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, 2021 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, 2021 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, 2020, 2021 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, 2021 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, 2021 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, 2020 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, 2020 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@*
83 Copyright @copyright{} 2020 André Batista@*
84 Copyright @copyright{} 2020 Alexandru-Sergiu Marton@*
85 Copyright @copyright{} 2020 raingloom@*
86 Copyright @copyright{} 2020 Daniel Brooks@*
87 Copyright @copyright{} 2020 John Soo@*
88 Copyright @copyright{} 2020 Jonathan Brielmaier@*
90 Permission is granted to copy, distribute and/or modify this document
91 under the terms of the GNU Free Documentation License, Version 1.3 or
92 any later version published by the Free Software Foundation; with no
93 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
94 copy of the license is included in the section entitled ``GNU Free
95 Documentation License''.
98 @dircategory System administration
100 * Guix: (guix). Manage installed software and system configuration.
101 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
102 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
103 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
104 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
105 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
108 @dircategory Software development
110 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
111 * guix build: (guix)Invoking guix build. Building packages.
112 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
116 @title GNU Guix Reference Manual
117 @subtitle Using the GNU Guix Functional Package Manager
118 @author The GNU Guix Developers
121 @vskip 0pt plus 1filll
122 Edition @value{EDITION} @*
130 @c *********************************************************************
134 This document describes GNU Guix version @value{VERSION}, a functional
135 package management tool written for the GNU system.
137 @c TRANSLATORS: You can replace the following paragraph with information on
138 @c how to join your own translation team and how to report issues with the
140 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
141 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
142 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
143 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
144 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
145 would like to translate it in your native language, consider joining
146 @uref{https://translate.fedoraproject.org/projects/guix/documentation-manual,
150 * Introduction:: What is Guix about?
151 * Installation:: Installing Guix.
152 * System Installation:: Installing the whole operating system.
153 * Getting Started:: Your first steps.
154 * Package Management:: Package installation, upgrade, etc.
155 * Channels:: Customizing the package collection.
156 * Development:: Guix-aided software development.
157 * Programming Interface:: Using Guix in Scheme.
158 * Utilities:: Package management commands.
159 * System Configuration:: Configuring the operating system.
160 * Documentation:: Browsing software user manuals.
161 * Installing Debugging Files:: Feeding the debugger.
162 * Security Updates:: Deploying security fixes quickly.
163 * Bootstrapping:: GNU/Linux built from scratch.
164 * Porting:: Targeting another platform or kernel.
165 * Contributing:: Your help needed!
167 * Acknowledgments:: Thanks!
168 * GNU Free Documentation License:: The license of this manual.
169 * Concept Index:: Concepts.
170 * Programming Index:: Data types, functions, and variables.
173 --- The Detailed Node Listing ---
177 * Managing Software the Guix Way:: What's special.
178 * GNU Distribution:: The packages and tools.
182 * Binary Installation:: Getting Guix running in no time!
183 * Requirements:: Software needed to build and run Guix.
184 * Running the Test Suite:: Testing Guix.
185 * Setting Up the Daemon:: Preparing the build daemon's environment.
186 * Invoking guix-daemon:: Running the build daemon.
187 * Application Setup:: Application-specific setup.
188 * Upgrading Guix:: Upgrading Guix and its build daemon.
190 Setting Up the Daemon
192 * Build Environment Setup:: Preparing the isolated build environment.
193 * Daemon Offload Setup:: Offloading builds to remote machines.
194 * SELinux Support:: Using an SELinux policy for the daemon.
198 * Limitations:: What you can expect.
199 * Hardware Considerations:: Supported hardware.
200 * USB Stick and DVD Installation:: Preparing the installation medium.
201 * Preparing for Installation:: Networking, partitioning, etc.
202 * Guided Graphical Installation:: Easy graphical installation.
203 * Manual Installation:: Manual installation for wizards.
204 * After System Installation:: When installation succeeded.
205 * Installing Guix in a VM:: Guix System playground.
206 * Building the Installation Image:: How this comes to be.
210 * Keyboard Layout and Networking and Partitioning:: Initial setup.
211 * Proceeding with the Installation:: Installing.
215 * Features:: How Guix will make your life brighter.
216 * Invoking guix package:: Package installation, removal, etc.
217 * Substitutes:: Downloading pre-built binaries.
218 * Packages with Multiple Outputs:: Single source package, multiple outputs.
219 * Invoking guix gc:: Running the garbage collector.
220 * Invoking guix pull:: Fetching the latest Guix and distribution.
221 * Invoking guix time-machine:: Running an older revision of Guix.
222 * Inferiors:: Interacting with another revision of Guix.
223 * Invoking guix describe:: Display information about your Guix revision.
224 * Invoking guix archive:: Exporting and importing store files.
228 * Official Substitute Server:: One particular source of substitutes.
229 * Substitute Server Authorization:: How to enable or disable substitutes.
230 * Getting Substitutes from Other Servers:: Substitute diversity.
231 * Substitute Authentication:: How Guix verifies substitutes.
232 * Proxy Settings:: How to get substitutes via proxy.
233 * Substitution Failure:: What happens when substitution fails.
234 * On Trusting Binaries:: How can you trust that binary blob?
238 * Specifying Additional Channels:: Extending the package collection.
239 * Using a Custom Guix Channel:: Using a customized Guix.
