machine. The @option{--missing} option can help figure out
4767 which items are missing from the target store. The @command{guix copy}
4768 command simplifies and optimizes this whole process, so this is probably
4769 what you should use in this case (@pxref{Invoking guix copy}).
4771 @cindex nar, archive format
4772 @cindex normalized archive (nar)
4773 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4774 comparable in spirit to `tar', but with differences
4775 that make it more appropriate for our purposes. First, rather than
4776 recording all Unix metadata for each file, the nar format only mentions
4777 the file type (regular, directory, or symbolic link); Unix permissions
4778 and owner/group are dismissed. Second, the order in which directory
4779 entries are stored always follows the order of file names according to
4780 the C locale collation order. This makes archive production fully
4783 When exporting, the daemon digitally signs the contents of the archive,
4784 and that digital signature is appended. When importing, the daemon
4785 verifies the signature and rejects the import in case of an invalid
4786 signature or if the signing key is not authorized.
4787 @c FIXME: Add xref to daemon doc about signatures.
4789 The main options are:
4793 Export the specified store files or packages (see below). Write the
4794 resulting archive to the standard output.
4796 Dependencies are @emph{not} included in the output, unless
4797 @option{--recursive} is passed.
4801 When combined with @option{--export}, this instructs @command{guix archive}
4802 to include dependencies of the given items in the archive. Thus, the
4803 resulting archive is self-contained: it contains the closure of the
4804 exported store items.
4807 Read an archive from the standard input, and import the files listed
4808 therein into the store. Abort if the archive has an invalid digital
4809 signature, or if it is signed by a public key not among the authorized
4810 keys (see @option{--authorize} below).
4813 Read a list of store file names from the standard input, one per line,
4814 and write on the standard output the subset of these files missing from
4817 @item --generate-key[=@var{parameters}]
4818 @cindex signing, archives
4819 Generate a new key pair for the daemon. This is a prerequisite before
4820 archives can be exported with @option{--export}. Note that this
4821 operation usually takes time, because it needs to gather enough entropy
4822 to generate the key pair.
4824 The generated key pair is typically stored under @file{/etc/guix}, in
4825 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4826 key, which must be kept secret). When @var{parameters} is omitted,
4827 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4828 versions before 1.6.0, it is a 4096-bit RSA key.
4829 Alternatively, @var{parameters} can specify
4830 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4831 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4832 Libgcrypt Reference Manual}).
4835 @cindex authorizing, archives
4836 Authorize imports signed by the public key passed on standard input.
4837 The public key must be in ``s-expression advanced format''---i.e., the
4838 same format as the @file{signing-key.pub} file.
4840 The list of authorized keys is kept in the human-editable file
4841 @file{/etc/guix/acl}. The file contains
4842 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4843 s-expressions''} and is structured as an access-control list in the
4844 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4847 @item --extract=@var{directory}
4848 @itemx -x @var{directory}
4849 Read a single-item archive as served by substitute servers
4850 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4851 low-level operation needed in only very narrow use cases; see below.
4853 For example, the following command extracts the substitute for Emacs
4854 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4858 https://@value{SUBSTITUTE-SERVER}/nar/gzip/@dots{}-emacs-24.5 \
4859 | gunzip | guix archive -x /tmp/emacs
4862 Single-item archives are different from multiple-item archives produced
4863 by @command{guix archive --export}; they contain a single store item,
4864 and they do @emph{not} embed a signature. Thus this operation does
4865 @emph{no} signature verification and its output should be considered
4868 The primary purpose of this operation is to facilitate inspection of
4869 archive contents coming from possibly untrusted substitute servers
4870 (@pxref{Invoking guix challenge}).
4874 Read a single-item archive as served by substitute servers
4875 (@pxref{Substitutes}) and print the list of files it contains, as in
4880 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4881 | lzip -d | guix archive -t
4887 @c *********************************************************************
4889 @chapter Development
4891 @cindex software development
4892 If you are a software developer, Guix provides tools that you should find
4893 helpful---independently of the language you're developing in. This is what
4894 this chapter is about.
4896 The @command{guix environment} command provides a convenient way to set up
4897 @dfn{development environments} containing all the dependencies and tools
4898 necessary to work on the software package of your choice. The @command{guix
4899 pack} command allows you to create @dfn{application bundles} that can be
4900 easily distributed to users who do not run Guix.
4903 * Invoking guix environment:: Setting up development environments.
4904 * Invoking guix pack:: Creating software bundles.
4905 * The GCC toolchain:: Working with languages supported by GCC.
4906 * Invoking guix git authenticate:: Authenticating Git repositories.
4909 @node Invoking guix environment
4910 @section Invoking @command{guix environment}
4912 @cindex reproducible build environments
4913 @cindex development environments
4914 @cindex @command{guix environment}
4915 @cindex environment, package build environment
4916 The purpose of @command{guix environment} is to assist hackers in
4917 creating reproducible development environments without polluting their
4918 package profile. The @command{guix environment} tool takes one or more
4919 packages, builds all of their inputs, and creates a shell
4920 environment to use them.
4922 The general syntax is:
4925 guix environment @var{options} @var{package}@dots{}
4928 The following example spawns a new shell set up for the development of
4932 guix environment guile
4935 If the needed dependencies are not built yet, @command{guix environment}
4936 automatically builds them. The environment of the new shell is an
4937 augmented version of the environment that @command{guix environment} was
4938 run in. It contains the necessary search paths for building the given
4939 package added to the existing environment variables. To create
4940 a ``pure'' environment, in which the original environment variables have
4941 been unset, use the @option{--pure} option@footnote{Users sometimes
4942 wrongfully augment environment variables such as @env{PATH} in their
4943 @file{~/.bashrc} file. As a consequence, when @command{guix
4944 environment} launches it, Bash may read @file{~/.bashrc}, thereby
4945 introducing ``impurities'' in these environment variables. It is an
4946 error to define such environment variables in @file{.bashrc}; instead,
4947 they should be defined in @file{.bash_profile}, which is sourced only by
4948 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
4949 Manual}, for details on Bash start-up files.}.
4951 @vindex GUIX_ENVIRONMENT
4952 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
4953 variable in the shell it spawns; its value is the file name of the
4954 profile of this environment. This allows users to, say, define a
4955 specific prompt for development environments in their @file{.bashrc}
4956 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4959 if [ -n "$GUIX_ENVIRONMENT" ]
4961 export PS1="\u@@\h \w [dev]\$ "
4966 ...@: or to browse the profile:
4969 $ ls "$GUIX_ENVIRONMENT/bin"
4972 Additionally, more than one package may be specified, in which case the
4973 union of the inputs for the given packages are used. For example, the
4974 command below spawns a shell where all of the dependencies of both Guile
4975 and Emacs are available:
4978 guix environment guile emacs
4981 Sometimes an interactive shell session is not desired. An arbitrary
4982 command may be invoked by placing the @code{--} token to separate the
4983 command from the rest of the arguments:
4986 guix environment guile -- make -j4
4989 In other situations, it is more convenient to specify the list of
4990 packages needed in the environment. For example, the following command
4991 runs @command{python} from an environment containing Python@tie{}2.7 and
4995 guix environment --ad-hoc python2-numpy python-2.7 -- python
4998 Furthermore, one might want the dependencies of a package and also some
4999 additional packages that are not build-time or runtime dependencies, but
5000 are useful when developing nonetheless. Because of this, the
5001 @option{--ad-hoc} flag is positional. Packages appearing before
5002 @option{--ad-hoc} are interpreted as packages whose dependencies will be
5003 added to the environment. Packages appearing after are interpreted as
5004 packages that will be added to the environment directly. For example,
5005 the following command creates a Guix development environment that
5006 additionally includes Git and strace:
5009 guix environment --pure guix --ad-hoc git strace
5013 Sometimes it is desirable to isolate the environment as much as
5014 possible, for maximal purity and reproducibility. In particular, when
5015 using Guix on a host distro that is not Guix System, it is desirable to
5016 prevent access to @file{/usr/bin} and other system-wide resources from
5017 the development environment. For example, the following command spawns
5018 a Guile REPL in a ``container'' where only the store and the current
5019 working directory are mounted:
5022 guix environment --ad-hoc --container guile -- guile
5026 The @option{--container} option requires Linux-libre 3.19 or newer.
5029 @cindex certificates
5030 Another typical use case for containers is to run security-sensitive
5031 applications such as a web browser. To run Eolie, we must expose and
5032 share some files and directories; we include @code{nss-certs} and expose
5033 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
5034 the @env{DISPLAY} environment variable since containerized graphical
5035 applications won't display without it.
5038 guix environment --preserve='^DISPLAY$' --container --network \
5039 --expose=/etc/machine-id \
5040 --expose=/etc/ssl/certs/ \
5041 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
5042 --ad-hoc eolie nss-certs dbus -- eolie
5045 The available options are summarized below.
5048 @item --root=@var{file}
5049 @itemx -r @var{file}
5050 @cindex persistent environment
5051 @cindex garbage collector root, for environments
5052 Make @var{file} a symlink to the profile for this environment, and
5053 register it as a garbage collector root.
5055 This is useful if you want to protect your environment from garbage
5056 collection, to make it ``persistent''.
5058 When this option is omitted, the environment is protected from garbage
5059 collection only for the duration of the @command{guix environment}
5060 session. This means that next time you recreate the same environment,
5061 you could have to rebuild or re-download packages. @xref{Invoking guix
5062 gc}, for more on GC roots.
5064 @item --expression=@var{expr}
5065 @itemx -e @var{expr}
5066 Create an environment for the package or list of packages that
5067 @var{expr} evaluates to.
5069 For example, running:
5072 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
5075 starts a shell with the environment for this specific variant of the
5081 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
5084 starts a shell with all the base system packages available.
5086 The above commands only use the default output of the given packages.
5087 To select other outputs, two element tuples can be specified:
5090 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
5093 @item --load=@var{file}
5094 @itemx -l @var{file}
5095 Create an environment for the package or list of packages that the code
5096 within @var{file} evaluates to.
5098 As an example, @var{file} might contain a definition like this
5099 (@pxref{Defining Packages}):
5102 @verbatiminclude environment-gdb.scm
5105 @item --manifest=@var{file}
5106 @itemx -m @var{file}
5107 Create an environment for the packages contained in the manifest object
5108 returned by the Scheme code in @var{file}. This option can be repeated
5109 several times, in which case the manifests are concatenated.
5111 This is similar to the same-named option in @command{guix package}
5112 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
5116 Include all specified packages in the resulting environment, as if an
5117 @i{ad hoc} package were defined with them as inputs. This option is
5118 useful for quickly creating an environment without having to write a
5119 package expression to contain the desired inputs.
5121 For instance, the command:
5124 guix environment --ad-hoc guile guile-sdl -- guile
5127 runs @command{guile} in an environment where Guile and Guile-SDL are
5130 Note that this example implicitly asks for the default output of
5131 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
5132 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
5133 of @code{glib} (@pxref{Packages with Multiple Outputs}).
5135 This option may be composed with the default behavior of @command{guix
5136 environment}. Packages appearing before @option{--ad-hoc} are
5137 interpreted as packages whose dependencies will be added to the
5138 environment, the default behavior. Packages appearing after are
5139 interpreted as packages that will be added to the environment directly.
5142 Unset existing environment variables when building the new environment, except
5143 those specified with @option{--preserve} (see below). This has the effect of
5144 creating an environment in which search paths only contain package inputs.
5146 @item --preserve=@var{regexp}
5147 @itemx -E @var{regexp}
5148 When used alongside @option{--pure}, preserve the environment variables
5149 matching @var{regexp}---in other words, put them on a ``white list'' of
5150 environment variables that must be preserved. This option can be repeated
5154 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
5158 This example runs @command{mpirun} in a context where the only environment
5159 variables defined are @env{PATH}, environment variables whose name starts
5160 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
5163 @item --search-paths
5164 Display the environment variable definitions that make up the
5167 @item --system=@var{system}
5168 @itemx -s @var{system}
5169 Attempt to build for @var{system}---e.g., @code{i686-linux}.
5174 Run @var{command} within an isolated container. The current working
5175 directory outside the container is mapped inside the container.
5176 Additionally, unless overridden with @option{--user}, a dummy home
5177 directory is created that matches the current user's home directory, and
5178 @file{/etc/passwd} is configured accordingly.
5180 The spawned process runs as the current user outside the container. Inside
5181 the container, it has the same UID and GID as the current user, unless
5182 @option{--user} is passed (see below).
5186 For containers, share the network namespace with the host system.
5187 Containers created without this flag only have access to the loopback
5190 @item --link-profile
5192 For containers, link the environment profile to @file{~/.guix-profile}
5193 within the container. This is equivalent to running the command
5194 @samp{ln -s $GUIX_ENVIRONMENT ~/.guix-profile} within the container.
5195 Linking will fail and abort the environment if the directory already
5196 exists, which will certainly be the case if @command{guix environment}
5197 was invoked in the user's home directory.
5199 Certain packages are configured to look in @file{~/.guix-profile} for
5200 configuration files and data;@footnote{For example, the
5201 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
5202 for additional fonts.} @option{--link-profile} allows these programs to
5203 behave as expected within the environment.
5205 @item --user=@var{user}
5206 @itemx -u @var{user}
5207 For containers, use the username @var{user} in place of the current
5208 user. The generated @file{/etc/passwd} entry within the container will
5209 contain the name @var{user}, the home directory will be
5210 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
5211 the UID and GID inside the container are 1000. @var{user}
5212 need not exist on the system.
5214 Additionally, any shared or exposed path (see @option{--share} and
5215 @option{--expose} respectively) whose target is within the current user's
5216 home directory will be remapped relative to @file{/home/USER}; this
5217 includes the automatic mapping of the current working directory.
5220 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
5222 guix environment --container --user=foo \
5223 --expose=$HOME/test \
5224 --expose=/tmp/target=$HOME/target
5227 While this will limit the leaking of user identity through home paths
5228 and each of the user fields, this is only one useful component of a
5229 broader privacy/anonymity solution---not one in and of itself.
5232 For containers, the default behavior is to share the current working
5233 directory with the isolated container and immediately change to that
5234 directory within the container. If this is undesirable,
5235 @option{--no-cwd} will cause the current working directory to @emph{not}
5236 be automatically shared and will change to the user's home directory
5237 within the container instead. See also @option{--user}.
5239 @item --expose=@var{source}[=@var{target}]
5240 @itemx --share=@var{source}[=@var{target}]
5241 For containers, @option{--expose} (resp. @option{--share}) exposes the
5242 file system @var{source} from the host system as the read-only
5243 (resp. writable) file system @var{target} within the container. If
5244 @var{target} is not specified, @var{source} is used as the target mount
5245 point in the container.
5247 The example below spawns a Guile REPL in a container in which the user's
5248 home directory is accessible read-only via the @file{/exchange}
5252 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
5257 @command{guix environment}
5258 also supports all of the common build options that @command{guix
5259 build} supports (@pxref{Common Build Options}) as well as package
5260 transformation options (@pxref{Package Transformation Options}).
5262 @node Invoking guix pack
5263 @section Invoking @command{guix pack}
5265 Occasionally you want to pass software to people who are not (yet!)
5266 lucky enough to be using Guix. You'd tell them to run @command{guix
5267 package -i @var{something}}, but that's not possible in this case. This
5268 is where @command{guix pack} comes in.
5271 If you are looking for ways to exchange binaries among machines that
5272 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5273 publish}, and @ref{Invoking guix archive}.
5278 @cindex application bundle
5279 @cindex software bundle
5280 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5281 @dfn{software bundle}: it creates a tarball or some other archive
5282 containing the binaries of the software you're interested in, and all
5283 its dependencies. The resulting archive can be used on any machine that
5284 does not have Guix, and people can run the exact same binaries as those
5285 you have with Guix. The pack itself is created in a bit-reproducible
5286 fashion, so anyone can verify that it really contains the build results
5287 that you pretend to be shipping.
5289 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5290 their dependencies, you can run:
5293 $ guix pack guile emacs geiser
5295 /gnu/store/@dots{}-pack.tar.gz
5298 The result here is a tarball containing a @file{/gnu/store} directory
5299 with all the relevant packages. The resulting tarball contains a
5300 @dfn{profile} with the three packages of interest; the profile is the
5301 same as would be created by @command{guix package -i}. It is this
5302 mechanism that is used to create Guix's own standalone binary tarball
5303 (@pxref{Binary Installation}).
5305 Users of this pack would have to run
5306 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5307 find inconvenient. To work around it, you can create, say, a
5308 @file{/opt/gnu/bin} symlink to the profile:
5311 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5315 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5317 @cindex relocatable binaries, with @command{guix pack}
5318 What if the recipient of your pack does not have root privileges on
5319 their machine, and thus cannot unpack it in the root file system? In
5320 that case, you will want to use the @option{--relocatable} option (see
5321 below). This option produces @dfn{relocatable binaries}, meaning they
5322 they can be placed anywhere in the file system hierarchy: in the example
5323 above, users can unpack your tarball in their home directory and
5324 directly run @file{./opt/gnu/bin/guile}.
5326 @cindex Docker, build an image with guix pack
5327 Alternatively, you can produce a pack in the Docker image format using
5328 the following command:
5331 guix pack -f docker -S /bin=bin guile guile-readline
5335 The result is a tarball that can be passed to the @command{docker load}
5336 command, followed by @code{docker run}:
5339 docker load < @var{file}
5340 docker run -ti guile-guile-readline /bin/guile
5344 where @var{file} is the image returned by @var{guix pack}, and
5345 @code{guile-guile-readline} is its ``image tag''. See the
5346 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5347 documentation} for more information.
5349 @cindex Singularity, build an image with guix pack
5350 @cindex SquashFS, build an image with guix pack
5351 Yet another option is to produce a SquashFS image with the following
5355 guix pack -f squashfs bash guile emacs geiser
5359 The result is a SquashFS file system image that can either be mounted or
5360 directly be used as a file system container image with the
5361 @uref{https://www.sylabs.io/docs/, Singularity container execution
5362 environment}, using commands like @command{singularity shell} or
5363 @command{singularity exec}.
5365 Several command-line options allow you to customize your pack:
5368 @item --format=@var{format}
5369 @itemx -f @var{format}
5370 Produce a pack in the given @var{format}.
5372 The available formats are:
5376 This is the default format. It produces a tarball containing all the
5377 specified binaries and symlinks.
5380 This produces a tarball that follows the
5381 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
5382 Docker Image Specification}. The ``repository name'' as it appears in
5383 the output of the @command{docker images} command is computed from
5384 package names passed on the command line or in the manifest file.
5387 This produces a SquashFS image containing all the specified binaries and
5388 symlinks, as well as empty mount points for virtual file systems like
5392 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
5393 For that reason, @command{guix pack -f squashfs} always implies @code{-S
5394 /bin=bin}. Thus, your @command{guix pack} invocation must always start
5395 with something like:
5398 guix pack -f squashfs bash @dots{}
5401 If you forget the @code{bash} (or similar) package, @command{singularity
5402 run} and @command{singularity exec} will fail with an unhelpful ``no
5403 such file or directory'' message.
5407 @cindex relocatable binaries
5410 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
5411 anywhere in the file system hierarchy and run from there.
5413 When this option is passed once, the resulting binaries require support for
5414 @dfn{user namespaces} in the kernel Linux; when passed
5415 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
5416 PRoot support, can be thought of as the abbreviation of ``Really
5417 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
5418 other techniques if user namespaces are unavailable, and essentially
5419 work anywhere---see below for the implications.
5421 For example, if you create a pack containing Bash with:
5424 guix pack -RR -S /mybin=bin bash
5428 ...@: you can copy that pack to a machine that lacks Guix, and from your
5429 home directory as a normal user, run:
5437 In that shell, if you type @code{ls /gnu/store}, you'll notice that
5438 @file{/gnu/store} shows up and contains all the dependencies of
5439 @code{bash}, even though the machine actually lacks @file{/gnu/store}
5440 altogether! That is probably the simplest way to deploy Guix-built
5441 software on a non-Guix machine.
5444 By default, relocatable binaries rely on the @dfn{user namespace} feature of
5445 the kernel Linux, which allows unprivileged users to mount or change root.
5446 Old versions of Linux did not support it, and some GNU/Linux distributions
5449 To produce relocatable binaries that work even in the absence of user
5450 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
5451 case, binaries will try user namespace support and fall back to another
5452 @dfn{execution engine} if user namespaces are not supported. The
5453 following execution engines are supported:
5457 Try user namespaces and fall back to PRoot if user namespaces are not
5458 supported (see below).
5461 Try user namespaces and fall back to Fakechroot if user namespaces are
5462 not supported (see below).
5465 Run the program through user namespaces and abort if they are not
5469 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
5470 provides the necessary
5471 support for file system virtualization. It achieves that by using the
5472 @code{ptrace} system call on the running program. This approach has the
5473 advantage to work without requiring special kernel support, but it incurs
5474 run-time overhead every time a system call is made.
5477 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
5478 Fakechroot} virtualizes file system accesses by intercepting calls to C
5479 library functions such as @code{open}, @code{stat}, @code{exec}, and so
5480 on. Unlike PRoot, it incurs very little overhead. However, it does not
5481 always work: for example, some file system accesses made from within the
5482 C library are not intercepted, and file system accesses made @i{via}
5483 direct syscalls are not intercepted either, leading to erratic behavior.
5486 @vindex GUIX_EXECUTION_ENGINE
5487 When running a wrapped program, you can explicitly request one of the
5488 execution engines listed above by setting the
5489 @code{GUIX_EXECUTION_ENGINE} environment variable accordingly.
5492 @cindex entry point, for Docker images
5493 @item --entry-point=@var{command}
5494 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
5495 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
5496 support it. @var{command} must be relative to the profile contained in the
5499 The entry point specifies the command that tools like @code{docker run} or
5500 @code{singularity run} automatically start by default. For example, you can
5504 guix pack -f docker --entry-point=bin/guile guile
5507 The resulting pack can easily be loaded and @code{docker run} with no extra
5508 arguments will spawn @code{bin/guile}:
5511 docker load -i pack.tar.gz
5512 docker run @var{image-id}
5515 @item --expression=@var{expr}
5516 @itemx -e @var{expr}
5517 Consider the package @var{expr} evaluates to.
5519 This has the same purpose as the same-named option in @command{guix
5520 build} (@pxref{Additional Build Options, @option{--expression} in
5521 @command{guix build}}).
5523 @item --manifest=@var{file}
5524 @itemx -m @var{file}
5525 Use the packages contained in the manifest object returned by the Scheme
5526 code in @var{file}. This option can be repeated several times, in which
5527 case the manifests are concatenated.
5529 This has a similar purpose as the same-named option in @command{guix
5530 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
5531 same manifest files. It allows you to define a collection of packages
5532 once and use it both for creating profiles and for creating archives
5533 for use on machines that do not have Guix installed. Note that you can
5534 specify @emph{either} a manifest file @emph{or} a list of packages,
5537 @item --system=@var{system}
5538 @itemx -s @var{system}
5539 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
5540 the system type of the build host.
5542 @item --target=@var{triplet}
5543 @cindex cross-compilation
5544 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
5545 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
5546 configuration triplets,, autoconf, Autoconf}).
5548 @item --compression=@var{tool}
5549 @itemx -C @var{tool}
5550 Compress the resulting tarball using @var{tool}---one of @code{gzip},
5551 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
5554 @item --symlink=@var{spec}
5555 @itemx -S @var{spec}
5556 Add the symlinks specified by @var{spec} to the pack. This option can
5557 appear several times.
5559 @var{spec} has the form @code{@var{source}=@var{target}}, where
5560 @var{source} is the symlink that will be created and @var{target} is the
5563 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
5564 symlink pointing to the @file{bin} sub-directory of the profile.
5566 @item --save-provenance
5567 Save provenance information for the packages passed on the command line.
5568 Provenance information includes the URL and commit of the channels in use
5571 Provenance information is saved in the
5572 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
5573 usual package metadata---the name and version of each package, their
5574 propagated inputs, and so on. It is useful information to the recipient of
5575 the pack, who then knows how the pack was (supposedly) obtained.
5577 This option is not enabled by default because, like timestamps, provenance
5578 information contributes nothing to the build process. In other words, there
5579 is an infinity of channel URLs and commit IDs that can lead to the same pack.
5580 Recording such ``silent'' metadata in the output thus potentially breaks the
5581 source-to-binary bitwise reproducibility property.
5583 @item --root=@var{file}
5584 @itemx -r @var{file}
5585 @cindex garbage collector root, for packs
5586 Make @var{file} a symlink to the resulting pack, and register it as a garbage
5589 @item --localstatedir
5590 @itemx --profile-name=@var{name}
5591 Include the ``local state directory'', @file{/var/guix}, in the resulting
5592 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
5593 profile---by default @var{name} is @code{guix-profile}, which corresponds to
5594 @file{~root/.guix-profile}.
5596 @file{/var/guix} contains the store database (@pxref{The Store}) as well
5597 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
5598 the pack means that the store is ``complete'' and manageable by Guix;
5599 not providing it pack means that the store is ``dead'': items cannot be
5600 added to it or removed from it after extraction of the pack.
5602 One use case for this is the Guix self-contained binary tarball
5603 (@pxref{Binary Installation}).
5607 Print the name of the derivation that builds the pack.
5610 Use the bootstrap binaries to build the pack. This option is only
5611 useful to Guix developers.
5614 In addition, @command{guix pack} supports all the common build options
5615 (@pxref{Common Build Options}) and all the package transformation
5616 options (@pxref{Package Transformation Options}).
5619 @node The GCC toolchain
5620 @section The GCC toolchain
5624 @cindex linker wrapper
5625 @cindex toolchain, for C development
5626 @cindex toolchain, for Fortran development
5628 If you need a complete toolchain for compiling and linking C or C++
5629 source code, use the @code{gcc-toolchain} package. This package
5630 provides a complete GCC toolchain for C/C++ development, including GCC
5631 itself, the GNU C Library (headers and binaries, plus debugging symbols
5632 in the @code{debug} output), Binutils, and a linker wrapper.
5634 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
5635 passed to the linker, add corresponding @code{-rpath} arguments, and
5636 invoke the actual linker with this new set of arguments. You can instruct the
5637 wrapper to refuse to link against libraries not in the store by setting the
5638 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
5640 The package @code{gfortran-toolchain} provides a complete GCC toolchain
5641 for Fortran development. For other languages, please use
5642 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
5645 @node Invoking guix git authenticate
5646 @section Invoking @command{guix git authenticate}
5648 The @command{guix git authenticate} command authenticates a Git checkout
5649 following the same rule as for channels (@pxref{channel-authentication,
5650 channel authentication}). That is, starting from a given commit, it
5651 ensures that all subsequent commits are signed by an OpenPGP key whose
5652 fingerprint appears in the @file{.guix-authorizations} file of its
5655 You will find this command useful if you maintain a channel. But in
5656 fact, this authentication mechanism is useful in a broader context, so
5657 you might want to use it for Git repositories that have nothing to do
5660 The general syntax is:
5663 guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
5666 By default, this command authenticates the Git checkout in the current
5667 directory; it outputs nothing and exits with exit code zero on success
5668 and non-zero on failure. @var{commit} above denotes the first commit
5669 where authentication takes place, and @var{signer} is the OpenPGP
5670 fingerprint of public key used to sign @var{commit}. Together, they
5671 form a ``channel introduction'' (@pxref{channel-authentication, channel
5672 introduction}). The options below allow you to fine-tune the process.
5675 @item --repository=@var{directory}
5676 @itemx -r @var{directory}
5677 Open the Git repository in @var{directory} instead of the current
5680 @item --keyring=@var{reference}
5681 @itemx -k @var{reference}
5682 Load OpenPGP keyring from @var{reference}, the reference of a branch
5683 such as @code{origin/keyring} or @code{my-keyring}. The branch must
5684 contain OpenPGP public keys in @file{.key} files, either in binary form
5685 or ``ASCII-armored''. By default the keyring is loaded from the branch
5686 named @code{keyring}.
5689 Display commit signing statistics upon completion.
5691 @item --cache-key=@var{key}
5692 Previously-authenticated commits are cached in a file under
5693 @file{~/.cache/guix/authentication}. This option forces the cache to be
5694 stored in file @var{key} in that directory.
5696 @item --historical-authorizations=@var{file}
5697 By default, any commit whose parent commit(s) lack the
5698 @file{.guix-authorizations} file is considered inauthentic. In
5699 contrast, this option considers the authorizations in @var{file} for any
5700 commit that lacks @file{.guix-authorizations}. The format of @var{file}
5701 is the same as that of @file{.guix-authorizations}
5702 (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
5706 @c *********************************************************************
5707 @node Programming Interface
5708 @chapter Programming Interface
5710 GNU Guix provides several Scheme programming interfaces (APIs) to
5711 define, build, and query packages. The first interface allows users to
5712 write high-level package definitions. These definitions refer to
5713 familiar packaging concepts, such as the name and version of a package,
5714 its build system, and its dependencies. These definitions can then be
5715 turned into concrete build actions.
5717 Build actions are performed by the Guix daemon, on behalf of users. In a
5718 standard setup, the daemon has write access to the store---the
5719 @file{/gnu/store} directory---whereas users do not. The recommended
5720 setup also has the daemon perform builds in chroots, under specific
5721 build users, to minimize interference with the rest of the system.
5724 Lower-level APIs are available to interact with the daemon and the
5725 store. To instruct the daemon to perform a build action, users actually
5726 provide it with a @dfn{derivation}. A derivation is a low-level
5727 representation of the build actions to be taken, and the environment in
5728 which they should occur---derivations are to package definitions what
5729 assembly is to C programs. The term ``derivation'' comes from the fact
5730 that build results @emph{derive} from them.
5732 This chapter describes all these APIs in turn, starting from high-level
5733 package definitions.
5736 * Package Modules:: Packages from the programmer's viewpoint.
5737 * Defining Packages:: Defining new packages.
5738 * Build Systems:: Specifying how packages are built.
5739 * The Store:: Manipulating the package store.
5740 * Derivations:: Low-level interface to package derivations.
5741 * The Store Monad:: Purely functional interface to the store.
5742 * G-Expressions:: Manipulating build expressions.
5743 * Invoking guix repl:: Programming Guix in Guile
5746 @node Package Modules
5747 @section Package Modules
5749 From a programming viewpoint, the package definitions of the
5750 GNU distribution are provided by Guile modules in the @code{(gnu packages
5751 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5752 packages @dots{})} module name space are not necessarily ``GNU
5753 packages''. This module naming scheme follows the usual Guile module
5754 naming convention: @code{gnu} means that these modules are distributed
5755 as part of the GNU system, and @code{packages} identifies modules that
5756 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5757 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5758 module exports a variable named @code{emacs}, which is bound to a
5759 @code{<package>} object (@pxref{Defining Packages}).
5761 The @code{(gnu packages @dots{})} module name space is
5762 automatically scanned for packages by the command-line tools. For
5763 instance, when running @code{guix install emacs}, all the @code{(gnu
5764 packages @dots{})} modules are scanned until one that exports a package
5765 object whose name is @code{emacs} is found. This package search
5766 facility is implemented in the @code{(gnu packages)} module.
5768 @cindex customization, of packages
5769 @cindex package module search path
5770 Users can store package definitions in modules with different
5771 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5772 name and module name must match. For instance, the @code{(my-packages
5773 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5774 relative to the load path specified with @option{--load-path} or
5775 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5776 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5777 these package definitions visible to the user interfaces:
5781 By adding the directory containing your package modules to the search path
5782 with the @code{-L} flag of @command{guix package} and other commands
5783 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
5784 environment variable described below.
5787 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5788 pulls from it. A channel is essentially a Git repository containing package
5789 modules. @xref{Channels}, for more information on how to define and use
5793 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5795 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5796 This is a colon-separated list of directories to search for additional
5797 package modules. Directories listed in this variable take precedence
5798 over the own modules of the distribution.
5801 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5802 each package is built based solely on other packages in the
5803 distribution. The root of this dependency graph is a small set of
5804 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5805 bootstrap)} module. For more information on bootstrapping,
5806 @pxref{Bootstrapping}.
5808 @node Defining Packages
5809 @section Defining Packages
5811 The high-level interface to package definitions is implemented in the
5812 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5813 example, the package definition, or @dfn{recipe}, for the GNU Hello
5814 package looks like this:
5817 (define-module (gnu packages hello)
5818 #:use-module (guix packages)
5819 #:use-module (guix download)
5820 #:use-module (guix build-system gnu)
5821 #:use-module (guix licenses)
5822 #:use-module (gnu packages gawk))
5824 (define-public hello
5830 (uri (string-append "mirror://gnu/hello/hello-" version
5834 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5835 (build-system gnu-build-system)
5836 (arguments '(#:configure-flags '("--enable-silent-rules")))
5837 (inputs `(("gawk" ,gawk)))
5838 (synopsis "Hello, GNU world: An example GNU package")
5839 (description "Guess what GNU Hello prints!")
5840 (home-page "https://www.gnu.org/software/hello/")
5845 Without being a Scheme expert, the reader may have guessed the meaning
5846 of the various fields here. This expression binds the variable
5847 @code{hello} to a @code{<package>} object, which is essentially a record
5848 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5849 This package object can be inspected using procedures found in the
5850 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5851 returns---surprise!---@code{"hello"}.
5853 With luck, you may be able to import part or all of the definition of
5854 the package you are interested in from another repository, using the
5855 @code{guix import} command (@pxref{Invoking guix import}).
5857 In the example above, @var{hello} is defined in a module of its own,
5858 @code{(gnu packages hello)}. Technically, this is not strictly
5859 necessary, but it is convenient to do so: all the packages defined in
5860 modules under @code{(gnu packages @dots{})} are automatically known to
5861 the command-line tools (@pxref{Package Modules}).
5863 There are a few points worth noting in the above package definition:
5867 The @code{source} field of the package is an @code{<origin>} object
5868 (@pxref{origin Reference}, for the complete reference).
5869 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5870 meaning that the source is a file to be downloaded over FTP or HTTP.
5872 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5873 the GNU mirrors defined in @code{(guix download)}.
5875 The @code{sha256} field specifies the expected SHA256 hash of the file
5876 being downloaded. It is mandatory, and allows Guix to check the
5877 integrity of the file. The @code{(base32 @dots{})} form introduces the
5878 base32 representation of the hash. You can obtain this information with
5879 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5880 hash} (@pxref{Invoking guix hash}).
5883 When needed, the @code{origin} form can also have a @code{patches} field
5884 listing patches to be applied, and a @code{snippet} field giving a
5885 Scheme expression to modify the source code.
5888 @cindex GNU Build System
5889 The @code{build-system} field specifies the procedure to build the
5890 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5891 represents the familiar GNU Build System, where packages may be
5892 configured, built, and installed with the usual @code{./configure &&
5893 make && make check && make install} command sequence.
5896 The @code{arguments} field specifies options for the build system
5897 (@pxref{Build Systems}). Here it is interpreted by
5898 @var{gnu-build-system} as a request run @file{configure} with the
5899 @option{--enable-silent-rules} flag.
5905 What about these quote (@code{'}) characters? They are Scheme syntax to
5906 introduce a literal list; @code{'} is synonymous with @code{quote}.
5907 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5908 for details. Here the value of the @code{arguments} field is a list of
5909 arguments passed to the build system down the road, as with @code{apply}
5910 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5913 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5914 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5915 @code{#:configure-flags} is a keyword used to pass a keyword argument
5916 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5920 The @code{inputs} field specifies inputs to the build process---i.e.,
5921 build-time or run-time dependencies of the package. Here, we define an
5922 input called @code{"gawk"} whose value is that of the @var{gawk}
5923 variable; @var{gawk} is itself bound to a @code{<package>} object.
5925 @cindex backquote (quasiquote)
5928 @cindex comma (unquote)
5932 @findex unquote-splicing
5933 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5934 us to introduce a literal list in the @code{inputs} field, while
5935 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5936 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5939 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5940 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5941 of ensuring that they are present (@pxref{Build Systems}).
5943 However, any other dependencies need to be specified in the
5944 @code{inputs} field. Any dependency not specified here will simply be
5945 unavailable to the build process, possibly leading to a build failure.
5948 @xref{package Reference}, for a full description of possible fields.
5950 Once a package definition is in place, the
5951 package may actually be built using the @code{guix build} command-line
5952 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5953 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5954 package definition using the @command{guix edit} command
5955 (@pxref{Invoking guix edit}).
5956 @xref{Packaging Guidelines}, for
5957 more information on how to test package definitions, and
5958 @ref{Invoking guix lint}, for information on how to check a definition
5959 for style conformance.
5960 @vindex GUIX_PACKAGE_PATH
5961 Lastly, @pxref{Channels}, for information
5962 on how to extend the distribution by adding your own package definitions
5965 Finally, updating the package definition to a new upstream version
5966 can be partly automated by the @command{guix refresh} command
5967 (@pxref{Invoking guix refresh}).
5969 Behind the scenes, a derivation corresponding to the @code{<package>}
5970 object is first computed by the @code{package-derivation} procedure.
5971 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
5972 The build actions it prescribes may then be realized by using the
5973 @code{build-derivations} procedure (@pxref{The Store}).
5975 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5976 Return the @code{<derivation>} object of @var{package} for @var{system}
5977 (@pxref{Derivations}).
5979 @var{package} must be a valid @code{<package>} object, and @var{system}
5980 must be a string denoting the target system type---e.g.,
5981 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5982 must be a connection to the daemon, which operates on the store
5983 (@pxref{The Store}).
5987 @cindex cross-compilation
5988 Similarly, it is possible to compute a derivation that cross-builds a
5989 package for some other system:
5991 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5992 @var{package} @var{target} [@var{system}]
5993 Return the @code{<derivation>} object of @var{package} cross-built from
5994 @var{system} to @var{target}.
5996 @var{target} must be a valid GNU triplet denoting the target hardware
5997 and operating system, such as @code{"aarch64-linux-gnu"}
5998 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
6001 @cindex package transformations
6002 @cindex input rewriting
6003 @cindex dependency tree rewriting
6004 Packages can be manipulated in arbitrary ways. An example of a useful
6005 transformation is @dfn{input rewriting}, whereby the dependency tree of
6006 a package is rewritten by replacing specific inputs by others:
6008 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
6009 [@var{rewrite-name}]
6010 Return a procedure that, when passed a package, replaces its direct and
6011 indirect dependencies (but not its implicit inputs) according to
6012 @var{replacements}. @var{replacements} is a list of package pairs; the
6013 first element of each pair is the package to replace, and the second one
6016 Optionally, @var{rewrite-name} is a one-argument procedure that takes
6017 the name of a package and returns its new name after rewrite.
6021 Consider this example:
6024 (define libressl-instead-of-openssl
6025 ;; This is a procedure to replace OPENSSL by LIBRESSL,
6027 (package-input-rewriting `((,openssl . ,libressl))))
6029 (define git-with-libressl
6030 (libressl-instead-of-openssl git))
6034 Here we first define a rewriting procedure that replaces @var{openssl}
6035 with @var{libressl}. Then we use it to define a @dfn{variant} of the
6036 @var{git} package that uses @var{libressl} instead of @var{openssl}.
6037 This is exactly what the @option{--with-input} command-line option does
6038 (@pxref{Package Transformation Options, @option{--with-input}}).
6040 The following variant of @code{package-input-rewriting} can match packages to
6041 be replaced by name rather than by identity.
6043 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
6044 Return a procedure that, given a package, applies the given @var{replacements} to
6045 all the package graph (excluding implicit inputs). @var{replacements} is a list of
6046 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
6047 @code{"guile@@2"}, and each procedure takes a matching package and returns a
6048 replacement for that package.
6051 The example above could be rewritten this way:
6054 (define libressl-instead-of-openssl
6055 ;; Replace all the packages called "openssl" with LibreSSL.
6056 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
6059 The key difference here is that, this time, packages are matched by spec and
6060 not by identity. In other words, any package in the graph that is called
6061 @code{openssl} will be replaced.
6063 A more generic procedure to rewrite a package dependency graph is
6064 @code{package-mapping}: it supports arbitrary changes to nodes in the
6067 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
6068 Return a procedure that, given a package, applies @var{proc} to all the packages
6069 depended on and returns the resulting package. The procedure stops recursion
6070 when @var{cut?} returns true for a given package.
6074 * package Reference:: The package data type.
6075 * origin Reference:: The origin data type.
6079 @node package Reference
6080 @subsection @code{package} Reference
6082 This section summarizes all the options available in @code{package}
6083 declarations (@pxref{Defining Packages}).
6085 @deftp {Data Type} package
6086 This is the data type representing a package recipe.
6090 The name of the package, as a string.
6092 @item @code{version}
6093 The version of the package, as a string.
6096 An object telling how the source code for the package should be
6097 acquired. Most of the time, this is an @code{origin} object, which
6098 denotes a file fetched from the Internet (@pxref{origin Reference}). It
6099 can also be any other ``file-like'' object such as a @code{local-file},
6100 which denotes a file from the local file system (@pxref{G-Expressions,
6101 @code{local-file}}).
6103 @item @code{build-system}
6104 The build system that should be used to build the package (@pxref{Build
6107 @item @code{arguments} (default: @code{'()})
6108 The arguments that should be passed to the build system. This is a
6109 list, typically containing sequential keyword-value pairs.
6111 @item @code{inputs} (default: @code{'()})
6112 @itemx @code{native-inputs} (default: @code{'()})
6113 @itemx @code{propagated-inputs} (default: @code{'()})
6114 @cindex inputs, of packages
6115 These fields list dependencies of the package. Each one is a list of
6116 tuples, where each tuple has a label for the input (a string) as its
6117 first element, a package, origin, or derivation as its second element,
6118 and optionally the name of the output thereof that should be used, which
6119 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
6120 more on package outputs). For example, the list below specifies three
6124 `(("libffi" ,libffi)
6125 ("libunistring" ,libunistring)
6126 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
6129 @cindex cross compilation, package dependencies
6130 The distinction between @code{native-inputs} and @code{inputs} is
6131 necessary when considering cross-compilation. When cross-compiling,
6132 dependencies listed in @code{inputs} are built for the @emph{target}
6133 architecture; conversely, dependencies listed in @code{native-inputs}
6134 are built for the architecture of the @emph{build} machine.
6136 @code{native-inputs} is typically used to list tools needed at
6137 build time, but not at run time, such as Autoconf, Automake, pkg-config,
6138 Gettext, or Bison. @command{guix lint} can report likely mistakes in
6139 this area (@pxref{Invoking guix lint}).
6141 @anchor{package-propagated-inputs}
6142 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
6143 specified packages will be automatically installed alongside the package
6144 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
6145 package}}, for information on how @command{guix package} deals with
6148 For example this is necessary when a C/C++ library needs headers of
6149 another library to compile, or when a pkg-config file refers to another
6150 one @i{via} its @code{Requires} field.
6152 Another example where @code{propagated-inputs} is useful is for languages
6153 that lack a facility to record the run-time search path akin to the
6154 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
6155 more. To ensure that libraries written in those languages can find
6156 library code they depend on at run time, run-time dependencies must be
6157 listed in @code{propagated-inputs} rather than @code{inputs}.
6159 @item @code{outputs} (default: @code{'("out")})
6160 The list of output names of the package. @xref{Packages with Multiple
6161 Outputs}, for typical uses of additional outputs.
6163 @item @code{native-search-paths} (default: @code{'()})
6164 @itemx @code{search-paths} (default: @code{'()})
6165 A list of @code{search-path-specification} objects describing
6166 search-path environment variables honored by the package.
6168 @item @code{replacement} (default: @code{#f})
6169 This must be either @code{#f} or a package object that will be used as a
6170 @dfn{replacement} for this package. @xref{Security Updates, grafts},
6173 @item @code{synopsis}
6174 A one-line description of the package.
6176 @item @code{description}
6177 A more elaborate description of the package.
6179 @item @code{license}
6180 @cindex license, of packages
6181 The license of the package; a value from @code{(guix licenses)},
6182 or a list of such values.
6184 @item @code{home-page}
6185 The URL to the home-page of the package, as a string.
6187 @item @code{supported-systems} (default: @code{%supported-systems})
6188 The list of systems supported by the package, as strings of the form
6189 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
6191 @item @code{location} (default: source location of the @code{package} form)
6192 The source location of the package. It is useful to override this when
6193 inheriting from another package, in which case this field is not
6194 automatically corrected.
6198 @deffn {Scheme Syntax} this-package
6199 When used in the @emph{lexical scope} of a package field definition, this
6200 identifier resolves to the package being defined.
6202 The example below shows how to add a package as a native input of itself when
6210 ;; When cross-compiled, Guile, for example, depends on
6211 ;; a native version of itself. Add it here.
6212 (native-inputs (if (%current-target-system)
6213 `(("self" ,this-package))
6217 It is an error to refer to @code{this-package} outside a package definition.
6220 @node origin Reference
6221 @subsection @code{origin} Reference
6223 This section summarizes all the options available in @code{origin}
6224 declarations (@pxref{Defining Packages}).
6226 @deftp {Data Type} origin
6227 This is the data type representing a source code origin.
6231 An object containing the URI of the source. The object type depends on
6232 the @code{method} (see below). For example, when using the
6233 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
6234 values are: a URL represented as a string, or a list thereof.
6237 A procedure that handles the URI.
6242 @item @var{url-fetch} from @code{(guix download)}
6243 download a file from the HTTP, HTTPS, or FTP URL specified in the
6247 @item @var{git-fetch} from @code{(guix git-download)}
6248 clone the Git version control repository, and check out the revision
6249 specified in the @code{uri} field as a @code{git-reference} object; a
6250 @code{git-reference} looks like this:
6254 (url "https://git.savannah.gnu.org/git/hello.git")
6260 A bytevector containing the SHA-256 hash of the source. This is
6261 equivalent to providing a @code{content-hash} SHA256 object in the
6262 @code{hash} field described below.
6265 The @code{content-hash} object of the source---see below for how to use
6266 @code{content-hash}.
6268 You can obtain this information using @code{guix download}
6269 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
6272 @item @code{file-name} (default: @code{#f})
6273 The file name under which the source code should be saved. When this is
6274 @code{#f}, a sensible default value will be used in most cases. In case
6275 the source is fetched from a URL, the file name from the URL will be
6276 used. For version control checkouts, it is recommended to provide the
6277 file name explicitly because the default is not very descriptive.
6279 @item @code{patches} (default: @code{'()})
6280 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
6281 file-like objects}) pointing to patches to be applied to the source.
6283 This list of patches must be unconditional. In particular, it cannot
6284 depend on the value of @code{%current-system} or
6285 @code{%current-target-system}.
6287 @item @code{snippet} (default: @code{#f})
6288 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
6289 in the source directory. This is a convenient way to modify the source,
6290 sometimes more convenient than a patch.
6292 @item @code{patch-flags} (default: @code{'("-p1")})
6293 A list of command-line flags that should be passed to the @code{patch}
6296 @item @code{patch-inputs} (default: @code{#f})
6297 Input packages or derivations to the patching process. When this is
6298 @code{#f}, the usual set of inputs necessary for patching are provided,
6299 such as GNU@tie{}Patch.
6301 @item @code{modules} (default: @code{'()})
6302 A list of Guile modules that should be loaded during the patching
6303 process and while running the code in the @code{snippet} field.
6305 @item @code{patch-guile} (default: @code{#f})
6306 The Guile package that should be used in the patching process. When
6307 this is @code{#f}, a sensible default is used.
6311 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
6312 Construct a content hash object for the given @var{algorithm}, and with
6313 @var{value} as its hash value. When @var{algorithm} is omitted, assume
6314 it is @code{sha256}.
6316 @var{value} can be a literal string, in which case it is base32-decoded,
6317 or it can be a bytevector.
6319 The following forms are all equivalent:
6322 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
6323 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
6325 (content-hash (base32
6326 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
6327 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
6331 Technically, @code{content-hash} is currently implemented as a macro.
6332 It performs sanity checks at macro-expansion time, when possible, such
6333 as ensuring that @var{value} has the right size for @var{algorithm}.
6337 @section Build Systems
6339 @cindex build system
6340 Each package definition specifies a @dfn{build system} and arguments for
6341 that build system (@pxref{Defining Packages}). This @code{build-system}
6342 field represents the build procedure of the package, as well as implicit
6343 dependencies of that build procedure.
6345 Build systems are @code{<build-system>} objects. The interface to
6346 create and manipulate them is provided by the @code{(guix build-system)}
6347 module, and actual build systems are exported by specific modules.
6349 @cindex bag (low-level package representation)
6350 Under the hood, build systems first compile package objects to
6351 @dfn{bags}. A @dfn{bag} is like a package, but with less
6352 ornamentation---in other words, a bag is a lower-level representation of
6353 a package, which includes all the inputs of that package, including some
6354 that were implicitly added by the build system. This intermediate
6355 representation is then compiled to a derivation (@pxref{Derivations}).
6357 Build systems accept an optional list of @dfn{arguments}. In package
6358 definitions, these are passed @i{via} the @code{arguments} field
6359 (@pxref{Defining Packages}). They are typically keyword arguments
6360 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
6361 Guile Reference Manual}). The value of these arguments is usually
6362 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
6363 by the daemon (@pxref{Derivations}).
6365 The main build system is @code{gnu-build-system}, which implements the
6366 standard build procedure for GNU and many other packages. It
6367 is provided by the @code{(guix build-system gnu)} module.
6369 @defvr {Scheme Variable} gnu-build-system
6370 @code{gnu-build-system} represents the GNU Build System, and variants
6371 thereof (@pxref{Configuration, configuration and makefile conventions,,
6372 standards, GNU Coding Standards}).
6374 @cindex build phases
6375 In a nutshell, packages using it are configured, built, and installed with
6376 the usual @code{./configure && make && make check && make install}
6377 command sequence. In practice, a few additional steps are often needed.
6378 All these steps are split up in separate @dfn{phases},
6379 notably@footnote{Please see the @code{(guix build gnu-build-system)}
6380 modules for more details about the build phases.}:
6384 Unpack the source tarball, and change the current directory to the
6385 extracted source tree. If the source is actually a directory, copy it
6386 to the build tree, and enter that directory.
6388 @item patch-source-shebangs
6389 Patch shebangs encountered in source files so they refer to the right
6390 store file names. For instance, this changes @code{#!/bin/sh} to
6391 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
6394 Run the @file{configure} script with a number of default options, such
6395 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
6396 by the @code{#:configure-flags} argument.
6399 Run @code{make} with the list of flags specified with
6400 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
6401 (the default), build with @code{make -j}.
6404 Run @code{make check}, or some other target specified with
6405 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
6406 @code{#:parallel-tests?} argument is true (the default), run @code{make
6410 Run @code{make install} with the flags listed in @code{#:make-flags}.
6412 @item patch-shebangs
6413 Patch shebangs on the installed executable files.
6416 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
6417 is false), copying them to the @code{debug} output when available
6418 (@pxref{Installing Debugging Files}).
6421 @vindex %standard-phases
6422 The build-side module @code{(guix build gnu-build-system)} defines
6423 @code{%standard-phases} as the default list of build phases.
6424 @code{%standard-phases} is a list of symbol/procedure pairs, where the
6425 procedure implements the actual phase.
6427 The list of phases used for a particular package can be changed with the
6428 @code{#:phases} parameter. For instance, passing:
6431 #:phases (modify-phases %standard-phases (delete 'configure))
6434 means that all the phases described above will be used, except the
6435 @code{configure} phase.
6437 In addition, this build system ensures that the ``standard'' environment
6438 for GNU packages is available. This includes tools such as GCC, libc,
6439 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
6440 build-system gnu)} module for a complete list). We call these the
6441 @dfn{implicit inputs} of a package, because package definitions do not
6442 have to mention them.
6445 Other @code{<build-system>} objects are defined to support other
6446 conventions and tools used by free software packages. They inherit most
6447 of @code{gnu-build-system}, and differ mainly in the set of inputs
6448 implicitly added to the build process, and in the list of phases
6449 executed. Some of these build systems are listed below.
6451 @defvr {Scheme Variable} ant-build-system
6452 This variable is exported by @code{(guix build-system ant)}. It
6453 implements the build procedure for Java packages that can be built with
6454 @url{https://ant.apache.org/, Ant build tool}.
6456 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
6457 provided by the @code{icedtea} package to the set of inputs. Different
6458 packages can be specified with the @code{#:ant} and @code{#:jdk}
6459 parameters, respectively.
6461 When the original package does not provide a suitable Ant build file,
6462 the parameter @code{#:jar-name} can be used to generate a minimal Ant
6463 build file @file{build.xml} with tasks to build the specified jar
6464 archive. In this case the parameter @code{#:source-dir} can be used to
6465 specify the source sub-directory, defaulting to ``src''.
6467 The @code{#:main-class} parameter can be used with the minimal ant
6468 buildfile to specify the main class of the resulting jar. This makes the
6469 jar file executable. The @code{#:test-include} parameter can be used to
6470 specify the list of junit tests to run. It defaults to
6471 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
6472 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
6473 because abstract classes cannot be run as tests.
6475 The parameter @code{#:build-target} can be used to specify the Ant task
6476 that should be run during the @code{build} phase. By default the
6477 ``jar'' task will be run.
6481 @defvr {Scheme Variable} android-ndk-build-system
6482 @cindex Android distribution
6483 @cindex Android NDK build system
6484 This variable is exported by @code{(guix build-system android-ndk)}. It
6485 implements a build procedure for Android NDK (native development kit)
6486 packages using a Guix-specific build process.
6488 The build system assumes that packages install their public interface
6489 (header) files to the subdirectory @file{include} of the @code{out} output and
6490 their libraries to the subdirectory @file{lib} the @code{out} output.
6492 It's also assumed that the union of all the dependencies of a package
6493 has no conflicting files.
6495 For the time being, cross-compilation is not supported - so right now
6496 the libraries and header files are assumed to be host tools.
6500 @defvr {Scheme Variable} asdf-build-system/source
6501 @defvrx {Scheme Variable} asdf-build-system/sbcl
6502 @defvrx {Scheme Variable} asdf-build-system/ecl
6504 These variables, exported by @code{(guix build-system asdf)}, implement
6505 build procedures for Common Lisp packages using
6506 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
6507 definition facility for Common Lisp programs and libraries.
6509 The @code{asdf-build-system/source} system installs the packages in
6510 source form, and can be loaded using any common lisp implementation, via
6511 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
6512 systems in the format which a particular implementation understands.
6513 These build systems can also be used to produce executable programs, or
6514 lisp images which contain a set of packages pre-loaded.
6516 The build system uses naming conventions. For binary packages, the
6517 package name should be prefixed with the lisp implementation, such as
6518 @code{sbcl-} for @code{asdf-build-system/sbcl}.
6520 Additionally, the corresponding source package should be labeled using
6521 the same convention as python packages (see @ref{Python Modules}), using
6522 the @code{cl-} prefix.
6524 For binary packages, each system should be defined as a Guix package.
6525 If one package @code{origin} contains several systems, package variants
6526 can be created in order to build all the systems. Source packages,
6527 which use @code{asdf-build-system/source}, may contain several systems.
6529 In order to create executable programs and images, the build-side
6530 procedures @code{build-program} and @code{build-image} can be used.
6531 They should be called in a build phase after the @code{create-symlinks}
6532 phase, so that the system which was just built can be used within the
6533 resulting image. @code{build-program} requires a list of Common Lisp
6534 expressions to be passed as the @code{#:entry-program} argument.
6536 If the system is not defined within its own @file{.asd} file of the same
6537 name, then the @code{#:asd-file} parameter should be used to specify
6538 which file the system is defined in. Furthermore, if the package
6539 defines a system for its tests in a separate file, it will be loaded
6540 before the tests are run if it is specified by the
6541 @code{#:test-asd-file} parameter. If it is not set, the files
6542 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
6543 and @code{test.asd} will be tried if they exist.
6545 If for some reason the package must be named in a different way than the
6546 naming conventions suggest, the @code{#:asd-system-name} parameter can
6547 be used to specify the name of the system.
6551 @defvr {Scheme Variable} cargo-build-system
6552 @cindex Rust programming language
6553 @cindex Cargo (Rust build system)
6554 This variable is exported by @code{(guix build-system cargo)}. It
6555 supports builds of packages using Cargo, the build tool of the
6556 @uref{https://www.rust-lang.org, Rust programming language}.
6558 It adds @code{rustc} and @code{cargo} to the set of inputs.
6559 A different Rust package can be specified with the @code{#:rust} parameter.
6561 Regular cargo dependencies should be added to the package definition via the
6562 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
6563 spec can be a package or a source definition. Note that the spec must
6564 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
6565 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
6566 should be added to the package definition via the
6567 @code{#:cargo-development-inputs} parameter.
6569 In its @code{configure} phase, this build system will make any source inputs
6570 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
6571 parameters available to cargo. It will also remove an included
6572 @code{Cargo.lock} file to be recreated by @code{cargo} during the
6573 @code{build} phase. The @code{install} phase installs any crate the binaries
6574 if they are defined by the crate.
6578 @defvr {Scheme Variable} copy-build-system
6579 This variable is exported by @code{(guix build-system copy)}. It
6580 supports builds of simple packages that don't require much compiling,
6581 mostly just moving files around.
6583 It adds much of the @code{gnu-build-system} packages to the set of
6584 inputs. Because of this, the @code{copy-build-system} does not require
6585 all the boilerplate code often needed for the
6586 @code{trivial-build-system}.
6588 To further simplify the file installation process, an
6589 @code{#:install-plan} argument is exposed to let the packager specify
6590 which files go where. The install plan is a list of @code{(@var{source}
6591 @var{target} [@var{filters}])}. @var{filters} are optional.
6594 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
6596 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
6597 @item Otherwise install @var{source} as @var{target}.
6600 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
6601 the trailing slash of @var{target} is implied with the same meaning
6604 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
6605 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
6606 @code{#:exclude-regexp}, only select files are installed depending on
6607 the filters. Each filters is specified by a list of strings.
6609 @item With @code{#:include}, install all the files which the path suffix matches
6610 at least one of the elements in the given list.
6611 @item With @code{#:include-regexp}, install all the files which the
6612 subpaths match at least one of the regular expressions in the given
6614 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
6615 are the complement of their inclusion counterpart. Without @code{#:include} flags,
6616 install all files but those matching the exclusion filters.
6617 If both inclusions and exclusions are specified, the exclusions are done
6618 on top of the inclusions.
6621 In all cases, the paths relative to @var{source} are preserved within
6628 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
6629 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
6630 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
6631 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
6632 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
6633 @file{share/my-app/sub/file}.
6634 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
6635 @file{share/my-app/file}.
6640 @cindex Clojure (programming language)
6641 @cindex simple Clojure build system
6642 @defvr {Scheme Variable} clojure-build-system
6643 This variable is exported by @code{(guix build-system clojure)}. It implements
6644 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
6645 using plain old @code{compile} in Clojure. Cross-compilation is not supported
6648 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
6649 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
6650 @code{#:zip} parameters, respectively.
6652 A list of source directories, test directories and jar names can be specified
6653 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
6654 parameters, respectively. Compile directory and main class can be specified
6655 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
6656 Other parameters are documented below.
6658 This build system is an extension of @code{ant-build-system}, but with the
6659 following phases changed:
6664 This phase calls @code{compile} in Clojure to compile source files and runs
6665 @command{jar} to create jars from both source files and compiled files
6666 according to the include list and exclude list specified in
6667 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
6668 has priority over the include list. These lists consist of symbols
6669 representing Clojure libraries or the special keyword @code{#:all} representing
6670 all Clojure libraries found under the source directories. The parameter
6671 @code{#:omit-source?} decides if source should be included into the jars.
6674 This phase runs tests according to the include list and exclude list specified
6675 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
6676 meanings are analogous to that of @code{#:aot-include} and
6677 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
6678 stands for all Clojure libraries found under the test directories. The
6679 parameter @code{#:tests?} decides if tests should be run.
6682 This phase installs all jars built previously.
6685 Apart from the above, this build system also contains an additional phase:
6690 This phase installs all top-level files with base name matching
6691 @code{%doc-regex}. A different regex can be specified with the
6692 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
6693 directories specified in @code{#:doc-dirs} are installed as well.
6697 @defvr {Scheme Variable} cmake-build-system
6698 This variable is exported by @code{(guix build-system cmake)}. It
6699 implements the build procedure for packages using the
6700 @url{https://www.cmake.org, CMake build tool}.
6702 It automatically adds the @code{cmake} package to the set of inputs.
6703 Which package is used can be specified with the @code{#:cmake}
6706 The @code{#:configure-flags} parameter is taken as a list of flags
6707 passed to the @command{cmake} command. The @code{#:build-type}
6708 parameter specifies in abstract terms the flags passed to the compiler;
6709 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
6710 debugging information''), which roughly means that code is compiled with
6711 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
6714 @defvr {Scheme Variable} dune-build-system
6715 This variable is exported by @code{(guix build-system dune)}. It
6716 supports builds of packages using @uref{https://dune.build/, Dune}, a build
6717 tool for the OCaml programming language. It is implemented as an extension
6718 of the @code{ocaml-build-system} which is described below. As such, the
6719 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
6722 It automatically adds the @code{dune} package to the set of inputs.
6723 Which package is used can be specified with the @code{#:dune}
6726 There is no @code{configure} phase because dune packages typically don't
6727 need to be configured. The @code{#:build-flags} parameter is taken as a
6728 list of flags passed to the @code{dune} command during the build.
6730 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
6731 command instead of the more recent @code{dune} command while building
6732 a package. Its default value is @code{#f}.
6734 The @code{#:package} parameter can be passed to specify a package name, which
6735 is useful when a package contains multiple packages and you want to build
6736 only one of them. This is equivalent to passing the @code{-p} argument to
6740 @defvr {Scheme Variable} go-build-system
6741 This variable is exported by @code{(guix build-system go)}. It
6742 implements a build procedure for Go packages using the standard
6743 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
6744 Go build mechanisms}.
6746 The user is expected to provide a value for the key @code{#:import-path}
6747 and, in some cases, @code{#:unpack-path}. The
6748 @url{https://golang.org/doc/code.html#ImportPaths, import path}
6749 corresponds to the file system path expected by the package's build
6750 scripts and any referring packages, and provides a unique way to
6751 refer to a Go package. It is typically based on a combination of the
6752 package source code's remote URI and file system hierarchy structure. In
6753 some cases, you will need to unpack the package's source code to a
6754 different directory structure than the one indicated by the import path,
6755 and @code{#:unpack-path} should be used in such cases.
6757 Packages that provide Go libraries should install their source code into
6758 the built output. The key @code{#:install-source?}, which defaults to
6759 @code{#t}, controls whether or not the source code is installed. It can
6760 be set to @code{#f} for packages that only provide executable files.
6763 @defvr {Scheme Variable} glib-or-gtk-build-system
6764 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
6765 is intended for use with packages making use of GLib or GTK+.
6767 This build system adds the following two phases to the ones defined by
6768 @code{gnu-build-system}:
6771 @item glib-or-gtk-wrap
6772 The phase @code{glib-or-gtk-wrap} ensures that programs in
6773 @file{bin/} are able to find GLib ``schemas'' and
6774 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
6775 modules}. This is achieved by wrapping the programs in launch scripts
6776 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
6777 environment variables.
6779 It is possible to exclude specific package outputs from that wrapping
6780 process by listing their names in the
6781 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
6782 when an output is known not to contain any GLib or GTK+ binaries, and
6783 where wrapping would gratuitously add a dependency of that output on
6786 @item glib-or-gtk-compile-schemas
6787 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
6788 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
6789 GSettings schemas} of GLib are compiled. Compilation is performed by the
6790 @command{glib-compile-schemas} program. It is provided by the package
6791 @code{glib:bin} which is automatically imported by the build system.
6792 The @code{glib} package providing @command{glib-compile-schemas} can be
6793 specified with the @code{#:glib} parameter.
6796 Both phases are executed after the @code{install} phase.
6799 @defvr {Scheme Variable} guile-build-system
6800 This build system is for Guile packages that consist exclusively of Scheme
6801 code and that are so lean that they don't even have a makefile, let alone a
6802 @file{configure} script. It compiles Scheme code using @command{guild
6803 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6804 installs the @file{.scm} and @file{.go} files in the right place. It also
6805 installs documentation.
6807 This build system supports cross-compilation by using the
6808 @option{--target} option of @samp{guild compile}.
6810 Packages built with @code{guile-build-system} must provide a Guile package in
6811 their @code{native-inputs} field.
6814 @defvr {Scheme Variable} julia-build-system
6815 This variable is exported by @code{(guix build-system julia)}. It
6816 implements the build procedure used by @uref{https://julialang.org/,
6817 julia} packages, which essentially is similar to running @samp{julia -e
6818 'using Pkg; Pkg.add(package)'} in an environment where
6819 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
6820 Tests are run not run.
6822 Julia packages require the source @code{file-name} to be the real name of the
6823 package, correctly capitalized.
6825 For packages requiring shared library dependencies, you may need to write the
6826 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
6827 variable = /gnu/store/library.so} for each dependency, plus a void function
6828 @code{check_deps() = nothing}.
6830 Some older packages that aren't using @file{Package.toml} yet, will require
6831 this file to be created, too. The function @code{julia-create-package-toml}
6832 helps creating the file. You need to pass the outputs and the source of the
6833 package, it's name (the same as the @code{file-name} parameter), the package
6834 uuid, the package version, and a list of dependencies specified by their name
6838 @defvr {Scheme Variable} maven-build-system
6839 This variable is exported by @code{(guix build-system maven)}. It implements
6840 a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
6841 is a dependency and lifecycle management tool for Java. A user of Maven
6842 specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
6843 When Maven does not have one of the dependencies or plugins in its repository,
6844 it will download them and use them to build the package.
6846 The maven build system ensures that maven will not try to download any
6847 dependency by running in offline mode. Maven will fail if a dependency is
6848 missing. Before running Maven, the @file{pom.xml} (and subprojects) are
6849 modified to specify the version of dependencies and plugins that match the
6850 versions available in the guix build environment. Dependencies and plugins
6851 must be installed in the fake maven repository at @file{lib/m2}, and are
6852 symlinked into a proper repository before maven is run. Maven is instructed
6853 to use that repository for the build and installs built artifacts there.
6854 Changed files are copied to the @file{lib/m2} directory of the package output.
6856 You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
6857 or let the build system use the default @file{pom.xml} file in the sources.
6859 In case you need to specify a dependency's version manually, you can use the
6860 @code{#:local-packages} argument. It takes an association list where the key
6861 is the groupId of the package and its value is an association list where the
6862 key is the artifactId of the package and its value is the version you want to
6863 override in the @file{pom.xml}.
6865 Some packages use dependencies or plugins that are not useful at runtime nor
6866 at build time in Guix. You can alter the @file{pom.xml} file to remove them
6867 using the @code{#:exclude} argument. Its value is an association list where
6868 the key is the groupId of the plugin or dependency you want to remove, and
6869 the value is a list of artifactId you want to remove.
6871 You can override the default @code{jdk} and @code{maven} packages with the
6872 corresponding argument, @code{#:jdk} and @code{#:maven}.
6874 The @code{#:maven-plugins} argument is a list of maven plugins used during
6875 the build, with the same format as the @code{inputs} fields of the package
6876 declaration. Its default value is @code{(default-maven-plugins)} which is
6880 @defvr {Scheme Variable} minify-build-system
6881 This variable is exported by @code{(guix build-system minify)}. It
6882 implements a minification procedure for simple JavaScript packages.
6884 It adds @code{uglify-js} to the set of inputs and uses it to compress
6885 all JavaScript files in the @file{src} directory. A different minifier
6886 package can be specified with the @code{#:uglify-js} parameter, but it
6887 is expected that the package writes the minified code to the standard
6890 When the input JavaScript files are not all located in the @file{src}
6891 directory, the parameter @code{#:javascript-files} can be used to
6892 specify a list of file names to feed to the minifier.
6895 @defvr {Scheme Variable} ocaml-build-system
6896 This variable is exported by @code{(guix build-system ocaml)}. It implements
6897 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6898 of choosing the correct set of commands to run for each package. OCaml
6899 packages can expect many different commands to be run. This build system will
6902 When the package has a @file{setup.ml} file present at the top-level, it will
6903 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6904 @code{ocaml setup.ml -install}. The build system will assume that this file
6905 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6906 care of setting the prefix and enabling tests if they are not disabled. You
6907 can pass configure and build flags with the @code{#:configure-flags} and
6908 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6909 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6910 bypass this system in the build and install phases.
6912 When the package has a @file{configure} file, it is assumed that it is a
6913 hand-made configure script that requires a different argument format than
6914 in the @code{gnu-build-system}. You can add more flags with the
6915 @code{#:configure-flags} key.
6917 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6918 @code{#t}), it will be used and more flags can be passed to the build and
6919 install phases with the @code{#:make-flags} key.
6921 Finally, some packages do not have these files and use a somewhat standard
6922 location for its build system. In that case, the build system will run
6923 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6924 providing the path to the required findlib module. Additional flags can
6925 be passed via the @code{#:build-flags} key. Install is taken care of by
6926 @command{opam-installer}. In this case, the @code{opam} package must
6927 be added to the @code{native-inputs} field of the package definition.
6929 Note that most OCaml packages assume they will be installed in the same
6930 directory as OCaml, which is not what we want in guix. In particular, they
6931 will install @file{.so} files in their module's directory, which is usually
6932 fine because it is in the OCaml compiler directory. In guix though, these
6933 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
6934 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6935 @file{.so} libraries should be installed.
6938 @defvr {Scheme Variable} python-build-system
6939 This variable is exported by @code{(guix build-system python)}. It
6940 implements the more or less standard build procedure used by Python
6941 packages, which consists in running @code{python setup.py build} and
6942 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6944 For packages that install stand-alone Python programs under @code{bin/},
6945 it takes care of wrapping these programs so that their @env{PYTHONPATH}
6946 environment variable points to all the Python libraries they depend on.
6948 Which Python package is used to perform the build can be specified with
6949 the @code{#:python} parameter. This is a useful way to force a package
6950 to be built for a specific version of the Python interpreter, which
6951 might be necessary if the package is only compatible with a single
6952 interpreter version.
6954 By default guix calls @code{setup.py} under control of
6955 @code{setuptools}, much like @command{pip} does. Some packages are not
6956 compatible with setuptools (and pip), thus you can disable this by
6957 setting the @code{#:use-setuptools?} parameter to @code{#f}.
6960 @defvr {Scheme Variable} perl-build-system
6961 This variable is exported by @code{(guix build-system perl)}. It
6962 implements the standard build procedure for Perl packages, which either
6963 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6964 followed by @code{Build} and @code{Build install}; or in running
6965 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6966 @code{make} and @code{make install}, depending on which of
6967 @code{Build.PL} or @code{Makefile.PL} is present in the package
6968 distribution. Preference is given to the former if both @code{Build.PL}
6969 and @code{Makefile.PL} exist in the package distribution. This
6970 preference can be reversed by specifying @code{#t} for the
6971 @code{#:make-maker?} parameter.
6973 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6974 passes flags specified by the @code{#:make-maker-flags} or
6975 @code{#:module-build-flags} parameter, respectively.
6977 Which Perl package is used can be specified with @code{#:perl}.
6980 @defvr {Scheme Variable} qt-build-system
6981 This variable is exported by @code{(guix build-system qt)}. It
6982 is intended for use with applications using Qt or KDE.
6984 This build system adds the following two phases to the ones defined by
6985 @code{cmake-build-system}:
6989 The phase @code{check-setup} prepares the environment for running
6990 the checks as commonly used by Qt test programs.
6991 For now this only sets some environment variables:
6992 @code{QT_QPA_PLATFORM=offscreen},
6993 @code{DBUS_FATAL_WARNINGS=0} and
6994 @code{CTEST_OUTPUT_ON_FAILURE=1}.
6996 This phase is added before the @code{check} phase.
6997 It's a separate phase to ease adjusting if necessary.
7000 The phase @code{qt-wrap}
7001 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
7002 and output. In case some path is found, all programs in the output's
7003 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
7004 are wrapped in scripts defining the necessary environment variables.
7006 It is possible to exclude specific package outputs from that wrapping process
7007 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
7008 This is useful when an output is known not to contain any Qt binaries, and
7009 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
7012 This phase is added after the @code{install} phase.
7016 @defvr {Scheme Variable} r-build-system
7017 This variable is exported by @code{(guix build-system r)}. It
7018 implements the build procedure used by @uref{https://r-project.org, R}
7019 packages, which essentially is little more than running @samp{R CMD
7020 INSTALL --library=/gnu/store/@dots{}} in an environment where
7021 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
7022 run after installation using the R function
7023 @code{tools::testInstalledPackage}.
7026 @defvr {Scheme Variable} rakudo-build-system
7027 This variable is exported by @code{(guix build-system rakudo)}. It
7028 implements the build procedure used by @uref{https://rakudo.org/,
7029 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
7030 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
7031 installs the binaries, library files and the resources, as well as wrap
7032 the files under the @code{bin/} directory. Tests can be skipped by
7033 passing @code{#f} to the @code{tests?} parameter.
7035 Which rakudo package is used can be specified with @code{rakudo}.
7036 Which perl6-tap-harness package used for the tests can be specified with
7037 @code{#:prove6} or removed by passing @code{#f} to the
7038 @code{with-prove6?} parameter.
7039 Which perl6-zef package used for tests and installing can be specified
7040 with @code{#:zef} or removed by passing @code{#f} to the
7041 @code{with-zef?} parameter.
7044 @defvr {Scheme Variable} texlive-build-system
7045 This variable is exported by @code{(guix build-system texlive)}. It is
7046 used to build TeX packages in batch mode with a specified engine. The
7047 build system sets the @env{TEXINPUTS} variable to find all TeX source
7048 files in the inputs.
7050 By default it runs @code{luatex} on all files ending on @code{ins}. A
7051 different engine and format can be specified with the
7052 @code{#:tex-format} argument. Different build targets can be specified
7053 with the @code{#:build-targets} argument, which expects a list of file
7054 names. The build system adds only @code{texlive-bin} and
7055 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
7056 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
7057 and @code{#:texlive-latex-base}, respectively.
7059 The @code{#:tex-directory} parameter tells the build system where to
7060 install the built files under the texmf tree.
7063 @defvr {Scheme Variable} ruby-build-system
7064 This variable is exported by @code{(guix build-system ruby)}. It
7065 implements the RubyGems build procedure used by Ruby packages, which
7066 involves running @code{gem build} followed by @code{gem install}.
7068 The @code{source} field of a package that uses this build system
7069 typically references a gem archive, since this is the format that Ruby
7070 developers use when releasing their software. The build system unpacks
7071 the gem archive, potentially patches the source, runs the test suite,
7072 repackages the gem, and installs it. Additionally, directories and
7073 tarballs may be referenced to allow building unreleased gems from Git or
7074 a traditional source release tarball.
7076 Which Ruby package is used can be specified with the @code{#:ruby}
7077 parameter. A list of additional flags to be passed to the @command{gem}
7078 command can be specified with the @code{#:gem-flags} parameter.
7081 @defvr {Scheme Variable} waf-build-system
7082 This variable is exported by @code{(guix build-system waf)}. It
7083 implements a build procedure around the @code{waf} script. The common
7084 phases---@code{configure}, @code{build}, and @code{install}---are
7085 implemented by passing their names as arguments to the @code{waf}
7088 The @code{waf} script is executed by the Python interpreter. Which
7089 Python package is used to run the script can be specified with the
7090 @code{#:python} parameter.
7093 @defvr {Scheme Variable} scons-build-system
7094 This variable is exported by @code{(guix build-system scons)}. It
7095 implements the build procedure used by the SCons software construction
7096 tool. This build system runs @code{scons} to build the package,
7097 @code{scons test} to run tests, and then @code{scons install} to install
7100 Additional flags to be passed to @code{scons} can be specified with the
7101 @code{#:scons-flags} parameter. The default build and install targets
7102 can be overridden with @code{#:build-targets} and
7103 @code{#:install-targets} respectively. The version of Python used to
7104 run SCons can be specified by selecting the appropriate SCons package
7105 with the @code{#:scons} parameter.
7108 @defvr {Scheme Variable} haskell-build-system
7109 This variable is exported by @code{(guix build-system haskell)}. It
7110 implements the Cabal build procedure used by Haskell packages, which
7111 involves running @code{runhaskell Setup.hs configure
7112 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
7113 Instead of installing the package by running @code{runhaskell Setup.hs
7114 install}, to avoid trying to register libraries in the read-only
7115 compiler store directory, the build system uses @code{runhaskell
7116 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
7117 addition, the build system generates the package documentation by
7118 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
7119 is passed. Optional Haddock parameters can be passed with the help of
7120 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
7121 not found, the build system looks for @code{Setup.lhs} instead.
7123 Which Haskell compiler is used can be specified with the @code{#:haskell}
7124 parameter which defaults to @code{ghc}.
7127 @defvr {Scheme Variable} dub-build-system
7128 This variable is exported by @code{(guix build-system dub)}. It
7129 implements the Dub build procedure used by D packages, which
7130 involves running @code{dub build} and @code{dub run}.
7131 Installation is done by copying the files manually.
7133 Which D compiler is used can be specified with the @code{#:ldc}
7134 parameter which defaults to @code{ldc}.
7137 @defvr {Scheme Variable} emacs-build-system
7138 This variable is exported by @code{(guix build-system emacs)}. It
7139 implements an installation procedure similar to the packaging system
7140 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
7142 It first creates the @code{@code{package}-autoloads.el} file, then it
7143 byte compiles all Emacs Lisp files. Differently from the Emacs
7144 packaging system, the Info documentation files are moved to the standard
7145 documentation directory and the @file{dir} file is deleted. The Elisp
7146 package files are installed directly under @file{share/emacs/site-lisp}.
7149 @defvr {Scheme Variable} font-build-system
7150 This variable is exported by @code{(guix build-system font)}. It
7151 implements an installation procedure for font packages where upstream
7152 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
7153 need to be copied into place. It copies font files to standard
7154 locations in the output directory.
7157 @defvr {Scheme Variable} meson-build-system
7158 This variable is exported by @code{(guix build-system meson)}. It
7159 implements the build procedure for packages that use
7160 @url{https://mesonbuild.com, Meson} as their build system.
7162 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
7163 of inputs, and they can be changed with the parameters @code{#:meson}
7164 and @code{#:ninja} if needed. The default Meson is
7165 @code{meson-for-build}, which is special because it doesn't clear the
7166 @code{RUNPATH} of binaries and libraries when they are installed.
7168 This build system is an extension of @code{gnu-build-system}, but with the
7169 following phases changed to some specific for Meson:
7174 The phase runs @code{meson} with the flags specified in
7175 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
7176 @code{debugoptimized} unless something else is specified in
7177 @code{#:build-type}.
7180 The phase runs @code{ninja} to build the package in parallel by default, but
7181 this can be changed with @code{#:parallel-build?}.
7184 The phase runs @code{ninja} with the target specified in @code{#:test-target},
7185 which is @code{"test"} by default.
7188 The phase runs @code{ninja install} and can not be changed.
7191 Apart from that, the build system also adds the following phases:
7196 This phase ensures that all binaries can find the libraries they need.
7197 It searches for required libraries in subdirectories of the package being
7198 built, and adds those to @code{RUNPATH} where needed. It also removes
7199 references to libraries left over from the build phase by
7200 @code{meson-for-build}, such as test dependencies, that aren't actually
7201 required for the program to run.
7203 @item glib-or-gtk-wrap
7204 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
7205 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
7207 @item glib-or-gtk-compile-schemas
7208 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
7209 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
7213 @defvr {Scheme Variable} linux-module-build-system
7214 @code{linux-module-build-system} allows building Linux kernel modules.
7216 @cindex build phases
7217 This build system is an extension of @code{gnu-build-system}, but with the
7218 following phases changed:
7223 This phase configures the environment so that the Linux kernel's Makefile
7224 can be used to build the external kernel module.
7227 This phase uses the Linux kernel's Makefile in order to build the external
7231 This phase uses the Linux kernel's Makefile in order to install the external
7235 It is possible and useful to specify the Linux kernel to use for building
7236 the module (in the @code{arguments} form of a package using the
7237 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
7240 @defvr {Scheme Variable} node-build-system
7241 This variable is exported by @code{(guix build-system node)}. It
7242 implements the build procedure used by @uref{https://nodejs.org,
7243 Node.js}, which implements an approximation of the @code{npm install}
7244 command, followed by an @code{npm test} command.
7246 Which Node.js package is used to interpret the @code{npm} commands can
7247 be specified with the @code{#:node} parameter which defaults to
7251 Lastly, for packages that do not need anything as sophisticated, a
7252 ``trivial'' build system is provided. It is trivial in the sense that
7253 it provides basically no support: it does not pull any implicit inputs,
7254 and does not have a notion of build phases.
7256 @defvr {Scheme Variable} trivial-build-system
7257 This variable is exported by @code{(guix build-system trivial)}.
7259 This build system requires a @code{#:builder} argument. This argument
7260 must be a Scheme expression that builds the package output(s)---as
7261 with @code{build-expression->derivation} (@pxref{Derivations,
7262 @code{build-expression->derivation}}).
7272 Conceptually, the @dfn{store} is the place where derivations that have
7273 been built successfully are stored---by default, @file{/gnu/store}.
7274 Sub-directories in the store are referred to as @dfn{store items} or
7275 sometimes @dfn{store paths}. The store has an associated database that
7276 contains information such as the store paths referred to by each store
7277 path, and the list of @emph{valid} store items---results of successful
7278 builds. This database resides in @file{@var{localstatedir}/guix/db},
7279 where @var{localstatedir} is the state directory specified @i{via}
7280 @option{--localstatedir} at configure time, usually @file{/var}.
7282 The store is @emph{always} accessed by the daemon on behalf of its clients
7283 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
7284 connect to the daemon over a Unix-domain socket, send requests to it,
7285 and read the result---these are remote procedure calls, or RPCs.
7288 Users must @emph{never} modify files under @file{/gnu/store} directly.
7289 This would lead to inconsistencies and break the immutability
7290 assumptions of Guix's functional model (@pxref{Introduction}).
7292 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
7293 how to check the integrity of the store and attempt recovery from
7294 accidental modifications.
7297 The @code{(guix store)} module provides procedures to connect to the
7298 daemon, and to perform RPCs. These are described below. By default,
7299 @code{open-connection}, and thus all the @command{guix} commands,
7300 connect to the local daemon or to the URI specified by the
7301 @env{GUIX_DAEMON_SOCKET} environment variable.
7303 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
7304 When set, the value of this variable should be a file name or a URI
7305 designating the daemon endpoint. When it is a file name, it denotes a
7306 Unix-domain socket to connect to. In addition to file names, the
7307 supported URI schemes are:
7312 These are for Unix-domain sockets.
7313 @code{file:///var/guix/daemon-socket/socket} is equivalent to
7314 @file{/var/guix/daemon-socket/socket}.
7317 @cindex daemon, remote access
7318 @cindex remote access to the daemon
7319 @cindex daemon, cluster setup
7320 @cindex clusters, daemon setup
7321 These URIs denote connections over TCP/IP, without encryption nor
7322 authentication of the remote host. The URI must specify the host name
7323 and optionally a port number (by default port 44146 is used):
7326 guix://master.guix.example.org:1234
7329 This setup is suitable on local networks, such as clusters, where only
7330 trusted nodes may connect to the build daemon at
7331 @code{master.guix.example.org}.
7333 The @option{--listen} option of @command{guix-daemon} can be used to
7334 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
7335 @option{--listen}}).
7338 @cindex SSH access to build daemons
7339 These URIs allow you to connect to a remote daemon over SSH. This
7340 feature requires Guile-SSH (@pxref{Requirements}) and a working
7341 @command{guile} binary in @env{PATH} on the destination machine. It
7342 supports public key and GSSAPI authentication. A typical URL might look
7346 ssh://charlie@@guix.example.org:22
7349 As for @command{guix copy}, the usual OpenSSH client configuration files
7350 are honored (@pxref{Invoking guix copy}).
7353 Additional URI schemes may be supported in the future.
7355 @c XXX: Remove this note when the protocol incurs fewer round trips
7356 @c and when (guix derivations) no longer relies on file system access.
7358 The ability to connect to remote build daemons is considered
7359 experimental as of @value{VERSION}. Please get in touch with us to
7360 share any problems or suggestions you may have (@pxref{Contributing}).
7364 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
7365 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
7366 @var{reserve-space?} is true, instruct it to reserve a little bit of
7367 extra space on the file system so that the garbage collector can still
7368 operate should the disk become full. Return a server object.
7370 @var{file} defaults to @code{%default-socket-path}, which is the normal
7371 location given the options that were passed to @command{configure}.
7374 @deffn {Scheme Procedure} close-connection @var{server}
7375 Close the connection to @var{server}.
7378 @defvr {Scheme Variable} current-build-output-port
7379 This variable is bound to a SRFI-39 parameter, which refers to the port
7380 where build and error logs sent by the daemon should be written.
7383 Procedures that make RPCs all take a server object as their first
7386 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
7387 @cindex invalid store items
7388 Return @code{#t} when @var{path} designates a valid store item and
7389 @code{#f} otherwise (an invalid item may exist on disk but still be
7390 invalid, for instance because it is the result of an aborted or failed
7393 A @code{&store-protocol-error} condition is raised if @var{path} is not
7394 prefixed by the store directory (@file{/gnu/store}).
7397 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
7398 Add @var{text} under file @var{name} in the store, and return its store
7399 path. @var{references} is the list of store paths referred to by the
7400 resulting store path.
7403 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
7405 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
7406 file names, or derivation/output pairs, using the specified
7407 @var{mode}---@code{(build-mode normal)} by default.
7410 Note that the @code{(guix monads)} module provides a monad as well as
7411 monadic versions of the above procedures, with the goal of making it
7412 more convenient to work with code that accesses the store (@pxref{The
7416 @i{This section is currently incomplete.}
7419 @section Derivations
7422 Low-level build actions and the environment in which they are performed
7423 are represented by @dfn{derivations}. A derivation contains the
7424 following pieces of information:
7428 The outputs of the derivation---derivations produce at least one file or
7429 directory in the store, but may produce more.
7432 @cindex build-time dependencies
7433 @cindex dependencies, build-time
7434 The inputs of the derivations---i.e., its build-time dependencies---which may
7435 be other derivations or plain files in the store (patches, build scripts,
7439 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
7442 The file name of a build script in the store, along with the arguments
7446 A list of environment variables to be defined.
7450 @cindex derivation path
7451 Derivations allow clients of the daemon to communicate build actions to
7452 the store. They exist in two forms: as an in-memory representation,
7453 both on the client- and daemon-side, and as files in the store whose
7454 name end in @file{.drv}---these files are referred to as @dfn{derivation
7455 paths}. Derivations paths can be passed to the @code{build-derivations}
7456 procedure to perform the build actions they prescribe (@pxref{The
7459 @cindex fixed-output derivations
7460 Operations such as file downloads and version-control checkouts for
7461 which the expected content hash is known in advance are modeled as
7462 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
7463 of a fixed-output derivation are independent of its inputs---e.g., a
7464 source code download produces the same result regardless of the download
7465 method and tools being used.
7468 @cindex run-time dependencies
7469 @cindex dependencies, run-time
7470 The outputs of derivations---i.e., the build results---have a set of
7471 @dfn{references}, as reported by the @code{references} RPC or the
7472 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
7473 are the set of run-time dependencies of the build results. References are a
7474 subset of the inputs of the derivation; this subset is automatically computed
7475 by the build daemon by scanning all the files in the outputs.
7477 The @code{(guix derivations)} module provides a representation of
7478 derivations as Scheme objects, along with procedures to create and
7479 otherwise manipulate derivations. The lowest-level primitive to create
7480 a derivation is the @code{derivation} procedure:
7482 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
7483 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7484 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
7485 [#:system (%current-system)] [#:references-graphs #f] @
7486 [#:allowed-references #f] [#:disallowed-references #f] @
7487 [#:leaked-env-vars #f] [#:local-build? #f] @
7488 [#:substitutable? #t] [#:properties '()]
7489 Build a derivation with the given arguments, and return the resulting
7490 @code{<derivation>} object.
7492 When @var{hash} and @var{hash-algo} are given, a
7493 @dfn{fixed-output derivation} is created---i.e., one whose result is
7494 known in advance, such as a file download. If, in addition,
7495 @var{recursive?} is true, then that fixed output may be an executable
7496 file or a directory and @var{hash} must be the hash of an archive
7497 containing this output.
7499 When @var{references-graphs} is true, it must be a list of file
7500 name/store path pairs. In that case, the reference graph of each store
7501 path is exported in the build environment in the corresponding file, in
7502 a simple text format.
7504 When @var{allowed-references} is true, it must be a list of store items
7505 or outputs that the derivation's output may refer to. Likewise,
7506 @var{disallowed-references}, if true, must be a list of things the
7507 outputs may @emph{not} refer to.
7509 When @var{leaked-env-vars} is true, it must be a list of strings
7510 denoting environment variables that are allowed to ``leak'' from the
7511 daemon's environment to the build environment. This is only applicable
7512 to fixed-output derivations---i.e., when @var{hash} is true. The main
7513 use is to allow variables such as @code{http_proxy} to be passed to
7514 derivations that download files.
7516 When @var{local-build?} is true, declare that the derivation is not a
7517 good candidate for offloading and should rather be built locally
7518 (@pxref{Daemon Offload Setup}). This is the case for small derivations
7519 where the costs of data transfers would outweigh the benefits.
7521 When @var{substitutable?} is false, declare that substitutes of the
7522 derivation's output should not be used (@pxref{Substitutes}). This is
7523 useful, for instance, when building packages that capture details of the
7524 host CPU instruction set.
7526 @var{properties} must be an association list describing ``properties'' of the
7527 derivation. It is kept as-is, uninterpreted, in the derivation.
7531 Here's an example with a shell script as its builder, assuming
7532 @var{store} is an open connection to the daemon, and @var{bash} points
7533 to a Bash executable in the store:
7536 (use-modules (guix utils)
7540 (let ((builder ; add the Bash script to the store
7541 (add-text-to-store store "my-builder.sh"
7542 "echo hello world > $out\n" '())))
7543 (derivation store "foo"
7544 bash `("-e" ,builder)
7545 #:inputs `((,bash) (,builder))
7546 #:env-vars '(("HOME" . "/homeless"))))
7547 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
7550 As can be guessed, this primitive is cumbersome to use directly. A
7551 better approach is to write build scripts in Scheme, of course! The
7552 best course of action for that is to write the build code as a
7553 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
7554 information, @pxref{G-Expressions}.
