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 0.12.0 for 'userauth-gssapi!'.
795 Support for build offloading (@pxref{Daemon Offload Setup}) and
796 @command{guix copy} (@pxref{Invoking guix copy}) depends on
797 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
798 version 0.12.0 or later.
801 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
802 substitutes can be used and @command{guix publish} can compress substitutes
806 When @url{http://www.bzip.org, libbz2} is available,
807 @command{guix-daemon} can use it to compress build logs.
810 Unless @option{--disable-daemon} was passed to @command{configure}, the
811 following packages are also needed:
814 @item @url{https://gnupg.org/, GNU libgcrypt};
815 @item @url{https://sqlite.org, SQLite 3};
816 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
820 @cindex state directory
821 When configuring Guix on a system that already has a Guix installation,
822 be sure to specify the same state directory as the existing installation
823 using the @option{--localstatedir} option of the @command{configure}
824 script (@pxref{Directory Variables, @code{localstatedir},, standards,
825 GNU Coding Standards}). Usually, this @var{localstatedir} option is
826 set to the value @file{/var}. The @command{configure} script protects
827 against unintended misconfiguration of @var{localstatedir} so you do not
828 inadvertently corrupt your store (@pxref{The Store}).
830 @node Running the Test Suite
831 @section Running the Test Suite
834 After a successful @command{configure} and @code{make} run, it is a good
835 idea to run the test suite. It can help catch issues with the setup or
836 environment, or bugs in Guix itself---and really, reporting test
837 failures is a good way to help improve the software. To run the test
844 Test cases can run in parallel: you can use the @code{-j} option of
845 GNU@tie{}make to speed things up. The first run may take a few minutes
846 on a recent machine; subsequent runs will be faster because the store
847 that is created for test purposes will already have various things in
850 It is also possible to run a subset of the tests by defining the
851 @code{TESTS} makefile variable as in this example:
854 make check TESTS="tests/store.scm tests/cpio.scm"
857 By default, tests results are displayed at a file level. In order to
858 see the details of every individual test cases, it is possible to define
859 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
862 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
865 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
866 @file{test-suite.log} file. Please specify the Guix version being used
867 as well as version numbers of the dependencies (@pxref{Requirements}) in
870 Guix also comes with a whole-system test suite that tests complete
871 Guix System instances. It can only run on systems where
872 Guix is already installed, using:
879 or, again, by defining @code{TESTS} to select a subset of tests to run:
882 make check-system TESTS="basic mcron"
885 These system tests are defined in the @code{(gnu tests @dots{})}
886 modules. They work by running the operating systems under test with
887 lightweight instrumentation in a virtual machine (VM). They can be
888 computationally intensive or rather cheap, depending on whether
889 substitutes are available for their dependencies (@pxref{Substitutes}).
890 Some of them require a lot of storage space to hold VM images.
892 Again in case of test failures, please send @email{bug-guix@@gnu.org}
895 @node Setting Up the Daemon
896 @section Setting Up the Daemon
899 Operations such as building a package or running the garbage collector
900 are all performed by a specialized process, the @dfn{build daemon}, on
901 behalf of clients. Only the daemon may access the store and its
902 associated database. Thus, any operation that manipulates the store
903 goes through the daemon. For instance, command-line tools such as
904 @command{guix package} and @command{guix build} communicate with the
905 daemon (@i{via} remote procedure calls) to instruct it what to do.
907 The following sections explain how to prepare the build daemon's
908 environment. See also @ref{Substitutes}, for information on how to allow
909 the daemon to download pre-built binaries.
912 * Build Environment Setup:: Preparing the isolated build environment.
913 * Daemon Offload Setup:: Offloading builds to remote machines.
914 * SELinux Support:: Using an SELinux policy for the daemon.
917 @node Build Environment Setup
918 @subsection Build Environment Setup
920 @cindex build environment
921 In a standard multi-user setup, Guix and its daemon---the
922 @command{guix-daemon} program---are installed by the system
923 administrator; @file{/gnu/store} is owned by @code{root} and
924 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
925 Guix tools to build packages or otherwise access the store, and the
926 daemon will do it on their behalf, ensuring that the store is kept in a
927 consistent state, and allowing built packages to be shared among users.
930 When @command{guix-daemon} runs as @code{root}, you may not want package
931 build processes themselves to run as @code{root} too, for obvious
932 security reasons. To avoid that, a special pool of @dfn{build users}
933 should be created for use by build processes started by the daemon.
934 These build users need not have a shell and a home directory: they will
935 just be used when the daemon drops @code{root} privileges in build
936 processes. Having several such users allows the daemon to launch
937 distinct build processes under separate UIDs, which guarantees that they
938 do not interfere with each other---an essential feature since builds are
939 regarded as pure functions (@pxref{Introduction}).
941 On a GNU/Linux system, a build user pool may be created like this (using
942 Bash syntax and the @code{shadow} commands):
944 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
945 @c for why `-G' is needed.
947 # groupadd --system guixbuild
948 # for i in `seq -w 1 10`;
950 useradd -g guixbuild -G guixbuild \
951 -d /var/empty -s `which nologin` \
952 -c "Guix build user $i" --system \
958 The number of build users determines how many build jobs may run in
959 parallel, as specified by the @option{--max-jobs} option
960 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
961 @command{guix system vm} and related commands, you may need to add the
962 build users to the @code{kvm} group so they can access @file{/dev/kvm},
963 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
964 (@pxref{Invoking guix system}).
966 The @code{guix-daemon} program may then be run as @code{root} with the
967 following command@footnote{If your machine uses the systemd init system,
968 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
969 file in @file{/etc/systemd/system} will ensure that
970 @command{guix-daemon} is automatically started. Similarly, if your
971 machine uses the Upstart init system, drop the
972 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
973 file in @file{/etc/init}.}:
976 # guix-daemon --build-users-group=guixbuild
981 This way, the daemon starts build processes in a chroot, under one of
982 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
983 environment contains nothing but:
985 @c Keep this list in sync with libstore/build.cc! -----------------------
988 a minimal @code{/dev} directory, created mostly independently from the
989 host @code{/dev}@footnote{``Mostly'', because while the set of files
990 that appear in the chroot's @code{/dev} is fixed, most of these files
991 can only be created if the host has them.};
994 the @code{/proc} directory; it only shows the processes of the container
995 since a separate PID name space is used;
998 @file{/etc/passwd} with an entry for the current user and an entry for
1002 @file{/etc/group} with an entry for the user's group;
1005 @file{/etc/hosts} with an entry that maps @code{localhost} to
1009 a writable @file{/tmp} directory.
1012 You can influence the directory where the daemon stores build trees
1013 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1014 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1015 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1016 This way, the value of @env{TMPDIR} does not leak inside build
1017 environments, which avoids discrepancies in cases where build processes
1018 capture the name of their build tree.
1022 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1023 environment variables for HTTP and HTTPS downloads it performs, be it
1024 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1025 (@pxref{Substitutes}).
1027 If you are installing Guix as an unprivileged user, it is still possible
1028 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1029 However, build processes will not be isolated from one another, and not
1030 from the rest of the system. Thus, build processes may interfere with
1031 each other, and may access programs, libraries, and other files
1032 available on the system---making it much harder to view them as
1033 @emph{pure} functions.
1036 @node Daemon Offload Setup
1037 @subsection Using the Offload Facility
1041 When desired, the build daemon can @dfn{offload} derivation builds to
1042 other machines running Guix, using the @code{offload} @dfn{build
1043 hook}@footnote{This feature is available only when
1044 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1045 present.}. When that
1046 feature is enabled, a list of user-specified build machines is read from
1047 @file{/etc/guix/machines.scm}; every time a build is requested, for
1048 instance via @code{guix build}, the daemon attempts to offload it to one
1049 of the machines that satisfy the constraints of the derivation, in
1050 particular its system type---e.g., @file{x86_64-linux}. Missing
1051 prerequisites for the build are copied over SSH to the target machine,
1052 which then proceeds with the build; upon success the output(s) of the
1053 build are copied back to the initial machine.
1055 The @file{/etc/guix/machines.scm} file typically looks like this:
1058 (list (build-machine
1059 (name "eightysix.example.org")
1060 (system "x86_64-linux")
1061 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1063 (speed 2.)) ;incredibly fast!
1066 (name "armeight.example.org")
1067 (system "aarch64-linux")
1068 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1071 (string-append (getenv "HOME")
1072 "/.ssh/identity-for-guix"))))
1076 In the example above we specify a list of two build machines, one for
1077 the @code{x86_64} architecture and one for the @code{aarch64}
1080 In fact, this file is---not surprisingly!---a Scheme file that is
1081 evaluated when the @code{offload} hook is started. Its return value
1082 must be a list of @code{build-machine} objects. While this example
1083 shows a fixed list of build machines, one could imagine, say, using
1084 DNS-SD to return a list of potential build machines discovered in the
1085 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1086 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1089 @deftp {Data Type} build-machine
1090 This data type represents build machines to which the daemon may offload
1091 builds. The important fields are:
1096 The host name of the remote machine.
1099 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1102 The user account to use when connecting to the remote machine over SSH.
1103 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1104 allow non-interactive logins.
1107 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1108 This is used to authenticate the machine when we connect to it. It is a
1109 long string that looks like this:
1112 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1115 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1116 key can be found in a file such as
1117 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1119 If the machine is running the SSH daemon of GNU@tie{}lsh,
1120 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1121 similar file. It can be converted to the OpenSSH format using
1122 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1125 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1126 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1131 A number of optional fields may be specified:
1135 @item @code{port} (default: @code{22})
1136 Port number of SSH server on the machine.
1138 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1139 The SSH private key file to use when connecting to the machine, in
1140 OpenSSH format. This key must not be protected with a passphrase.
1142 Note that the default value is the private key @emph{of the root
1143 account}. Make sure it exists if you use the default.
1145 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1146 @itemx @code{compression-level} (default: @code{3})
1147 The SSH-level compression methods and compression level requested.
1149 Note that offloading relies on SSH compression to reduce bandwidth usage
1150 when transferring files to and from build machines.
1152 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1153 File name of the Unix-domain socket @command{guix-daemon} is listening
1156 @item @code{parallel-builds} (default: @code{1})
1157 The number of builds that may run in parallel on the machine.
1159 @item @code{speed} (default: @code{1.0})
1160 A ``relative speed factor''. The offload scheduler will tend to prefer
1161 machines with a higher speed factor.
1163 @item @code{features} (default: @code{'()})
1164 A list of strings denoting specific features supported by the machine.
1165 An example is @code{"kvm"} for machines that have the KVM Linux modules
1166 and corresponding hardware support. Derivations can request features by
1167 name, and they will be scheduled on matching build machines.
1172 The @command{guix} command must be in the search path on the build
1173 machines. You can check whether this is the case by running:
1176 ssh build-machine guix repl --version
1179 There is one last thing to do once @file{machines.scm} is in place. As
1180 explained above, when offloading, files are transferred back and forth
1181 between the machine stores. For this to work, you first need to
1182 generate a key pair on each machine to allow the daemon to export signed
1183 archives of files from the store (@pxref{Invoking guix archive}):
1186 # guix archive --generate-key
1190 Each build machine must authorize the key of the master machine so that
1191 it accepts store items it receives from the master:
1194 # guix archive --authorize < master-public-key.txt
1198 Likewise, the master machine must authorize the key of each build machine.
1200 All the fuss with keys is here to express pairwise mutual trust
1201 relations between the master and the build machines. Concretely, when
1202 the master receives files from a build machine (and @i{vice versa}), its
1203 build daemon can make sure they are genuine, have not been tampered
1204 with, and that they are signed by an authorized key.
1206 @cindex offload test
1207 To test whether your setup is operational, run this command on the
1214 This will attempt to connect to each of the build machines specified in
1215 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1216 available on each machine, attempt to export to the machine and import
1217 from it, and report any error in the process.
1219 If you want to test a different machine file, just specify it on the
1223 # guix offload test machines-qualif.scm
1226 Last, you can test the subset of the machines whose name matches a
1227 regular expression like this:
1230 # guix offload test machines.scm '\.gnu\.org$'
1233 @cindex offload status
1234 To display the current load of all build hosts, run this command on the
1238 # guix offload status
1242 @node SELinux Support
1243 @subsection SELinux Support
1245 @cindex SELinux, daemon policy
1246 @cindex mandatory access control, SELinux
1247 @cindex security, guix-daemon
1248 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1249 can be installed on a system where SELinux is enabled, in order to label
1250 Guix files and to specify the expected behavior of the daemon. Since
1251 Guix System does not provide an SELinux base policy, the daemon policy cannot
1252 be used on Guix System.
1254 @subsubsection Installing the SELinux policy
1255 @cindex SELinux, policy installation
1256 To install the policy run this command as root:
1259 semodule -i etc/guix-daemon.cil
1262 Then relabel the file system with @code{restorecon} or by a different
1263 mechanism provided by your system.
1265 Once the policy is installed, the file system has been relabeled, and
1266 the daemon has been restarted, it should be running in the
1267 @code{guix_daemon_t} context. You can confirm this with the following
1271 ps -Zax | grep guix-daemon
1274 Monitor the SELinux log files as you run a command like @code{guix build
1275 hello} to convince yourself that SELinux permits all necessary
1278 @subsubsection Limitations
1279 @cindex SELinux, limitations
1281 This policy is not perfect. Here is a list of limitations or quirks
1282 that should be considered when deploying the provided SELinux policy for
1287 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1288 operations involve contexts that have anything to do with
1289 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1290 but it would be preferrable to define socket rules for only this label.
1293 @code{guix gc} cannot access arbitrary links to profiles. By design,
1294 the file label of the destination of a symlink is independent of the
1295 file label of the link itself. Although all profiles under
1296 $localstatedir are labelled, the links to these profiles inherit the
1297 label of the directory they are in. For links in the user’s home
1298 directory this will be @code{user_home_t}. But for links from the root
1299 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1300 directory, etc, this won’t work. @code{guix gc} would be prevented from
1301 reading and following these links.
1304 The daemon’s feature to listen for TCP connections might no longer work.
1305 This might require extra rules, because SELinux treats network sockets
1306 differently from files.
1309 Currently all files with a name matching the regular expression
1310 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1311 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1312 that name in any profile would be permitted to run in the
1313 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1314 build a package that provides this executable and convince a user to
1315 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1316 At that point SELinux could not prevent it from accessing files that are
1317 allowed for processes in that domain.
1319 We could generate a much more restrictive policy at installation time,
1320 so that only the @emph{exact} file name of the currently installed
1321 @code{guix-daemon} executable would be labelled with
1322 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1323 The downside is that root would have to install or upgrade the policy at
1324 installation time whenever the Guix package that provides the
1325 effectively running @code{guix-daemon} executable is upgraded.
1328 @node Invoking guix-daemon
1329 @section Invoking @command{guix-daemon}
1331 The @command{guix-daemon} program implements all the functionality to
1332 access the store. This includes launching build processes, running the
1333 garbage collector, querying the availability of a build result, etc. It
1334 is normally run as @code{root} like this:
1337 # guix-daemon --build-users-group=guixbuild
1341 For details on how to set it up, @pxref{Setting Up the Daemon}.
1344 @cindex container, build environment
1345 @cindex build environment
1346 @cindex reproducible builds
1347 By default, @command{guix-daemon} launches build processes under
1348 different UIDs, taken from the build group specified with
1349 @option{--build-users-group}. In addition, each build process is run in a
1350 chroot environment that only contains the subset of the store that the
1351 build process depends on, as specified by its derivation
1352 (@pxref{Programming Interface, derivation}), plus a set of specific
1353 system directories. By default, the latter contains @file{/dev} and
1354 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1355 @dfn{container}: in addition to having its own file system tree, it has
1356 a separate mount name space, its own PID name space, network name space,
1357 etc. This helps achieve reproducible builds (@pxref{Features}).
1359 When the daemon performs a build on behalf of the user, it creates a
1360 build directory under @file{/tmp} or under the directory specified by
1361 its @env{TMPDIR} environment variable. This directory is shared with
1362 the container for the duration of the build, though within the container,
1363 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1365 The build directory is automatically deleted upon completion, unless the
1366 build failed and the client specified @option{--keep-failed}
1367 (@pxref{Invoking guix build, @option{--keep-failed}}).
1369 The daemon listens for connections and spawns one sub-process for each session
1370 started by a client (one of the @command{guix} sub-commands). The
1371 @command{guix processes} command allows you to get an overview of the activity
1372 on your system by viewing each of the active sessions and clients.
1373 @xref{Invoking guix processes}, for more information.
1375 The following command-line options are supported:
1378 @item --build-users-group=@var{group}
1379 Take users from @var{group} to run build processes (@pxref{Setting Up
1380 the Daemon, build users}).
1382 @item --no-substitutes
1384 Do not use substitutes for build products. That is, always build things
1385 locally instead of allowing downloads of pre-built binaries
1386 (@pxref{Substitutes}).
1388 When the daemon runs with @option{--no-substitutes}, clients can still
1389 explicitly enable substitution @i{via} the @code{set-build-options}
1390 remote procedure call (@pxref{The Store}).
1392 @item --substitute-urls=@var{urls}
1393 @anchor{daemon-substitute-urls}
1394 Consider @var{urls} the default whitespace-separated list of substitute
1395 source URLs. When this option is omitted,
1396 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1398 This means that substitutes may be downloaded from @var{urls}, as long
1399 as they are signed by a trusted signature (@pxref{Substitutes}).
1403 Do not use offload builds to other machines (@pxref{Daemon Offload
1404 Setup}). That is, always build things locally instead of offloading
1405 builds to remote machines.
1407 @item --cache-failures
1408 Cache build failures. By default, only successful builds are cached.
1410 When this option is used, @command{guix gc --list-failures} can be used
1411 to query the set of store items marked as failed; @command{guix gc
1412 --clear-failures} removes store items from the set of cached failures.
1413 @xref{Invoking guix gc}.
1415 @item --cores=@var{n}
1417 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1420 The default value is @code{0}, but it may be overridden by clients, such
1421 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1424 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1425 in the build process, which can then use it to exploit internal
1426 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1428 @item --max-jobs=@var{n}
1430 Allow at most @var{n} build jobs in parallel. The default value is
1431 @code{1}. Setting it to @code{0} means that no builds will be performed
1432 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1433 Setup}), or simply fail.
1435 @item --max-silent-time=@var{seconds}
1436 When the build or substitution process remains silent for more than
1437 @var{seconds}, terminate it and report a build failure.
1439 The default value is @code{0}, which disables the timeout.
1441 The value specified here can be overridden by clients (@pxref{Common
1442 Build Options, @option{--max-silent-time}}).
1444 @item --timeout=@var{seconds}
1445 Likewise, when the build or substitution process lasts for more than
1446 @var{seconds}, terminate it and report a build failure.
1448 The default value is @code{0}, which disables the timeout.
1450 The value specified here can be overridden by clients (@pxref{Common
1451 Build Options, @option{--timeout}}).
1453 @item --rounds=@var{N}
1454 Build each derivation @var{n} times in a row, and raise an error if
1455 consecutive build results are not bit-for-bit identical. Note that this
1456 setting can be overridden by clients such as @command{guix build}
1457 (@pxref{Invoking guix build}).
1459 When used in conjunction with @option{--keep-failed}, the differing
1460 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1461 This makes it easy to look for differences between the two results.
1464 Produce debugging output.
1466 This is useful to debug daemon start-up issues, but then it may be
1467 overridden by clients, for example the @option{--verbosity} option of
1468 @command{guix build} (@pxref{Invoking guix build}).
1470 @item --chroot-directory=@var{dir}
1471 Add @var{dir} to the build chroot.
1473 Doing this may change the result of build processes---for instance if
1474 they use optional dependencies found in @var{dir} when it is available,
1475 and not otherwise. For that reason, it is not recommended to do so.
1476 Instead, make sure that each derivation declares all the inputs that it
1479 @item --disable-chroot
1480 Disable chroot builds.
1482 Using this option is not recommended since, again, it would allow build
1483 processes to gain access to undeclared dependencies. It is necessary,
1484 though, when @command{guix-daemon} is running under an unprivileged user
1487 @item --log-compression=@var{type}
1488 Compress build logs according to @var{type}, one of @code{gzip},
1489 @code{bzip2}, or @code{none}.
1491 Unless @option{--lose-logs} is used, all the build logs are kept in the
1492 @var{localstatedir}. To save space, the daemon automatically compresses
1493 them with Bzip2 by default.
1495 @item --disable-deduplication
1496 @cindex deduplication
1497 Disable automatic file ``deduplication'' in the store.
1499 By default, files added to the store are automatically ``deduplicated'':
1500 if a newly added file is identical to another one found in the store,
1501 the daemon makes the new file a hard link to the other file. This can
1502 noticeably reduce disk usage, at the expense of slightly increased
1503 input/output load at the end of a build process. This option disables
1506 @item --gc-keep-outputs[=yes|no]
1507 Tell whether the garbage collector (GC) must keep outputs of live
1511 @cindex garbage collector roots
1512 When set to @code{yes}, the GC will keep the outputs of any live
1513 derivation available in the store---the @file{.drv} files. The default
1514 is @code{no}, meaning that derivation outputs are kept only if they are
1515 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1518 @item --gc-keep-derivations[=yes|no]
1519 Tell whether the garbage collector (GC) must keep derivations
1520 corresponding to live outputs.
1522 When set to @code{yes}, as is the case by default, the GC keeps
1523 derivations---i.e., @file{.drv} files---as long as at least one of their
1524 outputs is live. This allows users to keep track of the origins of
1525 items in their store. Setting it to @code{no} saves a bit of disk
1528 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1529 liveness to flow from outputs to derivations, and setting
1530 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1531 derivations to outputs. When both are set to @code{yes}, the effect is
1532 to keep all the build prerequisites (the sources, compiler, libraries,
1533 and other build-time tools) of live objects in the store, regardless of
1534 whether these prerequisites are reachable from a GC root. This is
1535 convenient for developers since it saves rebuilds or downloads.
1537 @item --impersonate-linux-2.6
1538 On Linux-based systems, impersonate Linux 2.6. This means that the
1539 kernel's @command{uname} system call will report 2.6 as the release number.
1541 This might be helpful to build programs that (usually wrongfully) depend
1542 on the kernel version number.
1545 Do not keep build logs. By default they are kept under
1546 @file{@var{localstatedir}/guix/log}.
1548 @item --system=@var{system}
1549 Assume @var{system} as the current system type. By default it is the
1550 architecture/kernel pair found at configure time, such as
1551 @code{x86_64-linux}.
1553 @item --listen=@var{endpoint}
1554 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1555 as the file name of a Unix-domain socket if it starts with
1556 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1557 host name or host name and port to listen to. Here are a few examples:
1560 @item --listen=/gnu/var/daemon
1561 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1562 creating it if needed.
1564 @item --listen=localhost
1565 @cindex daemon, remote access
1566 @cindex remote access to the daemon
1567 @cindex daemon, cluster setup
1568 @cindex clusters, daemon setup
1569 Listen for TCP connections on the network interface corresponding to
1570 @code{localhost}, on port 44146.
1572 @item --listen=128.0.0.42:1234
1573 Listen for TCP connections on the network interface corresponding to
1574 @code{128.0.0.42}, on port 1234.
1577 This option can be repeated multiple times, in which case
1578 @command{guix-daemon} accepts connections on all the specified
1579 endpoints. Users can tell client commands what endpoint to connect to
1580 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1581 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1584 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1585 @option{--listen=@var{host}} is suitable on local networks, such as
1586 clusters, where only trusted nodes may connect to the build daemon. In
1587 other cases where remote access to the daemon is needed, we recommend
1588 using Unix-domain sockets along with SSH.
1591 When @option{--listen} is omitted, @command{guix-daemon} listens for
1592 connections on the Unix-domain socket located at
1593 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1597 @node Application Setup
1598 @section Application Setup
1600 @cindex foreign distro
1601 When using Guix on top of GNU/Linux distribution other than Guix System---a
1602 so-called @dfn{foreign distro}---a few additional steps are needed to
1603 get everything in place. Here are some of them.
1607 @anchor{locales-and-locpath}
1608 @cindex locales, when not on Guix System
1610 @vindex GUIX_LOCPATH
1611 Packages installed @i{via} Guix will not use the locale data of the
1612 host system. Instead, you must first install one of the locale packages
1613 available with Guix and then define the @env{GUIX_LOCPATH} environment
1617 $ guix install glibc-locales
1618 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1621 Note that the @code{glibc-locales} package contains data for all the
1622 locales supported by the GNU@tie{}libc and weighs in at around
1623 917@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1624 limited to a few UTF-8 locales.
1626 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1627 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1628 Manual}). There are two important differences though:
1632 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1633 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1634 to make sure the programs of the foreign distro will not end up loading
1635 incompatible locale data.
1638 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1639 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1640 should your Guix profile contain a mixture of programs linked against
1641 different libc version, each libc version will only try to load locale
1642 data in the right format.
1645 This is important because the locale data format used by different libc
1646 versions may be incompatible.
1648 @subsection Name Service Switch
1650 @cindex name service switch, glibc
1651 @cindex NSS (name service switch), glibc
1652 @cindex nscd (name service caching daemon)
1653 @cindex name service caching daemon (nscd)
1654 When using Guix on a foreign distro, we @emph{strongly recommend} that
1655 the system run the GNU C library's @dfn{name service cache daemon},
1656 @command{nscd}, which should be listening on the
1657 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1658 installed with Guix may fail to look up host names or user accounts, or
1659 may even crash. The next paragraphs explain why.
1661 @cindex @file{nsswitch.conf}
1662 The GNU C library implements a @dfn{name service switch} (NSS), which is
1663 an extensible mechanism for ``name lookups'' in general: host name
1664 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1665 The GNU C Library Reference Manual}).
1667 @cindex Network information service (NIS)
1668 @cindex NIS (Network information service)
1669 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1670 lookup implementations: for example, the @code{nss-mdns} plugin allow
1671 resolution of @code{.local} host names, the @code{nis} plugin allows
1672 user account lookup using the Network information service (NIS), and so
1673 on. These extra ``lookup services'' are configured system-wide in
1674 @file{/etc/nsswitch.conf}, and all the programs running on the system
1675 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1678 When they perform a name lookup---for instance by calling the
1679 @code{getaddrinfo} function in C---applications first try to connect to
1680 the nscd; on success, nscd performs name lookups on their behalf. If
1681 the nscd is not running, then they perform the name lookup by
1682 themselves, by loading the name lookup services into their own address
1683 space and running it. These name lookup services---the
1684 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1685 the host system's C library, rather than from the C library the
1686 application is linked against (the C library coming from Guix).
1688 And this is where the problem is: if your application is linked against
1689 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1690 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1691 likely crash or have its name lookups fail unexpectedly.
1693 Running @command{nscd} on the system, among other advantages, eliminates
1694 this binary incompatibility problem because those @code{libnss_*.so}
1695 files are loaded in the @command{nscd} process, not in applications
1698 @subsection X11 Fonts
1701 The majority of graphical applications use Fontconfig to locate and
1702 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1703 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1704 by default. Thus, to allow graphical applications installed with Guix
1705 to display fonts, you have to install fonts with Guix as well.
1706 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1707 @code{font-gnu-freefont}.
1709 @cindex @code{fc-cache}
1711 Once you have installed or removed fonts, or when you notice an
1712 application that does not find fonts, you may need to install Fontconfig
1713 and to force an update of its font cache by running:
1716 guix install fontconfig
1720 To display text written in Chinese languages, Japanese, or Korean in
1721 graphical applications, consider installing
1722 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1723 has multiple outputs, one per language family (@pxref{Packages with
1724 Multiple Outputs}). For instance, the following command installs fonts
1725 for Chinese languages:
1728 guix install font-adobe-source-han-sans:cn
1731 @cindex @code{xterm}
1732 Older programs such as @command{xterm} do not use Fontconfig and instead
1733 rely on server-side font rendering. Such programs require to specify a
1734 full name of a font using XLFD (X Logical Font Description), like this:
1737 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1740 To be able to use such full names for the TrueType fonts installed in
1741 your Guix profile, you need to extend the font path of the X server:
1743 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1744 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1746 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1749 @cindex @code{xlsfonts}
1750 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1751 to make sure your TrueType fonts are listed there.
1754 @subsection X.509 Certificates
1756 @cindex @code{nss-certs}
1757 The @code{nss-certs} package provides X.509 certificates, which allow
1758 programs to authenticate Web servers accessed over HTTPS.
1760 When using Guix on a foreign distro, you can install this package and
1761 define the relevant environment variables so that packages know where to
1762 look for certificates. @xref{X.509 Certificates}, for detailed
1765 @subsection Emacs Packages
1767 @cindex @code{emacs}
1768 When you install Emacs packages with Guix, the Elisp files are placed
1769 under the @file{share/emacs/site-lisp/} directory of the profile in
1770 which they are installed. The Elisp libraries are made available to
1771 Emacs through the @env{EMACSLOADPATH} environment variable, which is
1772 set when installing Emacs itself.
1774 Additionally, autoload definitions are automatically evaluated at the
1775 initialization of Emacs, by the Guix-specific
1776 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
1777 want to avoid auto-loading the Emacs packages installed with Guix, you
1778 can do so by running Emacs with the @option{--no-site-file} option
1779 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1782 @node Upgrading Guix
1783 @section Upgrading Guix
1785 @cindex Upgrading Guix, on a foreign distro
1787 To upgrade Guix, run:
1793 @xref{Invoking guix pull}, for more information.
1795 @cindex upgrading Guix for the root user, on a foreign distro
1796 @cindex upgrading the Guix daemon, on a foreign distro
1797 @cindex @command{guix pull} for the root user, on a foreign distro
1799 On a foreign distro, you can upgrade the build daemon by running:
1806 followed by (assuming your distro uses the systemd service management
1810 systemctl restart guix-daemon.service
1813 On Guix System, upgrading the daemon is achieved by reconfiguring the
1814 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
1818 @c *********************************************************************
1819 @node System Installation
1820 @chapter System Installation
1822 @cindex installing Guix System
1823 @cindex Guix System, installation
1824 This section explains how to install Guix System
1825 on a machine. Guix, as a package manager, can
1826 also be installed on top of a running GNU/Linux system,
1827 @pxref{Installation}.
1831 @c This paragraph is for people reading this from tty2 of the
1832 @c installation image.
1833 You are reading this documentation with an Info reader. For details on
1834 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1835 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1836 Info}. Hit @kbd{l} afterwards to come back here.
1838 Alternatively, run @command{info info} in another tty to keep the manual
1844 * Limitations:: What you can expect.
1845 * Hardware Considerations:: Supported hardware.
1846 * USB Stick and DVD Installation:: Preparing the installation medium.
1847 * Preparing for Installation:: Networking, partitioning, etc.
1848 * Guided Graphical Installation:: Easy graphical installation.
1849 * Manual Installation:: Manual installation for wizards.
1850 * After System Installation:: When installation succeeded.
1851 * Installing Guix in a VM:: Guix System playground.
1852 * Building the Installation Image:: How this comes to be.
1856 @section Limitations
1858 We consider Guix System to be ready for a wide range of ``desktop'' and server
1859 use cases. The reliability guarantees it provides---transactional upgrades
1860 and rollbacks, reproducibility---make it a solid foundation.
1862 Nevertheless, before you proceed with the installation, be aware of the
1863 following noteworthy limitations applicable to version @value{VERSION}:
1867 Support for the Logical Volume Manager (LVM) is missing.
1870 More and more system services are provided (@pxref{Services}), but some
1874 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1875 as well as a number of X11 window managers. However, KDE is currently
1879 More than a disclaimer, this is an invitation to report issues (and success
1880 stories!), and to join us in improving it. @xref{Contributing}, for more
1884 @node Hardware Considerations
1885 @section Hardware Considerations
1887 @cindex hardware support on Guix System
1888 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1889 builds around the kernel Linux-libre, which means that only hardware for
1890 which free software drivers and firmware exist is supported. Nowadays,
1891 a wide range of off-the-shelf hardware is supported on
1892 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1893 Ethernet controllers. Unfortunately, there are still areas where
1894 hardware vendors deny users control over their own computing, and such
1895 hardware is not supported on Guix System.
1897 @cindex WiFi, hardware support
1898 One of the main areas where free drivers or firmware are lacking is WiFi
1899 devices. WiFi devices known to work include those using Atheros chips
1900 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1901 driver, and those using Broadcom/AirForce chips (BCM43xx with
1902 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1903 Linux-libre driver. Free firmware exists for both and is available
1904 out-of-the-box on Guix System, as part of @code{%base-firmware}
1905 (@pxref{operating-system Reference, @code{firmware}}).
1907 @cindex RYF, Respects Your Freedom
1908 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1909 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1910 certification program for hardware products that respect your freedom
1911 and your privacy and ensure that you have control over your device. We
1912 encourage you to check the list of RYF-certified devices.
1914 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1915 web site. It contains a catalog of hardware devices with information
1916 about their support in GNU/Linux.
1919 @node USB Stick and DVD Installation
1920 @section USB Stick and DVD Installation
1922 An ISO-9660 installation image that can be written to a USB stick or
1923 burnt to a DVD can be downloaded from
1924 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz},
1925 where you can replace @code{x86_64-linux} with one of:
1929 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1932 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1935 @c start duplication of authentication part from ``Binary Installation''
1936 Make sure to download the associated @file{.sig} file and to verify the
1937 authenticity of the image against it, along these lines:
1940 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
1941 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
1944 If that command fails because you do not have the required public key,
1945 then run this command to import it:
1948 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
1949 -qO - | gpg --import -
1953 and rerun the @code{gpg --verify} command.
1955 Take note that a warning like ``This key is not certified with a trusted
1956 signature!'' is normal.
1960 This image contains the tools necessary for an installation.
1961 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1963 @unnumberedsubsec Copying to a USB Stick
1965 To copy the image to a USB stick, follow these steps:
1969 Decompress the image using the @command{xz} command:
1972 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
1976 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1977 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1978 copy the image with:
1981 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX 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 @cindex authentication, of channel code
3985 The @command{guix pull} and @command{guix time-machine} commands
3986 @dfn{authenticate} the code retrieved from channels: they make sure each
3987 commit that is fetched is signed by an authorized developer. The goal
3988 is to protect from unauthorized modifications to the channel that would
3989 lead users to run malicious code.
3991 As a user, you must provide a @dfn{channel introduction} in your
3992 channels file so that Guix knows how to authenticate its first commit.
3993 A channel specification, including its introduction, looks something
3999 (url "https://example.org/my-channel.git")
4001 (make-channel-introduction
4002 "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
4003 (openpgp-fingerprint
4004 "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
4007 The specification above shows the name and URL of the channel. The call
4008 to @code{make-channel-introduction} above specifies that authentication
4009 of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
4010 by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
4012 For the main channel, called @code{guix}, you automatically get that
4013 information from your Guix installation. For other channels, include
4014 the channel introduction provided by the channel authors in your
4015 @file{channels.scm} file. Make sure you retrieve the channel
4016 introduction from a trusted source since that is the root of your trust.
4018 If you're curious about the authentication mechanics, read on!
4020 @subsection Using a Custom Guix Channel
4022 The channel called @code{guix} specifies where Guix itself---its command-line
4023 tools as well as its package collection---should be downloaded. For instance,
4024 suppose you want to update from your own copy of the Guix repository at
4025 @code{example.org}, and specifically the @code{super-hacks} branch, you can
4026 write in @code{~/.config/guix/channels.scm} this specification:
4029 ;; Tell 'guix pull' to use my own repo.
4032 (url "https://example.org/my-guix.git")
4033 (branch "super-hacks")))
4037 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
4038 branch of the repository at @code{example.org}.
4040 @subsection Specifying Additional Channels
4042 @cindex extending the package collection (channels)
4043 @cindex personal packages (channels)
4044 @cindex channels, for personal packages
4045 You can also specify @emph{additional channels} to pull from. Let's say you
4046 have a bunch of custom package variants or personal packages that you think
4047 would make little sense to contribute to the Guix project, but would like to
4048 have these packages transparently available to you at the command line. You
4049 would first write modules containing those package definitions (@pxref{Package
4050 Modules}), maintain them in a Git repository, and then you and anyone else can
4051 use it as an additional channel to get packages from. Neat, no?
4053 @c What follows stems from discussions at
4054 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
4055 @c earlier discussions on guix-devel@gnu.org.
4057 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
4058 publish your personal channel to the world, we would like to share a few words
4063 Before publishing a channel, please consider contributing your package
4064 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
4065 to free software of all sorts, and packages in Guix proper are readily
4066 available to all Guix users and benefit from the project's quality assurance
4070 When you maintain package definitions outside Guix, we, Guix developers,
4071 consider that @emph{the compatibility burden is on you}. Remember that
4072 package modules and package definitions are just Scheme code that uses various
4073 programming interfaces (APIs). We want to remain free to change these APIs to
4074 keep improving Guix, possibly in ways that break your channel. We never
4075 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
4079 Corollary: if you're using an external channel and that channel breaks, please
4080 @emph{report the issue to the channel authors}, not to the Guix project.
4083 You've been warned! Having said this, we believe external channels are a
4084 practical way to exert your freedom to augment Guix' package collection and to
4085 share your improvements, which are basic tenets of
4086 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
4087 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
4090 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
4091 @command{guix pull} to pull from it @emph{in addition} to the default Guix
4094 @vindex %default-channels
4096 ;; Add my personal packages to those Guix provides.
4098 (name 'my-personal-packages)
4099 (url "https://example.org/personal-packages.git"))
4104 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
4105 add a channel the list of channels that the variable @code{%default-channels}
4106 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
4107 Manual}). With this file in place, @command{guix pull} builds not only Guix
4108 but also the package modules from your own repository. The result in
4109 @file{~/.config/guix/current} is the union of Guix with your own package
4113 $ guix pull --list-generations
4115 Generation 19 Aug 27 2018 16:20:48
4117 repository URL: https://git.savannah.gnu.org/git/guix.git
4119 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
4120 my-personal-packages dd3df5e
4121 repository URL: https://example.org/personal-packages.git
4123 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
4124 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
4125 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
4129 The output of @command{guix pull} above shows that Generation@tie{}19 includes
4130 both Guix and packages from the @code{my-personal-packages} channel. Among
4131 the new and upgraded packages that are listed, some like @code{my-gimp} and
4132 @code{my-emacs-with-cool-features} might come from
4133 @code{my-personal-packages}, while others come from the Guix default channel.
4135 To create a channel, create a Git repository containing your own package
4136 modules and make it available. The repository can contain anything, but a
4137 useful channel will contain Guile modules that export packages. Once you
4138 start using a channel, Guix will behave as if the root directory of that
4139 channel's Git repository has been added to the Guile load path (@pxref{Load
4140 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
4141 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
4142 module, then the module will be available under the name @code{(my-packages
4143 my-tools)}, and you will be able to use it like any other module
4144 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
4146 @cindex dependencies, channels
4147 @cindex meta-data, channels
4148 @subsection Declaring Channel Dependencies
4150 Channel authors may decide to augment a package collection provided by other
4151 channels. They can declare their channel to be dependent on other channels in
4152 a meta-data file @file{.guix-channel}, which is to be placed in the root of
4153 the channel repository.
4155 The meta-data file should contain a simple S-expression like this:
4162 (name some-collection)
4163 (url "https://example.org/first-collection.git")
4165 ;; The 'introduction' bit below is optional: you would
4166 ;; provide it for dependencies that can be authenticated.
4168 (channel-introduction
4170 (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
4171 (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
4173 (name some-other-collection)
4174 (url "https://example.org/second-collection.git")
4175 (branch "testing"))))
4178 In the above example this channel is declared to depend on two other channels,
4179 which will both be fetched automatically. The modules provided by the channel
4180 will be compiled in an environment where the modules of all these declared
4181 channels are available.
4183 For the sake of reliability and maintainability, you should avoid dependencies
4184 on channels that you don't control, and you should aim to keep the number of
4185 dependencies to a minimum.
4187 @cindex subdirectory, channels
4188 @subsection Package Modules in a Sub-directory
4190 As a channel author, you may want to keep your channel modules in a
4191 sub-directory. If your modules are in the sub-directory @file{guix}, you must
4192 add a meta-data file @file{.guix-channel} that contains:
4200 @cindex channel authorizations
4201 @subsection Specifying Channel Authorizations
4203 As we saw above, Guix ensures the source code it pulls from channels
4204 comes from authorized developers. As a channel author, you need to
4205 specify the list of authorized developers in the
4206 @file{.guix-authorizations} file in the channel's Git repository. The
4207 authentication rule is simple: each commit must be signed by a key
4208 listed in the @file{.guix-authorizations} file of its parent
4209 commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
4210 (DAG). Each commit can have zero or more parents; ``regular'' commits
4211 have one parent and merge commits have two parent commits. Read
4212 @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
4213 for Computer Scientists}} for a great overview.} The
4214 @file{.guix-authorizations} file looks like this:
4217 ;; Example '.guix-authorizations' file.
4220 (version 0) ;current file format version
4222 (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
4224 ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
4226 ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
4230 Each fingerprint is followed by optional key/value pairs, as in the
4231 example above. Currently these key/value pairs are ignored.
4233 This authentication rule creates a chicken-and-egg issue: how do we
4234 authenticate the first commit? Related to that: how do we deal with
4235 channels whose repository history contains unsigned commits and lack
4236 @file{.guix-authorizations}? And how do we fork existing channels?
4238 @cindex channel introduction
4239 Channel introductions answer these questions by describing the first
4240 commit of a channel that should be authenticated. The first time a
4241 channel is fetched with @command{guix pull} or @command{guix
4242 time-machine}, the command looks up the introductory commit and verifies
4243 that it is signed by the specified OpenPGP key. From then on, it
4244 authenticates commits according to the rule above.
4246 To summarize, as the author of a channel, there are two things you have
4247 to do to allow users to authenticate your code:
4251 Introduce an initial @file{.guix-authorizations} in the channel's
4252 repository. Do that in a signed commit (@pxref{Commit Access}, for
4253 information on how to sign Git commits.)
4256 Advertise the channel introduction, for instance on your channel's web
4257 page. The channel introduction, as we saw above, is the commit/key
4258 pair---i.e., the commit that introduced @file{.guix-authorizations}, and
4259 the fingerprint of the OpenPGP used to sign it.
4262 Publishing a signed channel requires discipline: any mistake, such as an
4263 unsigned commit or a commit signed by an unauthorized key, will prevent
4264 users from pulling from your channel---well, that's the whole point of
4265 authentication! Pay attention to merges in particular: merge commits
4266 are considered authentic if and only if they are signed by a key present
4267 in the @file{.guix-authorizations} file of @emph{both} branches.
4269 @cindex primary URL, channels
4270 @subsection Primary URL
4272 Channel authors can indicate the primary URL of their channel's Git
4273 repository in the @file{.guix-channel} file, like so:
4278 (url "https://example.org/guix.git"))
4281 This allows @command{guix pull} to determine whether it is pulling code
4282 from a mirror of the channel; when that is the case, it warns the user
4283 that the mirror might be stale and displays the primary URL. That way,
4284 users cannot be tricked into fetching code from a stale mirror that does
4285 not receive security updates.
4287 This feature only makes sense for authenticated repositories, such as
4288 the official @code{guix} channel, for which @command{guix pull} ensures
4289 the code it fetches is authentic.
4291 @cindex news, for channels
4292 @subsection Writing Channel News
4294 Channel authors may occasionally want to communicate to their users
4295 information about important changes in the channel. You'd send them all
4296 an email, but that's not convenient.
4298 Instead, channels can provide a @dfn{news file}; when the channel users
4299 run @command{guix pull}, that news file is automatically read and
4300 @command{guix pull --news} can display the announcements that correspond
4301 to the new commits that have been pulled, if any.
4303 To do that, channel authors must first declare the name of the news file
4304 in their @file{.guix-channel} file:
4309 (news-file "etc/news.txt"))
4312 The news file itself, @file{etc/news.txt} in this example, must look
4313 something like this:
4318 (entry (tag "the-bug-fix")
4319 (title (en "Fixed terrible bug")
4321 (body (en "@@emph@{Good news@}! It's fixed!")
4322 (eo "Certe ĝi pli bone funkcias nun!")))
4323 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
4324 (title (en "Added a great package")
4325 (ca "Què vol dir guix?"))
4326 (body (en "Don't miss the @@code@{hello@} package!"))))
4329 The file consists of a list of @dfn{news entries}. Each entry is
4330 associated with a commit or tag: it describes changes made in this
4331 commit, possibly in preceding commits as well. Users see entries only
4332 the first time they obtain the commit the entry refers to.
4334 The @code{title} field should be a one-line summary while @code{body}
4335 can be arbitrarily long, and both can contain Texinfo markup
4336 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
4337 a list of language tag/message tuples, which allows @command{guix pull}
4338 to display news in the language that corresponds to the user's locale.
4340 If you want to translate news using a gettext-based workflow, you can
4341 extract translatable strings with @command{xgettext} (@pxref{xgettext
4342 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
4343 you write news entries in English first, the command below creates a PO
4344 file containing the strings to translate:
4347 xgettext -o news.po -l scheme -ken etc/news.scm
4350 To sum up, yes, you could use your channel as a blog. But beware, this
4351 is @emph{not quite} what your users might expect.
4353 @subsection Replicating Guix
4355 @cindex pinning, channels
4356 @cindex replicating Guix
4357 @cindex reproducibility, of Guix
4358 The @command{guix pull --list-generations} output above shows precisely which
4359 commits were used to build this instance of Guix. We can thus replicate it,
4360 say, on another machine, by providing a channel specification in
4361 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
4364 ;; Deploy specific commits of my channels of interest.
4367 (url "https://git.savannah.gnu.org/git/guix.git")
4368 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
4370 (name 'my-personal-packages)
4371 (url "https://example.org/personal-packages.git")
4372 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
4375 The @command{guix describe --format=channels} command can even generate this
4376 list of channels directly (@pxref{Invoking guix describe}). The resulting
4377 file can be used with the -C options of @command{guix pull}
4378 (@pxref{Invoking guix pull}) or @command{guix time-machine}
4379 (@pxref{Invoking guix time-machine}).
4381 At this point the two machines run the @emph{exact same Guix}, with access to
4382 the @emph{exact same packages}. The output of @command{guix build gimp} on
4383 one machine will be exactly the same, bit for bit, as the output of the same
4384 command on the other machine. It also means both machines have access to all
4385 the source code of Guix and, transitively, to all the source code of every
4388 This gives you super powers, allowing you to track the provenance of binary
4389 artifacts with very fine grain, and to reproduce software environments at
4390 will---some sort of ``meta reproducibility'' capabilities, if you will.
4391 @xref{Inferiors}, for another way to take advantage of these super powers.
4393 @node Invoking guix time-machine
4394 @section Invoking @command{guix time-machine}
4396 @cindex @command{guix time-machine}
4397 @cindex pinning, channels
4398 @cindex replicating Guix
4399 @cindex reproducibility, of Guix
4401 The @command{guix time-machine} command provides access to other
4402 revisions of Guix, for example to install older versions of packages,
4403 or to reproduce a computation in an identical environment. The revision
4404 of Guix to be used is defined by a commit or by a channel
4405 description file created by @command{guix describe}
4406 (@pxref{Invoking guix describe}).
4408 The general syntax is:
4411 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4414 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4415 @command{guix} command of the specified revision. The @var{options} that define
4416 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4419 @item --url=@var{url}
4420 @itemx --commit=@var{commit}
4421 @itemx --branch=@var{branch}
4422 Use the @code{guix} channel from the specified @var{url}, at the
4423 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4424 string), or @var{branch}.
4426 @item --channels=@var{file}
4427 @itemx -C @var{file}
4428 Read the list of channels from @var{file}. @var{file} must contain
4429 Scheme code that evaluates to a list of channel objects.
4430 @xref{Channels} for more information.
4433 As for @command{guix pull}, the absence of any options means that the
4434 the latest commit on the master branch will be used. The command
4437 guix time-machine -- build hello
4440 will thus build the package @code{hello} as defined in the master branch,
4441 which is in general a newer revision of Guix than you have installed.
4442 Time travel works in both directions!
4444 Note that @command{guix time-machine} can trigger builds of channels and
4445 their dependencies, and these are controlled by the standard build
4446 options (@pxref{Common Build Options}).
4451 @c TODO: Remove this once we're more confident about API stability.
4453 The functionality described here is a ``technology preview'' as of version
4454 @value{VERSION}. As such, the interface is subject to change.
4458 @cindex composition of Guix revisions
4459 Sometimes you might need to mix packages from the revision of Guix you're
4460 currently running with packages available in a different revision of Guix.
4461 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4462 revisions in arbitrary ways.
4464 @cindex inferior packages
4465 Technically, an ``inferior'' is essentially a separate Guix process connected
4466 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4467 @code{(guix inferior)} module allows you to create inferiors and to
4468 communicate with them. It also provides a high-level interface to browse and
4469 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4471 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4472 to interact with a separate revision of Guix. For example, let's assume you
4473 want to install in your profile the current @code{guile} package, along with
4474 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4475 because the newer @code{guile-json} has an incompatible API and you want to
4476 run your code against the old API@. To do that, you could write a manifest for
4477 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4478 manifest, you would create an inferior for that old Guix revision you care
4479 about, and you would look up the @code{guile-json} package in the inferior:
4482 (use-modules (guix inferior) (guix channels)
4483 (srfi srfi-1)) ;for 'first'
4486 ;; This is the old revision from which we want to
4487 ;; extract guile-json.
4490 (url "https://git.savannah.gnu.org/git/guix.git")
4492 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4495 ;; An inferior representing the above revision.
4496 (inferior-for-channels channels))
4498 ;; Now create a manifest with the current "guile" package
4499 ;; and the old "guile-json" package.
4501 (list (first (lookup-inferior-packages inferior "guile-json"))
4502 (specification->package "guile")))
4505 On its first run, @command{guix package --manifest} might have to build the
4506 channel you specified before it can create the inferior; subsequent runs will
4507 be much faster because the Guix revision will be cached.
4509 The @code{(guix inferior)} module provides the following procedures to open an
4512 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4513 [#:cache-directory] [#:ttl]
4514 Return an inferior for @var{channels}, a list of channels. Use the cache at
4515 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4516 This procedure opens a new connection to the build daemon.
4518 As a side effect, this procedure may build or substitute binaries for
4519 @var{channels}, which can take time.
4522 @deffn {Scheme Procedure} open-inferior @var{directory} @
4523 [#:command "bin/guix"]
4524 Open the inferior Guix in @var{directory}, running
4525 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4526 the inferior could not be launched.
4529 @cindex inferior packages
4530 The procedures listed below allow you to obtain and manipulate inferior
4533 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4534 Return the list of packages known to @var{inferior}.
4537 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4539 Return the sorted list of inferior packages matching @var{name} in
4540 @var{inferior}, with highest version numbers first. If @var{version} is true,
4541 return only packages with a version number prefixed by @var{version}.
4544 @deffn {Scheme Procedure} inferior-package? @var{obj}
4545 Return true if @var{obj} is an inferior package.
4548 @deffn {Scheme Procedure} inferior-package-name @var{package}
4549 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4550 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4551 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4552 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4553 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4554 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4555 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4556 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4557 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4558 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4559 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4560 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4561 These procedures are the counterpart of package record accessors
4562 (@pxref{package Reference}). Most of them work by querying the inferior
4563 @var{package} comes from, so the inferior must still be live when you call
4567 Inferior packages can be used transparently like any other package or
4568 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4569 transparently handled by the @code{packages->manifest} procedure, which is
4570 commonly use in manifests (@pxref{Invoking guix package, the
4571 @option{--manifest} option of @command{guix package}}). Thus you can insert
4572 an inferior package pretty much anywhere you would insert a regular package:
4573 in manifests, in the @code{packages} field of your @code{operating-system}
4574 declaration, and so on.
4576 @node Invoking guix describe
4577 @section Invoking @command{guix describe}
4579 @cindex reproducibility
4580 @cindex replicating Guix
4581 Often you may want to answer questions like: ``Which revision of Guix am I
4582 using?'' or ``Which channels am I using?'' This is useful information in many
4583 situations: if you want to @emph{replicate} an environment on a different
4584 machine or user account, if you want to report a bug or to determine what
4585 change in the channels you are using caused it, or if you want to record your
4586 system state for reproducibility purposes. The @command{guix describe}
4587 command answers these questions.
4589 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4590 displays the channel(s) that it was built from, including their repository URL
4591 and commit IDs (@pxref{Channels}):
4595 Generation 10 Sep 03 2018 17:32:44 (current)
4597 repository URL: https://git.savannah.gnu.org/git/guix.git
4599 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4602 If you're familiar with the Git version control system, this is similar in
4603 spirit to @command{git describe}; the output is also similar to that of
4604 @command{guix pull --list-generations}, but limited to the current generation
4605 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4606 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4607 information is all it takes to describe the revision of Guix you're using, and
4608 also to replicate it.
4610 To make it easier to replicate Guix, @command{guix describe} can also be asked
4611 to return a list of channels instead of the human-readable description above:
4614 $ guix describe -f channels
4617 (url "https://git.savannah.gnu.org/git/guix.git")
4619 "e0fa68c7718fffd33d81af415279d6ddb518f727")
4621 (make-channel-introduction
4622 "9edb3f66fd807b096b48283debdcddccfea34bad"
4623 (openpgp-fingerprint
4624 "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
4628 You can save this to a file and feed it to @command{guix pull -C} on some
4629 other machine or at a later point in time, which will instantiate @emph{this
4630 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4631 From there on, since you're able to deploy the same revision of Guix, you can
4632 just as well @emph{replicate a complete software environment}. We humbly
4633 think that this is @emph{awesome}, and we hope you'll like it too!
4635 The details of the options supported by @command{guix describe} are as
4639 @item --format=@var{format}
4640 @itemx -f @var{format}
4641 Produce output in the specified @var{format}, one of:
4645 produce human-readable output;
4647 produce a list of channel specifications that can be passed to @command{guix
4648 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4650 @item channels-sans-intro
4651 like @code{channels}, but omit the @code{introduction} field; use it to
4652 produce a channel specification suitable for Guix version 1.1.0 or
4653 earlier---the @code{introduction} field has to do with channel
4654 authentication (@pxref{Channels, Channel Authentication}) and is not
4655 supported by these older versions;
4658 produce a list of channel specifications in JSON format;
4660 produce a list of channel specifications in Recutils format.
4663 @item --list-formats
4664 Display available formats for @option{--format} option.
4666 @item --profile=@var{profile}
4667 @itemx -p @var{profile}
4668 Display information about @var{profile}.
4671 @node Invoking guix archive
4672 @section Invoking @command{guix archive}
4674 @cindex @command{guix archive}
4676 The @command{guix archive} command allows users to @dfn{export} files
4677 from the store into a single archive, and to later @dfn{import} them on
4678 a machine that runs Guix.
4679 In particular, it allows store files to be transferred from one machine
4680 to the store on another machine.
4683 If you're looking for a way to produce archives in a format suitable for
4684 tools other than Guix, @pxref{Invoking guix pack}.
4687 @cindex exporting store items
4688 To export store files as an archive to standard output, run:
4691 guix archive --export @var{options} @var{specifications}...
4694 @var{specifications} may be either store file names or package
4695 specifications, as for @command{guix package} (@pxref{Invoking guix
4696 package}). For instance, the following command creates an archive
4697 containing the @code{gui} output of the @code{git} package and the main
4698 output of @code{emacs}:
4701 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4704 If the specified packages are not built yet, @command{guix archive}
4705 automatically builds them. The build process may be controlled with the
4706 common build options (@pxref{Common Build Options}).
4708 To transfer the @code{emacs} package to a machine connected over SSH,
4712 guix archive --export -r emacs | ssh the-machine guix archive --import
4716 Similarly, a complete user profile may be transferred from one machine
4717 to another like this:
4720 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4721 ssh the-machine guix archive --import
4725 However, note that, in both examples, all of @code{emacs} and the
4726 profile as well as all of their dependencies are transferred (due to
4727 @option{-r}), regardless of what is already available in the store on
4728 the target machine. The @option{--missing} option can help figure out
4729 which items are missing from the target store. The @command{guix copy}
4730 command simplifies and optimizes this whole process, so this is probably
4731 what you should use in this case (@pxref{Invoking guix copy}).
4733 @cindex nar, archive format
4734 @cindex normalized archive (nar)
4735 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4736 comparable in spirit to `tar', but with differences
4737 that make it more appropriate for our purposes. First, rather than
4738 recording all Unix metadata for each file, the nar format only mentions
4739 the file type (regular, directory, or symbolic link); Unix permissions
4740 and owner/group are dismissed. Second, the order in which directory
4741 entries are stored always follows the order of file names according to
4742 the C locale collation order. This makes archive production fully
4745 When exporting, the daemon digitally signs the contents of the archive,
4746 and that digital signature is appended. When importing, the daemon
4747 verifies the signature and rejects the import in case of an invalid
4748 signature or if the signing key is not authorized.
4749 @c FIXME: Add xref to daemon doc about signatures.
4751 The main options are:
4755 Export the specified store files or packages (see below). Write the
4756 resulting archive to the standard output.
4758 Dependencies are @emph{not} included in the output, unless
4759 @option{--recursive} is passed.
4763 When combined with @option{--export}, this instructs @command{guix archive}
4764 to include dependencies of the given items in the archive. Thus, the
4765 resulting archive is self-contained: it contains the closure of the
4766 exported store items.
4769 Read an archive from the standard input, and import the files listed
4770 therein into the store. Abort if the archive has an invalid digital
4771 signature, or if it is signed by a public key not among the authorized
4772 keys (see @option{--authorize} below).
4775 Read a list of store file names from the standard input, one per line,
4776 and write on the standard output the subset of these files missing from
4779 @item --generate-key[=@var{parameters}]
4780 @cindex signing, archives
4781 Generate a new key pair for the daemon. This is a prerequisite before
4782 archives can be exported with @option{--export}. Note that this
4783 operation usually takes time, because it needs to gather enough entropy
4784 to generate the key pair.
4786 The generated key pair is typically stored under @file{/etc/guix}, in
4787 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4788 key, which must be kept secret). When @var{parameters} is omitted,
4789 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4790 versions before 1.6.0, it is a 4096-bit RSA key.
4791 Alternatively, @var{parameters} can specify
4792 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4793 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4794 Libgcrypt Reference Manual}).
4797 @cindex authorizing, archives
4798 Authorize imports signed by the public key passed on standard input.
4799 The public key must be in ``s-expression advanced format''---i.e., the
4800 same format as the @file{signing-key.pub} file.
4802 The list of authorized keys is kept in the human-editable file
4803 @file{/etc/guix/acl}. The file contains
4804 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4805 s-expressions''} and is structured as an access-control list in the
4806 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4809 @item --extract=@var{directory}
4810 @itemx -x @var{directory}
4811 Read a single-item archive as served by substitute servers
4812 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4813 low-level operation needed in only very narrow use cases; see below.
4815 For example, the following command extracts the substitute for Emacs
4816 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4820 https://@value{SUBSTITUTE-SERVER}/nar/gzip/@dots{}-emacs-24.5 \
4821 | gunzip | guix archive -x /tmp/emacs
4824 Single-item archives are different from multiple-item archives produced
4825 by @command{guix archive --export}; they contain a single store item,
4826 and they do @emph{not} embed a signature. Thus this operation does
4827 @emph{no} signature verification and its output should be considered
4830 The primary purpose of this operation is to facilitate inspection of
4831 archive contents coming from possibly untrusted substitute servers
4832 (@pxref{Invoking guix challenge}).
4836 Read a single-item archive as served by substitute servers
4837 (@pxref{Substitutes}) and print the list of files it contains, as in
4842 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4843 | lzip -d | guix archive -t
4849 @c *********************************************************************
4851 @chapter Development
4853 @cindex software development
4854 If you are a software developer, Guix provides tools that you should find
4855 helpful---independently of the language you're developing in. This is what
4856 this chapter is about.
4858 The @command{guix environment} command provides a convenient way to set up
4859 @dfn{development environments} containing all the dependencies and tools
4860 necessary to work on the software package of your choice. The @command{guix
4861 pack} command allows you to create @dfn{application bundles} that can be
4862 easily distributed to users who do not run Guix.
4865 * Invoking guix environment:: Setting up development environments.
4866 * Invoking guix pack:: Creating software bundles.
4867 * The GCC toolchain:: Working with languages supported by GCC.
4870 @node Invoking guix environment
4871 @section Invoking @command{guix environment}
4873 @cindex reproducible build environments
4874 @cindex development environments
4875 @cindex @command{guix environment}
4876 @cindex environment, package build environment
4877 The purpose of @command{guix environment} is to assist hackers in
4878 creating reproducible development environments without polluting their
4879 package profile. The @command{guix environment} tool takes one or more
4880 packages, builds all of their inputs, and creates a shell
4881 environment to use them.
4883 The general syntax is:
4886 guix environment @var{options} @var{package}@dots{}
4889 The following example spawns a new shell set up for the development of
4893 guix environment guile
4896 If the needed dependencies are not built yet, @command{guix environment}
4897 automatically builds them. The environment of the new shell is an
4898 augmented version of the environment that @command{guix environment} was
4899 run in. It contains the necessary search paths for building the given
4900 package added to the existing environment variables. To create
4901 a ``pure'' environment, in which the original environment variables have
4902 been unset, use the @option{--pure} option@footnote{Users sometimes
4903 wrongfully augment environment variables such as @env{PATH} in their
4904 @file{~/.bashrc} file. As a consequence, when @command{guix
4905 environment} launches it, Bash may read @file{~/.bashrc}, thereby
4906 introducing ``impurities'' in these environment variables. It is an
4907 error to define such environment variables in @file{.bashrc}; instead,
4908 they should be defined in @file{.bash_profile}, which is sourced only by
4909 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
4910 Manual}, for details on Bash start-up files.}.
4912 @vindex GUIX_ENVIRONMENT
4913 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
4914 variable in the shell it spawns; its value is the file name of the
4915 profile of this environment. This allows users to, say, define a
4916 specific prompt for development environments in their @file{.bashrc}
4917 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4920 if [ -n "$GUIX_ENVIRONMENT" ]
4922 export PS1="\u@@\h \w [dev]\$ "
4927 ...@: or to browse the profile:
4930 $ ls "$GUIX_ENVIRONMENT/bin"
4933 Additionally, more than one package may be specified, in which case the
4934 union of the inputs for the given packages are used. For example, the
4935 command below spawns a shell where all of the dependencies of both Guile
4936 and Emacs are available:
4939 guix environment guile emacs
4942 Sometimes an interactive shell session is not desired. An arbitrary
4943 command may be invoked by placing the @code{--} token to separate the
4944 command from the rest of the arguments:
4947 guix environment guile -- make -j4
4950 In other situations, it is more convenient to specify the list of
4951 packages needed in the environment. For example, the following command
4952 runs @command{python} from an environment containing Python@tie{}2.7 and
4956 guix environment --ad-hoc python2-numpy python-2.7 -- python
4959 Furthermore, one might want the dependencies of a package and also some
4960 additional packages that are not build-time or runtime dependencies, but
4961 are useful when developing nonetheless. Because of this, the
4962 @option{--ad-hoc} flag is positional. Packages appearing before
4963 @option{--ad-hoc} are interpreted as packages whose dependencies will be
4964 added to the environment. Packages appearing after are interpreted as
4965 packages that will be added to the environment directly. For example,
4966 the following command creates a Guix development environment that
4967 additionally includes Git and strace:
4970 guix environment --pure guix --ad-hoc git strace
4974 Sometimes it is desirable to isolate the environment as much as
4975 possible, for maximal purity and reproducibility. In particular, when
4976 using Guix on a host distro that is not Guix System, it is desirable to
4977 prevent access to @file{/usr/bin} and other system-wide resources from
4978 the development environment. For example, the following command spawns
4979 a Guile REPL in a ``container'' where only the store and the current
4980 working directory are mounted:
4983 guix environment --ad-hoc --container guile -- guile
4987 The @option{--container} option requires Linux-libre 3.19 or newer.
4990 @cindex certificates
4991 Another typical use case for containers is to run security-sensitive
4992 applications such as a web browser. To run Eolie, we must expose and
4993 share some files and directories; we include @code{nss-certs} and expose
4994 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
4995 the @env{DISPLAY} environment variable since containerized graphical
4996 applications won't display without it.
4999 guix environment --preserve='^DISPLAY$' --container --network \
5000 --expose=/etc/machine-id \
5001 --expose=/etc/ssl/certs/ \
5002 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
5003 --ad-hoc eolie nss-certs dbus -- eolie
5006 The available options are summarized below.
5009 @item --root=@var{file}
5010 @itemx -r @var{file}
5011 @cindex persistent environment
5012 @cindex garbage collector root, for environments
5013 Make @var{file} a symlink to the profile for this environment, and
5014 register it as a garbage collector root.
5016 This is useful if you want to protect your environment from garbage
5017 collection, to make it ``persistent''.
5019 When this option is omitted, the environment is protected from garbage
5020 collection only for the duration of the @command{guix environment}
5021 session. This means that next time you recreate the same environment,
5022 you could have to rebuild or re-download packages. @xref{Invoking guix
5023 gc}, for more on GC roots.
5025 @item --expression=@var{expr}
5026 @itemx -e @var{expr}
5027 Create an environment for the package or list of packages that
5028 @var{expr} evaluates to.
5030 For example, running:
5033 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
5036 starts a shell with the environment for this specific variant of the
5042 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
5045 starts a shell with all the base system packages available.
5047 The above commands only use the default output of the given packages.
5048 To select other outputs, two element tuples can be specified:
5051 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
5054 @item --load=@var{file}
5055 @itemx -l @var{file}
5056 Create an environment for the package or list of packages that the code
5057 within @var{file} evaluates to.
5059 As an example, @var{file} might contain a definition like this
5060 (@pxref{Defining Packages}):
5063 @verbatiminclude environment-gdb.scm
5066 @item --manifest=@var{file}
5067 @itemx -m @var{file}
5068 Create an environment for the packages contained in the manifest object
5069 returned by the Scheme code in @var{file}. This option can be repeated
5070 several times, in which case the manifests are concatenated.
5072 This is similar to the same-named option in @command{guix package}
5073 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
5077 Include all specified packages in the resulting environment, as if an
5078 @i{ad hoc} package were defined with them as inputs. This option is
5079 useful for quickly creating an environment without having to write a
5080 package expression to contain the desired inputs.
5082 For instance, the command:
5085 guix environment --ad-hoc guile guile-sdl -- guile
5088 runs @command{guile} in an environment where Guile and Guile-SDL are
5091 Note that this example implicitly asks for the default output of
5092 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
5093 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
5094 of @code{glib} (@pxref{Packages with Multiple Outputs}).
5096 This option may be composed with the default behavior of @command{guix
5097 environment}. Packages appearing before @option{--ad-hoc} are
5098 interpreted as packages whose dependencies will be added to the
5099 environment, the default behavior. Packages appearing after are
5100 interpreted as packages that will be added to the environment directly.
5103 Unset existing environment variables when building the new environment, except
5104 those specified with @option{--preserve} (see below). This has the effect of
5105 creating an environment in which search paths only contain package inputs.
5107 @item --preserve=@var{regexp}
5108 @itemx -E @var{regexp}
5109 When used alongside @option{--pure}, preserve the environment variables
5110 matching @var{regexp}---in other words, put them on a ``white list'' of
5111 environment variables that must be preserved. This option can be repeated
5115 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
5119 This example runs @command{mpirun} in a context where the only environment
5120 variables defined are @env{PATH}, environment variables whose name starts
5121 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
5124 @item --search-paths
5125 Display the environment variable definitions that make up the
5128 @item --system=@var{system}
5129 @itemx -s @var{system}
5130 Attempt to build for @var{system}---e.g., @code{i686-linux}.
5135 Run @var{command} within an isolated container. The current working
5136 directory outside the container is mapped inside the container.
5137 Additionally, unless overridden with @option{--user}, a dummy home
5138 directory is created that matches the current user's home directory, and
5139 @file{/etc/passwd} is configured accordingly.
5141 The spawned process runs as the current user outside the container. Inside
5142 the container, it has the same UID and GID as the current user, unless
5143 @option{--user} is passed (see below).
5147 For containers, share the network namespace with the host system.
5148 Containers created without this flag only have access to the loopback
5151 @item --link-profile
5153 For containers, link the environment profile to @file{~/.guix-profile}
5154 within the container. This is equivalent to running the command
5155 @samp{ln -s $GUIX_ENVIRONMENT ~/.guix-profile} within the container.
5156 Linking will fail and abort the environment if the directory already
5157 exists, which will certainly be the case if @command{guix environment}
5158 was invoked in the user's home directory.
5160 Certain packages are configured to look in @file{~/.guix-profile} for
5161 configuration files and data;@footnote{For example, the
5162 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
5163 for additional fonts.} @option{--link-profile} allows these programs to
5164 behave as expected within the environment.
5166 @item --user=@var{user}
5167 @itemx -u @var{user}
5168 For containers, use the username @var{user} in place of the current
5169 user. The generated @file{/etc/passwd} entry within the container will
5170 contain the name @var{user}, the home directory will be
5171 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
5172 the UID and GID inside the container are 1000. @var{user}
5173 need not exist on the system.
5175 Additionally, any shared or exposed path (see @option{--share} and
5176 @option{--expose} respectively) whose target is within the current user's
5177 home directory will be remapped relative to @file{/home/USER}; this
5178 includes the automatic mapping of the current working directory.
5181 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
5183 guix environment --container --user=foo \
5184 --expose=$HOME/test \
5185 --expose=/tmp/target=$HOME/target
5188 While this will limit the leaking of user identity through home paths
5189 and each of the user fields, this is only one useful component of a
5190 broader privacy/anonymity solution---not one in and of itself.
5193 For containers, the default behavior is to share the current working
5194 directory with the isolated container and immediately change to that
5195 directory within the container. If this is undesirable,
5196 @option{--no-cwd} will cause the current working directory to @emph{not}
5197 be automatically shared and will change to the user's home directory
5198 within the container instead. See also @option{--user}.
5200 @item --expose=@var{source}[=@var{target}]
5201 @itemx --share=@var{source}[=@var{target}]
5202 For containers, @option{--expose} (resp. @option{--share}) exposes the
5203 file system @var{source} from the host system as the read-only
5204 (resp. writable) file system @var{target} within the container. If
5205 @var{target} is not specified, @var{source} is used as the target mount
5206 point in the container.
5208 The example below spawns a Guile REPL in a container in which the user's
5209 home directory is accessible read-only via the @file{/exchange}
5213 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
5218 @command{guix environment}
5219 also supports all of the common build options that @command{guix
5220 build} supports (@pxref{Common Build Options}) as well as package
5221 transformation options (@pxref{Package Transformation Options}).
5223 @node Invoking guix pack
5224 @section Invoking @command{guix pack}
5226 Occasionally you want to pass software to people who are not (yet!)
5227 lucky enough to be using Guix. You'd tell them to run @command{guix
5228 package -i @var{something}}, but that's not possible in this case. This
5229 is where @command{guix pack} comes in.
5232 If you are looking for ways to exchange binaries among machines that
5233 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5234 publish}, and @ref{Invoking guix archive}.
5239 @cindex application bundle
5240 @cindex software bundle
5241 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5242 @dfn{software bundle}: it creates a tarball or some other archive
5243 containing the binaries of the software you're interested in, and all
5244 its dependencies. The resulting archive can be used on any machine that
5245 does not have Guix, and people can run the exact same binaries as those
5246 you have with Guix. The pack itself is created in a bit-reproducible
5247 fashion, so anyone can verify that it really contains the build results
5248 that you pretend to be shipping.
5250 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5251 their dependencies, you can run:
5254 $ guix pack guile emacs geiser
5256 /gnu/store/@dots{}-pack.tar.gz
5259 The result here is a tarball containing a @file{/gnu/store} directory
5260 with all the relevant packages. The resulting tarball contains a
5261 @dfn{profile} with the three packages of interest; the profile is the
5262 same as would be created by @command{guix package -i}. It is this
5263 mechanism that is used to create Guix's own standalone binary tarball
5264 (@pxref{Binary Installation}).
5266 Users of this pack would have to run
5267 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5268 find inconvenient. To work around it, you can create, say, a
5269 @file{/opt/gnu/bin} symlink to the profile:
5272 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5276 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5278 @cindex relocatable binaries, with @command{guix pack}
5279 What if the recipient of your pack does not have root privileges on
5280 their machine, and thus cannot unpack it in the root file system? In
5281 that case, you will want to use the @option{--relocatable} option (see
5282 below). This option produces @dfn{relocatable binaries}, meaning they
5283 they can be placed anywhere in the file system hierarchy: in the example
5284 above, users can unpack your tarball in their home directory and
5285 directly run @file{./opt/gnu/bin/guile}.
5287 @cindex Docker, build an image with guix pack
5288 Alternatively, you can produce a pack in the Docker image format using
5289 the following command:
5292 guix pack -f docker -S /bin=bin guile guile-readline
5296 The result is a tarball that can be passed to the @command{docker load}
5297 command, followed by @code{docker run}:
5300 docker load < @var{file}
5301 docker run -ti guile-guile-readline /bin/guile
5305 where @var{file} is the image returned by @var{guix pack}, and
5306 @code{guile-guile-readline} is its ``image tag''. See the
5307 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5308 documentation} for more information.
5310 @cindex Singularity, build an image with guix pack
5311 @cindex SquashFS, build an image with guix pack
5312 Yet another option is to produce a SquashFS image with the following
5316 guix pack -f squashfs bash guile emacs geiser
5320 The result is a SquashFS file system image that can either be mounted or
5321 directly be used as a file system container image with the
5322 @uref{https://www.sylabs.io/docs/, Singularity container execution
5323 environment}, using commands like @command{singularity shell} or
5324 @command{singularity exec}.
5326 Several command-line options allow you to customize your pack:
5329 @item --format=@var{format}
5330 @itemx -f @var{format}
5331 Produce a pack in the given @var{format}.
5333 The available formats are:
5337 This is the default format. It produces a tarball containing all the
5338 specified binaries and symlinks.
5341 This produces a tarball that follows the
5342 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
5343 Docker Image Specification}. The ``repository name'' as it appears in
5344 the output of the @command{docker images} command is computed from
5345 package names passed on the command line or in the manifest file.
5348 This produces a SquashFS image containing all the specified binaries and
5349 symlinks, as well as empty mount points for virtual file systems like
5353 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
5354 For that reason, @command{guix pack -f squashfs} always implies @code{-S
5355 /bin=bin}. Thus, your @command{guix pack} invocation must always start
5356 with something like:
5359 guix pack -f squashfs bash @dots{}
5362 If you forget the @code{bash} (or similar) package, @command{singularity
5363 run} and @command{singularity exec} will fail with an unhelpful ``no
5364 such file or directory'' message.
5368 @cindex relocatable binaries
5371 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
5372 anywhere in the file system hierarchy and run from there.
5374 When this option is passed once, the resulting binaries require support for
5375 @dfn{user namespaces} in the kernel Linux; when passed
5376 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
5377 PRoot support, can be thought of as the abbreviation of ``Really
5378 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
5379 other techniques if user namespaces are unavailable, and essentially
5380 work anywhere---see below for the implications.
5382 For example, if you create a pack containing Bash with:
5385 guix pack -RR -S /mybin=bin bash
5389 ...@: you can copy that pack to a machine that lacks Guix, and from your
5390 home directory as a normal user, run:
5398 In that shell, if you type @code{ls /gnu/store}, you'll notice that
5399 @file{/gnu/store} shows up and contains all the dependencies of
5400 @code{bash}, even though the machine actually lacks @file{/gnu/store}
5401 altogether! That is probably the simplest way to deploy Guix-built
5402 software on a non-Guix machine.
5405 By default, relocatable binaries rely on the @dfn{user namespace} feature of
5406 the kernel Linux, which allows unprivileged users to mount or change root.
5407 Old versions of Linux did not support it, and some GNU/Linux distributions
5410 To produce relocatable binaries that work even in the absence of user
5411 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
5412 case, binaries will try user namespace support and fall back to another
5413 @dfn{execution engine} if user namespaces are not supported. The
5414 following execution engines are supported:
5418 Try user namespaces and fall back to PRoot if user namespaces are not
5419 supported (see below).
5422 Try user namespaces and fall back to Fakechroot if user namespaces are
5423 not supported (see below).
5426 Run the program through user namespaces and abort if they are not
5430 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
5431 provides the necessary
5432 support for file system virtualization. It achieves that by using the
5433 @code{ptrace} system call on the running program. This approach has the
5434 advantage to work without requiring special kernel support, but it incurs
5435 run-time overhead every time a system call is made.
5438 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
5439 Fakechroot} virtualizes file system accesses by intercepting calls to C
5440 library functions such as @code{open}, @code{stat}, @code{exec}, and so
5441 on. Unlike PRoot, it incurs very little overhead. However, it does not
5442 always work: for example, some file system accesses made from within the
5443 C library are not intercepted, and file system accesses made @i{via}
5444 direct syscalls are not intercepted either, leading to erratic behavior.
5447 @vindex GUIX_EXECUTION_ENGINE
5448 When running a wrapped program, you can explicitly request one of the
5449 execution engines listed above by setting the
5450 @code{GUIX_EXECUTION_ENGINE} environment variable accordingly.
5453 @cindex entry point, for Docker images
5454 @item --entry-point=@var{command}
5455 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
5456 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
5457 support it. @var{command} must be relative to the profile contained in the
5460 The entry point specifies the command that tools like @code{docker run} or
5461 @code{singularity run} automatically start by default. For example, you can
5465 guix pack -f docker --entry-point=bin/guile guile
5468 The resulting pack can easily be loaded and @code{docker run} with no extra
5469 arguments will spawn @code{bin/guile}:
5472 docker load -i pack.tar.gz
5473 docker run @var{image-id}
5476 @item --expression=@var{expr}
5477 @itemx -e @var{expr}
5478 Consider the package @var{expr} evaluates to.
5480 This has the same purpose as the same-named option in @command{guix
5481 build} (@pxref{Additional Build Options, @option{--expression} in
5482 @command{guix build}}).
5484 @item --manifest=@var{file}
5485 @itemx -m @var{file}
5486 Use the packages contained in the manifest object returned by the Scheme
5487 code in @var{file}. This option can be repeated several times, in which
5488 case the manifests are concatenated.
5490 This has a similar purpose as the same-named option in @command{guix
5491 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
5492 same manifest files. It allows you to define a collection of packages
5493 once and use it both for creating profiles and for creating archives
5494 for use on machines that do not have Guix installed. Note that you can
5495 specify @emph{either} a manifest file @emph{or} a list of packages,
5498 @item --system=@var{system}
5499 @itemx -s @var{system}
5500 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
5501 the system type of the build host.
5503 @item --target=@var{triplet}
5504 @cindex cross-compilation
5505 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
5506 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
5507 configuration triplets,, autoconf, Autoconf}).
5509 @item --compression=@var{tool}
5510 @itemx -C @var{tool}
5511 Compress the resulting tarball using @var{tool}---one of @code{gzip},
5512 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
5515 @item --symlink=@var{spec}
5516 @itemx -S @var{spec}
5517 Add the symlinks specified by @var{spec} to the pack. This option can
5518 appear several times.
5520 @var{spec} has the form @code{@var{source}=@var{target}}, where
5521 @var{source} is the symlink that will be created and @var{target} is the
5524 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
5525 symlink pointing to the @file{bin} sub-directory of the profile.
5527 @item --save-provenance
5528 Save provenance information for the packages passed on the command line.
5529 Provenance information includes the URL and commit of the channels in use
5532 Provenance information is saved in the
5533 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
5534 usual package metadata---the name and version of each package, their
5535 propagated inputs, and so on. It is useful information to the recipient of
5536 the pack, who then knows how the pack was (supposedly) obtained.
5538 This option is not enabled by default because, like timestamps, provenance
5539 information contributes nothing to the build process. In other words, there
5540 is an infinity of channel URLs and commit IDs that can lead to the same pack.
5541 Recording such ``silent'' metadata in the output thus potentially breaks the
5542 source-to-binary bitwise reproducibility property.
5544 @item --root=@var{file}
5545 @itemx -r @var{file}
5546 @cindex garbage collector root, for packs
5547 Make @var{file} a symlink to the resulting pack, and register it as a garbage
5550 @item --localstatedir
5551 @itemx --profile-name=@var{name}
5552 Include the ``local state directory'', @file{/var/guix}, in the resulting
5553 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
5554 profile---by default @var{name} is @code{guix-profile}, which corresponds to
5555 @file{~root/.guix-profile}.
5557 @file{/var/guix} contains the store database (@pxref{The Store}) as well
5558 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
5559 the pack means that the store is ``complete'' and manageable by Guix;
5560 not providing it pack means that the store is ``dead'': items cannot be
5561 added to it or removed from it after extraction of the pack.
5563 One use case for this is the Guix self-contained binary tarball
5564 (@pxref{Binary Installation}).
5568 Print the name of the derivation that builds the pack.
5571 Use the bootstrap binaries to build the pack. This option is only
5572 useful to Guix developers.
5575 In addition, @command{guix pack} supports all the common build options
5576 (@pxref{Common Build Options}) and all the package transformation
5577 options (@pxref{Package Transformation Options}).
5580 @node The GCC toolchain
5581 @section The GCC toolchain
5585 @cindex linker wrapper
5586 @cindex toolchain, for C development
5587 @cindex toolchain, for Fortran development
5589 If you need a complete toolchain for compiling and linking C or C++
5590 source code, use the @code{gcc-toolchain} package. This package
5591 provides a complete GCC toolchain for C/C++ development, including GCC
5592 itself, the GNU C Library (headers and binaries, plus debugging symbols
5593 in the @code{debug} output), Binutils, and a linker wrapper.
5595 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
5596 passed to the linker, add corresponding @code{-rpath} arguments, and
5597 invoke the actual linker with this new set of arguments. You can instruct the
5598 wrapper to refuse to link against libraries not in the store by setting the
5599 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
5601 The package @code{gfortran-toolchain} provides a complete GCC toolchain
5602 for Fortran development. For other languages, please use
5603 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
5605 @c *********************************************************************
5606 @node Programming Interface
5607 @chapter Programming Interface
5609 GNU Guix provides several Scheme programming interfaces (APIs) to
5610 define, build, and query packages. The first interface allows users to
5611 write high-level package definitions. These definitions refer to
5612 familiar packaging concepts, such as the name and version of a package,
5613 its build system, and its dependencies. These definitions can then be
5614 turned into concrete build actions.
5616 Build actions are performed by the Guix daemon, on behalf of users. In a
5617 standard setup, the daemon has write access to the store---the
5618 @file{/gnu/store} directory---whereas users do not. The recommended
5619 setup also has the daemon perform builds in chroots, under specific
5620 build users, to minimize interference with the rest of the system.
5623 Lower-level APIs are available to interact with the daemon and the
5624 store. To instruct the daemon to perform a build action, users actually
5625 provide it with a @dfn{derivation}. A derivation is a low-level
5626 representation of the build actions to be taken, and the environment in
5627 which they should occur---derivations are to package definitions what
5628 assembly is to C programs. The term ``derivation'' comes from the fact
5629 that build results @emph{derive} from them.
5631 This chapter describes all these APIs in turn, starting from high-level
5632 package definitions.
5635 * Package Modules:: Packages from the programmer's viewpoint.
5636 * Defining Packages:: Defining new packages.
5637 * Build Systems:: Specifying how packages are built.
5638 * The Store:: Manipulating the package store.
5639 * Derivations:: Low-level interface to package derivations.
5640 * The Store Monad:: Purely functional interface to the store.
5641 * G-Expressions:: Manipulating build expressions.
5642 * Invoking guix repl:: Programming Guix in Guile
5645 @node Package Modules
5646 @section Package Modules
5648 From a programming viewpoint, the package definitions of the
5649 GNU distribution are provided by Guile modules in the @code{(gnu packages
5650 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5651 packages @dots{})} module name space are not necessarily ``GNU
5652 packages''. This module naming scheme follows the usual Guile module
5653 naming convention: @code{gnu} means that these modules are distributed
5654 as part of the GNU system, and @code{packages} identifies modules that
5655 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5656 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5657 module exports a variable named @code{emacs}, which is bound to a
5658 @code{<package>} object (@pxref{Defining Packages}).
5660 The @code{(gnu packages @dots{})} module name space is
5661 automatically scanned for packages by the command-line tools. For
5662 instance, when running @code{guix install emacs}, all the @code{(gnu
5663 packages @dots{})} modules are scanned until one that exports a package
5664 object whose name is @code{emacs} is found. This package search
5665 facility is implemented in the @code{(gnu packages)} module.
5667 @cindex customization, of packages
5668 @cindex package module search path
5669 Users can store package definitions in modules with different
5670 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5671 name and module name must match. For instance, the @code{(my-packages
5672 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5673 relative to the load path specified with @option{--load-path} or
5674 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5675 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5676 these package definitions visible to the user interfaces:
5680 By adding the directory containing your package modules to the search path
5681 with the @code{-L} flag of @command{guix package} and other commands
5682 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
5683 environment variable described below.
5686 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5687 pulls from it. A channel is essentially a Git repository containing package
5688 modules. @xref{Channels}, for more information on how to define and use
5692 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5694 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5695 This is a colon-separated list of directories to search for additional
5696 package modules. Directories listed in this variable take precedence
5697 over the own modules of the distribution.
5700 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5701 each package is built based solely on other packages in the
5702 distribution. The root of this dependency graph is a small set of
5703 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5704 bootstrap)} module. For more information on bootstrapping,
5705 @pxref{Bootstrapping}.
5707 @node Defining Packages
5708 @section Defining Packages
5710 The high-level interface to package definitions is implemented in the
5711 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5712 example, the package definition, or @dfn{recipe}, for the GNU Hello
5713 package looks like this:
5716 (define-module (gnu packages hello)
5717 #:use-module (guix packages)
5718 #:use-module (guix download)
5719 #:use-module (guix build-system gnu)
5720 #:use-module (guix licenses)
5721 #:use-module (gnu packages gawk))
5723 (define-public hello
5729 (uri (string-append "mirror://gnu/hello/hello-" version
5733 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5734 (build-system gnu-build-system)
5735 (arguments '(#:configure-flags '("--enable-silent-rules")))
5736 (inputs `(("gawk" ,gawk)))
5737 (synopsis "Hello, GNU world: An example GNU package")
5738 (description "Guess what GNU Hello prints!")
5739 (home-page "https://www.gnu.org/software/hello/")
5744 Without being a Scheme expert, the reader may have guessed the meaning
5745 of the various fields here. This expression binds the variable
5746 @code{hello} to a @code{<package>} object, which is essentially a record
5747 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5748 This package object can be inspected using procedures found in the
5749 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5750 returns---surprise!---@code{"hello"}.
5752 With luck, you may be able to import part or all of the definition of
5753 the package you are interested in from another repository, using the
5754 @code{guix import} command (@pxref{Invoking guix import}).
5756 In the example above, @var{hello} is defined in a module of its own,
5757 @code{(gnu packages hello)}. Technically, this is not strictly
5758 necessary, but it is convenient to do so: all the packages defined in
5759 modules under @code{(gnu packages @dots{})} are automatically known to
5760 the command-line tools (@pxref{Package Modules}).
5762 There are a few points worth noting in the above package definition:
5766 The @code{source} field of the package is an @code{<origin>} object
5767 (@pxref{origin Reference}, for the complete reference).
5768 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5769 meaning that the source is a file to be downloaded over FTP or HTTP.
5771 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5772 the GNU mirrors defined in @code{(guix download)}.
5774 The @code{sha256} field specifies the expected SHA256 hash of the file
5775 being downloaded. It is mandatory, and allows Guix to check the
5776 integrity of the file. The @code{(base32 @dots{})} form introduces the
5777 base32 representation of the hash. You can obtain this information with
5778 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5779 hash} (@pxref{Invoking guix hash}).
5782 When needed, the @code{origin} form can also have a @code{patches} field
5783 listing patches to be applied, and a @code{snippet} field giving a
5784 Scheme expression to modify the source code.
5787 @cindex GNU Build System
5788 The @code{build-system} field specifies the procedure to build the
5789 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5790 represents the familiar GNU Build System, where packages may be
5791 configured, built, and installed with the usual @code{./configure &&
5792 make && make check && make install} command sequence.
5795 The @code{arguments} field specifies options for the build system
5796 (@pxref{Build Systems}). Here it is interpreted by
5797 @var{gnu-build-system} as a request run @file{configure} with the
5798 @option{--enable-silent-rules} flag.
5804 What about these quote (@code{'}) characters? They are Scheme syntax to
5805 introduce a literal list; @code{'} is synonymous with @code{quote}.
5806 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5807 for details. Here the value of the @code{arguments} field is a list of
5808 arguments passed to the build system down the road, as with @code{apply}
5809 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5812 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5813 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5814 @code{#:configure-flags} is a keyword used to pass a keyword argument
5815 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5819 The @code{inputs} field specifies inputs to the build process---i.e.,
5820 build-time or run-time dependencies of the package. Here, we define an
5821 input called @code{"gawk"} whose value is that of the @var{gawk}
5822 variable; @var{gawk} is itself bound to a @code{<package>} object.
5824 @cindex backquote (quasiquote)
5827 @cindex comma (unquote)
5831 @findex unquote-splicing
5832 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5833 us to introduce a literal list in the @code{inputs} field, while
5834 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5835 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5838 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5839 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5840 of ensuring that they are present (@pxref{Build Systems}).
5842 However, any other dependencies need to be specified in the
5843 @code{inputs} field. Any dependency not specified here will simply be
5844 unavailable to the build process, possibly leading to a build failure.
5847 @xref{package Reference}, for a full description of possible fields.
5849 Once a package definition is in place, the
5850 package may actually be built using the @code{guix build} command-line
5851 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5852 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5853 package definition using the @command{guix edit} command
5854 (@pxref{Invoking guix edit}).
5855 @xref{Packaging Guidelines}, for
5856 more information on how to test package definitions, and
5857 @ref{Invoking guix lint}, for information on how to check a definition
5858 for style conformance.
5859 @vindex GUIX_PACKAGE_PATH
5860 Lastly, @pxref{Channels}, for information
5861 on how to extend the distribution by adding your own package definitions
5864 Finally, updating the package definition to a new upstream version
5865 can be partly automated by the @command{guix refresh} command
5866 (@pxref{Invoking guix refresh}).
5868 Behind the scenes, a derivation corresponding to the @code{<package>}
5869 object is first computed by the @code{package-derivation} procedure.
5870 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
5871 The build actions it prescribes may then be realized by using the
5872 @code{build-derivations} procedure (@pxref{The Store}).
5874 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5875 Return the @code{<derivation>} object of @var{package} for @var{system}
5876 (@pxref{Derivations}).
5878 @var{package} must be a valid @code{<package>} object, and @var{system}
5879 must be a string denoting the target system type---e.g.,
5880 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5881 must be a connection to the daemon, which operates on the store
5882 (@pxref{The Store}).
5886 @cindex cross-compilation
5887 Similarly, it is possible to compute a derivation that cross-builds a
5888 package for some other system:
5890 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5891 @var{package} @var{target} [@var{system}]
5892 Return the @code{<derivation>} object of @var{package} cross-built from
5893 @var{system} to @var{target}.
5895 @var{target} must be a valid GNU triplet denoting the target hardware
5896 and operating system, such as @code{"aarch64-linux-gnu"}
5897 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5900 @cindex package transformations
5901 @cindex input rewriting
5902 @cindex dependency tree rewriting
5903 Packages can be manipulated in arbitrary ways. An example of a useful
5904 transformation is @dfn{input rewriting}, whereby the dependency tree of
5905 a package is rewritten by replacing specific inputs by others:
5907 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5908 [@var{rewrite-name}]
5909 Return a procedure that, when passed a package, replaces its direct and
5910 indirect dependencies (but not its implicit inputs) according to
5911 @var{replacements}. @var{replacements} is a list of package pairs; the
5912 first element of each pair is the package to replace, and the second one
5915 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5916 the name of a package and returns its new name after rewrite.
5920 Consider this example:
5923 (define libressl-instead-of-openssl
5924 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5926 (package-input-rewriting `((,openssl . ,libressl))))
5928 (define git-with-libressl
5929 (libressl-instead-of-openssl git))
5933 Here we first define a rewriting procedure that replaces @var{openssl}
5934 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5935 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5936 This is exactly what the @option{--with-input} command-line option does
5937 (@pxref{Package Transformation Options, @option{--with-input}}).
5939 The following variant of @code{package-input-rewriting} can match packages to
5940 be replaced by name rather than by identity.
5942 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5943 Return a procedure that, given a package, applies the given @var{replacements} to
5944 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5945 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5946 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5947 replacement for that package.
5950 The example above could be rewritten this way:
5953 (define libressl-instead-of-openssl
5954 ;; Replace all the packages called "openssl" with LibreSSL.