240 * Replicating Guix:: Running the @emph{exact same} Guix.
241 * Channel Authentication:: How Guix verifies what it fetches.
242 * Creating a Channel:: How to write your custom channel.
243 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
244 * Declaring Channel Dependencies:: How to depend on other channels.
245 * Specifying Channel Authorizations:: Defining channel authors authorizations.
246 * Primary URL:: Distinguishing mirror to original.
247 * Writing Channel News:: Communicating information to channel's users.
248 * Channels with Substitutes:: Using channels with available substitutes.
252 * Invoking guix environment:: Setting up development environments.
253 * Invoking guix pack:: Creating software bundles.
254 * The GCC toolchain:: Working with languages supported by GCC.
255 * Invoking guix git authenticate:: Authenticating Git repositories.
257 Programming Interface
259 * Package Modules:: Packages from the programmer's viewpoint.
260 * Defining Packages:: Defining new packages.
261 * Defining Package Variants:: Customizing packages.
262 * Build Systems:: Specifying how packages are built.
263 * Build Phases:: Phases of the build process of a package.
264 * Build Utilities:: Helpers for your package definitions and more.
265 * The Store:: Manipulating the package store.
266 * Derivations:: Low-level interface to package derivations.
267 * The Store Monad:: Purely functional interface to the store.
268 * G-Expressions:: Manipulating build expressions.
269 * Invoking guix repl:: Programming Guix in Guile.
273 * package Reference:: The package data type.
274 * origin Reference:: The origin data type.
278 * Invoking guix build:: Building packages from the command line.
279 * Invoking guix edit:: Editing package definitions.
280 * Invoking guix download:: Downloading a file and printing its hash.
281 * Invoking guix hash:: Computing the cryptographic hash of a file.
282 * Invoking guix import:: Importing package definitions.
283 * Invoking guix refresh:: Updating package definitions.
284 * Invoking guix lint:: Finding errors in package definitions.
285 * Invoking guix size:: Profiling disk usage.
286 * Invoking guix graph:: Visualizing the graph of packages.
287 * Invoking guix publish:: Sharing substitutes.
288 * Invoking guix challenge:: Challenging substitute servers.
289 * Invoking guix copy:: Copying to and from a remote store.
290 * Invoking guix container:: Process isolation.
291 * Invoking guix weather:: Assessing substitute availability.
292 * Invoking guix processes:: Listing client processes.
294 Invoking @command{guix build}
296 * Common Build Options:: Build options for most commands.
297 * Package Transformation Options:: Creating variants of packages.
298 * Additional Build Options:: Options specific to 'guix build'.
299 * Debugging Build Failures:: Real life packaging experience.
303 * Using the Configuration System:: Customizing your GNU system.
304 * operating-system Reference:: Detail of operating-system declarations.
305 * File Systems:: Configuring file system mounts.
306 * Mapped Devices:: Block device extra processing.
307 * User Accounts:: Specifying user accounts.
308 * Keyboard Layout:: How the system interprets key strokes.
309 * Locales:: Language and cultural convention settings.
310 * Services:: Specifying system services.
311 * Setuid Programs:: Programs running with root privileges.
312 * X.509 Certificates:: Authenticating HTTPS servers.
313 * Name Service Switch:: Configuring libc's name service switch.
314 * Initial RAM Disk:: Linux-Libre bootstrapping.
315 * Bootloader Configuration:: Configuring the boot loader.
316 * Invoking guix system:: Instantiating a system configuration.
317 * Invoking guix deploy:: Deploying a system configuration to a remote host.
318 * Running Guix in a VM:: How to run Guix System in a virtual machine.
319 * Defining Services:: Adding new service definitions.
323 * Base Services:: Essential system services.
324 * Scheduled Job Execution:: The mcron service.
325 * Log Rotation:: The rottlog service.
326 * Networking Services:: Network setup, SSH daemon, etc.
327 * Unattended Upgrades:: Automated system upgrades.
328 * X Window:: Graphical display.
329 * Printing Services:: Local and remote printer support.
330 * Desktop Services:: D-Bus and desktop services.
331 * Sound Services:: ALSA and Pulseaudio services.
332 * Database Services:: SQL databases, key-value stores, etc.
333 * Mail Services:: IMAP, POP3, SMTP, and all that.
334 * Messaging Services:: Messaging services.
335 * Telephony Services:: Telephony services.
336 * Monitoring Services:: Monitoring services.
337 * Kerberos Services:: Kerberos services.
338 * LDAP Services:: LDAP services.
339 * Web Services:: Web servers.
340 * Certificate Services:: TLS certificates via Let's Encrypt.
341 * DNS Services:: DNS daemons.
342 * VPN Services:: VPN daemons.
343 * Network File System:: NFS related services.
344 * Continuous Integration:: The Cuirass service.
345 * Power Management Services:: Extending battery life.
346 * Audio Services:: The MPD.
347 * Virtualization Services:: Virtualization services.
348 * Version Control Services:: Providing remote access to Git repositories.
349 * Game Services:: Game servers.
350 * PAM Mount Service:: Service to mount volumes when logging in.
351 * Guix Services:: Services relating specifically to Guix.
352 * Linux Services:: Services tied to the Linux kernel.
353 * Hurd Services:: Services specific for a Hurd System.