7556 Once upon a time, @code{gexp->derivation} did not exist and constructing
7557 derivations with build code written in Scheme was achieved with
7558 @code{build-expression->derivation}, documented below. This procedure
7559 is now deprecated in favor of the much nicer @code{gexp->derivation}.
7561 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
7562 @var{name} @var{exp} @
7563 [#:system (%current-system)] [#:inputs '()] @
7564 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7565 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7566 [#:references-graphs #f] [#:allowed-references #f] @
7567 [#:disallowed-references #f] @
7568 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
7569 Return a derivation that executes Scheme expression @var{exp} as a
7570 builder for derivation @var{name}. @var{inputs} must be a list of
7571 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
7572 @code{"out"} is assumed. @var{modules} is a list of names of Guile
7573 modules from the current search path to be copied in the store,
7574 compiled, and made available in the load path during the execution of
7575 @var{exp}---e.g., @code{((guix build utils) (guix build
7576 gnu-build-system))}.
7578 @var{exp} is evaluated in an environment where @code{%outputs} is bound
7579 to a list of output/path pairs, and where @code{%build-inputs} is bound
7580 to a list of string/output-path pairs made from @var{inputs}.
7581 Optionally, @var{env-vars} is a list of string pairs specifying the name
7582 and value of environment variables visible to the builder. The builder
7583 terminates by passing the result of @var{exp} to @code{exit}; thus, when
7584 @var{exp} returns @code{#f}, the build is considered to have failed.
7586 @var{exp} is built using @var{guile-for-build} (a derivation). When
7587 @var{guile-for-build} is omitted or is @code{#f}, the value of the
7588 @code{%guile-for-build} fluid is used instead.
7590 See the @code{derivation} procedure for the meaning of
7591 @var{references-graphs}, @var{allowed-references},
7592 @var{disallowed-references}, @var{local-build?}, and
7593 @var{substitutable?}.
7597 Here's an example of a single-output derivation that creates a directory
7598 containing one file:
7601 (let ((builder '(let ((out (assoc-ref %outputs "out")))
7602 (mkdir out) ; create /gnu/store/@dots{}-goo
7603 (call-with-output-file (string-append out "/test")
7605 (display '(hello guix) p))))))
7606 (build-expression->derivation store "goo" builder))
7608 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
7612 @node The Store Monad
7613 @section The Store Monad
7617 The procedures that operate on the store described in the previous
7618 sections all take an open connection to the build daemon as their first
7619 argument. Although the underlying model is functional, they either have
7620 side effects or depend on the current state of the store.
7622 The former is inconvenient: the connection to the build daemon has to be
7623 carried around in all those functions, making it impossible to compose
7624 functions that do not take that parameter with functions that do. The
7625 latter can be problematic: since store operations have side effects
7626 and/or depend on external state, they have to be properly sequenced.
7628 @cindex monadic values
7629 @cindex monadic functions
7630 This is where the @code{(guix monads)} module comes in. This module
7631 provides a framework for working with @dfn{monads}, and a particularly
7632 useful monad for our uses, the @dfn{store monad}. Monads are a
7633 construct that allows two things: associating ``context'' with values
7634 (in our case, the context is the store), and building sequences of
7635 computations (here computations include accesses to the store). Values
7636 in a monad---values that carry this additional context---are called
7637 @dfn{monadic values}; procedures that return such values are called
7638 @dfn{monadic procedures}.
7640 Consider this ``normal'' procedure:
7643 (define (sh-symlink store)
7644 ;; Return a derivation that symlinks the 'bash' executable.
7645 (let* ((drv (package-derivation store bash))
7646 (out (derivation->output-path drv))
7647 (sh (string-append out "/bin/bash")))
7648 (build-expression->derivation store "sh"
7649 `(symlink ,sh %output))))
7652 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
7653 as a monadic function:
7656 (define (sh-symlink)
7657 ;; Same, but return a monadic value.
7658 (mlet %store-monad ((drv (package->derivation bash)))
7659 (gexp->derivation "sh"
7660 #~(symlink (string-append #$drv "/bin/bash")
7664 There are several things to note in the second version: the @code{store}
7665 parameter is now implicit and is ``threaded'' in the calls to the
7666 @code{package->derivation} and @code{gexp->derivation} monadic
7667 procedures, and the monadic value returned by @code{package->derivation}
7668 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
7670 As it turns out, the call to @code{package->derivation} can even be
7671 omitted since it will take place implicitly, as we will see later
7672 (@pxref{G-Expressions}):
7675 (define (sh-symlink)
7676 (gexp->derivation "sh"
7677 #~(symlink (string-append #$bash "/bin/bash")
7682 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
7683 @c for the funny quote.
7684 Calling the monadic @code{sh-symlink} has no effect. As someone once
7685 said, ``you exit a monad like you exit a building on fire: by running''.
7686 So, to exit the monad and get the desired effect, one must use
7687 @code{run-with-store}:
7690 (run-with-store (open-connection) (sh-symlink))
7691 @result{} /gnu/store/...-sh-symlink
7694 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
7695 new ``meta-commands'' to make it easier to deal with monadic procedures:
7696 @code{run-in-store}, and @code{enter-store-monad}. The former is used
7697 to ``run'' a single monadic value through the store:
7700 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
7701 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7704 The latter enters a recursive REPL, where all the return values are
7705 automatically run through the store:
7708 scheme@@(guile-user)> ,enter-store-monad
7709 store-monad@@(guile-user) [1]> (package->derivation hello)
7710 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7711 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
7712 $3 = "/gnu/store/@dots{}-foo"
7713 store-monad@@(guile-user) [1]> ,q
7714 scheme@@(guile-user)>
7718 Note that non-monadic values cannot be returned in the
7719 @code{store-monad} REPL.
7721 The main syntactic forms to deal with monads in general are provided by
7722 the @code{(guix monads)} module and are described below.
7724 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
7725 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
7729 @deffn {Scheme Syntax} return @var{val}
7730 Return a monadic value that encapsulates @var{val}.
7733 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
7734 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
7735 procedures @var{mproc}@dots{}@footnote{This operation is commonly
7736 referred to as ``bind'', but that name denotes an unrelated procedure in
7737 Guile. Thus we use this somewhat cryptic symbol inherited from the
7738 Haskell language.}. There can be one @var{mproc} or several of them, as
7743 (with-monad %state-monad
7745 (lambda (x) (return (+ 1 x)))
7746 (lambda (x) (return (* 2 x)))))
7750 @result{} some-state
7754 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
7756 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
7758 Bind the variables @var{var} to the monadic values @var{mval} in
7759 @var{body}, which is a sequence of expressions. As with the bind
7760 operator, this can be thought of as ``unpacking'' the raw, non-monadic
7761 value ``contained'' in @var{mval} and making @var{var} refer to that
7762 raw, non-monadic value within the scope of the @var{body}. The form
7763 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
7764 @var{val}, as per @code{let}. The binding operations occur in sequence
7765 from left to right. The last expression of @var{body} must be a monadic
7766 expression, and its result will become the result of the @code{mlet} or
7767 @code{mlet*} when run in the @var{monad}.
7769 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
7770 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
7773 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
7774 Bind @var{mexp} and the following monadic expressions in sequence,
7775 returning the result of the last expression. Every expression in the
7776 sequence must be a monadic expression.
7778 This is akin to @code{mlet}, except that the return values of the
7779 monadic expressions are ignored. In that sense, it is analogous to
7780 @code{begin}, but applied to monadic expressions.
7783 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
7784 When @var{condition} is true, evaluate the sequence of monadic
7785 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7786 @var{condition} is false, return @code{*unspecified*} in the current
7787 monad. Every expression in the sequence must be a monadic expression.
7790 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
7791 When @var{condition} is false, evaluate the sequence of monadic
7792 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7793 @var{condition} is true, return @code{*unspecified*} in the current
7794 monad. Every expression in the sequence must be a monadic expression.
7798 The @code{(guix monads)} module provides the @dfn{state monad}, which
7799 allows an additional value---the state---to be @emph{threaded} through
7800 monadic procedure calls.
7802 @defvr {Scheme Variable} %state-monad
7803 The state monad. Procedures in the state monad can access and change
7804 the state that is threaded.
7806 Consider the example below. The @code{square} procedure returns a value
7807 in the state monad. It returns the square of its argument, but also
7808 increments the current state value:
7812 (mlet %state-monad ((count (current-state)))
7813 (mbegin %state-monad
7814 (set-current-state (+ 1 count))
7817 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
7822 When ``run'' through @code{%state-monad}, we obtain that additional state
7823 value, which is the number of @code{square} calls.
7826 @deffn {Monadic Procedure} current-state
7827 Return the current state as a monadic value.
7830 @deffn {Monadic Procedure} set-current-state @var{value}
7831 Set the current state to @var{value} and return the previous state as a
7835 @deffn {Monadic Procedure} state-push @var{value}
7836 Push @var{value} to the current state, which is assumed to be a list,
7837 and return the previous state as a monadic value.
7840 @deffn {Monadic Procedure} state-pop
7841 Pop a value from the current state and return it as a monadic value.
7842 The state is assumed to be a list.
7845 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
7846 Run monadic value @var{mval} starting with @var{state} as the initial
7847 state. Return two values: the resulting value, and the resulting state.
7850 The main interface to the store monad, provided by the @code{(guix
7851 store)} module, is as follows.
7853 @defvr {Scheme Variable} %store-monad
7854 The store monad---an alias for @code{%state-monad}.
7856 Values in the store monad encapsulate accesses to the store. When its
7857 effect is needed, a value of the store monad must be ``evaluated'' by
7858 passing it to the @code{run-with-store} procedure (see below).
7861 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
7862 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
7863 open store connection.
7866 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
7867 Return as a monadic value the absolute file name in the store of the file
7868 containing @var{text}, a string. @var{references} is a list of store items that the
7869 resulting text file refers to; it defaults to the empty list.
7872 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
7873 Return as a monadic value the absolute file name in the store of the file
7874 containing @var{data}, a bytevector. @var{references} is a list of store
7875 items that the resulting binary file refers to; it defaults to the empty list.
7878 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
7879 [#:recursive? #t] [#:select? (const #t)]
7880 Return the name of @var{file} once interned in the store. Use
7881 @var{name} as its store name, or the basename of @var{file} if
7882 @var{name} is omitted.
7884 When @var{recursive?} is true, the contents of @var{file} are added
7885 recursively; if @var{file} designates a flat file and @var{recursive?}
7886 is true, its contents are added, and its permission bits are kept.
7888 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7889 @var{stat})} for each directory entry, where @var{file} is the entry's
7890 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7891 entries for which @var{select?} does not return true.
7893 The example below adds a file to the store, under two different names:
7896 (run-with-store (open-connection)
7897 (mlet %store-monad ((a (interned-file "README"))
7898 (b (interned-file "README" "LEGU-MIN")))
7899 (return (list a b))))
7901 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
7906 The @code{(guix packages)} module exports the following package-related
7909 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
7910 [#:system (%current-system)] [#:target #f] @
7913 value in the absolute file name of @var{file} within the @var{output}
7914 directory of @var{package}. When @var{file} is omitted, return the name
7915 of the @var{output} directory of @var{package}. When @var{target} is
7916 true, use it as a cross-compilation target triplet.
7918 Note that this procedure does @emph{not} build @var{package}. Thus, the
7919 result might or might not designate an existing file. We recommend not
7920 using this procedure unless you know what you are doing.
7923 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
7924 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7925 @var{target} [@var{system}]
7926 Monadic version of @code{package-derivation} and
7927 @code{package-cross-derivation} (@pxref{Defining Packages}).
7932 @section G-Expressions
7934 @cindex G-expression
7935 @cindex build code quoting
7936 So we have ``derivations'', which represent a sequence of build actions
7937 to be performed to produce an item in the store (@pxref{Derivations}).
7938 These build actions are performed when asking the daemon to actually
7939 build the derivations; they are run by the daemon in a container
7940 (@pxref{Invoking guix-daemon}).
7942 @cindex strata of code
7943 It should come as no surprise that we like to write these build actions
7944 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7945 code@footnote{The term @dfn{stratum} in this context was coined by
7946 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7947 Kiselyov, who has written insightful
7948 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7949 on this topic}, refers to this kind of code generation as
7950 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7951 to the daemon, etc.---and the ``build code''---code that actually
7952 performs build actions, such as making directories, invoking
7953 @command{make}, etc.
7955 To describe a derivation and its build actions, one typically needs to
7956 embed build code inside host code. It boils down to manipulating build
7957 code as data, and the homoiconicity of Scheme---code has a direct
7958 representation as data---comes in handy for that. But we need more than
7959 the normal @code{quasiquote} mechanism in Scheme to construct build
7962 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7963 S-expressions adapted to build expressions. G-expressions, or
7964 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7965 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7966 @code{#$}, and @code{#$@@}), which are comparable to
7967 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7968 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7969 GNU Guile Reference Manual}). However, there are major differences:
7973 Gexps are meant to be written to a file and run or manipulated by other
7977 When a high-level object such as a package or derivation is unquoted
7978 inside a gexp, the result is as if its output file name had been
7982 Gexps carry information about the packages or derivations they refer to,
7983 and these dependencies are automatically added as inputs to the build
7984 processes that use them.
7987 @cindex lowering, of high-level objects in gexps
7988 This mechanism is not limited to package and derivation
7989 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7990 derivations or files in the store can be defined,
7991 such that these objects can also be inserted
7992 into gexps. For example, a useful type of high-level objects that can be
7993 inserted in a gexp is ``file-like objects'', which make it easy to
7994 add files to the store and to refer to them in
7995 derivations and such (see @code{local-file} and @code{plain-file}
7998 To illustrate the idea, here is an example of a gexp:
8005 (symlink (string-append #$coreutils "/bin/ls")
8009 This gexp can be passed to @code{gexp->derivation}; we obtain a
8010 derivation that builds a directory containing exactly one symlink to
8011 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
8014 (gexp->derivation "the-thing" build-exp)
8017 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
8018 substituted to the reference to the @var{coreutils} package in the
8019 actual build code, and @var{coreutils} is automatically made an input to
8020 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
8021 output)}) is replaced by a string containing the directory name of the
8022 output of the derivation.
8024 @cindex cross compilation
8025 In a cross-compilation context, it is useful to distinguish between
8026 references to the @emph{native} build of a package---that can run on the
8027 host---versus references to cross builds of a package. To that end, the
8028 @code{#+} plays the same role as @code{#$}, but is a reference to a
8029 native package build:
8032 (gexp->derivation "vi"
8035 (mkdir (string-append #$output "/bin"))
8036 (system* (string-append #+coreutils "/bin/ln")
8038 (string-append #$emacs "/bin/emacs")
8039 (string-append #$output "/bin/vi")))
8040 #:target "aarch64-linux-gnu")
8044 In the example above, the native build of @var{coreutils} is used, so
8045 that @command{ln} can actually run on the host; but then the
8046 cross-compiled build of @var{emacs} is referenced.
8048 @cindex imported modules, for gexps
8049 @findex with-imported-modules
8050 Another gexp feature is @dfn{imported modules}: sometimes you want to be
8051 able to use certain Guile modules from the ``host environment'' in the
8052 gexp, so those modules should be imported in the ``build environment''.
8053 The @code{with-imported-modules} form allows you to express that:
8056 (let ((build (with-imported-modules '((guix build utils))
8058 (use-modules (guix build utils))
8059 (mkdir-p (string-append #$output "/bin"))))))
8060 (gexp->derivation "empty-dir"
8063 (display "success!\n")
8068 In this example, the @code{(guix build utils)} module is automatically
8069 pulled into the isolated build environment of our gexp, such that
8070 @code{(use-modules (guix build utils))} works as expected.
8072 @cindex module closure
8073 @findex source-module-closure
8074 Usually you want the @emph{closure} of the module to be imported---i.e.,
8075 the module itself and all the modules it depends on---rather than just
8076 the module; failing to do that, attempts to use the module will fail
8077 because of missing dependent modules. The @code{source-module-closure}
8078 procedure computes the closure of a module by looking at its source file
8079 headers, which comes in handy in this case:
8082 (use-modules (guix modules)) ;for 'source-module-closure'
8084 (with-imported-modules (source-module-closure
8085 '((guix build utils)
8087 (gexp->derivation "something-with-vms"
8089 (use-modules (guix build utils)
8094 @cindex extensions, for gexps
8095 @findex with-extensions
8096 In the same vein, sometimes you want to import not just pure-Scheme
8097 modules, but also ``extensions'' such as Guile bindings to C libraries
8098 or other ``full-blown'' packages. Say you need the @code{guile-json}
8099 package available on the build side, here's how you would do it:
8102 (use-modules (gnu packages guile)) ;for 'guile-json'
8104 (with-extensions (list guile-json)
8105 (gexp->derivation "something-with-json"
8107 (use-modules (json))
8111 The syntactic form to construct gexps is summarized below.
8113 @deffn {Scheme Syntax} #~@var{exp}
8114 @deffnx {Scheme Syntax} (gexp @var{exp})
8115 Return a G-expression containing @var{exp}. @var{exp} may contain one
8116 or more of the following forms:
8120 @itemx (ungexp @var{obj})
8121 Introduce a reference to @var{obj}. @var{obj} may have one of the
8122 supported types, for example a package or a
8123 derivation, in which case the @code{ungexp} form is replaced by its
8124 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
8126 If @var{obj} is a list, it is traversed and references to supported
8127 objects are substituted similarly.
8129 If @var{obj} is another gexp, its contents are inserted and its
8130 dependencies are added to those of the containing gexp.
8132 If @var{obj} is another kind of object, it is inserted as is.
8134 @item #$@var{obj}:@var{output}
8135 @itemx (ungexp @var{obj} @var{output})
8136 This is like the form above, but referring explicitly to the
8137 @var{output} of @var{obj}---this is useful when @var{obj} produces
8138 multiple outputs (@pxref{Packages with Multiple Outputs}).
8141 @itemx #+@var{obj}:output
8142 @itemx (ungexp-native @var{obj})
8143 @itemx (ungexp-native @var{obj} @var{output})
8144 Same as @code{ungexp}, but produces a reference to the @emph{native}
8145 build of @var{obj} when used in a cross compilation context.
8147 @item #$output[:@var{output}]
8148 @itemx (ungexp output [@var{output}])
8149 Insert a reference to derivation output @var{output}, or to the main
8150 output when @var{output} is omitted.
8152 This only makes sense for gexps passed to @code{gexp->derivation}.
8155 @itemx (ungexp-splicing @var{lst})
8156 Like the above, but splices the contents of @var{lst} inside the
8160 @itemx (ungexp-native-splicing @var{lst})
8161 Like the above, but refers to native builds of the objects listed in
8166 G-expressions created by @code{gexp} or @code{#~} are run-time objects
8167 of the @code{gexp?} type (see below).
8170 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
8171 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
8172 in their execution environment.
8174 Each item in @var{modules} can be the name of a module, such as
8175 @code{(guix build utils)}, or it can be a module name, followed by an
8176 arrow, followed by a file-like object:
8179 `((guix build utils)
8181 ((guix config) => ,(scheme-file "config.scm"
8182 #~(define-module @dots{}))))
8186 In the example above, the first two modules are taken from the search
8187 path, and the last one is created from the given file-like object.
8189 This form has @emph{lexical} scope: it has an effect on the gexps
8190 directly defined in @var{body}@dots{}, but not on those defined, say, in
8191 procedures called from @var{body}@dots{}.
8194 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
8195 Mark the gexps defined in @var{body}@dots{} as requiring
8196 @var{extensions} in their build and execution environment.
8197 @var{extensions} is typically a list of package objects such as those
8198 defined in the @code{(gnu packages guile)} module.
8200 Concretely, the packages listed in @var{extensions} are added to the
8201 load path while compiling imported modules in @var{body}@dots{}; they
8202 are also added to the load path of the gexp returned by
8206 @deffn {Scheme Procedure} gexp? @var{obj}
8207 Return @code{#t} if @var{obj} is a G-expression.
8210 G-expressions are meant to be written to disk, either as code building
8211 some derivation, or as plain files in the store. The monadic procedures
8212 below allow you to do that (@pxref{The Store Monad}, for more
8213 information about monads).
8215 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
8216 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
8217 [#:hash #f] [#:hash-algo #f] @
8218 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
8219 [#:module-path @code{%load-path}] @
8220 [#:effective-version "2.2"] @
8221 [#:references-graphs #f] [#:allowed-references #f] @
8222 [#:disallowed-references #f] @
8223 [#:leaked-env-vars #f] @
8224 [#:script-name (string-append @var{name} "-builder")] @
8225 [#:deprecation-warnings #f] @
8226 [#:local-build? #f] [#:substitutable? #t] @
8227 [#:properties '()] [#:guile-for-build #f]
8228 Return a derivation @var{name} that runs @var{exp} (a gexp) with
8229 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
8230 stored in a file called @var{script-name}. When @var{target} is true,
8231 it is used as the cross-compilation target triplet for packages referred
8234 @var{modules} is deprecated in favor of @code{with-imported-modules}.
8236 make @var{modules} available in the evaluation context of @var{exp};
8237 @var{modules} is a list of names of Guile modules searched in
8238 @var{module-path} to be copied in the store, compiled, and made available in
8239 the load path during the execution of @var{exp}---e.g., @code{((guix
8240 build utils) (guix build gnu-build-system))}.
8242 @var{effective-version} determines the string to use when adding extensions of
8243 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
8245 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
8248 When @var{references-graphs} is true, it must be a list of tuples of one of the
8252 (@var{file-name} @var{package})
8253 (@var{file-name} @var{package} @var{output})
8254 (@var{file-name} @var{derivation})
8255 (@var{file-name} @var{derivation} @var{output})
8256 (@var{file-name} @var{store-item})
8259 The right-hand-side of each element of @var{references-graphs} is automatically made
8260 an input of the build process of @var{exp}. In the build environment, each
8261 @var{file-name} contains the reference graph of the corresponding item, in a simple
8264 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
8265 In the latter case, the list denotes store items that the result is allowed to
8266 refer to. Any reference to another store item will lead to a build error.
8267 Similarly for @var{disallowed-references}, which can list items that must not be
8268 referenced by the outputs.
8270 @var{deprecation-warnings} determines whether to show deprecation warnings while
8271 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
8273 The other arguments are as for @code{derivation} (@pxref{Derivations}).
8276 @cindex file-like objects
8277 The @code{local-file}, @code{plain-file}, @code{computed-file},
8278 @code{program-file}, and @code{scheme-file} procedures below return
8279 @dfn{file-like objects}. That is, when unquoted in a G-expression,
8280 these objects lead to a file in the store. Consider this G-expression:
8283 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
8284 #$(local-file "/tmp/my-nscd.conf"))
8287 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
8288 to the store. Once expanded, for instance @i{via}
8289 @code{gexp->derivation}, the G-expression refers to that copy under
8290 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
8291 does not have any effect on what the G-expression does.
8292 @code{plain-file} can be used similarly; it differs in that the file
8293 content is directly passed as a string.
8295 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
8296 [#:recursive? #f] [#:select? (const #t)]
8297 Return an object representing local file @var{file} to add to the store;
8298 this object can be used in a gexp. If @var{file} is a literal string
8299 denoting a relative file name, it is looked up relative to the source
8300 file where it appears; if @var{file} is not a literal string, it is
8301 looked up relative to the current working directory at run time.
8302 @var{file} will be added to the store under @var{name}--by default the
8303 base name of @var{file}.
8305 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
8306 designates a flat file and @var{recursive?} is true, its contents are added, and its
8307 permission bits are kept.
8309 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
8310 @var{stat})} for each directory entry, where @var{file} is the entry's
8311 absolute file name and @var{stat} is the result of @code{lstat}; exclude
8312 entries for which @var{select?} does not return true.
8314 This is the declarative counterpart of the @code{interned-file} monadic
8315 procedure (@pxref{The Store Monad, @code{interned-file}}).
8318 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
8319 Return an object representing a text file called @var{name} with the given
8320 @var{content} (a string or a bytevector) to be added to the store.
8322 This is the declarative counterpart of @code{text-file}.
8325 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
8326 [#:options '(#:local-build? #t)]
8327 Return an object representing the store item @var{name}, a file or
8328 directory computed by @var{gexp}. @var{options}
8329 is a list of additional arguments to pass to @code{gexp->derivation}.
8331 This is the declarative counterpart of @code{gexp->derivation}.
8334 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
8335 [#:guile (default-guile)] [#:module-path %load-path] @
8336 [#:system (%current-system)] [#:target #f]
8337 Return an executable script @var{name} that runs @var{exp} using
8338 @var{guile}, with @var{exp}'s imported modules in its search path.
8339 Look up @var{exp}'s modules in @var{module-path}.
8341 The example below builds a script that simply invokes the @command{ls}
8345 (use-modules (guix gexp) (gnu packages base))
8347 (gexp->script "list-files"
8348 #~(execl #$(file-append coreutils "/bin/ls")
8352 When ``running'' it through the store (@pxref{The Store Monad,
8353 @code{run-with-store}}), we obtain a derivation that produces an
8354 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
8357 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
8359 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
8363 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
8364 [#:guile #f] [#:module-path %load-path]
8365 Return an object representing the executable store item @var{name} that
8366 runs @var{gexp}. @var{guile} is the Guile package used to execute that
8367 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
8369 This is the declarative counterpart of @code{gexp->script}.
8372 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
8373 [#:set-load-path? #t] [#:module-path %load-path] @
8375 [#:guile (default-guile)]
8376 Return a derivation that builds a file @var{name} containing @var{exp}.
8377 When @var{splice?} is true, @var{exp} is considered to be a list of
8378 expressions that will be spliced in the resulting file.
8380 When @var{set-load-path?} is true, emit code in the resulting file to
8381 set @code{%load-path} and @code{%load-compiled-path} to honor
8382 @var{exp}'s imported modules. Look up @var{exp}'s modules in
8385 The resulting file holds references to all the dependencies of @var{exp}
8386 or a subset thereof.
8389 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
8390 [#:splice? #f] [#:set-load-path? #t]
8391 Return an object representing the Scheme file @var{name} that contains
8394 This is the declarative counterpart of @code{gexp->file}.
8397 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
8398 Return as a monadic value a derivation that builds a text file
8399 containing all of @var{text}. @var{text} may list, in addition to
8400 strings, objects of any type that can be used in a gexp: packages,
8401 derivations, local file objects, etc. The resulting store file holds
8402 references to all these.
8404 This variant should be preferred over @code{text-file} anytime the file
8405 to create will reference items from the store. This is typically the
8406 case when building a configuration file that embeds store file names,
8410 (define (profile.sh)
8411 ;; Return the name of a shell script in the store that
8412 ;; initializes the 'PATH' environment variable.
8413 (text-file* "profile.sh"
8414 "export PATH=" coreutils "/bin:"
8415 grep "/bin:" sed "/bin\n"))
8418 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
8419 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
8420 preventing them from being garbage-collected during its lifetime.
8423 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
8424 Return an object representing store file @var{name} containing
8425 @var{text}. @var{text} is a sequence of strings and file-like objects,
8429 (mixed-text-file "profile"
8430 "export PATH=" coreutils "/bin:" grep "/bin")
8433 This is the declarative counterpart of @code{text-file*}.
8436 @deffn {Scheme Procedure} file-union @var{name} @var{files}
8437 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
8438 Each item in @var{files} must be a two-element list where the first element is the
8439 file name to use in the new directory, and the second element is a gexp
8440 denoting the target file. Here's an example:
8444 `(("hosts" ,(plain-file "hosts"
8445 "127.0.0.1 localhost"))
8446 ("bashrc" ,(plain-file "bashrc"
8447 "alias ls='ls --color=auto'"))))
8450 This yields an @code{etc} directory containing these two files.
8453 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
8454 Return a directory that is the union of @var{things}, where @var{things} is a list of
8455 file-like objects denoting directories. For example:
8458 (directory-union "guile+emacs" (list guile emacs))
8461 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
8464 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
8465 Return a file-like object that expands to the concatenation of @var{obj}
8466 and @var{suffix}, where @var{obj} is a lowerable object and each
8467 @var{suffix} is a string.
8469 As an example, consider this gexp:
8472 (gexp->script "run-uname"
8473 #~(system* #$(file-append coreutils
8477 The same effect could be achieved with:
8480 (gexp->script "run-uname"
8481 #~(system* (string-append #$coreutils
8485 There is one difference though: in the @code{file-append} case, the
8486 resulting script contains the absolute file name as a string, whereas in
8487 the second case, the resulting script contains a @code{(string-append
8488 @dots{})} expression to construct the file name @emph{at run time}.
8491 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
8492 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
8493 Bind @var{system} to the currently targeted system---e.g.,
8494 @code{"x86_64-linux"}---within @var{body}.
8496 In the second case, additionally bind @var{target} to the current
8497 cross-compilation target---a GNU triplet such as
8498 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
8501 @code{let-system} is useful in the occasional case where the object
8502 spliced into the gexp depends on the target system, as in this example:
8506 #+(let-system system
8507 (cond ((string-prefix? "armhf-" system)
8508 (file-append qemu "/bin/qemu-system-arm"))
8509 ((string-prefix? "x86_64-" system)
8510 (file-append qemu "/bin/qemu-system-x86_64"))
8513 "-net" "user" #$image)
8517 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
8518 This macro is similar to the @code{parameterize} form for
8519 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
8520 Guile Reference Manual}). The key difference is that it takes effect
8521 when the file-like object returned by @var{exp} is lowered to a
8522 derivation or store item.
8524 A typical use of @code{with-parameters} is to force the system in effect
8528 (with-parameters ((%current-system "i686-linux"))
8532 The example above returns an object that corresponds to the i686 build
8533 of Coreutils, regardless of the current value of @code{%current-system}.
8537 Of course, in addition to gexps embedded in ``host'' code, there are
8538 also modules containing build tools. To make it clear that they are
8539 meant to be used in the build stratum, these modules are kept in the
8540 @code{(guix build @dots{})} name space.
8542 @cindex lowering, of high-level objects in gexps
8543 Internally, high-level objects are @dfn{lowered}, using their compiler,
8544 to either derivations or store items. For instance, lowering a package
8545 yields a derivation, and lowering a @code{plain-file} yields a store
8546 item. This is achieved using the @code{lower-object} monadic procedure.
8548 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
8550 Return as a value in @code{%store-monad} the derivation or store item
8551 corresponding to @var{obj} for @var{system}, cross-compiling for
8552 @var{target} if @var{target} is true. @var{obj} must be an object that
8553 has an associated gexp compiler, such as a @code{<package>}.
8556 @node Invoking guix repl
8557 @section Invoking @command{guix repl}
8559 @cindex REPL, read-eval-print loop, script
8560 The @command{guix repl} command makes it easier to program Guix in Guile
8561 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
8562 programming (@pxref{Using Guile Interactively,,, guile,
8563 GNU Guile Reference Manual}), or by running Guile scripts
8564 (@pxref{Running Guile Scripts,,, guile,
8565 GNU Guile Reference Manual}).
8566 Compared to just launching the @command{guile}
8567 command, @command{guix repl} guarantees that all the Guix modules and all its
8568 dependencies are available in the search path.
8570 The general syntax is:
8573 guix repl @var{options} [@var{file} @var{args}]
8576 When a @var{file} argument is provided, @var{file} is
8577 executed as a Guile scripts:
8580 guix repl my-script.scm
8583 To pass arguments to the script, use @code{--} to prevent them from
8584 being interpreted as arguments to @command{guix repl} itself:
8587 guix repl -- my-script.scm --input=foo.txt
8590 To make a script executable directly from the shell, using the guix
8591 executable that is on the user's search path, add the following two
8592 lines at the top of the script:
8595 @code{#!/usr/bin/env -S guix repl --}
8599 Without a file name argument, a Guile REPL is started:
8603 scheme@@(guile-user)> ,use (gnu packages base)
8604 scheme@@(guile-user)> coreutils
8605 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
8609 In addition, @command{guix repl} implements a simple machine-readable REPL
8610 protocol for use by @code{(guix inferior)}, a facility to interact with
8611 @dfn{inferiors}, separate processes running a potentially different revision
8614 The available options are as follows:
8617 @item --type=@var{type}
8618 @itemx -t @var{type}
8619 Start a REPL of the given @var{TYPE}, which can be one of the following:
8623 This is default, and it spawns a standard full-featured Guile REPL.
8625 Spawn a REPL that uses the machine-readable protocol. This is the protocol
8626 that the @code{(guix inferior)} module speaks.
8629 @item --listen=@var{endpoint}
8630 By default, @command{guix repl} reads from standard input and writes to
8631 standard output. When this option is passed, it will instead listen for
8632 connections on @var{endpoint}. Here are examples of valid options:
8635 @item --listen=tcp:37146
8636 Accept connections on localhost on port 37146.
8638 @item --listen=unix:/tmp/socket
8639 Accept connections on the Unix-domain socket @file{/tmp/socket}.
8642 @item --load-path=@var{directory}
8643 @itemx -L @var{directory}
8644 Add @var{directory} to the front of the package module search path
8645 (@pxref{Package Modules}).
8647 This allows users to define their own packages and make them visible to
8651 Inhibit loading of the @file{~/.guile} file. By default, that
8652 configuration file is loaded when spawning a @code{guile} REPL.
8655 @c *********************************************************************
8659 This section describes Guix command-line utilities. Some of them are
8660 primarily targeted at developers and users who write new package
8661 definitions, while others are more generally useful. They complement
8662 the Scheme programming interface of Guix in a convenient way.
8665 * Invoking guix build:: Building packages from the command line.
8666 * Invoking guix edit:: Editing package definitions.
8667 * Invoking guix download:: Downloading a file and printing its hash.
8668 * Invoking guix hash:: Computing the cryptographic hash of a file.
8669 * Invoking guix import:: Importing package definitions.
8670 * Invoking guix refresh:: Updating package definitions.
8671 * Invoking guix lint:: Finding errors in package definitions.
8672 * Invoking guix size:: Profiling disk usage.
8673 * Invoking guix graph:: Visualizing the graph of packages.
8674 * Invoking guix publish:: Sharing substitutes.
8675 * Invoking guix challenge:: Challenging substitute servers.
8676 * Invoking guix copy:: Copying to and from a remote store.
8677 * Invoking guix container:: Process isolation.
8678 * Invoking guix weather:: Assessing substitute availability.
8679 * Invoking guix processes:: Listing client processes.
8682 @node Invoking guix build
8683 @section Invoking @command{guix build}
8685 @cindex package building
8686 @cindex @command{guix build}
8687 The @command{guix build} command builds packages or derivations and
8688 their dependencies, and prints the resulting store paths. Note that it
8689 does not modify the user's profile---this is the job of the
8690 @command{guix package} command (@pxref{Invoking guix package}). Thus,
8691 it is mainly useful for distribution developers.
8693 The general syntax is:
8696 guix build @var{options} @var{package-or-derivation}@dots{}
8699 As an example, the following command builds the latest versions of Emacs
8700 and of Guile, displays their build logs, and finally displays the
8701 resulting directories:
8704 guix build emacs guile
8707 Similarly, the following command builds all the available packages:
8710 guix build --quiet --keep-going \
8711 `guix package -A | cut -f1,2 --output-delimiter=@@`
8714 @var{package-or-derivation} may be either the name of a package found in
8715 the software distribution such as @code{coreutils} or
8716 @code{coreutils@@8.20}, or a derivation such as
8717 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
8718 package with the corresponding name (and optionally version) is searched
8719 for among the GNU distribution modules (@pxref{Package Modules}).
8721 Alternatively, the @option{--expression} option may be used to specify a
8722 Scheme expression that evaluates to a package; this is useful when
8723 disambiguating among several same-named packages or package variants is
8726 There may be zero or more @var{options}. The available options are
8727 described in the subsections below.
8730 * Common Build Options:: Build options for most commands.
8731 * Package Transformation Options:: Creating variants of packages.
8732 * Additional Build Options:: Options specific to 'guix build'.
8733 * Debugging Build Failures:: Real life packaging experience.
8736 @node Common Build Options
8737 @subsection Common Build Options
8739 A number of options that control the build process are common to
8740 @command{guix build} and other commands that can spawn builds, such as
8741 @command{guix package} or @command{guix archive}. These are the
8746 @item --load-path=@var{directory}
8747 @itemx -L @var{directory}
8748 Add @var{directory} to the front of the package module search path
8749 (@pxref{Package Modules}).
8751 This allows users to define their own packages and make them visible to
8752 the command-line tools.
8756 Keep the build tree of failed builds. Thus, if a build fails, its build
8757 tree is kept under @file{/tmp}, in a directory whose name is shown at
8758 the end of the build log. This is useful when debugging build issues.
8759 @xref{Debugging Build Failures}, for tips and tricks on how to debug
8762 This option implies @option{--no-offload}, and it has no effect when
8763 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
8764 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
8768 Keep going when some of the derivations fail to build; return only once
8769 all the builds have either completed or failed.
8771 The default behavior is to stop as soon as one of the specified
8772 derivations has failed.
8776 Do not build the derivations.
8778 @anchor{fallback-option}
8780 When substituting a pre-built binary fails, fall back to building
8781 packages locally (@pxref{Substitution Failure}).
8783 @item --substitute-urls=@var{urls}
8784 @anchor{client-substitute-urls}
8785 Consider @var{urls} the whitespace-separated list of substitute source
8786 URLs, overriding the default list of URLs of @command{guix-daemon}
8787 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
8789 This means that substitutes may be downloaded from @var{urls}, provided
8790 they are signed by a key authorized by the system administrator
8791 (@pxref{Substitutes}).
8793 When @var{urls} is the empty string, substitutes are effectively
8796 @item --no-substitutes
8797 Do not use substitutes for build products. That is, always build things
8798 locally instead of allowing downloads of pre-built binaries
8799 (@pxref{Substitutes}).
8802 Do not ``graft'' packages. In practice, this means that package updates
8803 available as grafts are not applied. @xref{Security Updates}, for more
8804 information on grafts.
8806 @item --rounds=@var{n}
8807 Build each derivation @var{n} times in a row, and raise an error if
8808 consecutive build results are not bit-for-bit identical.
8810 This is a useful way to detect non-deterministic builds processes.
8811 Non-deterministic build processes are a problem because they make it
8812 practically impossible for users to @emph{verify} whether third-party
8813 binaries are genuine. @xref{Invoking guix challenge}, for more.
8815 Note that, currently, the differing build results are not kept around,
8816 so you will have to manually investigate in case of an error---e.g., by
8817 stashing one of the build results with @code{guix archive --export}
8818 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
8822 Do not use offload builds to other machines (@pxref{Daemon Offload
8823 Setup}). That is, always build things locally instead of offloading
8824 builds to remote machines.
8826 @item --max-silent-time=@var{seconds}
8827 When the build or substitution process remains silent for more than
8828 @var{seconds}, terminate it and report a build failure.
8830 By default, the daemon's setting is honored (@pxref{Invoking
8831 guix-daemon, @option{--max-silent-time}}).
8833 @item --timeout=@var{seconds}
8834 Likewise, when the build or substitution process lasts for more than
8835 @var{seconds}, terminate it and report a build failure.
8837 By default, the daemon's setting is honored (@pxref{Invoking
8838 guix-daemon, @option{--timeout}}).
8840 @c Note: This option is actually not part of %standard-build-options but
8841 @c most programs honor it.
8842 @cindex verbosity, of the command-line tools
8843 @cindex build logs, verbosity
8844 @item -v @var{level}
8845 @itemx --verbosity=@var{level}
8846 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
8847 output is produced, 1 is for quiet output, and 2 shows all the build log
8848 output on standard error.
8850 @item --cores=@var{n}
8852 Allow the use of up to @var{n} CPU cores for the build. The special
8853 value @code{0} means to use as many CPU cores as available.
8855 @item --max-jobs=@var{n}
8857 Allow at most @var{n} build jobs in parallel. @xref{Invoking
8858 guix-daemon, @option{--max-jobs}}, for details about this option and the
8859 equivalent @command{guix-daemon} option.
8861 @item --debug=@var{level}
8862 Produce debugging output coming from the build daemon. @var{level} must be an
8863 integer between 0 and 5; higher means more verbose output. Setting a level of
8864 4 or more may be helpful when debugging setup issues with the build daemon.
8868 Behind the scenes, @command{guix build} is essentially an interface to
8869 the @code{package-derivation} procedure of the @code{(guix packages)}
8870 module, and to the @code{build-derivations} procedure of the @code{(guix
8871 derivations)} module.
8873 In addition to options explicitly passed on the command line,
8874 @command{guix build} and other @command{guix} commands that support
8875 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
8877 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
8878 Users can define this variable to a list of command line options that
8879 will automatically be used by @command{guix build} and other
8880 @command{guix} commands that can perform builds, as in the example
8884 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
8887 These options are parsed independently, and the result is appended to
8888 the parsed command-line options.
8892 @node Package Transformation Options
8893 @subsection Package Transformation Options
8895 @cindex package variants
8896 Another set of command-line options supported by @command{guix build}
8897 and also @command{guix package} are @dfn{package transformation
8898 options}. These are options that make it possible to define @dfn{package
8899 variants}---for instance, packages built from different source code.
8900 This is a convenient way to create customized packages on the fly
8901 without having to type in the definitions of package variants
8902 (@pxref{Defining Packages}).
8906 @item --with-source=@var{source}
8907 @itemx --with-source=@var{package}=@var{source}
8908 @itemx --with-source=@var{package}@@@var{version}=@var{source}
8909 Use @var{source} as the source of @var{package}, and @var{version} as
8911 @var{source} must be a file name or a URL, as for @command{guix
8912 download} (@pxref{Invoking guix download}).
8914 When @var{package} is omitted,
8915 it is taken to be the package name specified on the
8916 command line that matches the base of @var{source}---e.g.,
8917 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
8918 package is @code{guile}.
8920 Likewise, when @var{version} is omitted, the version string is inferred from
8921 @var{source}; in the previous example, it is @code{2.0.10}.
8923 This option allows users to try out versions of packages other than the
8924 one provided by the distribution. The example below downloads
8925 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
8926 the @code{ed} package:
8929 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
8932 As a developer, @option{--with-source} makes it easy to test release
8936 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
8939 @dots{} or to build from a checkout in a pristine environment:
8942 $ git clone git://git.sv.gnu.org/guix.git
8943 $ guix build guix --with-source=guix@@1.0=./guix
8946 @item --with-input=@var{package}=@var{replacement}
8947 Replace dependency on @var{package} by a dependency on
8948 @var{replacement}. @var{package} must be a package name, and
8949 @var{replacement} must be a package specification such as @code{guile}
8950 or @code{guile@@1.8}.
8952 For instance, the following command builds Guix, but replaces its
8953 dependency on the current stable version of Guile with a dependency on
8954 the legacy version of Guile, @code{guile@@2.0}:
8957 guix build --with-input=guile=guile@@2.0 guix
8960 This is a recursive, deep replacement. So in this example, both
8961 @code{guix} and its dependency @code{guile-json} (which also depends on
8962 @code{guile}) get rebuilt against @code{guile@@2.0}.
8964 This is implemented using the @code{package-input-rewriting} Scheme
8965 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
8967 @item --with-graft=@var{package}=@var{replacement}
8968 This is similar to @option{--with-input} but with an important difference:
8969 instead of rebuilding the whole dependency chain, @var{replacement} is
8970 built and then @dfn{grafted} onto the binaries that were initially
8971 referring to @var{package}. @xref{Security Updates}, for more
8972 information on grafts.
8974 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
8975 and all its dependencies, replacing references to the version of GnuTLS
8976 they currently refer to:
8979 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
8982 This has the advantage of being much faster than rebuilding everything.
8983 But there is a caveat: it works if and only if @var{package} and
8984 @var{replacement} are strictly compatible---for example, if they provide
8985 a library, the application binary interface (ABI) of those libraries
8986 must be compatible. If @var{replacement} is somehow incompatible with
8987 @var{package}, then the resulting package may be unusable. Use with
8990 @item --with-git-url=@var{package}=@var{url}
8991 @cindex Git, using the latest commit
8992 @cindex latest commit, building
8993 Build @var{package} from the latest commit of the @code{master} branch of the
8994 Git repository at @var{url}. Git sub-modules of the repository are fetched,
8997 For example, the following command builds the NumPy Python library against the
8998 latest commit of the master branch of Python itself:
9001 guix build python-numpy \
9002 --with-git-url=python=https://github.com/python/cpython
9005 This option can also be combined with @option{--with-branch} or
9006 @option{--with-commit} (see below).
9008 @cindex continuous integration
9009 Obviously, since it uses the latest commit of the given branch, the result of
9010 such a command varies over time. Nevertheless it is a convenient way to
9011 rebuild entire software stacks against the latest commit of one or more
9012 packages. This is particularly useful in the context of continuous
9015 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
9016 consecutive accesses to the same repository. You may want to clean it up once
9017 in a while to save disk space.
9019 @item --with-branch=@var{package}=@var{branch}
9020 Build @var{package} from the latest commit of @var{branch}. If the
9021 @code{source} field of @var{package} is an origin with the @code{git-fetch}
9022 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
9023 repository URL is taken from that @code{source}. Otherwise you have to use
9024 @option{--with-git-url} to specify the URL of the Git repository.
9026 For instance, the following command builds @code{guile-sqlite3} from the
9027 latest commit of its @code{master} branch, and then builds @code{guix} (which
9028 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
9029 specific @code{guile-sqlite3} build:
9032 guix build --with-branch=guile-sqlite3=master cuirass
9035 @item --with-commit=@var{package}=@var{commit}
9036 This is similar to @option{--with-branch}, except that it builds from
9037 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
9038 Git commit SHA1 identifier or a tag.
9041 @node Additional Build Options
9042 @subsection Additional Build Options
9044 The command-line options presented below are specific to @command{guix
9051 Build quietly, without displaying the build log; this is equivalent to
9052 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
9053 (or similar) and can always be retrieved using the @option{--log-file} option.
9055 @item --file=@var{file}
9056 @itemx -f @var{file}
9057 Build the package, derivation, or other file-like object that the code within
9058 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
9060 As an example, @var{file} might contain a package definition like this
9061 (@pxref{Defining Packages}):
9064 @include package-hello.scm
9067 The @var{file} may also contain a JSON representation of one or more
9068 package definitions. Running @code{guix build -f} on @file{hello.json}
9069 with the following contents would result in building the packages
9070 @code{myhello} and @code{greeter}:
9073 @verbatiminclude package-hello.json
9076 @item --manifest=@var{manifest}
9077 @itemx -m @var{manifest}
9078 Build all packages listed in the given @var{manifest}
9079 (@pxref{profile-manifest, @option{--manifest}}).
9081 @item --expression=@var{expr}
9082 @itemx -e @var{expr}
9083 Build the package or derivation @var{expr} evaluates to.
9085 For example, @var{expr} may be @code{(@@ (gnu packages guile)
9086 guile-1.8)}, which unambiguously designates this specific variant of
9087 version 1.8 of Guile.
9089 Alternatively, @var{expr} may be a G-expression, in which case it is used
9090 as a build program passed to @code{gexp->derivation}
9091 (@pxref{G-Expressions}).
9093 Lastly, @var{expr} may refer to a zero-argument monadic procedure
9094 (@pxref{The Store Monad}). The procedure must return a derivation as a
9095 monadic value, which is then passed through @code{run-with-store}.
9099 Build the source derivations of the packages, rather than the packages
9102 For instance, @code{guix build -S gcc} returns something like
9103 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
9106 The returned source tarball is the result of applying any patches and
9107 code snippets specified in the package @code{origin} (@pxref{Defining
9110 Note that @command{guix build -S} compiles the sources only of the
9111 specified packages. They do not include the sources of statically
9112 linked dependencies and by themselves are insufficient for reproducing
9116 Fetch and return the source of @var{package-or-derivation} and all their
9117 dependencies, recursively. This is a handy way to obtain a local copy
9118 of all the source code needed to build @var{packages}, allowing you to
9119 eventually build them even without network access. It is an extension
9120 of the @option{--source} option and can accept one of the following
9121 optional argument values:
9125 This value causes the @option{--sources} option to behave in the same way
9126 as the @option{--source} option.
9129 Build the source derivations of all packages, including any source that
9130 might be listed as @code{inputs}. This is the default value.
9133 $ guix build --sources tzdata
9134 The following derivations will be built:
9135 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
9136 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
9140 Build the source derivations of all packages, as well of all transitive
9141 inputs to the packages. This can be used e.g.@: to
9142 prefetch package source for later offline building.
9145 $ guix build --sources=transitive tzdata
9146 The following derivations will be built:
9147 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
9148 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
9149 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
9150 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
9151 /gnu/store/@dots{}-make-4.1.tar.xz.drv
9152 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
9158 @item --system=@var{system}
9159 @itemx -s @var{system}
9160 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
9161 the system type of the build host. The @command{guix build} command allows
9162 you to repeat this option several times, in which case it builds for all the
9163 specified systems; other commands ignore extraneous @option{-s} options.
9166 The @option{--system} flag is for @emph{native} compilation and must not
9167 be confused with cross-compilation. See @option{--target} below for
9168 information on cross-compilation.
9171 An example use of this is on Linux-based systems, which can emulate
9172 different personalities. For instance, passing
9173 @option{--system=i686-linux} on an @code{x86_64-linux} system or
9174 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
9175 you to build packages in a complete 32-bit environment.
9178 Building for an @code{armhf-linux} system is unconditionally enabled on
9179 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
9180 allow for this functionality, notably the ThunderX.
9183 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
9184 is enabled (@pxref{Virtualization Services,
9185 @code{qemu-binfmt-service-type}}), you can build for any system for
9186 which a QEMU @code{binfmt_misc} handler is installed.
9188 Builds for a system other than that of the machine you are using can
9189 also be offloaded to a remote machine of the right architecture.
9190 @xref{Daemon Offload Setup}, for more information on offloading.
9192 @item --target=@var{triplet}
9193 @cindex cross-compilation
9194 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
9195 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
9196 configuration triplets,, autoconf, Autoconf}).
9198 @anchor{build-check}
9200 @cindex determinism, checking
9201 @cindex reproducibility, checking
9202 Rebuild @var{package-or-derivation}, which are already available in the
9203 store, and raise an error if the build results are not bit-for-bit
9206 This mechanism allows you to check whether previously installed
9207 substitutes are genuine (@pxref{Substitutes}), or whether the build result
9208 of a package is deterministic. @xref{Invoking guix challenge}, for more
9209 background information and tools.
9211 When used in conjunction with @option{--keep-failed}, the differing
9212 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
9213 This makes it easy to look for differences between the two results.
9216 @cindex repairing store items
9217 @cindex corruption, recovering from
9218 Attempt to repair the specified store items, if they are corrupt, by
9219 re-downloading or rebuilding them.
9221 This operation is not atomic and thus restricted to @code{root}.
9225 Return the derivation paths, not the output paths, of the given
9228 @item --root=@var{file}
9229 @itemx -r @var{file}
9230 @cindex GC roots, adding
9231 @cindex garbage collector roots, adding
9232 Make @var{file} a symlink to the result, and register it as a garbage
9235 Consequently, the results of this @command{guix build} invocation are
9236 protected from garbage collection until @var{file} is removed. When
9237 that option is omitted, build results are eligible for garbage
9238 collection as soon as the build completes. @xref{Invoking guix gc}, for
9242 @cindex build logs, access
9243 Return the build log file names or URLs for the given
9244 @var{package-or-derivation}, or raise an error if build logs are
9247 This works regardless of how packages or derivations are specified. For
9248 instance, the following invocations are equivalent:
9251 guix build --log-file `guix build -d guile`
9252 guix build --log-file `guix build guile`
9253 guix build --log-file guile
9254 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
9257 If a log is unavailable locally, and unless @option{--no-substitutes} is
9258 passed, the command looks for a corresponding log on one of the
9259 substitute servers (as specified with @option{--substitute-urls}).
9261 So for instance, imagine you want to see the build log of GDB on MIPS,
9262 but you are actually on an @code{x86_64} machine:
9265 $ guix build --log-file gdb -s aarch64-linux
9266 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
9269 You can freely access a huge library of build logs!
9272 @node Debugging Build Failures
9273 @subsection Debugging Build Failures
9275 @cindex build failures, debugging
9276 When defining a new package (@pxref{Defining Packages}), you will
9277 probably find yourself spending some time debugging and tweaking the
9278 build until it succeeds. To do that, you need to operate the build
9279 commands yourself in an environment as close as possible to the one the
9282 To that end, the first thing to do is to use the @option{--keep-failed}
9283 or @option{-K} option of @command{guix build}, which will keep the
9284 failed build tree in @file{/tmp} or whatever directory you specified as
9285 @env{TMPDIR} (@pxref{Invoking guix build, @option{--keep-failed}}).
9287 From there on, you can @command{cd} to the failed build tree and source
9288 the @file{environment-variables} file, which contains all the
9289 environment variable definitions that were in place when the build
9290 failed. So let's say you're debugging a build failure in package
9291 @code{foo}; a typical session would look like this:
9295 @dots{} @i{build fails}
9296 $ cd /tmp/guix-build-foo.drv-0
9297 $ source ./environment-variables
9301 Now, you can invoke commands as if you were the daemon (almost) and
9302 troubleshoot your build process.
9304 Sometimes it happens that, for example, a package's tests pass when you
9305 run them manually but they fail when the daemon runs them. This can
9306 happen because the daemon runs builds in containers where, unlike in our
9307 environment above, network access is missing, @file{/bin/sh} does not
9308 exist, etc. (@pxref{Build Environment Setup}).
9310 In such cases, you may need to run inspect the build process from within
9311 a container similar to the one the build daemon creates:
9316 $ cd /tmp/guix-build-foo.drv-0
9317 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
9318 [env]# source ./environment-variables
9322 Here, @command{guix environment -C} creates a container and spawns a new
9323 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
9324 strace gdb} part adds the @command{strace} and @command{gdb} commands to
9325 the container, which you may find handy while debugging. The
9326 @option{--no-grafts} option makes sure we get the exact same
9327 environment, with ungrafted packages (@pxref{Security Updates}, for more
9330 To get closer to a container like that used by the build daemon, we can
9331 remove @file{/bin/sh}:
9337 (Don't worry, this is harmless: this is all happening in the throw-away
9338 container created by @command{guix environment}.)
9340 The @command{strace} command is probably not in the search path, but we
9344 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
9347 In this way, not only you will have reproduced the environment variables
9348 the daemon uses, you will also be running the build process in a container
9349 similar to the one the daemon uses.
9352 @node Invoking guix edit
9353 @section Invoking @command{guix edit}
9355 @cindex @command{guix edit}
9356 @cindex package definition, editing
9357 So many packages, so many source files! The @command{guix edit} command
9358 facilitates the life of users and packagers by pointing their editor at
9359 the source file containing the definition of the specified packages.
9363 guix edit gcc@@4.9 vim
9367 launches the program specified in the @env{VISUAL} or in the
9368 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
9371 If you are using a Guix Git checkout (@pxref{Building from Git}), or
9372 have created your own packages on @env{GUIX_PACKAGE_PATH}
9373 (@pxref{Package Modules}), you will be able to edit the package
9374 recipes. In other cases, you will be able to examine the read-only recipes
9375 for packages currently in the store.
9377 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
9378 @option{--load-path=@var{directory}} (or in short @option{-L
9379 @var{directory}}) allows you to add @var{directory} to the front of the
9380 package module search path and so make your own packages visible.
9382 @node Invoking guix download
9383 @section Invoking @command{guix download}
9385 @cindex @command{guix download}
9386 @cindex downloading package sources
9387 When writing a package definition, developers typically need to download
9388 a source tarball, compute its SHA256 hash, and write that
9389 hash in the package definition (@pxref{Defining Packages}). The
9390 @command{guix download} tool helps with this task: it downloads a file
9391 from the given URI, adds it to the store, and prints both its file name
9392 in the store and its SHA256 hash.
9394 The fact that the downloaded file is added to the store saves bandwidth:
9395 when the developer eventually tries to build the newly defined package
9396 with @command{guix build}, the source tarball will not have to be
9397 downloaded again because it is already in the store. It is also a
9398 convenient way to temporarily stash files, which may be deleted
9399 eventually (@pxref{Invoking guix gc}).
9401 The @command{guix download} command supports the same URIs as used in
9402 package definitions. In particular, it supports @code{mirror://} URIs.
9403 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
9404 Guile bindings for GnuTLS are available in the user's environment; when
9405 they are not available, an error is raised. @xref{Guile Preparations,
9406 how to install the GnuTLS bindings for Guile,, gnutls-guile,
9407 GnuTLS-Guile}, for more information.
9409 @command{guix download} verifies HTTPS server certificates by loading
9410 the certificates of X.509 authorities from the directory pointed to by
9411 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
9412 Certificates}), unless @option{--no-check-certificate} is used.
9414 The following options are available:
9417 @item --hash=@var{algorithm}
9418 @itemx -H @var{algorithm}
9419 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
9420 hash}, for more information.
9422 @item --format=@var{fmt}
9424 Write the hash in the format specified by @var{fmt}. For more
9425 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
9427 @item --no-check-certificate
9428 Do not validate the X.509 certificates of HTTPS servers.
9430 When using this option, you have @emph{absolutely no guarantee} that you
9431 are communicating with the authentic server responsible for the given
9432 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
9434 @item --output=@var{file}
9435 @itemx -o @var{file}
9436 Save the downloaded file to @var{file} instead of adding it to the
9440 @node Invoking guix hash
9441 @section Invoking @command{guix hash}
9443 @cindex @command{guix hash}
9444 The @command{guix hash} command computes the hash of a file.
9445 It is primarily a convenience tool for anyone contributing to the
9446 distribution: it computes the cryptographic hash of a file, which can be
9447 used in the definition of a package (@pxref{Defining Packages}).
9449 The general syntax is:
9452 guix hash @var{option} @var{file}
9455 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
9456 hash of data read from standard input. @command{guix hash} has the
9461 @item --hash=@var{algorithm}
9462 @itemx -H @var{algorithm}
9463 Compute a hash using the specified @var{algorithm}, @code{sha256} by
9466 @var{algorithm} must the name of a cryptographic hash algorithm
9467 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
9468 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
9471 @item --format=@var{fmt}
9473 Write the hash in the format specified by @var{fmt}.
9475 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
9476 (@code{hex} and @code{hexadecimal} can be used as well).
9478 If the @option{--format} option is not specified, @command{guix hash}
9479 will output the hash in @code{nix-base32}. This representation is used
9480 in the definitions of packages.
9484 Compute the hash on @var{file} recursively.
9486 In this case, the hash is computed on an archive containing @var{file},
9487 including its children if it is a directory. Some of the metadata of
9488 @var{file} is part of the archive; for instance, when @var{file} is a
9489 regular file, the hash is different depending on whether @var{file} is
9490 executable or not. Metadata such as time stamps has no impact on the
9491 hash (@pxref{Invoking guix archive}).
9492 @c FIXME: Replace xref above with xref to an ``Archive'' section when
9497 When combined with @option{--recursive}, exclude version control system
9498 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
9501 As an example, here is how you would compute the hash of a Git checkout,
9502 which is useful when using the @code{git-fetch} method (@pxref{origin
9506 $ git clone http://example.org/foo.git
9512 @node Invoking guix import
9513 @section Invoking @command{guix import}
9515 @cindex importing packages
9516 @cindex package import
9517 @cindex package conversion
9518 @cindex Invoking @command{guix import}
9519 The @command{guix import} command is useful for people who would like to
9520 add a package to the distribution with as little work as
9521 possible---a legitimate demand. The command knows of a few
9522 repositories from which it can ``import'' package metadata. The result
9523 is a package definition, or a template thereof, in the format we know
9524 (@pxref{Defining Packages}).
9526 The general syntax is:
9529 guix import @var{importer} @var{options}@dots{}
9532 @var{importer} specifies the source from which to import package
9533 metadata, and @var{options} specifies a package identifier and other
9534 options specific to @var{importer}.
9536 Some of the importers rely on the ability to run the @command{gpgv} command.
9537 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
9540 Currently, the available ``importers'' are:
9544 Import metadata for the given GNU package. This provides a template
9545 for the latest version of that GNU package, including the hash of its
9546 source tarball, and its canonical synopsis and description.
9548 Additional information such as the package dependencies and its
9549 license needs to be figured out manually.
9551 For example, the following command returns a package definition for
9555 guix import gnu hello
9558 Specific command-line options are:
9561 @item --key-download=@var{policy}
9562 As for @command{guix refresh}, specify the policy to handle missing
9563 OpenPGP keys when verifying the package signature. @xref{Invoking guix
9564 refresh, @option{--key-download}}.
9569 Import metadata from the @uref{https://pypi.python.org/, Python Package
9570 Index}. Information is taken from the JSON-formatted description
9571 available at @code{pypi.python.org} and usually includes all the relevant
9572 information, including package dependencies. For maximum efficiency, it
9573 is recommended to install the @command{unzip} utility, so that the
9574 importer can unzip Python wheels and gather data from them.
9576 The command below imports metadata for the @code{itsdangerous} Python
9580 guix import pypi itsdangerous
9586 Traverse the dependency graph of the given upstream package recursively
9587 and generate package expressions for all those packages that are not yet
9593 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
9594 is taken from the JSON-formatted description available at
9595 @code{rubygems.org} and includes most relevant information, including
9596 runtime dependencies. There are some caveats, however. The metadata
9597 doesn't distinguish between synopses and descriptions, so the same string
9598 is used for both fields. Additionally, the details of non-Ruby
9599 dependencies required to build native extensions is unavailable and left
9600 as an exercise to the packager.
9602 The command below imports metadata for the @code{rails} Ruby package:
9605 guix import gem rails
9611 Traverse the dependency graph of the given upstream package recursively
9612 and generate package expressions for all those packages that are not yet
9618 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
9619 Information is taken from the JSON-formatted metadata provided through
9620 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
9621 relevant information, such as module dependencies. License information
9622 should be checked closely. If Perl is available in the store, then the
9623 @code{corelist} utility will be used to filter core modules out of the
9624 list of dependencies.
9626 The command command below imports metadata for the Acme::Boolean Perl
9630 guix import cpan Acme::Boolean
9635 @cindex Bioconductor
9636 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
9637 central repository for the @uref{https://r-project.org, GNU@tie{}R
9638 statistical and graphical environment}.
9640 Information is extracted from the @file{DESCRIPTION} file of the package.
9642 The command command below imports metadata for the Cairo R package:
9645 guix import cran Cairo
9648 When @option{--recursive} is added, the importer will traverse the
9649 dependency graph of the given upstream package recursively and generate
9650 package expressions for all those packages that are not yet in Guix.
9652 When @option{--archive=bioconductor} is added, metadata is imported from
9653 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
9654 packages for for the analysis and comprehension of high-throughput
9655 genomic data in bioinformatics.
9657 Information is extracted from the @file{DESCRIPTION} file contained in the
9660 The command below imports metadata for the GenomicRanges R package:
9663 guix import cran --archive=bioconductor GenomicRanges
9666 Finally, you can also import R packages that have not yet been published on
9667 CRAN or Bioconductor as long as they are in a git repository. Use
9668 @option{--archive=git} followed by the URL of the git repository:
9671 guix import cran --archive=git https://github.com/immunogenomics/harmony
9677 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
9678 comprehensive TeX archive network for TeX packages that are part of the
9679 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
9681 Information about the package is obtained through the XML API provided
9682 by CTAN, while the source code is downloaded from the SVN repository of
9683 the Tex Live project. This is done because the CTAN does not keep
9686 The command command below imports metadata for the @code{fontspec}
9690 guix import texlive fontspec
9693 When @option{--archive=@var{directory}} is added, the source code is
9694 downloaded not from the @file{latex} sub-directory of the
9695 @file{texmf-dist/source} tree in the TeX Live SVN repository, but from
9696 the specified sibling @var{directory} under the same root.
9698 The command below imports metadata for the @code{ifxetex} package from
9699 CTAN while fetching the sources from the directory
9700 @file{texmf/source/generic}:
9703 guix import texlive --archive=generic ifxetex
9707 @cindex JSON, import
9708 Import package metadata from a local JSON file. Consider the following
9709 example package definition in JSON format:
9715 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
9716 "build-system": "gnu",
9717 "home-page": "https://www.gnu.org/software/hello/",
9718 "synopsis": "Hello, GNU world: An example GNU package",
9719 "description": "GNU Hello prints a greeting.",
9720 "license": "GPL-3.0+",
9721 "native-inputs": ["gettext"]
9725 The field names are the same as for the @code{<package>} record
9726 (@xref{Defining Packages}). References to other packages are provided
9727 as JSON lists of quoted package specification strings such as
9728 @code{guile} or @code{guile@@2.0}.
9730 The importer also supports a more explicit source definition using the
9731 common fields for @code{<origin>} records:
9737 "method": "url-fetch",
9738 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
9740 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
9747 The command below reads metadata from the JSON file @code{hello.json}
9748 and outputs a package expression:
9751 guix import json hello.json
9755 Import metadata from a local copy of the source of the
9756 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
9757 relies on the @command{nix-instantiate} command of
9758 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
9759 typically written in a mixture of Nix-language and Bash code. This
9760 command only imports the high-level package structure that is written in
9761 the Nix language. It normally includes all the basic fields of a
9764 When importing a GNU package, the synopsis and descriptions are replaced
9765 by their canonical upstream variant.
9767 Usually, you will first need to do:
9770 export NIX_REMOTE=daemon
9774 so that @command{nix-instantiate} does not try to open the Nix database.
9776 As an example, the command below imports the package definition of
9777 LibreOffice (more precisely, it imports the definition of the package
9778 bound to the @code{libreoffice} top-level attribute):
9781 guix import nix ~/path/to/nixpkgs libreoffice
9786 Import metadata from the Haskell community's central package archive
9787 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
9788 Cabal files and includes all the relevant information, including package
9791 Specific command-line options are:
9796 Read a Cabal file from standard input.
9797 @item --no-test-dependencies
9799 Do not include dependencies required only by the test suites.
9800 @item --cabal-environment=@var{alist}
9801 @itemx -e @var{alist}
9802 @var{alist} is a Scheme alist defining the environment in which the
9803 Cabal conditionals are evaluated. The accepted keys are: @code{os},
9804 @code{arch}, @code{impl} and a string representing the name of a flag.
9805 The value associated with a flag has to be either the symbol
9806 @code{true} or @code{false}. The value associated with other keys
9807 has to conform to the Cabal file format definition. The default value
9808 associated with the keys @code{os}, @code{arch} and @code{impl} is
9809 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
9812 Traverse the dependency graph of the given upstream package recursively
9813 and generate package expressions for all those packages that are not yet
9817 The command below imports metadata for the latest version of the
9818 HTTP Haskell package without including test dependencies and
9819 specifying the value of the flag @samp{network-uri} as @code{false}:
9822 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
9825 A specific package version may optionally be specified by following the
9826 package name by an at-sign and a version number as in the following example:
9829 guix import hackage mtl@@2.1.3.1
9834 The @code{stackage} importer is a wrapper around the @code{hackage} one.
9835 It takes a package name, looks up the package version included in a
9836 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
9837 release and uses the @code{hackage} importer to retrieve its metadata.
9838 Note that it is up to you to select an LTS release compatible with the
9839 GHC compiler used by Guix.
9841 Specific command-line options are:
9844 @item --no-test-dependencies
9846 Do not include dependencies required only by the test suites.
9847 @item --lts-version=@var{version}
9848 @itemx -l @var{version}
9849 @var{version} is the desired LTS release version. If omitted the latest
9853 Traverse the dependency graph of the given upstream package recursively
9854 and generate package expressions for all those packages that are not yet
9858 The command below imports metadata for the HTTP Haskell package
9859 included in the LTS Stackage release version 7.18:
9862 guix import stackage --lts-version=7.18 HTTP
9867 Import metadata from an Emacs Lisp Package Archive (ELPA) package
9868 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9870 Specific command-line options are:
9873 @item --archive=@var{repo}
9874 @itemx -a @var{repo}
9875 @var{repo} identifies the archive repository from which to retrieve the
9876 information. Currently the supported repositories and their identifiers
9880 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
9881 identifier. This is the default.
9883 Packages from @code{elpa.gnu.org} are signed with one of the keys
9884 contained in the GnuPG keyring at
9885 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
9886 @code{emacs} package (@pxref{Package Installation, ELPA package
9887 signatures,, emacs, The GNU Emacs Manual}).
9890 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
9891 @code{melpa-stable} identifier.
9894 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
9900 Traverse the dependency graph of the given upstream package recursively
9901 and generate package expressions for all those packages that are not yet
9907 Import metadata from the crates.io Rust package repository
9908 @uref{https://crates.io, crates.io}, as in this example:
9911 guix import crate blake2-rfc
9914 The crate importer also allows you to specify a version string:
9917 guix import crate constant-time-eq@@0.1.0
9920 Additional options include:
9925 Traverse the dependency graph of the given upstream package recursively
9926 and generate package expressions for all those packages that are not yet
9933 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
9934 repository used by the OCaml community.
9937 The structure of the @command{guix import} code is modular. It would be
9938 useful to have more importers for other package formats, and your help
9939 is welcome here (@pxref{Contributing}).
9941 @node Invoking guix refresh
9942 @section Invoking @command{guix refresh}
9944 @cindex @command {guix refresh}
9945 The primary audience of the @command{guix refresh} command is developers
9946 of the GNU software distribution. By default, it reports any packages
9947 provided by the distribution that are outdated compared to the latest
9948 upstream version, like this:
9952 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
9953 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
9956 Alternatively, one can specify packages to consider, in which case a
9957 warning is emitted for packages that lack an updater:
9960 $ guix refresh coreutils guile guile-ssh
9961 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
9962 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
9965 @command{guix refresh} browses the upstream repository of each package and determines
9966 the highest version number of the releases therein. The command
9967 knows how to update specific types of packages: GNU packages, ELPA
9968 packages, etc.---see the documentation for @option{--type} below. There
9969 are many packages, though, for which it lacks a method to determine
9970 whether a new upstream release is available. However, the mechanism is
9971 extensible, so feel free to get in touch with us to add a new method!
9976 Consider the packages specified, and all the packages upon which they depend.
9979 $ guix refresh --recursive coreutils
9980 gnu/packages/acl.scm:35:2: warning: no updater for acl
9981 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
9982 gnu/packages/xml.scm:68:2: warning: no updater for expat
9983 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
9989 Sometimes the upstream name differs from the package name used in Guix,
9990 and @command{guix refresh} needs a little help. Most updaters honor the
9991 @code{upstream-name} property in package definitions, which can be used
9995 (define-public network-manager
9997 (name "network-manager")
9999 (properties '((upstream-name . "NetworkManager")))))
10002 When passed @option{--update}, it modifies distribution source files to
10003 update the version numbers and source tarball hashes of those package
10004 recipes (@pxref{Defining Packages}). This is achieved by downloading
10005 each package's latest source tarball and its associated OpenPGP
10006 signature, authenticating the downloaded tarball against its signature
10007 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
10008 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
10011 key used to sign the tarball is missing from the user's keyring, an
10012 attempt is made to automatically retrieve it from a public key server;
10013 when this is successful, the key is added to the user's keyring; otherwise,
10014 @command{guix refresh} reports an error.
10016 The following options are supported:
10020 @item --expression=@var{expr}
10021 @itemx -e @var{expr}
10022 Consider the package @var{expr} evaluates to.
10024 This is useful to precisely refer to a package, as in this example:
10027 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
10030 This command lists the dependents of the ``final'' libc (essentially all
10035 Update distribution source files (package recipes) in place. This is
10036 usually run from a checkout of the Guix source tree (@pxref{Running
10037 Guix Before It Is Installed}):
10040 $ ./pre-inst-env guix refresh -s non-core -u
10043 @xref{Defining Packages}, for more information on package definitions.
10045 @item --select=[@var{subset}]
10046 @itemx -s @var{subset}
10047 Select all the packages in @var{subset}, one of @code{core} or
10050 The @code{core} subset refers to all the packages at the core of the
10051 distribution---i.e., packages that are used to build ``everything
10052 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
10053 changing one of these packages in the distribution entails a rebuild of
10054 all the others. Thus, such updates are an inconvenience to users in
10055 terms of build time or bandwidth used to achieve the upgrade.
10057 The @code{non-core} subset refers to the remaining packages. It is
10058 typically useful in cases where an update of the core packages would be
10061 @item --manifest=@var{file}
10062 @itemx -m @var{file}
10063 Select all the packages from the manifest in @var{file}. This is useful to
10064 check if any packages of the user manifest can be updated.
10066 @item --type=@var{updater}
10067 @itemx -t @var{updater}
10068 Select only packages handled by @var{updater} (may be a comma-separated
10069 list of updaters). Currently, @var{updater} may be one of:
10073 the updater for GNU packages;
10075 the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
10077 the updater for GNOME packages;
10079 the updater for KDE packages;
10081 the updater for X.org packages;
10083 the updater for packages hosted on kernel.org;
10085 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
10087 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
10089 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
10091 the updater for @uref{https://www.cpan.org/, CPAN} packages;
10093 the updater for @uref{https://pypi.python.org, PyPI} packages.
10095 the updater for @uref{https://rubygems.org, RubyGems} packages.
10097 the updater for @uref{https://github.com, GitHub} packages.
10099 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
10101 the updater for @uref{https://www.stackage.org, Stackage} packages.
10103 the updater for @uref{https://crates.io, Crates} packages.
10105 the updater for @uref{https://launchpad.net, Launchpad} packages.
10108 For instance, the following command only checks for updates of Emacs
10109 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
10112 $ guix refresh --type=elpa,cran
10113 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
10114 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
10119 In addition, @command{guix refresh} can be passed one or more package
10120 names, as in this example:
10123 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
10127 The command above specifically updates the @code{emacs} and
10128 @code{idutils} packages. The @option{--select} option would have no
10129 effect in this case.
10131 When considering whether to upgrade a package, it is sometimes
10132 convenient to know which packages would be affected by the upgrade and
10133 should be checked for compatibility. For this the following option may
10134 be used when passing @command{guix refresh} one or more package names:
10138 @item --list-updaters
10140 List available updaters and exit (see @option{--type} above).
10142 For each updater, display the fraction of packages it covers; at the
10143 end, display the fraction of packages covered by all these updaters.
10145 @item --list-dependent
10147 List top-level dependent packages that would need to be rebuilt as a
10148 result of upgrading one or more packages.
10150 @xref{Invoking guix graph, the @code{reverse-package} type of
10151 @command{guix graph}}, for information on how to visualize the list of
10152 dependents of a package.
10156 Be aware that the @option{--list-dependent} option only
10157 @emph{approximates} the rebuilds that would be required as a result of
10158 an upgrade. More rebuilds might be required under some circumstances.
10161 $ guix refresh --list-dependent flex
10162 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
10163 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
10166 The command above lists a set of packages that could be built to check
10167 for compatibility with an upgraded @code{flex} package.
10171 @item --list-transitive
10172 List all the packages which one or more packages depend upon.
10175 $ guix refresh --list-transitive flex
10176 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
10177 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{}
10182 The command above lists a set of packages which, when changed, would cause
10183 @code{flex} to be rebuilt.
10185 The following options can be used to customize GnuPG operation:
10189 @item --gpg=@var{command}
10190 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
10191 for in @code{$PATH}.
10193 @item --keyring=@var{file}
10194 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
10195 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
10196 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
10197 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
10198 information on a tool to manipulate keybox files).
10200 When this option is omitted, @command{guix refresh} uses
10201 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
10202 signing keys. OpenPGP signatures are checked against keys from this keyring;
10203 missing keys are downloaded to this keyring as well (see
10204 @option{--key-download} below).
10206 You can export keys from your default GPG keyring into a keybox file using
10207 commands like this one:
10210 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
10213 Likewise, you can fetch keys to a specific keybox file like this:
10216 gpg --no-default-keyring --keyring mykeyring.kbx \
10217 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
10220 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
10221 Privacy Guard}, for more information on GPG's @option{--keyring} option.
10223 @item --key-download=@var{policy}
10224 Handle missing OpenPGP keys according to @var{policy}, which may be one
10229 Always download missing OpenPGP keys from the key server, and add them
10230 to the user's GnuPG keyring.
10233 Never try to download missing OpenPGP keys. Instead just bail out.
10236 When a package signed with an unknown OpenPGP key is encountered, ask
10237 the user whether to download it or not. This is the default behavior.
10240 @item --key-server=@var{host}
10241 Use @var{host} as the OpenPGP key server when importing a public key.
10243 @item --load-path=@var{directory}
10244 Add @var{directory} to the front of the package module search path
10245 (@pxref{Package Modules}).
10247 This allows users to define their own packages and make them visible to
10248 the command-line tools.
10252 The @code{github} updater uses the
10253 @uref{https://developer.github.com/v3/, GitHub API} to query for new
10254 releases. When used repeatedly e.g.@: when refreshing all packages,
10255 GitHub will eventually refuse to answer any further API requests. By
10256 default 60 API requests per hour are allowed, and a full refresh on all
10257 GitHub packages in Guix requires more than this. Authentication with
10258 GitHub through the use of an API token alleviates these limits. To use
10259 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
10260 token procured from @uref{https://github.com/settings/tokens} or
10264 @node Invoking guix lint
10265 @section Invoking @command{guix lint}
10267 @cindex @command{guix lint}
10268 @cindex package, checking for errors
10269 The @command{guix lint} command is meant to help package developers avoid
10270 common errors and use a consistent style. It runs a number of checks on
10271 a given set of packages in order to find common mistakes in their
10272 definitions. Available @dfn{checkers} include (see
10273 @option{--list-checkers} for a complete list):
10278 Validate certain typographical and stylistic rules about package
10279 descriptions and synopses.
10281 @item inputs-should-be-native
10282 Identify inputs that should most likely be native inputs.
10288 @itemx source-file-name
10289 Probe @code{home-page} and @code{source} URLs and report those that are
10290 invalid. Suggest a @code{mirror://} URL when applicable. If the
10291 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
10292 URL. Check that the source file name is meaningful, e.g.@: is not just a
10293 version number or ``git-checkout'', without a declared @code{file-name}
10294 (@pxref{origin Reference}).
10296 @item source-unstable-tarball
10297 Parse the @code{source} URL to determine if a tarball from GitHub is
10298 autogenerated or if it is a release tarball. Unfortunately GitHub's
10299 autogenerated tarballs are sometimes regenerated.
10302 Check that the derivation of the given packages can be successfully
10303 computed for all the supported systems (@pxref{Derivations}).
10305 @item profile-collisions
10306 Check whether installing the given packages in a profile would lead to
10307 collisions. Collisions occur when several packages with the same name
10308 but a different version or a different store file name are propagated.
10309 @xref{package Reference, @code{propagated-inputs}}, for more information
10310 on propagated inputs.
10313 @cindex Software Heritage, source code archive
10314 @cindex archival of source code, Software Heritage
10315 Checks whether the package's source code is archived at
10316 @uref{https://www.softwareheritage.org, Software Heritage}.
10318 When the source code that is not archived comes from a version-control system
10319 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
10320 ``save'' request so that it eventually archives it. This ensures that the
10321 source will remain available in the long term, and that Guix can fall back to
10322 Software Heritage should the source code disappear from its original host.
10323 The status of recent ``save'' requests can be
10324 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
10326 When source code is a tarball obtained with @code{url-fetch}, simply print a
10327 message when it is not archived. As of this writing, Software Heritage does
10328 not allow requests to save arbitrary tarballs; we are working on ways to
10329 ensure that non-VCS source code is also archived.
10332 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
10333 request rate per IP address}. When the limit is reached, @command{guix lint}
10334 prints a message and the @code{archival} checker stops doing anything until
10335 that limit has been reset.
10338 @cindex security vulnerabilities
10339 @cindex CVE, Common Vulnerabilities and Exposures
10340 Report known vulnerabilities found in the Common Vulnerabilities and
10341 Exposures (CVE) databases of the current and past year
10342 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
10345 To view information about a particular vulnerability, visit pages such as:
10349 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
10351 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
10355 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
10356 @code{CVE-2015-7554}.
10358 Package developers can specify in package recipes the
10359 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
10360 name and version of the package when they differ from the name or version
10361 that Guix uses, as in this example:
10367 ;; CPE calls this package "grub2".
10368 (properties '((cpe-name . "grub2")
10369 (cpe-version . "2.3"))))
10372 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
10373 Some entries in the CVE database do not specify which version of a
10374 package they apply to, and would thus ``stick around'' forever. Package
10375 developers who found CVE alerts and verified they can be ignored can
10376 declare them as in this example:
10382 ;; These CVEs no longer apply and can be safely ignored.
10383 (properties `((lint-hidden-cve . ("CVE-2011-0433"
10386 "CVE-2011-5244")))))
10390 Warn about obvious source code formatting issues: trailing white space,
10391 use of tabulations, etc.
10394 The general syntax is:
10397 guix lint @var{options} @var{package}@dots{}
10400 If no package is given on the command line, then all packages are checked.
10401 The @var{options} may be zero or more of the following:
10404 @item --list-checkers
10406 List and describe all the available checkers that will be run on packages
10411 Only enable the checkers specified in a comma-separated list using the
10412 names returned by @option{--list-checkers}.
10414 @item --load-path=@var{directory}
10415 @itemx -L @var{directory}
10416 Add @var{directory} to the front of the package module search path
10417 (@pxref{Package Modules}).
10419 This allows users to define their own packages and make them visible to
10420 the command-line tools.
10424 @node Invoking guix size
10425 @section Invoking @command{guix size}
10428 @cindex package size
10430 @cindex @command{guix size}
10431 The @command{guix size} command helps package developers profile the
10432 disk usage of packages. It is easy to overlook the impact of an
10433 additional dependency added to a package, or the impact of using a
10434 single output for a package that could easily be split (@pxref{Packages
10435 with Multiple Outputs}). Such are the typical issues that
10436 @command{guix size} can highlight.
10438 The command can be passed one or more package specifications
10439 such as @code{gcc@@4.8}
10440 or @code{guile:debug}, or a file name in the store. Consider this
10444 $ guix size coreutils
10445 store item total self
10446 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
10447 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
10448 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
10449 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
10450 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
10451 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
10452 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
10453 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
10458 The store items listed here constitute the @dfn{transitive closure} of
10459 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
10460 would be returned by:
10463 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
10466 Here the output shows three columns next to store items. The first column,
10467 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
10468 the store item---that is, its own size plus the size of all its
10469 dependencies. The next column, labeled ``self'', shows the size of the
10470 item itself. The last column shows the ratio of the size of the item
10471 itself to the space occupied by all the items listed here.
10473 In this example, we see that the closure of Coreutils weighs in at
10474 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
10475 libraries. (That libc and GCC's libraries represent a large fraction of
10476 the closure is not a problem @i{per se} because they are always available
10477 on the system anyway.)
10479 Since the command also accepts store file names, assessing the size of
10480 a build result is straightforward:
10483 guix size $(guix system build config.scm)
10486 When the package(s) passed to @command{guix size} are available in the
10487 store@footnote{More precisely, @command{guix size} looks for the
10488 @emph{ungrafted} variant of the given package(s), as returned by
10489 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
10490 for information on grafts.}, @command{guix size} queries the daemon to determine its
10491 dependencies, and measures its size in the store, similar to @command{du
10492 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
10495 When the given packages are @emph{not} in the store, @command{guix size}
10496 reports information based on the available substitutes
10497 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
10498 store items that are not even on disk, only available remotely.
10500 You can also specify several package names:
10503 $ guix size coreutils grep sed bash
10504 store item total self
10505 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
10506 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
10507 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
10508 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
10514 In this example we see that the combination of the four packages takes
10515 102.3@tie{}MiB in total, which is much less than the sum of each closure
10516 since they have a lot of dependencies in common.
10518 When looking at the profile returned by @command{guix size}, you may
10519 find yourself wondering why a given package shows up in the profile at
10520 all. To understand it, you can use @command{guix graph --path -t
10521 references} to display the shortest path between the two packages
10522 (@pxref{Invoking guix graph}).
10524 The available options are:
10528 @item --substitute-urls=@var{urls}
10529 Use substitute information from @var{urls}.
10530 @xref{client-substitute-urls, the same option for @code{guix build}}.
10532 @item --sort=@var{key}
10533 Sort lines according to @var{key}, one of the following options:
10537 the size of each item (the default);
10539 the total size of the item's closure.
10542 @item --map-file=@var{file}
10543 Write a graphical map of disk usage in PNG format to @var{file}.
10545 For the example above, the map looks like this:
10547 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
10548 produced by @command{guix size}}
10550 This option requires that
10551 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
10552 installed and visible in Guile's module search path. When that is not
10553 the case, @command{guix size} fails as it tries to load it.
10555 @item --system=@var{system}
10556 @itemx -s @var{system}
10557 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
10559 @item --load-path=@var{directory}
10560 @itemx -L @var{directory}
10561 Add @var{directory} to the front of the package module search path
10562 (@pxref{Package Modules}).
10564 This allows users to define their own packages and make them visible to
10565 the command-line tools.
10568 @node Invoking guix graph
10569 @section Invoking @command{guix graph}
10572 @cindex @command{guix graph}
10573 @cindex package dependencies
10574 Packages and their dependencies form a @dfn{graph}, specifically a
10575 directed acyclic graph (DAG). It can quickly become difficult to have a
10576 mental model of the package DAG, so the @command{guix graph} command
10577 provides a visual representation of the DAG. By default,
10578 @command{guix graph} emits a DAG representation in the input format of
10579 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
10580 directly to the @command{dot} command of Graphviz. It can also emit an
10581 HTML page with embedded JavaScript code to display a ``chord diagram''
10582 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
10583 emit Cypher queries to construct a graph in a graph database supporting
10584 the @uref{https://www.opencypher.org/, openCypher} query language. With
10585 @option{--path}, it simply displays the shortest path between two
10586 packages. The general syntax is:
10589 guix graph @var{options} @var{package}@dots{}
10592 For example, the following command generates a PDF file representing the
10593 package DAG for the GNU@tie{}Core Utilities, showing its build-time
10597 guix graph coreutils | dot -Tpdf > dag.pdf
10600 The output looks like this:
10602 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
10604 Nice little graph, no?
10606 You may find it more pleasant to navigate the graph interactively with
10607 @command{xdot} (from the @code{xdot} package):
10610 guix graph coreutils | xdot -
10613 But there is more than one graph! The one above is concise: it is the
10614 graph of package objects, omitting implicit inputs such as GCC, libc,
10615 grep, etc. It is often useful to have such a concise graph, but
10616 sometimes one may want to see more details. @command{guix graph} supports
10617 several types of graphs, allowing you to choose the level of detail:
10621 This is the default type used in the example above. It shows the DAG of
10622 package objects, excluding implicit dependencies. It is concise, but
10623 filters out many details.
10625 @item reverse-package
10626 This shows the @emph{reverse} DAG of packages. For example:
10629 guix graph --type=reverse-package ocaml
10632 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
10633 you are also interested in cases where OCaml is an implicit dependency, see
10634 @code{reverse-bag} below).
10636 Note that for core packages this can yield huge graphs. If all you want
10637 is to know the number of packages that depend on a given package, use
10638 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
10639 @option{--list-dependent}}).
10642 This is the package DAG, @emph{including} implicit inputs.
10644 For instance, the following command:
10647 guix graph --type=bag-emerged coreutils
10650 ...@: yields this bigger graph:
10652 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
10654 At the bottom of the graph, we see all the implicit inputs of
10655 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
10657 Now, note that the dependencies of these implicit inputs---that is, the
10658 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
10659 here, for conciseness.
10662 Similar to @code{bag-emerged}, but this time including all the bootstrap
10665 @item bag-with-origins
10666 Similar to @code{bag}, but also showing origins and their dependencies.
10669 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
10670 it also takes implicit dependencies into account. For example:
10673 guix graph -t reverse-bag dune
10677 ...@: yields the graph of all packages that depend on Dune, directly or
10678 indirectly. Since Dune is an @emph{implicit} dependency of many packages
10679 @i{via} @code{dune-build-system}, this shows a large number of packages,
10680 whereas @code{reverse-package} would show very few if any.
10683 This is the most detailed representation: It shows the DAG of
10684 derivations (@pxref{Derivations}) and plain store items. Compared to
10685 the above representation, many additional nodes are visible, including
10686 build scripts, patches, Guile modules, etc.
10688 For this type of graph, it is also possible to pass a @file{.drv} file
10689 name instead of a package name, as in:
10692 guix graph -t derivation `guix system build -d my-config.scm`
10696 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
10697 For example, the following command shows the graph for the package
10698 module that defines the @code{guile} package:
10701 guix graph -t module guile | xdot -
10705 All the types above correspond to @emph{build-time dependencies}. The
10706 following graph type represents the @emph{run-time dependencies}:
10710 This is the graph of @dfn{references} of a package output, as returned
10711 by @command{guix gc --references} (@pxref{Invoking guix gc}).
10713 If the given package output is not available in the store, @command{guix
10714 graph} attempts to obtain dependency information from substitutes.
10716 Here you can also pass a store file name instead of a package name. For
10717 example, the command below produces the reference graph of your profile
10718 (which can be big!):
10721 guix graph -t references `readlink -f ~/.guix-profile`
10725 This is the graph of the @dfn{referrers} of a store item, as returned by
10726 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
10728 This relies exclusively on local information from your store. For
10729 instance, let us suppose that the current Inkscape is available in 10
10730 profiles on your machine; @command{guix graph -t referrers inkscape}
10731 will show a graph rooted at Inkscape and with those 10 profiles linked
10734 It can help determine what is preventing a store item from being garbage
10739 @cindex shortest path, between packages
10740 Often, the graph of the package you are interested in does not fit on
10741 your screen, and anyway all you want to know is @emph{why} that package
10742 actually depends on some seemingly unrelated package. The
10743 @option{--path} option instructs @command{guix graph} to display the
10744 shortest path between two packages (or derivations, or store items,
10748 $ guix graph --path emacs libunistring
10751 libunistring@@0.9.10
10752 $ guix graph --path -t derivation emacs libunistring
10753 /gnu/store/@dots{}-emacs-26.3.drv
10754 /gnu/store/@dots{}-mailutils-3.9.drv
10755 /gnu/store/@dots{}-libunistring-0.9.10.drv
10756 $ guix graph --path -t references emacs libunistring
10757 /gnu/store/@dots{}-emacs-26.3
10758 /gnu/store/@dots{}-libidn2-2.2.0
10759 /gnu/store/@dots{}-libunistring-0.9.10
10762 The available options are the following:
10765 @item --type=@var{type}
10766 @itemx -t @var{type}
10767 Produce a graph output of @var{type}, where @var{type} must be one of
10768 the values listed above.