5955 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5958 The key difference here is that, this time, packages are matched by spec and
5959 not by identity. In other words, any package in the graph that is called
5960 @code{openssl} will be replaced.
5962 A more generic procedure to rewrite a package dependency graph is
5963 @code{package-mapping}: it supports arbitrary changes to nodes in the
5966 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5967 Return a procedure that, given a package, applies @var{proc} to all the packages
5968 depended on and returns the resulting package. The procedure stops recursion
5969 when @var{cut?} returns true for a given package.
5973 * package Reference:: The package data type.
5974 * origin Reference:: The origin data type.
5978 @node package Reference
5979 @subsection @code{package} Reference
5981 This section summarizes all the options available in @code{package}
5982 declarations (@pxref{Defining Packages}).
5984 @deftp {Data Type} package
5985 This is the data type representing a package recipe.
5989 The name of the package, as a string.
5991 @item @code{version}
5992 The version of the package, as a string.
5995 An object telling how the source code for the package should be
5996 acquired. Most of the time, this is an @code{origin} object, which
5997 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5998 can also be any other ``file-like'' object such as a @code{local-file},
5999 which denotes a file from the local file system (@pxref{G-Expressions,
6000 @code{local-file}}).
6002 @item @code{build-system}
6003 The build system that should be used to build the package (@pxref{Build
6006 @item @code{arguments} (default: @code{'()})
6007 The arguments that should be passed to the build system. This is a
6008 list, typically containing sequential keyword-value pairs.
6010 @item @code{inputs} (default: @code{'()})
6011 @itemx @code{native-inputs} (default: @code{'()})
6012 @itemx @code{propagated-inputs} (default: @code{'()})
6013 @cindex inputs, of packages
6014 These fields list dependencies of the package. Each one is a list of
6015 tuples, where each tuple has a label for the input (a string) as its
6016 first element, a package, origin, or derivation as its second element,
6017 and optionally the name of the output thereof that should be used, which
6018 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
6019 more on package outputs). For example, the list below specifies three
6023 `(("libffi" ,libffi)
6024 ("libunistring" ,libunistring)
6025 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
6028 @cindex cross compilation, package dependencies
6029 The distinction between @code{native-inputs} and @code{inputs} is
6030 necessary when considering cross-compilation. When cross-compiling,
6031 dependencies listed in @code{inputs} are built for the @emph{target}
6032 architecture; conversely, dependencies listed in @code{native-inputs}
6033 are built for the architecture of the @emph{build} machine.
6035 @code{native-inputs} is typically used to list tools needed at
6036 build time, but not at run time, such as Autoconf, Automake, pkg-config,
6037 Gettext, or Bison. @command{guix lint} can report likely mistakes in
6038 this area (@pxref{Invoking guix lint}).
6040 @anchor{package-propagated-inputs}
6041 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
6042 specified packages will be automatically installed alongside the package
6043 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
6044 package}}, for information on how @command{guix package} deals with
6047 For example this is necessary when a C/C++ library needs headers of
6048 another library to compile, or when a pkg-config file refers to another
6049 one @i{via} its @code{Requires} field.
6051 Another example where @code{propagated-inputs} is useful is for languages
6052 that lack a facility to record the run-time search path akin to the
6053 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
6054 more. To ensure that libraries written in those languages can find
6055 library code they depend on at run time, run-time dependencies must be
6056 listed in @code{propagated-inputs} rather than @code{inputs}.
6058 @item @code{outputs} (default: @code{'("out")})
6059 The list of output names of the package. @xref{Packages with Multiple
6060 Outputs}, for typical uses of additional outputs.
6062 @item @code{native-search-paths} (default: @code{'()})
6063 @itemx @code{search-paths} (default: @code{'()})
6064 A list of @code{search-path-specification} objects describing
6065 search-path environment variables honored by the package.
6067 @item @code{replacement} (default: @code{#f})
6068 This must be either @code{#f} or a package object that will be used as a
6069 @dfn{replacement} for this package. @xref{Security Updates, grafts},
6072 @item @code{synopsis}
6073 A one-line description of the package.
6075 @item @code{description}
6076 A more elaborate description of the package.
6078 @item @code{license}
6079 @cindex license, of packages
6080 The license of the package; a value from @code{(guix licenses)},
6081 or a list of such values.
6083 @item @code{home-page}
6084 The URL to the home-page of the package, as a string.
6086 @item @code{supported-systems} (default: @code{%supported-systems})
6087 The list of systems supported by the package, as strings of the form
6088 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
6090 @item @code{location} (default: source location of the @code{package} form)
6091 The source location of the package. It is useful to override this when
6092 inheriting from another package, in which case this field is not
6093 automatically corrected.
6097 @deffn {Scheme Syntax} this-package
6098 When used in the @emph{lexical scope} of a package field definition, this
6099 identifier resolves to the package being defined.
6101 The example below shows how to add a package as a native input of itself when
6109 ;; When cross-compiled, Guile, for example, depends on
6110 ;; a native version of itself. Add it here.
6111 (native-inputs (if (%current-target-system)
6112 `(("self" ,this-package))
6116 It is an error to refer to @code{this-package} outside a package definition.
6119 @node origin Reference
6120 @subsection @code{origin} Reference
6122 This section summarizes all the options available in @code{origin}
6123 declarations (@pxref{Defining Packages}).
6125 @deftp {Data Type} origin
6126 This is the data type representing a source code origin.
6130 An object containing the URI of the source. The object type depends on
6131 the @code{method} (see below). For example, when using the
6132 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
6133 values are: a URL represented as a string, or a list thereof.
6136 A procedure that handles the URI.
6141 @item @var{url-fetch} from @code{(guix download)}
6142 download a file from the HTTP, HTTPS, or FTP URL specified in the
6146 @item @var{git-fetch} from @code{(guix git-download)}
6147 clone the Git version control repository, and check out the revision
6148 specified in the @code{uri} field as a @code{git-reference} object; a
6149 @code{git-reference} looks like this:
6153 (url "https://git.savannah.gnu.org/git/hello.git")
6159 A bytevector containing the SHA-256 hash of the source. This is
6160 equivalent to providing a @code{content-hash} SHA256 object in the
6161 @code{hash} field described below.
6164 The @code{content-hash} object of the source---see below for how to use
6165 @code{content-hash}.
6167 You can obtain this information using @code{guix download}
6168 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
6171 @item @code{file-name} (default: @code{#f})
6172 The file name under which the source code should be saved. When this is
6173 @code{#f}, a sensible default value will be used in most cases. In case
6174 the source is fetched from a URL, the file name from the URL will be
6175 used. For version control checkouts, it is recommended to provide the
6176 file name explicitly because the default is not very descriptive.
6178 @item @code{patches} (default: @code{'()})
6179 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
6180 file-like objects}) pointing to patches to be applied to the source.
6182 This list of patches must be unconditional. In particular, it cannot
6183 depend on the value of @code{%current-system} or
6184 @code{%current-target-system}.
6186 @item @code{snippet} (default: @code{#f})
6187 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
6188 in the source directory. This is a convenient way to modify the source,
6189 sometimes more convenient than a patch.
6191 @item @code{patch-flags} (default: @code{'("-p1")})
6192 A list of command-line flags that should be passed to the @code{patch}
6195 @item @code{patch-inputs} (default: @code{#f})
6196 Input packages or derivations to the patching process. When this is
6197 @code{#f}, the usual set of inputs necessary for patching are provided,
6198 such as GNU@tie{}Patch.
6200 @item @code{modules} (default: @code{'()})
6201 A list of Guile modules that should be loaded during the patching
6202 process and while running the code in the @code{snippet} field.
6204 @item @code{patch-guile} (default: @code{#f})
6205 The Guile package that should be used in the patching process. When
6206 this is @code{#f}, a sensible default is used.
6210 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
6211 Construct a content hash object for the given @var{algorithm}, and with
6212 @var{value} as its hash value. When @var{algorithm} is omitted, assume
6213 it is @code{sha256}.
6215 @var{value} can be a literal string, in which case it is base32-decoded,
6216 or it can be a bytevector.
6218 The following forms are all equivalent:
6221 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
6222 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
6224 (content-hash (base32
6225 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
6226 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
6230 Technically, @code{content-hash} is currently implemented as a macro.
6231 It performs sanity checks at macro-expansion time, when possible, such
6232 as ensuring that @var{value} has the right size for @var{algorithm}.
6236 @section Build Systems
6238 @cindex build system
6239 Each package definition specifies a @dfn{build system} and arguments for
6240 that build system (@pxref{Defining Packages}). This @code{build-system}
6241 field represents the build procedure of the package, as well as implicit
6242 dependencies of that build procedure.
6244 Build systems are @code{<build-system>} objects. The interface to
6245 create and manipulate them is provided by the @code{(guix build-system)}
6246 module, and actual build systems are exported by specific modules.
6248 @cindex bag (low-level package representation)
6249 Under the hood, build systems first compile package objects to
6250 @dfn{bags}. A @dfn{bag} is like a package, but with less
6251 ornamentation---in other words, a bag is a lower-level representation of
6252 a package, which includes all the inputs of that package, including some
6253 that were implicitly added by the build system. This intermediate
6254 representation is then compiled to a derivation (@pxref{Derivations}).
6256 Build systems accept an optional list of @dfn{arguments}. In package
6257 definitions, these are passed @i{via} the @code{arguments} field
6258 (@pxref{Defining Packages}). They are typically keyword arguments
6259 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
6260 Guile Reference Manual}). The value of these arguments is usually
6261 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
6262 by the daemon (@pxref{Derivations}).
6264 The main build system is @code{gnu-build-system}, which implements the
6265 standard build procedure for GNU and many other packages. It
6266 is provided by the @code{(guix build-system gnu)} module.
6268 @defvr {Scheme Variable} gnu-build-system
6269 @code{gnu-build-system} represents the GNU Build System, and variants
6270 thereof (@pxref{Configuration, configuration and makefile conventions,,
6271 standards, GNU Coding Standards}).
6273 @cindex build phases
6274 In a nutshell, packages using it are configured, built, and installed with
6275 the usual @code{./configure && make && make check && make install}
6276 command sequence. In practice, a few additional steps are often needed.
6277 All these steps are split up in separate @dfn{phases},
6278 notably@footnote{Please see the @code{(guix build gnu-build-system)}
6279 modules for more details about the build phases.}:
6283 Unpack the source tarball, and change the current directory to the
6284 extracted source tree. If the source is actually a directory, copy it
6285 to the build tree, and enter that directory.
6287 @item patch-source-shebangs
6288 Patch shebangs encountered in source files so they refer to the right
6289 store file names. For instance, this changes @code{#!/bin/sh} to
6290 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
6293 Run the @file{configure} script with a number of default options, such
6294 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
6295 by the @code{#:configure-flags} argument.
6298 Run @code{make} with the list of flags specified with
6299 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
6300 (the default), build with @code{make -j}.
6303 Run @code{make check}, or some other target specified with
6304 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
6305 @code{#:parallel-tests?} argument is true (the default), run @code{make
6309 Run @code{make install} with the flags listed in @code{#:make-flags}.
6311 @item patch-shebangs
6312 Patch shebangs on the installed executable files.
6315 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
6316 is false), copying them to the @code{debug} output when available
6317 (@pxref{Installing Debugging Files}).
6320 @vindex %standard-phases
6321 The build-side module @code{(guix build gnu-build-system)} defines
6322 @code{%standard-phases} as the default list of build phases.
6323 @code{%standard-phases} is a list of symbol/procedure pairs, where the
6324 procedure implements the actual phase.
6326 The list of phases used for a particular package can be changed with the
6327 @code{#:phases} parameter. For instance, passing:
6330 #:phases (modify-phases %standard-phases (delete 'configure))
6333 means that all the phases described above will be used, except the
6334 @code{configure} phase.
6336 In addition, this build system ensures that the ``standard'' environment
6337 for GNU packages is available. This includes tools such as GCC, libc,
6338 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
6339 build-system gnu)} module for a complete list). We call these the
6340 @dfn{implicit inputs} of a package, because package definitions do not
6341 have to mention them.
6344 Other @code{<build-system>} objects are defined to support other
6345 conventions and tools used by free software packages. They inherit most
6346 of @code{gnu-build-system}, and differ mainly in the set of inputs
6347 implicitly added to the build process, and in the list of phases
6348 executed. Some of these build systems are listed below.
6350 @defvr {Scheme Variable} ant-build-system
6351 This variable is exported by @code{(guix build-system ant)}. It
6352 implements the build procedure for Java packages that can be built with
6353 @url{https://ant.apache.org/, Ant build tool}.
6355 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
6356 provided by the @code{icedtea} package to the set of inputs. Different
6357 packages can be specified with the @code{#:ant} and @code{#:jdk}
6358 parameters, respectively.
6360 When the original package does not provide a suitable Ant build file,
6361 the parameter @code{#:jar-name} can be used to generate a minimal Ant
6362 build file @file{build.xml} with tasks to build the specified jar
6363 archive. In this case the parameter @code{#:source-dir} can be used to
6364 specify the source sub-directory, defaulting to ``src''.
6366 The @code{#:main-class} parameter can be used with the minimal ant
6367 buildfile to specify the main class of the resulting jar. This makes the
6368 jar file executable. The @code{#:test-include} parameter can be used to
6369 specify the list of junit tests to run. It defaults to
6370 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
6371 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
6372 because abstract classes cannot be run as tests.
6374 The parameter @code{#:build-target} can be used to specify the Ant task
6375 that should be run during the @code{build} phase. By default the
6376 ``jar'' task will be run.
6380 @defvr {Scheme Variable} android-ndk-build-system
6381 @cindex Android distribution
6382 @cindex Android NDK build system
6383 This variable is exported by @code{(guix build-system android-ndk)}. It
6384 implements a build procedure for Android NDK (native development kit)
6385 packages using a Guix-specific build process.
6387 The build system assumes that packages install their public interface
6388 (header) files to the subdirectory @file{include} of the @code{out} output and
6389 their libraries to the subdirectory @file{lib} the @code{out} output.
6391 It's also assumed that the union of all the dependencies of a package
6392 has no conflicting files.
6394 For the time being, cross-compilation is not supported - so right now
6395 the libraries and header files are assumed to be host tools.
6399 @defvr {Scheme Variable} asdf-build-system/source
6400 @defvrx {Scheme Variable} asdf-build-system/sbcl
6401 @defvrx {Scheme Variable} asdf-build-system/ecl
6403 These variables, exported by @code{(guix build-system asdf)}, implement
6404 build procedures for Common Lisp packages using
6405 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
6406 definition facility for Common Lisp programs and libraries.
6408 The @code{asdf-build-system/source} system installs the packages in
6409 source form, and can be loaded using any common lisp implementation, via
6410 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
6411 systems in the format which a particular implementation understands.
6412 These build systems can also be used to produce executable programs, or
6413 lisp images which contain a set of packages pre-loaded.
6415 The build system uses naming conventions. For binary packages, the
6416 package name should be prefixed with the lisp implementation, such as
6417 @code{sbcl-} for @code{asdf-build-system/sbcl}.
6419 Additionally, the corresponding source package should be labeled using
6420 the same convention as python packages (see @ref{Python Modules}), using
6421 the @code{cl-} prefix.
6423 For binary packages, each system should be defined as a Guix package.
6424 If one package @code{origin} contains several systems, package variants
6425 can be created in order to build all the systems. Source packages,
6426 which use @code{asdf-build-system/source}, may contain several systems.
6428 In order to create executable programs and images, the build-side
6429 procedures @code{build-program} and @code{build-image} can be used.
6430 They should be called in a build phase after the @code{create-symlinks}
6431 phase, so that the system which was just built can be used within the
6432 resulting image. @code{build-program} requires a list of Common Lisp
6433 expressions to be passed as the @code{#:entry-program} argument.
6435 If the system is not defined within its own @file{.asd} file of the same
6436 name, then the @code{#:asd-file} parameter should be used to specify
6437 which file the system is defined in. Furthermore, if the package
6438 defines a system for its tests in a separate file, it will be loaded
6439 before the tests are run if it is specified by the
6440 @code{#:test-asd-file} parameter. If it is not set, the files
6441 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
6442 and @code{test.asd} will be tried if they exist.
6444 If for some reason the package must be named in a different way than the
6445 naming conventions suggest, the @code{#:asd-system-name} parameter can
6446 be used to specify the name of the system.
6450 @defvr {Scheme Variable} cargo-build-system
6451 @cindex Rust programming language
6452 @cindex Cargo (Rust build system)
6453 This variable is exported by @code{(guix build-system cargo)}. It
6454 supports builds of packages using Cargo, the build tool of the
6455 @uref{https://www.rust-lang.org, Rust programming language}.
6457 It adds @code{rustc} and @code{cargo} to the set of inputs.
6458 A different Rust package can be specified with the @code{#:rust} parameter.
6460 Regular cargo dependencies should be added to the package definition via the
6461 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
6462 spec can be a package or a source definition. Note that the spec must
6463 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
6464 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
6465 should be added to the package definition via the
6466 @code{#:cargo-development-inputs} parameter.
6468 In its @code{configure} phase, this build system will make any source inputs
6469 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
6470 parameters available to cargo. It will also remove an included
6471 @code{Cargo.lock} file to be recreated by @code{cargo} during the
6472 @code{build} phase. The @code{install} phase installs any crate the binaries
6473 if they are defined by the crate.
6477 @defvr {Scheme Variable} copy-build-system
6478 This variable is exported by @code{(guix build-system copy)}. It
6479 supports builds of simple packages that don't require much compiling,
6480 mostly just moving files around.
6482 It adds much of the @code{gnu-build-system} packages to the set of
6483 inputs. Because of this, the @code{copy-build-system} does not require
6484 all the boilerplate code often needed for the
6485 @code{trivial-build-system}.
6487 To further simplify the file installation process, an
6488 @code{#:install-plan} argument is exposed to let the packager specify
6489 which files go where. The install plan is a list of @code{(@var{source}
6490 @var{target} [@var{filters}])}. @var{filters} are optional.
6493 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
6495 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
6496 @item Otherwise install @var{source} as @var{target}.
6499 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
6500 the trailing slash of @var{target} is implied with the same meaning
6503 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
6504 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
6505 @code{#:exclude-regexp}, only select files are installed depending on
6506 the filters. Each filters is specified by a list of strings.
6508 @item With @code{#:include}, install all the files which the path suffix matches
6509 at least one of the elements in the given list.
6510 @item With @code{#:include-regexp}, install all the files which the
6511 subpaths match at least one of the regular expressions in the given
6513 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
6514 are the complement of their inclusion counterpart. Without @code{#:include} flags,
6515 install all files but those matching the exclusion filters.
6516 If both inclusions and exclusions are specified, the exclusions are done
6517 on top of the inclusions.
6520 In all cases, the paths relative to @var{source} are preserved within
6527 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
6528 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
6529 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
6530 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
6531 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
6532 @file{share/my-app/sub/file}.
6533 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
6534 @file{share/my-app/file}.
6539 @cindex Clojure (programming language)
6540 @cindex simple Clojure build system
6541 @defvr {Scheme Variable} clojure-build-system
6542 This variable is exported by @code{(guix build-system clojure)}. It implements
6543 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
6544 using plain old @code{compile} in Clojure. Cross-compilation is not supported
6547 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
6548 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
6549 @code{#:zip} parameters, respectively.
6551 A list of source directories, test directories and jar names can be specified
6552 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
6553 parameters, respectively. Compile directory and main class can be specified
6554 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
6555 Other parameters are documented below.
6557 This build system is an extension of @code{ant-build-system}, but with the
6558 following phases changed:
6563 This phase calls @code{compile} in Clojure to compile source files and runs
6564 @command{jar} to create jars from both source files and compiled files
6565 according to the include list and exclude list specified in
6566 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
6567 has priority over the include list. These lists consist of symbols
6568 representing Clojure libraries or the special keyword @code{#:all} representing
6569 all Clojure libraries found under the source directories. The parameter
6570 @code{#:omit-source?} decides if source should be included into the jars.
6573 This phase runs tests according to the include list and exclude list specified
6574 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
6575 meanings are analogous to that of @code{#:aot-include} and
6576 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
6577 stands for all Clojure libraries found under the test directories. The
6578 parameter @code{#:tests?} decides if tests should be run.
6581 This phase installs all jars built previously.
6584 Apart from the above, this build system also contains an additional phase:
6589 This phase installs all top-level files with base name matching
6590 @code{%doc-regex}. A different regex can be specified with the
6591 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
6592 directories specified in @code{#:doc-dirs} are installed as well.
6596 @defvr {Scheme Variable} cmake-build-system
6597 This variable is exported by @code{(guix build-system cmake)}. It
6598 implements the build procedure for packages using the
6599 @url{https://www.cmake.org, CMake build tool}.
6601 It automatically adds the @code{cmake} package to the set of inputs.
6602 Which package is used can be specified with the @code{#:cmake}
6605 The @code{#:configure-flags} parameter is taken as a list of flags
6606 passed to the @command{cmake} command. The @code{#:build-type}
6607 parameter specifies in abstract terms the flags passed to the compiler;
6608 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
6609 debugging information''), which roughly means that code is compiled with
6610 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
6613 @defvr {Scheme Variable} dune-build-system
6614 This variable is exported by @code{(guix build-system dune)}. It
6615 supports builds of packages using @uref{https://dune.build/, Dune}, a build
6616 tool for the OCaml programming language. It is implemented as an extension
6617 of the @code{ocaml-build-system} which is described below. As such, the
6618 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
6621 It automatically adds the @code{dune} package to the set of inputs.
6622 Which package is used can be specified with the @code{#:dune}
6625 There is no @code{configure} phase because dune packages typically don't
6626 need to be configured. The @code{#:build-flags} parameter is taken as a
6627 list of flags passed to the @code{dune} command during the build.
6629 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
6630 command instead of the more recent @code{dune} command while building
6631 a package. Its default value is @code{#f}.
6633 The @code{#:package} parameter can be passed to specify a package name, which
6634 is useful when a package contains multiple packages and you want to build
6635 only one of them. This is equivalent to passing the @code{-p} argument to
6639 @defvr {Scheme Variable} go-build-system
6640 This variable is exported by @code{(guix build-system go)}. It
6641 implements a build procedure for Go packages using the standard
6642 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
6643 Go build mechanisms}.
6645 The user is expected to provide a value for the key @code{#:import-path}
6646 and, in some cases, @code{#:unpack-path}. The
6647 @url{https://golang.org/doc/code.html#ImportPaths, import path}
6648 corresponds to the file system path expected by the package's build
6649 scripts and any referring packages, and provides a unique way to
6650 refer to a Go package. It is typically based on a combination of the
6651 package source code's remote URI and file system hierarchy structure. In
6652 some cases, you will need to unpack the package's source code to a
6653 different directory structure than the one indicated by the import path,
6654 and @code{#:unpack-path} should be used in such cases.
6656 Packages that provide Go libraries should install their source code into
6657 the built output. The key @code{#:install-source?}, which defaults to
6658 @code{#t}, controls whether or not the source code is installed. It can
6659 be set to @code{#f} for packages that only provide executable files.
6662 @defvr {Scheme Variable} glib-or-gtk-build-system
6663 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
6664 is intended for use with packages making use of GLib or GTK+.
6666 This build system adds the following two phases to the ones defined by
6667 @code{gnu-build-system}:
6670 @item glib-or-gtk-wrap
6671 The phase @code{glib-or-gtk-wrap} ensures that programs in
6672 @file{bin/} are able to find GLib ``schemas'' and
6673 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
6674 modules}. This is achieved by wrapping the programs in launch scripts
6675 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
6676 environment variables.
6678 It is possible to exclude specific package outputs from that wrapping
6679 process by listing their names in the
6680 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
6681 when an output is known not to contain any GLib or GTK+ binaries, and
6682 where wrapping would gratuitously add a dependency of that output on
6685 @item glib-or-gtk-compile-schemas
6686 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
6687 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
6688 GSettings schemas} of GLib are compiled. Compilation is performed by the
6689 @command{glib-compile-schemas} program. It is provided by the package
6690 @code{glib:bin} which is automatically imported by the build system.
6691 The @code{glib} package providing @command{glib-compile-schemas} can be
6692 specified with the @code{#:glib} parameter.
6695 Both phases are executed after the @code{install} phase.
6698 @defvr {Scheme Variable} guile-build-system
6699 This build system is for Guile packages that consist exclusively of Scheme
6700 code and that are so lean that they don't even have a makefile, let alone a
6701 @file{configure} script. It compiles Scheme code using @command{guild
6702 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6703 installs the @file{.scm} and @file{.go} files in the right place. It also
6704 installs documentation.
6706 This build system supports cross-compilation by using the
6707 @option{--target} option of @samp{guild compile}.
6709 Packages built with @code{guile-build-system} must provide a Guile package in
6710 their @code{native-inputs} field.
6713 @defvr {Scheme Variable} julia-build-system
6714 This variable is exported by @code{(guix build-system julia)}. It
6715 implements the build procedure used by @uref{https://julialang.org/,
6716 julia} packages, which essentially is similar to running @samp{julia -e
6717 'using Pkg; Pkg.add(package)'} in an environment where
6718 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
6719 Tests are run not run.
6721 Julia packages require the source @code{file-name} to be the real name of the
6722 package, correctly capitalized.
6724 For packages requiring shared library dependencies, you may need to write the
6725 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
6726 variable = /gnu/store/library.so} for each dependency, plus a void function
6727 @code{check_deps() = nothing}.
6729 Some older packages that aren't using @file{Package.toml} yet, will require
6730 this file to be created, too. The function @code{julia-create-package-toml}
6731 helps creating the file. You need to pass the outputs and the source of the
6732 package, it's name (the same as the @code{file-name} parameter), the package
6733 uuid, the package version, and a list of dependencies specified by their name
6737 @defvr {Scheme Variable} minify-build-system
6738 This variable is exported by @code{(guix build-system minify)}. It
6739 implements a minification procedure for simple JavaScript packages.
6741 It adds @code{uglify-js} to the set of inputs and uses it to compress
6742 all JavaScript files in the @file{src} directory. A different minifier
6743 package can be specified with the @code{#:uglify-js} parameter, but it
6744 is expected that the package writes the minified code to the standard
6747 When the input JavaScript files are not all located in the @file{src}
6748 directory, the parameter @code{#:javascript-files} can be used to
6749 specify a list of file names to feed to the minifier.
6752 @defvr {Scheme Variable} ocaml-build-system
6753 This variable is exported by @code{(guix build-system ocaml)}. It implements
6754 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6755 of choosing the correct set of commands to run for each package. OCaml
6756 packages can expect many different commands to be run. This build system will
6759 When the package has a @file{setup.ml} file present at the top-level, it will
6760 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6761 @code{ocaml setup.ml -install}. The build system will assume that this file
6762 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6763 care of setting the prefix and enabling tests if they are not disabled. You
6764 can pass configure and build flags with the @code{#:configure-flags} and
6765 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6766 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6767 bypass this system in the build and install phases.
6769 When the package has a @file{configure} file, it is assumed that it is a
6770 hand-made configure script that requires a different argument format than
6771 in the @code{gnu-build-system}. You can add more flags with the
6772 @code{#:configure-flags} key.
6774 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6775 @code{#t}), it will be used and more flags can be passed to the build and
6776 install phases with the @code{#:make-flags} key.
6778 Finally, some packages do not have these files and use a somewhat standard
6779 location for its build system. In that case, the build system will run
6780 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6781 providing the path to the required findlib module. Additional flags can
6782 be passed via the @code{#:build-flags} key. Install is taken care of by
6783 @command{opam-installer}. In this case, the @code{opam} package must
6784 be added to the @code{native-inputs} field of the package definition.
6786 Note that most OCaml packages assume they will be installed in the same
6787 directory as OCaml, which is not what we want in guix. In particular, they
6788 will install @file{.so} files in their module's directory, which is usually
6789 fine because it is in the OCaml compiler directory. In guix though, these
6790 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
6791 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6792 @file{.so} libraries should be installed.
6795 @defvr {Scheme Variable} python-build-system
6796 This variable is exported by @code{(guix build-system python)}. It
6797 implements the more or less standard build procedure used by Python
6798 packages, which consists in running @code{python setup.py build} and
6799 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6801 For packages that install stand-alone Python programs under @code{bin/},
6802 it takes care of wrapping these programs so that their @env{PYTHONPATH}
6803 environment variable points to all the Python libraries they depend on.
6805 Which Python package is used to perform the build can be specified with
6806 the @code{#:python} parameter. This is a useful way to force a package
6807 to be built for a specific version of the Python interpreter, which
6808 might be necessary if the package is only compatible with a single
6809 interpreter version.
6811 By default guix calls @code{setup.py} under control of
6812 @code{setuptools}, much like @command{pip} does. Some packages are not
6813 compatible with setuptools (and pip), thus you can disable this by
6814 setting the @code{#:use-setuptools?} parameter to @code{#f}.
6817 @defvr {Scheme Variable} perl-build-system
6818 This variable is exported by @code{(guix build-system perl)}. It
6819 implements the standard build procedure for Perl packages, which either
6820 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6821 followed by @code{Build} and @code{Build install}; or in running
6822 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6823 @code{make} and @code{make install}, depending on which of
6824 @code{Build.PL} or @code{Makefile.PL} is present in the package
6825 distribution. Preference is given to the former if both @code{Build.PL}
6826 and @code{Makefile.PL} exist in the package distribution. This
6827 preference can be reversed by specifying @code{#t} for the
6828 @code{#:make-maker?} parameter.
6830 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6831 passes flags specified by the @code{#:make-maker-flags} or
6832 @code{#:module-build-flags} parameter, respectively.
6834 Which Perl package is used can be specified with @code{#:perl}.
6837 @defvr {Scheme Variable} qt-build-system
6838 This variable is exported by @code{(guix build-system qt)}. It
6839 is intended for use with applications using Qt or KDE.
6841 This build system adds the following two phases to the ones defined by
6842 @code{cmake-build-system}:
6846 The phase @code{check-setup} prepares the environment for running
6847 the checks as commonly used by Qt test programs.
6848 For now this only sets some environment variables:
6849 @code{QT_QPA_PLATFORM=offscreen},
6850 @code{DBUS_FATAL_WARNINGS=0} and
6851 @code{CTEST_OUTPUT_ON_FAILURE=1}.
6853 This phase is added before the @code{check} phase.
6854 It's a separate phase to ease adjusting if necessary.
6857 The phase @code{qt-wrap}
6858 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
6859 and output. In case some path is found, all programs in the output's
6860 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
6861 are wrapped in scripts defining the necessary environment variables.
6863 It is possible to exclude specific package outputs from that wrapping process
6864 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
6865 This is useful when an output is known not to contain any Qt binaries, and
6866 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
6869 This phase is added after the @code{install} phase.
6873 @defvr {Scheme Variable} r-build-system
6874 This variable is exported by @code{(guix build-system r)}. It
6875 implements the build procedure used by @uref{https://r-project.org, R}
6876 packages, which essentially is little more than running @samp{R CMD
6877 INSTALL --library=/gnu/store/@dots{}} in an environment where
6878 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
6879 run after installation using the R function
6880 @code{tools::testInstalledPackage}.
6883 @defvr {Scheme Variable} rakudo-build-system
6884 This variable is exported by @code{(guix build-system rakudo)}. It
6885 implements the build procedure used by @uref{https://rakudo.org/,
6886 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6887 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6888 installs the binaries, library files and the resources, as well as wrap
6889 the files under the @code{bin/} directory. Tests can be skipped by
6890 passing @code{#f} to the @code{tests?} parameter.
6892 Which rakudo package is used can be specified with @code{rakudo}.
6893 Which perl6-tap-harness package used for the tests can be specified with
6894 @code{#:prove6} or removed by passing @code{#f} to the
6895 @code{with-prove6?} parameter.
6896 Which perl6-zef package used for tests and installing can be specified
6897 with @code{#:zef} or removed by passing @code{#f} to the
6898 @code{with-zef?} parameter.
6901 @defvr {Scheme Variable} texlive-build-system
6902 This variable is exported by @code{(guix build-system texlive)}. It is
6903 used to build TeX packages in batch mode with a specified engine. The
6904 build system sets the @env{TEXINPUTS} variable to find all TeX source
6905 files in the inputs.
6907 By default it runs @code{luatex} on all files ending on @code{ins}. A
6908 different engine and format can be specified with the
6909 @code{#:tex-format} argument. Different build targets can be specified
6910 with the @code{#:build-targets} argument, which expects a list of file
6911 names. The build system adds only @code{texlive-bin} and
6912 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6913 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6914 and @code{#:texlive-latex-base}, respectively.
6916 The @code{#:tex-directory} parameter tells the build system where to
6917 install the built files under the texmf tree.
6920 @defvr {Scheme Variable} ruby-build-system
6921 This variable is exported by @code{(guix build-system ruby)}. It
6922 implements the RubyGems build procedure used by Ruby packages, which
6923 involves running @code{gem build} followed by @code{gem install}.
6925 The @code{source} field of a package that uses this build system
6926 typically references a gem archive, since this is the format that Ruby
6927 developers use when releasing their software. The build system unpacks
6928 the gem archive, potentially patches the source, runs the test suite,
6929 repackages the gem, and installs it. Additionally, directories and
6930 tarballs may be referenced to allow building unreleased gems from Git or
6931 a traditional source release tarball.
6933 Which Ruby package is used can be specified with the @code{#:ruby}
6934 parameter. A list of additional flags to be passed to the @command{gem}
6935 command can be specified with the @code{#:gem-flags} parameter.
6938 @defvr {Scheme Variable} waf-build-system
6939 This variable is exported by @code{(guix build-system waf)}. It
6940 implements a build procedure around the @code{waf} script. The common
6941 phases---@code{configure}, @code{build}, and @code{install}---are
6942 implemented by passing their names as arguments to the @code{waf}
6945 The @code{waf} script is executed by the Python interpreter. Which
6946 Python package is used to run the script can be specified with the
6947 @code{#:python} parameter.
6950 @defvr {Scheme Variable} scons-build-system
6951 This variable is exported by @code{(guix build-system scons)}. It
6952 implements the build procedure used by the SCons software construction
6953 tool. This build system runs @code{scons} to build the package,
6954 @code{scons test} to run tests, and then @code{scons install} to install
6957 Additional flags to be passed to @code{scons} can be specified with the
6958 @code{#:scons-flags} parameter. The default build and install targets
6959 can be overridden with @code{#:build-targets} and
6960 @code{#:install-targets} respectively. The version of Python used to
6961 run SCons can be specified by selecting the appropriate SCons package
6962 with the @code{#:scons} parameter.
6965 @defvr {Scheme Variable} haskell-build-system
6966 This variable is exported by @code{(guix build-system haskell)}. It
6967 implements the Cabal build procedure used by Haskell packages, which
6968 involves running @code{runhaskell Setup.hs configure
6969 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6970 Instead of installing the package by running @code{runhaskell Setup.hs
6971 install}, to avoid trying to register libraries in the read-only
6972 compiler store directory, the build system uses @code{runhaskell
6973 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6974 addition, the build system generates the package documentation by
6975 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6976 is passed. Optional Haddock parameters can be passed with the help of
6977 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6978 not found, the build system looks for @code{Setup.lhs} instead.
6980 Which Haskell compiler is used can be specified with the @code{#:haskell}
6981 parameter which defaults to @code{ghc}.
6984 @defvr {Scheme Variable} dub-build-system
6985 This variable is exported by @code{(guix build-system dub)}. It
6986 implements the Dub build procedure used by D packages, which
6987 involves running @code{dub build} and @code{dub run}.
6988 Installation is done by copying the files manually.
6990 Which D compiler is used can be specified with the @code{#:ldc}
6991 parameter which defaults to @code{ldc}.
6994 @defvr {Scheme Variable} emacs-build-system
6995 This variable is exported by @code{(guix build-system emacs)}. It
6996 implements an installation procedure similar to the packaging system
6997 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6999 It first creates the @code{@code{package}-autoloads.el} file, then it
7000 byte compiles all Emacs Lisp files. Differently from the Emacs
7001 packaging system, the Info documentation files are moved to the standard
7002 documentation directory and the @file{dir} file is deleted. The Elisp
7003 package files are installed directly under @file{share/emacs/site-lisp}.
7006 @defvr {Scheme Variable} font-build-system
7007 This variable is exported by @code{(guix build-system font)}. It
7008 implements an installation procedure for font packages where upstream
7009 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
7010 need to be copied into place. It copies font files to standard
7011 locations in the output directory.
7014 @defvr {Scheme Variable} meson-build-system
7015 This variable is exported by @code{(guix build-system meson)}. It
7016 implements the build procedure for packages that use
7017 @url{https://mesonbuild.com, Meson} as their build system.
7019 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
7020 of inputs, and they can be changed with the parameters @code{#:meson}
7021 and @code{#:ninja} if needed. The default Meson is
7022 @code{meson-for-build}, which is special because it doesn't clear the
7023 @code{RUNPATH} of binaries and libraries when they are installed.
7025 This build system is an extension of @code{gnu-build-system}, but with the
7026 following phases changed to some specific for Meson:
7031 The phase runs @code{meson} with the flags specified in
7032 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
7033 @code{debugoptimized} unless something else is specified in
7034 @code{#:build-type}.
7037 The phase runs @code{ninja} to build the package in parallel by default, but
7038 this can be changed with @code{#:parallel-build?}.
7041 The phase runs @code{ninja} with the target specified in @code{#:test-target},
7042 which is @code{"test"} by default.
7045 The phase runs @code{ninja install} and can not be changed.
7048 Apart from that, the build system also adds the following phases:
7053 This phase ensures that all binaries can find the libraries they need.
7054 It searches for required libraries in subdirectories of the package being
7055 built, and adds those to @code{RUNPATH} where needed. It also removes
7056 references to libraries left over from the build phase by
7057 @code{meson-for-build}, such as test dependencies, that aren't actually
7058 required for the program to run.
7060 @item glib-or-gtk-wrap
7061 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
7062 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
7064 @item glib-or-gtk-compile-schemas
7065 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
7066 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
7070 @defvr {Scheme Variable} linux-module-build-system
7071 @code{linux-module-build-system} allows building Linux kernel modules.
7073 @cindex build phases
7074 This build system is an extension of @code{gnu-build-system}, but with the
7075 following phases changed:
7080 This phase configures the environment so that the Linux kernel's Makefile
7081 can be used to build the external kernel module.
7084 This phase uses the Linux kernel's Makefile in order to build the external
7088 This phase uses the Linux kernel's Makefile in order to install the external
7092 It is possible and useful to specify the Linux kernel to use for building
7093 the module (in the @code{arguments} form of a package using the
7094 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
7097 @defvr {Scheme Variable} node-build-system
7098 This variable is exported by @code{(guix build-system node)}. It
7099 implements the build procedure used by @uref{https://nodejs.org,
7100 Node.js}, which implements an approximation of the @code{npm install}
7101 command, followed by an @code{npm test} command.
7103 Which Node.js package is used to interpret the @code{npm} commands can
7104 be specified with the @code{#:node} parameter which defaults to
7108 Lastly, for packages that do not need anything as sophisticated, a
7109 ``trivial'' build system is provided. It is trivial in the sense that
7110 it provides basically no support: it does not pull any implicit inputs,
7111 and does not have a notion of build phases.
7113 @defvr {Scheme Variable} trivial-build-system
7114 This variable is exported by @code{(guix build-system trivial)}.
7116 This build system requires a @code{#:builder} argument. This argument
7117 must be a Scheme expression that builds the package output(s)---as
7118 with @code{build-expression->derivation} (@pxref{Derivations,
7119 @code{build-expression->derivation}}).
7129 Conceptually, the @dfn{store} is the place where derivations that have
7130 been built successfully are stored---by default, @file{/gnu/store}.
7131 Sub-directories in the store are referred to as @dfn{store items} or
7132 sometimes @dfn{store paths}. The store has an associated database that
7133 contains information such as the store paths referred to by each store
7134 path, and the list of @emph{valid} store items---results of successful
7135 builds. This database resides in @file{@var{localstatedir}/guix/db},
7136 where @var{localstatedir} is the state directory specified @i{via}
7137 @option{--localstatedir} at configure time, usually @file{/var}.
7139 The store is @emph{always} accessed by the daemon on behalf of its clients
7140 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
7141 connect to the daemon over a Unix-domain socket, send requests to it,
7142 and read the result---these are remote procedure calls, or RPCs.
7145 Users must @emph{never} modify files under @file{/gnu/store} directly.
7146 This would lead to inconsistencies and break the immutability
7147 assumptions of Guix's functional model (@pxref{Introduction}).
7149 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
7150 how to check the integrity of the store and attempt recovery from
7151 accidental modifications.
7154 The @code{(guix store)} module provides procedures to connect to the
7155 daemon, and to perform RPCs. These are described below. By default,
7156 @code{open-connection}, and thus all the @command{guix} commands,
7157 connect to the local daemon or to the URI specified by the
7158 @env{GUIX_DAEMON_SOCKET} environment variable.
7160 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
7161 When set, the value of this variable should be a file name or a URI
7162 designating the daemon endpoint. When it is a file name, it denotes a
7163 Unix-domain socket to connect to. In addition to file names, the
7164 supported URI schemes are:
7169 These are for Unix-domain sockets.
7170 @code{file:///var/guix/daemon-socket/socket} is equivalent to
7171 @file{/var/guix/daemon-socket/socket}.
7174 @cindex daemon, remote access
7175 @cindex remote access to the daemon
7176 @cindex daemon, cluster setup
7177 @cindex clusters, daemon setup
7178 These URIs denote connections over TCP/IP, without encryption nor
7179 authentication of the remote host. The URI must specify the host name
7180 and optionally a port number (by default port 44146 is used):
7183 guix://master.guix.example.org:1234
7186 This setup is suitable on local networks, such as clusters, where only
7187 trusted nodes may connect to the build daemon at
7188 @code{master.guix.example.org}.
7190 The @option{--listen} option of @command{guix-daemon} can be used to
7191 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
7192 @option{--listen}}).
7195 @cindex SSH access to build daemons
7196 These URIs allow you to connect to a remote daemon over SSH. This
7197 feature requires Guile-SSH (@pxref{Requirements}) and a working
7198 @command{guile} binary in @env{PATH} on the destination machine. It
7199 supports public key and GSSAPI authentication. A typical URL might look
7203 ssh://charlie@@guix.example.org:22
7206 As for @command{guix copy}, the usual OpenSSH client configuration files
7207 are honored (@pxref{Invoking guix copy}).
7210 Additional URI schemes may be supported in the future.
7212 @c XXX: Remove this note when the protocol incurs fewer round trips
7213 @c and when (guix derivations) no longer relies on file system access.
7215 The ability to connect to remote build daemons is considered
7216 experimental as of @value{VERSION}. Please get in touch with us to
7217 share any problems or suggestions you may have (@pxref{Contributing}).
7221 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
7222 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
7223 @var{reserve-space?} is true, instruct it to reserve a little bit of
7224 extra space on the file system so that the garbage collector can still
7225 operate should the disk become full. Return a server object.
7227 @var{file} defaults to @code{%default-socket-path}, which is the normal
7228 location given the options that were passed to @command{configure}.
7231 @deffn {Scheme Procedure} close-connection @var{server}
7232 Close the connection to @var{server}.
7235 @defvr {Scheme Variable} current-build-output-port
7236 This variable is bound to a SRFI-39 parameter, which refers to the port
7237 where build and error logs sent by the daemon should be written.
7240 Procedures that make RPCs all take a server object as their first
7243 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
7244 @cindex invalid store items
7245 Return @code{#t} when @var{path} designates a valid store item and
7246 @code{#f} otherwise (an invalid item may exist on disk but still be
7247 invalid, for instance because it is the result of an aborted or failed
7250 A @code{&store-protocol-error} condition is raised if @var{path} is not
7251 prefixed by the store directory (@file{/gnu/store}).
7254 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
7255 Add @var{text} under file @var{name} in the store, and return its store
7256 path. @var{references} is the list of store paths referred to by the
7257 resulting store path.
7260 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
7262 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
7263 file names, or derivation/output pairs, using the specified
7264 @var{mode}---@code{(build-mode normal)} by default.
7267 Note that the @code{(guix monads)} module provides a monad as well as
7268 monadic versions of the above procedures, with the goal of making it
7269 more convenient to work with code that accesses the store (@pxref{The
7273 @i{This section is currently incomplete.}
7276 @section Derivations
7279 Low-level build actions and the environment in which they are performed
7280 are represented by @dfn{derivations}. A derivation contains the
7281 following pieces of information:
7285 The outputs of the derivation---derivations produce at least one file or
7286 directory in the store, but may produce more.
7289 @cindex build-time dependencies
7290 @cindex dependencies, build-time
7291 The inputs of the derivations---i.e., its build-time dependencies---which may
7292 be other derivations or plain files in the store (patches, build scripts,
7296 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
7299 The file name of a build script in the store, along with the arguments
7303 A list of environment variables to be defined.
7307 @cindex derivation path
7308 Derivations allow clients of the daemon to communicate build actions to
7309 the store. They exist in two forms: as an in-memory representation,
7310 both on the client- and daemon-side, and as files in the store whose
7311 name end in @file{.drv}---these files are referred to as @dfn{derivation
7312 paths}. Derivations paths can be passed to the @code{build-derivations}
7313 procedure to perform the build actions they prescribe (@pxref{The
7316 @cindex fixed-output derivations
7317 Operations such as file downloads and version-control checkouts for
7318 which the expected content hash is known in advance are modeled as
7319 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
7320 of a fixed-output derivation are independent of its inputs---e.g., a
7321 source code download produces the same result regardless of the download
7322 method and tools being used.
7325 @cindex run-time dependencies
7326 @cindex dependencies, run-time
7327 The outputs of derivations---i.e., the build results---have a set of
7328 @dfn{references}, as reported by the @code{references} RPC or the
7329 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
7330 are the set of run-time dependencies of the build results. References are a
7331 subset of the inputs of the derivation; this subset is automatically computed
7332 by the build daemon by scanning all the files in the outputs.
7334 The @code{(guix derivations)} module provides a representation of
7335 derivations as Scheme objects, along with procedures to create and
7336 otherwise manipulate derivations. The lowest-level primitive to create
7337 a derivation is the @code{derivation} procedure:
7339 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
7340 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7341 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
7342 [#:system (%current-system)] [#:references-graphs #f] @
7343 [#:allowed-references #f] [#:disallowed-references #f] @
7344 [#:leaked-env-vars #f] [#:local-build? #f] @
7345 [#:substitutable? #t] [#:properties '()]
7346 Build a derivation with the given arguments, and return the resulting
7347 @code{<derivation>} object.
7349 When @var{hash} and @var{hash-algo} are given, a
7350 @dfn{fixed-output derivation} is created---i.e., one whose result is
7351 known in advance, such as a file download. If, in addition,
7352 @var{recursive?} is true, then that fixed output may be an executable
7353 file or a directory and @var{hash} must be the hash of an archive
7354 containing this output.
7356 When @var{references-graphs} is true, it must be a list of file
7357 name/store path pairs. In that case, the reference graph of each store
7358 path is exported in the build environment in the corresponding file, in
7359 a simple text format.
7361 When @var{allowed-references} is true, it must be a list of store items
7362 or outputs that the derivation's output may refer to. Likewise,
7363 @var{disallowed-references}, if true, must be a list of things the
7364 outputs may @emph{not} refer to.
7366 When @var{leaked-env-vars} is true, it must be a list of strings
7367 denoting environment variables that are allowed to ``leak'' from the
7368 daemon's environment to the build environment. This is only applicable
7369 to fixed-output derivations---i.e., when @var{hash} is true. The main
7370 use is to allow variables such as @code{http_proxy} to be passed to
7371 derivations that download files.
7373 When @var{local-build?} is true, declare that the derivation is not a
7374 good candidate for offloading and should rather be built locally
7375 (@pxref{Daemon Offload Setup}). This is the case for small derivations
7376 where the costs of data transfers would outweigh the benefits.
7378 When @var{substitutable?} is false, declare that substitutes of the
7379 derivation's output should not be used (@pxref{Substitutes}). This is
7380 useful, for instance, when building packages that capture details of the
7381 host CPU instruction set.
7383 @var{properties} must be an association list describing ``properties'' of the
7384 derivation. It is kept as-is, uninterpreted, in the derivation.
7388 Here's an example with a shell script as its builder, assuming
7389 @var{store} is an open connection to the daemon, and @var{bash} points
7390 to a Bash executable in the store:
7393 (use-modules (guix utils)
7397 (let ((builder ; add the Bash script to the store
7398 (add-text-to-store store "my-builder.sh"
7399 "echo hello world > $out\n" '())))
7400 (derivation store "foo"
7401 bash `("-e" ,builder)
7402 #:inputs `((,bash) (,builder))
7403 #:env-vars '(("HOME" . "/homeless"))))
7404 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
7407 As can be guessed, this primitive is cumbersome to use directly. A
7408 better approach is to write build scripts in Scheme, of course! The
7409 best course of action for that is to write the build code as a
7410 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
7411 information, @pxref{G-Expressions}.
7413 Once upon a time, @code{gexp->derivation} did not exist and constructing
7414 derivations with build code written in Scheme was achieved with
7415 @code{build-expression->derivation}, documented below. This procedure
7416 is now deprecated in favor of the much nicer @code{gexp->derivation}.
7418 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
7419 @var{name} @var{exp} @
7420 [#:system (%current-system)] [#:inputs '()] @
7421 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7422 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7423 [#:references-graphs #f] [#:allowed-references #f] @
7424 [#:disallowed-references #f] @
7425 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
7426 Return a derivation that executes Scheme expression @var{exp} as a
7427 builder for derivation @var{name}. @var{inputs} must be a list of
7428 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
7429 @code{"out"} is assumed. @var{modules} is a list of names of Guile
7430 modules from the current search path to be copied in the store,
7431 compiled, and made available in the load path during the execution of
7432 @var{exp}---e.g., @code{((guix build utils) (guix build
7433 gnu-build-system))}.
7435 @var{exp} is evaluated in an environment where @code{%outputs} is bound
7436 to a list of output/path pairs, and where @code{%build-inputs} is bound
7437 to a list of string/output-path pairs made from @var{inputs}.
7438 Optionally, @var{env-vars} is a list of string pairs specifying the name
7439 and value of environment variables visible to the builder. The builder
7440 terminates by passing the result of @var{exp} to @code{exit}; thus, when
7441 @var{exp} returns @code{#f}, the build is considered to have failed.
7443 @var{exp} is built using @var{guile-for-build} (a derivation). When
7444 @var{guile-for-build} is omitted or is @code{#f}, the value of the
7445 @code{%guile-for-build} fluid is used instead.
7447 See the @code{derivation} procedure for the meaning of
7448 @var{references-graphs}, @var{allowed-references},
7449 @var{disallowed-references}, @var{local-build?}, and
7450 @var{substitutable?}.
7454 Here's an example of a single-output derivation that creates a directory
7455 containing one file:
7458 (let ((builder '(let ((out (assoc-ref %outputs "out")))
7459 (mkdir out) ; create /gnu/store/@dots{}-goo
7460 (call-with-output-file (string-append out "/test")
7462 (display '(hello guix) p))))))
7463 (build-expression->derivation store "goo" builder))
7465 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
7469 @node The Store Monad
7470 @section The Store Monad
7474 The procedures that operate on the store described in the previous
7475 sections all take an open connection to the build daemon as their first
7476 argument. Although the underlying model is functional, they either have
7477 side effects or depend on the current state of the store.
7479 The former is inconvenient: the connection to the build daemon has to be
7480 carried around in all those functions, making it impossible to compose
7481 functions that do not take that parameter with functions that do. The
7482 latter can be problematic: since store operations have side effects
7483 and/or depend on external state, they have to be properly sequenced.
7485 @cindex monadic values
7486 @cindex monadic functions
7487 This is where the @code{(guix monads)} module comes in. This module
7488 provides a framework for working with @dfn{monads}, and a particularly
7489 useful monad for our uses, the @dfn{store monad}. Monads are a
7490 construct that allows two things: associating ``context'' with values
7491 (in our case, the context is the store), and building sequences of
7492 computations (here computations include accesses to the store). Values
7493 in a monad---values that carry this additional context---are called
7494 @dfn{monadic values}; procedures that return such values are called
7495 @dfn{monadic procedures}.
7497 Consider this ``normal'' procedure:
7500 (define (sh-symlink store)
7501 ;; Return a derivation that symlinks the 'bash' executable.
7502 (let* ((drv (package-derivation store bash))
7503 (out (derivation->output-path drv))
7504 (sh (string-append out "/bin/bash")))
7505 (build-expression->derivation store "sh"
7506 `(symlink ,sh %output))))
7509 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
7510 as a monadic function:
7513 (define (sh-symlink)
7514 ;; Same, but return a monadic value.
7515 (mlet %store-monad ((drv (package->derivation bash)))
7516 (gexp->derivation "sh"
7517 #~(symlink (string-append #$drv "/bin/bash")
7521 There are several things to note in the second version: the @code{store}
7522 parameter is now implicit and is ``threaded'' in the calls to the
7523 @code{package->derivation} and @code{gexp->derivation} monadic
7524 procedures, and the monadic value returned by @code{package->derivation}
7525 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
7527 As it turns out, the call to @code{package->derivation} can even be
7528 omitted since it will take place implicitly, as we will see later
7529 (@pxref{G-Expressions}):
7532 (define (sh-symlink)
7533 (gexp->derivation "sh"
7534 #~(symlink (string-append #$bash "/bin/bash")
7539 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
7540 @c for the funny quote.
7541 Calling the monadic @code{sh-symlink} has no effect. As someone once
7542 said, ``you exit a monad like you exit a building on fire: by running''.
7543 So, to exit the monad and get the desired effect, one must use
7544 @code{run-with-store}:
7547 (run-with-store (open-connection) (sh-symlink))
7548 @result{} /gnu/store/...-sh-symlink
7551 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
7552 new ``meta-commands'' to make it easier to deal with monadic procedures:
7553 @code{run-in-store}, and @code{enter-store-monad}. The former is used
7554 to ``run'' a single monadic value through the store:
7557 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
7558 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7561 The latter enters a recursive REPL, where all the return values are
7562 automatically run through the store:
7565 scheme@@(guile-user)> ,enter-store-monad
7566 store-monad@@(guile-user) [1]> (package->derivation hello)
7567 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7568 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
7569 $3 = "/gnu/store/@dots{}-foo"
7570 store-monad@@(guile-user) [1]> ,q
7571 scheme@@(guile-user)>
7575 Note that non-monadic values cannot be returned in the
7576 @code{store-monad} REPL.
7578 The main syntactic forms to deal with monads in general are provided by
7579 the @code{(guix monads)} module and are described below.
7581 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
7582 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
7586 @deffn {Scheme Syntax} return @var{val}
7587 Return a monadic value that encapsulates @var{val}.
7590 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
7591 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
7592 procedures @var{mproc}@dots{}@footnote{This operation is commonly
7593 referred to as ``bind'', but that name denotes an unrelated procedure in
7594 Guile. Thus we use this somewhat cryptic symbol inherited from the
7595 Haskell language.}. There can be one @var{mproc} or several of them, as
7600 (with-monad %state-monad
7602 (lambda (x) (return (+ 1 x)))
7603 (lambda (x) (return (* 2 x)))))
7607 @result{} some-state
7611 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
7613 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
7615 Bind the variables @var{var} to the monadic values @var{mval} in
7616 @var{body}, which is a sequence of expressions. As with the bind
7617 operator, this can be thought of as ``unpacking'' the raw, non-monadic
7618 value ``contained'' in @var{mval} and making @var{var} refer to that
7619 raw, non-monadic value within the scope of the @var{body}. The form
7620 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
7621 @var{val}, as per @code{let}. The binding operations occur in sequence
7622 from left to right. The last expression of @var{body} must be a monadic
7623 expression, and its result will become the result of the @code{mlet} or
7624 @code{mlet*} when run in the @var{monad}.
7626 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
7627 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
7630 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
7631 Bind @var{mexp} and the following monadic expressions in sequence,
7632 returning the result of the last expression. Every expression in the
7633 sequence must be a monadic expression.
7635 This is akin to @code{mlet}, except that the return values of the
7636 monadic expressions are ignored. In that sense, it is analogous to
7637 @code{begin}, but applied to monadic expressions.
7640 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
7641 When @var{condition} is true, evaluate the sequence of monadic
7642 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7643 @var{condition} is false, return @code{*unspecified*} in the current
7644 monad. Every expression in the sequence must be a monadic expression.
7647 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
7648 When @var{condition} is false, evaluate the sequence of monadic
7649 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7650 @var{condition} is true, return @code{*unspecified*} in the current
7651 monad. Every expression in the sequence must be a monadic expression.
7655 The @code{(guix monads)} module provides the @dfn{state monad}, which
7656 allows an additional value---the state---to be @emph{threaded} through
7657 monadic procedure calls.
7659 @defvr {Scheme Variable} %state-monad
7660 The state monad. Procedures in the state monad can access and change
7661 the state that is threaded.
7663 Consider the example below. The @code{square} procedure returns a value
7664 in the state monad. It returns the square of its argument, but also
7665 increments the current state value:
7669 (mlet %state-monad ((count (current-state)))
7670 (mbegin %state-monad
7671 (set-current-state (+ 1 count))
7674 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
7679 When ``run'' through @code{%state-monad}, we obtain that additional state
7680 value, which is the number of @code{square} calls.
7683 @deffn {Monadic Procedure} current-state
7684 Return the current state as a monadic value.
7687 @deffn {Monadic Procedure} set-current-state @var{value}
7688 Set the current state to @var{value} and return the previous state as a
7692 @deffn {Monadic Procedure} state-push @var{value}
7693 Push @var{value} to the current state, which is assumed to be a list,
7694 and return the previous state as a monadic value.
7697 @deffn {Monadic Procedure} state-pop
7698 Pop a value from the current state and return it as a monadic value.
7699 The state is assumed to be a list.
7702 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
7703 Run monadic value @var{mval} starting with @var{state} as the initial
7704 state. Return two values: the resulting value, and the resulting state.
7707 The main interface to the store monad, provided by the @code{(guix
7708 store)} module, is as follows.
7710 @defvr {Scheme Variable} %store-monad
7711 The store monad---an alias for @code{%state-monad}.
7713 Values in the store monad encapsulate accesses to the store. When its
7714 effect is needed, a value of the store monad must be ``evaluated'' by
7715 passing it to the @code{run-with-store} procedure (see below).
7718 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
7719 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
7720 open store connection.
7723 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
7724 Return as a monadic value the absolute file name in the store of the file
7725 containing @var{text}, a string. @var{references} is a list of store items that the
7726 resulting text file refers to; it defaults to the empty list.
7729 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
7730 Return as a monadic value the absolute file name in the store of the file
7731 containing @var{data}, a bytevector. @var{references} is a list of store
7732 items that the resulting binary file refers to; it defaults to the empty list.
7735 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
7736 [#:recursive? #t] [#:select? (const #t)]
7737 Return the name of @var{file} once interned in the store. Use
7738 @var{name} as its store name, or the basename of @var{file} if
7739 @var{name} is omitted.
7741 When @var{recursive?} is true, the contents of @var{file} are added
7742 recursively; if @var{file} designates a flat file and @var{recursive?}
7743 is true, its contents are added, and its permission bits are kept.
7745 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7746 @var{stat})} for each directory entry, where @var{file} is the entry's
7747 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7748 entries for which @var{select?} does not return true.
7750 The example below adds a file to the store, under two different names:
7753 (run-with-store (open-connection)
7754 (mlet %store-monad ((a (interned-file "README"))
7755 (b (interned-file "README" "LEGU-MIN")))
7756 (return (list a b))))
7758 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
7763 The @code{(guix packages)} module exports the following package-related
7766 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
7767 [#:system (%current-system)] [#:target #f] @
7770 value in the absolute file name of @var{file} within the @var{output}
7771 directory of @var{package}. When @var{file} is omitted, return the name
7772 of the @var{output} directory of @var{package}. When @var{target} is
7773 true, use it as a cross-compilation target triplet.
7775 Note that this procedure does @emph{not} build @var{package}. Thus, the
7776 result might or might not designate an existing file. We recommend not
7777 using this procedure unless you know what you are doing.
7780 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
7781 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7782 @var{target} [@var{system}]
7783 Monadic version of @code{package-derivation} and
7784 @code{package-cross-derivation} (@pxref{Defining Packages}).
7789 @section G-Expressions
7791 @cindex G-expression
7792 @cindex build code quoting
7793 So we have ``derivations'', which represent a sequence of build actions
7794 to be performed to produce an item in the store (@pxref{Derivations}).
7795 These build actions are performed when asking the daemon to actually
7796 build the derivations; they are run by the daemon in a container
7797 (@pxref{Invoking guix-daemon}).
7799 @cindex strata of code
7800 It should come as no surprise that we like to write these build actions
7801 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7802 code@footnote{The term @dfn{stratum} in this context was coined by
7803 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7804 Kiselyov, who has written insightful
7805 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7806 on this topic}, refers to this kind of code generation as
7807 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7808 to the daemon, etc.---and the ``build code''---code that actually
7809 performs build actions, such as making directories, invoking
7810 @command{make}, etc.
7812 To describe a derivation and its build actions, one typically needs to
7813 embed build code inside host code. It boils down to manipulating build
7814 code as data, and the homoiconicity of Scheme---code has a direct
7815 representation as data---comes in handy for that. But we need more than
7816 the normal @code{quasiquote} mechanism in Scheme to construct build
7819 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7820 S-expressions adapted to build expressions. G-expressions, or
7821 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7822 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7823 @code{#$}, and @code{#$@@}), which are comparable to
7824 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7825 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7826 GNU Guile Reference Manual}). However, there are major differences:
7830 Gexps are meant to be written to a file and run or manipulated by other
7834 When a high-level object such as a package or derivation is unquoted
7835 inside a gexp, the result is as if its output file name had been
7839 Gexps carry information about the packages or derivations they refer to,
7840 and these dependencies are automatically added as inputs to the build
7841 processes that use them.
7844 @cindex lowering, of high-level objects in gexps
7845 This mechanism is not limited to package and derivation
7846 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7847 derivations or files in the store can be defined,
7848 such that these objects can also be inserted
7849 into gexps. For example, a useful type of high-level objects that can be
7850 inserted in a gexp is ``file-like objects'', which make it easy to
7851 add files to the store and to refer to them in
7852 derivations and such (see @code{local-file} and @code{plain-file}
7855 To illustrate the idea, here is an example of a gexp:
7862 (symlink (string-append #$coreutils "/bin/ls")
7866 This gexp can be passed to @code{gexp->derivation}; we obtain a
7867 derivation that builds a directory containing exactly one symlink to
7868 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7871 (gexp->derivation "the-thing" build-exp)
7874 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7875 substituted to the reference to the @var{coreutils} package in the
7876 actual build code, and @var{coreutils} is automatically made an input to
7877 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7878 output)}) is replaced by a string containing the directory name of the
7879 output of the derivation.
7881 @cindex cross compilation
7882 In a cross-compilation context, it is useful to distinguish between
7883 references to the @emph{native} build of a package---that can run on the
7884 host---versus references to cross builds of a package. To that end, the
7885 @code{#+} plays the same role as @code{#$}, but is a reference to a
7886 native package build:
7889 (gexp->derivation "vi"
7892 (mkdir (string-append #$output "/bin"))
7893 (system* (string-append #+coreutils "/bin/ln")
7895 (string-append #$emacs "/bin/emacs")
7896 (string-append #$output "/bin/vi")))
7897 #:target "aarch64-linux-gnu")
7901 In the example above, the native build of @var{coreutils} is used, so
7902 that @command{ln} can actually run on the host; but then the
7903 cross-compiled build of @var{emacs} is referenced.
7905 @cindex imported modules, for gexps
7906 @findex with-imported-modules
7907 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7908 able to use certain Guile modules from the ``host environment'' in the
7909 gexp, so those modules should be imported in the ``build environment''.
7910 The @code{with-imported-modules} form allows you to express that:
7913 (let ((build (with-imported-modules '((guix build utils))
7915 (use-modules (guix build utils))
7916 (mkdir-p (string-append #$output "/bin"))))))
7917 (gexp->derivation "empty-dir"
7920 (display "success!\n")
7925 In this example, the @code{(guix build utils)} module is automatically
7926 pulled into the isolated build environment of our gexp, such that
7927 @code{(use-modules (guix build utils))} works as expected.
7929 @cindex module closure
7930 @findex source-module-closure
7931 Usually you want the @emph{closure} of the module to be imported---i.e.,
7932 the module itself and all the modules it depends on---rather than just
7933 the module; failing to do that, attempts to use the module will fail
7934 because of missing dependent modules. The @code{source-module-closure}
7935 procedure computes the closure of a module by looking at its source file
7936 headers, which comes in handy in this case:
7939 (use-modules (guix modules)) ;for 'source-module-closure'
7941 (with-imported-modules (source-module-closure
7942 '((guix build utils)
7944 (gexp->derivation "something-with-vms"
7946 (use-modules (guix build utils)
7951 @cindex extensions, for gexps
7952 @findex with-extensions
7953 In the same vein, sometimes you want to import not just pure-Scheme
7954 modules, but also ``extensions'' such as Guile bindings to C libraries
7955 or other ``full-blown'' packages. Say you need the @code{guile-json}
7956 package available on the build side, here's how you would do it:
7959 (use-modules (gnu packages guile)) ;for 'guile-json'
7961 (with-extensions (list guile-json)
7962 (gexp->derivation "something-with-json"
7964 (use-modules (json))
7968 The syntactic form to construct gexps is summarized below.
7970 @deffn {Scheme Syntax} #~@var{exp}
7971 @deffnx {Scheme Syntax} (gexp @var{exp})
7972 Return a G-expression containing @var{exp}. @var{exp} may contain one
7973 or more of the following forms:
7977 @itemx (ungexp @var{obj})
7978 Introduce a reference to @var{obj}. @var{obj} may have one of the
7979 supported types, for example a package or a
7980 derivation, in which case the @code{ungexp} form is replaced by its
7981 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7983 If @var{obj} is a list, it is traversed and references to supported
7984 objects are substituted similarly.
7986 If @var{obj} is another gexp, its contents are inserted and its
7987 dependencies are added to those of the containing gexp.
7989 If @var{obj} is another kind of object, it is inserted as is.
7991 @item #$@var{obj}:@var{output}
7992 @itemx (ungexp @var{obj} @var{output})
7993 This is like the form above, but referring explicitly to the
7994 @var{output} of @var{obj}---this is useful when @var{obj} produces
7995 multiple outputs (@pxref{Packages with Multiple Outputs}).
7998 @itemx #+@var{obj}:output
7999 @itemx (ungexp-native @var{obj})
8000 @itemx (ungexp-native @var{obj} @var{output})
8001 Same as @code{ungexp}, but produces a reference to the @emph{native}
8002 build of @var{obj} when used in a cross compilation context.
8004 @item #$output[:@var{output}]
8005 @itemx (ungexp output [@var{output}])
8006 Insert a reference to derivation output @var{output}, or to the main
8007 output when @var{output} is omitted.
8009 This only makes sense for gexps passed to @code{gexp->derivation}.
8012 @itemx (ungexp-splicing @var{lst})
8013 Like the above, but splices the contents of @var{lst} inside the
8017 @itemx (ungexp-native-splicing @var{lst})
8018 Like the above, but refers to native builds of the objects listed in
8023 G-expressions created by @code{gexp} or @code{#~} are run-time objects
8024 of the @code{gexp?} type (see below).
8027 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
8028 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
8029 in their execution environment.
8031 Each item in @var{modules} can be the name of a module, such as
8032 @code{(guix build utils)}, or it can be a module name, followed by an
8033 arrow, followed by a file-like object:
8036 `((guix build utils)
8038 ((guix config) => ,(scheme-file "config.scm"
8039 #~(define-module @dots{}))))
8043 In the example above, the first two modules are taken from the search
8044 path, and the last one is created from the given file-like object.
8046 This form has @emph{lexical} scope: it has an effect on the gexps
8047 directly defined in @var{body}@dots{}, but not on those defined, say, in
8048 procedures called from @var{body}@dots{}.
8051 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
8052 Mark the gexps defined in @var{body}@dots{} as requiring
8053 @var{extensions} in their build and execution environment.
8054 @var{extensions} is typically a list of package objects such as those
8055 defined in the @code{(gnu packages guile)} module.
8057 Concretely, the packages listed in @var{extensions} are added to the
8058 load path while compiling imported modules in @var{body}@dots{}; they
8059 are also added to the load path of the gexp returned by
8063 @deffn {Scheme Procedure} gexp? @var{obj}
8064 Return @code{#t} if @var{obj} is a G-expression.
8067 G-expressions are meant to be written to disk, either as code building
8068 some derivation, or as plain files in the store. The monadic procedures
8069 below allow you to do that (@pxref{The Store Monad}, for more
8070 information about monads).
8072 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
8073 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
8074 [#:hash #f] [#:hash-algo #f] @
8075 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
8076 [#:module-path @code{%load-path}] @
8077 [#:effective-version "2.2"] @
8078 [#:references-graphs #f] [#:allowed-references #f] @
8079 [#:disallowed-references #f] @
8080 [#:leaked-env-vars #f] @
8081 [#:script-name (string-append @var{name} "-builder")] @
8082 [#:deprecation-warnings #f] @
8083 [#:local-build? #f] [#:substitutable? #t] @
8084 [#:properties '()] [#:guile-for-build #f]
8085 Return a derivation @var{name} that runs @var{exp} (a gexp) with
8086 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
8087 stored in a file called @var{script-name}. When @var{target} is true,
8088 it is used as the cross-compilation target triplet for packages referred
8091 @var{modules} is deprecated in favor of @code{with-imported-modules}.
8093 make @var{modules} available in the evaluation context of @var{exp};
8094 @var{modules} is a list of names of Guile modules searched in
8095 @var{module-path} to be copied in the store, compiled, and made available in
8096 the load path during the execution of @var{exp}---e.g., @code{((guix
8097 build utils) (guix build gnu-build-system))}.
8099 @var{effective-version} determines the string to use when adding extensions of
8100 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
8102 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
8105 When @var{references-graphs} is true, it must be a list of tuples of one of the
8109 (@var{file-name} @var{package})
8110 (@var{file-name} @var{package} @var{output})
8111 (@var{file-name} @var{derivation})
8112 (@var{file-name} @var{derivation} @var{output})
8113 (@var{file-name} @var{store-item})
8116 The right-hand-side of each element of @var{references-graphs} is automatically made
8117 an input of the build process of @var{exp}. In the build environment, each
8118 @var{file-name} contains the reference graph of the corresponding item, in a simple
8121 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
8122 In the latter case, the list denotes store items that the result is allowed to
8123 refer to. Any reference to another store item will lead to a build error.
8124 Similarly for @var{disallowed-references}, which can list items that must not be
8125 referenced by the outputs.
8127 @var{deprecation-warnings} determines whether to show deprecation warnings while
8128 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
8130 The other arguments are as for @code{derivation} (@pxref{Derivations}).
8133 @cindex file-like objects
8134 The @code{local-file}, @code{plain-file}, @code{computed-file},
8135 @code{program-file}, and @code{scheme-file} procedures below return
8136 @dfn{file-like objects}. That is, when unquoted in a G-expression,
8137 these objects lead to a file in the store. Consider this G-expression:
8140 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
8141 #$(local-file "/tmp/my-nscd.conf"))
8144 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
8145 to the store. Once expanded, for instance @i{via}
8146 @code{gexp->derivation}, the G-expression refers to that copy under
8147 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
8148 does not have any effect on what the G-expression does.
8149 @code{plain-file} can be used similarly; it differs in that the file
8150 content is directly passed as a string.
8152 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
8153 [#:recursive? #f] [#:select? (const #t)]
8154 Return an object representing local file @var{file} to add to the store;
8155 this object can be used in a gexp. If @var{file} is a literal string
8156 denoting a relative file name, it is looked up relative to the source
8157 file where it appears; if @var{file} is not a literal string, it is
8158 looked up relative to the current working directory at run time.
8159 @var{file} will be added to the store under @var{name}--by default the
8160 base name of @var{file}.
8162 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
8163 designates a flat file and @var{recursive?} is true, its contents are added, and its
8164 permission bits are kept.
8166 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
8167 @var{stat})} for each directory entry, where @var{file} is the entry's
8168 absolute file name and @var{stat} is the result of @code{lstat}; exclude
8169 entries for which @var{select?} does not return true.
8171 This is the declarative counterpart of the @code{interned-file} monadic
8172 procedure (@pxref{The Store Monad, @code{interned-file}}).
8175 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
8176 Return an object representing a text file called @var{name} with the given
8177 @var{content} (a string or a bytevector) to be added to the store.
8179 This is the declarative counterpart of @code{text-file}.
8182 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
8183 [#:options '(#:local-build? #t)]
8184 Return an object representing the store item @var{name}, a file or
8185 directory computed by @var{gexp}. @var{options}
8186 is a list of additional arguments to pass to @code{gexp->derivation}.
8188 This is the declarative counterpart of @code{gexp->derivation}.
8191 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
8192 [#:guile (default-guile)] [#:module-path %load-path] @
8193 [#:system (%current-system)] [#:target #f]
8194 Return an executable script @var{name} that runs @var{exp} using
8195 @var{guile}, with @var{exp}'s imported modules in its search path.
8196 Look up @var{exp}'s modules in @var{module-path}.
8198 The example below builds a script that simply invokes the @command{ls}
8202 (use-modules (guix gexp) (gnu packages base))
8204 (gexp->script "list-files"
8205 #~(execl #$(file-append coreutils "/bin/ls")
8209 When ``running'' it through the store (@pxref{The Store Monad,
8210 @code{run-with-store}}), we obtain a derivation that produces an
8211 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
8214 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
8216 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
8220 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
8221 [#:guile #f] [#:module-path %load-path]
8222 Return an object representing the executable store item @var{name} that
8223 runs @var{gexp}. @var{guile} is the Guile package used to execute that
8224 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
8226 This is the declarative counterpart of @code{gexp->script}.
8229 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
8230 [#:set-load-path? #t] [#:module-path %load-path] @
8232 [#:guile (default-guile)]
8233 Return a derivation that builds a file @var{name} containing @var{exp}.
8234 When @var{splice?} is true, @var{exp} is considered to be a list of
8235 expressions that will be spliced in the resulting file.
8237 When @var{set-load-path?} is true, emit code in the resulting file to
8238 set @code{%load-path} and @code{%load-compiled-path} to honor
8239 @var{exp}'s imported modules. Look up @var{exp}'s modules in
8242 The resulting file holds references to all the dependencies of @var{exp}
8243 or a subset thereof.
8246 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
8247 [#:splice? #f] [#:set-load-path? #t]
8248 Return an object representing the Scheme file @var{name} that contains
8251 This is the declarative counterpart of @code{gexp->file}.
8254 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
8255 Return as a monadic value a derivation that builds a text file
8256 containing all of @var{text}. @var{text} may list, in addition to
8257 strings, objects of any type that can be used in a gexp: packages,
8258 derivations, local file objects, etc. The resulting store file holds
8259 references to all these.
8261 This variant should be preferred over @code{text-file} anytime the file
8262 to create will reference items from the store. This is typically the
8263 case when building a configuration file that embeds store file names,
8267 (define (profile.sh)
8268 ;; Return the name of a shell script in the store that
8269 ;; initializes the 'PATH' environment variable.
8270 (text-file* "profile.sh"
8271 "export PATH=" coreutils "/bin:"
8272 grep "/bin:" sed "/bin\n"))
8275 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
8276 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
8277 preventing them from being garbage-collected during its lifetime.
8280 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
8281 Return an object representing store file @var{name} containing
8282 @var{text}. @var{text} is a sequence of strings and file-like objects,
8286 (mixed-text-file "profile"
8287 "export PATH=" coreutils "/bin:" grep "/bin")
8290 This is the declarative counterpart of @code{text-file*}.
8293 @deffn {Scheme Procedure} file-union @var{name} @var{files}
8294 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
8295 Each item in @var{files} must be a two-element list where the first element is the
8296 file name to use in the new directory, and the second element is a gexp
8297 denoting the target file. Here's an example:
8301 `(("hosts" ,(plain-file "hosts"
8302 "127.0.0.1 localhost"))
8303 ("bashrc" ,(plain-file "bashrc"
8304 "alias ls='ls --color=auto'"))))
8307 This yields an @code{etc} directory containing these two files.
8310 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
8311 Return a directory that is the union of @var{things}, where @var{things} is a list of
8312 file-like objects denoting directories. For example:
8315 (directory-union "guile+emacs" (list guile emacs))
8318 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
8321 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
8322 Return a file-like object that expands to the concatenation of @var{obj}
8323 and @var{suffix}, where @var{obj} is a lowerable object and each
8324 @var{suffix} is a string.
8326 As an example, consider this gexp:
8329 (gexp->script "run-uname"
8330 #~(system* #$(file-append coreutils
8334 The same effect could be achieved with:
8337 (gexp->script "run-uname"
8338 #~(system* (string-append #$coreutils
8342 There is one difference though: in the @code{file-append} case, the
8343 resulting script contains the absolute file name as a string, whereas in
8344 the second case, the resulting script contains a @code{(string-append
8345 @dots{})} expression to construct the file name @emph{at run time}.
8348 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
8349 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
8350 Bind @var{system} to the currently targeted system---e.g.,
8351 @code{"x86_64-linux"}---within @var{body}.
8353 In the second case, additionally bind @var{target} to the current
8354 cross-compilation target---a GNU triplet such as
8355 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
8358 @code{let-system} is useful in the occasional case where the object
8359 spliced into the gexp depends on the target system, as in this example:
8363 #+(let-system system
8364 (cond ((string-prefix? "armhf-" system)
8365 (file-append qemu "/bin/qemu-system-arm"))
8366 ((string-prefix? "x86_64-" system)
8367 (file-append qemu "/bin/qemu-system-x86_64"))
8370 "-net" "user" #$image)
8374 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
8375 This macro is similar to the @code{parameterize} form for
8376 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
8377 Guile Reference Manual}). The key difference is that it takes effect
8378 when the file-like object returned by @var{exp} is lowered to a
8379 derivation or store item.
8381 A typical use of @code{with-parameters} is to force the system in effect
8385 (with-parameters ((%current-system "i686-linux"))
8389 The example above returns an object that corresponds to the i686 build
8390 of Coreutils, regardless of the current value of @code{%current-system}.
8394 Of course, in addition to gexps embedded in ``host'' code, there are
8395 also modules containing build tools. To make it clear that they are
8396 meant to be used in the build stratum, these modules are kept in the
8397 @code{(guix build @dots{})} name space.
8399 @cindex lowering, of high-level objects in gexps
8400 Internally, high-level objects are @dfn{lowered}, using their compiler,
8401 to either derivations or store items. For instance, lowering a package
8402 yields a derivation, and lowering a @code{plain-file} yields a store
8403 item. This is achieved using the @code{lower-object} monadic procedure.
8405 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
8407 Return as a value in @code{%store-monad} the derivation or store item
8408 corresponding to @var{obj} for @var{system}, cross-compiling for
8409 @var{target} if @var{target} is true. @var{obj} must be an object that
8410 has an associated gexp compiler, such as a @code{<package>}.
8413 @node Invoking guix repl
8414 @section Invoking @command{guix repl}
8416 @cindex REPL, read-eval-print loop, script
8417 The @command{guix repl} command makes it easier to program Guix in Guile
8418 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
8419 programming (@pxref{Using Guile Interactively,,, guile,
8420 GNU Guile Reference Manual}), or by running Guile scripts
8421 (@pxref{Running Guile Scripts,,, guile,
8422 GNU Guile Reference Manual}).
8423 Compared to just launching the @command{guile}
8424 command, @command{guix repl} guarantees that all the Guix modules and all its
8425 dependencies are available in the search path.
8427 The general syntax is:
8430 guix repl @var{options} [@var{file} @var{args}]
8433 When a @var{file} argument is provided, @var{file} is
8434 executed as a Guile scripts:
8437 guix repl my-script.scm
8440 To pass arguments to the script, use @code{--} to prevent them from
8441 being interpreted as arguments to @command{guix repl} itself:
8444 guix repl -- my-script.scm --input=foo.txt
8447 To make a script executable directly from the shell, using the guix
8448 executable that is on the user's search path, add the following two
8449 lines at the top of the script:
8452 @code{#!/usr/bin/env -S guix repl --}
8456 Without a file name argument, a Guile REPL is started:
8460 scheme@@(guile-user)> ,use (gnu packages base)
8461 scheme@@(guile-user)> coreutils
8462 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
8466 In addition, @command{guix repl} implements a simple machine-readable REPL
8467 protocol for use by @code{(guix inferior)}, a facility to interact with
8468 @dfn{inferiors}, separate processes running a potentially different revision
8471 The available options are as follows:
8474 @item --type=@var{type}
8475 @itemx -t @var{type}
8476 Start a REPL of the given @var{TYPE}, which can be one of the following:
8480 This is default, and it spawns a standard full-featured Guile REPL.
8482 Spawn a REPL that uses the machine-readable protocol. This is the protocol
8483 that the @code{(guix inferior)} module speaks.
8486 @item --listen=@var{endpoint}
8487 By default, @command{guix repl} reads from standard input and writes to
8488 standard output. When this option is passed, it will instead listen for
8489 connections on @var{endpoint}. Here are examples of valid options:
8492 @item --listen=tcp:37146
8493 Accept connections on localhost on port 37146.
8495 @item --listen=unix:/tmp/socket
8496 Accept connections on the Unix-domain socket @file{/tmp/socket}.
8499 @item --load-path=@var{directory}
8500 @itemx -L @var{directory}
8501 Add @var{directory} to the front of the package module search path
8502 (@pxref{Package Modules}).
8504 This allows users to define their own packages and make them visible to
8508 Inhibit loading of the @file{~/.guile} file. By default, that
8509 configuration file is loaded when spawning a @code{guile} REPL.
8512 @c *********************************************************************
8516 This section describes Guix command-line utilities. Some of them are
8517 primarily targeted at developers and users who write new package
8518 definitions, while others are more generally useful. They complement
8519 the Scheme programming interface of Guix in a convenient way.
8522 * Invoking guix build:: Building packages from the command line.
8523 * Invoking guix edit:: Editing package definitions.
8524 * Invoking guix download:: Downloading a file and printing its hash.
8525 * Invoking guix hash:: Computing the cryptographic hash of a file.
8526 * Invoking guix import:: Importing package definitions.
8527 * Invoking guix refresh:: Updating package definitions.
8528 * Invoking guix lint:: Finding errors in package definitions.
8529 * Invoking guix size:: Profiling disk usage.
8530 * Invoking guix graph:: Visualizing the graph of packages.
8531 * Invoking guix publish:: Sharing substitutes.
8532 * Invoking guix challenge:: Challenging substitute servers.
8533 * Invoking guix copy:: Copying to and from a remote store.
8534 * Invoking guix container:: Process isolation.
8535 * Invoking guix weather:: Assessing substitute availability.
8536 * Invoking guix processes:: Listing client processes.
8539 @node Invoking guix build
8540 @section Invoking @command{guix build}
8542 @cindex package building
8543 @cindex @command{guix build}
8544 The @command{guix build} command builds packages or derivations and
8545 their dependencies, and prints the resulting store paths. Note that it
8546 does not modify the user's profile---this is the job of the
8547 @command{guix package} command (@pxref{Invoking guix package}). Thus,
8548 it is mainly useful for distribution developers.
8550 The general syntax is:
8553 guix build @var{options} @var{package-or-derivation}@dots{}
8556 As an example, the following command builds the latest versions of Emacs
8557 and of Guile, displays their build logs, and finally displays the
8558 resulting directories:
8561 guix build emacs guile
8564 Similarly, the following command builds all the available packages:
8567 guix build --quiet --keep-going \
8568 `guix package -A | cut -f1,2 --output-delimiter=@@`
8571 @var{package-or-derivation} may be either the name of a package found in
8572 the software distribution such as @code{coreutils} or
8573 @code{coreutils@@8.20}, or a derivation such as
8574 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
8575 package with the corresponding name (and optionally version) is searched
8576 for among the GNU distribution modules (@pxref{Package Modules}).
8578 Alternatively, the @option{--expression} option may be used to specify a
8579 Scheme expression that evaluates to a package; this is useful when
8580 disambiguating among several same-named packages or package variants is
8583 There may be zero or more @var{options}. The available options are
8584 described in the subsections below.
8587 * Common Build Options:: Build options for most commands.
8588 * Package Transformation Options:: Creating variants of packages.
8589 * Additional Build Options:: Options specific to 'guix build'.
8590 * Debugging Build Failures:: Real life packaging experience.
8593 @node Common Build Options
8594 @subsection Common Build Options
8596 A number of options that control the build process are common to
8597 @command{guix build} and other commands that can spawn builds, such as
8598 @command{guix package} or @command{guix archive}. These are the
8603 @item --load-path=@var{directory}
8604 @itemx -L @var{directory}
8605 Add @var{directory} to the front of the package module search path
8606 (@pxref{Package Modules}).
8608 This allows users to define their own packages and make them visible to
8609 the command-line tools.
8613 Keep the build tree of failed builds. Thus, if a build fails, its build
8614 tree is kept under @file{/tmp}, in a directory whose name is shown at
8615 the end of the build log. This is useful when debugging build issues.
8616 @xref{Debugging Build Failures}, for tips and tricks on how to debug
8619 This option implies @option{--no-offload}, and it has no effect when
8620 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
8621 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
8625 Keep going when some of the derivations fail to build; return only once
8626 all the builds have either completed or failed.
8628 The default behavior is to stop as soon as one of the specified
8629 derivations has failed.
8633 Do not build the derivations.
8635 @anchor{fallback-option}
8637 When substituting a pre-built binary fails, fall back to building
8638 packages locally (@pxref{Substitution Failure}).
8640 @item --substitute-urls=@var{urls}
8641 @anchor{client-substitute-urls}
8642 Consider @var{urls} the whitespace-separated list of substitute source
8643 URLs, overriding the default list of URLs of @command{guix-daemon}
8644 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
8646 This means that substitutes may be downloaded from @var{urls}, provided
8647 they are signed by a key authorized by the system administrator
8648 (@pxref{Substitutes}).
8650 When @var{urls} is the empty string, substitutes are effectively
8653 @item --no-substitutes
8654 Do not use substitutes for build products. That is, always build things
8655 locally instead of allowing downloads of pre-built binaries
8656 (@pxref{Substitutes}).
8659 Do not ``graft'' packages. In practice, this means that package updates
8660 available as grafts are not applied. @xref{Security Updates}, for more
8661 information on grafts.
8663 @item --rounds=@var{n}
8664 Build each derivation @var{n} times in a row, and raise an error if
8665 consecutive build results are not bit-for-bit identical.
8667 This is a useful way to detect non-deterministic builds processes.
8668 Non-deterministic build processes are a problem because they make it
8669 practically impossible for users to @emph{verify} whether third-party
8670 binaries are genuine. @xref{Invoking guix challenge}, for more.
8672 Note that, currently, the differing build results are not kept around,
8673 so you will have to manually investigate in case of an error---e.g., by
8674 stashing one of the build results with @code{guix archive --export}
8675 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
8679 Do not use offload builds to other machines (@pxref{Daemon Offload
8680 Setup}). That is, always build things locally instead of offloading
8681 builds to remote machines.
8683 @item --max-silent-time=@var{seconds}
8684 When the build or substitution process remains silent for more than
8685 @var{seconds}, terminate it and report a build failure.
8687 By default, the daemon's setting is honored (@pxref{Invoking
8688 guix-daemon, @option{--max-silent-time}}).
8690 @item --timeout=@var{seconds}
8691 Likewise, when the build or substitution process lasts for more than
8692 @var{seconds}, terminate it and report a build failure.
8694 By default, the daemon's setting is honored (@pxref{Invoking
8695 guix-daemon, @option{--timeout}}).
8697 @c Note: This option is actually not part of %standard-build-options but
8698 @c most programs honor it.
8699 @cindex verbosity, of the command-line tools
8700 @cindex build logs, verbosity
8701 @item -v @var{level}
8702 @itemx --verbosity=@var{level}
8703 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
8704 output is produced, 1 is for quiet output, and 2 shows all the build log
8705 output on standard error.
8707 @item --cores=@var{n}
8709 Allow the use of up to @var{n} CPU cores for the build. The special
8710 value @code{0} means to use as many CPU cores as available.
8712 @item --max-jobs=@var{n}
8714 Allow at most @var{n} build jobs in parallel. @xref{Invoking
8715 guix-daemon, @option{--max-jobs}}, for details about this option and the
8716 equivalent @command{guix-daemon} option.
8718 @item --debug=@var{level}
8719 Produce debugging output coming from the build daemon. @var{level} must be an
8720 integer between 0 and 5; higher means more verbose output. Setting a level of
8721 4 or more may be helpful when debugging setup issues with the build daemon.
8725 Behind the scenes, @command{guix build} is essentially an interface to
8726 the @code{package-derivation} procedure of the @code{(guix packages)}
8727 module, and to the @code{build-derivations} procedure of the @code{(guix
8728 derivations)} module.
8730 In addition to options explicitly passed on the command line,
8731 @command{guix build} and other @command{guix} commands that support
8732 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
8734 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
8735 Users can define this variable to a list of command line options that
8736 will automatically be used by @command{guix build} and other
8737 @command{guix} commands that can perform builds, as in the example
8741 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
8744 These options are parsed independently, and the result is appended to
8745 the parsed command-line options.
8749 @node Package Transformation Options
8750 @subsection Package Transformation Options
8752 @cindex package variants
8753 Another set of command-line options supported by @command{guix build}
8754 and also @command{guix package} are @dfn{package transformation
8755 options}. These are options that make it possible to define @dfn{package
8756 variants}---for instance, packages built from different source code.
8757 This is a convenient way to create customized packages on the fly
8758 without having to type in the definitions of package variants
8759 (@pxref{Defining Packages}).
8763 @item --with-source=@var{source}
8764 @itemx --with-source=@var{package}=@var{source}
8765 @itemx --with-source=@var{package}@@@var{version}=@var{source}
8766 Use @var{source} as the source of @var{package}, and @var{version} as
8768 @var{source} must be a file name or a URL, as for @command{guix
8769 download} (@pxref{Invoking guix download}).
8771 When @var{package} is omitted,
8772 it is taken to be the package name specified on the
8773 command line that matches the base of @var{source}---e.g.,
8774 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
8775 package is @code{guile}.
8777 Likewise, when @var{version} is omitted, the version string is inferred from
8778 @var{source}; in the previous example, it is @code{2.0.10}.
8780 This option allows users to try out versions of packages other than the
8781 one provided by the distribution. The example below downloads
8782 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
8783 the @code{ed} package:
8786 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
8789 As a developer, @option{--with-source} makes it easy to test release
8793 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
8796 @dots{} or to build from a checkout in a pristine environment:
8799 $ git clone git://git.sv.gnu.org/guix.git
8800 $ guix build guix --with-source=guix@@1.0=./guix
8803 @item --with-input=@var{package}=@var{replacement}
8804 Replace dependency on @var{package} by a dependency on
8805 @var{replacement}. @var{package} must be a package name, and
8806 @var{replacement} must be a package specification such as @code{guile}
8807 or @code{guile@@1.8}.
8809 For instance, the following command builds Guix, but replaces its
8810 dependency on the current stable version of Guile with a dependency on
8811 the legacy version of Guile, @code{guile@@2.0}:
8814 guix build --with-input=guile=guile@@2.0 guix
8817 This is a recursive, deep replacement. So in this example, both
8818 @code{guix} and its dependency @code{guile-json} (which also depends on
8819 @code{guile}) get rebuilt against @code{guile@@2.0}.
8821 This is implemented using the @code{package-input-rewriting} Scheme
8822 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
8824 @item --with-graft=@var{package}=@var{replacement}
8825 This is similar to @option{--with-input} but with an important difference:
8826 instead of rebuilding the whole dependency chain, @var{replacement} is
8827 built and then @dfn{grafted} onto the binaries that were initially
8828 referring to @var{package}. @xref{Security Updates}, for more
8829 information on grafts.
8831 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
8832 and all its dependencies, replacing references to the version of GnuTLS
8833 they currently refer to:
8836 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
8839 This has the advantage of being much faster than rebuilding everything.
8840 But there is a caveat: it works if and only if @var{package} and
8841 @var{replacement} are strictly compatible---for example, if they provide
8842 a library, the application binary interface (ABI) of those libraries
8843 must be compatible. If @var{replacement} is somehow incompatible with
8844 @var{package}, then the resulting package may be unusable. Use with
8847 @item --with-git-url=@var{package}=@var{url}
8848 @cindex Git, using the latest commit
8849 @cindex latest commit, building
8850 Build @var{package} from the latest commit of the @code{master} branch of the
8851 Git repository at @var{url}. Git sub-modules of the repository are fetched,
8854 For example, the following command builds the NumPy Python library against the
8855 latest commit of the master branch of Python itself:
8858 guix build python-numpy \
8859 --with-git-url=python=https://github.com/python/cpython
8862 This option can also be combined with @option{--with-branch} or
8863 @option{--with-commit} (see below).