354 * Miscellaneous Services:: Other services.
358 * Service Composition:: The model for composing services.
359 * Service Types and Services:: Types and services.
360 * Service Reference:: API reference.
361 * Shepherd Services:: A particular type of service.
363 Installing Debugging Files
365 * Separate Debug Info:: Installing 'debug' outputs.
366 * Rebuilding Debug Info:: Building missing debug info.
370 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
371 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
376 @c *********************************************************************
378 @chapter Introduction
381 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
382 using the international phonetic alphabet (IPA).} is a package
383 management tool for and distribution of the GNU system.
384 Guix makes it easy for unprivileged
385 users to install, upgrade, or remove software packages, to roll back to a
386 previous package set, to build packages from source, and generally
387 assists with the creation and maintenance of software environments.
390 @cindex GuixSD, now Guix System
391 @cindex Guix System Distribution, now Guix System
392 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
393 complements the available tools without interference (@pxref{Installation}),
394 or you can use it as a standalone operating system distribution,
395 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
396 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
397 group everything under the ``Guix'' banner since, after all, Guix System is
398 readily available through the @command{guix system} command, even if you're
399 using a different distro underneath!}. @xref{GNU Distribution}.
402 * Managing Software the Guix Way:: What's special.
403 * GNU Distribution:: The packages and tools.
406 @node Managing Software the Guix Way
407 @section Managing Software the Guix Way
409 @cindex user interfaces
410 Guix provides a command-line package management interface
411 (@pxref{Package Management}), tools to help with software development
412 (@pxref{Development}), command-line utilities for more advanced usage
413 (@pxref{Utilities}), as well as Scheme programming interfaces
414 (@pxref{Programming Interface}).
416 Its @dfn{build daemon} is responsible for building packages on behalf of
417 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
418 binaries from authorized sources (@pxref{Substitutes}).
420 @cindex extensibility of the distribution
421 @cindex customization, of packages
422 Guix includes package definitions for many GNU and non-GNU packages, all
423 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
424 user's computing freedom}. It is @emph{extensible}: users can write
425 their own package definitions (@pxref{Defining Packages}) and make them
426 available as independent package modules (@pxref{Package Modules}). It
427 is also @emph{customizable}: users can @emph{derive} specialized package
428 definitions from existing ones, including from the command line
429 (@pxref{Package Transformation Options}).
431 @cindex functional package management
433 Under the hood, Guix implements the @dfn{functional package management}
434 discipline pioneered by Nix (@pxref{Acknowledgments}).
435 In Guix, the package build and installation process is seen
436 as a @emph{function}, in the mathematical sense. That function takes inputs,
437 such as build scripts, a compiler, and libraries, and
438 returns an installed package. As a pure function, its result depends
439 solely on its inputs---for instance, it cannot refer to software or
440 scripts that were not explicitly passed as inputs. A build function
441 always produces the same result when passed a given set of inputs. It
442 cannot alter the environment of the running system in
443 any way; for instance, it cannot create, modify, or delete files outside
444 of its build and installation directories. This is achieved by running
445 build processes in isolated environments (or @dfn{containers}), where only their
446 explicit inputs are visible.
449 The result of package build functions is @dfn{cached} in the file
450 system, in a special directory called @dfn{the store} (@pxref{The
451 Store}). Each package is installed in a directory of its own in the
452 store---by default under @file{/gnu/store}. The directory name contains
453 a hash of all the inputs used to build that package; thus, changing an
454 input yields a different directory name.
456 This approach is the foundation for the salient features of Guix: support
457 for transactional package upgrade and rollback, per-user installation, and
458 garbage collection of packages (@pxref{Features}).
461 @node GNU Distribution
462 @section GNU Distribution
465 Guix comes with a distribution of the GNU system consisting entirely of
466 free software@footnote{The term ``free'' here refers to the
467 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
468 users of that software}.}. The
469 distribution can be installed on its own (@pxref{System Installation}),
470 but it is also possible to install Guix as a package manager on top of
471 an installed GNU/Linux system (@pxref{Installation}). When we need to
472 distinguish between the two, we refer to the standalone distribution as
475 The distribution provides core GNU packages such as GNU libc, GCC, and
476 Binutils, as well as many GNU and non-GNU applications. The complete
477 list of available packages can be browsed
478 @url{https://www.gnu.org/software/guix/packages,on-line} or by
479 running @command{guix package} (@pxref{Invoking guix package}):
482 guix package --list-available
485 Our goal is to provide a practical 100% free software distribution of
486 Linux-based and other variants of GNU, with a focus on the promotion and
487 tight integration of GNU components, and an emphasis on programs and
488 tools that help users exert that freedom.
490 Packages are currently available on the following platforms:
495 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel.
498 Intel 32-bit architecture (IA32), Linux-Libre kernel.
501 ARMv7-A architecture with hard float, Thumb-2 and NEON,
502 using the EABI hard-float application binary interface (ABI),
503 and Linux-Libre kernel.
506 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
509 @uref{https://hurd.gnu.org, GNU/Hurd} on the Intel 32-bit architecture
512 This configuration is experimental and under development. The easiest
513 way for you to give it a try is by setting up an instance of
514 @code{hurd-vm-service-type} on your GNU/Linux machine
515 (@pxref{transparent-emulation-qemu, @code{hurd-vm-service-type}}).