10771 List the supported graph types.
10773 @item --backend=@var{backend}
10774 @itemx -b @var{backend}
10775 Produce a graph using the selected @var{backend}.
10777 @item --list-backends
10778 List the supported graph backends.
10780 Currently, the available backends are Graphviz and d3.js.
10783 Display the shortest path between two nodes of the type specified by
10784 @option{--type}. The example below shows the shortest path between
10785 @code{libreoffice} and @code{llvm} according to the references of
10786 @code{libreoffice}:
10789 $ guix graph --path -t references libreoffice llvm
10790 /gnu/store/@dots{}-libreoffice-6.4.2.2
10791 /gnu/store/@dots{}-libepoxy-1.5.4
10792 /gnu/store/@dots{}-mesa-19.3.4
10793 /gnu/store/@dots{}-llvm-9.0.1
10796 @item --expression=@var{expr}
10797 @itemx -e @var{expr}
10798 Consider the package @var{expr} evaluates to.
10800 This is useful to precisely refer to a package, as in this example:
10803 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
10806 @item --system=@var{system}
10807 @itemx -s @var{system}
10808 Display the graph for @var{system}---e.g., @code{i686-linux}.
10810 The package dependency graph is largely architecture-independent, but there
10811 are some architecture-dependent bits that this option allows you to visualize.
10813 @item --load-path=@var{directory}
10814 @itemx -L @var{directory}
10815 Add @var{directory} to the front of the package module search path
10816 (@pxref{Package Modules}).
10818 This allows users to define their own packages and make them visible to
10819 the command-line tools.
10822 On top of that, @command{guix graph} supports all the usual package
10823 transformation options (@pxref{Package Transformation Options}). This
10824 makes it easy to view the effect of a graph-rewriting transformation
10825 such as @option{--with-input}. For example, the command below outputs
10826 the graph of @code{git} once @code{openssl} has been replaced by
10827 @code{libressl} everywhere in the graph:
10830 guix graph git --with-input=openssl=libressl
10833 So many possibilities, so much fun!
10835 @node Invoking guix publish
10836 @section Invoking @command{guix publish}
10838 @cindex @command{guix publish}
10839 The purpose of @command{guix publish} is to enable users to easily share
10840 their store with others, who can then use it as a substitute server
10841 (@pxref{Substitutes}).
10843 When @command{guix publish} runs, it spawns an HTTP server which allows
10844 anyone with network access to obtain substitutes from it. This means
10845 that any machine running Guix can also act as if it were a build farm,
10846 since the HTTP interface is compatible with Cuirass, the software behind
10847 the @code{@value{SUBSTITUTE-SERVER}} build farm.
10849 For security, each substitute is signed, allowing recipients to check
10850 their authenticity and integrity (@pxref{Substitutes}). Because
10851 @command{guix publish} uses the signing key of the system, which is only
10852 readable by the system administrator, it must be started as root; the
10853 @option{--user} option makes it drop root privileges early on.
10855 The signing key pair must be generated before @command{guix publish} is
10856 launched, using @command{guix archive --generate-key} (@pxref{Invoking
10859 The general syntax is:
10862 guix publish @var{options}@dots{}
10865 Running @command{guix publish} without any additional arguments will
10866 spawn an HTTP server on port 8080:
10872 Once a publishing server has been authorized (@pxref{Invoking guix
10873 archive}), the daemon may download substitutes from it:
10876 guix-daemon --substitute-urls=http://example.org:8080
10879 By default, @command{guix publish} compresses archives on the fly as it
10880 serves them. This ``on-the-fly'' mode is convenient in that it requires
10881 no setup and is immediately available. However, when serving lots of
10882 clients, we recommend using the @option{--cache} option, which enables
10883 caching of the archives before they are sent to clients---see below for
10884 details. The @command{guix weather} command provides a handy way to
10885 check what a server provides (@pxref{Invoking guix weather}).
10887 As a bonus, @command{guix publish} also serves as a content-addressed
10888 mirror for source files referenced in @code{origin} records
10889 (@pxref{origin Reference}). For instance, assuming @command{guix
10890 publish} is running on @code{example.org}, the following URL returns the
10891 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
10892 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
10895 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
10898 Obviously, these URLs only work for files that are in the store; in
10899 other cases, they return 404 (``Not Found'').
10901 @cindex build logs, publication
10902 Build logs are available from @code{/log} URLs like:
10905 http://example.org/log/gwspk@dots{}-guile-2.2.3
10909 When @command{guix-daemon} is configured to save compressed build logs,
10910 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
10911 URLs return the compressed log as-is, with an appropriate
10912 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
10913 running @command{guix-daemon} with @option{--log-compression=gzip} since
10914 Web browsers can automatically decompress it, which is not the case with
10917 The following options are available:
10920 @item --port=@var{port}
10921 @itemx -p @var{port}
10922 Listen for HTTP requests on @var{port}.
10924 @item --listen=@var{host}
10925 Listen on the network interface for @var{host}. The default is to
10926 accept connections from any interface.
10928 @item --user=@var{user}
10929 @itemx -u @var{user}
10930 Change privileges to @var{user} as soon as possible---i.e., once the
10931 server socket is open and the signing key has been read.
10933 @item --compression[=@var{method}[:@var{level}]]
10934 @itemx -C [@var{method}[:@var{level}]]
10935 Compress data using the given @var{method} and @var{level}. @var{method} is
10936 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
10939 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
10940 to different compression levels: 1 is the fastest, and 9 is the best
10941 (CPU-intensive). The default is 3.
10943 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
10944 increase in CPU usage; see
10945 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
10948 Unless @option{--cache} is used, compression occurs on the fly and
10949 the compressed streams are not
10950 cached. Thus, to reduce load on the machine that runs @command{guix
10951 publish}, it may be a good idea to choose a low compression level, to
10952 run @command{guix publish} behind a caching proxy, or to use
10953 @option{--cache}. Using @option{--cache} has the advantage that it
10954 allows @command{guix publish} to add @code{Content-Length} HTTP header
10957 This option can be repeated, in which case every substitute gets compressed
10958 using all the selected methods, and all of them are advertised. This is
10959 useful when users may not support all the compression methods: they can select
10960 the one they support.
10962 @item --cache=@var{directory}
10963 @itemx -c @var{directory}
10964 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
10965 and only serve archives that are in cache.
10967 When this option is omitted, archives and meta-data are created
10968 on-the-fly. This can reduce the available bandwidth, especially when
10969 compression is enabled, since this may become CPU-bound. Another
10970 drawback of the default mode is that the length of archives is not known
10971 in advance, so @command{guix publish} does not add a
10972 @code{Content-Length} HTTP header to its responses, which in turn
10973 prevents clients from knowing the amount of data being downloaded.
10975 Conversely, when @option{--cache} is used, the first request for a store
10976 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
10977 background process to @dfn{bake} the archive---computing its
10978 @code{.narinfo} and compressing the archive, if needed. Once the
10979 archive is cached in @var{directory}, subsequent requests succeed and
10980 are served directly from the cache, which guarantees that clients get
10981 the best possible bandwidth.
10983 The ``baking'' process is performed by worker threads. By default, one
10984 thread per CPU core is created, but this can be customized. See
10985 @option{--workers} below.
10987 When @option{--ttl} is used, cached entries are automatically deleted
10988 when they have expired.
10990 @item --workers=@var{N}
10991 When @option{--cache} is used, request the allocation of @var{N} worker
10992 threads to ``bake'' archives.
10994 @item --ttl=@var{ttl}
10995 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
10996 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
10997 days, @code{1m} means 1 month, and so on.
10999 This allows the user's Guix to keep substitute information in cache for
11000 @var{ttl}. However, note that @code{guix publish} does not itself
11001 guarantee that the store items it provides will indeed remain available
11002 for as long as @var{ttl}.
11004 Additionally, when @option{--cache} is used, cached entries that have
11005 not been accessed for @var{ttl} and that no longer have a corresponding
11006 item in the store, may be deleted.
11008 @item --nar-path=@var{path}
11009 Use @var{path} as the prefix for the URLs of ``nar'' files
11010 (@pxref{Invoking guix archive, normalized archives}).
11012 By default, nars are served at a URL such as
11013 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
11014 change the @code{/nar} part to @var{path}.
11016 @item --public-key=@var{file}
11017 @itemx --private-key=@var{file}
11018 Use the specific @var{file}s as the public/private key pair used to sign
11019 the store items being published.
11021 The files must correspond to the same key pair (the private key is used
11022 for signing and the public key is merely advertised in the signature
11023 metadata). They must contain keys in the canonical s-expression format
11024 as produced by @command{guix archive --generate-key} (@pxref{Invoking
11025 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
11026 @file{/etc/guix/signing-key.sec} are used.
11028 @item --repl[=@var{port}]
11029 @itemx -r [@var{port}]
11030 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
11031 Reference Manual}) on @var{port} (37146 by default). This is used
11032 primarily for debugging a running @command{guix publish} server.
11035 Enabling @command{guix publish} on Guix System is a one-liner: just
11036 instantiate a @code{guix-publish-service-type} service in the @code{services} field
11037 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
11038 @code{guix-publish-service-type}}).
11040 If you are instead running Guix on a ``foreign distro'', follow these
11045 If your host distro uses the systemd init system:
11048 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
11049 /etc/systemd/system/
11050 # systemctl start guix-publish && systemctl enable guix-publish
11054 If your host distro uses the Upstart init system:
11057 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
11058 # start guix-publish
11062 Otherwise, proceed similarly with your distro's init system.
11065 @node Invoking guix challenge
11066 @section Invoking @command{guix challenge}
11068 @cindex reproducible builds
11069 @cindex verifiable builds
11070 @cindex @command{guix challenge}
11072 Do the binaries provided by this server really correspond to the source
11073 code it claims to build? Is a package build process deterministic?
11074 These are the questions the @command{guix challenge} command attempts to
11077 The former is obviously an important question: Before using a substitute
11078 server (@pxref{Substitutes}), one had better @emph{verify} that it
11079 provides the right binaries, and thus @emph{challenge} it. The latter
11080 is what enables the former: If package builds are deterministic, then
11081 independent builds of the package should yield the exact same result,
11082 bit for bit; if a server provides a binary different from the one
11083 obtained locally, it may be either corrupt or malicious.
11085 We know that the hash that shows up in @file{/gnu/store} file names is
11086 the hash of all the inputs of the process that built the file or
11087 directory---compilers, libraries, build scripts,
11088 etc. (@pxref{Introduction}). Assuming deterministic build processes,
11089 one store file name should map to exactly one build output.
11090 @command{guix challenge} checks whether there is, indeed, a single
11091 mapping by comparing the build outputs of several independent builds of
11092 any given store item.
11094 The command output looks like this:
11097 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
11098 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
11099 updating list of substitutes from 'https://guix.example.org'... 100.0%
11100 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
11101 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
11102 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
11103 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
11105 /lib/libcrypto.so.1.1
11108 /gnu/store/@dots{}-git-2.5.0 contents differ:
11109 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
11110 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
11111 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
11113 /libexec/git-core/git-fsck
11115 /gnu/store/@dots{}-pius-2.1.1 contents differ:
11116 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
11117 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
11118 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
11120 /share/man/man1/pius.1.gz
11124 6,406 store items were analyzed:
11125 - 4,749 (74.1%) were identical
11126 - 525 (8.2%) differed
11127 - 1,132 (17.7%) were inconclusive
11131 In this example, @command{guix challenge} first scans the store to
11132 determine the set of locally-built derivations---as opposed to store
11133 items that were downloaded from a substitute server---and then queries
11134 all the substitute servers. It then reports those store items for which
11135 the servers obtained a result different from the local build.
11137 @cindex non-determinism, in package builds
11138 As an example, @code{guix.example.org} always gets a different answer.
11139 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
11140 case of Git. This might indicate that the build process of Git is
11141 non-deterministic, meaning that its output varies as a function of
11142 various things that Guix does not fully control, in spite of building
11143 packages in isolated environments (@pxref{Features}). Most common
11144 sources of non-determinism include the addition of timestamps in build
11145 results, the inclusion of random numbers, and directory listings sorted
11146 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
11149 To find out what is wrong with this Git binary, the easiest approach is
11153 guix challenge git \
11154 --diff=diffoscope \
11155 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
11158 This automatically invokes @command{diffoscope}, which displays detailed
11159 information about files that differ.
11161 Alternatively, we can do something along these lines (@pxref{Invoking guix
11165 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-git-2.5.0 \
11166 | lzip -d | guix archive -x /tmp/git
11167 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
11170 This command shows the difference between the files resulting from the
11171 local build, and the files resulting from the build on
11172 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
11173 diffutils, Comparing and Merging Files}). The @command{diff} command
11174 works great for text files. When binary files differ, a better option
11175 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
11176 visualize differences for all kinds of files.
11178 Once you have done that work, you can tell whether the differences are due
11179 to a non-deterministic build process or to a malicious server. We try
11180 hard to remove sources of non-determinism in packages to make it easier
11181 to verify substitutes, but of course, this is a process that
11182 involves not just Guix, but a large part of the free software community.
11183 In the meantime, @command{guix challenge} is one tool to help address
11186 If you are writing packages for Guix, you are encouraged to check
11187 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
11188 same build result as you did with:
11191 $ guix challenge @var{package}
11195 where @var{package} is a package specification such as
11196 @code{guile@@2.0} or @code{glibc:debug}.
11198 The general syntax is:
11201 guix challenge @var{options} [@var{packages}@dots{}]
11204 When a difference is found between the hash of a locally-built item and
11205 that of a server-provided substitute, or among substitutes provided by
11206 different servers, the command displays it as in the example above and
11207 its exit code is 2 (other non-zero exit codes denote other kinds of
11210 The one option that matters is:
11214 @item --substitute-urls=@var{urls}
11215 Consider @var{urls} the whitespace-separated list of substitute source
11216 URLs to compare to.
11218 @item --diff=@var{mode}
11219 Upon mismatches, show differences according to @var{mode}, one of:
11222 @item @code{simple} (the default)
11223 Show the list of files that differ.
11225 @item @code{diffoscope}
11226 @itemx @var{command}
11227 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
11228 two directories whose contents do not match.
11230 When @var{command} is an absolute file name, run @var{command} instead
11234 Do not show further details about the differences.
11237 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
11238 downloads the store items from the given substitute servers so that it
11243 Show details about matches (identical contents) in addition to
11244 information about mismatches.
11248 @node Invoking guix copy
11249 @section Invoking @command{guix copy}
11251 @cindex copy, of store items, over SSH
11252 @cindex SSH, copy of store items
11253 @cindex sharing store items across machines
11254 @cindex transferring store items across machines
11255 The @command{guix copy} command copies items from the store of one
11256 machine to that of another machine over a secure shell (SSH)
11257 connection@footnote{This command is available only when Guile-SSH was
11258 found. @xref{Requirements}, for details.}. For example, the following
11259 command copies the @code{coreutils} package, the user's profile, and all
11260 their dependencies over to @var{host}, logged in as @var{user}:
11263 guix copy --to=@var{user}@@@var{host} \
11264 coreutils `readlink -f ~/.guix-profile`
11267 If some of the items to be copied are already present on @var{host},
11268 they are not actually sent.
11270 The command below retrieves @code{libreoffice} and @code{gimp} from
11271 @var{host}, assuming they are available there:
11274 guix copy --from=@var{host} libreoffice gimp
11277 The SSH connection is established using the Guile-SSH client, which is
11278 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
11279 @file{~/.ssh/config}, and uses the SSH agent for authentication.
11281 The key used to sign items that are sent must be accepted by the remote
11282 machine. Likewise, the key used by the remote machine to sign items you
11283 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
11284 own daemon. @xref{Invoking guix archive}, for more information about
11285 store item authentication.
11287 The general syntax is:
11290 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
11293 You must always specify one of the following options:
11296 @item --to=@var{spec}
11297 @itemx --from=@var{spec}
11298 Specify the host to send to or receive from. @var{spec} must be an SSH
11299 spec such as @code{example.org}, @code{charlie@@example.org}, or
11300 @code{charlie@@example.org:2222}.
11303 The @var{items} can be either package names, such as @code{gimp}, or
11304 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
11306 When specifying the name of a package to send, it is first built if
11307 needed, unless @option{--dry-run} was specified. Common build options
11308 are supported (@pxref{Common Build Options}).
11311 @node Invoking guix container
11312 @section Invoking @command{guix container}
11314 @cindex @command{guix container}
11316 As of version @value{VERSION}, this tool is experimental. The interface
11317 is subject to radical change in the future.
11320 The purpose of @command{guix container} is to manipulate processes
11321 running within an isolated environment, commonly known as a
11322 ``container'', typically created by the @command{guix environment}
11323 (@pxref{Invoking guix environment}) and @command{guix system container}
11324 (@pxref{Invoking guix system}) commands.
11326 The general syntax is:
11329 guix container @var{action} @var{options}@dots{}
11332 @var{action} specifies the operation to perform with a container, and
11333 @var{options} specifies the context-specific arguments for the action.
11335 The following actions are available:
11339 Execute a command within the context of a running container.
11344 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
11347 @var{pid} specifies the process ID of the running container.
11348 @var{program} specifies an executable file name within the root file
11349 system of the container. @var{arguments} are the additional options that
11350 will be passed to @var{program}.
11352 The following command launches an interactive login shell inside a
11353 Guix system container, started by @command{guix system container}, and whose
11354 process ID is 9001:
11357 guix container exec 9001 /run/current-system/profile/bin/bash --login
11360 Note that the @var{pid} cannot be the parent process of a container. It
11361 must be PID 1 of the container or one of its child processes.
11365 @node Invoking guix weather
11366 @section Invoking @command{guix weather}
11368 Occasionally you're grumpy because substitutes are lacking and you end
11369 up building packages by yourself (@pxref{Substitutes}). The
11370 @command{guix weather} command reports on substitute availability on the
11371 specified servers so you can have an idea of whether you'll be grumpy
11372 today. It can sometimes be useful info as a user, but it is primarily
11373 useful to people running @command{guix publish} (@pxref{Invoking guix
11376 @cindex statistics, for substitutes
11377 @cindex availability of substitutes
11378 @cindex substitute availability
11379 @cindex weather, substitute availability
11380 Here's a sample run:
11383 $ guix weather --substitute-urls=https://guix.example.org
11384 computing 5,872 package derivations for x86_64-linux...
11385 looking for 6,128 store items on https://guix.example.org..
11386 updating list of substitutes from 'https://guix.example.org'... 100.0%
11387 https://guix.example.org
11388 43.4% substitutes available (2,658 out of 6,128)
11389 7,032.5 MiB of nars (compressed)
11390 19,824.2 MiB on disk (uncompressed)
11391 0.030 seconds per request (182.9 seconds in total)
11392 33.5 requests per second
11394 9.8% (342 out of 3,470) of the missing items are queued
11396 x86_64-linux: 518 (59.7%)
11397 i686-linux: 221 (25.5%)
11398 aarch64-linux: 128 (14.8%)
11399 build rate: 23.41 builds per hour
11400 x86_64-linux: 11.16 builds per hour
11401 i686-linux: 6.03 builds per hour
11402 aarch64-linux: 6.41 builds per hour
11405 @cindex continuous integration, statistics
11406 As you can see, it reports the fraction of all the packages for which
11407 substitutes are available on the server---regardless of whether
11408 substitutes are enabled, and regardless of whether this server's signing
11409 key is authorized. It also reports the size of the compressed archives
11410 (``nars'') provided by the server, the size the corresponding store
11411 items occupy in the store (assuming deduplication is turned off), and
11412 the server's throughput. The second part gives continuous integration
11413 (CI) statistics, if the server supports it. In addition, using the
11414 @option{--coverage} option, @command{guix weather} can list ``important''
11415 package substitutes missing on the server (see below).
11417 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
11418 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
11419 challenge}, it ignores signatures on those substitutes, which is
11420 innocuous since the command only gathers statistics and cannot install
11423 The general syntax is:
11426 guix weather @var{options}@dots{} [@var{packages}@dots{}]
11429 When @var{packages} is omitted, @command{guix weather} checks the availability
11430 of substitutes for @emph{all} the packages, or for those specified with
11431 @option{--manifest}; otherwise it only considers the specified packages. It
11432 is also possible to query specific system types with @option{--system}.
11433 @command{guix weather} exits with a non-zero code when the fraction of
11434 available substitutes is below 100%.
11436 The available options are listed below.
11439 @item --substitute-urls=@var{urls}
11440 @var{urls} is the space-separated list of substitute server URLs to
11441 query. When this option is omitted, the default set of substitute
11442 servers is queried.
11444 @item --system=@var{system}
11445 @itemx -s @var{system}
11446 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
11447 option can be repeated, in which case @command{guix weather} will query
11448 substitutes for several system types.
11450 @item --manifest=@var{file}
11451 Instead of querying substitutes for all the packages, only ask for those
11452 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
11453 with the @code{-m} option of @command{guix package} (@pxref{Invoking
11456 This option can be repeated several times, in which case the manifests
11459 @item --coverage[=@var{count}]
11460 @itemx -c [@var{count}]
11461 Report on substitute coverage for packages: list packages with at least
11462 @var{count} dependents (zero by default) for which substitutes are
11463 unavailable. Dependent packages themselves are not listed: if @var{b} depends
11464 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
11465 @var{b} usually lacks substitutes as well. The result looks like this:
11468 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
11469 computing 8,983 package derivations for x86_64-linux...
11470 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
11471 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
11472 @value{SUBSTITUTE-URL}
11473 64.7% substitutes available (6,047 out of 9,343)
11475 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
11476 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
11477 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
11478 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
11482 What this example shows is that @code{kcoreaddons} and presumably the 58
11483 packages that depend on it have no substitutes at @code{ci.guix.info};
11484 likewise for @code{qgpgme} and the 46 packages that depend on it.
11486 If you are a Guix developer, or if you are taking care of this build farm,
11487 you'll probably want to have a closer look at these packages: they may simply
11490 @item --display-missing
11491 Display the list of store items for which substitutes are missing.
11494 @node Invoking guix processes
11495 @section Invoking @command{guix processes}
11497 The @command{guix processes} command can be useful to developers and system
11498 administrators, especially on multi-user machines and on build farms: it lists
11499 the current sessions (connections to the daemon), as well as information about
11500 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
11501 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
11502 listed.}. Here's an example of the information it returns:
11505 $ sudo guix processes
11508 ClientCommand: guix environment --ad-hoc python
11512 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
11516 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
11517 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
11518 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
11519 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
11520 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
11521 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
11522 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
11525 In this example we see that @command{guix-daemon} has three clients:
11526 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
11527 integration tool; their process identifier (PID) is given by the
11528 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
11529 @command{guix-daemon} sub-process of this particular session.
11531 The @code{LockHeld} fields show which store items are currently locked by this
11532 session, which corresponds to store items being built or substituted (the
11533 @code{LockHeld} field is not displayed when @command{guix processes} is not
11534 running as root). Last, by looking at the @code{ChildProcess} field, we
11535 understand that these three builds are being offloaded (@pxref{Daemon Offload
11538 The output is in Recutils format so we can use the handy @command{recsel}
11539 command to select sessions of interest (@pxref{Selection Expressions,,,
11540 recutils, GNU recutils manual}). As an example, the command shows the command
11541 line and PID of the client that triggered the build of a Perl package:
11544 $ sudo guix processes | \
11545 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
11547 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
11550 @node System Configuration
11551 @chapter System Configuration
11553 @cindex system configuration
11554 Guix System supports a consistent whole-system configuration
11555 mechanism. By that we mean that all aspects of the global system
11556 configuration---such as the available system services, timezone and
11557 locale settings, user accounts---are declared in a single place. Such
11558 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
11560 One of the advantages of putting all the system configuration under the
11561 control of Guix is that it supports transactional system upgrades, and
11562 makes it possible to roll back to a previous system instantiation,
11563 should something go wrong with the new one (@pxref{Features}). Another
11564 advantage is that it makes it easy to replicate the exact same configuration
11565 across different machines, or at different points in time, without
11566 having to resort to additional administration tools layered on top of
11567 the own tools of the system.
11568 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
11570 This section describes this mechanism. First we focus on the system
11571 administrator's viewpoint---explaining how the system is configured and
11572 instantiated. Then we show how this mechanism can be extended, for
11573 instance to support new system services.
11576 * Using the Configuration System:: Customizing your GNU system.
11577 * operating-system Reference:: Detail of operating-system declarations.
11578 * File Systems:: Configuring file system mounts.
11579 * Mapped Devices:: Block device extra processing.
11580 * User Accounts:: Specifying user accounts.
11581 * Keyboard Layout:: How the system interprets key strokes.
11582 * Locales:: Language and cultural convention settings.
11583 * Services:: Specifying system services.
11584 * Setuid Programs:: Programs running with root privileges.
11585 * X.509 Certificates:: Authenticating HTTPS servers.
11586 * Name Service Switch:: Configuring libc's name service switch.
11587 * Initial RAM Disk:: Linux-Libre bootstrapping.
11588 * Bootloader Configuration:: Configuring the boot loader.
11589 * Invoking guix system:: Instantiating a system configuration.
11590 * Invoking guix deploy:: Deploying a system configuration to a remote host.
11591 * Running Guix in a VM:: How to run Guix System in a virtual machine.
11592 * Defining Services:: Adding new service definitions.
11595 @node Using the Configuration System
11596 @section Using the Configuration System
11598 The operating system is configured by providing an
11599 @code{operating-system} declaration in a file that can then be passed to
11600 the @command{guix system} command (@pxref{Invoking guix system}). A
11601 simple setup, with the default system services, the default Linux-Libre
11602 kernel, initial RAM disk, and boot loader looks like this:
11604 @findex operating-system
11606 @include os-config-bare-bones.texi
11609 This example should be self-describing. Some of the fields defined
11610 above, such as @code{host-name} and @code{bootloader}, are mandatory.
11611 Others, such as @code{packages} and @code{services}, can be omitted, in
11612 which case they get a default value.
11614 Below we discuss the effect of some of the most important fields
11615 (@pxref{operating-system Reference}, for details about all the available
11616 fields), and how to @dfn{instantiate} the operating system using
11617 @command{guix system}.
11619 @unnumberedsubsec Bootloader
11621 @cindex legacy boot, on Intel machines
11622 @cindex BIOS boot, on Intel machines
11625 The @code{bootloader} field describes the method that will be used to boot
11626 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
11627 mode, as in the example above. However, more recent machines rely instead on
11628 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
11629 the @code{bootloader} field should contain something along these lines:
11632 (bootloader-configuration
11633 (bootloader grub-efi-bootloader)
11634 (target "/boot/efi"))
11637 @xref{Bootloader Configuration}, for more information on the available
11638 configuration options.
11640 @unnumberedsubsec Globally-Visible Packages
11642 @vindex %base-packages
11643 The @code{packages} field lists packages that will be globally visible
11644 on the system, for all user accounts---i.e., in every user's @env{PATH}
11645 environment variable---in addition to the per-user profiles
11646 (@pxref{Invoking guix package}). The @code{%base-packages} variable
11647 provides all the tools one would expect for basic user and administrator
11648 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
11649 the GNU Zile lightweight text editor, @command{find}, @command{grep},
11650 etc. The example above adds GNU@tie{}Screen to those,
11651 taken from the @code{(gnu packages screen)}
11652 module (@pxref{Package Modules}). The
11653 @code{(list package output)} syntax can be used to add a specific output
11657 (use-modules (gnu packages))
11658 (use-modules (gnu packages dns))
11662 (packages (cons (list bind "utils")
11666 @findex specification->package
11667 Referring to packages by variable name, like @code{bind} above, has
11668 the advantage of being unambiguous; it also allows typos and such to be
11669 diagnosed right away as ``unbound variables''. The downside is that one
11670 needs to know which module defines which package, and to augment the
11671 @code{use-package-modules} line accordingly. To avoid that, one can use
11672 the @code{specification->package} procedure of the @code{(gnu packages)}
11673 module, which returns the best package for a given name or name and
11677 (use-modules (gnu packages))
11681 (packages (append (map specification->package
11682 '("tcpdump" "htop" "gnupg@@2.0"))
11686 @unnumberedsubsec System Services
11689 @vindex %base-services
11690 The @code{services} field lists @dfn{system services} to be made
11691 available when the system starts (@pxref{Services}).
11692 The @code{operating-system} declaration above specifies that, in
11693 addition to the basic services, we want the OpenSSH secure shell
11694 daemon listening on port 2222 (@pxref{Networking Services,
11695 @code{openssh-service-type}}). Under the hood,
11696 @code{openssh-service-type} arranges so that @command{sshd} is started with the
11697 right command-line options, possibly with supporting configuration files
11698 generated as needed (@pxref{Defining Services}).
11700 @cindex customization, of services
11701 @findex modify-services
11702 Occasionally, instead of using the base services as is, you will want to
11703 customize them. To do this, use @code{modify-services} (@pxref{Service
11704 Reference, @code{modify-services}}) to modify the list.
11706 For example, suppose you want to modify @code{guix-daemon} and Mingetty
11707 (the console log-in) in the @code{%base-services} list (@pxref{Base
11708 Services, @code{%base-services}}). To do that, you can write the
11709 following in your operating system declaration:
11712 (define %my-services
11713 ;; My very own list of services.
11714 (modify-services %base-services
11715 (guix-service-type config =>
11716 (guix-configuration
11718 (use-substitutes? #f)
11719 (extra-options '("--gc-keep-derivations"))))
11720 (mingetty-service-type config =>
11721 (mingetty-configuration
11722 (inherit config)))))
11726 (services %my-services))
11729 This changes the configuration---i.e., the service parameters---of the
11730 @code{guix-service-type} instance, and that of all the
11731 @code{mingetty-service-type} instances in the @code{%base-services} list.
11732 Observe how this is accomplished: first, we arrange for the original
11733 configuration to be bound to the identifier @code{config} in the
11734 @var{body}, and then we write the @var{body} so that it evaluates to the
11735 desired configuration. In particular, notice how we use @code{inherit}
11736 to create a new configuration which has the same values as the old
11737 configuration, but with a few modifications.
11739 @cindex encrypted disk
11740 The configuration for a typical ``desktop'' usage, with an encrypted
11741 root partition, the X11 display
11742 server, GNOME and Xfce (users can choose which of these desktop
11743 environments to use at the log-in screen by pressing @kbd{F1}), network
11744 management, power management, and more, would look like this:
11747 @include os-config-desktop.texi
11750 A graphical system with a choice of lightweight window managers
11751 instead of full-blown desktop environments would look like this:
11754 @include os-config-lightweight-desktop.texi
11757 This example refers to the @file{/boot/efi} file system by its UUID,
11758 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
11759 as returned by the @command{blkid} command.
11761 @xref{Desktop Services}, for the exact list of services provided by
11762 @code{%desktop-services}. @xref{X.509 Certificates}, for background
11763 information about the @code{nss-certs} package that is used here.
11765 Again, @code{%desktop-services} is just a list of service objects. If
11766 you want to remove services from there, you can do so using the
11767 procedures for list filtering (@pxref{SRFI-1 Filtering and
11768 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
11769 following expression returns a list that contains all the services in
11770 @code{%desktop-services} minus the Avahi service:
11773 (remove (lambda (service)
11774 (eq? (service-kind service) avahi-service-type))
11778 @unnumberedsubsec Instantiating the System
11780 Assuming the @code{operating-system} declaration
11781 is stored in the @file{my-system-config.scm}
11782 file, the @command{guix system reconfigure my-system-config.scm} command
11783 instantiates that configuration, and makes it the default GRUB boot
11784 entry (@pxref{Invoking guix system}).
11786 The normal way to change the system configuration is by updating this
11787 file and re-running @command{guix system reconfigure}. One should never
11788 have to touch files in @file{/etc} or to run commands that modify the
11789 system state such as @command{useradd} or @command{grub-install}. In
11790 fact, you must avoid that since that would not only void your warranty
11791 but also prevent you from rolling back to previous versions of your
11792 system, should you ever need to.
11794 @cindex roll-back, of the operating system
11795 Speaking of roll-back, each time you run @command{guix system
11796 reconfigure}, a new @dfn{generation} of the system is created---without
11797 modifying or deleting previous generations. Old system generations get
11798 an entry in the bootloader boot menu, allowing you to boot them in case
11799 something went wrong with the latest generation. Reassuring, no? The
11800 @command{guix system list-generations} command lists the system
11801 generations available on disk. It is also possible to roll back the
11802 system via the commands @command{guix system roll-back} and
11803 @command{guix system switch-generation}.
11805 Although the @command{guix system reconfigure} command will not modify
11806 previous generations, you must take care when the current generation is not
11807 the latest (e.g., after invoking @command{guix system roll-back}), since
11808 the operation might overwrite a later generation (@pxref{Invoking guix
11811 @unnumberedsubsec The Programming Interface
11813 At the Scheme level, the bulk of an @code{operating-system} declaration
11814 is instantiated with the following monadic procedure (@pxref{The Store
11817 @deffn {Monadic Procedure} operating-system-derivation os
11818 Return a derivation that builds @var{os}, an @code{operating-system}
11819 object (@pxref{Derivations}).
11821 The output of the derivation is a single directory that refers to all
11822 the packages, configuration files, and other supporting files needed to
11823 instantiate @var{os}.
11826 This procedure is provided by the @code{(gnu system)} module. Along
11827 with @code{(gnu services)} (@pxref{Services}), this module contains the
11828 guts of Guix System. Make sure to visit it!
11831 @node operating-system Reference
11832 @section @code{operating-system} Reference
11834 This section summarizes all the options available in
11835 @code{operating-system} declarations (@pxref{Using the Configuration
11838 @deftp {Data Type} operating-system
11839 This is the data type representing an operating system configuration.
11840 By that, we mean all the global system configuration, not per-user
11841 configuration (@pxref{Using the Configuration System}).
11844 @item @code{kernel} (default: @code{linux-libre})
11845 The package object of the operating system kernel to
11846 use@footnote{Currently only the Linux-libre kernel is fully supported.
11847 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
11848 available when building a virtual machine disk image.}.
11851 @item @code{hurd} (default: @code{#f})
11852 The package object of the hurd to be started by the kernel. When this
11853 field is set, produce a GNU/Hurd operating system. In that case,
11854 @code{kernel} must also be set to the @code{gnumach} package---the
11855 microkernel the Hurd runs on.
11858 This feature is experimental and only supported for disk images.
11861 @item @code{kernel-loadable-modules} (default: '())
11862 A list of objects (usually packages) to collect loadable kernel modules
11863 from--e.g. @code{(list ddcci-driver-linux)}.
11865 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
11866 List of strings or gexps representing additional arguments to pass on
11867 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
11869 @item @code{bootloader}
11870 The system bootloader configuration object. @xref{Bootloader Configuration}.
11873 This is the label (a string) as it appears in the bootloader's menu entry.
11874 The default label includes the kernel name and version.
11876 @item @code{keyboard-layout} (default: @code{#f})
11877 This field specifies the keyboard layout to use in the console. It can be
11878 either @code{#f}, in which case the default keyboard layout is used (usually
11879 US English), or a @code{<keyboard-layout>} record.
11881 This keyboard layout is in effect as soon as the kernel has booted. For
11882 instance, it is the keyboard layout in effect when you type a passphrase if
11883 your root file system is on a @code{luks-device-mapping} mapped device
11884 (@pxref{Mapped Devices}).
11887 This does @emph{not} specify the keyboard layout used by the bootloader, nor
11888 that used by the graphical display server. @xref{Bootloader Configuration},
11889 for information on how to specify the bootloader's keyboard layout. @xref{X
11890 Window}, for information on how to specify the keyboard layout used by the X
11894 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
11896 @cindex initial RAM disk
11897 The list of Linux kernel modules that need to be available in the
11898 initial RAM disk. @xref{Initial RAM Disk}.
11900 @item @code{initrd} (default: @code{base-initrd})
11901 A procedure that returns an initial RAM disk for the Linux
11902 kernel. This field is provided to support low-level customization and
11903 should rarely be needed for casual use. @xref{Initial RAM Disk}.
11905 @item @code{firmware} (default: @code{%base-firmware})
11907 List of firmware packages loadable by the operating system kernel.
11909 The default includes firmware needed for Atheros- and Broadcom-based
11910 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
11911 respectively). @xref{Hardware Considerations}, for more info on
11912 supported hardware.
11914 @item @code{host-name}
11917 @item @code{hosts-file}
11919 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
11920 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
11921 Reference Manual}). The default is a file with entries for
11922 @code{localhost} and @var{host-name}.
11924 @item @code{mapped-devices} (default: @code{'()})
11925 A list of mapped devices. @xref{Mapped Devices}.
11927 @item @code{file-systems}
11928 A list of file systems. @xref{File Systems}.
11930 @item @code{swap-devices} (default: @code{'()})
11931 @cindex swap devices
11932 A list of strings identifying devices or files to be used for ``swap
11933 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
11934 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
11935 It is possible to specify a swap file in a file system on a mapped
11936 device, provided that the necessary device mapping and file system are
11937 also specified. @xref{Mapped Devices} and @ref{File Systems}.
11939 @item @code{users} (default: @code{%base-user-accounts})
11940 @itemx @code{groups} (default: @code{%base-groups})
11941 List of user accounts and groups. @xref{User Accounts}.
11943 If the @code{users} list lacks a user account with UID@tie{}0, a
11944 ``root'' account with UID@tie{}0 is automatically added.
11946 @item @code{skeletons} (default: @code{(default-skeletons)})
11947 A list target file name/file-like object tuples (@pxref{G-Expressions,
11948 file-like objects}). These are the skeleton files that will be added to
11949 the home directory of newly-created user accounts.
11951 For instance, a valid value may look like this:
11954 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
11955 (".guile" ,(plain-file "guile"
11956 "(use-modules (ice-9 readline))
11957 (activate-readline)")))
11960 @item @code{issue} (default: @code{%default-issue})
11961 A string denoting the contents of the @file{/etc/issue} file, which is
11962 displayed when users log in on a text console.
11964 @item @code{packages} (default: @code{%base-packages})
11965 The set of packages installed in the global profile, which is accessible
11966 at @file{/run/current-system/profile}.
11968 The default set includes core utilities and it is good practice to
11969 install non-core utilities in user profiles (@pxref{Invoking guix
11972 @item @code{timezone}
11973 A timezone identifying string---e.g., @code{"Europe/Paris"}.
11975 You can run the @command{tzselect} command to find out which timezone
11976 string corresponds to your region. Choosing an invalid timezone name
11977 causes @command{guix system} to fail.
11979 @item @code{locale} (default: @code{"en_US.utf8"})
11980 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
11981 Library Reference Manual}). @xref{Locales}, for more information.
11983 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
11984 The list of locale definitions to be compiled and that may be used at
11985 run time. @xref{Locales}.
11987 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
11988 The list of GNU@tie{}libc packages whose locale data and tools are used
11989 to build the locale definitions. @xref{Locales}, for compatibility
11990 considerations that justify this option.
11992 @item @code{name-service-switch} (default: @code{%default-nss})
11993 Configuration of the libc name service switch (NSS)---a
11994 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
11997 @item @code{services} (default: @code{%base-services})
11998 A list of service objects denoting system services. @xref{Services}.
12000 @cindex essential services
12001 @item @code{essential-services} (default: ...)
12002 The list of ``essential services''---i.e., things like instances of
12003 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
12004 Reference}), which are derived from the operating system definition itself.
12005 As a user you should @emph{never} need to touch this field.
12007 @item @code{pam-services} (default: @code{(base-pam-services)})
12009 @cindex pluggable authentication modules
12010 Linux @dfn{pluggable authentication module} (PAM) services.
12011 @c FIXME: Add xref to PAM services section.
12013 @item @code{setuid-programs} (default: @code{%setuid-programs})
12014 List of string-valued G-expressions denoting setuid programs.
12015 @xref{Setuid Programs}.
12017 @item @code{sudoers-file} (default: @code{%sudoers-specification})
12018 @cindex sudoers file
12019 The contents of the @file{/etc/sudoers} file as a file-like object
12020 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
12022 This file specifies which users can use the @command{sudo} command, what
12023 they are allowed to do, and what privileges they may gain. The default
12024 is that only @code{root} and members of the @code{wheel} group may use
12029 @deffn {Scheme Syntax} this-operating-system
12030 When used in the @emph{lexical scope} of an operating system field definition,
12031 this identifier resolves to the operating system being defined.
12033 The example below shows how to refer to the operating system being defined in
12034 the definition of the @code{label} field:
12037 (use-modules (gnu) (guix))
12041 (label (package-full-name
12042 (operating-system-kernel this-operating-system))))
12045 It is an error to refer to @code{this-operating-system} outside an operating
12052 @section File Systems
12054 The list of file systems to be mounted is specified in the
12055 @code{file-systems} field of the operating system declaration
12056 (@pxref{Using the Configuration System}). Each file system is declared
12057 using the @code{file-system} form, like this:
12061 (mount-point "/home")
12062 (device "/dev/sda3")
12066 As usual, some of the fields are mandatory---those shown in the example
12067 above---while others can be omitted. These are described below.
12069 @deftp {Data Type} file-system
12070 Objects of this type represent file systems to be mounted. They
12071 contain the following members:
12075 This is a string specifying the type of the file system---e.g.,
12078 @item @code{mount-point}
12079 This designates the place where the file system is to be mounted.
12081 @item @code{device}
12082 This names the ``source'' of the file system. It can be one of three
12083 things: a file system label, a file system UUID, or the name of a
12084 @file{/dev} node. Labels and UUIDs offer a way to refer to file
12085 systems without having to hard-code their actual device
12086 name@footnote{Note that, while it is tempting to use
12087 @file{/dev/disk/by-uuid} and similar device names to achieve the same
12088 result, this is not recommended: These special device nodes are created
12089 by the udev daemon and may be unavailable at the time the device is
12092 @findex file-system-label
12093 File system labels are created using the @code{file-system-label}
12094 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
12095 plain strings. Here's an example of a file system referred to by its
12096 label, as shown by the @command{e2label} command:
12100 (mount-point "/home")
12102 (device (file-system-label "my-home")))
12106 UUIDs are converted from their string representation (as shown by the
12107 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
12108 @code{uuid} form expects 16-byte UUIDs as defined in
12109 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
12110 form of UUID used by the ext2 family of file systems and others, but it
12111 is different from ``UUIDs'' found in FAT file systems, for instance.},
12116 (mount-point "/home")
12118 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
12121 When the source of a file system is a mapped device (@pxref{Mapped
12122 Devices}), its @code{device} field @emph{must} refer to the mapped
12123 device name---e.g., @file{"/dev/mapper/root-partition"}.
12124 This is required so that
12125 the system knows that mounting the file system depends on having the
12126 corresponding device mapping established.
12128 @item @code{flags} (default: @code{'()})
12129 This is a list of symbols denoting mount flags. Recognized flags
12130 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
12131 access to special files), @code{no-suid} (ignore setuid and setgid
12132 bits), @code{no-atime} (do not update file access times),
12133 @code{strict-atime} (update file access time), @code{lazy-time} (only
12134 update time on the in-memory version of the file inode), and
12135 @code{no-exec} (disallow program execution).
12136 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
12137 Manual}, for more information on these flags.
12139 @item @code{options} (default: @code{#f})
12140 This is either @code{#f}, or a string denoting mount options passed to
12141 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
12142 Library Reference Manual}, for details and run @command{man 8 mount} for
12143 options for various file systems. Note that the
12144 @code{file-system-options->alist} and @code{alist->file-system-options}
12145 procedures from @code{(gnu system file-systems)} can be used to convert
12146 file system options given as an association list to the string
12147 representation, and vice-versa.
12149 @item @code{mount?} (default: @code{#t})
12150 This value indicates whether to automatically mount the file system when
12151 the system is brought up. When set to @code{#f}, the file system gets
12152 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
12153 is not automatically mounted.
12155 @item @code{needed-for-boot?} (default: @code{#f})
12156 This Boolean value indicates whether the file system is needed when
12157 booting. If that is true, then the file system is mounted when the
12158 initial RAM disk (initrd) is loaded. This is always the case, for
12159 instance, for the root file system.
12161 @item @code{check?} (default: @code{#t})
12162 This Boolean indicates whether the file system needs to be checked for
12163 errors before being mounted.
12165 @item @code{create-mount-point?} (default: @code{#f})
12166 When true, the mount point is created if it does not exist yet.
12168 @item @code{mount-may-fail?} (default: @code{#f})
12169 When true, this indicates that mounting this file system can fail but
12170 that should not be considered an error. This is useful in unusual
12171 cases; an example of this is @code{efivarfs}, a file system that can
12172 only be mounted on EFI/UEFI systems.
12174 @item @code{dependencies} (default: @code{'()})
12175 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
12176 representing file systems that must be mounted or mapped devices that
12177 must be opened before (and unmounted or closed after) this one.
12179 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
12180 a dependency of @file{/sys/fs/cgroup/cpu} and
12181 @file{/sys/fs/cgroup/memory}.
12183 Another example is a file system that depends on a mapped device, for
12184 example for an encrypted partition (@pxref{Mapped Devices}).
12188 The @code{(gnu system file-systems)} exports the following useful
12191 @defvr {Scheme Variable} %base-file-systems
12192 These are essential file systems that are required on normal systems,
12193 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
12194 below). Operating system declarations should always contain at least
12198 @defvr {Scheme Variable} %pseudo-terminal-file-system
12199 This is the file system to be mounted as @file{/dev/pts}. It supports
12200 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
12201 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
12202 Manual}). Pseudo-terminals are used by terminal emulators such as
12206 @defvr {Scheme Variable} %shared-memory-file-system
12207 This file system is mounted as @file{/dev/shm} and is used to support
12208 memory sharing across processes (@pxref{Memory-mapped I/O,
12209 @code{shm_open},, libc, The GNU C Library Reference Manual}).
12212 @defvr {Scheme Variable} %immutable-store
12213 This file system performs a read-only ``bind mount'' of
12214 @file{/gnu/store}, making it read-only for all the users including
12215 @code{root}. This prevents against accidental modification by software
12216 running as @code{root} or by system administrators.
12218 The daemon itself is still able to write to the store: it remounts it
12219 read-write in its own ``name space.''
12222 @defvr {Scheme Variable} %binary-format-file-system
12223 The @code{binfmt_misc} file system, which allows handling of arbitrary
12224 executable file types to be delegated to user space. This requires the
12225 @code{binfmt.ko} kernel module to be loaded.
12228 @defvr {Scheme Variable} %fuse-control-file-system
12229 The @code{fusectl} file system, which allows unprivileged users to mount
12230 and unmount user-space FUSE file systems. This requires the
12231 @code{fuse.ko} kernel module to be loaded.
12234 @node Btrfs file system
12235 @subsection Btrfs file system
12237 The Btrfs has special features, such as subvolumes, that merit being
12238 explained in more details. The following section attempts to cover
12239 basic as well as complex uses of a Btrfs file system with the Guix
12242 In its simplest usage, a Btrfs file system can be described, for
12247 (mount-point "/home")
12249 (device (file-system-label "my-home")))
12252 The example below is more complex, as it makes use of a Btrfs
12253 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
12254 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
12255 dependency on @code{mapped-devices}):
12259 (device (file-system-label "my-btrfs-pool"))
12262 (options "subvol=rootfs")
12263 (dependencies mapped-devices))
12266 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
12267 top level during the early boot, and rely on their configuration to
12268 refer to the correct subvolume path within that top level. The
12269 bootloaders operating in this way typically produce their configuration
12270 on a running system where the Btrfs partitions are already mounted and
12271 where the subvolume information is readily available. As an example,
12272 @command{grub-mkconfig}, the configuration generator command shipped
12273 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
12274 path of a subvolume.
12276 The Guix System produces a bootloader configuration using the operating
12277 system configuration as its sole input; it is therefore necessary to
12278 extract the subvolume name on which @file{/gnu/store} lives (if any)
12279 from that operating system configuration. To better illustrate,
12280 consider a subvolume named 'rootfs' which contains the root file system
12281 data. In such situation, the GRUB bootloader would only see the top
12282 level of the root Btrfs partition, e.g.:
12286 ├── rootfs (subvolume directory)
12287 ├── gnu (normal directory)
12288 ├── store (normal directory)
12292 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
12293 of the kernel, initrd binaries and any other files referred to in the
12294 GRUB configuration that must be found during the early boot.
12296 The next example shows a nested hierarchy of subvolumes and
12301 ├── rootfs (subvolume)
12302 ├── gnu (normal directory)
12303 ├── store (subvolume)
12307 This scenario would work without mounting the 'store' subvolume.
12308 Mounting 'rootfs' is sufficient, since the subvolume name matches its
12309 intended mount point in the file system hierarchy. Alternatively, the
12310 'store' subvolume could be referred to by setting the @code{subvol}
12311 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
12313 Finally, a more contrived example of nested subvolumes:
12317 ├── root-snapshots (subvolume)
12318 ├── root-current (subvolume)
12319 ├── guix-store (subvolume)
12323 Here, the 'guix-store' subvolume doesn't match its intended mount point,
12324 so it is necessary to mount it. The subvolume must be fully specified,
12325 by passing its file name to the @code{subvol} option. To illustrate,
12326 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
12327 a file system declaration such as:
12331 (device (file-system-label "btrfs-pool-1"))
12332 (mount-point "/gnu/store")
12334 (options "subvol=root-snapshots/root-current/guix-store,\
12335 compress-force=zstd,space_cache=v2"))
12338 @node Mapped Devices
12339 @section Mapped Devices
12341 @cindex device mapping
12342 @cindex mapped devices
12343 The Linux kernel has a notion of @dfn{device mapping}: a block device,
12344 such as a hard disk partition, can be @dfn{mapped} into another device,
12345 usually in @code{/dev/mapper/},
12346 with additional processing over the data that flows through
12347 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
12348 concept of a ``mapped device'' and that of a file system: both boil down
12349 to @emph{translating} input/output operations made on a file to
12350 operations on its backing store. Thus, the Hurd implements mapped
12351 devices, like file systems, using the generic @dfn{translator} mechanism
12352 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
12353 typical example is encryption device mapping: all writes to the mapped
12354 device are encrypted, and all reads are deciphered, transparently.
12355 Guix extends this notion by considering any device or set of devices that
12356 are @dfn{transformed} in some way to create a new device; for instance,
12357 RAID devices are obtained by @dfn{assembling} several other devices, such
12358 as hard disks or partitions, into a new one that behaves as one partition.
12359 Other examples, not yet implemented, are LVM logical volumes.
12361 Mapped devices are declared using the @code{mapped-device} form,
12362 defined as follows; for examples, see below.
12364 @deftp {Data Type} mapped-device
12365 Objects of this type represent device mappings that will be made when
12366 the system boots up.
12370 This is either a string specifying the name of the block device to be mapped,
12371 such as @code{"/dev/sda3"}, or a list of such strings when several devices
12372 need to be assembled for creating a new one.
12375 This string specifies the name of the resulting mapped device. For
12376 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
12377 specifying @code{"my-partition"} leads to the creation of
12378 the @code{"/dev/mapper/my-partition"} device.
12379 For RAID devices of type @code{raid-device-mapping}, the full device name
12380 such as @code{"/dev/md0"} needs to be given.
12383 This must be a @code{mapped-device-kind} object, which specifies how
12384 @var{source} is mapped to @var{target}.
12388 @defvr {Scheme Variable} luks-device-mapping
12389 This defines LUKS block device encryption using the @command{cryptsetup}
12390 command from the package with the same name. It relies on the
12391 @code{dm-crypt} Linux kernel module.
12394 @defvr {Scheme Variable} raid-device-mapping
12395 This defines a RAID device, which is assembled using the @code{mdadm}
12396 command from the package with the same name. It requires a Linux kernel
12397 module for the appropriate RAID level to be loaded, such as @code{raid456}
12398 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
12401 @cindex disk encryption
12403 The following example specifies a mapping from @file{/dev/sda3} to
12404 @file{/dev/mapper/home} using LUKS---the
12405 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
12406 standard mechanism for disk encryption.
12407 The @file{/dev/mapper/home}
12408 device can then be used as the @code{device} of a @code{file-system}
12409 declaration (@pxref{File Systems}).
12413 (source "/dev/sda3")
12415 (type luks-device-mapping))
12418 Alternatively, to become independent of device numbering, one may obtain
12419 the LUKS UUID (@dfn{unique identifier}) of the source device by a
12423 cryptsetup luksUUID /dev/sda3
12426 and use it as follows:
12430 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
12432 (type luks-device-mapping))
12435 @cindex swap encryption
12436 It is also desirable to encrypt swap space, since swap space may contain
12437 sensitive data. One way to accomplish that is to use a swap file in a
12438 file system on a device mapped via LUKS encryption. In this way, the
12439 swap file is encrypted because the entire device is encrypted.
12440 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
12442 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
12443 may be declared as follows:
12447 (source (list "/dev/sda1" "/dev/sdb1"))
12448 (target "/dev/md0")
12449 (type raid-device-mapping))
12452 The @file{/dev/md0} device can then be used as the @code{device} of a
12453 @code{file-system} declaration (@pxref{File Systems}).
12454 Note that the RAID level need not be given; it is chosen during the
12455 initial creation and formatting of the RAID device and is determined
12456 automatically later.
12459 @node User Accounts
12460 @section User Accounts
12464 @cindex user accounts
12465 User accounts and groups are entirely managed through the
12466 @code{operating-system} declaration. They are specified with the
12467 @code{user-account} and @code{user-group} forms:
12473 (supplementary-groups '("wheel" ;allow use of sudo, etc.
12474 "audio" ;sound card
12475 "video" ;video devices such as webcams
12476 "cdrom")) ;the good ol' CD-ROM
12477 (comment "Bob's sister")
12478 (home-directory "/home/alice"))
12481 When booting or upon completion of @command{guix system reconfigure},
12482 the system ensures that only the user accounts and groups specified in
12483 the @code{operating-system} declaration exist, and with the specified
12484 properties. Thus, account or group creations or modifications made by
12485 directly invoking commands such as @command{useradd} are lost upon
12486 reconfiguration or reboot. This ensures that the system remains exactly
12489 @deftp {Data Type} user-account
12490 Objects of this type represent user accounts. The following members may
12495 The name of the user account.
12499 This is the name (a string) or identifier (a number) of the user group
12500 this account belongs to.
12502 @item @code{supplementary-groups} (default: @code{'()})
12503 Optionally, this can be defined as a list of group names that this
12504 account belongs to.
12506 @item @code{uid} (default: @code{#f})
12507 This is the user ID for this account (a number), or @code{#f}. In the
12508 latter case, a number is automatically chosen by the system when the
12509 account is created.
12511 @item @code{comment} (default: @code{""})
12512 A comment about the account, such as the account owner's full name.
12514 @item @code{home-directory}
12515 This is the name of the home directory for the account.
12517 @item @code{create-home-directory?} (default: @code{#t})
12518 Indicates whether the home directory of this account should be created
12519 if it does not exist yet.
12521 @item @code{shell} (default: Bash)
12522 This is a G-expression denoting the file name of a program to be used as
12523 the shell (@pxref{G-Expressions}).
12525 @item @code{system?} (default: @code{#f})
12526 This Boolean value indicates whether the account is a ``system''
12527 account. System accounts are sometimes treated specially; for instance,
12528 graphical login managers do not list them.
12530 @anchor{user-account-password}
12531 @cindex password, for user accounts
12532 @item @code{password} (default: @code{#f})
12533 You would normally leave this field to @code{#f}, initialize user
12534 passwords as @code{root} with the @command{passwd} command, and then let
12535 users change it with @command{passwd}. Passwords set with
12536 @command{passwd} are of course preserved across reboot and
12539 If you @emph{do} want to set an initial password for an account, then
12540 this field must contain the encrypted password, as a string. You can use the
12541 @code{crypt} procedure for this purpose:
12548 ;; Specify a SHA-512-hashed initial password.
12549 (password (crypt "InitialPassword!" "$6$abc")))
12553 The hash of this initial password will be available in a file in
12554 @file{/gnu/store}, readable by all the users, so this method must be used with
12558 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
12559 more information on password encryption, and @ref{Encryption,,, guile, GNU
12560 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
12566 User group declarations are even simpler:
12569 (user-group (name "students"))
12572 @deftp {Data Type} user-group
12573 This type is for, well, user groups. There are just a few fields:
12577 The name of the group.
12579 @item @code{id} (default: @code{#f})
12580 The group identifier (a number). If @code{#f}, a new number is
12581 automatically allocated when the group is created.
12583 @item @code{system?} (default: @code{#f})
12584 This Boolean value indicates whether the group is a ``system'' group.
12585 System groups have low numerical IDs.
12587 @item @code{password} (default: @code{#f})
12588 What, user groups can have a password? Well, apparently yes. Unless
12589 @code{#f}, this field specifies the password of the group.
12594 For convenience, a variable lists all the basic user groups one may
12597 @defvr {Scheme Variable} %base-groups
12598 This is the list of basic user groups that users and/or packages expect
12599 to be present on the system. This includes groups such as ``root'',
12600 ``wheel'', and ``users'', as well as groups used to control access to
12601 specific devices such as ``audio'', ``disk'', and ``cdrom''.
12604 @defvr {Scheme Variable} %base-user-accounts
12605 This is the list of basic system accounts that programs may expect to
12606 find on a GNU/Linux system, such as the ``nobody'' account.
12608 Note that the ``root'' account is not included here. It is a
12609 special-case and is automatically added whether or not it is specified.
12612 @node Keyboard Layout
12613 @section Keyboard Layout
12615 @cindex keyboard layout
12617 To specify what each key of your keyboard does, you need to tell the operating
12618 system what @dfn{keyboard layout} you want to use. The default, when nothing
12619 is specified, is the US English QWERTY layout for 105-key PC keyboards.
12620 However, German speakers will usually prefer the German QWERTZ layout, French
12621 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
12622 or bépo, and they might even want to further customize the effect of some of
12623 the keys. This section explains how to get that done.
12625 @cindex keyboard layout, definition
12626 There are three components that will want to know about your keyboard layout:
12630 The @emph{bootloader} may want to know what keyboard layout you want to use
12631 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
12632 you want, for instance, to make sure that you can type the passphrase of your
12633 encrypted root partition using the right layout.
12636 The @emph{operating system kernel}, Linux, will need that so that the console
12637 is properly configured (@pxref{operating-system Reference,
12638 @code{keyboard-layout}}).
12641 The @emph{graphical display server}, usually Xorg, also has its own idea of
12642 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
12645 Guix allows you to configure all three separately but, fortunately, it allows
12646 you to share the same keyboard layout for all three components.
12648 @cindex XKB, keyboard layouts
12649 Keyboard layouts are represented by records created by the
12650 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
12651 the X Keyboard extension (XKB), each layout has four attributes: a name (often
12652 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
12653 optional variant name, an optional keyboard model name, and a possibly empty
12654 list of additional options. In most cases the layout name is all you care
12655 about. Here are a few example:
12658 ;; The German QWERTZ layout. Here we assume a standard
12659 ;; "pc105" keyboard model.
12660 (keyboard-layout "de")
12662 ;; The bépo variant of the French layout.
12663 (keyboard-layout "fr" "bepo")
12665 ;; The Catalan layout.
12666 (keyboard-layout "es" "cat")
12668 ;; Arabic layout with "Alt-Shift" to switch to US layout.
12669 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
12671 ;; The Latin American Spanish layout. In addition, the
12672 ;; "Caps Lock" key is used as an additional "Ctrl" key,
12673 ;; and the "Menu" key is used as a "Compose" key to enter
12674 ;; accented letters.
12675 (keyboard-layout "latam"
12676 #:options '("ctrl:nocaps" "compose:menu"))
12678 ;; The Russian layout for a ThinkPad keyboard.
12679 (keyboard-layout "ru" #:model "thinkpad")
12681 ;; The "US international" layout, which is the US layout plus
12682 ;; dead keys to enter accented characters. This is for an
12683 ;; Apple MacBook keyboard.
12684 (keyboard-layout "us" "intl" #:model "macbook78")
12687 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
12688 for a complete list of supported layouts, variants, and models.
12690 @cindex keyboard layout, configuration
12691 Let's say you want your system to use the Turkish keyboard layout throughout
12692 your system---bootloader, console, and Xorg. Here's what your system
12693 configuration would look like:
12695 @findex set-xorg-configuration
12697 ;; Using the Turkish layout for the bootloader, the console,
12702 (keyboard-layout (keyboard-layout "tr")) ;for the console
12703 (bootloader (bootloader-configuration
12704 (bootloader grub-efi-bootloader)
12705 (target "/boot/efi")
12706 (keyboard-layout keyboard-layout))) ;for GRUB
12707 (services (cons (set-xorg-configuration
12708 (xorg-configuration ;for Xorg
12709 (keyboard-layout keyboard-layout)))
12710 %desktop-services)))
12713 In the example above, for GRUB and for Xorg, we just refer to the
12714 @code{keyboard-layout} field defined above, but we could just as well refer to
12715 a different layout. The @code{set-xorg-configuration} procedure communicates
12716 the desired Xorg configuration to the graphical log-in manager, by default
12719 We've discussed how to specify the @emph{default} keyboard layout of your
12720 system when it starts, but you can also adjust it at run time:
12724 If you're using GNOME, its settings panel has a ``Region & Language'' entry
12725 where you can select one or more keyboard layouts.
12728 Under Xorg, the @command{setxkbmap} command (from the same-named package)
12729 allows you to change the current layout. For example, this is how you would
12730 change the layout to US Dvorak:
12733 setxkbmap us dvorak
12737 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
12738 console. However, note that @code{loadkeys} does @emph{not} use the XKB
12739 keyboard layout categorization described above. The command below loads the
12740 French bépo layout:
12751 A @dfn{locale} defines cultural conventions for a particular language
12752 and region of the world (@pxref{Locales,,, libc, The GNU C Library
12753 Reference Manual}). Each locale has a name that typically has the form
12754 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
12755 @code{fr_LU.utf8} designates the locale for the French language, with
12756 cultural conventions from Luxembourg, and using the UTF-8 encoding.
12758 @cindex locale definition
12759 Usually, you will want to specify the default locale for the machine
12760 using the @code{locale} field of the @code{operating-system} declaration
12761 (@pxref{operating-system Reference, @code{locale}}).
12763 The selected locale is automatically added to the @dfn{locale
12764 definitions} known to the system if needed, with its codeset inferred
12765 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
12766 @code{UTF-8} codeset. Additional locale definitions can be specified in
12767 the @code{locale-definitions} slot of @code{operating-system}---this is
12768 useful, for instance, if the codeset could not be inferred from the
12769 locale name. The default set of locale definitions includes some widely
12770 used locales, but not all the available locales, in order to save space.
12772 For instance, to add the North Frisian locale for Germany, the value of
12776 (cons (locale-definition
12777 (name "fy_DE.utf8") (source "fy_DE"))
12778 %default-locale-definitions)
12781 Likewise, to save space, one might want @code{locale-definitions} to
12782 list only the locales that are actually used, as in:
12785 (list (locale-definition
12786 (name "ja_JP.eucjp") (source "ja_JP")
12787 (charset "EUC-JP")))
12791 The compiled locale definitions are available at
12792 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
12793 version, which is the default location where the GNU@tie{}libc provided
12794 by Guix looks for locale data. This can be overridden using the
12795 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
12796 @env{LOCPATH} and locale packages}).
12798 The @code{locale-definition} form is provided by the @code{(gnu system
12799 locale)} module. Details are given below.
12801 @deftp {Data Type} locale-definition
12802 This is the data type of a locale definition.
12807 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
12808 Reference Manual}, for more information on locale names.
12810 @item @code{source}
12811 The name of the source for that locale. This is typically the
12812 @code{@var{language}_@var{territory}} part of the locale name.
12814 @item @code{charset} (default: @code{"UTF-8"})
12815 The ``character set'' or ``code set'' for that locale,
12816 @uref{https://www.iana.org/assignments/character-sets, as defined by
12822 @defvr {Scheme Variable} %default-locale-definitions
12823 A list of commonly used UTF-8 locales, used as the default
12824 value of the @code{locale-definitions} field of @code{operating-system}
12827 @cindex locale name
12828 @cindex normalized codeset in locale names
12829 These locale definitions use the @dfn{normalized codeset} for the part
12830 that follows the dot in the name (@pxref{Using gettextized software,
12831 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
12832 instance it has @code{uk_UA.utf8} but @emph{not}, say,
12833 @code{uk_UA.UTF-8}.
12836 @subsection Locale Data Compatibility Considerations
12838 @cindex incompatibility, of locale data
12839 @code{operating-system} declarations provide a @code{locale-libcs} field
12840 to specify the GNU@tie{}libc packages that are used to compile locale
12841 declarations (@pxref{operating-system Reference}). ``Why would I
12842 care?'', you may ask. Well, it turns out that the binary format of
12843 locale data is occasionally incompatible from one libc version to
12846 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
12847 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
12848 For instance, a program linked against libc version 2.21 is unable to
12849 read locale data produced with libc 2.22; worse, that program
12850 @emph{aborts} instead of simply ignoring the incompatible locale
12851 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
12852 the incompatible locale data, which is already an improvement.}.
12853 Similarly, a program linked against libc 2.22 can read most, but not
12854 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
12855 data is incompatible); thus calls to @code{setlocale} may fail, but
12856 programs will not abort.
12858 The ``problem'' with Guix is that users have a lot of freedom: They can
12859 choose whether and when to upgrade software in their profiles, and might
12860 be using a libc version different from the one the system administrator
12861 used to build the system-wide locale data.
12863 Fortunately, unprivileged users can also install their own locale data
12864 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
12865 @env{GUIX_LOCPATH} and locale packages}).
12867 Still, it is best if the system-wide locale data at
12868 @file{/run/current-system/locale} is built for all the libc versions
12869 actually in use on the system, so that all the programs can access
12870 it---this is especially crucial on a multi-user system. To do that, the
12871 administrator can specify several libc packages in the
12872 @code{locale-libcs} field of @code{operating-system}:
12875 (use-package-modules base)
12879 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
12882 This example would lead to a system containing locale definitions for
12883 both libc 2.21 and the current version of libc in
12884 @file{/run/current-system/locale}.
12890 @cindex system services
12891 An important part of preparing an @code{operating-system} declaration is
12892 listing @dfn{system services} and their configuration (@pxref{Using the
12893 Configuration System}). System services are typically daemons launched
12894 when the system boots, or other actions needed at that time---e.g.,
12895 configuring network access.
12897 Guix has a broad definition of ``service'' (@pxref{Service
12898 Composition}), but many services are managed by the GNU@tie{}Shepherd
12899 (@pxref{Shepherd Services}). On a running system, the @command{herd}
12900 command allows you to list the available services, show their status,
12901 start and stop them, or do other specific operations (@pxref{Jump
12902 Start,,, shepherd, The GNU Shepherd Manual}). For example:
12908 The above command, run as @code{root}, lists the currently defined
12909 services. The @command{herd doc} command shows a synopsis of the given
12910 service and its associated actions:
12914 Run libc's name service cache daemon (nscd).
12916 # herd doc nscd action invalidate
12917 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
12920 The @command{start}, @command{stop}, and @command{restart} sub-commands
12921 have the effect you would expect. For instance, the commands below stop
12922 the nscd service and restart the Xorg display server:
12926 Service nscd has been stopped.
12927 # herd restart xorg-server
12928 Service xorg-server has been stopped.
12929 Service xorg-server has been started.
12932 The following sections document the available services, starting with
12933 the core services, that may be used in an @code{operating-system}
12937 * Base Services:: Essential system services.
12938 * Scheduled Job Execution:: The mcron service.
12939 * Log Rotation:: The rottlog service.
12940 * Networking Services:: Network setup, SSH daemon, etc.
12941 * Unattended Upgrades:: Automated system upgrades.
12942 * X Window:: Graphical display.
12943 * Printing Services:: Local and remote printer support.
12944 * Desktop Services:: D-Bus and desktop services.
12945 * Sound Services:: ALSA and Pulseaudio services.
12946 * Database Services:: SQL databases, key-value stores, etc.
12947 * Mail Services:: IMAP, POP3, SMTP, and all that.
12948 * Messaging Services:: Messaging services.
12949 * Telephony Services:: Telephony services.
12950 * Monitoring Services:: Monitoring services.
12951 * Kerberos Services:: Kerberos services.
12952 * LDAP Services:: LDAP services.
12953 * Web Services:: Web servers.
12954 * Certificate Services:: TLS certificates via Let's Encrypt.
12955 * DNS Services:: DNS daemons.
12956 * VPN Services:: VPN daemons.
12957 * Network File System:: NFS related services.
12958 * Continuous Integration:: The Cuirass service.
12959 * Power Management Services:: Extending battery life.
12960 * Audio Services:: The MPD.
12961 * Virtualization Services:: Virtualization services.
12962 * Version Control Services:: Providing remote access to Git repositories.
12963 * Game Services:: Game servers.
12964 * PAM Mount Service:: Service to mount volumes when logging in.
12965 * Guix Services:: Services relating specifically to Guix.
12966 * Linux Services:: Services tied to the Linux kernel.
12967 * Hurd Services:: Services specific for a Hurd System.
12968 * Miscellaneous Services:: Other services.
12971 @node Base Services
12972 @subsection Base Services
12974 The @code{(gnu services base)} module provides definitions for the basic
12975 services that one expects from the system. The services exported by
12976 this module are listed below.
12978 @defvr {Scheme Variable} %base-services
12979 This variable contains a list of basic services (@pxref{Service Types
12980 and Services}, for more information on service objects) one would
12981 expect from the system: a login service (mingetty) on each tty, syslogd,
12982 the libc name service cache daemon (nscd), the udev device manager, and
12985 This is the default value of the @code{services} field of
12986 @code{operating-system} declarations. Usually, when customizing a
12987 system, you will want to append services to @code{%base-services}, like
12991 (append (list (service avahi-service-type)
12992 (service openssh-service-type))
12997 @defvr {Scheme Variable} special-files-service-type
12998 This is the service that sets up ``special files'' such as
12999 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
13001 The value associated with @code{special-files-service-type} services
13002 must be a list of tuples where the first element is the ``special file''
13003 and the second element is its target. By default it is:
13005 @cindex @file{/bin/sh}
13006 @cindex @file{sh}, in @file{/bin}
13008 `(("/bin/sh" ,(file-append bash "/bin/sh")))
13011 @cindex @file{/usr/bin/env}
13012 @cindex @file{env}, in @file{/usr/bin}
13013 If you want to add, say, @code{/usr/bin/env} to your system, you can
13017 `(("/bin/sh" ,(file-append bash "/bin/sh"))
13018 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
13021 Since this is part of @code{%base-services}, you can use
13022 @code{modify-services} to customize the set of special files
13023 (@pxref{Service Reference, @code{modify-services}}). But the simple way
13024 to add a special file is @i{via} the @code{extra-special-file} procedure
13028 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
13029 Use @var{target} as the ``special file'' @var{file}.
13031 For example, adding the following lines to the @code{services} field of
13032 your operating system declaration leads to a @file{/usr/bin/env}
13036 (extra-special-file "/usr/bin/env"
13037 (file-append coreutils "/bin/env"))
13041 @deffn {Scheme Procedure} host-name-service @var{name}
13042 Return a service that sets the host name to @var{name}.
13045 @defvr {Scheme Variable} console-font-service-type
13046 Install the given fonts on the specified ttys (fonts are per
13047 virtual console on the kernel Linux). The value of this service is a list of
13048 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
13049 package or any valid argument to @command{setfont}, as in this example:
13052 `(("tty1" . "LatGrkCyr-8x16")
13053 ("tty2" . ,(file-append
13055 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
13056 ("tty3" . ,(file-append
13058 "/share/consolefonts/ter-132n"))) ; for HDPI
13062 @deffn {Scheme Procedure} login-service @var{config}
13063 Return a service to run login according to @var{config}, a
13064 @code{<login-configuration>} object, which specifies the message of the day,
13065 among other things.
13068 @deftp {Data Type} login-configuration
13069 This is the data type representing the configuration of login.
13074 @cindex message of the day
13075 A file-like object containing the ``message of the day''.
13077 @item @code{allow-empty-passwords?} (default: @code{#t})
13078 Allow empty passwords by default so that first-time users can log in when
13079 the 'root' account has just been created.
13084 @deffn {Scheme Procedure} mingetty-service @var{config}
13085 Return a service to run mingetty according to @var{config}, a
13086 @code{<mingetty-configuration>} object, which specifies the tty to run, among
13090 @deftp {Data Type} mingetty-configuration
13091 This is the data type representing the configuration of Mingetty, which
13092 provides the default implementation of virtual console log-in.
13097 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
13099 @item @code{auto-login} (default: @code{#f})
13100 When true, this field must be a string denoting the user name under
13101 which the system automatically logs in. When it is @code{#f}, a
13102 user name and password must be entered to log in.
13104 @item @code{login-program} (default: @code{#f})
13105 This must be either @code{#f}, in which case the default log-in program
13106 is used (@command{login} from the Shadow tool suite), or a gexp denoting
13107 the name of the log-in program.
13109 @item @code{login-pause?} (default: @code{#f})
13110 When set to @code{#t} in conjunction with @var{auto-login}, the user
13111 will have to press a key before the log-in shell is launched.
13113 @item @code{mingetty} (default: @var{mingetty})
13114 The Mingetty package to use.
13119 @deffn {Scheme Procedure} agetty-service @var{config}
13120 Return a service to run agetty according to @var{config}, an
13121 @code{<agetty-configuration>} object, which specifies the tty to run,
13122 among other things.
13125 @deftp {Data Type} agetty-configuration
13126 This is the data type representing the configuration of agetty, which
13127 implements virtual and serial console log-in. See the @code{agetty(8)}
13128 man page for more information.
13133 The name of the console this agetty runs on, as a string---e.g.,
13134 @code{"ttyS0"}. This argument is optional, it will default to
13135 a reasonable default serial port used by the kernel Linux.
13137 For this, if there is a value for an option @code{agetty.tty} in the kernel
13138 command line, agetty will extract the device name of the serial port
13139 from it and use that.
13141 If not and if there is a value for an option @code{console} with a tty in
13142 the Linux command line, agetty will extract the device name of the
13143 serial port from it and use that.
13145 In both cases, agetty will leave the other serial device settings
13146 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
13149 @item @code{baud-rate} (default: @code{#f})
13150 A string containing a comma-separated list of one or more baud rates, in
13153 @item @code{term} (default: @code{#f})
13154 A string containing the value used for the @env{TERM} environment
13157 @item @code{eight-bits?} (default: @code{#f})
13158 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
13161 @item @code{auto-login} (default: @code{#f})
13162 When passed a login name, as a string, the specified user will be logged
13163 in automatically without prompting for their login name or password.
13165 @item @code{no-reset?} (default: @code{#f})
13166 When @code{#t}, don't reset terminal cflags (control modes).
13168 @item @code{host} (default: @code{#f})
13169 This accepts a string containing the ``login_host'', which will be written
13170 into the @file{/var/run/utmpx} file.
13172 @item @code{remote?} (default: @code{#f})
13173 When set to @code{#t} in conjunction with @var{host}, this will add an
13174 @code{-r} fakehost option to the command line of the login program
13175 specified in @var{login-program}.
13177 @item @code{flow-control?} (default: @code{#f})
13178 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
13180 @item @code{no-issue?} (default: @code{#f})
13181 When set to @code{#t}, the contents of the @file{/etc/issue} file will
13182 not be displayed before presenting the login prompt.
13184 @item @code{init-string} (default: @code{#f})
13185 This accepts a string that will be sent to the tty or modem before
13186 sending anything else. It can be used to initialize a modem.
13188 @item @code{no-clear?} (default: @code{#f})
13189 When set to @code{#t}, agetty will not clear the screen before showing
13192 @item @code{login-program} (default: (file-append shadow "/bin/login"))
13193 This must be either a gexp denoting the name of a log-in program, or
13194 unset, in which case the default value is the @command{login} from the
13197 @item @code{local-line} (default: @code{#f})
13198 Control the CLOCAL line flag. This accepts one of three symbols as
13199 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
13200 the default value chosen by agetty is @code{'auto}.
13202 @item @code{extract-baud?} (default: @code{#f})
13203 When set to @code{#t}, instruct agetty to try to extract the baud rate
13204 from the status messages produced by certain types of modems.
13206 @item @code{skip-login?} (default: @code{#f})
13207 When set to @code{#t}, do not prompt the user for a login name. This
13208 can be used with @var{login-program} field to use non-standard login
13211 @item @code{no-newline?} (default: @code{#f})
13212 When set to @code{#t}, do not print a newline before printing the
13213 @file{/etc/issue} file.
13215 @c Is this dangerous only when used with login-program, or always?
13216 @item @code{login-options} (default: @code{#f})
13217 This option accepts a string containing options that are passed to the
13218 login program. When used with the @var{login-program}, be aware that a
13219 malicious user could try to enter a login name containing embedded
13220 options that could be parsed by the login program.
13222 @item @code{login-pause} (default: @code{#f})
13223 When set to @code{#t}, wait for any key before showing the login prompt.
13224 This can be used in conjunction with @var{auto-login} to save memory by
13225 lazily spawning shells.
13227 @item @code{chroot} (default: @code{#f})
13228 Change root to the specified directory. This option accepts a directory
13231 @item @code{hangup?} (default: @code{#f})
13232 Use the Linux system call @code{vhangup} to do a virtual hangup of the
13233 specified terminal.
13235 @item @code{keep-baud?} (default: @code{#f})
13236 When set to @code{#t}, try to keep the existing baud rate. The baud
13237 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
13240 @item @code{timeout} (default: @code{#f})
13241 When set to an integer value, terminate if no user name could be read
13242 within @var{timeout} seconds.
13244 @item @code{detect-case?} (default: @code{#f})
13245 When set to @code{#t}, turn on support for detecting an uppercase-only
13246 terminal. This setting will detect a login name containing only
13247 uppercase letters as indicating an uppercase-only terminal and turn on
13248 some upper-to-lower case conversions. Note that this will not support
13249 Unicode characters.
13251 @item @code{wait-cr?} (default: @code{#f})
13252 When set to @code{#t}, wait for the user or modem to send a
13253 carriage-return or linefeed character before displaying
13254 @file{/etc/issue} or login prompt. This is typically used with the
13255 @var{init-string} option.
13257 @item @code{no-hints?} (default: @code{#f})
13258 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
13261 @item @code{no-hostname?} (default: @code{#f})
13262 By default, the hostname is printed. When this option is set to
13263 @code{#t}, no hostname will be shown at all.
13265 @item @code{long-hostname?} (default: @code{#f})
13266 By default, the hostname is only printed until the first dot. When this
13267 option is set to @code{#t}, the fully qualified hostname by
13268 @code{gethostname} or @code{getaddrinfo} is shown.
13270 @item @code{erase-characters} (default: @code{#f})
13271 This option accepts a string of additional characters that should be
13272 interpreted as backspace when the user types their login name.
13274 @item @code{kill-characters} (default: @code{#f})
13275 This option accepts a string that should be interpreted to mean ``ignore
13276 all previous characters'' (also called a ``kill'' character) when the user
13277 types their login name.
13279 @item @code{chdir} (default: @code{#f})
13280 This option accepts, as a string, a directory path that will be changed
13283 @item @code{delay} (default: @code{#f})
13284 This options accepts, as an integer, the number of seconds to sleep
13285 before opening the tty and displaying the login prompt.
13287 @item @code{nice} (default: @code{#f})
13288 This option accepts, as an integer, the nice value with which to run the
13289 @command{login} program.
13291 @item @code{extra-options} (default: @code{'()})
13292 This option provides an ``escape hatch'' for the user to provide arbitrary
13293 command-line arguments to @command{agetty} as a list of strings.
13298 @deffn {Scheme Procedure} kmscon-service-type @var{config}
13299 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
13300 according to @var{config}, a @code{<kmscon-configuration>} object, which
13301 specifies the tty to run, among other things.
13304 @deftp {Data Type} kmscon-configuration
13305 This is the data type representing the configuration of Kmscon, which
13306 implements virtual console log-in.
13310 @item @code{virtual-terminal}
13311 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
13313 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
13314 A gexp denoting the name of the log-in program. The default log-in program is
13315 @command{login} from the Shadow tool suite.
13317 @item @code{login-arguments} (default: @code{'("-p")})
13318 A list of arguments to pass to @command{login}.
13320 @item @code{auto-login} (default: @code{#f})
13321 When passed a login name, as a string, the specified user will be logged
13322 in automatically without prompting for their login name or password.
13324 @item @code{hardware-acceleration?} (default: #f)
13325 Whether to use hardware acceleration.
13327 @item @code{kmscon} (default: @var{kmscon})
13328 The Kmscon package to use.
13333 @cindex name service cache daemon
13335 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
13336 [#:name-services '()]
13337 Return a service that runs the libc name service cache daemon (nscd) with the
13338 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
13339 Service Switch}, for an example.
13341 For convenience, the Shepherd service for nscd provides the following actions:
13345 @cindex cache invalidation, nscd
13346 @cindex nscd, cache invalidation
13347 This invalidate the given cache. For instance, running:
13350 herd invalidate nscd hosts
13354 invalidates the host name lookup cache of nscd.
13357 Running @command{herd statistics nscd} displays information about nscd usage
13363 @defvr {Scheme Variable} %nscd-default-configuration
13364 This is the default @code{<nscd-configuration>} value (see below) used
13365 by @code{nscd-service}. It uses the caches defined by
13366 @code{%nscd-default-caches}; see below.
13369 @deftp {Data Type} nscd-configuration
13370 This is the data type representing the name service cache daemon (nscd)
13375 @item @code{name-services} (default: @code{'()})
13376 List of packages denoting @dfn{name services} that must be visible to
13377 the nscd---e.g., @code{(list @var{nss-mdns})}.
13379 @item @code{glibc} (default: @var{glibc})
13380 Package object denoting the GNU C Library providing the @command{nscd}
13383 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
13384 Name of the nscd log file. This is where debugging output goes when
13385 @code{debug-level} is strictly positive.
13387 @item @code{debug-level} (default: @code{0})
13388 Integer denoting the debugging levels. Higher numbers mean that more
13389 debugging output is logged.
13391 @item @code{caches} (default: @code{%nscd-default-caches})
13392 List of @code{<nscd-cache>} objects denoting things to be cached; see
13398 @deftp {Data Type} nscd-cache
13399 Data type representing a cache database of nscd and its parameters.
13403 @item @code{database}
13404 This is a symbol representing the name of the database to be cached.
13405 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
13406 @code{services}, which designate the corresponding NSS database
13407 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
13409 @item @code{positive-time-to-live}
13410 @itemx @code{negative-time-to-live} (default: @code{20})
13411 A number representing the number of seconds during which a positive or
13412 negative lookup result remains in cache.
13414 @item @code{check-files?} (default: @code{#t})
13415 Whether to check for updates of the files corresponding to
13418 For instance, when @var{database} is @code{hosts}, setting this flag
13419 instructs nscd to check for updates in @file{/etc/hosts} and to take
13422 @item @code{persistent?} (default: @code{#t})
13423 Whether the cache should be stored persistently on disk.
13425 @item @code{shared?} (default: @code{#t})
13426 Whether the cache should be shared among users.
13428 @item @code{max-database-size} (default: 32@tie{}MiB)
13429 Maximum size in bytes of the database cache.
13431 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
13432 @c settings, so leave them out.
13437 @defvr {Scheme Variable} %nscd-default-caches
13438 List of @code{<nscd-cache>} objects used by default by
13439 @code{nscd-configuration} (see above).
13441 It enables persistent and aggressive caching of service and host name
13442 lookups. The latter provides better host name lookup performance,
13443 resilience in the face of unreliable name servers, and also better
13444 privacy---often the result of host name lookups is in local cache, so
13445 external name servers do not even need to be queried.
13448 @anchor{syslog-configuration-type}
13451 @deftp {Data Type} syslog-configuration
13452 This data type represents the configuration of the syslog daemon.
13455 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
13456 The syslog daemon to use.
13458 @item @code{config-file} (default: @code{%default-syslog.conf})
13459 The syslog configuration file to use.
13464 @anchor{syslog-service}
13466 @deffn {Scheme Procedure} syslog-service @var{config}
13467 Return a service that runs a syslog daemon according to @var{config}.
13469 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
13470 information on the configuration file syntax.
13473 @defvr {Scheme Variable} guix-service-type
13474 This is the type of the service that runs the build daemon,
13475 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
13476 @code{guix-configuration} record as described below.
13479 @anchor{guix-configuration-type}
13480 @deftp {Data Type} guix-configuration
13481 This data type represents the configuration of the Guix build daemon.
13482 @xref{Invoking guix-daemon}, for more information.
13485 @item @code{guix} (default: @var{guix})
13486 The Guix package to use.
13488 @item @code{build-group} (default: @code{"guixbuild"})
13489 Name of the group for build user accounts.
13491 @item @code{build-accounts} (default: @code{10})
13492 Number of build user accounts to create.
13494 @item @code{authorize-key?} (default: @code{#t})
13495 @cindex substitutes, authorization thereof
13496 Whether to authorize the substitute keys listed in
13497 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
13498 (@pxref{Substitutes}).
13500 @vindex %default-authorized-guix-keys
13501 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
13502 The list of authorized key files for archive imports, as a list of
13503 string-valued gexps (@pxref{Invoking guix archive}). By default, it
13504 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
13506 @item @code{use-substitutes?} (default: @code{#t})
13507 Whether to use substitutes.
13509 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
13510 The list of URLs where to look for substitutes by default.
13512 @item @code{max-silent-time} (default: @code{0})
13513 @itemx @code{timeout} (default: @code{0})
13514 The number of seconds of silence and the number of seconds of activity,
13515 respectively, after which a build process times out. A value of zero
13516 disables the timeout.
13518 @item @code{log-compression} (default: @code{'bzip2})
13519 The type of compression used for build logs---one of @code{gzip},
13520 @code{bzip2}, or @code{none}.
13522 @item @code{extra-options} (default: @code{'()})
13523 List of extra command-line options for @command{guix-daemon}.
13525 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
13526 File where @command{guix-daemon}'s standard output and standard error
13529 @cindex HTTP proxy, for @code{guix-daemon}
13530 @cindex proxy, for @code{guix-daemon} HTTP access
13531 @item @code{http-proxy} (default: @code{#f})
13532 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
13533 derivations and substitutes.
13535 It is also possible to change the daemon's proxy at run time through the
13536 @code{set-http-proxy} action, which restarts it:
13539 herd set-http-proxy guix-daemon http://localhost:8118
13542 To clear the proxy settings, run:
13545 herd set-http-proxy guix-daemon
13548 @item @code{tmpdir} (default: @code{#f})
13549 A directory path where the @command{guix-daemon} will perform builds.
13554 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
13555 Run @var{udev}, which populates the @file{/dev} directory dynamically.
13556 udev rules can be provided as a list of files through the @var{rules}
13557 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
13558 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
13559 creation of such rule files.
13561 The @command{herd rules udev} command, as root, returns the name of the
13562 directory containing all the active udev rules.
13565 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
13566 Return a udev-rule file named @var{file-name} containing the rules
13567 defined by the @var{contents} literal.
13569 In the following example, a rule for a USB device is defined to be
13570 stored in the file @file{90-usb-thing.rules}. The rule runs a script
13571 upon detecting a USB device with a given product identifier.
13574 (define %example-udev-rule
13576 "90-usb-thing.rules"
13577 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
13578 "ATTR@{product@}==\"Example\", "
13579 "RUN+=\"/path/to/script\"")))
13583 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
13584 [#:groups @var{groups}]
13585 Return a service that extends @code{udev-service-type } with @var{rules}
13586 and @code{account-service-type} with @var{groups} as system groups.
13587 This works by creating a singleton service type
13588 @code{@var{name}-udev-rules}, of which the returned service is an
13591 Here we show how it can be used to extend @code{udev-service-type} with the
13592 previously defined rule @code{%example-udev-rule}.
13598 (cons (udev-rules-service 'usb-thing %example-udev-rule)
13599 %desktop-services)))
13603 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
13604 Return a udev file named @var{file-name} containing the rules defined
13605 within @var{file}, a file-like object.
13607 The following example showcases how we can use an existing rule file.
13610 (use-modules (guix download) ;for url-fetch
13611 (guix packages) ;for origin
13614 (define %android-udev-rules
13616 "51-android-udev.rules"
13617 (let ((version "20170910"))
13620 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
13621 "android-udev-rules/" version "/51-android.rules"))
13623 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
13627 Additionally, Guix package definitions can be included in @var{rules} in
13628 order to extend the udev rules with the definitions found under their
13629 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
13630 @var{file->udev-rule} example, we could have used the
13631 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
13632 packages android)} module.
13634 The following example shows how to use the @var{android-udev-rules}
13635 package so that the Android tool @command{adb} can detect devices
13636 without root privileges. It also details how to create the
13637 @code{adbusers} group, which is required for the proper functioning of
13638 the rules defined within the @code{android-udev-rules} package. To
13639 create such a group, we must define it both as part of the
13640 @code{supplementary-groups} of our @code{user-account} declaration, as
13641 well as in the @var{groups} of the @code{udev-rules-service} procedure.
13644 (use-modules (gnu packages android) ;for android-udev-rules
13645 (gnu system shadow) ;for user-group
13650 (users (cons (user-account
13652 (supplementary-groups
13653 '("adbusers" ;for adb
13654 "wheel" "netdev" "audio" "video")))))
13657 (cons (udev-rules-service 'android android-udev-rules
13658 #:groups '("adbusers"))
13659 %desktop-services)))
13662 @defvr {Scheme Variable} urandom-seed-service-type
13663 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
13664 when rebooting. It also tries to seed @file{/dev/urandom} from
13665 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
13669 @defvr {Scheme Variable} %random-seed-file
13670 This is the name of the file where some random bytes are saved by
13671 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
13672 It defaults to @file{/var/lib/random-seed}.
13677 @defvr {Scheme Variable} gpm-service-type
13678 This is the type of the service that runs GPM, the @dfn{general-purpose
13679 mouse daemon}, which provides mouse support to the Linux console. GPM
13680 allows users to use the mouse in the console, notably to select, copy,
13683 The value for services of this type must be a @code{gpm-configuration}
13684 (see below). This service is not part of @code{%base-services}.