8865 @cindex continuous integration
8866 Obviously, since it uses the latest commit of the given branch, the result of
8867 such a command varies over time. Nevertheless it is a convenient way to
8868 rebuild entire software stacks against the latest commit of one or more
8869 packages. This is particularly useful in the context of continuous
8872 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
8873 consecutive accesses to the same repository. You may want to clean it up once
8874 in a while to save disk space.
8876 @item --with-branch=@var{package}=@var{branch}
8877 Build @var{package} from the latest commit of @var{branch}. If the
8878 @code{source} field of @var{package} is an origin with the @code{git-fetch}
8879 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
8880 repository URL is taken from that @code{source}. Otherwise you have to use
8881 @option{--with-git-url} to specify the URL of the Git repository.
8883 For instance, the following command builds @code{guile-sqlite3} from the
8884 latest commit of its @code{master} branch, and then builds @code{guix} (which
8885 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8886 specific @code{guile-sqlite3} build:
8889 guix build --with-branch=guile-sqlite3=master cuirass
8892 @item --with-commit=@var{package}=@var{commit}
8893 This is similar to @option{--with-branch}, except that it builds from
8894 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8895 Git commit SHA1 identifier or a tag.
8898 @node Additional Build Options
8899 @subsection Additional Build Options
8901 The command-line options presented below are specific to @command{guix
8908 Build quietly, without displaying the build log; this is equivalent to
8909 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8910 (or similar) and can always be retrieved using the @option{--log-file} option.
8912 @item --file=@var{file}
8913 @itemx -f @var{file}
8914 Build the package, derivation, or other file-like object that the code within
8915 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8917 As an example, @var{file} might contain a package definition like this
8918 (@pxref{Defining Packages}):
8921 @include package-hello.scm
8924 The @var{file} may also contain a JSON representation of one or more
8925 package definitions. Running @code{guix build -f} on @file{hello.json}
8926 with the following contents would result in building the packages
8927 @code{myhello} and @code{greeter}:
8930 @verbatiminclude package-hello.json
8933 @item --manifest=@var{manifest}
8934 @itemx -m @var{manifest}
8935 Build all packages listed in the given @var{manifest}
8936 (@pxref{profile-manifest, @option{--manifest}}).
8938 @item --expression=@var{expr}
8939 @itemx -e @var{expr}
8940 Build the package or derivation @var{expr} evaluates to.
8942 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8943 guile-1.8)}, which unambiguously designates this specific variant of
8944 version 1.8 of Guile.
8946 Alternatively, @var{expr} may be a G-expression, in which case it is used
8947 as a build program passed to @code{gexp->derivation}
8948 (@pxref{G-Expressions}).
8950 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8951 (@pxref{The Store Monad}). The procedure must return a derivation as a
8952 monadic value, which is then passed through @code{run-with-store}.
8956 Build the source derivations of the packages, rather than the packages
8959 For instance, @code{guix build -S gcc} returns something like
8960 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8963 The returned source tarball is the result of applying any patches and
8964 code snippets specified in the package @code{origin} (@pxref{Defining
8967 Note that @command{guix build -S} compiles the sources only of the
8968 specified packages. They do not include the sources of statically
8969 linked dependencies and by themselves are insufficient for reproducing
8973 Fetch and return the source of @var{package-or-derivation} and all their
8974 dependencies, recursively. This is a handy way to obtain a local copy
8975 of all the source code needed to build @var{packages}, allowing you to
8976 eventually build them even without network access. It is an extension
8977 of the @option{--source} option and can accept one of the following
8978 optional argument values:
8982 This value causes the @option{--sources} option to behave in the same way
8983 as the @option{--source} option.
8986 Build the source derivations of all packages, including any source that
8987 might be listed as @code{inputs}. This is the default value.
8990 $ guix build --sources tzdata
8991 The following derivations will be built:
8992 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8993 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8997 Build the source derivations of all packages, as well of all transitive
8998 inputs to the packages. This can be used e.g.@: to
8999 prefetch package source for later offline building.
9002 $ guix build --sources=transitive tzdata
9003 The following derivations will be built:
9004 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
9005 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
9006 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
9007 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
9008 /gnu/store/@dots{}-make-4.1.tar.xz.drv
9009 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
9015 @item --system=@var{system}
9016 @itemx -s @var{system}
9017 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
9018 the system type of the build host. The @command{guix build} command allows
9019 you to repeat this option several times, in which case it builds for all the
9020 specified systems; other commands ignore extraneous @option{-s} options.
9023 The @option{--system} flag is for @emph{native} compilation and must not
9024 be confused with cross-compilation. See @option{--target} below for
9025 information on cross-compilation.
9028 An example use of this is on Linux-based systems, which can emulate
9029 different personalities. For instance, passing
9030 @option{--system=i686-linux} on an @code{x86_64-linux} system or
9031 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
9032 you to build packages in a complete 32-bit environment.
9035 Building for an @code{armhf-linux} system is unconditionally enabled on
9036 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
9037 allow for this functionality, notably the ThunderX.
9040 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
9041 is enabled (@pxref{Virtualization Services,
9042 @code{qemu-binfmt-service-type}}), you can build for any system for
9043 which a QEMU @code{binfmt_misc} handler is installed.
9045 Builds for a system other than that of the machine you are using can
9046 also be offloaded to a remote machine of the right architecture.
9047 @xref{Daemon Offload Setup}, for more information on offloading.
9049 @item --target=@var{triplet}
9050 @cindex cross-compilation
9051 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
9052 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
9053 configuration triplets,, autoconf, Autoconf}).
9055 @anchor{build-check}
9057 @cindex determinism, checking
9058 @cindex reproducibility, checking
9059 Rebuild @var{package-or-derivation}, which are already available in the
9060 store, and raise an error if the build results are not bit-for-bit
9063 This mechanism allows you to check whether previously installed
9064 substitutes are genuine (@pxref{Substitutes}), or whether the build result
9065 of a package is deterministic. @xref{Invoking guix challenge}, for more
9066 background information and tools.
9068 When used in conjunction with @option{--keep-failed}, the differing
9069 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
9070 This makes it easy to look for differences between the two results.
9073 @cindex repairing store items
9074 @cindex corruption, recovering from
9075 Attempt to repair the specified store items, if they are corrupt, by
9076 re-downloading or rebuilding them.
9078 This operation is not atomic and thus restricted to @code{root}.
9082 Return the derivation paths, not the output paths, of the given
9085 @item --root=@var{file}
9086 @itemx -r @var{file}
9087 @cindex GC roots, adding
9088 @cindex garbage collector roots, adding
9089 Make @var{file} a symlink to the result, and register it as a garbage
9092 Consequently, the results of this @command{guix build} invocation are
9093 protected from garbage collection until @var{file} is removed. When
9094 that option is omitted, build results are eligible for garbage
9095 collection as soon as the build completes. @xref{Invoking guix gc}, for
9099 @cindex build logs, access
9100 Return the build log file names or URLs for the given
9101 @var{package-or-derivation}, or raise an error if build logs are
9104 This works regardless of how packages or derivations are specified. For
9105 instance, the following invocations are equivalent:
9108 guix build --log-file `guix build -d guile`
9109 guix build --log-file `guix build guile`
9110 guix build --log-file guile
9111 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
9114 If a log is unavailable locally, and unless @option{--no-substitutes} is
9115 passed, the command looks for a corresponding log on one of the
9116 substitute servers (as specified with @option{--substitute-urls}).
9118 So for instance, imagine you want to see the build log of GDB on MIPS,
9119 but you are actually on an @code{x86_64} machine:
9122 $ guix build --log-file gdb -s aarch64-linux
9123 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
9126 You can freely access a huge library of build logs!
9129 @node Debugging Build Failures
9130 @subsection Debugging Build Failures
9132 @cindex build failures, debugging
9133 When defining a new package (@pxref{Defining Packages}), you will
9134 probably find yourself spending some time debugging and tweaking the
9135 build until it succeeds. To do that, you need to operate the build
9136 commands yourself in an environment as close as possible to the one the
9139 To that end, the first thing to do is to use the @option{--keep-failed}
9140 or @option{-K} option of @command{guix build}, which will keep the
9141 failed build tree in @file{/tmp} or whatever directory you specified as
9142 @env{TMPDIR} (@pxref{Invoking guix build, @option{--keep-failed}}).
9144 From there on, you can @command{cd} to the failed build tree and source
9145 the @file{environment-variables} file, which contains all the
9146 environment variable definitions that were in place when the build
9147 failed. So let's say you're debugging a build failure in package
9148 @code{foo}; a typical session would look like this:
9152 @dots{} @i{build fails}
9153 $ cd /tmp/guix-build-foo.drv-0
9154 $ source ./environment-variables
9158 Now, you can invoke commands as if you were the daemon (almost) and
9159 troubleshoot your build process.
9161 Sometimes it happens that, for example, a package's tests pass when you
9162 run them manually but they fail when the daemon runs them. This can
9163 happen because the daemon runs builds in containers where, unlike in our
9164 environment above, network access is missing, @file{/bin/sh} does not
9165 exist, etc. (@pxref{Build Environment Setup}).
9167 In such cases, you may need to run inspect the build process from within
9168 a container similar to the one the build daemon creates:
9173 $ cd /tmp/guix-build-foo.drv-0
9174 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
9175 [env]# source ./environment-variables
9179 Here, @command{guix environment -C} creates a container and spawns a new
9180 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
9181 strace gdb} part adds the @command{strace} and @command{gdb} commands to
9182 the container, which you may find handy while debugging. The
9183 @option{--no-grafts} option makes sure we get the exact same
9184 environment, with ungrafted packages (@pxref{Security Updates}, for more
9187 To get closer to a container like that used by the build daemon, we can
9188 remove @file{/bin/sh}:
9194 (Don't worry, this is harmless: this is all happening in the throw-away
9195 container created by @command{guix environment}.)
9197 The @command{strace} command is probably not in the search path, but we
9201 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
9204 In this way, not only you will have reproduced the environment variables
9205 the daemon uses, you will also be running the build process in a container
9206 similar to the one the daemon uses.
9209 @node Invoking guix edit
9210 @section Invoking @command{guix edit}
9212 @cindex @command{guix edit}
9213 @cindex package definition, editing
9214 So many packages, so many source files! The @command{guix edit} command
9215 facilitates the life of users and packagers by pointing their editor at
9216 the source file containing the definition of the specified packages.
9220 guix edit gcc@@4.9 vim
9224 launches the program specified in the @env{VISUAL} or in the
9225 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
9228 If you are using a Guix Git checkout (@pxref{Building from Git}), or
9229 have created your own packages on @env{GUIX_PACKAGE_PATH}
9230 (@pxref{Package Modules}), you will be able to edit the package
9231 recipes. In other cases, you will be able to examine the read-only recipes
9232 for packages currently in the store.
9234 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
9235 @option{--load-path=@var{directory}} (or in short @option{-L
9236 @var{directory}}) allows you to add @var{directory} to the front of the
9237 package module search path and so make your own packages visible.
9239 @node Invoking guix download
9240 @section Invoking @command{guix download}
9242 @cindex @command{guix download}
9243 @cindex downloading package sources
9244 When writing a package definition, developers typically need to download
9245 a source tarball, compute its SHA256 hash, and write that
9246 hash in the package definition (@pxref{Defining Packages}). The
9247 @command{guix download} tool helps with this task: it downloads a file
9248 from the given URI, adds it to the store, and prints both its file name
9249 in the store and its SHA256 hash.
9251 The fact that the downloaded file is added to the store saves bandwidth:
9252 when the developer eventually tries to build the newly defined package
9253 with @command{guix build}, the source tarball will not have to be
9254 downloaded again because it is already in the store. It is also a
9255 convenient way to temporarily stash files, which may be deleted
9256 eventually (@pxref{Invoking guix gc}).
9258 The @command{guix download} command supports the same URIs as used in
9259 package definitions. In particular, it supports @code{mirror://} URIs.
9260 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
9261 Guile bindings for GnuTLS are available in the user's environment; when
9262 they are not available, an error is raised. @xref{Guile Preparations,
9263 how to install the GnuTLS bindings for Guile,, gnutls-guile,
9264 GnuTLS-Guile}, for more information.
9266 @command{guix download} verifies HTTPS server certificates by loading
9267 the certificates of X.509 authorities from the directory pointed to by
9268 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
9269 Certificates}), unless @option{--no-check-certificate} is used.
9271 The following options are available:
9274 @item --hash=@var{algorithm}
9275 @itemx -H @var{algorithm}
9276 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
9277 hash}, for more information.
9279 @item --format=@var{fmt}
9281 Write the hash in the format specified by @var{fmt}. For more
9282 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
9284 @item --no-check-certificate
9285 Do not validate the X.509 certificates of HTTPS servers.
9287 When using this option, you have @emph{absolutely no guarantee} that you
9288 are communicating with the authentic server responsible for the given
9289 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
9291 @item --output=@var{file}
9292 @itemx -o @var{file}
9293 Save the downloaded file to @var{file} instead of adding it to the
9297 @node Invoking guix hash
9298 @section Invoking @command{guix hash}
9300 @cindex @command{guix hash}
9301 The @command{guix hash} command computes the hash of a file.
9302 It is primarily a convenience tool for anyone contributing to the
9303 distribution: it computes the cryptographic hash of a file, which can be
9304 used in the definition of a package (@pxref{Defining Packages}).
9306 The general syntax is:
9309 guix hash @var{option} @var{file}
9312 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
9313 hash of data read from standard input. @command{guix hash} has the
9318 @item --hash=@var{algorithm}
9319 @itemx -H @var{algorithm}
9320 Compute a hash using the specified @var{algorithm}, @code{sha256} by
9323 @var{algorithm} must the name of a cryptographic hash algorithm
9324 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
9325 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
9328 @item --format=@var{fmt}
9330 Write the hash in the format specified by @var{fmt}.
9332 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
9333 (@code{hex} and @code{hexadecimal} can be used as well).
9335 If the @option{--format} option is not specified, @command{guix hash}
9336 will output the hash in @code{nix-base32}. This representation is used
9337 in the definitions of packages.
9341 Compute the hash on @var{file} recursively.
9343 In this case, the hash is computed on an archive containing @var{file},
9344 including its children if it is a directory. Some of the metadata of
9345 @var{file} is part of the archive; for instance, when @var{file} is a
9346 regular file, the hash is different depending on whether @var{file} is
9347 executable or not. Metadata such as time stamps has no impact on the
9348 hash (@pxref{Invoking guix archive}).
9349 @c FIXME: Replace xref above with xref to an ``Archive'' section when
9354 When combined with @option{--recursive}, exclude version control system
9355 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
9358 As an example, here is how you would compute the hash of a Git checkout,
9359 which is useful when using the @code{git-fetch} method (@pxref{origin
9363 $ git clone http://example.org/foo.git
9369 @node Invoking guix import
9370 @section Invoking @command{guix import}
9372 @cindex importing packages
9373 @cindex package import
9374 @cindex package conversion
9375 @cindex Invoking @command{guix import}
9376 The @command{guix import} command is useful for people who would like to
9377 add a package to the distribution with as little work as
9378 possible---a legitimate demand. The command knows of a few
9379 repositories from which it can ``import'' package metadata. The result
9380 is a package definition, or a template thereof, in the format we know
9381 (@pxref{Defining Packages}).
9383 The general syntax is:
9386 guix import @var{importer} @var{options}@dots{}
9389 @var{importer} specifies the source from which to import package
9390 metadata, and @var{options} specifies a package identifier and other
9391 options specific to @var{importer}.
9393 Some of the importers rely on the ability to run the @command{gpgv} command.
9394 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
9397 Currently, the available ``importers'' are:
9401 Import metadata for the given GNU package. This provides a template
9402 for the latest version of that GNU package, including the hash of its
9403 source tarball, and its canonical synopsis and description.
9405 Additional information such as the package dependencies and its
9406 license needs to be figured out manually.
9408 For example, the following command returns a package definition for
9412 guix import gnu hello
9415 Specific command-line options are:
9418 @item --key-download=@var{policy}
9419 As for @command{guix refresh}, specify the policy to handle missing
9420 OpenPGP keys when verifying the package signature. @xref{Invoking guix
9421 refresh, @option{--key-download}}.
9426 Import metadata from the @uref{https://pypi.python.org/, Python Package
9427 Index}. Information is taken from the JSON-formatted description
9428 available at @code{pypi.python.org} and usually includes all the relevant
9429 information, including package dependencies. For maximum efficiency, it
9430 is recommended to install the @command{unzip} utility, so that the
9431 importer can unzip Python wheels and gather data from them.
9433 The command below imports metadata for the @code{itsdangerous} Python
9437 guix import pypi itsdangerous
9443 Traverse the dependency graph of the given upstream package recursively
9444 and generate package expressions for all those packages that are not yet
9450 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
9451 is taken from the JSON-formatted description available at
9452 @code{rubygems.org} and includes most relevant information, including
9453 runtime dependencies. There are some caveats, however. The metadata
9454 doesn't distinguish between synopses and descriptions, so the same string
9455 is used for both fields. Additionally, the details of non-Ruby
9456 dependencies required to build native extensions is unavailable and left
9457 as an exercise to the packager.
9459 The command below imports metadata for the @code{rails} Ruby package:
9462 guix import gem rails
9468 Traverse the dependency graph of the given upstream package recursively
9469 and generate package expressions for all those packages that are not yet
9475 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
9476 Information is taken from the JSON-formatted metadata provided through
9477 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
9478 relevant information, such as module dependencies. License information
9479 should be checked closely. If Perl is available in the store, then the
9480 @code{corelist} utility will be used to filter core modules out of the
9481 list of dependencies.
9483 The command command below imports metadata for the Acme::Boolean Perl
9487 guix import cpan Acme::Boolean
9492 @cindex Bioconductor
9493 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
9494 central repository for the @uref{https://r-project.org, GNU@tie{}R
9495 statistical and graphical environment}.
9497 Information is extracted from the @file{DESCRIPTION} file of the package.
9499 The command command below imports metadata for the Cairo R package:
9502 guix import cran Cairo
9505 When @option{--recursive} is added, the importer will traverse the
9506 dependency graph of the given upstream package recursively and generate
9507 package expressions for all those packages that are not yet in Guix.
9509 When @option{--archive=bioconductor} is added, metadata is imported from
9510 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
9511 packages for for the analysis and comprehension of high-throughput
9512 genomic data in bioinformatics.
9514 Information is extracted from the @file{DESCRIPTION} file contained in the
9517 The command below imports metadata for the GenomicRanges R package:
9520 guix import cran --archive=bioconductor GenomicRanges
9523 Finally, you can also import R packages that have not yet been published on
9524 CRAN or Bioconductor as long as they are in a git repository. Use
9525 @option{--archive=git} followed by the URL of the git repository:
9528 guix import cran --archive=git https://github.com/immunogenomics/harmony
9534 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
9535 comprehensive TeX archive network for TeX packages that are part of the
9536 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
9538 Information about the package is obtained through the XML API provided
9539 by CTAN, while the source code is downloaded from the SVN repository of
9540 the Tex Live project. This is done because the CTAN does not keep
9543 The command command below imports metadata for the @code{fontspec}
9547 guix import texlive fontspec
9550 When @option{--archive=@var{directory}} is added, the source code is
9551 downloaded not from the @file{latex} sub-directory of the
9552 @file{texmf-dist/source} tree in the TeX Live SVN repository, but from
9553 the specified sibling @var{directory} under the same root.
9555 The command below imports metadata for the @code{ifxetex} package from
9556 CTAN while fetching the sources from the directory
9557 @file{texmf/source/generic}:
9560 guix import texlive --archive=generic ifxetex
9564 @cindex JSON, import
9565 Import package metadata from a local JSON file. Consider the following
9566 example package definition in JSON format:
9572 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
9573 "build-system": "gnu",
9574 "home-page": "https://www.gnu.org/software/hello/",
9575 "synopsis": "Hello, GNU world: An example GNU package",
9576 "description": "GNU Hello prints a greeting.",
9577 "license": "GPL-3.0+",
9578 "native-inputs": ["gettext"]
9582 The field names are the same as for the @code{<package>} record
9583 (@xref{Defining Packages}). References to other packages are provided
9584 as JSON lists of quoted package specification strings such as
9585 @code{guile} or @code{guile@@2.0}.
9587 The importer also supports a more explicit source definition using the
9588 common fields for @code{<origin>} records:
9594 "method": "url-fetch",
9595 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
9597 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
9604 The command below reads metadata from the JSON file @code{hello.json}
9605 and outputs a package expression:
9608 guix import json hello.json
9612 Import metadata from a local copy of the source of the
9613 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
9614 relies on the @command{nix-instantiate} command of
9615 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
9616 typically written in a mixture of Nix-language and Bash code. This
9617 command only imports the high-level package structure that is written in
9618 the Nix language. It normally includes all the basic fields of a
9621 When importing a GNU package, the synopsis and descriptions are replaced
9622 by their canonical upstream variant.
9624 Usually, you will first need to do:
9627 export NIX_REMOTE=daemon
9631 so that @command{nix-instantiate} does not try to open the Nix database.
9633 As an example, the command below imports the package definition of
9634 LibreOffice (more precisely, it imports the definition of the package
9635 bound to the @code{libreoffice} top-level attribute):
9638 guix import nix ~/path/to/nixpkgs libreoffice
9643 Import metadata from the Haskell community's central package archive
9644 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
9645 Cabal files and includes all the relevant information, including package
9648 Specific command-line options are:
9653 Read a Cabal file from standard input.
9654 @item --no-test-dependencies
9656 Do not include dependencies required only by the test suites.
9657 @item --cabal-environment=@var{alist}
9658 @itemx -e @var{alist}
9659 @var{alist} is a Scheme alist defining the environment in which the
9660 Cabal conditionals are evaluated. The accepted keys are: @code{os},
9661 @code{arch}, @code{impl} and a string representing the name of a flag.
9662 The value associated with a flag has to be either the symbol
9663 @code{true} or @code{false}. The value associated with other keys
9664 has to conform to the Cabal file format definition. The default value
9665 associated with the keys @code{os}, @code{arch} and @code{impl} is
9666 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
9669 Traverse the dependency graph of the given upstream package recursively
9670 and generate package expressions for all those packages that are not yet
9674 The command below imports metadata for the latest version of the
9675 HTTP Haskell package without including test dependencies and
9676 specifying the value of the flag @samp{network-uri} as @code{false}:
9679 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
9682 A specific package version may optionally be specified by following the
9683 package name by an at-sign and a version number as in the following example:
9686 guix import hackage mtl@@2.1.3.1
9691 The @code{stackage} importer is a wrapper around the @code{hackage} one.
9692 It takes a package name, looks up the package version included in a
9693 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
9694 release and uses the @code{hackage} importer to retrieve its metadata.
9695 Note that it is up to you to select an LTS release compatible with the
9696 GHC compiler used by Guix.
9698 Specific command-line options are:
9701 @item --no-test-dependencies
9703 Do not include dependencies required only by the test suites.
9704 @item --lts-version=@var{version}
9705 @itemx -l @var{version}
9706 @var{version} is the desired LTS release version. If omitted the latest
9710 Traverse the dependency graph of the given upstream package recursively
9711 and generate package expressions for all those packages that are not yet
9715 The command below imports metadata for the HTTP Haskell package
9716 included in the LTS Stackage release version 7.18:
9719 guix import stackage --lts-version=7.18 HTTP
9724 Import metadata from an Emacs Lisp Package Archive (ELPA) package
9725 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9727 Specific command-line options are:
9730 @item --archive=@var{repo}
9731 @itemx -a @var{repo}
9732 @var{repo} identifies the archive repository from which to retrieve the
9733 information. Currently the supported repositories and their identifiers
9737 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
9738 identifier. This is the default.
9740 Packages from @code{elpa.gnu.org} are signed with one of the keys
9741 contained in the GnuPG keyring at
9742 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
9743 @code{emacs} package (@pxref{Package Installation, ELPA package
9744 signatures,, emacs, The GNU Emacs Manual}).
9747 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
9748 @code{melpa-stable} identifier.
9751 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
9757 Traverse the dependency graph of the given upstream package recursively
9758 and generate package expressions for all those packages that are not yet
9764 Import metadata from the crates.io Rust package repository
9765 @uref{https://crates.io, crates.io}, as in this example:
9768 guix import crate blake2-rfc
9771 The crate importer also allows you to specify a version string:
9774 guix import crate constant-time-eq@@0.1.0
9777 Additional options include:
9782 Traverse the dependency graph of the given upstream package recursively
9783 and generate package expressions for all those packages that are not yet
9790 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
9791 repository used by the OCaml community.
9794 The structure of the @command{guix import} code is modular. It would be
9795 useful to have more importers for other package formats, and your help
9796 is welcome here (@pxref{Contributing}).
9798 @node Invoking guix refresh
9799 @section Invoking @command{guix refresh}
9801 @cindex @command {guix refresh}
9802 The primary audience of the @command{guix refresh} command is developers
9803 of the GNU software distribution. By default, it reports any packages
9804 provided by the distribution that are outdated compared to the latest
9805 upstream version, like this:
9809 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
9810 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
9813 Alternatively, one can specify packages to consider, in which case a
9814 warning is emitted for packages that lack an updater:
9817 $ guix refresh coreutils guile guile-ssh
9818 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
9819 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
9822 @command{guix refresh} browses the upstream repository of each package and determines
9823 the highest version number of the releases therein. The command
9824 knows how to update specific types of packages: GNU packages, ELPA
9825 packages, etc.---see the documentation for @option{--type} below. There
9826 are many packages, though, for which it lacks a method to determine
9827 whether a new upstream release is available. However, the mechanism is
9828 extensible, so feel free to get in touch with us to add a new method!
9833 Consider the packages specified, and all the packages upon which they depend.
9836 $ guix refresh --recursive coreutils
9837 gnu/packages/acl.scm:35:2: warning: no updater for acl
9838 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
9839 gnu/packages/xml.scm:68:2: warning: no updater for expat
9840 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
9846 Sometimes the upstream name differs from the package name used in Guix,
9847 and @command{guix refresh} needs a little help. Most updaters honor the
9848 @code{upstream-name} property in package definitions, which can be used
9852 (define-public network-manager
9854 (name "network-manager")
9856 (properties '((upstream-name . "NetworkManager")))))
9859 When passed @option{--update}, it modifies distribution source files to
9860 update the version numbers and source tarball hashes of those package
9861 recipes (@pxref{Defining Packages}). This is achieved by downloading
9862 each package's latest source tarball and its associated OpenPGP
9863 signature, authenticating the downloaded tarball against its signature
9864 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
9865 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
9868 key used to sign the tarball is missing from the user's keyring, an
9869 attempt is made to automatically retrieve it from a public key server;
9870 when this is successful, the key is added to the user's keyring; otherwise,
9871 @command{guix refresh} reports an error.
9873 The following options are supported:
9877 @item --expression=@var{expr}
9878 @itemx -e @var{expr}
9879 Consider the package @var{expr} evaluates to.
9881 This is useful to precisely refer to a package, as in this example:
9884 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
9887 This command lists the dependents of the ``final'' libc (essentially all
9892 Update distribution source files (package recipes) in place. This is
9893 usually run from a checkout of the Guix source tree (@pxref{Running
9894 Guix Before It Is Installed}):
9897 $ ./pre-inst-env guix refresh -s non-core -u
9900 @xref{Defining Packages}, for more information on package definitions.
9902 @item --select=[@var{subset}]
9903 @itemx -s @var{subset}
9904 Select all the packages in @var{subset}, one of @code{core} or
9907 The @code{core} subset refers to all the packages at the core of the
9908 distribution---i.e., packages that are used to build ``everything
9909 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
9910 changing one of these packages in the distribution entails a rebuild of
9911 all the others. Thus, such updates are an inconvenience to users in
9912 terms of build time or bandwidth used to achieve the upgrade.
9914 The @code{non-core} subset refers to the remaining packages. It is
9915 typically useful in cases where an update of the core packages would be
9918 @item --manifest=@var{file}
9919 @itemx -m @var{file}
9920 Select all the packages from the manifest in @var{file}. This is useful to
9921 check if any packages of the user manifest can be updated.
9923 @item --type=@var{updater}
9924 @itemx -t @var{updater}
9925 Select only packages handled by @var{updater} (may be a comma-separated
9926 list of updaters). Currently, @var{updater} may be one of:
9930 the updater for GNU packages;
9932 the updater for GNOME packages;
9934 the updater for KDE packages;
9936 the updater for X.org packages;
9938 the updater for packages hosted on kernel.org;
9940 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
9942 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
9944 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
9946 the updater for @uref{https://www.cpan.org/, CPAN} packages;
9948 the updater for @uref{https://pypi.python.org, PyPI} packages.
9950 the updater for @uref{https://rubygems.org, RubyGems} packages.
9952 the updater for @uref{https://github.com, GitHub} packages.
9954 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9956 the updater for @uref{https://www.stackage.org, Stackage} packages.
9958 the updater for @uref{https://crates.io, Crates} packages.
9960 the updater for @uref{https://launchpad.net, Launchpad} packages.
9963 For instance, the following command only checks for updates of Emacs
9964 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9967 $ guix refresh --type=elpa,cran
9968 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9969 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9974 In addition, @command{guix refresh} can be passed one or more package
9975 names, as in this example:
9978 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9982 The command above specifically updates the @code{emacs} and
9983 @code{idutils} packages. The @option{--select} option would have no
9984 effect in this case.
9986 When considering whether to upgrade a package, it is sometimes
9987 convenient to know which packages would be affected by the upgrade and
9988 should be checked for compatibility. For this the following option may
9989 be used when passing @command{guix refresh} one or more package names:
9993 @item --list-updaters
9995 List available updaters and exit (see @option{--type} above).
9997 For each updater, display the fraction of packages it covers; at the
9998 end, display the fraction of packages covered by all these updaters.
10000 @item --list-dependent
10002 List top-level dependent packages that would need to be rebuilt as a
10003 result of upgrading one or more packages.
10005 @xref{Invoking guix graph, the @code{reverse-package} type of
10006 @command{guix graph}}, for information on how to visualize the list of
10007 dependents of a package.
10011 Be aware that the @option{--list-dependent} option only
10012 @emph{approximates} the rebuilds that would be required as a result of
10013 an upgrade. More rebuilds might be required under some circumstances.
10016 $ guix refresh --list-dependent flex
10017 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
10018 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
10021 The command above lists a set of packages that could be built to check
10022 for compatibility with an upgraded @code{flex} package.
10026 @item --list-transitive
10027 List all the packages which one or more packages depend upon.
10030 $ guix refresh --list-transitive flex
10031 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
10032 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{}
10037 The command above lists a set of packages which, when changed, would cause
10038 @code{flex} to be rebuilt.
10040 The following options can be used to customize GnuPG operation:
10044 @item --gpg=@var{command}
10045 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
10046 for in @code{$PATH}.
10048 @item --keyring=@var{file}
10049 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
10050 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
10051 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
10052 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
10053 information on a tool to manipulate keybox files).
10055 When this option is omitted, @command{guix refresh} uses
10056 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
10057 signing keys. OpenPGP signatures are checked against keys from this keyring;
10058 missing keys are downloaded to this keyring as well (see
10059 @option{--key-download} below).
10061 You can export keys from your default GPG keyring into a keybox file using
10062 commands like this one:
10065 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
10068 Likewise, you can fetch keys to a specific keybox file like this:
10071 gpg --no-default-keyring --keyring mykeyring.kbx \
10072 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
10075 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
10076 Privacy Guard}, for more information on GPG's @option{--keyring} option.
10078 @item --key-download=@var{policy}
10079 Handle missing OpenPGP keys according to @var{policy}, which may be one
10084 Always download missing OpenPGP keys from the key server, and add them
10085 to the user's GnuPG keyring.
10088 Never try to download missing OpenPGP keys. Instead just bail out.
10091 When a package signed with an unknown OpenPGP key is encountered, ask
10092 the user whether to download it or not. This is the default behavior.
10095 @item --key-server=@var{host}
10096 Use @var{host} as the OpenPGP key server when importing a public key.
10098 @item --load-path=@var{directory}
10099 Add @var{directory} to the front of the package module search path
10100 (@pxref{Package Modules}).
10102 This allows users to define their own packages and make them visible to
10103 the command-line tools.
10107 The @code{github} updater uses the
10108 @uref{https://developer.github.com/v3/, GitHub API} to query for new
10109 releases. When used repeatedly e.g.@: when refreshing all packages,
10110 GitHub will eventually refuse to answer any further API requests. By
10111 default 60 API requests per hour are allowed, and a full refresh on all
10112 GitHub packages in Guix requires more than this. Authentication with
10113 GitHub through the use of an API token alleviates these limits. To use
10114 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
10115 token procured from @uref{https://github.com/settings/tokens} or
10119 @node Invoking guix lint
10120 @section Invoking @command{guix lint}
10122 @cindex @command{guix lint}
10123 @cindex package, checking for errors
10124 The @command{guix lint} command is meant to help package developers avoid
10125 common errors and use a consistent style. It runs a number of checks on
10126 a given set of packages in order to find common mistakes in their
10127 definitions. Available @dfn{checkers} include (see
10128 @option{--list-checkers} for a complete list):
10133 Validate certain typographical and stylistic rules about package
10134 descriptions and synopses.
10136 @item inputs-should-be-native
10137 Identify inputs that should most likely be native inputs.
10143 @itemx source-file-name
10144 Probe @code{home-page} and @code{source} URLs and report those that are
10145 invalid. Suggest a @code{mirror://} URL when applicable. If the
10146 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
10147 URL. Check that the source file name is meaningful, e.g.@: is not just a
10148 version number or ``git-checkout'', without a declared @code{file-name}
10149 (@pxref{origin Reference}).
10151 @item source-unstable-tarball
10152 Parse the @code{source} URL to determine if a tarball from GitHub is
10153 autogenerated or if it is a release tarball. Unfortunately GitHub's
10154 autogenerated tarballs are sometimes regenerated.
10157 Check that the derivation of the given packages can be successfully
10158 computed for all the supported systems (@pxref{Derivations}).
10160 @item profile-collisions
10161 Check whether installing the given packages in a profile would lead to
10162 collisions. Collisions occur when several packages with the same name
10163 but a different version or a different store file name are propagated.
10164 @xref{package Reference, @code{propagated-inputs}}, for more information
10165 on propagated inputs.
10168 @cindex Software Heritage, source code archive
10169 @cindex archival of source code, Software Heritage
10170 Checks whether the package's source code is archived at
10171 @uref{https://www.softwareheritage.org, Software Heritage}.
10173 When the source code that is not archived comes from a version-control system
10174 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
10175 ``save'' request so that it eventually archives it. This ensures that the
10176 source will remain available in the long term, and that Guix can fall back to
10177 Software Heritage should the source code disappear from its original host.
10178 The status of recent ``save'' requests can be
10179 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
10181 When source code is a tarball obtained with @code{url-fetch}, simply print a
10182 message when it is not archived. As of this writing, Software Heritage does
10183 not allow requests to save arbitrary tarballs; we are working on ways to
10184 ensure that non-VCS source code is also archived.
10187 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
10188 request rate per IP address}. When the limit is reached, @command{guix lint}
10189 prints a message and the @code{archival} checker stops doing anything until
10190 that limit has been reset.
10193 @cindex security vulnerabilities
10194 @cindex CVE, Common Vulnerabilities and Exposures
10195 Report known vulnerabilities found in the Common Vulnerabilities and
10196 Exposures (CVE) databases of the current and past year
10197 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
10200 To view information about a particular vulnerability, visit pages such as:
10204 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
10206 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
10210 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
10211 @code{CVE-2015-7554}.
10213 Package developers can specify in package recipes the
10214 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
10215 name and version of the package when they differ from the name or version
10216 that Guix uses, as in this example:
10222 ;; CPE calls this package "grub2".
10223 (properties '((cpe-name . "grub2")
10224 (cpe-version . "2.3"))))
10227 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
10228 Some entries in the CVE database do not specify which version of a
10229 package they apply to, and would thus ``stick around'' forever. Package
10230 developers who found CVE alerts and verified they can be ignored can
10231 declare them as in this example:
10237 ;; These CVEs no longer apply and can be safely ignored.
10238 (properties `((lint-hidden-cve . ("CVE-2011-0433"
10241 "CVE-2011-5244")))))
10245 Warn about obvious source code formatting issues: trailing white space,
10246 use of tabulations, etc.
10249 The general syntax is:
10252 guix lint @var{options} @var{package}@dots{}
10255 If no package is given on the command line, then all packages are checked.
10256 The @var{options} may be zero or more of the following:
10259 @item --list-checkers
10261 List and describe all the available checkers that will be run on packages
10266 Only enable the checkers specified in a comma-separated list using the
10267 names returned by @option{--list-checkers}.
10269 @item --load-path=@var{directory}
10270 @itemx -L @var{directory}
10271 Add @var{directory} to the front of the package module search path
10272 (@pxref{Package Modules}).
10274 This allows users to define their own packages and make them visible to
10275 the command-line tools.
10279 @node Invoking guix size
10280 @section Invoking @command{guix size}
10283 @cindex package size
10285 @cindex @command{guix size}
10286 The @command{guix size} command helps package developers profile the
10287 disk usage of packages. It is easy to overlook the impact of an
10288 additional dependency added to a package, or the impact of using a
10289 single output for a package that could easily be split (@pxref{Packages
10290 with Multiple Outputs}). Such are the typical issues that
10291 @command{guix size} can highlight.
10293 The command can be passed one or more package specifications
10294 such as @code{gcc@@4.8}
10295 or @code{guile:debug}, or a file name in the store. Consider this
10299 $ guix size coreutils
10300 store item total self
10301 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
10302 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
10303 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
10304 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
10305 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
10306 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
10307 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
10308 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
10313 The store items listed here constitute the @dfn{transitive closure} of
10314 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
10315 would be returned by:
10318 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
10321 Here the output shows three columns next to store items. The first column,
10322 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
10323 the store item---that is, its own size plus the size of all its
10324 dependencies. The next column, labeled ``self'', shows the size of the
10325 item itself. The last column shows the ratio of the size of the item
10326 itself to the space occupied by all the items listed here.
10328 In this example, we see that the closure of Coreutils weighs in at
10329 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
10330 libraries. (That libc and GCC's libraries represent a large fraction of
10331 the closure is not a problem @i{per se} because they are always available
10332 on the system anyway.)
10334 Since the command also accepts store file names, assessing the size of
10335 a build result is straightforward:
10338 guix size $(guix system build config.scm)
10341 When the package(s) passed to @command{guix size} are available in the
10342 store@footnote{More precisely, @command{guix size} looks for the
10343 @emph{ungrafted} variant of the given package(s), as returned by
10344 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
10345 for information on grafts.}, @command{guix size} queries the daemon to determine its
10346 dependencies, and measures its size in the store, similar to @command{du
10347 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
10350 When the given packages are @emph{not} in the store, @command{guix size}
10351 reports information based on the available substitutes
10352 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
10353 store items that are not even on disk, only available remotely.
10355 You can also specify several package names:
10358 $ guix size coreutils grep sed bash
10359 store item total self
10360 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
10361 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
10362 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
10363 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
10369 In this example we see that the combination of the four packages takes
10370 102.3@tie{}MiB in total, which is much less than the sum of each closure
10371 since they have a lot of dependencies in common.
10373 When looking at the profile returned by @command{guix size}, you may
10374 find yourself wondering why a given package shows up in the profile at
10375 all. To understand it, you can use @command{guix graph --path -t
10376 references} to display the shortest path between the two packages
10377 (@pxref{Invoking guix graph}).
10379 The available options are:
10383 @item --substitute-urls=@var{urls}
10384 Use substitute information from @var{urls}.
10385 @xref{client-substitute-urls, the same option for @code{guix build}}.
10387 @item --sort=@var{key}
10388 Sort lines according to @var{key}, one of the following options:
10392 the size of each item (the default);
10394 the total size of the item's closure.
10397 @item --map-file=@var{file}
10398 Write a graphical map of disk usage in PNG format to @var{file}.
10400 For the example above, the map looks like this:
10402 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
10403 produced by @command{guix size}}
10405 This option requires that
10406 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
10407 installed and visible in Guile's module search path. When that is not
10408 the case, @command{guix size} fails as it tries to load it.
10410 @item --system=@var{system}
10411 @itemx -s @var{system}
10412 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
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.
10423 @node Invoking guix graph
10424 @section Invoking @command{guix graph}
10427 @cindex @command{guix graph}
10428 @cindex package dependencies
10429 Packages and their dependencies form a @dfn{graph}, specifically a
10430 directed acyclic graph (DAG). It can quickly become difficult to have a
10431 mental model of the package DAG, so the @command{guix graph} command
10432 provides a visual representation of the DAG. By default,
10433 @command{guix graph} emits a DAG representation in the input format of
10434 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
10435 directly to the @command{dot} command of Graphviz. It can also emit an
10436 HTML page with embedded JavaScript code to display a ``chord diagram''
10437 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
10438 emit Cypher queries to construct a graph in a graph database supporting
10439 the @uref{https://www.opencypher.org/, openCypher} query language. With
10440 @option{--path}, it simply displays the shortest path between two
10441 packages. The general syntax is:
10444 guix graph @var{options} @var{package}@dots{}
10447 For example, the following command generates a PDF file representing the
10448 package DAG for the GNU@tie{}Core Utilities, showing its build-time
10452 guix graph coreutils | dot -Tpdf > dag.pdf
10455 The output looks like this:
10457 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
10459 Nice little graph, no?
10461 You may find it more pleasant to navigate the graph interactively with
10462 @command{xdot} (from the @code{xdot} package):
10465 guix graph coreutils | xdot -
10468 But there is more than one graph! The one above is concise: it is the
10469 graph of package objects, omitting implicit inputs such as GCC, libc,
10470 grep, etc. It is often useful to have such a concise graph, but
10471 sometimes one may want to see more details. @command{guix graph} supports
10472 several types of graphs, allowing you to choose the level of detail:
10476 This is the default type used in the example above. It shows the DAG of
10477 package objects, excluding implicit dependencies. It is concise, but
10478 filters out many details.
10480 @item reverse-package
10481 This shows the @emph{reverse} DAG of packages. For example:
10484 guix graph --type=reverse-package ocaml
10487 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
10488 you are also interested in cases where OCaml is an implicit dependency, see
10489 @code{reverse-bag} below).
10491 Note that for core packages this can yield huge graphs. If all you want
10492 is to know the number of packages that depend on a given package, use
10493 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
10494 @option{--list-dependent}}).
10497 This is the package DAG, @emph{including} implicit inputs.
10499 For instance, the following command:
10502 guix graph --type=bag-emerged coreutils
10505 ...@: yields this bigger graph:
10507 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
10509 At the bottom of the graph, we see all the implicit inputs of
10510 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
10512 Now, note that the dependencies of these implicit inputs---that is, the
10513 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
10514 here, for conciseness.
10517 Similar to @code{bag-emerged}, but this time including all the bootstrap
10520 @item bag-with-origins
10521 Similar to @code{bag}, but also showing origins and their dependencies.
10524 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
10525 it also takes implicit dependencies into account. For example:
10528 guix graph -t reverse-bag dune
10532 ...@: yields the graph of all packages that depend on Dune, directly or
10533 indirectly. Since Dune is an @emph{implicit} dependency of many packages
10534 @i{via} @code{dune-build-system}, this shows a large number of packages,
10535 whereas @code{reverse-package} would show very few if any.
10538 This is the most detailed representation: It shows the DAG of
10539 derivations (@pxref{Derivations}) and plain store items. Compared to
10540 the above representation, many additional nodes are visible, including
10541 build scripts, patches, Guile modules, etc.
10543 For this type of graph, it is also possible to pass a @file{.drv} file
10544 name instead of a package name, as in:
10547 guix graph -t derivation `guix system build -d my-config.scm`
10551 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
10552 For example, the following command shows the graph for the package
10553 module that defines the @code{guile} package:
10556 guix graph -t module guile | xdot -
10560 All the types above correspond to @emph{build-time dependencies}. The
10561 following graph type represents the @emph{run-time dependencies}:
10565 This is the graph of @dfn{references} of a package output, as returned
10566 by @command{guix gc --references} (@pxref{Invoking guix gc}).
10568 If the given package output is not available in the store, @command{guix
10569 graph} attempts to obtain dependency information from substitutes.
10571 Here you can also pass a store file name instead of a package name. For
10572 example, the command below produces the reference graph of your profile
10573 (which can be big!):
10576 guix graph -t references `readlink -f ~/.guix-profile`
10580 This is the graph of the @dfn{referrers} of a store item, as returned by
10581 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
10583 This relies exclusively on local information from your store. For
10584 instance, let us suppose that the current Inkscape is available in 10
10585 profiles on your machine; @command{guix graph -t referrers inkscape}
10586 will show a graph rooted at Inkscape and with those 10 profiles linked
10589 It can help determine what is preventing a store item from being garbage
10594 @cindex shortest path, between packages
10595 Often, the graph of the package you are interested in does not fit on
10596 your screen, and anyway all you want to know is @emph{why} that package
10597 actually depends on some seemingly unrelated package. The
10598 @option{--path} option instructs @command{guix graph} to display the
10599 shortest path between two packages (or derivations, or store items,
10603 $ guix graph --path emacs libunistring
10606 libunistring@@0.9.10
10607 $ guix graph --path -t derivation emacs libunistring
10608 /gnu/store/@dots{}-emacs-26.3.drv
10609 /gnu/store/@dots{}-mailutils-3.9.drv
10610 /gnu/store/@dots{}-libunistring-0.9.10.drv
10611 $ guix graph --path -t references emacs libunistring
10612 /gnu/store/@dots{}-emacs-26.3
10613 /gnu/store/@dots{}-libidn2-2.2.0
10614 /gnu/store/@dots{}-libunistring-0.9.10
10617 The available options are the following:
10620 @item --type=@var{type}
10621 @itemx -t @var{type}
10622 Produce a graph output of @var{type}, where @var{type} must be one of
10623 the values listed above.
10626 List the supported graph types.
10628 @item --backend=@var{backend}
10629 @itemx -b @var{backend}
10630 Produce a graph using the selected @var{backend}.
10632 @item --list-backends
10633 List the supported graph backends.
10635 Currently, the available backends are Graphviz and d3.js.
10638 Display the shortest path between two nodes of the type specified by
10639 @option{--type}. The example below shows the shortest path between
10640 @code{libreoffice} and @code{llvm} according to the references of
10641 @code{libreoffice}:
10644 $ guix graph --path -t references libreoffice llvm
10645 /gnu/store/@dots{}-libreoffice-6.4.2.2
10646 /gnu/store/@dots{}-libepoxy-1.5.4
10647 /gnu/store/@dots{}-mesa-19.3.4
10648 /gnu/store/@dots{}-llvm-9.0.1
10651 @item --expression=@var{expr}
10652 @itemx -e @var{expr}
10653 Consider the package @var{expr} evaluates to.
10655 This is useful to precisely refer to a package, as in this example:
10658 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
10661 @item --system=@var{system}
10662 @itemx -s @var{system}
10663 Display the graph for @var{system}---e.g., @code{i686-linux}.
10665 The package dependency graph is largely architecture-independent, but there
10666 are some architecture-dependent bits that this option allows you to visualize.
10668 @item --load-path=@var{directory}
10669 @itemx -L @var{directory}
10670 Add @var{directory} to the front of the package module search path
10671 (@pxref{Package Modules}).
10673 This allows users to define their own packages and make them visible to
10674 the command-line tools.
10677 On top of that, @command{guix graph} supports all the usual package
10678 transformation options (@pxref{Package Transformation Options}). This
10679 makes it easy to view the effect of a graph-rewriting transformation
10680 such as @option{--with-input}. For example, the command below outputs
10681 the graph of @code{git} once @code{openssl} has been replaced by
10682 @code{libressl} everywhere in the graph:
10685 guix graph git --with-input=openssl=libressl
10688 So many possibilities, so much fun!
10690 @node Invoking guix publish
10691 @section Invoking @command{guix publish}
10693 @cindex @command{guix publish}
10694 The purpose of @command{guix publish} is to enable users to easily share
10695 their store with others, who can then use it as a substitute server
10696 (@pxref{Substitutes}).
10698 When @command{guix publish} runs, it spawns an HTTP server which allows
10699 anyone with network access to obtain substitutes from it. This means
10700 that any machine running Guix can also act as if it were a build farm,
10701 since the HTTP interface is compatible with Cuirass, the software behind
10702 the @code{@value{SUBSTITUTE-SERVER}} build farm.
10704 For security, each substitute is signed, allowing recipients to check
10705 their authenticity and integrity (@pxref{Substitutes}). Because
10706 @command{guix publish} uses the signing key of the system, which is only
10707 readable by the system administrator, it must be started as root; the
10708 @option{--user} option makes it drop root privileges early on.
10710 The signing key pair must be generated before @command{guix publish} is
10711 launched, using @command{guix archive --generate-key} (@pxref{Invoking
10714 The general syntax is:
10717 guix publish @var{options}@dots{}
10720 Running @command{guix publish} without any additional arguments will
10721 spawn an HTTP server on port 8080:
10727 Once a publishing server has been authorized (@pxref{Invoking guix
10728 archive}), the daemon may download substitutes from it:
10731 guix-daemon --substitute-urls=http://example.org:8080
10734 By default, @command{guix publish} compresses archives on the fly as it
10735 serves them. This ``on-the-fly'' mode is convenient in that it requires
10736 no setup and is immediately available. However, when serving lots of
10737 clients, we recommend using the @option{--cache} option, which enables
10738 caching of the archives before they are sent to clients---see below for
10739 details. The @command{guix weather} command provides a handy way to
10740 check what a server provides (@pxref{Invoking guix weather}).
10742 As a bonus, @command{guix publish} also serves as a content-addressed
10743 mirror for source files referenced in @code{origin} records
10744 (@pxref{origin Reference}). For instance, assuming @command{guix
10745 publish} is running on @code{example.org}, the following URL returns the
10746 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
10747 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
10750 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
10753 Obviously, these URLs only work for files that are in the store; in
10754 other cases, they return 404 (``Not Found'').
10756 @cindex build logs, publication
10757 Build logs are available from @code{/log} URLs like:
10760 http://example.org/log/gwspk@dots{}-guile-2.2.3
10764 When @command{guix-daemon} is configured to save compressed build logs,
10765 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
10766 URLs return the compressed log as-is, with an appropriate
10767 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
10768 running @command{guix-daemon} with @option{--log-compression=gzip} since
10769 Web browsers can automatically decompress it, which is not the case with
10772 The following options are available:
10775 @item --port=@var{port}
10776 @itemx -p @var{port}
10777 Listen for HTTP requests on @var{port}.
10779 @item --listen=@var{host}
10780 Listen on the network interface for @var{host}. The default is to
10781 accept connections from any interface.
10783 @item --user=@var{user}
10784 @itemx -u @var{user}
10785 Change privileges to @var{user} as soon as possible---i.e., once the
10786 server socket is open and the signing key has been read.
10788 @item --compression[=@var{method}[:@var{level}]]
10789 @itemx -C [@var{method}[:@var{level}]]
10790 Compress data using the given @var{method} and @var{level}. @var{method} is
10791 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
10794 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
10795 to different compression levels: 1 is the fastest, and 9 is the best
10796 (CPU-intensive). The default is 3.
10798 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
10799 increase in CPU usage; see
10800 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
10803 Unless @option{--cache} is used, compression occurs on the fly and
10804 the compressed streams are not
10805 cached. Thus, to reduce load on the machine that runs @command{guix
10806 publish}, it may be a good idea to choose a low compression level, to
10807 run @command{guix publish} behind a caching proxy, or to use
10808 @option{--cache}. Using @option{--cache} has the advantage that it
10809 allows @command{guix publish} to add @code{Content-Length} HTTP header
10812 This option can be repeated, in which case every substitute gets compressed
10813 using all the selected methods, and all of them are advertised. This is
10814 useful when users may not support all the compression methods: they can select
10815 the one they support.
10817 @item --cache=@var{directory}
10818 @itemx -c @var{directory}
10819 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
10820 and only serve archives that are in cache.
10822 When this option is omitted, archives and meta-data are created
10823 on-the-fly. This can reduce the available bandwidth, especially when
10824 compression is enabled, since this may become CPU-bound. Another
10825 drawback of the default mode is that the length of archives is not known
10826 in advance, so @command{guix publish} does not add a
10827 @code{Content-Length} HTTP header to its responses, which in turn
10828 prevents clients from knowing the amount of data being downloaded.
10830 Conversely, when @option{--cache} is used, the first request for a store
10831 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
10832 background process to @dfn{bake} the archive---computing its
10833 @code{.narinfo} and compressing the archive, if needed. Once the
10834 archive is cached in @var{directory}, subsequent requests succeed and
10835 are served directly from the cache, which guarantees that clients get
10836 the best possible bandwidth.
10838 The ``baking'' process is performed by worker threads. By default, one
10839 thread per CPU core is created, but this can be customized. See
10840 @option{--workers} below.
10842 When @option{--ttl} is used, cached entries are automatically deleted
10843 when they have expired.
10845 @item --workers=@var{N}
10846 When @option{--cache} is used, request the allocation of @var{N} worker
10847 threads to ``bake'' archives.
10849 @item --ttl=@var{ttl}
10850 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
10851 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
10852 days, @code{1m} means 1 month, and so on.
10854 This allows the user's Guix to keep substitute information in cache for
10855 @var{ttl}. However, note that @code{guix publish} does not itself
10856 guarantee that the store items it provides will indeed remain available
10857 for as long as @var{ttl}.
10859 Additionally, when @option{--cache} is used, cached entries that have
10860 not been accessed for @var{ttl} and that no longer have a corresponding
10861 item in the store, may be deleted.
10863 @item --nar-path=@var{path}
10864 Use @var{path} as the prefix for the URLs of ``nar'' files
10865 (@pxref{Invoking guix archive, normalized archives}).
10867 By default, nars are served at a URL such as
10868 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
10869 change the @code{/nar} part to @var{path}.
10871 @item --public-key=@var{file}
10872 @itemx --private-key=@var{file}
10873 Use the specific @var{file}s as the public/private key pair used to sign
10874 the store items being published.
10876 The files must correspond to the same key pair (the private key is used
10877 for signing and the public key is merely advertised in the signature
10878 metadata). They must contain keys in the canonical s-expression format
10879 as produced by @command{guix archive --generate-key} (@pxref{Invoking
10880 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
10881 @file{/etc/guix/signing-key.sec} are used.
10883 @item --repl[=@var{port}]
10884 @itemx -r [@var{port}]
10885 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
10886 Reference Manual}) on @var{port} (37146 by default). This is used
10887 primarily for debugging a running @command{guix publish} server.
10890 Enabling @command{guix publish} on Guix System is a one-liner: just
10891 instantiate a @code{guix-publish-service-type} service in the @code{services} field
10892 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
10893 @code{guix-publish-service-type}}).
10895 If you are instead running Guix on a ``foreign distro'', follow these
10900 If your host distro uses the systemd init system:
10903 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
10904 /etc/systemd/system/
10905 # systemctl start guix-publish && systemctl enable guix-publish
10909 If your host distro uses the Upstart init system:
10912 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
10913 # start guix-publish
10917 Otherwise, proceed similarly with your distro's init system.
10920 @node Invoking guix challenge
10921 @section Invoking @command{guix challenge}
10923 @cindex reproducible builds
10924 @cindex verifiable builds
10925 @cindex @command{guix challenge}
10927 Do the binaries provided by this server really correspond to the source
10928 code it claims to build? Is a package build process deterministic?
10929 These are the questions the @command{guix challenge} command attempts to
10932 The former is obviously an important question: Before using a substitute
10933 server (@pxref{Substitutes}), one had better @emph{verify} that it
10934 provides the right binaries, and thus @emph{challenge} it. The latter
10935 is what enables the former: If package builds are deterministic, then
10936 independent builds of the package should yield the exact same result,
10937 bit for bit; if a server provides a binary different from the one
10938 obtained locally, it may be either corrupt or malicious.
10940 We know that the hash that shows up in @file{/gnu/store} file names is
10941 the hash of all the inputs of the process that built the file or
10942 directory---compilers, libraries, build scripts,
10943 etc. (@pxref{Introduction}). Assuming deterministic build processes,
10944 one store file name should map to exactly one build output.
10945 @command{guix challenge} checks whether there is, indeed, a single
10946 mapping by comparing the build outputs of several independent builds of
10947 any given store item.
10949 The command output looks like this:
10952 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10953 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
10954 updating list of substitutes from 'https://guix.example.org'... 100.0%
10955 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
10956 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10957 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10958 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
10960 /lib/libcrypto.so.1.1
10963 /gnu/store/@dots{}-git-2.5.0 contents differ:
10964 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
10965 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
10966 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
10968 /libexec/git-core/git-fsck
10970 /gnu/store/@dots{}-pius-2.1.1 contents differ:
10971 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10972 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10973 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
10975 /share/man/man1/pius.1.gz
10979 6,406 store items were analyzed:
10980 - 4,749 (74.1%) were identical
10981 - 525 (8.2%) differed
10982 - 1,132 (17.7%) were inconclusive
10986 In this example, @command{guix challenge} first scans the store to
10987 determine the set of locally-built derivations---as opposed to store
10988 items that were downloaded from a substitute server---and then queries
10989 all the substitute servers. It then reports those store items for which
10990 the servers obtained a result different from the local build.
10992 @cindex non-determinism, in package builds
10993 As an example, @code{guix.example.org} always gets a different answer.
10994 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
10995 case of Git. This might indicate that the build process of Git is
10996 non-deterministic, meaning that its output varies as a function of
10997 various things that Guix does not fully control, in spite of building
10998 packages in isolated environments (@pxref{Features}). Most common
10999 sources of non-determinism include the addition of timestamps in build
11000 results, the inclusion of random numbers, and directory listings sorted
11001 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
11004 To find out what is wrong with this Git binary, the easiest approach is
11008 guix challenge git \
11009 --diff=diffoscope \
11010 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
11013 This automatically invokes @command{diffoscope}, which displays detailed
11014 information about files that differ.
11016 Alternatively, we can do something along these lines (@pxref{Invoking guix
11020 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-git-2.5.0 \
11021 | lzip -d | guix archive -x /tmp/git
11022 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
11025 This command shows the difference between the files resulting from the
11026 local build, and the files resulting from the build on
11027 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
11028 diffutils, Comparing and Merging Files}). The @command{diff} command
11029 works great for text files. When binary files differ, a better option
11030 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
11031 visualize differences for all kinds of files.
11033 Once you have done that work, you can tell whether the differences are due
11034 to a non-deterministic build process or to a malicious server. We try
11035 hard to remove sources of non-determinism in packages to make it easier
11036 to verify substitutes, but of course, this is a process that
11037 involves not just Guix, but a large part of the free software community.
11038 In the meantime, @command{guix challenge} is one tool to help address
11041 If you are writing packages for Guix, you are encouraged to check
11042 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
11043 same build result as you did with:
11046 $ guix challenge @var{package}
11050 where @var{package} is a package specification such as
11051 @code{guile@@2.0} or @code{glibc:debug}.
11053 The general syntax is:
11056 guix challenge @var{options} [@var{packages}@dots{}]
11059 When a difference is found between the hash of a locally-built item and
11060 that of a server-provided substitute, or among substitutes provided by
11061 different servers, the command displays it as in the example above and
11062 its exit code is 2 (other non-zero exit codes denote other kinds of
11065 The one option that matters is:
11069 @item --substitute-urls=@var{urls}
11070 Consider @var{urls} the whitespace-separated list of substitute source
11071 URLs to compare to.
11073 @item --diff=@var{mode}
11074 Upon mismatches, show differences according to @var{mode}, one of:
11077 @item @code{simple} (the default)
11078 Show the list of files that differ.
11080 @item @code{diffoscope}
11081 @itemx @var{command}
11082 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
11083 two directories whose contents do not match.
11085 When @var{command} is an absolute file name, run @var{command} instead
11089 Do not show further details about the differences.
11092 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
11093 downloads the store items from the given substitute servers so that it
11098 Show details about matches (identical contents) in addition to
11099 information about mismatches.
11103 @node Invoking guix copy
11104 @section Invoking @command{guix copy}
11106 @cindex copy, of store items, over SSH
11107 @cindex SSH, copy of store items
11108 @cindex sharing store items across machines
11109 @cindex transferring store items across machines
11110 The @command{guix copy} command copies items from the store of one
11111 machine to that of another machine over a secure shell (SSH)
11112 connection@footnote{This command is available only when Guile-SSH was
11113 found. @xref{Requirements}, for details.}. For example, the following
11114 command copies the @code{coreutils} package, the user's profile, and all
11115 their dependencies over to @var{host}, logged in as @var{user}:
11118 guix copy --to=@var{user}@@@var{host} \
11119 coreutils `readlink -f ~/.guix-profile`
11122 If some of the items to be copied are already present on @var{host},
11123 they are not actually sent.
11125 The command below retrieves @code{libreoffice} and @code{gimp} from
11126 @var{host}, assuming they are available there:
11129 guix copy --from=@var{host} libreoffice gimp
11132 The SSH connection is established using the Guile-SSH client, which is
11133 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
11134 @file{~/.ssh/config}, and uses the SSH agent for authentication.
11136 The key used to sign items that are sent must be accepted by the remote
11137 machine. Likewise, the key used by the remote machine to sign items you
11138 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
11139 own daemon. @xref{Invoking guix archive}, for more information about
11140 store item authentication.
11142 The general syntax is:
11145 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
11148 You must always specify one of the following options:
11151 @item --to=@var{spec}
11152 @itemx --from=@var{spec}
11153 Specify the host to send to or receive from. @var{spec} must be an SSH
11154 spec such as @code{example.org}, @code{charlie@@example.org}, or
11155 @code{charlie@@example.org:2222}.
11158 The @var{items} can be either package names, such as @code{gimp}, or
11159 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
11161 When specifying the name of a package to send, it is first built if
11162 needed, unless @option{--dry-run} was specified. Common build options
11163 are supported (@pxref{Common Build Options}).
11166 @node Invoking guix container
11167 @section Invoking @command{guix container}
11169 @cindex @command{guix container}
11171 As of version @value{VERSION}, this tool is experimental. The interface
11172 is subject to radical change in the future.
11175 The purpose of @command{guix container} is to manipulate processes
11176 running within an isolated environment, commonly known as a
11177 ``container'', typically created by the @command{guix environment}
11178 (@pxref{Invoking guix environment}) and @command{guix system container}
11179 (@pxref{Invoking guix system}) commands.
11181 The general syntax is:
11184 guix container @var{action} @var{options}@dots{}
11187 @var{action} specifies the operation to perform with a container, and
11188 @var{options} specifies the context-specific arguments for the action.
11190 The following actions are available:
11194 Execute a command within the context of a running container.
11199 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
11202 @var{pid} specifies the process ID of the running container.
11203 @var{program} specifies an executable file name within the root file
11204 system of the container. @var{arguments} are the additional options that
11205 will be passed to @var{program}.
11207 The following command launches an interactive login shell inside a
11208 Guix system container, started by @command{guix system container}, and whose
11209 process ID is 9001:
11212 guix container exec 9001 /run/current-system/profile/bin/bash --login
11215 Note that the @var{pid} cannot be the parent process of a container. It
11216 must be PID 1 of the container or one of its child processes.
11220 @node Invoking guix weather
11221 @section Invoking @command{guix weather}
11223 Occasionally you're grumpy because substitutes are lacking and you end
11224 up building packages by yourself (@pxref{Substitutes}). The
11225 @command{guix weather} command reports on substitute availability on the
11226 specified servers so you can have an idea of whether you'll be grumpy
11227 today. It can sometimes be useful info as a user, but it is primarily
11228 useful to people running @command{guix publish} (@pxref{Invoking guix
11231 @cindex statistics, for substitutes
11232 @cindex availability of substitutes
11233 @cindex substitute availability
11234 @cindex weather, substitute availability
11235 Here's a sample run:
11238 $ guix weather --substitute-urls=https://guix.example.org
11239 computing 5,872 package derivations for x86_64-linux...
11240 looking for 6,128 store items on https://guix.example.org..
11241 updating list of substitutes from 'https://guix.example.org'... 100.0%
11242 https://guix.example.org
11243 43.4% substitutes available (2,658 out of 6,128)
11244 7,032.5 MiB of nars (compressed)
11245 19,824.2 MiB on disk (uncompressed)
11246 0.030 seconds per request (182.9 seconds in total)
11247 33.5 requests per second
11249 9.8% (342 out of 3,470) of the missing items are queued
11251 x86_64-linux: 518 (59.7%)
11252 i686-linux: 221 (25.5%)
11253 aarch64-linux: 128 (14.8%)
11254 build rate: 23.41 builds per hour
11255 x86_64-linux: 11.16 builds per hour
11256 i686-linux: 6.03 builds per hour
11257 aarch64-linux: 6.41 builds per hour
11260 @cindex continuous integration, statistics
11261 As you can see, it reports the fraction of all the packages for which
11262 substitutes are available on the server---regardless of whether
11263 substitutes are enabled, and regardless of whether this server's signing
11264 key is authorized. It also reports the size of the compressed archives
11265 (``nars'') provided by the server, the size the corresponding store
11266 items occupy in the store (assuming deduplication is turned off), and
11267 the server's throughput. The second part gives continuous integration
11268 (CI) statistics, if the server supports it. In addition, using the
11269 @option{--coverage} option, @command{guix weather} can list ``important''
11270 package substitutes missing on the server (see below).
11272 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
11273 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
11274 challenge}, it ignores signatures on those substitutes, which is
11275 innocuous since the command only gathers statistics and cannot install
11278 The general syntax is:
11281 guix weather @var{options}@dots{} [@var{packages}@dots{}]
11284 When @var{packages} is omitted, @command{guix weather} checks the availability
11285 of substitutes for @emph{all} the packages, or for those specified with
11286 @option{--manifest}; otherwise it only considers the specified packages. It
11287 is also possible to query specific system types with @option{--system}.
11288 @command{guix weather} exits with a non-zero code when the fraction of
11289 available substitutes is below 100%.
11291 The available options are listed below.
11294 @item --substitute-urls=@var{urls}
11295 @var{urls} is the space-separated list of substitute server URLs to
11296 query. When this option is omitted, the default set of substitute
11297 servers is queried.
11299 @item --system=@var{system}
11300 @itemx -s @var{system}
11301 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
11302 option can be repeated, in which case @command{guix weather} will query
11303 substitutes for several system types.
11305 @item --manifest=@var{file}
11306 Instead of querying substitutes for all the packages, only ask for those
11307 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
11308 with the @code{-m} option of @command{guix package} (@pxref{Invoking
11311 This option can be repeated several times, in which case the manifests
11314 @item --coverage[=@var{count}]
11315 @itemx -c [@var{count}]
11316 Report on substitute coverage for packages: list packages with at least
11317 @var{count} dependents (zero by default) for which substitutes are
11318 unavailable. Dependent packages themselves are not listed: if @var{b} depends
11319 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
11320 @var{b} usually lacks substitutes as well. The result looks like this:
11323 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
11324 computing 8,983 package derivations for x86_64-linux...
11325 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
11326 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
11327 @value{SUBSTITUTE-URL}
11328 64.7% substitutes available (6,047 out of 9,343)
11330 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
11331 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
11332 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
11333 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
11337 What this example shows is that @code{kcoreaddons} and presumably the 58
11338 packages that depend on it have no substitutes at @code{ci.guix.info};
11339 likewise for @code{qgpgme} and the 46 packages that depend on it.
11341 If you are a Guix developer, or if you are taking care of this build farm,
11342 you'll probably want to have a closer look at these packages: they may simply
11345 @item --display-missing
11346 Display the list of store items for which substitutes are missing.
11349 @node Invoking guix processes
11350 @section Invoking @command{guix processes}
11352 The @command{guix processes} command can be useful to developers and system
11353 administrators, especially on multi-user machines and on build farms: it lists
11354 the current sessions (connections to the daemon), as well as information about
11355 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
11356 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
11357 listed.}. Here's an example of the information it returns:
11360 $ sudo guix processes
11363 ClientCommand: guix environment --ad-hoc python
11367 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
11371 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
11372 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
11373 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
11374 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
11375 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
11376 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
11377 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
11380 In this example we see that @command{guix-daemon} has three clients:
11381 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
11382 integration tool; their process identifier (PID) is given by the
11383 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
11384 @command{guix-daemon} sub-process of this particular session.
11386 The @code{LockHeld} fields show which store items are currently locked by this
11387 session, which corresponds to store items being built or substituted (the
11388 @code{LockHeld} field is not displayed when @command{guix processes} is not
11389 running as root). Last, by looking at the @code{ChildProcess} field, we
11390 understand that these three builds are being offloaded (@pxref{Daemon Offload
11393 The output is in Recutils format so we can use the handy @command{recsel}
11394 command to select sessions of interest (@pxref{Selection Expressions,,,
11395 recutils, GNU recutils manual}). As an example, the command shows the command
11396 line and PID of the client that triggered the build of a Perl package:
11399 $ sudo guix processes | \
11400 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
11402 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
11405 @node System Configuration
11406 @chapter System Configuration
11408 @cindex system configuration
11409 Guix System supports a consistent whole-system configuration
11410 mechanism. By that we mean that all aspects of the global system
11411 configuration---such as the available system services, timezone and
11412 locale settings, user accounts---are declared in a single place. Such
11413 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
11415 One of the advantages of putting all the system configuration under the
11416 control of Guix is that it supports transactional system upgrades, and
11417 makes it possible to roll back to a previous system instantiation,
11418 should something go wrong with the new one (@pxref{Features}). Another
11419 advantage is that it makes it easy to replicate the exact same configuration
11420 across different machines, or at different points in time, without
11421 having to resort to additional administration tools layered on top of
11422 the own tools of the system.
11423 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
11425 This section describes this mechanism. First we focus on the system
11426 administrator's viewpoint---explaining how the system is configured and
11427 instantiated. Then we show how this mechanism can be extended, for
11428 instance to support new system services.
11431 * Using the Configuration System:: Customizing your GNU system.
11432 * operating-system Reference:: Detail of operating-system declarations.
11433 * File Systems:: Configuring file system mounts.
11434 * Mapped Devices:: Block device extra processing.
11435 * User Accounts:: Specifying user accounts.
11436 * Keyboard Layout:: How the system interprets key strokes.
11437 * Locales:: Language and cultural convention settings.
11438 * Services:: Specifying system services.
11439 * Setuid Programs:: Programs running with root privileges.
11440 * X.509 Certificates:: Authenticating HTTPS servers.
11441 * Name Service Switch:: Configuring libc's name service switch.
11442 * Initial RAM Disk:: Linux-Libre bootstrapping.
11443 * Bootloader Configuration:: Configuring the boot loader.
11444 * Invoking guix system:: Instantiating a system configuration.
11445 * Invoking guix deploy:: Deploying a system configuration to a remote host.
11446 * Running Guix in a VM:: How to run Guix System in a virtual machine.
11447 * Defining Services:: Adding new service definitions.
11450 @node Using the Configuration System
11451 @section Using the Configuration System
11453 The operating system is configured by providing an
11454 @code{operating-system} declaration in a file that can then be passed to
11455 the @command{guix system} command (@pxref{Invoking guix system}). A
11456 simple setup, with the default system services, the default Linux-Libre
11457 kernel, initial RAM disk, and boot loader looks like this:
11459 @findex operating-system
11461 @include os-config-bare-bones.texi
11464 This example should be self-describing. Some of the fields defined
11465 above, such as @code{host-name} and @code{bootloader}, are mandatory.
11466 Others, such as @code{packages} and @code{services}, can be omitted, in
11467 which case they get a default value.
11469 Below we discuss the effect of some of the most important fields
11470 (@pxref{operating-system Reference}, for details about all the available
11471 fields), and how to @dfn{instantiate} the operating system using
11472 @command{guix system}.
11474 @unnumberedsubsec Bootloader
11476 @cindex legacy boot, on Intel machines
11477 @cindex BIOS boot, on Intel machines
11480 The @code{bootloader} field describes the method that will be used to boot
11481 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
11482 mode, as in the example above. However, more recent machines rely instead on
11483 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
11484 the @code{bootloader} field should contain something along these lines:
11487 (bootloader-configuration
11488 (bootloader grub-efi-bootloader)
11489 (target "/boot/efi"))
11492 @xref{Bootloader Configuration}, for more information on the available
11493 configuration options.
11495 @unnumberedsubsec Globally-Visible Packages
11497 @vindex %base-packages
11498 The @code{packages} field lists packages that will be globally visible
11499 on the system, for all user accounts---i.e., in every user's @env{PATH}
11500 environment variable---in addition to the per-user profiles
11501 (@pxref{Invoking guix package}). The @code{%base-packages} variable
11502 provides all the tools one would expect for basic user and administrator
11503 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
11504 the GNU Zile lightweight text editor, @command{find}, @command{grep},
11505 etc. The example above adds GNU@tie{}Screen to those,
11506 taken from the @code{(gnu packages screen)}
11507 module (@pxref{Package Modules}). The
11508 @code{(list package output)} syntax can be used to add a specific output
11512 (use-modules (gnu packages))
11513 (use-modules (gnu packages dns))
11517 (packages (cons (list bind "utils")
11521 @findex specification->package
11522 Referring to packages by variable name, like @code{bind} above, has
11523 the advantage of being unambiguous; it also allows typos and such to be
11524 diagnosed right away as ``unbound variables''. The downside is that one
11525 needs to know which module defines which package, and to augment the
11526 @code{use-package-modules} line accordingly. To avoid that, one can use
11527 the @code{specification->package} procedure of the @code{(gnu packages)}
11528 module, which returns the best package for a given name or name and
11532 (use-modules (gnu packages))
11536 (packages (append (map specification->package
11537 '("tcpdump" "htop" "gnupg@@2.0"))
11541 @unnumberedsubsec System Services
11544 @vindex %base-services
11545 The @code{services} field lists @dfn{system services} to be made
11546 available when the system starts (@pxref{Services}).
11547 The @code{operating-system} declaration above specifies that, in
11548 addition to the basic services, we want the OpenSSH secure shell
11549 daemon listening on port 2222 (@pxref{Networking Services,
11550 @code{openssh-service-type}}). Under the hood,
11551 @code{openssh-service-type} arranges so that @command{sshd} is started with the
11552 right command-line options, possibly with supporting configuration files
11553 generated as needed (@pxref{Defining Services}).
11555 @cindex customization, of services
11556 @findex modify-services
11557 Occasionally, instead of using the base services as is, you will want to
11558 customize them. To do this, use @code{modify-services} (@pxref{Service
11559 Reference, @code{modify-services}}) to modify the list.
11561 For example, suppose you want to modify @code{guix-daemon} and Mingetty
11562 (the console log-in) in the @code{%base-services} list (@pxref{Base
11563 Services, @code{%base-services}}). To do that, you can write the
11564 following in your operating system declaration:
11567 (define %my-services
11568 ;; My very own list of services.
11569 (modify-services %base-services
11570 (guix-service-type config =>
11571 (guix-configuration
11573 (use-substitutes? #f)
11574 (extra-options '("--gc-keep-derivations"))))
11575 (mingetty-service-type config =>
11576 (mingetty-configuration
11577 (inherit config)))))
11581 (services %my-services))
11584 This changes the configuration---i.e., the service parameters---of the
11585 @code{guix-service-type} instance, and that of all the
11586 @code{mingetty-service-type} instances in the @code{%base-services} list.
11587 Observe how this is accomplished: first, we arrange for the original
11588 configuration to be bound to the identifier @code{config} in the
11589 @var{body}, and then we write the @var{body} so that it evaluates to the
11590 desired configuration. In particular, notice how we use @code{inherit}
11591 to create a new configuration which has the same values as the old
11592 configuration, but with a few modifications.
11594 @cindex encrypted disk
11595 The configuration for a typical ``desktop'' usage, with an encrypted
11596 root partition, the X11 display
11597 server, GNOME and Xfce (users can choose which of these desktop
11598 environments to use at the log-in screen by pressing @kbd{F1}), network
11599 management, power management, and more, would look like this:
11602 @include os-config-desktop.texi
11605 A graphical system with a choice of lightweight window managers
11606 instead of full-blown desktop environments would look like this:
11609 @include os-config-lightweight-desktop.texi
11612 This example refers to the @file{/boot/efi} file system by its UUID,
11613 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
11614 as returned by the @command{blkid} command.
11616 @xref{Desktop Services}, for the exact list of services provided by
11617 @code{%desktop-services}. @xref{X.509 Certificates}, for background
11618 information about the @code{nss-certs} package that is used here.
11620 Again, @code{%desktop-services} is just a list of service objects. If
11621 you want to remove services from there, you can do so using the
11622 procedures for list filtering (@pxref{SRFI-1 Filtering and
11623 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
11624 following expression returns a list that contains all the services in
11625 @code{%desktop-services} minus the Avahi service:
11628 (remove (lambda (service)
11629 (eq? (service-kind service) avahi-service-type))
11633 @unnumberedsubsec Instantiating the System
11635 Assuming the @code{operating-system} declaration
11636 is stored in the @file{my-system-config.scm}
11637 file, the @command{guix system reconfigure my-system-config.scm} command
11638 instantiates that configuration, and makes it the default GRUB boot
11639 entry (@pxref{Invoking guix system}).
11641 The normal way to change the system configuration is by updating this
11642 file and re-running @command{guix system reconfigure}. One should never
11643 have to touch files in @file{/etc} or to run commands that modify the
11644 system state such as @command{useradd} or @command{grub-install}. In
11645 fact, you must avoid that since that would not only void your warranty
11646 but also prevent you from rolling back to previous versions of your
11647 system, should you ever need to.
11649 @cindex roll-back, of the operating system
11650 Speaking of roll-back, each time you run @command{guix system
11651 reconfigure}, a new @dfn{generation} of the system is created---without
11652 modifying or deleting previous generations. Old system generations get
11653 an entry in the bootloader boot menu, allowing you to boot them in case
11654 something went wrong with the latest generation. Reassuring, no? The
11655 @command{guix system list-generations} command lists the system
11656 generations available on disk. It is also possible to roll back the
11657 system via the commands @command{guix system roll-back} and
11658 @command{guix system switch-generation}.
11660 Although the @command{guix system reconfigure} command will not modify
11661 previous generations, you must take care when the current generation is not
11662 the latest (e.g., after invoking @command{guix system roll-back}), since
11663 the operation might overwrite a later generation (@pxref{Invoking guix
11666 @unnumberedsubsec The Programming Interface
11668 At the Scheme level, the bulk of an @code{operating-system} declaration
11669 is instantiated with the following monadic procedure (@pxref{The Store
11672 @deffn {Monadic Procedure} operating-system-derivation os
11673 Return a derivation that builds @var{os}, an @code{operating-system}
11674 object (@pxref{Derivations}).
11676 The output of the derivation is a single directory that refers to all
11677 the packages, configuration files, and other supporting files needed to
11678 instantiate @var{os}.
11681 This procedure is provided by the @code{(gnu system)} module. Along
11682 with @code{(gnu services)} (@pxref{Services}), this module contains the
11683 guts of Guix System. Make sure to visit it!
11686 @node operating-system Reference
11687 @section @code{operating-system} Reference
11689 This section summarizes all the options available in
11690 @code{operating-system} declarations (@pxref{Using the Configuration
11693 @deftp {Data Type} operating-system
11694 This is the data type representing an operating system configuration.
11695 By that, we mean all the global system configuration, not per-user
11696 configuration (@pxref{Using the Configuration System}).
11699 @item @code{kernel} (default: @code{linux-libre})
11700 The package object of the operating system kernel to
11701 use@footnote{Currently only the Linux-libre kernel is fully supported.
11702 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
11703 available when building a virtual machine disk image.}.
11706 @item @code{hurd} (default: @code{#f})
11707 The package object of the hurd to be started by the kernel. When this
11708 field is set, produce a GNU/Hurd operating system. In that case,
11709 @code{kernel} must also be set to the @code{gnumach} package---the
11710 microkernel the Hurd runs on.
11713 This feature is experimental and only supported for disk images.
11716 @item @code{kernel-loadable-modules} (default: '())
11717 A list of objects (usually packages) to collect loadable kernel modules
11718 from--e.g. @code{(list ddcci-driver-linux)}.
11720 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
11721 List of strings or gexps representing additional arguments to pass on
11722 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
11724 @item @code{bootloader}
11725 The system bootloader configuration object. @xref{Bootloader Configuration}.
11728 This is the label (a string) as it appears in the bootloader's menu entry.
11729 The default label includes the kernel name and version.
11731 @item @code{keyboard-layout} (default: @code{#f})
11732 This field specifies the keyboard layout to use in the console. It can be
11733 either @code{#f}, in which case the default keyboard layout is used (usually
11734 US English), or a @code{<keyboard-layout>} record.
11736 This keyboard layout is in effect as soon as the kernel has booted. For
11737 instance, it is the keyboard layout in effect when you type a passphrase if
11738 your root file system is on a @code{luks-device-mapping} mapped device
11739 (@pxref{Mapped Devices}).
11742 This does @emph{not} specify the keyboard layout used by the bootloader, nor
11743 that used by the graphical display server. @xref{Bootloader Configuration},
11744 for information on how to specify the bootloader's keyboard layout. @xref{X
11745 Window}, for information on how to specify the keyboard layout used by the X
11749 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
11751 @cindex initial RAM disk
11752 The list of Linux kernel modules that need to be available in the
11753 initial RAM disk. @xref{Initial RAM Disk}.
11755 @item @code{initrd} (default: @code{base-initrd})
11756 A procedure that returns an initial RAM disk for the Linux
11757 kernel. This field is provided to support low-level customization and
11758 should rarely be needed for casual use. @xref{Initial RAM Disk}.
11760 @item @code{firmware} (default: @code{%base-firmware})
11762 List of firmware packages loadable by the operating system kernel.
11764 The default includes firmware needed for Atheros- and Broadcom-based
11765 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
11766 respectively). @xref{Hardware Considerations}, for more info on
11767 supported hardware.
11769 @item @code{host-name}
11772 @item @code{hosts-file}
11774 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
11775 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
11776 Reference Manual}). The default is a file with entries for
11777 @code{localhost} and @var{host-name}.
11779 @item @code{mapped-devices} (default: @code{'()})
11780 A list of mapped devices. @xref{Mapped Devices}.
11782 @item @code{file-systems}
11783 A list of file systems. @xref{File Systems}.
11785 @item @code{swap-devices} (default: @code{'()})
11786 @cindex swap devices
11787 A list of strings identifying devices or files to be used for ``swap
11788 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
11789 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
11790 It is possible to specify a swap file in a file system on a mapped
11791 device, provided that the necessary device mapping and file system are
11792 also specified. @xref{Mapped Devices} and @ref{File Systems}.
11794 @item @code{users} (default: @code{%base-user-accounts})
11795 @itemx @code{groups} (default: @code{%base-groups})
11796 List of user accounts and groups. @xref{User Accounts}.
11798 If the @code{users} list lacks a user account with UID@tie{}0, a
11799 ``root'' account with UID@tie{}0 is automatically added.
11801 @item @code{skeletons} (default: @code{(default-skeletons)})
11802 A list target file name/file-like object tuples (@pxref{G-Expressions,
11803 file-like objects}). These are the skeleton files that will be added to
11804 the home directory of newly-created user accounts.
11806 For instance, a valid value may look like this:
11809 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
11810 (".guile" ,(plain-file "guile"
11811 "(use-modules (ice-9 readline))
11812 (activate-readline)")))
11815 @item @code{issue} (default: @code{%default-issue})
11816 A string denoting the contents of the @file{/etc/issue} file, which is
11817 displayed when users log in on a text console.
11819 @item @code{packages} (default: @code{%base-packages})
11820 The set of packages installed in the global profile, which is accessible
11821 at @file{/run/current-system/profile}.
11823 The default set includes core utilities and it is good practice to
11824 install non-core utilities in user profiles (@pxref{Invoking guix
11827 @item @code{timezone}
11828 A timezone identifying string---e.g., @code{"Europe/Paris"}.
11830 You can run the @command{tzselect} command to find out which timezone
11831 string corresponds to your region. Choosing an invalid timezone name
11832 causes @command{guix system} to fail.
11834 @item @code{locale} (default: @code{"en_US.utf8"})
11835 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
11836 Library Reference Manual}). @xref{Locales}, for more information.
11838 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
11839 The list of locale definitions to be compiled and that may be used at
11840 run time. @xref{Locales}.
11842 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
11843 The list of GNU@tie{}libc packages whose locale data and tools are used
11844 to build the locale definitions. @xref{Locales}, for compatibility
11845 considerations that justify this option.
11847 @item @code{name-service-switch} (default: @code{%default-nss})
11848 Configuration of the libc name service switch (NSS)---a
11849 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
11852 @item @code{services} (default: @code{%base-services})
11853 A list of service objects denoting system services. @xref{Services}.
11855 @cindex essential services
11856 @item @code{essential-services} (default: ...)
11857 The list of ``essential services''---i.e., things like instances of
11858 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
11859 Reference}), which are derived from the operating system definition itself.
11860 As a user you should @emph{never} need to touch this field.
11862 @item @code{pam-services} (default: @code{(base-pam-services)})
11864 @cindex pluggable authentication modules
11865 Linux @dfn{pluggable authentication module} (PAM) services.
11866 @c FIXME: Add xref to PAM services section.
11868 @item @code{setuid-programs} (default: @code{%setuid-programs})
11869 List of string-valued G-expressions denoting setuid programs.
11870 @xref{Setuid Programs}.
11872 @item @code{sudoers-file} (default: @code{%sudoers-specification})
11873 @cindex sudoers file
11874 The contents of the @file{/etc/sudoers} file as a file-like object
11875 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
11877 This file specifies which users can use the @command{sudo} command, what
11878 they are allowed to do, and what privileges they may gain. The default
11879 is that only @code{root} and members of the @code{wheel} group may use
11884 @deffn {Scheme Syntax} this-operating-system
11885 When used in the @emph{lexical scope} of an operating system field definition,
11886 this identifier resolves to the operating system being defined.
11888 The example below shows how to refer to the operating system being defined in
11889 the definition of the @code{label} field:
11892 (use-modules (gnu) (guix))
11896 (label (package-full-name
11897 (operating-system-kernel this-operating-system))))
11900 It is an error to refer to @code{this-operating-system} outside an operating
11907 @section File Systems
11909 The list of file systems to be mounted is specified in the
11910 @code{file-systems} field of the operating system declaration
11911 (@pxref{Using the Configuration System}). Each file system is declared
11912 using the @code{file-system} form, like this:
11916 (mount-point "/home")
11917 (device "/dev/sda3")
11921 As usual, some of the fields are mandatory---those shown in the example
11922 above---while others can be omitted. These are described below.
11924 @deftp {Data Type} file-system
11925 Objects of this type represent file systems to be mounted. They
11926 contain the following members:
11930 This is a string specifying the type of the file system---e.g.,
11933 @item @code{mount-point}
11934 This designates the place where the file system is to be mounted.
11936 @item @code{device}
11937 This names the ``source'' of the file system. It can be one of three
11938 things: a file system label, a file system UUID, or the name of a
11939 @file{/dev} node. Labels and UUIDs offer a way to refer to file
11940 systems without having to hard-code their actual device
11941 name@footnote{Note that, while it is tempting to use
11942 @file{/dev/disk/by-uuid} and similar device names to achieve the same
11943 result, this is not recommended: These special device nodes are created
11944 by the udev daemon and may be unavailable at the time the device is
11947 @findex file-system-label
11948 File system labels are created using the @code{file-system-label}
11949 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
11950 plain strings. Here's an example of a file system referred to by its
11951 label, as shown by the @command{e2label} command:
11955 (mount-point "/home")
11957 (device (file-system-label "my-home")))
11961 UUIDs are converted from their string representation (as shown by the
11962 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
11963 @code{uuid} form expects 16-byte UUIDs as defined in
11964 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
11965 form of UUID used by the ext2 family of file systems and others, but it
11966 is different from ``UUIDs'' found in FAT file systems, for instance.},
11971 (mount-point "/home")
11973 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
11976 When the source of a file system is a mapped device (@pxref{Mapped
11977 Devices}), its @code{device} field @emph{must} refer to the mapped
11978 device name---e.g., @file{"/dev/mapper/root-partition"}.
11979 This is required so that
11980 the system knows that mounting the file system depends on having the
11981 corresponding device mapping established.
11983 @item @code{flags} (default: @code{'()})
11984 This is a list of symbols denoting mount flags. Recognized flags
11985 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
11986 access to special files), @code{no-suid} (ignore setuid and setgid
11987 bits), @code{no-atime} (do not update file access times),
11988 @code{strict-atime} (update file access time), @code{lazy-time} (only
11989 update time on the in-memory version of the file inode), and
11990 @code{no-exec} (disallow program execution).
11991 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
11992 Manual}, for more information on these flags.
11994 @item @code{options} (default: @code{#f})
11995 This is either @code{#f}, or a string denoting mount options passed to
11996 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
11997 Library Reference Manual}, for details and run @command{man 8 mount} for
11998 options for various file systems. Note that the
11999 @code{file-system-options->alist} and @code{alist->file-system-options}
12000 procedures from @code{(gnu system file-systems)} can be used to convert
12001 file system options given as an association list to the string
12002 representation, and vice-versa.
12004 @item @code{mount?} (default: @code{#t})
12005 This value indicates whether to automatically mount the file system when
12006 the system is brought up. When set to @code{#f}, the file system gets
12007 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
12008 is not automatically mounted.
12010 @item @code{needed-for-boot?} (default: @code{#f})
12011 This Boolean value indicates whether the file system is needed when
12012 booting. If that is true, then the file system is mounted when the
12013 initial RAM disk (initrd) is loaded. This is always the case, for
12014 instance, for the root file system.
12016 @item @code{check?} (default: @code{#t})
12017 This Boolean indicates whether the file system needs to be checked for
12018 errors before being mounted.
12020 @item @code{create-mount-point?} (default: @code{#f})
12021 When true, the mount point is created if it does not exist yet.
12023 @item @code{dependencies} (default: @code{'()})
12024 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
12025 representing file systems that must be mounted or mapped devices that
12026 must be opened before (and unmounted or closed after) this one.
12028 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
12029 a dependency of @file{/sys/fs/cgroup/cpu} and
12030 @file{/sys/fs/cgroup/memory}.
12032 Another example is a file system that depends on a mapped device, for
12033 example for an encrypted partition (@pxref{Mapped Devices}).
12037 The @code{(gnu system file-systems)} exports the following useful
12040 @defvr {Scheme Variable} %base-file-systems
12041 These are essential file systems that are required on normal systems,
12042 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
12043 below). Operating system declarations should always contain at least
12047 @defvr {Scheme Variable} %pseudo-terminal-file-system
12048 This is the file system to be mounted as @file{/dev/pts}. It supports
12049 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
12050 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
12051 Manual}). Pseudo-terminals are used by terminal emulators such as
12055 @defvr {Scheme Variable} %shared-memory-file-system
12056 This file system is mounted as @file{/dev/shm} and is used to support
12057 memory sharing across processes (@pxref{Memory-mapped I/O,
12058 @code{shm_open},, libc, The GNU C Library Reference Manual}).
12061 @defvr {Scheme Variable} %immutable-store
12062 This file system performs a read-only ``bind mount'' of
12063 @file{/gnu/store}, making it read-only for all the users including
12064 @code{root}. This prevents against accidental modification by software
12065 running as @code{root} or by system administrators.
12067 The daemon itself is still able to write to the store: it remounts it
12068 read-write in its own ``name space.''
12071 @defvr {Scheme Variable} %binary-format-file-system
12072 The @code{binfmt_misc} file system, which allows handling of arbitrary
12073 executable file types to be delegated to user space. This requires the
12074 @code{binfmt.ko} kernel module to be loaded.
12077 @defvr {Scheme Variable} %fuse-control-file-system
12078 The @code{fusectl} file system, which allows unprivileged users to mount
12079 and unmount user-space FUSE file systems. This requires the
12080 @code{fuse.ko} kernel module to be loaded.
12083 @node Btrfs file system
12084 @subsection Btrfs file system
12086 The Btrfs has special features, such as subvolumes, that merit being
12087 explained in more details. The following section attempts to cover
12088 basic as well as complex uses of a Btrfs file system with the Guix
12091 In its simplest usage, a Btrfs file system can be described, for
12096 (mount-point "/home")
12098 (device (file-system-label "my-home")))
12101 The example below is more complex, as it makes use of a Btrfs
12102 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
12103 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
12104 dependency on @code{mapped-devices}):
12108 (device (file-system-label "my-btrfs-pool"))
12111 (options "subvol=rootfs")
12112 (dependencies mapped-devices))
12115 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
12116 top level during the early boot, and rely on their configuration to
12117 refer to the correct subvolume path within that top level. The
12118 bootloaders operating in this way typically produce their configuration
12119 on a running system where the Btrfs partitions are already mounted and
12120 where the subvolume information is readily available. As an example,
12121 @command{grub-mkconfig}, the configuration generator command shipped
12122 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
12123 path of a subvolume.