516 @xref{Contributing}, on how to help!
518 @item mips64el-linux (deprecated)
519 little-endian 64-bit MIPS processors, specifically the Loongson series,
520 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
521 supported; in particular, there is no ongoing work to ensure that this
522 architecture still works. Should someone decide they wish to revive this
523 architecture then the code is still available.
527 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
528 configuration and Guix takes care of instantiating the configuration in a
529 transactional, reproducible, and stateless fashion (@pxref{System
530 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
531 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
532 Manual}), the well-known GNU utilities and tool chain, as well as the
533 graphical environment or system services of your choice.
535 Guix System is available on all the above platforms except
536 @code{mips64el-linux}.
539 For information on porting to other architectures or kernels,
542 Building this distribution is a cooperative effort, and you are invited
543 to join! @xref{Contributing}, for information about how you can help.
546 @c *********************************************************************
548 @chapter Installation
550 @cindex installing Guix
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} to install Guix on top of a running GNU/Linux system,
556 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
557 with the installation of the package manager, which can be done on top of a
558 running GNU/Linux system. If, instead, you want to install the complete GNU
559 operating system, @pxref{System Installation}.} The script automates the
560 download, installation, and initial configuration of Guix. It should be run
564 @cindex foreign distro
565 @cindex directories related to foreign distro
566 When installed on a foreign distro, GNU@tie{}Guix complements the available
567 tools without interference. Its data lives exclusively in two directories,
568 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
569 such as @file{/etc}, are left untouched.
571 Once installed, Guix can be updated by running @command{guix pull}
572 (@pxref{Invoking guix pull}).
574 If you prefer to perform the installation steps manually or want to tweak
575 them, you may find the following subsections useful. They describe the
576 software requirements of Guix, as well as how to install it manually and get
580 * Binary Installation:: Getting Guix running in no time!
581 * Requirements:: Software needed to build and run Guix.
582 * Running the Test Suite:: Testing Guix.
583 * Setting Up the Daemon:: Preparing the build daemon's environment.
584 * Invoking guix-daemon:: Running the build daemon.
585 * Application Setup:: Application-specific setup.
586 * Upgrading Guix:: Upgrading Guix and its build daemon.
589 @node Binary Installation
590 @section Binary Installation
592 @cindex installing Guix from binaries
593 @cindex installer script
594 This section describes how to install Guix on an arbitrary system from a
595 self-contained tarball providing binaries for Guix and for all its
596 dependencies. This is often quicker than installing from source, which
597 is described in the next sections. The only requirement is to have
600 @c Note duplicated from the ``Installation'' node.
602 We recommend the use of this
603 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
604 shell installer script}. The script automates the download, installation, and
605 initial configuration steps described below. It should be run as the root
606 user. As root, you can thus run this:
610 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
611 chmod +x guix-install.sh
615 When you're done, @pxref{Application Setup} for extra configuration you
616 might need, and @ref{Getting Started} for your first steps!
619 Installing goes along these lines:
623 @cindex downloading Guix binary
624 Download the binary tarball from
625 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
626 where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
627 @code{i686} (32-bits) machine already running the kernel Linux, and so on
628 (@pxref{GNU Distribution}).
630 @c The following is somewhat duplicated in ``System Installation''.
631 Make sure to download the associated @file{.sig} file and to verify the
632 authenticity of the tarball against it, along these lines:
635 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
636 $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
639 If that command fails because you do not have the required public key,
640 then run this command to import it:
643 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
644 -qO - | gpg --import -
648 and rerun the @code{gpg --verify} command.
650 Take note that a warning like ``This key is not certified with a trusted
651 signature!'' is normal.
653 @c end authentication part
656 Now, you need to become the @code{root} user. Depending on your distribution,
657 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
661 # tar --warning=no-timestamp -xf \
662 /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
663 # mv var/guix /var/ && mv gnu /
666 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
667 The latter contains a ready-to-use profile for @code{root} (see next
670 Do @emph{not} unpack the tarball on a working Guix system since that
671 would overwrite its own essential files.
673 The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
674 not emit warnings about ``implausibly old time stamps'' (such
675 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
677 They stem from the fact that all the
678 files in the archive have their modification time set to 1 (which
679 means January 1st, 1970). This is done on purpose to make sure the
680 archive content is independent of its creation time, thus making it
684 Make the profile available under @file{~root/.config/guix/current}, which is
685 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
688 # mkdir -p ~root/.config/guix
689 # ln -sf /var/guix/profiles/per-user/root/current-guix \
690 ~root/.config/guix/current
693 Source @file{etc/profile} to augment @env{PATH} and other relevant
694 environment variables:
697 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
698 source $GUIX_PROFILE/etc/profile
702 Create the group and user accounts for build users as explained below
703 (@pxref{Build Environment Setup}).