13687 @deftp {Data Type} gpm-configuration
13688 Data type representing the configuration of GPM.
13691 @item @code{options} (default: @code{%default-gpm-options})
13692 Command-line options passed to @command{gpm}. The default set of
13693 options instruct @command{gpm} to listen to mouse events on
13694 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
13697 @item @code{gpm} (default: @code{gpm})
13698 The GPM package to use.
13703 @anchor{guix-publish-service-type}
13704 @deffn {Scheme Variable} guix-publish-service-type
13705 This is the service type for @command{guix publish} (@pxref{Invoking
13706 guix publish}). Its value must be a @code{guix-publish-configuration}
13707 object, as described below.
13709 This assumes that @file{/etc/guix} already contains a signing key pair as
13710 created by @command{guix archive --generate-key} (@pxref{Invoking guix
13711 archive}). If that is not the case, the service will fail to start.
13714 @deftp {Data Type} guix-publish-configuration
13715 Data type representing the configuration of the @code{guix publish}
13719 @item @code{guix} (default: @code{guix})
13720 The Guix package to use.
13722 @item @code{port} (default: @code{80})
13723 The TCP port to listen for connections.
13725 @item @code{host} (default: @code{"localhost"})
13726 The host (and thus, network interface) to listen to. Use
13727 @code{"0.0.0.0"} to listen on all the network interfaces.
13729 @item @code{compression} (default: @code{'(("gzip" 3))})
13730 This is a list of compression method/level tuple used when compressing
13731 substitutes. For example, to compress all substitutes with @emph{both} lzip
13732 at level 7 and gzip at level 9, write:
13735 '(("lzip" 7) ("gzip" 9))
13738 Level 9 achieves the best compression ratio at the expense of increased CPU
13739 usage, whereas level 1 achieves fast compression.
13741 An empty list disables compression altogether.
13743 @item @code{nar-path} (default: @code{"nar"})
13744 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
13745 publish, @option{--nar-path}}, for details.
13747 @item @code{cache} (default: @code{#f})
13748 When it is @code{#f}, disable caching and instead generate archives on
13749 demand. Otherwise, this should be the name of a directory---e.g.,
13750 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
13751 archives and meta-data ready to be sent. @xref{Invoking guix publish,
13752 @option{--cache}}, for more information on the tradeoffs involved.
13754 @item @code{workers} (default: @code{#f})
13755 When it is an integer, this is the number of worker threads used for
13756 caching; when @code{#f}, the number of processors is used.
13757 @xref{Invoking guix publish, @option{--workers}}, for more information.
13759 @item @code{ttl} (default: @code{#f})
13760 When it is an integer, this denotes the @dfn{time-to-live} in seconds
13761 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
13762 for more information.
13766 @anchor{rngd-service}
13767 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
13768 [#:device "/dev/hwrng"]
13769 Return a service that runs the @command{rngd} program from @var{rng-tools}
13770 to add @var{device} to the kernel's entropy pool. The service will fail if
13771 @var{device} does not exist.
13774 @anchor{pam-limits-service}
13775 @cindex session limits
13780 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
13782 Return a service that installs a configuration file for the
13783 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
13784 @code{pam_limits} module}. The procedure optionally takes a list of
13785 @code{pam-limits-entry} values, which can be used to specify
13786 @code{ulimit} limits and nice priority limits to user sessions.
13788 The following limits definition sets two hard and soft limits for all
13789 login sessions of users in the @code{realtime} group:
13792 (pam-limits-service
13794 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
13795 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
13798 The first entry increases the maximum realtime priority for
13799 non-privileged processes; the second entry lifts any restriction of the
13800 maximum address space that can be locked in memory. These settings are
13801 commonly used for real-time audio systems.
13804 @node Scheduled Job Execution
13805 @subsection Scheduled Job Execution
13809 @cindex scheduling jobs
13810 The @code{(gnu services mcron)} module provides an interface to
13811 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
13812 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
13813 Unix @command{cron} daemon; the main difference is that it is
13814 implemented in Guile Scheme, which provides a lot of flexibility when
13815 specifying the scheduling of jobs and their actions.
13817 The example below defines an operating system that runs the
13818 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
13819 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
13820 well as the @command{mkid} command on behalf of an unprivileged user
13821 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
13822 gexps to introduce job definitions that are passed to mcron
13823 (@pxref{G-Expressions}).
13826 (use-modules (guix) (gnu) (gnu services mcron))
13827 (use-package-modules base idutils)
13829 (define updatedb-job
13830 ;; Run 'updatedb' at 3AM every day. Here we write the
13831 ;; job's action as a Scheme procedure.
13832 #~(job '(next-hour '(3))
13834 (execl (string-append #$findutils "/bin/updatedb")
13836 "--prunepaths=/tmp /var/tmp /gnu/store"))))
13838 (define garbage-collector-job
13839 ;; Collect garbage 5 minutes after midnight every day.
13840 ;; The job's action is a shell command.
13841 #~(job "5 0 * * *" ;Vixie cron syntax
13844 (define idutils-job
13845 ;; Update the index database as user "charlie" at 12:15PM
13846 ;; and 19:15PM. This runs from the user's home directory.
13847 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
13848 (string-append #$idutils "/bin/mkid src")
13853 (services (cons (service mcron-service-type
13854 (mcron-configuration
13855 (jobs (list garbage-collector-job
13861 For more complex jobs defined in Scheme where you need control over the top
13862 level, for instance to introduce a @code{use-modules} form, you can move your
13863 code to a separate program using the @code{program-file} procedure of the
13864 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
13868 (define %battery-alert-job
13869 ;; Beep when the battery percentage falls below %MIN-LEVEL.
13871 '(next-minute (range 0 60 1))
13873 "battery-alert.scm"
13874 (with-imported-modules (source-module-closure
13875 '((guix build utils)))
13877 (use-modules (guix build utils)
13880 (ice-9 textual-ports)
13883 (define %min-level 20)
13885 (setenv "LC_ALL" "C") ;ensure English output
13886 (and-let* ((input-pipe (open-pipe*
13888 #$(file-append acpi "/bin/acpi")))
13889 (output (get-string-all input-pipe))
13890 (m (string-match "Discharging, ([0-9]+)%" output))
13891 (level (string->number (match:substring m 1)))
13892 ((< level %min-level)))
13893 (format #t "warning: Battery level is low (~a%)~%" level)
13894 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
13897 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
13898 for more information on mcron job specifications. Below is the
13899 reference of the mcron service.
13901 On a running system, you can use the @code{schedule} action of the service to
13902 visualize the mcron jobs that will be executed next:
13905 # herd schedule mcron
13909 The example above lists the next five tasks that will be executed, but you can
13910 also specify the number of tasks to display:
13913 # herd schedule mcron 10
13916 @defvr {Scheme Variable} mcron-service-type
13917 This is the type of the @code{mcron} service, whose value is an
13918 @code{mcron-configuration} object.
13920 This service type can be the target of a service extension that provides
13921 it additional job specifications (@pxref{Service Composition}). In
13922 other words, it is possible to define services that provide additional
13926 @deftp {Data Type} mcron-configuration
13927 Data type representing the configuration of mcron.
13930 @item @code{mcron} (default: @var{mcron})
13931 The mcron package to use.
13934 This is a list of gexps (@pxref{G-Expressions}), where each gexp
13935 corresponds to an mcron job specification (@pxref{Syntax, mcron job
13936 specifications,, mcron, GNU@tie{}mcron}).
13942 @subsection Log Rotation
13945 @cindex log rotation
13947 Log files such as those found in @file{/var/log} tend to grow endlessly,
13948 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
13949 their contents in separate files, possibly compressed. The @code{(gnu
13950 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
13951 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
13953 This service is part of @code{%base-services}, and thus enabled by
13954 default, with the default settings, for commonly encountered log files.
13955 The example below shows how to extend it with an additional
13956 @dfn{rotation}, should you need to do that (usually, services that
13957 produce log files already take care of that):
13960 (use-modules (guix) (gnu))
13961 (use-service-modules admin)
13963 (define my-log-files
13964 ;; Log files that I want to rotate.
13965 '("/var/log/something.log" "/var/log/another.log"))
13969 (services (cons (simple-service 'rotate-my-stuff
13970 rottlog-service-type
13971 (list (log-rotation
13973 (files my-log-files))))
13977 @defvr {Scheme Variable} rottlog-service-type
13978 This is the type of the Rottlog service, whose value is a
13979 @code{rottlog-configuration} object.
13981 Other services can extend this one with new @code{log-rotation} objects
13982 (see below), thereby augmenting the set of files to be rotated.
13984 This service type can define mcron jobs (@pxref{Scheduled Job
13985 Execution}) to run the rottlog service.
13988 @deftp {Data Type} rottlog-configuration
13989 Data type representing the configuration of rottlog.
13992 @item @code{rottlog} (default: @code{rottlog})
13993 The Rottlog package to use.
13995 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
13996 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
13997 rottlog, GNU Rot[t]log Manual}).
13999 @item @code{rotations} (default: @code{%default-rotations})
14000 A list of @code{log-rotation} objects as defined below.
14003 This is a list of gexps where each gexp corresponds to an mcron job
14004 specification (@pxref{Scheduled Job Execution}).
14008 @deftp {Data Type} log-rotation
14009 Data type representing the rotation of a group of log files.
14011 Taking an example from the Rottlog manual (@pxref{Period Related File
14012 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
14018 (files '("/var/log/apache/*"))
14019 (options '("storedir apache-archives"
14025 The list of fields is as follows:
14028 @item @code{frequency} (default: @code{'weekly})
14029 The log rotation frequency, a symbol.
14032 The list of files or file glob patterns to rotate.
14034 @item @code{options} (default: @code{'()})
14035 The list of rottlog options for this rotation (@pxref{Configuration
14036 parameters,,, rottlog, GNU Rot[t]lg Manual}).
14038 @item @code{post-rotate} (default: @code{#f})
14039 Either @code{#f} or a gexp to execute once the rotation has completed.
14043 @defvr {Scheme Variable} %default-rotations
14044 Specifies weekly rotation of @code{%rotated-files} and of
14045 @file{/var/log/guix-daemon.log}.
14048 @defvr {Scheme Variable} %rotated-files
14049 The list of syslog-controlled files to be rotated. By default it is:
14050 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
14051 "/var/log/maillog")}.
14054 @node Networking Services
14055 @subsection Networking Services
14057 The @code{(gnu services networking)} module provides services to configure
14058 the network interface.
14060 @cindex DHCP, networking service
14061 @defvr {Scheme Variable} dhcp-client-service-type
14062 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
14063 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
14064 is the DHCP client package to use, @code{isc-dhcp} by default.
14067 @deffn {Scheme Procedure} dhcpd-service-type
14068 This type defines a service that runs a DHCP daemon. To create a
14069 service of this type, you must supply a @code{<dhcpd-configuration>}.
14073 (service dhcpd-service-type
14074 (dhcpd-configuration
14075 (config-file (local-file "my-dhcpd.conf"))
14076 (interfaces '("enp0s25"))))
14080 @deftp {Data Type} dhcpd-configuration
14082 @item @code{package} (default: @code{isc-dhcp})
14083 The package that provides the DHCP daemon. This package is expected to
14084 provide the daemon at @file{sbin/dhcpd} relative to its output
14085 directory. The default package is the
14086 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
14087 @item @code{config-file} (default: @code{#f})
14088 The configuration file to use. This is required. It will be passed to
14089 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
14090 object (@pxref{G-Expressions, file-like objects}). See @code{man
14091 dhcpd.conf} for details on the configuration file syntax.
14092 @item @code{version} (default: @code{"4"})
14093 The DHCP version to use. The ISC DHCP server supports the values ``4'',
14094 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
14095 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
14097 @item @code{run-directory} (default: @code{"/run/dhcpd"})
14098 The run directory to use. At service activation time, this directory
14099 will be created if it does not exist.
14100 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
14101 The PID file to use. This corresponds to the @code{-pf} option of
14102 @code{dhcpd}. See @code{man dhcpd} for details.
14103 @item @code{interfaces} (default: @code{'()})
14104 The names of the network interfaces on which dhcpd should listen for
14105 broadcasts. If this list is not empty, then its elements (which must be
14106 strings) will be appended to the @code{dhcpd} invocation when starting
14107 the daemon. It may not be necessary to explicitly specify any
14108 interfaces here; see @code{man dhcpd} for details.
14112 @defvr {Scheme Variable} static-networking-service-type
14113 This is the type for statically-configured network interfaces.
14114 @c TODO Document <static-networking> data structures.
14117 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
14118 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
14119 [#:requirement @code{'(udev)}]
14120 Return a service that starts @var{interface} with address @var{ip}. If
14121 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
14122 it must be a string specifying the default network gateway. @var{requirement}
14123 can be used to declare a dependency on another service before configuring the
14126 This procedure can be called several times, one for each network
14127 interface of interest. Behind the scenes what it does is extend
14128 @code{static-networking-service-type} with additional network interfaces
14134 (static-networking-service "eno1" "192.168.1.82"
14135 #:gateway "192.168.1.2"
14136 #:name-servers '("192.168.1.2"))
14143 @cindex network management
14144 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
14145 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
14146 management daemon that aims to simplify wired and wireless networking.
14148 This service adds the @var{wicd} package to the global profile, providing
14149 several commands to interact with the daemon and configure networking:
14150 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
14151 and @command{wicd-curses} user interfaces.
14154 @cindex ModemManager
14156 @defvr {Scheme Variable} modem-manager-service-type
14157 This is the service type for the
14158 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
14159 service. The value for this service type is a
14160 @code{modem-manager-configuration} record.
14162 This service is part of @code{%desktop-services} (@pxref{Desktop
14166 @deftp {Data Type} modem-manager-configuration
14167 Data type representing the configuration of ModemManager.
14170 @item @code{modem-manager} (default: @code{modem-manager})
14171 The ModemManager package to use.
14176 @cindex USB_ModeSwitch
14177 @cindex Modeswitching
14179 @defvr {Scheme Variable} usb-modeswitch-service-type
14180 This is the service type for the
14181 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
14182 value for this service type is a @code{usb-modeswitch-configuration} record.
14184 When plugged in, some USB modems (and other USB devices) initially present
14185 themselves as a read-only storage medium and not as a modem. They need to be
14186 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
14187 installs udev rules to automatically modeswitch these devices when they are
14190 This service is part of @code{%desktop-services} (@pxref{Desktop
14194 @deftp {Data Type} usb-modeswitch-configuration
14195 Data type representing the configuration of USB_ModeSwitch.
14198 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
14199 The USB_ModeSwitch package providing the binaries for modeswitching.
14201 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
14202 The package providing the device data and udev rules file used by
14205 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
14206 Which config file to use for the USB_ModeSwitch dispatcher. By default the
14207 config file shipped with USB_ModeSwitch is used which disables logging to
14208 @file{/var/log} among other default settings. If set to @code{#f}, no config
14214 @cindex NetworkManager
14216 @defvr {Scheme Variable} network-manager-service-type
14217 This is the service type for the
14218 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
14219 service. The value for this service type is a
14220 @code{network-manager-configuration} record.
14222 This service is part of @code{%desktop-services} (@pxref{Desktop
14226 @deftp {Data Type} network-manager-configuration
14227 Data type representing the configuration of NetworkManager.
14230 @item @code{network-manager} (default: @code{network-manager})
14231 The NetworkManager package to use.
14233 @item @code{dns} (default: @code{"default"})
14234 Processing mode for DNS, which affects how NetworkManager uses the
14235 @code{resolv.conf} configuration file.
14239 NetworkManager will update @code{resolv.conf} to reflect the nameservers
14240 provided by currently active connections.
14243 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
14244 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
14245 then update @code{resolv.conf} to point to the local nameserver.
14247 With this setting, you can share your network connection. For example when
14248 you want to share your network connection to another laptop @i{via} an
14249 Ethernet cable, you can open @command{nm-connection-editor} and configure the
14250 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
14251 and reestablish the connection (or reboot).
14253 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
14254 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
14255 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
14256 browser on your host system, or connect to the VM @i{via} SSH
14257 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
14258 host-to-guest connection, run this command once:
14261 nmcli connection add type tun \
14262 connection.interface-name tap0 \
14263 tun.mode tap tun.owner $(id -u) \
14264 ipv4.method shared \
14265 ipv4.addresses 172.28.112.1/24
14268 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
14269 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
14270 @command{qemu-system-...}.
14273 NetworkManager will not modify @code{resolv.conf}.
14276 @item @code{vpn-plugins} (default: @code{'()})
14277 This is the list of available plugins for virtual private networks
14278 (VPNs). An example of this is the @code{network-manager-openvpn}
14279 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
14285 @deffn {Scheme Variable} connman-service-type
14286 This is the service type to run @url{https://01.org/connman,Connman},
14287 a network connection manager.
14289 Its value must be an
14290 @code{connman-configuration} record as in this example:
14293 (service connman-service-type
14294 (connman-configuration
14295 (disable-vpn? #t)))
14298 See below for details about @code{connman-configuration}.
14301 @deftp {Data Type} connman-configuration
14302 Data Type representing the configuration of connman.
14305 @item @code{connman} (default: @var{connman})
14306 The connman package to use.
14308 @item @code{disable-vpn?} (default: @code{#f})
14309 When true, disable connman's vpn plugin.
14313 @cindex WPA Supplicant
14314 @defvr {Scheme Variable} wpa-supplicant-service-type
14315 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
14316 supplicant}, an authentication daemon required to authenticate against
14317 encrypted WiFi or ethernet networks.
14320 @deftp {Data Type} wpa-supplicant-configuration
14321 Data type representing the configuration of WPA Supplicant.
14323 It takes the following parameters:
14326 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
14327 The WPA Supplicant package to use.
14329 @item @code{requirement} (default: @code{'(user-processes dbus-system loopback syslogd)}
14330 List of services that should be started before WPA Supplicant starts.
14332 @item @code{dbus?} (default: @code{#t})
14333 Whether to listen for requests on D-Bus.
14335 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
14336 Where to store the PID file.
14338 @item @code{interface} (default: @code{#f})
14339 If this is set, it must specify the name of a network interface that
14340 WPA supplicant will control.
14342 @item @code{config-file} (default: @code{#f})
14343 Optional configuration file to use.
14345 @item @code{extra-options} (default: @code{'()})
14346 List of additional command-line arguments to pass to the daemon.
14350 @cindex hostapd service, for Wi-Fi access points
14351 @cindex Wi-Fi access points, hostapd service
14352 @defvr {Scheme Variable} hostapd-service-type
14353 This is the service type to run the @uref{https://w1.fi/hostapd/,
14354 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
14355 authentication servers. Its associated value must be a
14356 @code{hostapd-configuration} as shown below:
14359 ;; Use wlan1 to run the access point for "My Network".
14360 (service hostapd-service-type
14361 (hostapd-configuration
14362 (interface "wlan1")
14363 (ssid "My Network")
14368 @deftp {Data Type} hostapd-configuration
14369 This data type represents the configuration of the hostapd service, with
14370 the following fields:
14373 @item @code{package} (default: @code{hostapd})
14374 The hostapd package to use.
14376 @item @code{interface} (default: @code{"wlan0"})
14377 The network interface to run the WiFi access point.
14380 The SSID (@dfn{service set identifier}), a string that identifies this
14383 @item @code{broadcast-ssid?} (default: @code{#t})
14384 Whether to broadcast this SSID.
14386 @item @code{channel} (default: @code{1})
14387 The WiFi channel to use.
14389 @item @code{driver} (default: @code{"nl80211"})
14390 The driver interface type. @code{"nl80211"} is used with all Linux
14391 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
14392 RADIUS server that does # not control any wireless/wired driver.
14394 @item @code{extra-settings} (default: @code{""})
14395 Extra settings to append as-is to the hostapd configuration file. See
14396 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
14397 configuration file reference.
14401 @defvr {Scheme Variable} simulated-wifi-service-type
14402 This is the type of a service to simulate WiFi networking, which can be
14403 useful in virtual machines for testing purposes. The service loads the
14405 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
14406 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
14407 network that can be seen on @code{wlan0}, by default.
14409 The service's value is a @code{hostapd-configuration} record.
14413 @defvr {Scheme Variable} iptables-service-type
14414 This is the service type to set up an iptables configuration. iptables is a
14415 packet filtering framework supported by the Linux kernel. This service
14416 supports configuring iptables for both IPv4 and IPv6. A simple example
14417 configuration rejecting all incoming connections except those to the ssh port
14421 (service iptables-service-type
14422 (iptables-configuration
14423 (ipv4-rules (plain-file "iptables.rules" "*filter
14427 -A INPUT -p tcp --dport 22 -j ACCEPT
14428 -A INPUT -j REJECT --reject-with icmp-port-unreachable
14431 (ipv6-rules (plain-file "ip6tables.rules" "*filter
14435 -A INPUT -p tcp --dport 22 -j ACCEPT
14436 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
14442 @deftp {Data Type} iptables-configuration
14443 The data type representing the configuration of iptables.
14446 @item @code{iptables} (default: @code{iptables})
14447 The iptables package that provides @code{iptables-restore} and
14448 @code{ip6tables-restore}.
14449 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
14450 The iptables rules to use. It will be passed to @code{iptables-restore}.
14451 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
14453 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
14454 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
14455 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
14461 @defvr {Scheme Variable} nftables-service-type
14462 This is the service type to set up a nftables configuration. nftables is a
14463 netfilter project that aims to replace the existing iptables, ip6tables,
14464 arptables and ebtables framework. It provides a new packet filtering
14465 framework, a new user-space utility @command{nft}, and a compatibility layer
14466 for iptables. This service comes with a default ruleset
14467 @code{%default-nftables-ruleset} that rejecting all incomming connections
14468 except those to the ssh port 22. To use it, simply write:
14471 (service nftables-service-type)
14475 @deftp {Data Type} nftables-configuration
14476 The data type representing the configuration of nftables.
14479 @item @code{package} (default: @code{nftables})
14480 The nftables package that provides @command{nft}.
14481 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
14482 The nftables ruleset to use. This may be any ``file-like'' object
14483 (@pxref{G-Expressions, file-like objects}).
14487 @cindex NTP (Network Time Protocol), service
14488 @cindex ntpd, service for the Network Time Protocol daemon
14489 @cindex real time clock
14490 @defvr {Scheme Variable} ntp-service-type
14491 This is the type of the service running the @uref{https://www.ntp.org,
14492 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
14493 system clock synchronized with that of the specified NTP servers.
14495 The value of this service is an @code{ntpd-configuration} object, as described
14499 @deftp {Data Type} ntp-configuration
14500 This is the data type for the NTP service configuration.
14503 @item @code{servers} (default: @code{%ntp-servers})
14504 This is the list of servers (@code{<ntp-server>} records) with which
14505 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
14508 @item @code{allow-large-adjustment?} (default: @code{#t})
14509 This determines whether @command{ntpd} is allowed to make an initial
14510 adjustment of more than 1,000 seconds.
14512 @item @code{ntp} (default: @code{ntp})
14513 The NTP package to use.
14517 @defvr {Scheme Variable} %ntp-servers
14518 List of host names used as the default NTP servers. These are servers of the
14519 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
14522 @deftp {Data Type} ntp-server
14523 The data type representing the configuration of a NTP server.
14526 @item @code{type} (default: @code{'server})
14527 The type of the NTP server, given as a symbol. One of @code{'pool},
14528 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
14530 @item @code{address}
14531 The address of the server, as a string.
14533 @item @code{options}
14534 NTPD options to use with that specific server, given as a list of option names
14535 and/or of option names and values tuples. The following example define a server
14536 to use with the options @option{iburst} and @option{prefer}, as well as
14537 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
14542 (address "some.ntp.server.org")
14543 (options `(iburst (version 3) (maxpoll 16) prefer))))
14549 @deffn {Scheme Procedure} openntpd-service-type
14550 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
14551 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
14552 clock synchronized with that of the given servers.
14556 openntpd-service-type
14557 (openntpd-configuration
14558 (listen-on '("127.0.0.1" "::1"))
14559 (sensor '("udcf0 correction 70000"))
14560 (constraint-from '("www.gnu.org"))
14561 (constraints-from '("https://www.google.com/"))
14562 (allow-large-adjustment? #t)))
14567 @defvr {Scheme Variable} %openntpd-servers
14568 This variable is a list of the server addresses defined in
14569 @code{%ntp-servers}.
14572 @deftp {Data Type} openntpd-configuration
14574 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
14575 The openntpd executable to use.
14576 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
14577 A list of local IP addresses or hostnames the ntpd daemon should listen on.
14578 @item @code{query-from} (default: @code{'()})
14579 A list of local IP address the ntpd daemon should use for outgoing queries.
14580 @item @code{sensor} (default: @code{'()})
14581 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
14582 will listen to each sensor that actually exists and ignore non-existent ones.
14583 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
14585 @item @code{server} (default: @code{'()})
14586 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
14587 @item @code{servers} (default: @code{%openntp-servers})
14588 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
14589 @item @code{constraint-from} (default: @code{'()})
14590 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
14591 This time information is not used for precision but acts as an authenticated
14592 constraint, thereby reducing the impact of unauthenticated NTP
14593 man-in-the-middle attacks.
14594 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
14596 @item @code{constraints-from} (default: @code{'()})
14597 As with constraint from, specify a list of URLs, IP addresses or hostnames of
14598 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
14599 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
14600 @item @code{allow-large-adjustment?} (default: @code{#f})
14601 Determines if @code{ntpd} is allowed to make an initial adjustment of more
14607 @deffn {Scheme variable} inetd-service-type
14608 This service runs the @command{inetd} (@pxref{inetd invocation,,,
14609 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
14610 connections on internet sockets, and lazily starts the specified server
14611 program when a connection is made on one of these sockets.
14613 The value of this service is an @code{inetd-configuration} object. The
14614 following example configures the @command{inetd} daemon to provide the
14615 built-in @command{echo} service, as well as an smtp service which
14616 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
14617 gateway @code{hostname}:
14622 (inetd-configuration
14626 (socket-type 'stream)
14633 (socket-type 'stream)
14637 (program (file-append openssh "/bin/ssh"))
14639 '("ssh" "-qT" "-i" "/path/to/ssh_key"
14640 "-W" "smtp-server:25" "user@@hostname")))))))
14643 See below for more details about @code{inetd-configuration}.
14646 @deftp {Data Type} inetd-configuration
14647 Data type representing the configuration of @command{inetd}.
14650 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
14651 The @command{inetd} executable to use.
14653 @item @code{entries} (default: @code{'()})
14654 A list of @command{inetd} service entries. Each entry should be created
14655 by the @code{inetd-entry} constructor.
14659 @deftp {Data Type} inetd-entry
14660 Data type representing an entry in the @command{inetd} configuration.
14661 Each entry corresponds to a socket where @command{inetd} will listen for
14665 @item @code{node} (default: @code{#f})
14666 Optional string, a comma-separated list of local addresses
14667 @command{inetd} should use when listening for this service.
14668 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
14669 description of all options.
14671 A string, the name must correspond to an entry in @code{/etc/services}.
14672 @item @code{socket-type}
14673 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
14675 @item @code{protocol}
14676 A string, must correspond to an entry in @code{/etc/protocols}.
14677 @item @code{wait?} (default: @code{#t})
14678 Whether @command{inetd} should wait for the server to exit before
14679 listening to new service requests.
14681 A string containing the user (and, optionally, group) name of the user
14682 as whom the server should run. The group name can be specified in a
14683 suffix, separated by a colon or period, i.e.@: @code{"user"},
14684 @code{"user:group"} or @code{"user.group"}.
14685 @item @code{program} (default: @code{"internal"})
14686 The server program which will serve the requests, or @code{"internal"}
14687 if @command{inetd} should use a built-in service.
14688 @item @code{arguments} (default: @code{'()})
14689 A list strings or file-like objects, which are the server program's
14690 arguments, starting with the zeroth argument, i.e.@: the name of the
14691 program itself. For @command{inetd}'s internal services, this entry
14692 must be @code{'()} or @code{'("internal")}.
14695 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
14696 detailed discussion of each configuration field.
14700 @defvr {Scheme Variable} tor-service-type
14701 This is the type for a service that runs the @uref{https://torproject.org,
14702 Tor} anonymous networking daemon. The service is configured using a
14703 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
14704 @code{tor} unprivileged user, which is a member of the @code{tor} group.
14708 @deftp {Data Type} tor-configuration
14710 @item @code{tor} (default: @code{tor})
14711 The package that provides the Tor daemon. This package is expected to provide
14712 the daemon at @file{bin/tor} relative to its output directory. The default
14713 package is the @uref{https://www.torproject.org, Tor Project's}
14716 @item @code{config-file} (default: @code{(plain-file "empty" "")})
14717 The configuration file to use. It will be appended to a default configuration
14718 file, and the final configuration file will be passed to @code{tor} via its
14719 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
14720 file-like objects}). See @code{man tor} for details on the configuration file
14723 @item @code{hidden-services} (default: @code{'()})
14724 The list of @code{<hidden-service>} records to use. For any hidden service
14725 you include in this list, appropriate configuration to enable the hidden
14726 service will be automatically added to the default configuration file. You
14727 may conveniently create @code{<hidden-service>} records using the
14728 @code{tor-hidden-service} procedure described below.
14730 @item @code{socks-socket-type} (default: @code{'tcp})
14731 The default socket type that Tor should use for its SOCKS socket. This must
14732 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
14733 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
14734 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
14735 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
14738 If you want to customize the SOCKS socket in more detail, leave
14739 @code{socks-socket-type} at its default value of @code{'tcp} and use
14740 @code{config-file} to override the default by providing your own
14741 @code{SocksPort} option.
14745 @cindex hidden service
14746 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
14747 Define a new Tor @dfn{hidden service} called @var{name} and implementing
14748 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
14751 '((22 "127.0.0.1:22")
14752 (80 "127.0.0.1:8080"))
14755 In this example, port 22 of the hidden service is mapped to local port 22, and
14756 port 80 is mapped to local port 8080.
14758 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
14759 the @file{hostname} file contains the @code{.onion} host name for the hidden
14762 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
14763 project's documentation} for more information.
14766 The @code{(gnu services rsync)} module provides the following services:
14768 You might want an rsync daemon if you have files that you want available
14769 so anyone (or just yourself) can download existing files or upload new
14772 @deffn {Scheme Variable} rsync-service-type
14773 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
14774 The value for this service type is a
14775 @command{rsync-configuration} record as in this example:
14778 (service rsync-service-type)
14781 See below for details about @code{rsync-configuration}.
14784 @deftp {Data Type} rsync-configuration
14785 Data type representing the configuration for @code{rsync-service}.
14788 @item @code{package} (default: @var{rsync})
14789 @code{rsync} package to use.
14791 @item @code{port-number} (default: @code{873})
14792 TCP port on which @command{rsync} listens for incoming connections. If port
14793 is less than @code{1024} @command{rsync} needs to be started as the
14794 @code{root} user and group.
14796 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
14797 Name of the file where @command{rsync} writes its PID.
14799 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
14800 Name of the file where @command{rsync} writes its lock file.
14802 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
14803 Name of the file where @command{rsync} writes its log file.
14805 @item @code{use-chroot?} (default: @var{#t})
14806 Whether to use chroot for @command{rsync} shared directory.
14808 @item @code{share-path} (default: @file{/srv/rsync})
14809 Location of the @command{rsync} shared directory.
14811 @item @code{share-comment} (default: @code{"Rsync share"})
14812 Comment of the @command{rsync} shared directory.
14814 @item @code{read-only?} (default: @var{#f})
14815 Read-write permissions to shared directory.
14817 @item @code{timeout} (default: @code{300})
14818 I/O timeout in seconds.
14820 @item @code{user} (default: @var{"root"})
14821 Owner of the @code{rsync} process.
14823 @item @code{group} (default: @var{"root"})
14824 Group of the @code{rsync} process.
14826 @item @code{uid} (default: @var{"rsyncd"})
14827 User name or user ID that file transfers to and from that module should take
14828 place as when the daemon was run as @code{root}.
14830 @item @code{gid} (default: @var{"rsyncd"})
14831 Group name or group ID that will be used when accessing the module.
14836 Furthermore, @code{(gnu services ssh)} provides the following services.
14840 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
14841 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
14842 [#:allow-empty-passwords? #f] [#:root-login? #f] @
14843 [#:syslog-output? #t] [#:x11-forwarding? #t] @
14844 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
14845 [#:public-key-authentication? #t] [#:initialize? #t]
14846 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
14847 @var{host-key} must designate a file containing the host key, and readable
14850 When @var{daemonic?} is true, @command{lshd} will detach from the
14851 controlling terminal and log its output to syslogd, unless one sets
14852 @var{syslog-output?} to false. Obviously, it also makes lsh-service
14853 depend on existence of syslogd service. When @var{pid-file?} is true,
14854 @command{lshd} writes its PID to the file called @var{pid-file}.
14856 When @var{initialize?} is true, automatically create the seed and host key
14857 upon service activation if they do not exist yet. This may take long and
14858 require interaction.
14860 When @var{initialize?} is false, it is up to the user to initialize the
14861 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
14862 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
14863 basics,,, lsh, LSH Manual}).
14865 When @var{interfaces} is empty, lshd listens for connections on all the
14866 network interfaces; otherwise, @var{interfaces} must be a list of host names
14869 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
14870 passwords, and @var{root-login?} specifies whether to accept log-ins as
14873 The other options should be self-descriptive.
14878 @deffn {Scheme Variable} openssh-service-type
14879 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
14880 shell daemon, @command{sshd}. Its value must be an
14881 @code{openssh-configuration} record as in this example:
14884 (service openssh-service-type
14885 (openssh-configuration
14886 (x11-forwarding? #t)
14887 (permit-root-login 'without-password)
14889 `(("alice" ,(local-file "alice.pub"))
14890 ("bob" ,(local-file "bob.pub"))))))
14893 See below for details about @code{openssh-configuration}.
14895 This service can be extended with extra authorized keys, as in this
14899 (service-extension openssh-service-type
14900 (const `(("charlie"
14901 ,(local-file "charlie.pub")))))
14905 @deftp {Data Type} openssh-configuration
14906 This is the configuration record for OpenSSH's @command{sshd}.
14909 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
14910 Name of the file where @command{sshd} writes its PID.
14912 @item @code{port-number} (default: @code{22})
14913 TCP port on which @command{sshd} listens for incoming connections.
14915 @item @code{permit-root-login} (default: @code{#f})
14916 This field determines whether and when to allow logins as root. If
14917 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
14918 If it's the symbol @code{'without-password}, then root logins are
14919 permitted but not with password-based authentication.
14921 @item @code{allow-empty-passwords?} (default: @code{#f})
14922 When true, users with empty passwords may log in. When false, they may
14925 @item @code{password-authentication?} (default: @code{#t})
14926 When true, users may log in with their password. When false, they have
14927 other authentication methods.
14929 @item @code{public-key-authentication?} (default: @code{#t})
14930 When true, users may log in using public key authentication. When
14931 false, users have to use other authentication method.
14933 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
14934 This is used only by protocol version 2.
14936 @item @code{x11-forwarding?} (default: @code{#f})
14937 When true, forwarding of X11 graphical client connections is
14938 enabled---in other words, @command{ssh} options @option{-X} and
14939 @option{-Y} will work.
14941 @item @code{allow-agent-forwarding?} (default: @code{#t})
14942 Whether to allow agent forwarding.
14944 @item @code{allow-tcp-forwarding?} (default: @code{#t})
14945 Whether to allow TCP forwarding.
14947 @item @code{gateway-ports?} (default: @code{#f})
14948 Whether to allow gateway ports.
14950 @item @code{challenge-response-authentication?} (default: @code{#f})
14951 Specifies whether challenge response authentication is allowed (e.g.@: via
14954 @item @code{use-pam?} (default: @code{#t})
14955 Enables the Pluggable Authentication Module interface. If set to
14956 @code{#t}, this will enable PAM authentication using
14957 @code{challenge-response-authentication?} and
14958 @code{password-authentication?}, in addition to PAM account and session
14959 module processing for all authentication types.
14961 Because PAM challenge response authentication usually serves an
14962 equivalent role to password authentication, you should disable either
14963 @code{challenge-response-authentication?} or
14964 @code{password-authentication?}.
14966 @item @code{print-last-log?} (default: @code{#t})
14967 Specifies whether @command{sshd} should print the date and time of the
14968 last user login when a user logs in interactively.
14970 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
14971 Configures external subsystems (e.g.@: file transfer daemon).
14973 This is a list of two-element lists, each of which containing the
14974 subsystem name and a command (with optional arguments) to execute upon
14977 The command @command{internal-sftp} implements an in-process SFTP
14978 server. Alternatively, one can specify the @command{sftp-server} command:
14980 (service openssh-service-type
14981 (openssh-configuration
14983 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
14986 @item @code{accepted-environment} (default: @code{'()})
14987 List of strings describing which environment variables may be exported.
14989 Each string gets on its own line. See the @code{AcceptEnv} option in
14990 @code{man sshd_config}.
14992 This example allows ssh-clients to export the @env{COLORTERM} variable.
14993 It is set by terminal emulators, which support colors. You can use it in
14994 your shell's resource file to enable colors for the prompt and commands
14995 if this variable is set.
14998 (service openssh-service-type
14999 (openssh-configuration
15000 (accepted-environment '("COLORTERM"))))
15003 @item @code{authorized-keys} (default: @code{'()})
15004 @cindex authorized keys, SSH
15005 @cindex SSH authorized keys
15006 This is the list of authorized keys. Each element of the list is a user
15007 name followed by one or more file-like objects that represent SSH public
15011 (openssh-configuration
15013 `(("rekado" ,(local-file "rekado.pub"))
15014 ("chris" ,(local-file "chris.pub"))
15015 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
15019 registers the specified public keys for user accounts @code{rekado},
15020 @code{chris}, and @code{root}.
15022 Additional authorized keys can be specified @i{via}
15023 @code{service-extension}.
15025 Note that this does @emph{not} interfere with the use of
15026 @file{~/.ssh/authorized_keys}.
15028 @item @code{log-level} (default: @code{'info})
15029 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
15030 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
15031 page for @file{sshd_config} for the full list of level names.
15033 @item @code{extra-content} (default: @code{""})
15034 This field can be used to append arbitrary text to the configuration file. It
15035 is especially useful for elaborate configurations that cannot be expressed
15036 otherwise. This configuration, for example, would generally disable root
15037 logins, but permit them from one specific IP address:
15040 (openssh-configuration
15042 Match Address 192.168.0.1
15043 PermitRootLogin yes"))
15049 @deffn {Scheme Procedure} dropbear-service [@var{config}]
15050 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
15051 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
15054 For example, to specify a Dropbear service listening on port 1234, add
15055 this call to the operating system's @code{services} field:
15058 (dropbear-service (dropbear-configuration
15059 (port-number 1234)))
15063 @deftp {Data Type} dropbear-configuration
15064 This data type represents the configuration of a Dropbear SSH daemon.
15067 @item @code{dropbear} (default: @var{dropbear})
15068 The Dropbear package to use.
15070 @item @code{port-number} (default: 22)
15071 The TCP port where the daemon waits for incoming connections.
15073 @item @code{syslog-output?} (default: @code{#t})
15074 Whether to enable syslog output.
15076 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
15077 File name of the daemon's PID file.
15079 @item @code{root-login?} (default: @code{#f})
15080 Whether to allow @code{root} logins.
15082 @item @code{allow-empty-passwords?} (default: @code{#f})
15083 Whether to allow empty passwords.
15085 @item @code{password-authentication?} (default: @code{#t})
15086 Whether to enable password-based authentication.
15091 @deffn {Scheme Variable} autossh-service-type
15092 This is the type for the @uref{https://www.harding.motd.ca/autossh,
15093 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
15094 restarting it as necessary should it die or stop passing traffic.
15095 AutoSSH can be run manually from the command-line by passing arguments
15096 to the binary @command{autossh} from the package @code{autossh}, but it
15097 can also be run as a Guix service. This latter use case is documented
15100 AutoSSH can be used to forward local traffic to a remote machine using
15101 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
15104 For example, to specify a service running autossh as the user
15105 @code{pino} and forwarding all local connections to port @code{8081} to
15106 @code{remote:8081} using an SSH tunnel, add this call to the operating
15107 system's @code{services} field:
15110 (service autossh-service-type
15111 (autossh-configuration
15113 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
15117 @deftp {Data Type} autossh-configuration
15118 This data type represents the configuration of an AutoSSH service.
15122 @item @code{user} (default @code{"autossh"})
15123 The user as which the AutoSSH service is to be run.
15124 This assumes that the specified user exists.
15126 @item @code{poll} (default @code{600})
15127 Specifies the connection poll time in seconds.
15129 @item @code{first-poll} (default @code{#f})
15130 Specifies how many seconds AutoSSH waits before the first connection
15131 test. After this first test, polling is resumed at the pace defined in
15132 @code{poll}. When set to @code{#f}, the first poll is not treated
15133 specially and will also use the connection poll specified in
15136 @item @code{gate-time} (default @code{30})
15137 Specifies how many seconds an SSH connection must be active before it is
15138 considered successful.
15140 @item @code{log-level} (default @code{1})
15141 The log level, corresponding to the levels used by syslog---so @code{0}
15142 is the most silent while @code{7} is the chattiest.
15144 @item @code{max-start} (default @code{#f})
15145 The maximum number of times SSH may be (re)started before AutoSSH exits.
15146 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
15148 @item @code{message} (default @code{""})
15149 The message to append to the echo message sent when testing connections.
15151 @item @code{port} (default @code{"0"})
15152 The ports used for monitoring the connection. When set to @code{"0"},
15153 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
15154 a positive integer, ports @var{n} and @var{n}+1 are used for
15155 monitoring the connection, such that port @var{n} is the base
15156 monitoring port and @code{n+1} is the echo port. When set to
15157 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
15158 integers, the ports @var{n} and @var{n}+1 are used for monitoring the
15159 connection, such that port @var{n} is the base monitoring port and
15160 @var{m} is the echo port.
15162 @item @code{ssh-options} (default @code{'()})
15163 The list of command-line arguments to pass to @command{ssh} when it is
15164 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
15165 may cause undefined behaviour.
15170 @defvr {Scheme Variable} %facebook-host-aliases
15171 This variable contains a string for use in @file{/etc/hosts}
15172 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
15173 line contains a entry that maps a known server name of the Facebook
15174 on-line service---e.g., @code{www.facebook.com}---to the local
15175 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
15177 This variable is typically used in the @code{hosts-file} field of an
15178 @code{operating-system} declaration (@pxref{operating-system Reference,
15179 @file{/etc/hosts}}):
15182 (use-modules (gnu) (guix))
15185 (host-name "mymachine")
15188 ;; Create a /etc/hosts file with aliases for "localhost"
15189 ;; and "mymachine", as well as for Facebook servers.
15190 (plain-file "hosts"
15191 (string-append (local-host-aliases host-name)
15192 %facebook-host-aliases))))
15195 This mechanism can prevent programs running locally, such as Web
15196 browsers, from accessing Facebook.
15199 The @code{(gnu services avahi)} provides the following definition.
15201 @defvr {Scheme Variable} avahi-service-type
15202 This is the service that runs @command{avahi-daemon}, a system-wide
15203 mDNS/DNS-SD responder that allows for service discovery and
15204 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
15205 Its value must be a @code{zero-configuration} record---see below.
15207 This service extends the name service cache daemon (nscd) so that it can
15208 resolve @code{.local} host names using
15209 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
15210 Service Switch}, for information on host name resolution.
15212 Additionally, add the @var{avahi} package to the system profile so that
15213 commands such as @command{avahi-browse} are directly usable.
15216 @deftp {Data Type} avahi-configuration
15217 Data type representation the configuration for Avahi.
15221 @item @code{host-name} (default: @code{#f})
15222 If different from @code{#f}, use that as the host name to
15223 publish for this machine; otherwise, use the machine's actual host name.
15225 @item @code{publish?} (default: @code{#t})
15226 When true, allow host names and services to be published (broadcast) over the
15229 @item @code{publish-workstation?} (default: @code{#t})
15230 When true, @command{avahi-daemon} publishes the machine's host name and IP
15231 address via mDNS on the local network. To view the host names published on
15232 your local network, you can run:
15235 avahi-browse _workstation._tcp
15238 @item @code{wide-area?} (default: @code{#f})
15239 When true, DNS-SD over unicast DNS is enabled.
15241 @item @code{ipv4?} (default: @code{#t})
15242 @itemx @code{ipv6?} (default: @code{#t})
15243 These fields determine whether to use IPv4/IPv6 sockets.
15245 @item @code{domains-to-browse} (default: @code{'()})
15246 This is a list of domains to browse.
15250 @deffn {Scheme Variable} openvswitch-service-type
15251 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
15252 service, whose value should be an @code{openvswitch-configuration}
15256 @deftp {Data Type} openvswitch-configuration
15257 Data type representing the configuration of Open vSwitch, a multilayer
15258 virtual switch which is designed to enable massive network automation
15259 through programmatic extension.
15262 @item @code{package} (default: @var{openvswitch})
15263 Package object of the Open vSwitch.
15268 @defvr {Scheme Variable} pagekite-service-type
15269 This is the service type for the @uref{https://pagekite.net, PageKite} service,
15270 a tunneling solution for making localhost servers publicly visible, even from
15271 behind restrictive firewalls or NAT without forwarded ports. The value for
15272 this service type is a @code{pagekite-configuration} record.
15274 Here's an example exposing the local HTTP and SSH daemons:
15277 (service pagekite-service-type
15278 (pagekite-configuration
15279 (kites '("http:@@kitename:localhost:80:@@kitesecret"
15280 "raw/22:@@kitename:localhost:22:@@kitesecret"))
15281 (extra-file "/etc/pagekite.rc")))
15285 @deftp {Data Type} pagekite-configuration
15286 Data type representing the configuration of PageKite.
15289 @item @code{package} (default: @var{pagekite})
15290 Package object of PageKite.
15292 @item @code{kitename} (default: @code{#f})
15293 PageKite name for authenticating to the frontend server.
15295 @item @code{kitesecret} (default: @code{#f})
15296 Shared secret for authenticating to the frontend server. You should probably
15297 put this inside @code{extra-file} instead.
15299 @item @code{frontend} (default: @code{#f})
15300 Connect to the named PageKite frontend server instead of the
15301 @uref{https://pagekite.net,,pagekite.net} service.
15303 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
15304 List of service kites to use. Exposes HTTP on port 80 by default. The format
15305 is @code{proto:kitename:host:port:secret}.
15307 @item @code{extra-file} (default: @code{#f})
15308 Extra configuration file to read, which you are expected to create manually.
15309 Use this to add additional options and manage shared secrets out-of-band.
15314 @node Unattended Upgrades
15315 @subsection Unattended Upgrades
15317 @cindex unattended upgrades
15318 @cindex upgrades, unattended
15319 Guix provides a service to perform @emph{unattended upgrades}:
15320 periodically, the system automatically reconfigures itself from the
15321 latest Guix. Guix System has several properties that make unattended
15326 upgrades are transactional (either the upgrade succeeds or it fails, but
15327 you cannot end up with an ``in-between'' system state);
15329 the upgrade log is kept---you can view it with @command{guix system
15330 list-generations}---and you can roll back to any previous generation,
15331 should the upgraded system fail to behave as intended;
15333 channel code is authenticated so you know you can only run genuine code
15334 (@pxref{Channels});
15336 @command{guix system reconfigure} prevents downgrades, which makes it
15337 immune to @dfn{downgrade attacks}.
15340 To set up unattended upgrades, add an instance of
15341 @code{unattended-upgrade-service-type} like the one below to the list of
15342 your operating system services:
15345 (service unattended-upgrade-service-type)
15348 The defaults above set up weekly upgrades: every Sunday at midnight.
15349 You do not need to provide the operating system configuration file: it
15350 uses @file{/run/current-system/configuration.scm}, which ensures it
15351 always uses your latest configuration---@pxref{provenance-service-type},
15352 for more information about this file.
15354 There are several things that can be configured, in particular the
15355 periodicity and services (daemons) to be restarted upon completion.
15356 When the upgrade is successful, the service takes care of deleting
15357 system generations older that some threshold, as per @command{guix
15358 system delete-generations}. See the reference below for details.
15360 To ensure that upgrades are actually happening, you can run
15361 @command{guix system describe}. To investigate upgrade failures, visit
15362 the unattended upgrade log file (see below).
15364 @defvr {Scheme Variable} unattended-upgrade-service-type
15365 This is the service type for unattended upgrades. It sets up an mcron
15366 job (@pxref{Scheduled Job Execution}) that runs @command{guix system
15367 reconfigure} from the latest version of the specified channels.
15369 Its value must be a @code{unattended-upgrade-configuration} record (see
15373 @deftp {Data Type} unattended-upgrade-configuration
15374 This data type represents the configuration of the unattended upgrade
15375 service. The following fields are available:
15378 @item @code{schedule} (default: @code{"30 01 * * 0"})
15379 This is the schedule of upgrades, expressed as a gexp containing an
15380 mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
15381 mcron, GNU@tie{}mcron}).
15383 @item @code{channels} (default: @code{#~%default-channels})
15384 This gexp specifies the channels to use for the upgrade
15385 (@pxref{Channels}). By default, the tip of the official @code{guix}
15388 @item @code{services-to-restart} (default: @code{'(mcron)})
15389 This field specifies the Shepherd services to restart when the upgrade
15392 Those services are restarted right away upon completion, as with
15393 @command{herd restart}, which ensures that the latest version is
15394 running---remember that by default @command{guix system reconfigure}
15395 only restarts services that are not currently running, which is
15396 conservative: it minimizes disruption but leaves outdated services
15399 By default, the @code{mcron} service is restarted. This ensures that
15400 the latest version of the unattended upgrade job will be used next time.
15402 @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
15403 This is the expiration time in seconds for system generations. System
15404 generations older that this amount of time are deleted with
15405 @command{guix system delete-generations} when an upgrade completes.
15408 The unattended upgrade service does not run the garbage collector. You
15409 will probably want to set up your own mcron job to run @command{guix gc}
15413 @item @code{maximum-duration} (default: @code{3600})
15414 Maximum duration in seconds for the upgrade; past that time, the upgrade
15417 This is primarily useful to ensure the upgrade does not end up
15418 rebuilding or re-downloading ``the world''.
15420 @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
15421 File where unattended upgrades are logged.
15426 @subsection X Window
15429 @cindex X Window System
15430 @cindex login manager
15431 Support for the X Window graphical display system---specifically
15432 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
15433 there is no @code{xorg-service} procedure. Instead, the X server is
15434 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
15437 @cindex GNOME, login manager
15438 GDM of course allows users to log in into window managers and desktop
15439 environments other than GNOME; for those using GNOME, GDM is required for
15440 features such as automatic screen locking.
15442 @cindex window manager
15443 To use X11, you must install at least one @dfn{window manager}---for
15444 example the @code{windowmaker} or @code{openbox} packages---preferably
15445 by adding it to the @code{packages} field of your operating system
15446 definition (@pxref{operating-system Reference, system-wide packages}).
15448 @defvr {Scheme Variable} gdm-service-type
15449 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
15450 Desktop Manager} (GDM), a program that manages graphical display servers and
15451 handles graphical user logins. Its value must be a @code{gdm-configuration}
15454 @cindex session types (X11)
15455 @cindex X11 session types
15456 GDM looks for @dfn{session types} described by the @file{.desktop} files in
15457 @file{/run/current-system/profile/share/xsessions} and allows users to choose
15458 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
15459 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
15460 set of packages automatically makes them available at the log-in screen.
15462 In addition, @file{~/.xsession} files are honored. When available,
15463 @file{~/.xsession} must be an executable that starts a window manager
15464 and/or other X clients.
15467 @deftp {Data Type} gdm-configuration
15469 @item @code{auto-login?} (default: @code{#f})
15470 @itemx @code{default-user} (default: @code{#f})
15471 When @code{auto-login?} is false, GDM presents a log-in screen.
15473 When @code{auto-login?} is true, GDM logs in directly as
15474 @code{default-user}.
15476 @item @code{debug?} (default: @code{#f})
15477 When true, GDM writes debug messages to its log.
15479 @item @code{gnome-shell-assets} (default: ...)
15480 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
15482 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
15483 Configuration of the Xorg graphical server.
15485 @item @code{xsession} (default: @code{(xinitrc)})
15486 Script to run before starting a X session.
15488 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
15489 File name of the @code{dbus-daemon} executable.
15491 @item @code{gdm} (default: @code{gdm})
15492 The GDM package to use.
15496 @defvr {Scheme Variable} slim-service-type
15497 This is the type for the SLiM graphical login manager for X11.
15499 Like GDM, SLiM looks for session types described by @file{.desktop} files and
15500 allows users to choose a session from the log-in screen using @kbd{F1}. It
15501 also honors @file{~/.xsession} files.
15503 Unlike GDM, SLiM does not spawn the user session on a different VT after
15504 logging in, which means that you can only start one graphical session. If you
15505 want to be able to run multiple graphical sessions at the same time you have
15506 to add multiple SLiM services to your system services. The following example
15507 shows how to replace the default GDM service with two SLiM services on tty7
15511 (use-modules (gnu services)
15512 (gnu services desktop)
15513 (gnu services xorg)
15514 (srfi srfi-1)) ;for 'remove'
15518 (services (cons* (service slim-service-type (slim-configuration
15521 (service slim-service-type (slim-configuration
15524 (remove (lambda (service)
15525 (eq? (service-kind service) gdm-service-type))
15526 %desktop-services))))
15531 @deftp {Data Type} slim-configuration
15532 Data type representing the configuration of @code{slim-service-type}.
15535 @item @code{allow-empty-passwords?} (default: @code{#t})
15536 Whether to allow logins with empty passwords.
15538 @item @code{auto-login?} (default: @code{#f})
15539 @itemx @code{default-user} (default: @code{""})
15540 When @code{auto-login?} is false, SLiM presents a log-in screen.
15542 When @code{auto-login?} is true, SLiM logs in directly as
15543 @code{default-user}.
15545 @item @code{theme} (default: @code{%default-slim-theme})
15546 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
15547 The graphical theme to use and its name.
15549 @item @code{auto-login-session} (default: @code{#f})
15550 If true, this must be the name of the executable to start as the default
15551 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
15553 If false, a session described by one of the available @file{.desktop}
15554 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
15558 You must install at least one window manager in the system profile or in
15559 your user profile. Failing to do that, if @code{auto-login-session} is
15560 false, you will be unable to log in.
15563 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
15564 Configuration of the Xorg graphical server.
15566 @item @code{display} (default @code{":0"})
15567 The display on which to start the Xorg graphical server.
15569 @item @code{vt} (default @code{"vt7"})
15570 The VT on which to start the Xorg graphical server.
15572 @item @code{xauth} (default: @code{xauth})
15573 The XAuth package to use.
15575 @item @code{shepherd} (default: @code{shepherd})
15576 The Shepherd package used when invoking @command{halt} and
15579 @item @code{sessreg} (default: @code{sessreg})
15580 The sessreg package used in order to register the session.
15582 @item @code{slim} (default: @code{slim})
15583 The SLiM package to use.
15587 @defvr {Scheme Variable} %default-theme
15588 @defvrx {Scheme Variable} %default-theme-name
15589 The default SLiM theme and its name.
15593 @deftp {Data Type} sddm-configuration
15594 This is the data type representing the SDDM service configuration.
15597 @item @code{display-server} (default: "x11")
15598 Select display server to use for the greeter. Valid values are
15599 @samp{"x11"} or @samp{"wayland"}.
15601 @item @code{numlock} (default: "on")
15602 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
15604 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
15605 Command to run when halting.
15607 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
15608 Command to run when rebooting.
15610 @item @code{theme} (default "maldives")
15611 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
15612 @samp{"maldives"} or @samp{"maya"}.
15614 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
15615 Directory to look for themes.
15617 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
15618 Directory to look for faces.
15620 @item @code{default-path} (default "/run/current-system/profile/bin")
15621 Default PATH to use.
15623 @item @code{minimum-uid} (default: 1000)
15624 Minimum UID displayed in SDDM and allowed for log-in.
15626 @item @code{maximum-uid} (default: 2000)
15627 Maximum UID to display in SDDM.
15629 @item @code{remember-last-user?} (default #t)
15630 Remember last user.
15632 @item @code{remember-last-session?} (default #t)
15633 Remember last session.
15635 @item @code{hide-users} (default "")
15636 Usernames to hide from SDDM greeter.
15638 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
15639 Users with shells listed will be hidden from the SDDM greeter.
15641 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
15642 Script to run before starting a wayland session.
15644 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
15645 Directory to look for desktop files starting wayland sessions.
15647 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
15648 Configuration of the Xorg graphical server.
15650 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
15653 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
15656 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
15657 Script to run after starting xorg-server.
15659 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
15660 Script to run before stopping xorg-server.
15662 @item @code{xsession-command} (default: @code{xinitrc})
15663 Script to run before starting a X session.
15665 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
15666 Directory to look for desktop files starting X sessions.
15668 @item @code{minimum-vt} (default: 7)
15671 @item @code{auto-login-user} (default "")
15672 User to use for auto-login.
15674 @item @code{auto-login-session} (default "")
15675 Desktop file to use for auto-login.
15677 @item @code{relogin?} (default #f)
15678 Relogin after logout.
15683 @cindex login manager
15685 @defvr {Scheme Variable} sddm-service-type
15686 This is the type of the service to run the
15687 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
15688 must be a @code{sddm-configuration} record (see below).
15690 Here's an example use:
15693 (service sddm-service-type
15694 (sddm-configuration
15695 (auto-login-user "alice")
15696 (auto-login-session "xfce.desktop")))
15700 @deftp {Data Type} sddm-configuration
15701 This data type represents the configuration of the SDDM login manager.
15702 The available fields are:
15705 @item @code{sddm} (default: @code{sddm})
15706 The SDDM package to use.
15708 @item @code{display-server} (default: @code{"x11"})
15709 This must be either @code{"x11"} or @code{"wayland"}.
15711 @c FIXME: Add more fields.
15713 @item @code{auto-login-user} (default: @code{""})
15714 If non-empty, this is the user account under which to log in
15717 @item @code{auto-login-session} (default: @code{""})
15718 If non-empty, this is the @file{.desktop} file name to use as the
15719 auto-login session.
15723 @cindex Xorg, configuration
15724 @deftp {Data Type} xorg-configuration
15725 This data type represents the configuration of the Xorg graphical display
15726 server. Note that there is no Xorg service; instead, the X server is started
15727 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
15728 of these display managers aggregates an @code{xorg-configuration} record.
15731 @item @code{modules} (default: @code{%default-xorg-modules})
15732 This is a list of @dfn{module packages} loaded by the Xorg
15733 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
15735 @item @code{fonts} (default: @code{%default-xorg-fonts})
15736 This is a list of font directories to add to the server's @dfn{font path}.
15738 @item @code{drivers} (default: @code{'()})
15739 This must be either the empty list, in which case Xorg chooses a graphics
15740 driver automatically, or a list of driver names that will be tried in this
15741 order---e.g., @code{("modesetting" "vesa")}.
15743 @item @code{resolutions} (default: @code{'()})
15744 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
15745 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
15748 @cindex keyboard layout, for Xorg
15749 @cindex keymap, for Xorg
15750 @item @code{keyboard-layout} (default: @code{#f})
15751 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
15752 English (``qwerty'') for a 105-key PC keyboard.
15754 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
15755 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
15756 information on how to specify the keyboard layout.
15758 @item @code{extra-config} (default: @code{'()})
15759 This is a list of strings or objects appended to the configuration file. It
15760 is used to pass extra text to be added verbatim to the configuration file.
15762 @item @code{server} (default: @code{xorg-server})
15763 This is the package providing the Xorg server.
15765 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
15766 This is the list of command-line arguments to pass to the X server. The
15767 default is @code{-nolisten tcp}.
15771 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
15772 [@var{login-manager-service-type}]
15773 Tell the log-in manager (of type @var{login-manager-service-type}) to use
15774 @var{config}, an @code{<xorg-configuration>} record.
15776 Since the Xorg configuration is embedded in the log-in manager's
15777 configuration---e.g., @code{gdm-configuration}---this procedure provides a
15778 shorthand to set the Xorg configuration.
15781 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
15782 Return a @code{startx} script in which the modules, fonts, etc. specified
15783 in @var{config}, are available. The result should be used in place of
15786 Usually the X server is started by a login manager.
15790 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
15791 Add @var{package}, a package for a screen locker or screen saver whose
15792 command is @var{program}, to the set of setuid programs and add a PAM entry
15793 for it. For example:
15796 (screen-locker-service xlockmore "xlock")
15799 makes the good ol' XlockMore usable.
15803 @node Printing Services
15804 @subsection Printing Services
15806 @cindex printer support with CUPS
15807 The @code{(gnu services cups)} module provides a Guix service definition
15808 for the CUPS printing service. To add printer support to a Guix
15809 system, add a @code{cups-service} to the operating system definition:
15811 @deffn {Scheme Variable} cups-service-type
15812 The service type for the CUPS print server. Its value should be a valid
15813 CUPS configuration (see below). To use the default settings, simply
15816 (service cups-service-type)
15820 The CUPS configuration controls the basic things about your CUPS
15821 installation: what interfaces it listens on, what to do if a print job
15822 fails, how much logging to do, and so on. To actually add a printer,
15823 you have to visit the @url{http://localhost:631} URL, or use a tool such
15824 as GNOME's printer configuration services. By default, configuring a
15825 CUPS service will generate a self-signed certificate if needed, for
15826 secure connections to the print server.
15828 Suppose you want to enable the Web interface of CUPS and also add
15829 support for Epson printers @i{via} the @code{escpr} package and for HP
15830 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
15831 like this (you need to use the @code{(gnu packages cups)} module):
15834 (service cups-service-type
15835 (cups-configuration
15836 (web-interface? #t)
15838 (list cups-filters escpr hplip-minimal))))
15841 Note: If you wish to use the Qt5 based GUI which comes with the hplip
15842 package then it is suggested that you install the @code{hplip} package,
15843 either in your OS configuration file or as your user.
15845 The available configuration parameters follow. Each parameter
15846 definition is preceded by its type; for example, @samp{string-list foo}
15847 indicates that the @code{foo} parameter should be specified as a list of
15848 strings. There is also a way to specify the configuration as a string,
15849 if you have an old @code{cupsd.conf} file that you want to port over
15850 from some other system; see the end for more details.
15852 @c The following documentation was initially generated by
15853 @c (generate-documentation) in (gnu services cups). Manually maintained
15854 @c documentation is better, so we shouldn't hesitate to edit below as
15855 @c needed. However if the change you want to make to this documentation
15856 @c can be done in an automated way, it's probably easier to change
15857 @c (generate-documentation) than to make it below and have to deal with
15858 @c the churn as CUPS updates.
15861 Available @code{cups-configuration} fields are:
15863 @deftypevr {@code{cups-configuration} parameter} package cups
15867 @deftypevr {@code{cups-configuration} parameter} package-list extensions
15868 Drivers and other extensions to the CUPS package.
15871 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
15872 Configuration of where to write logs, what directories to use for print
15873 spools, and related privileged configuration parameters.
15875 Available @code{files-configuration} fields are:
15877 @deftypevr {@code{files-configuration} parameter} log-location access-log
15878 Defines the access log filename. Specifying a blank filename disables
15879 access log generation. The value @code{stderr} causes log entries to be
15880 sent to the standard error file when the scheduler is running in the
15881 foreground, or to the system log daemon when run in the background. The
15882 value @code{syslog} causes log entries to be sent to the system log
15883 daemon. The server name may be included in filenames using the string
15884 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
15886 Defaults to @samp{"/var/log/cups/access_log"}.
15889 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
15890 Where CUPS should cache data.
15892 Defaults to @samp{"/var/cache/cups"}.
15895 @deftypevr {@code{files-configuration} parameter} string config-file-perm
15896 Specifies the permissions for all configuration files that the scheduler
15899 Note that the permissions for the printers.conf file are currently
15900 masked to only allow access from the scheduler user (typically root).
15901 This is done because printer device URIs sometimes contain sensitive
15902 authentication information that should not be generally known on the
15903 system. There is no way to disable this security feature.
15905 Defaults to @samp{"0640"}.
15908 @deftypevr {@code{files-configuration} parameter} log-location error-log
15909 Defines the error log filename. Specifying a blank filename disables
15910 error log generation. The value @code{stderr} causes log entries to be
15911 sent to the standard error file when the scheduler is running in the
15912 foreground, or to the system log daemon when run in the background. The
15913 value @code{syslog} causes log entries to be sent to the system log
15914 daemon. The server name may be included in filenames using the string
15915 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
15917 Defaults to @samp{"/var/log/cups/error_log"}.
15920 @deftypevr {@code{files-configuration} parameter} string fatal-errors
15921 Specifies which errors are fatal, causing the scheduler to exit. The
15926 No errors are fatal.
15929 All of the errors below are fatal.
15932 Browsing initialization errors are fatal, for example failed connections
15933 to the DNS-SD daemon.
15936 Configuration file syntax errors are fatal.
15939 Listen or Port errors are fatal, except for IPv6 failures on the
15940 loopback or @code{any} addresses.
15943 Log file creation or write errors are fatal.
15946 Bad startup file permissions are fatal, for example shared TLS
15947 certificate and key files with world-read permissions.
15950 Defaults to @samp{"all -browse"}.
15953 @deftypevr {@code{files-configuration} parameter} boolean file-device?
15954 Specifies whether the file pseudo-device can be used for new printer
15955 queues. The URI @uref{file:///dev/null} is always allowed.
15957 Defaults to @samp{#f}.
15960 @deftypevr {@code{files-configuration} parameter} string group
15961 Specifies the group name or ID that will be used when executing external
15964 Defaults to @samp{"lp"}.
15967 @deftypevr {@code{files-configuration} parameter} string log-file-perm
15968 Specifies the permissions for all log files that the scheduler writes.
15970 Defaults to @samp{"0644"}.
15973 @deftypevr {@code{files-configuration} parameter} log-location page-log
15974 Defines the page log filename. Specifying a blank filename disables
15975 page log generation. The value @code{stderr} causes log entries to be
15976 sent to the standard error file when the scheduler is running in the
15977 foreground, or to the system log daemon when run in the background. The
15978 value @code{syslog} causes log entries to be sent to the system log
15979 daemon. The server name may be included in filenames using the string
15980 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
15982 Defaults to @samp{"/var/log/cups/page_log"}.
15985 @deftypevr {@code{files-configuration} parameter} string remote-root
15986 Specifies the username that is associated with unauthenticated accesses
15987 by clients claiming to be the root user. The default is @code{remroot}.
15989 Defaults to @samp{"remroot"}.
15992 @deftypevr {@code{files-configuration} parameter} file-name request-root
15993 Specifies the directory that contains print jobs and other HTTP request
15996 Defaults to @samp{"/var/spool/cups"}.
15999 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
16000 Specifies the level of security sandboxing that is applied to print
16001 filters, backends, and other child processes of the scheduler; either
16002 @code{relaxed} or @code{strict}. This directive is currently only
16003 used/supported on macOS.
16005 Defaults to @samp{strict}.
16008 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
16009 Specifies the location of TLS certificates and private keys. CUPS will
16010 look for public and private keys in this directory: @file{.crt} files
16011 for PEM-encoded certificates and corresponding @file{.key} files for
16012 PEM-encoded private keys.
16014 Defaults to @samp{"/etc/cups/ssl"}.
16017 @deftypevr {@code{files-configuration} parameter} file-name server-root
16018 Specifies the directory containing the server configuration files.
16020 Defaults to @samp{"/etc/cups"}.
16023 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
16024 Specifies whether the scheduler calls fsync(2) after writing
16025 configuration or state files.
16027 Defaults to @samp{#f}.
16030 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
16031 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
16034 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
16035 Specifies the directory where temporary files are stored.
16037 Defaults to @samp{"/var/spool/cups/tmp"}.
16040 @deftypevr {@code{files-configuration} parameter} string user
16041 Specifies the user name or ID that is used when running external
16044 Defaults to @samp{"lp"}.
16047 @deftypevr {@code{files-configuration} parameter} string set-env
16048 Set the specified environment variable to be passed to child processes.
16050 Defaults to @samp{"variable value"}.
16054 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
16055 Specifies the logging level for the AccessLog file. The @code{config}
16056 level logs when printers and classes are added, deleted, or modified and
16057 when configuration files are accessed or updated. The @code{actions}
16058 level logs when print jobs are submitted, held, released, modified, or
16059 canceled, and any of the conditions for @code{config}. The @code{all}
16060 level logs all requests.
16062 Defaults to @samp{actions}.
16065 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
16066 Specifies whether to purge job history data automatically when it is no
16067 longer required for quotas.
16069 Defaults to @samp{#f}.
16072 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
16073 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
16074 For example, @samp{"_cups" "_print"} will tell network clients that both
16075 CUPS sharing and IPP Everywhere are supported.
16077 Defaults to @samp{"_cups"}.
16080 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
16081 Specifies which protocols to use for local printer sharing.
16083 Defaults to @samp{dnssd}.
16086 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
16087 Specifies whether the CUPS web interface is advertised.
16089 Defaults to @samp{#f}.
16092 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
16093 Specifies whether shared printers are advertised.
16095 Defaults to @samp{#f}.
16098 @deftypevr {@code{cups-configuration} parameter} string classification
16099 Specifies the security classification of the server. Any valid banner
16100 name can be used, including @samp{"classified"}, @samp{"confidential"},
16101 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
16102 banner can be omitted to disable secure printing functions.
16104 Defaults to @samp{""}.
16107 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
16108 Specifies whether users may override the classification (cover page) of
16109 individual print jobs using the @code{job-sheets} option.
16111 Defaults to @samp{#f}.
16114 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
16115 Specifies the default type of authentication to use.
16117 Defaults to @samp{Basic}.
16120 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
16121 Specifies whether encryption will be used for authenticated requests.
16123 Defaults to @samp{Required}.
16126 @deftypevr {@code{cups-configuration} parameter} string default-language
16127 Specifies the default language to use for text and web content.
16129 Defaults to @samp{"en"}.
16132 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
16133 Specifies the default paper size for new print queues. @samp{"Auto"}
16134 uses a locale-specific default, while @samp{"None"} specifies there is
16135 no default paper size. Specific size names are typically
16136 @samp{"Letter"} or @samp{"A4"}.
16138 Defaults to @samp{"Auto"}.
16141 @deftypevr {@code{cups-configuration} parameter} string default-policy
16142 Specifies the default access policy to use.
16144 Defaults to @samp{"default"}.
16147 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
16148 Specifies whether local printers are shared by default.
16150 Defaults to @samp{#t}.
16153 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
16154 Specifies the delay for updating of configuration and state files, in
16155 seconds. A value of 0 causes the update to happen as soon as possible,
16156 typically within a few milliseconds.
16158 Defaults to @samp{30}.
16161 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
16162 Specifies what to do when an error occurs. Possible values are
16163 @code{abort-job}, which will discard the failed print job;
16164 @code{retry-job}, which will retry the job at a later time;
16165 @code{retry-current-job}, which retries the failed job immediately; and
16166 @code{stop-printer}, which stops the printer.
16168 Defaults to @samp{stop-printer}.
16171 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
16172 Specifies the maximum cost of filters that are run concurrently, which
16173 can be used to minimize disk, memory, and CPU resource problems. A
16174 limit of 0 disables filter limiting. An average print to a
16175 non-PostScript printer needs a filter limit of about 200. A PostScript
16176 printer needs about half that (100). Setting the limit below these
16177 thresholds will effectively limit the scheduler to printing a single job
16180 Defaults to @samp{0}.
16183 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
16184 Specifies the scheduling priority of filters that are run to print a
16185 job. The nice value ranges from 0, the highest priority, to 19, the
16188 Defaults to @samp{0}.
16191 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
16192 Specifies whether to do reverse lookups on connecting clients. The
16193 @code{double} setting causes @code{cupsd} to verify that the hostname
16194 resolved from the address matches one of the addresses returned for that
16195 hostname. Double lookups also prevent clients with unregistered
16196 addresses from connecting to your server. Only set this option to
16197 @code{#t} or @code{double} if absolutely required.
16199 Defaults to @samp{#f}.
16202 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
16203 Specifies the number of seconds to wait before killing the filters and
16204 backend associated with a canceled or held job.
16206 Defaults to @samp{30}.
16209 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
16210 Specifies the interval between retries of jobs in seconds. This is
16211 typically used for fax queues but can also be used with normal print
16212 queues whose error policy is @code{retry-job} or
16213 @code{retry-current-job}.
16215 Defaults to @samp{30}.
16218 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
16219 Specifies the number of retries that are done for jobs. This is
16220 typically used for fax queues but can also be used with normal print
16221 queues whose error policy is @code{retry-job} or
16222 @code{retry-current-job}.
16224 Defaults to @samp{5}.
16227 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
16228 Specifies whether to support HTTP keep-alive connections.
16230 Defaults to @samp{#t}.
16233 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
16234 Specifies how long an idle client connection remains open, in seconds.
16236 Defaults to @samp{30}.
16239 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
16240 Specifies the maximum size of print files, IPP requests, and HTML form
16241 data. A limit of 0 disables the limit check.
16243 Defaults to @samp{0}.
16246 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
16247 Listens on the specified interfaces for connections. Valid values are
16248 of the form @var{address}:@var{port}, where @var{address} is either an
16249 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
16250 indicate all addresses. Values can also be file names of local UNIX
16251 domain sockets. The Listen directive is similar to the Port directive
16252 but allows you to restrict access to specific interfaces or networks.
16255 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
16256 Specifies the number of pending connections that will be allowed. This
16257 normally only affects very busy servers that have reached the MaxClients
16258 limit, but can also be triggered by large numbers of simultaneous
16259 connections. When the limit is reached, the operating system will
16260 refuse additional connections until the scheduler can accept the pending
16263 Defaults to @samp{128}.
16266 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
16267 Specifies a set of additional access controls.
16269 Available @code{location-access-controls} fields are:
16271 @deftypevr {@code{location-access-controls} parameter} file-name path
16272 Specifies the URI path to which the access control applies.
16275 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
16276 Access controls for all access to this path, in the same format as the
16277 @code{access-controls} of @code{operation-access-control}.
16279 Defaults to @samp{()}.
16282 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
16283 Access controls for method-specific access to this path.
16285 Defaults to @samp{()}.
16287 Available @code{method-access-controls} fields are:
16289 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
16290 If @code{#t}, apply access controls to all methods except the listed
16291 methods. Otherwise apply to only the listed methods.
16293 Defaults to @samp{#f}.
16296 @deftypevr {@code{method-access-controls} parameter} method-list methods
16297 Methods to which this access control applies.
16299 Defaults to @samp{()}.
16302 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
16303 Access control directives, as a list of strings. Each string should be
16304 one directive, such as @samp{"Order allow,deny"}.
16306 Defaults to @samp{()}.
16311 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
16312 Specifies the number of debugging messages that are retained for logging
16313 if an error occurs in a print job. Debug messages are logged regardless
16314 of the LogLevel setting.
16316 Defaults to @samp{100}.
16319 @deftypevr {@code{cups-configuration} parameter} log-level log-level
16320 Specifies the level of logging for the ErrorLog file. The value
16321 @code{none} stops all logging while @code{debug2} logs everything.
16323 Defaults to @samp{info}.
16326 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
16327 Specifies the format of the date and time in the log files. The value
16328 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
16330 Defaults to @samp{standard}.
16333 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
16334 Specifies the maximum number of simultaneous clients that are allowed by
16337 Defaults to @samp{100}.
16340 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
16341 Specifies the maximum number of simultaneous clients that are allowed
16342 from a single address.
16344 Defaults to @samp{100}.
16347 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
16348 Specifies the maximum number of copies that a user can print of each
16351 Defaults to @samp{9999}.
16354 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
16355 Specifies the maximum time a job may remain in the @code{indefinite}
16356 hold state before it is canceled. A value of 0 disables cancellation of
16359 Defaults to @samp{0}.
16362 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
16363 Specifies the maximum number of simultaneous jobs that are allowed. Set
16364 to 0 to allow an unlimited number of jobs.
16366 Defaults to @samp{500}.
16369 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
16370 Specifies the maximum number of simultaneous jobs that are allowed per
16371 printer. A value of 0 allows up to MaxJobs jobs per printer.
16373 Defaults to @samp{0}.
16376 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
16377 Specifies the maximum number of simultaneous jobs that are allowed per
16378 user. A value of 0 allows up to MaxJobs jobs per user.
16380 Defaults to @samp{0}.
16383 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
16384 Specifies the maximum time a job may take to print before it is
16385 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
16387 Defaults to @samp{10800}.
16390 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
16391 Specifies the maximum size of the log files before they are rotated, in
16392 bytes. The value 0 disables log rotation.
16394 Defaults to @samp{1048576}.
16397 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
16398 Specifies the maximum amount of time to allow between files in a
16399 multiple file print job, in seconds.
16401 Defaults to @samp{300}.
16404 @deftypevr {@code{cups-configuration} parameter} string page-log-format
16405 Specifies the format of PageLog lines. Sequences beginning with percent
16406 (@samp{%}) characters are replaced with the corresponding information,
16407 while all other characters are copied literally. The following percent
16408 sequences are recognized:
16412 insert a single percent character
16415 insert the value of the specified IPP attribute
16418 insert the number of copies for the current page
16421 insert the current page number
16424 insert the current date and time in common log format
16430 insert the printer name
16433 insert the username
16436 A value of the empty string disables page logging. The string @code{%p
16437 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
16438 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
16441 Defaults to @samp{""}.
16444 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
16445 Passes the specified environment variable(s) to child processes; a list
16448 Defaults to @samp{()}.
16451 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
16452 Specifies named access control policies.
16454 Available @code{policy-configuration} fields are:
16456 @deftypevr {@code{policy-configuration} parameter} string name
16457 Name of the policy.
16460 @deftypevr {@code{policy-configuration} parameter} string job-private-access
16461 Specifies an access list for a job's private values. @code{@@ACL} maps
16462 to the printer's requesting-user-name-allowed or
16463 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
16464 owner. @code{@@SYSTEM} maps to the groups listed for the
16465 @code{system-group} field of the @code{files-config} configuration,
16466 which is reified into the @code{cups-files.conf(5)} file. Other
16467 possible elements of the access list include specific user names, and
16468 @code{@@@var{group}} to indicate members of a specific group. The
16469 access list may also be simply @code{all} or @code{default}.
16471 Defaults to @samp{"@@OWNER @@SYSTEM"}.
16474 @deftypevr {@code{policy-configuration} parameter} string job-private-values
16475 Specifies the list of job values to make private, or @code{all},
16476 @code{default}, or @code{none}.
16478 Defaults to @samp{"job-name job-originating-host-name
16479 job-originating-user-name phone"}.
16482 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
16483 Specifies an access list for a subscription's private values.
16484 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
16485 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
16486 owner. @code{@@SYSTEM} maps to the groups listed for the
16487 @code{system-group} field of the @code{files-config} configuration,
16488 which is reified into the @code{cups-files.conf(5)} file. Other
16489 possible elements of the access list include specific user names, and
16490 @code{@@@var{group}} to indicate members of a specific group. The
16491 access list may also be simply @code{all} or @code{default}.
16493 Defaults to @samp{"@@OWNER @@SYSTEM"}.
16496 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
16497 Specifies the list of job values to make private, or @code{all},
16498 @code{default}, or @code{none}.
16500 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
16501 notify-subscriber-user-name notify-user-data"}.
16504 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
16505 Access control by IPP operation.
16507 Defaults to @samp{()}.
16511 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
16512 Specifies whether job files (documents) are preserved after a job is
16513 printed. If a numeric value is specified, job files are preserved for
16514 the indicated number of seconds after printing. Otherwise a boolean
16515 value applies indefinitely.
16517 Defaults to @samp{86400}.
16520 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
16521 Specifies whether the job history is preserved after a job is printed.
16522 If a numeric value is specified, the job history is preserved for the
16523 indicated number of seconds after printing. If @code{#t}, the job
16524 history is preserved until the MaxJobs limit is reached.
16526 Defaults to @samp{#t}.
16529 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
16530 Specifies the amount of time to wait for job completion before
16531 restarting the scheduler.
16533 Defaults to @samp{30}.
16536 @deftypevr {@code{cups-configuration} parameter} string rip-cache
16537 Specifies the maximum amount of memory to use when converting documents
16538 into bitmaps for a printer.
16540 Defaults to @samp{"128m"}.
16543 @deftypevr {@code{cups-configuration} parameter} string server-admin
16544 Specifies the email address of the server administrator.
16546 Defaults to @samp{"root@@localhost.localdomain"}.
16549 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
16550 The ServerAlias directive is used for HTTP Host header validation when
16551 clients connect to the scheduler from external interfaces. Using the
16552 special name @code{*} can expose your system to known browser-based DNS
16553 rebinding attacks, even when accessing sites through a firewall. If the
16554 auto-discovery of alternate names does not work, we recommend listing
16555 each alternate name with a ServerAlias directive instead of using
16558 Defaults to @samp{*}.
16561 @deftypevr {@code{cups-configuration} parameter} string server-name
16562 Specifies the fully-qualified host name of the server.
16564 Defaults to @samp{"localhost"}.
16567 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
16568 Specifies what information is included in the Server header of HTTP
16569 responses. @code{None} disables the Server header. @code{ProductOnly}
16570 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
16571 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
16572 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
16573 the output of the @code{uname} command. @code{Full} reports @code{CUPS
16574 2.0.0 (@var{uname}) IPP/2.0}.
16576 Defaults to @samp{Minimal}.
16579 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
16580 Listens on the specified interfaces for encrypted connections. Valid
16581 values are of the form @var{address}:@var{port}, where @var{address} is
16582 either an IPv6 address enclosed in brackets, an IPv4 address, or
16583 @code{*} to indicate all addresses.
16585 Defaults to @samp{()}.
16588 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
16589 Sets encryption options. By default, CUPS only supports encryption
16590 using TLS v1.0 or higher using known secure cipher suites. Security is
16591 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
16592 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
16593 suites, which are required for some older clients. The @code{AllowSSL3} option
16594 enables SSL v3.0, which is required for some older clients that do not support
16595 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
16596 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
16597 protocol version to TLS v1.1.
16599 Defaults to @samp{()}.
16602 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
16603 Specifies whether the scheduler requires clients to strictly adhere to
16604 the IPP specifications.
16606 Defaults to @samp{#f}.
16609 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
16610 Specifies the HTTP request timeout, in seconds.
16612 Defaults to @samp{300}.
16616 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
16617 Specifies whether the web interface is enabled.
16619 Defaults to @samp{#f}.
16622 At this point you're probably thinking ``oh dear, Guix manual, I like
16623 you but you can stop already with the configuration options''. Indeed.
16624 However, one more point: it could be that you have an existing
16625 @code{cupsd.conf} that you want to use. In that case, you can pass an
16626 @code{opaque-cups-configuration} as the configuration of a
16627 @code{cups-service-type}.
16629 Available @code{opaque-cups-configuration} fields are:
16631 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
16635 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
16636 The contents of the @code{cupsd.conf}, as a string.
16639 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
16640 The contents of the @code{cups-files.conf} file, as a string.
16643 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
16644 strings of the same name, you could instantiate a CUPS service like
16648 (service cups-service-type
16649 (opaque-cups-configuration
16650 (cupsd.conf cupsd.conf)
16651 (cups-files.conf cups-files.conf)))
16655 @node Desktop Services
16656 @subsection Desktop Services
16658 The @code{(gnu services desktop)} module provides services that are
16659 usually useful in the context of a ``desktop'' setup---that is, on a
16660 machine running a graphical display server, possibly with graphical user
16661 interfaces, etc. It also defines services that provide specific desktop
16662 environments like GNOME, Xfce or MATE.
16664 To simplify things, the module defines a variable containing the set of
16665 services that users typically expect on a machine with a graphical
16666 environment and networking:
16668 @defvr {Scheme Variable} %desktop-services
16669 This is a list of services that builds upon @code{%base-services} and
16670 adds or adjusts services for a typical ``desktop'' setup.
16672 In particular, it adds a graphical login manager (@pxref{X Window,
16673 @code{gdm-service-type}}), screen lockers, a network management tool
16674 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
16675 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
16676 energy and color management services, the @code{elogind} login and seat
16677 manager, the Polkit privilege service, the GeoClue location service, the
16678 AccountsService daemon that allows authorized users change system passwords,
16679 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
16680 name service switch service configured to be able to use @code{nss-mdns}
16681 (@pxref{Name Service Switch, mDNS}).
16684 The @code{%desktop-services} variable can be used as the @code{services}
16685 field of an @code{operating-system} declaration (@pxref{operating-system
16686 Reference, @code{services}}).
16688 Additionally, the @code{gnome-desktop-service-type},
16689 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
16690 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
16691 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
16692 services like the backlight adjustment helpers and the power management
16693 utilities are added to the system, extending @code{polkit} and @code{dbus}
16694 appropriately, allowing GNOME to operate with elevated privileges on a
16695 limited number of special-purpose system interfaces. Additionally,
16696 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
16697 metapackage to the system profile. Likewise, adding the Xfce service
16698 not only adds the @code{xfce} metapackage to the system profile, but it
16699 also gives the Thunar file manager the ability to open a ``root-mode''
16700 file management window, if the user authenticates using the
16701 administrator's password via the standard polkit graphical interface.
16702 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
16703 appropriately, allowing MATE to operate with elevated privileges on a
16704 limited number of special-purpose system interfaces. Additionally,
16705 adding a service of type @code{mate-desktop-service-type} adds the MATE
16706 metapackage to the system profile. ``Adding Enlightenment'' means that
16707 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
16708 are set as setuid, allowing Enlightenment's screen locker and other
16709 functionality to work as expected.
16711 The desktop environments in Guix use the Xorg display server by
16712 default. If you'd like to use the newer display server protocol
16713 called Wayland, you need to use the @code{sddm-service} instead of
16714 GDM as the graphical login manager. You should then
16715 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
16716 also try starting GNOME on Wayland manually from a TTY with the
16717 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
16718 gnome-session``. Currently only GNOME has support for Wayland.
16720 @defvr {Scheme Variable} gnome-desktop-service-type
16721 This is the type of the service that adds the @uref{https://www.gnome.org,
16722 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
16723 object (see below).
16725 This service adds the @code{gnome} package to the system profile, and extends
16726 polkit with the actions from @code{gnome-settings-daemon}.
16729 @deftp {Data Type} gnome-desktop-configuration
16730 Configuration record for the GNOME desktop environment.
16733 @item @code{gnome} (default: @code{gnome})
16734 The GNOME package to use.
16738 @defvr {Scheme Variable} xfce-desktop-service-type
16739 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
16740 desktop environment. Its value is an @code{xfce-desktop-configuration} object
16743 This service adds the @code{xfce} package to the system profile, and
16744 extends polkit with the ability for @code{thunar} to manipulate the file
16745 system as root from within a user session, after the user has authenticated
16746 with the administrator's password.
16749 @deftp {Data Type} xfce-desktop-configuration
16750 Configuration record for the Xfce desktop environment.
16753 @item @code{xfce} (default: @code{xfce})
16754 The Xfce package to use.
16758 @deffn {Scheme Variable} mate-desktop-service-type
16759 This is the type of the service that runs the @uref{https://mate-desktop.org/,
16760 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
16761 object (see below).
16763 This service adds the @code{mate} package to the system
16764 profile, and extends polkit with the actions from
16765 @code{mate-settings-daemon}.
16768 @deftp {Data Type} mate-desktop-configuration
16769 Configuration record for the MATE desktop environment.
16772 @item @code{mate} (default: @code{mate})
16773 The MATE package to use.
16777 @deffn {Scheme Variable} enlightenment-desktop-service-type
16778 Return a service that adds the @code{enlightenment} package to the system
16779 profile, and extends dbus with actions from @code{efl}.
16782 @deftp {Data Type} enlightenment-desktop-service-configuration
16784 @item @code{enlightenment} (default: @code{enlightenment})
16785 The enlightenment package to use.
16789 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
16790 the default @code{%desktop-services} variable doesn't include any of
16791 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
16792 @code{%desktop-services} in the @code{services} field of your
16793 @code{operating-system}:
16796 (use-modules (gnu))
16797 (use-service-modules desktop)
16800 ;; cons* adds items to the list given as its last argument.
16801 (services (cons* (service gnome-desktop-service-type)
16802 (service xfce-desktop-service)
16803 %desktop-services))
16807 These desktop environments will then be available as options in the
16808 graphical login window.
16810 The actual service definitions included in @code{%desktop-services} and
16811 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
16812 are described below.
16814 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
16815 Return a service that runs the ``system bus'', using @var{dbus}, with
16816 support for @var{services}.
16818 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
16819 facility. Its system bus is used to allow system services to communicate
16820 and to be notified of system-wide events.
16822 @var{services} must be a list of packages that provide an
16823 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
16824 and policy files. For example, to allow avahi-daemon to use the system bus,
16825 @var{services} must be equal to @code{(list avahi)}.
16828 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
16829 Return a service that runs the @code{elogind} login and
16830 seat management daemon. @uref{https://github.com/elogind/elogind,
16831 Elogind} exposes a D-Bus interface that can be used to know which users
16832 are logged in, know what kind of sessions they have open, suspend the
16833 system, inhibit system suspend, reboot the system, and other tasks.
16835 Elogind handles most system-level power events for a computer, for
16836 example suspending the system when a lid is closed, or shutting it down
16837 when the power button is pressed.
16839 The @var{config} keyword argument specifies the configuration for
16840 elogind, and should be the result of an @code{(elogind-configuration
16841 (@var{parameter} @var{value})...)} invocation. Available parameters and
16842 their default values are:
16845 @item kill-user-processes?