12125 The Guix System produces a bootloader configuration using the operating
12126 system configuration as its sole input; it is therefore necessary to
12127 extract the subvolume name on which @file{/gnu/store} lives (if any)
12128 from that operating system configuration. To better illustrate,
12129 consider a subvolume named 'rootfs' which contains the root file system
12130 data. In such situation, the GRUB bootloader would only see the top
12131 level of the root Btrfs partition, e.g.:
12135 ├── rootfs (subvolume directory)
12136 ├── gnu (normal directory)
12137 ├── store (normal directory)
12141 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
12142 of the kernel, initrd binaries and any other files referred to in the
12143 GRUB configuration that must be found during the early boot.
12145 The next example shows a nested hierarchy of subvolumes and
12150 ├── rootfs (subvolume)
12151 ├── gnu (normal directory)
12152 ├── store (subvolume)
12156 This scenario would work without mounting the 'store' subvolume.
12157 Mounting 'rootfs' is sufficient, since the subvolume name matches its
12158 intended mount point in the file system hierarchy. Alternatively, the
12159 'store' subvolume could be referred to by setting the @code{subvol}
12160 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
12162 Finally, a more contrived example of nested subvolumes:
12166 ├── root-snapshots (subvolume)
12167 ├── root-current (subvolume)
12168 ├── guix-store (subvolume)
12172 Here, the 'guix-store' subvolume doesn't match its intended mount point,
12173 so it is necessary to mount it. The subvolume must be fully specified,
12174 by passing its file name to the @code{subvol} option. To illustrate,
12175 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
12176 a file system declaration such as:
12180 (device (file-system-label "btrfs-pool-1"))
12181 (mount-point "/gnu/store")
12183 (options "subvol=root-snapshots/root-current/guix-store,\
12184 compress-force=zstd,space_cache=v2"))
12187 @node Mapped Devices
12188 @section Mapped Devices
12190 @cindex device mapping
12191 @cindex mapped devices
12192 The Linux kernel has a notion of @dfn{device mapping}: a block device,
12193 such as a hard disk partition, can be @dfn{mapped} into another device,
12194 usually in @code{/dev/mapper/},
12195 with additional processing over the data that flows through
12196 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
12197 concept of a ``mapped device'' and that of a file system: both boil down
12198 to @emph{translating} input/output operations made on a file to
12199 operations on its backing store. Thus, the Hurd implements mapped
12200 devices, like file systems, using the generic @dfn{translator} mechanism
12201 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
12202 typical example is encryption device mapping: all writes to the mapped
12203 device are encrypted, and all reads are deciphered, transparently.
12204 Guix extends this notion by considering any device or set of devices that
12205 are @dfn{transformed} in some way to create a new device; for instance,
12206 RAID devices are obtained by @dfn{assembling} several other devices, such
12207 as hard disks or partitions, into a new one that behaves as one partition.
12208 Other examples, not yet implemented, are LVM logical volumes.
12210 Mapped devices are declared using the @code{mapped-device} form,
12211 defined as follows; for examples, see below.
12213 @deftp {Data Type} mapped-device
12214 Objects of this type represent device mappings that will be made when
12215 the system boots up.
12219 This is either a string specifying the name of the block device to be mapped,
12220 such as @code{"/dev/sda3"}, or a list of such strings when several devices
12221 need to be assembled for creating a new one.
12224 This string specifies the name of the resulting mapped device. For
12225 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
12226 specifying @code{"my-partition"} leads to the creation of
12227 the @code{"/dev/mapper/my-partition"} device.
12228 For RAID devices of type @code{raid-device-mapping}, the full device name
12229 such as @code{"/dev/md0"} needs to be given.
12232 This must be a @code{mapped-device-kind} object, which specifies how
12233 @var{source} is mapped to @var{target}.
12237 @defvr {Scheme Variable} luks-device-mapping
12238 This defines LUKS block device encryption using the @command{cryptsetup}
12239 command from the package with the same name. It relies on the
12240 @code{dm-crypt} Linux kernel module.
12243 @defvr {Scheme Variable} raid-device-mapping
12244 This defines a RAID device, which is assembled using the @code{mdadm}
12245 command from the package with the same name. It requires a Linux kernel
12246 module for the appropriate RAID level to be loaded, such as @code{raid456}
12247 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
12250 @cindex disk encryption
12252 The following example specifies a mapping from @file{/dev/sda3} to
12253 @file{/dev/mapper/home} using LUKS---the
12254 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
12255 standard mechanism for disk encryption.
12256 The @file{/dev/mapper/home}
12257 device can then be used as the @code{device} of a @code{file-system}
12258 declaration (@pxref{File Systems}).
12262 (source "/dev/sda3")
12264 (type luks-device-mapping))
12267 Alternatively, to become independent of device numbering, one may obtain
12268 the LUKS UUID (@dfn{unique identifier}) of the source device by a
12272 cryptsetup luksUUID /dev/sda3
12275 and use it as follows:
12279 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
12281 (type luks-device-mapping))
12284 @cindex swap encryption
12285 It is also desirable to encrypt swap space, since swap space may contain
12286 sensitive data. One way to accomplish that is to use a swap file in a
12287 file system on a device mapped via LUKS encryption. In this way, the
12288 swap file is encrypted because the entire device is encrypted.
12289 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
12291 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
12292 may be declared as follows:
12296 (source (list "/dev/sda1" "/dev/sdb1"))
12297 (target "/dev/md0")
12298 (type raid-device-mapping))
12301 The @file{/dev/md0} device can then be used as the @code{device} of a
12302 @code{file-system} declaration (@pxref{File Systems}).
12303 Note that the RAID level need not be given; it is chosen during the
12304 initial creation and formatting of the RAID device and is determined
12305 automatically later.
12308 @node User Accounts
12309 @section User Accounts
12313 @cindex user accounts
12314 User accounts and groups are entirely managed through the
12315 @code{operating-system} declaration. They are specified with the
12316 @code{user-account} and @code{user-group} forms:
12322 (supplementary-groups '("wheel" ;allow use of sudo, etc.
12323 "audio" ;sound card
12324 "video" ;video devices such as webcams
12325 "cdrom")) ;the good ol' CD-ROM
12326 (comment "Bob's sister")
12327 (home-directory "/home/alice"))
12330 When booting or upon completion of @command{guix system reconfigure},
12331 the system ensures that only the user accounts and groups specified in
12332 the @code{operating-system} declaration exist, and with the specified
12333 properties. Thus, account or group creations or modifications made by
12334 directly invoking commands such as @command{useradd} are lost upon
12335 reconfiguration or reboot. This ensures that the system remains exactly
12338 @deftp {Data Type} user-account
12339 Objects of this type represent user accounts. The following members may
12344 The name of the user account.
12348 This is the name (a string) or identifier (a number) of the user group
12349 this account belongs to.
12351 @item @code{supplementary-groups} (default: @code{'()})
12352 Optionally, this can be defined as a list of group names that this
12353 account belongs to.
12355 @item @code{uid} (default: @code{#f})
12356 This is the user ID for this account (a number), or @code{#f}. In the
12357 latter case, a number is automatically chosen by the system when the
12358 account is created.
12360 @item @code{comment} (default: @code{""})
12361 A comment about the account, such as the account owner's full name.
12363 @item @code{home-directory}
12364 This is the name of the home directory for the account.
12366 @item @code{create-home-directory?} (default: @code{#t})
12367 Indicates whether the home directory of this account should be created
12368 if it does not exist yet.
12370 @item @code{shell} (default: Bash)
12371 This is a G-expression denoting the file name of a program to be used as
12372 the shell (@pxref{G-Expressions}).
12374 @item @code{system?} (default: @code{#f})
12375 This Boolean value indicates whether the account is a ``system''
12376 account. System accounts are sometimes treated specially; for instance,
12377 graphical login managers do not list them.
12379 @anchor{user-account-password}
12380 @cindex password, for user accounts
12381 @item @code{password} (default: @code{#f})
12382 You would normally leave this field to @code{#f}, initialize user
12383 passwords as @code{root} with the @command{passwd} command, and then let
12384 users change it with @command{passwd}. Passwords set with
12385 @command{passwd} are of course preserved across reboot and
12388 If you @emph{do} want to set an initial password for an account, then
12389 this field must contain the encrypted password, as a string. You can use the
12390 @code{crypt} procedure for this purpose:
12397 ;; Specify a SHA-512-hashed initial password.
12398 (password (crypt "InitialPassword!" "$6$abc")))
12402 The hash of this initial password will be available in a file in
12403 @file{/gnu/store}, readable by all the users, so this method must be used with
12407 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
12408 more information on password encryption, and @ref{Encryption,,, guile, GNU
12409 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
12415 User group declarations are even simpler:
12418 (user-group (name "students"))
12421 @deftp {Data Type} user-group
12422 This type is for, well, user groups. There are just a few fields:
12426 The name of the group.
12428 @item @code{id} (default: @code{#f})
12429 The group identifier (a number). If @code{#f}, a new number is
12430 automatically allocated when the group is created.
12432 @item @code{system?} (default: @code{#f})
12433 This Boolean value indicates whether the group is a ``system'' group.
12434 System groups have low numerical IDs.
12436 @item @code{password} (default: @code{#f})
12437 What, user groups can have a password? Well, apparently yes. Unless
12438 @code{#f}, this field specifies the password of the group.
12443 For convenience, a variable lists all the basic user groups one may
12446 @defvr {Scheme Variable} %base-groups
12447 This is the list of basic user groups that users and/or packages expect
12448 to be present on the system. This includes groups such as ``root'',
12449 ``wheel'', and ``users'', as well as groups used to control access to
12450 specific devices such as ``audio'', ``disk'', and ``cdrom''.
12453 @defvr {Scheme Variable} %base-user-accounts
12454 This is the list of basic system accounts that programs may expect to
12455 find on a GNU/Linux system, such as the ``nobody'' account.
12457 Note that the ``root'' account is not included here. It is a
12458 special-case and is automatically added whether or not it is specified.
12461 @node Keyboard Layout
12462 @section Keyboard Layout
12464 @cindex keyboard layout
12466 To specify what each key of your keyboard does, you need to tell the operating
12467 system what @dfn{keyboard layout} you want to use. The default, when nothing
12468 is specified, is the US English QWERTY layout for 105-key PC keyboards.
12469 However, German speakers will usually prefer the German QWERTZ layout, French
12470 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
12471 or bépo, and they might even want to further customize the effect of some of
12472 the keys. This section explains how to get that done.
12474 @cindex keyboard layout, definition
12475 There are three components that will want to know about your keyboard layout:
12479 The @emph{bootloader} may want to know what keyboard layout you want to use
12480 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
12481 you want, for instance, to make sure that you can type the passphrase of your
12482 encrypted root partition using the right layout.
12485 The @emph{operating system kernel}, Linux, will need that so that the console
12486 is properly configured (@pxref{operating-system Reference,
12487 @code{keyboard-layout}}).
12490 The @emph{graphical display server}, usually Xorg, also has its own idea of
12491 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
12494 Guix allows you to configure all three separately but, fortunately, it allows
12495 you to share the same keyboard layout for all three components.
12497 @cindex XKB, keyboard layouts
12498 Keyboard layouts are represented by records created by the
12499 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
12500 the X Keyboard extension (XKB), each layout has four attributes: a name (often
12501 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
12502 optional variant name, an optional keyboard model name, and a possibly empty
12503 list of additional options. In most cases the layout name is all you care
12504 about. Here are a few example:
12507 ;; The German QWERTZ layout. Here we assume a standard
12508 ;; "pc105" keyboard model.
12509 (keyboard-layout "de")
12511 ;; The bépo variant of the French layout.
12512 (keyboard-layout "fr" "bepo")
12514 ;; The Catalan layout.
12515 (keyboard-layout "es" "cat")
12517 ;; Arabic layout with "Alt-Shift" to switch to US layout.
12518 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
12520 ;; The Latin American Spanish layout. In addition, the
12521 ;; "Caps Lock" key is used as an additional "Ctrl" key,
12522 ;; and the "Menu" key is used as a "Compose" key to enter
12523 ;; accented letters.
12524 (keyboard-layout "latam"
12525 #:options '("ctrl:nocaps" "compose:menu"))
12527 ;; The Russian layout for a ThinkPad keyboard.
12528 (keyboard-layout "ru" #:model "thinkpad")
12530 ;; The "US international" layout, which is the US layout plus
12531 ;; dead keys to enter accented characters. This is for an
12532 ;; Apple MacBook keyboard.
12533 (keyboard-layout "us" "intl" #:model "macbook78")
12536 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
12537 for a complete list of supported layouts, variants, and models.
12539 @cindex keyboard layout, configuration
12540 Let's say you want your system to use the Turkish keyboard layout throughout
12541 your system---bootloader, console, and Xorg. Here's what your system
12542 configuration would look like:
12544 @findex set-xorg-configuration
12546 ;; Using the Turkish layout for the bootloader, the console,
12551 (keyboard-layout (keyboard-layout "tr")) ;for the console
12552 (bootloader (bootloader-configuration
12553 (bootloader grub-efi-bootloader)
12554 (target "/boot/efi")
12555 (keyboard-layout keyboard-layout))) ;for GRUB
12556 (services (cons (set-xorg-configuration
12557 (xorg-configuration ;for Xorg
12558 (keyboard-layout keyboard-layout)))
12559 %desktop-services)))
12562 In the example above, for GRUB and for Xorg, we just refer to the
12563 @code{keyboard-layout} field defined above, but we could just as well refer to
12564 a different layout. The @code{set-xorg-configuration} procedure communicates
12565 the desired Xorg configuration to the graphical log-in manager, by default
12568 We've discussed how to specify the @emph{default} keyboard layout of your
12569 system when it starts, but you can also adjust it at run time:
12573 If you're using GNOME, its settings panel has a ``Region & Language'' entry
12574 where you can select one or more keyboard layouts.
12577 Under Xorg, the @command{setxkbmap} command (from the same-named package)
12578 allows you to change the current layout. For example, this is how you would
12579 change the layout to US Dvorak:
12582 setxkbmap us dvorak
12586 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
12587 console. However, note that @code{loadkeys} does @emph{not} use the XKB
12588 keyboard layout categorization described above. The command below loads the
12589 French bépo layout:
12600 A @dfn{locale} defines cultural conventions for a particular language
12601 and region of the world (@pxref{Locales,,, libc, The GNU C Library
12602 Reference Manual}). Each locale has a name that typically has the form
12603 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
12604 @code{fr_LU.utf8} designates the locale for the French language, with
12605 cultural conventions from Luxembourg, and using the UTF-8 encoding.
12607 @cindex locale definition
12608 Usually, you will want to specify the default locale for the machine
12609 using the @code{locale} field of the @code{operating-system} declaration
12610 (@pxref{operating-system Reference, @code{locale}}).
12612 The selected locale is automatically added to the @dfn{locale
12613 definitions} known to the system if needed, with its codeset inferred
12614 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
12615 @code{UTF-8} codeset. Additional locale definitions can be specified in
12616 the @code{locale-definitions} slot of @code{operating-system}---this is
12617 useful, for instance, if the codeset could not be inferred from the
12618 locale name. The default set of locale definitions includes some widely
12619 used locales, but not all the available locales, in order to save space.
12621 For instance, to add the North Frisian locale for Germany, the value of
12625 (cons (locale-definition
12626 (name "fy_DE.utf8") (source "fy_DE"))
12627 %default-locale-definitions)
12630 Likewise, to save space, one might want @code{locale-definitions} to
12631 list only the locales that are actually used, as in:
12634 (list (locale-definition
12635 (name "ja_JP.eucjp") (source "ja_JP")
12636 (charset "EUC-JP")))
12640 The compiled locale definitions are available at
12641 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
12642 version, which is the default location where the GNU@tie{}libc provided
12643 by Guix looks for locale data. This can be overridden using the
12644 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
12645 @env{LOCPATH} and locale packages}).
12647 The @code{locale-definition} form is provided by the @code{(gnu system
12648 locale)} module. Details are given below.
12650 @deftp {Data Type} locale-definition
12651 This is the data type of a locale definition.
12656 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
12657 Reference Manual}, for more information on locale names.
12659 @item @code{source}
12660 The name of the source for that locale. This is typically the
12661 @code{@var{language}_@var{territory}} part of the locale name.
12663 @item @code{charset} (default: @code{"UTF-8"})
12664 The ``character set'' or ``code set'' for that locale,
12665 @uref{https://www.iana.org/assignments/character-sets, as defined by
12671 @defvr {Scheme Variable} %default-locale-definitions
12672 A list of commonly used UTF-8 locales, used as the default
12673 value of the @code{locale-definitions} field of @code{operating-system}
12676 @cindex locale name
12677 @cindex normalized codeset in locale names
12678 These locale definitions use the @dfn{normalized codeset} for the part
12679 that follows the dot in the name (@pxref{Using gettextized software,
12680 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
12681 instance it has @code{uk_UA.utf8} but @emph{not}, say,
12682 @code{uk_UA.UTF-8}.
12685 @subsection Locale Data Compatibility Considerations
12687 @cindex incompatibility, of locale data
12688 @code{operating-system} declarations provide a @code{locale-libcs} field
12689 to specify the GNU@tie{}libc packages that are used to compile locale
12690 declarations (@pxref{operating-system Reference}). ``Why would I
12691 care?'', you may ask. Well, it turns out that the binary format of
12692 locale data is occasionally incompatible from one libc version to
12695 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
12696 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
12697 For instance, a program linked against libc version 2.21 is unable to
12698 read locale data produced with libc 2.22; worse, that program
12699 @emph{aborts} instead of simply ignoring the incompatible locale
12700 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
12701 the incompatible locale data, which is already an improvement.}.
12702 Similarly, a program linked against libc 2.22 can read most, but not
12703 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
12704 data is incompatible); thus calls to @code{setlocale} may fail, but
12705 programs will not abort.
12707 The ``problem'' with Guix is that users have a lot of freedom: They can
12708 choose whether and when to upgrade software in their profiles, and might
12709 be using a libc version different from the one the system administrator
12710 used to build the system-wide locale data.
12712 Fortunately, unprivileged users can also install their own locale data
12713 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
12714 @env{GUIX_LOCPATH} and locale packages}).
12716 Still, it is best if the system-wide locale data at
12717 @file{/run/current-system/locale} is built for all the libc versions
12718 actually in use on the system, so that all the programs can access
12719 it---this is especially crucial on a multi-user system. To do that, the
12720 administrator can specify several libc packages in the
12721 @code{locale-libcs} field of @code{operating-system}:
12724 (use-package-modules base)
12728 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
12731 This example would lead to a system containing locale definitions for
12732 both libc 2.21 and the current version of libc in
12733 @file{/run/current-system/locale}.
12739 @cindex system services
12740 An important part of preparing an @code{operating-system} declaration is
12741 listing @dfn{system services} and their configuration (@pxref{Using the
12742 Configuration System}). System services are typically daemons launched
12743 when the system boots, or other actions needed at that time---e.g.,
12744 configuring network access.
12746 Guix has a broad definition of ``service'' (@pxref{Service
12747 Composition}), but many services are managed by the GNU@tie{}Shepherd
12748 (@pxref{Shepherd Services}). On a running system, the @command{herd}
12749 command allows you to list the available services, show their status,
12750 start and stop them, or do other specific operations (@pxref{Jump
12751 Start,,, shepherd, The GNU Shepherd Manual}). For example:
12757 The above command, run as @code{root}, lists the currently defined
12758 services. The @command{herd doc} command shows a synopsis of the given
12759 service and its associated actions:
12763 Run libc's name service cache daemon (nscd).
12765 # herd doc nscd action invalidate
12766 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
12769 The @command{start}, @command{stop}, and @command{restart} sub-commands
12770 have the effect you would expect. For instance, the commands below stop
12771 the nscd service and restart the Xorg display server:
12775 Service nscd has been stopped.
12776 # herd restart xorg-server
12777 Service xorg-server has been stopped.
12778 Service xorg-server has been started.
12781 The following sections document the available services, starting with
12782 the core services, that may be used in an @code{operating-system}
12786 * Base Services:: Essential system services.
12787 * Scheduled Job Execution:: The mcron service.
12788 * Log Rotation:: The rottlog service.
12789 * Networking Services:: Network setup, SSH daemon, etc.
12790 * X Window:: Graphical display.
12791 * Printing Services:: Local and remote printer support.
12792 * Desktop Services:: D-Bus and desktop services.
12793 * Sound Services:: ALSA and Pulseaudio services.
12794 * Database Services:: SQL databases, key-value stores, etc.
12795 * Mail Services:: IMAP, POP3, SMTP, and all that.
12796 * Messaging Services:: Messaging services.
12797 * Telephony Services:: Telephony services.
12798 * Monitoring Services:: Monitoring services.
12799 * Kerberos Services:: Kerberos services.
12800 * LDAP Services:: LDAP services.
12801 * Web Services:: Web servers.
12802 * Certificate Services:: TLS certificates via Let's Encrypt.
12803 * DNS Services:: DNS daemons.
12804 * VPN Services:: VPN daemons.
12805 * Network File System:: NFS related services.
12806 * Continuous Integration:: The Cuirass service.
12807 * Power Management Services:: Extending battery life.
12808 * Audio Services:: The MPD.
12809 * Virtualization Services:: Virtualization services.
12810 * Version Control Services:: Providing remote access to Git repositories.
12811 * Game Services:: Game servers.
12812 * PAM Mount Service:: Service to mount volumes when logging in.
12813 * Guix Services:: Services relating specifically to Guix.
12814 * Linux Services:: Services tied to the Linux kernel.
12815 * Hurd Services:: Services specific for a Hurd System.
12816 * Miscellaneous Services:: Other services.
12819 @node Base Services
12820 @subsection Base Services
12822 The @code{(gnu services base)} module provides definitions for the basic
12823 services that one expects from the system. The services exported by
12824 this module are listed below.
12826 @defvr {Scheme Variable} %base-services
12827 This variable contains a list of basic services (@pxref{Service Types
12828 and Services}, for more information on service objects) one would
12829 expect from the system: a login service (mingetty) on each tty, syslogd,
12830 the libc name service cache daemon (nscd), the udev device manager, and
12833 This is the default value of the @code{services} field of
12834 @code{operating-system} declarations. Usually, when customizing a
12835 system, you will want to append services to @code{%base-services}, like
12839 (append (list (service avahi-service-type)
12840 (service openssh-service-type))
12845 @defvr {Scheme Variable} special-files-service-type
12846 This is the service that sets up ``special files'' such as
12847 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
12849 The value associated with @code{special-files-service-type} services
12850 must be a list of tuples where the first element is the ``special file''
12851 and the second element is its target. By default it is:
12853 @cindex @file{/bin/sh}
12854 @cindex @file{sh}, in @file{/bin}
12856 `(("/bin/sh" ,(file-append bash "/bin/sh")))
12859 @cindex @file{/usr/bin/env}
12860 @cindex @file{env}, in @file{/usr/bin}
12861 If you want to add, say, @code{/usr/bin/env} to your system, you can
12865 `(("/bin/sh" ,(file-append bash "/bin/sh"))
12866 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
12869 Since this is part of @code{%base-services}, you can use
12870 @code{modify-services} to customize the set of special files
12871 (@pxref{Service Reference, @code{modify-services}}). But the simple way
12872 to add a special file is @i{via} the @code{extra-special-file} procedure
12876 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
12877 Use @var{target} as the ``special file'' @var{file}.
12879 For example, adding the following lines to the @code{services} field of
12880 your operating system declaration leads to a @file{/usr/bin/env}
12884 (extra-special-file "/usr/bin/env"
12885 (file-append coreutils "/bin/env"))
12889 @deffn {Scheme Procedure} host-name-service @var{name}
12890 Return a service that sets the host name to @var{name}.
12893 @defvr {Scheme Variable} console-font-service-type
12894 Install the given fonts on the specified ttys (fonts are per
12895 virtual console on the kernel Linux). The value of this service is a list of
12896 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
12897 package or any valid argument to @command{setfont}, as in this example:
12900 `(("tty1" . "LatGrkCyr-8x16")
12901 ("tty2" . ,(file-append
12903 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
12904 ("tty3" . ,(file-append
12906 "/share/consolefonts/ter-132n"))) ; for HDPI
12910 @deffn {Scheme Procedure} login-service @var{config}
12911 Return a service to run login according to @var{config}, a
12912 @code{<login-configuration>} object, which specifies the message of the day,
12913 among other things.
12916 @deftp {Data Type} login-configuration
12917 This is the data type representing the configuration of login.
12922 @cindex message of the day
12923 A file-like object containing the ``message of the day''.
12925 @item @code{allow-empty-passwords?} (default: @code{#t})
12926 Allow empty passwords by default so that first-time users can log in when
12927 the 'root' account has just been created.
12932 @deffn {Scheme Procedure} mingetty-service @var{config}
12933 Return a service to run mingetty according to @var{config}, a
12934 @code{<mingetty-configuration>} object, which specifies the tty to run, among
12938 @deftp {Data Type} mingetty-configuration
12939 This is the data type representing the configuration of Mingetty, which
12940 provides the default implementation of virtual console log-in.
12945 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
12947 @item @code{auto-login} (default: @code{#f})
12948 When true, this field must be a string denoting the user name under
12949 which the system automatically logs in. When it is @code{#f}, a
12950 user name and password must be entered to log in.
12952 @item @code{login-program} (default: @code{#f})
12953 This must be either @code{#f}, in which case the default log-in program
12954 is used (@command{login} from the Shadow tool suite), or a gexp denoting
12955 the name of the log-in program.
12957 @item @code{login-pause?} (default: @code{#f})
12958 When set to @code{#t} in conjunction with @var{auto-login}, the user
12959 will have to press a key before the log-in shell is launched.
12961 @item @code{mingetty} (default: @var{mingetty})
12962 The Mingetty package to use.
12967 @deffn {Scheme Procedure} agetty-service @var{config}
12968 Return a service to run agetty according to @var{config}, an
12969 @code{<agetty-configuration>} object, which specifies the tty to run,
12970 among other things.
12973 @deftp {Data Type} agetty-configuration
12974 This is the data type representing the configuration of agetty, which
12975 implements virtual and serial console log-in. See the @code{agetty(8)}
12976 man page for more information.
12981 The name of the console this agetty runs on, as a string---e.g.,
12982 @code{"ttyS0"}. This argument is optional, it will default to
12983 a reasonable default serial port used by the kernel Linux.
12985 For this, if there is a value for an option @code{agetty.tty} in the kernel
12986 command line, agetty will extract the device name of the serial port
12987 from it and use that.
12989 If not and if there is a value for an option @code{console} with a tty in
12990 the Linux command line, agetty will extract the device name of the
12991 serial port from it and use that.
12993 In both cases, agetty will leave the other serial device settings
12994 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
12997 @item @code{baud-rate} (default: @code{#f})
12998 A string containing a comma-separated list of one or more baud rates, in
13001 @item @code{term} (default: @code{#f})
13002 A string containing the value used for the @env{TERM} environment
13005 @item @code{eight-bits?} (default: @code{#f})
13006 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
13009 @item @code{auto-login} (default: @code{#f})
13010 When passed a login name, as a string, the specified user will be logged
13011 in automatically without prompting for their login name or password.
13013 @item @code{no-reset?} (default: @code{#f})
13014 When @code{#t}, don't reset terminal cflags (control modes).
13016 @item @code{host} (default: @code{#f})
13017 This accepts a string containing the ``login_host'', which will be written
13018 into the @file{/var/run/utmpx} file.
13020 @item @code{remote?} (default: @code{#f})
13021 When set to @code{#t} in conjunction with @var{host}, this will add an
13022 @code{-r} fakehost option to the command line of the login program
13023 specified in @var{login-program}.
13025 @item @code{flow-control?} (default: @code{#f})
13026 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
13028 @item @code{no-issue?} (default: @code{#f})
13029 When set to @code{#t}, the contents of the @file{/etc/issue} file will
13030 not be displayed before presenting the login prompt.
13032 @item @code{init-string} (default: @code{#f})
13033 This accepts a string that will be sent to the tty or modem before
13034 sending anything else. It can be used to initialize a modem.
13036 @item @code{no-clear?} (default: @code{#f})
13037 When set to @code{#t}, agetty will not clear the screen before showing
13040 @item @code{login-program} (default: (file-append shadow "/bin/login"))
13041 This must be either a gexp denoting the name of a log-in program, or
13042 unset, in which case the default value is the @command{login} from the
13045 @item @code{local-line} (default: @code{#f})
13046 Control the CLOCAL line flag. This accepts one of three symbols as
13047 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
13048 the default value chosen by agetty is @code{'auto}.
13050 @item @code{extract-baud?} (default: @code{#f})
13051 When set to @code{#t}, instruct agetty to try to extract the baud rate
13052 from the status messages produced by certain types of modems.
13054 @item @code{skip-login?} (default: @code{#f})
13055 When set to @code{#t}, do not prompt the user for a login name. This
13056 can be used with @var{login-program} field to use non-standard login
13059 @item @code{no-newline?} (default: @code{#f})
13060 When set to @code{#t}, do not print a newline before printing the
13061 @file{/etc/issue} file.
13063 @c Is this dangerous only when used with login-program, or always?
13064 @item @code{login-options} (default: @code{#f})
13065 This option accepts a string containing options that are passed to the
13066 login program. When used with the @var{login-program}, be aware that a
13067 malicious user could try to enter a login name containing embedded
13068 options that could be parsed by the login program.
13070 @item @code{login-pause} (default: @code{#f})
13071 When set to @code{#t}, wait for any key before showing the login prompt.
13072 This can be used in conjunction with @var{auto-login} to save memory by
13073 lazily spawning shells.
13075 @item @code{chroot} (default: @code{#f})
13076 Change root to the specified directory. This option accepts a directory
13079 @item @code{hangup?} (default: @code{#f})
13080 Use the Linux system call @code{vhangup} to do a virtual hangup of the
13081 specified terminal.
13083 @item @code{keep-baud?} (default: @code{#f})
13084 When set to @code{#t}, try to keep the existing baud rate. The baud
13085 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
13088 @item @code{timeout} (default: @code{#f})
13089 When set to an integer value, terminate if no user name could be read
13090 within @var{timeout} seconds.
13092 @item @code{detect-case?} (default: @code{#f})
13093 When set to @code{#t}, turn on support for detecting an uppercase-only
13094 terminal. This setting will detect a login name containing only
13095 uppercase letters as indicating an uppercase-only terminal and turn on
13096 some upper-to-lower case conversions. Note that this will not support
13097 Unicode characters.
13099 @item @code{wait-cr?} (default: @code{#f})
13100 When set to @code{#t}, wait for the user or modem to send a
13101 carriage-return or linefeed character before displaying
13102 @file{/etc/issue} or login prompt. This is typically used with the
13103 @var{init-string} option.
13105 @item @code{no-hints?} (default: @code{#f})
13106 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
13109 @item @code{no-hostname?} (default: @code{#f})
13110 By default, the hostname is printed. When this option is set to
13111 @code{#t}, no hostname will be shown at all.
13113 @item @code{long-hostname?} (default: @code{#f})
13114 By default, the hostname is only printed until the first dot. When this
13115 option is set to @code{#t}, the fully qualified hostname by
13116 @code{gethostname} or @code{getaddrinfo} is shown.
13118 @item @code{erase-characters} (default: @code{#f})
13119 This option accepts a string of additional characters that should be
13120 interpreted as backspace when the user types their login name.
13122 @item @code{kill-characters} (default: @code{#f})
13123 This option accepts a string that should be interpreted to mean ``ignore
13124 all previous characters'' (also called a ``kill'' character) when the user
13125 types their login name.
13127 @item @code{chdir} (default: @code{#f})
13128 This option accepts, as a string, a directory path that will be changed
13131 @item @code{delay} (default: @code{#f})
13132 This options accepts, as an integer, the number of seconds to sleep
13133 before opening the tty and displaying the login prompt.
13135 @item @code{nice} (default: @code{#f})
13136 This option accepts, as an integer, the nice value with which to run the
13137 @command{login} program.
13139 @item @code{extra-options} (default: @code{'()})
13140 This option provides an ``escape hatch'' for the user to provide arbitrary
13141 command-line arguments to @command{agetty} as a list of strings.
13146 @deffn {Scheme Procedure} kmscon-service-type @var{config}
13147 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
13148 according to @var{config}, a @code{<kmscon-configuration>} object, which
13149 specifies the tty to run, among other things.
13152 @deftp {Data Type} kmscon-configuration
13153 This is the data type representing the configuration of Kmscon, which
13154 implements virtual console log-in.
13158 @item @code{virtual-terminal}
13159 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
13161 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
13162 A gexp denoting the name of the log-in program. The default log-in program is
13163 @command{login} from the Shadow tool suite.
13165 @item @code{login-arguments} (default: @code{'("-p")})
13166 A list of arguments to pass to @command{login}.
13168 @item @code{auto-login} (default: @code{#f})
13169 When passed a login name, as a string, the specified user will be logged
13170 in automatically without prompting for their login name or password.
13172 @item @code{hardware-acceleration?} (default: #f)
13173 Whether to use hardware acceleration.
13175 @item @code{kmscon} (default: @var{kmscon})
13176 The Kmscon package to use.
13181 @cindex name service cache daemon
13183 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
13184 [#:name-services '()]
13185 Return a service that runs the libc name service cache daemon (nscd) with the
13186 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
13187 Service Switch}, for an example.
13189 For convenience, the Shepherd service for nscd provides the following actions:
13193 @cindex cache invalidation, nscd
13194 @cindex nscd, cache invalidation
13195 This invalidate the given cache. For instance, running:
13198 herd invalidate nscd hosts
13202 invalidates the host name lookup cache of nscd.
13205 Running @command{herd statistics nscd} displays information about nscd usage
13211 @defvr {Scheme Variable} %nscd-default-configuration
13212 This is the default @code{<nscd-configuration>} value (see below) used
13213 by @code{nscd-service}. It uses the caches defined by
13214 @code{%nscd-default-caches}; see below.
13217 @deftp {Data Type} nscd-configuration
13218 This is the data type representing the name service cache daemon (nscd)
13223 @item @code{name-services} (default: @code{'()})
13224 List of packages denoting @dfn{name services} that must be visible to
13225 the nscd---e.g., @code{(list @var{nss-mdns})}.
13227 @item @code{glibc} (default: @var{glibc})
13228 Package object denoting the GNU C Library providing the @command{nscd}
13231 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
13232 Name of the nscd log file. This is where debugging output goes when
13233 @code{debug-level} is strictly positive.
13235 @item @code{debug-level} (default: @code{0})
13236 Integer denoting the debugging levels. Higher numbers mean that more
13237 debugging output is logged.
13239 @item @code{caches} (default: @code{%nscd-default-caches})
13240 List of @code{<nscd-cache>} objects denoting things to be cached; see
13246 @deftp {Data Type} nscd-cache
13247 Data type representing a cache database of nscd and its parameters.
13251 @item @code{database}
13252 This is a symbol representing the name of the database to be cached.
13253 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
13254 @code{services}, which designate the corresponding NSS database
13255 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
13257 @item @code{positive-time-to-live}
13258 @itemx @code{negative-time-to-live} (default: @code{20})
13259 A number representing the number of seconds during which a positive or
13260 negative lookup result remains in cache.
13262 @item @code{check-files?} (default: @code{#t})
13263 Whether to check for updates of the files corresponding to
13266 For instance, when @var{database} is @code{hosts}, setting this flag
13267 instructs nscd to check for updates in @file{/etc/hosts} and to take
13270 @item @code{persistent?} (default: @code{#t})
13271 Whether the cache should be stored persistently on disk.
13273 @item @code{shared?} (default: @code{#t})
13274 Whether the cache should be shared among users.
13276 @item @code{max-database-size} (default: 32@tie{}MiB)
13277 Maximum size in bytes of the database cache.
13279 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
13280 @c settings, so leave them out.
13285 @defvr {Scheme Variable} %nscd-default-caches
13286 List of @code{<nscd-cache>} objects used by default by
13287 @code{nscd-configuration} (see above).
13289 It enables persistent and aggressive caching of service and host name
13290 lookups. The latter provides better host name lookup performance,
13291 resilience in the face of unreliable name servers, and also better
13292 privacy---often the result of host name lookups is in local cache, so
13293 external name servers do not even need to be queried.
13296 @anchor{syslog-configuration-type}
13299 @deftp {Data Type} syslog-configuration
13300 This data type represents the configuration of the syslog daemon.
13303 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
13304 The syslog daemon to use.
13306 @item @code{config-file} (default: @code{%default-syslog.conf})
13307 The syslog configuration file to use.
13312 @anchor{syslog-service}
13314 @deffn {Scheme Procedure} syslog-service @var{config}
13315 Return a service that runs a syslog daemon according to @var{config}.
13317 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
13318 information on the configuration file syntax.
13321 @defvr {Scheme Variable} guix-service-type
13322 This is the type of the service that runs the build daemon,
13323 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
13324 @code{guix-configuration} record as described below.
13327 @anchor{guix-configuration-type}
13328 @deftp {Data Type} guix-configuration
13329 This data type represents the configuration of the Guix build daemon.
13330 @xref{Invoking guix-daemon}, for more information.
13333 @item @code{guix} (default: @var{guix})
13334 The Guix package to use.
13336 @item @code{build-group} (default: @code{"guixbuild"})
13337 Name of the group for build user accounts.
13339 @item @code{build-accounts} (default: @code{10})
13340 Number of build user accounts to create.
13342 @item @code{authorize-key?} (default: @code{#t})
13343 @cindex substitutes, authorization thereof
13344 Whether to authorize the substitute keys listed in
13345 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
13346 (@pxref{Substitutes}).
13348 @vindex %default-authorized-guix-keys
13349 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
13350 The list of authorized key files for archive imports, as a list of
13351 string-valued gexps (@pxref{Invoking guix archive}). By default, it
13352 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
13354 @item @code{use-substitutes?} (default: @code{#t})
13355 Whether to use substitutes.
13357 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
13358 The list of URLs where to look for substitutes by default.
13360 @item @code{max-silent-time} (default: @code{0})
13361 @itemx @code{timeout} (default: @code{0})
13362 The number of seconds of silence and the number of seconds of activity,
13363 respectively, after which a build process times out. A value of zero
13364 disables the timeout.
13366 @item @code{log-compression} (default: @code{'bzip2})
13367 The type of compression used for build logs---one of @code{gzip},
13368 @code{bzip2}, or @code{none}.
13370 @item @code{extra-options} (default: @code{'()})
13371 List of extra command-line options for @command{guix-daemon}.
13373 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
13374 File where @command{guix-daemon}'s standard output and standard error
13377 @cindex HTTP proxy, for @code{guix-daemon}
13378 @cindex proxy, for @code{guix-daemon} HTTP access
13379 @item @code{http-proxy} (default: @code{#f})
13380 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
13381 derivations and substitutes.
13383 It is also possible to change the daemon's proxy at run time through the
13384 @code{set-http-proxy} action, which restarts it:
13387 herd set-http-proxy guix-daemon http://localhost:8118
13390 To clear the proxy settings, run:
13393 herd set-http-proxy guix-daemon
13396 @item @code{tmpdir} (default: @code{#f})
13397 A directory path where the @command{guix-daemon} will perform builds.
13402 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
13403 Run @var{udev}, which populates the @file{/dev} directory dynamically.
13404 udev rules can be provided as a list of files through the @var{rules}
13405 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
13406 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
13407 creation of such rule files.
13409 The @command{herd rules udev} command, as root, returns the name of the
13410 directory containing all the active udev rules.
13413 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
13414 Return a udev-rule file named @var{file-name} containing the rules
13415 defined by the @var{contents} literal.
13417 In the following example, a rule for a USB device is defined to be
13418 stored in the file @file{90-usb-thing.rules}. The rule runs a script
13419 upon detecting a USB device with a given product identifier.
13422 (define %example-udev-rule
13424 "90-usb-thing.rules"
13425 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
13426 "ATTR@{product@}==\"Example\", "
13427 "RUN+=\"/path/to/script\"")))
13431 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
13432 [#:groups @var{groups}]
13433 Return a service that extends @code{udev-service-type } with @var{rules}
13434 and @code{account-service-type} with @var{groups} as system groups.
13435 This works by creating a singleton service type
13436 @code{@var{name}-udev-rules}, of which the returned service is an
13439 Here we show how it can be used to extend @code{udev-service-type} with the
13440 previously defined rule @code{%example-udev-rule}.
13446 (cons (udev-rules-service 'usb-thing %example-udev-rule)
13447 %desktop-services)))
13451 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
13452 Return a udev file named @var{file-name} containing the rules defined
13453 within @var{file}, a file-like object.
13455 The following example showcases how we can use an existing rule file.
13458 (use-modules (guix download) ;for url-fetch
13459 (guix packages) ;for origin
13462 (define %android-udev-rules
13464 "51-android-udev.rules"
13465 (let ((version "20170910"))
13468 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
13469 "android-udev-rules/" version "/51-android.rules"))
13471 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
13475 Additionally, Guix package definitions can be included in @var{rules} in
13476 order to extend the udev rules with the definitions found under their
13477 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
13478 @var{file->udev-rule} example, we could have used the
13479 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
13480 packages android)} module.
13482 The following example shows how to use the @var{android-udev-rules}
13483 package so that the Android tool @command{adb} can detect devices
13484 without root privileges. It also details how to create the
13485 @code{adbusers} group, which is required for the proper functioning of
13486 the rules defined within the @code{android-udev-rules} package. To
13487 create such a group, we must define it both as part of the
13488 @code{supplementary-groups} of our @code{user-account} declaration, as
13489 well as in the @var{groups} of the @code{udev-rules-service} procedure.
13492 (use-modules (gnu packages android) ;for android-udev-rules
13493 (gnu system shadow) ;for user-group
13498 (users (cons (user-account
13500 (supplementary-groups
13501 '("adbusers" ;for adb
13502 "wheel" "netdev" "audio" "video")))))
13505 (cons (udev-rules-service 'android android-udev-rules
13506 #:groups '("adbusers"))
13507 %desktop-services)))
13510 @defvr {Scheme Variable} urandom-seed-service-type
13511 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
13512 when rebooting. It also tries to seed @file{/dev/urandom} from
13513 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
13517 @defvr {Scheme Variable} %random-seed-file
13518 This is the name of the file where some random bytes are saved by
13519 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
13520 It defaults to @file{/var/lib/random-seed}.
13525 @defvr {Scheme Variable} gpm-service-type
13526 This is the type of the service that runs GPM, the @dfn{general-purpose
13527 mouse daemon}, which provides mouse support to the Linux console. GPM
13528 allows users to use the mouse in the console, notably to select, copy,
13531 The value for services of this type must be a @code{gpm-configuration}
13532 (see below). This service is not part of @code{%base-services}.
13535 @deftp {Data Type} gpm-configuration
13536 Data type representing the configuration of GPM.
13539 @item @code{options} (default: @code{%default-gpm-options})
13540 Command-line options passed to @command{gpm}. The default set of
13541 options instruct @command{gpm} to listen to mouse events on
13542 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
13545 @item @code{gpm} (default: @code{gpm})
13546 The GPM package to use.
13551 @anchor{guix-publish-service-type}
13552 @deffn {Scheme Variable} guix-publish-service-type
13553 This is the service type for @command{guix publish} (@pxref{Invoking
13554 guix publish}). Its value must be a @code{guix-publish-configuration}
13555 object, as described below.
13557 This assumes that @file{/etc/guix} already contains a signing key pair as
13558 created by @command{guix archive --generate-key} (@pxref{Invoking guix
13559 archive}). If that is not the case, the service will fail to start.
13562 @deftp {Data Type} guix-publish-configuration
13563 Data type representing the configuration of the @code{guix publish}
13567 @item @code{guix} (default: @code{guix})
13568 The Guix package to use.
13570 @item @code{port} (default: @code{80})
13571 The TCP port to listen for connections.
13573 @item @code{host} (default: @code{"localhost"})
13574 The host (and thus, network interface) to listen to. Use
13575 @code{"0.0.0.0"} to listen on all the network interfaces.
13577 @item @code{compression} (default: @code{'(("gzip" 3))})
13578 This is a list of compression method/level tuple used when compressing
13579 substitutes. For example, to compress all substitutes with @emph{both} lzip
13580 at level 7 and gzip at level 9, write:
13583 '(("lzip" 7) ("gzip" 9))
13586 Level 9 achieves the best compression ratio at the expense of increased CPU
13587 usage, whereas level 1 achieves fast compression.
13589 An empty list disables compression altogether.
13591 @item @code{nar-path} (default: @code{"nar"})
13592 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
13593 publish, @option{--nar-path}}, for details.
13595 @item @code{cache} (default: @code{#f})
13596 When it is @code{#f}, disable caching and instead generate archives on
13597 demand. Otherwise, this should be the name of a directory---e.g.,
13598 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
13599 archives and meta-data ready to be sent. @xref{Invoking guix publish,
13600 @option{--cache}}, for more information on the tradeoffs involved.
13602 @item @code{workers} (default: @code{#f})
13603 When it is an integer, this is the number of worker threads used for
13604 caching; when @code{#f}, the number of processors is used.
13605 @xref{Invoking guix publish, @option{--workers}}, for more information.
13607 @item @code{ttl} (default: @code{#f})
13608 When it is an integer, this denotes the @dfn{time-to-live} in seconds
13609 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
13610 for more information.
13614 @anchor{rngd-service}
13615 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
13616 [#:device "/dev/hwrng"]
13617 Return a service that runs the @command{rngd} program from @var{rng-tools}
13618 to add @var{device} to the kernel's entropy pool. The service will fail if
13619 @var{device} does not exist.
13622 @anchor{pam-limits-service}
13623 @cindex session limits
13628 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
13630 Return a service that installs a configuration file for the
13631 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
13632 @code{pam_limits} module}. The procedure optionally takes a list of
13633 @code{pam-limits-entry} values, which can be used to specify
13634 @code{ulimit} limits and nice priority limits to user sessions.
13636 The following limits definition sets two hard and soft limits for all
13637 login sessions of users in the @code{realtime} group:
13640 (pam-limits-service
13642 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
13643 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
13646 The first entry increases the maximum realtime priority for
13647 non-privileged processes; the second entry lifts any restriction of the
13648 maximum address space that can be locked in memory. These settings are
13649 commonly used for real-time audio systems.
13652 @node Scheduled Job Execution
13653 @subsection Scheduled Job Execution
13657 @cindex scheduling jobs
13658 The @code{(gnu services mcron)} module provides an interface to
13659 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
13660 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
13661 Unix @command{cron} daemon; the main difference is that it is
13662 implemented in Guile Scheme, which provides a lot of flexibility when
13663 specifying the scheduling of jobs and their actions.
13665 The example below defines an operating system that runs the
13666 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
13667 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
13668 well as the @command{mkid} command on behalf of an unprivileged user
13669 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
13670 gexps to introduce job definitions that are passed to mcron
13671 (@pxref{G-Expressions}).
13674 (use-modules (guix) (gnu) (gnu services mcron))
13675 (use-package-modules base idutils)
13677 (define updatedb-job
13678 ;; Run 'updatedb' at 3AM every day. Here we write the
13679 ;; job's action as a Scheme procedure.
13680 #~(job '(next-hour '(3))
13682 (execl (string-append #$findutils "/bin/updatedb")
13684 "--prunepaths=/tmp /var/tmp /gnu/store"))))
13686 (define garbage-collector-job
13687 ;; Collect garbage 5 minutes after midnight every day.
13688 ;; The job's action is a shell command.
13689 #~(job "5 0 * * *" ;Vixie cron syntax
13692 (define idutils-job
13693 ;; Update the index database as user "charlie" at 12:15PM
13694 ;; and 19:15PM. This runs from the user's home directory.
13695 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
13696 (string-append #$idutils "/bin/mkid src")
13701 (services (cons (service mcron-service-type
13702 (mcron-configuration
13703 (jobs (list garbage-collector-job
13709 For more complex jobs defined in Scheme where you need control over the top
13710 level, for instance to introduce a @code{use-modules} form, you can move your
13711 code to a separate program using the @code{program-file} procedure of the
13712 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
13716 (define %battery-alert-job
13717 ;; Beep when the battery percentage falls below %MIN-LEVEL.
13719 '(next-minute (range 0 60 1))
13721 "battery-alert.scm"
13722 (with-imported-modules (source-module-closure
13723 '((guix build utils)))
13725 (define %min-level 20)
13726 (use-modules (guix build utils)
13729 (ice-9 textual-ports)
13731 (setenv "LC_ALL" "C") ;ensure English output
13732 (and-let* ((input-pipe (open-pipe*
13734 #$(file-append acpi "/bin/acpi")))
13735 (output (get-string-all input-pipe))
13736 (m (string-match "Discharging, ([0-9]+)%" output))
13737 (level (string->number (match:substring m 1)))
13738 ((< level %min-level)))
13739 (format #t "warning: Battery level is low (~a%)~%" level)
13740 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
13743 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
13744 for more information on mcron job specifications. Below is the
13745 reference of the mcron service.
13747 On a running system, you can use the @code{schedule} action of the service to
13748 visualize the mcron jobs that will be executed next:
13751 # herd schedule mcron
13755 The example above lists the next five tasks that will be executed, but you can
13756 also specify the number of tasks to display:
13759 # herd schedule mcron 10
13762 @defvr {Scheme Variable} mcron-service-type
13763 This is the type of the @code{mcron} service, whose value is an
13764 @code{mcron-configuration} object.
13766 This service type can be the target of a service extension that provides
13767 it additional job specifications (@pxref{Service Composition}). In
13768 other words, it is possible to define services that provide additional
13772 @deftp {Data Type} mcron-configuration
13773 Data type representing the configuration of mcron.
13776 @item @code{mcron} (default: @var{mcron})
13777 The mcron package to use.
13780 This is a list of gexps (@pxref{G-Expressions}), where each gexp
13781 corresponds to an mcron job specification (@pxref{Syntax, mcron job
13782 specifications,, mcron, GNU@tie{}mcron}).
13788 @subsection Log Rotation
13791 @cindex log rotation
13793 Log files such as those found in @file{/var/log} tend to grow endlessly,
13794 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
13795 their contents in separate files, possibly compressed. The @code{(gnu
13796 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
13797 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
13799 This service is part of @code{%base-services}, and thus enabled by
13800 default, with the default settings, for commonly encountered log files.
13801 The example below shows how to extend it with an additional
13802 @dfn{rotation}, should you need to do that (usually, services that
13803 produce log files already take care of that):
13806 (use-modules (guix) (gnu))
13807 (use-service-modules admin)
13809 (define my-log-files
13810 ;; Log files that I want to rotate.
13811 '("/var/log/something.log" "/var/log/another.log"))
13815 (services (cons (simple-service 'rotate-my-stuff
13816 rottlog-service-type
13817 (list (log-rotation
13819 (files my-log-files))))
13823 @defvr {Scheme Variable} rottlog-service-type
13824 This is the type of the Rottlog service, whose value is a
13825 @code{rottlog-configuration} object.
13827 Other services can extend this one with new @code{log-rotation} objects
13828 (see below), thereby augmenting the set of files to be rotated.
13830 This service type can define mcron jobs (@pxref{Scheduled Job
13831 Execution}) to run the rottlog service.
13834 @deftp {Data Type} rottlog-configuration
13835 Data type representing the configuration of rottlog.
13838 @item @code{rottlog} (default: @code{rottlog})
13839 The Rottlog package to use.
13841 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
13842 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
13843 rottlog, GNU Rot[t]log Manual}).
13845 @item @code{rotations} (default: @code{%default-rotations})
13846 A list of @code{log-rotation} objects as defined below.
13849 This is a list of gexps where each gexp corresponds to an mcron job
13850 specification (@pxref{Scheduled Job Execution}).
13854 @deftp {Data Type} log-rotation
13855 Data type representing the rotation of a group of log files.
13857 Taking an example from the Rottlog manual (@pxref{Period Related File
13858 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
13864 (files '("/var/log/apache/*"))
13865 (options '("storedir apache-archives"
13871 The list of fields is as follows:
13874 @item @code{frequency} (default: @code{'weekly})
13875 The log rotation frequency, a symbol.
13878 The list of files or file glob patterns to rotate.
13880 @item @code{options} (default: @code{'()})
13881 The list of rottlog options for this rotation (@pxref{Configuration
13882 parameters,,, rottlog, GNU Rot[t]lg Manual}).
13884 @item @code{post-rotate} (default: @code{#f})
13885 Either @code{#f} or a gexp to execute once the rotation has completed.
13889 @defvr {Scheme Variable} %default-rotations
13890 Specifies weekly rotation of @code{%rotated-files} and of
13891 @file{/var/log/guix-daemon.log}.
13894 @defvr {Scheme Variable} %rotated-files
13895 The list of syslog-controlled files to be rotated. By default it is:
13896 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
13897 "/var/log/maillog")}.
13900 @node Networking Services
13901 @subsection Networking Services
13903 The @code{(gnu services networking)} module provides services to configure
13904 the network interface.
13906 @cindex DHCP, networking service
13907 @defvr {Scheme Variable} dhcp-client-service-type
13908 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
13909 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
13910 is the DHCP client package to use, @code{isc-dhcp} by default.
13913 @deffn {Scheme Procedure} dhcpd-service-type
13914 This type defines a service that runs a DHCP daemon. To create a
13915 service of this type, you must supply a @code{<dhcpd-configuration>}.
13919 (service dhcpd-service-type
13920 (dhcpd-configuration
13921 (config-file (local-file "my-dhcpd.conf"))
13922 (interfaces '("enp0s25"))))
13926 @deftp {Data Type} dhcpd-configuration
13928 @item @code{package} (default: @code{isc-dhcp})
13929 The package that provides the DHCP daemon. This package is expected to
13930 provide the daemon at @file{sbin/dhcpd} relative to its output
13931 directory. The default package is the
13932 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
13933 @item @code{config-file} (default: @code{#f})
13934 The configuration file to use. This is required. It will be passed to
13935 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
13936 object (@pxref{G-Expressions, file-like objects}). See @code{man
13937 dhcpd.conf} for details on the configuration file syntax.
13938 @item @code{version} (default: @code{"4"})
13939 The DHCP version to use. The ISC DHCP server supports the values ``4'',
13940 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
13941 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
13943 @item @code{run-directory} (default: @code{"/run/dhcpd"})
13944 The run directory to use. At service activation time, this directory
13945 will be created if it does not exist.
13946 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
13947 The PID file to use. This corresponds to the @code{-pf} option of
13948 @code{dhcpd}. See @code{man dhcpd} for details.
13949 @item @code{interfaces} (default: @code{'()})
13950 The names of the network interfaces on which dhcpd should listen for
13951 broadcasts. If this list is not empty, then its elements (which must be
13952 strings) will be appended to the @code{dhcpd} invocation when starting
13953 the daemon. It may not be necessary to explicitly specify any
13954 interfaces here; see @code{man dhcpd} for details.
13958 @defvr {Scheme Variable} static-networking-service-type
13959 This is the type for statically-configured network interfaces.
13960 @c TODO Document <static-networking> data structures.
13963 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
13964 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
13965 [#:requirement @code{'(udev)}]
13966 Return a service that starts @var{interface} with address @var{ip}. If
13967 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
13968 it must be a string specifying the default network gateway. @var{requirement}
13969 can be used to declare a dependency on another service before configuring the
13972 This procedure can be called several times, one for each network
13973 interface of interest. Behind the scenes what it does is extend
13974 @code{static-networking-service-type} with additional network interfaces
13980 (static-networking-service "eno1" "192.168.1.82"
13981 #:gateway "192.168.1.2"
13982 #:name-servers '("192.168.1.2"))
13989 @cindex network management
13990 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
13991 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
13992 management daemon that aims to simplify wired and wireless networking.
13994 This service adds the @var{wicd} package to the global profile, providing
13995 several commands to interact with the daemon and configure networking:
13996 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
13997 and @command{wicd-curses} user interfaces.
14000 @cindex ModemManager
14002 @defvr {Scheme Variable} modem-manager-service-type
14003 This is the service type for the
14004 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
14005 service. The value for this service type is a
14006 @code{modem-manager-configuration} record.
14008 This service is part of @code{%desktop-services} (@pxref{Desktop
14012 @deftp {Data Type} modem-manager-configuration
14013 Data type representing the configuration of ModemManager.
14016 @item @code{modem-manager} (default: @code{modem-manager})
14017 The ModemManager package to use.
14022 @cindex USB_ModeSwitch
14023 @cindex Modeswitching
14025 @defvr {Scheme Variable} usb-modeswitch-service-type
14026 This is the service type for the
14027 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
14028 value for this service type is a @code{usb-modeswitch-configuration} record.
14030 When plugged in, some USB modems (and other USB devices) initially present
14031 themselves as a read-only storage medium and not as a modem. They need to be
14032 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
14033 installs udev rules to automatically modeswitch these devices when they are
14036 This service is part of @code{%desktop-services} (@pxref{Desktop
14040 @deftp {Data Type} usb-modeswitch-configuration
14041 Data type representing the configuration of USB_ModeSwitch.
14044 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
14045 The USB_ModeSwitch package providing the binaries for modeswitching.
14047 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
14048 The package providing the device data and udev rules file used by
14051 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
14052 Which config file to use for the USB_ModeSwitch dispatcher. By default the
14053 config file shipped with USB_ModeSwitch is used which disables logging to
14054 @file{/var/log} among other default settings. If set to @code{#f}, no config
14060 @cindex NetworkManager
14062 @defvr {Scheme Variable} network-manager-service-type
14063 This is the service type for the
14064 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
14065 service. The value for this service type is a
14066 @code{network-manager-configuration} record.
14068 This service is part of @code{%desktop-services} (@pxref{Desktop
14072 @deftp {Data Type} network-manager-configuration
14073 Data type representing the configuration of NetworkManager.
14076 @item @code{network-manager} (default: @code{network-manager})
14077 The NetworkManager package to use.
14079 @item @code{dns} (default: @code{"default"})
14080 Processing mode for DNS, which affects how NetworkManager uses the
14081 @code{resolv.conf} configuration file.
14085 NetworkManager will update @code{resolv.conf} to reflect the nameservers
14086 provided by currently active connections.
14089 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
14090 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
14091 then update @code{resolv.conf} to point to the local nameserver.
14093 With this setting, you can share your network connection. For example when
14094 you want to share your network connection to another laptop @i{via} an
14095 Ethernet cable, you can open @command{nm-connection-editor} and configure the
14096 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
14097 and reestablish the connection (or reboot).
14099 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
14100 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
14101 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
14102 browser on your host system, or connect to the VM @i{via} SSH
14103 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
14104 host-to-guest connection, run this command once:
14107 nmcli connection add type tun \
14108 connection.interface-name tap0 \
14109 tun.mode tap tun.owner $(id -u) \
14110 ipv4.method shared \
14111 ipv4.addresses 172.28.112.1/24
14114 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
14115 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
14116 @command{qemu-system-...}.
14119 NetworkManager will not modify @code{resolv.conf}.
14122 @item @code{vpn-plugins} (default: @code{'()})
14123 This is the list of available plugins for virtual private networks
14124 (VPNs). An example of this is the @code{network-manager-openvpn}
14125 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
14131 @deffn {Scheme Variable} connman-service-type
14132 This is the service type to run @url{https://01.org/connman,Connman},
14133 a network connection manager.
14135 Its value must be an
14136 @code{connman-configuration} record as in this example:
14139 (service connman-service-type
14140 (connman-configuration
14141 (disable-vpn? #t)))
14144 See below for details about @code{connman-configuration}.
14147 @deftp {Data Type} connman-configuration
14148 Data Type representing the configuration of connman.
14151 @item @code{connman} (default: @var{connman})
14152 The connman package to use.
14154 @item @code{disable-vpn?} (default: @code{#f})
14155 When true, disable connman's vpn plugin.
14159 @cindex WPA Supplicant
14160 @defvr {Scheme Variable} wpa-supplicant-service-type
14161 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
14162 supplicant}, an authentication daemon required to authenticate against
14163 encrypted WiFi or ethernet networks.
14166 @deftp {Data Type} wpa-supplicant-configuration
14167 Data type representing the configuration of WPA Supplicant.
14169 It takes the following parameters:
14172 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
14173 The WPA Supplicant package to use.
14175 @item @code{requirement} (default: @code{'(user-processes dbus-system loopback syslogd)}
14176 List of services that should be started before WPA Supplicant starts.
14178 @item @code{dbus?} (default: @code{#t})
14179 Whether to listen for requests on D-Bus.
14181 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
14182 Where to store the PID file.
14184 @item @code{interface} (default: @code{#f})
14185 If this is set, it must specify the name of a network interface that
14186 WPA supplicant will control.
14188 @item @code{config-file} (default: @code{#f})
14189 Optional configuration file to use.
14191 @item @code{extra-options} (default: @code{'()})
14192 List of additional command-line arguments to pass to the daemon.
14196 @cindex hostapd service, for Wi-Fi access points
14197 @cindex Wi-Fi access points, hostapd service
14198 @defvr {Scheme Variable} hostapd-service-type
14199 This is the service type to run the @uref{https://w1.fi/hostapd/,
14200 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
14201 authentication servers. Its associated value must be a
14202 @code{hostapd-configuration} as shown below:
14205 ;; Use wlan1 to run the access point for "My Network".
14206 (service hostapd-service-type
14207 (hostapd-configuration
14208 (interface "wlan1")
14209 (ssid "My Network")
14214 @deftp {Data Type} hostapd-configuration
14215 This data type represents the configuration of the hostapd service, with
14216 the following fields:
14219 @item @code{package} (default: @code{hostapd})
14220 The hostapd package to use.
14222 @item @code{interface} (default: @code{"wlan0"})
14223 The network interface to run the WiFi access point.
14226 The SSID (@dfn{service set identifier}), a string that identifies this
14229 @item @code{broadcast-ssid?} (default: @code{#t})
14230 Whether to broadcast this SSID.
14232 @item @code{channel} (default: @code{1})
14233 The WiFi channel to use.
14235 @item @code{driver} (default: @code{"nl80211"})
14236 The driver interface type. @code{"nl80211"} is used with all Linux
14237 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
14238 RADIUS server that does # not control any wireless/wired driver.
14240 @item @code{extra-settings} (default: @code{""})
14241 Extra settings to append as-is to the hostapd configuration file. See
14242 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
14243 configuration file reference.
14247 @defvr {Scheme Variable} simulated-wifi-service-type
14248 This is the type of a service to simulate WiFi networking, which can be
14249 useful in virtual machines for testing purposes. The service loads the
14251 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
14252 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
14253 network that can be seen on @code{wlan0}, by default.
14255 The service's value is a @code{hostapd-configuration} record.
14259 @defvr {Scheme Variable} iptables-service-type
14260 This is the service type to set up an iptables configuration. iptables is a
14261 packet filtering framework supported by the Linux kernel. This service
14262 supports configuring iptables for both IPv4 and IPv6. A simple example
14263 configuration rejecting all incoming connections except those to the ssh port
14267 (service iptables-service-type
14268 (iptables-configuration
14269 (ipv4-rules (plain-file "iptables.rules" "*filter
14273 -A INPUT -p tcp --dport 22 -j ACCEPT
14274 -A INPUT -j REJECT --reject-with icmp-port-unreachable
14277 (ipv6-rules (plain-file "ip6tables.rules" "*filter
14281 -A INPUT -p tcp --dport 22 -j ACCEPT
14282 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
14288 @deftp {Data Type} iptables-configuration
14289 The data type representing the configuration of iptables.
14292 @item @code{iptables} (default: @code{iptables})
14293 The iptables package that provides @code{iptables-restore} and
14294 @code{ip6tables-restore}.
14295 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
14296 The iptables rules to use. It will be passed to @code{iptables-restore}.
14297 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
14299 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
14300 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
14301 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
14307 @defvr {Scheme Variable} nftables-service-type
14308 This is the service type to set up a nftables configuration. nftables is a
14309 netfilter project that aims to replace the existing iptables, ip6tables,
14310 arptables and ebtables framework. It provides a new packet filtering
14311 framework, a new user-space utility @command{nft}, and a compatibility layer
14312 for iptables. This service comes with a default ruleset
14313 @code{%default-nftables-ruleset} that rejecting all incomming connections
14314 except those to the ssh port 22. To use it, simply write:
14317 (service nftables-service-type)
14321 @deftp {Data Type} nftables-configuration
14322 The data type representing the configuration of nftables.
14325 @item @code{package} (default: @code{nftables})
14326 The nftables package that provides @command{nft}.
14327 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
14328 The nftables ruleset to use. This may be any ``file-like'' object
14329 (@pxref{G-Expressions, file-like objects}).
14333 @cindex NTP (Network Time Protocol), service
14334 @cindex ntpd, service for the Network Time Protocol daemon
14335 @cindex real time clock
14336 @defvr {Scheme Variable} ntp-service-type
14337 This is the type of the service running the @uref{https://www.ntp.org,
14338 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
14339 system clock synchronized with that of the specified NTP servers.
14341 The value of this service is an @code{ntpd-configuration} object, as described
14345 @deftp {Data Type} ntp-configuration
14346 This is the data type for the NTP service configuration.
14349 @item @code{servers} (default: @code{%ntp-servers})
14350 This is the list of servers (@code{<ntp-server>} records) with which
14351 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
14354 @item @code{allow-large-adjustment?} (default: @code{#t})
14355 This determines whether @command{ntpd} is allowed to make an initial
14356 adjustment of more than 1,000 seconds.
14358 @item @code{ntp} (default: @code{ntp})
14359 The NTP package to use.
14363 @defvr {Scheme Variable} %ntp-servers
14364 List of host names used as the default NTP servers. These are servers of the
14365 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
14368 @deftp {Data Type} ntp-server
14369 The data type representing the configuration of a NTP server.
14372 @item @code{type} (default: @code{'server})
14373 The type of the NTP server, given as a symbol. One of @code{'pool},
14374 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
14376 @item @code{address}
14377 The address of the server, as a string.
14379 @item @code{options}
14380 NTPD options to use with that specific server, given as a list of option names
14381 and/or of option names and values tuples. The following example define a server
14382 to use with the options @option{iburst} and @option{prefer}, as well as
14383 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
14388 (address "some.ntp.server.org")
14389 (options `(iburst (version 3) (maxpoll 16) prefer))))
14395 @deffn {Scheme Procedure} openntpd-service-type
14396 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
14397 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
14398 clock synchronized with that of the given servers.
14402 openntpd-service-type
14403 (openntpd-configuration
14404 (listen-on '("127.0.0.1" "::1"))
14405 (sensor '("udcf0 correction 70000"))
14406 (constraint-from '("www.gnu.org"))
14407 (constraints-from '("https://www.google.com/"))
14408 (allow-large-adjustment? #t)))
14413 @defvr {Scheme Variable} %openntpd-servers
14414 This variable is a list of the server addresses defined in
14415 @code{%ntp-servers}.
14418 @deftp {Data Type} openntpd-configuration
14420 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
14421 The openntpd executable to use.
14422 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
14423 A list of local IP addresses or hostnames the ntpd daemon should listen on.
14424 @item @code{query-from} (default: @code{'()})
14425 A list of local IP address the ntpd daemon should use for outgoing queries.
14426 @item @code{sensor} (default: @code{'()})
14427 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
14428 will listen to each sensor that actually exists and ignore non-existent ones.
14429 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
14431 @item @code{server} (default: @code{'()})
14432 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
14433 @item @code{servers} (default: @code{%openntp-servers})
14434 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
14435 @item @code{constraint-from} (default: @code{'()})
14436 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
14437 This time information is not used for precision but acts as an authenticated
14438 constraint, thereby reducing the impact of unauthenticated NTP
14439 man-in-the-middle attacks.
14440 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
14442 @item @code{constraints-from} (default: @code{'()})
14443 As with constraint from, specify a list of URLs, IP addresses or hostnames of
14444 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
14445 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
14446 @item @code{allow-large-adjustment?} (default: @code{#f})
14447 Determines if @code{ntpd} is allowed to make an initial adjustment of more
14453 @deffn {Scheme variable} inetd-service-type
14454 This service runs the @command{inetd} (@pxref{inetd invocation,,,
14455 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
14456 connections on internet sockets, and lazily starts the specified server
14457 program when a connection is made on one of these sockets.
14459 The value of this service is an @code{inetd-configuration} object. The
14460 following example configures the @command{inetd} daemon to provide the
14461 built-in @command{echo} service, as well as an smtp service which
14462 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
14463 gateway @code{hostname}:
14468 (inetd-configuration
14472 (socket-type 'stream)
14479 (socket-type 'stream)
14483 (program (file-append openssh "/bin/ssh"))
14485 '("ssh" "-qT" "-i" "/path/to/ssh_key"
14486 "-W" "smtp-server:25" "user@@hostname")))))))
14489 See below for more details about @code{inetd-configuration}.
14492 @deftp {Data Type} inetd-configuration
14493 Data type representing the configuration of @command{inetd}.
14496 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
14497 The @command{inetd} executable to use.
14499 @item @code{entries} (default: @code{'()})
14500 A list of @command{inetd} service entries. Each entry should be created
14501 by the @code{inetd-entry} constructor.
14505 @deftp {Data Type} inetd-entry
14506 Data type representing an entry in the @command{inetd} configuration.
14507 Each entry corresponds to a socket where @command{inetd} will listen for
14511 @item @code{node} (default: @code{#f})
14512 Optional string, a comma-separated list of local addresses
14513 @command{inetd} should use when listening for this service.
14514 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
14515 description of all options.
14517 A string, the name must correspond to an entry in @code{/etc/services}.
14518 @item @code{socket-type}
14519 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
14521 @item @code{protocol}
14522 A string, must correspond to an entry in @code{/etc/protocols}.
14523 @item @code{wait?} (default: @code{#t})
14524 Whether @command{inetd} should wait for the server to exit before
14525 listening to new service requests.
14527 A string containing the user (and, optionally, group) name of the user
14528 as whom the server should run. The group name can be specified in a
14529 suffix, separated by a colon or period, i.e.@: @code{"user"},
14530 @code{"user:group"} or @code{"user.group"}.
14531 @item @code{program} (default: @code{"internal"})
14532 The server program which will serve the requests, or @code{"internal"}
14533 if @command{inetd} should use a built-in service.
14534 @item @code{arguments} (default: @code{'()})
14535 A list strings or file-like objects, which are the server program's
14536 arguments, starting with the zeroth argument, i.e.@: the name of the
14537 program itself. For @command{inetd}'s internal services, this entry
14538 must be @code{'()} or @code{'("internal")}.
14541 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
14542 detailed discussion of each configuration field.
14546 @defvr {Scheme Variable} tor-service-type
14547 This is the type for a service that runs the @uref{https://torproject.org,
14548 Tor} anonymous networking daemon. The service is configured using a
14549 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
14550 @code{tor} unprivileged user, which is a member of the @code{tor} group.
14554 @deftp {Data Type} tor-configuration
14556 @item @code{tor} (default: @code{tor})
14557 The package that provides the Tor daemon. This package is expected to provide
14558 the daemon at @file{bin/tor} relative to its output directory. The default
14559 package is the @uref{https://www.torproject.org, Tor Project's}
14562 @item @code{config-file} (default: @code{(plain-file "empty" "")})
14563 The configuration file to use. It will be appended to a default configuration
14564 file, and the final configuration file will be passed to @code{tor} via its
14565 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
14566 file-like objects}). See @code{man tor} for details on the configuration file
14569 @item @code{hidden-services} (default: @code{'()})
14570 The list of @code{<hidden-service>} records to use. For any hidden service
14571 you include in this list, appropriate configuration to enable the hidden
14572 service will be automatically added to the default configuration file. You
14573 may conveniently create @code{<hidden-service>} records using the
14574 @code{tor-hidden-service} procedure described below.
14576 @item @code{socks-socket-type} (default: @code{'tcp})
14577 The default socket type that Tor should use for its SOCKS socket. This must
14578 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
14579 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
14580 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
14581 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
14584 If you want to customize the SOCKS socket in more detail, leave
14585 @code{socks-socket-type} at its default value of @code{'tcp} and use
14586 @code{config-file} to override the default by providing your own
14587 @code{SocksPort} option.
14591 @cindex hidden service
14592 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
14593 Define a new Tor @dfn{hidden service} called @var{name} and implementing
14594 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
14597 '((22 "127.0.0.1:22")
14598 (80 "127.0.0.1:8080"))
14601 In this example, port 22 of the hidden service is mapped to local port 22, and
14602 port 80 is mapped to local port 8080.
14604 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
14605 the @file{hostname} file contains the @code{.onion} host name for the hidden
14608 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
14609 project's documentation} for more information.
14612 The @code{(gnu services rsync)} module provides the following services:
14614 You might want an rsync daemon if you have files that you want available
14615 so anyone (or just yourself) can download existing files or upload new
14618 @deffn {Scheme Variable} rsync-service-type
14619 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
14620 The value for this service type is a
14621 @command{rsync-configuration} record as in this example:
14624 (service rsync-service-type)
14627 See below for details about @code{rsync-configuration}.
14630 @deftp {Data Type} rsync-configuration
14631 Data type representing the configuration for @code{rsync-service}.
14634 @item @code{package} (default: @var{rsync})
14635 @code{rsync} package to use.
14637 @item @code{port-number} (default: @code{873})
14638 TCP port on which @command{rsync} listens for incoming connections. If port
14639 is less than @code{1024} @command{rsync} needs to be started as the
14640 @code{root} user and group.
14642 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
14643 Name of the file where @command{rsync} writes its PID.
14645 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
14646 Name of the file where @command{rsync} writes its lock file.
14648 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
14649 Name of the file where @command{rsync} writes its log file.
14651 @item @code{use-chroot?} (default: @var{#t})
14652 Whether to use chroot for @command{rsync} shared directory.
14654 @item @code{share-path} (default: @file{/srv/rsync})
14655 Location of the @command{rsync} shared directory.
14657 @item @code{share-comment} (default: @code{"Rsync share"})
14658 Comment of the @command{rsync} shared directory.
14660 @item @code{read-only?} (default: @var{#f})
14661 Read-write permissions to shared directory.
14663 @item @code{timeout} (default: @code{300})
14664 I/O timeout in seconds.
14666 @item @code{user} (default: @var{"root"})
14667 Owner of the @code{rsync} process.
14669 @item @code{group} (default: @var{"root"})
14670 Group of the @code{rsync} process.
14672 @item @code{uid} (default: @var{"rsyncd"})
14673 User name or user ID that file transfers to and from that module should take
14674 place as when the daemon was run as @code{root}.
14676 @item @code{gid} (default: @var{"rsyncd"})
14677 Group name or group ID that will be used when accessing the module.
14682 Furthermore, @code{(gnu services ssh)} provides the following services.
14686 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
14687 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
14688 [#:allow-empty-passwords? #f] [#:root-login? #f] @
14689 [#:syslog-output? #t] [#:x11-forwarding? #t] @
14690 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
14691 [#:public-key-authentication? #t] [#:initialize? #t]
14692 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
14693 @var{host-key} must designate a file containing the host key, and readable
14696 When @var{daemonic?} is true, @command{lshd} will detach from the
14697 controlling terminal and log its output to syslogd, unless one sets
14698 @var{syslog-output?} to false. Obviously, it also makes lsh-service
14699 depend on existence of syslogd service. When @var{pid-file?} is true,
14700 @command{lshd} writes its PID to the file called @var{pid-file}.
14702 When @var{initialize?} is true, automatically create the seed and host key
14703 upon service activation if they do not exist yet. This may take long and
14704 require interaction.
14706 When @var{initialize?} is false, it is up to the user to initialize the
14707 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
14708 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
14709 basics,,, lsh, LSH Manual}).
14711 When @var{interfaces} is empty, lshd listens for connections on all the
14712 network interfaces; otherwise, @var{interfaces} must be a list of host names
14715 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
14716 passwords, and @var{root-login?} specifies whether to accept log-ins as
14719 The other options should be self-descriptive.
14724 @deffn {Scheme Variable} openssh-service-type
14725 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
14726 shell daemon, @command{sshd}. Its value must be an
14727 @code{openssh-configuration} record as in this example:
14730 (service openssh-service-type
14731 (openssh-configuration
14732 (x11-forwarding? #t)
14733 (permit-root-login 'without-password)
14735 `(("alice" ,(local-file "alice.pub"))
14736 ("bob" ,(local-file "bob.pub"))))))
14739 See below for details about @code{openssh-configuration}.
14741 This service can be extended with extra authorized keys, as in this
14745 (service-extension openssh-service-type
14746 (const `(("charlie"
14747 ,(local-file "charlie.pub")))))
14751 @deftp {Data Type} openssh-configuration
14752 This is the configuration record for OpenSSH's @command{sshd}.
14755 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
14756 Name of the file where @command{sshd} writes its PID.
14758 @item @code{port-number} (default: @code{22})
14759 TCP port on which @command{sshd} listens for incoming connections.
14761 @item @code{permit-root-login} (default: @code{#f})
14762 This field determines whether and when to allow logins as root. If
14763 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
14764 If it's the symbol @code{'without-password}, then root logins are
14765 permitted but not with password-based authentication.
14767 @item @code{allow-empty-passwords?} (default: @code{#f})
14768 When true, users with empty passwords may log in. When false, they may
14771 @item @code{password-authentication?} (default: @code{#t})
14772 When true, users may log in with their password. When false, they have
14773 other authentication methods.
14775 @item @code{public-key-authentication?} (default: @code{#t})
14776 When true, users may log in using public key authentication. When
14777 false, users have to use other authentication method.
14779 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
14780 This is used only by protocol version 2.
14782 @item @code{x11-forwarding?} (default: @code{#f})
14783 When true, forwarding of X11 graphical client connections is
14784 enabled---in other words, @command{ssh} options @option{-X} and
14785 @option{-Y} will work.
14787 @item @code{allow-agent-forwarding?} (default: @code{#t})
14788 Whether to allow agent forwarding.
14790 @item @code{allow-tcp-forwarding?} (default: @code{#t})
14791 Whether to allow TCP forwarding.
14793 @item @code{gateway-ports?} (default: @code{#f})
14794 Whether to allow gateway ports.
14796 @item @code{challenge-response-authentication?} (default: @code{#f})
14797 Specifies whether challenge response authentication is allowed (e.g.@: via
14800 @item @code{use-pam?} (default: @code{#t})
14801 Enables the Pluggable Authentication Module interface. If set to
14802 @code{#t}, this will enable PAM authentication using
14803 @code{challenge-response-authentication?} and
14804 @code{password-authentication?}, in addition to PAM account and session
14805 module processing for all authentication types.
14807 Because PAM challenge response authentication usually serves an
14808 equivalent role to password authentication, you should disable either
14809 @code{challenge-response-authentication?} or
14810 @code{password-authentication?}.
14812 @item @code{print-last-log?} (default: @code{#t})
14813 Specifies whether @command{sshd} should print the date and time of the
14814 last user login when a user logs in interactively.
14816 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
14817 Configures external subsystems (e.g.@: file transfer daemon).
14819 This is a list of two-element lists, each of which containing the
14820 subsystem name and a command (with optional arguments) to execute upon
14823 The command @command{internal-sftp} implements an in-process SFTP
14824 server. Alternatively, one can specify the @command{sftp-server} command:
14826 (service openssh-service-type
14827 (openssh-configuration
14829 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
14832 @item @code{accepted-environment} (default: @code{'()})
14833 List of strings describing which environment variables may be exported.
14835 Each string gets on its own line. See the @code{AcceptEnv} option in
14836 @code{man sshd_config}.
14838 This example allows ssh-clients to export the @env{COLORTERM} variable.
14839 It is set by terminal emulators, which support colors. You can use it in
14840 your shell's resource file to enable colors for the prompt and commands
14841 if this variable is set.
14844 (service openssh-service-type
14845 (openssh-configuration
14846 (accepted-environment '("COLORTERM"))))
14849 @item @code{authorized-keys} (default: @code{'()})
14850 @cindex authorized keys, SSH
14851 @cindex SSH authorized keys
14852 This is the list of authorized keys. Each element of the list is a user
14853 name followed by one or more file-like objects that represent SSH public
14857 (openssh-configuration
14859 `(("rekado" ,(local-file "rekado.pub"))
14860 ("chris" ,(local-file "chris.pub"))
14861 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
14865 registers the specified public keys for user accounts @code{rekado},
14866 @code{chris}, and @code{root}.
14868 Additional authorized keys can be specified @i{via}
14869 @code{service-extension}.
14871 Note that this does @emph{not} interfere with the use of
14872 @file{~/.ssh/authorized_keys}.
14874 @item @code{log-level} (default: @code{'info})
14875 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
14876 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
14877 page for @file{sshd_config} for the full list of level names.
14879 @item @code{extra-content} (default: @code{""})
14880 This field can be used to append arbitrary text to the configuration file. It
14881 is especially useful for elaborate configurations that cannot be expressed
14882 otherwise. This configuration, for example, would generally disable root
14883 logins, but permit them from one specific IP address:
14886 (openssh-configuration
14888 Match Address 192.168.0.1
14889 PermitRootLogin yes"))
14895 @deffn {Scheme Procedure} dropbear-service [@var{config}]
14896 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
14897 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
14900 For example, to specify a Dropbear service listening on port 1234, add
14901 this call to the operating system's @code{services} field:
14904 (dropbear-service (dropbear-configuration
14905 (port-number 1234)))
14909 @deftp {Data Type} dropbear-configuration
14910 This data type represents the configuration of a Dropbear SSH daemon.
14913 @item @code{dropbear} (default: @var{dropbear})
14914 The Dropbear package to use.
14916 @item @code{port-number} (default: 22)
14917 The TCP port where the daemon waits for incoming connections.
14919 @item @code{syslog-output?} (default: @code{#t})
14920 Whether to enable syslog output.
14922 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
14923 File name of the daemon's PID file.
14925 @item @code{root-login?} (default: @code{#f})
14926 Whether to allow @code{root} logins.
14928 @item @code{allow-empty-passwords?} (default: @code{#f})
14929 Whether to allow empty passwords.
14931 @item @code{password-authentication?} (default: @code{#t})
14932 Whether to enable password-based authentication.
14937 @deffn {Scheme Variable} autossh-service-type
14938 This is the type for the @uref{https://www.harding.motd.ca/autossh,
14939 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
14940 restarting it as necessary should it die or stop passing traffic.
14941 AutoSSH can be run manually from the command-line by passing arguments
14942 to the binary @command{autossh} from the package @code{autossh}, but it
14943 can also be run as a Guix service. This latter use case is documented
14946 AutoSSH can be used to forward local traffic to a remote machine using
14947 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
14950 For example, to specify a service running autossh as the user
14951 @code{pino} and forwarding all local connections to port @code{8081} to
14952 @code{remote:8081} using an SSH tunnel, add this call to the operating
14953 system's @code{services} field:
14956 (service autossh-service-type
14957 (autossh-configuration
14959 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
14963 @deftp {Data Type} autossh-configuration
14964 This data type represents the configuration of an AutoSSH service.
14968 @item @code{user} (default @code{"autossh"})
14969 The user as which the AutoSSH service is to be run.
14970 This assumes that the specified user exists.
14972 @item @code{poll} (default @code{600})
14973 Specifies the connection poll time in seconds.
14975 @item @code{first-poll} (default @code{#f})
14976 Specifies how many seconds AutoSSH waits before the first connection
14977 test. After this first test, polling is resumed at the pace defined in
14978 @code{poll}. When set to @code{#f}, the first poll is not treated
14979 specially and will also use the connection poll specified in
14982 @item @code{gate-time} (default @code{30})
14983 Specifies how many seconds an SSH connection must be active before it is
14984 considered successful.
14986 @item @code{log-level} (default @code{1})
14987 The log level, corresponding to the levels used by syslog---so @code{0}
14988 is the most silent while @code{7} is the chattiest.
14990 @item @code{max-start} (default @code{#f})
14991 The maximum number of times SSH may be (re)started before AutoSSH exits.
14992 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
14994 @item @code{message} (default @code{""})
14995 The message to append to the echo message sent when testing connections.
14997 @item @code{port} (default @code{"0"})
14998 The ports used for monitoring the connection. When set to @code{"0"},
14999 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
15000 a positive integer, ports @var{n} and @var{n}+1 are used for
15001 monitoring the connection, such that port @var{n} is the base
15002 monitoring port and @code{n+1} is the echo port. When set to
15003 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
15004 integers, the ports @var{n} and @var{n}+1 are used for monitoring the
15005 connection, such that port @var{n} is the base monitoring port and
15006 @var{m} is the echo port.
15008 @item @code{ssh-options} (default @code{'()})
15009 The list of command-line arguments to pass to @command{ssh} when it is
15010 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
15011 may cause undefined behaviour.
15016 @defvr {Scheme Variable} %facebook-host-aliases
15017 This variable contains a string for use in @file{/etc/hosts}
15018 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
15019 line contains a entry that maps a known server name of the Facebook
15020 on-line service---e.g., @code{www.facebook.com}---to the local
15021 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
15023 This variable is typically used in the @code{hosts-file} field of an
15024 @code{operating-system} declaration (@pxref{operating-system Reference,
15025 @file{/etc/hosts}}):
15028 (use-modules (gnu) (guix))
15031 (host-name "mymachine")
15034 ;; Create a /etc/hosts file with aliases for "localhost"
15035 ;; and "mymachine", as well as for Facebook servers.
15036 (plain-file "hosts"
15037 (string-append (local-host-aliases host-name)
15038 %facebook-host-aliases))))
15041 This mechanism can prevent programs running locally, such as Web
15042 browsers, from accessing Facebook.
15045 The @code{(gnu services avahi)} provides the following definition.
15047 @defvr {Scheme Variable} avahi-service-type
15048 This is the service that runs @command{avahi-daemon}, a system-wide
15049 mDNS/DNS-SD responder that allows for service discovery and
15050 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
15051 Its value must be a @code{zero-configuration} record---see below.
15053 This service extends the name service cache daemon (nscd) so that it can
15054 resolve @code{.local} host names using
15055 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
15056 Service Switch}, for information on host name resolution.
15058 Additionally, add the @var{avahi} package to the system profile so that
15059 commands such as @command{avahi-browse} are directly usable.
15062 @deftp {Data Type} avahi-configuration
15063 Data type representation the configuration for Avahi.
15067 @item @code{host-name} (default: @code{#f})
15068 If different from @code{#f}, use that as the host name to
15069 publish for this machine; otherwise, use the machine's actual host name.
15071 @item @code{publish?} (default: @code{#t})
15072 When true, allow host names and services to be published (broadcast) over the
15075 @item @code{publish-workstation?} (default: @code{#t})
15076 When true, @command{avahi-daemon} publishes the machine's host name and IP
15077 address via mDNS on the local network. To view the host names published on
15078 your local network, you can run:
15081 avahi-browse _workstation._tcp
15084 @item @code{wide-area?} (default: @code{#f})
15085 When true, DNS-SD over unicast DNS is enabled.
15087 @item @code{ipv4?} (default: @code{#t})
15088 @itemx @code{ipv6?} (default: @code{#t})
15089 These fields determine whether to use IPv4/IPv6 sockets.
15091 @item @code{domains-to-browse} (default: @code{'()})
15092 This is a list of domains to browse.
15096 @deffn {Scheme Variable} openvswitch-service-type
15097 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
15098 service, whose value should be an @code{openvswitch-configuration}
15102 @deftp {Data Type} openvswitch-configuration
15103 Data type representing the configuration of Open vSwitch, a multilayer
15104 virtual switch which is designed to enable massive network automation
15105 through programmatic extension.
15108 @item @code{package} (default: @var{openvswitch})
15109 Package object of the Open vSwitch.
15114 @defvr {Scheme Variable} pagekite-service-type
15115 This is the service type for the @uref{https://pagekite.net, PageKite} service,
15116 a tunneling solution for making localhost servers publicly visible, even from
15117 behind restrictive firewalls or NAT without forwarded ports. The value for
15118 this service type is a @code{pagekite-configuration} record.
15120 Here's an example exposing the local HTTP and SSH daemons:
15123 (service pagekite-service-type
15124 (pagekite-configuration
15125 (kites '("http:@@kitename:localhost:80:@@kitesecret"
15126 "raw/22:@@kitename:localhost:22:@@kitesecret"))
15127 (extra-file "/etc/pagekite.rc")))
15131 @deftp {Data Type} pagekite-configuration
15132 Data type representing the configuration of PageKite.
15135 @item @code{package} (default: @var{pagekite})
15136 Package object of PageKite.
15138 @item @code{kitename} (default: @code{#f})
15139 PageKite name for authenticating to the frontend server.
15141 @item @code{kitesecret} (default: @code{#f})
15142 Shared secret for authenticating to the frontend server. You should probably
15143 put this inside @code{extra-file} instead.
15145 @item @code{frontend} (default: @code{#f})
15146 Connect to the named PageKite frontend server instead of the
15147 @uref{https://pagekite.net,,pagekite.net} service.
15149 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
15150 List of service kites to use. Exposes HTTP on port 80 by default. The format
15151 is @code{proto:kitename:host:port:secret}.
15153 @item @code{extra-file} (default: @code{#f})
15154 Extra configuration file to read, which you are expected to create manually.
15155 Use this to add additional options and manage shared secrets out-of-band.
15161 @subsection X Window
15164 @cindex X Window System
15165 @cindex login manager
15166 Support for the X Window graphical display system---specifically
15167 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
15168 there is no @code{xorg-service} procedure. Instead, the X server is
15169 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
15172 @cindex GNOME, login manager
15173 GDM of course allows users to log in into window managers and desktop
15174 environments other than GNOME; for those using GNOME, GDM is required for
15175 features such as automatic screen locking.
15177 @cindex window manager
15178 To use X11, you must install at least one @dfn{window manager}---for
15179 example the @code{windowmaker} or @code{openbox} packages---preferably
15180 by adding it to the @code{packages} field of your operating system
15181 definition (@pxref{operating-system Reference, system-wide packages}).
15183 @defvr {Scheme Variable} gdm-service-type
15184 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
15185 Desktop Manager} (GDM), a program that manages graphical display servers and
15186 handles graphical user logins. Its value must be a @code{gdm-configuration}
15189 @cindex session types (X11)
15190 @cindex X11 session types
15191 GDM looks for @dfn{session types} described by the @file{.desktop} files in
15192 @file{/run/current-system/profile/share/xsessions} and allows users to choose
15193 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
15194 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
15195 set of packages automatically makes them available at the log-in screen.
15197 In addition, @file{~/.xsession} files are honored. When available,
15198 @file{~/.xsession} must be an executable that starts a window manager
15199 and/or other X clients.
15202 @deftp {Data Type} gdm-configuration
15204 @item @code{auto-login?} (default: @code{#f})
15205 @itemx @code{default-user} (default: @code{#f})
15206 When @code{auto-login?} is false, GDM presents a log-in screen.
15208 When @code{auto-login?} is true, GDM logs in directly as
15209 @code{default-user}.
15211 @item @code{debug?} (default: @code{#f})
15212 When true, GDM writes debug messages to its log.
15214 @item @code{gnome-shell-assets} (default: ...)
15215 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
15217 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
15218 Configuration of the Xorg graphical server.
15220 @item @code{xsession} (default: @code{(xinitrc)})
15221 Script to run before starting a X session.
15223 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
15224 File name of the @code{dbus-daemon} executable.
15226 @item @code{gdm} (default: @code{gdm})
15227 The GDM package to use.
15231 @defvr {Scheme Variable} slim-service-type
15232 This is the type for the SLiM graphical login manager for X11.
15234 Like GDM, SLiM looks for session types described by @file{.desktop} files and
15235 allows users to choose a session from the log-in screen using @kbd{F1}. It
15236 also honors @file{~/.xsession} files.
15238 Unlike GDM, SLiM does not spawn the user session on a different VT after
15239 logging in, which means that you can only start one graphical session. If you
15240 want to be able to run multiple graphical sessions at the same time you have
15241 to add multiple SLiM services to your system services. The following example
15242 shows how to replace the default GDM service with two SLiM services on tty7
15246 (use-modules (gnu services)
15247 (gnu services desktop)
15248 (gnu services xorg)
15249 (srfi srfi-1)) ;for 'remove'
15253 (services (cons* (service slim-service-type (slim-configuration
15256 (service slim-service-type (slim-configuration
15259 (remove (lambda (service)
15260 (eq? (service-kind service) gdm-service-type))
15261 %desktop-services))))
15266 @deftp {Data Type} slim-configuration
15267 Data type representing the configuration of @code{slim-service-type}.
15270 @item @code{allow-empty-passwords?} (default: @code{#t})
15271 Whether to allow logins with empty passwords.
15273 @item @code{auto-login?} (default: @code{#f})
15274 @itemx @code{default-user} (default: @code{""})
15275 When @code{auto-login?} is false, SLiM presents a log-in screen.
15277 When @code{auto-login?} is true, SLiM logs in directly as
15278 @code{default-user}.