706 Run the daemon, and set it to automatically start on boot.
708 If your host distro uses the systemd init system, this can be achieved
711 @c Versions of systemd that supported symlinked service files are not
712 @c yet widely deployed, so we should suggest that users copy the service
715 @c See this thread for more information:
716 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
719 # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
720 ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
722 # systemctl enable --now gnu-store.mount guix-daemon
725 If your host distro uses the Upstart init system:
728 # initctl reload-configuration
729 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
734 Otherwise, you can still start the daemon manually with:
737 # ~root/.config/guix/current/bin/guix-daemon \
738 --build-users-group=guixbuild
742 Make the @command{guix} command available to other users on the machine,
746 # mkdir -p /usr/local/bin
748 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
751 It is also a good idea to make the Info version of this manual available
755 # mkdir -p /usr/local/share/info
756 # cd /usr/local/share/info
757 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
761 That way, assuming @file{/usr/local/share/info} is in the search path,
762 running @command{info guix} will open this manual (@pxref{Other Info
763 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
767 @cindex substitutes, authorization thereof
768 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
769 (@pxref{Substitutes}), authorize them:
772 # guix archive --authorize < \
773 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
777 Each user may need to perform a few additional steps to make their Guix
778 environment ready for use, @pxref{Application Setup}.
781 Voilà, the installation is complete!
783 You can confirm that Guix is working by installing a sample package into
790 The binary installation tarball can be (re)produced and verified simply
791 by running the following command in the Guix source tree:
794 make guix-binary.@var{system}.tar.xz
798 ...@: which, in turn, runs:
801 guix pack -s @var{system} --localstatedir \
802 --profile-name=current-guix guix
805 @xref{Invoking guix pack}, for more info on this handy tool.
808 @section Requirements
810 This section lists requirements when building Guix from source. The
811 build procedure for Guix is the same as for other GNU software, and is
812 not covered here. Please see the files @file{README} and @file{INSTALL}
813 in the Guix source tree for additional details.
815 @cindex official website
816 GNU Guix is available for download from its website at
817 @url{https://www.gnu.org/software/guix/}.
819 GNU Guix depends on the following packages:
822 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x or
824 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
827 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
828 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
829 Guile,, gnutls-guile, GnuTLS-Guile});
831 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
833 @item @uref{https://notabug.org/guile-zlib/guile-zlib, Guile-zlib};
834 @item @uref{https://notabug.org/guile-lzlib/guile-lzlib, Guile-lzlib};
835 @item @uref{https://www.nongnu.org/guile-avahi/, Guile-Avahi};
837 @c FIXME: Specify a version number once a release has been made.
838 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, version 0.3.0
840 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON}
842 @item @url{https://www.gnu.org/software/make/, GNU Make}.
845 The following dependencies are optional:
849 @c Note: We need at least 0.13.0 for #:nodelay.
850 Support for build offloading (@pxref{Daemon Offload Setup}) and
851 @command{guix copy} (@pxref{Invoking guix copy}) depends on
852 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
853 version 0.13.0 or later.
856 @uref{https://notabug.org/guile-zstd/guile-zstd, Guile-zstd}, for zstd
857 compression and decompression in @command{guix publish} and for
858 substitutes (@pxref{Invoking guix publish}).
861 @uref{https://ngyro.com/software/guile-semver.html, Guile-Semver} for
862 the @code{crate} importer (@pxref{Invoking guix import}).
865 When @url{http://www.bzip.org, libbz2} is available,
866 @command{guix-daemon} can use it to compress build logs.
869 Unless @option{--disable-daemon} was passed to @command{configure}, the
870 following packages are also needed:
873 @item @url{https://gnupg.org/, GNU libgcrypt};
874 @item @url{https://sqlite.org, SQLite 3};
875 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
879 @cindex state directory
880 When configuring Guix on a system that already has a Guix installation,
881 be sure to specify the same state directory as the existing installation
882 using the @option{--localstatedir} option of the @command{configure}
883 script (@pxref{Directory Variables, @code{localstatedir},, standards,
884 GNU Coding Standards}). Usually, this @var{localstatedir} option is
885 set to the value @file{/var}. The @command{configure} script protects
886 against unintended misconfiguration of @var{localstatedir} so you do not
887 inadvertently corrupt your store (@pxref{The Store}).
889 @node Running the Test Suite
890 @section Running the Test Suite
893 After a successful @command{configure} and @code{make} run, it is a good
894 idea to run the test suite. It can help catch issues with the setup or
895 environment, or bugs in Guix itself---and really, reporting test
896 failures is a good way to help improve the software. To run the test
903 Test cases can run in parallel: you can use the @code{-j} option of
904 GNU@tie{}make to speed things up. The first run may take a few minutes
905 on a recent machine; subsequent runs will be faster because the store
906 that is created for test purposes will already have various things in
909 It is also possible to run a subset of the tests by defining the
910 @code{TESTS} makefile variable as in this example:
913 make check TESTS="tests/store.scm tests/cpio.scm"
916 By default, tests results are displayed at a file level. In order to
917 see the details of every individual test cases, it is possible to define
918 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
921 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
924 The underlying SRFI 64 custom Automake test driver used for the 'check'
925 test suite (located at @file{build-aux/test-driver.scm}) also allows
926 selecting which test cases to run at a finer level, via its
927 @option{--select} and @option{--exclude} options. Here's an example, to
928 run all the test cases from the @file{tests/packages.scm} test file
929 whose names start with ``transaction-upgrade-entry'':
932 export SCM_LOG_DRIVER_FLAGS="--select=^transaction-upgrade-entry"
933 make check TESTS="tests/packages.scm"
936 Those wishing to inspect the results of failed tests directly from the
937 command line can add the @option{--errors-only=yes} option to the
938 @code{SCM_LOG_DRIVER_FLAGS} makefile variable and set the @code{VERBOSE}
939 Automake makefile variable, as in:
942 make check SCM_LOG_DRIVER_FLAGS="--brief=no --errors-only=yes" VERBOSE=1
945 The @option{--show-duration=yes} option can be used to print the
946 duration of the individual test cases, when used in combination with
950 make check SCM_LOG_DRIVER_FLAGS="--brief=no --show-duration=yes"
953 @xref{Parallel Test Harness,,,automake,GNU Automake} for more
954 information about the Automake Parallel Test Harness.