16847 @item kill-only-users
16849 @item kill-exclude-users
16851 @item inhibit-delay-max-seconds
16853 @item handle-power-key
16855 @item handle-suspend-key
16857 @item handle-hibernate-key
16859 @item handle-lid-switch
16861 @item handle-lid-switch-docked
16863 @item power-key-ignore-inhibited?
16865 @item suspend-key-ignore-inhibited?
16867 @item hibernate-key-ignore-inhibited?
16869 @item lid-switch-ignore-inhibited?
16871 @item holdoff-timeout-seconds
16875 @item idle-action-seconds
16877 @item runtime-directory-size-percent
16879 @item runtime-directory-size
16883 @item suspend-state
16884 @code{("mem" "standby" "freeze")}
16887 @item hibernate-state
16889 @item hibernate-mode
16890 @code{("platform" "shutdown")}
16891 @item hybrid-sleep-state
16893 @item hybrid-sleep-mode
16894 @code{("suspend" "platform" "shutdown")}
16898 @deffn {Scheme Procedure} accountsservice-service @
16899 [#:accountsservice @var{accountsservice}]
16900 Return a service that runs AccountsService, a system service that can
16901 list available accounts, change their passwords, and so on.
16902 AccountsService integrates with PolicyKit to enable unprivileged users
16903 to acquire the capability to modify their system configuration.
16904 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
16905 accountsservice web site} for more information.
16907 The @var{accountsservice} keyword argument is the @code{accountsservice}
16908 package to expose as a service.
16911 @deffn {Scheme Procedure} polkit-service @
16912 [#:polkit @var{polkit}]
16913 Return a service that runs the
16914 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
16915 management service}, which allows system administrators to grant access to
16916 privileged operations in a structured way. By querying the Polkit service, a
16917 privileged system component can know when it should grant additional
16918 capabilities to ordinary users. For example, an ordinary user can be granted
16919 the capability to suspend the system if the user is logged in locally.
16922 @defvr {Scheme Variable} polkit-wheel-service
16923 Service that adds the @code{wheel} group as admins to the Polkit
16924 service. This makes it so that users in the @code{wheel} group are queried
16925 for their own passwords when performing administrative actions instead of
16926 @code{root}'s, similar to the behaviour used by @code{sudo}.
16929 @defvr {Scheme Variable} upower-service-type
16930 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
16931 system-wide monitor for power consumption and battery levels, with the given
16932 configuration settings.
16934 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
16935 notably used by GNOME.
16938 @deftp {Data Type} upower-configuration
16939 Data type representation the configuration for UPower.
16943 @item @code{upower} (default: @var{upower})
16944 Package to use for @code{upower}.
16946 @item @code{watts-up-pro?} (default: @code{#f})
16947 Enable the Watts Up Pro device.
16949 @item @code{poll-batteries?} (default: @code{#t})
16950 Enable polling the kernel for battery level changes.
16952 @item @code{ignore-lid?} (default: @code{#f})
16953 Ignore the lid state, this can be useful if it's incorrect on a device.
16955 @item @code{use-percentage-for-policy?} (default: @code{#f})
16956 Whether battery percentage based policy should be used. The default is to use
16957 the time left, change to @code{#t} to use the percentage.
16959 @item @code{percentage-low} (default: @code{10})
16960 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16961 at which the battery is considered low.
16963 @item @code{percentage-critical} (default: @code{3})
16964 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16965 at which the battery is considered critical.
16967 @item @code{percentage-action} (default: @code{2})
16968 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16969 at which action will be taken.
16971 @item @code{time-low} (default: @code{1200})
16972 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16973 seconds at which the battery is considered low.
16975 @item @code{time-critical} (default: @code{300})
16976 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16977 seconds at which the battery is considered critical.
16979 @item @code{time-action} (default: @code{120})
16980 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16981 seconds at which action will be taken.
16983 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
16984 The action taken when @code{percentage-action} or @code{time-action} is
16985 reached (depending on the configuration of @code{use-percentage-for-policy?}).
16987 Possible values are:
16997 @code{'hybrid-sleep}.
17003 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
17004 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
17005 UDisks}, a @dfn{disk management} daemon that provides user interfaces
17006 with notifications and ways to mount/unmount disks. Programs that talk
17007 to UDisks include the @command{udisksctl} command, part of UDisks, and
17008 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
17009 it will only be able to use the file-system utilities installed in the
17010 system profile. For example if you want to be able to mount NTFS
17011 file-systems in read and write fashion, you'll need to have
17012 @code{ntfs-3g} installed system-wide.
17015 @deffn {Scheme Variable} colord-service-type
17016 This is the type of the service that runs @command{colord}, a system
17017 service with a D-Bus
17018 interface to manage the color profiles of input and output devices such as
17019 screens and scanners. It is notably used by the GNOME Color Manager graphical
17020 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
17021 site} for more information.
17024 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
17025 Return a configuration allowing an application to access GeoClue
17026 location data. @var{name} is the Desktop ID of the application, without
17027 the @code{.desktop} part. If @var{allowed?} is true, the application
17028 will have access to location information by default. The boolean
17029 @var{system?} value indicates whether an application is a system component
17030 or not. Finally @var{users} is a list of UIDs of all users for which
17031 this application is allowed location info access. An empty users list
17032 means that all users are allowed.
17035 @cindex scanner access
17036 @deffn {Scheme Procedure} sane-service-type
17037 This service provides access to scanners @i{via}
17038 @uref{http://www.sane-project.org, SANE} by installing the necessary udev
17042 @defvr {Scheme Variable} %standard-geoclue-applications
17043 The standard list of well-known GeoClue application configurations,
17044 granting authority to the GNOME date-and-time utility to ask for the
17045 current location in order to set the time zone, and allowing the
17046 IceCat and Epiphany web browsers to request location information.
17047 IceCat and Epiphany both query the user before allowing a web page to
17048 know the user's location.
17051 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
17052 [#:whitelist '()] @
17053 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
17054 [#:submit-data? #f]
17055 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
17056 [#:submission-nick "geoclue"] @
17057 [#:applications %standard-geoclue-applications]
17058 Return a service that runs the GeoClue location service. This service
17059 provides a D-Bus interface to allow applications to request access to a
17060 user's physical location, and optionally to add information to online
17061 location databases. See
17062 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
17063 web site} for more information.
17066 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
17067 [@w{#:auto-enable? #f}]
17068 Return a service that runs the @command{bluetoothd} daemon, which
17069 manages all the Bluetooth devices and provides a number of D-Bus
17070 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
17071 powered automatically at boot, which can be useful when using a
17072 bluetooth keyboard or mouse.
17074 Users need to be in the @code{lp} group to access the D-Bus service.
17077 @defvr {Scheme Variable} gnome-keyring-service-type
17078 This is the type of the service that adds the
17079 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
17080 value is a @code{gnome-keyring-configuration} object (see below).
17082 This service adds the @code{gnome-keyring} package to the system profile
17083 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
17084 a user's login keyring when they log in or setting its password with passwd.
17087 @deftp {Data Type} gnome-keyring-configuration
17088 Configuration record for the GNOME Keyring service.
17091 @item @code{keyring} (default: @code{gnome-keyring})
17092 The GNOME keyring package to use.
17094 @item @code{pam-services}
17095 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
17096 services to extend, where @var{service} is the name of an existing
17097 service to extend and @var{kind} is one of @code{login} or
17100 If @code{login} is given, it adds an optional
17101 @code{pam_gnome_keyring.so} to the auth block without arguments and to
17102 the session block with @code{auto_start}. If @code{passwd} is given, it
17103 adds an optional @code{pam_gnome_keyring.so} to the password block
17106 By default, this field contains ``gdm-password'' with the value @code{login}
17107 and ``passwd'' is with the value @code{passwd}.
17112 @node Sound Services
17113 @subsection Sound Services
17115 @cindex sound support
17117 @cindex PulseAudio, sound support
17119 The @code{(gnu services sound)} module provides a service to configure the
17120 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
17121 preferred ALSA output driver.
17123 @deffn {Scheme Variable} alsa-service-type
17124 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
17125 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
17126 configuration file. The value for this type is a @command{alsa-configuration}
17127 record as in this example:
17130 (service alsa-service-type)
17133 See below for details about @code{alsa-configuration}.
17136 @deftp {Data Type} alsa-configuration
17137 Data type representing the configuration for @code{alsa-service}.
17140 @item @code{alsa-plugins} (default: @var{alsa-plugins})
17141 @code{alsa-plugins} package to use.
17143 @item @code{pulseaudio?} (default: @var{#t})
17144 Whether ALSA applications should transparently be made to use the
17145 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
17147 Using PulseAudio allows you to run several sound-producing applications
17148 at the same time and to individual control them @i{via}
17149 @command{pavucontrol}, among other things.
17151 @item @code{extra-options} (default: @var{""})
17152 String to append to the @file{/etc/asound.conf} file.
17157 Individual users who want to override the system configuration of ALSA can do
17158 it with the @file{~/.asoundrc} file:
17161 # In guix, we have to specify the absolute path for plugins.
17163 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
17166 # Routing ALSA to jack:
17167 # <http://jackaudio.org/faq/routing_alsa.html>.
17171 0 system:playback_1
17172 1 system:playback_2
17189 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
17192 @deffn {Scheme Variable} pulseaudio-service-type
17193 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
17194 sound server. It exists to allow system overrides of the default settings
17195 via @code{pulseaudio-configuration}, see below.
17198 This service overrides per-user configuration files. If you want
17199 PulseAudio to honor configuraton files in @file{~/.config/pulse} you
17200 have to unset the environment variables @env{PULSE_CONFIG} and
17201 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
17205 This service on its own does not ensure, that the @code{pulseaudio} package
17206 exists on your machine. It merely adds configuration files for it, as
17207 detailed below. In the (admittedly unlikely) case, that you find yourself
17208 without a @code{pulseaudio} package, consider enabling it through the
17209 @code{alsa-service-type} above.
17213 @deftp {Data Type} pulseaudio-configuration
17214 Data type representing the configuration for @code{pulseaudio-service}.
17217 @item @var{client-conf} (default: @code{'()})
17218 List of settings to set in @file{client.conf}.
17219 Accepts a list of strings or a symbol-value pairs. A string will be
17220 inserted as-is with a newline added. A pair will be formatted as
17221 ``key = value'', again with a newline added.
17223 @item @var{daemon-conf} (default: @code{'((flat-volumes . no))})
17224 List of settings to set in @file{daemon.conf}, formatted just like
17227 @item @var{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
17228 Script file to use as as @file{default.pa}.
17230 @item @var{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
17231 Script file to use as as @file{system.pa}.
17235 @deffn {Scheme Variable} ladspa-service-type
17236 This service sets the @var{LADSPA_PATH} variable, so that programs, which
17237 respect it, e.g. PulseAudio, can load LADSPA plugins.
17239 The following example will setup the service to enable modules from the
17240 @code{swh-plugins} package:
17243 (service ladspa-service-type
17244 (ladspa-configuration (plugins (list swh-plugins))))
17247 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
17252 @node Database Services
17253 @subsection Database Services
17257 The @code{(gnu services databases)} module provides the following services.
17259 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
17260 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
17261 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
17262 Return a service that runs @var{postgresql}, the PostgreSQL database
17265 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
17266 creates a database cluster with @var{locale} as the default
17267 locale, stored in @var{data-directory}. It then listens on @var{port}.
17269 If the services fails to start, it may be due to an incompatible
17270 cluster already present in @var{data-directory}. Adjust it (or, if you
17271 don't need the cluster anymore, delete @var{data-directory}), then
17272 restart the service.
17274 Peer authentication is used by default and the @code{postgres} user
17275 account has no shell, which prevents the direct execution of @code{psql}
17276 commands as this user. To use @code{psql}, you can temporarily log in
17277 as @code{postgres} using a shell, create a PostgreSQL superuser with the
17278 same name as one of the system users and then create the associated
17282 sudo -u postgres -s /bin/sh
17283 createuser --interactive
17284 createdb $MY_USER_LOGIN # Replace appropriately.
17287 @cindex postgresql extension-packages
17288 Additional extensions are loaded from packages listed in
17289 @var{extension-packages}. Extensions are available at runtime. For instance,
17290 to create a geographic database using the @code{postgis} extension, a user can
17291 configure the postgresql-service as in this example:
17295 (use-package-modules databases geo)
17299 ;; postgresql is required to run `psql' but postgis is not required for
17300 ;; proper operation.
17301 (packages (cons* postgresql %base-packages))
17304 (postgresql-service #:extension-packages (list postgis))
17308 Then the extension becomes visible and you can initialise an empty geographic
17309 database in this way:
17313 > create database postgistest;
17314 > \connect postgistest;
17315 > create extension postgis;
17316 > create extension postgis_topology;
17319 There is no need to add this field for contrib extensions such as hstore or
17320 dblink as they are already loadable by postgresql. This field is only
17321 required to add extensions provided by other packages.
17324 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
17325 Return a service that runs @command{mysqld}, the MySQL or MariaDB
17328 The optional @var{config} argument specifies the configuration for
17329 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
17332 @deftp {Data Type} mysql-configuration
17333 Data type representing the configuration of @var{mysql-service}.
17336 @item @code{mysql} (default: @var{mariadb})
17337 Package object of the MySQL database server, can be either @var{mariadb}
17340 For MySQL, a temporary root password will be displayed at activation time.
17341 For MariaDB, the root password is empty.
17343 @item @code{port} (default: @code{3306})
17344 TCP port on which the database server listens for incoming connections.
17348 @defvr {Scheme Variable} memcached-service-type
17349 This is the service type for the @uref{https://memcached.org/,
17350 Memcached} service, which provides a distributed in memory cache. The
17351 value for the service type is a @code{memcached-configuration} object.
17355 (service memcached-service-type)
17358 @deftp {Data Type} memcached-configuration
17359 Data type representing the configuration of memcached.
17362 @item @code{memcached} (default: @code{memcached})
17363 The Memcached package to use.
17365 @item @code{interfaces} (default: @code{'("0.0.0.0")})
17366 Network interfaces on which to listen.
17368 @item @code{tcp-port} (default: @code{11211})
17369 Port on which to accept connections on,
17371 @item @code{udp-port} (default: @code{11211})
17372 Port on which to accept UDP connections on, a value of 0 will disable
17373 listening on a UDP socket.
17375 @item @code{additional-options} (default: @code{'()})
17376 Additional command line options to pass to @code{memcached}.
17380 @defvr {Scheme Variable} mongodb-service-type
17381 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
17382 The value for the service type is a @code{mongodb-configuration} object.
17386 (service mongodb-service-type)
17389 @deftp {Data Type} mongodb-configuration
17390 Data type representing the configuration of mongodb.
17393 @item @code{mongodb} (default: @code{mongodb})
17394 The MongoDB package to use.
17396 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
17397 The configuration file for MongoDB.
17399 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
17400 This value is used to create the directory, so that it exists and is
17401 owned by the mongodb user. It should match the data-directory which
17402 MongoDB is configured to use through the configuration file.
17406 @defvr {Scheme Variable} redis-service-type
17407 This is the service type for the @uref{https://redis.io/, Redis}
17408 key/value store, whose value is a @code{redis-configuration} object.
17411 @deftp {Data Type} redis-configuration
17412 Data type representing the configuration of redis.
17415 @item @code{redis} (default: @code{redis})
17416 The Redis package to use.
17418 @item @code{bind} (default: @code{"127.0.0.1"})
17419 Network interface on which to listen.
17421 @item @code{port} (default: @code{6379})
17422 Port on which to accept connections on, a value of 0 will disable
17423 listening on a TCP socket.
17425 @item @code{working-directory} (default: @code{"/var/lib/redis"})
17426 Directory in which to store the database and related files.
17430 @node Mail Services
17431 @subsection Mail Services
17435 The @code{(gnu services mail)} module provides Guix service definitions
17436 for email services: IMAP, POP3, and LMTP servers, as well as mail
17437 transport agents (MTAs). Lots of acronyms! These services are detailed
17438 in the subsections below.
17440 @subsubheading Dovecot Service
17442 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
17443 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
17446 By default, Dovecot does not need much configuration; the default
17447 configuration object created by @code{(dovecot-configuration)} will
17448 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
17449 certificate will be generated for TLS-protected connections, though
17450 Dovecot will also listen on cleartext ports by default. There are a
17451 number of options, though, which mail administrators might need to change,
17452 and as is the case with other services, Guix allows the system
17453 administrator to specify these parameters via a uniform Scheme interface.
17455 For example, to specify that mail is located at @code{maildir~/.mail},
17456 one would instantiate the Dovecot service like this:
17459 (dovecot-service #:config
17460 (dovecot-configuration
17461 (mail-location "maildir:~/.mail")))
17464 The available configuration parameters follow. Each parameter
17465 definition is preceded by its type; for example, @samp{string-list foo}
17466 indicates that the @code{foo} parameter should be specified as a list of
17467 strings. There is also a way to specify the configuration as a string,
17468 if you have an old @code{dovecot.conf} file that you want to port over
17469 from some other system; see the end for more details.
17471 @c The following documentation was initially generated by
17472 @c (generate-documentation) in (gnu services mail). Manually maintained
17473 @c documentation is better, so we shouldn't hesitate to edit below as
17474 @c needed. However if the change you want to make to this documentation
17475 @c can be done in an automated way, it's probably easier to change
17476 @c (generate-documentation) than to make it below and have to deal with
17477 @c the churn as dovecot updates.
17479 Available @code{dovecot-configuration} fields are:
17481 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
17482 The dovecot package.
17485 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
17486 A list of IPs or hosts where to listen for connections. @samp{*}
17487 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
17488 interfaces. If you want to specify non-default ports or anything more
17489 complex, customize the address and port fields of the
17490 @samp{inet-listener} of the specific services you are interested in.
17493 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
17494 List of protocols we want to serve. Available protocols include
17495 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
17497 Available @code{protocol-configuration} fields are:
17499 @deftypevr {@code{protocol-configuration} parameter} string name
17500 The name of the protocol.
17503 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
17504 UNIX socket path to the master authentication server to find users.
17505 This is used by imap (for shared users) and lda.
17506 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
17509 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
17510 Space separated list of plugins to load.
17513 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
17514 Maximum number of IMAP connections allowed for a user from each IP
17515 address. NOTE: The username is compared case-sensitively.
17516 Defaults to @samp{10}.
17521 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
17522 List of services to enable. Available services include @samp{imap},
17523 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
17526 Available @code{service-configuration} fields are:
17528 @deftypevr {@code{service-configuration} parameter} string kind
17529 The service kind. Valid values include @code{director},
17530 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
17531 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
17532 @code{tcpwrap}, @code{quota-warning}, or anything else.
17535 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
17536 Listeners for the service. A listener is either a
17537 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
17538 an @code{inet-listener-configuration}.
17539 Defaults to @samp{()}.
17541 Available @code{unix-listener-configuration} fields are:
17543 @deftypevr {@code{unix-listener-configuration} parameter} string path
17544 Path to the file, relative to @code{base-dir} field. This is also used as
17548 @deftypevr {@code{unix-listener-configuration} parameter} string mode
17549 The access mode for the socket.
17550 Defaults to @samp{"0600"}.
17553 @deftypevr {@code{unix-listener-configuration} parameter} string user
17554 The user to own the socket.
17555 Defaults to @samp{""}.
17558 @deftypevr {@code{unix-listener-configuration} parameter} string group
17559 The group to own the socket.
17560 Defaults to @samp{""}.
17564 Available @code{fifo-listener-configuration} fields are:
17566 @deftypevr {@code{fifo-listener-configuration} parameter} string path
17567 Path to the file, relative to @code{base-dir} field. This is also used as
17571 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
17572 The access mode for the socket.
17573 Defaults to @samp{"0600"}.
17576 @deftypevr {@code{fifo-listener-configuration} parameter} string user
17577 The user to own the socket.
17578 Defaults to @samp{""}.
17581 @deftypevr {@code{fifo-listener-configuration} parameter} string group
17582 The group to own the socket.
17583 Defaults to @samp{""}.
17587 Available @code{inet-listener-configuration} fields are:
17589 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
17590 The protocol to listen for.
17593 @deftypevr {@code{inet-listener-configuration} parameter} string address
17594 The address on which to listen, or empty for all addresses.
17595 Defaults to @samp{""}.
17598 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
17599 The port on which to listen.
17602 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
17603 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
17605 Defaults to @samp{#t}.
17610 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
17611 Maximum number of simultaneous client connections per process. Once
17612 this number of connections is received, the next incoming connection
17613 will prompt Dovecot to spawn another process. If set to 0,
17614 @code{default-client-limit} is used instead.
17616 Defaults to @samp{0}.
17620 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
17621 Number of connections to handle before starting a new process.
17622 Typically the only useful values are 0 (unlimited) or 1. 1 is more
17623 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
17624 Defaults to @samp{1}.
17628 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
17629 Maximum number of processes that can exist for this service. If set to
17630 0, @code{default-process-limit} is used instead.
17632 Defaults to @samp{0}.
17636 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
17637 Number of processes to always keep waiting for more connections.
17638 Defaults to @samp{0}.
17641 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
17642 If you set @samp{service-count 0}, you probably need to grow
17644 Defaults to @samp{256000000}.
17649 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
17650 Dict configuration, as created by the @code{dict-configuration}
17653 Available @code{dict-configuration} fields are:
17655 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
17656 A list of key-value pairs that this dict should hold.
17657 Defaults to @samp{()}.
17662 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
17663 A list of passdb configurations, each one created by the
17664 @code{passdb-configuration} constructor.
17666 Available @code{passdb-configuration} fields are:
17668 @deftypevr {@code{passdb-configuration} parameter} string driver
17669 The driver that the passdb should use. Valid values include
17670 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
17672 Defaults to @samp{"pam"}.
17675 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
17676 Space separated list of arguments to the passdb driver.
17677 Defaults to @samp{""}.
17682 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
17683 List of userdb configurations, each one created by the
17684 @code{userdb-configuration} constructor.
17686 Available @code{userdb-configuration} fields are:
17688 @deftypevr {@code{userdb-configuration} parameter} string driver
17689 The driver that the userdb should use. Valid values include
17690 @samp{passwd} and @samp{static}.
17691 Defaults to @samp{"passwd"}.
17694 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
17695 Space separated list of arguments to the userdb driver.
17696 Defaults to @samp{""}.
17699 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
17700 Override fields from passwd.
17701 Defaults to @samp{()}.
17706 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
17707 Plug-in configuration, created by the @code{plugin-configuration}
17711 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
17712 List of namespaces. Each item in the list is created by the
17713 @code{namespace-configuration} constructor.
17715 Available @code{namespace-configuration} fields are:
17717 @deftypevr {@code{namespace-configuration} parameter} string name
17718 Name for this namespace.
17721 @deftypevr {@code{namespace-configuration} parameter} string type
17722 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
17723 Defaults to @samp{"private"}.
17726 @deftypevr {@code{namespace-configuration} parameter} string separator
17727 Hierarchy separator to use. You should use the same separator for
17728 all namespaces or some clients get confused. @samp{/} is usually a good
17729 one. The default however depends on the underlying mail storage
17731 Defaults to @samp{""}.
17734 @deftypevr {@code{namespace-configuration} parameter} string prefix
17735 Prefix required to access this namespace. This needs to be
17736 different for all namespaces. For example @samp{Public/}.
17737 Defaults to @samp{""}.
17740 @deftypevr {@code{namespace-configuration} parameter} string location
17741 Physical location of the mailbox. This is in the same format as
17742 mail_location, which is also the default for it.
17743 Defaults to @samp{""}.
17746 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
17747 There can be only one INBOX, and this setting defines which
17749 Defaults to @samp{#f}.
17752 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
17753 If namespace is hidden, it's not advertised to clients via NAMESPACE
17754 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
17755 useful when converting from another server with different namespaces
17756 which you want to deprecate but still keep working. For example you can
17757 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
17759 Defaults to @samp{#f}.
17762 @deftypevr {@code{namespace-configuration} parameter} boolean list?
17763 Show the mailboxes under this namespace with the LIST command. This
17764 makes the namespace visible for clients that do not support the NAMESPACE
17765 extension. The special @code{children} value lists child mailboxes, but
17766 hides the namespace prefix.
17767 Defaults to @samp{#t}.
17770 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
17771 Namespace handles its own subscriptions. If set to @code{#f}, the
17772 parent namespace handles them. The empty prefix should always have this
17774 Defaults to @samp{#t}.
17777 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
17778 List of predefined mailboxes in this namespace.
17779 Defaults to @samp{()}.
17781 Available @code{mailbox-configuration} fields are:
17783 @deftypevr {@code{mailbox-configuration} parameter} string name
17784 Name for this mailbox.
17787 @deftypevr {@code{mailbox-configuration} parameter} string auto
17788 @samp{create} will automatically create this mailbox.
17789 @samp{subscribe} will both create and subscribe to the mailbox.
17790 Defaults to @samp{"no"}.
17793 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
17794 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
17795 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
17796 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
17797 Defaults to @samp{()}.
17804 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
17805 Base directory where to store runtime data.
17806 Defaults to @samp{"/var/run/dovecot/"}.
17809 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
17810 Greeting message for clients.
17811 Defaults to @samp{"Dovecot ready."}.
17814 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
17815 List of trusted network ranges. Connections from these IPs are
17816 allowed to override their IP addresses and ports (for logging and for
17817 authentication checks). @samp{disable-plaintext-auth} is also ignored
17818 for these networks. Typically you would specify your IMAP proxy servers
17820 Defaults to @samp{()}.
17823 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
17824 List of login access check sockets (e.g.@: tcpwrap).
17825 Defaults to @samp{()}.
17828 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
17829 Show more verbose process titles (in ps). Currently shows user name
17830 and IP address. Useful for seeing who is actually using the IMAP
17831 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
17833 Defaults to @samp{#f}.
17836 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
17837 Should all processes be killed when Dovecot master process shuts down.
17838 Setting this to @code{#f} means that Dovecot can be upgraded without
17839 forcing existing client connections to close (although that could also
17840 be a problem if the upgrade is e.g.@: due to a security fix).
17841 Defaults to @samp{#t}.
17844 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
17845 If non-zero, run mail commands via this many connections to doveadm
17846 server, instead of running them directly in the same process.
17847 Defaults to @samp{0}.
17850 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
17851 UNIX socket or host:port used for connecting to doveadm server.
17852 Defaults to @samp{"doveadm-server"}.
17855 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
17856 List of environment variables that are preserved on Dovecot startup
17857 and passed down to all of its child processes. You can also give
17858 key=value pairs to always set specific settings.
17861 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
17862 Disable LOGIN command and all other plaintext authentications unless
17863 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
17864 matches the local IP (i.e.@: you're connecting from the same computer),
17865 the connection is considered secure and plaintext authentication is
17866 allowed. See also ssl=required setting.
17867 Defaults to @samp{#t}.
17870 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
17871 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
17872 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
17873 for caching to be used.
17874 Defaults to @samp{0}.
17877 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
17878 Time to live for cached data. After TTL expires the cached record
17879 is no longer used, *except* if the main database lookup returns internal
17880 failure. We also try to handle password changes automatically: If
17881 user's previous authentication was successful, but this one wasn't, the
17882 cache isn't used. For now this works only with plaintext
17884 Defaults to @samp{"1 hour"}.
17887 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
17888 TTL for negative hits (user not found, password mismatch).
17889 0 disables caching them completely.
17890 Defaults to @samp{"1 hour"}.
17893 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
17894 List of realms for SASL authentication mechanisms that need them.
17895 You can leave it empty if you don't want to support multiple realms.
17896 Many clients simply use the first one listed here, so keep the default
17898 Defaults to @samp{()}.
17901 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
17902 Default realm/domain to use if none was specified. This is used for
17903 both SASL realms and appending @@domain to username in plaintext
17905 Defaults to @samp{""}.
17908 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
17909 List of allowed characters in username. If the user-given username
17910 contains a character not listed in here, the login automatically fails.
17911 This is just an extra check to make sure user can't exploit any
17912 potential quote escaping vulnerabilities with SQL/LDAP databases. If
17913 you want to allow all characters, set this value to empty.
17914 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
17917 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
17918 Username character translations before it's looked up from
17919 databases. The value contains series of from -> to characters. For
17920 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
17921 translated to @samp{@@}.
17922 Defaults to @samp{""}.
17925 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
17926 Username formatting before it's looked up from databases. You can
17927 use the standard variables here, e.g.@: %Lu would lowercase the username,
17928 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
17929 change the @samp{@@} into @samp{-AT-}. This translation is done after
17930 @samp{auth-username-translation} changes.
17931 Defaults to @samp{"%Lu"}.
17934 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
17935 If you want to allow master users to log in by specifying the master
17936 username within the normal username string (i.e.@: not using SASL
17937 mechanism's support for it), you can specify the separator character
17938 here. The format is then <username><separator><master username>.
17939 UW-IMAP uses @samp{*} as the separator, so that could be a good
17941 Defaults to @samp{""}.
17944 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
17945 Username to use for users logging in with ANONYMOUS SASL
17947 Defaults to @samp{"anonymous"}.
17950 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
17951 Maximum number of dovecot-auth worker processes. They're used to
17952 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
17953 They're automatically created and destroyed as needed.
17954 Defaults to @samp{30}.
17957 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
17958 Host name to use in GSSAPI principal names. The default is to use
17959 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
17960 allow all keytab entries.
17961 Defaults to @samp{""}.
17964 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
17965 Kerberos keytab to use for the GSSAPI mechanism. Will use the
17966 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
17967 need to change the auth service to run as root to be able to read this
17969 Defaults to @samp{""}.
17972 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
17973 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
17974 and @samp{ntlm-auth} helper.
17975 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
17976 Defaults to @samp{#f}.
17979 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
17980 Path for Samba's @samp{ntlm-auth} helper binary.
17981 Defaults to @samp{"/usr/bin/ntlm_auth"}.
17984 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
17985 Time to delay before replying to failed authentications.
17986 Defaults to @samp{"2 secs"}.
17989 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
17990 Require a valid SSL client certificate or the authentication
17992 Defaults to @samp{#f}.
17995 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
17996 Take the username from client's SSL certificate, using
17997 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
17999 Defaults to @samp{#f}.
18002 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
18003 List of wanted authentication mechanisms. Supported mechanisms are:
18004 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
18005 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
18006 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
18007 @samp{disable-plaintext-auth} setting.
18010 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
18011 List of IPs or hostnames to all director servers, including ourself.
18012 Ports can be specified as ip:port. The default port is the same as what
18013 director service's @samp{inet-listener} is using.
18014 Defaults to @samp{()}.
18017 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
18018 List of IPs or hostnames to all backend mail servers. Ranges are
18019 allowed too, like 10.0.0.10-10.0.0.30.
18020 Defaults to @samp{()}.
18023 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
18024 How long to redirect users to a specific server after it no longer
18025 has any connections.
18026 Defaults to @samp{"15 min"}.
18029 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
18030 How the username is translated before being hashed. Useful values
18031 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
18032 are shared within domain.
18033 Defaults to @samp{"%Lu"}.
18036 @deftypevr {@code{dovecot-configuration} parameter} string log-path
18037 Log file to use for error messages. @samp{syslog} logs to syslog,
18038 @samp{/dev/stderr} logs to stderr.
18039 Defaults to @samp{"syslog"}.
18042 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
18043 Log file to use for informational messages. Defaults to
18045 Defaults to @samp{""}.
18048 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
18049 Log file to use for debug messages. Defaults to
18050 @samp{info-log-path}.
18051 Defaults to @samp{""}.
18054 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
18055 Syslog facility to use if you're logging to syslog. Usually if you
18056 don't want to use @samp{mail}, you'll use local0..local7. Also other
18057 standard facilities are supported.
18058 Defaults to @samp{"mail"}.
18061 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
18062 Log unsuccessful authentication attempts and the reasons why they
18064 Defaults to @samp{#f}.
18067 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
18068 In case of password mismatches, log the attempted password. Valid
18069 values are no, plain and sha1. sha1 can be useful for detecting brute
18070 force password attempts vs. user simply trying the same password over
18071 and over again. You can also truncate the value to n chars by appending
18072 ":n" (e.g.@: sha1:6).
18073 Defaults to @samp{"no"}.
18076 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
18077 Even more verbose logging for debugging purposes. Shows for example
18079 Defaults to @samp{#f}.
18082 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
18083 In case of password mismatches, log the passwords and used scheme so
18084 the problem can be debugged. Enabling this also enables
18086 Defaults to @samp{#f}.
18089 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
18090 Enable mail process debugging. This can help you figure out why
18091 Dovecot isn't finding your mails.
18092 Defaults to @samp{#f}.
18095 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
18096 Show protocol level SSL errors.
18097 Defaults to @samp{#f}.
18100 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
18101 Prefix for each line written to log file. % codes are in
18102 strftime(3) format.
18103 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
18106 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
18107 List of elements we want to log. The elements which have a
18108 non-empty variable value are joined together to form a comma-separated
18112 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
18113 Login log format. %s contains @samp{login-log-format-elements}
18114 string, %$ contains the data we want to log.
18115 Defaults to @samp{"%$: %s"}.
18118 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
18119 Log prefix for mail processes. See doc/wiki/Variables.txt for list
18120 of possible variables you can use.
18121 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
18124 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
18125 Format to use for logging mail deliveries. You can use variables:
18128 Delivery status message (e.g.@: @samp{saved to INBOX})
18140 Defaults to @samp{"msgid=%m: %$"}.
18143 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
18144 Location for users' mailboxes. The default is empty, which means
18145 that Dovecot tries to find the mailboxes automatically. This won't work
18146 if the user doesn't yet have any mail, so you should explicitly tell
18147 Dovecot the full location.
18149 If you're using mbox, giving a path to the INBOX
18150 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
18151 where the other mailboxes are kept. This is called the @emph{root mail
18152 directory}, and it must be the first path given in the
18153 @samp{mail-location} setting.
18155 There are a few special variables you can use, e.g.:
18161 user part in user@@domain, same as %u if there's no domain
18163 domain part in user@@domain, empty if there's no domain
18168 See doc/wiki/Variables.txt for full list. Some examples:
18170 @item maildir:~/Maildir
18171 @item mbox:~/mail:INBOX=/var/mail/%u
18172 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
18174 Defaults to @samp{""}.
18177 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
18178 System user and group used to access mails. If you use multiple,
18179 userdb can override these by returning uid or gid fields. You can use
18180 either numbers or names. <doc/wiki/UserIds.txt>.
18181 Defaults to @samp{""}.
18184 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
18186 Defaults to @samp{""}.
18189 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
18190 Group to enable temporarily for privileged operations. Currently
18191 this is used only with INBOX when either its initial creation or
18192 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
18194 Defaults to @samp{""}.
18197 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
18198 Grant access to these supplementary groups for mail processes.
18199 Typically these are used to set up access to shared mailboxes. Note
18200 that it may be dangerous to set these if users can create symlinks
18201 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
18202 could allow a user to delete others' mailboxes, or @code{ln -s
18203 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
18207 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
18208 Allow full file system access to clients. There's no access checks
18209 other than what the operating system does for the active UID/GID. It
18210 works with both maildir and mboxes, allowing you to prefix mailboxes
18211 names with e.g.@: @file{/path/} or @file{~user/}.
18212 Defaults to @samp{#f}.
18215 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
18216 Don't use @code{mmap()} at all. This is required if you store indexes to
18217 shared file systems (NFS or clustered file system).
18218 Defaults to @samp{#f}.
18221 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
18222 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
18223 supports @samp{O_EXCL} since version 3, so this should be safe to use
18224 nowadays by default.
18225 Defaults to @samp{#t}.
18228 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
18229 When to use fsync() or fdatasync() calls:
18232 Whenever necessary to avoid losing important data
18234 Useful with e.g.@: NFS when @code{write()}s are delayed
18236 Never use it (best performance, but crashes can lose data).
18238 Defaults to @samp{"optimized"}.
18241 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
18242 Mail storage exists in NFS. Set this to yes to make Dovecot flush
18243 NFS caches whenever needed. If you're using only a single mail server
18245 Defaults to @samp{#f}.
18248 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
18249 Mail index files also exist in NFS. Setting this to yes requires
18250 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
18251 Defaults to @samp{#f}.
18254 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
18255 Locking method for index files. Alternatives are fcntl, flock and
18256 dotlock. Dotlocking uses some tricks which may create more disk I/O
18257 than other locking methods. NFS users: flock doesn't work, remember to
18258 change @samp{mmap-disable}.
18259 Defaults to @samp{"fcntl"}.
18262 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
18263 Directory in which LDA/LMTP temporarily stores incoming mails >128
18265 Defaults to @samp{"/tmp"}.
18268 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
18269 Valid UID range for users. This is mostly to make sure that users can't
18270 log in as daemons or other system users. Note that denying root logins is
18271 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
18273 Defaults to @samp{500}.
18276 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
18278 Defaults to @samp{0}.
18281 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
18282 Valid GID range for users. Users having non-valid GID as primary group ID
18283 aren't allowed to log in. If user belongs to supplementary groups with
18284 non-valid GIDs, those groups are not set.
18285 Defaults to @samp{1}.
18288 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
18290 Defaults to @samp{0}.
18293 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
18294 Maximum allowed length for mail keyword name. It's only forced when
18295 trying to create new keywords.
18296 Defaults to @samp{50}.
18299 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
18300 List of directories under which chrooting is allowed for mail
18301 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
18302 too). This setting doesn't affect @samp{login-chroot}
18303 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
18304 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
18305 which local users can modify, that may lead to root exploit. Usually
18306 this should be done only if you don't allow shell access for users.
18307 <doc/wiki/Chrooting.txt>.
18308 Defaults to @samp{()}.
18311 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
18312 Default chroot directory for mail processes. This can be overridden
18313 for specific users in user database by giving @samp{/./} in user's home
18314 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
18315 there is no real need to do chrooting, Dovecot doesn't allow users to
18316 access files outside their mail directory anyway. If your home
18317 directories are prefixed with the chroot directory, append @samp{/.} to
18318 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
18319 Defaults to @samp{""}.
18322 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
18323 UNIX socket path to master authentication server to find users.
18324 This is used by imap (for shared users) and lda.
18325 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
18328 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
18329 Directory where to look up mail plugins.
18330 Defaults to @samp{"/usr/lib/dovecot"}.
18333 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
18334 List of plugins to load for all services. Plugins specific to IMAP,
18335 LDA, etc.@: are added to this list in their own .conf files.
18336 Defaults to @samp{()}.
18339 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
18340 The minimum number of mails in a mailbox before updates are done to
18341 cache file. This allows optimizing Dovecot's behavior to do less disk
18342 writes at the cost of more disk reads.
18343 Defaults to @samp{0}.
18346 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
18347 When IDLE command is running, mailbox is checked once in a while to
18348 see if there are any new mails or other changes. This setting defines
18349 the minimum time to wait between those checks. Dovecot can also use
18350 dnotify, inotify and kqueue to find out immediately when changes
18352 Defaults to @samp{"30 secs"}.
18355 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
18356 Save mails with CR+LF instead of plain LF. This makes sending those
18357 mails take less CPU, especially with sendfile() syscall with Linux and
18358 FreeBSD. But it also creates a bit more disk I/O which may just make it
18359 slower. Also note that if other software reads the mboxes/maildirs,
18360 they may handle the extra CRs wrong and cause problems.
18361 Defaults to @samp{#f}.
18364 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
18365 By default LIST command returns all entries in maildir beginning
18366 with a dot. Enabling this option makes Dovecot return only entries
18367 which are directories. This is done by stat()ing each entry, so it
18368 causes more disk I/O.
18369 (For systems setting struct @samp{dirent->d_type} this check is free
18370 and it's done always regardless of this setting).
18371 Defaults to @samp{#f}.
18374 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
18375 When copying a message, do it with hard links whenever possible.
18376 This makes the performance much better, and it's unlikely to have any
18378 Defaults to @samp{#t}.
18381 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
18382 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
18383 directory only when its mtime changes unexpectedly or when we can't find
18384 the mail otherwise.
18385 Defaults to @samp{#f}.
18388 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
18389 Which locking methods to use for locking mbox. There are four
18394 Create <mailbox>.lock file. This is the oldest and most NFS-safe
18395 solution. If you want to use /var/mail/ like directory, the users will
18396 need write access to that directory.
18398 Same as dotlock, but if it fails because of permissions or because there
18399 isn't enough disk space, just skip it.
18401 Use this if possible. Works with NFS too if lockd is used.
18403 May not exist in all systems. Doesn't work with NFS.
18405 May not exist in all systems. Doesn't work with NFS.
18408 You can use multiple locking methods; if you do the order they're declared
18409 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
18410 locking methods as well. Some operating systems don't allow using some of
18411 them simultaneously.
18414 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
18418 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
18419 Maximum time to wait for lock (all of them) before aborting.
18420 Defaults to @samp{"5 mins"}.
18423 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
18424 If dotlock exists but the mailbox isn't modified in any way,
18425 override the lock file after this much time.
18426 Defaults to @samp{"2 mins"}.
18429 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
18430 When mbox changes unexpectedly we have to fully read it to find out
18431 what changed. If the mbox is large this can take a long time. Since
18432 the change is usually just a newly appended mail, it'd be faster to
18433 simply read the new mails. If this setting is enabled, Dovecot does
18434 this but still safely fallbacks to re-reading the whole mbox file
18435 whenever something in mbox isn't how it's expected to be. The only real
18436 downside to this setting is that if some other MUA changes message
18437 flags, Dovecot doesn't notice it immediately. Note that a full sync is
18438 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
18439 Defaults to @samp{#t}.
18442 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
18443 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
18444 EXAMINE, EXPUNGE or CHECK commands. If this is set,
18445 @samp{mbox-dirty-syncs} is ignored.
18446 Defaults to @samp{#f}.
18449 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
18450 Delay writing mbox headers until doing a full write sync (EXPUNGE
18451 and CHECK commands and when closing the mailbox). This is especially
18452 useful for POP3 where clients often delete all mails. The downside is
18453 that our changes aren't immediately visible to other MUAs.
18454 Defaults to @samp{#t}.
18457 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
18458 If mbox size is smaller than this (e.g.@: 100k), don't write index
18459 files. If an index file already exists it's still read, just not
18461 Defaults to @samp{0}.
18464 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
18465 Maximum dbox file size until it's rotated.
18466 Defaults to @samp{10000000}.
18469 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
18470 Maximum dbox file age until it's rotated. Typically in days. Day
18471 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
18473 Defaults to @samp{"1d"}.
18476 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
18477 When creating new mdbox files, immediately preallocate their size to
18478 @samp{mdbox-rotate-size}. This setting currently works only in Linux
18479 with some file systems (ext4, xfs).
18480 Defaults to @samp{#f}.
18483 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
18484 sdbox and mdbox support saving mail attachments to external files,
18485 which also allows single instance storage for them. Other backends
18486 don't support this for now.
18488 WARNING: This feature hasn't been tested much yet. Use at your own risk.
18490 Directory root where to store mail attachments. Disabled, if empty.
18491 Defaults to @samp{""}.
18494 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
18495 Attachments smaller than this aren't saved externally. It's also
18496 possible to write a plugin to disable saving specific attachments
18498 Defaults to @samp{128000}.
18501 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
18502 File system backend to use for saving attachments:
18505 No SiS done by Dovecot (but this might help FS's own deduplication)
18507 SiS with immediate byte-by-byte comparison during saving
18508 @item sis-queue posix
18509 SiS with delayed comparison and deduplication.
18511 Defaults to @samp{"sis posix"}.
18514 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
18515 Hash format to use in attachment filenames. You can add any text and
18516 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
18517 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
18518 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
18519 Defaults to @samp{"%@{sha1@}"}.
18522 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
18524 Defaults to @samp{100}.
18527 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
18529 Defaults to @samp{1000}.
18532 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
18533 Default VSZ (virtual memory size) limit for service processes.
18534 This is mainly intended to catch and kill processes that leak memory
18535 before they eat up everything.
18536 Defaults to @samp{256000000}.
18539 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
18540 Login user is internally used by login processes. This is the most
18541 untrusted user in Dovecot system. It shouldn't have access to anything
18543 Defaults to @samp{"dovenull"}.
18546 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
18547 Internal user is used by unprivileged processes. It should be
18548 separate from login user, so that login processes can't disturb other
18550 Defaults to @samp{"dovecot"}.
18553 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
18554 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
18555 Defaults to @samp{"required"}.
18558 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
18559 PEM encoded X.509 SSL/TLS certificate (public key).
18560 Defaults to @samp{"</etc/dovecot/default.pem"}.
18563 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
18564 PEM encoded SSL/TLS private key. The key is opened before
18565 dropping root privileges, so keep the key file unreadable by anyone but
18567 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
18570 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
18571 If key file is password protected, give the password here.
18572 Alternatively give it when starting dovecot with -p parameter. Since
18573 this file is often world-readable, you may want to place this setting
18574 instead to a different.
18575 Defaults to @samp{""}.
18578 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
18579 PEM encoded trusted certificate authority. Set this only if you
18580 intend to use @samp{ssl-verify-client-cert? #t}. The file should
18581 contain the CA certificate(s) followed by the matching
18582 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
18583 Defaults to @samp{""}.
18586 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
18587 Require that CRL check succeeds for client certificates.
18588 Defaults to @samp{#t}.
18591 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
18592 Request client to send a certificate. If you also want to require
18593 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
18594 Defaults to @samp{#f}.
18597 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
18598 Which field from certificate to use for username. commonName and
18599 x500UniqueIdentifier are the usual choices. You'll also need to set
18600 @samp{auth-ssl-username-from-cert? #t}.
18601 Defaults to @samp{"commonName"}.
18604 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
18605 Minimum SSL protocol version to accept.
18606 Defaults to @samp{"TLSv1"}.
18609 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
18610 SSL ciphers to use.
18611 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
18614 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
18615 SSL crypto device to use, for valid values run "openssl engine".
18616 Defaults to @samp{""}.
18619 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
18620 Address to use when sending rejection mails.
18621 %d expands to recipient domain.
18622 Defaults to @samp{"postmaster@@%d"}.
18625 @deftypevr {@code{dovecot-configuration} parameter} string hostname
18626 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
18627 and in LMTP replies. Default is the system's real hostname@@domain.
18628 Defaults to @samp{""}.
18631 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
18632 If user is over quota, return with temporary failure instead of
18634 Defaults to @samp{#f}.
18637 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
18638 Binary to use for sending mails.
18639 Defaults to @samp{"/usr/sbin/sendmail"}.
18642 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
18643 If non-empty, send mails via this SMTP host[:port] instead of
18645 Defaults to @samp{""}.
18648 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
18649 Subject: header to use for rejection mails. You can use the same
18650 variables as for @samp{rejection-reason} below.
18651 Defaults to @samp{"Rejected: %s"}.
18654 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
18655 Human readable error message for rejection mails. You can use
18668 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
18671 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
18672 Delimiter character between local-part and detail in email
18674 Defaults to @samp{"+"}.
18677 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
18678 Header where the original recipient address (SMTP's RCPT TO:
18679 address) is taken from if not available elsewhere. With dovecot-lda -a
18680 parameter overrides this. A commonly used header for this is
18682 Defaults to @samp{""}.
18685 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
18686 Should saving a mail to a nonexistent mailbox automatically create
18688 Defaults to @samp{#f}.
18691 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
18692 Should automatically created mailboxes be also automatically
18694 Defaults to @samp{#f}.
18697 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
18698 Maximum IMAP command line length. Some clients generate very long
18699 command lines with huge mailboxes, so you may need to raise this if you
18700 get "Too long argument" or "IMAP command line too large" errors
18702 Defaults to @samp{64000}.
18705 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
18706 IMAP logout format string:
18709 total number of bytes read from client
18711 total number of bytes sent to client.
18713 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
18714 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@}"}.
18717 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
18718 Override the IMAP CAPABILITY response. If the value begins with '+',
18719 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
18720 Defaults to @samp{""}.
18723 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
18724 How long to wait between "OK Still here" notifications when client
18726 Defaults to @samp{"2 mins"}.
18729 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
18730 ID field names and values to send to clients. Using * as the value
18731 makes Dovecot use the default value. The following fields have default
18732 values currently: name, version, os, os-version, support-url,
18734 Defaults to @samp{""}.
18737 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
18738 ID fields sent by client to log. * means everything.
18739 Defaults to @samp{""}.
18742 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
18743 Workarounds for various client bugs:
18746 @item delay-newmail
18747 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
18748 CHECK commands. Some clients ignore them otherwise, for example OSX
18749 Mail (<v2.1). Outlook Express breaks more badly though, without this it
18750 may show user "Message no longer in server" errors. Note that OE6
18751 still breaks even with this workaround if synchronization is set to
18754 @item tb-extra-mailbox-sep
18755 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
18756 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
18757 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
18759 @item tb-lsub-flags
18760 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
18761 This makes Thunderbird realize they aren't selectable and show them
18762 greyed out, instead of only later giving "not selectable" popup error.
18764 Defaults to @samp{()}.
18767 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
18768 Host allowed in URLAUTH URLs sent by client. "*" allows all.
18769 Defaults to @samp{""}.
18773 Whew! Lots of configuration options. The nice thing about it though is
18774 that Guix has a complete interface to Dovecot's configuration
18775 language. This allows not only a nice way to declare configurations,
18776 but also offers reflective capabilities as well: users can write code to
18777 inspect and transform configurations from within Scheme.
18779 However, it could be that you just want to get a @code{dovecot.conf} up
18780 and running. In that case, you can pass an
18781 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
18782 @code{dovecot-service}. As its name indicates, an opaque configuration
18783 does not have easy reflective capabilities.
18785 Available @code{opaque-dovecot-configuration} fields are:
18787 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
18788 The dovecot package.
18791 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
18792 The contents of the @code{dovecot.conf}, as a string.
18795 For example, if your @code{dovecot.conf} is just the empty string, you
18796 could instantiate a dovecot service like this:
18799 (dovecot-service #:config
18800 (opaque-dovecot-configuration
18804 @subsubheading OpenSMTPD Service
18806 @deffn {Scheme Variable} opensmtpd-service-type
18807 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
18808 service, whose value should be an @code{opensmtpd-configuration} object
18809 as in this example:
18812 (service opensmtpd-service-type
18813 (opensmtpd-configuration
18814 (config-file (local-file "./my-smtpd.conf"))))
18818 @deftp {Data Type} opensmtpd-configuration
18819 Data type representing the configuration of opensmtpd.
18822 @item @code{package} (default: @var{opensmtpd})
18823 Package object of the OpenSMTPD SMTP server.
18825 @item @code{config-file} (default: @code{%default-opensmtpd-file})
18826 File-like object of the OpenSMTPD configuration file to use. By default
18827 it listens on the loopback network interface, and allows for mail from
18828 users and daemons on the local machine, as well as permitting email to
18829 remote servers. Run @command{man smtpd.conf} for more information.
18834 @subsubheading Exim Service
18836 @cindex mail transfer agent (MTA)
18837 @cindex MTA (mail transfer agent)
18840 @deffn {Scheme Variable} exim-service-type
18841 This is the type of the @uref{https://exim.org, Exim} mail transfer
18842 agent (MTA), whose value should be an @code{exim-configuration} object
18843 as in this example:
18846 (service exim-service-type
18847 (exim-configuration
18848 (config-file (local-file "./my-exim.conf"))))
18852 In order to use an @code{exim-service-type} service you must also have a
18853 @code{mail-aliases-service-type} service present in your
18854 @code{operating-system} (even if it has no aliases).
18856 @deftp {Data Type} exim-configuration
18857 Data type representing the configuration of exim.
18860 @item @code{package} (default: @var{exim})
18861 Package object of the Exim server.
18863 @item @code{config-file} (default: @code{#f})
18864 File-like object of the Exim configuration file to use. If its value is
18865 @code{#f} then use the default configuration file from the package
18866 provided in @code{package}. The resulting configuration file is loaded
18867 after setting the @code{exim_user} and @code{exim_group} configuration
18873 @subsubheading Getmail service
18878 @deffn {Scheme Variable} getmail-service-type
18879 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
18880 mail retriever, whose value should be an @code{getmail-configuration}.
18883 Available @code{getmail-configuration} fields are:
18885 @deftypevr {@code{getmail-configuration} parameter} symbol name
18886 A symbol to identify the getmail service.
18888 Defaults to @samp{"unset"}.
18892 @deftypevr {@code{getmail-configuration} parameter} package package
18893 The getmail package to use.
18897 @deftypevr {@code{getmail-configuration} parameter} string user
18898 The user to run getmail as.
18900 Defaults to @samp{"getmail"}.
18904 @deftypevr {@code{getmail-configuration} parameter} string group
18905 The group to run getmail as.
18907 Defaults to @samp{"getmail"}.
18911 @deftypevr {@code{getmail-configuration} parameter} string directory
18912 The getmail directory to use.
18914 Defaults to @samp{"/var/lib/getmail/default"}.
18918 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
18919 The getmail configuration file to use.
18921 Available @code{getmail-configuration-file} fields are:
18923 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
18924 What mail account to retrieve mail from, and how to access that account.
18926 Available @code{getmail-retriever-configuration} fields are:
18928 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
18929 The type of mail retriever to use. Valid values include @samp{passwd}
18932 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
18936 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
18937 Username to login to the mail server with.
18939 Defaults to @samp{unset}.
18943 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
18944 Username to login to the mail server with.
18946 Defaults to @samp{unset}.
18950 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
18951 Port number to connect to.
18953 Defaults to @samp{#f}.
18957 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
18958 Override fields from passwd.
18960 Defaults to @samp{""}.
18964 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
18965 Override fields from passwd.
18967 Defaults to @samp{()}.
18971 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
18972 PEM-formatted key file to use for the TLS negotiation.
18974 Defaults to @samp{""}.
18978 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
18979 PEM-formatted certificate file to use for the TLS negotiation.
18981 Defaults to @samp{""}.
18985 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
18986 CA certificates to use.
18988 Defaults to @samp{""}.
18992 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
18993 Extra retriever parameters.
18995 Defaults to @samp{()}.
19001 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
19002 What to do with retrieved messages.
19004 Available @code{getmail-destination-configuration} fields are:
19006 @deftypevr {@code{getmail-destination-configuration} parameter} string type
19007 The type of mail destination. Valid values include @samp{Maildir},
19008 @samp{Mboxrd} and @samp{MDA_external}.
19010 Defaults to @samp{unset}.
19014 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
19015 The path option for the mail destination. The behaviour depends on the
19018 Defaults to @samp{""}.
19022 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
19023 Extra destination parameters
19025 Defaults to @samp{()}.
19031 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
19034 Available @code{getmail-options-configuration} fields are:
19036 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
19037 If set to @samp{0}, getmail will only print warnings and errors. A
19038 value of @samp{1} means that messages will be printed about retrieving
19039 and deleting messages. If set to @samp{2}, getmail will print messages
19040 about each of it's actions.
19042 Defaults to @samp{1}.
19046 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
19047 If true, getmail will retrieve all available messages. Otherwise it
19048 will only retrieve messages it hasn't seen previously.
19050 Defaults to @samp{#t}.
19054 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
19055 If set to true, messages will be deleted from the server after
19056 retrieving and successfully delivering them. Otherwise, messages will
19057 be left on the server.
19059 Defaults to @samp{#f}.
19063 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
19064 Getmail will delete messages this number of days after seeing them, if
19065 they have been delivered. This means messages will be left on the
19066 server this number of days after delivering them. A value of @samp{0}
19067 disabled this feature.
19069 Defaults to @samp{0}.
19073 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
19074 Delete messages larger than this of bytes after retrieving them, even if
19075 the delete and delete-after options are disabled. A value of @samp{0}
19076 disables this feature.
19078 Defaults to @samp{0}.
19082 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
19083 Retrieve messages totalling up to this number of bytes before closing
19084 the session with the server. A value of @samp{0} disables this feature.
19086 Defaults to @samp{0}.
19090 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
19091 Don't retrieve messages larger than this number of bytes. A value of
19092 @samp{0} disables this feature.
19094 Defaults to @samp{0}.
19098 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
19099 If true, getmail will add a Delivered-To header to messages.
19101 Defaults to @samp{#t}.
19105 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
19106 If set, getmail adds a Received header to the messages.
19108 Defaults to @samp{#t}.
19112 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
19113 Getmail will record a log of its actions to the named file. A value of
19114 @samp{""} disables this feature.
19116 Defaults to @samp{""}.
19120 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
19121 If true, getmail will record a log of its actions using the system
19124 Defaults to @samp{#f}.
19128 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
19129 If true, getmail will log information about messages not retrieved and
19130 the reason for not retrieving them, as well as starting and ending
19133 Defaults to @samp{#f}.
19137 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
19138 Extra options to include.
19140 Defaults to @samp{()}.
19148 @deftypevr {@code{getmail-configuration} parameter} list idle
19149 A list of mailboxes that getmail should wait on the server for new mail
19150 notifications. This depends on the server supporting the IDLE
19153 Defaults to @samp{()}.
19157 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
19158 Environment variables to set for getmail.
19160 Defaults to @samp{()}.
19164 @subsubheading Mail Aliases Service
19166 @cindex email aliases
19167 @cindex aliases, for email addresses
19169 @deffn {Scheme Variable} mail-aliases-service-type
19170 This is the type of the service which provides @code{/etc/aliases},
19171 specifying how to deliver mail to users on this system.
19174 (service mail-aliases-service-type
19175 '(("postmaster" "bob")
19176 ("bob" "bob@@example.com" "bob@@example2.com")))
19180 The configuration for a @code{mail-aliases-service-type} service is an
19181 association list denoting how to deliver mail that comes to this
19182 system. Each entry is of the form @code{(alias addresses ...)}, with
19183 @code{alias} specifying the local alias and @code{addresses} specifying
19184 where to deliver this user's mail.
19186 The aliases aren't required to exist as users on the local system. In
19187 the above example, there doesn't need to be a @code{postmaster} entry in
19188 the @code{operating-system}'s @code{user-accounts} in order to deliver
19189 the @code{postmaster} mail to @code{bob} (which subsequently would
19190 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
19192 @subsubheading GNU Mailutils IMAP4 Daemon
19193 @cindex GNU Mailutils IMAP4 Daemon
19195 @deffn {Scheme Variable} imap4d-service-type
19196 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
19197 mailutils, GNU Mailutils Manual}), whose value should be an
19198 @code{imap4d-configuration} object as in this example:
19201 (service imap4d-service-type
19202 (imap4d-configuration
19203 (config-file (local-file "imap4d.conf"))))
19207 @deftp {Data Type} imap4d-configuration
19208 Data type representing the configuration of @command{imap4d}.
19211 @item @code{package} (default: @code{mailutils})
19212 The package that provides @command{imap4d}.
19214 @item @code{config-file} (default: @code{%default-imap4d-config-file})
19215 File-like object of the configuration file to use, by default it will listen
19216 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
19217 Mailutils Manual}, for details.
19222 @node Messaging Services
19223 @subsection Messaging Services
19228 The @code{(gnu services messaging)} module provides Guix service
19229 definitions for messaging services: currently only Prosody is supported.
19231 @subsubheading Prosody Service
19233 @deffn {Scheme Variable} prosody-service-type
19234 This is the type for the @uref{https://prosody.im, Prosody XMPP
19235 communication server}. Its value must be a @code{prosody-configuration}
19236 record as in this example:
19239 (service prosody-service-type
19240 (prosody-configuration
19241 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
19244 (int-component-configuration
19245 (hostname "conference.example.net")
19247 (mod-muc (mod-muc-configuration)))))
19250 (virtualhost-configuration
19251 (domain "example.net"))))))
19254 See below for details about @code{prosody-configuration}.
19258 By default, Prosody does not need much configuration. Only one
19259 @code{virtualhosts} field is needed: it specifies the domain you wish
19262 You can perform various sanity checks on the generated configuration
19263 with the @code{prosodyctl check} command.
19265 Prosodyctl will also help you to import certificates from the
19266 @code{letsencrypt} directory so that the @code{prosody} user can access
19267 them. See @url{https://prosody.im/doc/letsencrypt}.
19270 prosodyctl --root cert import /etc/letsencrypt/live
19273 The available configuration parameters follow. Each parameter
19274 definition is preceded by its type; for example, @samp{string-list foo}
19275 indicates that the @code{foo} parameter should be specified as a list of
19276 strings. Types starting with @code{maybe-} denote parameters that won't
19277 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
19279 There is also a way to specify the configuration as a string, if you
19280 have an old @code{prosody.cfg.lua} file that you want to port over from
19281 some other system; see the end for more details.
19283 The @code{file-object} type designates either a file-like object
19284 (@pxref{G-Expressions, file-like objects}) or a file name.
19286 @c The following documentation was initially generated by
19287 @c (generate-documentation) in (gnu services messaging). Manually maintained
19288 @c documentation is better, so we shouldn't hesitate to edit below as
19289 @c needed. However if the change you want to make to this documentation
19290 @c can be done in an automated way, it's probably easier to change
19291 @c (generate-documentation) than to make it below and have to deal with
19292 @c the churn as Prosody updates.
19294 Available @code{prosody-configuration} fields are:
19296 @deftypevr {@code{prosody-configuration} parameter} package prosody
19297 The Prosody package.
19300 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
19301 Location of the Prosody data storage directory. See
19302 @url{https://prosody.im/doc/configure}.
19303 Defaults to @samp{"/var/lib/prosody"}.
19306 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
19307 Additional plugin directories. They are searched in all the specified
19308 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
19309 Defaults to @samp{()}.
19312 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
19313 Every virtual host and component needs a certificate so that clients and
19314 servers can securely verify its identity. Prosody will automatically load
19315 certificates/keys from the directory specified here.
19316 Defaults to @samp{"/etc/prosody/certs"}.
19319 @deftypevr {@code{prosody-configuration} parameter} string-list admins
19320 This is a list of accounts that are admins for the server. Note that you
19321 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
19322 @url{https://prosody.im/doc/creating_accounts}.
19323 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
19324 Defaults to @samp{()}.
19327 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
19328 Enable use of libevent for better performance under high load. See
19329 @url{https://prosody.im/doc/libevent}.
19330 Defaults to @samp{#f}.
19333 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
19334 This is the list of modules Prosody will load on startup. It looks for
19335 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
19336 Documentation on modules can be found at:
19337 @url{https://prosody.im/doc/modules}.
19338 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
19341 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
19342 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
19343 should you want to disable them then add them to this list.
19344 Defaults to @samp{()}.
19347 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
19348 Path to a text file where the shared groups are defined. If this path is
19349 empty then @samp{mod_groups} does nothing. See
19350 @url{https://prosody.im/doc/modules/mod_groups}.
19351 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
19354 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
19355 Disable account creation by default, for security. See
19356 @url{https://prosody.im/doc/creating_accounts}.
19357 Defaults to @samp{#f}.
19360 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
19361 These are the SSL/TLS-related settings. Most of them are disabled so to
19362 use Prosody's defaults. If you do not completely understand these options, do
19363 not add them to your config, it is easy to lower the security of your server
19364 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
19366 Available @code{ssl-configuration} fields are:
19368 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
19369 This determines what handshake to use.
19372 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
19373 Path to your private key file.
19376 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
19377 Path to your certificate file.
19380 @deftypevr {@code{ssl-configuration} parameter} file-object capath
19381 Path to directory containing root certificates that you wish Prosody to
19382 trust when verifying the certificates of remote servers.
19383 Defaults to @samp{"/etc/ssl/certs"}.
19386 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
19387 Path to a file containing root certificates that you wish Prosody to trust.
19388 Similar to @code{capath} but with all certificates concatenated together.
19391 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
19392 A list of verification options (these mostly map to OpenSSL's
19393 @code{set_verify()} flags).
19396 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
19397 A list of general options relating to SSL/TLS. These map to OpenSSL's
19398 @code{set_options()}. For a full list of options available in LuaSec, see the
19402 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
19403 How long a chain of certificate authorities to check when looking for a
19404 trusted root certificate.
19407 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
19408 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
19409 clients, and in what order.
19412 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
19413 A path to a file containing parameters for Diffie-Hellman key exchange. You
19414 can create such a file with:
19415 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
19418 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
19419 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
19420 @samp{"secp384r1"}.
19423 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
19424 A list of ``extra'' verification options.
19427 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
19428 Password for encrypted private keys.
19433 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
19434 Whether to force all client-to-server connections to be encrypted or not.
19435 See @url{https://prosody.im/doc/modules/mod_tls}.
19436 Defaults to @samp{#f}.
19439 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
19440 Set of mechanisms that will never be offered. See
19441 @url{https://prosody.im/doc/modules/mod_saslauth}.
19442 Defaults to @samp{("DIGEST-MD5")}.
19445 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
19446 Whether to force all server-to-server connections to be encrypted or not.
19447 See @url{https://prosody.im/doc/modules/mod_tls}.
19448 Defaults to @samp{#f}.
19451 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
19452 Whether to require encryption and certificate authentication. This
19453 provides ideal security, but requires servers you communicate with to support
19454 encryption AND present valid, trusted certificates. See
19455 @url{https://prosody.im/doc/s2s#security}.
19456 Defaults to @samp{#f}.
19459 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
19460 Many servers don't support encryption or have invalid or self-signed
19461 certificates. You can list domains here that will not be required to
19462 authenticate using certificates. They will be authenticated using DNS. See
19463 @url{https://prosody.im/doc/s2s#security}.
19464 Defaults to @samp{()}.
19467 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
19468 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
19469 valid certificates for some domains by specifying a list here. See
19470 @url{https://prosody.im/doc/s2s#security}.
19471 Defaults to @samp{()}.
19474 @deftypevr {@code{prosody-configuration} parameter} string authentication
19475 Select the authentication backend to use. The default provider stores
19476 passwords in plaintext and uses Prosody's configured data storage to store the
19477 authentication data. If you do not trust your server please see
19478 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
19479 about using the hashed backend. See also
19480 @url{https://prosody.im/doc/authentication}
19481 Defaults to @samp{"internal_plain"}.
19484 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
19485 Set logging options. Advanced logging configuration is not yet supported
19486 by the Prosody service. See @url{https://prosody.im/doc/logging}.
19487 Defaults to @samp{"*syslog"}.
19490 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
19491 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
19492 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
19495 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
19496 Maximum allowed size of the HTTP body (in bytes).
19499 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
19500 Some modules expose their own URL in various ways. This URL is built
19501 from the protocol, host and port used. If Prosody sits behind a proxy, the
19502 public URL will be @code{http-external-url} instead. See
19503 @url{https://prosody.im/doc/http#external_url}.
19506 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
19507 A host in Prosody is a domain on which user accounts can be created. For
19508 example if you want your users to have addresses like
19509 @samp{"john.smith@@example.com"} then you need to add a host
19510 @samp{"example.com"}. All options in this list will apply only to this host.
19512 Note: the name @emph{virtual} host is used in configuration to avoid confusion with
19513 the actual physical host that Prosody is installed on. A single Prosody
19514 instance can serve many domains, each one defined as a VirtualHost entry in
19515 Prosody's configuration. Conversely a server that hosts a single domain would
19516 have just one VirtualHost entry.
19518 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
19520 Available @code{virtualhost-configuration} fields are:
19522 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:
19523 @deftypevr {@code{virtualhost-configuration} parameter} string domain
19524 Domain you wish Prosody to serve.
19529 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
19530 Components are extra services on a server which are available to clients,
19531 usually on a subdomain of the main server (such as
19532 @samp{"mycomponent.example.com"}). Example components might be chatroom
19533 servers, user directories, or gateways to other protocols.
19535 Internal components are implemented with Prosody-specific plugins. To add an
19536 internal component, you simply fill the hostname field, and the plugin you wish
19537 to use for the component.
19539 See @url{https://prosody.im/doc/components}.
19540 Defaults to @samp{()}.
19542 Available @code{int-component-configuration} fields are:
19544 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:
19545 @deftypevr {@code{int-component-configuration} parameter} string hostname
19546 Hostname of the component.
19549 @deftypevr {@code{int-component-configuration} parameter} string plugin
19550 Plugin you wish to use for the component.
19553 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
19554 Multi-user chat (MUC) is Prosody's module for allowing you to create
19555 hosted chatrooms/conferences for XMPP users.
19557 General information on setting up and using multi-user chatrooms can be found
19558 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
19559 which you should read if you are new to XMPP chatrooms.
19561 See also @url{https://prosody.im/doc/modules/mod_muc}.
19563 Available @code{mod-muc-configuration} fields are:
19565 @deftypevr {@code{mod-muc-configuration} parameter} string name
19566 The name to return in service discovery responses.
19567 Defaults to @samp{"Prosody Chatrooms"}.
19570 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
19571 If @samp{#t}, this will only allow admins to create new chatrooms.
19572 Otherwise anyone can create a room. The value @samp{"local"} restricts room
19573 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
19574 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
19575 restricts to service administrators only.
19576 Defaults to @samp{#f}.
19579 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
19580 Maximum number of history messages that will be sent to the member that has
19581 just joined the room.
19582 Defaults to @samp{20}.
19589 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
19590 External components use XEP-0114, which most standalone components
19591 support. To add an external component, you simply fill the hostname field. See
19592 @url{https://prosody.im/doc/components}.
19593 Defaults to @samp{()}.
19595 Available @code{ext-component-configuration} fields are:
19597 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:
19598 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
19599 Password which the component will use to log in.
19602 @deftypevr {@code{ext-component-configuration} parameter} string hostname
19603 Hostname of the component.
19608 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
19609 Port(s) Prosody listens on for component connections.
19610 Defaults to @samp{(5347)}.
19613 @deftypevr {@code{prosody-configuration} parameter} string component-interface
19614 Interface Prosody listens on for component connections.
19615 Defaults to @samp{"127.0.0.1"}.
19618 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
19619 Raw content that will be added to the configuration file.
19622 It could be that you just want to get a @code{prosody.cfg.lua}
19623 up and running. In that case, you can pass an
19624 @code{opaque-prosody-configuration} record as the value of
19625 @code{prosody-service-type}. As its name indicates, an opaque configuration
19626 does not have easy reflective capabilities.
19627 Available @code{opaque-prosody-configuration} fields are:
19629 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
19630 The prosody package.
19633 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
19634 The contents of the @code{prosody.cfg.lua} to use.
19637 For example, if your @code{prosody.cfg.lua} is just the empty
19638 string, you could instantiate a prosody service like this:
19641 (service prosody-service-type
19642 (opaque-prosody-configuration
19643 (prosody.cfg.lua "")))
19646 @c end of Prosody auto-generated documentation
19648 @subsubheading BitlBee Service
19650 @cindex IRC (Internet Relay Chat)
19651 @cindex IRC gateway
19652 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
19653 interface to a variety of messaging protocols such as XMPP.
19655 @defvr {Scheme Variable} bitlbee-service-type
19656 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
19657 gateway daemon. Its value is a @code{bitlbee-configuration} (see
19660 To have BitlBee listen on port 6667 on localhost, add this line to your
19664 (service bitlbee-service-type)
19668 @deftp {Data Type} bitlbee-configuration
19669 This is the configuration for BitlBee, with the following fields:
19672 @item @code{interface} (default: @code{"127.0.0.1"})
19673 @itemx @code{port} (default: @code{6667})
19674 Listen on the network interface corresponding to the IP address
19675 specified in @var{interface}, on @var{port}.
19677 When @var{interface} is @code{127.0.0.1}, only local clients can
19678 connect; when it is @code{0.0.0.0}, connections can come from any
19679 networking interface.
19681 @item @code{bitlbee} (default: @code{bitlbee})
19682 The BitlBee package to use.
19684 @item @code{plugins} (default: @code{'()})
19685 List of plugin packages to use---e.g., @code{bitlbee-discord}.
19687 @item @code{extra-settings} (default: @code{""})
19688 Configuration snippet added as-is to the BitlBee configuration file.
19692 @subsubheading Quassel Service
19694 @cindex IRC (Internet Relay Chat)
19695 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
19696 meaning that one or more clients can attach to and detach from the
19699 @defvr {Scheme Variable} quassel-service-type
19700 This is the service type for the @url{https://quassel-irc.org/,Quassel}
19701 IRC backend daemon. Its value is a @code{quassel-configuration}
19705 @deftp {Data Type} quassel-configuration
19706 This is the configuration for Quassel, with the following fields:
19709 @item @code{quassel} (default: @code{quassel})
19710 The Quassel package to use.
19712 @item @code{interface} (default: @code{"::,0.0.0.0"})
19713 @item @code{port} (default: @code{4242})
19714 Listen on the network interface(s) corresponding to the IPv4 or IPv6
19715 interfaces specified in the comma delimited @var{interface}, on
19718 @item @code{loglevel} (default: @code{"Info"})
19719 The level of logging desired. Accepted values are Debug, Info, Warning
19724 @node Telephony Services
19725 @subsection Telephony Services
19727 @cindex Murmur (VoIP server)
19728 @cindex VoIP server
19729 This section describes how to set up and run a Murmur server. Murmur is
19730 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
19733 @deftp {Data Type} murmur-configuration
19734 The service type for the Murmur server. An example configuration can
19738 (service murmur-service-type
19739 (murmur-configuration
19741 "Welcome to this Mumble server running on Guix!")
19742 (cert-required? #t) ;disallow text password logins
19743 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
19744 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
19747 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
19748 password with the command that is printed during the activation phase.
19750 It is recommended to register a normal Mumble user account
19751 and grant it admin or moderator rights.
19752 You can use the @code{mumble} client to
19753 login as new normal user, register yourself, and log out.
19754 For the next step login with the name @code{SuperUser} use
19755 the @code{SuperUser} password that you set previously,
19756 and grant your newly registered mumble user administrator or moderator
19757 rights and create some channels.
19759 Available @code{murmur-configuration} fields are:
19762 @item @code{package} (default: @code{mumble})
19763 Package that contains @code{bin/murmurd}.
19765 @item @code{user} (default: @code{"murmur"})
19766 User who will run the Murmur server.
19768 @item @code{group} (default: @code{"murmur"})
19769 Group of the user who will run the murmur server.
19771 @item @code{port} (default: @code{64738})
19772 Port on which the server will listen.
19774 @item @code{welcome-text} (default: @code{""})
19775 Welcome text sent to clients when they connect.
19777 @item @code{server-password} (default: @code{""})
19778 Password the clients have to enter in order to connect.
19780 @item @code{max-users} (default: @code{100})
19781 Maximum of users that can be connected to the server at once.
19783 @item @code{max-user-bandwidth} (default: @code{#f})
19784 Maximum voice traffic a user can send per second.
19786 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
19787 File name of the sqlite database.
19788 The service's user will become the owner of the directory.
19790 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
19791 File name of the log file.
19792 The service's user will become the owner of the directory.
19794 @item @code{autoban-attempts} (default: @code{10})
19795 Maximum number of logins a user can make in @code{autoban-timeframe}
19796 without getting auto banned for @code{autoban-time}.
19798 @item @code{autoban-timeframe} (default: @code{120})
19799 Timeframe for autoban in seconds.
19801 @item @code{autoban-time} (default: @code{300})
19802 Amount of time in seconds for which a client gets banned
19803 when violating the autoban limits.
19805 @item @code{opus-threshold} (default: @code{100})
19806 Percentage of clients that need to support opus
19807 before switching over to opus audio codec.
19809 @item @code{channel-nesting-limit} (default: @code{10})
19810 How deep channels can be nested at maximum.
19812 @item @code{channelname-regex} (default: @code{#f})
19813 A string in form of a Qt regular expression that channel names must conform to.
19815 @item @code{username-regex} (default: @code{#f})
19816 A string in form of a Qt regular expression that user names must conform to.
19818 @item @code{text-message-length} (default: @code{5000})
19819 Maximum size in bytes that a user can send in one text chat message.
19821 @item @code{image-message-length} (default: @code{(* 128 1024)})
19822 Maximum size in bytes that a user can send in one image message.
19824 @item @code{cert-required?} (default: @code{#f})
19825 If it is set to @code{#t} clients that use weak password authentication
19826 will not be accepted. Users must have completed the certificate wizard to join.
19828 @item @code{remember-channel?} (default: @code{#f})
19829 Should murmur remember the last channel each user was in when they disconnected
19830 and put them into the remembered channel when they rejoin.
19832 @item @code{allow-html?} (default: @code{#f})
19833 Should html be allowed in text messages, user comments, and channel descriptions.
19835 @item @code{allow-ping?} (default: @code{#f})
19836 Setting to true exposes the current user count, the maximum user count, and
19837 the server's maximum bandwidth per client to unauthenticated users. In the
19838 Mumble client, this information is shown in the Connect dialog.
19840 Disabling this setting will prevent public listing of the server.
19842 @item @code{bonjour?} (default: @code{#f})
19843 Should the server advertise itself in the local network through the bonjour protocol.
19845 @item @code{send-version?} (default: @code{#f})
19846 Should the murmur server version be exposed in ping requests.
19848 @item @code{log-days} (default: @code{31})
19849 Murmur also stores logs in the database, which are accessible via RPC.
19850 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
19851 or -1 to disable logging to the database.
19853 @item @code{obfuscate-ips?} (default: @code{#t})
19854 Should logged ips be obfuscated to protect the privacy of users.
19856 @item @code{ssl-cert} (default: @code{#f})
19857 File name of the SSL/TLS certificate used for encrypted connections.
19860 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
19862 @item @code{ssl-key} (default: @code{#f})
19863 Filepath to the ssl private key used for encrypted connections.
19865 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
19868 @item @code{ssl-dh-params} (default: @code{#f})
19869 File name of a PEM-encoded file with Diffie-Hellman parameters
19870 for the SSL/TLS encryption. Alternatively you set it to
19871 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
19872 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
19874 @item @code{ssl-ciphers} (default: @code{#f})
19875 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
19878 This option is specified using
19879 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
19880 OpenSSL cipher list notation}.
19882 It is recommended that you try your cipher string using 'openssl ciphers <string>'
19883 before setting it here, to get a feel for which cipher suites you will get.
19884 After setting this option, it is recommend that you inspect your Murmur log
19885 to ensure that Murmur is using the cipher suites that you expected it to.
19887 Note: Changing this option may impact the backwards compatibility of your
19888 Murmur server, and can remove the ability for older Mumble clients to be able
19891 @item @code{public-registration} (default: @code{#f})
19892 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
19894 You can optionally register your server in the public server list that the
19895 @code{mumble} client shows on startup.
19896 You cannot register your server if you have set a @code{server-password},
19897 or set @code{allow-ping} to @code{#f}.
19899 It might take a few hours until it shows up in the public list.
19901 @item @code{file} (default: @code{#f})
19902 Optional alternative override for this configuration.
19906 @deftp {Data Type} murmur-public-registration-configuration
19907 Configuration for public registration of a murmur service.
19911 This is a display name for your server. Not to be confused with the hostname.
19913 @item @code{password}
19914 A password to identify your registration.
19915 Subsequent updates will need the same password. Don't lose your password.
19918 This should be a @code{http://} or @code{https://} link to your web
19921 @item @code{hostname} (default: @code{#f})
19922 By default your server will be listed by its IP address.
19923 If it is set your server will be linked by this host name instead.
19929 @node Monitoring Services
19930 @subsection Monitoring Services
19932 @subsubheading Tailon Service
19934 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
19935 viewing and searching log files.
19937 The following example will configure the service with default values.
19938 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
19941 (service tailon-service-type)
19944 The following example customises more of the Tailon configuration,
19945 adding @command{sed} to the list of allowed commands.
19948 (service tailon-service-type
19949 (tailon-configuration
19951 (tailon-configuration-file
19952 (allowed-commands '("tail" "grep" "awk" "sed"))))))
19956 @deftp {Data Type} tailon-configuration
19957 Data type representing the configuration of Tailon.
19958 This type has the following parameters:
19961 @item @code{config-file} (default: @code{(tailon-configuration-file)})
19962 The configuration file to use for Tailon. This can be set to a
19963 @dfn{tailon-configuration-file} record value, or any gexp
19964 (@pxref{G-Expressions}).
19966 For example, to instead use a local file, the @code{local-file} function
19970 (service tailon-service-type
19971 (tailon-configuration
19972 (config-file (local-file "./my-tailon.conf"))))
19975 @item @code{package} (default: @code{tailon})
19976 The tailon package to use.
19981 @deftp {Data Type} tailon-configuration-file
19982 Data type representing the configuration options for Tailon.
19983 This type has the following parameters:
19986 @item @code{files} (default: @code{(list "/var/log")})
19987 List of files to display. The list can include strings for a single file
19988 or directory, or a list, where the first item is the name of a
19989 subsection, and the remaining items are the files or directories in that
19992 @item @code{bind} (default: @code{"localhost:8080"})
19993 Address and port to which Tailon should bind on.
19995 @item @code{relative-root} (default: @code{#f})
19996 URL path to use for Tailon, set to @code{#f} to not use a path.
19998 @item @code{allow-transfers?} (default: @code{#t})
19999 Allow downloading the log files in the web interface.
20001 @item @code{follow-names?} (default: @code{#t})
20002 Allow tailing of not-yet existent files.
20004 @item @code{tail-lines} (default: @code{200})
20005 Number of lines to read initially from each file.
20007 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
20008 Commands to allow running. By default, @code{sed} is disabled.
20010 @item @code{debug?} (default: @code{#f})
20011 Set @code{debug?} to @code{#t} to show debug messages.
20013 @item @code{wrap-lines} (default: @code{#t})
20014 Initial line wrapping state in the web interface. Set to @code{#t} to
20015 initially wrap lines (the default), or to @code{#f} to initially not
20018 @item @code{http-auth} (default: @code{#f})
20019 HTTP authentication type to use. Set to @code{#f} to disable
20020 authentication (the default). Supported values are @code{"digest"} or
20023 @item @code{users} (default: @code{#f})
20024 If HTTP authentication is enabled (see @code{http-auth}), access will be
20025 restricted to the credentials provided here. To configure users, use a
20026 list of pairs, where the first element of the pair is the username, and
20027 the 2nd element of the pair is the password.
20030 (tailon-configuration-file
20031 (http-auth "basic")
20032 (users '(("user1" . "password1")
20033 ("user2" . "password2"))))
20040 @subsubheading Darkstat Service
20042 Darkstat is a packet sniffer that captures network traffic, calculates
20043 statistics about usage, and serves reports over HTTP.
20045 @defvar {Scheme Variable} darkstat-service-type
20046 This is the service type for the
20047 @uref{https://unix4lyfe.org/darkstat/, darkstat}
20048 service, its value must be a @code{darkstat-configuration} record as in
20052 (service darkstat-service-type
20053 (darkstat-configuration
20054 (interface "eno1")))
20058 @deftp {Data Type} darkstat-configuration
20059 Data type representing the configuration of @command{darkstat}.
20062 @item @code{package} (default: @code{darkstat})
20063 The darkstat package to use.
20065 @item @code{interface}
20066 Capture traffic on the specified network interface.
20068 @item @code{port} (default: @code{"667"})
20069 Bind the web interface to the specified port.
20071 @item @code{bind-address} (default: @code{"127.0.0.1"})
20072 Bind the web interface to the specified address.
20074 @item @code{base} (default: @code{"/"})
20075 Specify the path of the base URL. This can be useful if
20076 @command{darkstat} is accessed via a reverse proxy.
20081 @subsubheading Prometheus Node Exporter Service
20083 @cindex prometheus-node-exporter
20084 The Prometheus ``node exporter'' makes hardware and operating system statistics
20085 provided by the Linux kernel available for the Prometheus monitoring system.
20086 This service should be deployed on all physical nodes and virtual machines,
20087 where monitoring these statistics is desirable.
20089 @defvar {Scheme variable} prometheus-node-exporter-service-type
20090 This is the service type for the
20091 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
20092 service, its value must be a @code{prometheus-node-exporter-configuration}
20093 record as in this example:
20096 (service prometheus-node-exporter-service-type
20097 (prometheus-node-exporter-configuration
20098 (web-listen-address ":9100")))
20102 @deftp {Data Type} prometheus-node-exporter-configuration
20103 Data type representing the configuration of @command{node_exporter}.
20106 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
20107 The prometheus-node-exporter package to use.
20109 @item @code{web-listen-address} (default: @code{":9100"})
20110 Bind the web interface to the specified address.
20115 @subsubheading Zabbix server
20116 @cindex zabbix zabbix-server
20117 Zabbix provides monitoring metrics, among others network utilization, CPU load
20118 and disk space consumption:
20121 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
20122 @item Auto-discovery of servers and network devices and interfaces.
20123 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
20124 @item Distributed monitoring with centralized web administration.
20125 @item Native high performance agents.
20126 @item SLA, and ITIL KPI metrics on reporting.
20127 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
20128 @item Remote command execution through Zabbix proxies.
20131 @c %start of fragment
20133 Available @code{zabbix-server-configuration} fields are:
20135 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
20136 The zabbix-server package.
20140 @deftypevr {@code{zabbix-server-configuration} parameter} string user
20141 User who will run the Zabbix server.
20143 Defaults to @samp{"zabbix"}.
20147 @deftypevr {@code{zabbix-server-configuration} parameter} group group
20148 Group who will run the Zabbix server.
20150 Defaults to @samp{"zabbix"}.
20154 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
20155 Database host name.
20157 Defaults to @samp{"127.0.0.1"}.
20161 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
20164 Defaults to @samp{"zabbix"}.
20168 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
20171 Defaults to @samp{"zabbix"}.
20175 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
20176 Database password. Please, use @code{include-files} with
20177 @code{DBPassword=SECRET} inside a specified file instead.
20179 Defaults to @samp{""}.
20183 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
20186 Defaults to @samp{5432}.
20190 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
20191 Specifies where log messages are written to:
20195 @code{system} - syslog.
20198 @code{file} - file specified with @code{log-file} parameter.
20201 @code{console} - standard output.
20205 Defaults to @samp{""}.
20209 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
20210 Log file name for @code{log-type} @code{file} parameter.
20212 Defaults to @samp{"/var/log/zabbix/server.log"}.
20216 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
20219 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
20223 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
20224 The location of certificate authority (CA) files for SSL server
20225 certificate verification.
20227 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
20231 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
20232 Location of SSL client certificates.
20234 Defaults to @samp{"/etc/ssl/certs"}.
20238 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
20239 Extra options will be appended to Zabbix server configuration file.
20241 Defaults to @samp{""}.
20245 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
20246 You may include individual files or all files in a directory in the
20247 configuration file.
20249 Defaults to @samp{()}.
20253 @c %end of fragment
20255 @subsubheading Zabbix agent
20256 @cindex zabbix zabbix-agent
20258 Zabbix agent gathers information for Zabbix server.
20260 @c %start of fragment
20262 Available @code{zabbix-agent-configuration} fields are:
20264 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
20265 The zabbix-agent package.
20269 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
20270 User who will run the Zabbix agent.
20272 Defaults to @samp{"zabbix"}.
20276 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
20277 Group who will run the Zabbix agent.
20279 Defaults to @samp{"zabbix"}.
20283 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
20284 Unique, case sensitive hostname which is required for active checks and
20285 must match hostname as configured on the server.
20287 Defaults to @samp{"Zabbix server"}.
20291 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
20292 Specifies where log messages are written to:
20296 @code{system} - syslog.
20299 @code{file} - file specified with @code{log-file} parameter.
20302 @code{console} - standard output.
20306 Defaults to @samp{""}.
20310 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
20311 Log file name for @code{log-type} @code{file} parameter.
20313 Defaults to @samp{"/var/log/zabbix/agent.log"}.
20317 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
20320 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
20324 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
20325 List of IP addresses, optionally in CIDR notation, or hostnames of
20326 Zabbix servers and Zabbix proxies. Incoming connections will be
20327 accepted only from the hosts listed here.
20329 Defaults to @samp{("127.0.0.1")}.
20333 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
20334 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
20335 proxies for active checks. If port is not specified, default port is
20336 used. If this parameter is not specified, active checks are disabled.
20338 Defaults to @samp{("127.0.0.1")}.
20342 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
20343 Extra options will be appended to Zabbix server configuration file.
20345 Defaults to @samp{""}.
20349 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
20350 You may include individual files or all files in a directory in the
20351 configuration file.
20353 Defaults to @samp{()}.
20357 @c %end of fragment
20359 @subsubheading Zabbix front-end
20360 @cindex zabbix zabbix-front-end
20362 This service provides a WEB interface to Zabbix server.
20364 @c %start of fragment
20366 Available @code{zabbix-front-end-configuration} fields are:
20368 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
20369 NGINX configuration.
20373 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
20374 Database host name.
20376 Defaults to @samp{"localhost"}.
20380 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
20383 Defaults to @samp{5432}.
20387 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
20390 Defaults to @samp{"zabbix"}.
20394 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
20397 Defaults to @samp{"zabbix"}.
20401 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
20402 Database password. Please, use @code{db-secret-file} instead.
20404 Defaults to @samp{""}.
20408 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
20409 Secret file which will be appended to @file{zabbix.conf.php} file. This
20410 file contains credentials for use by Zabbix front-end. You are expected
20411 to create it manually.
20413 Defaults to @samp{""}.
20417 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
20418 Zabbix server hostname.
20420 Defaults to @samp{"localhost"}.
20424 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
20425 Zabbix server port.
20427 Defaults to @samp{10051}.
20432 @c %end of fragment
20434 @node Kerberos Services
20435 @subsection Kerberos Services
20438 The @code{(gnu services kerberos)} module provides services relating to
20439 the authentication protocol @dfn{Kerberos}.
20441 @subsubheading Krb5 Service
20443 Programs using a Kerberos client library normally
20444 expect a configuration file in @file{/etc/krb5.conf}.
20445 This service generates such a file from a definition provided in the
20446 operating system declaration.
20447 It does not cause any daemon to be started.
20449 No ``keytab'' files are provided by this service---you must explicitly create them.
20450 This service is known to work with the MIT client library, @code{mit-krb5}.
20451 Other implementations have not been tested.
20453 @defvr {Scheme Variable} krb5-service-type
20454 A service type for Kerberos 5 clients.
20458 Here is an example of its use:
20460 (service krb5-service-type
20461 (krb5-configuration
20462 (default-realm "EXAMPLE.COM")
20463 (allow-weak-crypto? #t)
20466 (name "EXAMPLE.COM")
20467 (admin-server "groucho.example.com")
20468 (kdc "karl.example.com"))
20471 (admin-server "kerb-admin.argrx.edu")
20472 (kdc "keys.argrx.edu"))))))
20476 This example provides a Kerberos@tie{}5 client configuration which:
20478 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
20479 of which have distinct administration servers and key distribution centers;
20480 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
20481 specified by clients;
20482 @item Accepts services which only support encryption types known to be weak.