15280 @item @code{theme} (default: @code{%default-slim-theme})
15281 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
15282 The graphical theme to use and its name.
15284 @item @code{auto-login-session} (default: @code{#f})
15285 If true, this must be the name of the executable to start as the default
15286 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
15288 If false, a session described by one of the available @file{.desktop}
15289 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
15293 You must install at least one window manager in the system profile or in
15294 your user profile. Failing to do that, if @code{auto-login-session} is
15295 false, you will be unable to log in.
15298 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
15299 Configuration of the Xorg graphical server.
15301 @item @code{display} (default @code{":0"})
15302 The display on which to start the Xorg graphical server.
15304 @item @code{vt} (default @code{"vt7"})
15305 The VT on which to start the Xorg graphical server.
15307 @item @code{xauth} (default: @code{xauth})
15308 The XAuth package to use.
15310 @item @code{shepherd} (default: @code{shepherd})
15311 The Shepherd package used when invoking @command{halt} and
15314 @item @code{sessreg} (default: @code{sessreg})
15315 The sessreg package used in order to register the session.
15317 @item @code{slim} (default: @code{slim})
15318 The SLiM package to use.
15322 @defvr {Scheme Variable} %default-theme
15323 @defvrx {Scheme Variable} %default-theme-name
15324 The default SLiM theme and its name.
15328 @deftp {Data Type} sddm-configuration
15329 This is the data type representing the SDDM service configuration.
15332 @item @code{display-server} (default: "x11")
15333 Select display server to use for the greeter. Valid values are
15334 @samp{"x11"} or @samp{"wayland"}.
15336 @item @code{numlock} (default: "on")
15337 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
15339 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
15340 Command to run when halting.
15342 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
15343 Command to run when rebooting.
15345 @item @code{theme} (default "maldives")
15346 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
15347 @samp{"maldives"} or @samp{"maya"}.
15349 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
15350 Directory to look for themes.
15352 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
15353 Directory to look for faces.
15355 @item @code{default-path} (default "/run/current-system/profile/bin")
15356 Default PATH to use.
15358 @item @code{minimum-uid} (default: 1000)
15359 Minimum UID displayed in SDDM and allowed for log-in.
15361 @item @code{maximum-uid} (default: 2000)
15362 Maximum UID to display in SDDM.
15364 @item @code{remember-last-user?} (default #t)
15365 Remember last user.
15367 @item @code{remember-last-session?} (default #t)
15368 Remember last session.
15370 @item @code{hide-users} (default "")
15371 Usernames to hide from SDDM greeter.
15373 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
15374 Users with shells listed will be hidden from the SDDM greeter.
15376 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
15377 Script to run before starting a wayland session.
15379 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
15380 Directory to look for desktop files starting wayland sessions.
15382 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
15383 Configuration of the Xorg graphical server.
15385 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
15388 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
15391 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
15392 Script to run after starting xorg-server.
15394 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
15395 Script to run before stopping xorg-server.
15397 @item @code{xsession-command} (default: @code{xinitrc})
15398 Script to run before starting a X session.
15400 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
15401 Directory to look for desktop files starting X sessions.
15403 @item @code{minimum-vt} (default: 7)
15406 @item @code{auto-login-user} (default "")
15407 User to use for auto-login.
15409 @item @code{auto-login-session} (default "")
15410 Desktop file to use for auto-login.
15412 @item @code{relogin?} (default #f)
15413 Relogin after logout.
15418 @cindex login manager
15420 @defvr {Scheme Variable} sddm-service-type
15421 This is the type of the service to run the
15422 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
15423 must be a @code{sddm-configuration} record (see below).
15425 Here's an example use:
15428 (service sddm-service-type
15429 (sddm-configuration
15430 (auto-login-user "alice")
15431 (auto-login-session "xfce.desktop")))
15435 @deftp {Data Type} sddm-configuration
15436 This data type represents the configuration of the SDDM login manager.
15437 The available fields are:
15440 @item @code{sddm} (default: @code{sddm})
15441 The SDDM package to use.
15443 @item @code{display-server} (default: @code{"x11"})
15444 This must be either @code{"x11"} or @code{"wayland"}.
15446 @c FIXME: Add more fields.
15448 @item @code{auto-login-user} (default: @code{""})
15449 If non-empty, this is the user account under which to log in
15452 @item @code{auto-login-session} (default: @code{""})
15453 If non-empty, this is the @file{.desktop} file name to use as the
15454 auto-login session.
15458 @cindex Xorg, configuration
15459 @deftp {Data Type} xorg-configuration
15460 This data type represents the configuration of the Xorg graphical display
15461 server. Note that there is no Xorg service; instead, the X server is started
15462 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
15463 of these display managers aggregates an @code{xorg-configuration} record.
15466 @item @code{modules} (default: @code{%default-xorg-modules})
15467 This is a list of @dfn{module packages} loaded by the Xorg
15468 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
15470 @item @code{fonts} (default: @code{%default-xorg-fonts})
15471 This is a list of font directories to add to the server's @dfn{font path}.
15473 @item @code{drivers} (default: @code{'()})
15474 This must be either the empty list, in which case Xorg chooses a graphics
15475 driver automatically, or a list of driver names that will be tried in this
15476 order---e.g., @code{("modesetting" "vesa")}.
15478 @item @code{resolutions} (default: @code{'()})
15479 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
15480 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
15483 @cindex keyboard layout, for Xorg
15484 @cindex keymap, for Xorg
15485 @item @code{keyboard-layout} (default: @code{#f})
15486 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
15487 English (``qwerty'') for a 105-key PC keyboard.
15489 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
15490 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
15491 information on how to specify the keyboard layout.
15493 @item @code{extra-config} (default: @code{'()})
15494 This is a list of strings or objects appended to the configuration file. It
15495 is used to pass extra text to be added verbatim to the configuration file.
15497 @item @code{server} (default: @code{xorg-server})
15498 This is the package providing the Xorg server.
15500 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
15501 This is the list of command-line arguments to pass to the X server. The
15502 default is @code{-nolisten tcp}.
15506 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
15507 [@var{login-manager-service-type}]
15508 Tell the log-in manager (of type @var{login-manager-service-type}) to use
15509 @var{config}, an @code{<xorg-configuration>} record.
15511 Since the Xorg configuration is embedded in the log-in manager's
15512 configuration---e.g., @code{gdm-configuration}---this procedure provides a
15513 shorthand to set the Xorg configuration.
15516 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
15517 Return a @code{startx} script in which the modules, fonts, etc. specified
15518 in @var{config}, are available. The result should be used in place of
15521 Usually the X server is started by a login manager.
15525 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
15526 Add @var{package}, a package for a screen locker or screen saver whose
15527 command is @var{program}, to the set of setuid programs and add a PAM entry
15528 for it. For example:
15531 (screen-locker-service xlockmore "xlock")
15534 makes the good ol' XlockMore usable.
15538 @node Printing Services
15539 @subsection Printing Services
15541 @cindex printer support with CUPS
15542 The @code{(gnu services cups)} module provides a Guix service definition
15543 for the CUPS printing service. To add printer support to a Guix
15544 system, add a @code{cups-service} to the operating system definition:
15546 @deffn {Scheme Variable} cups-service-type
15547 The service type for the CUPS print server. Its value should be a valid
15548 CUPS configuration (see below). To use the default settings, simply
15551 (service cups-service-type)
15555 The CUPS configuration controls the basic things about your CUPS
15556 installation: what interfaces it listens on, what to do if a print job
15557 fails, how much logging to do, and so on. To actually add a printer,
15558 you have to visit the @url{http://localhost:631} URL, or use a tool such
15559 as GNOME's printer configuration services. By default, configuring a
15560 CUPS service will generate a self-signed certificate if needed, for
15561 secure connections to the print server.
15563 Suppose you want to enable the Web interface of CUPS and also add
15564 support for Epson printers @i{via} the @code{escpr} package and for HP
15565 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
15566 like this (you need to use the @code{(gnu packages cups)} module):
15569 (service cups-service-type
15570 (cups-configuration
15571 (web-interface? #t)
15573 (list cups-filters escpr hplip-minimal))))
15576 Note: If you wish to use the Qt5 based GUI which comes with the hplip
15577 package then it is suggested that you install the @code{hplip} package,
15578 either in your OS configuration file or as your user.
15580 The available configuration parameters follow. Each parameter
15581 definition is preceded by its type; for example, @samp{string-list foo}
15582 indicates that the @code{foo} parameter should be specified as a list of
15583 strings. There is also a way to specify the configuration as a string,
15584 if you have an old @code{cupsd.conf} file that you want to port over
15585 from some other system; see the end for more details.
15587 @c The following documentation was initially generated by
15588 @c (generate-documentation) in (gnu services cups). Manually maintained
15589 @c documentation is better, so we shouldn't hesitate to edit below as
15590 @c needed. However if the change you want to make to this documentation
15591 @c can be done in an automated way, it's probably easier to change
15592 @c (generate-documentation) than to make it below and have to deal with
15593 @c the churn as CUPS updates.
15596 Available @code{cups-configuration} fields are:
15598 @deftypevr {@code{cups-configuration} parameter} package cups
15602 @deftypevr {@code{cups-configuration} parameter} package-list extensions
15603 Drivers and other extensions to the CUPS package.
15606 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
15607 Configuration of where to write logs, what directories to use for print
15608 spools, and related privileged configuration parameters.
15610 Available @code{files-configuration} fields are:
15612 @deftypevr {@code{files-configuration} parameter} log-location access-log
15613 Defines the access log filename. Specifying a blank filename disables
15614 access log generation. The value @code{stderr} causes log entries to be
15615 sent to the standard error file when the scheduler is running in the
15616 foreground, or to the system log daemon when run in the background. The
15617 value @code{syslog} causes log entries to be sent to the system log
15618 daemon. The server name may be included in filenames using the string
15619 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
15621 Defaults to @samp{"/var/log/cups/access_log"}.
15624 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
15625 Where CUPS should cache data.
15627 Defaults to @samp{"/var/cache/cups"}.
15630 @deftypevr {@code{files-configuration} parameter} string config-file-perm
15631 Specifies the permissions for all configuration files that the scheduler
15634 Note that the permissions for the printers.conf file are currently
15635 masked to only allow access from the scheduler user (typically root).
15636 This is done because printer device URIs sometimes contain sensitive
15637 authentication information that should not be generally known on the
15638 system. There is no way to disable this security feature.
15640 Defaults to @samp{"0640"}.
15643 @deftypevr {@code{files-configuration} parameter} log-location error-log
15644 Defines the error log filename. Specifying a blank filename disables
15645 error log generation. The value @code{stderr} causes log entries to be
15646 sent to the standard error file when the scheduler is running in the
15647 foreground, or to the system log daemon when run in the background. The
15648 value @code{syslog} causes log entries to be sent to the system log
15649 daemon. The server name may be included in filenames using the string
15650 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
15652 Defaults to @samp{"/var/log/cups/error_log"}.
15655 @deftypevr {@code{files-configuration} parameter} string fatal-errors
15656 Specifies which errors are fatal, causing the scheduler to exit. The
15661 No errors are fatal.
15664 All of the errors below are fatal.
15667 Browsing initialization errors are fatal, for example failed connections
15668 to the DNS-SD daemon.
15671 Configuration file syntax errors are fatal.
15674 Listen or Port errors are fatal, except for IPv6 failures on the
15675 loopback or @code{any} addresses.
15678 Log file creation or write errors are fatal.
15681 Bad startup file permissions are fatal, for example shared TLS
15682 certificate and key files with world-read permissions.
15685 Defaults to @samp{"all -browse"}.
15688 @deftypevr {@code{files-configuration} parameter} boolean file-device?
15689 Specifies whether the file pseudo-device can be used for new printer
15690 queues. The URI @uref{file:///dev/null} is always allowed.
15692 Defaults to @samp{#f}.
15695 @deftypevr {@code{files-configuration} parameter} string group
15696 Specifies the group name or ID that will be used when executing external
15699 Defaults to @samp{"lp"}.
15702 @deftypevr {@code{files-configuration} parameter} string log-file-perm
15703 Specifies the permissions for all log files that the scheduler writes.
15705 Defaults to @samp{"0644"}.
15708 @deftypevr {@code{files-configuration} parameter} log-location page-log
15709 Defines the page log filename. Specifying a blank filename disables
15710 page log generation. The value @code{stderr} causes log entries to be
15711 sent to the standard error file when the scheduler is running in the
15712 foreground, or to the system log daemon when run in the background. The
15713 value @code{syslog} causes log entries to be sent to the system log
15714 daemon. The server name may be included in filenames using the string
15715 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
15717 Defaults to @samp{"/var/log/cups/page_log"}.
15720 @deftypevr {@code{files-configuration} parameter} string remote-root
15721 Specifies the username that is associated with unauthenticated accesses
15722 by clients claiming to be the root user. The default is @code{remroot}.
15724 Defaults to @samp{"remroot"}.
15727 @deftypevr {@code{files-configuration} parameter} file-name request-root
15728 Specifies the directory that contains print jobs and other HTTP request
15731 Defaults to @samp{"/var/spool/cups"}.
15734 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
15735 Specifies the level of security sandboxing that is applied to print
15736 filters, backends, and other child processes of the scheduler; either
15737 @code{relaxed} or @code{strict}. This directive is currently only
15738 used/supported on macOS.
15740 Defaults to @samp{strict}.
15743 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
15744 Specifies the location of TLS certificates and private keys. CUPS will
15745 look for public and private keys in this directory: @file{.crt} files
15746 for PEM-encoded certificates and corresponding @file{.key} files for
15747 PEM-encoded private keys.
15749 Defaults to @samp{"/etc/cups/ssl"}.
15752 @deftypevr {@code{files-configuration} parameter} file-name server-root
15753 Specifies the directory containing the server configuration files.
15755 Defaults to @samp{"/etc/cups"}.
15758 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
15759 Specifies whether the scheduler calls fsync(2) after writing
15760 configuration or state files.
15762 Defaults to @samp{#f}.
15765 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
15766 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
15769 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
15770 Specifies the directory where temporary files are stored.
15772 Defaults to @samp{"/var/spool/cups/tmp"}.
15775 @deftypevr {@code{files-configuration} parameter} string user
15776 Specifies the user name or ID that is used when running external
15779 Defaults to @samp{"lp"}.
15782 @deftypevr {@code{files-configuration} parameter} string set-env
15783 Set the specified environment variable to be passed to child processes.
15785 Defaults to @samp{"variable value"}.
15789 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
15790 Specifies the logging level for the AccessLog file. The @code{config}
15791 level logs when printers and classes are added, deleted, or modified and
15792 when configuration files are accessed or updated. The @code{actions}
15793 level logs when print jobs are submitted, held, released, modified, or
15794 canceled, and any of the conditions for @code{config}. The @code{all}
15795 level logs all requests.
15797 Defaults to @samp{actions}.
15800 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
15801 Specifies whether to purge job history data automatically when it is no
15802 longer required for quotas.
15804 Defaults to @samp{#f}.
15807 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
15808 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
15809 For example, @samp{"_cups" "_print"} will tell network clients that both
15810 CUPS sharing and IPP Everywhere are supported.
15812 Defaults to @samp{"_cups"}.
15815 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
15816 Specifies which protocols to use for local printer sharing.
15818 Defaults to @samp{dnssd}.
15821 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
15822 Specifies whether the CUPS web interface is advertised.
15824 Defaults to @samp{#f}.
15827 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
15828 Specifies whether shared printers are advertised.
15830 Defaults to @samp{#f}.
15833 @deftypevr {@code{cups-configuration} parameter} string classification
15834 Specifies the security classification of the server. Any valid banner
15835 name can be used, including @samp{"classified"}, @samp{"confidential"},
15836 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
15837 banner can be omitted to disable secure printing functions.
15839 Defaults to @samp{""}.
15842 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
15843 Specifies whether users may override the classification (cover page) of
15844 individual print jobs using the @code{job-sheets} option.
15846 Defaults to @samp{#f}.
15849 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
15850 Specifies the default type of authentication to use.
15852 Defaults to @samp{Basic}.
15855 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
15856 Specifies whether encryption will be used for authenticated requests.
15858 Defaults to @samp{Required}.
15861 @deftypevr {@code{cups-configuration} parameter} string default-language
15862 Specifies the default language to use for text and web content.
15864 Defaults to @samp{"en"}.
15867 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
15868 Specifies the default paper size for new print queues. @samp{"Auto"}
15869 uses a locale-specific default, while @samp{"None"} specifies there is
15870 no default paper size. Specific size names are typically
15871 @samp{"Letter"} or @samp{"A4"}.
15873 Defaults to @samp{"Auto"}.
15876 @deftypevr {@code{cups-configuration} parameter} string default-policy
15877 Specifies the default access policy to use.
15879 Defaults to @samp{"default"}.
15882 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
15883 Specifies whether local printers are shared by default.
15885 Defaults to @samp{#t}.
15888 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
15889 Specifies the delay for updating of configuration and state files, in
15890 seconds. A value of 0 causes the update to happen as soon as possible,
15891 typically within a few milliseconds.
15893 Defaults to @samp{30}.
15896 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
15897 Specifies what to do when an error occurs. Possible values are
15898 @code{abort-job}, which will discard the failed print job;
15899 @code{retry-job}, which will retry the job at a later time;
15900 @code{retry-current-job}, which retries the failed job immediately; and
15901 @code{stop-printer}, which stops the printer.
15903 Defaults to @samp{stop-printer}.
15906 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
15907 Specifies the maximum cost of filters that are run concurrently, which
15908 can be used to minimize disk, memory, and CPU resource problems. A
15909 limit of 0 disables filter limiting. An average print to a
15910 non-PostScript printer needs a filter limit of about 200. A PostScript
15911 printer needs about half that (100). Setting the limit below these
15912 thresholds will effectively limit the scheduler to printing a single job
15915 Defaults to @samp{0}.
15918 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
15919 Specifies the scheduling priority of filters that are run to print a
15920 job. The nice value ranges from 0, the highest priority, to 19, the
15923 Defaults to @samp{0}.
15926 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
15927 Specifies whether to do reverse lookups on connecting clients. The
15928 @code{double} setting causes @code{cupsd} to verify that the hostname
15929 resolved from the address matches one of the addresses returned for that
15930 hostname. Double lookups also prevent clients with unregistered
15931 addresses from connecting to your server. Only set this option to
15932 @code{#t} or @code{double} if absolutely required.
15934 Defaults to @samp{#f}.
15937 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
15938 Specifies the number of seconds to wait before killing the filters and
15939 backend associated with a canceled or held job.
15941 Defaults to @samp{30}.
15944 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
15945 Specifies the interval between retries of jobs in seconds. This is
15946 typically used for fax queues but can also be used with normal print
15947 queues whose error policy is @code{retry-job} or
15948 @code{retry-current-job}.
15950 Defaults to @samp{30}.
15953 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
15954 Specifies the number of retries that are done for jobs. This is
15955 typically used for fax queues but can also be used with normal print
15956 queues whose error policy is @code{retry-job} or
15957 @code{retry-current-job}.
15959 Defaults to @samp{5}.
15962 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
15963 Specifies whether to support HTTP keep-alive connections.
15965 Defaults to @samp{#t}.
15968 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
15969 Specifies how long an idle client connection remains open, in seconds.
15971 Defaults to @samp{30}.
15974 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
15975 Specifies the maximum size of print files, IPP requests, and HTML form
15976 data. A limit of 0 disables the limit check.
15978 Defaults to @samp{0}.
15981 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
15982 Listens on the specified interfaces for connections. Valid values are
15983 of the form @var{address}:@var{port}, where @var{address} is either an
15984 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
15985 indicate all addresses. Values can also be file names of local UNIX
15986 domain sockets. The Listen directive is similar to the Port directive
15987 but allows you to restrict access to specific interfaces or networks.
15990 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
15991 Specifies the number of pending connections that will be allowed. This
15992 normally only affects very busy servers that have reached the MaxClients
15993 limit, but can also be triggered by large numbers of simultaneous
15994 connections. When the limit is reached, the operating system will
15995 refuse additional connections until the scheduler can accept the pending
15998 Defaults to @samp{128}.
16001 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
16002 Specifies a set of additional access controls.
16004 Available @code{location-access-controls} fields are:
16006 @deftypevr {@code{location-access-controls} parameter} file-name path
16007 Specifies the URI path to which the access control applies.
16010 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
16011 Access controls for all access to this path, in the same format as the
16012 @code{access-controls} of @code{operation-access-control}.
16014 Defaults to @samp{()}.
16017 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
16018 Access controls for method-specific access to this path.
16020 Defaults to @samp{()}.
16022 Available @code{method-access-controls} fields are:
16024 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
16025 If @code{#t}, apply access controls to all methods except the listed
16026 methods. Otherwise apply to only the listed methods.
16028 Defaults to @samp{#f}.
16031 @deftypevr {@code{method-access-controls} parameter} method-list methods
16032 Methods to which this access control applies.
16034 Defaults to @samp{()}.
16037 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
16038 Access control directives, as a list of strings. Each string should be
16039 one directive, such as @samp{"Order allow,deny"}.
16041 Defaults to @samp{()}.
16046 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
16047 Specifies the number of debugging messages that are retained for logging
16048 if an error occurs in a print job. Debug messages are logged regardless
16049 of the LogLevel setting.
16051 Defaults to @samp{100}.
16054 @deftypevr {@code{cups-configuration} parameter} log-level log-level
16055 Specifies the level of logging for the ErrorLog file. The value
16056 @code{none} stops all logging while @code{debug2} logs everything.
16058 Defaults to @samp{info}.
16061 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
16062 Specifies the format of the date and time in the log files. The value
16063 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
16065 Defaults to @samp{standard}.
16068 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
16069 Specifies the maximum number of simultaneous clients that are allowed by
16072 Defaults to @samp{100}.
16075 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
16076 Specifies the maximum number of simultaneous clients that are allowed
16077 from a single address.
16079 Defaults to @samp{100}.
16082 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
16083 Specifies the maximum number of copies that a user can print of each
16086 Defaults to @samp{9999}.
16089 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
16090 Specifies the maximum time a job may remain in the @code{indefinite}
16091 hold state before it is canceled. A value of 0 disables cancellation of
16094 Defaults to @samp{0}.
16097 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
16098 Specifies the maximum number of simultaneous jobs that are allowed. Set
16099 to 0 to allow an unlimited number of jobs.
16101 Defaults to @samp{500}.
16104 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
16105 Specifies the maximum number of simultaneous jobs that are allowed per
16106 printer. A value of 0 allows up to MaxJobs jobs per printer.
16108 Defaults to @samp{0}.
16111 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
16112 Specifies the maximum number of simultaneous jobs that are allowed per
16113 user. A value of 0 allows up to MaxJobs jobs per user.
16115 Defaults to @samp{0}.
16118 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
16119 Specifies the maximum time a job may take to print before it is
16120 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
16122 Defaults to @samp{10800}.
16125 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
16126 Specifies the maximum size of the log files before they are rotated, in
16127 bytes. The value 0 disables log rotation.
16129 Defaults to @samp{1048576}.
16132 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
16133 Specifies the maximum amount of time to allow between files in a
16134 multiple file print job, in seconds.
16136 Defaults to @samp{300}.
16139 @deftypevr {@code{cups-configuration} parameter} string page-log-format
16140 Specifies the format of PageLog lines. Sequences beginning with percent
16141 (@samp{%}) characters are replaced with the corresponding information,
16142 while all other characters are copied literally. The following percent
16143 sequences are recognized:
16147 insert a single percent character
16150 insert the value of the specified IPP attribute
16153 insert the number of copies for the current page
16156 insert the current page number
16159 insert the current date and time in common log format
16165 insert the printer name
16168 insert the username
16171 A value of the empty string disables page logging. The string @code{%p
16172 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
16173 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
16176 Defaults to @samp{""}.
16179 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
16180 Passes the specified environment variable(s) to child processes; a list
16183 Defaults to @samp{()}.
16186 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
16187 Specifies named access control policies.
16189 Available @code{policy-configuration} fields are:
16191 @deftypevr {@code{policy-configuration} parameter} string name
16192 Name of the policy.
16195 @deftypevr {@code{policy-configuration} parameter} string job-private-access
16196 Specifies an access list for a job's private values. @code{@@ACL} maps
16197 to the printer's requesting-user-name-allowed or
16198 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
16199 owner. @code{@@SYSTEM} maps to the groups listed for the
16200 @code{system-group} field of the @code{files-config} configuration,
16201 which is reified into the @code{cups-files.conf(5)} file. Other
16202 possible elements of the access list include specific user names, and
16203 @code{@@@var{group}} to indicate members of a specific group. The
16204 access list may also be simply @code{all} or @code{default}.
16206 Defaults to @samp{"@@OWNER @@SYSTEM"}.
16209 @deftypevr {@code{policy-configuration} parameter} string job-private-values
16210 Specifies the list of job values to make private, or @code{all},
16211 @code{default}, or @code{none}.
16213 Defaults to @samp{"job-name job-originating-host-name
16214 job-originating-user-name phone"}.
16217 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
16218 Specifies an access list for a subscription's private values.
16219 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
16220 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
16221 owner. @code{@@SYSTEM} maps to the groups listed for the
16222 @code{system-group} field of the @code{files-config} configuration,
16223 which is reified into the @code{cups-files.conf(5)} file. Other
16224 possible elements of the access list include specific user names, and
16225 @code{@@@var{group}} to indicate members of a specific group. The
16226 access list may also be simply @code{all} or @code{default}.
16228 Defaults to @samp{"@@OWNER @@SYSTEM"}.
16231 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
16232 Specifies the list of job values to make private, or @code{all},
16233 @code{default}, or @code{none}.
16235 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
16236 notify-subscriber-user-name notify-user-data"}.
16239 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
16240 Access control by IPP operation.
16242 Defaults to @samp{()}.
16246 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
16247 Specifies whether job files (documents) are preserved after a job is
16248 printed. If a numeric value is specified, job files are preserved for
16249 the indicated number of seconds after printing. Otherwise a boolean
16250 value applies indefinitely.
16252 Defaults to @samp{86400}.
16255 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
16256 Specifies whether the job history is preserved after a job is printed.
16257 If a numeric value is specified, the job history is preserved for the
16258 indicated number of seconds after printing. If @code{#t}, the job
16259 history is preserved until the MaxJobs limit is reached.
16261 Defaults to @samp{#t}.
16264 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
16265 Specifies the amount of time to wait for job completion before
16266 restarting the scheduler.
16268 Defaults to @samp{30}.
16271 @deftypevr {@code{cups-configuration} parameter} string rip-cache
16272 Specifies the maximum amount of memory to use when converting documents
16273 into bitmaps for a printer.
16275 Defaults to @samp{"128m"}.
16278 @deftypevr {@code{cups-configuration} parameter} string server-admin
16279 Specifies the email address of the server administrator.
16281 Defaults to @samp{"root@@localhost.localdomain"}.
16284 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
16285 The ServerAlias directive is used for HTTP Host header validation when
16286 clients connect to the scheduler from external interfaces. Using the
16287 special name @code{*} can expose your system to known browser-based DNS
16288 rebinding attacks, even when accessing sites through a firewall. If the
16289 auto-discovery of alternate names does not work, we recommend listing
16290 each alternate name with a ServerAlias directive instead of using
16293 Defaults to @samp{*}.
16296 @deftypevr {@code{cups-configuration} parameter} string server-name
16297 Specifies the fully-qualified host name of the server.
16299 Defaults to @samp{"localhost"}.
16302 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
16303 Specifies what information is included in the Server header of HTTP
16304 responses. @code{None} disables the Server header. @code{ProductOnly}
16305 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
16306 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
16307 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
16308 the output of the @code{uname} command. @code{Full} reports @code{CUPS
16309 2.0.0 (@var{uname}) IPP/2.0}.
16311 Defaults to @samp{Minimal}.
16314 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
16315 Listens on the specified interfaces for encrypted connections. Valid
16316 values are of the form @var{address}:@var{port}, where @var{address} is
16317 either an IPv6 address enclosed in brackets, an IPv4 address, or
16318 @code{*} to indicate all addresses.
16320 Defaults to @samp{()}.
16323 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
16324 Sets encryption options. By default, CUPS only supports encryption
16325 using TLS v1.0 or higher using known secure cipher suites. Security is
16326 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
16327 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
16328 suites, which are required for some older clients. The @code{AllowSSL3} option
16329 enables SSL v3.0, which is required for some older clients that do not support
16330 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
16331 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
16332 protocol version to TLS v1.1.
16334 Defaults to @samp{()}.
16337 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
16338 Specifies whether the scheduler requires clients to strictly adhere to
16339 the IPP specifications.
16341 Defaults to @samp{#f}.
16344 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
16345 Specifies the HTTP request timeout, in seconds.
16347 Defaults to @samp{300}.
16351 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
16352 Specifies whether the web interface is enabled.
16354 Defaults to @samp{#f}.
16357 At this point you're probably thinking ``oh dear, Guix manual, I like
16358 you but you can stop already with the configuration options''. Indeed.
16359 However, one more point: it could be that you have an existing
16360 @code{cupsd.conf} that you want to use. In that case, you can pass an
16361 @code{opaque-cups-configuration} as the configuration of a
16362 @code{cups-service-type}.
16364 Available @code{opaque-cups-configuration} fields are:
16366 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
16370 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
16371 The contents of the @code{cupsd.conf}, as a string.
16374 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
16375 The contents of the @code{cups-files.conf} file, as a string.
16378 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
16379 strings of the same name, you could instantiate a CUPS service like
16383 (service cups-service-type
16384 (opaque-cups-configuration
16385 (cupsd.conf cupsd.conf)
16386 (cups-files.conf cups-files.conf)))
16390 @node Desktop Services
16391 @subsection Desktop Services
16393 The @code{(gnu services desktop)} module provides services that are
16394 usually useful in the context of a ``desktop'' setup---that is, on a
16395 machine running a graphical display server, possibly with graphical user
16396 interfaces, etc. It also defines services that provide specific desktop
16397 environments like GNOME, Xfce or MATE.
16399 To simplify things, the module defines a variable containing the set of
16400 services that users typically expect on a machine with a graphical
16401 environment and networking:
16403 @defvr {Scheme Variable} %desktop-services
16404 This is a list of services that builds upon @code{%base-services} and
16405 adds or adjusts services for a typical ``desktop'' setup.
16407 In particular, it adds a graphical login manager (@pxref{X Window,
16408 @code{gdm-service-type}}), screen lockers, a network management tool
16409 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
16410 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
16411 energy and color management services, the @code{elogind} login and seat
16412 manager, the Polkit privilege service, the GeoClue location service, the
16413 AccountsService daemon that allows authorized users change system passwords,
16414 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
16415 name service switch service configured to be able to use @code{nss-mdns}
16416 (@pxref{Name Service Switch, mDNS}).
16419 The @code{%desktop-services} variable can be used as the @code{services}
16420 field of an @code{operating-system} declaration (@pxref{operating-system
16421 Reference, @code{services}}).
16423 Additionally, the @code{gnome-desktop-service-type},
16424 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
16425 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
16426 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
16427 services like the backlight adjustment helpers and the power management
16428 utilities are added to the system, extending @code{polkit} and @code{dbus}
16429 appropriately, allowing GNOME to operate with elevated privileges on a
16430 limited number of special-purpose system interfaces. Additionally,
16431 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
16432 metapackage to the system profile. Likewise, adding the Xfce service
16433 not only adds the @code{xfce} metapackage to the system profile, but it
16434 also gives the Thunar file manager the ability to open a ``root-mode''
16435 file management window, if the user authenticates using the
16436 administrator's password via the standard polkit graphical interface.
16437 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
16438 appropriately, allowing MATE to operate with elevated privileges on a
16439 limited number of special-purpose system interfaces. Additionally,
16440 adding a service of type @code{mate-desktop-service-type} adds the MATE
16441 metapackage to the system profile. ``Adding Enlightenment'' means that
16442 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
16443 are set as setuid, allowing Enlightenment's screen locker and other
16444 functionality to work as expected.
16446 The desktop environments in Guix use the Xorg display server by
16447 default. If you'd like to use the newer display server protocol
16448 called Wayland, you need to use the @code{sddm-service} instead of
16449 GDM as the graphical login manager. You should then
16450 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
16451 also try starting GNOME on Wayland manually from a TTY with the
16452 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
16453 gnome-session``. Currently only GNOME has support for Wayland.
16455 @defvr {Scheme Variable} gnome-desktop-service-type
16456 This is the type of the service that adds the @uref{https://www.gnome.org,
16457 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
16458 object (see below).
16460 This service adds the @code{gnome} package to the system profile, and extends
16461 polkit with the actions from @code{gnome-settings-daemon}.
16464 @deftp {Data Type} gnome-desktop-configuration
16465 Configuration record for the GNOME desktop environment.
16468 @item @code{gnome} (default: @code{gnome})
16469 The GNOME package to use.
16473 @defvr {Scheme Variable} xfce-desktop-service-type
16474 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
16475 desktop environment. Its value is an @code{xfce-desktop-configuration} object
16478 This service adds the @code{xfce} package to the system profile, and
16479 extends polkit with the ability for @code{thunar} to manipulate the file
16480 system as root from within a user session, after the user has authenticated
16481 with the administrator's password.
16484 @deftp {Data Type} xfce-desktop-configuration
16485 Configuration record for the Xfce desktop environment.
16488 @item @code{xfce} (default: @code{xfce})
16489 The Xfce package to use.
16493 @deffn {Scheme Variable} mate-desktop-service-type
16494 This is the type of the service that runs the @uref{https://mate-desktop.org/,
16495 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
16496 object (see below).
16498 This service adds the @code{mate} package to the system
16499 profile, and extends polkit with the actions from
16500 @code{mate-settings-daemon}.
16503 @deftp {Data Type} mate-desktop-configuration
16504 Configuration record for the MATE desktop environment.
16507 @item @code{mate} (default: @code{mate})
16508 The MATE package to use.
16512 @deffn {Scheme Variable} enlightenment-desktop-service-type
16513 Return a service that adds the @code{enlightenment} package to the system
16514 profile, and extends dbus with actions from @code{efl}.
16517 @deftp {Data Type} enlightenment-desktop-service-configuration
16519 @item @code{enlightenment} (default: @code{enlightenment})
16520 The enlightenment package to use.
16524 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
16525 the default @code{%desktop-services} variable doesn't include any of
16526 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
16527 @code{%desktop-services} in the @code{services} field of your
16528 @code{operating-system}:
16531 (use-modules (gnu))
16532 (use-service-modules desktop)
16535 ;; cons* adds items to the list given as its last argument.
16536 (services (cons* (service gnome-desktop-service-type)
16537 (service xfce-desktop-service)
16538 %desktop-services))
16542 These desktop environments will then be available as options in the
16543 graphical login window.
16545 The actual service definitions included in @code{%desktop-services} and
16546 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
16547 are described below.
16549 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
16550 Return a service that runs the ``system bus'', using @var{dbus}, with
16551 support for @var{services}.
16553 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
16554 facility. Its system bus is used to allow system services to communicate
16555 and to be notified of system-wide events.
16557 @var{services} must be a list of packages that provide an
16558 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
16559 and policy files. For example, to allow avahi-daemon to use the system bus,
16560 @var{services} must be equal to @code{(list avahi)}.
16563 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
16564 Return a service that runs the @code{elogind} login and
16565 seat management daemon. @uref{https://github.com/elogind/elogind,
16566 Elogind} exposes a D-Bus interface that can be used to know which users
16567 are logged in, know what kind of sessions they have open, suspend the
16568 system, inhibit system suspend, reboot the system, and other tasks.
16570 Elogind handles most system-level power events for a computer, for
16571 example suspending the system when a lid is closed, or shutting it down
16572 when the power button is pressed.
16574 The @var{config} keyword argument specifies the configuration for
16575 elogind, and should be the result of an @code{(elogind-configuration
16576 (@var{parameter} @var{value})...)} invocation. Available parameters and
16577 their default values are:
16580 @item kill-user-processes?
16582 @item kill-only-users
16584 @item kill-exclude-users
16586 @item inhibit-delay-max-seconds
16588 @item handle-power-key
16590 @item handle-suspend-key
16592 @item handle-hibernate-key
16594 @item handle-lid-switch
16596 @item handle-lid-switch-docked
16598 @item power-key-ignore-inhibited?
16600 @item suspend-key-ignore-inhibited?
16602 @item hibernate-key-ignore-inhibited?
16604 @item lid-switch-ignore-inhibited?
16606 @item holdoff-timeout-seconds
16610 @item idle-action-seconds
16612 @item runtime-directory-size-percent
16614 @item runtime-directory-size
16618 @item suspend-state
16619 @code{("mem" "standby" "freeze")}
16622 @item hibernate-state
16624 @item hibernate-mode
16625 @code{("platform" "shutdown")}
16626 @item hybrid-sleep-state
16628 @item hybrid-sleep-mode
16629 @code{("suspend" "platform" "shutdown")}
16633 @deffn {Scheme Procedure} accountsservice-service @
16634 [#:accountsservice @var{accountsservice}]
16635 Return a service that runs AccountsService, a system service that can
16636 list available accounts, change their passwords, and so on.
16637 AccountsService integrates with PolicyKit to enable unprivileged users
16638 to acquire the capability to modify their system configuration.
16639 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
16640 accountsservice web site} for more information.
16642 The @var{accountsservice} keyword argument is the @code{accountsservice}
16643 package to expose as a service.
16646 @deffn {Scheme Procedure} polkit-service @
16647 [#:polkit @var{polkit}]
16648 Return a service that runs the
16649 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
16650 management service}, which allows system administrators to grant access to
16651 privileged operations in a structured way. By querying the Polkit service, a
16652 privileged system component can know when it should grant additional
16653 capabilities to ordinary users. For example, an ordinary user can be granted
16654 the capability to suspend the system if the user is logged in locally.
16657 @defvr {Scheme Variable} polkit-wheel-service
16658 Service that adds the @code{wheel} group as admins to the Polkit
16659 service. This makes it so that users in the @code{wheel} group are queried
16660 for their own passwords when performing administrative actions instead of
16661 @code{root}'s, similar to the behaviour used by @code{sudo}.
16664 @defvr {Scheme Variable} upower-service-type
16665 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
16666 system-wide monitor for power consumption and battery levels, with the given
16667 configuration settings.
16669 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
16670 notably used by GNOME.
16673 @deftp {Data Type} upower-configuration
16674 Data type representation the configuration for UPower.
16678 @item @code{upower} (default: @var{upower})
16679 Package to use for @code{upower}.
16681 @item @code{watts-up-pro?} (default: @code{#f})
16682 Enable the Watts Up Pro device.
16684 @item @code{poll-batteries?} (default: @code{#t})
16685 Enable polling the kernel for battery level changes.
16687 @item @code{ignore-lid?} (default: @code{#f})
16688 Ignore the lid state, this can be useful if it's incorrect on a device.
16690 @item @code{use-percentage-for-policy?} (default: @code{#f})
16691 Whether battery percentage based policy should be used. The default is to use
16692 the time left, change to @code{#t} to use the percentage.
16694 @item @code{percentage-low} (default: @code{10})
16695 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16696 at which the battery is considered low.
16698 @item @code{percentage-critical} (default: @code{3})
16699 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16700 at which the battery is considered critical.
16702 @item @code{percentage-action} (default: @code{2})
16703 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16704 at which action will be taken.
16706 @item @code{time-low} (default: @code{1200})
16707 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16708 seconds at which the battery is considered low.
16710 @item @code{time-critical} (default: @code{300})
16711 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16712 seconds at which the battery is considered critical.
16714 @item @code{time-action} (default: @code{120})
16715 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16716 seconds at which action will be taken.
16718 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
16719 The action taken when @code{percentage-action} or @code{time-action} is
16720 reached (depending on the configuration of @code{use-percentage-for-policy?}).
16722 Possible values are:
16732 @code{'hybrid-sleep}.
16738 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
16739 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
16740 UDisks}, a @dfn{disk management} daemon that provides user interfaces
16741 with notifications and ways to mount/unmount disks. Programs that talk
16742 to UDisks include the @command{udisksctl} command, part of UDisks, and
16743 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
16744 it will only be able to use the file-system utilities installed in the
16745 system profile. For example if you want to be able to mount NTFS
16746 file-systems in read and write fashion, you'll need to have
16747 @code{ntfs-3g} installed system-wide.
16750 @deffn {Scheme Variable} colord-service-type
16751 This is the type of the service that runs @command{colord}, a system
16752 service with a D-Bus
16753 interface to manage the color profiles of input and output devices such as
16754 screens and scanners. It is notably used by the GNOME Color Manager graphical
16755 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
16756 site} for more information.
16759 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
16760 Return a configuration allowing an application to access GeoClue
16761 location data. @var{name} is the Desktop ID of the application, without
16762 the @code{.desktop} part. If @var{allowed?} is true, the application
16763 will have access to location information by default. The boolean
16764 @var{system?} value indicates whether an application is a system component
16765 or not. Finally @var{users} is a list of UIDs of all users for which
16766 this application is allowed location info access. An empty users list
16767 means that all users are allowed.
16770 @cindex scanner access
16771 @deffn {Scheme Procedure} sane-service-type
16772 This service provides access to scanners @i{via}
16773 @uref{http://www.sane-project.org, SANE} by installing the necessary udev
16777 @defvr {Scheme Variable} %standard-geoclue-applications
16778 The standard list of well-known GeoClue application configurations,
16779 granting authority to the GNOME date-and-time utility to ask for the
16780 current location in order to set the time zone, and allowing the
16781 IceCat and Epiphany web browsers to request location information.
16782 IceCat and Epiphany both query the user before allowing a web page to
16783 know the user's location.
16786 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
16787 [#:whitelist '()] @
16788 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
16789 [#:submit-data? #f]
16790 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
16791 [#:submission-nick "geoclue"] @
16792 [#:applications %standard-geoclue-applications]
16793 Return a service that runs the GeoClue location service. This service
16794 provides a D-Bus interface to allow applications to request access to a
16795 user's physical location, and optionally to add information to online
16796 location databases. See
16797 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
16798 web site} for more information.
16801 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
16802 [@w{#:auto-enable? #f}]
16803 Return a service that runs the @command{bluetoothd} daemon, which
16804 manages all the Bluetooth devices and provides a number of D-Bus
16805 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
16806 powered automatically at boot, which can be useful when using a
16807 bluetooth keyboard or mouse.
16809 Users need to be in the @code{lp} group to access the D-Bus service.
16812 @defvr {Scheme Variable} gnome-keyring-service-type
16813 This is the type of the service that adds the
16814 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
16815 value is a @code{gnome-keyring-configuration} object (see below).
16817 This service adds the @code{gnome-keyring} package to the system profile
16818 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
16819 a user's login keyring when they log in or setting its password with passwd.
16822 @deftp {Data Type} gnome-keyring-configuration
16823 Configuration record for the GNOME Keyring service.
16826 @item @code{keyring} (default: @code{gnome-keyring})
16827 The GNOME keyring package to use.
16829 @item @code{pam-services}
16830 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
16831 services to extend, where @var{service} is the name of an existing
16832 service to extend and @var{kind} is one of @code{login} or
16835 If @code{login} is given, it adds an optional
16836 @code{pam_gnome_keyring.so} to the auth block without arguments and to
16837 the session block with @code{auto_start}. If @code{passwd} is given, it
16838 adds an optional @code{pam_gnome_keyring.so} to the password block
16841 By default, this field contains ``gdm-password'' with the value @code{login}
16842 and ``passwd'' is with the value @code{passwd}.
16847 @node Sound Services
16848 @subsection Sound Services
16850 @cindex sound support
16852 @cindex PulseAudio, sound support
16854 The @code{(gnu services sound)} module provides a service to configure the
16855 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
16856 preferred ALSA output driver.
16858 @deffn {Scheme Variable} alsa-service-type
16859 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
16860 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
16861 configuration file. The value for this type is a @command{alsa-configuration}
16862 record as in this example:
16865 (service alsa-service-type)
16868 See below for details about @code{alsa-configuration}.
16871 @deftp {Data Type} alsa-configuration
16872 Data type representing the configuration for @code{alsa-service}.
16875 @item @code{alsa-plugins} (default: @var{alsa-plugins})
16876 @code{alsa-plugins} package to use.
16878 @item @code{pulseaudio?} (default: @var{#t})
16879 Whether ALSA applications should transparently be made to use the
16880 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
16882 Using PulseAudio allows you to run several sound-producing applications
16883 at the same time and to individual control them @i{via}
16884 @command{pavucontrol}, among other things.
16886 @item @code{extra-options} (default: @var{""})
16887 String to append to the @file{/etc/asound.conf} file.
16892 Individual users who want to override the system configuration of ALSA can do
16893 it with the @file{~/.asoundrc} file:
16896 # In guix, we have to specify the absolute path for plugins.
16898 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
16901 # Routing ALSA to jack:
16902 # <http://jackaudio.org/faq/routing_alsa.html>.
16906 0 system:playback_1
16907 1 system:playback_2
16924 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
16927 @deffn {Scheme Variable} pulseaudio-service-type
16928 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
16929 sound server. It exists to allow system overrides of the default settings
16930 via @code{pulseaudio-configuration}, see below.
16933 This service overrides per-user configuration files. If you want
16934 PulseAudio to honor configuraton files in @file{~/.config/pulse} you
16935 have to unset the environment variables @env{PULSE_CONFIG} and
16936 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
16940 This service on its own does not ensure, that the @code{pulseaudio} package
16941 exists on your machine. It merely adds configuration files for it, as
16942 detailed below. In the (admittedly unlikely) case, that you find yourself
16943 without a @code{pulseaudio} package, consider enabling it through the
16944 @code{alsa-service-type} above.
16948 @deftp {Data Type} pulseaudio-configuration
16949 Data type representing the configuration for @code{pulseaudio-service}.
16952 @item @var{client-conf} (default: @code{'()})
16953 List of settings to set in @file{client.conf}.
16954 Accepts a list of strings or a symbol-value pairs. A string will be
16955 inserted as-is with a newline added. A pair will be formatted as
16956 ``key = value'', again with a newline added.
16958 @item @var{daemon-conf} (default: @code{'((flat-volumes . no))})
16959 List of settings to set in @file{daemon.conf}, formatted just like
16962 @item @var{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
16963 Script file to use as as @file{default.pa}.
16965 @item @var{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
16966 Script file to use as as @file{system.pa}.
16970 @deffn {Scheme Variable} ladspa-service-type
16971 This service sets the @var{LADSPA_PATH} variable, so that programs, which
16972 respect it, e.g. PulseAudio, can load LADSPA plugins.
16974 The following example will setup the service to enable modules from the
16975 @code{swh-plugins} package:
16978 (service ladspa-service-type
16979 (ladspa-configuration (plugins (list swh-plugins))))
16982 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
16987 @node Database Services
16988 @subsection Database Services
16992 The @code{(gnu services databases)} module provides the following services.
16994 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
16995 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
16996 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
16997 Return a service that runs @var{postgresql}, the PostgreSQL database
17000 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
17001 creates a database cluster with @var{locale} as the default
17002 locale, stored in @var{data-directory}. It then listens on @var{port}.
17004 @cindex postgresql extension-packages
17005 Additional extensions are loaded from packages listed in
17006 @var{extension-packages}. Extensions are available at runtime. For instance,
17007 to create a geographic database using the @code{postgis} extension, a user can
17008 configure the postgresql-service as in this example:
17012 (use-package-modules databases geo)
17016 ;; postgresql is required to run `psql' but postgis is not required for
17017 ;; proper operation.
17018 (packages (cons* postgresql %base-packages))
17021 (postgresql-service #:extension-packages (list postgis))
17025 Then the extension becomes visible and you can initialise an empty geographic
17026 database in this way:
17030 > create database postgistest;
17031 > \connect postgistest;
17032 > create extension postgis;
17033 > create extension postgis_topology;
17036 There is no need to add this field for contrib extensions such as hstore or
17037 dblink as they are already loadable by postgresql. This field is only
17038 required to add extensions provided by other packages.
17041 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
17042 Return a service that runs @command{mysqld}, the MySQL or MariaDB
17045 The optional @var{config} argument specifies the configuration for
17046 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
17049 @deftp {Data Type} mysql-configuration
17050 Data type representing the configuration of @var{mysql-service}.
17053 @item @code{mysql} (default: @var{mariadb})
17054 Package object of the MySQL database server, can be either @var{mariadb}
17057 For MySQL, a temporary root password will be displayed at activation time.
17058 For MariaDB, the root password is empty.
17060 @item @code{port} (default: @code{3306})
17061 TCP port on which the database server listens for incoming connections.
17065 @defvr {Scheme Variable} memcached-service-type
17066 This is the service type for the @uref{https://memcached.org/,
17067 Memcached} service, which provides a distributed in memory cache. The
17068 value for the service type is a @code{memcached-configuration} object.
17072 (service memcached-service-type)
17075 @deftp {Data Type} memcached-configuration
17076 Data type representing the configuration of memcached.
17079 @item @code{memcached} (default: @code{memcached})
17080 The Memcached package to use.
17082 @item @code{interfaces} (default: @code{'("0.0.0.0")})
17083 Network interfaces on which to listen.
17085 @item @code{tcp-port} (default: @code{11211})
17086 Port on which to accept connections on,
17088 @item @code{udp-port} (default: @code{11211})
17089 Port on which to accept UDP connections on, a value of 0 will disable
17090 listening on a UDP socket.
17092 @item @code{additional-options} (default: @code{'()})
17093 Additional command line options to pass to @code{memcached}.
17097 @defvr {Scheme Variable} mongodb-service-type
17098 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
17099 The value for the service type is a @code{mongodb-configuration} object.
17103 (service mongodb-service-type)
17106 @deftp {Data Type} mongodb-configuration
17107 Data type representing the configuration of mongodb.
17110 @item @code{mongodb} (default: @code{mongodb})
17111 The MongoDB package to use.
17113 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
17114 The configuration file for MongoDB.
17116 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
17117 This value is used to create the directory, so that it exists and is
17118 owned by the mongodb user. It should match the data-directory which
17119 MongoDB is configured to use through the configuration file.
17123 @defvr {Scheme Variable} redis-service-type
17124 This is the service type for the @uref{https://redis.io/, Redis}
17125 key/value store, whose value is a @code{redis-configuration} object.
17128 @deftp {Data Type} redis-configuration
17129 Data type representing the configuration of redis.
17132 @item @code{redis} (default: @code{redis})
17133 The Redis package to use.
17135 @item @code{bind} (default: @code{"127.0.0.1"})
17136 Network interface on which to listen.
17138 @item @code{port} (default: @code{6379})
17139 Port on which to accept connections on, a value of 0 will disable
17140 listening on a TCP socket.
17142 @item @code{working-directory} (default: @code{"/var/lib/redis"})
17143 Directory in which to store the database and related files.
17147 @node Mail Services
17148 @subsection Mail Services
17152 The @code{(gnu services mail)} module provides Guix service definitions
17153 for email services: IMAP, POP3, and LMTP servers, as well as mail
17154 transport agents (MTAs). Lots of acronyms! These services are detailed
17155 in the subsections below.
17157 @subsubheading Dovecot Service
17159 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
17160 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
17163 By default, Dovecot does not need much configuration; the default
17164 configuration object created by @code{(dovecot-configuration)} will
17165 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
17166 certificate will be generated for TLS-protected connections, though
17167 Dovecot will also listen on cleartext ports by default. There are a
17168 number of options, though, which mail administrators might need to change,
17169 and as is the case with other services, Guix allows the system
17170 administrator to specify these parameters via a uniform Scheme interface.
17172 For example, to specify that mail is located at @code{maildir~/.mail},
17173 one would instantiate the Dovecot service like this:
17176 (dovecot-service #:config
17177 (dovecot-configuration
17178 (mail-location "maildir:~/.mail")))
17181 The available configuration parameters follow. Each parameter
17182 definition is preceded by its type; for example, @samp{string-list foo}
17183 indicates that the @code{foo} parameter should be specified as a list of
17184 strings. There is also a way to specify the configuration as a string,
17185 if you have an old @code{dovecot.conf} file that you want to port over
17186 from some other system; see the end for more details.
17188 @c The following documentation was initially generated by
17189 @c (generate-documentation) in (gnu services mail). Manually maintained
17190 @c documentation is better, so we shouldn't hesitate to edit below as
17191 @c needed. However if the change you want to make to this documentation
17192 @c can be done in an automated way, it's probably easier to change
17193 @c (generate-documentation) than to make it below and have to deal with
17194 @c the churn as dovecot updates.
17196 Available @code{dovecot-configuration} fields are:
17198 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
17199 The dovecot package.
17202 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
17203 A list of IPs or hosts where to listen for connections. @samp{*}
17204 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
17205 interfaces. If you want to specify non-default ports or anything more
17206 complex, customize the address and port fields of the
17207 @samp{inet-listener} of the specific services you are interested in.
17210 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
17211 List of protocols we want to serve. Available protocols include
17212 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
17214 Available @code{protocol-configuration} fields are:
17216 @deftypevr {@code{protocol-configuration} parameter} string name
17217 The name of the protocol.
17220 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
17221 UNIX socket path to the master authentication server to find users.
17222 This is used by imap (for shared users) and lda.
17223 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
17226 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
17227 Space separated list of plugins to load.
17230 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
17231 Maximum number of IMAP connections allowed for a user from each IP
17232 address. NOTE: The username is compared case-sensitively.
17233 Defaults to @samp{10}.
17238 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
17239 List of services to enable. Available services include @samp{imap},
17240 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
17243 Available @code{service-configuration} fields are:
17245 @deftypevr {@code{service-configuration} parameter} string kind
17246 The service kind. Valid values include @code{director},
17247 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
17248 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
17249 @code{tcpwrap}, @code{quota-warning}, or anything else.
17252 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
17253 Listeners for the service. A listener is either a
17254 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
17255 an @code{inet-listener-configuration}.
17256 Defaults to @samp{()}.
17258 Available @code{unix-listener-configuration} fields are:
17260 @deftypevr {@code{unix-listener-configuration} parameter} string path
17261 Path to the file, relative to @code{base-dir} field. This is also used as
17265 @deftypevr {@code{unix-listener-configuration} parameter} string mode
17266 The access mode for the socket.
17267 Defaults to @samp{"0600"}.
17270 @deftypevr {@code{unix-listener-configuration} parameter} string user
17271 The user to own the socket.
17272 Defaults to @samp{""}.
17275 @deftypevr {@code{unix-listener-configuration} parameter} string group
17276 The group to own the socket.
17277 Defaults to @samp{""}.
17281 Available @code{fifo-listener-configuration} fields are:
17283 @deftypevr {@code{fifo-listener-configuration} parameter} string path
17284 Path to the file, relative to @code{base-dir} field. This is also used as
17288 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
17289 The access mode for the socket.
17290 Defaults to @samp{"0600"}.
17293 @deftypevr {@code{fifo-listener-configuration} parameter} string user
17294 The user to own the socket.
17295 Defaults to @samp{""}.
17298 @deftypevr {@code{fifo-listener-configuration} parameter} string group
17299 The group to own the socket.
17300 Defaults to @samp{""}.
17304 Available @code{inet-listener-configuration} fields are:
17306 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
17307 The protocol to listen for.
17310 @deftypevr {@code{inet-listener-configuration} parameter} string address
17311 The address on which to listen, or empty for all addresses.
17312 Defaults to @samp{""}.
17315 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
17316 The port on which to listen.
17319 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
17320 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
17322 Defaults to @samp{#t}.
17327 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
17328 Maximum number of simultaneous client connections per process. Once
17329 this number of connections is received, the next incoming connection
17330 will prompt Dovecot to spawn another process. If set to 0,
17331 @code{default-client-limit} is used instead.
17333 Defaults to @samp{0}.
17337 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
17338 Number of connections to handle before starting a new process.
17339 Typically the only useful values are 0 (unlimited) or 1. 1 is more
17340 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
17341 Defaults to @samp{1}.
17345 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
17346 Maximum number of processes that can exist for this service. If set to
17347 0, @code{default-process-limit} is used instead.
17349 Defaults to @samp{0}.
17353 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
17354 Number of processes to always keep waiting for more connections.
17355 Defaults to @samp{0}.
17358 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
17359 If you set @samp{service-count 0}, you probably need to grow
17361 Defaults to @samp{256000000}.
17366 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
17367 Dict configuration, as created by the @code{dict-configuration}
17370 Available @code{dict-configuration} fields are:
17372 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
17373 A list of key-value pairs that this dict should hold.
17374 Defaults to @samp{()}.
17379 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
17380 A list of passdb configurations, each one created by the
17381 @code{passdb-configuration} constructor.
17383 Available @code{passdb-configuration} fields are:
17385 @deftypevr {@code{passdb-configuration} parameter} string driver
17386 The driver that the passdb should use. Valid values include
17387 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
17389 Defaults to @samp{"pam"}.
17392 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
17393 Space separated list of arguments to the passdb driver.
17394 Defaults to @samp{""}.
17399 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
17400 List of userdb configurations, each one created by the
17401 @code{userdb-configuration} constructor.
17403 Available @code{userdb-configuration} fields are:
17405 @deftypevr {@code{userdb-configuration} parameter} string driver
17406 The driver that the userdb should use. Valid values include
17407 @samp{passwd} and @samp{static}.
17408 Defaults to @samp{"passwd"}.
17411 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
17412 Space separated list of arguments to the userdb driver.
17413 Defaults to @samp{""}.
17416 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
17417 Override fields from passwd.
17418 Defaults to @samp{()}.
17423 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
17424 Plug-in configuration, created by the @code{plugin-configuration}
17428 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
17429 List of namespaces. Each item in the list is created by the
17430 @code{namespace-configuration} constructor.
17432 Available @code{namespace-configuration} fields are:
17434 @deftypevr {@code{namespace-configuration} parameter} string name
17435 Name for this namespace.
17438 @deftypevr {@code{namespace-configuration} parameter} string type
17439 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
17440 Defaults to @samp{"private"}.
17443 @deftypevr {@code{namespace-configuration} parameter} string separator
17444 Hierarchy separator to use. You should use the same separator for
17445 all namespaces or some clients get confused. @samp{/} is usually a good
17446 one. The default however depends on the underlying mail storage
17448 Defaults to @samp{""}.
17451 @deftypevr {@code{namespace-configuration} parameter} string prefix
17452 Prefix required to access this namespace. This needs to be
17453 different for all namespaces. For example @samp{Public/}.
17454 Defaults to @samp{""}.
17457 @deftypevr {@code{namespace-configuration} parameter} string location
17458 Physical location of the mailbox. This is in the same format as
17459 mail_location, which is also the default for it.
17460 Defaults to @samp{""}.
17463 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
17464 There can be only one INBOX, and this setting defines which
17466 Defaults to @samp{#f}.
17469 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
17470 If namespace is hidden, it's not advertised to clients via NAMESPACE
17471 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
17472 useful when converting from another server with different namespaces
17473 which you want to deprecate but still keep working. For example you can
17474 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
17476 Defaults to @samp{#f}.
17479 @deftypevr {@code{namespace-configuration} parameter} boolean list?
17480 Show the mailboxes under this namespace with the LIST command. This
17481 makes the namespace visible for clients that do not support the NAMESPACE
17482 extension. The special @code{children} value lists child mailboxes, but
17483 hides the namespace prefix.
17484 Defaults to @samp{#t}.
17487 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
17488 Namespace handles its own subscriptions. If set to @code{#f}, the
17489 parent namespace handles them. The empty prefix should always have this
17491 Defaults to @samp{#t}.
17494 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
17495 List of predefined mailboxes in this namespace.
17496 Defaults to @samp{()}.
17498 Available @code{mailbox-configuration} fields are:
17500 @deftypevr {@code{mailbox-configuration} parameter} string name
17501 Name for this mailbox.
17504 @deftypevr {@code{mailbox-configuration} parameter} string auto
17505 @samp{create} will automatically create this mailbox.
17506 @samp{subscribe} will both create and subscribe to the mailbox.
17507 Defaults to @samp{"no"}.
17510 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
17511 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
17512 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
17513 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
17514 Defaults to @samp{()}.
17521 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
17522 Base directory where to store runtime data.
17523 Defaults to @samp{"/var/run/dovecot/"}.
17526 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
17527 Greeting message for clients.
17528 Defaults to @samp{"Dovecot ready."}.
17531 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
17532 List of trusted network ranges. Connections from these IPs are
17533 allowed to override their IP addresses and ports (for logging and for
17534 authentication checks). @samp{disable-plaintext-auth} is also ignored
17535 for these networks. Typically you would specify your IMAP proxy servers
17537 Defaults to @samp{()}.
17540 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
17541 List of login access check sockets (e.g.@: tcpwrap).
17542 Defaults to @samp{()}.
17545 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
17546 Show more verbose process titles (in ps). Currently shows user name
17547 and IP address. Useful for seeing who is actually using the IMAP
17548 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
17550 Defaults to @samp{#f}.
17553 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
17554 Should all processes be killed when Dovecot master process shuts down.
17555 Setting this to @code{#f} means that Dovecot can be upgraded without
17556 forcing existing client connections to close (although that could also
17557 be a problem if the upgrade is e.g.@: due to a security fix).
17558 Defaults to @samp{#t}.
17561 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
17562 If non-zero, run mail commands via this many connections to doveadm
17563 server, instead of running them directly in the same process.
17564 Defaults to @samp{0}.
17567 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
17568 UNIX socket or host:port used for connecting to doveadm server.
17569 Defaults to @samp{"doveadm-server"}.
17572 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
17573 List of environment variables that are preserved on Dovecot startup
17574 and passed down to all of its child processes. You can also give
17575 key=value pairs to always set specific settings.
17578 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
17579 Disable LOGIN command and all other plaintext authentications unless
17580 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
17581 matches the local IP (i.e.@: you're connecting from the same computer),
17582 the connection is considered secure and plaintext authentication is
17583 allowed. See also ssl=required setting.
17584 Defaults to @samp{#t}.
17587 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
17588 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
17589 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
17590 for caching to be used.
17591 Defaults to @samp{0}.
17594 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
17595 Time to live for cached data. After TTL expires the cached record
17596 is no longer used, *except* if the main database lookup returns internal
17597 failure. We also try to handle password changes automatically: If
17598 user's previous authentication was successful, but this one wasn't, the
17599 cache isn't used. For now this works only with plaintext
17601 Defaults to @samp{"1 hour"}.
17604 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
17605 TTL for negative hits (user not found, password mismatch).
17606 0 disables caching them completely.
17607 Defaults to @samp{"1 hour"}.
17610 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
17611 List of realms for SASL authentication mechanisms that need them.
17612 You can leave it empty if you don't want to support multiple realms.
17613 Many clients simply use the first one listed here, so keep the default
17615 Defaults to @samp{()}.
17618 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
17619 Default realm/domain to use if none was specified. This is used for
17620 both SASL realms and appending @@domain to username in plaintext
17622 Defaults to @samp{""}.
17625 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
17626 List of allowed characters in username. If the user-given username
17627 contains a character not listed in here, the login automatically fails.
17628 This is just an extra check to make sure user can't exploit any
17629 potential quote escaping vulnerabilities with SQL/LDAP databases. If
17630 you want to allow all characters, set this value to empty.
17631 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
17634 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
17635 Username character translations before it's looked up from
17636 databases. The value contains series of from -> to characters. For
17637 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
17638 translated to @samp{@@}.
17639 Defaults to @samp{""}.
17642 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
17643 Username formatting before it's looked up from databases. You can
17644 use the standard variables here, e.g.@: %Lu would lowercase the username,
17645 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
17646 change the @samp{@@} into @samp{-AT-}. This translation is done after
17647 @samp{auth-username-translation} changes.
17648 Defaults to @samp{"%Lu"}.
17651 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
17652 If you want to allow master users to log in by specifying the master
17653 username within the normal username string (i.e.@: not using SASL
17654 mechanism's support for it), you can specify the separator character
17655 here. The format is then <username><separator><master username>.
17656 UW-IMAP uses @samp{*} as the separator, so that could be a good
17658 Defaults to @samp{""}.
17661 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
17662 Username to use for users logging in with ANONYMOUS SASL
17664 Defaults to @samp{"anonymous"}.
17667 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
17668 Maximum number of dovecot-auth worker processes. They're used to
17669 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
17670 They're automatically created and destroyed as needed.
17671 Defaults to @samp{30}.
17674 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
17675 Host name to use in GSSAPI principal names. The default is to use
17676 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
17677 allow all keytab entries.
17678 Defaults to @samp{""}.
17681 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
17682 Kerberos keytab to use for the GSSAPI mechanism. Will use the
17683 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
17684 need to change the auth service to run as root to be able to read this
17686 Defaults to @samp{""}.
17689 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
17690 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
17691 and @samp{ntlm-auth} helper.
17692 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
17693 Defaults to @samp{#f}.
17696 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
17697 Path for Samba's @samp{ntlm-auth} helper binary.
17698 Defaults to @samp{"/usr/bin/ntlm_auth"}.
17701 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
17702 Time to delay before replying to failed authentications.
17703 Defaults to @samp{"2 secs"}.
17706 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
17707 Require a valid SSL client certificate or the authentication
17709 Defaults to @samp{#f}.
17712 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
17713 Take the username from client's SSL certificate, using
17714 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
17716 Defaults to @samp{#f}.
17719 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
17720 List of wanted authentication mechanisms. Supported mechanisms are:
17721 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
17722 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
17723 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
17724 @samp{disable-plaintext-auth} setting.
17727 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
17728 List of IPs or hostnames to all director servers, including ourself.
17729 Ports can be specified as ip:port. The default port is the same as what
17730 director service's @samp{inet-listener} is using.
17731 Defaults to @samp{()}.
17734 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
17735 List of IPs or hostnames to all backend mail servers. Ranges are
17736 allowed too, like 10.0.0.10-10.0.0.30.
17737 Defaults to @samp{()}.
17740 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
17741 How long to redirect users to a specific server after it no longer
17742 has any connections.
17743 Defaults to @samp{"15 min"}.
17746 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
17747 How the username is translated before being hashed. Useful values
17748 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
17749 are shared within domain.
17750 Defaults to @samp{"%Lu"}.
17753 @deftypevr {@code{dovecot-configuration} parameter} string log-path
17754 Log file to use for error messages. @samp{syslog} logs to syslog,
17755 @samp{/dev/stderr} logs to stderr.
17756 Defaults to @samp{"syslog"}.
17759 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
17760 Log file to use for informational messages. Defaults to
17762 Defaults to @samp{""}.
17765 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
17766 Log file to use for debug messages. Defaults to
17767 @samp{info-log-path}.
17768 Defaults to @samp{""}.
17771 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
17772 Syslog facility to use if you're logging to syslog. Usually if you
17773 don't want to use @samp{mail}, you'll use local0..local7. Also other
17774 standard facilities are supported.
17775 Defaults to @samp{"mail"}.
17778 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
17779 Log unsuccessful authentication attempts and the reasons why they
17781 Defaults to @samp{#f}.
17784 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
17785 In case of password mismatches, log the attempted password. Valid
17786 values are no, plain and sha1. sha1 can be useful for detecting brute
17787 force password attempts vs. user simply trying the same password over
17788 and over again. You can also truncate the value to n chars by appending
17789 ":n" (e.g.@: sha1:6).
17790 Defaults to @samp{"no"}.
17793 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
17794 Even more verbose logging for debugging purposes. Shows for example
17796 Defaults to @samp{#f}.
17799 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
17800 In case of password mismatches, log the passwords and used scheme so
17801 the problem can be debugged. Enabling this also enables
17803 Defaults to @samp{#f}.
17806 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
17807 Enable mail process debugging. This can help you figure out why
17808 Dovecot isn't finding your mails.
17809 Defaults to @samp{#f}.
17812 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
17813 Show protocol level SSL errors.
17814 Defaults to @samp{#f}.
17817 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
17818 Prefix for each line written to log file. % codes are in
17819 strftime(3) format.
17820 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
17823 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
17824 List of elements we want to log. The elements which have a
17825 non-empty variable value are joined together to form a comma-separated
17829 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
17830 Login log format. %s contains @samp{login-log-format-elements}
17831 string, %$ contains the data we want to log.
17832 Defaults to @samp{"%$: %s"}.
17835 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
17836 Log prefix for mail processes. See doc/wiki/Variables.txt for list
17837 of possible variables you can use.
17838 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
17841 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
17842 Format to use for logging mail deliveries. You can use variables:
17845 Delivery status message (e.g.@: @samp{saved to INBOX})
17857 Defaults to @samp{"msgid=%m: %$"}.
17860 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
17861 Location for users' mailboxes. The default is empty, which means
17862 that Dovecot tries to find the mailboxes automatically. This won't work
17863 if the user doesn't yet have any mail, so you should explicitly tell
17864 Dovecot the full location.
17866 If you're using mbox, giving a path to the INBOX
17867 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
17868 where the other mailboxes are kept. This is called the @emph{root mail
17869 directory}, and it must be the first path given in the
17870 @samp{mail-location} setting.
17872 There are a few special variables you can use, e.g.:
17878 user part in user@@domain, same as %u if there's no domain
17880 domain part in user@@domain, empty if there's no domain
17885 See doc/wiki/Variables.txt for full list. Some examples:
17887 @item maildir:~/Maildir
17888 @item mbox:~/mail:INBOX=/var/mail/%u
17889 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
17891 Defaults to @samp{""}.
17894 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
17895 System user and group used to access mails. If you use multiple,
17896 userdb can override these by returning uid or gid fields. You can use
17897 either numbers or names. <doc/wiki/UserIds.txt>.
17898 Defaults to @samp{""}.
17901 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
17903 Defaults to @samp{""}.
17906 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
17907 Group to enable temporarily for privileged operations. Currently
17908 this is used only with INBOX when either its initial creation or
17909 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
17911 Defaults to @samp{""}.
17914 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
17915 Grant access to these supplementary groups for mail processes.
17916 Typically these are used to set up access to shared mailboxes. Note
17917 that it may be dangerous to set these if users can create symlinks
17918 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
17919 could allow a user to delete others' mailboxes, or @code{ln -s
17920 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
17924 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
17925 Allow full file system access to clients. There's no access checks
17926 other than what the operating system does for the active UID/GID. It
17927 works with both maildir and mboxes, allowing you to prefix mailboxes
17928 names with e.g.@: @file{/path/} or @file{~user/}.
17929 Defaults to @samp{#f}.
17932 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
17933 Don't use @code{mmap()} at all. This is required if you store indexes to
17934 shared file systems (NFS or clustered file system).
17935 Defaults to @samp{#f}.
17938 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
17939 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
17940 supports @samp{O_EXCL} since version 3, so this should be safe to use
17941 nowadays by default.
17942 Defaults to @samp{#t}.
17945 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
17946 When to use fsync() or fdatasync() calls:
17949 Whenever necessary to avoid losing important data
17951 Useful with e.g.@: NFS when @code{write()}s are delayed
17953 Never use it (best performance, but crashes can lose data).
17955 Defaults to @samp{"optimized"}.
17958 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
17959 Mail storage exists in NFS. Set this to yes to make Dovecot flush
17960 NFS caches whenever needed. If you're using only a single mail server
17962 Defaults to @samp{#f}.
17965 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
17966 Mail index files also exist in NFS. Setting this to yes requires
17967 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
17968 Defaults to @samp{#f}.
17971 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
17972 Locking method for index files. Alternatives are fcntl, flock and
17973 dotlock. Dotlocking uses some tricks which may create more disk I/O
17974 than other locking methods. NFS users: flock doesn't work, remember to
17975 change @samp{mmap-disable}.
17976 Defaults to @samp{"fcntl"}.
17979 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
17980 Directory in which LDA/LMTP temporarily stores incoming mails >128
17982 Defaults to @samp{"/tmp"}.
17985 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
17986 Valid UID range for users. This is mostly to make sure that users can't
17987 log in as daemons or other system users. Note that denying root logins is
17988 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
17990 Defaults to @samp{500}.
17993 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
17995 Defaults to @samp{0}.
17998 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
17999 Valid GID range for users. Users having non-valid GID as primary group ID
18000 aren't allowed to log in. If user belongs to supplementary groups with
18001 non-valid GIDs, those groups are not set.
18002 Defaults to @samp{1}.
18005 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
18007 Defaults to @samp{0}.
18010 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
18011 Maximum allowed length for mail keyword name. It's only forced when
18012 trying to create new keywords.
18013 Defaults to @samp{50}.
18016 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
18017 List of directories under which chrooting is allowed for mail
18018 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
18019 too). This setting doesn't affect @samp{login-chroot}
18020 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
18021 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
18022 which local users can modify, that may lead to root exploit. Usually
18023 this should be done only if you don't allow shell access for users.
18024 <doc/wiki/Chrooting.txt>.
18025 Defaults to @samp{()}.
18028 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
18029 Default chroot directory for mail processes. This can be overridden
18030 for specific users in user database by giving @samp{/./} in user's home
18031 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
18032 there is no real need to do chrooting, Dovecot doesn't allow users to
18033 access files outside their mail directory anyway. If your home
18034 directories are prefixed with the chroot directory, append @samp{/.} to
18035 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
18036 Defaults to @samp{""}.
18039 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
18040 UNIX socket path to master authentication server to find users.
18041 This is used by imap (for shared users) and lda.
18042 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
18045 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
18046 Directory where to look up mail plugins.
18047 Defaults to @samp{"/usr/lib/dovecot"}.
18050 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
18051 List of plugins to load for all services. Plugins specific to IMAP,
18052 LDA, etc.@: are added to this list in their own .conf files.
18053 Defaults to @samp{()}.
18056 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
18057 The minimum number of mails in a mailbox before updates are done to
18058 cache file. This allows optimizing Dovecot's behavior to do less disk
18059 writes at the cost of more disk reads.
18060 Defaults to @samp{0}.
18063 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
18064 When IDLE command is running, mailbox is checked once in a while to
18065 see if there are any new mails or other changes. This setting defines
18066 the minimum time to wait between those checks. Dovecot can also use
18067 dnotify, inotify and kqueue to find out immediately when changes
18069 Defaults to @samp{"30 secs"}.
18072 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
18073 Save mails with CR+LF instead of plain LF. This makes sending those
18074 mails take less CPU, especially with sendfile() syscall with Linux and
18075 FreeBSD. But it also creates a bit more disk I/O which may just make it
18076 slower. Also note that if other software reads the mboxes/maildirs,
18077 they may handle the extra CRs wrong and cause problems.
18078 Defaults to @samp{#f}.
18081 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
18082 By default LIST command returns all entries in maildir beginning
18083 with a dot. Enabling this option makes Dovecot return only entries
18084 which are directories. This is done by stat()ing each entry, so it
18085 causes more disk I/O.
18086 (For systems setting struct @samp{dirent->d_type} this check is free
18087 and it's done always regardless of this setting).
18088 Defaults to @samp{#f}.
18091 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
18092 When copying a message, do it with hard links whenever possible.
18093 This makes the performance much better, and it's unlikely to have any
18095 Defaults to @samp{#t}.
18098 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
18099 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
18100 directory only when its mtime changes unexpectedly or when we can't find
18101 the mail otherwise.
18102 Defaults to @samp{#f}.
18105 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
18106 Which locking methods to use for locking mbox. There are four
18111 Create <mailbox>.lock file. This is the oldest and most NFS-safe
18112 solution. If you want to use /var/mail/ like directory, the users will
18113 need write access to that directory.
18115 Same as dotlock, but if it fails because of permissions or because there
18116 isn't enough disk space, just skip it.
18118 Use this if possible. Works with NFS too if lockd is used.
18120 May not exist in all systems. Doesn't work with NFS.
18122 May not exist in all systems. Doesn't work with NFS.
18125 You can use multiple locking methods; if you do the order they're declared
18126 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
18127 locking methods as well. Some operating systems don't allow using some of
18128 them simultaneously.
18131 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
18135 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
18136 Maximum time to wait for lock (all of them) before aborting.
18137 Defaults to @samp{"5 mins"}.
18140 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
18141 If dotlock exists but the mailbox isn't modified in any way,
18142 override the lock file after this much time.
18143 Defaults to @samp{"2 mins"}.
18146 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
18147 When mbox changes unexpectedly we have to fully read it to find out
18148 what changed. If the mbox is large this can take a long time. Since
18149 the change is usually just a newly appended mail, it'd be faster to
18150 simply read the new mails. If this setting is enabled, Dovecot does
18151 this but still safely fallbacks to re-reading the whole mbox file
18152 whenever something in mbox isn't how it's expected to be. The only real
18153 downside to this setting is that if some other MUA changes message
18154 flags, Dovecot doesn't notice it immediately. Note that a full sync is
18155 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
18156 Defaults to @samp{#t}.
18159 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
18160 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
18161 EXAMINE, EXPUNGE or CHECK commands. If this is set,
18162 @samp{mbox-dirty-syncs} is ignored.
18163 Defaults to @samp{#f}.
18166 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
18167 Delay writing mbox headers until doing a full write sync (EXPUNGE
18168 and CHECK commands and when closing the mailbox). This is especially
18169 useful for POP3 where clients often delete all mails. The downside is
18170 that our changes aren't immediately visible to other MUAs.
18171 Defaults to @samp{#t}.
18174 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
18175 If mbox size is smaller than this (e.g.@: 100k), don't write index
18176 files. If an index file already exists it's still read, just not
18178 Defaults to @samp{0}.
18181 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
18182 Maximum dbox file size until it's rotated.
18183 Defaults to @samp{10000000}.
18186 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
18187 Maximum dbox file age until it's rotated. Typically in days. Day
18188 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
18190 Defaults to @samp{"1d"}.
18193 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
18194 When creating new mdbox files, immediately preallocate their size to
18195 @samp{mdbox-rotate-size}. This setting currently works only in Linux
18196 with some file systems (ext4, xfs).
18197 Defaults to @samp{#f}.
18200 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
18201 sdbox and mdbox support saving mail attachments to external files,
18202 which also allows single instance storage for them. Other backends
18203 don't support this for now.
18205 WARNING: This feature hasn't been tested much yet. Use at your own risk.
18207 Directory root where to store mail attachments. Disabled, if empty.
18208 Defaults to @samp{""}.
18211 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
18212 Attachments smaller than this aren't saved externally. It's also
18213 possible to write a plugin to disable saving specific attachments
18215 Defaults to @samp{128000}.
18218 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
18219 File system backend to use for saving attachments:
18222 No SiS done by Dovecot (but this might help FS's own deduplication)
18224 SiS with immediate byte-by-byte comparison during saving
18225 @item sis-queue posix
18226 SiS with delayed comparison and deduplication.
18228 Defaults to @samp{"sis posix"}.
18231 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
18232 Hash format to use in attachment filenames. You can add any text and
18233 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
18234 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
18235 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
18236 Defaults to @samp{"%@{sha1@}"}.
18239 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
18241 Defaults to @samp{100}.
18244 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
18246 Defaults to @samp{1000}.
18249 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
18250 Default VSZ (virtual memory size) limit for service processes.
18251 This is mainly intended to catch and kill processes that leak memory
18252 before they eat up everything.
18253 Defaults to @samp{256000000}.
18256 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
18257 Login user is internally used by login processes. This is the most
18258 untrusted user in Dovecot system. It shouldn't have access to anything
18260 Defaults to @samp{"dovenull"}.
18263 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
18264 Internal user is used by unprivileged processes. It should be
18265 separate from login user, so that login processes can't disturb other
18267 Defaults to @samp{"dovecot"}.
18270 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
18271 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
18272 Defaults to @samp{"required"}.
18275 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
18276 PEM encoded X.509 SSL/TLS certificate (public key).
18277 Defaults to @samp{"</etc/dovecot/default.pem"}.
18280 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
18281 PEM encoded SSL/TLS private key. The key is opened before
18282 dropping root privileges, so keep the key file unreadable by anyone but
18284 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
18287 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
18288 If key file is password protected, give the password here.
18289 Alternatively give it when starting dovecot with -p parameter. Since
18290 this file is often world-readable, you may want to place this setting
18291 instead to a different.
18292 Defaults to @samp{""}.
18295 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
18296 PEM encoded trusted certificate authority. Set this only if you
18297 intend to use @samp{ssl-verify-client-cert? #t}. The file should
18298 contain the CA certificate(s) followed by the matching
18299 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
18300 Defaults to @samp{""}.
18303 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
18304 Require that CRL check succeeds for client certificates.
18305 Defaults to @samp{#t}.
18308 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
18309 Request client to send a certificate. If you also want to require
18310 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
18311 Defaults to @samp{#f}.
18314 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
18315 Which field from certificate to use for username. commonName and
18316 x500UniqueIdentifier are the usual choices. You'll also need to set
18317 @samp{auth-ssl-username-from-cert? #t}.
18318 Defaults to @samp{"commonName"}.
18321 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
18322 Minimum SSL protocol version to accept.
18323 Defaults to @samp{"TLSv1"}.
18326 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
18327 SSL ciphers to use.
18328 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
18331 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
18332 SSL crypto device to use, for valid values run "openssl engine".
18333 Defaults to @samp{""}.
18336 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
18337 Address to use when sending rejection mails.
18338 %d expands to recipient domain.
18339 Defaults to @samp{"postmaster@@%d"}.
18342 @deftypevr {@code{dovecot-configuration} parameter} string hostname
18343 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
18344 and in LMTP replies. Default is the system's real hostname@@domain.
18345 Defaults to @samp{""}.
18348 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
18349 If user is over quota, return with temporary failure instead of
18351 Defaults to @samp{#f}.
18354 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
18355 Binary to use for sending mails.
18356 Defaults to @samp{"/usr/sbin/sendmail"}.
18359 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
18360 If non-empty, send mails via this SMTP host[:port] instead of
18362 Defaults to @samp{""}.
18365 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
18366 Subject: header to use for rejection mails. You can use the same
18367 variables as for @samp{rejection-reason} below.
18368 Defaults to @samp{"Rejected: %s"}.
18371 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
18372 Human readable error message for rejection mails. You can use
18385 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
18388 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
18389 Delimiter character between local-part and detail in email
18391 Defaults to @samp{"+"}.
18394 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
18395 Header where the original recipient address (SMTP's RCPT TO:
18396 address) is taken from if not available elsewhere. With dovecot-lda -a
18397 parameter overrides this. A commonly used header for this is
18399 Defaults to @samp{""}.
18402 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
18403 Should saving a mail to a nonexistent mailbox automatically create
18405 Defaults to @samp{#f}.
18408 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
18409 Should automatically created mailboxes be also automatically
18411 Defaults to @samp{#f}.
18414 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
18415 Maximum IMAP command line length. Some clients generate very long
18416 command lines with huge mailboxes, so you may need to raise this if you
18417 get "Too long argument" or "IMAP command line too large" errors
18419 Defaults to @samp{64000}.
18422 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
18423 IMAP logout format string:
18426 total number of bytes read from client
18428 total number of bytes sent to client.
18430 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
18431 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@}"}.
18434 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
18435 Override the IMAP CAPABILITY response. If the value begins with '+',
18436 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
18437 Defaults to @samp{""}.
18440 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
18441 How long to wait between "OK Still here" notifications when client
18443 Defaults to @samp{"2 mins"}.
18446 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
18447 ID field names and values to send to clients. Using * as the value
18448 makes Dovecot use the default value. The following fields have default
18449 values currently: name, version, os, os-version, support-url,
18451 Defaults to @samp{""}.
18454 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
18455 ID fields sent by client to log. * means everything.
18456 Defaults to @samp{""}.
18459 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
18460 Workarounds for various client bugs:
18463 @item delay-newmail
18464 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
18465 CHECK commands. Some clients ignore them otherwise, for example OSX
18466 Mail (<v2.1). Outlook Express breaks more badly though, without this it
18467 may show user "Message no longer in server" errors. Note that OE6
18468 still breaks even with this workaround if synchronization is set to
18471 @item tb-extra-mailbox-sep
18472 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
18473 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
18474 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
18476 @item tb-lsub-flags
18477 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
18478 This makes Thunderbird realize they aren't selectable and show them
18479 greyed out, instead of only later giving "not selectable" popup error.
18481 Defaults to @samp{()}.
18484 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
18485 Host allowed in URLAUTH URLs sent by client. "*" allows all.
18486 Defaults to @samp{""}.
18490 Whew! Lots of configuration options. The nice thing about it though is
18491 that Guix has a complete interface to Dovecot's configuration
18492 language. This allows not only a nice way to declare configurations,
18493 but also offers reflective capabilities as well: users can write code to
18494 inspect and transform configurations from within Scheme.
18496 However, it could be that you just want to get a @code{dovecot.conf} up
18497 and running. In that case, you can pass an
18498 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
18499 @code{dovecot-service}. As its name indicates, an opaque configuration
18500 does not have easy reflective capabilities.
18502 Available @code{opaque-dovecot-configuration} fields are:
18504 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
18505 The dovecot package.
18508 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
18509 The contents of the @code{dovecot.conf}, as a string.
18512 For example, if your @code{dovecot.conf} is just the empty string, you
18513 could instantiate a dovecot service like this:
18516 (dovecot-service #:config
18517 (opaque-dovecot-configuration
18521 @subsubheading OpenSMTPD Service
18523 @deffn {Scheme Variable} opensmtpd-service-type
18524 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
18525 service, whose value should be an @code{opensmtpd-configuration} object
18526 as in this example:
18529 (service opensmtpd-service-type
18530 (opensmtpd-configuration
18531 (config-file (local-file "./my-smtpd.conf"))))
18535 @deftp {Data Type} opensmtpd-configuration
18536 Data type representing the configuration of opensmtpd.
18539 @item @code{package} (default: @var{opensmtpd})
18540 Package object of the OpenSMTPD SMTP server.
18542 @item @code{config-file} (default: @code{%default-opensmtpd-file})
18543 File-like object of the OpenSMTPD configuration file to use. By default
18544 it listens on the loopback network interface, and allows for mail from
18545 users and daemons on the local machine, as well as permitting email to
18546 remote servers. Run @command{man smtpd.conf} for more information.
18551 @subsubheading Exim Service
18553 @cindex mail transfer agent (MTA)
18554 @cindex MTA (mail transfer agent)
18557 @deffn {Scheme Variable} exim-service-type
18558 This is the type of the @uref{https://exim.org, Exim} mail transfer
18559 agent (MTA), whose value should be an @code{exim-configuration} object
18560 as in this example:
18563 (service exim-service-type
18564 (exim-configuration
18565 (config-file (local-file "./my-exim.conf"))))
18569 In order to use an @code{exim-service-type} service you must also have a
18570 @code{mail-aliases-service-type} service present in your
18571 @code{operating-system} (even if it has no aliases).
18573 @deftp {Data Type} exim-configuration
18574 Data type representing the configuration of exim.
18577 @item @code{package} (default: @var{exim})
18578 Package object of the Exim server.
18580 @item @code{config-file} (default: @code{#f})
18581 File-like object of the Exim configuration file to use. If its value is
18582 @code{#f} then use the default configuration file from the package
18583 provided in @code{package}. The resulting configuration file is loaded
18584 after setting the @code{exim_user} and @code{exim_group} configuration
18590 @subsubheading Getmail service
18595 @deffn {Scheme Variable} getmail-service-type
18596 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
18597 mail retriever, whose value should be an @code{getmail-configuration}.
18600 Available @code{getmail-configuration} fields are:
18602 @deftypevr {@code{getmail-configuration} parameter} symbol name
18603 A symbol to identify the getmail service.
18605 Defaults to @samp{"unset"}.
18609 @deftypevr {@code{getmail-configuration} parameter} package package
18610 The getmail package to use.
18614 @deftypevr {@code{getmail-configuration} parameter} string user
18615 The user to run getmail as.
18617 Defaults to @samp{"getmail"}.
18621 @deftypevr {@code{getmail-configuration} parameter} string group
18622 The group to run getmail as.
18624 Defaults to @samp{"getmail"}.
18628 @deftypevr {@code{getmail-configuration} parameter} string directory
18629 The getmail directory to use.
18631 Defaults to @samp{"/var/lib/getmail/default"}.
18635 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
18636 The getmail configuration file to use.
18638 Available @code{getmail-configuration-file} fields are:
18640 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
18641 What mail account to retrieve mail from, and how to access that account.
18643 Available @code{getmail-retriever-configuration} fields are:
18645 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
18646 The type of mail retriever to use. Valid values include @samp{passwd}
18649 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
18653 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
18654 Username to login to the mail server with.
18656 Defaults to @samp{unset}.
18660 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
18661 Username to login to the mail server with.
18663 Defaults to @samp{unset}.
18667 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
18668 Port number to connect to.
18670 Defaults to @samp{#f}.
18674 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
18675 Override fields from passwd.
18677 Defaults to @samp{""}.
18681 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
18682 Override fields from passwd.
18684 Defaults to @samp{()}.
18688 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
18689 PEM-formatted key file to use for the TLS negotiation.
18691 Defaults to @samp{""}.
18695 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
18696 PEM-formatted certificate file to use for the TLS negotiation.
18698 Defaults to @samp{""}.
18702 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
18703 CA certificates to use.
18705 Defaults to @samp{""}.
18709 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
18710 Extra retriever parameters.
18712 Defaults to @samp{()}.
18718 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
18719 What to do with retrieved messages.
18721 Available @code{getmail-destination-configuration} fields are:
18723 @deftypevr {@code{getmail-destination-configuration} parameter} string type
18724 The type of mail destination. Valid values include @samp{Maildir},
18725 @samp{Mboxrd} and @samp{MDA_external}.
18727 Defaults to @samp{unset}.
18731 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
18732 The path option for the mail destination. The behaviour depends on the
18735 Defaults to @samp{""}.
18739 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
18740 Extra destination parameters
18742 Defaults to @samp{()}.
18748 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
18751 Available @code{getmail-options-configuration} fields are:
18753 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
18754 If set to @samp{0}, getmail will only print warnings and errors. A
18755 value of @samp{1} means that messages will be printed about retrieving
18756 and deleting messages. If set to @samp{2}, getmail will print messages
18757 about each of it's actions.
18759 Defaults to @samp{1}.
18763 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
18764 If true, getmail will retrieve all available messages. Otherwise it
18765 will only retrieve messages it hasn't seen previously.
18767 Defaults to @samp{#t}.
18771 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
18772 If set to true, messages will be deleted from the server after
18773 retrieving and successfully delivering them. Otherwise, messages will
18774 be left on the server.
18776 Defaults to @samp{#f}.
18780 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
18781 Getmail will delete messages this number of days after seeing them, if
18782 they have been delivered. This means messages will be left on the
18783 server this number of days after delivering them. A value of @samp{0}
18784 disabled this feature.
18786 Defaults to @samp{0}.
18790 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
18791 Delete messages larger than this of bytes after retrieving them, even if
18792 the delete and delete-after options are disabled. A value of @samp{0}
18793 disables this feature.
18795 Defaults to @samp{0}.
18799 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
18800 Retrieve messages totalling up to this number of bytes before closing
18801 the session with the server. A value of @samp{0} disables this feature.
18803 Defaults to @samp{0}.
18807 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
18808 Don't retrieve messages larger than this number of bytes. A value of
18809 @samp{0} disables this feature.
18811 Defaults to @samp{0}.
18815 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
18816 If true, getmail will add a Delivered-To header to messages.
18818 Defaults to @samp{#t}.
18822 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
18823 If set, getmail adds a Received header to the messages.
18825 Defaults to @samp{#t}.
18829 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
18830 Getmail will record a log of its actions to the named file. A value of
18831 @samp{""} disables this feature.
18833 Defaults to @samp{""}.
18837 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
18838 If true, getmail will record a log of its actions using the system
18841 Defaults to @samp{#f}.
18845 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
18846 If true, getmail will log information about messages not retrieved and
18847 the reason for not retrieving them, as well as starting and ending
18850 Defaults to @samp{#f}.
18854 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
18855 Extra options to include.
18857 Defaults to @samp{()}.
18865 @deftypevr {@code{getmail-configuration} parameter} list idle
18866 A list of mailboxes that getmail should wait on the server for new mail
18867 notifications. This depends on the server supporting the IDLE
18870 Defaults to @samp{()}.
18874 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
18875 Environment variables to set for getmail.
18877 Defaults to @samp{()}.
18881 @subsubheading Mail Aliases Service
18883 @cindex email aliases
18884 @cindex aliases, for email addresses
18886 @deffn {Scheme Variable} mail-aliases-service-type
18887 This is the type of the service which provides @code{/etc/aliases},
18888 specifying how to deliver mail to users on this system.