956 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
957 @file{test-suite.log} file. Please specify the Guix version being used
958 as well as version numbers of the dependencies (@pxref{Requirements}) in
961 Guix also comes with a whole-system test suite that tests complete
962 Guix System instances. It can only run on systems where
963 Guix is already installed, using:
970 or, again, by defining @code{TESTS} to select a subset of tests to run:
973 make check-system TESTS="basic mcron"
976 These system tests are defined in the @code{(gnu tests @dots{})}
977 modules. They work by running the operating systems under test with
978 lightweight instrumentation in a virtual machine (VM). They can be
979 computationally intensive or rather cheap, depending on whether
980 substitutes are available for their dependencies (@pxref{Substitutes}).
981 Some of them require a lot of storage space to hold VM images.
983 Again in case of test failures, please send @email{bug-guix@@gnu.org}
986 @node Setting Up the Daemon
987 @section Setting Up the Daemon
990 Operations such as building a package or running the garbage collector
991 are all performed by a specialized process, the @dfn{build daemon}, on
992 behalf of clients. Only the daemon may access the store and its
993 associated database. Thus, any operation that manipulates the store
994 goes through the daemon. For instance, command-line tools such as
995 @command{guix package} and @command{guix build} communicate with the
996 daemon (@i{via} remote procedure calls) to instruct it what to do.
998 The following sections explain how to prepare the build daemon's
999 environment. See also @ref{Substitutes}, for information on how to allow
1000 the daemon to download pre-built binaries.
1003 * Build Environment Setup:: Preparing the isolated build environment.
1004 * Daemon Offload Setup:: Offloading builds to remote machines.
1005 * SELinux Support:: Using an SELinux policy for the daemon.
1008 @node Build Environment Setup
1009 @subsection Build Environment Setup
1011 @cindex build environment
1012 In a standard multi-user setup, Guix and its daemon---the
1013 @command{guix-daemon} program---are installed by the system
1014 administrator; @file{/gnu/store} is owned by @code{root} and
1015 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
1016 Guix tools to build packages or otherwise access the store, and the
1017 daemon will do it on their behalf, ensuring that the store is kept in a
1018 consistent state, and allowing built packages to be shared among users.
1021 When @command{guix-daemon} runs as @code{root}, you may not want package
1022 build processes themselves to run as @code{root} too, for obvious
1023 security reasons. To avoid that, a special pool of @dfn{build users}
1024 should be created for use by build processes started by the daemon.
1025 These build users need not have a shell and a home directory: they will
1026 just be used when the daemon drops @code{root} privileges in build
1027 processes. Having several such users allows the daemon to launch
1028 distinct build processes under separate UIDs, which guarantees that they
1029 do not interfere with each other---an essential feature since builds are
1030 regarded as pure functions (@pxref{Introduction}).
1032 On a GNU/Linux system, a build user pool may be created like this (using
1033 Bash syntax and the @code{shadow} commands):
1035 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
1036 @c for why `-G' is needed.
1038 # groupadd --system guixbuild
1039 # for i in `seq -w 1 10`;
1041 useradd -g guixbuild -G guixbuild \
1042 -d /var/empty -s `which nologin` \
1043 -c "Guix build user $i" --system \
1049 The number of build users determines how many build jobs may run in
1050 parallel, as specified by the @option{--max-jobs} option
1051 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
1052 @command{guix system vm} and related commands, you may need to add the
1053 build users to the @code{kvm} group so they can access @file{/dev/kvm},
1054 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
1055 (@pxref{Invoking guix system}).
1057 The @code{guix-daemon} program may then be run as @code{root} with the
1058 following command@footnote{If your machine uses the systemd init system,
1059 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
1060 file in @file{/etc/systemd/system} will ensure that
1061 @command{guix-daemon} is automatically started. Similarly, if your
1062 machine uses the Upstart init system, drop the
1063 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
1064 file in @file{/etc/init}.}:
1067 # guix-daemon --build-users-group=guixbuild
1072 This way, the daemon starts build processes in a chroot, under one of
1073 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
1074 environment contains nothing but:
1076 @c Keep this list in sync with libstore/build.cc! -----------------------
1079 a minimal @code{/dev} directory, created mostly independently from the
1080 host @code{/dev}@footnote{``Mostly'', because while the set of files
1081 that appear in the chroot's @code{/dev} is fixed, most of these files
1082 can only be created if the host has them.};
1085 the @code{/proc} directory; it only shows the processes of the container
1086 since a separate PID name space is used;
1089 @file{/etc/passwd} with an entry for the current user and an entry for
1093 @file{/etc/group} with an entry for the user's group;
1096 @file{/etc/hosts} with an entry that maps @code{localhost} to
1100 a writable @file{/tmp} directory.