20485 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
20486 Only the most commonly used ones are described here.
20487 For a full list, and more detailed explanation of each, see the MIT
20488 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
20492 @deftp {Data Type} krb5-realm
20493 @cindex realm, kerberos
20496 This field is a string identifying the name of the realm.
20497 A common convention is to use the fully qualified DNS name of your organization,
20498 converted to upper case.
20500 @item @code{admin-server}
20501 This field is a string identifying the host where the administration server is
20505 This field is a string identifying the key distribution center
20510 @deftp {Data Type} krb5-configuration
20513 @item @code{allow-weak-crypto?} (default: @code{#f})
20514 If this flag is @code{#t} then services which only offer encryption algorithms
20515 known to be weak will be accepted.
20517 @item @code{default-realm} (default: @code{#f})
20518 This field should be a string identifying the default Kerberos
20519 realm for the client.
20520 You should set this field to the name of your Kerberos realm.
20521 If this value is @code{#f}
20522 then a realm must be specified with every Kerberos principal when invoking programs
20523 such as @command{kinit}.
20525 @item @code{realms}
20526 This should be a non-empty list of @code{krb5-realm} objects, which clients may
20528 Normally, one of them will have a @code{name} field matching the @code{default-realm}
20534 @subsubheading PAM krb5 Service
20537 The @code{pam-krb5} service allows for login authentication and password
20538 management via Kerberos.
20539 You will need this service if you want PAM enabled applications to authenticate
20540 users using Kerberos.
20542 @defvr {Scheme Variable} pam-krb5-service-type
20543 A service type for the Kerberos 5 PAM module.
20546 @deftp {Data Type} pam-krb5-configuration
20547 Data type representing the configuration of the Kerberos 5 PAM module.
20548 This type has the following parameters:
20550 @item @code{pam-krb5} (default: @code{pam-krb5})
20551 The pam-krb5 package to use.
20553 @item @code{minimum-uid} (default: @code{1000})
20554 The smallest user ID for which Kerberos authentications should be attempted.
20555 Local accounts with lower values will silently fail to authenticate.
20560 @node LDAP Services
20561 @subsection LDAP Services
20563 @cindex nslcd, LDAP service
20565 The @code{(gnu services authentication)} module provides the
20566 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
20567 server. In addition to configuring the service itself, you may want to add
20568 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
20569 Switch} for detailed information.
20571 Here is a simple operating system declaration with a default configuration of
20572 the @code{nslcd-service-type} and a Name Service Switch configuration that
20573 consults the @code{ldap} name service last:
20576 (use-service-modules authentication)
20577 (use-modules (gnu system nss))
20583 (service nslcd-service-type)
20584 (service dhcp-client-service-type)
20586 (name-service-switch
20587 (let ((services (list (name-service (name "db"))
20588 (name-service (name "files"))
20589 (name-service (name "ldap")))))
20590 (name-service-switch
20591 (inherit %mdns-host-lookup-nss)
20592 (password services)
20595 (netgroup services)
20596 (gshadow services)))))
20599 @c %start of generated documentation for nslcd-configuration
20601 Available @code{nslcd-configuration} fields are:
20603 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
20604 The @code{nss-pam-ldapd} package to use.
20608 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
20609 The number of threads to start that can handle requests and perform LDAP
20610 queries. Each thread opens a separate connection to the LDAP server.
20611 The default is to start 5 threads.
20613 Defaults to @samp{disabled}.
20617 @deftypevr {@code{nslcd-configuration} parameter} string uid
20618 This specifies the user id with which the daemon should be run.
20620 Defaults to @samp{"nslcd"}.
20624 @deftypevr {@code{nslcd-configuration} parameter} string gid
20625 This specifies the group id with which the daemon should be run.
20627 Defaults to @samp{"nslcd"}.
20631 @deftypevr {@code{nslcd-configuration} parameter} log-option log
20632 This option controls the way logging is done via a list containing
20633 SCHEME and LEVEL. The SCHEME argument may either be the symbols
20634 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
20635 argument is optional and specifies the log level. The log level may be
20636 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
20637 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
20638 specified log level or higher are logged.
20640 Defaults to @samp{("/var/log/nslcd" info)}.
20644 @deftypevr {@code{nslcd-configuration} parameter} list uri
20645 The list of LDAP server URIs. Normally, only the first server will be
20646 used with the following servers as fall-back.
20648 Defaults to @samp{("ldap://localhost:389/")}.
20652 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
20653 The version of the LDAP protocol to use. The default is to use the
20654 maximum version supported by the LDAP library.
20656 Defaults to @samp{disabled}.
20660 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
20661 Specifies the distinguished name with which to bind to the directory
20662 server for lookups. The default is to bind anonymously.
20664 Defaults to @samp{disabled}.
20668 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
20669 Specifies the credentials with which to bind. This option is only
20670 applicable when used with binddn.
20672 Defaults to @samp{disabled}.
20676 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
20677 Specifies the distinguished name to use when the root user tries to
20678 modify a user's password using the PAM module.
20680 Defaults to @samp{disabled}.
20684 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
20685 Specifies the credentials with which to bind if the root user tries to
20686 change a user's password. This option is only applicable when used with
20689 Defaults to @samp{disabled}.
20693 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
20694 Specifies the SASL mechanism to be used when performing SASL
20697 Defaults to @samp{disabled}.
20701 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
20702 Specifies the SASL realm to be used when performing SASL authentication.
20704 Defaults to @samp{disabled}.
20708 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
20709 Specifies the authentication identity to be used when performing SASL
20712 Defaults to @samp{disabled}.
20716 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
20717 Specifies the authorization identity to be used when performing SASL
20720 Defaults to @samp{disabled}.
20724 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
20725 Determines whether the LDAP server host name should be canonicalised. If
20726 this is enabled the LDAP library will do a reverse host name lookup. By
20727 default, it is left up to the LDAP library whether this check is
20730 Defaults to @samp{disabled}.
20734 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
20735 Set the name for the GSS-API Kerberos credentials cache.
20737 Defaults to @samp{disabled}.
20741 @deftypevr {@code{nslcd-configuration} parameter} string base
20742 The directory search base.
20744 Defaults to @samp{"dc=example,dc=com"}.
20748 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
20749 Specifies the search scope (subtree, onelevel, base or children). The
20750 default scope is subtree; base scope is almost never useful for name
20751 service lookups; children scope is not supported on all servers.
20753 Defaults to @samp{(subtree)}.
20757 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
20758 Specifies the policy for dereferencing aliases. The default policy is
20759 to never dereference aliases.
20761 Defaults to @samp{disabled}.
20765 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
20766 Specifies whether automatic referral chasing should be enabled. The
20767 default behaviour is to chase referrals.
20769 Defaults to @samp{disabled}.
20773 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
20774 This option allows for custom attributes to be looked up instead of the
20775 default RFC 2307 attributes. It is a list of maps, each consisting of
20776 the name of a map, the RFC 2307 attribute to match and the query
20777 expression for the attribute as it is available in the directory.
20779 Defaults to @samp{()}.
20783 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
20784 A list of filters consisting of the name of a map to which the filter
20785 applies and an LDAP search filter expression.
20787 Defaults to @samp{()}.
20791 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
20792 Specifies the time limit in seconds to use when connecting to the
20793 directory server. The default value is 10 seconds.
20795 Defaults to @samp{disabled}.
20799 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
20800 Specifies the time limit (in seconds) to wait for a response from the
20801 LDAP server. A value of zero, which is the default, is to wait
20802 indefinitely for searches to be completed.
20804 Defaults to @samp{disabled}.
20808 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
20809 Specifies the period if inactivity (in seconds) after which the con‐
20810 nection to the LDAP server will be closed. The default is not to time
20813 Defaults to @samp{disabled}.
20817 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
20818 Specifies the number of seconds to sleep when connecting to all LDAP
20819 servers fails. By default one second is waited between the first
20820 failure and the first retry.
20822 Defaults to @samp{disabled}.
20826 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
20827 Specifies the time after which the LDAP server is considered to be
20828 permanently unavailable. Once this time is reached retries will be done
20829 only once per this time period. The default value is 10 seconds.
20831 Defaults to @samp{disabled}.
20835 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
20836 Specifies whether to use SSL/TLS or not (the default is not to). If
20837 'start-tls is specified then StartTLS is used rather than raw LDAP over
20840 Defaults to @samp{disabled}.
20844 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
20845 Specifies what checks to perform on a server-supplied certificate. The
20846 meaning of the values is described in the ldap.conf(5) manual page.
20848 Defaults to @samp{disabled}.
20852 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
20853 Specifies the directory containing X.509 certificates for peer authen‐
20854 tication. This parameter is ignored when using GnuTLS.
20856 Defaults to @samp{disabled}.
20860 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
20861 Specifies the path to the X.509 certificate for peer authentication.
20863 Defaults to @samp{disabled}.
20867 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
20868 Specifies the path to an entropy source. This parameter is ignored when
20871 Defaults to @samp{disabled}.
20875 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
20876 Specifies the ciphers to use for TLS as a string.
20878 Defaults to @samp{disabled}.
20882 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
20883 Specifies the path to the file containing the local certificate for
20884 client TLS authentication.
20886 Defaults to @samp{disabled}.
20890 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
20891 Specifies the path to the file containing the private key for client TLS
20894 Defaults to @samp{disabled}.
20898 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
20899 Set this to a number greater than 0 to request paged results from the
20900 LDAP server in accordance with RFC2696. The default (0) is to not
20901 request paged results.
20903 Defaults to @samp{disabled}.
20907 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
20908 This option prevents group membership lookups through LDAP for the
20909 specified users. Alternatively, the value 'all-local may be used. With
20910 that value nslcd builds a full list of non-LDAP users on startup.
20912 Defaults to @samp{disabled}.
20916 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
20917 This option ensures that LDAP users with a numeric user id lower than
20918 the specified value are ignored.
20920 Defaults to @samp{disabled}.
20924 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
20925 This option specifies an offset that is added to all LDAP numeric user
20926 ids. This can be used to avoid user id collisions with local users.
20928 Defaults to @samp{disabled}.
20932 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
20933 This option specifies an offset that is added to all LDAP numeric group
20934 ids. This can be used to avoid user id collisions with local groups.
20936 Defaults to @samp{disabled}.
20940 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
20941 If this option is set, the member attribute of a group may point to
20942 another group. Members of nested groups are also returned in the higher
20943 level group and parent groups are returned when finding groups for a
20944 specific user. The default is not to perform extra searches for nested
20947 Defaults to @samp{disabled}.
20951 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
20952 If this option is set, the group member list is not retrieved when
20953 looking up groups. Lookups for finding which groups a user belongs to
20954 will remain functional so the user will likely still get the correct
20955 groups assigned on login.
20957 Defaults to @samp{disabled}.
20961 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
20962 If this option is set, functions which cause all user/group entries to
20963 be loaded from the directory will not succeed in doing so. This can
20964 dramatically reduce LDAP server load in situations where there are a
20965 great number of users and/or groups. This option is not recommended for
20966 most configurations.
20968 Defaults to @samp{disabled}.
20972 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
20973 This option can be used to specify how user and group names are verified
20974 within the system. This pattern is used to check all user and group
20975 names that are requested and returned from LDAP.
20977 Defaults to @samp{disabled}.
20981 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
20982 This specifies whether or not to perform searches using case-insensitive
20983 matching. Enabling this could open up the system to authorization
20984 bypass vulnerabilities and introduce nscd cache poisoning
20985 vulnerabilities which allow denial of service.
20987 Defaults to @samp{disabled}.
20991 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
20992 This option specifies whether password policy controls are requested and
20993 handled from the LDAP server when performing user authentication.
20995 Defaults to @samp{disabled}.
20999 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
21000 By default nslcd performs an LDAP search with the user's credentials
21001 after BIND (authentication) to ensure that the BIND operation was
21002 successful. The default search is a simple check to see if the user's
21003 DN exists. A search filter can be specified that will be used instead.
21004 It should return at least one entry.
21006 Defaults to @samp{disabled}.
21010 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
21011 This option allows flexible fine tuning of the authorisation check that
21012 should be performed. The search filter specified is executed and if any
21013 entries match, access is granted, otherwise access is denied.
21015 Defaults to @samp{disabled}.
21019 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
21020 If this option is set password modification using pam_ldap will be
21021 denied and the specified message will be presented to the user instead.
21022 The message can be used to direct the user to an alternative means of
21023 changing their password.
21025 Defaults to @samp{disabled}.
21029 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
21030 List of pam service names for which LDAP authentication should suffice.
21032 Defaults to @samp{()}.
21036 @c %end of generated documentation for nslcd-configuration
21040 @subsection Web Services
21045 The @code{(gnu services web)} module provides the Apache HTTP Server,
21046 the nginx web server, and also a fastcgi wrapper daemon.
21048 @subsubheading Apache HTTP Server
21050 @deffn {Scheme Variable} httpd-service-type
21051 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
21052 (@dfn{httpd}). The value for this service type is a
21053 @code{httpd-configuration} record.
21055 A simple example configuration is given below.
21058 (service httpd-service-type
21059 (httpd-configuration
21062 (server-name "www.example.com")
21063 (document-root "/srv/http/www.example.com")))))
21066 Other services can also extend the @code{httpd-service-type} to add to
21070 (simple-service 'www.example.com-server httpd-service-type
21074 (list (string-join '("ServerName www.example.com"
21075 "DocumentRoot /srv/http/www.example.com")
21080 The details for the @code{httpd-configuration}, @code{httpd-module},
21081 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
21084 @deffn {Data Type} httpd-configuration
21085 This data type represents the configuration for the httpd service.
21088 @item @code{package} (default: @code{httpd})
21089 The httpd package to use.
21091 @item @code{pid-file} (default: @code{"/var/run/httpd"})
21092 The pid file used by the shepherd-service.
21094 @item @code{config} (default: @code{(httpd-config-file)})
21095 The configuration file to use with the httpd service. The default value
21096 is a @code{httpd-config-file} record, but this can also be a different
21097 G-expression that generates a file, for example a @code{plain-file}. A
21098 file outside of the store can also be specified through a string.
21103 @deffn {Data Type} httpd-module
21104 This data type represents a module for the httpd service.
21108 The name of the module.
21111 The file for the module. This can be relative to the httpd package being
21112 used, the absolute location of a file, or a G-expression for a file
21113 within the store, for example @code{(file-append mod-wsgi
21114 "/modules/mod_wsgi.so")}.
21119 @defvr {Scheme Variable} %default-httpd-modules
21120 A default list of @code{httpd-module} objects.
21123 @deffn {Data Type} httpd-config-file
21124 This data type represents a configuration file for the httpd service.
21127 @item @code{modules} (default: @code{%default-httpd-modules})
21128 The modules to load. Additional modules can be added here, or loaded by
21129 additional configuration.
21131 For example, in order to handle requests for PHP files, you can use Apache’s
21132 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
21135 (service httpd-service-type
21136 (httpd-configuration
21141 (name "proxy_module")
21142 (file "modules/mod_proxy.so"))
21144 (name "proxy_fcgi_module")
21145 (file "modules/mod_proxy_fcgi.so"))
21146 %default-httpd-modules))
21147 (extra-config (list "\
21148 <FilesMatch \\.php$>
21149 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
21150 </FilesMatch>"))))))
21151 (service php-fpm-service-type
21152 (php-fpm-configuration
21153 (socket "/var/run/php-fpm.sock")
21154 (socket-group "httpd")))
21157 @item @code{server-root} (default: @code{httpd})
21158 The @code{ServerRoot} in the configuration file, defaults to the httpd
21159 package. Directives including @code{Include} and @code{LoadModule} are
21160 taken as relative to the server root.
21162 @item @code{server-name} (default: @code{#f})
21163 The @code{ServerName} in the configuration file, used to specify the
21164 request scheme, hostname and port that the server uses to identify
21167 This doesn't need to be set in the server config, and can be specified
21168 in virtual hosts. The default is @code{#f} to not specify a
21171 @item @code{document-root} (default: @code{"/srv/http"})
21172 The @code{DocumentRoot} from which files will be served.
21174 @item @code{listen} (default: @code{'("80")})
21175 The list of values for the @code{Listen} directives in the config
21176 file. The value should be a list of strings, when each string can
21177 specify the port number to listen on, and optionally the IP address and
21180 @item @code{pid-file} (default: @code{"/var/run/httpd"})
21181 The @code{PidFile} to use. This should match the @code{pid-file} set in
21182 the @code{httpd-configuration} so that the Shepherd service is
21183 configured correctly.
21185 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
21186 The @code{ErrorLog} to which the server will log errors.
21188 @item @code{user} (default: @code{"httpd"})
21189 The @code{User} which the server will answer requests as.
21191 @item @code{group} (default: @code{"httpd"})
21192 The @code{Group} which the server will answer requests as.
21194 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
21195 A flat list of strings and G-expressions which will be added to the end
21196 of the configuration file.
21198 Any values which the service is extended with will be appended to this
21204 @deffn {Data Type} httpd-virtualhost
21205 This data type represents a virtualhost configuration block for the httpd service.
21207 These should be added to the extra-config for the httpd-service.
21210 (simple-service 'www.example.com-server httpd-service-type
21214 (list (string-join '("ServerName www.example.com"
21215 "DocumentRoot /srv/http/www.example.com")
21220 @item @code{addresses-and-ports}
21221 The addresses and ports for the @code{VirtualHost} directive.
21223 @item @code{contents}
21224 The contents of the @code{VirtualHost} directive, this should be a list
21225 of strings and G-expressions.
21230 @subsubheading NGINX
21232 @deffn {Scheme Variable} nginx-service-type
21233 Service type for the @uref{https://nginx.org/,NGinx} web server. The
21234 value for this service type is a @code{<nginx-configuration>} record.
21236 A simple example configuration is given below.
21239 (service nginx-service-type
21240 (nginx-configuration
21242 (list (nginx-server-configuration
21243 (server-name '("www.example.com"))
21244 (root "/srv/http/www.example.com"))))))
21247 In addition to adding server blocks to the service configuration
21248 directly, this service can be extended by other services to add server
21249 blocks, as in this example:
21252 (simple-service 'my-extra-server nginx-service-type
21253 (list (nginx-server-configuration
21254 (root "/srv/http/extra-website")
21255 (try-files (list "$uri" "$uri/index.html")))))
21259 At startup, @command{nginx} has not yet read its configuration file, so
21260 it uses a default file to log error messages. If it fails to load its
21261 configuration file, that is where error messages are logged. After the
21262 configuration file is loaded, the default error log file changes as per
21263 configuration. In our case, startup error messages can be found in
21264 @file{/var/run/nginx/logs/error.log}, and after configuration in
21265 @file{/var/log/nginx/error.log}. The second location can be changed
21266 with the @var{log-directory} configuration option.
21268 @deffn {Data Type} nginx-configuration
21269 This data type represents the configuration for NGinx. Some
21270 configuration can be done through this and the other provided record
21271 types, or alternatively, a config file can be provided.
21274 @item @code{nginx} (default: @code{nginx})
21275 The nginx package to use.
21277 @item @code{log-directory} (default: @code{"/var/log/nginx"})
21278 The directory to which NGinx will write log files.
21280 @item @code{run-directory} (default: @code{"/var/run/nginx"})
21281 The directory in which NGinx will create a pid file, and write temporary
21284 @item @code{server-blocks} (default: @code{'()})
21285 A list of @dfn{server blocks} to create in the generated configuration
21286 file, the elements should be of type
21287 @code{<nginx-server-configuration>}.
21289 The following example would setup NGinx to serve @code{www.example.com}
21290 from the @code{/srv/http/www.example.com} directory, without using
21293 (service nginx-service-type
21294 (nginx-configuration
21296 (list (nginx-server-configuration
21297 (server-name '("www.example.com"))
21298 (root "/srv/http/www.example.com"))))))
21301 @item @code{upstream-blocks} (default: @code{'()})
21302 A list of @dfn{upstream blocks} to create in the generated configuration
21303 file, the elements should be of type
21304 @code{<nginx-upstream-configuration>}.
21306 Configuring upstreams through the @code{upstream-blocks} can be useful
21307 when combined with @code{locations} in the
21308 @code{<nginx-server-configuration>} records. The following example
21309 creates a server configuration with one location configuration, that
21310 will proxy requests to a upstream configuration, which will handle
21311 requests with two servers.
21316 (nginx-configuration
21318 (list (nginx-server-configuration
21319 (server-name '("www.example.com"))
21320 (root "/srv/http/www.example.com")
21323 (nginx-location-configuration
21325 (body '("proxy_pass http://server-proxy;"))))))))
21327 (list (nginx-upstream-configuration
21328 (name "server-proxy")
21329 (servers (list "server1.example.com"
21330 "server2.example.com")))))))
21333 @item @code{file} (default: @code{#f})
21334 If a configuration @var{file} is provided, this will be used, rather than
21335 generating a configuration file from the provided @code{log-directory},
21336 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
21337 proper operation, these arguments should match what is in @var{file} to ensure
21338 that the directories are created when the service is activated.
21340 This can be useful if you have an existing configuration file, or it's
21341 not possible to do what is required through the other parts of the
21342 nginx-configuration record.
21344 @item @code{server-names-hash-bucket-size} (default: @code{#f})
21345 Bucket size for the server names hash tables, defaults to @code{#f} to
21346 use the size of the processors cache line.
21348 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
21349 Maximum bucket size for the server names hash tables.
21351 @item @code{modules} (default: @code{'()})
21352 List of nginx dynamic modules to load. This should be a list of file
21353 names of loadable modules, as in this example:
21358 (file-append nginx-accept-language-module "\
21359 /etc/nginx/modules/ngx_http_accept_language_module.so")))
21362 @item @code{global-directives} (default: @code{'((events . ()))})
21363 Association list of global directives for the top level of the nginx
21364 configuration. Values may themselves be association lists.
21368 `((worker_processes . 16)
21370 (events . ((worker_connections . 1024)))))
21373 @item @code{extra-content} (default: @code{""})
21374 Extra content for the @code{http} block. Should be string or a string
21375 valued G-expression.
21380 @deftp {Data Type} nginx-server-configuration
21381 Data type representing the configuration of an nginx server block.
21382 This type has the following parameters:
21385 @item @code{listen} (default: @code{'("80" "443 ssl")})
21386 Each @code{listen} directive sets the address and port for IP, or the
21387 path for a UNIX-domain socket on which the server will accept requests.
21388 Both address and port, or only address or only port can be specified.
21389 An address may also be a hostname, for example:
21392 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
21395 @item @code{server-name} (default: @code{(list 'default)})
21396 A list of server names this server represents. @code{'default} represents the
21397 default server for connections matching no other server.
21399 @item @code{root} (default: @code{"/srv/http"})
21400 Root of the website nginx will serve.
21402 @item @code{locations} (default: @code{'()})
21403 A list of @dfn{nginx-location-configuration} or
21404 @dfn{nginx-named-location-configuration} records to use within this
21407 @item @code{index} (default: @code{(list "index.html")})
21408 Index files to look for when clients ask for a directory. If it cannot be found,
21409 Nginx will send the list of files in the directory.
21411 @item @code{try-files} (default: @code{'()})
21412 A list of files whose existence is checked in the specified order.
21413 @code{nginx} will use the first file it finds to process the request.
21415 @item @code{ssl-certificate} (default: @code{#f})
21416 Where to find the certificate for secure connections. Set it to @code{#f} if
21417 you don't have a certificate or you don't want to use HTTPS.
21419 @item @code{ssl-certificate-key} (default: @code{#f})
21420 Where to find the private key for secure connections. Set it to @code{#f} if
21421 you don't have a key or you don't want to use HTTPS.
21423 @item @code{server-tokens?} (default: @code{#f})
21424 Whether the server should add its configuration to response.
21426 @item @code{raw-content} (default: @code{'()})
21427 A list of raw lines added to the server block.
21432 @deftp {Data Type} nginx-upstream-configuration
21433 Data type representing the configuration of an nginx @code{upstream}
21434 block. This type has the following parameters:
21438 Name for this group of servers.
21440 @item @code{servers}
21441 Specify the addresses of the servers in the group. The address can be
21442 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
21443 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
21444 prefix @samp{unix:}. For addresses using an IP address or domain name,
21445 the default port is 80, and a different port can be specified
21451 @deftp {Data Type} nginx-location-configuration
21452 Data type representing the configuration of an nginx @code{location}
21453 block. This type has the following parameters:
21457 URI which this location block matches.
21459 @anchor{nginx-location-configuration body}
21461 Body of the location block, specified as a list of strings. This can contain
21463 configuration directives. For example, to pass requests to a upstream
21464 server group defined using an @code{nginx-upstream-configuration} block,
21465 the following directive would be specified in the body @samp{(list "proxy_pass
21466 http://upstream-name;")}.
21471 @deftp {Data Type} nginx-named-location-configuration
21472 Data type representing the configuration of an nginx named location
21473 block. Named location blocks are used for request redirection, and not
21474 used for regular request processing. This type has the following
21479 Name to identify this location block.
21482 @xref{nginx-location-configuration body}, as the body for named location
21483 blocks can be used in a similar way to the
21484 @code{nginx-location-configuration body}. One restriction is that the
21485 body of a named location block cannot contain location blocks.
21490 @subsubheading Varnish Cache
21492 Varnish is a fast cache server that sits in between web applications
21493 and end users. It proxies requests from clients and caches the
21494 accessed URLs such that multiple requests for the same resource only
21495 creates one request to the back-end.
21497 @defvr {Scheme Variable} varnish-service-type
21498 Service type for the Varnish daemon.
21501 @deftp {Data Type} varnish-configuration
21502 Data type representing the @code{varnish} service configuration.
21503 This type has the following parameters:
21506 @item @code{package} (default: @code{varnish})
21507 The Varnish package to use.
21509 @item @code{name} (default: @code{"default"})
21510 A name for this Varnish instance. Varnish will create a directory in
21511 @file{/var/varnish/} with this name and keep temporary files there. If
21512 the name starts with a forward slash, it is interpreted as an absolute
21515 Pass the @code{-n} argument to other Varnish programs to connect to the
21516 named instance, e.g.@: @command{varnishncsa -n default}.
21518 @item @code{backend} (default: @code{"localhost:8080"})
21519 The backend to use. This option has no effect if @code{vcl} is set.
21521 @item @code{vcl} (default: #f)
21522 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
21523 is @code{#f}, Varnish will proxy @code{backend} using the default
21524 configuration. Otherwise this must be a file-like object with valid
21527 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
21528 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
21529 can do something along these lines:
21532 (define %gnu-mirror
21533 (plain-file "gnu.vcl"
21535 backend gnu @{ .host = \"www.gnu.org\"; @}"))
21539 (services (cons (service varnish-service-type
21540 (varnish-configuration
21542 (vcl %gnu-mirror)))
21546 The configuration of an already running Varnish instance can be inspected
21547 and changed using the @command{varnishadm} program.
21549 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
21550 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
21551 comprehensive documentation on Varnish and its configuration language.
21553 @item @code{listen} (default: @code{'("localhost:80")})
21554 List of addresses Varnish will listen on.
21556 @item @code{storage} (default: @code{'("malloc,128m")})
21557 List of storage backends that will be available in VCL.
21559 @item @code{parameters} (default: @code{'()})
21560 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
21562 @item @code{extra-options} (default: @code{'()})
21563 Additional arguments to pass to the @command{varnishd} process.
21568 @subsubheading Patchwork
21570 Patchwork is a patch tracking system. It can collect patches sent to a
21571 mailing list, and display them in a web interface.
21573 @defvr {Scheme Variable} patchwork-service-type
21574 Service type for Patchwork.
21577 The following example is an example of a minimal service for Patchwork, for
21578 the @code{patchwork.example.com} domain.
21581 (service patchwork-service-type
21582 (patchwork-configuration
21583 (domain "patchwork.example.com")
21585 (patchwork-settings-module
21586 (allowed-hosts (list domain))
21587 (default-from-email "patchwork@@patchwork.example.com")))
21588 (getmail-retriever-config
21589 (getmail-retriever-configuration
21590 (type "SimpleIMAPSSLRetriever")
21591 (server "imap.example.com")
21593 (username "patchwork")
21595 (list (file-append coreutils "/bin/cat")
21596 "/etc/getmail-patchwork-imap-password"))
21598 '((mailboxes . ("Patches"))))))))
21602 There are three records for configuring the Patchwork service. The
21603 @code{<patchwork-configuration>} relates to the configuration for Patchwork
21604 within the HTTPD service.
21606 The @code{settings-module} field within the @code{<patchwork-configuration>}
21607 record can be populated with the @code{<patchwork-settings-module>} record,
21608 which describes a settings module that is generated within the Guix store.
21610 For the @code{database-configuration} field within the
21611 @code{<patchwork-settings-module>}, the
21612 @code{<patchwork-database-configuration>} must be used.
21614 @deftp {Data Type} patchwork-configuration
21615 Data type representing the Patchwork service configuration. This type has the
21616 following parameters:
21619 @item @code{patchwork} (default: @code{patchwork})
21620 The Patchwork package to use.
21622 @item @code{domain}
21623 The domain to use for Patchwork, this is used in the HTTPD service virtual
21626 @item @code{settings-module}
21627 The settings module to use for Patchwork. As a Django application, Patchwork
21628 is configured with a Python module containing the settings. This can either be
21629 an instance of the @code{<patchwork-settings-module>} record, any other record
21630 that represents the settings in the store, or a directory outside of the
21633 @item @code{static-path} (default: @code{"/static/"})
21634 The path under which the HTTPD service should serve the static files.
21636 @item @code{getmail-retriever-config}
21637 The getmail-retriever-configuration record value to use with
21638 Patchwork. Getmail will be configured with this value, the messages will be
21639 delivered to Patchwork.
21644 @deftp {Data Type} patchwork-settings-module
21645 Data type representing a settings module for Patchwork. Some of these
21646 settings relate directly to Patchwork, but others relate to Django, the web
21647 framework used by Patchwork, or the Django Rest Framework library. This type
21648 has the following parameters:
21651 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
21652 The database connection settings used for Patchwork. See the
21653 @code{<patchwork-database-configuration>} record type for more information.
21655 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
21656 Patchwork, as a Django web application uses a secret key for cryptographically
21657 signing values. This file should contain a unique unpredictable value.
21659 If this file does not exist, it will be created and populated with a random
21660 value by the patchwork-setup shepherd service.
21662 This setting relates to Django.
21664 @item @code{allowed-hosts}
21665 A list of valid hosts for this Patchwork service. This should at least include
21666 the domain specified in the @code{<patchwork-configuration>} record.
21668 This is a Django setting.
21670 @item @code{default-from-email}
21671 The email address from which Patchwork should send email by default.
21673 This is a Patchwork setting.
21675 @item @code{static-url} (default: @code{#f})
21676 The URL to use when serving static assets. It can be part of a URL, or a full
21677 URL, but must end in a @code{/}.
21679 If the default value is used, the @code{static-path} value from the
21680 @code{<patchwork-configuration>} record will be used.
21682 This is a Django setting.
21684 @item @code{admins} (default: @code{'()})
21685 Email addresses to send the details of errors that occur. Each value should
21686 be a list containing two elements, the name and then the email address.
21688 This is a Django setting.
21690 @item @code{debug?} (default: @code{#f})
21691 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
21692 messages will be shown.
21694 This is a Django setting.
21696 @item @code{enable-rest-api?} (default: @code{#t})
21697 Whether to enable the Patchwork REST API.
21699 This is a Patchwork setting.
21701 @item @code{enable-xmlrpc?} (default: @code{#t})
21702 Whether to enable the XML RPC API.
21704 This is a Patchwork setting.
21706 @item @code{force-https-links?} (default: @code{#t})
21707 Whether to use HTTPS links on Patchwork pages.
21709 This is a Patchwork setting.
21711 @item @code{extra-settings} (default: @code{""})
21712 Extra code to place at the end of the Patchwork settings module.
21717 @deftp {Data Type} patchwork-database-configuration
21718 Data type representing the database configuration for Patchwork.
21721 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
21722 The database engine to use.
21724 @item @code{name} (default: @code{"patchwork"})
21725 The name of the database to use.
21727 @item @code{user} (default: @code{"httpd"})
21728 The user to connect to the database as.
21730 @item @code{password} (default: @code{""})
21731 The password to use when connecting to the database.
21733 @item @code{host} (default: @code{""})
21734 The host to make the database connection to.
21736 @item @code{port} (default: @code{""})
21737 The port on which to connect to the database.
21742 @subsubheading Mumi
21744 @cindex Mumi, Debbugs Web interface
21745 @cindex Debbugs, Mumi Web interface
21746 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
21747 Web interface to the Debbugs bug tracker, by default for
21748 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
21749 but it also fetches and indexes mail retrieved from Debbugs.
21751 @defvr {Scheme Variable} mumi-service-type
21752 This is the service type for Mumi.
21755 @deftp {Data Type} mumi-configuration
21756 Data type representing the Mumi service configuration. This type has the
21760 @item @code{mumi} (default: @code{mumi})
21761 The Mumi package to use.
21763 @item @code{mailer?} (default: @code{#true})
21764 Whether to enable or disable the mailer component.
21766 @item @code{mumi-configuration-sender}
21767 The email address used as the sender for comments.
21769 @item @code{mumi-configuration-smtp}
21770 A URI to configure the SMTP settings for Mailutils. This could be
21771 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
21772 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
21773 mailutils, GNU@tie{}Mailutils}.
21779 @subsubheading FastCGI
21782 FastCGI is an interface between the front-end and the back-end of a web
21783 service. It is a somewhat legacy facility; new web services should
21784 generally just talk HTTP between the front-end and the back-end.
21785 However there are a number of back-end services such as PHP or the
21786 optimized HTTP Git repository access that use FastCGI, so we have
21787 support for it in Guix.
21789 To use FastCGI, you configure the front-end web server (e.g., nginx) to
21790 dispatch some subset of its requests to the fastcgi backend, which
21791 listens on a local TCP or UNIX socket. There is an intermediary
21792 @code{fcgiwrap} program that sits between the actual backend process and
21793 the web server. The front-end indicates which backend program to run,
21794 passing that information to the @code{fcgiwrap} process.
21796 @defvr {Scheme Variable} fcgiwrap-service-type
21797 A service type for the @code{fcgiwrap} FastCGI proxy.
21800 @deftp {Data Type} fcgiwrap-configuration
21801 Data type representing the configuration of the @code{fcgiwrap} service.
21802 This type has the following parameters:
21804 @item @code{package} (default: @code{fcgiwrap})
21805 The fcgiwrap package to use.
21807 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
21808 The socket on which the @code{fcgiwrap} process should listen, as a
21809 string. Valid @var{socket} values include
21810 @code{unix:@var{/path/to/unix/socket}},
21811 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
21812 @code{tcp6:[@var{ipv6_addr}]:port}.
21814 @item @code{user} (default: @code{fcgiwrap})
21815 @itemx @code{group} (default: @code{fcgiwrap})
21816 The user and group names, as strings, under which to run the
21817 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
21818 the user asks for the specific user or group names @code{fcgiwrap} that
21819 the corresponding user and/or group is present on the system.
21821 It is possible to configure a FastCGI-backed web service to pass HTTP
21822 authentication information from the front-end to the back-end, and to
21823 allow @code{fcgiwrap} to run the back-end process as a corresponding
21824 local user. To enable this capability on the back-end, run
21825 @code{fcgiwrap} as the @code{root} user and group. Note that this
21826 capability also has to be configured on the front-end as well.
21831 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
21832 with some additional features useful for sites of any size.
21834 These features include:
21836 @item Adaptive process spawning
21837 @item Basic statistics (similar to Apache's mod_status)
21838 @item Advanced process management with graceful stop/start
21839 @item Ability to start workers with different uid/gid/chroot/environment
21840 and different php.ini (replaces safe_mode)
21841 @item Stdout & stderr logging
21842 @item Emergency restart in case of accidental opcode cache destruction
21843 @item Accelerated upload support
21844 @item Support for a "slowlog"
21845 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
21846 a special function to finish request & flush all data while continuing to do
21847 something time-consuming (video converting, stats processing, etc.)
21849 ...@: and much more.
21851 @defvr {Scheme Variable} php-fpm-service-type
21852 A Service type for @code{php-fpm}.
21855 @deftp {Data Type} php-fpm-configuration
21856 Data Type for php-fpm service configuration.
21858 @item @code{php} (default: @code{php})
21859 The php package to use.
21860 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
21861 The address on which to accept FastCGI requests. Valid syntaxes are:
21863 @item @code{"ip.add.re.ss:port"}
21864 Listen on a TCP socket to a specific address on a specific port.
21865 @item @code{"port"}
21866 Listen on a TCP socket to all addresses on a specific port.
21867 @item @code{"/path/to/unix/socket"}
21868 Listen on a unix socket.
21871 @item @code{user} (default: @code{php-fpm})
21872 User who will own the php worker processes.
21873 @item @code{group} (default: @code{php-fpm})
21874 Group of the worker processes.
21875 @item @code{socket-user} (default: @code{php-fpm})
21876 User who can speak to the php-fpm socket.
21877 @item @code{socket-group} (default: @code{nginx})
21878 Group that can speak to the php-fpm socket.
21879 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
21880 The process id of the php-fpm process is written to this file
21881 once the service has started.
21882 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
21883 Log for the php-fpm master process.
21884 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
21885 Detailed settings for the php-fpm process manager.
21888 @item @code{<php-fpm-dynamic-process-manager-configuration>}
21889 @item @code{<php-fpm-static-process-manager-configuration>}
21890 @item @code{<php-fpm-on-demand-process-manager-configuration>}
21892 @item @code{display-errors} (default @code{#f})
21893 Determines whether php errors and warning should be sent to clients
21894 and displayed in their browsers.
21895 This is useful for local php development, but a security risk for public sites,
21896 as error messages can reveal passwords and personal data.
21897 @item @code{timezone} (default @code{#f})
21898 Specifies @code{php_admin_value[date.timezone]} parameter.
21899 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
21900 This file will log the @code{stderr} outputs of php worker processes.
21901 Can be set to @code{#f} to disable logging.
21902 @item @code{file} (default @code{#f})
21903 An optional override of the whole configuration.
21904 You can use the @code{mixed-text-file} function or an absolute filepath for it.
21908 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
21909 Data Type for the @code{dynamic} php-fpm process manager. With the
21910 @code{dynamic} process manager, spare worker processes are kept around
21911 based on it's configured limits.
21913 @item @code{max-children} (default: @code{5})
21914 Maximum of worker processes.
21915 @item @code{start-servers} (default: @code{2})
21916 How many worker processes should be started on start-up.
21917 @item @code{min-spare-servers} (default: @code{1})
21918 How many spare worker processes should be kept around at minimum.
21919 @item @code{max-spare-servers} (default: @code{3})
21920 How many spare worker processes should be kept around at maximum.
21924 @deftp {Data type} php-fpm-static-process-manager-configuration
21925 Data Type for the @code{static} php-fpm process manager. With the
21926 @code{static} process manager, an unchanging number of worker processes
21929 @item @code{max-children} (default: @code{5})
21930 Maximum of worker processes.
21934 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
21935 Data Type for the @code{on-demand} php-fpm process manager. With the
21936 @code{on-demand} process manager, worker processes are only created as
21939 @item @code{max-children} (default: @code{5})
21940 Maximum of worker processes.
21941 @item @code{process-idle-timeout} (default: @code{10})
21942 The time in seconds after which a process with no requests is killed.
21947 @deffn {Scheme Procedure} nginx-php-location @
21948 [#:nginx-package nginx] @
21949 [socket (string-append "/var/run/php" @
21950 (version-major (package-version php)) @
21952 A helper function to quickly add php to an @code{nginx-server-configuration}.
21955 A simple services setup for nginx with php can look like this:
21957 (services (cons* (service dhcp-client-service-type)
21958 (service php-fpm-service-type)
21959 (service nginx-service-type
21960 (nginx-server-configuration
21961 (server-name '("example.com"))
21962 (root "/srv/http/")
21964 (list (nginx-php-location)))
21966 (ssl-certificate #f)
21967 (ssl-certificate-key #f)))
21971 @cindex cat-avatar-generator
21972 The cat avatar generator is a simple service to demonstrate the use of php-fpm
21973 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
21974 the hash of a user's email address.
21976 @deffn {Scheme Procedure} cat-avatar-generator-service @
21977 [#:cache-dir "/var/cache/cat-avatar-generator"] @
21978 [#:package cat-avatar-generator] @
21979 [#:configuration (nginx-server-configuration)]
21980 Returns an nginx-server-configuration that inherits @code{configuration}. It
21981 extends the nginx configuration to add a server block that serves @code{package},
21982 a version of cat-avatar-generator. During execution, cat-avatar-generator will
21983 be able to use @code{cache-dir} as its cache directory.
21986 A simple setup for cat-avatar-generator can look like this:
21988 (services (cons* (cat-avatar-generator-service
21990 (nginx-server-configuration
21991 (server-name '("example.com"))))
21996 @subsubheading Hpcguix-web
21998 @cindex hpcguix-web
21999 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
22000 program is a customizable web interface to browse Guix packages,
22001 initially designed for users of high-performance computing (HPC)
22004 @defvr {Scheme Variable} hpcguix-web-service-type
22005 The service type for @code{hpcguix-web}.
22008 @deftp {Data Type} hpcguix-web-configuration
22009 Data type for the hpcguix-web service configuration.
22013 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
22014 configuration. The main items available in this spec are:
22017 @item @code{title-prefix} (default: @code{"hpcguix | "})
22018 The page title prefix.
22020 @item @code{guix-command} (default: @code{"guix"})
22021 The @command{guix} command.
22023 @item @code{package-filter-proc} (default: @code{(const #t)})
22024 A procedure specifying how to filter packages that are displayed.
22026 @item @code{package-page-extension-proc} (default: @code{(const '())})
22027 Extension package for @code{hpcguix-web}.
22029 @item @code{menu} (default: @code{'()})
22030 Additional entry in page @code{menu}.
22032 @item @code{channels} (default: @code{%default-channels})
22033 List of channels from which the package list is built (@pxref{Channels}).
22035 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
22036 The expiration time, in seconds, after which the package list is rebuilt from
22037 the latest instances of the given channels.
22040 See the hpcguix-web repository for a
22041 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
22044 @item @code{package} (default: @code{hpcguix-web})
22045 The hpcguix-web package to use.
22049 A typical hpcguix-web service declaration looks like this:
22052 (service hpcguix-web-service-type
22053 (hpcguix-web-configuration
22055 #~(define site-config
22056 (hpcweb-configuration
22057 (title-prefix "Guix-HPC - ")
22058 (menu '(("/about" "ABOUT"))))))))
22062 The hpcguix-web service periodically updates the package list it publishes by
22063 pulling channels from Git. To that end, it needs to access X.509 certificates
22064 so that it can authenticate Git servers when communicating over HTTPS, and it
22065 assumes that @file{/etc/ssl/certs} contains those certificates.
22067 Thus, make sure to add @code{nss-certs} or another certificate package to the
22068 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
22069 more information on X.509 certificates.
22072 @node Certificate Services
22073 @subsection Certificate Services
22076 @cindex HTTP, HTTPS
22077 @cindex Let's Encrypt
22078 @cindex TLS certificates
22079 The @code{(gnu services certbot)} module provides a service to
22080 automatically obtain a valid TLS certificate from the Let's Encrypt
22081 certificate authority. These certificates can then be used to serve
22082 content securely over HTTPS or other TLS-based protocols, with the
22083 knowledge that the client will be able to verify the server's
22086 @url{https://letsencrypt.org/, Let's Encrypt} provides the
22087 @code{certbot} tool to automate the certification process. This tool
22088 first securely generates a key on the server. It then makes a request
22089 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
22090 checks that the request originates from the host in question by using a
22091 challenge-response protocol, requiring the server to provide its
22092 response over HTTP. If that protocol completes successfully, the CA
22093 signs the key, resulting in a certificate. That certificate is valid
22094 for a limited period of time, and therefore to continue to provide TLS
22095 services, the server needs to periodically ask the CA to renew its
22098 The certbot service automates this process: the initial key
22099 generation, the initial certification request to the Let's Encrypt
22100 service, the web server challenge/response integration, writing the
22101 certificate to disk, the automated periodic renewals, and the deployment
22102 tasks associated with the renewal (e.g.@: reloading services, copying keys
22103 with different permissions).
22105 Certbot is run twice a day, at a random minute within the hour. It
22106 won't do anything until your certificates are due for renewal or
22107 revoked, but running it regularly would give your service a chance of
22108 staying online in case a Let's Encrypt-initiated revocation happened for
22111 By using this service, you agree to the ACME Subscriber Agreement, which
22112 can be found there:
22113 @url{https://acme-v01.api.letsencrypt.org/directory}.
22115 @defvr {Scheme Variable} certbot-service-type
22116 A service type for the @code{certbot} Let's Encrypt client. Its value
22117 must be a @code{certbot-configuration} record as in this example:
22120 (define %nginx-deploy-hook
22122 "nginx-deploy-hook"
22123 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
22124 (kill pid SIGHUP))))
22126 (service certbot-service-type
22127 (certbot-configuration
22128 (email "foo@@example.net")
22131 (certificate-configuration
22132 (domains '("example.net" "www.example.net"))
22133 (deploy-hook %nginx-deploy-hook))
22134 (certificate-configuration
22135 (domains '("bar.example.net")))))))
22138 See below for details about @code{certbot-configuration}.
22141 @deftp {Data Type} certbot-configuration
22142 Data type representing the configuration of the @code{certbot} service.
22143 This type has the following parameters:
22146 @item @code{package} (default: @code{certbot})
22147 The certbot package to use.
22149 @item @code{webroot} (default: @code{/var/www})
22150 The directory from which to serve the Let's Encrypt challenge/response
22153 @item @code{certificates} (default: @code{()})
22154 A list of @code{certificates-configuration}s for which to generate
22155 certificates and request signatures. Each certificate has a @code{name}
22156 and several @code{domains}.
22159 Mandatory email used for registration, recovery contact, and important
22160 account notifications.
22162 @item @code{server} (default: @code{#f})
22163 Optional URL of ACME server. Setting this overrides certbot's default,
22164 which is the Let's Encrypt server.
22166 @item @code{rsa-key-size} (default: @code{2048})
22167 Size of the RSA key.
22169 @item @code{default-location} (default: @i{see below})
22170 The default @code{nginx-location-configuration}. Because @code{certbot}
22171 needs to be able to serve challenges and responses, it needs to be able
22172 to run a web server. It does so by extending the @code{nginx} web
22173 service with an @code{nginx-server-configuration} listening on the
22174 @var{domains} on port 80, and which has a
22175 @code{nginx-location-configuration} for the @code{/.well-known/} URI
22176 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
22177 these nginx configuration data types.
22179 Requests to other URL paths will be matched by the
22180 @code{default-location}, which if present is added to all
22181 @code{nginx-server-configuration}s.
22183 By default, the @code{default-location} will issue a redirect from
22184 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
22185 you to define what to serve on your site via @code{https}.
22187 Pass @code{#f} to not issue a default location.
22191 @deftp {Data Type} certificate-configuration
22192 Data type representing the configuration of a certificate.
22193 This type has the following parameters:
22196 @item @code{name} (default: @i{see below})
22197 This name is used by Certbot for housekeeping and in file paths; it
22198 doesn't affect the content of the certificate itself. To see
22199 certificate names, run @code{certbot certificates}.
22201 Its default is the first provided domain.
22203 @item @code{domains} (default: @code{()})
22204 The first domain provided will be the subject CN of the certificate, and
22205 all domains will be Subject Alternative Names on the certificate.
22207 @item @code{challenge} (default: @code{#f})
22208 The challenge type that has to be run by certbot. If @code{#f} is specified,
22209 default to the HTTP challenge. If a value is specified, defaults to the
22210 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
22211 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
22212 and gives Let's Encrypt permission to log the public IP address of the
22213 requesting machine.
22215 @item @code{authentication-hook} (default: @code{#f})
22216 Command to be run in a shell once for each certificate challenge to be
22217 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
22218 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
22219 contains the validation string and @code{$CERTBOT_TOKEN} contains the
22220 file name of the resource requested when performing an HTTP-01 challenge.
22222 @item @code{cleanup-hook} (default: @code{#f})
22223 Command to be run in a shell once for each certificate challenge that
22224 have been answered by the @code{auth-hook}. For this command, the shell
22225 variables available in the @code{auth-hook} script are still available, and
22226 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
22227 of the @code{auth-hook} script.
22229 @item @code{deploy-hook} (default: @code{#f})
22230 Command to be run in a shell once for each successfully issued
22231 certificate. For this command, the shell variable
22232 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
22233 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
22234 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
22235 contain a space-delimited list of renewed certificate domains (for
22236 example, @samp{"example.com www.example.com"}.
22241 For each @code{certificate-configuration}, the certificate is saved to
22242 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
22243 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
22245 @subsection DNS Services
22246 @cindex DNS (domain name system)
22247 @cindex domain name system (DNS)
22249 The @code{(gnu services dns)} module provides services related to the
22250 @dfn{domain name system} (DNS). It provides a server service for hosting
22251 an @emph{authoritative} DNS server for multiple zones, slave or master.
22252 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
22253 caching and forwarding DNS server for the LAN, which uses
22254 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
22256 @subsubheading Knot Service
22258 An example configuration of an authoritative server for two zones, one master
22262 (define-zone-entries example.org.zone
22263 ;; Name TTL Class Type Data
22264 ("@@" "" "IN" "A" "127.0.0.1")
22265 ("@@" "" "IN" "NS" "ns")
22266 ("ns" "" "IN" "A" "127.0.0.1"))
22268 (define master-zone
22269 (knot-zone-configuration
22270 (domain "example.org")
22272 (origin "example.org")
22273 (entries example.org.zone)))))
22276 (knot-zone-configuration
22277 (domain "plop.org")
22278 (dnssec-policy "default")
22279 (master (list "plop-master"))))
22281 (define plop-master
22282 (knot-remote-configuration
22284 (address (list "208.76.58.171"))))
22288 (services (cons* (service knot-service-type
22289 (knot-configuration
22290 (remotes (list plop-master))
22291 (zones (list master-zone slave-zone))))
22296 @deffn {Scheme Variable} knot-service-type
22297 This is the type for the Knot DNS server.
22299 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
22300 zones, that is to say domain names you would buy from a registrar. This server
22301 is not a resolver, meaning that it can only resolve names for which it is
22302 authoritative. This server can be configured to serve zones as a master server
22303 or a slave server as a per-zone basis. Slave zones will get their data from
22304 masters, and will serve it as an authoritative server. From the point of view
22305 of a resolver, there is no difference between master and slave.
22307 The following data types are used to configure the Knot DNS server:
22310 @deftp {Data Type} knot-key-configuration
22311 Data type representing a key.
22312 This type has the following parameters:
22315 @item @code{id} (default: @code{""})
22316 An identifier for other configuration fields to refer to this key. IDs must
22317 be unique and must not be empty.
22319 @item @code{algorithm} (default: @code{#f})
22320 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
22321 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
22322 and @code{'hmac-sha512}.
22324 @item @code{secret} (default: @code{""})
22325 The secret key itself.
22330 @deftp {Data Type} knot-acl-configuration
22331 Data type representing an Access Control List (ACL) configuration.
22332 This type has the following parameters:
22335 @item @code{id} (default: @code{""})
22336 An identifier for ether configuration fields to refer to this key. IDs must be
22337 unique and must not be empty.
22339 @item @code{address} (default: @code{'()})
22340 An ordered list of IP addresses, network subnets, or network ranges represented
22341 with strings. The query must match one of them. Empty value means that
22342 address match is not required.
22344 @item @code{key} (default: @code{'()})
22345 An ordered list of references to keys represented with strings. The string
22346 must match a key ID defined in a @code{knot-key-configuration}. No key means
22347 that a key is not require to match that ACL.
22349 @item @code{action} (default: @code{'()})
22350 An ordered list of actions that are permitted or forbidden by this ACL. Possible
22351 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
22352 and @code{'update}.
22354 @item @code{deny?} (default: @code{#f})
22355 When true, the ACL defines restrictions. Listed actions are forbidden. When
22356 false, listed actions are allowed.
22361 @deftp {Data Type} zone-entry
22362 Data type representing a record entry in a zone file.
22363 This type has the following parameters:
22366 @item @code{name} (default: @code{"@@"})
22367 The name of the record. @code{"@@"} refers to the origin of the zone. Names
22368 are relative to the origin of the zone. For example, in the @code{example.org}
22369 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
22370 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
22371 refers to @code{ns.example.org}.
22373 @item @code{ttl} (default: @code{""})
22374 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
22376 @item @code{class} (default: @code{"IN"})
22377 The class of the record. Knot currently supports only @code{"IN"} and
22378 partially @code{"CH"}.
22380 @item @code{type} (default: @code{"A"})
22381 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
22382 address), NS (Name Server) and MX (Mail eXchange). Many other types are
22385 @item @code{data} (default: @code{""})
22386 The data contained in the record. For instance an IP address associated with
22387 an A record, or a domain name associated with an NS record. Remember that
22388 domain names are relative to the origin unless they end with a dot.
22393 @deftp {Data Type} zone-file
22394 Data type representing the content of a zone file.
22395 This type has the following parameters:
22398 @item @code{entries} (default: @code{'()})
22399 The list of entries. The SOA record is taken care of, so you don't need to
22400 put it in the list of entries. This list should probably contain an entry
22401 for your primary authoritative DNS server. Other than using a list of entries
22402 directly, you can use @code{define-zone-entries} to define a object containing
22403 the list of entries more easily, that you can later pass to the @code{entries}
22404 field of the @code{zone-file}.
22406 @item @code{origin} (default: @code{""})
22407 The name of your zone. This parameter cannot be empty.
22409 @item @code{ns} (default: @code{"ns"})
22410 The domain of your primary authoritative DNS server. The name is relative to
22411 the origin, unless it ends with a dot. It is mandatory that this primary
22412 DNS server corresponds to an NS record in the zone and that it is associated
22413 to an IP address in the list of entries.
22415 @item @code{mail} (default: @code{"hostmaster"})
22416 An email address people can contact you at, as the owner of the zone. This
22417 is translated as @code{<mail>@@<origin>}.
22419 @item @code{serial} (default: @code{1})
22420 The serial number of the zone. As this is used to keep track of changes by
22421 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
22422 Always increment it when you make a change in your zone.
22424 @item @code{refresh} (default: @code{(* 2 24 3600)})
22425 The frequency at which slaves will do a zone transfer. This value is a number
22426 of seconds. It can be computed by multiplications or with
22427 @code{(string->duration)}.
22429 @item @code{retry} (default: @code{(* 15 60)})
22430 The period after which a slave will retry to contact its master when it fails
22431 to do so a first time.
22433 @item @code{expiry} (default: @code{(* 14 24 3600)})
22434 Default TTL of records. Existing records are considered correct for at most
22435 this amount of time. After this period, resolvers will invalidate their cache
22436 and check again that it still exists.
22438 @item @code{nx} (default: @code{3600})
22439 Default TTL of inexistant records. This delay is usually short because you want
22440 your new domains to reach everyone quickly.
22445 @deftp {Data Type} knot-remote-configuration
22446 Data type representing a remote configuration.
22447 This type has the following parameters:
22450 @item @code{id} (default: @code{""})
22451 An identifier for other configuration fields to refer to this remote. IDs must
22452 be unique and must not be empty.
22454 @item @code{address} (default: @code{'()})
22455 An ordered list of destination IP addresses. Addresses are tried in sequence.
22456 An optional port can be given with the @@ separator. For instance:
22457 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
22459 @item @code{via} (default: @code{'()})
22460 An ordered list of source IP addresses. An empty list will have Knot choose
22461 an appropriate source IP. An optional port can be given with the @@ separator.
22462 The default is to choose at random.
22464 @item @code{key} (default: @code{#f})
22465 A reference to a key, that is a string containing the identifier of a key
22466 defined in a @code{knot-key-configuration} field.
22471 @deftp {Data Type} knot-keystore-configuration
22472 Data type representing a keystore to hold dnssec keys.
22473 This type has the following parameters:
22476 @item @code{id} (default: @code{""})
22477 The id of the keystore. It must not be empty.
22479 @item @code{backend} (default: @code{'pem})
22480 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
22482 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
22483 The configuration string of the backend. An example for the PKCS#11 is:
22484 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
22485 For the pem backend, the string represents a path in the file system.
22490 @deftp {Data Type} knot-policy-configuration
22491 Data type representing a dnssec policy. Knot DNS is able to automatically
22492 sign your zones. It can either generate and manage your keys automatically or
22493 use keys that you generate.
22495 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
22496 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
22497 zone. In order to be trusted, the KSK needs to be present in the parent zone
22498 (usually a top-level domain). If your registrar supports dnssec, you will
22499 have to send them your KSK's hash so they can add a DS record in their zone.
22500 This is not automated and need to be done each time you change your KSK.
22502 The policy also defines the lifetime of keys. Usually, ZSK can be changed
22503 easily and use weaker cryptographic functions (they use lower parameters) in
22504 order to sign records quickly, so they are changed often. The KSK however
22505 requires manual interaction with the registrar, so they are changed less often
22506 and use stronger parameters because they sign only one record.
22508 This type has the following parameters:
22511 @item @code{id} (default: @code{""})
22512 The id of the policy. It must not be empty.
22514 @item @code{keystore} (default: @code{"default"})
22515 A reference to a keystore, that is a string containing the identifier of a
22516 keystore defined in a @code{knot-keystore-configuration} field. The
22517 @code{"default"} identifier means the default keystore (a kasp database that
22518 was setup by this service).
22520 @item @code{manual?} (default: @code{#f})
22521 Whether the key management is manual or automatic.
22523 @item @code{single-type-signing?} (default: @code{#f})
22524 When @code{#t}, use the Single-Type Signing Scheme.
22526 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
22527 An algorithm of signing keys and issued signatures.
22529 @item @code{ksk-size} (default: @code{256})
22530 The length of the KSK. Note that this value is correct for the default
22531 algorithm, but would be unsecure for other algorithms.
22533 @item @code{zsk-size} (default: @code{256})
22534 The length of the ZSK. Note that this value is correct for the default
22535 algorithm, but would be unsecure for other algorithms.
22537 @item @code{dnskey-ttl} (default: @code{'default})
22538 The TTL value for DNSKEY records added into zone apex. The special
22539 @code{'default} value means same as the zone SOA TTL.
22541 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
22542 The period between ZSK publication and the next rollover initiation.
22544 @item @code{propagation-delay} (default: @code{(* 24 3600)})
22545 An extra delay added for each key rollover step. This value should be high
22546 enough to cover propagation of data from the master server to all slaves.
22548 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
22549 A validity period of newly issued signatures.
22551 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
22552 A period how long before a signature expiration the signature will be refreshed.
22554 @item @code{nsec3?} (default: @code{#f})
22555 When @code{#t}, NSEC3 will be used instead of NSEC.
22557 @item @code{nsec3-iterations} (default: @code{5})
22558 The number of additional times the hashing is performed.
22560 @item @code{nsec3-salt-length} (default: @code{8})
22561 The length of a salt field in octets, which is appended to the original owner
22562 name before hashing.
22564 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
22565 The validity period of newly issued salt field.
22570 @deftp {Data Type} knot-zone-configuration
22571 Data type representing a zone served by Knot.
22572 This type has the following parameters:
22575 @item @code{domain} (default: @code{""})
22576 The domain served by this configuration. It must not be empty.
22578 @item @code{file} (default: @code{""})
22579 The file where this zone is saved. This parameter is ignored by master zones.
22580 Empty means default location that depends on the domain name.
22582 @item @code{zone} (default: @code{(zone-file)})
22583 The content of the zone file. This parameter is ignored by slave zones. It
22584 must contain a zone-file record.
22586 @item @code{master} (default: @code{'()})
22587 A list of master remotes. When empty, this zone is a master. When set, this
22588 zone is a slave. This is a list of remotes identifiers.
22590 @item @code{ddns-master} (default: @code{#f})
22591 The main master. When empty, it defaults to the first master in the list of
22594 @item @code{notify} (default: @code{'()})
22595 A list of slave remote identifiers.
22597 @item @code{acl} (default: @code{'()})
22598 A list of acl identifiers.
22600 @item @code{semantic-checks?} (default: @code{#f})
22601 When set, this adds more semantic checks to the zone.
22603 @item @code{disable-any?} (default: @code{#f})
22604 When set, this forbids queries of the ANY type.
22606 @item @code{zonefile-sync} (default: @code{0})
22607 The delay between a modification in memory and on disk. 0 means immediate
22610 @item @code{zonefile-load} (default: @code{#f})
22611 The way the zone file contents are applied during zone load. Possible values
22615 @item @code{#f} for using the default value from Knot,
22616 @item @code{'none} for not using the zone file at all,
22617 @item @code{'difference} for computing the difference between already available
22618 contents and zone contents and applying it to the current zone contents,
22619 @item @code{'difference-no-serial} for the same as @code{'difference}, but
22620 ignoring the SOA serial in the zone file, while the server takes care of it
22622 @item @code{'whole} for loading zone contents from the zone file.
22625 @item @code{journal-content} (default: @code{#f})
22626 The way the journal is used to store zone and its changes. Possible values
22627 are @code{'none} to not use it at all, @code{'changes} to store changes and
22628 @code{'all} to store contents. @code{#f} does not set this option, so the
22629 default value from Knot is used.
22631 @item @code{max-journal-usage} (default: @code{#f})
22632 The maximum size for the journal on disk. @code{#f} does not set this option,
22633 so the default value from Knot is used.
22635 @item @code{max-journal-depth} (default: @code{#f})
22636 The maximum size of the history. @code{#f} does not set this option, so the
22637 default value from Knot is used.
22639 @item @code{max-zone-size} (default: @code{#f})
22640 The maximum size of the zone file. This limit is enforced for incoming
22641 transfer and updates. @code{#f} does not set this option, so the default
22642 value from Knot is used.
22644 @item @code{dnssec-policy} (default: @code{#f})
22645 A reference to a @code{knot-policy-configuration} record, or the special
22646 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
22649 @item @code{serial-policy} (default: @code{'increment})
22650 A policy between @code{'increment} and @code{'unixtime}.
22655 @deftp {Data Type} knot-configuration
22656 Data type representing the Knot configuration.
22657 This type has the following parameters:
22660 @item @code{knot} (default: @code{knot})
22663 @item @code{run-directory} (default: @code{"/var/run/knot"})
22664 The run directory. This directory will be used for pid file and sockets.
22666 @item @code{includes} (default: @code{'()})
22667 A list of strings or file-like objects denoting other files that must be
22668 included at the top of the configuration file.
22670 @cindex secrets, Knot service
22671 This can be used to manage secrets out-of-band. For example, secret
22672 keys may be stored in an out-of-band file not managed by Guix, and
22673 thus not visible in @file{/gnu/store}---e.g., you could store secret
22674 key configuration in @file{/etc/knot/secrets.conf} and add this file
22675 to the @code{includes} list.
22677 One can generate a secret tsig key (for nsupdate and zone transfers with the
22678 keymgr command from the knot package. Note that the package is not automatically
22679 installed by the service. The following example shows how to generate a new
22683 keymgr -t mysecret > /etc/knot/secrets.conf
22684 chmod 600 /etc/knot/secrets.conf
22687 Also note that the generated key will be named @var{mysecret}, so it is the
22688 name that needs to be used in the @var{key} field of the
22689 @code{knot-acl-configuration} record and in other places that need to refer
22692 It can also be used to add configuration not supported by this interface.
22694 @item @code{listen-v4} (default: @code{"0.0.0.0"})
22695 An ip address on which to listen.
22697 @item @code{listen-v6} (default: @code{"::"})
22698 An ip address on which to listen.
22700 @item @code{listen-port} (default: @code{53})
22701 A port on which to listen.
22703 @item @code{keys} (default: @code{'()})
22704 The list of knot-key-configuration used by this configuration.
22706 @item @code{acls} (default: @code{'()})
22707 The list of knot-acl-configuration used by this configuration.
22709 @item @code{remotes} (default: @code{'()})
22710 The list of knot-remote-configuration used by this configuration.
22712 @item @code{zones} (default: @code{'()})
22713 The list of knot-zone-configuration used by this configuration.
22718 @subsubheading Knot Resolver Service
22720 @deffn {Scheme Variable} knot-resolver-service-type
22721 This this the type of the knot resolver service, whose value should be
22722 an @code{knot-resolver-configuration} object as in this example:
22725 (service knot-resolver-service-type
22726 (knot-resolver-configuration
22727 (kresd-config-file (plain-file "kresd.conf" "
22728 net.listen('192.168.0.1', 5353)
22729 user('knot-resolver', 'knot-resolver')
22730 modules = @{ 'hints > iterate', 'stats', 'predict' @}
22731 cache.size = 100 * MB
22735 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
22738 @deftp {Data Type} knot-resolver-configuration
22739 Data type representing the configuration of knot-resolver.
22742 @item @code{package} (default: @var{knot-resolver})
22743 Package object of the knot DNS resolver.
22745 @item @code{kresd-config-file} (default: %kresd.conf)
22746 File-like object of the kresd configuration file to use, by default it
22747 will listen on @code{127.0.0.1} and @code{::1}.
22749 @item @code{garbage-collection-interval} (default: 1000)
22750 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
22756 @subsubheading Dnsmasq Service
22758 @deffn {Scheme Variable} dnsmasq-service-type
22759 This is the type of the dnsmasq service, whose value should be an
22760 @code{dnsmasq-configuration} object as in this example:
22763 (service dnsmasq-service-type
22764 (dnsmasq-configuration
22766 (servers '("192.168.1.1"))))
22770 @deftp {Data Type} dnsmasq-configuration
22771 Data type representing the configuration of dnsmasq.
22774 @item @code{package} (default: @var{dnsmasq})
22775 Package object of the dnsmasq server.
22777 @item @code{no-hosts?} (default: @code{#f})
22778 When true, don't read the hostnames in /etc/hosts.
22780 @item @code{port} (default: @code{53})
22781 The port to listen on. Setting this to zero completely disables DNS
22782 responses, leaving only DHCP and/or TFTP functions.
22784 @item @code{local-service?} (default: @code{#t})
22785 Accept DNS queries only from hosts whose address is on a local subnet,
22786 ie a subnet for which an interface exists on the server.
22788 @item @code{listen-addresses} (default: @code{'()})
22789 Listen on the given IP addresses.
22791 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
22792 The file to read the IP address of the upstream nameservers from.
22794 @item @code{no-resolv?} (default: @code{#f})
22795 When true, don't read @var{resolv-file}.
22797 @item @code{servers} (default: @code{'()})
22798 Specify IP address of upstream servers directly.
22800 @item @code{addresses} (default: @code{'()})
22801 For each entry, specify an IP address to return for any host in the
22802 given domains. Queries in the domains are never forwarded and always
22803 replied to with the specified IP address.
22805 This is useful for redirecting hosts locally, for example:
22808 (service dnsmasq-service-type
22809 (dnsmasq-configuration
22811 '(; Redirect to a local web-server.
22812 "/example.org/127.0.0.1"
22813 ; Redirect subdomain to a specific IP.
22814 "/subdomain.example.org/192.168.1.42"))))
22817 Note that rules in @file{/etc/hosts} take precedence over this.
22819 @item @code{cache-size} (default: @code{150})
22820 Set the size of dnsmasq's cache. Setting the cache size to zero
22823 @item @code{negative-cache?} (default: @code{#t})
22824 When false, disable negative caching.
22829 @subsubheading ddclient Service
22832 The ddclient service described below runs the ddclient daemon, which takes
22833 care of automatically updating DNS entries for service providers such as
22834 @uref{https://dyn.com/dns/, Dyn}.
22836 The following example show instantiates the service with its default
22840 (service ddclient-service-type)
22843 Note that ddclient needs to access credentials that are stored in a
22844 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
22845 @code{secret-file} below). You are expected to create this file manually, in
22846 an ``out-of-band'' fashion (you @emph{could} make this file part of the
22847 service configuration, for instance by using @code{plain-file}, but it will be
22848 world-readable @i{via} @file{/gnu/store}). See the examples in the
22849 @file{share/ddclient} directory of the @code{ddclient} package.
22851 @c %start of fragment
22853 Available @code{ddclient-configuration} fields are:
22855 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
22856 The ddclient package.
22860 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
22861 The period after which ddclient will retry to check IP and domain name.
22863 Defaults to @samp{300}.
22867 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
22868 Use syslog for the output.
22870 Defaults to @samp{#t}.
22874 @deftypevr {@code{ddclient-configuration} parameter} string mail
22877 Defaults to @samp{"root"}.
22881 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
22882 Mail failed update to user.
22884 Defaults to @samp{"root"}.
22888 @deftypevr {@code{ddclient-configuration} parameter} string pid
22889 The ddclient PID file.
22891 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
22895 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
22896 Enable SSL support.
22898 Defaults to @samp{#t}.
22902 @deftypevr {@code{ddclient-configuration} parameter} string user
22903 Specifies the user name or ID that is used when running ddclient
22906 Defaults to @samp{"ddclient"}.
22910 @deftypevr {@code{ddclient-configuration} parameter} string group
22911 Group of the user who will run the ddclient program.
22913 Defaults to @samp{"ddclient"}.
22917 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
22918 Secret file which will be appended to @file{ddclient.conf} file. This
22919 file contains credentials for use by ddclient. You are expected to
22920 create it manually.
22922 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
22926 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
22927 Extra options will be appended to @file{ddclient.conf} file.
22929 Defaults to @samp{()}.
22934 @c %end of fragment
22938 @subsection VPN Services
22939 @cindex VPN (virtual private network)
22940 @cindex virtual private network (VPN)
22942 The @code{(gnu services vpn)} module provides services related to
22943 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
22944 your machine to connect to a VPN, and a @emph{server} service for your machine
22945 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
22947 @deffn {Scheme Procedure} openvpn-client-service @
22948 [#:config (openvpn-client-configuration)]
22950 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
22953 @deffn {Scheme Procedure} openvpn-server-service @
22954 [#:config (openvpn-server-configuration)]
22956 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
22958 Both can be run simultaneously.
22961 @c %automatically generated documentation
22963 Available @code{openvpn-client-configuration} fields are:
22965 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
22966 The OpenVPN package.
22970 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
22971 The OpenVPN pid file.
22973 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
22977 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
22978 The protocol (UDP or TCP) used to open a channel between clients and
22981 Defaults to @samp{udp}.
22985 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
22986 The device type used to represent the VPN connection.
22988 Defaults to @samp{tun}.
22992 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
22993 The certificate authority to check connections against.
22995 Defaults to @samp{"/etc/openvpn/ca.crt"}.
22999 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
23000 The certificate of the machine the daemon is running on. It should be
23001 signed by the authority given in @code{ca}.
23003 Defaults to @samp{"/etc/openvpn/client.crt"}.
23007 @deftypevr {@code{openvpn-client-configuration} parameter} string key
23008 The key of the machine the daemon is running on. It must be the key whose
23009 certificate is @code{cert}.
23011 Defaults to @samp{"/etc/openvpn/client.key"}.
23015 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
23016 Whether to use the lzo compression algorithm.
23018 Defaults to @samp{#t}.
23022 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
23023 Don't re-read key files across SIGUSR1 or --ping-restart.
23025 Defaults to @samp{#t}.
23029 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
23030 Don't close and reopen TUN/TAP device or run up/down scripts across
23031 SIGUSR1 or --ping-restart restarts.
23033 Defaults to @samp{#t}.
23037 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
23038 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
23039 poll/epoll/select prior to the write operation.
23041 Defaults to @samp{#f}.
23044 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
23047 Defaults to @samp{3}.
23051 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
23052 Add an additional layer of HMAC authentication on top of the TLS control
23053 channel to protect against DoS attacks.
23055 Defaults to @samp{#f}.
23059 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
23060 Authenticate with server using username/password. The option is a file
23061 containing username/password on 2 lines. Do not use a file-like object as it
23062 would be added to the store and readable by any user.
23064 Defaults to @samp{'disabled}.
23067 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
23068 Whether to check the server certificate has server usage extension.
23070 Defaults to @samp{#t}.
23074 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
23075 Bind to a specific local port number.
23077 Defaults to @samp{#f}.
23081 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
23082 Retry resolving server address.
23084 Defaults to @samp{#t}.
23088 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
23089 A list of remote servers to connect to.
23091 Defaults to @samp{()}.
23093 Available @code{openvpn-remote-configuration} fields are:
23095 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
23098 Defaults to @samp{"my-server"}.
23102 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
23103 Port number the server listens to.
23105 Defaults to @samp{1194}.
23110 @c %end of automatic openvpn-client documentation
23112 @c %automatically generated documentation
23114 Available @code{openvpn-server-configuration} fields are:
23116 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
23117 The OpenVPN package.
23121 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
23122 The OpenVPN pid file.
23124 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
23128 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
23129 The protocol (UDP or TCP) used to open a channel between clients and
23132 Defaults to @samp{udp}.
23136 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
23137 The device type used to represent the VPN connection.
23139 Defaults to @samp{tun}.
23143 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
23144 The certificate authority to check connections against.
23146 Defaults to @samp{"/etc/openvpn/ca.crt"}.
23150 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
23151 The certificate of the machine the daemon is running on. It should be
23152 signed by the authority given in @code{ca}.
23154 Defaults to @samp{"/etc/openvpn/client.crt"}.
23158 @deftypevr {@code{openvpn-server-configuration} parameter} string key
23159 The key of the machine the daemon is running on. It must be the key whose
23160 certificate is @code{cert}.
23162 Defaults to @samp{"/etc/openvpn/client.key"}.
23166 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
23167 Whether to use the lzo compression algorithm.
23169 Defaults to @samp{#t}.
23173 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
23174 Don't re-read key files across SIGUSR1 or --ping-restart.
23176 Defaults to @samp{#t}.
23180 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
23181 Don't close and reopen TUN/TAP device or run up/down scripts across
23182 SIGUSR1 or --ping-restart restarts.
23184 Defaults to @samp{#t}.
23188 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
23189 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
23190 poll/epoll/select prior to the write operation.
23192 Defaults to @samp{#f}.
23195 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
23198 Defaults to @samp{3}.
23202 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
23203 Add an additional layer of HMAC authentication on top of the TLS control
23204 channel to protect against DoS attacks.
23206 Defaults to @samp{#f}.
23210 @deftypevr {@code{openvpn-server-configuration} parameter} number port
23211 Specifies the port number on which the server listens.
23213 Defaults to @samp{1194}.
23217 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
23218 An ip and mask specifying the subnet inside the virtual network.
23220 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
23224 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
23225 A CIDR notation specifying the IPv6 subnet inside the virtual network.
23227 Defaults to @samp{#f}.
23231 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
23232 The Diffie-Hellman parameters file.
23234 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
23238 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
23239 The file that records client IPs.
23241 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
23245 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
23246 When true, the server will act as a gateway for its clients.
23248 Defaults to @samp{#f}.
23252 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
23253 When true, clients are allowed to talk to each other inside the VPN.
23255 Defaults to @samp{#f}.
23259 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
23260 Causes ping-like messages to be sent back and forth over the link so
23261 that each side knows when the other side has gone down. @code{keepalive}
23262 requires a pair. The first element is the period of the ping sending,
23263 and the second element is the timeout before considering the other side
23268 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
23269 The maximum number of clients.
23271 Defaults to @samp{100}.
23275 @deftypevr {@code{openvpn-server-configuration} parameter} string status
23276 The status file. This file shows a small report on current connection.
23277 It is truncated and rewritten every minute.
23279 Defaults to @samp{"/var/run/openvpn/status"}.
23283 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
23284 The list of configuration for some clients.
23286 Defaults to @samp{()}.
23288 Available @code{openvpn-ccd-configuration} fields are:
23290 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
23293 Defaults to @samp{"client"}.
23297 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
23300 Defaults to @samp{#f}.
23304 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
23307 Defaults to @samp{#f}.
23314 @c %end of automatic openvpn-server documentation
23317 @node Network File System
23318 @subsection Network File System
23321 The @code{(gnu services nfs)} module provides the following services,
23322 which are most commonly used in relation to mounting or exporting
23323 directory trees as @dfn{network file systems} (NFS).
23325 While it is possible to use the individual components that together make
23326 up a Network File System service, we recommended to configure an NFS
23327 server with the @code{nfs-service-type}.
23329 @subsubheading NFS Service
23330 @cindex NFS, server
23332 The NFS service takes care of setting up all NFS component services,
23333 kernel configuration file systems, and installs configuration files in
23334 the locations that NFS expects.
23336 @defvr {Scheme Variable} nfs-service-type
23337 A service type for a complete NFS server.
23340 @deftp {Data Type} nfs-configuration
23341 This data type represents the configuration of the NFS service and all
23344 It has the following parameters:
23346 @item @code{nfs-utils} (default: @code{nfs-utils})
23347 The nfs-utils package to use.
23349 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
23350 If a list of string values is provided, the @command{rpc.nfsd} daemon
23351 will be limited to supporting the given versions of the NFS protocol.
23353 @item @code{exports} (default: @code{'()})
23354 This is a list of directories the NFS server should export. Each entry
23355 is a list consisting of two elements: a directory name and a string
23356 containing all options. This is an example in which the directory
23357 @file{/export} is served to all NFS clients as a read-only share:
23363 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
23366 @item @code{rpcmountd-port} (default: @code{#f})
23367 The network port that the @command{rpc.mountd} daemon should use.
23369 @item @code{rpcstatd-port} (default: @code{#f})
23370 The network port that the @command{rpc.statd} daemon should use.
23372 @item @code{rpcbind} (default: @code{rpcbind})
23373 The rpcbind package to use.
23375 @item @code{idmap-domain} (default: @code{"localdomain"})
23376 The local NFSv4 domain name.
23378 @item @code{nfsd-port} (default: @code{2049})
23379 The network port that the @command{nfsd} daemon should use.
23381 @item @code{nfsd-threads} (default: @code{8})
23382 The number of threads used by the @command{nfsd} daemon.
23384 @item @code{nfsd-tcp?} (default: @code{#t})
23385 Whether the @command{nfsd} daemon should listen on a TCP socket.
23387 @item @code{nfsd-udp?} (default: @code{#f})
23388 Whether the @command{nfsd} daemon should listen on a UDP socket.
23390 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
23391 The directory where the pipefs file system is mounted.
23393 @item @code{debug} (default: @code{'()"})
23394 A list of subsystems for which debugging output should be enabled. This
23395 is a list of symbols. Any of these symbols are valid: @code{nfsd},
23396 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
23400 If you don't need a complete NFS service or prefer to build it yourself
23401 you can use the individual component services that are documented below.
23403 @subsubheading RPC Bind Service
23406 The RPC Bind service provides a facility to map program numbers into
23407 universal addresses.
23408 Many NFS related services use this facility. Hence it is automatically
23409 started when a dependent service starts.
23411 @defvr {Scheme Variable} rpcbind-service-type
23412 A service type for the RPC portmapper daemon.
23416 @deftp {Data Type} rpcbind-configuration
23417 Data type representing the configuration of the RPC Bind Service.
23418 This type has the following parameters:
23420 @item @code{rpcbind} (default: @code{rpcbind})
23421 The rpcbind package to use.
23423 @item @code{warm-start?} (default: @code{#t})
23424 If this parameter is @code{#t}, then the daemon will read a
23425 state file on startup thus reloading state information saved by a previous
23431 @subsubheading Pipefs Pseudo File System
23435 The pipefs file system is used to transfer NFS related data
23436 between the kernel and user space programs.
23438 @defvr {Scheme Variable} pipefs-service-type
23439 A service type for the pipefs pseudo file system.
23442 @deftp {Data Type} pipefs-configuration
23443 Data type representing the configuration of the pipefs pseudo file system service.
23444 This type has the following parameters:
23446 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
23447 The directory to which the file system is to be attached.
23452 @subsubheading GSS Daemon Service
23455 @cindex global security system
23457 The @dfn{global security system} (GSS) daemon provides strong security for RPC
23459 Before exchanging RPC requests an RPC client must establish a security
23460 context. Typically this is done using the Kerberos command @command{kinit}
23461 or automatically at login time using PAM services (@pxref{Kerberos Services}).
23463 @defvr {Scheme Variable} gss-service-type
23464 A service type for the Global Security System (GSS) daemon.
23467 @deftp {Data Type} gss-configuration
23468 Data type representing the configuration of the GSS daemon service.
23469 This type has the following parameters:
23471 @item @code{nfs-utils} (default: @code{nfs-utils})
23472 The package in which the @command{rpc.gssd} command is to be found.
23474 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
23475 The directory where the pipefs file system is mounted.
23481 @subsubheading IDMAP Daemon Service
23483 @cindex name mapper
23485 The idmap daemon service provides mapping between user IDs and user names.
23486 Typically it is required in order to access file systems mounted via NFSv4.
23488 @defvr {Scheme Variable} idmap-service-type
23489 A service type for the Identity Mapper (IDMAP) daemon.
23492 @deftp {Data Type} idmap-configuration
23493 Data type representing the configuration of the IDMAP daemon service.
23494 This type has the following parameters:
23496 @item @code{nfs-utils} (default: @code{nfs-utils})
23497 The package in which the @command{rpc.idmapd} command is to be found.
23499 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
23500 The directory where the pipefs file system is mounted.
23502 @item @code{domain} (default: @code{#f})
23503 The local NFSv4 domain name.
23504 This must be a string or @code{#f}.
23505 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
23507 @item @code{verbosity} (default: @code{0})
23508 The verbosity level of the daemon.
23513 @node Continuous Integration
23514 @subsection Continuous Integration
23516 @cindex continuous integration
23517 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
23518 continuous integration tool for Guix. It can be used both for development and
23519 for providing substitutes to others (@pxref{Substitutes}).
23521 The @code{(gnu services cuirass)} module provides the following service.
23523 @defvr {Scheme Procedure} cuirass-service-type
23524 The type of the Cuirass service. Its value must be a
23525 @code{cuirass-configuration} object, as described below.
23528 To add build jobs, you have to set the @code{specifications} field of the
23529 configuration. Here is an example of a service that polls the Guix repository
23530 and builds the packages from a manifest. Some of the packages are defined in
23531 the @code{"custom-packages"} input, which is the equivalent of
23532 @env{GUIX_PACKAGE_PATH}.
23535 (define %cuirass-specs
23537 '((#:name . "my-manifest")
23538 (#:load-path-inputs . ("guix"))
23539 (#:package-path-inputs . ("custom-packages"))
23540 (#:proc-input . "guix")
23541 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
23542 (#:proc . cuirass-jobs)
23543 (#:proc-args . ((subset . "manifests")
23544 (systems . ("x86_64-linux"))
23545 (manifests . (("config" . "guix/manifest.scm")))))
23546 (#:inputs . (((#:name . "guix")
23547 (#:url . "git://git.savannah.gnu.org/guix.git")
23548 (#:load-path . ".")
23549 (#:branch . "master")
23550 (#:no-compile? . #t))
23551 ((#:name . "config")
23552 (#:url . "https://git.example.org/config.git")
23553 (#:load-path . ".")
23554 (#:branch . "master")
23555 (#:no-compile? . #t))
23556 ((#:name . "custom-packages")
23557 (#:url . "https://git.example.org/custom-packages.git")
23558 (#:load-path . ".")
23559 (#:branch . "master")
23560 (#:no-compile? . #t)))))))
23562 (service cuirass-service-type
23563 (cuirass-configuration
23564 (specifications %cuirass-specs)))
23567 While information related to build jobs is located directly in the
23568 specifications, global settings for the @command{cuirass} process are
23569 accessible in other @code{cuirass-configuration} fields.
23571 @deftp {Data Type} cuirass-configuration
23572 Data type representing the configuration of Cuirass.
23575 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
23576 Location of the log file.
23578 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
23579 Location of the log file used by the web interface.
23581 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
23582 Location of the repository cache.
23584 @item @code{user} (default: @code{"cuirass"})
23585 Owner of the @code{cuirass} process.
23587 @item @code{group} (default: @code{"cuirass"})
23588 Owner's group of the @code{cuirass} process.
23590 @item @code{interval} (default: @code{60})
23591 Number of seconds between the poll of the repositories followed by the
23594 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
23595 Location of sqlite database which contains the build results and previously
23596 added specifications.
23598 @item @code{ttl} (default: @code{(* 30 24 3600)})
23599 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
23600 are registered for build results. This means that build results are protected
23601 from garbage collection for at least @var{ttl} seconds.
23603 @item @code{port} (default: @code{8081})
23604 Port number used by the HTTP server.
23606 @item @code{host} (default: @code{"localhost"})
23607 Listen on the network interface for @var{host}. The default is to
23608 accept connections from localhost.
23610 @item @code{specifications} (default: @code{#~'()})
23611 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
23612 where a specification is an association list
23613 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
23614 keys are keywords (@code{#:keyword-example}) as shown in the example
23617 @item @code{use-substitutes?} (default: @code{#f})
23618 This allows using substitutes to avoid building every dependencies of a job
23621 @item @code{one-shot?} (default: @code{#f})
23622 Only evaluate specifications and build derivations once.
23624 @item @code{fallback?} (default: @code{#f})
23625 When substituting a pre-built binary fails, fall back to building
23628 @item @code{extra-options} (default: @code{'()})
23629 Extra options to pass when running the Cuirass processes.
23631 @item @code{cuirass} (default: @code{cuirass})
23632 The Cuirass package to use.
23636 @node Power Management Services
23637 @subsection Power Management Services
23640 @cindex power management with TLP
23641 @subsubheading TLP daemon
23643 The @code{(gnu services pm)} module provides a Guix service definition
23644 for the Linux power management tool TLP.
23646 TLP enables various powersaving modes in userspace and kernel.
23647 Contrary to @code{upower-service}, it is not a passive,
23648 monitoring tool, as it will apply custom settings each time a new power
23649 source is detected. More information can be found at
23650 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
23652 @deffn {Scheme Variable} tlp-service-type
23653 The service type for the TLP tool. The default settings are optimised
23654 for battery life on most systems, but you can tweak them to your heart's
23655 content by adding a valid @code{tlp-configuration}:
23657 (service tlp-service-type
23659 (cpu-scaling-governor-on-ac (list "performance"))
23660 (sched-powersave-on-bat? #t)))
23664 Each parameter definition is preceded by its type; for example,
23665 @samp{boolean foo} indicates that the @code{foo} parameter
23666 should be specified as a boolean. Types starting with
23667 @code{maybe-} denote parameters that won't show up in TLP config file
23668 when their value is @code{'disabled}.
23670 @c The following documentation was initially generated by
23671 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
23672 @c documentation is better, so we shouldn't hesitate to edit below as
23673 @c needed. However if the change you want to make to this documentation
23674 @c can be done in an automated way, it's probably easier to change
23675 @c (generate-documentation) than to make it below and have to deal with
23676 @c the churn as TLP updates.
23678 Available @code{tlp-configuration} fields are:
23680 @deftypevr {@code{tlp-configuration} parameter} package tlp
23685 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
23686 Set to true if you wish to enable TLP.
23688 Defaults to @samp{#t}.
23692 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
23693 Default mode when no power supply can be detected. Alternatives are AC
23696 Defaults to @samp{"AC"}.
23700 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
23701 Number of seconds Linux kernel has to wait after the disk goes idle,
23702 before syncing on AC.
23704 Defaults to @samp{0}.
23708 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
23709 Same as @code{disk-idle-ac} but on BAT mode.
23711 Defaults to @samp{2}.
23715 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
23716 Dirty pages flushing periodicity, expressed in seconds.
23718 Defaults to @samp{15}.
23722 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
23723 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
23725 Defaults to @samp{60}.
23729 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
23730 CPU frequency scaling governor on AC mode. With intel_pstate driver,
23731 alternatives are powersave and performance. With acpi-cpufreq driver,
23732 alternatives are ondemand, powersave, performance and conservative.
23734 Defaults to @samp{disabled}.
23738 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
23739 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
23741 Defaults to @samp{disabled}.
23745 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
23746 Set the min available frequency for the scaling governor on AC.
23748 Defaults to @samp{disabled}.
23752 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
23753 Set the max available frequency for the scaling governor on AC.
23755 Defaults to @samp{disabled}.
23759 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
23760 Set the min available frequency for the scaling governor on BAT.
23762 Defaults to @samp{disabled}.
23766 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
23767 Set the max available frequency for the scaling governor on BAT.
23769 Defaults to @samp{disabled}.
23773 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
23774 Limit the min P-state to control the power dissipation of the CPU, in AC
23775 mode. Values are stated as a percentage of the available performance.
23777 Defaults to @samp{disabled}.
23781 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
23782 Limit the max P-state to control the power dissipation of the CPU, in AC
23783 mode. Values are stated as a percentage of the available performance.
23785 Defaults to @samp{disabled}.
23789 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
23790 Same as @code{cpu-min-perf-on-ac} on BAT mode.
23792 Defaults to @samp{disabled}.
23796 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
23797 Same as @code{cpu-max-perf-on-ac} on BAT mode.
23799 Defaults to @samp{disabled}.
23803 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
23804 Enable CPU turbo boost feature on AC mode.
23806 Defaults to @samp{disabled}.
23810 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
23811 Same as @code{cpu-boost-on-ac?} on BAT mode.
23813 Defaults to @samp{disabled}.
23817 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
23818 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
23819 used under light load conditions.
23821 Defaults to @samp{#f}.
23825 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
23826 Same as @code{sched-powersave-on-ac?} but on BAT mode.
23828 Defaults to @samp{#t}.
23832 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
23833 Enable Linux kernel NMI watchdog.
23835 Defaults to @samp{#f}.
23839 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
23840 For Linux kernels with PHC patch applied, change CPU voltages. An
23841 example value would be @samp{"F:V F:V F:V F:V"}.
23843 Defaults to @samp{disabled}.
23847 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
23848 Set CPU performance versus energy saving policy on AC. Alternatives are
23849 performance, normal, powersave.