18891 (service mail-aliases-service-type
18892 '(("postmaster" "bob")
18893 ("bob" "bob@@example.com" "bob@@example2.com")))
18897 The configuration for a @code{mail-aliases-service-type} service is an
18898 association list denoting how to deliver mail that comes to this
18899 system. Each entry is of the form @code{(alias addresses ...)}, with
18900 @code{alias} specifying the local alias and @code{addresses} specifying
18901 where to deliver this user's mail.
18903 The aliases aren't required to exist as users on the local system. In
18904 the above example, there doesn't need to be a @code{postmaster} entry in
18905 the @code{operating-system}'s @code{user-accounts} in order to deliver
18906 the @code{postmaster} mail to @code{bob} (which subsequently would
18907 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
18909 @subsubheading GNU Mailutils IMAP4 Daemon
18910 @cindex GNU Mailutils IMAP4 Daemon
18912 @deffn {Scheme Variable} imap4d-service-type
18913 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
18914 mailutils, GNU Mailutils Manual}), whose value should be an
18915 @code{imap4d-configuration} object as in this example:
18918 (service imap4d-service-type
18919 (imap4d-configuration
18920 (config-file (local-file "imap4d.conf"))))
18924 @deftp {Data Type} imap4d-configuration
18925 Data type representing the configuration of @command{imap4d}.
18928 @item @code{package} (default: @code{mailutils})
18929 The package that provides @command{imap4d}.
18931 @item @code{config-file} (default: @code{%default-imap4d-config-file})
18932 File-like object of the configuration file to use, by default it will listen
18933 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
18934 Mailutils Manual}, for details.
18939 @node Messaging Services
18940 @subsection Messaging Services
18945 The @code{(gnu services messaging)} module provides Guix service
18946 definitions for messaging services: currently only Prosody is supported.
18948 @subsubheading Prosody Service
18950 @deffn {Scheme Variable} prosody-service-type
18951 This is the type for the @uref{https://prosody.im, Prosody XMPP
18952 communication server}. Its value must be a @code{prosody-configuration}
18953 record as in this example:
18956 (service prosody-service-type
18957 (prosody-configuration
18958 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
18961 (int-component-configuration
18962 (hostname "conference.example.net")
18964 (mod-muc (mod-muc-configuration)))))
18967 (virtualhost-configuration
18968 (domain "example.net"))))))
18971 See below for details about @code{prosody-configuration}.
18975 By default, Prosody does not need much configuration. Only one
18976 @code{virtualhosts} field is needed: it specifies the domain you wish
18979 You can perform various sanity checks on the generated configuration
18980 with the @code{prosodyctl check} command.
18982 Prosodyctl will also help you to import certificates from the
18983 @code{letsencrypt} directory so that the @code{prosody} user can access
18984 them. See @url{https://prosody.im/doc/letsencrypt}.
18987 prosodyctl --root cert import /etc/letsencrypt/live
18990 The available configuration parameters follow. Each parameter
18991 definition is preceded by its type; for example, @samp{string-list foo}
18992 indicates that the @code{foo} parameter should be specified as a list of
18993 strings. Types starting with @code{maybe-} denote parameters that won't
18994 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
18996 There is also a way to specify the configuration as a string, if you
18997 have an old @code{prosody.cfg.lua} file that you want to port over from
18998 some other system; see the end for more details.
19000 The @code{file-object} type designates either a file-like object
19001 (@pxref{G-Expressions, file-like objects}) or a file name.
19003 @c The following documentation was initially generated by
19004 @c (generate-documentation) in (gnu services messaging). Manually maintained
19005 @c documentation is better, so we shouldn't hesitate to edit below as
19006 @c needed. However if the change you want to make to this documentation
19007 @c can be done in an automated way, it's probably easier to change
19008 @c (generate-documentation) than to make it below and have to deal with
19009 @c the churn as Prosody updates.
19011 Available @code{prosody-configuration} fields are:
19013 @deftypevr {@code{prosody-configuration} parameter} package prosody
19014 The Prosody package.
19017 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
19018 Location of the Prosody data storage directory. See
19019 @url{https://prosody.im/doc/configure}.
19020 Defaults to @samp{"/var/lib/prosody"}.
19023 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
19024 Additional plugin directories. They are searched in all the specified
19025 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
19026 Defaults to @samp{()}.
19029 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
19030 Every virtual host and component needs a certificate so that clients and
19031 servers can securely verify its identity. Prosody will automatically load
19032 certificates/keys from the directory specified here.
19033 Defaults to @samp{"/etc/prosody/certs"}.
19036 @deftypevr {@code{prosody-configuration} parameter} string-list admins
19037 This is a list of accounts that are admins for the server. Note that you
19038 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
19039 @url{https://prosody.im/doc/creating_accounts}.
19040 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
19041 Defaults to @samp{()}.
19044 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
19045 Enable use of libevent for better performance under high load. See
19046 @url{https://prosody.im/doc/libevent}.
19047 Defaults to @samp{#f}.
19050 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
19051 This is the list of modules Prosody will load on startup. It looks for
19052 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
19053 Documentation on modules can be found at:
19054 @url{https://prosody.im/doc/modules}.
19055 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
19058 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
19059 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
19060 should you want to disable them then add them to this list.
19061 Defaults to @samp{()}.
19064 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
19065 Path to a text file where the shared groups are defined. If this path is
19066 empty then @samp{mod_groups} does nothing. See
19067 @url{https://prosody.im/doc/modules/mod_groups}.
19068 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
19071 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
19072 Disable account creation by default, for security. See
19073 @url{https://prosody.im/doc/creating_accounts}.
19074 Defaults to @samp{#f}.
19077 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
19078 These are the SSL/TLS-related settings. Most of them are disabled so to
19079 use Prosody's defaults. If you do not completely understand these options, do
19080 not add them to your config, it is easy to lower the security of your server
19081 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
19083 Available @code{ssl-configuration} fields are:
19085 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
19086 This determines what handshake to use.
19089 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
19090 Path to your private key file.
19093 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
19094 Path to your certificate file.
19097 @deftypevr {@code{ssl-configuration} parameter} file-object capath
19098 Path to directory containing root certificates that you wish Prosody to
19099 trust when verifying the certificates of remote servers.
19100 Defaults to @samp{"/etc/ssl/certs"}.
19103 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
19104 Path to a file containing root certificates that you wish Prosody to trust.
19105 Similar to @code{capath} but with all certificates concatenated together.
19108 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
19109 A list of verification options (these mostly map to OpenSSL's
19110 @code{set_verify()} flags).
19113 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
19114 A list of general options relating to SSL/TLS. These map to OpenSSL's
19115 @code{set_options()}. For a full list of options available in LuaSec, see the
19119 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
19120 How long a chain of certificate authorities to check when looking for a
19121 trusted root certificate.
19124 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
19125 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
19126 clients, and in what order.
19129 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
19130 A path to a file containing parameters for Diffie-Hellman key exchange. You
19131 can create such a file with:
19132 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
19135 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
19136 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
19137 @samp{"secp384r1"}.
19140 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
19141 A list of ``extra'' verification options.
19144 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
19145 Password for encrypted private keys.
19150 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
19151 Whether to force all client-to-server connections to be encrypted or not.
19152 See @url{https://prosody.im/doc/modules/mod_tls}.
19153 Defaults to @samp{#f}.
19156 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
19157 Set of mechanisms that will never be offered. See
19158 @url{https://prosody.im/doc/modules/mod_saslauth}.
19159 Defaults to @samp{("DIGEST-MD5")}.
19162 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
19163 Whether to force all server-to-server connections to be encrypted or not.
19164 See @url{https://prosody.im/doc/modules/mod_tls}.
19165 Defaults to @samp{#f}.
19168 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
19169 Whether to require encryption and certificate authentication. This
19170 provides ideal security, but requires servers you communicate with to support
19171 encryption AND present valid, trusted certificates. See
19172 @url{https://prosody.im/doc/s2s#security}.
19173 Defaults to @samp{#f}.
19176 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
19177 Many servers don't support encryption or have invalid or self-signed
19178 certificates. You can list domains here that will not be required to
19179 authenticate using certificates. They will be authenticated using DNS. See
19180 @url{https://prosody.im/doc/s2s#security}.
19181 Defaults to @samp{()}.
19184 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
19185 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
19186 valid certificates for some domains by specifying a list here. See
19187 @url{https://prosody.im/doc/s2s#security}.
19188 Defaults to @samp{()}.
19191 @deftypevr {@code{prosody-configuration} parameter} string authentication
19192 Select the authentication backend to use. The default provider stores
19193 passwords in plaintext and uses Prosody's configured data storage to store the
19194 authentication data. If you do not trust your server please see
19195 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
19196 about using the hashed backend. See also
19197 @url{https://prosody.im/doc/authentication}
19198 Defaults to @samp{"internal_plain"}.
19201 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
19202 Set logging options. Advanced logging configuration is not yet supported
19203 by the Prosody service. See @url{https://prosody.im/doc/logging}.
19204 Defaults to @samp{"*syslog"}.
19207 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
19208 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
19209 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
19212 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
19213 Maximum allowed size of the HTTP body (in bytes).
19216 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
19217 Some modules expose their own URL in various ways. This URL is built
19218 from the protocol, host and port used. If Prosody sits behind a proxy, the
19219 public URL will be @code{http-external-url} instead. See
19220 @url{https://prosody.im/doc/http#external_url}.
19223 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
19224 A host in Prosody is a domain on which user accounts can be created. For
19225 example if you want your users to have addresses like
19226 @samp{"john.smith@@example.com"} then you need to add a host
19227 @samp{"example.com"}. All options in this list will apply only to this host.
19229 Note: the name @emph{virtual} host is used in configuration to avoid confusion with
19230 the actual physical host that Prosody is installed on. A single Prosody
19231 instance can serve many domains, each one defined as a VirtualHost entry in
19232 Prosody's configuration. Conversely a server that hosts a single domain would
19233 have just one VirtualHost entry.
19235 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
19237 Available @code{virtualhost-configuration} fields are:
19239 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:
19240 @deftypevr {@code{virtualhost-configuration} parameter} string domain
19241 Domain you wish Prosody to serve.
19246 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
19247 Components are extra services on a server which are available to clients,
19248 usually on a subdomain of the main server (such as
19249 @samp{"mycomponent.example.com"}). Example components might be chatroom
19250 servers, user directories, or gateways to other protocols.
19252 Internal components are implemented with Prosody-specific plugins. To add an
19253 internal component, you simply fill the hostname field, and the plugin you wish
19254 to use for the component.
19256 See @url{https://prosody.im/doc/components}.
19257 Defaults to @samp{()}.
19259 Available @code{int-component-configuration} fields are:
19261 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:
19262 @deftypevr {@code{int-component-configuration} parameter} string hostname
19263 Hostname of the component.
19266 @deftypevr {@code{int-component-configuration} parameter} string plugin
19267 Plugin you wish to use for the component.
19270 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
19271 Multi-user chat (MUC) is Prosody's module for allowing you to create
19272 hosted chatrooms/conferences for XMPP users.
19274 General information on setting up and using multi-user chatrooms can be found
19275 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
19276 which you should read if you are new to XMPP chatrooms.
19278 See also @url{https://prosody.im/doc/modules/mod_muc}.
19280 Available @code{mod-muc-configuration} fields are:
19282 @deftypevr {@code{mod-muc-configuration} parameter} string name
19283 The name to return in service discovery responses.
19284 Defaults to @samp{"Prosody Chatrooms"}.
19287 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
19288 If @samp{#t}, this will only allow admins to create new chatrooms.
19289 Otherwise anyone can create a room. The value @samp{"local"} restricts room
19290 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
19291 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
19292 restricts to service administrators only.
19293 Defaults to @samp{#f}.
19296 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
19297 Maximum number of history messages that will be sent to the member that has
19298 just joined the room.
19299 Defaults to @samp{20}.
19306 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
19307 External components use XEP-0114, which most standalone components
19308 support. To add an external component, you simply fill the hostname field. See
19309 @url{https://prosody.im/doc/components}.
19310 Defaults to @samp{()}.
19312 Available @code{ext-component-configuration} fields are:
19314 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:
19315 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
19316 Password which the component will use to log in.
19319 @deftypevr {@code{ext-component-configuration} parameter} string hostname
19320 Hostname of the component.
19325 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
19326 Port(s) Prosody listens on for component connections.
19327 Defaults to @samp{(5347)}.
19330 @deftypevr {@code{prosody-configuration} parameter} string component-interface
19331 Interface Prosody listens on for component connections.
19332 Defaults to @samp{"127.0.0.1"}.
19335 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
19336 Raw content that will be added to the configuration file.
19339 It could be that you just want to get a @code{prosody.cfg.lua}
19340 up and running. In that case, you can pass an
19341 @code{opaque-prosody-configuration} record as the value of
19342 @code{prosody-service-type}. As its name indicates, an opaque configuration
19343 does not have easy reflective capabilities.
19344 Available @code{opaque-prosody-configuration} fields are:
19346 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
19347 The prosody package.
19350 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
19351 The contents of the @code{prosody.cfg.lua} to use.
19354 For example, if your @code{prosody.cfg.lua} is just the empty
19355 string, you could instantiate a prosody service like this:
19358 (service prosody-service-type
19359 (opaque-prosody-configuration
19360 (prosody.cfg.lua "")))
19363 @c end of Prosody auto-generated documentation
19365 @subsubheading BitlBee Service
19367 @cindex IRC (Internet Relay Chat)
19368 @cindex IRC gateway
19369 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
19370 interface to a variety of messaging protocols such as XMPP.
19372 @defvr {Scheme Variable} bitlbee-service-type
19373 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
19374 gateway daemon. Its value is a @code{bitlbee-configuration} (see
19377 To have BitlBee listen on port 6667 on localhost, add this line to your
19381 (service bitlbee-service-type)
19385 @deftp {Data Type} bitlbee-configuration
19386 This is the configuration for BitlBee, with the following fields:
19389 @item @code{interface} (default: @code{"127.0.0.1"})
19390 @itemx @code{port} (default: @code{6667})
19391 Listen on the network interface corresponding to the IP address
19392 specified in @var{interface}, on @var{port}.
19394 When @var{interface} is @code{127.0.0.1}, only local clients can
19395 connect; when it is @code{0.0.0.0}, connections can come from any
19396 networking interface.
19398 @item @code{bitlbee} (default: @code{bitlbee})
19399 The BitlBee package to use.
19401 @item @code{plugins} (default: @code{'()})
19402 List of plugin packages to use---e.g., @code{bitlbee-discord}.
19404 @item @code{extra-settings} (default: @code{""})
19405 Configuration snippet added as-is to the BitlBee configuration file.
19409 @subsubheading Quassel Service
19411 @cindex IRC (Internet Relay Chat)
19412 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
19413 meaning that one or more clients can attach to and detach from the
19416 @defvr {Scheme Variable} quassel-service-type
19417 This is the service type for the @url{https://quassel-irc.org/,Quassel}
19418 IRC backend daemon. Its value is a @code{quassel-configuration}
19422 @deftp {Data Type} quassel-configuration
19423 This is the configuration for Quassel, with the following fields:
19426 @item @code{quassel} (default: @code{quassel})
19427 The Quassel package to use.
19429 @item @code{interface} (default: @code{"::,0.0.0.0"})
19430 @item @code{port} (default: @code{4242})
19431 Listen on the network interface(s) corresponding to the IPv4 or IPv6
19432 interfaces specified in the comma delimited @var{interface}, on
19435 @item @code{loglevel} (default: @code{"Info"})
19436 The level of logging desired. Accepted values are Debug, Info, Warning
19441 @node Telephony Services
19442 @subsection Telephony Services
19444 @cindex Murmur (VoIP server)
19445 @cindex VoIP server
19446 This section describes how to set up and run a Murmur server. Murmur is
19447 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
19450 @deftp {Data Type} murmur-configuration
19451 The service type for the Murmur server. An example configuration can
19455 (service murmur-service-type
19456 (murmur-configuration
19458 "Welcome to this Mumble server running on Guix!")
19459 (cert-required? #t) ;disallow text password logins
19460 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
19461 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
19464 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
19465 password with the command that is printed during the activation phase.
19467 It is recommended to register a normal Mumble user account
19468 and grant it admin or moderator rights.
19469 You can use the @code{mumble} client to
19470 login as new normal user, register yourself, and log out.
19471 For the next step login with the name @code{SuperUser} use
19472 the @code{SuperUser} password that you set previously,
19473 and grant your newly registered mumble user administrator or moderator
19474 rights and create some channels.
19476 Available @code{murmur-configuration} fields are:
19479 @item @code{package} (default: @code{mumble})
19480 Package that contains @code{bin/murmurd}.
19482 @item @code{user} (default: @code{"murmur"})
19483 User who will run the Murmur server.
19485 @item @code{group} (default: @code{"murmur"})
19486 Group of the user who will run the murmur server.
19488 @item @code{port} (default: @code{64738})
19489 Port on which the server will listen.
19491 @item @code{welcome-text} (default: @code{""})
19492 Welcome text sent to clients when they connect.
19494 @item @code{server-password} (default: @code{""})
19495 Password the clients have to enter in order to connect.
19497 @item @code{max-users} (default: @code{100})
19498 Maximum of users that can be connected to the server at once.
19500 @item @code{max-user-bandwidth} (default: @code{#f})
19501 Maximum voice traffic a user can send per second.
19503 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
19504 File name of the sqlite database.
19505 The service's user will become the owner of the directory.
19507 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
19508 File name of the log file.
19509 The service's user will become the owner of the directory.
19511 @item @code{autoban-attempts} (default: @code{10})
19512 Maximum number of logins a user can make in @code{autoban-timeframe}
19513 without getting auto banned for @code{autoban-time}.
19515 @item @code{autoban-timeframe} (default: @code{120})
19516 Timeframe for autoban in seconds.
19518 @item @code{autoban-time} (default: @code{300})
19519 Amount of time in seconds for which a client gets banned
19520 when violating the autoban limits.
19522 @item @code{opus-threshold} (default: @code{100})
19523 Percentage of clients that need to support opus
19524 before switching over to opus audio codec.
19526 @item @code{channel-nesting-limit} (default: @code{10})
19527 How deep channels can be nested at maximum.
19529 @item @code{channelname-regex} (default: @code{#f})
19530 A string in form of a Qt regular expression that channel names must conform to.
19532 @item @code{username-regex} (default: @code{#f})
19533 A string in form of a Qt regular expression that user names must conform to.
19535 @item @code{text-message-length} (default: @code{5000})
19536 Maximum size in bytes that a user can send in one text chat message.
19538 @item @code{image-message-length} (default: @code{(* 128 1024)})
19539 Maximum size in bytes that a user can send in one image message.
19541 @item @code{cert-required?} (default: @code{#f})
19542 If it is set to @code{#t} clients that use weak password authentication
19543 will not be accepted. Users must have completed the certificate wizard to join.
19545 @item @code{remember-channel?} (default: @code{#f})
19546 Should murmur remember the last channel each user was in when they disconnected
19547 and put them into the remembered channel when they rejoin.
19549 @item @code{allow-html?} (default: @code{#f})
19550 Should html be allowed in text messages, user comments, and channel descriptions.
19552 @item @code{allow-ping?} (default: @code{#f})
19553 Setting to true exposes the current user count, the maximum user count, and
19554 the server's maximum bandwidth per client to unauthenticated users. In the
19555 Mumble client, this information is shown in the Connect dialog.
19557 Disabling this setting will prevent public listing of the server.
19559 @item @code{bonjour?} (default: @code{#f})
19560 Should the server advertise itself in the local network through the bonjour protocol.
19562 @item @code{send-version?} (default: @code{#f})
19563 Should the murmur server version be exposed in ping requests.
19565 @item @code{log-days} (default: @code{31})
19566 Murmur also stores logs in the database, which are accessible via RPC.
19567 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
19568 or -1 to disable logging to the database.
19570 @item @code{obfuscate-ips?} (default: @code{#t})
19571 Should logged ips be obfuscated to protect the privacy of users.
19573 @item @code{ssl-cert} (default: @code{#f})
19574 File name of the SSL/TLS certificate used for encrypted connections.
19577 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
19579 @item @code{ssl-key} (default: @code{#f})
19580 Filepath to the ssl private key used for encrypted connections.
19582 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
19585 @item @code{ssl-dh-params} (default: @code{#f})
19586 File name of a PEM-encoded file with Diffie-Hellman parameters
19587 for the SSL/TLS encryption. Alternatively you set it to
19588 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
19589 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
19591 @item @code{ssl-ciphers} (default: @code{#f})
19592 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
19595 This option is specified using
19596 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
19597 OpenSSL cipher list notation}.
19599 It is recommended that you try your cipher string using 'openssl ciphers <string>'
19600 before setting it here, to get a feel for which cipher suites you will get.
19601 After setting this option, it is recommend that you inspect your Murmur log
19602 to ensure that Murmur is using the cipher suites that you expected it to.
19604 Note: Changing this option may impact the backwards compatibility of your
19605 Murmur server, and can remove the ability for older Mumble clients to be able
19608 @item @code{public-registration} (default: @code{#f})
19609 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
19611 You can optionally register your server in the public server list that the
19612 @code{mumble} client shows on startup.
19613 You cannot register your server if you have set a @code{server-password},
19614 or set @code{allow-ping} to @code{#f}.
19616 It might take a few hours until it shows up in the public list.
19618 @item @code{file} (default: @code{#f})
19619 Optional alternative override for this configuration.
19623 @deftp {Data Type} murmur-public-registration-configuration
19624 Configuration for public registration of a murmur service.
19628 This is a display name for your server. Not to be confused with the hostname.
19630 @item @code{password}
19631 A password to identify your registration.
19632 Subsequent updates will need the same password. Don't lose your password.
19635 This should be a @code{http://} or @code{https://} link to your web
19638 @item @code{hostname} (default: @code{#f})
19639 By default your server will be listed by its IP address.
19640 If it is set your server will be linked by this host name instead.
19646 @node Monitoring Services
19647 @subsection Monitoring Services
19649 @subsubheading Tailon Service
19651 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
19652 viewing and searching log files.
19654 The following example will configure the service with default values.
19655 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
19658 (service tailon-service-type)
19661 The following example customises more of the Tailon configuration,
19662 adding @command{sed} to the list of allowed commands.
19665 (service tailon-service-type
19666 (tailon-configuration
19668 (tailon-configuration-file
19669 (allowed-commands '("tail" "grep" "awk" "sed"))))))
19673 @deftp {Data Type} tailon-configuration
19674 Data type representing the configuration of Tailon.
19675 This type has the following parameters:
19678 @item @code{config-file} (default: @code{(tailon-configuration-file)})
19679 The configuration file to use for Tailon. This can be set to a
19680 @dfn{tailon-configuration-file} record value, or any gexp
19681 (@pxref{G-Expressions}).
19683 For example, to instead use a local file, the @code{local-file} function
19687 (service tailon-service-type
19688 (tailon-configuration
19689 (config-file (local-file "./my-tailon.conf"))))
19692 @item @code{package} (default: @code{tailon})
19693 The tailon package to use.
19698 @deftp {Data Type} tailon-configuration-file
19699 Data type representing the configuration options for Tailon.
19700 This type has the following parameters:
19703 @item @code{files} (default: @code{(list "/var/log")})
19704 List of files to display. The list can include strings for a single file
19705 or directory, or a list, where the first item is the name of a
19706 subsection, and the remaining items are the files or directories in that
19709 @item @code{bind} (default: @code{"localhost:8080"})
19710 Address and port to which Tailon should bind on.
19712 @item @code{relative-root} (default: @code{#f})
19713 URL path to use for Tailon, set to @code{#f} to not use a path.
19715 @item @code{allow-transfers?} (default: @code{#t})
19716 Allow downloading the log files in the web interface.
19718 @item @code{follow-names?} (default: @code{#t})
19719 Allow tailing of not-yet existent files.
19721 @item @code{tail-lines} (default: @code{200})
19722 Number of lines to read initially from each file.
19724 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
19725 Commands to allow running. By default, @code{sed} is disabled.
19727 @item @code{debug?} (default: @code{#f})
19728 Set @code{debug?} to @code{#t} to show debug messages.
19730 @item @code{wrap-lines} (default: @code{#t})
19731 Initial line wrapping state in the web interface. Set to @code{#t} to
19732 initially wrap lines (the default), or to @code{#f} to initially not
19735 @item @code{http-auth} (default: @code{#f})
19736 HTTP authentication type to use. Set to @code{#f} to disable
19737 authentication (the default). Supported values are @code{"digest"} or
19740 @item @code{users} (default: @code{#f})
19741 If HTTP authentication is enabled (see @code{http-auth}), access will be
19742 restricted to the credentials provided here. To configure users, use a
19743 list of pairs, where the first element of the pair is the username, and
19744 the 2nd element of the pair is the password.
19747 (tailon-configuration-file
19748 (http-auth "basic")
19749 (users '(("user1" . "password1")
19750 ("user2" . "password2"))))
19757 @subsubheading Darkstat Service
19759 Darkstat is a packet sniffer that captures network traffic, calculates
19760 statistics about usage, and serves reports over HTTP.
19762 @defvar {Scheme Variable} darkstat-service-type
19763 This is the service type for the
19764 @uref{https://unix4lyfe.org/darkstat/, darkstat}
19765 service, its value must be a @code{darkstat-configuration} record as in
19769 (service darkstat-service-type
19770 (darkstat-configuration
19771 (interface "eno1")))
19775 @deftp {Data Type} darkstat-configuration
19776 Data type representing the configuration of @command{darkstat}.
19779 @item @code{package} (default: @code{darkstat})
19780 The darkstat package to use.
19782 @item @code{interface}
19783 Capture traffic on the specified network interface.
19785 @item @code{port} (default: @code{"667"})
19786 Bind the web interface to the specified port.
19788 @item @code{bind-address} (default: @code{"127.0.0.1"})
19789 Bind the web interface to the specified address.
19791 @item @code{base} (default: @code{"/"})
19792 Specify the path of the base URL. This can be useful if
19793 @command{darkstat} is accessed via a reverse proxy.
19798 @subsubheading Prometheus Node Exporter Service
19800 @cindex prometheus-node-exporter
19801 The Prometheus ``node exporter'' makes hardware and operating system statistics
19802 provided by the Linux kernel available for the Prometheus monitoring system.
19803 This service should be deployed on all physical nodes and virtual machines,
19804 where monitoring these statistics is desirable.
19806 @defvar {Scheme variable} prometheus-node-exporter-service-type
19807 This is the service type for the
19808 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
19809 service, its value must be a @code{prometheus-node-exporter-configuration}
19810 record as in this example:
19813 (service prometheus-node-exporter-service-type
19814 (prometheus-node-exporter-configuration
19815 (web-listen-address ":9100")))
19819 @deftp {Data Type} prometheus-node-exporter-configuration
19820 Data type representing the configuration of @command{node_exporter}.
19823 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
19824 The prometheus-node-exporter package to use.
19826 @item @code{web-listen-address} (default: @code{":9100"})
19827 Bind the web interface to the specified address.
19832 @subsubheading Zabbix server
19833 @cindex zabbix zabbix-server
19834 Zabbix provides monitoring metrics, among others network utilization, CPU load
19835 and disk space consumption:
19838 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
19839 @item Auto-discovery of servers and network devices and interfaces.
19840 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
19841 @item Distributed monitoring with centralized web administration.
19842 @item Native high performance agents.
19843 @item SLA, and ITIL KPI metrics on reporting.
19844 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
19845 @item Remote command execution through Zabbix proxies.
19848 @c %start of fragment
19850 Available @code{zabbix-server-configuration} fields are:
19852 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
19853 The zabbix-server package.
19857 @deftypevr {@code{zabbix-server-configuration} parameter} string user
19858 User who will run the Zabbix server.
19860 Defaults to @samp{"zabbix"}.
19864 @deftypevr {@code{zabbix-server-configuration} parameter} group group
19865 Group who will run the Zabbix server.
19867 Defaults to @samp{"zabbix"}.
19871 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
19872 Database host name.
19874 Defaults to @samp{"127.0.0.1"}.
19878 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
19881 Defaults to @samp{"zabbix"}.
19885 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
19888 Defaults to @samp{"zabbix"}.
19892 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
19893 Database password. Please, use @code{include-files} with
19894 @code{DBPassword=SECRET} inside a specified file instead.
19896 Defaults to @samp{""}.
19900 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
19903 Defaults to @samp{5432}.
19907 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
19908 Specifies where log messages are written to:
19912 @code{system} - syslog.
19915 @code{file} - file specified with @code{log-file} parameter.
19918 @code{console} - standard output.
19922 Defaults to @samp{""}.
19926 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
19927 Log file name for @code{log-type} @code{file} parameter.
19929 Defaults to @samp{"/var/log/zabbix/server.log"}.
19933 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
19936 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
19940 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
19941 The location of certificate authority (CA) files for SSL server
19942 certificate verification.
19944 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
19948 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
19949 Location of SSL client certificates.
19951 Defaults to @samp{"/etc/ssl/certs"}.
19955 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
19956 Extra options will be appended to Zabbix server configuration file.
19958 Defaults to @samp{""}.
19962 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
19963 You may include individual files or all files in a directory in the
19964 configuration file.
19966 Defaults to @samp{()}.
19970 @c %end of fragment
19972 @subsubheading Zabbix agent
19973 @cindex zabbix zabbix-agent
19975 Zabbix agent gathers information for Zabbix server.
19977 @c %start of fragment
19979 Available @code{zabbix-agent-configuration} fields are:
19981 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
19982 The zabbix-agent package.
19986 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
19987 User who will run the Zabbix agent.
19989 Defaults to @samp{"zabbix"}.
19993 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
19994 Group who will run the Zabbix agent.
19996 Defaults to @samp{"zabbix"}.
20000 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
20001 Unique, case sensitive hostname which is required for active checks and
20002 must match hostname as configured on the server.
20004 Defaults to @samp{"Zabbix server"}.
20008 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
20009 Specifies where log messages are written to:
20013 @code{system} - syslog.
20016 @code{file} - file specified with @code{log-file} parameter.
20019 @code{console} - standard output.
20023 Defaults to @samp{""}.
20027 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
20028 Log file name for @code{log-type} @code{file} parameter.
20030 Defaults to @samp{"/var/log/zabbix/agent.log"}.
20034 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
20037 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
20041 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
20042 List of IP addresses, optionally in CIDR notation, or hostnames of
20043 Zabbix servers and Zabbix proxies. Incoming connections will be
20044 accepted only from the hosts listed here.
20046 Defaults to @samp{("127.0.0.1")}.
20050 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
20051 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
20052 proxies for active checks. If port is not specified, default port is
20053 used. If this parameter is not specified, active checks are disabled.
20055 Defaults to @samp{("127.0.0.1")}.
20059 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
20060 Extra options will be appended to Zabbix server configuration file.
20062 Defaults to @samp{""}.
20066 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
20067 You may include individual files or all files in a directory in the
20068 configuration file.
20070 Defaults to @samp{()}.
20074 @c %end of fragment
20076 @subsubheading Zabbix front-end
20077 @cindex zabbix zabbix-front-end
20079 This service provides a WEB interface to Zabbix server.
20081 @c %start of fragment
20083 Available @code{zabbix-front-end-configuration} fields are:
20085 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
20086 NGINX configuration.
20090 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
20091 Database host name.
20093 Defaults to @samp{"localhost"}.
20097 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
20100 Defaults to @samp{5432}.
20104 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
20107 Defaults to @samp{"zabbix"}.
20111 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
20114 Defaults to @samp{"zabbix"}.
20118 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
20119 Database password. Please, use @code{db-secret-file} instead.
20121 Defaults to @samp{""}.
20125 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
20126 Secret file which will be appended to @file{zabbix.conf.php} file. This
20127 file contains credentials for use by Zabbix front-end. You are expected
20128 to create it manually.
20130 Defaults to @samp{""}.
20134 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
20135 Zabbix server hostname.
20137 Defaults to @samp{"localhost"}.
20141 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
20142 Zabbix server port.
20144 Defaults to @samp{10051}.
20149 @c %end of fragment
20151 @node Kerberos Services
20152 @subsection Kerberos Services
20155 The @code{(gnu services kerberos)} module provides services relating to
20156 the authentication protocol @dfn{Kerberos}.
20158 @subsubheading Krb5 Service
20160 Programs using a Kerberos client library normally
20161 expect a configuration file in @file{/etc/krb5.conf}.
20162 This service generates such a file from a definition provided in the
20163 operating system declaration.
20164 It does not cause any daemon to be started.
20166 No ``keytab'' files are provided by this service---you must explicitly create them.
20167 This service is known to work with the MIT client library, @code{mit-krb5}.
20168 Other implementations have not been tested.
20170 @defvr {Scheme Variable} krb5-service-type
20171 A service type for Kerberos 5 clients.
20175 Here is an example of its use:
20177 (service krb5-service-type
20178 (krb5-configuration
20179 (default-realm "EXAMPLE.COM")
20180 (allow-weak-crypto? #t)
20183 (name "EXAMPLE.COM")
20184 (admin-server "groucho.example.com")
20185 (kdc "karl.example.com"))
20188 (admin-server "kerb-admin.argrx.edu")
20189 (kdc "keys.argrx.edu"))))))
20193 This example provides a Kerberos@tie{}5 client configuration which:
20195 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
20196 of which have distinct administration servers and key distribution centers;
20197 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
20198 specified by clients;
20199 @item Accepts services which only support encryption types known to be weak.
20202 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
20203 Only the most commonly used ones are described here.
20204 For a full list, and more detailed explanation of each, see the MIT
20205 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
20209 @deftp {Data Type} krb5-realm
20210 @cindex realm, kerberos
20213 This field is a string identifying the name of the realm.
20214 A common convention is to use the fully qualified DNS name of your organization,
20215 converted to upper case.
20217 @item @code{admin-server}
20218 This field is a string identifying the host where the administration server is
20222 This field is a string identifying the key distribution center
20227 @deftp {Data Type} krb5-configuration
20230 @item @code{allow-weak-crypto?} (default: @code{#f})
20231 If this flag is @code{#t} then services which only offer encryption algorithms
20232 known to be weak will be accepted.
20234 @item @code{default-realm} (default: @code{#f})
20235 This field should be a string identifying the default Kerberos
20236 realm for the client.
20237 You should set this field to the name of your Kerberos realm.
20238 If this value is @code{#f}
20239 then a realm must be specified with every Kerberos principal when invoking programs
20240 such as @command{kinit}.
20242 @item @code{realms}
20243 This should be a non-empty list of @code{krb5-realm} objects, which clients may
20245 Normally, one of them will have a @code{name} field matching the @code{default-realm}
20251 @subsubheading PAM krb5 Service
20254 The @code{pam-krb5} service allows for login authentication and password
20255 management via Kerberos.
20256 You will need this service if you want PAM enabled applications to authenticate
20257 users using Kerberos.
20259 @defvr {Scheme Variable} pam-krb5-service-type
20260 A service type for the Kerberos 5 PAM module.
20263 @deftp {Data Type} pam-krb5-configuration
20264 Data type representing the configuration of the Kerberos 5 PAM module.
20265 This type has the following parameters:
20267 @item @code{pam-krb5} (default: @code{pam-krb5})
20268 The pam-krb5 package to use.
20270 @item @code{minimum-uid} (default: @code{1000})
20271 The smallest user ID for which Kerberos authentications should be attempted.
20272 Local accounts with lower values will silently fail to authenticate.
20277 @node LDAP Services
20278 @subsection LDAP Services
20280 @cindex nslcd, LDAP service
20282 The @code{(gnu services authentication)} module provides the
20283 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
20284 server. In addition to configuring the service itself, you may want to add
20285 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
20286 Switch} for detailed information.
20288 Here is a simple operating system declaration with a default configuration of
20289 the @code{nslcd-service-type} and a Name Service Switch configuration that
20290 consults the @code{ldap} name service last:
20293 (use-service-modules authentication)
20294 (use-modules (gnu system nss))
20300 (service nslcd-service-type)
20301 (service dhcp-client-service-type)
20303 (name-service-switch
20304 (let ((services (list (name-service (name "db"))
20305 (name-service (name "files"))
20306 (name-service (name "ldap")))))
20307 (name-service-switch
20308 (inherit %mdns-host-lookup-nss)
20309 (password services)
20312 (netgroup services)
20313 (gshadow services)))))
20316 @c %start of generated documentation for nslcd-configuration
20318 Available @code{nslcd-configuration} fields are:
20320 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
20321 The @code{nss-pam-ldapd} package to use.
20325 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
20326 The number of threads to start that can handle requests and perform LDAP
20327 queries. Each thread opens a separate connection to the LDAP server.
20328 The default is to start 5 threads.
20330 Defaults to @samp{disabled}.
20334 @deftypevr {@code{nslcd-configuration} parameter} string uid
20335 This specifies the user id with which the daemon should be run.
20337 Defaults to @samp{"nslcd"}.
20341 @deftypevr {@code{nslcd-configuration} parameter} string gid
20342 This specifies the group id with which the daemon should be run.
20344 Defaults to @samp{"nslcd"}.
20348 @deftypevr {@code{nslcd-configuration} parameter} log-option log
20349 This option controls the way logging is done via a list containing
20350 SCHEME and LEVEL. The SCHEME argument may either be the symbols
20351 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
20352 argument is optional and specifies the log level. The log level may be
20353 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
20354 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
20355 specified log level or higher are logged.
20357 Defaults to @samp{("/var/log/nslcd" info)}.
20361 @deftypevr {@code{nslcd-configuration} parameter} list uri
20362 The list of LDAP server URIs. Normally, only the first server will be
20363 used with the following servers as fall-back.
20365 Defaults to @samp{("ldap://localhost:389/")}.
20369 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
20370 The version of the LDAP protocol to use. The default is to use the
20371 maximum version supported by the LDAP library.
20373 Defaults to @samp{disabled}.
20377 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
20378 Specifies the distinguished name with which to bind to the directory
20379 server for lookups. The default is to bind anonymously.
20381 Defaults to @samp{disabled}.
20385 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
20386 Specifies the credentials with which to bind. This option is only
20387 applicable when used with binddn.
20389 Defaults to @samp{disabled}.
20393 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
20394 Specifies the distinguished name to use when the root user tries to
20395 modify a user's password using the PAM module.
20397 Defaults to @samp{disabled}.
20401 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
20402 Specifies the credentials with which to bind if the root user tries to
20403 change a user's password. This option is only applicable when used with
20406 Defaults to @samp{disabled}.
20410 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
20411 Specifies the SASL mechanism to be used when performing SASL
20414 Defaults to @samp{disabled}.
20418 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
20419 Specifies the SASL realm to be used when performing SASL authentication.
20421 Defaults to @samp{disabled}.
20425 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
20426 Specifies the authentication identity to be used when performing SASL
20429 Defaults to @samp{disabled}.
20433 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
20434 Specifies the authorization identity to be used when performing SASL
20437 Defaults to @samp{disabled}.
20441 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
20442 Determines whether the LDAP server host name should be canonicalised. If
20443 this is enabled the LDAP library will do a reverse host name lookup. By
20444 default, it is left up to the LDAP library whether this check is
20447 Defaults to @samp{disabled}.
20451 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
20452 Set the name for the GSS-API Kerberos credentials cache.
20454 Defaults to @samp{disabled}.
20458 @deftypevr {@code{nslcd-configuration} parameter} string base
20459 The directory search base.
20461 Defaults to @samp{"dc=example,dc=com"}.
20465 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
20466 Specifies the search scope (subtree, onelevel, base or children). The
20467 default scope is subtree; base scope is almost never useful for name
20468 service lookups; children scope is not supported on all servers.
20470 Defaults to @samp{(subtree)}.
20474 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
20475 Specifies the policy for dereferencing aliases. The default policy is
20476 to never dereference aliases.
20478 Defaults to @samp{disabled}.
20482 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
20483 Specifies whether automatic referral chasing should be enabled. The
20484 default behaviour is to chase referrals.
20486 Defaults to @samp{disabled}.
20490 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
20491 This option allows for custom attributes to be looked up instead of the
20492 default RFC 2307 attributes. It is a list of maps, each consisting of
20493 the name of a map, the RFC 2307 attribute to match and the query
20494 expression for the attribute as it is available in the directory.
20496 Defaults to @samp{()}.
20500 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
20501 A list of filters consisting of the name of a map to which the filter
20502 applies and an LDAP search filter expression.
20504 Defaults to @samp{()}.
20508 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
20509 Specifies the time limit in seconds to use when connecting to the
20510 directory server. The default value is 10 seconds.
20512 Defaults to @samp{disabled}.
20516 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
20517 Specifies the time limit (in seconds) to wait for a response from the
20518 LDAP server. A value of zero, which is the default, is to wait
20519 indefinitely for searches to be completed.
20521 Defaults to @samp{disabled}.
20525 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
20526 Specifies the period if inactivity (in seconds) after which the con‐
20527 nection to the LDAP server will be closed. The default is not to time
20530 Defaults to @samp{disabled}.
20534 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
20535 Specifies the number of seconds to sleep when connecting to all LDAP
20536 servers fails. By default one second is waited between the first
20537 failure and the first retry.
20539 Defaults to @samp{disabled}.
20543 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
20544 Specifies the time after which the LDAP server is considered to be
20545 permanently unavailable. Once this time is reached retries will be done
20546 only once per this time period. The default value is 10 seconds.
20548 Defaults to @samp{disabled}.
20552 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
20553 Specifies whether to use SSL/TLS or not (the default is not to). If
20554 'start-tls is specified then StartTLS is used rather than raw LDAP over
20557 Defaults to @samp{disabled}.
20561 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
20562 Specifies what checks to perform on a server-supplied certificate. The
20563 meaning of the values is described in the ldap.conf(5) manual page.
20565 Defaults to @samp{disabled}.
20569 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
20570 Specifies the directory containing X.509 certificates for peer authen‐
20571 tication. This parameter is ignored when using GnuTLS.
20573 Defaults to @samp{disabled}.
20577 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
20578 Specifies the path to the X.509 certificate for peer authentication.
20580 Defaults to @samp{disabled}.
20584 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
20585 Specifies the path to an entropy source. This parameter is ignored when
20588 Defaults to @samp{disabled}.
20592 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
20593 Specifies the ciphers to use for TLS as a string.
20595 Defaults to @samp{disabled}.
20599 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
20600 Specifies the path to the file containing the local certificate for
20601 client TLS authentication.
20603 Defaults to @samp{disabled}.
20607 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
20608 Specifies the path to the file containing the private key for client TLS
20611 Defaults to @samp{disabled}.
20615 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
20616 Set this to a number greater than 0 to request paged results from the
20617 LDAP server in accordance with RFC2696. The default (0) is to not
20618 request paged results.
20620 Defaults to @samp{disabled}.
20624 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
20625 This option prevents group membership lookups through LDAP for the
20626 specified users. Alternatively, the value 'all-local may be used. With
20627 that value nslcd builds a full list of non-LDAP users on startup.
20629 Defaults to @samp{disabled}.
20633 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
20634 This option ensures that LDAP users with a numeric user id lower than
20635 the specified value are ignored.
20637 Defaults to @samp{disabled}.
20641 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
20642 This option specifies an offset that is added to all LDAP numeric user
20643 ids. This can be used to avoid user id collisions with local users.
20645 Defaults to @samp{disabled}.
20649 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
20650 This option specifies an offset that is added to all LDAP numeric group
20651 ids. This can be used to avoid user id collisions with local groups.
20653 Defaults to @samp{disabled}.
20657 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
20658 If this option is set, the member attribute of a group may point to
20659 another group. Members of nested groups are also returned in the higher
20660 level group and parent groups are returned when finding groups for a
20661 specific user. The default is not to perform extra searches for nested
20664 Defaults to @samp{disabled}.
20668 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
20669 If this option is set, the group member list is not retrieved when
20670 looking up groups. Lookups for finding which groups a user belongs to
20671 will remain functional so the user will likely still get the correct
20672 groups assigned on login.
20674 Defaults to @samp{disabled}.
20678 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
20679 If this option is set, functions which cause all user/group entries to
20680 be loaded from the directory will not succeed in doing so. This can
20681 dramatically reduce LDAP server load in situations where there are a
20682 great number of users and/or groups. This option is not recommended for
20683 most configurations.
20685 Defaults to @samp{disabled}.
20689 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
20690 This option can be used to specify how user and group names are verified
20691 within the system. This pattern is used to check all user and group
20692 names that are requested and returned from LDAP.
20694 Defaults to @samp{disabled}.
20698 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
20699 This specifies whether or not to perform searches using case-insensitive
20700 matching. Enabling this could open up the system to authorization
20701 bypass vulnerabilities and introduce nscd cache poisoning
20702 vulnerabilities which allow denial of service.
20704 Defaults to @samp{disabled}.
20708 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
20709 This option specifies whether password policy controls are requested and
20710 handled from the LDAP server when performing user authentication.
20712 Defaults to @samp{disabled}.
20716 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
20717 By default nslcd performs an LDAP search with the user's credentials
20718 after BIND (authentication) to ensure that the BIND operation was
20719 successful. The default search is a simple check to see if the user's
20720 DN exists. A search filter can be specified that will be used instead.
20721 It should return at least one entry.
20723 Defaults to @samp{disabled}.
20727 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
20728 This option allows flexible fine tuning of the authorisation check that
20729 should be performed. The search filter specified is executed and if any
20730 entries match, access is granted, otherwise access is denied.
20732 Defaults to @samp{disabled}.
20736 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
20737 If this option is set password modification using pam_ldap will be
20738 denied and the specified message will be presented to the user instead.
20739 The message can be used to direct the user to an alternative means of
20740 changing their password.
20742 Defaults to @samp{disabled}.
20746 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
20747 List of pam service names for which LDAP authentication should suffice.
20749 Defaults to @samp{()}.
20753 @c %end of generated documentation for nslcd-configuration
20757 @subsection Web Services
20762 The @code{(gnu services web)} module provides the Apache HTTP Server,
20763 the nginx web server, and also a fastcgi wrapper daemon.
20765 @subsubheading Apache HTTP Server
20767 @deffn {Scheme Variable} httpd-service-type
20768 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
20769 (@dfn{httpd}). The value for this service type is a
20770 @code{httpd-configuration} record.
20772 A simple example configuration is given below.
20775 (service httpd-service-type
20776 (httpd-configuration
20779 (server-name "www.example.com")
20780 (document-root "/srv/http/www.example.com")))))
20783 Other services can also extend the @code{httpd-service-type} to add to
20787 (simple-service 'www.example.com-server httpd-service-type
20791 (list (string-join '("ServerName www.example.com"
20792 "DocumentRoot /srv/http/www.example.com")
20797 The details for the @code{httpd-configuration}, @code{httpd-module},
20798 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
20801 @deffn {Data Type} httpd-configuration
20802 This data type represents the configuration for the httpd service.
20805 @item @code{package} (default: @code{httpd})
20806 The httpd package to use.
20808 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20809 The pid file used by the shepherd-service.
20811 @item @code{config} (default: @code{(httpd-config-file)})
20812 The configuration file to use with the httpd service. The default value
20813 is a @code{httpd-config-file} record, but this can also be a different
20814 G-expression that generates a file, for example a @code{plain-file}. A
20815 file outside of the store can also be specified through a string.
20820 @deffn {Data Type} httpd-module
20821 This data type represents a module for the httpd service.
20825 The name of the module.
20828 The file for the module. This can be relative to the httpd package being
20829 used, the absolute location of a file, or a G-expression for a file
20830 within the store, for example @code{(file-append mod-wsgi
20831 "/modules/mod_wsgi.so")}.
20836 @defvr {Scheme Variable} %default-httpd-modules
20837 A default list of @code{httpd-module} objects.
20840 @deffn {Data Type} httpd-config-file
20841 This data type represents a configuration file for the httpd service.
20844 @item @code{modules} (default: @code{%default-httpd-modules})
20845 The modules to load. Additional modules can be added here, or loaded by
20846 additional configuration.
20848 For example, in order to handle requests for PHP files, you can use Apache’s
20849 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
20852 (service httpd-service-type
20853 (httpd-configuration
20858 (name "proxy_module")
20859 (file "modules/mod_proxy.so"))
20861 (name "proxy_fcgi_module")
20862 (file "modules/mod_proxy_fcgi.so"))
20863 %default-httpd-modules))
20864 (extra-config (list "\
20865 <FilesMatch \\.php$>
20866 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
20867 </FilesMatch>"))))))
20868 (service php-fpm-service-type
20869 (php-fpm-configuration
20870 (socket "/var/run/php-fpm.sock")
20871 (socket-group "httpd")))
20874 @item @code{server-root} (default: @code{httpd})
20875 The @code{ServerRoot} in the configuration file, defaults to the httpd
20876 package. Directives including @code{Include} and @code{LoadModule} are
20877 taken as relative to the server root.
20879 @item @code{server-name} (default: @code{#f})
20880 The @code{ServerName} in the configuration file, used to specify the
20881 request scheme, hostname and port that the server uses to identify
20884 This doesn't need to be set in the server config, and can be specified
20885 in virtual hosts. The default is @code{#f} to not specify a
20888 @item @code{document-root} (default: @code{"/srv/http"})
20889 The @code{DocumentRoot} from which files will be served.
20891 @item @code{listen} (default: @code{'("80")})
20892 The list of values for the @code{Listen} directives in the config
20893 file. The value should be a list of strings, when each string can
20894 specify the port number to listen on, and optionally the IP address and
20897 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20898 The @code{PidFile} to use. This should match the @code{pid-file} set in
20899 the @code{httpd-configuration} so that the Shepherd service is
20900 configured correctly.
20902 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
20903 The @code{ErrorLog} to which the server will log errors.
20905 @item @code{user} (default: @code{"httpd"})
20906 The @code{User} which the server will answer requests as.
20908 @item @code{group} (default: @code{"httpd"})
20909 The @code{Group} which the server will answer requests as.
20911 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
20912 A flat list of strings and G-expressions which will be added to the end
20913 of the configuration file.
20915 Any values which the service is extended with will be appended to this
20921 @deffn {Data Type} httpd-virtualhost
20922 This data type represents a virtualhost configuration block for the httpd service.
20924 These should be added to the extra-config for the httpd-service.
20927 (simple-service 'www.example.com-server httpd-service-type
20931 (list (string-join '("ServerName www.example.com"
20932 "DocumentRoot /srv/http/www.example.com")
20937 @item @code{addresses-and-ports}
20938 The addresses and ports for the @code{VirtualHost} directive.
20940 @item @code{contents}
20941 The contents of the @code{VirtualHost} directive, this should be a list
20942 of strings and G-expressions.
20947 @subsubheading NGINX
20949 @deffn {Scheme Variable} nginx-service-type
20950 Service type for the @uref{https://nginx.org/,NGinx} web server. The
20951 value for this service type is a @code{<nginx-configuration>} record.
20953 A simple example configuration is given below.
20956 (service nginx-service-type
20957 (nginx-configuration
20959 (list (nginx-server-configuration
20960 (server-name '("www.example.com"))
20961 (root "/srv/http/www.example.com"))))))
20964 In addition to adding server blocks to the service configuration
20965 directly, this service can be extended by other services to add server
20966 blocks, as in this example:
20969 (simple-service 'my-extra-server nginx-service-type
20970 (list (nginx-server-configuration
20971 (root "/srv/http/extra-website")
20972 (try-files (list "$uri" "$uri/index.html")))))
20976 At startup, @command{nginx} has not yet read its configuration file, so
20977 it uses a default file to log error messages. If it fails to load its
20978 configuration file, that is where error messages are logged. After the
20979 configuration file is loaded, the default error log file changes as per
20980 configuration. In our case, startup error messages can be found in
20981 @file{/var/run/nginx/logs/error.log}, and after configuration in
20982 @file{/var/log/nginx/error.log}. The second location can be changed
20983 with the @var{log-directory} configuration option.
20985 @deffn {Data Type} nginx-configuration
20986 This data type represents the configuration for NGinx. Some
20987 configuration can be done through this and the other provided record
20988 types, or alternatively, a config file can be provided.
20991 @item @code{nginx} (default: @code{nginx})
20992 The nginx package to use.
20994 @item @code{log-directory} (default: @code{"/var/log/nginx"})
20995 The directory to which NGinx will write log files.
20997 @item @code{run-directory} (default: @code{"/var/run/nginx"})
20998 The directory in which NGinx will create a pid file, and write temporary
21001 @item @code{server-blocks} (default: @code{'()})
21002 A list of @dfn{server blocks} to create in the generated configuration
21003 file, the elements should be of type
21004 @code{<nginx-server-configuration>}.
21006 The following example would setup NGinx to serve @code{www.example.com}
21007 from the @code{/srv/http/www.example.com} directory, without using
21010 (service nginx-service-type
21011 (nginx-configuration
21013 (list (nginx-server-configuration
21014 (server-name '("www.example.com"))
21015 (root "/srv/http/www.example.com"))))))
21018 @item @code{upstream-blocks} (default: @code{'()})
21019 A list of @dfn{upstream blocks} to create in the generated configuration
21020 file, the elements should be of type
21021 @code{<nginx-upstream-configuration>}.
21023 Configuring upstreams through the @code{upstream-blocks} can be useful
21024 when combined with @code{locations} in the
21025 @code{<nginx-server-configuration>} records. The following example
21026 creates a server configuration with one location configuration, that
21027 will proxy requests to a upstream configuration, which will handle
21028 requests with two servers.
21033 (nginx-configuration
21035 (list (nginx-server-configuration
21036 (server-name '("www.example.com"))
21037 (root "/srv/http/www.example.com")
21040 (nginx-location-configuration
21042 (body '("proxy_pass http://server-proxy;"))))))))
21044 (list (nginx-upstream-configuration
21045 (name "server-proxy")
21046 (servers (list "server1.example.com"
21047 "server2.example.com")))))))
21050 @item @code{file} (default: @code{#f})
21051 If a configuration @var{file} is provided, this will be used, rather than
21052 generating a configuration file from the provided @code{log-directory},
21053 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
21054 proper operation, these arguments should match what is in @var{file} to ensure
21055 that the directories are created when the service is activated.
21057 This can be useful if you have an existing configuration file, or it's
21058 not possible to do what is required through the other parts of the
21059 nginx-configuration record.
21061 @item @code{server-names-hash-bucket-size} (default: @code{#f})
21062 Bucket size for the server names hash tables, defaults to @code{#f} to
21063 use the size of the processors cache line.
21065 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
21066 Maximum bucket size for the server names hash tables.
21068 @item @code{modules} (default: @code{'()})
21069 List of nginx dynamic modules to load. This should be a list of file
21070 names of loadable modules, as in this example:
21075 (file-append nginx-accept-language-module "\
21076 /etc/nginx/modules/ngx_http_accept_language_module.so")))
21079 @item @code{global-directives} (default: @code{'((events . ()))})
21080 Association list of global directives for the top level of the nginx
21081 configuration. Values may themselves be association lists.
21085 `((worker_processes . 16)
21087 (events . ((worker_connections . 1024)))))
21090 @item @code{extra-content} (default: @code{""})
21091 Extra content for the @code{http} block. Should be string or a string
21092 valued G-expression.
21097 @deftp {Data Type} nginx-server-configuration
21098 Data type representing the configuration of an nginx server block.
21099 This type has the following parameters:
21102 @item @code{listen} (default: @code{'("80" "443 ssl")})
21103 Each @code{listen} directive sets the address and port for IP, or the
21104 path for a UNIX-domain socket on which the server will accept requests.
21105 Both address and port, or only address or only port can be specified.
21106 An address may also be a hostname, for example:
21109 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
21112 @item @code{server-name} (default: @code{(list 'default)})
21113 A list of server names this server represents. @code{'default} represents the
21114 default server for connections matching no other server.
21116 @item @code{root} (default: @code{"/srv/http"})
21117 Root of the website nginx will serve.
21119 @item @code{locations} (default: @code{'()})
21120 A list of @dfn{nginx-location-configuration} or
21121 @dfn{nginx-named-location-configuration} records to use within this
21124 @item @code{index} (default: @code{(list "index.html")})
21125 Index files to look for when clients ask for a directory. If it cannot be found,
21126 Nginx will send the list of files in the directory.
21128 @item @code{try-files} (default: @code{'()})
21129 A list of files whose existence is checked in the specified order.
21130 @code{nginx} will use the first file it finds to process the request.
21132 @item @code{ssl-certificate} (default: @code{#f})
21133 Where to find the certificate for secure connections. Set it to @code{#f} if
21134 you don't have a certificate or you don't want to use HTTPS.
21136 @item @code{ssl-certificate-key} (default: @code{#f})
21137 Where to find the private key for secure connections. Set it to @code{#f} if
21138 you don't have a key or you don't want to use HTTPS.
21140 @item @code{server-tokens?} (default: @code{#f})
21141 Whether the server should add its configuration to response.
21143 @item @code{raw-content} (default: @code{'()})
21144 A list of raw lines added to the server block.
21149 @deftp {Data Type} nginx-upstream-configuration
21150 Data type representing the configuration of an nginx @code{upstream}
21151 block. This type has the following parameters:
21155 Name for this group of servers.
21157 @item @code{servers}
21158 Specify the addresses of the servers in the group. The address can be
21159 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
21160 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
21161 prefix @samp{unix:}. For addresses using an IP address or domain name,
21162 the default port is 80, and a different port can be specified
21168 @deftp {Data Type} nginx-location-configuration
21169 Data type representing the configuration of an nginx @code{location}
21170 block. This type has the following parameters:
21174 URI which this location block matches.
21176 @anchor{nginx-location-configuration body}
21178 Body of the location block, specified as a list of strings. This can contain
21180 configuration directives. For example, to pass requests to a upstream
21181 server group defined using an @code{nginx-upstream-configuration} block,
21182 the following directive would be specified in the body @samp{(list "proxy_pass
21183 http://upstream-name;")}.
21188 @deftp {Data Type} nginx-named-location-configuration
21189 Data type representing the configuration of an nginx named location
21190 block. Named location blocks are used for request redirection, and not
21191 used for regular request processing. This type has the following
21196 Name to identify this location block.
21199 @xref{nginx-location-configuration body}, as the body for named location
21200 blocks can be used in a similar way to the
21201 @code{nginx-location-configuration body}. One restriction is that the
21202 body of a named location block cannot contain location blocks.
21207 @subsubheading Varnish Cache
21209 Varnish is a fast cache server that sits in between web applications
21210 and end users. It proxies requests from clients and caches the
21211 accessed URLs such that multiple requests for the same resource only
21212 creates one request to the back-end.
21214 @defvr {Scheme Variable} varnish-service-type
21215 Service type for the Varnish daemon.
21218 @deftp {Data Type} varnish-configuration
21219 Data type representing the @code{varnish} service configuration.
21220 This type has the following parameters:
21223 @item @code{package} (default: @code{varnish})
21224 The Varnish package to use.
21226 @item @code{name} (default: @code{"default"})
21227 A name for this Varnish instance. Varnish will create a directory in
21228 @file{/var/varnish/} with this name and keep temporary files there. If
21229 the name starts with a forward slash, it is interpreted as an absolute
21232 Pass the @code{-n} argument to other Varnish programs to connect to the
21233 named instance, e.g.@: @command{varnishncsa -n default}.
21235 @item @code{backend} (default: @code{"localhost:8080"})
21236 The backend to use. This option has no effect if @code{vcl} is set.
21238 @item @code{vcl} (default: #f)
21239 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
21240 is @code{#f}, Varnish will proxy @code{backend} using the default
21241 configuration. Otherwise this must be a file-like object with valid
21244 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
21245 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
21246 can do something along these lines:
21249 (define %gnu-mirror
21250 (plain-file "gnu.vcl"
21252 backend gnu @{ .host = \"www.gnu.org\"; @}"))
21256 (services (cons (service varnish-service-type
21257 (varnish-configuration
21259 (vcl %gnu-mirror)))
21263 The configuration of an already running Varnish instance can be inspected
21264 and changed using the @command{varnishadm} program.
21266 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
21267 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
21268 comprehensive documentation on Varnish and its configuration language.
21270 @item @code{listen} (default: @code{'("localhost:80")})
21271 List of addresses Varnish will listen on.
21273 @item @code{storage} (default: @code{'("malloc,128m")})
21274 List of storage backends that will be available in VCL.
21276 @item @code{parameters} (default: @code{'()})
21277 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
21279 @item @code{extra-options} (default: @code{'()})
21280 Additional arguments to pass to the @command{varnishd} process.
21285 @subsubheading Patchwork
21287 Patchwork is a patch tracking system. It can collect patches sent to a
21288 mailing list, and display them in a web interface.
21290 @defvr {Scheme Variable} patchwork-service-type
21291 Service type for Patchwork.
21294 The following example is an example of a minimal service for Patchwork, for
21295 the @code{patchwork.example.com} domain.
21298 (service patchwork-service-type
21299 (patchwork-configuration
21300 (domain "patchwork.example.com")
21302 (patchwork-settings-module
21303 (allowed-hosts (list domain))
21304 (default-from-email "patchwork@@patchwork.example.com")))
21305 (getmail-retriever-config
21306 (getmail-retriever-configuration
21307 (type "SimpleIMAPSSLRetriever")
21308 (server "imap.example.com")
21310 (username "patchwork")
21312 (list (file-append coreutils "/bin/cat")
21313 "/etc/getmail-patchwork-imap-password"))
21315 '((mailboxes . ("Patches"))))))))
21319 There are three records for configuring the Patchwork service. The
21320 @code{<patchwork-configuration>} relates to the configuration for Patchwork
21321 within the HTTPD service.
21323 The @code{settings-module} field within the @code{<patchwork-configuration>}
21324 record can be populated with the @code{<patchwork-settings-module>} record,
21325 which describes a settings module that is generated within the Guix store.
21327 For the @code{database-configuration} field within the
21328 @code{<patchwork-settings-module>}, the
21329 @code{<patchwork-database-configuration>} must be used.
21331 @deftp {Data Type} patchwork-configuration
21332 Data type representing the Patchwork service configuration. This type has the
21333 following parameters:
21336 @item @code{patchwork} (default: @code{patchwork})
21337 The Patchwork package to use.
21339 @item @code{domain}
21340 The domain to use for Patchwork, this is used in the HTTPD service virtual
21343 @item @code{settings-module}
21344 The settings module to use for Patchwork. As a Django application, Patchwork
21345 is configured with a Python module containing the settings. This can either be
21346 an instance of the @code{<patchwork-settings-module>} record, any other record
21347 that represents the settings in the store, or a directory outside of the
21350 @item @code{static-path} (default: @code{"/static/"})
21351 The path under which the HTTPD service should serve the static files.
21353 @item @code{getmail-retriever-config}
21354 The getmail-retriever-configuration record value to use with
21355 Patchwork. Getmail will be configured with this value, the messages will be
21356 delivered to Patchwork.
21361 @deftp {Data Type} patchwork-settings-module
21362 Data type representing a settings module for Patchwork. Some of these
21363 settings relate directly to Patchwork, but others relate to Django, the web
21364 framework used by Patchwork, or the Django Rest Framework library. This type
21365 has the following parameters:
21368 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
21369 The database connection settings used for Patchwork. See the
21370 @code{<patchwork-database-configuration>} record type for more information.
21372 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
21373 Patchwork, as a Django web application uses a secret key for cryptographically
21374 signing values. This file should contain a unique unpredictable value.
21376 If this file does not exist, it will be created and populated with a random
21377 value by the patchwork-setup shepherd service.
21379 This setting relates to Django.
21381 @item @code{allowed-hosts}
21382 A list of valid hosts for this Patchwork service. This should at least include
21383 the domain specified in the @code{<patchwork-configuration>} record.
21385 This is a Django setting.
21387 @item @code{default-from-email}
21388 The email address from which Patchwork should send email by default.
21390 This is a Patchwork setting.
21392 @item @code{static-url} (default: @code{#f})
21393 The URL to use when serving static assets. It can be part of a URL, or a full
21394 URL, but must end in a @code{/}.
21396 If the default value is used, the @code{static-path} value from the
21397 @code{<patchwork-configuration>} record will be used.
21399 This is a Django setting.
21401 @item @code{admins} (default: @code{'()})
21402 Email addresses to send the details of errors that occur. Each value should
21403 be a list containing two elements, the name and then the email address.
21405 This is a Django setting.
21407 @item @code{debug?} (default: @code{#f})
21408 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
21409 messages will be shown.
21411 This is a Django setting.
21413 @item @code{enable-rest-api?} (default: @code{#t})
21414 Whether to enable the Patchwork REST API.
21416 This is a Patchwork setting.
21418 @item @code{enable-xmlrpc?} (default: @code{#t})
21419 Whether to enable the XML RPC API.
21421 This is a Patchwork setting.
21423 @item @code{force-https-links?} (default: @code{#t})
21424 Whether to use HTTPS links on Patchwork pages.
21426 This is a Patchwork setting.
21428 @item @code{extra-settings} (default: @code{""})
21429 Extra code to place at the end of the Patchwork settings module.
21434 @deftp {Data Type} patchwork-database-configuration
21435 Data type representing the database configuration for Patchwork.
21438 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
21439 The database engine to use.
21441 @item @code{name} (default: @code{"patchwork"})
21442 The name of the database to use.
21444 @item @code{user} (default: @code{"httpd"})
21445 The user to connect to the database as.
21447 @item @code{password} (default: @code{""})
21448 The password to use when connecting to the database.
21450 @item @code{host} (default: @code{""})
21451 The host to make the database connection to.
21453 @item @code{port} (default: @code{""})
21454 The port on which to connect to the database.
21459 @subsubheading Mumi
21461 @cindex Mumi, Debbugs Web interface
21462 @cindex Debbugs, Mumi Web interface
21463 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
21464 Web interface to the Debbugs bug tracker, by default for
21465 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
21466 but it also fetches and indexes mail retrieved from Debbugs.
21468 @defvr {Scheme Variable} mumi-service-type
21469 This is the service type for Mumi.
21472 @deftp {Data Type} mumi-configuration
21473 Data type representing the Mumi service configuration. This type has the
21477 @item @code{mumi} (default: @code{mumi})
21478 The Mumi package to use.
21480 @item @code{mailer?} (default: @code{#true})
21481 Whether to enable or disable the mailer component.
21483 @item @code{mumi-configuration-sender}
21484 The email address used as the sender for comments.
21486 @item @code{mumi-configuration-smtp}
21487 A URI to configure the SMTP settings for Mailutils. This could be
21488 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
21489 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
21490 mailutils, GNU@tie{}Mailutils}.
21496 @subsubheading FastCGI
21499 FastCGI is an interface between the front-end and the back-end of a web
21500 service. It is a somewhat legacy facility; new web services should
21501 generally just talk HTTP between the front-end and the back-end.
21502 However there are a number of back-end services such as PHP or the
21503 optimized HTTP Git repository access that use FastCGI, so we have
21504 support for it in Guix.
21506 To use FastCGI, you configure the front-end web server (e.g., nginx) to
21507 dispatch some subset of its requests to the fastcgi backend, which
21508 listens on a local TCP or UNIX socket. There is an intermediary
21509 @code{fcgiwrap} program that sits between the actual backend process and
21510 the web server. The front-end indicates which backend program to run,
21511 passing that information to the @code{fcgiwrap} process.
21513 @defvr {Scheme Variable} fcgiwrap-service-type
21514 A service type for the @code{fcgiwrap} FastCGI proxy.
21517 @deftp {Data Type} fcgiwrap-configuration
21518 Data type representing the configuration of the @code{fcgiwrap} service.
21519 This type has the following parameters:
21521 @item @code{package} (default: @code{fcgiwrap})
21522 The fcgiwrap package to use.
21524 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
21525 The socket on which the @code{fcgiwrap} process should listen, as a
21526 string. Valid @var{socket} values include
21527 @code{unix:@var{/path/to/unix/socket}},
21528 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
21529 @code{tcp6:[@var{ipv6_addr}]:port}.
21531 @item @code{user} (default: @code{fcgiwrap})
21532 @itemx @code{group} (default: @code{fcgiwrap})
21533 The user and group names, as strings, under which to run the
21534 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
21535 the user asks for the specific user or group names @code{fcgiwrap} that
21536 the corresponding user and/or group is present on the system.
21538 It is possible to configure a FastCGI-backed web service to pass HTTP
21539 authentication information from the front-end to the back-end, and to
21540 allow @code{fcgiwrap} to run the back-end process as a corresponding
21541 local user. To enable this capability on the back-end, run
21542 @code{fcgiwrap} as the @code{root} user and group. Note that this
21543 capability also has to be configured on the front-end as well.
21548 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
21549 with some additional features useful for sites of any size.
21551 These features include:
21553 @item Adaptive process spawning
21554 @item Basic statistics (similar to Apache's mod_status)
21555 @item Advanced process management with graceful stop/start
21556 @item Ability to start workers with different uid/gid/chroot/environment
21557 and different php.ini (replaces safe_mode)
21558 @item Stdout & stderr logging
21559 @item Emergency restart in case of accidental opcode cache destruction
21560 @item Accelerated upload support
21561 @item Support for a "slowlog"
21562 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
21563 a special function to finish request & flush all data while continuing to do
21564 something time-consuming (video converting, stats processing, etc.)
21566 ...@: and much more.
21568 @defvr {Scheme Variable} php-fpm-service-type
21569 A Service type for @code{php-fpm}.
21572 @deftp {Data Type} php-fpm-configuration
21573 Data Type for php-fpm service configuration.
21575 @item @code{php} (default: @code{php})
21576 The php package to use.
21577 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
21578 The address on which to accept FastCGI requests. Valid syntaxes are:
21580 @item @code{"ip.add.re.ss:port"}
21581 Listen on a TCP socket to a specific address on a specific port.
21582 @item @code{"port"}
21583 Listen on a TCP socket to all addresses on a specific port.
21584 @item @code{"/path/to/unix/socket"}
21585 Listen on a unix socket.
21588 @item @code{user} (default: @code{php-fpm})
21589 User who will own the php worker processes.
21590 @item @code{group} (default: @code{php-fpm})
21591 Group of the worker processes.
21592 @item @code{socket-user} (default: @code{php-fpm})
21593 User who can speak to the php-fpm socket.
21594 @item @code{socket-group} (default: @code{nginx})
21595 Group that can speak to the php-fpm socket.
21596 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
21597 The process id of the php-fpm process is written to this file
21598 once the service has started.
21599 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
21600 Log for the php-fpm master process.
21601 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
21602 Detailed settings for the php-fpm process manager.
21605 @item @code{<php-fpm-dynamic-process-manager-configuration>}
21606 @item @code{<php-fpm-static-process-manager-configuration>}
21607 @item @code{<php-fpm-on-demand-process-manager-configuration>}
21609 @item @code{display-errors} (default @code{#f})
21610 Determines whether php errors and warning should be sent to clients
21611 and displayed in their browsers.
21612 This is useful for local php development, but a security risk for public sites,
21613 as error messages can reveal passwords and personal data.
21614 @item @code{timezone} (default @code{#f})
21615 Specifies @code{php_admin_value[date.timezone]} parameter.
21616 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
21617 This file will log the @code{stderr} outputs of php worker processes.
21618 Can be set to @code{#f} to disable logging.
21619 @item @code{file} (default @code{#f})
21620 An optional override of the whole configuration.
21621 You can use the @code{mixed-text-file} function or an absolute filepath for it.
21625 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
21626 Data Type for the @code{dynamic} php-fpm process manager. With the
21627 @code{dynamic} process manager, spare worker processes are kept around
21628 based on it's configured limits.
21630 @item @code{max-children} (default: @code{5})
21631 Maximum of worker processes.
21632 @item @code{start-servers} (default: @code{2})
21633 How many worker processes should be started on start-up.
21634 @item @code{min-spare-servers} (default: @code{1})
21635 How many spare worker processes should be kept around at minimum.
21636 @item @code{max-spare-servers} (default: @code{3})
21637 How many spare worker processes should be kept around at maximum.
21641 @deftp {Data type} php-fpm-static-process-manager-configuration
21642 Data Type for the @code{static} php-fpm process manager. With the
21643 @code{static} process manager, an unchanging number of worker processes
21646 @item @code{max-children} (default: @code{5})
21647 Maximum of worker processes.
21651 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
21652 Data Type for the @code{on-demand} php-fpm process manager. With the
21653 @code{on-demand} process manager, worker processes are only created as
21656 @item @code{max-children} (default: @code{5})
21657 Maximum of worker processes.
21658 @item @code{process-idle-timeout} (default: @code{10})
21659 The time in seconds after which a process with no requests is killed.
21664 @deffn {Scheme Procedure} nginx-php-location @
21665 [#:nginx-package nginx] @
21666 [socket (string-append "/var/run/php" @
21667 (version-major (package-version php)) @
21669 A helper function to quickly add php to an @code{nginx-server-configuration}.
21672 A simple services setup for nginx with php can look like this:
21674 (services (cons* (service dhcp-client-service-type)
21675 (service php-fpm-service-type)
21676 (service nginx-service-type
21677 (nginx-server-configuration
21678 (server-name '("example.com"))
21679 (root "/srv/http/")
21681 (list (nginx-php-location)))
21683 (ssl-certificate #f)
21684 (ssl-certificate-key #f)))
21688 @cindex cat-avatar-generator
21689 The cat avatar generator is a simple service to demonstrate the use of php-fpm
21690 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
21691 the hash of a user's email address.
21693 @deffn {Scheme Procedure} cat-avatar-generator-service @
21694 [#:cache-dir "/var/cache/cat-avatar-generator"] @
21695 [#:package cat-avatar-generator] @
21696 [#:configuration (nginx-server-configuration)]
21697 Returns an nginx-server-configuration that inherits @code{configuration}. It
21698 extends the nginx configuration to add a server block that serves @code{package},
21699 a version of cat-avatar-generator. During execution, cat-avatar-generator will
21700 be able to use @code{cache-dir} as its cache directory.
21703 A simple setup for cat-avatar-generator can look like this:
21705 (services (cons* (cat-avatar-generator-service
21707 (nginx-server-configuration
21708 (server-name '("example.com"))))
21713 @subsubheading Hpcguix-web
21715 @cindex hpcguix-web
21716 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
21717 program is a customizable web interface to browse Guix packages,
21718 initially designed for users of high-performance computing (HPC)
21721 @defvr {Scheme Variable} hpcguix-web-service-type
21722 The service type for @code{hpcguix-web}.
21725 @deftp {Data Type} hpcguix-web-configuration
21726 Data type for the hpcguix-web service configuration.
21730 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
21731 configuration. The main items available in this spec are:
21734 @item @code{title-prefix} (default: @code{"hpcguix | "})
21735 The page title prefix.
21737 @item @code{guix-command} (default: @code{"guix"})
21738 The @command{guix} command.
21740 @item @code{package-filter-proc} (default: @code{(const #t)})
21741 A procedure specifying how to filter packages that are displayed.
21743 @item @code{package-page-extension-proc} (default: @code{(const '())})
21744 Extension package for @code{hpcguix-web}.
21746 @item @code{menu} (default: @code{'()})
21747 Additional entry in page @code{menu}.
21749 @item @code{channels} (default: @code{%default-channels})
21750 List of channels from which the package list is built (@pxref{Channels}).
21752 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
21753 The expiration time, in seconds, after which the package list is rebuilt from
21754 the latest instances of the given channels.
21757 See the hpcguix-web repository for a
21758 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
21761 @item @code{package} (default: @code{hpcguix-web})
21762 The hpcguix-web package to use.
21766 A typical hpcguix-web service declaration looks like this:
21769 (service hpcguix-web-service-type
21770 (hpcguix-web-configuration
21772 #~(define site-config
21773 (hpcweb-configuration
21774 (title-prefix "Guix-HPC - ")
21775 (menu '(("/about" "ABOUT"))))))))
21779 The hpcguix-web service periodically updates the package list it publishes by
21780 pulling channels from Git. To that end, it needs to access X.509 certificates
21781 so that it can authenticate Git servers when communicating over HTTPS, and it
21782 assumes that @file{/etc/ssl/certs} contains those certificates.
21784 Thus, make sure to add @code{nss-certs} or another certificate package to the
21785 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
21786 more information on X.509 certificates.
21789 @node Certificate Services
21790 @subsection Certificate Services
21793 @cindex HTTP, HTTPS
21794 @cindex Let's Encrypt
21795 @cindex TLS certificates
21796 The @code{(gnu services certbot)} module provides a service to
21797 automatically obtain a valid TLS certificate from the Let's Encrypt
21798 certificate authority. These certificates can then be used to serve
21799 content securely over HTTPS or other TLS-based protocols, with the
21800 knowledge that the client will be able to verify the server's
21803 @url{https://letsencrypt.org/, Let's Encrypt} provides the
21804 @code{certbot} tool to automate the certification process. This tool
21805 first securely generates a key on the server. It then makes a request
21806 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
21807 checks that the request originates from the host in question by using a
21808 challenge-response protocol, requiring the server to provide its
21809 response over HTTP. If that protocol completes successfully, the CA
21810 signs the key, resulting in a certificate. That certificate is valid
21811 for a limited period of time, and therefore to continue to provide TLS
21812 services, the server needs to periodically ask the CA to renew its
21815 The certbot service automates this process: the initial key
21816 generation, the initial certification request to the Let's Encrypt
21817 service, the web server challenge/response integration, writing the
21818 certificate to disk, the automated periodic renewals, and the deployment
21819 tasks associated with the renewal (e.g.@: reloading services, copying keys
21820 with different permissions).
21822 Certbot is run twice a day, at a random minute within the hour. It
21823 won't do anything until your certificates are due for renewal or
21824 revoked, but running it regularly would give your service a chance of
21825 staying online in case a Let's Encrypt-initiated revocation happened for
21828 By using this service, you agree to the ACME Subscriber Agreement, which
21829 can be found there:
21830 @url{https://acme-v01.api.letsencrypt.org/directory}.
21832 @defvr {Scheme Variable} certbot-service-type
21833 A service type for the @code{certbot} Let's Encrypt client. Its value
21834 must be a @code{certbot-configuration} record as in this example:
21837 (define %nginx-deploy-hook
21839 "nginx-deploy-hook"
21840 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
21841 (kill pid SIGHUP))))
21843 (service certbot-service-type
21844 (certbot-configuration
21845 (email "foo@@example.net")
21848 (certificate-configuration
21849 (domains '("example.net" "www.example.net"))
21850 (deploy-hook %nginx-deploy-hook))
21851 (certificate-configuration
21852 (domains '("bar.example.net")))))))
21855 See below for details about @code{certbot-configuration}.
21858 @deftp {Data Type} certbot-configuration
21859 Data type representing the configuration of the @code{certbot} service.
21860 This type has the following parameters:
21863 @item @code{package} (default: @code{certbot})
21864 The certbot package to use.
21866 @item @code{webroot} (default: @code{/var/www})
21867 The directory from which to serve the Let's Encrypt challenge/response
21870 @item @code{certificates} (default: @code{()})
21871 A list of @code{certificates-configuration}s for which to generate
21872 certificates and request signatures. Each certificate has a @code{name}
21873 and several @code{domains}.
21876 Mandatory email used for registration, recovery contact, and important
21877 account notifications.
21879 @item @code{server} (default: @code{#f})
21880 Optional URL of ACME server. Setting this overrides certbot's default,
21881 which is the Let's Encrypt server.
21883 @item @code{rsa-key-size} (default: @code{2048})
21884 Size of the RSA key.
21886 @item @code{default-location} (default: @i{see below})
21887 The default @code{nginx-location-configuration}. Because @code{certbot}
21888 needs to be able to serve challenges and responses, it needs to be able
21889 to run a web server. It does so by extending the @code{nginx} web
21890 service with an @code{nginx-server-configuration} listening on the
21891 @var{domains} on port 80, and which has a
21892 @code{nginx-location-configuration} for the @code{/.well-known/} URI
21893 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
21894 these nginx configuration data types.
21896 Requests to other URL paths will be matched by the
21897 @code{default-location}, which if present is added to all
21898 @code{nginx-server-configuration}s.
21900 By default, the @code{default-location} will issue a redirect from
21901 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
21902 you to define what to serve on your site via @code{https}.
21904 Pass @code{#f} to not issue a default location.
21908 @deftp {Data Type} certificate-configuration
21909 Data type representing the configuration of a certificate.
21910 This type has the following parameters:
21913 @item @code{name} (default: @i{see below})
21914 This name is used by Certbot for housekeeping and in file paths; it
21915 doesn't affect the content of the certificate itself. To see
21916 certificate names, run @code{certbot certificates}.
21918 Its default is the first provided domain.
21920 @item @code{domains} (default: @code{()})
21921 The first domain provided will be the subject CN of the certificate, and
21922 all domains will be Subject Alternative Names on the certificate.
21924 @item @code{challenge} (default: @code{#f})
21925 The challenge type that has to be run by certbot. If @code{#f} is specified,
21926 default to the HTTP challenge. If a value is specified, defaults to the
21927 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
21928 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
21929 and gives Let's Encrypt permission to log the public IP address of the
21930 requesting machine.
21932 @item @code{authentication-hook} (default: @code{#f})
21933 Command to be run in a shell once for each certificate challenge to be
21934 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
21935 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
21936 contains the validation string and @code{$CERTBOT_TOKEN} contains the
21937 file name of the resource requested when performing an HTTP-01 challenge.
21939 @item @code{cleanup-hook} (default: @code{#f})
21940 Command to be run in a shell once for each certificate challenge that
21941 have been answered by the @code{auth-hook}. For this command, the shell
21942 variables available in the @code{auth-hook} script are still available, and
21943 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
21944 of the @code{auth-hook} script.
21946 @item @code{deploy-hook} (default: @code{#f})
21947 Command to be run in a shell once for each successfully issued
21948 certificate. For this command, the shell variable
21949 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
21950 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
21951 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
21952 contain a space-delimited list of renewed certificate domains (for
21953 example, @samp{"example.com www.example.com"}.
21958 For each @code{certificate-configuration}, the certificate is saved to
21959 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
21960 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
21962 @subsection DNS Services
21963 @cindex DNS (domain name system)
21964 @cindex domain name system (DNS)
21966 The @code{(gnu services dns)} module provides services related to the
21967 @dfn{domain name system} (DNS). It provides a server service for hosting
21968 an @emph{authoritative} DNS server for multiple zones, slave or master.
21969 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
21970 caching and forwarding DNS server for the LAN, which uses
21971 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
21973 @subsubheading Knot Service
21975 An example configuration of an authoritative server for two zones, one master
21979 (define-zone-entries example.org.zone
21980 ;; Name TTL Class Type Data
21981 ("@@" "" "IN" "A" "127.0.0.1")
21982 ("@@" "" "IN" "NS" "ns")
21983 ("ns" "" "IN" "A" "127.0.0.1"))
21985 (define master-zone
21986 (knot-zone-configuration
21987 (domain "example.org")
21989 (origin "example.org")
21990 (entries example.org.zone)))))
21993 (knot-zone-configuration
21994 (domain "plop.org")
21995 (dnssec-policy "default")
21996 (master (list "plop-master"))))
21998 (define plop-master
21999 (knot-remote-configuration
22001 (address (list "208.76.58.171"))))
22005 (services (cons* (service knot-service-type
22006 (knot-configuration
22007 (remotes (list plop-master))
22008 (zones (list master-zone slave-zone))))
22013 @deffn {Scheme Variable} knot-service-type
22014 This is the type for the Knot DNS server.
22016 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
22017 zones, that is to say domain names you would buy from a registrar. This server
22018 is not a resolver, meaning that it can only resolve names for which it is
22019 authoritative. This server can be configured to serve zones as a master server
22020 or a slave server as a per-zone basis. Slave zones will get their data from
22021 masters, and will serve it as an authoritative server. From the point of view
22022 of a resolver, there is no difference between master and slave.
22024 The following data types are used to configure the Knot DNS server:
22027 @deftp {Data Type} knot-key-configuration
22028 Data type representing a key.
22029 This type has the following parameters:
22032 @item @code{id} (default: @code{""})
22033 An identifier for other configuration fields to refer to this key. IDs must
22034 be unique and must not be empty.
22036 @item @code{algorithm} (default: @code{#f})
22037 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
22038 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
22039 and @code{'hmac-sha512}.
22041 @item @code{secret} (default: @code{""})
22042 The secret key itself.
22047 @deftp {Data Type} knot-acl-configuration
22048 Data type representing an Access Control List (ACL) configuration.
22049 This type has the following parameters:
22052 @item @code{id} (default: @code{""})
22053 An identifier for ether configuration fields to refer to this key. IDs must be
22054 unique and must not be empty.
22056 @item @code{address} (default: @code{'()})
22057 An ordered list of IP addresses, network subnets, or network ranges represented
22058 with strings. The query must match one of them. Empty value means that
22059 address match is not required.
22061 @item @code{key} (default: @code{'()})
22062 An ordered list of references to keys represented with strings. The string
22063 must match a key ID defined in a @code{knot-key-configuration}. No key means
22064 that a key is not require to match that ACL.
22066 @item @code{action} (default: @code{'()})
22067 An ordered list of actions that are permitted or forbidden by this ACL. Possible
22068 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
22069 and @code{'update}.
22071 @item @code{deny?} (default: @code{#f})
22072 When true, the ACL defines restrictions. Listed actions are forbidden. When
22073 false, listed actions are allowed.
22078 @deftp {Data Type} zone-entry
22079 Data type representing a record entry in a zone file.
22080 This type has the following parameters:
22083 @item @code{name} (default: @code{"@@"})
22084 The name of the record. @code{"@@"} refers to the origin of the zone. Names
22085 are relative to the origin of the zone. For example, in the @code{example.org}
22086 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
22087 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
22088 refers to @code{ns.example.org}.
22090 @item @code{ttl} (default: @code{""})
22091 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
22093 @item @code{class} (default: @code{"IN"})
22094 The class of the record. Knot currently supports only @code{"IN"} and
22095 partially @code{"CH"}.
22097 @item @code{type} (default: @code{"A"})
22098 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
22099 address), NS (Name Server) and MX (Mail eXchange). Many other types are
22102 @item @code{data} (default: @code{""})
22103 The data contained in the record. For instance an IP address associated with
22104 an A record, or a domain name associated with an NS record. Remember that
22105 domain names are relative to the origin unless they end with a dot.
22110 @deftp {Data Type} zone-file
22111 Data type representing the content of a zone file.
22112 This type has the following parameters:
22115 @item @code{entries} (default: @code{'()})
22116 The list of entries. The SOA record is taken care of, so you don't need to
22117 put it in the list of entries. This list should probably contain an entry
22118 for your primary authoritative DNS server. Other than using a list of entries
22119 directly, you can use @code{define-zone-entries} to define a object containing
22120 the list of entries more easily, that you can later pass to the @code{entries}
22121 field of the @code{zone-file}.
22123 @item @code{origin} (default: @code{""})
22124 The name of your zone. This parameter cannot be empty.
22126 @item @code{ns} (default: @code{"ns"})
22127 The domain of your primary authoritative DNS server. The name is relative to
22128 the origin, unless it ends with a dot. It is mandatory that this primary
22129 DNS server corresponds to an NS record in the zone and that it is associated
22130 to an IP address in the list of entries.
22132 @item @code{mail} (default: @code{"hostmaster"})
22133 An email address people can contact you at, as the owner of the zone. This
22134 is translated as @code{<mail>@@<origin>}.
22136 @item @code{serial} (default: @code{1})
22137 The serial number of the zone. As this is used to keep track of changes by
22138 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
22139 Always increment it when you make a change in your zone.
22141 @item @code{refresh} (default: @code{(* 2 24 3600)})
22142 The frequency at which slaves will do a zone transfer. This value is a number
22143 of seconds. It can be computed by multiplications or with
22144 @code{(string->duration)}.
22146 @item @code{retry} (default: @code{(* 15 60)})
22147 The period after which a slave will retry to contact its master when it fails
22148 to do so a first time.
22150 @item @code{expiry} (default: @code{(* 14 24 3600)})
22151 Default TTL of records. Existing records are considered correct for at most
22152 this amount of time. After this period, resolvers will invalidate their cache
22153 and check again that it still exists.
22155 @item @code{nx} (default: @code{3600})
22156 Default TTL of inexistant records. This delay is usually short because you want
22157 your new domains to reach everyone quickly.
22162 @deftp {Data Type} knot-remote-configuration
22163 Data type representing a remote configuration.
22164 This type has the following parameters:
22167 @item @code{id} (default: @code{""})
22168 An identifier for other configuration fields to refer to this remote. IDs must
22169 be unique and must not be empty.
22171 @item @code{address} (default: @code{'()})
22172 An ordered list of destination IP addresses. Addresses are tried in sequence.
22173 An optional port can be given with the @@ separator. For instance:
22174 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
22176 @item @code{via} (default: @code{'()})
22177 An ordered list of source IP addresses. An empty list will have Knot choose
22178 an appropriate source IP. An optional port can be given with the @@ separator.
22179 The default is to choose at random.
22181 @item @code{key} (default: @code{#f})
22182 A reference to a key, that is a string containing the identifier of a key
22183 defined in a @code{knot-key-configuration} field.
22188 @deftp {Data Type} knot-keystore-configuration
22189 Data type representing a keystore to hold dnssec keys.
22190 This type has the following parameters:
22193 @item @code{id} (default: @code{""})
22194 The id of the keystore. It must not be empty.
22196 @item @code{backend} (default: @code{'pem})
22197 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
22199 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
22200 The configuration string of the backend. An example for the PKCS#11 is:
22201 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
22202 For the pem backend, the string represents a path in the file system.
22207 @deftp {Data Type} knot-policy-configuration
22208 Data type representing a dnssec policy. Knot DNS is able to automatically
22209 sign your zones. It can either generate and manage your keys automatically or
22210 use keys that you generate.
22212 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
22213 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
22214 zone. In order to be trusted, the KSK needs to be present in the parent zone
22215 (usually a top-level domain). If your registrar supports dnssec, you will
22216 have to send them your KSK's hash so they can add a DS record in their zone.
22217 This is not automated and need to be done each time you change your KSK.
22219 The policy also defines the lifetime of keys. Usually, ZSK can be changed
22220 easily and use weaker cryptographic functions (they use lower parameters) in
22221 order to sign records quickly, so they are changed often. The KSK however
22222 requires manual interaction with the registrar, so they are changed less often
22223 and use stronger parameters because they sign only one record.
22225 This type has the following parameters:
22228 @item @code{id} (default: @code{""})
22229 The id of the policy. It must not be empty.
22231 @item @code{keystore} (default: @code{"default"})
22232 A reference to a keystore, that is a string containing the identifier of a
22233 keystore defined in a @code{knot-keystore-configuration} field. The
22234 @code{"default"} identifier means the default keystore (a kasp database that
22235 was setup by this service).
22237 @item @code{manual?} (default: @code{#f})
22238 Whether the key management is manual or automatic.
22240 @item @code{single-type-signing?} (default: @code{#f})
22241 When @code{#t}, use the Single-Type Signing Scheme.
22243 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
22244 An algorithm of signing keys and issued signatures.
22246 @item @code{ksk-size} (default: @code{256})
22247 The length of the KSK. Note that this value is correct for the default
22248 algorithm, but would be unsecure for other algorithms.
22250 @item @code{zsk-size} (default: @code{256})
22251 The length of the ZSK. Note that this value is correct for the default
22252 algorithm, but would be unsecure for other algorithms.
22254 @item @code{dnskey-ttl} (default: @code{'default})
22255 The TTL value for DNSKEY records added into zone apex. The special
22256 @code{'default} value means same as the zone SOA TTL.
22258 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
22259 The period between ZSK publication and the next rollover initiation.
22261 @item @code{propagation-delay} (default: @code{(* 24 3600)})
22262 An extra delay added for each key rollover step. This value should be high
22263 enough to cover propagation of data from the master server to all slaves.
22265 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
22266 A validity period of newly issued signatures.
22268 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
22269 A period how long before a signature expiration the signature will be refreshed.
22271 @item @code{nsec3?} (default: @code{#f})
22272 When @code{#t}, NSEC3 will be used instead of NSEC.
22274 @item @code{nsec3-iterations} (default: @code{5})
22275 The number of additional times the hashing is performed.
22277 @item @code{nsec3-salt-length} (default: @code{8})
22278 The length of a salt field in octets, which is appended to the original owner
22279 name before hashing.
22281 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
22282 The validity period of newly issued salt field.
22287 @deftp {Data Type} knot-zone-configuration
22288 Data type representing a zone served by Knot.
22289 This type has the following parameters:
22292 @item @code{domain} (default: @code{""})
22293 The domain served by this configuration. It must not be empty.
22295 @item @code{file} (default: @code{""})
22296 The file where this zone is saved. This parameter is ignored by master zones.
22297 Empty means default location that depends on the domain name.
22299 @item @code{zone} (default: @code{(zone-file)})
22300 The content of the zone file. This parameter is ignored by slave zones. It
22301 must contain a zone-file record.
22303 @item @code{master} (default: @code{'()})
22304 A list of master remotes. When empty, this zone is a master. When set, this
22305 zone is a slave. This is a list of remotes identifiers.