1103 You can influence the directory where the daemon stores build trees
1104 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1105 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1106 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1107 This way, the value of @env{TMPDIR} does not leak inside build
1108 environments, which avoids discrepancies in cases where build processes
1109 capture the name of their build tree.
1113 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1114 environment variables for HTTP and HTTPS downloads it performs, be it
1115 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1116 (@pxref{Substitutes}).
1118 If you are installing Guix as an unprivileged user, it is still possible
1119 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1120 However, build processes will not be isolated from one another, and not
1121 from the rest of the system. Thus, build processes may interfere with
1122 each other, and may access programs, libraries, and other files
1123 available on the system---making it much harder to view them as
1124 @emph{pure} functions.
1127 @node Daemon Offload Setup
1128 @subsection Using the Offload Facility
1132 When desired, the build daemon can @dfn{offload} derivation builds to
1133 other machines running Guix, using the @code{offload} @dfn{build
1134 hook}@footnote{This feature is available only when
1135 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1136 present.}. When that feature is enabled, a list of user-specified build
1137 machines is read from @file{/etc/guix/machines.scm}; every time a build
1138 is requested, for instance via @code{guix build}, the daemon attempts to
1139 offload it to one of the machines that satisfy the constraints of the
1140 derivation, in particular its system types---e.g., @code{x86_64-linux}.
1141 A single machine can have multiple system types, either because its
1142 architecture natively supports it, via emulation
1143 (@pxref{transparent-emulation-qemu, Transparent Emulation with QEMU}),
1144 or both. Missing prerequisites for the build are
1145 copied over SSH to the target machine, which then proceeds with the
1146 build; upon success the output(s) of the build are copied back to the
1147 initial machine. The offload facility comes with a basic scheduler that
1148 attempts to select the best machine. The best machine is chosen among
1149 the available machines based on criteria such as:
1153 The availability of a build slot. A build machine can have as many
1154 build slots (connections) as the value of the @code{parallel-builds}
1155 field of its @code{build-machine} object.
1158 Its relative speed, as defined via the @code{speed} field of its
1159 @code{build-machine} object.
1162 Its load. The normalized machine load must be lower than a threshold
1163 value, configurable via the @code{overload-threshold} field of its
1164 @code{build-machine} object.
1167 Disk space availability. More than a 100 MiB must be available.
1170 The @file{/etc/guix/machines.scm} file typically looks like this:
1173 (list (build-machine
1174 (name "eightysix.example.org")
1175 (systems (list "x86_64-linux" "i686-linux"))
1176 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1178 (speed 2.)) ;incredibly fast!
1181 (name "armeight.example.org")
1182 (systems (list "aarch64-linux"))
1183 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1186 (string-append (getenv "HOME")
1187 "/.ssh/identity-for-guix"))))
1191 In the example above we specify a list of two build machines, one for
1192 the @code{x86_64} and @code{i686} architectures and one for the
1193 @code{aarch64} architecture.
1195 In fact, this file is---not surprisingly!---a Scheme file that is
1196 evaluated when the @code{offload} hook is started. Its return value
1197 must be a list of @code{build-machine} objects. While this example
1198 shows a fixed list of build machines, one could imagine, say, using
1199 DNS-SD to return a list of potential build machines discovered in the
1200 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1201 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1204 @deftp {Data Type} build-machine
1205 This data type represents build machines to which the daemon may offload
1206 builds. The important fields are:
1211 The host name of the remote machine.
1214 The system types the remote machine supports---e.g., @code{(list
1215 "x86_64-linux" "i686-linux")}.
1218 The user account to use when connecting to the remote machine over SSH.
1219 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1220 allow non-interactive logins.
1223 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1224 This is used to authenticate the machine when we connect to it. It is a
1225 long string that looks like this:
1228 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1231 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1232 key can be found in a file such as
1233 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1235 If the machine is running the SSH daemon of GNU@tie{}lsh,
1236 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1237 similar file. It can be converted to the OpenSSH format using
1238 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1241 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1242 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1247 A number of optional fields may be specified:
1251 @item @code{port} (default: @code{22})
1252 Port number of SSH server on the machine.
1254 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1255 The SSH private key file to use when connecting to the machine, in
1256 OpenSSH format. This key must not be protected with a passphrase.
1258 Note that the default value is the private key @emph{of the root
1259 account}. Make sure it exists if you use the default.
1261 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1262 @itemx @code{compression-level} (default: @code{3})
1263 The SSH-level compression methods and compression level requested.
1265 Note that offloading relies on SSH compression to reduce bandwidth usage
1266 when transferring files to and from build machines.
1268 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1269 File name of the Unix-domain socket @command{guix-daemon} is listening
1272 @item @code{overload-threshold} (default: @code{0.6})
1273 The load threshold above which a potential offload machine is
1274 disregarded by the offload scheduler. The value roughly translates to
1275 the total processor usage of the build machine, ranging from 0.0 (0%) to
1276 1.0 (100%). It can also be disabled by setting
1277 @code{overload-threshold} to @code{#f}.
1279 @item @code{parallel-builds} (default: @code{1})
1280 The number of builds that may run in parallel on the machine.
1282 @item @code{speed} (default: @code{1.0})
1283 A ``relative speed factor''. The offload scheduler will tend to prefer
1284 machines with a higher speed factor.