23851 Defaults to @samp{"performance"}.
23855 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
23856 Same as @code{energy-perf-policy-ac} but on BAT mode.
23858 Defaults to @samp{"powersave"}.
23862 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
23867 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
23868 Hard disk advanced power management level.
23872 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
23873 Same as @code{disk-apm-bat} but on BAT mode.
23877 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
23878 Hard disk spin down timeout. One value has to be specified for each
23879 declared hard disk.
23881 Defaults to @samp{disabled}.
23885 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
23886 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
23888 Defaults to @samp{disabled}.
23892 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
23893 Select IO scheduler for disk devices. One value has to be specified for
23894 each declared hard disk. Example alternatives are cfq, deadline and
23897 Defaults to @samp{disabled}.
23901 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
23902 SATA aggressive link power management (ALPM) level. Alternatives are
23903 min_power, medium_power, max_performance.
23905 Defaults to @samp{"max_performance"}.
23909 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
23910 Same as @code{sata-linkpwr-ac} but on BAT mode.
23912 Defaults to @samp{"min_power"}.
23916 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
23917 Exclude specified SATA host devices for link power management.
23919 Defaults to @samp{disabled}.
23923 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
23924 Enable Runtime Power Management for AHCI controller and disks on AC
23927 Defaults to @samp{disabled}.
23931 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
23932 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
23934 Defaults to @samp{disabled}.
23938 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
23939 Seconds of inactivity before disk is suspended.
23941 Defaults to @samp{15}.
23945 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
23946 PCI Express Active State Power Management level. Alternatives are
23947 default, performance, powersave.
23949 Defaults to @samp{"performance"}.
23953 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
23954 Same as @code{pcie-aspm-ac} but on BAT mode.
23956 Defaults to @samp{"powersave"}.
23960 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
23961 Radeon graphics clock speed level. Alternatives are low, mid, high,
23964 Defaults to @samp{"high"}.
23968 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
23969 Same as @code{radeon-power-ac} but on BAT mode.
23971 Defaults to @samp{"low"}.
23975 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
23976 Radeon dynamic power management method (DPM). Alternatives are battery,
23979 Defaults to @samp{"performance"}.
23983 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
23984 Same as @code{radeon-dpm-state-ac} but on BAT mode.
23986 Defaults to @samp{"battery"}.
23990 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
23991 Radeon DPM performance level. Alternatives are auto, low, high.
23993 Defaults to @samp{"auto"}.
23997 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
23998 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
24000 Defaults to @samp{"auto"}.
24004 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
24005 Wifi power saving mode.
24007 Defaults to @samp{#f}.
24011 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
24012 Same as @code{wifi-power-ac?} but on BAT mode.
24014 Defaults to @samp{#t}.
24018 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
24019 Disable wake on LAN.
24021 Defaults to @samp{#t}.
24025 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
24026 Timeout duration in seconds before activating audio power saving on
24027 Intel HDA and AC97 devices. A value of 0 disables power saving.
24029 Defaults to @samp{0}.
24033 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
24034 Same as @code{sound-powersave-ac} but on BAT mode.
24036 Defaults to @samp{1}.
24040 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
24041 Disable controller in powersaving mode on Intel HDA devices.
24043 Defaults to @samp{#t}.
24047 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
24048 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
24049 powered on again by releasing (and reinserting) the eject lever or by
24050 pressing the disc eject button on newer models.
24052 Defaults to @samp{#f}.
24056 @deftypevr {@code{tlp-configuration} parameter} string bay-device
24057 Name of the optical drive device to power off.
24059 Defaults to @samp{"sr0"}.
24063 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
24064 Runtime Power Management for PCI(e) bus devices. Alternatives are on
24067 Defaults to @samp{"on"}.
24071 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
24072 Same as @code{runtime-pm-ac} but on BAT mode.
24074 Defaults to @samp{"auto"}.
24078 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
24079 Runtime Power Management for all PCI(e) bus devices, except blacklisted
24082 Defaults to @samp{#t}.
24086 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
24087 Exclude specified PCI(e) device addresses from Runtime Power Management.
24089 Defaults to @samp{disabled}.
24093 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
24094 Exclude PCI(e) devices assigned to the specified drivers from Runtime
24099 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
24100 Enable USB autosuspend feature.
24102 Defaults to @samp{#t}.
24106 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
24107 Exclude specified devices from USB autosuspend.
24109 Defaults to @samp{disabled}.
24113 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
24114 Exclude WWAN devices from USB autosuspend.
24116 Defaults to @samp{#t}.
24120 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
24121 Include specified devices into USB autosuspend, even if they are already
24122 excluded by the driver or via @code{usb-blacklist-wwan?}.
24124 Defaults to @samp{disabled}.
24128 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
24129 Enable USB autosuspend before shutdown.
24131 Defaults to @samp{disabled}.
24135 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
24136 Restore radio device state (bluetooth, wifi, wwan) from previous
24137 shutdown on system startup.
24139 Defaults to @samp{#f}.
24144 @cindex CPU frequency scaling with thermald
24145 @subsubheading Thermald daemon
24147 The @code{(gnu services pm)} module provides an interface to
24148 thermald, a CPU frequency scaling service which helps prevent overheating.
24150 @defvr {Scheme Variable} thermald-service-type
24151 This is the service type for
24152 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
24153 Thermal Daemon, which is responsible for controlling the thermal state
24154 of processors and preventing overheating.
24157 @deftp {Data Type} thermald-configuration
24158 Data type representing the configuration of @code{thermald-service-type}.
24161 @item @code{ignore-cpuid-check?} (default: @code{#f})
24162 Ignore cpuid check for supported CPU models.
24164 @item @code{thermald} (default: @var{thermald})
24165 Package object of thermald.
24170 @node Audio Services
24171 @subsection Audio Services
24173 The @code{(gnu services audio)} module provides a service to start MPD
24174 (the Music Player Daemon).
24177 @subsubheading Music Player Daemon
24179 The Music Player Daemon (MPD) is a service that can play music while
24180 being controlled from the local machine or over the network by a variety
24183 The following example shows how one might run @code{mpd} as user
24184 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
24187 (service mpd-service-type
24193 @defvr {Scheme Variable} mpd-service-type
24194 The service type for @command{mpd}
24197 @deftp {Data Type} mpd-configuration
24198 Data type representing the configuration of @command{mpd}.
24201 @item @code{user} (default: @code{"mpd"})
24202 The user to run mpd as.
24204 @item @code{music-dir} (default: @code{"~/Music"})
24205 The directory to scan for music files.
24207 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
24208 The directory to store playlists.
24210 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
24211 The location of the music database.
24213 @item @code{state-file} (default: @code{"~/.mpd/state"})
24214 The location of the file that stores current MPD's state.
24216 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
24217 The location of the sticker database.
24219 @item @code{port} (default: @code{"6600"})
24220 The port to run mpd on.
24222 @item @code{address} (default: @code{"any"})
24223 The address that mpd will bind to. To use a Unix domain socket,
24224 an absolute path can be specified here.
24226 @item @code{outputs} (default: @code{"(list (mpd-output))"})
24227 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
24232 @deftp {Data Type} mpd-output
24233 Data type representing an @command{mpd} audio output.
24236 @item @code{name} (default: @code{"MPD"})
24237 The name of the audio output.
24239 @item @code{type} (default: @code{"pulse"})
24240 The type of audio output.
24242 @item @code{enabled?} (default: @code{#t})
24243 Specifies whether this audio output is enabled when MPD is started. By
24244 default, all audio outputs are enabled. This is just the default
24245 setting when there is no state file; with a state file, the previous
24248 @item @code{tags?} (default: @code{#t})
24249 If set to @code{#f}, then MPD will not send tags to this output. This
24250 is only useful for output plugins that can receive tags, for example the
24251 @code{httpd} output plugin.
24253 @item @code{always-on?} (default: @code{#f})
24254 If set to @code{#t}, then MPD attempts to keep this audio output always
24255 open. This may be useful for streaming servers, when you don’t want to
24256 disconnect all listeners even when playback is accidentally stopped.
24258 @item @code{mixer-type}
24259 This field accepts a symbol that specifies which mixer should be used
24260 for this audio output: the @code{hardware} mixer, the @code{software}
24261 mixer, the @code{null} mixer (allows setting the volume, but with no
24262 effect; this can be used as a trick to implement an external mixer
24263 External Mixer) or no mixer (@code{none}).
24265 @item @code{extra-options} (default: @code{'()"})
24266 An association list of option symbols to string values to be appended to
24267 the audio output configuration.
24272 The following example shows a configuration of @code{mpd} that provides
24273 an HTTP audio streaming output.
24276 (service mpd-service-type
24284 `((encoder . "vorbis")
24285 (port . "8080"))))))))
24289 @node Virtualization Services
24290 @subsection Virtualization services
24292 The @code{(gnu services virtualization)} module provides services for
24293 the libvirt and virtlog daemons, as well as other virtualization-related
24296 @subsubheading Libvirt daemon
24297 @code{libvirtd} is the server side daemon component of the libvirt
24298 virtualization management system. This daemon runs on host servers
24299 and performs required management tasks for virtualized guests.
24301 @deffn {Scheme Variable} libvirt-service-type
24302 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
24303 Its value must be a @code{libvirt-configuration}.
24306 (service libvirt-service-type
24307 (libvirt-configuration
24308 (unix-sock-group "libvirt")
24309 (tls-port "16555")))
24313 @c Auto-generated with (generate-libvirt-documentation)
24314 Available @code{libvirt-configuration} fields are:
24316 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
24321 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
24322 Flag listening for secure TLS connections on the public TCP/IP port.
24323 must set @code{listen} for this to have any effect.
24325 It is necessary to setup a CA and issue server certificates before using
24328 Defaults to @samp{#t}.
24332 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
24333 Listen for unencrypted TCP connections on the public TCP/IP port. must
24334 set @code{listen} for this to have any effect.
24336 Using the TCP socket requires SASL authentication by default. Only SASL
24337 mechanisms which support data encryption are allowed. This is
24338 DIGEST_MD5 and GSSAPI (Kerberos5)
24340 Defaults to @samp{#f}.
24344 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
24345 Port for accepting secure TLS connections This can be a port number, or
24348 Defaults to @samp{"16514"}.
24352 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
24353 Port for accepting insecure TCP connections This can be a port number,
24356 Defaults to @samp{"16509"}.
24360 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
24361 IP address or hostname used for client connections.
24363 Defaults to @samp{"0.0.0.0"}.
24367 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
24368 Flag toggling mDNS advertisement of the libvirt service.
24370 Alternatively can disable for all services on a host by stopping the
24373 Defaults to @samp{#f}.
24377 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
24378 Default mDNS advertisement name. This must be unique on the immediate
24381 Defaults to @samp{"Virtualization Host <hostname>"}.
24385 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
24386 UNIX domain socket group ownership. This can be used to allow a
24387 'trusted' set of users access to management capabilities without
24390 Defaults to @samp{"root"}.
24394 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
24395 UNIX socket permissions for the R/O socket. This is used for monitoring
24398 Defaults to @samp{"0777"}.
24402 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
24403 UNIX socket permissions for the R/W socket. Default allows only root.
24404 If PolicyKit is enabled on the socket, the default will change to allow
24405 everyone (eg, 0777)
24407 Defaults to @samp{"0770"}.
24411 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
24412 UNIX socket permissions for the admin socket. Default allows only owner
24413 (root), do not change it unless you are sure to whom you are exposing
24416 Defaults to @samp{"0777"}.
24420 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
24421 The directory in which sockets will be found/created.
24423 Defaults to @samp{"/var/run/libvirt"}.
24427 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
24428 Authentication scheme for UNIX read-only sockets. By default socket
24429 permissions allow anyone to connect
24431 Defaults to @samp{"polkit"}.
24435 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
24436 Authentication scheme for UNIX read-write sockets. By default socket
24437 permissions only allow root. If PolicyKit support was compiled into
24438 libvirt, the default will be to use 'polkit' auth.
24440 Defaults to @samp{"polkit"}.
24444 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
24445 Authentication scheme for TCP sockets. If you don't enable SASL, then
24446 all TCP traffic is cleartext. Don't do this outside of a dev/test
24449 Defaults to @samp{"sasl"}.
24453 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
24454 Authentication scheme for TLS sockets. TLS sockets already have
24455 encryption provided by the TLS layer, and limited authentication is done
24458 It is possible to make use of any SASL authentication mechanism as well,
24459 by using 'sasl' for this option
24461 Defaults to @samp{"none"}.
24465 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
24466 API access control scheme.
24468 By default an authenticated user is allowed access to all APIs. Access
24469 drivers can place restrictions on this.
24471 Defaults to @samp{()}.
24475 @deftypevr {@code{libvirt-configuration} parameter} string key-file
24476 Server key file path. If set to an empty string, then no private key is
24479 Defaults to @samp{""}.
24483 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
24484 Server key file path. If set to an empty string, then no certificate is
24487 Defaults to @samp{""}.
24491 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
24492 Server key file path. If set to an empty string, then no CA certificate
24495 Defaults to @samp{""}.
24499 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
24500 Certificate revocation list path. If set to an empty string, then no
24503 Defaults to @samp{""}.
24507 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
24508 Disable verification of our own server certificates.
24510 When libvirtd starts it performs some sanity checks against its own
24513 Defaults to @samp{#f}.
24517 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
24518 Disable verification of client certificates.
24520 Client certificate verification is the primary authentication mechanism.
24521 Any client which does not present a certificate signed by the CA will be
24524 Defaults to @samp{#f}.
24528 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
24529 Whitelist of allowed x509 Distinguished Name.
24531 Defaults to @samp{()}.
24535 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
24536 Whitelist of allowed SASL usernames. The format for username depends on
24537 the SASL authentication mechanism.
24539 Defaults to @samp{()}.
24543 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
24544 Override the compile time default TLS priority string. The default is
24545 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
24546 is desired for libvirt to deviate from the global default settings.
24548 Defaults to @samp{"NORMAL"}.
24552 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
24553 Maximum number of concurrent client connections to allow over all
24556 Defaults to @samp{5000}.
24560 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
24561 Maximum length of queue of connections waiting to be accepted by the
24562 daemon. Note, that some protocols supporting retransmission may obey
24563 this so that a later reattempt at connection succeeds.
24565 Defaults to @samp{1000}.
24569 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
24570 Maximum length of queue of accepted but not yet authenticated clients.
24571 Set this to zero to turn this feature off
24573 Defaults to @samp{20}.
24577 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
24578 Number of workers to start up initially.
24580 Defaults to @samp{5}.
24584 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
24585 Maximum number of worker threads.
24587 If the number of active clients exceeds @code{min-workers}, then more
24588 threads are spawned, up to max_workers limit. Typically you'd want
24589 max_workers to equal maximum number of clients allowed.
24591 Defaults to @samp{20}.
24595 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
24596 Number of priority workers. If all workers from above pool are stuck,
24597 some calls marked as high priority (notably domainDestroy) can be
24598 executed in this pool.
24600 Defaults to @samp{5}.
24604 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
24605 Total global limit on concurrent RPC calls.
24607 Defaults to @samp{20}.
24611 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
24612 Limit on concurrent requests from a single client connection. To avoid
24613 one client monopolizing the server this should be a small fraction of
24614 the global max_requests and max_workers parameter.
24616 Defaults to @samp{5}.
24620 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
24621 Same as @code{min-workers} but for the admin interface.
24623 Defaults to @samp{1}.
24627 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
24628 Same as @code{max-workers} but for the admin interface.
24630 Defaults to @samp{5}.
24634 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
24635 Same as @code{max-clients} but for the admin interface.
24637 Defaults to @samp{5}.
24641 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
24642 Same as @code{max-queued-clients} but for the admin interface.
24644 Defaults to @samp{5}.
24648 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
24649 Same as @code{max-client-requests} but for the admin interface.
24651 Defaults to @samp{5}.
24655 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
24656 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
24658 Defaults to @samp{3}.
24662 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
24665 A filter allows to select a different logging level for a given category
24666 of logs The format for a filter is one of:
24677 where @code{name} is a string which is matched against the category
24678 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
24679 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
24680 name in the filter can be a substring of the full category name, in
24681 order to match multiple similar categories), the optional @samp{"+"}
24682 prefix tells libvirt to log stack trace for each message matching name,
24683 and @code{x} is the minimal level where matching messages should be
24701 Multiple filters can be defined in a single filters statement, they just
24702 need to be separated by spaces.
24704 Defaults to @samp{"3:remote 4:event"}.
24708 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
24711 An output is one of the places to save logging information. The format
24712 for an output can be:
24716 output goes to stderr
24718 @item x:syslog:name
24719 use syslog for the output and use the given name as the ident
24721 @item x:file:file_path
24722 output to a file, with the given filepath
24725 output to journald logging system
24729 In all case the x prefix is the minimal level, acting as a filter
24746 Multiple outputs can be defined, they just need to be separated by
24749 Defaults to @samp{"3:stderr"}.
24753 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
24754 Allows usage of the auditing subsystem to be altered
24758 0: disable all auditing
24761 1: enable auditing, only if enabled on host
24764 2: enable auditing, and exit if disabled on host.
24768 Defaults to @samp{1}.
24772 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
24773 Send audit messages via libvirt logging infrastructure.
24775 Defaults to @samp{#f}.
24779 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
24780 Host UUID. UUID must not have all digits be the same.
24782 Defaults to @samp{""}.
24786 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
24787 Source to read host UUID.
24791 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
24794 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
24798 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
24801 Defaults to @samp{"smbios"}.
24805 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
24806 A keepalive message is sent to a client after @code{keepalive_interval}
24807 seconds of inactivity to check if the client is still responding. If
24808 set to -1, libvirtd will never send keepalive requests; however clients
24809 can still send them and the daemon will send responses.
24811 Defaults to @samp{5}.
24815 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
24816 Maximum number of keepalive messages that are allowed to be sent to the
24817 client without getting any response before the connection is considered
24820 In other words, the connection is automatically closed approximately
24821 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
24822 the last message received from the client. When @code{keepalive-count}
24823 is set to 0, connections will be automatically closed after
24824 @code{keepalive-interval} seconds of inactivity without sending any
24825 keepalive messages.
24827 Defaults to @samp{5}.
24831 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
24832 Same as above but for admin interface.
24834 Defaults to @samp{5}.
24838 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
24839 Same as above but for admin interface.
24841 Defaults to @samp{5}.
24845 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
24846 Timeout for Open vSwitch calls.
24848 The @code{ovs-vsctl} utility is used for the configuration and its
24849 timeout option is set by default to 5 seconds to avoid potential
24850 infinite waits blocking libvirt.
24852 Defaults to @samp{5}.
24856 @c %end of autogenerated docs
24858 @subsubheading Virtlog daemon
24859 The virtlogd service is a server side daemon component of libvirt that is
24860 used to manage logs from virtual machine consoles.
24862 This daemon is not used directly by libvirt client applications, rather it
24863 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
24864 standalone daemon, the main @code{libvirtd} daemon can be restarted without
24865 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
24866 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
24868 @deffn {Scheme Variable} virtlog-service-type
24869 This is the type of the virtlog daemon.
24870 Its value must be a @code{virtlog-configuration}.
24873 (service virtlog-service-type
24874 (virtlog-configuration
24875 (max-clients 1000)))
24879 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
24880 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
24882 Defaults to @samp{3}.
24886 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
24889 A filter allows to select a different logging level for a given category
24890 of logs The format for a filter is one of:
24901 where @code{name} is a string which is matched against the category
24902 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
24903 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
24904 be a substring of the full category name, in order to match multiple
24905 similar categories), the optional "+" prefix tells libvirt to log stack
24906 trace for each message matching name, and @code{x} is the minimal level
24907 where matching messages should be logged:
24924 Multiple filters can be defined in a single filters statement, they just
24925 need to be separated by spaces.
24927 Defaults to @samp{"3:remote 4:event"}.
24931 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
24934 An output is one of the places to save logging information The format
24935 for an output can be:
24939 output goes to stderr
24941 @item x:syslog:name
24942 use syslog for the output and use the given name as the ident
24944 @item x:file:file_path
24945 output to a file, with the given filepath
24948 output to journald logging system
24952 In all case the x prefix is the minimal level, acting as a filter
24969 Multiple outputs can be defined, they just need to be separated by
24972 Defaults to @samp{"3:stderr"}.
24976 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
24977 Maximum number of concurrent client connections to allow over all
24980 Defaults to @samp{1024}.
24984 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
24985 Maximum file size before rolling over.
24987 Defaults to @samp{2MB}
24991 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
24992 Maximum number of backup files to keep.
24994 Defaults to @samp{3}
24998 @subsubheading Transparent Emulation with QEMU
25001 @cindex @code{binfmt_misc}
25002 @code{qemu-binfmt-service-type} provides support for transparent
25003 emulation of program binaries built for different architectures---e.g.,
25004 it allows you to transparently execute an ARMv7 program on an x86_64
25005 machine. It achieves this by combining the @uref{https://www.qemu.org,
25006 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
25008 @defvr {Scheme Variable} qemu-binfmt-service-type
25009 This is the type of the QEMU/binfmt service for transparent emulation.
25010 Its value must be a @code{qemu-binfmt-configuration} object, which
25011 specifies the QEMU package to use as well as the architecture we want to
25015 (service qemu-binfmt-service-type
25016 (qemu-binfmt-configuration
25017 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
25020 In this example, we enable transparent emulation for the ARM and aarch64
25021 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
25022 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
25023 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
25026 @deftp {Data Type} qemu-binfmt-configuration
25027 This is the configuration for the @code{qemu-binfmt} service.
25030 @item @code{platforms} (default: @code{'()})
25031 The list of emulated QEMU platforms. Each item must be a @dfn{platform
25032 object} as returned by @code{lookup-qemu-platforms} (see below).
25034 @item @code{guix-support?} (default: @code{#f})
25035 When it is true, QEMU and all its dependencies are added to the build
25036 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
25037 @option{--chroot-directory} option}). This allows the @code{binfmt_misc}
25038 handlers to be used within the build environment, which in turn means
25039 that you can transparently build programs for another architecture.
25041 For example, let's suppose you're on an x86_64 machine and you have this
25045 (service qemu-binfmt-service-type
25046 (qemu-binfmt-configuration
25047 (platforms (lookup-qemu-platforms "arm"))
25048 (guix-support? #t)))
25054 guix build -s armhf-linux inkscape
25058 and it will build Inkscape for ARMv7 @emph{as if it were a native
25059 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
25060 if you'd like to test a package build for an architecture you don't have
25063 @item @code{qemu} (default: @code{qemu})
25064 The QEMU package to use.
25068 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
25069 Return the list of QEMU platform objects corresponding to
25070 @var{platforms}@dots{}. @var{platforms} must be a list of strings
25071 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
25072 @code{"mips64el"}, and so on.
25075 @deffn {Scheme Procedure} qemu-platform? @var{obj}
25076 Return true if @var{obj} is a platform object.
25079 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
25080 Return the name of @var{platform}---a string such as @code{"arm"}.
25084 @subsubheading The Hurd in a Virtual Machine
25086 @cindex @code{hurd}
25089 Service @code{hurd-vm} provides support for running GNU/Hurd in a
25090 virtual machine (VM), a so-called ``Childhurd''. The virtual machine is
25091 a Shepherd service that can be referred to by the names @code{hurd-vm}
25092 and @code{childhurd} and be controlled with commands such as:
25096 herd stop childhurd
25099 The given GNU/Hurd operating system configuration is cross-compiled.
25101 @defvr {Scheme Variable} hurd-vm-service-type
25102 This is the type of the Hurd in a Virtual Machine service. Its value
25103 must be a @code{hurd-vm-configuration} object, which specifies the
25104 operating system (@pxref{operating-system Reference}) and the disk size
25105 for the Hurd Virtual Machine, the QEMU package to use as well as the
25106 options for running it.
25111 (service hurd-vm-service-type
25112 (hurd-vm-configuration
25113 (disk-size (* 5000 (expt 2 20))) ;5G
25114 (memory-size 1024))) ;1024MiB
25117 would create a disk image big enough to build GNU@tie{}Hello, with some
25121 @deftp {Data Type} hurd-vm-configuration
25122 The data type representing the configuration for
25123 @code{hurd-vm-service-type}.
25126 @item @code{os} (default: @var{%hurd-vm-operating-system})
25127 The operating system to instantiate. This default is bare-bones with a
25128 permissive OpenSSH secure shell daemon listening on port 2222
25129 (@pxref{Networking Services, @code{openssh-service-type}}).
25131 @item @code{qemu} (default: @code{qemu-minimal})
25132 The QEMU package to use.
25134 @item @code{image} (default: @var{hurd-vm-disk-image})
25135 The procedure used to build the disk-image built from this
25138 @item @code{disk-size} (default: @code{'guess})
25139 The size of the disk image.
25141 @item @code{memory-size} (default: @code{512})
25142 The memory size of the Virtual Machine in mebibytes.
25144 @item @code{options} (default: @code{'("--snapshot")})
25145 The extra options for running QEMU.
25147 @item @code{id} (default: @code{#f})
25148 If set, a non-zero positive integer used to parameterize Childhurd
25149 instances. It is appended to the service's name,
25150 e.g. @code{childhurd1}.
25152 @item @code{net-options} (default: @var{hurd-vm-net-options})
25153 The procedure used to produce the list of QEMU networking options.
25155 By default, it produces
25158 '("--device" "rtl8139,netdev=net0"
25159 "--netdev" "user,id=net0\
25160 ,hostfwd=tcp:127.0.0.1:<ssh-port>-:2222\
25161 ,hostfwd=tcp:127.0.0.1:<vnc-port>-:5900")
25163 with forwarded ports
25165 <ssh-port>: @code{(+ 10022 (* 1000 @var{ID}))}
25166 <vnc-port>: @code{(+ 15900 (* 1000 @var{ID}))}
25172 Note that by default the VM image is volatile, i.e., once stopped the
25173 contents are lost. If you want a stateful image instead, override the
25174 configuration's @code{image} and @code{options} without
25175 the @code{--snapshot} flag using something along these lines:
25178 (service hurd-vm-service-type
25179 (hurd-vm-configuration
25180 (image (const "/out/of/store/writable/hurd.img"))
25181 (options '("--hda"))))
25184 @subsubheading Ganeti
25189 This service is considered experimental. Configuration options may be changed
25190 in a backwards-incompatible manner, and not all features have been thorougly
25191 tested. Users of this service are encouraged to share their experience at
25192 @email{guix-devel@@gnu.org}.
25195 Ganeti is a virtual machine management system. It is designed to keep virtual
25196 machines running on a cluster of servers even in the event of hardware failures,
25197 and to make maintenance and recovery tasks easy. It consists of multiple
25198 services which are described later in this section. In addition to the Ganeti
25199 service, you will need the OpenSSH service (@pxref{Networking Services,
25200 @code{openssh-service-type}}), and update the @file{/etc/hosts} file
25201 (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
25202 and address (or use a DNS server).
25204 All nodes participating in a Ganeti cluster should have the same Ganeti and
25205 @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
25206 cluster node that supports multiple storage backends, and installs the
25207 @code{debootstrap} and @code{guix} @dfn{OS providers}:
25210 (use-package-modules virtualization)
25211 (use-service-modules base ganeti networking ssh)
25214 (host-name "node1")
25215 (hosts-file (plain-file "hosts" (format #f "
25216 127.0.0.1 localhost
25219 192.168.1.200 ganeti.example.com
25220 192.168.1.201 node1.example.com node1
25221 192.168.1.202 node2.example.com node2
25224 ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
25225 ;; in order to use the "plain", "drbd" and "rbd" storage backends.
25226 (packages (append (map specification->package
25227 '("qemu" "lvm2" "drbd-utils" "ceph"
25228 ;; Add the debootstrap and guix OS providers.
25229 "ganeti-instance-guix" "ganeti-instance-debootstrap"))
25232 (append (list (static-networking-service "eth0" "192.168.1.201"
25233 #:netmask "255.255.255.0"
25234 #:gateway "192.168.1.254"
25235 #:name-servers '("192.168.1.252"
25238 ;; Ganeti uses SSH to communicate between nodes.
25239 (service openssh-service-type
25240 (openssh-configuration
25241 (permit-root-login 'without-password)))
25243 (service ganeti-service-type
25244 (ganeti-configuration
25245 ;; This list specifies allowed file system paths
25246 ;; for storing virtual machine images.
25247 (file-storage-paths '("/srv/ganeti/file-storage"))
25248 ;; This variable configures a single "variant" for
25249 ;; both Debootstrap and Guix that works with KVM.
25250 (os %default-ganeti-os))))
25254 Users are advised to read the
25255 @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
25256 administrators guide} to learn about the various cluster options and
25257 day-to-day operations. There is also a
25258 @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
25259 describing how to configure and initialize a small cluster.
25261 @defvr {Scheme Variable} ganeti-service-type
25262 This is a service type that includes all the various services that Ganeti
25265 Its value is a @code{ganeti-configuration} object that defines the package
25266 to use for CLI operations, as well as configuration for the various daemons.
25267 Allowed file storage paths and available guest operating systems are also
25268 configured through this data type.
25271 @deftp {Data Type} ganeti-configuration
25272 The @code{ganeti} service takes the following configuration options:
25275 @item @code{ganeti} (default: @code{ganeti})
25276 The @code{ganeti} package to use. It will be installed to the system profile
25277 and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
25278 that the value specified here does not affect the other services as each refer
25279 to a specific @code{ganeti} package (see below).
25281 @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
25282 @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
25283 @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
25284 @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
25285 @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
25286 @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
25287 @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
25288 @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
25289 @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
25290 @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
25292 These options control the various daemons and cron jobs that are distributed
25293 with Ganeti. The possible values for these are described in detail below.
25294 To override a setting, you must use the configuration type for that service:
25297 (service ganeti-service-type
25298 (ganeti-configuration
25299 (rapi-configuration
25300 (ganeti-rapi-configuration
25301 (interface "eth1"))))
25302 (watcher-configuration
25303 (ganeti-watcher-configuration
25304 (rapi-ip "10.0.0.1"))))
25307 @item @code{file-storage-paths} (default: @code{'()})
25308 List of allowed directories for file storage backend.
25310 @item @code{os} (default: @code{%default-ganeti-os})
25311 List of @code{<ganeti-os>} records.
25314 In essence @code{ganeti-service-type} is shorthand for declaring each service
25318 (service ganeti-noded-service-type)
25319 (service ganeti-confd-service-type)
25320 (service ganeti-wconfd-service-type)
25321 (service ganeti-luxid-service-type)
25322 (service ganeti-kvmd-service-type)
25323 (service ganeti-mond-service-type)
25324 (service ganeti-metad-service-type)
25325 (service ganeti-watcher-service-type)
25326 (service ganeti-cleaner-service-type)
25329 Plus a service extension for @code{etc-service-type} that configures the file
25330 storage backend and OS variants.
25334 @deftp {Data Type} ganeti-os
25335 This data type is suitable for passing to the @code{os} parameter of
25336 @code{ganeti-configuration}. It takes the following parameters:
25340 The name for this OS provider. It is only used to specify where the
25341 configuration ends up. Setting it to ``debootstrap'' will create
25342 @file{/etc/ganeti/instance-debootstrap}.
25344 @item @code{extension}
25345 The file extension for variants of this OS type. For example
25346 @file{.conf} or @file{.scm}.
25348 @item @code{variants} (default: @code{'()})
25349 List of @code{ganeti-os-variant} objects for this OS.
25354 @deftp {Data Type} ganeti-os-variant
25355 This is the data type for a Ganeti OS variant. It takes the following
25360 The name of this variant.
25362 @item @code{configuration}
25363 A configuration file for this variant.
25367 @defvr {Scheme Variable} %default-debootstrap-hooks
25368 This variable contains hooks to configure networking and the GRUB bootloader.
25371 @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
25372 This variable contains a list of packages suitable for a fully-virtualized guest.
25375 @deftp {Data Type} debootstrap-configuration
25377 This data type creates configuration files suitable for the debootstrap OS provider.
25380 @item @code{hooks} (default: @code{%default-debootstrap-hooks})
25381 When not @code{#f}, this must be a G-expression that specifies a directory with
25382 scripts that will run when the OS is installed. It can also be a list of
25383 @code{(name . file-like)} pairs. For example:
25386 `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
25389 That will create a directory with one executable named @code{99-hello-world}
25390 and run it every time this variant is installed. If set to @code{#f}, hooks
25391 in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
25392 @item @code{proxy} (default: @code{#f})
25393 Optional HTTP proxy to use.
25394 @item @code{mirror} (default: @code{#f})
25395 The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
25396 The default varies depending on the distribution.
25397 @item @code{arch} (default: @code{#f})
25398 The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
25399 on an AArch64 host. Default is to use the current system architecture.
25400 @item @code{suite} (default: @code{"stable"})
25401 When set, this must be a Debian distribution ``suite'' such as @code{buster}
25402 or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
25403 @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
25404 List of extra packages that will get installed by dpkg in addition
25405 to the minimal system.
25406 @item @code{components} (default: @code{#f})
25407 When set, must be a list of Debian repository ``components''. For example
25408 @code{'("main" "contrib")}.
25409 @item @code{generate-cache?} (default: @code{#t})
25410 Whether to automatically cache the generated debootstrap archive.
25411 @item @code{clean-cache} (default: @code{14})
25412 Discard the cache after this amount of days. Use @code{#f} to never
25414 @item @code{partition-style} (default: @code{'msdos})
25415 The type of partition to create. When set, it must be one of
25416 @code{'msdos}, @code{'none} or a string.
25417 @item @code{partition-alignment} (default: @code{2048})
25418 Alignment of the partition in sectors.
25422 @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
25423 This is a helper procedure that creates a @code{ganeti-os-variant} record. It
25424 takes two parameters: a name and a @code{debootstrap-configuration} object.
25427 @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
25428 This is a helper procedure that creates a @code{ganeti-os} record. It takes
25429 a list of variants created with @code{debootstrap-variant}.
25432 @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
25433 This is a helper procedure that creates a @code{ganeti-os-variant} record for
25434 use with the Guix OS provider. It takes a name and a G-expression that returns
25435 a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
25436 Guix System configuration.
25439 @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
25440 This is a helper procedure that creates a @code{ganeti-os} record. It
25441 takes a list of variants produced by @code{guix-variant}.
25444 @defvr {Scheme Variable} %default-debootstrap-variants
25445 This is a convenience variable to make the debootstrap provider work
25446 ``out of the box'' without users having to declare variants manually. It
25447 contains a single debootstrap variant with the default configuration:
25450 (list (debootstrap-variant
25452 (debootstrap-configuration)))
25456 @defvr {Scheme Variable} %default-guix-variants
25457 This is a convenience variable to make the Guix OS provider work without
25458 additional configuration. It creates a virtual machine that has an SSH
25459 server, a serial console, and authorizes the Ganeti hosts SSH keys.
25462 (list (guix-variant
25464 (file-append ganeti-instance-guix
25465 "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
25469 Users can implement support for OS providers unbeknownst to Guix by extending
25470 the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
25476 (extension ".conf")
25478 (list (ganeti-os-variant
25480 (configuration (plain-file "bar" "this is fine"))))))
25483 That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
25484 to a file in the store with contents @code{this is fine}. It also creates
25485 @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
25487 Obviously this may not work for all OS providers out there. If you find the
25488 interface limiting, please reach out to @email{guix-devel@@gnu.org}.
25490 The rest of this section documents the various services that are included by
25491 @code{ganeti-service-type}.
25493 @defvr {Scheme Variable} ganeti-noded-service-type
25494 @command{ganeti-noded} is the daemon responsible for node-specific functions
25495 within the Ganeti system. The value of this service must be a
25496 @code{ganeti-noded-configuration} object.
25499 @deftp {Data Type} ganeti-noded-configuration
25500 This is the configuration for the @code{ganeti-noded} service.
25503 @item @code{ganeti} (default: @code{ganeti})
25504 The @code{ganeti} package to use for this service.
25506 @item @code{port} (default: @code{1811})
25507 The TCP port on which the node daemon listens for network requests.
25509 @item @code{address} (default: @code{"0.0.0.0"})
25510 The network address that the daemon will bind to. The default address means
25511 bind to all available addresses.
25513 @item @code{interface} (default: @code{#f})
25514 When this is set, it must be a specific network interface (e.g.@: @code{eth0})
25515 that the daemon will bind to.
25517 @item @code{max-clients} (default: @code{20})
25518 This sets a limit on the maximum number of simultaneous client connections
25519 that the daemon will handle. Connections above this count are accepted, but
25520 no responses will be sent until enough connections have closed.
25522 @item @code{ssl?} (default: @code{#t})
25523 Whether to use SSL/TLS to encrypt network communications. The certificate
25524 is automatically provisioned by the cluster and can be rotated with
25525 @command{gnt-cluster renew-crypto}.
25527 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
25528 This can be used to provide a specific encryption key for TLS communications.
25530 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
25531 This can be used to provide a specific certificate for TLS communications.
25533 @item @code{debug?} (default: @code{#f})
25534 When true, the daemon performs additional logging for debugging purposes.
25535 Note that this will leak encryption details to the log files, use with caution.
25540 @defvr {Scheme Variable} ganeti-confd-service-type
25541 @command{ganeti-confd} answers queries related to the configuration of a
25542 Ganeti cluster. The purpose of this daemon is to have a highly available
25543 and fast way to query cluster configuration values. It is automatically
25544 active on all @dfn{master candidates}. The value of this service must be a
25545 @code{ganeti-confd-configuration} object.
25549 @deftp {Data Type} ganeti-confd-configuration
25550 This is the configuration for the @code{ganeti-confd} service.
25553 @item @code{ganeti} (default: @code{ganeti})
25554 The @code{ganeti} package to use for this service.
25556 @item @code{port} (default: @code{1814})
25557 The UDP port on which to listen for network requests.
25559 @item @code{address} (default: @code{"0.0.0.0"})
25560 Network address that the daemon will bind to.
25562 @item @code{debug?} (default: @code{#f})
25563 When true, the daemon performs additional logging for debugging purposes.
25568 @defvr {Scheme Variable} ganeti-wconfd-service-type
25569 @command{ganeti-wconfd} is the daemon that has authoritative knowledge
25570 about the cluster configuration and is the only entity that can accept
25571 changes to it. All jobs that need to modify the configuration will do so
25572 by sending appropriate requests to this daemon. It only runs on the
25573 @dfn{master node} and will automatically disable itself on other nodes.
25575 The value of this service must be a
25576 @code{ganeti-wconfd-configuration} object.
25579 @deftp {Data Type} ganeti-wconfd-configuration
25580 This is the configuration for the @code{ganeti-wconfd} service.
25583 @item @code{ganeti} (default: @code{ganeti})
25584 The @code{ganeti} package to use for this service.
25586 @item @code{no-voting?} (default: @code{#f})
25587 The daemon will refuse to start if the majority of cluster nodes does not
25588 agree that it is running on the master node. Set to @code{#t} to start
25589 even if a quorum can not be reached (dangerous, use with caution).
25591 @item @code{debug?} (default: @code{#f})
25592 When true, the daemon performs additional logging for debugging purposes.
25597 @defvr {Scheme Variable} ganeti-luxid-service-type
25598 @command{ganeti-luxid} is a daemon used to answer queries related to the
25599 configuration and the current live state of a Ganeti cluster. Additionally,
25600 it is the authorative daemon for the Ganeti job queue. Jobs can be
25601 submitted via this daemon and it schedules and starts them.
25603 It takes a @code{ganeti-luxid-configuration} object.
25606 @deftp {Data Type} ganeti-luxid-configuration
25607 This is the configuration for the @code{ganeti-wconfd} service.
25610 @item @code{ganeti} (default: @code{ganeti})
25611 The @code{ganeti} package to use for this service.
25613 @item @code{no-voting?} (default: @code{#f})
25614 The daemon will refuse to start if it cannot verify that the majority of
25615 cluster nodes believes that it is running on the master node. Set to
25616 @code{#t} to ignore such checks and start anyway (this can be dangerous).
25618 @item @code{debug?} (default: @code{#f})
25619 When true, the daemon performs additional logging for debugging purposes.
25624 @defvr {Scheme Variable} ganeti-rapi-service-type
25625 @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
25626 the master node and can be used to perform cluster actions programmatically
25627 via a JSON-based RPC protocol.
25629 Most query operations are allowed without authentication (unless
25630 @var{require-authentication?} is set), whereas write operations require
25631 explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
25632 the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
25633 API documentation} for more information.
25635 The value of this service must be a @code{ganeti-rapi-configuration} object.
25638 @deftp {Data Type} ganeti-rapi-configuration
25639 This is the configuration for the @code{ganeti-rapi} service.
25642 @item @code{ganeti} (default: @code{ganeti})
25643 The @code{ganeti} package to use for this service.
25645 @item @code{require-authentication?} (default: @code{#f})
25646 Whether to require authentication even for read-only operations.
25648 @item @code{port} (default: @code{5080})
25649 The TCP port on which to listen to API requests.
25651 @item @code{address} (default: @code{"0.0.0.0"})
25652 The network address that the service will bind to. By default it listens
25653 on all configured addresses.
25655 @item @code{interface} (default: @code{#f})
25656 When set, it must specify a specific network interface such as @code{eth0}
25657 that the daemon will bind to.
25659 @item @code{max-clients} (default: @code{20})
25660 The maximum number of simultaneous client requests to handle. Further
25661 connections are allowed, but no responses are sent until enough connections
25664 @item @code{ssl?} (default: @code{#t})
25665 Whether to use SSL/TLS encryption on the RAPI port.
25667 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
25668 This can be used to provide a specific encryption key for TLS communications.
25670 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
25671 This can be used to provide a specific certificate for TLS communications.
25673 @item @code{debug?} (default: @code{#f})
25674 When true, the daemon performs additional logging for debugging purposes.
25675 Note that this will leak encryption details to the log files, use with caution.
25680 @defvr {Scheme Variable} ganeti-kvmd-service-type
25681 @command{ganeti-kvmd} is responsible for determining whether a given KVM
25682 instance was shut down by an administrator or a user. Normally Ganeti will
25683 restart an instance that was not stopped through Ganeti itself. If the
25684 cluster option @code{user_shutdown} is true, this daemon monitors the
25685 @code{QMP} socket provided by QEMU and listens for shutdown events, and
25686 marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
25687 it shuts down gracefully by itself.
25689 It takes a @code{ganeti-kvmd-configuration} object.
25692 @deftp {Data Type} ganeti-kvmd-configuration
25695 @item @code{ganeti} (default: @code{ganeti})
25696 The @code{ganeti} package to use for this service.
25698 @item @code{debug?} (default: @code{#f})
25699 When true, the daemon performs additional logging for debugging purposes.
25704 @defvr {Scheme Variable} ganeti-mond-service-type
25705 @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
25706 functionality. It is responsible for running data collectors and publish the
25707 collected information through a HTTP interface.
25709 It takes a @code{ganeti-mond-configuration} object.
25712 @deftp {Data Type} ganeti-mond-configuration
25715 @item @code{ganeti} (default: @code{ganeti})
25716 The @code{ganeti} package to use for this service.
25718 @item @code{port} (default: @code{1815})
25719 The port on which the daemon will listen.
25721 @item @code{address} (default: @code{"0.0.0.0"})
25722 The network address that the daemon will bind to. By default it binds to all
25723 available interfaces.
25725 @item @code{debug?} (default: @code{#f})
25726 When true, the daemon performs additional logging for debugging purposes.
25731 @defvr {Scheme Variable} ganeti-metad-service-type
25732 @command{ganeti-metad} is an optional daemon that can be used to provide
25733 information about the cluster to instances or OS install scripts.
25735 It takes a @code{ganeti-metad-configuration} object.
25738 @deftp {Data Type} ganeti-metad-configuration
25741 @item @code{ganeti} (default: @code{ganeti})
25742 The @code{ganeti} package to use for this service.
25744 @item @code{port} (default: @code{80})
25745 The port on which the daemon will listen.
25747 @item @code{address} (default: @code{#f})
25748 If set, the daemon will bind to this address only. If left unset, the behavior
25749 depends on the cluster configuration.
25751 @item @code{debug?} (default: @code{#f})
25752 When true, the daemon performs additional logging for debugging purposes.
25757 @defvr {Scheme Variable} ganeti-watcher-service-type
25758 @command{ganeti-watcher} is a script designed to run periodically and ensure
25759 the health of a cluster. It will automatically restart instances that have
25760 stopped without Ganetis consent, and repairs DRBD links in case a node has
25761 rebooted. It also archives old cluster jobs and restarts Ganeti daemons
25762 that are not running. If the cluster parameter @code{ensure_node_health}
25763 is set, the watcher will also shutdown instances and DRBD devices if the
25764 node it is running on is declared offline by known master candidates.
25766 It can be paused on all nodes with @command{gnt-cluster watcher pause}.
25768 The service takes a @code{ganeti-watcher-configuration} object.
25771 @deftp {Data Type} ganeti-watcher-configuration
25774 @item @code{ganeti} (default: @code{ganeti})
25775 The @code{ganeti} package to use for this service.
25777 @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
25778 How often to run the script. The default is every five minutes.
25780 @item @code{rapi-ip} (default: @code{#f})
25781 This option needs to be specified only if the RAPI daemon is configured to use
25782 a particular interface or address. By default the cluster address is used.
25784 @item @code{job-age} (default: @code{(* 6 3600)})
25785 Archive cluster jobs older than this age, specified in seconds. The default
25786 is 6 hours. This keeps @command{gnt-job list} manageable.
25788 @item @code{verify-disks?} (default: @code{#t})
25789 If this is @code{#f}, the watcher will not try to repair broken DRBD links
25790 automatically. Administrators will need to use @command{gnt-cluster verify-disks}
25793 @item @code{debug?} (default: @code{#f})
25794 When @code{#t}, the script performs additional logging for debugging purposes.
25799 @defvr {Scheme Variable} ganeti-cleaner-service-type
25800 @command{ganeti-cleaner} is a script designed to run periodically and remove
25801 old files from the cluster. This service type controls two @dfn{cron jobs}:
25802 one intended for the master node that permanently purges old cluster jobs,
25803 and one intended for every node that removes expired X509 certificates, keys,
25804 and outdated @command{ganeti-watcher} information. Like all Ganeti services,
25805 it is safe to include even on non-master nodes as it will disable itself as
25808 It takes a @code{ganeti-cleaner-configuration} object.
25811 @deftp {Data Type} ganeti-cleaner-configuration
25814 @item @code{ganeti} (default: @code{ganeti})
25815 The @code{ganeti} package to use for the @command{gnt-cleaner} command.
25817 @item @code{master-schedule} (default: @code{"45 1 * * *"})
25818 How often to run the master cleaning job. The default is once per day, at
25821 @item @code{node-schedule} (default: @code{"45 2 * * *"})
25822 How often to run the node cleaning job. The default is once per day, at
25828 @node Version Control Services
25829 @subsection Version Control Services
25831 The @code{(gnu services version-control)} module provides a service to
25832 allow remote access to local Git repositories. There are three options:
25833 the @code{git-daemon-service}, which provides access to repositories via
25834 the @code{git://} unsecured TCP-based protocol, extending the
25835 @code{nginx} web server to proxy some requests to
25836 @code{git-http-backend}, or providing a web interface with
25837 @code{cgit-service-type}.
25839 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
25841 Return a service that runs @command{git daemon}, a simple TCP server to
25842 expose repositories over the Git protocol for anonymous access.
25844 The optional @var{config} argument should be a
25845 @code{<git-daemon-configuration>} object, by default it allows read-only
25846 access to exported@footnote{By creating the magic file
25847 @file{git-daemon-export-ok} in the repository directory.} repositories under
25852 @deftp {Data Type} git-daemon-configuration
25853 Data type representing the configuration for @code{git-daemon-service}.
25856 @item @code{package} (default: @code{git})
25857 Package object of the Git distributed version control system.
25859 @item @code{export-all?} (default: @code{#f})
25860 Whether to allow access for all Git repositories, even if they do not
25861 have the @file{git-daemon-export-ok} file.
25863 @item @code{base-path} (default: @file{/srv/git})
25864 Whether to remap all the path requests as relative to the given path.
25865 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
25866 @samp{example.com}, then if you later try to pull
25867 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
25868 path as @file{/srv/git/hello.git}.
25870 @item @code{user-path} (default: @code{#f})
25871 Whether to allow @code{~user} notation to be used in requests. When
25872 specified with empty string, requests to
25873 @indicateurl{git://host/~alice/foo} is taken as a request to access
25874 @code{foo} repository in the home directory of user @code{alice}. If
25875 @code{(user-path "@var{path}")} is specified, the same request is taken
25876 as a request to access @file{@var{path}/foo} repository in the home
25877 directory of user @code{alice}.
25879 @item @code{listen} (default: @code{'()})
25880 Whether to listen on specific IP addresses or hostnames, defaults to
25883 @item @code{port} (default: @code{#f})
25884 Whether to listen on an alternative port, which defaults to 9418.
25886 @item @code{whitelist} (default: @code{'()})
25887 If not empty, only allow access to this list of directories.
25889 @item @code{extra-options} (default: @code{'()})
25890 Extra options will be passed to @command{git daemon}, please run
25891 @command{man git-daemon} for more information.
25896 The @code{git://} protocol lacks authentication. When you pull from a
25897 repository fetched via @code{git://}, you don't know whether the data you
25898 receive was modified or is even coming from the specified host, and your
25899 connection is subject to eavesdropping. It's better to use an authenticated
25900 and encrypted transport, such as @code{https}. Although Git allows you
25901 to serve repositories using unsophisticated file-based web servers,
25902 there is a faster protocol implemented by the @code{git-http-backend}
25903 program. This program is the back-end of a proper Git web service. It
25904 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
25905 on running the necessary @code{fcgiwrap} daemon.
25907 Guix has a separate configuration data type for serving Git repositories
25910 @deftp {Data Type} git-http-configuration
25911 Data type representing the configuration for a future
25912 @code{git-http-service-type}; can currently be used to configure Nginx
25913 trough @code{git-http-nginx-location-configuration}.
25916 @item @code{package} (default: @var{git})
25917 Package object of the Git distributed version control system.
25919 @item @code{git-root} (default: @file{/srv/git})
25920 Directory containing the Git repositories to expose to the world.
25922 @item @code{export-all?} (default: @code{#f})
25923 Whether to expose access for all Git repositories in @var{git-root},
25924 even if they do not have the @file{git-daemon-export-ok} file.
25926 @item @code{uri-path} (default: @samp{/git/})
25927 Path prefix for Git access. With the default @samp{/git/} prefix, this
25928 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
25929 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
25930 with this prefix are not passed on to this Git instance.
25932 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
25933 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
25938 There is no @code{git-http-service-type}, currently; instead you can
25939 create an @code{nginx-location-configuration} from a
25940 @code{git-http-configuration} and then add that location to a web
25943 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
25944 [config=(git-http-configuration)]
25945 Compute an @code{nginx-location-configuration} that corresponds to the
25946 given Git http configuration. An example nginx service definition to
25947 serve the default @file{/srv/git} over HTTPS might be:
25950 (service nginx-service-type
25951 (nginx-configuration
25954 (nginx-server-configuration
25955 (listen '("443 ssl"))
25956 (server-name "git.my-host.org")
25958 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
25959 (ssl-certificate-key
25960 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
25963 (git-http-nginx-location-configuration
25964 (git-http-configuration (uri-path "/"))))))))))
25967 This example assumes that you are using Let's Encrypt to get your TLS
25968 certificate. @xref{Certificate Services}. The default @code{certbot}
25969 service will redirect all HTTP traffic on @code{git.my-host.org} to
25970 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
25971 system services. @xref{Web Services}.
25974 @subsubheading Cgit Service
25976 @cindex Cgit service
25977 @cindex Git, web interface
25978 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
25979 repositories written in C.
25981 The following example will configure the service with default values.
25982 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
25985 (service cgit-service-type)
25988 The @code{file-object} type designates either a file-like object
25989 (@pxref{G-Expressions, file-like objects}) or a string.
25991 @c %start of fragment
25993 Available @code{cgit-configuration} fields are:
25995 @deftypevr {@code{cgit-configuration} parameter} package package
26000 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
26001 NGINX configuration.
26005 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
26006 Specifies a command which will be invoked to format the content of about
26007 pages (both top-level and for each repository).
26009 Defaults to @samp{""}.
26013 @deftypevr {@code{cgit-configuration} parameter} string agefile
26014 Specifies a path, relative to each repository path, which can be used to
26015 specify the date and time of the youngest commit in the repository.
26017 Defaults to @samp{""}.
26021 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
26022 Specifies a command that will be invoked for authenticating repository
26025 Defaults to @samp{""}.
26029 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
26030 Flag which, when set to @samp{age}, enables date ordering in the branch
26031 ref list, and when set @samp{name} enables ordering by branch name.
26033 Defaults to @samp{"name"}.
26037 @deftypevr {@code{cgit-configuration} parameter} string cache-root
26038 Path used to store the cgit cache entries.
26040 Defaults to @samp{"/var/cache/cgit"}.
26044 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
26045 Number which specifies the time-to-live, in minutes, for the cached
26046 version of repository pages accessed with a fixed SHA1.
26048 Defaults to @samp{-1}.
26052 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
26053 Number which specifies the time-to-live, in minutes, for the cached
26054 version of repository pages accessed without a fixed SHA1.
26056 Defaults to @samp{5}.
26060 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
26061 Number which specifies the time-to-live, in minutes, for the cached
26062 version of the repository summary page.
26064 Defaults to @samp{5}.
26068 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
26069 Number which specifies the time-to-live, in minutes, for the cached
26070 version of the repository index page.
26072 Defaults to @samp{5}.
26076 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
26077 Number which specifies the time-to-live, in minutes, for the result of
26078 scanning a path for Git repositories.
26080 Defaults to @samp{15}.
26084 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
26085 Number which specifies the time-to-live, in minutes, for the cached
26086 version of the repository about page.
26088 Defaults to @samp{15}.
26092 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
26093 Number which specifies the time-to-live, in minutes, for the cached
26094 version of snapshots.
26096 Defaults to @samp{5}.
26100 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
26101 The maximum number of entries in the cgit cache. When set to @samp{0},
26102 caching is disabled.
26104 Defaults to @samp{0}.
26108 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
26109 Sort items in the repo list case sensitively.
26111 Defaults to @samp{#t}.
26115 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
26116 List of common prefixes which, when combined with a repository URL,
26117 generates valid clone URLs for the repository.
26119 Defaults to @samp{()}.
26123 @deftypevr {@code{cgit-configuration} parameter} list clone-url
26124 List of @code{clone-url} templates.
26126 Defaults to @samp{()}.
26130 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
26131 Command which will be invoked to format commit messages.
26133 Defaults to @samp{""}.
26137 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
26138 Flag which, when set to @samp{date}, enables strict date ordering in the
26139 commit log, and when set to @samp{topo} enables strict topological
26142 Defaults to @samp{"git log"}.
26146 @deftypevr {@code{cgit-configuration} parameter} file-object css
26147 URL which specifies the css document to include in all cgit pages.
26149 Defaults to @samp{"/share/cgit/cgit.css"}.
26153 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
26154 Specifies a command which will be invoked to format names and email
26155 address of committers, authors, and taggers, as represented in various
26156 places throughout the cgit interface.
26158 Defaults to @samp{""}.
26162 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
26163 Flag which, when set to @samp{#t}, will make cgit generate a HTML
26164 fragment suitable for embedding in other HTML pages.
26166 Defaults to @samp{#f}.
26170 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
26171 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
26172 commit history graph to the left of the commit messages in the
26173 repository log page.
26175 Defaults to @samp{#f}.
26179 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
26180 Flag which, when set to @samp{#t}, allows all filter settings to be
26181 overridden in repository-specific cgitrc files.
26183 Defaults to @samp{#f}.
26187 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
26188 Flag which, when set to @samp{#t}, allows users to follow a file in the
26191 Defaults to @samp{#f}.
26195 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
26196 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
26199 Defaults to @samp{#t}.
26203 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
26204 Flag which, when set to @samp{#t}, will make cgit generate extra links
26205 "summary", "commit", "tree" for each repo in the repository index.
26207 Defaults to @samp{#f}.
26211 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
26212 Flag which, when set to @samp{#t}, will make cgit display the owner of
26213 each repo in the repository index.
26215 Defaults to @samp{#t}.
26219 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
26220 Flag which, when set to @samp{#t}, will make cgit print the number of
26221 modified files for each commit on the repository log page.
26223 Defaults to @samp{#f}.
26227 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
26228 Flag which, when set to @samp{#t}, will make cgit print the number of
26229 added and removed lines for each commit on the repository log page.
26231 Defaults to @samp{#f}.
26235 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
26236 Flag which, when set to @code{#t}, will make cgit display remote
26237 branches in the summary and refs views.
26239 Defaults to @samp{#f}.
26243 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
26244 Flag which, when set to @code{1}, will make cgit use the subject of the
26245 parent commit as link text when generating links to parent commits in
26248 Defaults to @samp{#f}.
26252 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
26253 Flag which, when set to @samp{#t}, will make cgit use the subject of the
26254 parent commit as link text when generating links to parent commits in
26257 Defaults to @samp{#f}.
26261 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
26262 Flag which, when set to @samp{#t}, will make cgit generate linenumber
26263 links for plaintext blobs printed in the tree view.
26265 Defaults to @samp{#t}.
26269 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
26270 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
26271 set any repo specific settings.
26273 Defaults to @samp{#f}.
26277 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
26278 URL used as link to a shortcut icon for cgit.
26280 Defaults to @samp{"/favicon.ico"}.
26284 @deftypevr {@code{cgit-configuration} parameter} string footer
26285 The content of the file specified with this option will be included
26286 verbatim at the bottom of all pages (i.e.@: it replaces the standard
26287 "generated by..."@: message).
26289 Defaults to @samp{""}.
26293 @deftypevr {@code{cgit-configuration} parameter} string head-include
26294 The content of the file specified with this option will be included
26295 verbatim in the HTML HEAD section on all pages.
26297 Defaults to @samp{""}.
26301 @deftypevr {@code{cgit-configuration} parameter} string header
26302 The content of the file specified with this option will be included
26303 verbatim at the top of all pages.
26305 Defaults to @samp{""}.
26309 @deftypevr {@code{cgit-configuration} parameter} file-object include
26310 Name of a configfile to include before the rest of the current config-
26313 Defaults to @samp{""}.
26317 @deftypevr {@code{cgit-configuration} parameter} string index-header
26318 The content of the file specified with this option will be included
26319 verbatim above the repository index.
26321 Defaults to @samp{""}.
26325 @deftypevr {@code{cgit-configuration} parameter} string index-info
26326 The content of the file specified with this option will be included
26327 verbatim below the heading on the repository index page.
26329 Defaults to @samp{""}.
26333 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
26334 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
26335 in the servers timezone.
26337 Defaults to @samp{#f}.
26341 @deftypevr {@code{cgit-configuration} parameter} file-object logo
26342 URL which specifies the source of an image which will be used as a logo
26345 Defaults to @samp{"/share/cgit/cgit.png"}.
26349 @deftypevr {@code{cgit-configuration} parameter} string logo-link
26350 URL loaded when clicking on the cgit logo image.
26352 Defaults to @samp{""}.
26356 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
26357 Command which will be invoked to format the Owner column of the main
26360 Defaults to @samp{""}.
26364 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
26365 Number of items to display in atom feeds view.
26367 Defaults to @samp{10}.
26371 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
26372 Number of entries to list per page in "log" view.
26374 Defaults to @samp{50}.
26378 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
26379 Number of commit message characters to display in "log" view.
26381 Defaults to @samp{80}.
26385 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
26386 Specifies the number of entries to list per page on the repository index
26389 Defaults to @samp{50}.
26393 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
26394 Specifies the maximum number of repo description characters to display
26395 on the repository index page.
26397 Defaults to @samp{80}.
26401 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
26402 Specifies the maximum size of a blob to display HTML for in KBytes.
26404 Defaults to @samp{0}.
26408 @deftypevr {@code{cgit-configuration} parameter} string max-stats
26409 Maximum statistics period. Valid values are @samp{week},@samp{month},
26410 @samp{quarter} and @samp{year}.
26412 Defaults to @samp{""}.
26416 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
26417 Mimetype for the specified filename extension.
26419 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
26420 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
26421 "image/png") (svg "image/svg+xml"))}.
26425 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
26426 Specifies the file to use for automatic mimetype lookup.
26428 Defaults to @samp{""}.
26432 @deftypevr {@code{cgit-configuration} parameter} string module-link
26433 Text which will be used as the formatstring for a hyperlink when a
26434 submodule is printed in a directory listing.
26436 Defaults to @samp{""}.
26440 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
26441 If set to the value @samp{#t} caching will be disabled.
26443 Defaults to @samp{#f}.
26447 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
26448 If set to @samp{#t} showing full author email addresses will be
26451 Defaults to @samp{#f}.
26455 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
26456 Flag which, when set to @samp{#t}, will make cgit omit the standard
26457 header on all pages.
26459 Defaults to @samp{#f}.
26463 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
26464 A list of subdirectories inside of @code{repository-directory}, relative
26465 to it, that should loaded as Git repositories. An empty list means that
26466 all subdirectories will be loaded.
26468 Defaults to @samp{()}.
26472 @deftypevr {@code{cgit-configuration} parameter} file-object readme
26473 Text which will be used as default value for @code{cgit-repo-readme}.
26475 Defaults to @samp{""}.
26479 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
26480 If set to @code{#t} and @code{repository-directory} is enabled, if any
26481 repositories are found with a suffix of @code{.git}, this suffix will be
26482 removed for the URL and name.
26484 Defaults to @samp{#f}.
26488 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
26489 Maximum number of files to consider when detecting renames.
26491 Defaults to @samp{-1}.
26495 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
26496 The way in which repositories in each section are sorted.
26498 Defaults to @samp{""}.
26502 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
26503 Text used as content for the @code{robots} meta-tag.
26505 Defaults to @samp{("noindex" "nofollow")}.
26509 @deftypevr {@code{cgit-configuration} parameter} string root-desc
26510 Text printed below the heading on the repository index page.
26512 Defaults to @samp{"a fast webinterface for the git dscm"}.
26516 @deftypevr {@code{cgit-configuration} parameter} string root-readme
26517 The content of the file specified with this option will be included
26518 verbatim below the ``about'' link on the repository index page.
26520 Defaults to @samp{""}.
26524 @deftypevr {@code{cgit-configuration} parameter} string root-title
26525 Text printed as heading on the repository index page.
26527 Defaults to @samp{""}.
26531 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
26532 If set to @samp{#t} and repository-directory is enabled,
26533 repository-directory will recurse into directories whose name starts
26534 with a period. Otherwise, repository-directory will stay away from such
26535 directories, considered as ``hidden''. Note that this does not apply to
26536 the @file{.git} directory in non-bare repos.
26538 Defaults to @samp{#f}.
26542 @deftypevr {@code{cgit-configuration} parameter} list snapshots
26543 Text which specifies the default set of snapshot formats that cgit
26544 generates links for.
26546 Defaults to @samp{()}.
26550 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
26551 Name of the directory to scan for repositories (represents
26554 Defaults to @samp{"/srv/git"}.
26558 @deftypevr {@code{cgit-configuration} parameter} string section
26559 The name of the current repository section - all repositories defined
26560 after this option will inherit the current section name.
26562 Defaults to @samp{""}.
26566 @deftypevr {@code{cgit-configuration} parameter} string section-sort
26567 Flag which, when set to @samp{1}, will sort the sections on the
26568 repository listing by name.
26570 Defaults to @samp{""}.
26574 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
26575 A number which, if defined prior to repository-directory, specifies how
26576 many path elements from each repo path to use as a default section name.
26578 Defaults to @samp{0}.
26582 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
26583 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
26586 Defaults to @samp{#f}.
26590 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
26591 Specifies a command which will be invoked to format plaintext blobs in
26594 Defaults to @samp{""}.
26598 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
26599 Specifies the number of branches to display in the repository ``summary''
26602 Defaults to @samp{10}.
26606 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
26607 Specifies the number of log entries to display in the repository
26610 Defaults to @samp{10}.
26614 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
26615 Specifies the number of tags to display in the repository ``summary''
26618 Defaults to @samp{10}.
26622 @deftypevr {@code{cgit-configuration} parameter} string strict-export
26623 Filename which, if specified, needs to be present within the repository
26624 for cgit to allow access to that repository.
26626 Defaults to @samp{""}.
26630 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
26631 URL which, if specified, will be used as root for all cgit links.
26633 Defaults to @samp{"/"}.
26637 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
26638 A list of @dfn{cgit-repo} records to use with config.
26640 Defaults to @samp{()}.
26642 Available @code{repository-cgit-configuration} fields are:
26644 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
26645 A mask of snapshot formats for this repo that cgit generates links for,
26646 restricted by the global @code{snapshots} setting.
26648 Defaults to @samp{()}.
26652 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
26653 Override the default @code{source-filter}.
26655 Defaults to @samp{""}.
26659 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
26660 The relative URL used to access the repository.
26662 Defaults to @samp{""}.
26666 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
26667 Override the default @code{about-filter}.
26669 Defaults to @samp{""}.
26673 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
26674 Flag which, when set to @samp{age}, enables date ordering in the branch
26675 ref list, and when set to @samp{name} enables ordering by branch name.
26677 Defaults to @samp{""}.
26681 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
26682 A list of URLs which can be used to clone repo.
26684 Defaults to @samp{()}.
26688 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
26689 Override the default @code{commit-filter}.
26691 Defaults to @samp{""}.
26695 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
26696 Flag which, when set to @samp{date}, enables strict date ordering in the
26697 commit log, and when set to @samp{topo} enables strict topological
26700 Defaults to @samp{""}.
26704 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
26705 The name of the default branch for this repository. If no such branch
26706 exists in the repository, the first branch name (when sorted) is used as
26707 default instead. By default branch pointed to by HEAD, or ``master'' if
26708 there is no suitable HEAD.
26710 Defaults to @samp{""}.
26714 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
26715 The value to show as repository description.
26717 Defaults to @samp{""}.
26721 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
26722 The value to show as repository homepage.
26724 Defaults to @samp{""}.
26728 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
26729 Override the default @code{email-filter}.
26731 Defaults to @samp{""}.
26735 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
26736 A flag which can be used to disable the global setting
26737 @code{enable-commit-graph?}.
26739 Defaults to @samp{disabled}.
26743 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
26744 A flag which can be used to disable the global setting
26745 @code{enable-log-filecount?}.
26747 Defaults to @samp{disabled}.
26751 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
26752 A flag which can be used to disable the global setting
26753 @code{enable-log-linecount?}.
26755 Defaults to @samp{disabled}.
26759 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
26760 Flag which, when set to @code{#t}, will make cgit display remote
26761 branches in the summary and refs views.
26763 Defaults to @samp{disabled}.
26767 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
26768 A flag which can be used to override the global setting
26769 @code{enable-subject-links?}.
26771 Defaults to @samp{disabled}.
26775 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
26776 A flag which can be used to override the global setting
26777 @code{enable-html-serving?}.
26779 Defaults to @samp{disabled}.
26783 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
26784 Flag which, when set to @code{#t}, hides the repository from the
26787 Defaults to @samp{#f}.
26791 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
26792 Flag which, when set to @samp{#t}, ignores the repository.
26794 Defaults to @samp{#f}.
26798 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
26799 URL which specifies the source of an image which will be used as a logo
26800 on this repo’s pages.
26802 Defaults to @samp{""}.
26806 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
26807 URL loaded when clicking on the cgit logo image.
26809 Defaults to @samp{""}.
26813 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
26814 Override the default @code{owner-filter}.
26816 Defaults to @samp{""}.
26820 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
26821 Text which will be used as the formatstring for a hyperlink when a
26822 submodule is printed in a directory listing. The arguments for the
26823 formatstring are the path and SHA1 of the submodule commit.
26825 Defaults to @samp{""}.
26829 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
26830 Text which will be used as the formatstring for a hyperlink when a
26831 submodule with the specified subdirectory path is printed in a directory
26834 Defaults to @samp{()}.
26838 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
26839 Override the default maximum statistics period.
26841 Defaults to @samp{""}.
26845 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
26846 The value to show as repository name.
26848 Defaults to @samp{""}.
26852 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
26853 A value used to identify the owner of the repository.
26855 Defaults to @samp{""}.
26859 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
26860 An absolute path to the repository directory.
26862 Defaults to @samp{""}.
26866 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
26867 A path (relative to repo) which specifies a file to include verbatim as
26868 the ``About'' page for this repo.
26870 Defaults to @samp{""}.
26874 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
26875 The name of the current repository section - all repositories defined
26876 after this option will inherit the current section name.
26878 Defaults to @samp{""}.
26882 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
26883 Extra options will be appended to cgitrc file.
26885 Defaults to @samp{()}.
26891 @deftypevr {@code{cgit-configuration} parameter} list extra-options
26892 Extra options will be appended to cgitrc file.
26894 Defaults to @samp{()}.
26899 @c %end of fragment
26901 However, it could be that you just want to get a @code{cgitrc} up and
26902 running. In that case, you can pass an @code{opaque-cgit-configuration}
26903 as a record to @code{cgit-service-type}. As its name indicates, an
26904 opaque configuration does not have easy reflective capabilities.
26906 Available @code{opaque-cgit-configuration} fields are:
26908 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
26912 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
26913 The contents of the @code{cgitrc}, as a string.
26916 For example, if your @code{cgitrc} is just the empty string, you
26917 could instantiate a cgit service like this:
26920 (service cgit-service-type
26921 (opaque-cgit-configuration
26925 @subsubheading Gitolite Service
26927 @cindex Gitolite service
26928 @cindex Git, hosting
26929 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
26930 repositories on a central server.
26932 Gitolite can handle multiple repositories and users, and supports flexible
26933 configuration of the permissions for the users on the repositories.
26935 The following example will configure Gitolite using the default @code{git}
26936 user, and the provided SSH public key.
26939 (service gitolite-service-type
26940 (gitolite-configuration
26941 (admin-pubkey (plain-file
26943 "ssh-rsa AAAA... guix@@example.com"))))
26946 Gitolite is configured through a special admin repository which you can clone,
26947 for example, if you setup Gitolite on @code{example.com}, you would run the
26948 following command to clone the admin repository.
26951 git clone git@@example.com:gitolite-admin
26954 When the Gitolite service is activated, the provided @code{admin-pubkey} will
26955 be inserted in to the @file{keydir} directory in the gitolite-admin
26956 repository. If this results in a change in the repository, it will be
26957 committed using the message ``gitolite setup by GNU Guix''.
26959 @deftp {Data Type} gitolite-configuration
26960 Data type representing the configuration for @code{gitolite-service-type}.
26963 @item @code{package} (default: @var{gitolite})
26964 Gitolite package to use.
26966 @item @code{user} (default: @var{git})
26967 User to use for Gitolite. This will be user that you use when accessing
26970 @item @code{group} (default: @var{git})
26971 Group to use for Gitolite.
26973 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
26974 Directory in which to store the Gitolite configuration and repositories.
26976 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
26977 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
26978 representing the configuration for Gitolite.
26980 @item @code{admin-pubkey} (default: @var{#f})
26981 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
26982 setup Gitolite. This will be inserted in to the @file{keydir} directory
26983 within the gitolite-admin repository.
26985 To specify the SSH key as a string, use the @code{plain-file} function.
26988 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
26994 @deftp {Data Type} gitolite-rc-file
26995 Data type representing the Gitolite RC file.
26998 @item @code{umask} (default: @code{#o0077})
26999 This controls the permissions Gitolite sets on the repositories and their
27002 A value like @code{#o0027} will give read access to the group used by Gitolite
27003 (by default: @code{git}). This is necessary when using Gitolite with software
27004 like cgit or gitweb.
27006 @item @code{git-config-keys} (default: @code{""})
27007 Gitolite allows you to set git config values using the @samp{config} keyword. This
27008 setting allows control over the config keys to accept.
27010 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
27011 Set the role names allowed to be used by users running the perms command.
27013 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
27014 This setting controls the commands and features to enable within Gitolite.
27020 @node Game Services
27021 @subsection Game Services
27023 @subsubheading The Battle for Wesnoth Service
27025 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
27026 based tactical strategy game, with several single player campaigns, and
27027 multiplayer games (both networked and local).
27029 @defvar {Scheme Variable} wesnothd-service-type
27030 Service type for the wesnothd service. Its value must be a
27031 @code{wesnothd-configuration} object. To run wesnothd in the default
27032 configuration, instantiate it as:
27035 (service wesnothd-service-type)
27039 @deftp {Data Type} wesnothd-configuration
27040 Data type representing the configuration of @command{wesnothd}.
27043 @item @code{package} (default: @code{wesnoth-server})
27044 The wesnoth server package to use.
27046 @item @code{port} (default: @code{15000})
27047 The port to bind the server to.
27052 @node PAM Mount Service
27053 @subsection PAM Mount Service
27056 The @code{(gnu services pam-mount)} module provides a service allowing
27057 users to mount volumes when they log in. It should be able to mount any
27058 volume format supported by the system.
27060 @defvar {Scheme Variable} pam-mount-service-type
27061 Service type for PAM Mount support.
27064 @deftp {Data Type} pam-mount-configuration
27065 Data type representing the configuration of PAM Mount.
27067 It takes the following parameters:
27071 The configuration rules that will be used to generate
27072 @file{/etc/security/pam_mount.conf.xml}.
27074 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
27075 Guile Reference Manual}), and the the default ones don't mount anything
27076 for anyone at login:
27079 `((debug (@@ (enable "0")))
27080 (mntoptions (@@ (allow ,(string-join
27081 '("nosuid" "nodev" "loop"
27082 "encryption" "fsck" "nonempty"
27083 "allow_root" "allow_other")
27085 (mntoptions (@@ (require "nosuid,nodev")))
27086 (logout (@@ (wait "0")
27090 (mkmountpoint (@@ (enable "1")
27094 Some @code{volume} elements must be added to automatically mount volumes
27095 at login. Here's an example allowing the user @code{alice} to mount her
27096 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
27097 the partition where he stores his data:
27100 (define pam-mount-rules
27101 `((debug (@@ (enable "0")))
27102 (volume (@@ (user "alice")
27105 (mountpoint "/home/alice")))
27106 (volume (@@ (user "bob")
27109 (mountpoint "/home/bob/data")
27110 (options "defaults,autodefrag,compress")))
27111 (mntoptions (@@ (allow ,(string-join
27112 '("nosuid" "nodev" "loop"
27113 "encryption" "fsck" "nonempty"
27114 "allow_root" "allow_other")
27116 (mntoptions (@@ (require "nosuid,nodev")))
27117 (logout (@@ (wait "0")
27121 (mkmountpoint (@@ (enable "1")
27122 (remove "true")))))
27124 (service pam-mount-service-type
27125 (pam-mount-configuration
27126 (rules pam-mount-rules)))
27129 The complete list of possible options can be found in the man page for
27130 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
27135 @node Guix Services
27136 @subsection Guix Services
27138 @subsubheading Guix Data Service
27139 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
27140 and provides data about GNU Guix. This includes information about
27141 packages, derivations and lint warnings.
27143 The data is stored in a PostgreSQL database, and available through a web
27146 @defvar {Scheme Variable} guix-data-service-type
27147 Service type for the Guix Data Service. Its value must be a
27148 @code{guix-data-service-configuration} object. The service optionally
27149 extends the getmail service, as the guix-commits mailing list is used to
27150 find out about changes in the Guix git repository.
27153 @deftp {Data Type} guix-data-service-configuration
27154 Data type representing the configuration of the Guix Data Service.
27157 @item @code{package} (default: @code{guix-data-service})
27158 The Guix Data Service package to use.
27160 @item @code{user} (default: @code{"guix-data-service"})
27161 The system user to run the service as.
27163 @item @code{group} (default: @code{"guix-data-service"})
27164 The system group to run the service as.
27166 @item @code{port} (default: @code{8765})
27167 The port to bind the web service to.
27169 @item @code{host} (default: @code{"127.0.0.1"})
27170 The host to bind the web service to.
27172 @item @code{getmail-idle-mailboxes} (default: @code{#f})
27173 If set, this is the list of mailboxes that the getmail service will be
27174 configured to listen to.
27176 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
27177 If set, this is the @code{getmail-retriever-configuration} object with
27178 which to configure getmail to fetch mail from the guix-commits mailing
27181 @item @code{extra-options} (default: @var{'()})
27182 Extra command line options for @code{guix-data-service}.
27184 @item @code{extra-process-jobs-options} (default: @var{'()})
27185 Extra command line options for @code{guix-data-service-process-jobs}.
27190 @node Linux Services
27191 @subsection Linux Services
27194 @cindex out of memory killer
27196 @cindex early out of memory daemon
27197 @subsubheading Early OOM Service
27199 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
27200 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
27201 space and provides a more responsive and configurable alternative to the
27202 in-kernel OOM killer. It is useful to prevent the system from becoming
27203 unresponsive when it runs out of memory.
27205 @deffn {Scheme Variable} earlyoom-service-type
27206 The service type for running @command{earlyoom}, the Early OOM daemon.
27207 Its value must be a @code{earlyoom-configuration} object, described
27208 below. The service can be instantiated in its default configuration
27212 (service earlyoom-service-type)
27216 @deftp {Data Type} earlyoom-configuration
27217 This is the configuration record for the @code{earlyoom-service-type}.
27220 @item @code{earlyoom} (default: @var{earlyoom})
27221 The Earlyoom package to use.
27223 @item @code{minimum-available-memory} (default: @code{10})
27224 The threshold for the minimum @emph{available} memory, in percentages.
27226 @item @code{minimum-free-swap} (default: @code{10})
27227 The threshold for the minimum free swap memory, in percentages.
27229 @item @code{prefer-regexp} (default: @code{#f})
27230 A regular expression (as a string) to match the names of the processes
27231 that should be preferably killed.
27233 @item @code{avoid-regexp} (default: @code{#f})
27234 A regular expression (as a string) to match the names of the processes
27235 that should @emph{not} be killed.
27237 @item @code{memory-report-interval} (default: @code{0})
27238 The interval in seconds at which a memory report is printed. It is
27239 disabled by default.
27241 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
27242 A boolean indicating whether the positive adjustments set in
27243 @file{/proc/*/oom_score_adj}.
27245 @item @code{show-debug-messages?} (default: @code{#f})
27246 A boolean indicating whether debug messages should be printed. The logs
27247 are saved at @file{/var/log/earlyoom.log}.
27249 @item @code{send-notification-command} (default: @code{#f})
27250 This can be used to provide a custom command used for sending
27256 @cindex kernel module loader
27257 @subsubheading Kernel Module Loader Service
27259 The kernel module loader service allows one to load loadable kernel
27260 modules at boot. This is especially useful for modules that don't
27261 autoload and need to be manually loaded, as it's the case with
27264 @deffn {Scheme Variable} kernel-module-loader-service-type
27265 The service type for loading loadable kernel modules at boot with
27266 @command{modprobe}. Its value must be a list of strings representing
27267 module names. For example loading the drivers provided by
27268 @code{ddcci-driver-linux}, in debugging mode by passing some module
27269 parameters, can be done as follow:
27272 (use-modules (gnu) (gnu services))
27273 (use-package-modules linux)
27274 (use-service-modules linux)
27276 (define ddcci-config
27277 (plain-file "ddcci.conf"
27278 "options ddcci dyndbg delay=120"))
27282 (services (cons* (service kernel-module-loader-service-type
27283 '("ddcci" "ddcci_backlight"))
27284 (simple-service 'ddcci-config etc-service-type
27285 (list `("modprobe.d/ddcci.conf"
27288 (kernel-loadable-modules (list ddcci-driver-linux)))
27293 @cindex compressed swap
27294 @cindex Compressed RAM-based block devices
27295 @subsubheading Zram Device Service
27297 The Zram device service provides a compressed swap device in system
27298 memory. The Linux Kernel documentation has more information about
27299 @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
27302 @deffn {Scheme Variable} zram-device-service-type
27303 This service creates the zram block device, formats it as swap and
27304 enables it as a swap device. The service's value is a
27305 @code{zram-device-configuration} record.
27307 @deftp {Data Type} zram-device-configuration
27308 This is the data type representing the configuration for the zram-device
27312 @item @code{size} (default @var{"1G"})
27313 This is the amount of space you wish to provide for the zram device. It
27314 accepts a string and can be a number of bytes or use a suffix, eg.:
27315 @var{"512M"} or @var{1024000}.
27316 @item @code{compression-algorithm} (default @var{'lzo})
27317 This is the compression algorithm you wish to use. It is difficult to
27318 list all the possible compression options, but common ones supported by
27319 Guix's Linux Libre Kernel include @var{'lzo}, @var{'lz4} and @var{'zstd}.
27320 @item @code{memory-limit} (default @var{0})
27321 This is the maximum amount of memory which the zram device can use.
27322 Setting it to '0' disables the limit. While it is generally expected
27323 that compression will be 2:1, it is possible that uncompressable data
27324 can be written to swap and this is a method to limit how much memory can
27325 be used. It accepts a string and can be a number of bytes or use a
27326 suffix, eg.: @var{"2G"}.
27327 @item @code{priority} (default @var{-1})
27328 This is the priority of the swap device created from the zram device.
27329 @code{swapon} accepts values between -1 and 32767, with higher values
27330 indicating higher priority. Higher priority swap will generally be used
27337 @node Hurd Services
27338 @subsection Hurd Services
27340 @defvr {Scheme Variable} hurd-console-service-type
27341 This service starts the fancy @code{VGA} console client on the Hurd.
27343 The service's value is a @code{hurd-console-configuration} record.
27346 @deftp {Data Type} hurd-console-configuration
27347 This is the data type representing the configuration for the
27348 hurd-console-service.
27351 @item @code{hurd} (default: @var{hurd})
27352 The Hurd package to use.
27356 @defvr {Scheme Variable} hurd-getty-service-type
27357 This service starts a tty using the Hurd @code{getty} program.
27359 The service's value is a @code{hurd-getty-configuration} record.
27362 @deftp {Data Type} hurd-getty-configuration
27363 This is the data type representing the configuration for the
27364 hurd-getty-service.
27367 @item @code{hurd} (default: @var{hurd})
27368 The Hurd package to use.
27371 The name of the console this Getty runs on---e.g., @code{"tty1"}.
27373 @item @code{baud-rate} (default: @code{38400})
27374 An integer specifying the baud rate of the tty.
27379 @node Miscellaneous Services
27380 @subsection Miscellaneous Services
27382 @cindex fingerprint
27383 @subsubheading Fingerprint Service
27385 The @code{(gnu services authentication)} module provides a DBus service to
27386 read and identify fingerprints via a fingerprint sensor.
27388 @defvr {Scheme Variable} fprintd-service-type
27389 The service type for @command{fprintd}, which provides the fingerprint
27390 reading capability.
27393 (service fprintd-service-type)
27398 @subsubheading System Control Service
27400 The @code{(gnu services sysctl)} provides a service to configure kernel
27401 parameters at boot.
27403 @defvr {Scheme Variable} sysctl-service-type
27404 The service type for @command{sysctl}, which modifies kernel parameters
27405 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
27409 (service sysctl-service-type
27410 (sysctl-configuration
27411 (settings '(("net.ipv4.ip_forward" . "1")))))
27415 @deftp {Data Type} sysctl-configuration
27416 The data type representing the configuration of @command{sysctl}.
27419 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
27420 The @command{sysctl} executable to use.
27422 @item @code{settings} (default: @code{'()})
27423 An association list specifies kernel parameters and their values.
27428 @subsubheading PC/SC Smart Card Daemon Service
27430 The @code{(gnu services security-token)} module provides the following service
27431 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
27432 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
27433 manager that coordinates communications with smart card readers, smart cards
27434 and cryptographic tokens that are connected to the system.
27436 @defvr {Scheme Variable} pcscd-service-type
27437 Service type for the @command{pcscd} service. Its value must be a
27438 @code{pcscd-configuration} object. To run pcscd in the default
27439 configuration, instantiate it as:
27442 (service pcscd-service-type)
27446 @deftp {Data Type} pcscd-configuration
27447 The data type representing the configuration of @command{pcscd}.
27450 @item @code{pcsc-lite} (default: @code{pcsc-lite})
27451 The pcsc-lite package that provides pcscd.
27452 @item @code{usb-drivers} (default: @code{(list ccid)})
27453 List of packages that provide USB drivers to pcscd. Drivers are expected to be
27454 under @file{pcsc/drivers} in the store directory of the package.
27459 @subsubheading Lirc Service
27461 The @code{(gnu services lirc)} module provides the following service.
27463 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
27464 [#:device #f] [#:driver #f] [#:config-file #f] @
27465 [#:extra-options '()]
27466 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
27467 decodes infrared signals from remote controls.
27469 Optionally, @var{device}, @var{driver} and @var{config-file}
27470 (configuration file name) may be specified. See @command{lircd} manual
27473 Finally, @var{extra-options} is a list of additional command-line options
27474 passed to @command{lircd}.
27478 @subsubheading Spice Service
27480 The @code{(gnu services spice)} module provides the following service.
27482 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
27483 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
27484 that enables sharing the clipboard with a vm and setting the guest display
27485 resolution when the graphical console window resizes.
27488 @cindex inputattach
27489 @subsubheading inputattach Service
27491 @cindex tablet input, for Xorg
27492 @cindex touchscreen input, for Xorg
27493 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
27494 use input devices such as Wacom tablets, touchscreens, or joysticks with the
27495 Xorg display server.
27497 @deffn {Scheme Variable} inputattach-service-type
27498 Type of a service that runs @command{inputattach} on a device and
27499 dispatches events from it.
27502 @deftp {Data Type} inputattach-configuration
27504 @item @code{device-type} (default: @code{"wacom"})
27505 The type of device to connect to. Run @command{inputattach --help}, from the
27506 @code{inputattach} package, to see the list of supported device types.
27508 @item @code{device} (default: @code{"/dev/ttyS0"})
27509 The device file to connect to the device.
27511 @item @code{baud-rate} (default: @code{#f})
27512 Baud rate to use for the serial connection.
27513 Should be a number or @code{#f}.
27515 @item @code{log-file} (default: @code{#f})
27516 If true, this must be the name of a file to log messages to.
27520 @subsubheading Dictionary Service
27522 The @code{(gnu services dict)} module provides the following service:
27524 @defvr {Scheme Variable} dicod-service-type
27525 This is the type of the service that runs the @command{dicod} daemon, an
27526 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
27529 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
27530 Return a service that runs the @command{dicod} daemon, an implementation
27531 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
27533 The optional @var{config} argument specifies the configuration for
27534 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
27535 default it serves the GNU Collaborative International Dictionary of English.
27537 You can add @command{open localhost} to your @file{~/.dico} file to make
27538 @code{localhost} the default server for @command{dico} client
27539 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
27542 @deftp {Data Type} dicod-configuration
27543 Data type representing the configuration of dicod.
27546 @item @code{dico} (default: @var{dico})
27547 Package object of the GNU Dico dictionary server.
27549 @item @code{interfaces} (default: @var{'("localhost")})
27550 This is the list of IP addresses and ports and possibly socket file
27551 names to listen to (@pxref{Server Settings, @code{listen} directive,,
27552 dico, GNU Dico Manual}).
27554 @item @code{handlers} (default: @var{'()})
27555 List of @code{<dicod-handler>} objects denoting handlers (module instances).
27557 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
27558 List of @code{<dicod-database>} objects denoting dictionaries to be served.
27562 @deftp {Data Type} dicod-handler
27563 Data type representing a dictionary handler (module instance).
27567 Name of the handler (module instance).
27569 @item @code{module} (default: @var{#f})
27570 Name of the dicod module of the handler (instance). If it is @code{#f},
27571 the module has the same name as the handler.
27572 (@pxref{Modules,,, dico, GNU Dico Manual}).
27574 @item @code{options}
27575 List of strings or gexps representing the arguments for the module handler
27579 @deftp {Data Type} dicod-database
27580 Data type representing a dictionary database.
27584 Name of the database, will be used in DICT commands.
27586 @item @code{handler}
27587 Name of the dicod handler (module instance) used by this database
27588 (@pxref{Handlers,,, dico, GNU Dico Manual}).
27590 @item @code{complex?} (default: @var{#f})
27591 Whether the database configuration complex. The complex configuration
27592 will need a corresponding @code{<dicod-handler>} object, otherwise not.
27594 @item @code{options}
27595 List of strings or gexps representing the arguments for the database
27596 (@pxref{Databases,,, dico, GNU Dico Manual}).
27600 @defvr {Scheme Variable} %dicod-database:gcide
27601 A @code{<dicod-database>} object serving the GNU Collaborative International
27602 Dictionary of English using the @code{gcide} package.
27605 The following is an example @code{dicod-service} configuration.
27608 (dicod-service #:config
27609 (dicod-configuration
27610 (handlers (list (dicod-handler
27614 (list #~(string-append "dbdir=" #$wordnet))))))
27615 (databases (list (dicod-database
27618 (handler "wordnet")
27619 (options '("database=wn")))
27620 %dicod-database:gcide))))
27624 @subsubheading Docker Service
27626 The @code{(gnu services docker)} module provides the following services.
27628 @defvr {Scheme Variable} docker-service-type
27630 This is the type of the service that runs @url{https://www.docker.com,Docker},
27631 a daemon that can execute application bundles (sometimes referred to as
27632 ``containers'') in isolated environments.
27636 @deftp {Data Type} docker-configuration
27637 This is the data type representing the configuration of Docker and Containerd.
27641 @item @code{package} (default: @code{docker})
27642 The Docker package to use.
27644 @item @code{containerd} (default: @var{containerd})
27645 The Containerd package to use.
27647 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
27648 The Docker user-land networking proxy package to use.
27650 @item @code{enable-proxy?} (default @code{#f})
27651 Enable or disable the use of the Docker user-land networking proxy.
27653 @item @code{debug?} (default @code{#f})
27654 Enable or disable debug output.
27660 @subsubheading Auditd Service
27662 The @code{(gnu services auditd)} module provides the following service.
27664 @defvr {Scheme Variable} auditd-service-type
27666 This is the type of the service that runs
27667 @url{https://people.redhat.com/sgrubb/audit/,auditd},
27668 a daemon that tracks security-relevant information on your system.
27670 Examples of things that can be tracked:
27680 Failed login attempts
27687 @command{auditctl} from the @code{audit} package can be used in order
27688 to add or remove events to be tracked (until the next reboot).