22307 @item @code{ddns-master} (default: @code{#f})
22308 The main master. When empty, it defaults to the first master in the list of
22311 @item @code{notify} (default: @code{'()})
22312 A list of slave remote identifiers.
22314 @item @code{acl} (default: @code{'()})
22315 A list of acl identifiers.
22317 @item @code{semantic-checks?} (default: @code{#f})
22318 When set, this adds more semantic checks to the zone.
22320 @item @code{disable-any?} (default: @code{#f})
22321 When set, this forbids queries of the ANY type.
22323 @item @code{zonefile-sync} (default: @code{0})
22324 The delay between a modification in memory and on disk. 0 means immediate
22327 @item @code{zonefile-load} (default: @code{#f})
22328 The way the zone file contents are applied during zone load. Possible values
22332 @item @code{#f} for using the default value from Knot,
22333 @item @code{'none} for not using the zone file at all,
22334 @item @code{'difference} for computing the difference between already available
22335 contents and zone contents and applying it to the current zone contents,
22336 @item @code{'difference-no-serial} for the same as @code{'difference}, but
22337 ignoring the SOA serial in the zone file, while the server takes care of it
22339 @item @code{'whole} for loading zone contents from the zone file.
22342 @item @code{journal-content} (default: @code{#f})
22343 The way the journal is used to store zone and its changes. Possible values
22344 are @code{'none} to not use it at all, @code{'changes} to store changes and
22345 @code{'all} to store contents. @code{#f} does not set this option, so the
22346 default value from Knot is used.
22348 @item @code{max-journal-usage} (default: @code{#f})
22349 The maximum size for the journal on disk. @code{#f} does not set this option,
22350 so the default value from Knot is used.
22352 @item @code{max-journal-depth} (default: @code{#f})
22353 The maximum size of the history. @code{#f} does not set this option, so the
22354 default value from Knot is used.
22356 @item @code{max-zone-size} (default: @code{#f})
22357 The maximum size of the zone file. This limit is enforced for incoming
22358 transfer and updates. @code{#f} does not set this option, so the default
22359 value from Knot is used.
22361 @item @code{dnssec-policy} (default: @code{#f})
22362 A reference to a @code{knot-policy-configuration} record, or the special
22363 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
22366 @item @code{serial-policy} (default: @code{'increment})
22367 A policy between @code{'increment} and @code{'unixtime}.
22372 @deftp {Data Type} knot-configuration
22373 Data type representing the Knot configuration.
22374 This type has the following parameters:
22377 @item @code{knot} (default: @code{knot})
22380 @item @code{run-directory} (default: @code{"/var/run/knot"})
22381 The run directory. This directory will be used for pid file and sockets.
22383 @item @code{includes} (default: @code{'()})
22384 A list of strings or file-like objects denoting other files that must be
22385 included at the top of the configuration file.
22387 @cindex secrets, Knot service
22388 This can be used to manage secrets out-of-band. For example, secret
22389 keys may be stored in an out-of-band file not managed by Guix, and
22390 thus not visible in @file{/gnu/store}---e.g., you could store secret
22391 key configuration in @file{/etc/knot/secrets.conf} and add this file
22392 to the @code{includes} list.
22394 One can generate a secret tsig key (for nsupdate and zone transfers with the
22395 keymgr command from the knot package. Note that the package is not automatically
22396 installed by the service. The following example shows how to generate a new
22400 keymgr -t mysecret > /etc/knot/secrets.conf
22401 chmod 600 /etc/knot/secrets.conf
22404 Also note that the generated key will be named @var{mysecret}, so it is the
22405 name that needs to be used in the @var{key} field of the
22406 @code{knot-acl-configuration} record and in other places that need to refer
22409 It can also be used to add configuration not supported by this interface.
22411 @item @code{listen-v4} (default: @code{"0.0.0.0"})
22412 An ip address on which to listen.
22414 @item @code{listen-v6} (default: @code{"::"})
22415 An ip address on which to listen.
22417 @item @code{listen-port} (default: @code{53})
22418 A port on which to listen.
22420 @item @code{keys} (default: @code{'()})
22421 The list of knot-key-configuration used by this configuration.
22423 @item @code{acls} (default: @code{'()})
22424 The list of knot-acl-configuration used by this configuration.
22426 @item @code{remotes} (default: @code{'()})
22427 The list of knot-remote-configuration used by this configuration.
22429 @item @code{zones} (default: @code{'()})
22430 The list of knot-zone-configuration used by this configuration.
22435 @subsubheading Knot Resolver Service
22437 @deffn {Scheme Variable} knot-resolver-service-type
22438 This this the type of the knot resolver service, whose value should be
22439 an @code{knot-resolver-configuration} object as in this example:
22442 (service knot-resolver-service-type
22443 (knot-resolver-configuration
22444 (kresd-config-file (plain-file "kresd.conf" "
22445 net.listen('192.168.0.1', 5353)
22446 user('knot-resolver', 'knot-resolver')
22447 modules = @{ 'hints > iterate', 'stats', 'predict' @}
22448 cache.size = 100 * MB
22452 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
22455 @deftp {Data Type} knot-resolver-configuration
22456 Data type representing the configuration of knot-resolver.
22459 @item @code{package} (default: @var{knot-resolver})
22460 Package object of the knot DNS resolver.
22462 @item @code{kresd-config-file} (default: %kresd.conf)
22463 File-like object of the kresd configuration file to use, by default it
22464 will listen on @code{127.0.0.1} and @code{::1}.
22466 @item @code{garbage-collection-interval} (default: 1000)
22467 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
22473 @subsubheading Dnsmasq Service
22475 @deffn {Scheme Variable} dnsmasq-service-type
22476 This is the type of the dnsmasq service, whose value should be an
22477 @code{dnsmasq-configuration} object as in this example:
22480 (service dnsmasq-service-type
22481 (dnsmasq-configuration
22483 (servers '("192.168.1.1"))))
22487 @deftp {Data Type} dnsmasq-configuration
22488 Data type representing the configuration of dnsmasq.
22491 @item @code{package} (default: @var{dnsmasq})
22492 Package object of the dnsmasq server.
22494 @item @code{no-hosts?} (default: @code{#f})
22495 When true, don't read the hostnames in /etc/hosts.
22497 @item @code{port} (default: @code{53})
22498 The port to listen on. Setting this to zero completely disables DNS
22499 responses, leaving only DHCP and/or TFTP functions.
22501 @item @code{local-service?} (default: @code{#t})
22502 Accept DNS queries only from hosts whose address is on a local subnet,
22503 ie a subnet for which an interface exists on the server.
22505 @item @code{listen-addresses} (default: @code{'()})
22506 Listen on the given IP addresses.
22508 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
22509 The file to read the IP address of the upstream nameservers from.
22511 @item @code{no-resolv?} (default: @code{#f})
22512 When true, don't read @var{resolv-file}.
22514 @item @code{servers} (default: @code{'()})
22515 Specify IP address of upstream servers directly.
22517 @item @code{addresses} (default: @code{'()})
22518 For each entry, specify an IP address to return for any host in the
22519 given domains. Queries in the domains are never forwarded and always
22520 replied to with the specified IP address.
22522 This is useful for redirecting hosts locally, for example:
22525 (service dnsmasq-service-type
22526 (dnsmasq-configuration
22528 '(; Redirect to a local web-server.
22529 "/example.org/127.0.0.1"
22530 ; Redirect subdomain to a specific IP.
22531 "/subdomain.example.org/192.168.1.42"))))
22534 Note that rules in @file{/etc/hosts} take precedence over this.
22536 @item @code{cache-size} (default: @code{150})
22537 Set the size of dnsmasq's cache. Setting the cache size to zero
22540 @item @code{negative-cache?} (default: @code{#t})
22541 When false, disable negative caching.
22546 @subsubheading ddclient Service
22549 The ddclient service described below runs the ddclient daemon, which takes
22550 care of automatically updating DNS entries for service providers such as
22551 @uref{https://dyn.com/dns/, Dyn}.
22553 The following example show instantiates the service with its default
22557 (service ddclient-service-type)
22560 Note that ddclient needs to access credentials that are stored in a
22561 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
22562 @code{secret-file} below). You are expected to create this file manually, in
22563 an ``out-of-band'' fashion (you @emph{could} make this file part of the
22564 service configuration, for instance by using @code{plain-file}, but it will be
22565 world-readable @i{via} @file{/gnu/store}). See the examples in the
22566 @file{share/ddclient} directory of the @code{ddclient} package.
22568 @c %start of fragment
22570 Available @code{ddclient-configuration} fields are:
22572 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
22573 The ddclient package.
22577 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
22578 The period after which ddclient will retry to check IP and domain name.
22580 Defaults to @samp{300}.
22584 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
22585 Use syslog for the output.
22587 Defaults to @samp{#t}.
22591 @deftypevr {@code{ddclient-configuration} parameter} string mail
22594 Defaults to @samp{"root"}.
22598 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
22599 Mail failed update to user.
22601 Defaults to @samp{"root"}.
22605 @deftypevr {@code{ddclient-configuration} parameter} string pid
22606 The ddclient PID file.
22608 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
22612 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
22613 Enable SSL support.
22615 Defaults to @samp{#t}.
22619 @deftypevr {@code{ddclient-configuration} parameter} string user
22620 Specifies the user name or ID that is used when running ddclient
22623 Defaults to @samp{"ddclient"}.
22627 @deftypevr {@code{ddclient-configuration} parameter} string group
22628 Group of the user who will run the ddclient program.
22630 Defaults to @samp{"ddclient"}.
22634 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
22635 Secret file which will be appended to @file{ddclient.conf} file. This
22636 file contains credentials for use by ddclient. You are expected to
22637 create it manually.
22639 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
22643 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
22644 Extra options will be appended to @file{ddclient.conf} file.
22646 Defaults to @samp{()}.
22651 @c %end of fragment
22655 @subsection VPN Services
22656 @cindex VPN (virtual private network)
22657 @cindex virtual private network (VPN)
22659 The @code{(gnu services vpn)} module provides services related to
22660 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
22661 your machine to connect to a VPN, and a @emph{server} service for your machine
22662 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
22664 @deffn {Scheme Procedure} openvpn-client-service @
22665 [#:config (openvpn-client-configuration)]
22667 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
22670 @deffn {Scheme Procedure} openvpn-server-service @
22671 [#:config (openvpn-server-configuration)]
22673 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
22675 Both can be run simultaneously.
22678 @c %automatically generated documentation
22680 Available @code{openvpn-client-configuration} fields are:
22682 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
22683 The OpenVPN package.
22687 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
22688 The OpenVPN pid file.
22690 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
22694 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
22695 The protocol (UDP or TCP) used to open a channel between clients and
22698 Defaults to @samp{udp}.
22702 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
22703 The device type used to represent the VPN connection.
22705 Defaults to @samp{tun}.
22709 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
22710 The certificate authority to check connections against.
22712 Defaults to @samp{"/etc/openvpn/ca.crt"}.
22716 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
22717 The certificate of the machine the daemon is running on. It should be
22718 signed by the authority given in @code{ca}.
22720 Defaults to @samp{"/etc/openvpn/client.crt"}.
22724 @deftypevr {@code{openvpn-client-configuration} parameter} string key
22725 The key of the machine the daemon is running on. It must be the key whose
22726 certificate is @code{cert}.
22728 Defaults to @samp{"/etc/openvpn/client.key"}.
22732 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
22733 Whether to use the lzo compression algorithm.
22735 Defaults to @samp{#t}.
22739 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
22740 Don't re-read key files across SIGUSR1 or --ping-restart.
22742 Defaults to @samp{#t}.
22746 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
22747 Don't close and reopen TUN/TAP device or run up/down scripts across
22748 SIGUSR1 or --ping-restart restarts.
22750 Defaults to @samp{#t}.
22754 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
22755 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22756 poll/epoll/select prior to the write operation.
22758 Defaults to @samp{#f}.
22761 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
22764 Defaults to @samp{3}.
22768 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
22769 Add an additional layer of HMAC authentication on top of the TLS control
22770 channel to protect against DoS attacks.
22772 Defaults to @samp{#f}.
22776 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
22777 Authenticate with server using username/password. The option is a file
22778 containing username/password on 2 lines. Do not use a file-like object as it
22779 would be added to the store and readable by any user.
22781 Defaults to @samp{'disabled}.
22784 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
22785 Whether to check the server certificate has server usage extension.
22787 Defaults to @samp{#t}.
22791 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
22792 Bind to a specific local port number.
22794 Defaults to @samp{#f}.
22798 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
22799 Retry resolving server address.
22801 Defaults to @samp{#t}.
22805 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
22806 A list of remote servers to connect to.
22808 Defaults to @samp{()}.
22810 Available @code{openvpn-remote-configuration} fields are:
22812 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
22815 Defaults to @samp{"my-server"}.
22819 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
22820 Port number the server listens to.
22822 Defaults to @samp{1194}.
22827 @c %end of automatic openvpn-client documentation
22829 @c %automatically generated documentation
22831 Available @code{openvpn-server-configuration} fields are:
22833 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
22834 The OpenVPN package.
22838 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
22839 The OpenVPN pid file.
22841 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
22845 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
22846 The protocol (UDP or TCP) used to open a channel between clients and
22849 Defaults to @samp{udp}.
22853 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
22854 The device type used to represent the VPN connection.
22856 Defaults to @samp{tun}.
22860 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
22861 The certificate authority to check connections against.
22863 Defaults to @samp{"/etc/openvpn/ca.crt"}.
22867 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
22868 The certificate of the machine the daemon is running on. It should be
22869 signed by the authority given in @code{ca}.
22871 Defaults to @samp{"/etc/openvpn/client.crt"}.
22875 @deftypevr {@code{openvpn-server-configuration} parameter} string key
22876 The key of the machine the daemon is running on. It must be the key whose
22877 certificate is @code{cert}.
22879 Defaults to @samp{"/etc/openvpn/client.key"}.
22883 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
22884 Whether to use the lzo compression algorithm.
22886 Defaults to @samp{#t}.
22890 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
22891 Don't re-read key files across SIGUSR1 or --ping-restart.
22893 Defaults to @samp{#t}.
22897 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
22898 Don't close and reopen TUN/TAP device or run up/down scripts across
22899 SIGUSR1 or --ping-restart restarts.
22901 Defaults to @samp{#t}.
22905 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
22906 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22907 poll/epoll/select prior to the write operation.
22909 Defaults to @samp{#f}.
22912 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
22915 Defaults to @samp{3}.
22919 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
22920 Add an additional layer of HMAC authentication on top of the TLS control
22921 channel to protect against DoS attacks.
22923 Defaults to @samp{#f}.
22927 @deftypevr {@code{openvpn-server-configuration} parameter} number port
22928 Specifies the port number on which the server listens.
22930 Defaults to @samp{1194}.
22934 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
22935 An ip and mask specifying the subnet inside the virtual network.
22937 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
22941 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
22942 A CIDR notation specifying the IPv6 subnet inside the virtual network.
22944 Defaults to @samp{#f}.
22948 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
22949 The Diffie-Hellman parameters file.
22951 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
22955 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
22956 The file that records client IPs.
22958 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
22962 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
22963 When true, the server will act as a gateway for its clients.
22965 Defaults to @samp{#f}.
22969 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
22970 When true, clients are allowed to talk to each other inside the VPN.
22972 Defaults to @samp{#f}.
22976 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
22977 Causes ping-like messages to be sent back and forth over the link so
22978 that each side knows when the other side has gone down. @code{keepalive}
22979 requires a pair. The first element is the period of the ping sending,
22980 and the second element is the timeout before considering the other side
22985 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
22986 The maximum number of clients.
22988 Defaults to @samp{100}.
22992 @deftypevr {@code{openvpn-server-configuration} parameter} string status
22993 The status file. This file shows a small report on current connection.
22994 It is truncated and rewritten every minute.
22996 Defaults to @samp{"/var/run/openvpn/status"}.
23000 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
23001 The list of configuration for some clients.
23003 Defaults to @samp{()}.
23005 Available @code{openvpn-ccd-configuration} fields are:
23007 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
23010 Defaults to @samp{"client"}.
23014 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
23017 Defaults to @samp{#f}.
23021 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
23024 Defaults to @samp{#f}.
23031 @c %end of automatic openvpn-server documentation
23034 @node Network File System
23035 @subsection Network File System
23038 The @code{(gnu services nfs)} module provides the following services,
23039 which are most commonly used in relation to mounting or exporting
23040 directory trees as @dfn{network file systems} (NFS).
23042 While it is possible to use the individual components that together make
23043 up a Network File System service, we recommended to configure an NFS
23044 server with the @code{nfs-service-type}.
23046 @subsubheading NFS Service
23047 @cindex NFS, server
23049 The NFS service takes care of setting up all NFS component services,
23050 kernel configuration file systems, and installs configuration files in
23051 the locations that NFS expects.
23053 @defvr {Scheme Variable} nfs-service-type
23054 A service type for a complete NFS server.
23057 @deftp {Data Type} nfs-configuration
23058 This data type represents the configuration of the NFS service and all
23061 It has the following parameters:
23063 @item @code{nfs-utils} (default: @code{nfs-utils})
23064 The nfs-utils package to use.
23066 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
23067 If a list of string values is provided, the @command{rpc.nfsd} daemon
23068 will be limited to supporting the given versions of the NFS protocol.
23070 @item @code{exports} (default: @code{'()})
23071 This is a list of directories the NFS server should export. Each entry
23072 is a list consisting of two elements: a directory name and a string
23073 containing all options. This is an example in which the directory
23074 @file{/export} is served to all NFS clients as a read-only share:
23080 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
23083 @item @code{rpcmountd-port} (default: @code{#f})
23084 The network port that the @command{rpc.mountd} daemon should use.
23086 @item @code{rpcstatd-port} (default: @code{#f})
23087 The network port that the @command{rpc.statd} daemon should use.
23089 @item @code{rpcbind} (default: @code{rpcbind})
23090 The rpcbind package to use.
23092 @item @code{idmap-domain} (default: @code{"localdomain"})
23093 The local NFSv4 domain name.
23095 @item @code{nfsd-port} (default: @code{2049})
23096 The network port that the @command{nfsd} daemon should use.
23098 @item @code{nfsd-threads} (default: @code{8})
23099 The number of threads used by the @command{nfsd} daemon.
23101 @item @code{nfsd-tcp?} (default: @code{#t})
23102 Whether the @command{nfsd} daemon should listen on a TCP socket.
23104 @item @code{nfsd-udp?} (default: @code{#f})
23105 Whether the @command{nfsd} daemon should listen on a UDP socket.
23107 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
23108 The directory where the pipefs file system is mounted.
23110 @item @code{debug} (default: @code{'()"})
23111 A list of subsystems for which debugging output should be enabled. This
23112 is a list of symbols. Any of these symbols are valid: @code{nfsd},
23113 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
23117 If you don't need a complete NFS service or prefer to build it yourself
23118 you can use the individual component services that are documented below.
23120 @subsubheading RPC Bind Service
23123 The RPC Bind service provides a facility to map program numbers into
23124 universal addresses.
23125 Many NFS related services use this facility. Hence it is automatically
23126 started when a dependent service starts.
23128 @defvr {Scheme Variable} rpcbind-service-type
23129 A service type for the RPC portmapper daemon.
23133 @deftp {Data Type} rpcbind-configuration
23134 Data type representing the configuration of the RPC Bind Service.
23135 This type has the following parameters:
23137 @item @code{rpcbind} (default: @code{rpcbind})
23138 The rpcbind package to use.
23140 @item @code{warm-start?} (default: @code{#t})
23141 If this parameter is @code{#t}, then the daemon will read a
23142 state file on startup thus reloading state information saved by a previous
23148 @subsubheading Pipefs Pseudo File System
23152 The pipefs file system is used to transfer NFS related data
23153 between the kernel and user space programs.
23155 @defvr {Scheme Variable} pipefs-service-type
23156 A service type for the pipefs pseudo file system.
23159 @deftp {Data Type} pipefs-configuration
23160 Data type representing the configuration of the pipefs pseudo file system service.
23161 This type has the following parameters:
23163 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
23164 The directory to which the file system is to be attached.
23169 @subsubheading GSS Daemon Service
23172 @cindex global security system
23174 The @dfn{global security system} (GSS) daemon provides strong security for RPC
23176 Before exchanging RPC requests an RPC client must establish a security
23177 context. Typically this is done using the Kerberos command @command{kinit}
23178 or automatically at login time using PAM services (@pxref{Kerberos Services}).
23180 @defvr {Scheme Variable} gss-service-type
23181 A service type for the Global Security System (GSS) daemon.
23184 @deftp {Data Type} gss-configuration
23185 Data type representing the configuration of the GSS daemon service.
23186 This type has the following parameters:
23188 @item @code{nfs-utils} (default: @code{nfs-utils})
23189 The package in which the @command{rpc.gssd} command is to be found.
23191 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
23192 The directory where the pipefs file system is mounted.
23198 @subsubheading IDMAP Daemon Service
23200 @cindex name mapper
23202 The idmap daemon service provides mapping between user IDs and user names.
23203 Typically it is required in order to access file systems mounted via NFSv4.
23205 @defvr {Scheme Variable} idmap-service-type
23206 A service type for the Identity Mapper (IDMAP) daemon.
23209 @deftp {Data Type} idmap-configuration
23210 Data type representing the configuration of the IDMAP daemon service.
23211 This type has the following parameters:
23213 @item @code{nfs-utils} (default: @code{nfs-utils})
23214 The package in which the @command{rpc.idmapd} command is to be found.
23216 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
23217 The directory where the pipefs file system is mounted.
23219 @item @code{domain} (default: @code{#f})
23220 The local NFSv4 domain name.
23221 This must be a string or @code{#f}.
23222 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
23224 @item @code{verbosity} (default: @code{0})
23225 The verbosity level of the daemon.
23230 @node Continuous Integration
23231 @subsection Continuous Integration
23233 @cindex continuous integration
23234 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
23235 continuous integration tool for Guix. It can be used both for development and
23236 for providing substitutes to others (@pxref{Substitutes}).
23238 The @code{(gnu services cuirass)} module provides the following service.
23240 @defvr {Scheme Procedure} cuirass-service-type
23241 The type of the Cuirass service. Its value must be a
23242 @code{cuirass-configuration} object, as described below.
23245 To add build jobs, you have to set the @code{specifications} field of the
23246 configuration. Here is an example of a service that polls the Guix repository
23247 and builds the packages from a manifest. Some of the packages are defined in
23248 the @code{"custom-packages"} input, which is the equivalent of
23249 @env{GUIX_PACKAGE_PATH}.
23252 (define %cuirass-specs
23254 '((#:name . "my-manifest")
23255 (#:load-path-inputs . ("guix"))
23256 (#:package-path-inputs . ("custom-packages"))
23257 (#:proc-input . "guix")
23258 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
23259 (#:proc . cuirass-jobs)
23260 (#:proc-args . ((subset . "manifests")
23261 (systems . ("x86_64-linux"))
23262 (manifests . (("config" . "guix/manifest.scm")))))
23263 (#:inputs . (((#:name . "guix")
23264 (#:url . "git://git.savannah.gnu.org/guix.git")
23265 (#:load-path . ".")
23266 (#:branch . "master")
23267 (#:no-compile? . #t))
23268 ((#:name . "config")
23269 (#:url . "https://git.example.org/config.git")
23270 (#:load-path . ".")
23271 (#:branch . "master")
23272 (#:no-compile? . #t))
23273 ((#:name . "custom-packages")
23274 (#:url . "https://git.example.org/custom-packages.git")
23275 (#:load-path . ".")
23276 (#:branch . "master")
23277 (#:no-compile? . #t)))))))
23279 (service cuirass-service-type
23280 (cuirass-configuration
23281 (specifications %cuirass-specs)))
23284 While information related to build jobs is located directly in the
23285 specifications, global settings for the @command{cuirass} process are
23286 accessible in other @code{cuirass-configuration} fields.
23288 @deftp {Data Type} cuirass-configuration
23289 Data type representing the configuration of Cuirass.
23292 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
23293 Location of the log file.
23295 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
23296 Location of the log file used by the web interface.
23298 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
23299 Location of the repository cache.
23301 @item @code{user} (default: @code{"cuirass"})
23302 Owner of the @code{cuirass} process.
23304 @item @code{group} (default: @code{"cuirass"})
23305 Owner's group of the @code{cuirass} process.
23307 @item @code{interval} (default: @code{60})
23308 Number of seconds between the poll of the repositories followed by the
23311 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
23312 Location of sqlite database which contains the build results and previously
23313 added specifications.
23315 @item @code{ttl} (default: @code{(* 30 24 3600)})
23316 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
23317 are registered for build results. This means that build results are protected
23318 from garbage collection for at least @var{ttl} seconds.
23320 @item @code{port} (default: @code{8081})
23321 Port number used by the HTTP server.
23323 @item @code{host} (default: @code{"localhost"})
23324 Listen on the network interface for @var{host}. The default is to
23325 accept connections from localhost.
23327 @item @code{specifications} (default: @code{#~'()})
23328 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
23329 where a specification is an association list
23330 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
23331 keys are keywords (@code{#:keyword-example}) as shown in the example
23334 @item @code{use-substitutes?} (default: @code{#f})
23335 This allows using substitutes to avoid building every dependencies of a job
23338 @item @code{one-shot?} (default: @code{#f})
23339 Only evaluate specifications and build derivations once.
23341 @item @code{fallback?} (default: @code{#f})
23342 When substituting a pre-built binary fails, fall back to building
23345 @item @code{extra-options} (default: @code{'()})
23346 Extra options to pass when running the Cuirass processes.
23348 @item @code{cuirass} (default: @code{cuirass})
23349 The Cuirass package to use.
23353 @node Power Management Services
23354 @subsection Power Management Services
23357 @cindex power management with TLP
23358 @subsubheading TLP daemon
23360 The @code{(gnu services pm)} module provides a Guix service definition
23361 for the Linux power management tool TLP.
23363 TLP enables various powersaving modes in userspace and kernel.
23364 Contrary to @code{upower-service}, it is not a passive,
23365 monitoring tool, as it will apply custom settings each time a new power
23366 source is detected. More information can be found at
23367 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
23369 @deffn {Scheme Variable} tlp-service-type
23370 The service type for the TLP tool. Its value should be a valid
23371 TLP configuration (see below). To use the default settings, simply
23374 (service tlp-service-type)
23378 By default TLP does not need much configuration but most TLP parameters
23379 can be tweaked using @code{tlp-configuration}.
23381 Each parameter definition is preceded by its type; for example,
23382 @samp{boolean foo} indicates that the @code{foo} parameter
23383 should be specified as a boolean. Types starting with
23384 @code{maybe-} denote parameters that won't show up in TLP config file
23385 when their value is @code{'disabled}.
23387 @c The following documentation was initially generated by
23388 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
23389 @c documentation is better, so we shouldn't hesitate to edit below as
23390 @c needed. However if the change you want to make to this documentation
23391 @c can be done in an automated way, it's probably easier to change
23392 @c (generate-documentation) than to make it below and have to deal with
23393 @c the churn as TLP updates.
23395 Available @code{tlp-configuration} fields are:
23397 @deftypevr {@code{tlp-configuration} parameter} package tlp
23402 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
23403 Set to true if you wish to enable TLP.
23405 Defaults to @samp{#t}.
23409 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
23410 Default mode when no power supply can be detected. Alternatives are AC
23413 Defaults to @samp{"AC"}.
23417 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
23418 Number of seconds Linux kernel has to wait after the disk goes idle,
23419 before syncing on AC.
23421 Defaults to @samp{0}.
23425 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
23426 Same as @code{disk-idle-ac} but on BAT mode.
23428 Defaults to @samp{2}.
23432 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
23433 Dirty pages flushing periodicity, expressed in seconds.
23435 Defaults to @samp{15}.
23439 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
23440 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
23442 Defaults to @samp{60}.
23446 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
23447 CPU frequency scaling governor on AC mode. With intel_pstate driver,
23448 alternatives are powersave and performance. With acpi-cpufreq driver,
23449 alternatives are ondemand, powersave, performance and conservative.
23451 Defaults to @samp{disabled}.
23455 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
23456 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
23458 Defaults to @samp{disabled}.
23462 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
23463 Set the min available frequency for the scaling governor on AC.
23465 Defaults to @samp{disabled}.
23469 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
23470 Set the max available frequency for the scaling governor on AC.
23472 Defaults to @samp{disabled}.
23476 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
23477 Set the min available frequency for the scaling governor on BAT.
23479 Defaults to @samp{disabled}.
23483 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
23484 Set the max available frequency for the scaling governor on BAT.
23486 Defaults to @samp{disabled}.
23490 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
23491 Limit the min P-state to control the power dissipation of the CPU, in AC
23492 mode. Values are stated as a percentage of the available performance.
23494 Defaults to @samp{disabled}.
23498 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
23499 Limit the max P-state to control the power dissipation of the CPU, in AC
23500 mode. Values are stated as a percentage of the available performance.
23502 Defaults to @samp{disabled}.
23506 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
23507 Same as @code{cpu-min-perf-on-ac} on BAT mode.
23509 Defaults to @samp{disabled}.
23513 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
23514 Same as @code{cpu-max-perf-on-ac} on BAT mode.
23516 Defaults to @samp{disabled}.
23520 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
23521 Enable CPU turbo boost feature on AC mode.
23523 Defaults to @samp{disabled}.
23527 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
23528 Same as @code{cpu-boost-on-ac?} on BAT mode.
23530 Defaults to @samp{disabled}.
23534 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
23535 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
23536 used under light load conditions.
23538 Defaults to @samp{#f}.
23542 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
23543 Same as @code{sched-powersave-on-ac?} but on BAT mode.
23545 Defaults to @samp{#t}.
23549 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
23550 Enable Linux kernel NMI watchdog.
23552 Defaults to @samp{#f}.
23556 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
23557 For Linux kernels with PHC patch applied, change CPU voltages. An
23558 example value would be @samp{"F:V F:V F:V F:V"}.
23560 Defaults to @samp{disabled}.
23564 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
23565 Set CPU performance versus energy saving policy on AC. Alternatives are
23566 performance, normal, powersave.
23568 Defaults to @samp{"performance"}.
23572 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
23573 Same as @code{energy-perf-policy-ac} but on BAT mode.
23575 Defaults to @samp{"powersave"}.
23579 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
23584 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
23585 Hard disk advanced power management level.
23589 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
23590 Same as @code{disk-apm-bat} but on BAT mode.
23594 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
23595 Hard disk spin down timeout. One value has to be specified for each
23596 declared hard disk.
23598 Defaults to @samp{disabled}.
23602 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
23603 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
23605 Defaults to @samp{disabled}.
23609 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
23610 Select IO scheduler for disk devices. One value has to be specified for
23611 each declared hard disk. Example alternatives are cfq, deadline and
23614 Defaults to @samp{disabled}.
23618 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
23619 SATA aggressive link power management (ALPM) level. Alternatives are
23620 min_power, medium_power, max_performance.
23622 Defaults to @samp{"max_performance"}.
23626 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
23627 Same as @code{sata-linkpwr-ac} but on BAT mode.
23629 Defaults to @samp{"min_power"}.
23633 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
23634 Exclude specified SATA host devices for link power management.
23636 Defaults to @samp{disabled}.
23640 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
23641 Enable Runtime Power Management for AHCI controller and disks on AC
23644 Defaults to @samp{disabled}.
23648 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
23649 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
23651 Defaults to @samp{disabled}.
23655 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
23656 Seconds of inactivity before disk is suspended.
23658 Defaults to @samp{15}.
23662 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
23663 PCI Express Active State Power Management level. Alternatives are
23664 default, performance, powersave.
23666 Defaults to @samp{"performance"}.
23670 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
23671 Same as @code{pcie-aspm-ac} but on BAT mode.
23673 Defaults to @samp{"powersave"}.
23677 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
23678 Radeon graphics clock speed level. Alternatives are low, mid, high,
23681 Defaults to @samp{"high"}.
23685 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
23686 Same as @code{radeon-power-ac} but on BAT mode.
23688 Defaults to @samp{"low"}.
23692 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
23693 Radeon dynamic power management method (DPM). Alternatives are battery,
23696 Defaults to @samp{"performance"}.
23700 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
23701 Same as @code{radeon-dpm-state-ac} but on BAT mode.
23703 Defaults to @samp{"battery"}.
23707 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
23708 Radeon DPM performance level. Alternatives are auto, low, high.
23710 Defaults to @samp{"auto"}.
23714 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
23715 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
23717 Defaults to @samp{"auto"}.
23721 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
23722 Wifi power saving mode.
23724 Defaults to @samp{#f}.
23728 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
23729 Same as @code{wifi-power-ac?} but on BAT mode.
23731 Defaults to @samp{#t}.
23735 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
23736 Disable wake on LAN.
23738 Defaults to @samp{#t}.
23742 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
23743 Timeout duration in seconds before activating audio power saving on
23744 Intel HDA and AC97 devices. A value of 0 disables power saving.
23746 Defaults to @samp{0}.
23750 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
23751 Same as @code{sound-powersave-ac} but on BAT mode.
23753 Defaults to @samp{1}.
23757 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
23758 Disable controller in powersaving mode on Intel HDA devices.
23760 Defaults to @samp{#t}.
23764 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
23765 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
23766 powered on again by releasing (and reinserting) the eject lever or by
23767 pressing the disc eject button on newer models.
23769 Defaults to @samp{#f}.
23773 @deftypevr {@code{tlp-configuration} parameter} string bay-device
23774 Name of the optical drive device to power off.
23776 Defaults to @samp{"sr0"}.
23780 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
23781 Runtime Power Management for PCI(e) bus devices. Alternatives are on
23784 Defaults to @samp{"on"}.
23788 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
23789 Same as @code{runtime-pm-ac} but on BAT mode.
23791 Defaults to @samp{"auto"}.
23795 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
23796 Runtime Power Management for all PCI(e) bus devices, except blacklisted
23799 Defaults to @samp{#t}.
23803 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
23804 Exclude specified PCI(e) device addresses from Runtime Power Management.
23806 Defaults to @samp{disabled}.
23810 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
23811 Exclude PCI(e) devices assigned to the specified drivers from Runtime
23816 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
23817 Enable USB autosuspend feature.
23819 Defaults to @samp{#t}.
23823 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
23824 Exclude specified devices from USB autosuspend.
23826 Defaults to @samp{disabled}.
23830 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
23831 Exclude WWAN devices from USB autosuspend.
23833 Defaults to @samp{#t}.
23837 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
23838 Include specified devices into USB autosuspend, even if they are already
23839 excluded by the driver or via @code{usb-blacklist-wwan?}.
23841 Defaults to @samp{disabled}.
23845 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
23846 Enable USB autosuspend before shutdown.
23848 Defaults to @samp{disabled}.
23852 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
23853 Restore radio device state (bluetooth, wifi, wwan) from previous
23854 shutdown on system startup.
23856 Defaults to @samp{#f}.
23861 @cindex CPU frequency scaling with thermald
23862 @subsubheading Thermald daemon
23864 The @code{(gnu services pm)} module provides an interface to
23865 thermald, a CPU frequency scaling service which helps prevent overheating.
23867 @defvr {Scheme Variable} thermald-service-type
23868 This is the service type for
23869 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
23870 Thermal Daemon, which is responsible for controlling the thermal state
23871 of processors and preventing overheating.
23874 @deftp {Data Type} thermald-configuration
23875 Data type representing the configuration of @code{thermald-service-type}.
23878 @item @code{ignore-cpuid-check?} (default: @code{#f})
23879 Ignore cpuid check for supported CPU models.
23881 @item @code{thermald} (default: @var{thermald})
23882 Package object of thermald.
23887 @node Audio Services
23888 @subsection Audio Services
23890 The @code{(gnu services audio)} module provides a service to start MPD
23891 (the Music Player Daemon).
23894 @subsubheading Music Player Daemon
23896 The Music Player Daemon (MPD) is a service that can play music while
23897 being controlled from the local machine or over the network by a variety
23900 The following example shows how one might run @code{mpd} as user
23901 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
23904 (service mpd-service-type
23910 @defvr {Scheme Variable} mpd-service-type
23911 The service type for @command{mpd}
23914 @deftp {Data Type} mpd-configuration
23915 Data type representing the configuration of @command{mpd}.
23918 @item @code{user} (default: @code{"mpd"})
23919 The user to run mpd as.
23921 @item @code{music-dir} (default: @code{"~/Music"})
23922 The directory to scan for music files.
23924 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
23925 The directory to store playlists.
23927 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
23928 The location of the music database.
23930 @item @code{state-file} (default: @code{"~/.mpd/state"})
23931 The location of the file that stores current MPD's state.
23933 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
23934 The location of the sticker database.
23936 @item @code{port} (default: @code{"6600"})
23937 The port to run mpd on.
23939 @item @code{address} (default: @code{"any"})
23940 The address that mpd will bind to. To use a Unix domain socket,
23941 an absolute path can be specified here.
23943 @item @code{outputs} (default: @code{"(list (mpd-output))"})
23944 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
23949 @deftp {Data Type} mpd-output
23950 Data type representing an @command{mpd} audio output.
23953 @item @code{name} (default: @code{"MPD"})
23954 The name of the audio output.
23956 @item @code{type} (default: @code{"pulse"})
23957 The type of audio output.
23959 @item @code{enabled?} (default: @code{#t})
23960 Specifies whether this audio output is enabled when MPD is started. By
23961 default, all audio outputs are enabled. This is just the default
23962 setting when there is no state file; with a state file, the previous
23965 @item @code{tags?} (default: @code{#t})
23966 If set to @code{#f}, then MPD will not send tags to this output. This
23967 is only useful for output plugins that can receive tags, for example the
23968 @code{httpd} output plugin.
23970 @item @code{always-on?} (default: @code{#f})
23971 If set to @code{#t}, then MPD attempts to keep this audio output always
23972 open. This may be useful for streaming servers, when you don’t want to
23973 disconnect all listeners even when playback is accidentally stopped.
23975 @item @code{mixer-type}
23976 This field accepts a symbol that specifies which mixer should be used
23977 for this audio output: the @code{hardware} mixer, the @code{software}
23978 mixer, the @code{null} mixer (allows setting the volume, but with no
23979 effect; this can be used as a trick to implement an external mixer
23980 External Mixer) or no mixer (@code{none}).
23982 @item @code{extra-options} (default: @code{'()"})
23983 An association list of option symbols to string values to be appended to
23984 the audio output configuration.
23989 The following example shows a configuration of @code{mpd} that provides
23990 an HTTP audio streaming output.
23993 (service mpd-service-type
24001 `((encoder . "vorbis")
24002 (port . "8080"))))))))
24006 @node Virtualization Services
24007 @subsection Virtualization services
24009 The @code{(gnu services virtualization)} module provides services for
24010 the libvirt and virtlog daemons, as well as other virtualization-related
24013 @subsubheading Libvirt daemon
24014 @code{libvirtd} is the server side daemon component of the libvirt
24015 virtualization management system. This daemon runs on host servers
24016 and performs required management tasks for virtualized guests.
24018 @deffn {Scheme Variable} libvirt-service-type
24019 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
24020 Its value must be a @code{libvirt-configuration}.
24023 (service libvirt-service-type
24024 (libvirt-configuration
24025 (unix-sock-group "libvirt")
24026 (tls-port "16555")))
24030 @c Auto-generated with (generate-libvirt-documentation)
24031 Available @code{libvirt-configuration} fields are:
24033 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
24038 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
24039 Flag listening for secure TLS connections on the public TCP/IP port.
24040 must set @code{listen} for this to have any effect.
24042 It is necessary to setup a CA and issue server certificates before using
24045 Defaults to @samp{#t}.
24049 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
24050 Listen for unencrypted TCP connections on the public TCP/IP port. must
24051 set @code{listen} for this to have any effect.
24053 Using the TCP socket requires SASL authentication by default. Only SASL
24054 mechanisms which support data encryption are allowed. This is
24055 DIGEST_MD5 and GSSAPI (Kerberos5)
24057 Defaults to @samp{#f}.
24061 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
24062 Port for accepting secure TLS connections This can be a port number, or
24065 Defaults to @samp{"16514"}.
24069 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
24070 Port for accepting insecure TCP connections This can be a port number,
24073 Defaults to @samp{"16509"}.
24077 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
24078 IP address or hostname used for client connections.
24080 Defaults to @samp{"0.0.0.0"}.
24084 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
24085 Flag toggling mDNS advertisement of the libvirt service.
24087 Alternatively can disable for all services on a host by stopping the
24090 Defaults to @samp{#f}.
24094 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
24095 Default mDNS advertisement name. This must be unique on the immediate
24098 Defaults to @samp{"Virtualization Host <hostname>"}.
24102 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
24103 UNIX domain socket group ownership. This can be used to allow a
24104 'trusted' set of users access to management capabilities without
24107 Defaults to @samp{"root"}.
24111 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
24112 UNIX socket permissions for the R/O socket. This is used for monitoring
24115 Defaults to @samp{"0777"}.
24119 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
24120 UNIX socket permissions for the R/W socket. Default allows only root.
24121 If PolicyKit is enabled on the socket, the default will change to allow
24122 everyone (eg, 0777)
24124 Defaults to @samp{"0770"}.
24128 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
24129 UNIX socket permissions for the admin socket. Default allows only owner
24130 (root), do not change it unless you are sure to whom you are exposing
24133 Defaults to @samp{"0777"}.
24137 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
24138 The directory in which sockets will be found/created.
24140 Defaults to @samp{"/var/run/libvirt"}.
24144 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
24145 Authentication scheme for UNIX read-only sockets. By default socket
24146 permissions allow anyone to connect
24148 Defaults to @samp{"polkit"}.
24152 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
24153 Authentication scheme for UNIX read-write sockets. By default socket
24154 permissions only allow root. If PolicyKit support was compiled into
24155 libvirt, the default will be to use 'polkit' auth.
24157 Defaults to @samp{"polkit"}.
24161 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
24162 Authentication scheme for TCP sockets. If you don't enable SASL, then
24163 all TCP traffic is cleartext. Don't do this outside of a dev/test
24166 Defaults to @samp{"sasl"}.
24170 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
24171 Authentication scheme for TLS sockets. TLS sockets already have
24172 encryption provided by the TLS layer, and limited authentication is done
24175 It is possible to make use of any SASL authentication mechanism as well,
24176 by using 'sasl' for this option
24178 Defaults to @samp{"none"}.
24182 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
24183 API access control scheme.
24185 By default an authenticated user is allowed access to all APIs. Access
24186 drivers can place restrictions on this.
24188 Defaults to @samp{()}.
24192 @deftypevr {@code{libvirt-configuration} parameter} string key-file
24193 Server key file path. If set to an empty string, then no private key is
24196 Defaults to @samp{""}.
24200 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
24201 Server key file path. If set to an empty string, then no certificate is
24204 Defaults to @samp{""}.
24208 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
24209 Server key file path. If set to an empty string, then no CA certificate
24212 Defaults to @samp{""}.
24216 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
24217 Certificate revocation list path. If set to an empty string, then no
24220 Defaults to @samp{""}.
24224 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
24225 Disable verification of our own server certificates.
24227 When libvirtd starts it performs some sanity checks against its own
24230 Defaults to @samp{#f}.
24234 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
24235 Disable verification of client certificates.
24237 Client certificate verification is the primary authentication mechanism.
24238 Any client which does not present a certificate signed by the CA will be
24241 Defaults to @samp{#f}.
24245 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
24246 Whitelist of allowed x509 Distinguished Name.
24248 Defaults to @samp{()}.
24252 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
24253 Whitelist of allowed SASL usernames. The format for username depends on
24254 the SASL authentication mechanism.
24256 Defaults to @samp{()}.
24260 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
24261 Override the compile time default TLS priority string. The default is
24262 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
24263 is desired for libvirt to deviate from the global default settings.
24265 Defaults to @samp{"NORMAL"}.
24269 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
24270 Maximum number of concurrent client connections to allow over all
24273 Defaults to @samp{5000}.
24277 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
24278 Maximum length of queue of connections waiting to be accepted by the
24279 daemon. Note, that some protocols supporting retransmission may obey
24280 this so that a later reattempt at connection succeeds.
24282 Defaults to @samp{1000}.
24286 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
24287 Maximum length of queue of accepted but not yet authenticated clients.
24288 Set this to zero to turn this feature off
24290 Defaults to @samp{20}.
24294 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
24295 Number of workers to start up initially.
24297 Defaults to @samp{5}.
24301 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
24302 Maximum number of worker threads.
24304 If the number of active clients exceeds @code{min-workers}, then more
24305 threads are spawned, up to max_workers limit. Typically you'd want
24306 max_workers to equal maximum number of clients allowed.
24308 Defaults to @samp{20}.
24312 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
24313 Number of priority workers. If all workers from above pool are stuck,
24314 some calls marked as high priority (notably domainDestroy) can be
24315 executed in this pool.
24317 Defaults to @samp{5}.
24321 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
24322 Total global limit on concurrent RPC calls.
24324 Defaults to @samp{20}.
24328 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
24329 Limit on concurrent requests from a single client connection. To avoid
24330 one client monopolizing the server this should be a small fraction of
24331 the global max_requests and max_workers parameter.
24333 Defaults to @samp{5}.
24337 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
24338 Same as @code{min-workers} but for the admin interface.
24340 Defaults to @samp{1}.
24344 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
24345 Same as @code{max-workers} but for the admin interface.
24347 Defaults to @samp{5}.
24351 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
24352 Same as @code{max-clients} but for the admin interface.
24354 Defaults to @samp{5}.
24358 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
24359 Same as @code{max-queued-clients} but for the admin interface.
24361 Defaults to @samp{5}.
24365 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
24366 Same as @code{max-client-requests} but for the admin interface.
24368 Defaults to @samp{5}.
24372 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
24373 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
24375 Defaults to @samp{3}.
24379 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
24382 A filter allows to select a different logging level for a given category
24383 of logs The format for a filter is one of:
24394 where @code{name} is a string which is matched against the category
24395 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
24396 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
24397 name in the filter can be a substring of the full category name, in
24398 order to match multiple similar categories), the optional @samp{"+"}
24399 prefix tells libvirt to log stack trace for each message matching name,
24400 and @code{x} is the minimal level where matching messages should be
24418 Multiple filters can be defined in a single filters statement, they just
24419 need to be separated by spaces.
24421 Defaults to @samp{"3:remote 4:event"}.
24425 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
24428 An output is one of the places to save logging information. The format
24429 for an output can be:
24433 output goes to stderr
24435 @item x:syslog:name
24436 use syslog for the output and use the given name as the ident
24438 @item x:file:file_path
24439 output to a file, with the given filepath
24442 output to journald logging system
24446 In all case the x prefix is the minimal level, acting as a filter
24463 Multiple outputs can be defined, they just need to be separated by
24466 Defaults to @samp{"3:stderr"}.
24470 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
24471 Allows usage of the auditing subsystem to be altered
24475 0: disable all auditing
24478 1: enable auditing, only if enabled on host
24481 2: enable auditing, and exit if disabled on host.
24485 Defaults to @samp{1}.
24489 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
24490 Send audit messages via libvirt logging infrastructure.
24492 Defaults to @samp{#f}.
24496 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
24497 Host UUID. UUID must not have all digits be the same.
24499 Defaults to @samp{""}.
24503 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
24504 Source to read host UUID.
24508 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
24511 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
24515 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
24518 Defaults to @samp{"smbios"}.
24522 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
24523 A keepalive message is sent to a client after @code{keepalive_interval}
24524 seconds of inactivity to check if the client is still responding. If
24525 set to -1, libvirtd will never send keepalive requests; however clients
24526 can still send them and the daemon will send responses.
24528 Defaults to @samp{5}.
24532 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
24533 Maximum number of keepalive messages that are allowed to be sent to the
24534 client without getting any response before the connection is considered
24537 In other words, the connection is automatically closed approximately
24538 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
24539 the last message received from the client. When @code{keepalive-count}
24540 is set to 0, connections will be automatically closed after
24541 @code{keepalive-interval} seconds of inactivity without sending any
24542 keepalive messages.
24544 Defaults to @samp{5}.
24548 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
24549 Same as above but for admin interface.
24551 Defaults to @samp{5}.
24555 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
24556 Same as above but for admin interface.
24558 Defaults to @samp{5}.
24562 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
24563 Timeout for Open vSwitch calls.
24565 The @code{ovs-vsctl} utility is used for the configuration and its
24566 timeout option is set by default to 5 seconds to avoid potential
24567 infinite waits blocking libvirt.
24569 Defaults to @samp{5}.
24573 @c %end of autogenerated docs
24575 @subsubheading Virtlog daemon
24576 The virtlogd service is a server side daemon component of libvirt that is
24577 used to manage logs from virtual machine consoles.
24579 This daemon is not used directly by libvirt client applications, rather it
24580 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
24581 standalone daemon, the main @code{libvirtd} daemon can be restarted without
24582 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
24583 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
24585 @deffn {Scheme Variable} virtlog-service-type
24586 This is the type of the virtlog daemon.
24587 Its value must be a @code{virtlog-configuration}.
24590 (service virtlog-service-type
24591 (virtlog-configuration
24592 (max-clients 1000)))
24596 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
24597 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
24599 Defaults to @samp{3}.
24603 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
24606 A filter allows to select a different logging level for a given category
24607 of logs The format for a filter is one of:
24618 where @code{name} is a string which is matched against the category
24619 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
24620 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
24621 be a substring of the full category name, in order to match multiple
24622 similar categories), the optional "+" prefix tells libvirt to log stack
24623 trace for each message matching name, and @code{x} is the minimal level
24624 where matching messages should be logged:
24641 Multiple filters can be defined in a single filters statement, they just
24642 need to be separated by spaces.
24644 Defaults to @samp{"3:remote 4:event"}.
24648 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
24651 An output is one of the places to save logging information The format
24652 for an output can be:
24656 output goes to stderr
24658 @item x:syslog:name
24659 use syslog for the output and use the given name as the ident
24661 @item x:file:file_path
24662 output to a file, with the given filepath
24665 output to journald logging system
24669 In all case the x prefix is the minimal level, acting as a filter
24686 Multiple outputs can be defined, they just need to be separated by
24689 Defaults to @samp{"3:stderr"}.
24693 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
24694 Maximum number of concurrent client connections to allow over all
24697 Defaults to @samp{1024}.
24701 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
24702 Maximum file size before rolling over.
24704 Defaults to @samp{2MB}
24708 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
24709 Maximum number of backup files to keep.
24711 Defaults to @samp{3}
24715 @subsubheading Transparent Emulation with QEMU
24718 @cindex @code{binfmt_misc}
24719 @code{qemu-binfmt-service-type} provides support for transparent
24720 emulation of program binaries built for different architectures---e.g.,
24721 it allows you to transparently execute an ARMv7 program on an x86_64
24722 machine. It achieves this by combining the @uref{https://www.qemu.org,
24723 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
24725 @defvr {Scheme Variable} qemu-binfmt-service-type
24726 This is the type of the QEMU/binfmt service for transparent emulation.
24727 Its value must be a @code{qemu-binfmt-configuration} object, which
24728 specifies the QEMU package to use as well as the architecture we want to
24732 (service qemu-binfmt-service-type
24733 (qemu-binfmt-configuration
24734 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
24737 In this example, we enable transparent emulation for the ARM and aarch64
24738 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
24739 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
24740 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
24743 @deftp {Data Type} qemu-binfmt-configuration
24744 This is the configuration for the @code{qemu-binfmt} service.
24747 @item @code{platforms} (default: @code{'()})
24748 The list of emulated QEMU platforms. Each item must be a @dfn{platform
24749 object} as returned by @code{lookup-qemu-platforms} (see below).
24751 @item @code{guix-support?} (default: @code{#f})
24752 When it is true, QEMU and all its dependencies are added to the build
24753 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
24754 @option{--chroot-directory} option}). This allows the @code{binfmt_misc}
24755 handlers to be used within the build environment, which in turn means
24756 that you can transparently build programs for another architecture.
24758 For example, let's suppose you're on an x86_64 machine and you have this
24762 (service qemu-binfmt-service-type
24763 (qemu-binfmt-configuration
24764 (platforms (lookup-qemu-platforms "arm"))
24765 (guix-support? #t)))
24771 guix build -s armhf-linux inkscape
24775 and it will build Inkscape for ARMv7 @emph{as if it were a native
24776 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
24777 if you'd like to test a package build for an architecture you don't have
24780 @item @code{qemu} (default: @code{qemu})
24781 The QEMU package to use.
24785 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
24786 Return the list of QEMU platform objects corresponding to
24787 @var{platforms}@dots{}. @var{platforms} must be a list of strings
24788 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
24789 @code{"mips64el"}, and so on.
24792 @deffn {Scheme Procedure} qemu-platform? @var{obj}
24793 Return true if @var{obj} is a platform object.
24796 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
24797 Return the name of @var{platform}---a string such as @code{"arm"}.
24801 @subsubheading The Hurd in a Virtual Machine
24803 @cindex @code{hurd}
24806 Service @code{hurd-vm} provides support for running GNU/Hurd in a
24807 virtual machine (VM), a so-called ``Childhurd''. The virtual machine is
24808 a Shepherd service that can be referred to by the names @code{hurd-vm}
24809 and @code{childhurd} and be controlled with commands such as:
24813 herd stop childhurd
24816 The given GNU/Hurd operating system configuration is cross-compiled.
24818 @defvr {Scheme Variable} hurd-vm-service-type
24819 This is the type of the Hurd in a Virtual Machine service. Its value
24820 must be a @code{hurd-vm-configuration} object, which specifies the
24821 operating system (@pxref{operating-system Reference}) and the disk size
24822 for the Hurd Virtual Machine, the QEMU package to use as well as the
24823 options for running it.
24828 (service hurd-vm-service-type
24829 (hurd-vm-configuration
24830 (disk-size (* 5000 (expt 2 20))) ;5G
24831 (memory-size 1024))) ;1024MiB
24834 would create a disk image big enough to build GNU@tie{}Hello, with some
24838 @deftp {Data Type} hurd-vm-configuration
24839 The data type representing the configuration for
24840 @code{hurd-vm-service-type}.
24843 @item @code{os} (default: @var{%hurd-vm-operating-system})
24844 The operating system to instantiate. This default is bare-bones with a
24845 permissive OpenSSH secure shell daemon listening on port 2222
24846 (@pxref{Networking Services, @code{openssh-service-type}}).
24848 @item @code{qemu} (default: @code{qemu-minimal})
24849 The QEMU package to use.
24851 @item @code{image} (default: @var{hurd-vm-disk-image})
24852 The procedure used to build the disk-image built from this
24855 @item @code{disk-size} (default: @code{'guess})
24856 The size of the disk image.
24858 @item @code{memory-size} (default: @code{512})
24859 The memory size of the Virtual Machine in mebibytes.
24861 @item @code{options} (default: @code{'("--snapshot")})
24862 The extra options for running QEMU.
24864 @item @code{id} (default: @code{#f})
24865 If set, a non-zero positive integer used to parameterize Childhurd
24866 instances. It is appended to the service's name,
24867 e.g. @code{childhurd1}.
24869 @item @code{net-options} (default: @var{hurd-vm-net-options})
24870 The procedure used to produce the list of QEMU networking options.
24872 By default, it produces
24875 '("--device" "rtl8139,netdev=net0"
24876 "--netdev" "user,id=net0\
24877 ,hostfwd=tcp:127.0.0.1:<ssh-port>-:2222\
24878 ,hostfwd=tcp:127.0.0.1:<vnc-port>-:5900")
24880 with forwarded ports
24882 <ssh-port>: @code{(+ 10022 (* 1000 @var{ID}))}
24883 <vnc-port>: @code{(+ 15900 (* 1000 @var{ID}))}
24889 Note that by default the VM image is volatile, i.e., once stopped the
24890 contents are lost. If you want a stateful image instead, override the
24891 configuration's @code{image} and @code{options} without
24892 the @code{--snapshot} flag using something along these lines:
24895 (service hurd-vm-service-type
24896 (hurd-vm-configuration
24897 (image (const "/out/of/store/writable/hurd.img"))
24898 (options '("--hda"))))
24901 @node Version Control Services
24902 @subsection Version Control Services
24904 The @code{(gnu services version-control)} module provides a service to
24905 allow remote access to local Git repositories. There are three options:
24906 the @code{git-daemon-service}, which provides access to repositories via
24907 the @code{git://} unsecured TCP-based protocol, extending the
24908 @code{nginx} web server to proxy some requests to
24909 @code{git-http-backend}, or providing a web interface with
24910 @code{cgit-service-type}.
24912 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
24914 Return a service that runs @command{git daemon}, a simple TCP server to
24915 expose repositories over the Git protocol for anonymous access.
24917 The optional @var{config} argument should be a
24918 @code{<git-daemon-configuration>} object, by default it allows read-only
24919 access to exported@footnote{By creating the magic file
24920 @file{git-daemon-export-ok} in the repository directory.} repositories under
24925 @deftp {Data Type} git-daemon-configuration
24926 Data type representing the configuration for @code{git-daemon-service}.
24929 @item @code{package} (default: @code{git})
24930 Package object of the Git distributed version control system.
24932 @item @code{export-all?} (default: @code{#f})
24933 Whether to allow access for all Git repositories, even if they do not
24934 have the @file{git-daemon-export-ok} file.
24936 @item @code{base-path} (default: @file{/srv/git})
24937 Whether to remap all the path requests as relative to the given path.
24938 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
24939 @samp{example.com}, then if you later try to pull
24940 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
24941 path as @file{/srv/git/hello.git}.
24943 @item @code{user-path} (default: @code{#f})
24944 Whether to allow @code{~user} notation to be used in requests. When
24945 specified with empty string, requests to
24946 @indicateurl{git://host/~alice/foo} is taken as a request to access
24947 @code{foo} repository in the home directory of user @code{alice}. If
24948 @code{(user-path "@var{path}")} is specified, the same request is taken
24949 as a request to access @file{@var{path}/foo} repository in the home
24950 directory of user @code{alice}.
24952 @item @code{listen} (default: @code{'()})
24953 Whether to listen on specific IP addresses or hostnames, defaults to
24956 @item @code{port} (default: @code{#f})
24957 Whether to listen on an alternative port, which defaults to 9418.
24959 @item @code{whitelist} (default: @code{'()})
24960 If not empty, only allow access to this list of directories.
24962 @item @code{extra-options} (default: @code{'()})
24963 Extra options will be passed to @command{git daemon}, please run
24964 @command{man git-daemon} for more information.
24969 The @code{git://} protocol lacks authentication. When you pull from a
24970 repository fetched via @code{git://}, you don't know whether the data you
24971 receive was modified or is even coming from the specified host, and your
24972 connection is subject to eavesdropping. It's better to use an authenticated
24973 and encrypted transport, such as @code{https}. Although Git allows you
24974 to serve repositories using unsophisticated file-based web servers,
24975 there is a faster protocol implemented by the @code{git-http-backend}
24976 program. This program is the back-end of a proper Git web service. It
24977 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
24978 on running the necessary @code{fcgiwrap} daemon.
24980 Guix has a separate configuration data type for serving Git repositories
24983 @deftp {Data Type} git-http-configuration
24984 Data type representing the configuration for a future
24985 @code{git-http-service-type}; can currently be used to configure Nginx
24986 trough @code{git-http-nginx-location-configuration}.
24989 @item @code{package} (default: @var{git})
24990 Package object of the Git distributed version control system.
24992 @item @code{git-root} (default: @file{/srv/git})
24993 Directory containing the Git repositories to expose to the world.
24995 @item @code{export-all?} (default: @code{#f})
24996 Whether to expose access for all Git repositories in @var{git-root},
24997 even if they do not have the @file{git-daemon-export-ok} file.
24999 @item @code{uri-path} (default: @samp{/git/})
25000 Path prefix for Git access. With the default @samp{/git/} prefix, this
25001 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
25002 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
25003 with this prefix are not passed on to this Git instance.
25005 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
25006 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
25011 There is no @code{git-http-service-type}, currently; instead you can
25012 create an @code{nginx-location-configuration} from a
25013 @code{git-http-configuration} and then add that location to a web
25016 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
25017 [config=(git-http-configuration)]
25018 Compute an @code{nginx-location-configuration} that corresponds to the
25019 given Git http configuration. An example nginx service definition to
25020 serve the default @file{/srv/git} over HTTPS might be:
25023 (service nginx-service-type
25024 (nginx-configuration
25027 (nginx-server-configuration
25028 (listen '("443 ssl"))
25029 (server-name "git.my-host.org")
25031 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
25032 (ssl-certificate-key
25033 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
25036 (git-http-nginx-location-configuration
25037 (git-http-configuration (uri-path "/"))))))))))
25040 This example assumes that you are using Let's Encrypt to get your TLS
25041 certificate. @xref{Certificate Services}. The default @code{certbot}
25042 service will redirect all HTTP traffic on @code{git.my-host.org} to
25043 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
25044 system services. @xref{Web Services}.
25047 @subsubheading Cgit Service
25049 @cindex Cgit service
25050 @cindex Git, web interface
25051 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
25052 repositories written in C.
25054 The following example will configure the service with default values.
25055 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
25058 (service cgit-service-type)
25061 The @code{file-object} type designates either a file-like object
25062 (@pxref{G-Expressions, file-like objects}) or a string.
25064 @c %start of fragment
25066 Available @code{cgit-configuration} fields are:
25068 @deftypevr {@code{cgit-configuration} parameter} package package
25073 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
25074 NGINX configuration.
25078 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
25079 Specifies a command which will be invoked to format the content of about
25080 pages (both top-level and for each repository).
25082 Defaults to @samp{""}.
25086 @deftypevr {@code{cgit-configuration} parameter} string agefile
25087 Specifies a path, relative to each repository path, which can be used to
25088 specify the date and time of the youngest commit in the repository.
25090 Defaults to @samp{""}.
25094 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
25095 Specifies a command that will be invoked for authenticating repository
25098 Defaults to @samp{""}.
25102 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
25103 Flag which, when set to @samp{age}, enables date ordering in the branch
25104 ref list, and when set @samp{name} enables ordering by branch name.
25106 Defaults to @samp{"name"}.
25110 @deftypevr {@code{cgit-configuration} parameter} string cache-root
25111 Path used to store the cgit cache entries.
25113 Defaults to @samp{"/var/cache/cgit"}.
25117 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
25118 Number which specifies the time-to-live, in minutes, for the cached
25119 version of repository pages accessed with a fixed SHA1.
25121 Defaults to @samp{-1}.
25125 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
25126 Number which specifies the time-to-live, in minutes, for the cached
25127 version of repository pages accessed without a fixed SHA1.
25129 Defaults to @samp{5}.
25133 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
25134 Number which specifies the time-to-live, in minutes, for the cached
25135 version of the repository summary page.
25137 Defaults to @samp{5}.
25141 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
25142 Number which specifies the time-to-live, in minutes, for the cached
25143 version of the repository index page.
25145 Defaults to @samp{5}.
25149 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
25150 Number which specifies the time-to-live, in minutes, for the result of
25151 scanning a path for Git repositories.
25153 Defaults to @samp{15}.
25157 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
25158 Number which specifies the time-to-live, in minutes, for the cached
25159 version of the repository about page.
25161 Defaults to @samp{15}.
25165 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
25166 Number which specifies the time-to-live, in minutes, for the cached
25167 version of snapshots.
25169 Defaults to @samp{5}.
25173 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
25174 The maximum number of entries in the cgit cache. When set to @samp{0},
25175 caching is disabled.
25177 Defaults to @samp{0}.
25181 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
25182 Sort items in the repo list case sensitively.
25184 Defaults to @samp{#t}.
25188 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
25189 List of common prefixes which, when combined with a repository URL,
25190 generates valid clone URLs for the repository.
25192 Defaults to @samp{()}.
25196 @deftypevr {@code{cgit-configuration} parameter} list clone-url
25197 List of @code{clone-url} templates.
25199 Defaults to @samp{()}.
25203 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
25204 Command which will be invoked to format commit messages.
25206 Defaults to @samp{""}.
25210 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
25211 Flag which, when set to @samp{date}, enables strict date ordering in the
25212 commit log, and when set to @samp{topo} enables strict topological
25215 Defaults to @samp{"git log"}.
25219 @deftypevr {@code{cgit-configuration} parameter} file-object css
25220 URL which specifies the css document to include in all cgit pages.
25222 Defaults to @samp{"/share/cgit/cgit.css"}.
25226 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
25227 Specifies a command which will be invoked to format names and email
25228 address of committers, authors, and taggers, as represented in various
25229 places throughout the cgit interface.
25231 Defaults to @samp{""}.
25235 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
25236 Flag which, when set to @samp{#t}, will make cgit generate a HTML
25237 fragment suitable for embedding in other HTML pages.
25239 Defaults to @samp{#f}.
25243 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
25244 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
25245 commit history graph to the left of the commit messages in the
25246 repository log page.
25248 Defaults to @samp{#f}.
25252 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
25253 Flag which, when set to @samp{#t}, allows all filter settings to be
25254 overridden in repository-specific cgitrc files.
25256 Defaults to @samp{#f}.
25260 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
25261 Flag which, when set to @samp{#t}, allows users to follow a file in the
25264 Defaults to @samp{#f}.
25268 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
25269 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
25272 Defaults to @samp{#t}.
25276 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
25277 Flag which, when set to @samp{#t}, will make cgit generate extra links
25278 "summary", "commit", "tree" for each repo in the repository index.
25280 Defaults to @samp{#f}.
25284 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
25285 Flag which, when set to @samp{#t}, will make cgit display the owner of
25286 each repo in the repository index.
25288 Defaults to @samp{#t}.
25292 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
25293 Flag which, when set to @samp{#t}, will make cgit print the number of
25294 modified files for each commit on the repository log page.
25296 Defaults to @samp{#f}.
25300 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
25301 Flag which, when set to @samp{#t}, will make cgit print the number of
25302 added and removed lines for each commit on the repository log page.
25304 Defaults to @samp{#f}.
25308 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
25309 Flag which, when set to @code{#t}, will make cgit display remote
25310 branches in the summary and refs views.
25312 Defaults to @samp{#f}.
25316 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
25317 Flag which, when set to @code{1}, will make cgit use the subject of the
25318 parent commit as link text when generating links to parent commits in
25321 Defaults to @samp{#f}.
25325 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
25326 Flag which, when set to @samp{#t}, will make cgit use the subject of the
25327 parent commit as link text when generating links to parent commits in
25330 Defaults to @samp{#f}.
25334 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
25335 Flag which, when set to @samp{#t}, will make cgit generate linenumber
25336 links for plaintext blobs printed in the tree view.
25338 Defaults to @samp{#t}.
25342 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
25343 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
25344 set any repo specific settings.
25346 Defaults to @samp{#f}.
25350 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
25351 URL used as link to a shortcut icon for cgit.
25353 Defaults to @samp{"/favicon.ico"}.
25357 @deftypevr {@code{cgit-configuration} parameter} string footer
25358 The content of the file specified with this option will be included
25359 verbatim at the bottom of all pages (i.e.@: it replaces the standard
25360 "generated by..."@: message).
25362 Defaults to @samp{""}.
25366 @deftypevr {@code{cgit-configuration} parameter} string head-include
25367 The content of the file specified with this option will be included
25368 verbatim in the HTML HEAD section on all pages.
25370 Defaults to @samp{""}.
25374 @deftypevr {@code{cgit-configuration} parameter} string header
25375 The content of the file specified with this option will be included
25376 verbatim at the top of all pages.
25378 Defaults to @samp{""}.
25382 @deftypevr {@code{cgit-configuration} parameter} file-object include
25383 Name of a configfile to include before the rest of the current config-
25386 Defaults to @samp{""}.
25390 @deftypevr {@code{cgit-configuration} parameter} string index-header
25391 The content of the file specified with this option will be included
25392 verbatim above the repository index.
25394 Defaults to @samp{""}.
25398 @deftypevr {@code{cgit-configuration} parameter} string index-info
25399 The content of the file specified with this option will be included
25400 verbatim below the heading on the repository index page.
25402 Defaults to @samp{""}.
25406 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
25407 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
25408 in the servers timezone.
25410 Defaults to @samp{#f}.
25414 @deftypevr {@code{cgit-configuration} parameter} file-object logo
25415 URL which specifies the source of an image which will be used as a logo
25418 Defaults to @samp{"/share/cgit/cgit.png"}.
25422 @deftypevr {@code{cgit-configuration} parameter} string logo-link
25423 URL loaded when clicking on the cgit logo image.
25425 Defaults to @samp{""}.
25429 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
25430 Command which will be invoked to format the Owner column of the main
25433 Defaults to @samp{""}.
25437 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
25438 Number of items to display in atom feeds view.
25440 Defaults to @samp{10}.
25444 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
25445 Number of entries to list per page in "log" view.
25447 Defaults to @samp{50}.
25451 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
25452 Number of commit message characters to display in "log" view.
25454 Defaults to @samp{80}.
25458 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
25459 Specifies the number of entries to list per page on the repository index
25462 Defaults to @samp{50}.
25466 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
25467 Specifies the maximum number of repo description characters to display
25468 on the repository index page.
25470 Defaults to @samp{80}.
25474 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
25475 Specifies the maximum size of a blob to display HTML for in KBytes.
25477 Defaults to @samp{0}.
25481 @deftypevr {@code{cgit-configuration} parameter} string max-stats
25482 Maximum statistics period. Valid values are @samp{week},@samp{month},
25483 @samp{quarter} and @samp{year}.
25485 Defaults to @samp{""}.
25489 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
25490 Mimetype for the specified filename extension.
25492 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
25493 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
25494 "image/png") (svg "image/svg+xml"))}.
25498 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
25499 Specifies the file to use for automatic mimetype lookup.
25501 Defaults to @samp{""}.
25505 @deftypevr {@code{cgit-configuration} parameter} string module-link
25506 Text which will be used as the formatstring for a hyperlink when a
25507 submodule is printed in a directory listing.
25509 Defaults to @samp{""}.
25513 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
25514 If set to the value @samp{#t} caching will be disabled.
25516 Defaults to @samp{#f}.
25520 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
25521 If set to @samp{#t} showing full author email addresses will be
25524 Defaults to @samp{#f}.
25528 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
25529 Flag which, when set to @samp{#t}, will make cgit omit the standard
25530 header on all pages.
25532 Defaults to @samp{#f}.
25536 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
25537 A list of subdirectories inside of @code{repository-directory}, relative
25538 to it, that should loaded as Git repositories. An empty list means that
25539 all subdirectories will be loaded.
25541 Defaults to @samp{()}.
25545 @deftypevr {@code{cgit-configuration} parameter} file-object readme
25546 Text which will be used as default value for @code{cgit-repo-readme}.
25548 Defaults to @samp{""}.
25552 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
25553 If set to @code{#t} and @code{repository-directory} is enabled, if any
25554 repositories are found with a suffix of @code{.git}, this suffix will be
25555 removed for the URL and name.
25557 Defaults to @samp{#f}.
25561 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
25562 Maximum number of files to consider when detecting renames.
25564 Defaults to @samp{-1}.
25568 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
25569 The way in which repositories in each section are sorted.
25571 Defaults to @samp{""}.
25575 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
25576 Text used as content for the @code{robots} meta-tag.
25578 Defaults to @samp{("noindex" "nofollow")}.
25582 @deftypevr {@code{cgit-configuration} parameter} string root-desc
25583 Text printed below the heading on the repository index page.
25585 Defaults to @samp{"a fast webinterface for the git dscm"}.
25589 @deftypevr {@code{cgit-configuration} parameter} string root-readme
25590 The content of the file specified with this option will be included
25591 verbatim below the ``about'' link on the repository index page.
25593 Defaults to @samp{""}.
25597 @deftypevr {@code{cgit-configuration} parameter} string root-title
25598 Text printed as heading on the repository index page.
25600 Defaults to @samp{""}.
25604 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
25605 If set to @samp{#t} and repository-directory is enabled,
25606 repository-directory will recurse into directories whose name starts
25607 with a period. Otherwise, repository-directory will stay away from such
25608 directories, considered as ``hidden''. Note that this does not apply to
25609 the @file{.git} directory in non-bare repos.
25611 Defaults to @samp{#f}.
25615 @deftypevr {@code{cgit-configuration} parameter} list snapshots
25616 Text which specifies the default set of snapshot formats that cgit
25617 generates links for.
25619 Defaults to @samp{()}.
25623 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
25624 Name of the directory to scan for repositories (represents
25627 Defaults to @samp{"/srv/git"}.
25631 @deftypevr {@code{cgit-configuration} parameter} string section
25632 The name of the current repository section - all repositories defined
25633 after this option will inherit the current section name.
25635 Defaults to @samp{""}.
25639 @deftypevr {@code{cgit-configuration} parameter} string section-sort
25640 Flag which, when set to @samp{1}, will sort the sections on the
25641 repository listing by name.
25643 Defaults to @samp{""}.
25647 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
25648 A number which, if defined prior to repository-directory, specifies how
25649 many path elements from each repo path to use as a default section name.
25651 Defaults to @samp{0}.
25655 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
25656 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
25659 Defaults to @samp{#f}.
25663 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
25664 Specifies a command which will be invoked to format plaintext blobs in
25667 Defaults to @samp{""}.
25671 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
25672 Specifies the number of branches to display in the repository ``summary''
25675 Defaults to @samp{10}.
25679 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
25680 Specifies the number of log entries to display in the repository
25683 Defaults to @samp{10}.
25687 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
25688 Specifies the number of tags to display in the repository ``summary''
25691 Defaults to @samp{10}.
25695 @deftypevr {@code{cgit-configuration} parameter} string strict-export
25696 Filename which, if specified, needs to be present within the repository
25697 for cgit to allow access to that repository.
25699 Defaults to @samp{""}.
25703 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
25704 URL which, if specified, will be used as root for all cgit links.
25706 Defaults to @samp{"/"}.
25710 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
25711 A list of @dfn{cgit-repo} records to use with config.
25713 Defaults to @samp{()}.
25715 Available @code{repository-cgit-configuration} fields are:
25717 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
25718 A mask of snapshot formats for this repo that cgit generates links for,
25719 restricted by the global @code{snapshots} setting.
25721 Defaults to @samp{()}.
25725 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
25726 Override the default @code{source-filter}.
25728 Defaults to @samp{""}.
25732 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
25733 The relative URL used to access the repository.
25735 Defaults to @samp{""}.
25739 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
25740 Override the default @code{about-filter}.
25742 Defaults to @samp{""}.
25746 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
25747 Flag which, when set to @samp{age}, enables date ordering in the branch
25748 ref list, and when set to @samp{name} enables ordering by branch name.
25750 Defaults to @samp{""}.
25754 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
25755 A list of URLs which can be used to clone repo.
25757 Defaults to @samp{()}.
25761 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
25762 Override the default @code{commit-filter}.
25764 Defaults to @samp{""}.
25768 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
25769 Flag which, when set to @samp{date}, enables strict date ordering in the
25770 commit log, and when set to @samp{topo} enables strict topological
25773 Defaults to @samp{""}.
25777 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
25778 The name of the default branch for this repository. If no such branch
25779 exists in the repository, the first branch name (when sorted) is used as
25780 default instead. By default branch pointed to by HEAD, or ``master'' if
25781 there is no suitable HEAD.
25783 Defaults to @samp{""}.
25787 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
25788 The value to show as repository description.
25790 Defaults to @samp{""}.
25794 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
25795 The value to show as repository homepage.
25797 Defaults to @samp{""}.
25801 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
25802 Override the default @code{email-filter}.
25804 Defaults to @samp{""}.
25808 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
25809 A flag which can be used to disable the global setting
25810 @code{enable-commit-graph?}.
25812 Defaults to @samp{disabled}.
25816 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
25817 A flag which can be used to disable the global setting
25818 @code{enable-log-filecount?}.
25820 Defaults to @samp{disabled}.
25824 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
25825 A flag which can be used to disable the global setting
25826 @code{enable-log-linecount?}.
25828 Defaults to @samp{disabled}.
25832 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
25833 Flag which, when set to @code{#t}, will make cgit display remote
25834 branches in the summary and refs views.
25836 Defaults to @samp{disabled}.
25840 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
25841 A flag which can be used to override the global setting
25842 @code{enable-subject-links?}.
25844 Defaults to @samp{disabled}.
25848 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
25849 A flag which can be used to override the global setting
25850 @code{enable-html-serving?}.
25852 Defaults to @samp{disabled}.
25856 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
25857 Flag which, when set to @code{#t}, hides the repository from the
25860 Defaults to @samp{#f}.
25864 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
25865 Flag which, when set to @samp{#t}, ignores the repository.
25867 Defaults to @samp{#f}.
25871 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
25872 URL which specifies the source of an image which will be used as a logo
25873 on this repo’s pages.
25875 Defaults to @samp{""}.
25879 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
25880 URL loaded when clicking on the cgit logo image.
25882 Defaults to @samp{""}.
25886 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
25887 Override the default @code{owner-filter}.
25889 Defaults to @samp{""}.
25893 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
25894 Text which will be used as the formatstring for a hyperlink when a
25895 submodule is printed in a directory listing. The arguments for the
25896 formatstring are the path and SHA1 of the submodule commit.
25898 Defaults to @samp{""}.
25902 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
25903 Text which will be used as the formatstring for a hyperlink when a
25904 submodule with the specified subdirectory path is printed in a directory
25907 Defaults to @samp{()}.
25911 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
25912 Override the default maximum statistics period.
25914 Defaults to @samp{""}.
25918 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
25919 The value to show as repository name.
25921 Defaults to @samp{""}.
25925 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
25926 A value used to identify the owner of the repository.
25928 Defaults to @samp{""}.
25932 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
25933 An absolute path to the repository directory.
25935 Defaults to @samp{""}.
25939 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
25940 A path (relative to repo) which specifies a file to include verbatim as
25941 the ``About'' page for this repo.
25943 Defaults to @samp{""}.
25947 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
25948 The name of the current repository section - all repositories defined
25949 after this option will inherit the current section name.
25951 Defaults to @samp{""}.
25955 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
25956 Extra options will be appended to cgitrc file.
25958 Defaults to @samp{()}.
25964 @deftypevr {@code{cgit-configuration} parameter} list extra-options
25965 Extra options will be appended to cgitrc file.
25967 Defaults to @samp{()}.
25972 @c %end of fragment
25974 However, it could be that you just want to get a @code{cgitrc} up and
25975 running. In that case, you can pass an @code{opaque-cgit-configuration}
25976 as a record to @code{cgit-service-type}. As its name indicates, an
25977 opaque configuration does not have easy reflective capabilities.
25979 Available @code{opaque-cgit-configuration} fields are:
25981 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
25985 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
25986 The contents of the @code{cgitrc}, as a string.
25989 For example, if your @code{cgitrc} is just the empty string, you
25990 could instantiate a cgit service like this:
25993 (service cgit-service-type
25994 (opaque-cgit-configuration
25998 @subsubheading Gitolite Service
26000 @cindex Gitolite service
26001 @cindex Git, hosting
26002 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
26003 repositories on a central server.
26005 Gitolite can handle multiple repositories and users, and supports flexible
26006 configuration of the permissions for the users on the repositories.
26008 The following example will configure Gitolite using the default @code{git}
26009 user, and the provided SSH public key.
26012 (service gitolite-service-type
26013 (gitolite-configuration
26014 (admin-pubkey (plain-file
26016 "ssh-rsa AAAA... guix@@example.com"))))
26019 Gitolite is configured through a special admin repository which you can clone,
26020 for example, if you setup Gitolite on @code{example.com}, you would run the
26021 following command to clone the admin repository.
26024 git clone git@@example.com:gitolite-admin
26027 When the Gitolite service is activated, the provided @code{admin-pubkey} will
26028 be inserted in to the @file{keydir} directory in the gitolite-admin
26029 repository. If this results in a change in the repository, it will be
26030 committed using the message ``gitolite setup by GNU Guix''.
26032 @deftp {Data Type} gitolite-configuration
26033 Data type representing the configuration for @code{gitolite-service-type}.
26036 @item @code{package} (default: @var{gitolite})
26037 Gitolite package to use.
26039 @item @code{user} (default: @var{git})
26040 User to use for Gitolite. This will be user that you use when accessing
26043 @item @code{group} (default: @var{git})
26044 Group to use for Gitolite.
26046 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
26047 Directory in which to store the Gitolite configuration and repositories.
26049 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
26050 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
26051 representing the configuration for Gitolite.
26053 @item @code{admin-pubkey} (default: @var{#f})
26054 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
26055 setup Gitolite. This will be inserted in to the @file{keydir} directory
26056 within the gitolite-admin repository.
26058 To specify the SSH key as a string, use the @code{plain-file} function.
26061 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
26067 @deftp {Data Type} gitolite-rc-file
26068 Data type representing the Gitolite RC file.
26071 @item @code{umask} (default: @code{#o0077})
26072 This controls the permissions Gitolite sets on the repositories and their
26075 A value like @code{#o0027} will give read access to the group used by Gitolite
26076 (by default: @code{git}). This is necessary when using Gitolite with software
26077 like cgit or gitweb.
26079 @item @code{git-config-keys} (default: @code{""})
26080 Gitolite allows you to set git config values using the @samp{config} keyword. This
26081 setting allows control over the config keys to accept.
26083 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
26084 Set the role names allowed to be used by users running the perms command.
26086 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
26087 This setting controls the commands and features to enable within Gitolite.
26093 @node Game Services
26094 @subsection Game Services
26096 @subsubheading The Battle for Wesnoth Service
26098 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
26099 based tactical strategy game, with several single player campaigns, and
26100 multiplayer games (both networked and local).
26102 @defvar {Scheme Variable} wesnothd-service-type
26103 Service type for the wesnothd service. Its value must be a
26104 @code{wesnothd-configuration} object. To run wesnothd in the default
26105 configuration, instantiate it as:
26108 (service wesnothd-service-type)
26112 @deftp {Data Type} wesnothd-configuration
26113 Data type representing the configuration of @command{wesnothd}.
26116 @item @code{package} (default: @code{wesnoth-server})
26117 The wesnoth server package to use.
26119 @item @code{port} (default: @code{15000})
26120 The port to bind the server to.
26125 @node PAM Mount Service
26126 @subsection PAM Mount Service
26129 The @code{(gnu services pam-mount)} module provides a service allowing
26130 users to mount volumes when they log in. It should be able to mount any
26131 volume format supported by the system.
26133 @defvar {Scheme Variable} pam-mount-service-type
26134 Service type for PAM Mount support.
26137 @deftp {Data Type} pam-mount-configuration
26138 Data type representing the configuration of PAM Mount.
26140 It takes the following parameters:
26144 The configuration rules that will be used to generate
26145 @file{/etc/security/pam_mount.conf.xml}.
26147 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
26148 Guile Reference Manual}), and the the default ones don't mount anything
26149 for anyone at login:
26152 `((debug (@@ (enable "0")))
26153 (mntoptions (@@ (allow ,(string-join
26154 '("nosuid" "nodev" "loop"
26155 "encryption" "fsck" "nonempty"
26156 "allow_root" "allow_other")
26158 (mntoptions (@@ (require "nosuid,nodev")))
26159 (logout (@@ (wait "0")
26163 (mkmountpoint (@@ (enable "1")
26167 Some @code{volume} elements must be added to automatically mount volumes
26168 at login. Here's an example allowing the user @code{alice} to mount her
26169 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
26170 the partition where he stores his data:
26173 (define pam-mount-rules
26174 `((debug (@@ (enable "0")))
26175 (volume (@@ (user "alice")
26178 (mountpoint "/home/alice")))
26179 (volume (@@ (user "bob")
26182 (mountpoint "/home/bob/data")
26183 (options "defaults,autodefrag,compress")))
26184 (mntoptions (@@ (allow ,(string-join
26185 '("nosuid" "nodev" "loop"
26186 "encryption" "fsck" "nonempty"
26187 "allow_root" "allow_other")
26189 (mntoptions (@@ (require "nosuid,nodev")))
26190 (logout (@@ (wait "0")
26194 (mkmountpoint (@@ (enable "1")
26195 (remove "true")))))
26197 (service pam-mount-service-type
26198 (pam-mount-configuration
26199 (rules pam-mount-rules)))
26202 The complete list of possible options can be found in the man page for
26203 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
26208 @node Guix Services
26209 @subsection Guix Services
26211 @subsubheading Guix Data Service
26212 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
26213 and provides data about GNU Guix. This includes information about
26214 packages, derivations and lint warnings.
26216 The data is stored in a PostgreSQL database, and available through a web
26219 @defvar {Scheme Variable} guix-data-service-type
26220 Service type for the Guix Data Service. Its value must be a
26221 @code{guix-data-service-configuration} object. The service optionally
26222 extends the getmail service, as the guix-commits mailing list is used to
26223 find out about changes in the Guix git repository.
26226 @deftp {Data Type} guix-data-service-configuration
26227 Data type representing the configuration of the Guix Data Service.
26230 @item @code{package} (default: @code{guix-data-service})
26231 The Guix Data Service package to use.
26233 @item @code{user} (default: @code{"guix-data-service"})
26234 The system user to run the service as.
26236 @item @code{group} (default: @code{"guix-data-service"})
26237 The system group to run the service as.
26239 @item @code{port} (default: @code{8765})
26240 The port to bind the web service to.
26242 @item @code{host} (default: @code{"127.0.0.1"})
26243 The host to bind the web service to.
26245 @item @code{getmail-idle-mailboxes} (default: @code{#f})
26246 If set, this is the list of mailboxes that the getmail service will be
26247 configured to listen to.
26249 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
26250 If set, this is the @code{getmail-retriever-configuration} object with
26251 which to configure getmail to fetch mail from the guix-commits mailing
26254 @item @code{extra-options} (default: @var{'()})
26255 Extra command line options for @code{guix-data-service}.
26257 @item @code{extra-process-jobs-options} (default: @var{'()})
26258 Extra command line options for @code{guix-data-service-process-jobs}.
26263 @node Linux Services
26264 @subsection Linux Services
26267 @cindex out of memory killer
26269 @cindex early out of memory daemon
26270 @subsubheading Early OOM Service
26272 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
26273 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
26274 space and provides a more responsive and configurable alternative to the
26275 in-kernel OOM killer. It is useful to prevent the system from becoming
26276 unresponsive when it runs out of memory.
26278 @deffn {Scheme Variable} earlyoom-service-type
26279 The service type for running @command{earlyoom}, the Early OOM daemon.
26280 Its value must be a @code{earlyoom-configuration} object, described
26281 below. The service can be instantiated in its default configuration
26285 (service earlyoom-service-type)
26289 @deftp {Data Type} earlyoom-configuration
26290 This is the configuration record for the @code{earlyoom-service-type}.
26293 @item @code{earlyoom} (default: @var{earlyoom})
26294 The Earlyoom package to use.
26296 @item @code{minimum-available-memory} (default: @code{10})
26297 The threshold for the minimum @emph{available} memory, in percentages.
26299 @item @code{minimum-free-swap} (default: @code{10})
26300 The threshold for the minimum free swap memory, in percentages.
26302 @item @code{prefer-regexp} (default: @code{#f})
26303 A regular expression (as a string) to match the names of the processes
26304 that should be preferably killed.
26306 @item @code{avoid-regexp} (default: @code{#f})
26307 A regular expression (as a string) to match the names of the processes
26308 that should @emph{not} be killed.
26310 @item @code{memory-report-interval} (default: @code{0})
26311 The interval in seconds at which a memory report is printed. It is
26312 disabled by default.
26314 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
26315 A boolean indicating whether the positive adjustments set in
26316 @file{/proc/*/oom_score_adj}.
26318 @item @code{show-debug-messages?} (default: @code{#f})
26319 A boolean indicating whether debug messages should be printed. The logs
26320 are saved at @file{/var/log/earlyoom.log}.
26322 @item @code{send-notification-command} (default: @code{#f})
26323 This can be used to provide a custom command used for sending
26329 @cindex kernel module loader
26330 @subsubheading Kernel Module Loader Service
26332 The kernel module loader service allows one to load loadable kernel
26333 modules at boot. This is especially useful for modules that don't
26334 autoload and need to be manually loaded, as it's the case with
26337 @deffn {Scheme Variable} kernel-module-loader-service-type
26338 The service type for loading loadable kernel modules at boot with
26339 @command{modprobe}. Its value must be a list of strings representing
26340 module names. For example loading the drivers provided by
26341 @code{ddcci-driver-linux}, in debugging mode by passing some module
26342 parameters, can be done as follow:
26345 (use-modules (gnu) (gnu services))
26346 (use-package-modules linux)
26347 (use-service-modules linux)
26349 (define ddcci-config
26350 (plain-file "ddcci.conf"
26351 "options ddcci dyndbg delay=120"))
26355 (services (cons* (service kernel-module-loader-service-type
26356 '("ddcci" "ddcci_backlight"))
26357 (simple-service 'ddcci-config etc-service-type
26358 (list `("modprobe.d/ddcci.conf"
26361 (kernel-loadable-modules (list ddcci-driver-linux)))
26365 @node Hurd Services
26366 @subsection Hurd Services
26368 @defvr {Scheme Variable} hurd-console-service-type
26369 This service starts the fancy @code{VGA} console client on the Hurd.
26371 The service's value is a @code{hurd-console-configuration} record.
26374 @deftp {Data Type} hurd-console-configuration
26375 This is the data type representing the configuration for the
26376 hurd-console-service.
26379 @item @code{hurd} (default: @var{hurd})
26380 The Hurd package to use.
26384 @defvr {Scheme Variable} hurd-getty-service-type
26385 This service starts a tty using the Hurd @code{getty} program.
26387 The service's value is a @code{hurd-getty-configuration} record.
26390 @deftp {Data Type} hurd-getty-configuration
26391 This is the data type representing the configuration for the
26392 hurd-getty-service.
26395 @item @code{hurd} (default: @var{hurd})
26396 The Hurd package to use.
26399 The name of the console this Getty runs on---e.g., @code{"tty1"}.
26401 @item @code{baud-rate} (default: @code{38400})
26402 An integer specifying the baud rate of the tty.
26407 @node Miscellaneous Services
26408 @subsection Miscellaneous Services
26410 @cindex fingerprint
26411 @subsubheading Fingerprint Service
26413 The @code{(gnu services authentication)} module provides a DBus service to
26414 read and identify fingerprints via a fingerprint sensor.
26416 @defvr {Scheme Variable} fprintd-service-type
26417 The service type for @command{fprintd}, which provides the fingerprint
26418 reading capability.
26421 (service fprintd-service-type)
26426 @subsubheading System Control Service
26428 The @code{(gnu services sysctl)} provides a service to configure kernel
26429 parameters at boot.
26431 @defvr {Scheme Variable} sysctl-service-type
26432 The service type for @command{sysctl}, which modifies kernel parameters
26433 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
26437 (service sysctl-service-type
26438 (sysctl-configuration
26439 (settings '(("net.ipv4.ip_forward" . "1")))))
26443 @deftp {Data Type} sysctl-configuration
26444 The data type representing the configuration of @command{sysctl}.
26447 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
26448 The @command{sysctl} executable to use.
26450 @item @code{settings} (default: @code{'()})
26451 An association list specifies kernel parameters and their values.
26456 @subsubheading PC/SC Smart Card Daemon Service
26458 The @code{(gnu services security-token)} module provides the following service
26459 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
26460 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
26461 manager that coordinates communications with smart card readers, smart cards
26462 and cryptographic tokens that are connected to the system.
26464 @defvr {Scheme Variable} pcscd-service-type
26465 Service type for the @command{pcscd} service. Its value must be a
26466 @code{pcscd-configuration} object. To run pcscd in the default
26467 configuration, instantiate it as:
26470 (service pcscd-service-type)
26474 @deftp {Data Type} pcscd-configuration
26475 The data type representing the configuration of @command{pcscd}.
26478 @item @code{pcsc-lite} (default: @code{pcsc-lite})
26479 The pcsc-lite package that provides pcscd.
26480 @item @code{usb-drivers} (default: @code{(list ccid)})
26481 List of packages that provide USB drivers to pcscd. Drivers are expected to be
26482 under @file{pcsc/drivers} in the store directory of the package.
26487 @subsubheading Lirc Service
26489 The @code{(gnu services lirc)} module provides the following service.
26491 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
26492 [#:device #f] [#:driver #f] [#:config-file #f] @
26493 [#:extra-options '()]
26494 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
26495 decodes infrared signals from remote controls.
26497 Optionally, @var{device}, @var{driver} and @var{config-file}
26498 (configuration file name) may be specified. See @command{lircd} manual
26501 Finally, @var{extra-options} is a list of additional command-line options
26502 passed to @command{lircd}.
26506 @subsubheading Spice Service
26508 The @code{(gnu services spice)} module provides the following service.
26510 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
26511 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
26512 that enables sharing the clipboard with a vm and setting the guest display
26513 resolution when the graphical console window resizes.
26516 @cindex inputattach
26517 @subsubheading inputattach Service
26519 @cindex tablet input, for Xorg
26520 @cindex touchscreen input, for Xorg
26521 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
26522 use input devices such as Wacom tablets, touchscreens, or joysticks with the
26523 Xorg display server.
26525 @deffn {Scheme Variable} inputattach-service-type
26526 Type of a service that runs @command{inputattach} on a device and
26527 dispatches events from it.
26530 @deftp {Data Type} inputattach-configuration
26532 @item @code{device-type} (default: @code{"wacom"})
26533 The type of device to connect to. Run @command{inputattach --help}, from the
26534 @code{inputattach} package, to see the list of supported device types.
26536 @item @code{device} (default: @code{"/dev/ttyS0"})
26537 The device file to connect to the device.
26539 @item @code{baud-rate} (default: @code{#f})
26540 Baud rate to use for the serial connection.
26541 Should be a number or @code{#f}.
26543 @item @code{log-file} (default: @code{#f})
26544 If true, this must be the name of a file to log messages to.
26548 @subsubheading Dictionary Service
26550 The @code{(gnu services dict)} module provides the following service:
26552 @defvr {Scheme Variable} dicod-service-type
26553 This is the type of the service that runs the @command{dicod} daemon, an
26554 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
26557 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
26558 Return a service that runs the @command{dicod} daemon, an implementation
26559 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
26561 The optional @var{config} argument specifies the configuration for
26562 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
26563 default it serves the GNU Collaborative International Dictionary of English.
26565 You can add @command{open localhost} to your @file{~/.dico} file to make
26566 @code{localhost} the default server for @command{dico} client
26567 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
26570 @deftp {Data Type} dicod-configuration
26571 Data type representing the configuration of dicod.
26574 @item @code{dico} (default: @var{dico})
26575 Package object of the GNU Dico dictionary server.
26577 @item @code{interfaces} (default: @var{'("localhost")})
26578 This is the list of IP addresses and ports and possibly socket file
26579 names to listen to (@pxref{Server Settings, @code{listen} directive,,
26580 dico, GNU Dico Manual}).
26582 @item @code{handlers} (default: @var{'()})
26583 List of @code{<dicod-handler>} objects denoting handlers (module instances).
26585 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
26586 List of @code{<dicod-database>} objects denoting dictionaries to be served.
26590 @deftp {Data Type} dicod-handler
26591 Data type representing a dictionary handler (module instance).
26595 Name of the handler (module instance).
26597 @item @code{module} (default: @var{#f})
26598 Name of the dicod module of the handler (instance). If it is @code{#f},
26599 the module has the same name as the handler.
26600 (@pxref{Modules,,, dico, GNU Dico Manual}).
26602 @item @code{options}
26603 List of strings or gexps representing the arguments for the module handler
26607 @deftp {Data Type} dicod-database
26608 Data type representing a dictionary database.
26612 Name of the database, will be used in DICT commands.
26614 @item @code{handler}
26615 Name of the dicod handler (module instance) used by this database
26616 (@pxref{Handlers,,, dico, GNU Dico Manual}).
26618 @item @code{complex?} (default: @var{#f})
26619 Whether the database configuration complex. The complex configuration
26620 will need a corresponding @code{<dicod-handler>} object, otherwise not.
26622 @item @code{options}
26623 List of strings or gexps representing the arguments for the database
26624 (@pxref{Databases,,, dico, GNU Dico Manual}).
26628 @defvr {Scheme Variable} %dicod-database:gcide
26629 A @code{<dicod-database>} object serving the GNU Collaborative International
26630 Dictionary of English using the @code{gcide} package.
26633 The following is an example @code{dicod-service} configuration.
26636 (dicod-service #:config
26637 (dicod-configuration
26638 (handlers (list (dicod-handler
26642 (list #~(string-append "dbdir=" #$wordnet))))))
26643 (databases (list (dicod-database
26646 (handler "wordnet")
26647 (options '("database=wn")))
26648 %dicod-database:gcide))))
26652 @subsubheading Docker Service
26654 The @code{(gnu services docker)} module provides the following services.
26656 @defvr {Scheme Variable} docker-service-type
26658 This is the type of the service that runs @url{https://www.docker.com,Docker},
26659 a daemon that can execute application bundles (sometimes referred to as
26660 ``containers'') in isolated environments.
26664 @deftp {Data Type} docker-configuration
26665 This is the data type representing the configuration of Docker and Containerd.
26669 @item @code{package} (default: @code{docker})
26670 The Docker package to use.
26672 @item @code{containerd} (default: @var{containerd})
26673 The Containerd package to use.
26675 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
26676 The Docker user-land networking proxy package to use.
26678 @item @code{enable-proxy?} (default @code{#f})
26679 Enable or disable the use of the Docker user-land networking proxy.
26681 @item @code{debug?} (default @code{#f})
26682 Enable or disable debug output.
26688 @subsubheading Auditd Service
26690 The @code{(gnu services auditd)} module provides the following service.
26692 @defvr {Scheme Variable} auditd-service-type
26694 This is the type of the service that runs
26695 @url{https://people.redhat.com/sgrubb/audit/,auditd},
26696 a daemon that tracks security-relevant information on your system.
26698 Examples of things that can be tracked:
26708 Failed login attempts
26715 @command{auditctl} from the @code{audit} package can be used in order
26716 to add or remove events to be tracked (until the next reboot).
26717 In order to permanently track events, put the command line arguments
26718 of auditctl into @file{/etc/audit/audit.rules}.
26719 @command{aureport} from the @code{audit} package can be used in order
26720 to view a report of all recorded events.
26721 The audit daemon usually logs into the directory @file{/var/log/audit}.
26725 @deftp {Data Type} auditd-configuration
26726 This is the data type representing the configuration of auditd.
26730 @item @code{audit} (default: @code{audit})
26731 The audit package to use.
26736 @defvr {Scheme Variable} singularity-service-type
26737 This is the type of the service that allows you to run
26738 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
26739 create and run application bundles (aka. ``containers''). The value for this
26740 service is the Singularity package to use.
26742 The service does not install a daemon; instead, it installs helper programs as
26743 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
26744 @command{singularity run} and similar commands.
26748 @subsubheading R-Shiny service
26750 The @code{(gnu services science)} module provides the following service.
26752 @defvr {Scheme Variable} rshiny-service-type
26754 This is a type of service which is used to run a webapp created with
26755 @code{r-shiny}. This service sets the @code{R_LIBS_USER} environment
26756 variable and runs the provided script to call @code{runApp}.
26758 @deftp {Data Type} rshiny-configuration
26759 This is the data type representing the configuration of rshiny.
26763 @item @code{package} (default: @code{r-shiny})
26764 The package to use.
26766 @item @code{binary} (defaunlt @code{"rshiny"})
26767 The name of the binary or shell script located at @code{package/bin/} to
26768 run when the service is run.
26770 The common way to create this file is as follows:
26774 (let* ((out (assoc-ref %outputs "out"))
26775 (targetdir (string-append out "/share/" ,name))
26776 (app (string-append out "/bin/" ,name))
26777 (Rbin (string-append (assoc-ref %build-inputs "r-min")
26780 (mkdir-p (string-append out "/bin"))
26781 (call-with-output-file app
26787 runApp(launch.browser=0, port=4202)~%\n"
26797 @subsubheading Nix service
26799 The @code{(gnu services nix)} module provides the following service.
26801 @defvr {Scheme Variable} nix-service-type
26803 This is the type of the service that runs build daemon of the
26804 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
26808 (use-modules (gnu))
26809 (use-service-modules nix)
26810 (use-package-modules package-management)
26814 (packages (append (list nix)
26817 (services (append (list (service nix-service-type))
26821 After @command{guix system reconfigure} configure Nix for your user:
26824 @item Add a Nix channel and update it. See
26825 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
26827 @item Create a symlink to your profile and activate Nix profile:
26831 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
26832 $ source /run/current-system/profile/etc/profile.d/nix.sh
26837 @node Setuid Programs
26838 @section Setuid Programs
26840 @cindex setuid programs
26841 Some programs need to run with ``root'' privileges, even when they are
26842 launched by unprivileged users. A notorious example is the
26843 @command{passwd} program, which users can run to change their
26844 password, and which needs to access the @file{/etc/passwd} and
26845 @file{/etc/shadow} files---something normally restricted to root, for
26846 obvious security reasons. To address that, these executables are
26847 @dfn{setuid-root}, meaning that they always run with root privileges
26848 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
26849 for more info about the setuid mechanism).
26851 The store itself @emph{cannot} contain setuid programs: that would be a
26852 security issue since any user on the system can write derivations that
26853 populate the store (@pxref{The Store}). Thus, a different mechanism is
26854 used: instead of changing the setuid bit directly on files that are in
26855 the store, we let the system administrator @emph{declare} which programs
26856 should be setuid root.
26858 The @code{setuid-programs} field of an @code{operating-system}
26859 declaration contains a list of G-expressions denoting the names of
26860 programs to be setuid-root (@pxref{Using the Configuration System}).
26861 For instance, the @command{passwd} program, which is part of the Shadow
26862 package, can be designated by this G-expression (@pxref{G-Expressions}):
26865 #~(string-append #$shadow "/bin/passwd")
26868 A default set of setuid programs is defined by the
26869 @code{%setuid-programs} variable of the @code{(gnu system)} module.
26871 @defvr {Scheme Variable} %setuid-programs
26872 A list of G-expressions denoting common programs that are setuid-root.
26874 The list includes commands such as @command{passwd}, @command{ping},
26875 @command{su}, and @command{sudo}.
26878 Under the hood, the actual setuid programs are created in the
26879 @file{/run/setuid-programs} directory at system activation time. The
26880 files in this directory refer to the ``real'' binaries, which are in the
26883 @node X.509 Certificates
26884 @section X.509 Certificates
26886 @cindex HTTPS, certificates
26887 @cindex X.509 certificates
26889 Web servers available over HTTPS (that is, HTTP over the transport-layer
26890 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
26891 that the client can then use to @emph{authenticate} the server. To do
26892 that, clients verify that the server's certificate is signed by a
26893 so-called @dfn{certificate authority} (CA). But to verify the CA's
26894 signature, clients must have first acquired the CA's certificate.
26896 Web browsers such as GNU@tie{}IceCat include their own set of CA
26897 certificates, such that they are able to verify CA signatures
26900 However, most other programs that can talk HTTPS---@command{wget},
26901 @command{git}, @command{w3m}, etc.---need to be told where CA
26902 certificates can be found.
26904 @cindex @code{nss-certs}
26905 In Guix, this is done by adding a package that provides certificates
26906 to the @code{packages} field of the @code{operating-system} declaration
26907 (@pxref{operating-system Reference}). Guix includes one such package,
26908 @code{nss-certs}, which is a set of CA certificates provided as part of
26909 Mozilla's Network Security Services.
26911 Note that it is @emph{not} part of @code{%base-packages}, so you need to
26912 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
26913 most applications and libraries look for certificates by default, points
26914 to the certificates installed globally.
26916 Unprivileged users, including users of Guix on a foreign distro,
26917 can also install their own certificate package in
26918 their profile. A number of environment variables need to be defined so
26919 that applications and libraries know where to find them. Namely, the
26920 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
26921 variables. Some applications add their own environment variables; for
26922 instance, the Git version control system honors the certificate bundle
26923 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
26924 would typically run something like:
26927 guix install nss-certs
26928 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
26929 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
26930 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
26933 As another example, R requires the @env{CURL_CA_BUNDLE} environment
26934 variable to point to a certificate bundle, so you would have to run
26935 something like this:
26938 guix install nss-certs
26939 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
26942 For other applications you may want to look up the required environment
26943 variable in the relevant documentation.
26946 @node Name Service Switch
26947 @section Name Service Switch
26949 @cindex name service switch
26951 The @code{(gnu system nss)} module provides bindings to the
26952 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
26953 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
26954 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
26955 extended with new ``name'' lookup methods for system databases, which
26956 includes host names, service names, user accounts, and more (@pxref{Name
26957 Service Switch, System Databases and Name Service Switch,, libc, The GNU
26958 C Library Reference Manual}).
26960 The NSS configuration specifies, for each system database, which lookup
26961 method is to be used, and how the various methods are chained
26962 together---for instance, under which circumstances NSS should try the
26963 next method in the list. The NSS configuration is given in the
26964 @code{name-service-switch} field of @code{operating-system} declarations
26965 (@pxref{operating-system Reference, @code{name-service-switch}}).
26968 @cindex .local, host name lookup
26969 As an example, the declaration below configures the NSS to use the
26970 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
26971 back-end}, which supports host name lookups over multicast DNS (mDNS)
26972 for host names ending in @code{.local}:
26975 (name-service-switch
26976 (hosts (list %files ;first, check /etc/hosts
26978 ;; If the above did not succeed, try
26979 ;; with 'mdns_minimal'.
26981 (name "mdns_minimal")
26983 ;; 'mdns_minimal' is authoritative for
26984 ;; '.local'. When it returns "not found",
26985 ;; no need to try the next methods.
26986 (reaction (lookup-specification
26987 (not-found => return))))
26989 ;; Then fall back to DNS.
26993 ;; Finally, try with the "full" 'mdns'.
26998 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
26999 contains this configuration, so you will not have to type it if all you
27000 want is to have @code{.local} host lookup working.
27002 Note that, in this case, in addition to setting the
27003 @code{name-service-switch} of the @code{operating-system} declaration,
27004 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
27005 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
27006 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
27007 to the name service cache daemon (@pxref{Base Services,
27008 @code{nscd-service}}).
27010 For convenience, the following variables provide typical NSS
27013 @defvr {Scheme Variable} %default-nss
27014 This is the default name service switch configuration, a
27015 @code{name-service-switch} object.
27018 @defvr {Scheme Variable} %mdns-host-lookup-nss
27019 This is the name service switch configuration with support for host name
27020 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
27023 The reference for name service switch configuration is given below. It
27024 is a direct mapping of the configuration file format of the C library , so
27025 please refer to the C library manual for more information (@pxref{NSS
27026 Configuration File,,, libc, The GNU C Library Reference Manual}).
27027 Compared to the configuration file format of libc NSS, it has the advantage
27028 not only of adding this warm parenthetic feel that we like, but also
27029 static checks: you will know about syntax errors and typos as soon as you
27030 run @command{guix system}.
27032 @deftp {Data Type} name-service-switch
27034 This is the data type representation the configuration of libc's name
27035 service switch (NSS). Each field below represents one of the supported
27052 The system databases handled by the NSS. Each of these fields must be a
27053 list of @code{<name-service>} objects (see below).
27057 @deftp {Data Type} name-service
27059 This is the data type representing an actual name service and the
27060 associated lookup action.
27064 A string denoting the name service (@pxref{Services in the NSS
27065 configuration,,, libc, The GNU C Library Reference Manual}).
27067 Note that name services listed here must be visible to nscd. This is
27068 achieved by passing the @code{#:name-services} argument to
27069 @code{nscd-service} the list of packages providing the needed name
27070 services (@pxref{Base Services, @code{nscd-service}}).
27073 An action specified using the @code{lookup-specification} macro
27074 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
27075 Reference Manual}). For example:
27078 (lookup-specification (unavailable => continue)
27079 (success => return))
27084 @node Initial RAM Disk
27085 @section Initial RAM Disk
27088 @cindex initial RAM disk
27089 For bootstrapping purposes, the Linux-Libre kernel is passed an
27090 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
27091 root file system as well as an initialization script. The latter is
27092 responsible for mounting the real root file system, and for loading any
27093 kernel modules that may be needed to achieve that.
27095 The @code{initrd-modules} field of an @code{operating-system}
27096 declaration allows you to specify Linux-libre kernel modules that must
27097 be available in the initrd. In particular, this is where you would list
27098 modules needed to actually drive the hard disk where your root partition
27099 is---although the default value of @code{initrd-modules} should cover
27100 most use cases. For example, assuming you need the @code{megaraid_sas}
27101 module in addition to the default modules to be able to access your root
27102 file system, you would write:
27107 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
27110 @defvr {Scheme Variable} %base-initrd-modules
27111 This is the list of kernel modules included in the initrd by default.
27114 Furthermore, if you need lower-level customization, the @code{initrd}
27115 field of an @code{operating-system} declaration allows
27116 you to specify which initrd you would like to use. The @code{(gnu
27117 system linux-initrd)} module provides three ways to build an initrd: the
27118 high-level @code{base-initrd} procedure and the low-level
27119 @code{raw-initrd} and @code{expression->initrd} procedures.
27121 The @code{base-initrd} procedure is intended to cover most common uses.
27122 For example, if you want to add a bunch of kernel modules to be loaded
27123 at boot time, you can define the @code{initrd} field of the operating
27124 system declaration like this:
27127 (initrd (lambda (file-systems . rest)
27128 ;; Create a standard initrd but set up networking
27129 ;; with the parameters QEMU expects by default.
27130 (apply base-initrd file-systems
27131 #:qemu-networking? #t
27135 The @code{base-initrd} procedure also handles common use cases that
27136 involves using the system as a QEMU guest, or as a ``live'' system with
27137 volatile root file system.
27139 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
27140 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
27141 such as trying to guess which kernel modules and packages should be included
27142 to the initrd. An example use of @code{raw-initrd} is when a user has
27143 a custom Linux kernel configuration and default kernel modules included by
27144 @code{base-initrd} are not available.
27146 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
27147 honors several options passed on the Linux kernel command line
27148 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
27149 @code{-append} option of QEMU), notably:
27152 @item --load=@var{boot}
27153 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
27154 program, once it has mounted the root file system.
27156 Guix uses this option to yield control to a boot program that runs the
27157 service activation programs and then spawns the GNU@tie{}Shepherd, the
27158 initialization system.
27160 @item --root=@var{root}
27161 Mount @var{root} as the root file system. @var{root} can be a device
27162 name like @code{/dev/sda1}, a file system label, or a file system UUID.
27163 When unspecified, the device name from the root file system of the
27164 operating system declaration is used.
27166 @item --system=@var{system}
27167 Have @file{/run/booted-system} and @file{/run/current-system} point to
27170 @item modprobe.blacklist=@var{modules}@dots{}
27171 @cindex module, black-listing
27172 @cindex black list, of kernel modules
27173 Instruct the initial RAM disk as well as the @command{modprobe} command
27174 (from the kmod package) to refuse to load @var{modules}. @var{modules}
27175 must be a comma-separated list of module names---e.g.,
27176 @code{usbkbd,9pnet}.
27179 Start a read-eval-print loop (REPL) from the initial RAM disk before it
27180 tries to load kernel modules and to mount the root file system. Our
27181 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
27182 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
27183 Manual}, for more information on Guile's REPL.
27187 Now that you know all the features that initial RAM disks produced by
27188 @code{base-initrd} and @code{raw-initrd} provide,
27189 here is how to use it and customize it further.
27192 @cindex initial RAM disk
27193 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
27194 [#:linux-modules '()] [#:mapped-devices '()] @
27195 [#:keyboard-layout #f] @
27196 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
27197 Return a derivation that builds a raw initrd. @var{file-systems} is
27198 a list of file systems to be mounted by the initrd, possibly in addition to
27199 the root file system specified on the kernel command line via @option{--root}.
27200 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
27201 @var{mapped-devices} is a list of device mappings to realize before
27202 @var{file-systems} are mounted (@pxref{Mapped Devices}).
27203 @var{helper-packages} is a list of packages to be copied in the initrd. It may
27204 include @code{e2fsck/static} or other packages needed by the initrd to check
27205 the root file system.
27207 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
27208 the desired console keyboard layout. This is done before @var{mapped-devices}
27209 are set up and before @var{file-systems} are mounted such that, should the
27210 user need to enter a passphrase or use the REPL, this happens using the
27211 intended keyboard layout.
27213 When @var{qemu-networking?} is true, set up networking with the standard QEMU
27214 parameters. When @var{virtio?} is true, load additional modules so that the
27215 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
27217 When @var{volatile-root?} is true, the root file system is writable but any changes
27221 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
27222 [#:mapped-devices '()] [#:keyboard-layout #f] @
27223 [#:qemu-networking? #f] [#:volatile-root? #f] @
27224 [#:linux-modules '()]
27225 Return as a file-like object a generic initrd, with kernel
27226 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
27227 mounted by the initrd, possibly in addition to the root file system specified
27228 on the kernel command line via @option{--root}. @var{mapped-devices} is a list of device
27229 mappings to realize before @var{file-systems} are mounted.
27231 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
27232 the desired console keyboard layout. This is done before @var{mapped-devices}
27233 are set up and before @var{file-systems} are mounted such that, should the
27234 user need to enter a passphrase or use the REPL, this happens using the
27235 intended keyboard layout.
27237 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
27239 The initrd is automatically populated with all the kernel modules necessary
27240 for @var{file-systems} and for the given options. Additional kernel
27241 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
27242 loaded at boot time in the order in which they appear.
27245 Needless to say, the initrds we produce and use embed a
27246 statically-linked Guile, and the initialization program is a Guile
27247 program. That gives a lot of flexibility. The
27248 @code{expression->initrd} procedure builds such an initrd, given the
27249 program to run in that initrd.
27251 @deffn {Scheme Procedure} expression->initrd @var{exp} @
27252 [#:guile %guile-3.0-static-stripped] [#:name "guile-initrd"]
27253 Return as a file-like object a Linux initrd (a gzipped cpio archive)
27254 containing @var{guile} and that evaluates @var{exp}, a G-expression,
27255 upon booting. All the derivations referenced by @var{exp} are
27256 automatically copied to the initrd.
27259 @node Bootloader Configuration
27260 @section Bootloader Configuration
27263 @cindex boot loader
27265 The operating system supports multiple bootloaders. The bootloader is
27266 configured using @code{bootloader-configuration} declaration. All the
27267 fields of this structure are bootloader agnostic except for one field,
27268 @code{bootloader} that indicates the bootloader to be configured and
27271 Some of the bootloaders do not honor every field of
27272 @code{bootloader-configuration}. For instance, the extlinux
27273 bootloader does not support themes and thus ignores the @code{theme}
27276 @deftp {Data Type} bootloader-configuration
27277 The type of a bootloader configuration declaration.
27281 @item @code{bootloader}
27282 @cindex EFI, bootloader
27283 @cindex UEFI, bootloader
27284 @cindex BIOS, bootloader
27285 The bootloader to use, as a @code{bootloader} object. For now
27286 @code{grub-bootloader}, @code{grub-efi-bootloader},
27287 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
27289 @vindex grub-efi-bootloader
27290 @code{grub-efi-bootloader} allows to boot on modern systems using the
27291 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
27292 use if the installation image contains a @file{/sys/firmware/efi} directory
27293 when you boot it on your system.
27295 @vindex grub-bootloader
27296 @code{grub-bootloader} allows you to boot in particular Intel-based machines
27297 in ``legacy'' BIOS mode.
27299 @cindex ARM, bootloaders
27300 @cindex AArch64, bootloaders
27301 Available bootloaders are described in @code{(gnu bootloader @dots{})}
27302 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
27303 of bootloaders for a wide range of ARM and AArch64 systems, using the
27304 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
27306 @item @code{target}
27307 This is a string denoting the target onto which to install the
27310 The interpretation depends on the bootloader in question. For
27311 @code{grub-bootloader}, for example, it should be a device name understood by
27312 the bootloader @command{installer} command, such as @code{/dev/sda} or
27313 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
27314 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
27315 system, usually @file{/boot/efi}.
27317 @item @code{menu-entries} (default: @code{()})
27318 A possibly empty list of @code{menu-entry} objects (see below), denoting
27319 entries to appear in the bootloader menu, in addition to the current
27320 system entry and the entry pointing to previous system generations.
27322 @item @code{default-entry} (default: @code{0})
27323 The index of the default boot menu entry. Index 0 is for the entry of the
27326 @item @code{timeout} (default: @code{5})
27327 The number of seconds to wait for keyboard input before booting. Set to
27328 0 to boot immediately, and to -1 to wait indefinitely.
27330 @cindex keyboard layout, for the bootloader
27331 @item @code{keyboard-layout} (default: @code{#f})
27332 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
27333 layout, usually US@tie{}English (``qwerty'').
27335 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
27339 This option is currently ignored by bootloaders other than @code{grub} and
27343 @item @code{theme} (default: @var{#f})
27344 The bootloader theme object describing the theme to use. If no theme
27345 is provided, some bootloaders might use a default theme, that's true
27348 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
27349 The output terminals used for the bootloader boot menu, as a list of
27350 symbols. GRUB accepts the values: @code{console}, @code{serial},
27351 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
27352 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
27353 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
27354 configuration,,, grub,GNU GRUB manual}).
27356 @item @code{terminal-inputs} (default: @code{'()})
27357 The input terminals used for the bootloader boot menu, as a list of
27358 symbols. For GRUB, the default is the native platform terminal as
27359 determined at run-time. GRUB accepts the values: @code{console},
27360 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
27361 @code{usb_keyboard}. This field corresponds to the GRUB variable
27362 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
27365 @item @code{serial-unit} (default: @code{#f})
27366 The serial unit used by the bootloader, as an integer from 0 to 3.
27367 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
27368 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
27370 @item @code{serial-speed} (default: @code{#f})
27371 The speed of the serial interface, as an integer. For GRUB, the
27372 default value is chosen at run-time; currently GRUB chooses
27373 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
27380 Should you want to list additional boot menu entries @i{via} the
27381 @code{menu-entries} field above, you will need to create them with the
27382 @code{menu-entry} form. For example, imagine you want to be able to
27383 boot another distro (hard to imagine!), you can define a menu entry
27388 (label "The Other Distro")
27389 (linux "/boot/old/vmlinux-2.6.32")
27390 (linux-arguments '("root=/dev/sda2"))
27391 (initrd "/boot/old/initrd"))
27396 @deftp {Data Type} menu-entry
27397 The type of an entry in the bootloader menu.
27402 The label to show in the menu---e.g., @code{"GNU"}.
27404 @item @code{linux} (default: @code{#f})
27405 The Linux kernel image to boot, for example:
27408 (file-append linux-libre "/bzImage")
27411 For GRUB, it is also possible to specify a device explicitly in the
27412 file path using GRUB's device naming convention (@pxref{Naming
27413 convention,,, grub, GNU GRUB manual}), for example:
27416 "(hd0,msdos1)/boot/vmlinuz"
27419 If the device is specified explicitly as above, then the @code{device}
27420 field is ignored entirely.
27422 @item @code{linux-arguments} (default: @code{()})
27423 The list of extra Linux kernel command-line arguments---e.g.,
27424 @code{("console=ttyS0")}.
27426 @item @code{initrd} (default: @code{#f})
27427 A G-Expression or string denoting the file name of the initial RAM disk
27428 to use (@pxref{G-Expressions}).
27430 @item @code{device} (default: @code{#f})
27431 The device where the kernel and initrd are to be found---i.e., for GRUB,
27432 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
27434 This may be a file system label (a string), a file system UUID (a
27435 bytevector, @pxref{File Systems}), or @code{#f}, in which case
27436 the bootloader will search the device containing the file specified by
27437 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
27438 must @emph{not} be an OS device name such as @file{/dev/sda1}.
27440 @item @code{multiboot-kernel} (default: @code{#f})
27441 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
27442 manual}). When this field is set, a Multiboot menu-entry is generated.
27446 (file-append mach "/boot/gnumach")
27449 @item @code{multiboot-arguments} (default: @code{()})
27450 The list of extra command-line arguments for the multiboot-kernel.
27452 @item @code{multiboot-modules} (default: @code{()})
27453 The list of commands for loading Multiboot modules. For example:
27456 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
27458 (list (file-append libc "/lib/ld.so.1") "exec"
27468 @c FIXME: Write documentation once it's stable.
27469 For now only GRUB has theme support. GRUB themes are created using
27470 the @code{grub-theme} form, which is not fully documented yet.
27472 @deftp {Data Type} grub-theme
27473 Data type representing the configuration of the GRUB theme.
27476 @item @code{gfxmode} (default: @code{'("auto")})
27477 The GRUB @code{gfxmode} to set (a list of screen resolution strings, see
27478 @pxref{gfxmode,,, grub, GNU GRUB manual}).
27482 @deffn {Scheme Procedure} grub-theme
27483 Return the default GRUB theme used by the operating system if no
27484 @code{theme} field is specified in @code{bootloader-configuration}
27487 It comes with a fancy background image displaying the GNU and Guix
27491 For example, to override the default resolution, you may use something
27496 (bootloader-configuration
27499 (inherit (grub-theme))
27500 (gfxmode '("1024x786x32" "auto"))))))
27503 @node Invoking guix system
27504 @section Invoking @code{guix system}
27506 Once you have written an operating system declaration as seen in the
27507 previous section, it can be @dfn{instantiated} using the @command{guix
27508 system} command. The synopsis is:
27511 guix system @var{options}@dots{} @var{action} @var{file}
27514 @var{file} must be the name of a file containing an
27515 @code{operating-system} declaration. @var{action} specifies how the
27516 operating system is instantiated. Currently the following values are
27521 Display available service type definitions that match the given regular
27522 expressions, sorted by relevance:
27528 $ guix system search console
27529 name: console-fonts
27530 location: gnu/services/base.scm:806:2
27531 extends: shepherd-root
27532 description: Install the given fonts on the specified ttys (fonts are per
27533 + virtual console on GNU/Linux). The value of this service is a list of
27534 + tty/font pairs. The font can be the name of a font provided by the `kbd'
27535 + package or any valid argument to `setfont', as in this example:
27537 + '(("tty1" . "LatGrkCyr-8x16")
27538 + ("tty2" . (file-append
27540 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
27541 + ("tty3" . (file-append
27543 + "/share/consolefonts/ter-132n"))) ; for HDPI
27547 location: gnu/services/base.scm:1190:2
27548 extends: shepherd-root
27549 description: Provide console login using the `mingetty' program.
27553 location: gnu/services/base.scm:860:2
27555 description: Provide a console log-in service as specified by its
27556 + configuration value, a `login-configuration' object.
27562 As for @command{guix package --search}, the result is written in
27563 @code{recutils} format, which makes it easy to filter the output
27564 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
27567 Build the operating system described in @var{file}, activate it, and
27568 switch to it@footnote{This action (and the related actions
27569 @code{switch-generation} and @code{roll-back}) are usable only on
27570 systems already running Guix System.}.
27573 @c The paragraph below refers to the problem discussed at
27574 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
27575 It is highly recommended to run @command{guix pull} once before you run
27576 @command{guix system reconfigure} for the first time (@pxref{Invoking
27577 guix pull}). Failing to do that you would see an older version of Guix
27578 once @command{reconfigure} has completed.
27581 This effects all the configuration specified in @var{file}: user
27582 accounts, system services, global package list, setuid programs, etc.
27583 The command starts system services specified in @var{file} that are not
27584 currently running; if a service is currently running this command will
27585 arrange for it to be upgraded the next time it is stopped (e.g.@: by
27586 @code{herd stop X} or @code{herd restart X}).
27588 This command creates a new generation whose number is one greater than
27589 the current generation (as reported by @command{guix system
27590 list-generations}). If that generation already exists, it will be
27591 overwritten. This behavior mirrors that of @command{guix package}
27592 (@pxref{Invoking guix package}).
27594 It also adds a bootloader menu entry for the new OS configuration,
27595 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
27596 entries for older configurations to a submenu, allowing you to choose
27597 an older system generation at boot time should you need it.
27599 @cindex provenance tracking, of the operating system
27600 Upon completion, the new system is deployed under
27601 @file{/run/current-system}. This directory contains @dfn{provenance
27602 meta-data}: the list of channels in use (@pxref{Channels}) and
27603 @var{file} itself, when available. This information is useful should
27604 you later want to inspect how this particular generation was built.
27606 In fact, assuming @var{file} is self-contained, you can later rebuild
27607 generation @var{n} of your operating system with:
27610 guix time-machine \
27611 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
27612 system reconfigure \
27613 /var/guix/profiles/system-@var{n}-link/configuration.scm
27616 You can think of it as some sort of built-in version control! Your
27617 system is not just a binary artifact: @emph{it carries its own source}.
27618 @xref{Service Reference, @code{provenance-service-type}}, for more
27619 information on provenance tracking.
27621 @item switch-generation
27622 @cindex generations
27623 Switch to an existing system generation. This action atomically
27624 switches the system profile to the specified system generation. It
27625 also rearranges the system's existing bootloader menu entries. It
27626 makes the menu entry for the specified system generation the default,
27627 and it moves the entries for the other generations to a submenu, if
27628 supported by the bootloader being used. The next time the system
27629 boots, it will use the specified system generation.
27631 The bootloader itself is not being reinstalled when using this
27632 command. Thus, the installed bootloader is used with an updated
27633 configuration file.
27635 The target generation can be specified explicitly by its generation
27636 number. For example, the following invocation would switch to system
27640 guix system switch-generation 7
27643 The target generation can also be specified relative to the current
27644 generation with the form @code{+N} or @code{-N}, where @code{+3} means
27645 ``3 generations ahead of the current generation,'' and @code{-1} means
27646 ``1 generation prior to the current generation.'' When specifying a
27647 negative value such as @code{-1}, you must precede it with @code{--} to
27648 prevent it from being parsed as an option. For example:
27651 guix system switch-generation -- -1
27654 Currently, the effect of invoking this action is @emph{only} to switch
27655 the system profile to an existing generation and rearrange the
27656 bootloader menu entries. To actually start using the target system
27657 generation, you must reboot after running this action. In the future,
27658 it will be updated to do the same things as @command{reconfigure},
27659 like activating and deactivating services.
27661 This action will fail if the specified generation does not exist.
27664 @cindex rolling back
27665 Switch to the preceding system generation. The next time the system
27666 boots, it will use the preceding system generation. This is the inverse
27667 of @command{reconfigure}, and it is exactly the same as invoking
27668 @command{switch-generation} with an argument of @code{-1}.
27670 Currently, as with @command{switch-generation}, you must reboot after
27671 running this action to actually start using the preceding system
27674 @item delete-generations
27675 @cindex deleting system generations
27676 @cindex saving space
27677 Delete system generations, making them candidates for garbage collection
27678 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
27681 This works in the same way as @samp{guix package --delete-generations}
27682 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
27683 arguments, all system generations but the current one are deleted:
27686 guix system delete-generations
27689 You can also select the generations you want to delete. The example below
27690 deletes all the system generations that are more than two month old:
27693 guix system delete-generations 2m
27696 Running this command automatically reinstalls the bootloader with an updated
27697 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
27698 longer lists the generations that have been deleted.
27701 Build the derivation of the operating system, which includes all the
27702 configuration files and programs needed to boot and run the system.
27703 This action does not actually install anything.
27706 Populate the given directory with all the files necessary to run the
27707 operating system specified in @var{file}. This is useful for first-time
27708 installations of Guix System. For instance:
27711 guix system init my-os-config.scm /mnt
27714 copies to @file{/mnt} all the store items required by the configuration
27715 specified in @file{my-os-config.scm}. This includes configuration
27716 files, packages, and so on. It also creates other essential files
27717 needed for the system to operate correctly---e.g., the @file{/etc},
27718 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
27720 This command also installs bootloader on the target specified in
27721 @file{my-os-config}, unless the @option{--no-bootloader} option was
27725 @cindex virtual machine
27727 @anchor{guix system vm}
27728 Build a virtual machine that contains the operating system declared in
27729 @var{file}, and return a script to run that virtual machine (VM).
27732 The @code{vm} action and others below
27733 can use KVM support in the Linux-libre kernel. Specifically, if the
27734 machine has hardware virtualization support, the corresponding
27735 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
27736 must exist and be readable and writable by the user and by the
27737 build users of the daemon (@pxref{Build Environment Setup}).
27740 Arguments given to the script are passed to QEMU as in the example
27741 below, which enables networking and requests 1@tie{}GiB of RAM for the
27745 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
27748 The VM shares its store with the host system.
27750 Additional file systems can be shared between the host and the VM using
27751 the @option{--share} and @option{--expose} command-line options: the former
27752 specifies a directory to be shared with write access, while the latter
27753 provides read-only access to the shared directory.
27755 The example below creates a VM in which the user's home directory is
27756 accessible read-only, and where the @file{/exchange} directory is a
27757 read-write mapping of @file{$HOME/tmp} on the host:
27760 guix system vm my-config.scm \
27761 --expose=$HOME --share=$HOME/tmp=/exchange
27764 On GNU/Linux, the default is to boot directly to the kernel; this has
27765 the advantage of requiring only a very tiny root disk image since the
27766 store of the host can then be mounted.
27768 The @option{--full-boot} option forces a complete boot sequence, starting
27769 with the bootloader. This requires more disk space since a root image
27770 containing at least the kernel, initrd, and bootloader data files must
27771 be created. The @option{--image-size} option can be used to specify the
27774 @cindex System images, creation in various formats
27775 @cindex Creating system images in various formats
27778 @itemx docker-image
27779 Return a virtual machine, disk image, or Docker image of the operating
27780 system declared in @var{file} that stands alone. By default,
27781 @command{guix system} estimates the size of the image needed to store
27782 the system, but you can use the @option{--image-size} option to specify
27783 a value. Docker images are built to contain exactly what they need, so
27784 the @option{--image-size} option is ignored in the case of
27785 @code{docker-image}.
27787 You can specify the root file system type by using the
27788 @option{--file-system-type} option. It defaults to @code{ext4}.
27790 When using @code{vm-image}, the returned image is in qcow2 format, which
27791 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
27792 for more information on how to run the image in a virtual machine.
27794 When using @code{disk-image}, a raw disk image is produced; it can be
27795 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
27796 the device corresponding to a USB stick, one can copy the image to it
27797 using the following command:
27800 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc status=progress
27803 When using @code{docker-image}, a Docker image is produced. Guix builds
27804 the image from scratch, not from a pre-existing Docker base image. As a
27805 result, it contains @emph{exactly} what you define in the operating
27806 system configuration file. You can then load the image and launch a
27807 Docker container using commands like the following:
27810 image_id="`docker load < guix-system-docker-image.tar.gz`"
27811 container_id="`docker create $image_id`"
27812 docker start $container_id
27815 This command starts a new Docker container from the specified image. It
27816 will boot the Guix system in the usual manner, which means it will
27817 start any services you have defined in the operating system
27818 configuration. You can get an interactive shell running in the container
27819 using @command{docker exec}:
27822 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
27825 Depending on what you run in the Docker container, it
27826 may be necessary to give the container additional permissions. For
27827 example, if you intend to build software using Guix inside of the Docker
27828 container, you may need to pass the @option{--privileged} option to
27829 @code{docker create}.
27831 Last, the @option{--network} option applies to @command{guix system
27832 docker-image}: it produces an image where network is supposedly shared
27833 with the host, and thus without services like nscd or NetworkManager.
27836 Return a script to run the operating system declared in @var{file}
27837 within a container. Containers are a set of lightweight isolation
27838 mechanisms provided by the kernel Linux-libre. Containers are
27839 substantially less resource-demanding than full virtual machines since
27840 the kernel, shared objects, and other resources can be shared with the
27841 host system; this also means they provide thinner isolation.
27843 Currently, the script must be run as root in order to support more than
27844 a single user and group. The container shares its store with the host
27847 As with the @code{vm} action (@pxref{guix system vm}), additional file
27848 systems to be shared between the host and container can be specified
27849 using the @option{--share} and @option{--expose} options:
27852 guix system container my-config.scm \
27853 --expose=$HOME --share=$HOME/tmp=/exchange
27857 This option requires Linux-libre 3.19 or newer.
27862 @var{options} can contain any of the common build options (@pxref{Common
27863 Build Options}). In addition, @var{options} can contain one of the
27867 @item --expression=@var{expr}
27868 @itemx -e @var{expr}
27869 Consider the operating-system @var{expr} evaluates to.
27870 This is an alternative to specifying a file which evaluates to an
27872 This is used to generate the Guix system installer @pxref{Building the
27873 Installation Image}).
27875 @item --system=@var{system}
27876 @itemx -s @var{system}
27877 Attempt to build for @var{system} instead of the host system type.
27878 This works as per @command{guix build} (@pxref{Invoking guix build}).
27882 Return the derivation file name of the given operating system without
27885 @cindex provenance tracking, of the operating system
27886 @item --save-provenance
27887 As discussed above, @command{guix system init} and @command{guix system
27888 reconfigure} always save provenance information @i{via} a dedicated
27889 service (@pxref{Service Reference, @code{provenance-service-type}}).
27890 However, other commands don't do that by default. If you wish to, say,
27891 create a virtual machine image that contains provenance information, you
27895 guix system vm-image --save-provenance config.scm
27898 That way, the resulting image will effectively ``embed its own source''
27899 in the form of meta-data in @file{/run/current-system}. With that
27900 information, one can rebuild the image to make sure it really contains
27901 what it pretends to contain; or they could use that to derive a variant
27904 @item --file-system-type=@var{type}
27905 @itemx -t @var{type}
27906 For the @code{disk-image} action, create a file system of the given
27907 @var{type} on the image.
27909 When this option is omitted, @command{guix system} uses @code{ext4}.
27911 @cindex ISO-9660 format
27912 @cindex CD image format
27913 @cindex DVD image format
27914 @option{--file-system-type=iso9660} produces an ISO-9660 image, suitable
27915 for burning on CDs and DVDs.
27917 @item --image-size=@var{size}
27918 For the @code{vm-image} and @code{disk-image} actions, create an image
27919 of the given @var{size}. @var{size} may be a number of bytes, or it may
27920 include a unit as a suffix (@pxref{Block size, size specifications,,
27921 coreutils, GNU Coreutils}).
27923 When this option is omitted, @command{guix system} computes an estimate
27924 of the image size as a function of the size of the system declared in
27929 For the @code{container} action, allow containers to access the host network,
27930 that is, do not create a network namespace.
27932 @item --root=@var{file}
27933 @itemx -r @var{file}
27934 Make @var{file} a symlink to the result, and register it as a garbage
27937 @item --skip-checks
27938 Skip pre-installation safety checks.
27940 By default, @command{guix system init} and @command{guix system
27941 reconfigure} perform safety checks: they make sure the file systems that
27942 appear in the @code{operating-system} declaration actually exist
27943 (@pxref{File Systems}), and that any Linux kernel modules that may be
27944 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
27945 RAM Disk}). Passing this option skips these tests altogether.
27948 @cindex on-error strategy
27949 @cindex error strategy
27950 @item --on-error=@var{strategy}
27951 Apply @var{strategy} when an error occurs when reading @var{file}.
27952 @var{strategy} may be one of the following:
27955 @item nothing-special
27956 Report the error concisely and exit. This is the default strategy.
27959 Likewise, but also display a backtrace.
27962 Report the error and enter Guile's debugger. From there, you can run
27963 commands such as @code{,bt} to get a backtrace, @code{,locals} to
27964 display local variable values, and more generally inspect the state of the
27965 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
27966 a list of available debugging commands.
27970 Once you have built, configured, re-configured, and re-re-configured
27971 your Guix installation, you may find it useful to list the operating
27972 system generations available on disk---and that you can choose from the
27973 bootloader boot menu:
27978 Describe the current system generation: its file name, the kernel and
27979 bootloader used, etc., as well as provenance information when available.
27981 @item list-generations
27982 List a summary of each generation of the operating system available on
27983 disk, in a human-readable way. This is similar to the
27984 @option{--list-generations} option of @command{guix package}
27985 (@pxref{Invoking guix package}).
27987 Optionally, one can specify a pattern, with the same syntax that is used
27988 in @command{guix package --list-generations}, to restrict the list of
27989 generations displayed. For instance, the following command displays
27990 generations that are up to 10 days old:
27993 $ guix system list-generations 10d
27998 The @command{guix system} command has even more to offer! The following
27999 sub-commands allow you to visualize how your system services relate to
28002 @anchor{system-extension-graph}
28005 @item extension-graph
28006 Emit in Dot/Graphviz format to standard output the @dfn{service
28007 extension graph} of the operating system defined in @var{file}
28008 (@pxref{Service Composition}, for more information on service
28014 $ guix system extension-graph @var{file} | xdot -
28017 shows the extension relations among services.
28019 @anchor{system-shepherd-graph}
28020 @item shepherd-graph
28021 Emit in Dot/Graphviz format to standard output the @dfn{dependency
28022 graph} of shepherd services of the operating system defined in
28023 @var{file}. @xref{Shepherd Services}, for more information and for an
28028 @node Invoking guix deploy
28029 @section Invoking @code{guix deploy}
28031 We've already seen @code{operating-system} declarations used to manage a
28032 machine's configuration locally. Suppose you need to configure multiple
28033 machines, though---perhaps you're managing a service on the web that's
28034 comprised of several servers. @command{guix deploy} enables you to use those
28035 same @code{operating-system} declarations to manage multiple remote hosts at
28036 once as a logical ``deployment''.
28039 The functionality described in this section is still under development
28040 and is subject to change. Get in touch with us on
28041 @email{guix-devel@@gnu.org}!
28045 guix deploy @var{file}
28048 Such an invocation will deploy the machines that the code within @var{file}
28049 evaluates to. As an example, @var{file} might contain a definition like this:
28052 ;; This is a Guix deployment of a "bare bones" setup, with
28053 ;; no X11 display server, to a machine with an SSH daemon
28054 ;; listening on localhost:2222. A configuration such as this
28055 ;; may be appropriate for virtual machine with ports
28056 ;; forwarded to the host's loopback interface.
28058 (use-service-modules networking ssh)
28059 (use-package-modules bootloaders)
28063 (host-name "gnu-deployed")
28064 (timezone "Etc/UTC")
28065 (bootloader (bootloader-configuration
28066 (bootloader grub-bootloader)
28067 (target "/dev/vda")
28068 (terminal-outputs '(console))))
28069 (file-systems (cons (file-system
28071 (device "/dev/vda1")
28073 %base-file-systems))
28075 (append (list (service dhcp-client-service-type)
28076 (service openssh-service-type
28077 (openssh-configuration
28078 (permit-root-login #t)
28079 (allow-empty-passwords? #t))))
28083 (operating-system %system)
28084 (environment managed-host-environment-type)
28085 (configuration (machine-ssh-configuration
28086 (host-name "localhost")
28087 (system "x86_64-linux")
28089 (identity "./id_rsa")
28093 The file should evaluate to a list of @var{machine} objects. This example,
28094 upon being deployed, will create a new generation on the remote system
28095 realizing the @code{operating-system} declaration @code{%system}.
28096 @code{environment} and @code{configuration} specify how the machine should be
28097 provisioned---that is, how the computing resources should be created and
28098 managed. The above example does not create any resources, as a
28099 @code{'managed-host} is a machine that is already running the Guix system and
28100 available over the network. This is a particularly simple case; a more
28101 complex deployment may involve, for example, starting virtual machines through
28102 a Virtual Private Server (VPS) provider. In such a case, a different
28103 @var{environment} type would be used.
28105 Do note that you first need to generate a key pair on the coordinator machine
28106 to allow the daemon to export signed archives of files from the store
28107 (@pxref{Invoking guix archive}).
28110 # guix archive --generate-key
28114 Each target machine must authorize the key of the master machine so that it
28115 accepts store items it receives from the coordinator:
28118 # guix archive --authorize < coordinator-public-key.txt
28121 @code{user}, in this example, specifies the name of the user account to log in
28122 as to perform the deployment. Its default value is @code{root}, but root
28123 login over SSH may be forbidden in some cases. To work around this,
28124 @command{guix deploy} can log in as an unprivileged user and employ
28125 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
28126 currently installed on the remote and can be invoked non-interactively as
28127 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
28128 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
28129 be accomplished with the following operating system configuration snippet:
28133 (gnu system)) ;for %sudoers-specification
28135 (define %user "username")
28140 (plain-file "sudoers"
28141 (string-append (plain-file-content %sudoers-specification)
28142 (format #f "~a ALL = NOPASSWD: ALL~%"
28147 For more information regarding the format of the @file{sudoers} file,
28148 consult @command{man sudoers}.
28150 @deftp {Data Type} machine
28151 This is the data type representing a single machine in a heterogeneous Guix
28155 @item @code{operating-system}
28156 The object of the operating system configuration to deploy.
28158 @item @code{environment}
28159 An @code{environment-type} describing how the machine should be provisioned.
28161 @item @code{configuration} (default: @code{#f})
28162 An object describing the configuration for the machine's @code{environment}.
28163 If the @code{environment} has a default configuration, @code{#f} may be used.
28164 If @code{#f} is used for an environment with no default configuration,
28165 however, an error will be thrown.
28169 @deftp {Data Type} machine-ssh-configuration
28170 This is the data type representing the SSH client parameters for a machine
28171 with an @code{environment} of @code{managed-host-environment-type}.
28174 @item @code{host-name}
28175 @item @code{build-locally?} (default: @code{#t})
28176 If false, system derivations will be built on the machine being deployed to.
28177 @item @code{system}
28178 The system type describing the architecture of the machine being deployed
28179 to---e.g., @code{"x86_64-linux"}.
28180 @item @code{authorize?} (default: @code{#t})
28181 If true, the coordinator's signing key will be added to the remote's ACL
28183 @item @code{port} (default: @code{22})
28184 @item @code{user} (default: @code{"root"})
28185 @item @code{identity} (default: @code{#f})
28186 If specified, the path to the SSH private key to use to authenticate with the
28189 @item @code{host-key} (default: @code{#f})
28190 This should be the SSH host key of the machine, which looks like this:
28193 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
28196 When @code{host-key} is @code{#f}, the server is authenticated against
28197 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
28203 @deftp {Data Type} digital-ocean-configuration
28204 This is the data type describing the Droplet that should be created for a
28205 machine with an @code{environment} of @code{digital-ocean-environment-type}.
28208 @item @code{ssh-key}
28209 The path to the SSH private key to use to authenticate with the remote
28210 host. In the future, this field may not exist.
28212 A list of string ``tags'' that uniquely identify the machine. Must be given
28213 such that no two machines in the deployment have the same set of tags.
28214 @item @code{region}
28215 A Digital Ocean region slug, such as @code{"nyc3"}.
28217 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
28218 @item @code{enable-ipv6?}
28219 Whether or not the droplet should be created with IPv6 networking.
28223 @node Running Guix in a VM
28224 @section Running Guix in a Virtual Machine
28226 @cindex virtual machine
28227 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
28229 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
28230 This image is a compressed image in QCOW format. You will first need to
28231 decompress with @command{xz -d}, and then you can pass it to an emulator such
28232 as QEMU (see below for details).
28234 This image boots the Xfce graphical environment and it contains some
28235 commonly-used tools. You can install more software in the image by running
28236 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
28237 also reconfigure the system based on its initial configuration file available
28238 as @file{/run/current-system/configuration.scm} (@pxref{Using the
28239 Configuration System}).
28241 Instead of using this pre-built image, one can also build their own virtual
28242 machine image using @command{guix system vm-image} (@pxref{Invoking guix
28243 system}). The returned image is in qcow2 format, which the
28244 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
28247 If you built your own image, you must copy it out of the store
28248 (@pxref{The Store}) and give yourself permission to write to the copy
28249 before you can use it. When invoking QEMU, you must choose a system
28250 emulator that is suitable for your hardware platform. Here is a minimal
28251 QEMU invocation that will boot the result of @command{guix system
28252 vm-image} on x86_64 hardware:
28255 $ qemu-system-x86_64 \
28256 -nic user,model=virtio-net-pci \
28257 -enable-kvm -m 1024 \
28258 -device virtio-blk,drive=myhd \
28259 -drive if=none,file=/tmp/qemu-image,id=myhd
28262 Here is what each of these options means:
28265 @item qemu-system-x86_64
28266 This specifies the hardware platform to emulate. This should match the
28269 @item -nic user,model=virtio-net-pci
28270 Enable the unprivileged user-mode network stack. The guest OS can
28271 access the host but not vice versa. This is the simplest way to get the
28272 guest OS online. @code{model} specifies which network device to emulate:
28273 @code{virtio-net-pci} is a special device made for virtualized operating
28274 systems and recommended for most uses. Assuming your hardware platform is
28275 x86_64, you can get a list of available NIC models by running
28276 @command{qemu-system-x86_64 -nic model=help}.
28279 If your system has hardware virtualization extensions, enabling the
28280 virtual machine support (KVM) of the Linux kernel will make things run
28283 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
28285 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
28286 which may be insufficient for some operations.
28288 @item -device virtio-blk,drive=myhd
28289 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
28290 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
28291 better performance than if it were emulating a complete disk drive. See the
28292 QEMU and KVM documentation for more info.
28294 @item -drive if=none,file=/tmp/qemu-image,id=myhd
28295 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
28296 the ``myhd'' drive.
28299 The default @command{run-vm.sh} script that is returned by an invocation of
28300 @command{guix system vm} does not add a @command{-nic user} flag by default.
28301 To get network access from within the vm add the @code{(dhcp-client-service)}
28302 to your system definition and start the VM using
28303 @command{`guix system vm config.scm` -nic user}. An important caveat of using
28304 @command{-nic user} for networking is that @command{ping} will not work, because
28305 it uses the ICMP protocol. You'll have to use a different command to check for
28306 network connectivity, for example @command{guix download}.
28308 @subsection Connecting Through SSH
28312 To enable SSH inside a VM you need to add an SSH server like
28313 @code{openssh-service-type} to your VM (@pxref{Networking Services,
28314 @code{openssh-service-type}}). In addition you need to forward the SSH port,
28315 22 by default, to the host. You can do this with
28318 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
28321 To connect to the VM you can run
28324 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
28327 The @command{-p} tells @command{ssh} the port you want to connect to.
28328 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
28329 every time you modify your @command{config.scm} file and the
28330 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
28331 connection to an unknown host every time you connect.
28333 @subsection Using @command{virt-viewer} with Spice
28335 As an alternative to the default @command{qemu} graphical client you can
28336 use the @command{remote-viewer} from the @command{virt-viewer} package. To
28337 connect pass the @command{-spice port=5930,disable-ticketing} flag to
28338 @command{qemu}. See previous section for further information on how to do this.
28340 Spice also allows you to do some nice stuff like share your clipboard with your
28341 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
28344 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
28345 -chardev spicevmc,name=vdagent,id=vdagent
28346 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
28347 name=com.redhat.spice.0
28350 You'll also need to add the @code{(spice-vdagent-service)} to your
28351 system definition (@pxref{Miscellaneous Services, Spice service}).
28353 @node Defining Services
28354 @section Defining Services
28356 The previous sections show the available services and how one can combine
28357 them in an @code{operating-system} declaration. But how do we define
28358 them in the first place? And what is a service anyway?
28361 * Service Composition:: The model for composing services.
28362 * Service Types and Services:: Types and services.
28363 * Service Reference:: API reference.
28364 * Shepherd Services:: A particular type of service.
28367 @node Service Composition
28368 @subsection Service Composition
28372 Here we define a @dfn{service} as, broadly, something that extends the
28373 functionality of the operating system. Often a service is a process---a
28374 @dfn{daemon}---started when the system boots: a secure shell server, a
28375 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
28376 whose execution can be triggered by another daemon---e.g., an FTP server
28377 started by @command{inetd} or a D-Bus service activated by
28378 @command{dbus-daemon}. Occasionally, a service does not map to a
28379 daemon. For instance, the ``account'' service collects user accounts
28380 and makes sure they exist when the system runs; the ``udev'' service
28381 collects device management rules and makes them available to the eudev
28382 daemon; the @file{/etc} service populates the @file{/etc} directory
28385 @cindex service extensions
28386 Guix system services are connected by @dfn{extensions}. For instance, the
28387 secure shell service @emph{extends} the Shepherd---the
28388 initialization system, running as PID@tie{}1---by giving it the command
28389 lines to start and stop the secure shell daemon (@pxref{Networking
28390 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
28391 service by passing it its @file{.service} specification, and extends the
28392 udev service by passing it device management rules (@pxref{Desktop
28393 Services, @code{upower-service}}); the Guix daemon service extends the
28394 Shepherd by passing it the command lines to start and stop the daemon,
28395 and extends the account service by passing it a list of required build
28396 user accounts (@pxref{Base Services}).
28398 All in all, services and their ``extends'' relations form a directed
28399 acyclic graph (DAG). If we represent services as boxes and extensions
28400 as arrows, a typical system might provide something like this:
28402 @image{images/service-graph,,5in,Typical service extension graph.}
28404 @cindex system service
28405 At the bottom, we see the @dfn{system service}, which produces the
28406 directory containing everything to run and boot the system, as returned
28407 by the @command{guix system build} command. @xref{Service Reference},
28408 to learn about the other service types shown here.
28409 @xref{system-extension-graph, the @command{guix system extension-graph}
28410 command}, for information on how to generate this representation for a
28411 particular operating system definition.
28413 @cindex service types
28414 Technically, developers can define @dfn{service types} to express these
28415 relations. There can be any number of services of a given type on the
28416 system---for instance, a system running two instances of the GNU secure
28417 shell server (lsh) has two instances of @code{lsh-service-type}, with
28418 different parameters.
28420 The following section describes the programming interface for service
28421 types and services.
28423 @node Service Types and Services
28424 @subsection Service Types and Services
28426 A @dfn{service type} is a node in the DAG described above. Let us start
28427 with a simple example, the service type for the Guix build daemon
28428 (@pxref{Invoking guix-daemon}):
28431 (define guix-service-type
28435 (list (service-extension shepherd-root-service-type guix-shepherd-service)
28436 (service-extension account-service-type guix-accounts)
28437 (service-extension activation-service-type guix-activation)))
28438 (default-value (guix-configuration))))
28442 It defines three things:
28446 A name, whose sole purpose is to make inspection and debugging easier.
28449 A list of @dfn{service extensions}, where each extension designates the
28450 target service type and a procedure that, given the parameters of the
28451 service, returns a list of objects to extend the service of that type.
28453 Every service type has at least one service extension. The only
28454 exception is the @dfn{boot service type}, which is the ultimate service.
28457 Optionally, a default value for instances of this type.
28460 In this example, @code{guix-service-type} extends three services:
28463 @item shepherd-root-service-type
28464 The @code{guix-shepherd-service} procedure defines how the Shepherd
28465 service is extended. Namely, it returns a @code{<shepherd-service>}
28466 object that defines how @command{guix-daemon} is started and stopped
28467 (@pxref{Shepherd Services}).
28469 @item account-service-type
28470 This extension for this service is computed by @code{guix-accounts},
28471 which returns a list of @code{user-group} and @code{user-account}
28472 objects representing the build user accounts (@pxref{Invoking
28475 @item activation-service-type
28476 Here @code{guix-activation} is a procedure that returns a gexp, which is
28477 a code snippet to run at ``activation time''---e.g., when the service is
28481 A service of this type is instantiated like this:
28484 (service guix-service-type
28485 (guix-configuration
28487 (use-substitutes? #f)))
28490 The second argument to the @code{service} form is a value representing
28491 the parameters of this specific service instance.
28492 @xref{guix-configuration-type, @code{guix-configuration}}, for
28493 information about the @code{guix-configuration} data type. When the
28494 value is omitted, the default value specified by
28495 @code{guix-service-type} is used:
28498 (service guix-service-type)
28501 @code{guix-service-type} is quite simple because it extends other
28502 services but is not extensible itself.
28504 @c @subsubsubsection Extensible Service Types
28506 The service type for an @emph{extensible} service looks like this:
28509 (define udev-service-type
28510 (service-type (name 'udev)
28512 (list (service-extension shepherd-root-service-type
28513 udev-shepherd-service)))
28515 (compose concatenate) ;concatenate the list of rules
28516 (extend (lambda (config rules)
28518 (($ <udev-configuration> udev initial-rules)
28519 (udev-configuration
28520 (udev udev) ;the udev package to use
28521 (rules (append initial-rules rules)))))))))
28524 This is the service type for the
28525 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
28526 management daemon}. Compared to the previous example, in addition to an
28527 extension of @code{shepherd-root-service-type}, we see two new fields:
28531 This is the procedure to @dfn{compose} the list of extensions to
28532 services of this type.
28534 Services can extend the udev service by passing it lists of rules; we
28535 compose those extensions simply by concatenating them.
28538 This procedure defines how the value of the service is @dfn{extended} with
28539 the composition of the extensions.
28541 Udev extensions are composed into a list of rules, but the udev service
28542 value is itself a @code{<udev-configuration>} record. So here, we
28543 extend that record by appending the list of rules it contains to the
28544 list of contributed rules.
28547 This is a string giving an overview of the service type. The string can
28548 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
28549 @command{guix system search} command searches these strings and displays
28550 them (@pxref{Invoking guix system}).
28553 There can be only one instance of an extensible service type such as
28554 @code{udev-service-type}. If there were more, the
28555 @code{service-extension} specifications would be ambiguous.
28557 Still here? The next section provides a reference of the programming
28558 interface for services.
28560 @node Service Reference
28561 @subsection Service Reference
28563 We have seen an overview of service types (@pxref{Service Types and
28564 Services}). This section provides a reference on how to manipulate
28565 services and service types. This interface is provided by the
28566 @code{(gnu services)} module.
28568 @deffn {Scheme Procedure} service @var{type} [@var{value}]
28569 Return a new service of @var{type}, a @code{<service-type>} object (see
28570 below). @var{value} can be any object; it represents the parameters of
28571 this particular service instance.
28573 When @var{value} is omitted, the default value specified by @var{type}
28574 is used; if @var{type} does not specify a default value, an error is
28577 For instance, this:
28580 (service openssh-service-type)
28584 is equivalent to this:
28587 (service openssh-service-type
28588 (openssh-configuration))
28591 In both cases the result is an instance of @code{openssh-service-type}
28592 with the default configuration.
28595 @deffn {Scheme Procedure} service? @var{obj}
28596 Return true if @var{obj} is a service.
28599 @deffn {Scheme Procedure} service-kind @var{service}
28600 Return the type of @var{service}---i.e., a @code{<service-type>} object.
28603 @deffn {Scheme Procedure} service-value @var{service}
28604 Return the value associated with @var{service}. It represents its
28608 Here is an example of how a service is created and manipulated:
28612 (service nginx-service-type
28613 (nginx-configuration
28615 (log-directory log-directory)
28616 (run-directory run-directory)
28617 (file config-file))))
28622 (eq? (service-kind s) nginx-service-type)
28626 The @code{modify-services} form provides a handy way to change the
28627 parameters of some of the services of a list such as
28628 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
28629 evaluates to a list of services. Of course, you could always use
28630 standard list combinators such as @code{map} and @code{fold} to do that
28631 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
28632 @code{modify-services} simply provides a more concise form for this
28635 @deffn {Scheme Syntax} modify-services @var{services} @
28636 (@var{type} @var{variable} => @var{body}) @dots{}
28638 Modify the services listed in @var{services} according to the given
28639 clauses. Each clause has the form:
28642 (@var{type} @var{variable} => @var{body})
28645 where @var{type} is a service type---e.g.,
28646 @code{guix-service-type}---and @var{variable} is an identifier that is
28647 bound within the @var{body} to the service parameters---e.g., a
28648 @code{guix-configuration} instance---of the original service of that
28651 The @var{body} should evaluate to the new service parameters, which will
28652 be used to configure the new service. This new service will replace the
28653 original in the resulting list. Because a service's service parameters
28654 are created using @code{define-record-type*}, you can write a succinct
28655 @var{body} that evaluates to the new service parameters by using the
28656 @code{inherit} feature that @code{define-record-type*} provides.
28658 @xref{Using the Configuration System}, for example usage.
28662 Next comes the programming interface for service types. This is
28663 something you want to know when writing new service definitions, but not
28664 necessarily when simply looking for ways to customize your
28665 @code{operating-system} declaration.
28667 @deftp {Data Type} service-type
28668 @cindex service type
28669 This is the representation of a @dfn{service type} (@pxref{Service Types
28674 This is a symbol, used only to simplify inspection and debugging.
28676 @item @code{extensions}
28677 A non-empty list of @code{<service-extension>} objects (see below).
28679 @item @code{compose} (default: @code{#f})
28680 If this is @code{#f}, then the service type denotes services that cannot
28681 be extended---i.e., services that do not receive ``values'' from other
28684 Otherwise, it must be a one-argument procedure. The procedure is called
28685 by @code{fold-services} and is passed a list of values collected from
28686 extensions. It may return any single value.
28688 @item @code{extend} (default: @code{#f})
28689 If this is @code{#f}, services of this type cannot be extended.
28691 Otherwise, it must be a two-argument procedure: @code{fold-services}
28692 calls it, passing it the initial value of the service as the first
28693 argument and the result of applying @code{compose} to the extension
28694 values as the second argument. It must return a value that is a valid
28695 parameter value for the service instance.
28698 @xref{Service Types and Services}, for examples.
28701 @deffn {Scheme Procedure} service-extension @var{target-type} @
28703 Return a new extension for services of type @var{target-type}.
28704 @var{compute} must be a one-argument procedure: @code{fold-services}
28705 calls it, passing it the value associated with the service that provides
28706 the extension; it must return a valid value for the target service.
28709 @deffn {Scheme Procedure} service-extension? @var{obj}
28710 Return true if @var{obj} is a service extension.
28713 Occasionally, you might want to simply extend an existing service. This
28714 involves creating a new service type and specifying the extension of
28715 interest, which can be verbose; the @code{simple-service} procedure
28716 provides a shorthand for this.
28718 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
28719 Return a service that extends @var{target} with @var{value}. This works
28720 by creating a singleton service type @var{name}, of which the returned
28721 service is an instance.
28723 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
28727 (simple-service 'my-mcron-job mcron-service-type
28728 #~(job '(next-hour (3)) "guix gc -F 2G"))
28732 At the core of the service abstraction lies the @code{fold-services}
28733 procedure, which is responsible for ``compiling'' a list of services
28734 down to a single directory that contains everything needed to boot and
28735 run the system---the directory shown by the @command{guix system build}
28736 command (@pxref{Invoking guix system}). In essence, it propagates
28737 service extensions down the service graph, updating each node parameters
28738 on the way, until it reaches the root node.
28740 @deffn {Scheme Procedure} fold-services @var{services} @
28741 [#:target-type @var{system-service-type}]
28742 Fold @var{services} by propagating their extensions down to the root of
28743 type @var{target-type}; return the root service adjusted accordingly.
28746 Lastly, the @code{(gnu services)} module also defines several essential
28747 service types, some of which are listed below.
28749 @defvr {Scheme Variable} system-service-type
28750 This is the root of the service graph. It produces the system directory
28751 as returned by the @command{guix system build} command.
28754 @defvr {Scheme Variable} boot-service-type
28755 The type of the ``boot service'', which produces the @dfn{boot script}.
28756 The boot script is what the initial RAM disk runs when booting.
28759 @defvr {Scheme Variable} etc-service-type
28760 The type of the @file{/etc} service. This service is used to create
28761 files under @file{/etc} and can be extended by
28762 passing it name/file tuples such as:
28765 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
28768 In this example, the effect would be to add an @file{/etc/issue} file
28769 pointing to the given file.
28772 @defvr {Scheme Variable} setuid-program-service-type
28773 Type for the ``setuid-program service''. This service collects lists of
28774 executable file names, passed as gexps, and adds them to the set of
28775 setuid-root programs on the system (@pxref{Setuid Programs}).
28778 @defvr {Scheme Variable} profile-service-type
28779 Type of the service that populates the @dfn{system profile}---i.e., the
28780 programs under @file{/run/current-system/profile}. Other services can
28781 extend it by passing it lists of packages to add to the system profile.
28784 @cindex provenance tracking, of the operating system
28785 @defvr {Scheme Variable} provenance-service-type
28786 This is the type of the service that records @dfn{provenance meta-data}
28787 in the system itself. It creates several files under
28788 @file{/run/current-system}:
28792 This is a ``channel file'' that can be passed to @command{guix pull -C}
28793 or @command{guix time-machine -C}, and which describes the channels used
28794 to build the system, if that information was available
28795 (@pxref{Channels}).
28797 @item configuration.scm
28798 This is the file that was passed as the value for this
28799 @code{provenance-service-type} service. By default, @command{guix
28800 system reconfigure} automatically passes the OS configuration file it
28801 received on the command line.
28804 This contains the same information as the two other files but in a
28805 format that is more readily processable.
28808 In general, these two pieces of information (channels and configuration
28809 file) are enough to reproduce the operating system ``from source''.
28812 This information is necessary to rebuild your operating system, but it
28813 is not always sufficient. In particular, @file{configuration.scm}
28814 itself is insufficient if it is not self-contained---if it refers to
28815 external Guile modules or to extra files. If you want
28816 @file{configuration.scm} to be self-contained, we recommend that modules
28817 or files it refers to be part of a channel.
28819 Besides, provenance meta-data is ``silent'' in the sense that it does
28820 not change the bits contained in your system, @emph{except for the
28821 meta-data bits themselves}. Two different OS configurations or sets of
28822 channels can lead to the same system, bit-for-bit; when
28823 @code{provenance-service-type} is used, these two systems will have
28824 different meta-data and thus different store file names, which makes
28825 comparison less trivial.
28828 This service is automatically added to your operating system
28829 configuration when you use @command{guix system reconfigure},
28830 @command{guix system init}, or @command{guix deploy}.
28833 @node Shepherd Services
28834 @subsection Shepherd Services
28836 @cindex shepherd services
28838 @cindex init system
28839 The @code{(gnu services shepherd)} module provides a way to define
28840 services managed by the GNU@tie{}Shepherd, which is the
28841 initialization system---the first process that is started when the
28842 system boots, also known as PID@tie{}1
28843 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
28845 Services in the Shepherd can depend on each other. For instance, the
28846 SSH daemon may need to be started after the syslog daemon has been
28847 started, which in turn can only happen once all the file systems have
28848 been mounted. The simple operating system defined earlier (@pxref{Using
28849 the Configuration System}) results in a service graph like this:
28851 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
28853 You can actually generate such a graph for any operating system
28854 definition using the @command{guix system shepherd-graph} command
28855 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
28857 The @code{%shepherd-root-service} is a service object representing
28858 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
28859 by passing it lists of @code{<shepherd-service>} objects.
28861 @deftp {Data Type} shepherd-service
28862 The data type representing a service managed by the Shepherd.
28865 @item @code{provision}
28866 This is a list of symbols denoting what the service provides.
28868 These are the names that may be passed to @command{herd start},
28869 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
28870 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
28871 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
28873 @item @code{requirement} (default: @code{'()})
28874 List of symbols denoting the Shepherd services this one depends on.
28876 @cindex one-shot services, for the Shepherd
28877 @item @code{one-shot?} (default: @code{#f})
28878 Whether this service is @dfn{one-shot}. One-shot services stop immediately
28879 after their @code{start} action has completed. @xref{Slots of services,,,
28880 shepherd, The GNU Shepherd Manual}, for more info.
28882 @item @code{respawn?} (default: @code{#t})
28883 Whether to restart the service when it stops, for instance when the
28884 underlying process dies.
28887 @itemx @code{stop} (default: @code{#~(const #f)})
28888 The @code{start} and @code{stop} fields refer to the Shepherd's
28889 facilities to start and stop processes (@pxref{Service De- and
28890 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
28891 G-expressions that get expanded in the Shepherd configuration file
28892 (@pxref{G-Expressions}).
28894 @item @code{actions} (default: @code{'()})
28895 @cindex actions, of Shepherd services
28896 This is a list of @code{shepherd-action} objects (see below) defining
28897 @dfn{actions} supported by the service, in addition to the standard
28898 @code{start} and @code{stop} actions. Actions listed here become available as
28899 @command{herd} sub-commands:
28902 herd @var{action} @var{service} [@var{arguments}@dots{}]
28905 @item @code{auto-start?} (default: @code{#t})
28906 Whether this service should be started automatically by the Shepherd. If it
28907 is @code{#f} the service has to be started manually with @code{herd start}.
28909 @item @code{documentation}
28910 A documentation string, as shown when running:
28913 herd doc @var{service-name}
28916 where @var{service-name} is one of the symbols in @code{provision}
28917 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
28919 @item @code{modules} (default: @code{%default-modules})
28920 This is the list of modules that must be in scope when @code{start} and
28921 @code{stop} are evaluated.
28926 @deftp {Data Type} shepherd-action
28927 This is the data type that defines additional actions implemented by a
28928 Shepherd service (see above).
28932 Symbol naming the action.
28934 @item documentation
28935 This is a documentation string for the action. It can be viewed by running:
28938 herd doc @var{service} action @var{action}
28942 This should be a gexp that evaluates to a procedure of at least one argument,
28943 which is the ``running value'' of the service (@pxref{Slots of services,,,
28944 shepherd, The GNU Shepherd Manual}).
28947 The following example defines an action called @code{say-hello} that kindly
28953 (documentation "Say hi!")
28954 (procedure #~(lambda (running . args)
28955 (format #t "Hello, friend! arguments: ~s\n"
28960 Assuming this action is added to the @code{example} service, then you can do:
28963 # herd say-hello example
28964 Hello, friend! arguments: ()
28965 # herd say-hello example a b c
28966 Hello, friend! arguments: ("a" "b" "c")
28969 This, as you can see, is a fairly sophisticated way to say hello.
28970 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
28974 @defvr {Scheme Variable} shepherd-root-service-type
28975 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
28977 This is the service type that extensions target when they want to create
28978 shepherd services (@pxref{Service Types and Services}, for an example).
28979 Each extension must pass a list of @code{<shepherd-service>}.
28982 @defvr {Scheme Variable} %shepherd-root-service
28983 This service represents PID@tie{}1.
28987 @node Documentation
28988 @chapter Documentation
28990 @cindex documentation, searching for
28991 @cindex searching for documentation
28992 @cindex Info, documentation format
28994 @cindex manual pages
28995 In most cases packages installed with Guix come with documentation.
28996 There are two main documentation formats: ``Info'', a browseable
28997 hypertext format used for GNU software, and ``manual pages'' (or ``man
28998 pages''), the linear documentation format traditionally found on Unix.
28999 Info manuals are accessed with the @command{info} command or with Emacs,
29000 and man pages are accessed using @command{man}.
29002 You can look for documentation of software installed on your system by
29003 keyword. For example, the following command searches for information
29004 about ``TLS'' in Info manuals:
29008 "(emacs)Network Security" -- STARTTLS
29009 "(emacs)Network Security" -- TLS
29010 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
29011 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
29016 The command below searches for the same keyword in man pages:
29020 SSL (7) - OpenSSL SSL/TLS library
29021 certtool (1) - GnuTLS certificate tool
29025 These searches are purely local to your computer so you have the
29026 guarantee that documentation you find corresponds to what you have
29027 actually installed, you can access it off-line, and your privacy is
29030 Once you have these results, you can view the relevant documentation by
29034 $ info "(gnutls)Core TLS API"
29044 Info manuals contain sections and indices as well as hyperlinks like
29045 those found in Web pages. The @command{info} reader (@pxref{Top, Info
29046 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
29047 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
29048 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
29049 Introduction}, for an introduction to Info navigation.
29051 @node Installing Debugging Files
29052 @chapter Installing Debugging Files
29054 @cindex debugging files
29055 Program binaries, as produced by the GCC compilers for instance, are
29056 typically written in the ELF format, with a section containing
29057 @dfn{debugging information}. Debugging information is what allows the
29058 debugger, GDB, to map binary code to source code; it is required to
29059 debug a compiled program in good conditions.
29061 The problem with debugging information is that is takes up a fair amount
29062 of disk space. For example, debugging information for the GNU C Library
29063 weighs in at more than 60 MiB. Thus, as a user, keeping all the
29064 debugging info of all the installed programs is usually not an option.
29065 Yet, space savings should not come at the cost of an impediment to
29066 debugging---especially in the GNU system, which should make it easier
29067 for users to exert their computing freedom (@pxref{GNU Distribution}).
29069 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
29070 mechanism that allows users to get the best of both worlds: debugging
29071 information can be stripped from the binaries and stored in separate
29072 files. GDB is then able to load debugging information from those files,
29073 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
29076 The GNU distribution takes advantage of this by storing debugging
29077 information in the @code{lib/debug} sub-directory of a separate package
29078 output unimaginatively called @code{debug} (@pxref{Packages with
29079 Multiple Outputs}). Users can choose to install the @code{debug} output
29080 of a package when they need it. For instance, the following command
29081 installs the debugging information for the GNU C Library and for GNU
29085 guix install glibc:debug guile:debug
29088 GDB must then be told to look for debug files in the user's profile, by
29089 setting the @code{debug-file-directory} variable (consider setting it
29090 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
29094 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
29097 From there on, GDB will pick up debugging information from the
29098 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
29100 In addition, you will most likely want GDB to be able to show the source
29101 code being debugged. To do that, you will have to unpack the source
29102 code of the package of interest (obtained with @code{guix build
29103 --source}, @pxref{Invoking guix build}), and to point GDB to that source
29104 directory using the @code{directory} command (@pxref{Source Path,
29105 @code{directory},, gdb, Debugging with GDB}).
29107 @c XXX: keep me up-to-date
29108 The @code{debug} output mechanism in Guix is implemented by the
29109 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
29110 opt-in---debugging information is available only for the packages
29111 with definitions explicitly declaring a @code{debug} output. This may be
29112 changed to opt-out in the future if our build farm servers can handle
29113 the load. To check whether a package has a @code{debug} output, use
29114 @command{guix package --list-available} (@pxref{Invoking guix package}).
29117 @node Security Updates
29118 @chapter Security Updates
29120 @cindex security updates
29121 @cindex security vulnerabilities
29122 Occasionally, important security vulnerabilities are discovered in software
29123 packages and must be patched. Guix developers try hard to keep track of
29124 known vulnerabilities and to apply fixes as soon as possible in the
29125 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
29126 containing only security updates). The @command{guix lint} tool helps
29127 developers find out about vulnerable versions of software packages in the
29132 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
29133 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
29134 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
29138 @xref{Invoking guix lint}, for more information.
29140 Guix follows a functional
29141 package management discipline (@pxref{Introduction}), which implies
29142 that, when a package is changed, @emph{every package that depends on it}
29143 must be rebuilt. This can significantly slow down the deployment of
29144 fixes in core packages such as libc or Bash, since basically the whole
29145 distribution would need to be rebuilt. Using pre-built binaries helps
29146 (@pxref{Substitutes}), but deployment may still take more time than
29150 To address this, Guix implements @dfn{grafts}, a mechanism that allows
29151 for fast deployment of critical updates without the costs associated
29152 with a whole-distribution rebuild. The idea is to rebuild only the
29153 package that needs to be patched, and then to ``graft'' it onto packages
29154 explicitly installed by the user and that were previously referring to
29155 the original package. The cost of grafting is typically very low, and
29156 order of magnitudes lower than a full rebuild of the dependency chain.
29158 @cindex replacements of packages, for grafts
29159 For instance, suppose a security update needs to be applied to Bash.
29160 Guix developers will provide a package definition for the ``fixed''
29161 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
29162 Packages}). Then, the original package definition is augmented with a
29163 @code{replacement} field pointing to the package containing the bug fix:
29170 (replacement bash-fixed)))
29173 From there on, any package depending directly or indirectly on Bash---as
29174 reported by @command{guix gc --requisites} (@pxref{Invoking guix
29175 gc})---that is installed is automatically ``rewritten'' to refer to
29176 @code{bash-fixed} instead of @code{bash}. This grafting process takes
29177 time proportional to the size of the package, usually less than a
29178 minute for an ``average'' package on a recent machine. Grafting is
29179 recursive: when an indirect dependency requires grafting, then grafting
29180 ``propagates'' up to the package that the user is installing.
29182 Currently, the length of the name and version of the graft and that of
29183 the package it replaces (@code{bash-fixed} and @code{bash} in the example
29184 above) must be equal. This restriction mostly comes from the fact that
29185 grafting works by patching files, including binary files, directly.
29186 Other restrictions may apply: for instance, when adding a graft to a
29187 package providing a shared library, the original shared library and its
29188 replacement must have the same @code{SONAME} and be binary-compatible.
29190 The @option{--no-grafts} command-line option allows you to forcefully
29191 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
29195 guix build bash --no-grafts
29199 returns the store file name of the original Bash, whereas:
29206 returns the store file name of the ``fixed'', replacement Bash. This
29207 allows you to distinguish between the two variants of Bash.
29209 To verify which Bash your whole profile refers to, you can run
29210 (@pxref{Invoking guix gc}):
29213 guix gc -R `readlink -f ~/.guix-profile` | grep bash
29217 @dots{} and compare the store file names that you get with those above.
29218 Likewise for a complete Guix system generation:
29221 guix gc -R `guix system build my-config.scm` | grep bash
29224 Lastly, to check which Bash running processes are using, you can use the
29225 @command{lsof} command:
29228 lsof | grep /gnu/store/.*bash
29232 @node Bootstrapping
29233 @chapter Bootstrapping
29235 @c Adapted from the ELS 2013 paper.
29237 @cindex bootstrapping
29239 Bootstrapping in our context refers to how the distribution gets built
29240 ``from nothing''. Remember that the build environment of a derivation
29241 contains nothing but its declared inputs (@pxref{Introduction}). So
29242 there's an obvious chicken-and-egg problem: how does the first package
29243 get built? How does the first compiler get compiled? Note that this is
29244 a question of interest only to the curious hacker, not to the regular
29245 user, so you can shamelessly skip this section if you consider yourself
29246 a ``regular user''.
29248 @cindex bootstrap binaries
29249 The GNU system is primarily made of C code, with libc at its core. The
29250 GNU build system itself assumes the availability of a Bourne shell and
29251 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
29252 `grep'. Furthermore, build programs---programs that run
29253 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
29254 (@pxref{Derivations}). Consequently, to be able to build anything at
29255 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
29256 Binutils, libc, and the other packages mentioned above---the
29257 @dfn{bootstrap binaries}.
29259 These bootstrap binaries are ``taken for granted'', though we can also
29260 re-create them if needed (@pxref{Preparing to Use the Bootstrap
29264 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
29265 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
29268 @node Reduced Binary Seed Bootstrap
29269 @section The Reduced Binary Seed Bootstrap
29271 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
29272 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
29273 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
29274 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
29275 ``taken for granted.''
29277 Taking the bootstrap binaries for granted means that we consider them to
29278 be a correct and trustworthy ``seed'' for building the complete system.
29279 Therein lies a problem: the combined size of these bootstrap binaries is
29280 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
29281 or even inspecting these is next to impossible.
29283 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
29284 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
29285 Source Bootstrap'' and while we are working towards that goal it would
29286 be hyperbole to use that term for what we do now.}.
29288 The Reduced Binary Seed bootstrap removes the most critical tools---from a
29289 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
29290 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
29291 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
29292 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
29294 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
29295 C Library are built from source. From here on the more traditional
29296 bootstrap process resumes. This approach has reduced the bootstrap
29297 binaries in size to about 145MB in Guix v1.1.
29299 The next step that Guix has taken is to replace the shell and all its
29300 utilities with implementations in Guile Scheme, the @emph{Scheme-only
29301 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
29302 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
29303 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
29304 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
29305 removed are now built from source.
29307 Building the GNU System from source is currently only possibly by adding
29308 some historical GNU packages as intermediate steps@footnote{Packages
29309 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
29310 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
29311 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
29312 and GNU packages become more bootstrappable again (e.g., new releases of
29313 GNU Sed will also ship as gzipped tarballs again, as alternative to the
29314 hard to bootstrap @code{xz}-compression), this set of added packages can
29315 hopefully be reduced again.
29317 The graph below shows the resulting dependency graph for
29318 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
29319 traditional bootstrap of the rest of the Guix System.
29321 @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
29322 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
29324 The only significant binary bootstrap seeds that remain@footnote{
29325 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
29326 together with @code{mes}.} are a Scheme intepreter and a Scheme
29327 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
29328 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
29329 to get Guile running.}.
29331 This further reduction has brought down the size of the binary seed to
29332 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
29334 Work is ongoing to remove all binary blobs from our free software
29335 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
29336 is work to bring these bootstraps to the @code{arm-linux} and
29337 @code{aarch64-linux} architectures and to the Hurd.
29339 If you are interested, join us on @samp{#bootstrappable} on the Freenode
29340 IRC network or discuss on @email{bug-mes@@gnu.org} or
29341 @email{gash-devel@@nongnu.org}.
29343 @node Preparing to Use the Bootstrap Binaries
29344 @section Preparing to Use the Bootstrap Binaries
29346 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
29347 @c large image, it's hard to scroll. Oh well.
29348 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
29350 The figure above shows the very beginning of the dependency graph of the
29351 distribution, corresponding to the package definitions of the @code{(gnu
29352 packages bootstrap)} module. A similar figure can be generated with
29353 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
29356 guix graph -t derivation \
29357 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
29358 | dot -Tps > gcc.ps
29361 or, for the further Reduced Binary Seed bootstrap
29364 guix graph -t derivation \
29365 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
29366 | dot -Tps > mes.ps
29369 At this level of detail, things are
29370 slightly complex. First, Guile itself consists of an ELF executable,
29371 along with many source and compiled Scheme files that are dynamically
29372 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
29373 tarball shown in this graph. This tarball is part of Guix's ``source''
29374 distribution, and gets inserted into the store with @code{add-to-store}
29375 (@pxref{The Store}).
29377 But how do we write a derivation that unpacks this tarball and adds it
29378 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
29379 derivation---the first one that gets built---uses @code{bash} as its
29380 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
29381 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
29382 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
29383 the Guix source distribution, whose sole purpose is to allow the Guile
29384 tarball to be unpacked.
29386 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
29387 Guile that can be used to run subsequent build programs. Its first task
29388 is to download tarballs containing the other pre-built binaries---this
29389 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
29390 @code{ftp-client.scm} are used for this purpose. The
29391 @code{module-import.drv} derivations import those modules in a directory
29392 in the store, using the original layout. The
29393 @code{module-import-compiled.drv} derivations compile those modules, and
29394 write them in an output directory with the right layout. This
29395 corresponds to the @code{#:modules} argument of
29396 @code{build-expression->derivation} (@pxref{Derivations}).
29398 Finally, the various tarballs are unpacked by the derivations
29399 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
29400 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
29401 point we have a working C tool chain.
29403 @unnumberedsec Building the Build Tools
29405 Bootstrapping is complete when we have a full tool chain that does not
29406 depend on the pre-built bootstrap tools discussed above. This
29407 no-dependency requirement is verified by checking whether the files of
29408 the final tool chain contain references to the @file{/gnu/store}
29409 directories of the bootstrap inputs. The process that leads to this
29410 ``final'' tool chain is described by the package definitions found in
29411 the @code{(gnu packages commencement)} module.
29413 The @command{guix graph} command allows us to ``zoom out'' compared to
29414 the graph above, by looking at the level of package objects instead of
29415 individual derivations---remember that a package may translate to
29416 several derivations, typically one derivation to download its source,
29417 one to build the Guile modules it needs, and one to actually build the
29418 package from source. The command:
29421 guix graph -t bag \
29422 -e '(@@@@ (gnu packages commencement)
29423 glibc-final-with-bootstrap-bash)' | xdot -
29427 displays the dependency graph leading to the ``final'' C
29428 library@footnote{You may notice the @code{glibc-intermediate} label,
29429 suggesting that it is not @emph{quite} final, but as a good
29430 approximation, we will consider it final.}, depicted below.
29432 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
29434 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
29435 The first tool that gets built with the bootstrap binaries is
29436 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
29437 for all the following packages. From there Findutils and Diffutils get
29440 Then come the first-stage Binutils and GCC, built as pseudo cross
29441 tools---i.e., with @option{--target} equal to @option{--host}. They are
29442 used to build libc. Thanks to this cross-build trick, this libc is
29443 guaranteed not to hold any reference to the initial tool chain.
29445 From there the final Binutils and GCC (not shown above) are built. GCC
29446 uses @command{ld} from the final Binutils, and links programs against
29447 the just-built libc. This tool chain is used to build the other
29448 packages used by Guix and by the GNU Build System: Guile, Bash,
29451 And voilà! At this point we have the complete set of build tools that
29452 the GNU Build System expects. These are in the @code{%final-inputs}
29453 variable of the @code{(gnu packages commencement)} module, and are
29454 implicitly used by any package that uses @code{gnu-build-system}
29455 (@pxref{Build Systems, @code{gnu-build-system}}).
29458 @unnumberedsec Building the Bootstrap Binaries
29460 @cindex bootstrap binaries
29461 Because the final tool chain does not depend on the bootstrap binaries,
29462 those rarely need to be updated. Nevertheless, it is useful to have an
29463 automated way to produce them, should an update occur, and this is what
29464 the @code{(gnu packages make-bootstrap)} module provides.
29466 The following command builds the tarballs containing the bootstrap binaries
29467 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
29468 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
29469 and Guile, and a tarball containing a mixture of Coreutils and other basic
29470 command-line tools):
29473 guix build bootstrap-tarballs
29476 The generated tarballs are those that should be referred to in the
29477 @code{(gnu packages bootstrap)} module mentioned at the beginning of
29480 Still here? Then perhaps by now you've started to wonder: when do we
29481 reach a fixed point? That is an interesting question! The answer is
29482 unknown, but if you would like to investigate further (and have
29483 significant computational and storage resources to do so), then let us
29486 @unnumberedsec Reducing the Set of Bootstrap Binaries
29488 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
29489 binary code! Why is that a problem? It's a problem because these big chunks
29490 of binary code are practically non-auditable, which makes it hard to establish
29491 what source code produced them. Every unauditable binary also leaves us
29492 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
29493 paper @emph{Reflections on Trusting Trust}.
29495 This is mitigated by the fact that our bootstrap binaries were generated
29496 from an earlier Guix revision. Nevertheless it lacks the level of
29497 transparency that we get in the rest of the package dependency graph,
29498 where Guix always gives us a source-to-binary mapping. Thus, our goal
29499 is to reduce the set of bootstrap binaries to the bare minimum.
29501 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
29502 on-going projects to do that. One of these is about replacing the
29503 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
29504 of increasing complexity, which could be built from source starting from
29505 a simple and auditable assembler.
29507 Our first major achievement is the replacement of of GCC, the GNU C Library
29508 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
29509 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
29510 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
29511 bootstrapped yet and thus we inject them as binary seeds. We call this the
29512 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
29513 binaries! Also, it has eliminated the C compiler binary; i686-linux and
29514 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
29516 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
29517 also looking at any other bootstrap binaries. Your help is welcome!
29520 @chapter Porting to a New Platform
29522 As discussed above, the GNU distribution is self-contained, and
29523 self-containment is achieved by relying on pre-built ``bootstrap
29524 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
29525 operating system kernel, CPU architecture, and application binary
29526 interface (ABI). Thus, to port the distribution to a platform that is
29527 not yet supported, one must build those bootstrap binaries, and update
29528 the @code{(gnu packages bootstrap)} module to use them on that platform.
29530 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
29531 When everything goes well, and assuming the GNU tool chain supports the
29532 target platform, this can be as simple as running a command like this
29536 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
29539 For this to work, the @code{glibc-dynamic-linker} procedure in
29540 @code{(gnu packages bootstrap)} must be augmented to return the right
29541 file name for libc's dynamic linker on that platform; likewise,
29542 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
29543 taught about the new platform.
29545 Once these are built, the @code{(gnu packages bootstrap)} module needs
29546 to be updated to refer to these binaries on the target platform. That
29547 is, the hashes and URLs of the bootstrap tarballs for the new platform
29548 must be added alongside those of the currently supported platforms. The
29549 bootstrap Guile tarball is treated specially: it is expected to be
29550 available locally, and @file{gnu/local.mk} has rules to download it for
29551 the supported architectures; a rule for the new platform must be added
29554 In practice, there may be some complications. First, it may be that the
29555 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
29556 above) is not recognized by all the GNU tools. Typically, glibc
29557 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
29558 configure flag (see @code{gcc.scm} for examples of how to handle this).
29559 Second, some of the required packages could fail to build for that
29560 platform. Lastly, the generated binaries could be broken for some
29563 @c *********************************************************************
29564 @include contributing.texi
29566 @c *********************************************************************
29567 @node Acknowledgments
29568 @chapter Acknowledgments
29570 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
29571 which was designed and
29572 implemented by Eelco Dolstra, with contributions from other people (see
29573 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
29574 management, and promoted unprecedented features, such as transactional
29575 package upgrades and rollbacks, per-user profiles, and referentially
29576 transparent build processes. Without this work, Guix would not exist.
29578 The Nix-based software distributions, Nixpkgs and NixOS, have also been
29579 an inspiration for Guix.
29581 GNU@tie{}Guix itself is a collective work with contributions from a
29582 number of people. See the @file{AUTHORS} file in Guix for more
29583 information on these fine people. The @file{THANKS} file lists people
29584 who have helped by reporting bugs, taking care of the infrastructure,
29585 providing artwork and themes, making suggestions, and more---thank you!
29588 @c *********************************************************************
29589 @node GNU Free Documentation License
29590 @appendix GNU Free Documentation License
29591 @cindex license, GNU Free Documentation License
29592 @include fdl-1.3.texi
29594 @c *********************************************************************
29595 @node Concept Index
29596 @unnumbered Concept Index
29599 @node Programming Index
29600 @unnumbered Programming Index
29601 @syncodeindex tp fn
29602 @syncodeindex vr fn
29607 @c Local Variables:
29608 @c ispell-local-dictionary: "american";