27689 In order to permanently track events, put the command line arguments
27690 of auditctl into a file called @code{audit.rules} in the configuration
27691 directory (see below).
27692 @command{aureport} from the @code{audit} package can be used in order
27693 to view a report of all recorded events.
27694 The audit daemon by default logs into the file
27695 @file{/var/log/audit.log}.
27699 @deftp {Data Type} auditd-configuration
27700 This is the data type representing the configuration of auditd.
27704 @item @code{audit} (default: @code{audit})
27705 The audit package to use.
27707 @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
27708 The directory containing the configuration file for the audit package, which
27709 must be named @code{auditd.conf}, and optionally some audit rules to
27710 instantiate on startup.
27715 @defvr {Scheme Variable} singularity-service-type
27716 This is the type of the service that allows you to run
27717 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
27718 create and run application bundles (aka. ``containers''). The value for this
27719 service is the Singularity package to use.
27721 The service does not install a daemon; instead, it installs helper programs as
27722 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
27723 @command{singularity run} and similar commands.
27727 @subsubheading R-Shiny service
27729 The @code{(gnu services science)} module provides the following service.
27731 @defvr {Scheme Variable} rshiny-service-type
27733 This is a type of service which is used to run a webapp created with
27734 @code{r-shiny}. This service sets the @code{R_LIBS_USER} environment
27735 variable and runs the provided script to call @code{runApp}.
27737 @deftp {Data Type} rshiny-configuration
27738 This is the data type representing the configuration of rshiny.
27742 @item @code{package} (default: @code{r-shiny})
27743 The package to use.
27745 @item @code{binary} (defaunlt @code{"rshiny"})
27746 The name of the binary or shell script located at @code{package/bin/} to
27747 run when the service is run.
27749 The common way to create this file is as follows:
27753 (let* ((out (assoc-ref %outputs "out"))
27754 (targetdir (string-append out "/share/" ,name))
27755 (app (string-append out "/bin/" ,name))
27756 (Rbin (string-append (assoc-ref %build-inputs "r-min")
27759 (mkdir-p (string-append out "/bin"))
27760 (call-with-output-file app
27766 runApp(launch.browser=0, port=4202)~%\n"
27776 @subsubheading Nix service
27778 The @code{(gnu services nix)} module provides the following service.
27780 @defvr {Scheme Variable} nix-service-type
27782 This is the type of the service that runs build daemon of the
27783 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
27787 (use-modules (gnu))
27788 (use-service-modules nix)
27789 (use-package-modules package-management)
27793 (packages (append (list nix)
27796 (services (append (list (service nix-service-type))
27800 After @command{guix system reconfigure} configure Nix for your user:
27803 @item Add a Nix channel and update it. See
27804 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
27806 @item Create a symlink to your profile and activate Nix profile:
27810 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
27811 $ source /run/current-system/profile/etc/profile.d/nix.sh
27816 @deftp {Data Type} nix-configuration
27817 This data type represents the configuration of the Nix daemon.
27820 @item @code{nix} (default: @code{nix})
27821 The Nix package to use.
27823 @item @code{sandbox} (default: @code{#t})
27824 Specifies whether builds are sandboxed by default.
27826 @item @code{build-sandbox-items} (default: @code{'()})
27827 This is a list of strings or objects appended to the
27828 @code{build-sandbox-items} field of the configuration file.
27830 @item @code{extra-config} (default: @code{'()})
27831 This is a list of strings or objects appended to the configuration file.
27832 It is used to pass extra text to be added verbatim to the configuration
27835 @item @code{extra-options} (default: @code{'()})
27836 Extra command line options for @code{nix-service-type}.
27840 @node Setuid Programs
27841 @section Setuid Programs
27843 @cindex setuid programs
27844 Some programs need to run with ``root'' privileges, even when they are
27845 launched by unprivileged users. A notorious example is the
27846 @command{passwd} program, which users can run to change their
27847 password, and which needs to access the @file{/etc/passwd} and
27848 @file{/etc/shadow} files---something normally restricted to root, for
27849 obvious security reasons. To address that, these executables are
27850 @dfn{setuid-root}, meaning that they always run with root privileges
27851 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
27852 for more info about the setuid mechanism).
27854 The store itself @emph{cannot} contain setuid programs: that would be a
27855 security issue since any user on the system can write derivations that
27856 populate the store (@pxref{The Store}). Thus, a different mechanism is
27857 used: instead of changing the setuid bit directly on files that are in
27858 the store, we let the system administrator @emph{declare} which programs
27859 should be setuid root.
27861 The @code{setuid-programs} field of an @code{operating-system}
27862 declaration contains a list of G-expressions denoting the names of
27863 programs to be setuid-root (@pxref{Using the Configuration System}).
27864 For instance, the @command{passwd} program, which is part of the Shadow
27865 package, can be designated by this G-expression (@pxref{G-Expressions}):
27868 #~(string-append #$shadow "/bin/passwd")
27871 A default set of setuid programs is defined by the
27872 @code{%setuid-programs} variable of the @code{(gnu system)} module.
27874 @defvr {Scheme Variable} %setuid-programs
27875 A list of G-expressions denoting common programs that are setuid-root.
27877 The list includes commands such as @command{passwd}, @command{ping},
27878 @command{su}, and @command{sudo}.
27881 Under the hood, the actual setuid programs are created in the
27882 @file{/run/setuid-programs} directory at system activation time. The
27883 files in this directory refer to the ``real'' binaries, which are in the
27886 @node X.509 Certificates
27887 @section X.509 Certificates
27889 @cindex HTTPS, certificates
27890 @cindex X.509 certificates
27892 Web servers available over HTTPS (that is, HTTP over the transport-layer
27893 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
27894 that the client can then use to @emph{authenticate} the server. To do
27895 that, clients verify that the server's certificate is signed by a
27896 so-called @dfn{certificate authority} (CA). But to verify the CA's
27897 signature, clients must have first acquired the CA's certificate.
27899 Web browsers such as GNU@tie{}IceCat include their own set of CA
27900 certificates, such that they are able to verify CA signatures
27903 However, most other programs that can talk HTTPS---@command{wget},
27904 @command{git}, @command{w3m}, etc.---need to be told where CA
27905 certificates can be found.
27907 @cindex @code{nss-certs}
27908 In Guix, this is done by adding a package that provides certificates
27909 to the @code{packages} field of the @code{operating-system} declaration
27910 (@pxref{operating-system Reference}). Guix includes one such package,
27911 @code{nss-certs}, which is a set of CA certificates provided as part of
27912 Mozilla's Network Security Services.
27914 Note that it is @emph{not} part of @code{%base-packages}, so you need to
27915 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
27916 most applications and libraries look for certificates by default, points
27917 to the certificates installed globally.
27919 Unprivileged users, including users of Guix on a foreign distro,
27920 can also install their own certificate package in
27921 their profile. A number of environment variables need to be defined so
27922 that applications and libraries know where to find them. Namely, the
27923 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
27924 variables. Some applications add their own environment variables; for
27925 instance, the Git version control system honors the certificate bundle
27926 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
27927 would typically run something like:
27930 guix install nss-certs
27931 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
27932 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
27933 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
27936 As another example, R requires the @env{CURL_CA_BUNDLE} environment
27937 variable to point to a certificate bundle, so you would have to run
27938 something like this:
27941 guix install nss-certs
27942 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
27945 For other applications you may want to look up the required environment
27946 variable in the relevant documentation.
27949 @node Name Service Switch
27950 @section Name Service Switch
27952 @cindex name service switch
27954 The @code{(gnu system nss)} module provides bindings to the
27955 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
27956 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
27957 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
27958 extended with new ``name'' lookup methods for system databases, which
27959 includes host names, service names, user accounts, and more (@pxref{Name
27960 Service Switch, System Databases and Name Service Switch,, libc, The GNU
27961 C Library Reference Manual}).
27963 The NSS configuration specifies, for each system database, which lookup
27964 method is to be used, and how the various methods are chained
27965 together---for instance, under which circumstances NSS should try the
27966 next method in the list. The NSS configuration is given in the
27967 @code{name-service-switch} field of @code{operating-system} declarations
27968 (@pxref{operating-system Reference, @code{name-service-switch}}).
27971 @cindex .local, host name lookup
27972 As an example, the declaration below configures the NSS to use the
27973 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
27974 back-end}, which supports host name lookups over multicast DNS (mDNS)
27975 for host names ending in @code{.local}:
27978 (name-service-switch
27979 (hosts (list %files ;first, check /etc/hosts
27981 ;; If the above did not succeed, try
27982 ;; with 'mdns_minimal'.
27984 (name "mdns_minimal")
27986 ;; 'mdns_minimal' is authoritative for
27987 ;; '.local'. When it returns "not found",
27988 ;; no need to try the next methods.
27989 (reaction (lookup-specification
27990 (not-found => return))))
27992 ;; Then fall back to DNS.
27996 ;; Finally, try with the "full" 'mdns'.
28001 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
28002 contains this configuration, so you will not have to type it if all you
28003 want is to have @code{.local} host lookup working.
28005 Note that, in this case, in addition to setting the
28006 @code{name-service-switch} of the @code{operating-system} declaration,
28007 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
28008 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
28009 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
28010 to the name service cache daemon (@pxref{Base Services,
28011 @code{nscd-service}}).
28013 For convenience, the following variables provide typical NSS
28016 @defvr {Scheme Variable} %default-nss
28017 This is the default name service switch configuration, a
28018 @code{name-service-switch} object.
28021 @defvr {Scheme Variable} %mdns-host-lookup-nss
28022 This is the name service switch configuration with support for host name
28023 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
28026 The reference for name service switch configuration is given below. It
28027 is a direct mapping of the configuration file format of the C library , so
28028 please refer to the C library manual for more information (@pxref{NSS
28029 Configuration File,,, libc, The GNU C Library Reference Manual}).
28030 Compared to the configuration file format of libc NSS, it has the advantage
28031 not only of adding this warm parenthetic feel that we like, but also
28032 static checks: you will know about syntax errors and typos as soon as you
28033 run @command{guix system}.
28035 @deftp {Data Type} name-service-switch
28037 This is the data type representation the configuration of libc's name
28038 service switch (NSS). Each field below represents one of the supported
28055 The system databases handled by the NSS. Each of these fields must be a
28056 list of @code{<name-service>} objects (see below).
28060 @deftp {Data Type} name-service
28062 This is the data type representing an actual name service and the
28063 associated lookup action.
28067 A string denoting the name service (@pxref{Services in the NSS
28068 configuration,,, libc, The GNU C Library Reference Manual}).
28070 Note that name services listed here must be visible to nscd. This is
28071 achieved by passing the @code{#:name-services} argument to
28072 @code{nscd-service} the list of packages providing the needed name
28073 services (@pxref{Base Services, @code{nscd-service}}).
28076 An action specified using the @code{lookup-specification} macro
28077 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
28078 Reference Manual}). For example:
28081 (lookup-specification (unavailable => continue)
28082 (success => return))
28087 @node Initial RAM Disk
28088 @section Initial RAM Disk
28091 @cindex initial RAM disk
28092 For bootstrapping purposes, the Linux-Libre kernel is passed an
28093 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
28094 root file system as well as an initialization script. The latter is
28095 responsible for mounting the real root file system, and for loading any
28096 kernel modules that may be needed to achieve that.
28098 The @code{initrd-modules} field of an @code{operating-system}
28099 declaration allows you to specify Linux-libre kernel modules that must
28100 be available in the initrd. In particular, this is where you would list
28101 modules needed to actually drive the hard disk where your root partition
28102 is---although the default value of @code{initrd-modules} should cover
28103 most use cases. For example, assuming you need the @code{megaraid_sas}
28104 module in addition to the default modules to be able to access your root
28105 file system, you would write:
28110 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
28113 @defvr {Scheme Variable} %base-initrd-modules
28114 This is the list of kernel modules included in the initrd by default.
28117 Furthermore, if you need lower-level customization, the @code{initrd}
28118 field of an @code{operating-system} declaration allows
28119 you to specify which initrd you would like to use. The @code{(gnu
28120 system linux-initrd)} module provides three ways to build an initrd: the
28121 high-level @code{base-initrd} procedure and the low-level
28122 @code{raw-initrd} and @code{expression->initrd} procedures.
28124 The @code{base-initrd} procedure is intended to cover most common uses.
28125 For example, if you want to add a bunch of kernel modules to be loaded
28126 at boot time, you can define the @code{initrd} field of the operating
28127 system declaration like this:
28130 (initrd (lambda (file-systems . rest)
28131 ;; Create a standard initrd but set up networking
28132 ;; with the parameters QEMU expects by default.
28133 (apply base-initrd file-systems
28134 #:qemu-networking? #t
28138 The @code{base-initrd} procedure also handles common use cases that
28139 involves using the system as a QEMU guest, or as a ``live'' system with
28140 volatile root file system.
28142 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
28143 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
28144 such as trying to guess which kernel modules and packages should be included
28145 to the initrd. An example use of @code{raw-initrd} is when a user has
28146 a custom Linux kernel configuration and default kernel modules included by
28147 @code{base-initrd} are not available.
28149 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
28150 honors several options passed on the Linux kernel command line
28151 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
28152 @code{-append} option of QEMU), notably:
28155 @item --load=@var{boot}
28156 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
28157 program, once it has mounted the root file system.
28159 Guix uses this option to yield control to a boot program that runs the
28160 service activation programs and then spawns the GNU@tie{}Shepherd, the
28161 initialization system.
28163 @item --root=@var{root}
28164 Mount @var{root} as the root file system. @var{root} can be a device
28165 name like @code{/dev/sda1}, a file system label, or a file system UUID.
28166 When unspecified, the device name from the root file system of the
28167 operating system declaration is used.
28169 @item --system=@var{system}
28170 Have @file{/run/booted-system} and @file{/run/current-system} point to
28173 @item modprobe.blacklist=@var{modules}@dots{}
28174 @cindex module, black-listing
28175 @cindex black list, of kernel modules
28176 Instruct the initial RAM disk as well as the @command{modprobe} command
28177 (from the kmod package) to refuse to load @var{modules}. @var{modules}
28178 must be a comma-separated list of module names---e.g.,
28179 @code{usbkbd,9pnet}.
28182 Start a read-eval-print loop (REPL) from the initial RAM disk before it
28183 tries to load kernel modules and to mount the root file system. Our
28184 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
28185 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
28186 Manual}, for more information on Guile's REPL.
28190 Now that you know all the features that initial RAM disks produced by
28191 @code{base-initrd} and @code{raw-initrd} provide,
28192 here is how to use it and customize it further.
28195 @cindex initial RAM disk
28196 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
28197 [#:linux-modules '()] [#:mapped-devices '()] @
28198 [#:keyboard-layout #f] @
28199 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
28200 Return a derivation that builds a raw initrd. @var{file-systems} is
28201 a list of file systems to be mounted by the initrd, possibly in addition to
28202 the root file system specified on the kernel command line via @option{--root}.
28203 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
28204 @var{mapped-devices} is a list of device mappings to realize before
28205 @var{file-systems} are mounted (@pxref{Mapped Devices}).
28206 @var{helper-packages} is a list of packages to be copied in the initrd. It may
28207 include @code{e2fsck/static} or other packages needed by the initrd to check
28208 the root file system.
28210 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
28211 the desired console keyboard layout. This is done before @var{mapped-devices}
28212 are set up and before @var{file-systems} are mounted such that, should the
28213 user need to enter a passphrase or use the REPL, this happens using the
28214 intended keyboard layout.
28216 When @var{qemu-networking?} is true, set up networking with the standard QEMU
28217 parameters. When @var{virtio?} is true, load additional modules so that the
28218 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
28220 When @var{volatile-root?} is true, the root file system is writable but any changes
28224 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
28225 [#:mapped-devices '()] [#:keyboard-layout #f] @
28226 [#:qemu-networking? #f] [#:volatile-root? #f] @
28227 [#:linux-modules '()]
28228 Return as a file-like object a generic initrd, with kernel
28229 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
28230 mounted by the initrd, possibly in addition to the root file system specified
28231 on the kernel command line via @option{--root}. @var{mapped-devices} is a list of device
28232 mappings to realize before @var{file-systems} are mounted.
28234 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
28235 the desired console keyboard layout. This is done before @var{mapped-devices}
28236 are set up and before @var{file-systems} are mounted such that, should the
28237 user need to enter a passphrase or use the REPL, this happens using the
28238 intended keyboard layout.
28240 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
28242 The initrd is automatically populated with all the kernel modules necessary
28243 for @var{file-systems} and for the given options. Additional kernel
28244 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
28245 loaded at boot time in the order in which they appear.
28248 Needless to say, the initrds we produce and use embed a
28249 statically-linked Guile, and the initialization program is a Guile
28250 program. That gives a lot of flexibility. The
28251 @code{expression->initrd} procedure builds such an initrd, given the
28252 program to run in that initrd.
28254 @deffn {Scheme Procedure} expression->initrd @var{exp} @
28255 [#:guile %guile-3.0-static-stripped] [#:name "guile-initrd"]
28256 Return as a file-like object a Linux initrd (a gzipped cpio archive)
28257 containing @var{guile} and that evaluates @var{exp}, a G-expression,
28258 upon booting. All the derivations referenced by @var{exp} are
28259 automatically copied to the initrd.
28262 @node Bootloader Configuration
28263 @section Bootloader Configuration
28266 @cindex boot loader
28268 The operating system supports multiple bootloaders. The bootloader is
28269 configured using @code{bootloader-configuration} declaration. All the
28270 fields of this structure are bootloader agnostic except for one field,
28271 @code{bootloader} that indicates the bootloader to be configured and
28274 Some of the bootloaders do not honor every field of
28275 @code{bootloader-configuration}. For instance, the extlinux
28276 bootloader does not support themes and thus ignores the @code{theme}
28279 @deftp {Data Type} bootloader-configuration
28280 The type of a bootloader configuration declaration.
28284 @item @code{bootloader}
28285 @cindex EFI, bootloader
28286 @cindex UEFI, bootloader
28287 @cindex BIOS, bootloader
28288 The bootloader to use, as a @code{bootloader} object. For now
28289 @code{grub-bootloader}, @code{grub-efi-bootloader},
28290 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
28292 @vindex grub-efi-bootloader
28293 @code{grub-efi-bootloader} allows to boot on modern systems using the
28294 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
28295 use if the installation image contains a @file{/sys/firmware/efi} directory
28296 when you boot it on your system.
28298 @vindex grub-bootloader
28299 @code{grub-bootloader} allows you to boot in particular Intel-based machines
28300 in ``legacy'' BIOS mode.
28302 @cindex ARM, bootloaders
28303 @cindex AArch64, bootloaders
28304 Available bootloaders are described in @code{(gnu bootloader @dots{})}
28305 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
28306 of bootloaders for a wide range of ARM and AArch64 systems, using the
28307 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
28309 @item @code{target}
28310 This is a string denoting the target onto which to install the
28313 The interpretation depends on the bootloader in question. For
28314 @code{grub-bootloader}, for example, it should be a device name understood by
28315 the bootloader @command{installer} command, such as @code{/dev/sda} or
28316 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
28317 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
28318 system, usually @file{/boot/efi}.
28320 @item @code{menu-entries} (default: @code{()})
28321 A possibly empty list of @code{menu-entry} objects (see below), denoting
28322 entries to appear in the bootloader menu, in addition to the current
28323 system entry and the entry pointing to previous system generations.
28325 @item @code{default-entry} (default: @code{0})
28326 The index of the default boot menu entry. Index 0 is for the entry of the
28329 @item @code{timeout} (default: @code{5})
28330 The number of seconds to wait for keyboard input before booting. Set to
28331 0 to boot immediately, and to -1 to wait indefinitely.
28333 @cindex keyboard layout, for the bootloader
28334 @item @code{keyboard-layout} (default: @code{#f})
28335 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
28336 layout, usually US@tie{}English (``qwerty'').
28338 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
28342 This option is currently ignored by bootloaders other than @code{grub} and
28346 @item @code{theme} (default: @var{#f})
28347 The bootloader theme object describing the theme to use. If no theme
28348 is provided, some bootloaders might use a default theme, that's true
28351 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
28352 The output terminals used for the bootloader boot menu, as a list of
28353 symbols. GRUB accepts the values: @code{console}, @code{serial},
28354 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
28355 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
28356 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
28357 configuration,,, grub,GNU GRUB manual}).
28359 @item @code{terminal-inputs} (default: @code{'()})
28360 The input terminals used for the bootloader boot menu, as a list of
28361 symbols. For GRUB, the default is the native platform terminal as
28362 determined at run-time. GRUB accepts the values: @code{console},
28363 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
28364 @code{usb_keyboard}. This field corresponds to the GRUB variable
28365 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
28368 @item @code{serial-unit} (default: @code{#f})
28369 The serial unit used by the bootloader, as an integer from 0 to 3.
28370 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
28371 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
28373 @item @code{serial-speed} (default: @code{#f})
28374 The speed of the serial interface, as an integer. For GRUB, the
28375 default value is chosen at run-time; currently GRUB chooses
28376 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
28383 Should you want to list additional boot menu entries @i{via} the
28384 @code{menu-entries} field above, you will need to create them with the
28385 @code{menu-entry} form. For example, imagine you want to be able to
28386 boot another distro (hard to imagine!), you can define a menu entry
28391 (label "The Other Distro")
28392 (linux "/boot/old/vmlinux-2.6.32")
28393 (linux-arguments '("root=/dev/sda2"))
28394 (initrd "/boot/old/initrd"))
28399 @deftp {Data Type} menu-entry
28400 The type of an entry in the bootloader menu.
28405 The label to show in the menu---e.g., @code{"GNU"}.
28407 @item @code{linux} (default: @code{#f})
28408 The Linux kernel image to boot, for example:
28411 (file-append linux-libre "/bzImage")
28414 For GRUB, it is also possible to specify a device explicitly in the
28415 file path using GRUB's device naming convention (@pxref{Naming
28416 convention,,, grub, GNU GRUB manual}), for example:
28419 "(hd0,msdos1)/boot/vmlinuz"
28422 If the device is specified explicitly as above, then the @code{device}
28423 field is ignored entirely.
28425 @item @code{linux-arguments} (default: @code{()})
28426 The list of extra Linux kernel command-line arguments---e.g.,
28427 @code{("console=ttyS0")}.
28429 @item @code{initrd} (default: @code{#f})
28430 A G-Expression or string denoting the file name of the initial RAM disk
28431 to use (@pxref{G-Expressions}).
28433 @item @code{device} (default: @code{#f})
28434 The device where the kernel and initrd are to be found---i.e., for GRUB,
28435 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
28437 This may be a file system label (a string), a file system UUID (a
28438 bytevector, @pxref{File Systems}), or @code{#f}, in which case
28439 the bootloader will search the device containing the file specified by
28440 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
28441 must @emph{not} be an OS device name such as @file{/dev/sda1}.
28443 @item @code{multiboot-kernel} (default: @code{#f})
28444 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
28445 manual}). When this field is set, a Multiboot menu-entry is generated.
28449 (file-append mach "/boot/gnumach")
28452 @item @code{multiboot-arguments} (default: @code{()})
28453 The list of extra command-line arguments for the multiboot-kernel.
28455 @item @code{multiboot-modules} (default: @code{()})
28456 The list of commands for loading Multiboot modules. For example:
28459 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
28461 (list (file-append libc "/lib/ld.so.1") "exec"
28471 @c FIXME: Write documentation once it's stable.
28472 For now only GRUB has theme support. GRUB themes are created using
28473 the @code{grub-theme} form, which is not fully documented yet.
28475 @deftp {Data Type} grub-theme
28476 Data type representing the configuration of the GRUB theme.
28479 @item @code{gfxmode} (default: @code{'("auto")})
28480 The GRUB @code{gfxmode} to set (a list of screen resolution strings, see
28481 @pxref{gfxmode,,, grub, GNU GRUB manual}).
28485 @deffn {Scheme Procedure} grub-theme
28486 Return the default GRUB theme used by the operating system if no
28487 @code{theme} field is specified in @code{bootloader-configuration}
28490 It comes with a fancy background image displaying the GNU and Guix
28494 For example, to override the default resolution, you may use something
28499 (bootloader-configuration
28502 (inherit (grub-theme))
28503 (gfxmode '("1024x786x32" "auto"))))))
28506 @node Invoking guix system
28507 @section Invoking @code{guix system}
28509 Once you have written an operating system declaration as seen in the
28510 previous section, it can be @dfn{instantiated} using the @command{guix
28511 system} command. The synopsis is:
28514 guix system @var{options}@dots{} @var{action} @var{file}
28517 @var{file} must be the name of a file containing an
28518 @code{operating-system} declaration. @var{action} specifies how the
28519 operating system is instantiated. Currently the following values are
28524 Display available service type definitions that match the given regular
28525 expressions, sorted by relevance:
28531 $ guix system search console
28532 name: console-fonts
28533 location: gnu/services/base.scm:806:2
28534 extends: shepherd-root
28535 description: Install the given fonts on the specified ttys (fonts are per
28536 + virtual console on GNU/Linux). The value of this service is a list of
28537 + tty/font pairs. The font can be the name of a font provided by the `kbd'
28538 + package or any valid argument to `setfont', as in this example:
28540 + '(("tty1" . "LatGrkCyr-8x16")
28541 + ("tty2" . (file-append
28543 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
28544 + ("tty3" . (file-append
28546 + "/share/consolefonts/ter-132n"))) ; for HDPI
28550 location: gnu/services/base.scm:1190:2
28551 extends: shepherd-root
28552 description: Provide console login using the `mingetty' program.
28556 location: gnu/services/base.scm:860:2
28558 description: Provide a console log-in service as specified by its
28559 + configuration value, a `login-configuration' object.
28565 As for @command{guix package --search}, the result is written in
28566 @code{recutils} format, which makes it easy to filter the output
28567 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
28570 Build the operating system described in @var{file}, activate it, and
28571 switch to it@footnote{This action (and the related actions
28572 @code{switch-generation} and @code{roll-back}) are usable only on
28573 systems already running Guix System.}.
28576 @c The paragraph below refers to the problem discussed at
28577 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
28578 It is highly recommended to run @command{guix pull} once before you run
28579 @command{guix system reconfigure} for the first time (@pxref{Invoking
28580 guix pull}). Failing to do that you would see an older version of Guix
28581 once @command{reconfigure} has completed.
28584 This effects all the configuration specified in @var{file}: user
28585 accounts, system services, global package list, setuid programs, etc.
28586 The command starts system services specified in @var{file} that are not
28587 currently running; if a service is currently running this command will
28588 arrange for it to be upgraded the next time it is stopped (e.g.@: by
28589 @code{herd stop X} or @code{herd restart X}).
28591 This command creates a new generation whose number is one greater than
28592 the current generation (as reported by @command{guix system
28593 list-generations}). If that generation already exists, it will be
28594 overwritten. This behavior mirrors that of @command{guix package}
28595 (@pxref{Invoking guix package}).
28597 It also adds a bootloader menu entry for the new OS configuration,
28598 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
28599 entries for older configurations to a submenu, allowing you to choose
28600 an older system generation at boot time should you need it.
28602 @cindex provenance tracking, of the operating system
28603 Upon completion, the new system is deployed under
28604 @file{/run/current-system}. This directory contains @dfn{provenance
28605 meta-data}: the list of channels in use (@pxref{Channels}) and
28606 @var{file} itself, when available. You can view it by running:
28609 guix system describe
28612 This information is useful should you later want to inspect how this
28613 particular generation was built. In fact, assuming @var{file} is
28614 self-contained, you can later rebuild generation @var{n} of your
28615 operating system with:
28618 guix time-machine \
28619 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
28620 system reconfigure \
28621 /var/guix/profiles/system-@var{n}-link/configuration.scm
28624 You can think of it as some sort of built-in version control! Your
28625 system is not just a binary artifact: @emph{it carries its own source}.
28626 @xref{Service Reference, @code{provenance-service-type}}, for more
28627 information on provenance tracking.
28629 By default, @command{reconfigure} @emph{prevents you from downgrading
28630 your system}, which could (re)introduce security vulnerabilities and
28631 also cause problems with ``stateful'' services such as database
28632 management systems. You can override that behavior by passing
28633 @option{--allow-downgrades}.
28635 @item switch-generation
28636 @cindex generations
28637 Switch to an existing system generation. This action atomically
28638 switches the system profile to the specified system generation. It
28639 also rearranges the system's existing bootloader menu entries. It
28640 makes the menu entry for the specified system generation the default,
28641 and it moves the entries for the other generations to a submenu, if
28642 supported by the bootloader being used. The next time the system
28643 boots, it will use the specified system generation.
28645 The bootloader itself is not being reinstalled when using this
28646 command. Thus, the installed bootloader is used with an updated
28647 configuration file.
28649 The target generation can be specified explicitly by its generation
28650 number. For example, the following invocation would switch to system
28654 guix system switch-generation 7
28657 The target generation can also be specified relative to the current
28658 generation with the form @code{+N} or @code{-N}, where @code{+3} means
28659 ``3 generations ahead of the current generation,'' and @code{-1} means
28660 ``1 generation prior to the current generation.'' When specifying a
28661 negative value such as @code{-1}, you must precede it with @code{--} to
28662 prevent it from being parsed as an option. For example:
28665 guix system switch-generation -- -1
28668 Currently, the effect of invoking this action is @emph{only} to switch
28669 the system profile to an existing generation and rearrange the
28670 bootloader menu entries. To actually start using the target system
28671 generation, you must reboot after running this action. In the future,
28672 it will be updated to do the same things as @command{reconfigure},
28673 like activating and deactivating services.
28675 This action will fail if the specified generation does not exist.
28678 @cindex rolling back
28679 Switch to the preceding system generation. The next time the system
28680 boots, it will use the preceding system generation. This is the inverse
28681 of @command{reconfigure}, and it is exactly the same as invoking
28682 @command{switch-generation} with an argument of @code{-1}.
28684 Currently, as with @command{switch-generation}, you must reboot after
28685 running this action to actually start using the preceding system
28688 @item delete-generations
28689 @cindex deleting system generations
28690 @cindex saving space
28691 Delete system generations, making them candidates for garbage collection
28692 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
28695 This works in the same way as @samp{guix package --delete-generations}
28696 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
28697 arguments, all system generations but the current one are deleted:
28700 guix system delete-generations
28703 You can also select the generations you want to delete. The example below
28704 deletes all the system generations that are more than two month old:
28707 guix system delete-generations 2m
28710 Running this command automatically reinstalls the bootloader with an updated
28711 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
28712 longer lists the generations that have been deleted.
28715 Build the derivation of the operating system, which includes all the
28716 configuration files and programs needed to boot and run the system.
28717 This action does not actually install anything.
28720 Populate the given directory with all the files necessary to run the
28721 operating system specified in @var{file}. This is useful for first-time
28722 installations of Guix System. For instance:
28725 guix system init my-os-config.scm /mnt
28728 copies to @file{/mnt} all the store items required by the configuration
28729 specified in @file{my-os-config.scm}. This includes configuration
28730 files, packages, and so on. It also creates other essential files
28731 needed for the system to operate correctly---e.g., the @file{/etc},
28732 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
28734 This command also installs bootloader on the target specified in
28735 @file{my-os-config}, unless the @option{--no-bootloader} option was
28739 @cindex virtual machine
28741 @anchor{guix system vm}
28742 Build a virtual machine that contains the operating system declared in
28743 @var{file}, and return a script to run that virtual machine (VM).
28746 The @code{vm} action and others below
28747 can use KVM support in the Linux-libre kernel. Specifically, if the
28748 machine has hardware virtualization support, the corresponding
28749 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
28750 must exist and be readable and writable by the user and by the
28751 build users of the daemon (@pxref{Build Environment Setup}).
28754 Arguments given to the script are passed to QEMU as in the example
28755 below, which enables networking and requests 1@tie{}GiB of RAM for the
28759 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
28762 The VM shares its store with the host system.
28764 Additional file systems can be shared between the host and the VM using
28765 the @option{--share} and @option{--expose} command-line options: the former
28766 specifies a directory to be shared with write access, while the latter
28767 provides read-only access to the shared directory.
28769 The example below creates a VM in which the user's home directory is
28770 accessible read-only, and where the @file{/exchange} directory is a
28771 read-write mapping of @file{$HOME/tmp} on the host:
28774 guix system vm my-config.scm \
28775 --expose=$HOME --share=$HOME/tmp=/exchange
28778 On GNU/Linux, the default is to boot directly to the kernel; this has
28779 the advantage of requiring only a very tiny root disk image since the
28780 store of the host can then be mounted.
28782 The @option{--full-boot} option forces a complete boot sequence, starting
28783 with the bootloader. This requires more disk space since a root image
28784 containing at least the kernel, initrd, and bootloader data files must
28785 be created. The @option{--image-size} option can be used to specify the
28788 @cindex System images, creation in various formats
28789 @cindex Creating system images in various formats
28792 @itemx docker-image
28793 Return a virtual machine, disk image, or Docker image of the operating
28794 system declared in @var{file} that stands alone. By default,
28795 @command{guix system} estimates the size of the image needed to store
28796 the system, but you can use the @option{--image-size} option to specify
28797 a value. Docker images are built to contain exactly what they need, so
28798 the @option{--image-size} option is ignored in the case of
28799 @code{docker-image}.
28801 You can specify the root file system type by using the
28802 @option{--file-system-type} option. It defaults to @code{ext4}.
28804 When using @code{vm-image}, the returned image is in qcow2 format, which
28805 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
28806 for more information on how to run the image in a virtual machine.
28808 When using @code{disk-image}, a raw disk image is produced; it can be
28809 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
28810 the device corresponding to a USB stick, one can copy the image to it
28811 using the following command:
28814 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc status=progress
28817 When using @code{docker-image}, a Docker image is produced. Guix builds
28818 the image from scratch, not from a pre-existing Docker base image. As a
28819 result, it contains @emph{exactly} what you define in the operating
28820 system configuration file. You can then load the image and launch a
28821 Docker container using commands like the following:
28824 image_id="`docker load < guix-system-docker-image.tar.gz`"
28825 container_id="`docker create $image_id`"
28826 docker start $container_id
28829 This command starts a new Docker container from the specified image. It
28830 will boot the Guix system in the usual manner, which means it will
28831 start any services you have defined in the operating system
28832 configuration. You can get an interactive shell running in the container
28833 using @command{docker exec}:
28836 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
28839 Depending on what you run in the Docker container, it
28840 may be necessary to give the container additional permissions. For
28841 example, if you intend to build software using Guix inside of the Docker
28842 container, you may need to pass the @option{--privileged} option to
28843 @code{docker create}.
28845 Last, the @option{--network} option applies to @command{guix system
28846 docker-image}: it produces an image where network is supposedly shared
28847 with the host, and thus without services like nscd or NetworkManager.
28850 Return a script to run the operating system declared in @var{file}
28851 within a container. Containers are a set of lightweight isolation
28852 mechanisms provided by the kernel Linux-libre. Containers are
28853 substantially less resource-demanding than full virtual machines since
28854 the kernel, shared objects, and other resources can be shared with the
28855 host system; this also means they provide thinner isolation.
28857 Currently, the script must be run as root in order to support more than
28858 a single user and group. The container shares its store with the host
28861 As with the @code{vm} action (@pxref{guix system vm}), additional file
28862 systems to be shared between the host and container can be specified
28863 using the @option{--share} and @option{--expose} options:
28866 guix system container my-config.scm \
28867 --expose=$HOME --share=$HOME/tmp=/exchange
28871 This option requires Linux-libre 3.19 or newer.
28876 @var{options} can contain any of the common build options (@pxref{Common
28877 Build Options}). In addition, @var{options} can contain one of the
28881 @item --expression=@var{expr}
28882 @itemx -e @var{expr}
28883 Consider the operating-system @var{expr} evaluates to.
28884 This is an alternative to specifying a file which evaluates to an
28886 This is used to generate the Guix system installer @pxref{Building the
28887 Installation Image}).
28889 @item --system=@var{system}
28890 @itemx -s @var{system}
28891 Attempt to build for @var{system} instead of the host system type.
28892 This works as per @command{guix build} (@pxref{Invoking guix build}).
28896 Return the derivation file name of the given operating system without
28899 @cindex provenance tracking, of the operating system
28900 @item --save-provenance
28901 As discussed above, @command{guix system init} and @command{guix system
28902 reconfigure} always save provenance information @i{via} a dedicated
28903 service (@pxref{Service Reference, @code{provenance-service-type}}).
28904 However, other commands don't do that by default. If you wish to, say,
28905 create a virtual machine image that contains provenance information, you
28909 guix system vm-image --save-provenance config.scm
28912 That way, the resulting image will effectively ``embed its own source''
28913 in the form of meta-data in @file{/run/current-system}. With that
28914 information, one can rebuild the image to make sure it really contains
28915 what it pretends to contain; or they could use that to derive a variant
28918 @item --file-system-type=@var{type}
28919 @itemx -t @var{type}
28920 For the @code{disk-image} action, create a file system of the given
28921 @var{type} on the image.
28923 When this option is omitted, @command{guix system} uses @code{ext4}.
28925 @cindex ISO-9660 format
28926 @cindex CD image format
28927 @cindex DVD image format
28928 @option{--file-system-type=iso9660} produces an ISO-9660 image, suitable
28929 for burning on CDs and DVDs.
28931 @item --image-size=@var{size}
28932 For the @code{vm-image} and @code{disk-image} actions, create an image
28933 of the given @var{size}. @var{size} may be a number of bytes, or it may
28934 include a unit as a suffix (@pxref{Block size, size specifications,,
28935 coreutils, GNU Coreutils}).
28937 When this option is omitted, @command{guix system} computes an estimate
28938 of the image size as a function of the size of the system declared in
28943 For the @code{container} action, allow containers to access the host network,
28944 that is, do not create a network namespace.
28946 @item --root=@var{file}
28947 @itemx -r @var{file}
28948 Make @var{file} a symlink to the result, and register it as a garbage
28951 @item --skip-checks
28952 Skip pre-installation safety checks.
28954 By default, @command{guix system init} and @command{guix system
28955 reconfigure} perform safety checks: they make sure the file systems that
28956 appear in the @code{operating-system} declaration actually exist
28957 (@pxref{File Systems}), and that any Linux kernel modules that may be
28958 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
28959 RAM Disk}). Passing this option skips these tests altogether.
28961 @item --allow-downgrades
28962 Instruct @command{guix system reconfigure} to allow system downgrades.
28964 By default, @command{reconfigure} prevents you from downgrading your
28965 system. It achieves that by comparing the provenance info of your
28966 system (shown by @command{guix system describe}) with that of your
28967 @command{guix} command (shown by @command{guix describe}). If the
28968 commits for @command{guix} are not descendants of those used for your
28969 system, @command{guix system reconfigure} errors out. Passing
28970 @option{--allow-downgrades} allows you to bypass these checks.
28973 Make sure you understand its security implications before using
28974 @option{--allow-downgrades}.
28978 @cindex on-error strategy
28979 @cindex error strategy
28980 @item --on-error=@var{strategy}
28981 Apply @var{strategy} when an error occurs when reading @var{file}.
28982 @var{strategy} may be one of the following:
28985 @item nothing-special
28986 Report the error concisely and exit. This is the default strategy.
28989 Likewise, but also display a backtrace.
28992 Report the error and enter Guile's debugger. From there, you can run
28993 commands such as @code{,bt} to get a backtrace, @code{,locals} to
28994 display local variable values, and more generally inspect the state of the
28995 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
28996 a list of available debugging commands.
29000 Once you have built, configured, re-configured, and re-re-configured
29001 your Guix installation, you may find it useful to list the operating
29002 system generations available on disk---and that you can choose from the
29003 bootloader boot menu:
29008 Describe the current system generation: its file name, the kernel and
29009 bootloader used, etc., as well as provenance information when available.
29011 @item list-generations
29012 List a summary of each generation of the operating system available on
29013 disk, in a human-readable way. This is similar to the
29014 @option{--list-generations} option of @command{guix package}
29015 (@pxref{Invoking guix package}).
29017 Optionally, one can specify a pattern, with the same syntax that is used
29018 in @command{guix package --list-generations}, to restrict the list of
29019 generations displayed. For instance, the following command displays
29020 generations that are up to 10 days old:
29023 $ guix system list-generations 10d
29028 The @command{guix system} command has even more to offer! The following
29029 sub-commands allow you to visualize how your system services relate to
29032 @anchor{system-extension-graph}
29035 @item extension-graph
29036 Emit in Dot/Graphviz format to standard output the @dfn{service
29037 extension graph} of the operating system defined in @var{file}
29038 (@pxref{Service Composition}, for more information on service
29044 $ guix system extension-graph @var{file} | xdot -
29047 shows the extension relations among services.
29049 @anchor{system-shepherd-graph}
29050 @item shepherd-graph
29051 Emit in Dot/Graphviz format to standard output the @dfn{dependency
29052 graph} of shepherd services of the operating system defined in
29053 @var{file}. @xref{Shepherd Services}, for more information and for an
29058 @node Invoking guix deploy
29059 @section Invoking @code{guix deploy}
29061 We've already seen @code{operating-system} declarations used to manage a
29062 machine's configuration locally. Suppose you need to configure multiple
29063 machines, though---perhaps you're managing a service on the web that's
29064 comprised of several servers. @command{guix deploy} enables you to use those
29065 same @code{operating-system} declarations to manage multiple remote hosts at
29066 once as a logical ``deployment''.
29069 The functionality described in this section is still under development
29070 and is subject to change. Get in touch with us on
29071 @email{guix-devel@@gnu.org}!
29075 guix deploy @var{file}
29078 Such an invocation will deploy the machines that the code within @var{file}
29079 evaluates to. As an example, @var{file} might contain a definition like this:
29082 ;; This is a Guix deployment of a "bare bones" setup, with
29083 ;; no X11 display server, to a machine with an SSH daemon
29084 ;; listening on localhost:2222. A configuration such as this
29085 ;; may be appropriate for virtual machine with ports
29086 ;; forwarded to the host's loopback interface.
29088 (use-service-modules networking ssh)
29089 (use-package-modules bootloaders)
29093 (host-name "gnu-deployed")
29094 (timezone "Etc/UTC")
29095 (bootloader (bootloader-configuration
29096 (bootloader grub-bootloader)
29097 (target "/dev/vda")
29098 (terminal-outputs '(console))))
29099 (file-systems (cons (file-system
29101 (device "/dev/vda1")
29103 %base-file-systems))
29105 (append (list (service dhcp-client-service-type)
29106 (service openssh-service-type
29107 (openssh-configuration
29108 (permit-root-login #t)
29109 (allow-empty-passwords? #t))))
29113 (operating-system %system)
29114 (environment managed-host-environment-type)
29115 (configuration (machine-ssh-configuration
29116 (host-name "localhost")
29117 (system "x86_64-linux")
29119 (identity "./id_rsa")
29123 The file should evaluate to a list of @var{machine} objects. This example,
29124 upon being deployed, will create a new generation on the remote system
29125 realizing the @code{operating-system} declaration @code{%system}.
29126 @code{environment} and @code{configuration} specify how the machine should be
29127 provisioned---that is, how the computing resources should be created and
29128 managed. The above example does not create any resources, as a
29129 @code{'managed-host} is a machine that is already running the Guix system and
29130 available over the network. This is a particularly simple case; a more
29131 complex deployment may involve, for example, starting virtual machines through
29132 a Virtual Private Server (VPS) provider. In such a case, a different
29133 @var{environment} type would be used.
29135 Do note that you first need to generate a key pair on the coordinator machine
29136 to allow the daemon to export signed archives of files from the store
29137 (@pxref{Invoking guix archive}).
29140 # guix archive --generate-key
29144 Each target machine must authorize the key of the master machine so that it
29145 accepts store items it receives from the coordinator:
29148 # guix archive --authorize < coordinator-public-key.txt
29151 @code{user}, in this example, specifies the name of the user account to log in
29152 as to perform the deployment. Its default value is @code{root}, but root
29153 login over SSH may be forbidden in some cases. To work around this,
29154 @command{guix deploy} can log in as an unprivileged user and employ
29155 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
29156 currently installed on the remote and can be invoked non-interactively as
29157 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
29158 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
29159 be accomplished with the following operating system configuration snippet:
29163 (gnu system)) ;for %sudoers-specification
29165 (define %user "username")
29170 (plain-file "sudoers"
29171 (string-append (plain-file-content %sudoers-specification)
29172 (format #f "~a ALL = NOPASSWD: ALL~%"
29177 For more information regarding the format of the @file{sudoers} file,
29178 consult @command{man sudoers}.
29180 @deftp {Data Type} machine
29181 This is the data type representing a single machine in a heterogeneous Guix
29185 @item @code{operating-system}
29186 The object of the operating system configuration to deploy.
29188 @item @code{environment}
29189 An @code{environment-type} describing how the machine should be provisioned.
29191 @item @code{configuration} (default: @code{#f})
29192 An object describing the configuration for the machine's @code{environment}.
29193 If the @code{environment} has a default configuration, @code{#f} may be used.
29194 If @code{#f} is used for an environment with no default configuration,
29195 however, an error will be thrown.
29199 @deftp {Data Type} machine-ssh-configuration
29200 This is the data type representing the SSH client parameters for a machine
29201 with an @code{environment} of @code{managed-host-environment-type}.
29204 @item @code{host-name}
29205 @item @code{build-locally?} (default: @code{#t})
29206 If false, system derivations will be built on the machine being deployed to.
29207 @item @code{system}
29208 The system type describing the architecture of the machine being deployed
29209 to---e.g., @code{"x86_64-linux"}.
29210 @item @code{authorize?} (default: @code{#t})
29211 If true, the coordinator's signing key will be added to the remote's ACL
29213 @item @code{port} (default: @code{22})
29214 @item @code{user} (default: @code{"root"})
29215 @item @code{identity} (default: @code{#f})
29216 If specified, the path to the SSH private key to use to authenticate with the
29219 @item @code{host-key} (default: @code{#f})
29220 This should be the SSH host key of the machine, which looks like this:
29223 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
29226 When @code{host-key} is @code{#f}, the server is authenticated against
29227 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
29230 @item @code{allow-downgrades?} (default: @code{#f})
29231 Whether to allow potential downgrades.
29233 Like @command{guix system reconfigure}, @command{guix deploy} compares
29234 the channel commits currently deployed on the remote host (as returned
29235 by @command{guix system describe}) to those currently in use (as
29236 returned by @command{guix describe}) to determine whether commits
29237 currently in use are descendants of those deployed. When this is not
29238 the case and @code{allow-downgrades?} is false, it raises an error.
29239 This ensures you do not accidentally downgrade remote machines.
29243 @deftp {Data Type} digital-ocean-configuration
29244 This is the data type describing the Droplet that should be created for a
29245 machine with an @code{environment} of @code{digital-ocean-environment-type}.
29248 @item @code{ssh-key}
29249 The path to the SSH private key to use to authenticate with the remote
29250 host. In the future, this field may not exist.
29252 A list of string ``tags'' that uniquely identify the machine. Must be given
29253 such that no two machines in the deployment have the same set of tags.
29254 @item @code{region}
29255 A Digital Ocean region slug, such as @code{"nyc3"}.
29257 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
29258 @item @code{enable-ipv6?}
29259 Whether or not the droplet should be created with IPv6 networking.
29263 @node Running Guix in a VM
29264 @section Running Guix in a Virtual Machine
29266 @cindex virtual machine
29267 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
29269 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
29270 This image is a compressed image in QCOW format. You will first need to
29271 decompress with @command{xz -d}, and then you can pass it to an emulator such
29272 as QEMU (see below for details).
29274 This image boots the Xfce graphical environment and it contains some
29275 commonly-used tools. You can install more software in the image by running
29276 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
29277 also reconfigure the system based on its initial configuration file available
29278 as @file{/run/current-system/configuration.scm} (@pxref{Using the
29279 Configuration System}).
29281 Instead of using this pre-built image, one can also build their own virtual
29282 machine image using @command{guix system vm-image} (@pxref{Invoking guix
29283 system}). The returned image is in qcow2 format, which the
29284 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
29287 If you built your own image, you must copy it out of the store
29288 (@pxref{The Store}) and give yourself permission to write to the copy
29289 before you can use it. When invoking QEMU, you must choose a system
29290 emulator that is suitable for your hardware platform. Here is a minimal
29291 QEMU invocation that will boot the result of @command{guix system
29292 vm-image} on x86_64 hardware:
29295 $ qemu-system-x86_64 \
29296 -nic user,model=virtio-net-pci \
29297 -enable-kvm -m 1024 \
29298 -device virtio-blk,drive=myhd \
29299 -drive if=none,file=/tmp/qemu-image,id=myhd
29302 Here is what each of these options means:
29305 @item qemu-system-x86_64
29306 This specifies the hardware platform to emulate. This should match the
29309 @item -nic user,model=virtio-net-pci
29310 Enable the unprivileged user-mode network stack. The guest OS can
29311 access the host but not vice versa. This is the simplest way to get the
29312 guest OS online. @code{model} specifies which network device to emulate:
29313 @code{virtio-net-pci} is a special device made for virtualized operating
29314 systems and recommended for most uses. Assuming your hardware platform is
29315 x86_64, you can get a list of available NIC models by running
29316 @command{qemu-system-x86_64 -nic model=help}.
29319 If your system has hardware virtualization extensions, enabling the
29320 virtual machine support (KVM) of the Linux kernel will make things run
29323 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
29325 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
29326 which may be insufficient for some operations.
29328 @item -device virtio-blk,drive=myhd
29329 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
29330 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
29331 better performance than if it were emulating a complete disk drive. See the
29332 QEMU and KVM documentation for more info.
29334 @item -drive if=none,file=/tmp/qemu-image,id=myhd
29335 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
29336 the ``myhd'' drive.
29339 The default @command{run-vm.sh} script that is returned by an invocation of
29340 @command{guix system vm} does not add a @command{-nic user} flag by default.
29341 To get network access from within the vm add the @code{(dhcp-client-service)}
29342 to your system definition and start the VM using
29343 @command{`guix system vm config.scm` -nic user}. An important caveat of using
29344 @command{-nic user} for networking is that @command{ping} will not work, because
29345 it uses the ICMP protocol. You'll have to use a different command to check for
29346 network connectivity, for example @command{guix download}.
29348 @subsection Connecting Through SSH
29352 To enable SSH inside a VM you need to add an SSH server like
29353 @code{openssh-service-type} to your VM (@pxref{Networking Services,
29354 @code{openssh-service-type}}). In addition you need to forward the SSH port,
29355 22 by default, to the host. You can do this with
29358 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
29361 To connect to the VM you can run
29364 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
29367 The @command{-p} tells @command{ssh} the port you want to connect to.
29368 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
29369 every time you modify your @command{config.scm} file and the
29370 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
29371 connection to an unknown host every time you connect.
29373 @subsection Using @command{virt-viewer} with Spice
29375 As an alternative to the default @command{qemu} graphical client you can
29376 use the @command{remote-viewer} from the @command{virt-viewer} package. To
29377 connect pass the @command{-spice port=5930,disable-ticketing} flag to
29378 @command{qemu}. See previous section for further information on how to do this.
29380 Spice also allows you to do some nice stuff like share your clipboard with your
29381 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
29384 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
29385 -chardev spicevmc,name=vdagent,id=vdagent
29386 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
29387 name=com.redhat.spice.0
29390 You'll also need to add the @code{(spice-vdagent-service)} to your
29391 system definition (@pxref{Miscellaneous Services, Spice service}).
29393 @node Defining Services
29394 @section Defining Services
29396 The previous sections show the available services and how one can combine
29397 them in an @code{operating-system} declaration. But how do we define
29398 them in the first place? And what is a service anyway?
29401 * Service Composition:: The model for composing services.
29402 * Service Types and Services:: Types and services.
29403 * Service Reference:: API reference.
29404 * Shepherd Services:: A particular type of service.
29407 @node Service Composition
29408 @subsection Service Composition
29412 Here we define a @dfn{service} as, broadly, something that extends the
29413 functionality of the operating system. Often a service is a process---a
29414 @dfn{daemon}---started when the system boots: a secure shell server, a
29415 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
29416 whose execution can be triggered by another daemon---e.g., an FTP server
29417 started by @command{inetd} or a D-Bus service activated by
29418 @command{dbus-daemon}. Occasionally, a service does not map to a
29419 daemon. For instance, the ``account'' service collects user accounts
29420 and makes sure they exist when the system runs; the ``udev'' service
29421 collects device management rules and makes them available to the eudev
29422 daemon; the @file{/etc} service populates the @file{/etc} directory
29425 @cindex service extensions
29426 Guix system services are connected by @dfn{extensions}. For instance, the
29427 secure shell service @emph{extends} the Shepherd---the
29428 initialization system, running as PID@tie{}1---by giving it the command
29429 lines to start and stop the secure shell daemon (@pxref{Networking
29430 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
29431 service by passing it its @file{.service} specification, and extends the
29432 udev service by passing it device management rules (@pxref{Desktop
29433 Services, @code{upower-service}}); the Guix daemon service extends the
29434 Shepherd by passing it the command lines to start and stop the daemon,
29435 and extends the account service by passing it a list of required build
29436 user accounts (@pxref{Base Services}).
29438 All in all, services and their ``extends'' relations form a directed
29439 acyclic graph (DAG). If we represent services as boxes and extensions
29440 as arrows, a typical system might provide something like this:
29442 @image{images/service-graph,,5in,Typical service extension graph.}
29444 @cindex system service
29445 At the bottom, we see the @dfn{system service}, which produces the
29446 directory containing everything to run and boot the system, as returned
29447 by the @command{guix system build} command. @xref{Service Reference},
29448 to learn about the other service types shown here.
29449 @xref{system-extension-graph, the @command{guix system extension-graph}
29450 command}, for information on how to generate this representation for a
29451 particular operating system definition.
29453 @cindex service types
29454 Technically, developers can define @dfn{service types} to express these
29455 relations. There can be any number of services of a given type on the
29456 system---for instance, a system running two instances of the GNU secure
29457 shell server (lsh) has two instances of @code{lsh-service-type}, with
29458 different parameters.
29460 The following section describes the programming interface for service
29461 types and services.
29463 @node Service Types and Services
29464 @subsection Service Types and Services
29466 A @dfn{service type} is a node in the DAG described above. Let us start
29467 with a simple example, the service type for the Guix build daemon
29468 (@pxref{Invoking guix-daemon}):
29471 (define guix-service-type
29475 (list (service-extension shepherd-root-service-type guix-shepherd-service)
29476 (service-extension account-service-type guix-accounts)
29477 (service-extension activation-service-type guix-activation)))
29478 (default-value (guix-configuration))))
29482 It defines three things:
29486 A name, whose sole purpose is to make inspection and debugging easier.
29489 A list of @dfn{service extensions}, where each extension designates the
29490 target service type and a procedure that, given the parameters of the
29491 service, returns a list of objects to extend the service of that type.
29493 Every service type has at least one service extension. The only
29494 exception is the @dfn{boot service type}, which is the ultimate service.
29497 Optionally, a default value for instances of this type.
29500 In this example, @code{guix-service-type} extends three services:
29503 @item shepherd-root-service-type
29504 The @code{guix-shepherd-service} procedure defines how the Shepherd
29505 service is extended. Namely, it returns a @code{<shepherd-service>}
29506 object that defines how @command{guix-daemon} is started and stopped
29507 (@pxref{Shepherd Services}).
29509 @item account-service-type
29510 This extension for this service is computed by @code{guix-accounts},
29511 which returns a list of @code{user-group} and @code{user-account}
29512 objects representing the build user accounts (@pxref{Invoking
29515 @item activation-service-type
29516 Here @code{guix-activation} is a procedure that returns a gexp, which is
29517 a code snippet to run at ``activation time''---e.g., when the service is
29521 A service of this type is instantiated like this:
29524 (service guix-service-type
29525 (guix-configuration
29527 (use-substitutes? #f)))
29530 The second argument to the @code{service} form is a value representing
29531 the parameters of this specific service instance.
29532 @xref{guix-configuration-type, @code{guix-configuration}}, for
29533 information about the @code{guix-configuration} data type. When the
29534 value is omitted, the default value specified by
29535 @code{guix-service-type} is used:
29538 (service guix-service-type)
29541 @code{guix-service-type} is quite simple because it extends other
29542 services but is not extensible itself.
29544 @c @subsubsubsection Extensible Service Types
29546 The service type for an @emph{extensible} service looks like this:
29549 (define udev-service-type
29550 (service-type (name 'udev)
29552 (list (service-extension shepherd-root-service-type
29553 udev-shepherd-service)))
29555 (compose concatenate) ;concatenate the list of rules
29556 (extend (lambda (config rules)
29558 (($ <udev-configuration> udev initial-rules)
29559 (udev-configuration
29560 (udev udev) ;the udev package to use
29561 (rules (append initial-rules rules)))))))))
29564 This is the service type for the
29565 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
29566 management daemon}. Compared to the previous example, in addition to an
29567 extension of @code{shepherd-root-service-type}, we see two new fields:
29571 This is the procedure to @dfn{compose} the list of extensions to
29572 services of this type.
29574 Services can extend the udev service by passing it lists of rules; we
29575 compose those extensions simply by concatenating them.
29578 This procedure defines how the value of the service is @dfn{extended} with
29579 the composition of the extensions.
29581 Udev extensions are composed into a list of rules, but the udev service
29582 value is itself a @code{<udev-configuration>} record. So here, we
29583 extend that record by appending the list of rules it contains to the
29584 list of contributed rules.
29587 This is a string giving an overview of the service type. The string can
29588 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
29589 @command{guix system search} command searches these strings and displays
29590 them (@pxref{Invoking guix system}).
29593 There can be only one instance of an extensible service type such as
29594 @code{udev-service-type}. If there were more, the
29595 @code{service-extension} specifications would be ambiguous.
29597 Still here? The next section provides a reference of the programming
29598 interface for services.
29600 @node Service Reference
29601 @subsection Service Reference
29603 We have seen an overview of service types (@pxref{Service Types and
29604 Services}). This section provides a reference on how to manipulate
29605 services and service types. This interface is provided by the
29606 @code{(gnu services)} module.
29608 @deffn {Scheme Procedure} service @var{type} [@var{value}]
29609 Return a new service of @var{type}, a @code{<service-type>} object (see
29610 below). @var{value} can be any object; it represents the parameters of
29611 this particular service instance.
29613 When @var{value} is omitted, the default value specified by @var{type}
29614 is used; if @var{type} does not specify a default value, an error is
29617 For instance, this:
29620 (service openssh-service-type)
29624 is equivalent to this:
29627 (service openssh-service-type
29628 (openssh-configuration))
29631 In both cases the result is an instance of @code{openssh-service-type}
29632 with the default configuration.
29635 @deffn {Scheme Procedure} service? @var{obj}
29636 Return true if @var{obj} is a service.
29639 @deffn {Scheme Procedure} service-kind @var{service}
29640 Return the type of @var{service}---i.e., a @code{<service-type>} object.
29643 @deffn {Scheme Procedure} service-value @var{service}
29644 Return the value associated with @var{service}. It represents its
29648 Here is an example of how a service is created and manipulated:
29652 (service nginx-service-type
29653 (nginx-configuration
29655 (log-directory log-directory)
29656 (run-directory run-directory)
29657 (file config-file))))
29662 (eq? (service-kind s) nginx-service-type)
29666 The @code{modify-services} form provides a handy way to change the
29667 parameters of some of the services of a list such as
29668 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
29669 evaluates to a list of services. Of course, you could always use
29670 standard list combinators such as @code{map} and @code{fold} to do that
29671 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
29672 @code{modify-services} simply provides a more concise form for this
29675 @deffn {Scheme Syntax} modify-services @var{services} @
29676 (@var{type} @var{variable} => @var{body}) @dots{}
29678 Modify the services listed in @var{services} according to the given
29679 clauses. Each clause has the form:
29682 (@var{type} @var{variable} => @var{body})
29685 where @var{type} is a service type---e.g.,
29686 @code{guix-service-type}---and @var{variable} is an identifier that is
29687 bound within the @var{body} to the service parameters---e.g., a
29688 @code{guix-configuration} instance---of the original service of that
29691 The @var{body} should evaluate to the new service parameters, which will
29692 be used to configure the new service. This new service will replace the
29693 original in the resulting list. Because a service's service parameters
29694 are created using @code{define-record-type*}, you can write a succinct
29695 @var{body} that evaluates to the new service parameters by using the
29696 @code{inherit} feature that @code{define-record-type*} provides.
29698 @xref{Using the Configuration System}, for example usage.
29702 Next comes the programming interface for service types. This is
29703 something you want to know when writing new service definitions, but not
29704 necessarily when simply looking for ways to customize your
29705 @code{operating-system} declaration.
29707 @deftp {Data Type} service-type
29708 @cindex service type
29709 This is the representation of a @dfn{service type} (@pxref{Service Types
29714 This is a symbol, used only to simplify inspection and debugging.
29716 @item @code{extensions}
29717 A non-empty list of @code{<service-extension>} objects (see below).
29719 @item @code{compose} (default: @code{#f})
29720 If this is @code{#f}, then the service type denotes services that cannot
29721 be extended---i.e., services that do not receive ``values'' from other
29724 Otherwise, it must be a one-argument procedure. The procedure is called
29725 by @code{fold-services} and is passed a list of values collected from
29726 extensions. It may return any single value.
29728 @item @code{extend} (default: @code{#f})
29729 If this is @code{#f}, services of this type cannot be extended.
29731 Otherwise, it must be a two-argument procedure: @code{fold-services}
29732 calls it, passing it the initial value of the service as the first
29733 argument and the result of applying @code{compose} to the extension
29734 values as the second argument. It must return a value that is a valid
29735 parameter value for the service instance.
29738 @xref{Service Types and Services}, for examples.
29741 @deffn {Scheme Procedure} service-extension @var{target-type} @
29743 Return a new extension for services of type @var{target-type}.
29744 @var{compute} must be a one-argument procedure: @code{fold-services}
29745 calls it, passing it the value associated with the service that provides
29746 the extension; it must return a valid value for the target service.
29749 @deffn {Scheme Procedure} service-extension? @var{obj}
29750 Return true if @var{obj} is a service extension.
29753 Occasionally, you might want to simply extend an existing service. This
29754 involves creating a new service type and specifying the extension of
29755 interest, which can be verbose; the @code{simple-service} procedure
29756 provides a shorthand for this.
29758 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
29759 Return a service that extends @var{target} with @var{value}. This works
29760 by creating a singleton service type @var{name}, of which the returned
29761 service is an instance.
29763 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
29767 (simple-service 'my-mcron-job mcron-service-type
29768 #~(job '(next-hour (3)) "guix gc -F 2G"))
29772 At the core of the service abstraction lies the @code{fold-services}
29773 procedure, which is responsible for ``compiling'' a list of services
29774 down to a single directory that contains everything needed to boot and
29775 run the system---the directory shown by the @command{guix system build}
29776 command (@pxref{Invoking guix system}). In essence, it propagates
29777 service extensions down the service graph, updating each node parameters
29778 on the way, until it reaches the root node.
29780 @deffn {Scheme Procedure} fold-services @var{services} @
29781 [#:target-type @var{system-service-type}]
29782 Fold @var{services} by propagating their extensions down to the root of
29783 type @var{target-type}; return the root service adjusted accordingly.
29786 Lastly, the @code{(gnu services)} module also defines several essential
29787 service types, some of which are listed below.
29789 @defvr {Scheme Variable} system-service-type
29790 This is the root of the service graph. It produces the system directory
29791 as returned by the @command{guix system build} command.
29794 @defvr {Scheme Variable} boot-service-type
29795 The type of the ``boot service'', which produces the @dfn{boot script}.
29796 The boot script is what the initial RAM disk runs when booting.
29799 @defvr {Scheme Variable} etc-service-type
29800 The type of the @file{/etc} service. This service is used to create
29801 files under @file{/etc} and can be extended by
29802 passing it name/file tuples such as:
29805 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
29808 In this example, the effect would be to add an @file{/etc/issue} file
29809 pointing to the given file.
29812 @defvr {Scheme Variable} setuid-program-service-type
29813 Type for the ``setuid-program service''. This service collects lists of
29814 executable file names, passed as gexps, and adds them to the set of
29815 setuid-root programs on the system (@pxref{Setuid Programs}).
29818 @defvr {Scheme Variable} profile-service-type
29819 Type of the service that populates the @dfn{system profile}---i.e., the
29820 programs under @file{/run/current-system/profile}. Other services can
29821 extend it by passing it lists of packages to add to the system profile.
29824 @cindex provenance tracking, of the operating system
29825 @anchor{provenance-service-type}
29826 @defvr {Scheme Variable} provenance-service-type
29827 This is the type of the service that records @dfn{provenance meta-data}
29828 in the system itself. It creates several files under
29829 @file{/run/current-system}:
29833 This is a ``channel file'' that can be passed to @command{guix pull -C}
29834 or @command{guix time-machine -C}, and which describes the channels used
29835 to build the system, if that information was available
29836 (@pxref{Channels}).
29838 @item configuration.scm
29839 This is the file that was passed as the value for this
29840 @code{provenance-service-type} service. By default, @command{guix
29841 system reconfigure} automatically passes the OS configuration file it
29842 received on the command line.
29845 This contains the same information as the two other files but in a
29846 format that is more readily processable.
29849 In general, these two pieces of information (channels and configuration
29850 file) are enough to reproduce the operating system ``from source''.
29853 This information is necessary to rebuild your operating system, but it
29854 is not always sufficient. In particular, @file{configuration.scm}
29855 itself is insufficient if it is not self-contained---if it refers to
29856 external Guile modules or to extra files. If you want
29857 @file{configuration.scm} to be self-contained, we recommend that modules
29858 or files it refers to be part of a channel.
29860 Besides, provenance meta-data is ``silent'' in the sense that it does
29861 not change the bits contained in your system, @emph{except for the
29862 meta-data bits themselves}. Two different OS configurations or sets of
29863 channels can lead to the same system, bit-for-bit; when
29864 @code{provenance-service-type} is used, these two systems will have
29865 different meta-data and thus different store file names, which makes
29866 comparison less trivial.
29869 This service is automatically added to your operating system
29870 configuration when you use @command{guix system reconfigure},
29871 @command{guix system init}, or @command{guix deploy}.
29874 @node Shepherd Services
29875 @subsection Shepherd Services
29877 @cindex shepherd services
29879 @cindex init system
29880 The @code{(gnu services shepherd)} module provides a way to define
29881 services managed by the GNU@tie{}Shepherd, which is the
29882 initialization system---the first process that is started when the
29883 system boots, also known as PID@tie{}1
29884 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
29886 Services in the Shepherd can depend on each other. For instance, the
29887 SSH daemon may need to be started after the syslog daemon has been
29888 started, which in turn can only happen once all the file systems have
29889 been mounted. The simple operating system defined earlier (@pxref{Using
29890 the Configuration System}) results in a service graph like this:
29892 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
29894 You can actually generate such a graph for any operating system
29895 definition using the @command{guix system shepherd-graph} command
29896 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
29898 The @code{%shepherd-root-service} is a service object representing
29899 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
29900 by passing it lists of @code{<shepherd-service>} objects.
29902 @deftp {Data Type} shepherd-service
29903 The data type representing a service managed by the Shepherd.
29906 @item @code{provision}
29907 This is a list of symbols denoting what the service provides.
29909 These are the names that may be passed to @command{herd start},
29910 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
29911 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
29912 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
29914 @item @code{requirement} (default: @code{'()})
29915 List of symbols denoting the Shepherd services this one depends on.
29917 @cindex one-shot services, for the Shepherd
29918 @item @code{one-shot?} (default: @code{#f})
29919 Whether this service is @dfn{one-shot}. One-shot services stop immediately
29920 after their @code{start} action has completed. @xref{Slots of services,,,
29921 shepherd, The GNU Shepherd Manual}, for more info.
29923 @item @code{respawn?} (default: @code{#t})
29924 Whether to restart the service when it stops, for instance when the
29925 underlying process dies.
29928 @itemx @code{stop} (default: @code{#~(const #f)})
29929 The @code{start} and @code{stop} fields refer to the Shepherd's
29930 facilities to start and stop processes (@pxref{Service De- and
29931 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
29932 G-expressions that get expanded in the Shepherd configuration file
29933 (@pxref{G-Expressions}).
29935 @item @code{actions} (default: @code{'()})
29936 @cindex actions, of Shepherd services
29937 This is a list of @code{shepherd-action} objects (see below) defining
29938 @dfn{actions} supported by the service, in addition to the standard
29939 @code{start} and @code{stop} actions. Actions listed here become available as
29940 @command{herd} sub-commands:
29943 herd @var{action} @var{service} [@var{arguments}@dots{}]
29946 @item @code{auto-start?} (default: @code{#t})
29947 Whether this service should be started automatically by the Shepherd. If it
29948 is @code{#f} the service has to be started manually with @code{herd start}.
29950 @item @code{documentation}
29951 A documentation string, as shown when running:
29954 herd doc @var{service-name}
29957 where @var{service-name} is one of the symbols in @code{provision}
29958 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
29960 @item @code{modules} (default: @code{%default-modules})
29961 This is the list of modules that must be in scope when @code{start} and
29962 @code{stop} are evaluated.
29967 @deftp {Data Type} shepherd-action
29968 This is the data type that defines additional actions implemented by a
29969 Shepherd service (see above).
29973 Symbol naming the action.
29975 @item documentation
29976 This is a documentation string for the action. It can be viewed by running:
29979 herd doc @var{service} action @var{action}
29983 This should be a gexp that evaluates to a procedure of at least one argument,
29984 which is the ``running value'' of the service (@pxref{Slots of services,,,
29985 shepherd, The GNU Shepherd Manual}).
29988 The following example defines an action called @code{say-hello} that kindly
29994 (documentation "Say hi!")
29995 (procedure #~(lambda (running . args)
29996 (format #t "Hello, friend! arguments: ~s\n"
30001 Assuming this action is added to the @code{example} service, then you can do:
30004 # herd say-hello example
30005 Hello, friend! arguments: ()
30006 # herd say-hello example a b c
30007 Hello, friend! arguments: ("a" "b" "c")
30010 This, as you can see, is a fairly sophisticated way to say hello.
30011 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
30015 @defvr {Scheme Variable} shepherd-root-service-type
30016 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
30018 This is the service type that extensions target when they want to create
30019 shepherd services (@pxref{Service Types and Services}, for an example).
30020 Each extension must pass a list of @code{<shepherd-service>}.
30023 @defvr {Scheme Variable} %shepherd-root-service
30024 This service represents PID@tie{}1.
30028 @node Documentation
30029 @chapter Documentation
30031 @cindex documentation, searching for
30032 @cindex searching for documentation
30033 @cindex Info, documentation format
30035 @cindex manual pages
30036 In most cases packages installed with Guix come with documentation.
30037 There are two main documentation formats: ``Info'', a browseable
30038 hypertext format used for GNU software, and ``manual pages'' (or ``man
30039 pages''), the linear documentation format traditionally found on Unix.
30040 Info manuals are accessed with the @command{info} command or with Emacs,
30041 and man pages are accessed using @command{man}.
30043 You can look for documentation of software installed on your system by
30044 keyword. For example, the following command searches for information
30045 about ``TLS'' in Info manuals:
30049 "(emacs)Network Security" -- STARTTLS
30050 "(emacs)Network Security" -- TLS
30051 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
30052 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
30057 The command below searches for the same keyword in man pages:
30061 SSL (7) - OpenSSL SSL/TLS library
30062 certtool (1) - GnuTLS certificate tool
30066 These searches are purely local to your computer so you have the
30067 guarantee that documentation you find corresponds to what you have
30068 actually installed, you can access it off-line, and your privacy is
30071 Once you have these results, you can view the relevant documentation by
30075 $ info "(gnutls)Core TLS API"
30085 Info manuals contain sections and indices as well as hyperlinks like
30086 those found in Web pages. The @command{info} reader (@pxref{Top, Info
30087 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
30088 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
30089 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
30090 Introduction}, for an introduction to Info navigation.
30092 @node Installing Debugging Files
30093 @chapter Installing Debugging Files
30095 @cindex debugging files
30096 Program binaries, as produced by the GCC compilers for instance, are
30097 typically written in the ELF format, with a section containing
30098 @dfn{debugging information}. Debugging information is what allows the
30099 debugger, GDB, to map binary code to source code; it is required to
30100 debug a compiled program in good conditions.
30102 The problem with debugging information is that is takes up a fair amount
30103 of disk space. For example, debugging information for the GNU C Library
30104 weighs in at more than 60 MiB. Thus, as a user, keeping all the
30105 debugging info of all the installed programs is usually not an option.
30106 Yet, space savings should not come at the cost of an impediment to
30107 debugging---especially in the GNU system, which should make it easier
30108 for users to exert their computing freedom (@pxref{GNU Distribution}).
30110 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
30111 mechanism that allows users to get the best of both worlds: debugging
30112 information can be stripped from the binaries and stored in separate
30113 files. GDB is then able to load debugging information from those files,
30114 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
30117 The GNU distribution takes advantage of this by storing debugging
30118 information in the @code{lib/debug} sub-directory of a separate package
30119 output unimaginatively called @code{debug} (@pxref{Packages with
30120 Multiple Outputs}). Users can choose to install the @code{debug} output
30121 of a package when they need it. For instance, the following command
30122 installs the debugging information for the GNU C Library and for GNU
30126 guix install glibc:debug guile:debug
30129 GDB must then be told to look for debug files in the user's profile, by
30130 setting the @code{debug-file-directory} variable (consider setting it
30131 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
30135 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
30138 From there on, GDB will pick up debugging information from the
30139 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
30141 In addition, you will most likely want GDB to be able to show the source
30142 code being debugged. To do that, you will have to unpack the source
30143 code of the package of interest (obtained with @code{guix build
30144 --source}, @pxref{Invoking guix build}), and to point GDB to that source
30145 directory using the @code{directory} command (@pxref{Source Path,
30146 @code{directory},, gdb, Debugging with GDB}).
30148 @c XXX: keep me up-to-date
30149 The @code{debug} output mechanism in Guix is implemented by the
30150 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
30151 opt-in---debugging information is available only for the packages
30152 with definitions explicitly declaring a @code{debug} output. This may be
30153 changed to opt-out in the future if our build farm servers can handle
30154 the load. To check whether a package has a @code{debug} output, use
30155 @command{guix package --list-available} (@pxref{Invoking guix package}).
30158 @node Security Updates
30159 @chapter Security Updates
30161 @cindex security updates
30162 @cindex security vulnerabilities
30163 Occasionally, important security vulnerabilities are discovered in software
30164 packages and must be patched. Guix developers try hard to keep track of
30165 known vulnerabilities and to apply fixes as soon as possible in the
30166 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
30167 containing only security updates). The @command{guix lint} tool helps
30168 developers find out about vulnerable versions of software packages in the
30173 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
30174 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
30175 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
30179 @xref{Invoking guix lint}, for more information.
30181 Guix follows a functional
30182 package management discipline (@pxref{Introduction}), which implies
30183 that, when a package is changed, @emph{every package that depends on it}
30184 must be rebuilt. This can significantly slow down the deployment of
30185 fixes in core packages such as libc or Bash, since basically the whole
30186 distribution would need to be rebuilt. Using pre-built binaries helps
30187 (@pxref{Substitutes}), but deployment may still take more time than
30191 To address this, Guix implements @dfn{grafts}, a mechanism that allows
30192 for fast deployment of critical updates without the costs associated
30193 with a whole-distribution rebuild. The idea is to rebuild only the
30194 package that needs to be patched, and then to ``graft'' it onto packages
30195 explicitly installed by the user and that were previously referring to
30196 the original package. The cost of grafting is typically very low, and
30197 order of magnitudes lower than a full rebuild of the dependency chain.
30199 @cindex replacements of packages, for grafts
30200 For instance, suppose a security update needs to be applied to Bash.
30201 Guix developers will provide a package definition for the ``fixed''
30202 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
30203 Packages}). Then, the original package definition is augmented with a
30204 @code{replacement} field pointing to the package containing the bug fix:
30211 (replacement bash-fixed)))
30214 From there on, any package depending directly or indirectly on Bash---as
30215 reported by @command{guix gc --requisites} (@pxref{Invoking guix
30216 gc})---that is installed is automatically ``rewritten'' to refer to
30217 @code{bash-fixed} instead of @code{bash}. This grafting process takes
30218 time proportional to the size of the package, usually less than a
30219 minute for an ``average'' package on a recent machine. Grafting is
30220 recursive: when an indirect dependency requires grafting, then grafting
30221 ``propagates'' up to the package that the user is installing.
30223 Currently, the length of the name and version of the graft and that of
30224 the package it replaces (@code{bash-fixed} and @code{bash} in the example
30225 above) must be equal. This restriction mostly comes from the fact that
30226 grafting works by patching files, including binary files, directly.
30227 Other restrictions may apply: for instance, when adding a graft to a
30228 package providing a shared library, the original shared library and its
30229 replacement must have the same @code{SONAME} and be binary-compatible.
30231 The @option{--no-grafts} command-line option allows you to forcefully
30232 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
30236 guix build bash --no-grafts
30240 returns the store file name of the original Bash, whereas:
30247 returns the store file name of the ``fixed'', replacement Bash. This
30248 allows you to distinguish between the two variants of Bash.
30250 To verify which Bash your whole profile refers to, you can run
30251 (@pxref{Invoking guix gc}):
30254 guix gc -R `readlink -f ~/.guix-profile` | grep bash
30258 @dots{} and compare the store file names that you get with those above.
30259 Likewise for a complete Guix system generation:
30262 guix gc -R `guix system build my-config.scm` | grep bash
30265 Lastly, to check which Bash running processes are using, you can use the
30266 @command{lsof} command:
30269 lsof | grep /gnu/store/.*bash
30273 @node Bootstrapping
30274 @chapter Bootstrapping
30276 @c Adapted from the ELS 2013 paper.
30278 @cindex bootstrapping
30280 Bootstrapping in our context refers to how the distribution gets built
30281 ``from nothing''. Remember that the build environment of a derivation
30282 contains nothing but its declared inputs (@pxref{Introduction}). So
30283 there's an obvious chicken-and-egg problem: how does the first package
30284 get built? How does the first compiler get compiled? Note that this is
30285 a question of interest only to the curious hacker, not to the regular
30286 user, so you can shamelessly skip this section if you consider yourself
30287 a ``regular user''.
30289 @cindex bootstrap binaries
30290 The GNU system is primarily made of C code, with libc at its core. The
30291 GNU build system itself assumes the availability of a Bourne shell and
30292 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
30293 `grep'. Furthermore, build programs---programs that run
30294 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
30295 (@pxref{Derivations}). Consequently, to be able to build anything at
30296 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
30297 Binutils, libc, and the other packages mentioned above---the
30298 @dfn{bootstrap binaries}.
30300 These bootstrap binaries are ``taken for granted'', though we can also
30301 re-create them if needed (@pxref{Preparing to Use the Bootstrap
30305 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
30306 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
30309 @node Reduced Binary Seed Bootstrap
30310 @section The Reduced Binary Seed Bootstrap
30312 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
30313 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
30314 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
30315 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
30316 ``taken for granted.''
30318 Taking the bootstrap binaries for granted means that we consider them to
30319 be a correct and trustworthy ``seed'' for building the complete system.
30320 Therein lies a problem: the combined size of these bootstrap binaries is
30321 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
30322 or even inspecting these is next to impossible.
30324 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
30325 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
30326 Source Bootstrap'' and while we are working towards that goal it would
30327 be hyperbole to use that term for what we do now.}.
30329 The Reduced Binary Seed bootstrap removes the most critical tools---from a
30330 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
30331 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
30332 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
30333 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
30335 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
30336 C Library are built from source. From here on the more traditional
30337 bootstrap process resumes. This approach has reduced the bootstrap
30338 binaries in size to about 145MB in Guix v1.1.
30340 The next step that Guix has taken is to replace the shell and all its
30341 utilities with implementations in Guile Scheme, the @emph{Scheme-only
30342 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
30343 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
30344 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
30345 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
30346 removed are now built from source.
30348 Building the GNU System from source is currently only possibly by adding
30349 some historical GNU packages as intermediate steps@footnote{Packages
30350 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
30351 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
30352 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
30353 and GNU packages become more bootstrappable again (e.g., new releases of
30354 GNU Sed will also ship as gzipped tarballs again, as alternative to the
30355 hard to bootstrap @code{xz}-compression), this set of added packages can
30356 hopefully be reduced again.
30358 The graph below shows the resulting dependency graph for
30359 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
30360 traditional bootstrap of the rest of the Guix System.
30362 @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
30363 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
30365 The only significant binary bootstrap seeds that remain@footnote{
30366 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
30367 together with @code{mes}.} are a Scheme intepreter and a Scheme
30368 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
30369 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
30370 to get Guile running.}.
30372 This further reduction has brought down the size of the binary seed to
30373 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
30375 Work is ongoing to remove all binary blobs from our free software
30376 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
30377 is work to bring these bootstraps to the @code{arm-linux} and
30378 @code{aarch64-linux} architectures and to the Hurd.
30380 If you are interested, join us on @samp{#bootstrappable} on the Freenode
30381 IRC network or discuss on @email{bug-mes@@gnu.org} or
30382 @email{gash-devel@@nongnu.org}.
30384 @node Preparing to Use the Bootstrap Binaries
30385 @section Preparing to Use the Bootstrap Binaries
30387 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
30388 @c large image, it's hard to scroll. Oh well.
30389 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
30391 The figure above shows the very beginning of the dependency graph of the
30392 distribution, corresponding to the package definitions of the @code{(gnu
30393 packages bootstrap)} module. A similar figure can be generated with
30394 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
30397 guix graph -t derivation \
30398 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
30399 | dot -Tps > gcc.ps
30402 or, for the further Reduced Binary Seed bootstrap
30405 guix graph -t derivation \
30406 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
30407 | dot -Tps > mes.ps
30410 At this level of detail, things are
30411 slightly complex. First, Guile itself consists of an ELF executable,
30412 along with many source and compiled Scheme files that are dynamically
30413 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
30414 tarball shown in this graph. This tarball is part of Guix's ``source''
30415 distribution, and gets inserted into the store with @code{add-to-store}
30416 (@pxref{The Store}).
30418 But how do we write a derivation that unpacks this tarball and adds it
30419 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
30420 derivation---the first one that gets built---uses @code{bash} as its
30421 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
30422 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
30423 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
30424 the Guix source distribution, whose sole purpose is to allow the Guile
30425 tarball to be unpacked.
30427 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
30428 Guile that can be used to run subsequent build programs. Its first task
30429 is to download tarballs containing the other pre-built binaries---this
30430 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
30431 @code{ftp-client.scm} are used for this purpose. The
30432 @code{module-import.drv} derivations import those modules in a directory
30433 in the store, using the original layout. The
30434 @code{module-import-compiled.drv} derivations compile those modules, and
30435 write them in an output directory with the right layout. This
30436 corresponds to the @code{#:modules} argument of
30437 @code{build-expression->derivation} (@pxref{Derivations}).
30439 Finally, the various tarballs are unpacked by the derivations
30440 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
30441 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
30442 point we have a working C tool chain.
30444 @unnumberedsec Building the Build Tools
30446 Bootstrapping is complete when we have a full tool chain that does not
30447 depend on the pre-built bootstrap tools discussed above. This
30448 no-dependency requirement is verified by checking whether the files of
30449 the final tool chain contain references to the @file{/gnu/store}
30450 directories of the bootstrap inputs. The process that leads to this
30451 ``final'' tool chain is described by the package definitions found in
30452 the @code{(gnu packages commencement)} module.
30454 The @command{guix graph} command allows us to ``zoom out'' compared to
30455 the graph above, by looking at the level of package objects instead of
30456 individual derivations---remember that a package may translate to
30457 several derivations, typically one derivation to download its source,
30458 one to build the Guile modules it needs, and one to actually build the
30459 package from source. The command:
30462 guix graph -t bag \
30463 -e '(@@@@ (gnu packages commencement)
30464 glibc-final-with-bootstrap-bash)' | xdot -
30468 displays the dependency graph leading to the ``final'' C
30469 library@footnote{You may notice the @code{glibc-intermediate} label,
30470 suggesting that it is not @emph{quite} final, but as a good
30471 approximation, we will consider it final.}, depicted below.
30473 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
30475 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
30476 The first tool that gets built with the bootstrap binaries is
30477 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
30478 for all the following packages. From there Findutils and Diffutils get
30481 Then come the first-stage Binutils and GCC, built as pseudo cross
30482 tools---i.e., with @option{--target} equal to @option{--host}. They are
30483 used to build libc. Thanks to this cross-build trick, this libc is
30484 guaranteed not to hold any reference to the initial tool chain.
30486 From there the final Binutils and GCC (not shown above) are built. GCC
30487 uses @command{ld} from the final Binutils, and links programs against
30488 the just-built libc. This tool chain is used to build the other
30489 packages used by Guix and by the GNU Build System: Guile, Bash,
30492 And voilà! At this point we have the complete set of build tools that
30493 the GNU Build System expects. These are in the @code{%final-inputs}
30494 variable of the @code{(gnu packages commencement)} module, and are
30495 implicitly used by any package that uses @code{gnu-build-system}
30496 (@pxref{Build Systems, @code{gnu-build-system}}).
30499 @unnumberedsec Building the Bootstrap Binaries
30501 @cindex bootstrap binaries
30502 Because the final tool chain does not depend on the bootstrap binaries,
30503 those rarely need to be updated. Nevertheless, it is useful to have an
30504 automated way to produce them, should an update occur, and this is what
30505 the @code{(gnu packages make-bootstrap)} module provides.
30507 The following command builds the tarballs containing the bootstrap binaries
30508 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
30509 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
30510 and Guile, and a tarball containing a mixture of Coreutils and other basic
30511 command-line tools):
30514 guix build bootstrap-tarballs
30517 The generated tarballs are those that should be referred to in the
30518 @code{(gnu packages bootstrap)} module mentioned at the beginning of
30521 Still here? Then perhaps by now you've started to wonder: when do we
30522 reach a fixed point? That is an interesting question! The answer is
30523 unknown, but if you would like to investigate further (and have
30524 significant computational and storage resources to do so), then let us
30527 @unnumberedsec Reducing the Set of Bootstrap Binaries
30529 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
30530 binary code! Why is that a problem? It's a problem because these big chunks
30531 of binary code are practically non-auditable, which makes it hard to establish
30532 what source code produced them. Every unauditable binary also leaves us
30533 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
30534 paper @emph{Reflections on Trusting Trust}.
30536 This is mitigated by the fact that our bootstrap binaries were generated
30537 from an earlier Guix revision. Nevertheless it lacks the level of
30538 transparency that we get in the rest of the package dependency graph,
30539 where Guix always gives us a source-to-binary mapping. Thus, our goal
30540 is to reduce the set of bootstrap binaries to the bare minimum.
30542 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
30543 on-going projects to do that. One of these is about replacing the
30544 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
30545 of increasing complexity, which could be built from source starting from
30546 a simple and auditable assembler.
30548 Our first major achievement is the replacement of of GCC, the GNU C Library
30549 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
30550 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
30551 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
30552 bootstrapped yet and thus we inject them as binary seeds. We call this the
30553 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
30554 binaries! Also, it has eliminated the C compiler binary; i686-linux and
30555 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
30557 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
30558 also looking at any other bootstrap binaries. Your help is welcome!
30561 @chapter Porting to a New Platform
30563 As discussed above, the GNU distribution is self-contained, and
30564 self-containment is achieved by relying on pre-built ``bootstrap
30565 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
30566 operating system kernel, CPU architecture, and application binary
30567 interface (ABI). Thus, to port the distribution to a platform that is
30568 not yet supported, one must build those bootstrap binaries, and update
30569 the @code{(gnu packages bootstrap)} module to use them on that platform.
30571 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
30572 When everything goes well, and assuming the GNU tool chain supports the
30573 target platform, this can be as simple as running a command like this
30577 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
30580 For this to work, the @code{glibc-dynamic-linker} procedure in
30581 @code{(gnu packages bootstrap)} must be augmented to return the right
30582 file name for libc's dynamic linker on that platform; likewise,
30583 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
30584 taught about the new platform.
30586 Once these are built, the @code{(gnu packages bootstrap)} module needs
30587 to be updated to refer to these binaries on the target platform. That
30588 is, the hashes and URLs of the bootstrap tarballs for the new platform
30589 must be added alongside those of the currently supported platforms. The
30590 bootstrap Guile tarball is treated specially: it is expected to be
30591 available locally, and @file{gnu/local.mk} has rules to download it for
30592 the supported architectures; a rule for the new platform must be added
30595 In practice, there may be some complications. First, it may be that the
30596 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
30597 above) is not recognized by all the GNU tools. Typically, glibc
30598 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
30599 configure flag (see @code{gcc.scm} for examples of how to handle this).
30600 Second, some of the required packages could fail to build for that
30601 platform. Lastly, the generated binaries could be broken for some
30604 @c *********************************************************************
30605 @include contributing.texi
30607 @c *********************************************************************
30608 @node Acknowledgments
30609 @chapter Acknowledgments
30611 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
30612 which was designed and
30613 implemented by Eelco Dolstra, with contributions from other people (see
30614 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
30615 management, and promoted unprecedented features, such as transactional
30616 package upgrades and rollbacks, per-user profiles, and referentially
30617 transparent build processes. Without this work, Guix would not exist.
30619 The Nix-based software distributions, Nixpkgs and NixOS, have also been
30620 an inspiration for Guix.
30622 GNU@tie{}Guix itself is a collective work with contributions from a
30623 number of people. See the @file{AUTHORS} file in Guix for more
30624 information on these fine people. The @file{THANKS} file lists people
30625 who have helped by reporting bugs, taking care of the infrastructure,
30626 providing artwork and themes, making suggestions, and more---thank you!
30629 @c *********************************************************************
30630 @node GNU Free Documentation License
30631 @appendix GNU Free Documentation License
30632 @cindex license, GNU Free Documentation License
30633 @include fdl-1.3.texi
30635 @c *********************************************************************
30636 @node Concept Index
30637 @unnumbered Concept Index
30640 @node Programming Index
30641 @unnumbered Programming Index
30642 @syncodeindex tp fn
30643 @syncodeindex vr fn
30648 @c Local Variables:
30649 @c ispell-local-dictionary: "american";