1286 @item @code{features} (default: @code{'()})
1287 A list of strings denoting specific features supported by the machine.
1288 An example is @code{"kvm"} for machines that have the KVM Linux modules
1289 and corresponding hardware support. Derivations can request features by
1290 name, and they will be scheduled on matching build machines.
1295 The @command{guix} command must be in the search path on the build
1296 machines. You can check whether this is the case by running:
1299 ssh build-machine guix repl --version
1302 There is one last thing to do once @file{machines.scm} is in place. As
1303 explained above, when offloading, files are transferred back and forth
1304 between the machine stores. For this to work, you first need to
1305 generate a key pair on each machine to allow the daemon to export signed
1306 archives of files from the store (@pxref{Invoking guix archive}):
1309 # guix archive --generate-key
1313 Each build machine must authorize the key of the master machine so that
1314 it accepts store items it receives from the master:
1317 # guix archive --authorize < master-public-key.txt
1321 Likewise, the master machine must authorize the key of each build machine.
1323 All the fuss with keys is here to express pairwise mutual trust
1324 relations between the master and the build machines. Concretely, when
1325 the master receives files from a build machine (and @i{vice versa}), its
1326 build daemon can make sure they are genuine, have not been tampered
1327 with, and that they are signed by an authorized key.
1329 @cindex offload test
1330 To test whether your setup is operational, run this command on the
1337 This will attempt to connect to each of the build machines specified in
1338 @file{/etc/guix/machines.scm}, make sure Guix is
1339 available on each machine, attempt to export to the machine and import
1340 from it, and report any error in the process.
1342 If you want to test a different machine file, just specify it on the
1346 # guix offload test machines-qualif.scm
1349 Last, you can test the subset of the machines whose name matches a
1350 regular expression like this:
1353 # guix offload test machines.scm '\.gnu\.org$'
1356 @cindex offload status
1357 To display the current load of all build hosts, run this command on the
1361 # guix offload status
1365 @node SELinux Support
1366 @subsection SELinux Support
1368 @cindex SELinux, daemon policy
1369 @cindex mandatory access control, SELinux
1370 @cindex security, guix-daemon
1371 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1372 can be installed on a system where SELinux is enabled, in order to label
1373 Guix files and to specify the expected behavior of the daemon. Since
1374 Guix System does not provide an SELinux base policy, the daemon policy cannot
1375 be used on Guix System.
1377 @subsubsection Installing the SELinux policy
1378 @cindex SELinux, policy installation
1379 To install the policy run this command as root:
1382 semodule -i etc/guix-daemon.cil
1385 Then relabel the file system with @code{restorecon} or by a different
1386 mechanism provided by your system.
1388 Once the policy is installed, the file system has been relabeled, and
1389 the daemon has been restarted, it should be running in the
1390 @code{guix_daemon_t} context. You can confirm this with the following
1394 ps -Zax | grep guix-daemon
1397 Monitor the SELinux log files as you run a command like @code{guix build
1398 hello} to convince yourself that SELinux permits all necessary
1401 @subsubsection Limitations
1402 @cindex SELinux, limitations
1404 This policy is not perfect. Here is a list of limitations or quirks
1405 that should be considered when deploying the provided SELinux policy for
1410 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1411 operations involve contexts that have anything to do with
1412 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1413 but it would be preferrable to define socket rules for only this label.
1416 @code{guix gc} cannot access arbitrary links to profiles. By design,
1417 the file label of the destination of a symlink is independent of the
1418 file label of the link itself. Although all profiles under
1419 $localstatedir are labelled, the links to these profiles inherit the
1420 label of the directory they are in. For links in the user’s home
1421 directory this will be @code{user_home_t}. But for links from the root
1422 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1423 directory, etc, this won’t work. @code{guix gc} would be prevented from
1424 reading and following these links.
1427 The daemon’s feature to listen for TCP connections might no longer work.
1428 This might require extra rules, because SELinux treats network sockets
1429 differently from files.
1432 Currently all files with a name matching the regular expression
1433 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1434 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1435 that name in any profile would be permitted to run in the
1436 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1437 build a package that provides this executable and convince a user to
1438 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1439 At that point SELinux could not prevent it from accessing files that are
1440 allowed for processes in that domain.
1442 You will need to relabel the store directory after all upgrades to
1443 @file{guix-daemon}, such as after running @code{guix pull}. Assuming the
1444 store is in @file{/gnu}, you can do this with @code{restorecon -vR /gnu},
1445 or by other means provided by your operating system.
1447 We could generate a much more restrictive policy at installation time,
1448 so that only the @emph{exact} file name of the currently installed
1449 @code{guix-daemon} executable would be labelled with
1450 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1451 The downside is that root would have to install or upgrade the policy at
1452 installation time whenever the Guix package that provides the
1453 effectively running @code{guix-daemon} executable is upgraded.
1456 @node Invoking guix-daemon
1457 @section Invoking @command{guix-daemon}
1459 The @command{guix-daemon} program implements all the functionality to
1460 access the store. This includes launching build processes, running the
1461 garbage collector, querying the availability of a build result, etc. It
1462 is normally run as @code{root} like this:
1465 # guix-daemon --build-users-group=guixbuild
1469 For details on how to set it up, @pxref{Setting Up the Daemon}.
1472 @cindex container, build environment
1473 @cindex build environment
1474 @cindex reproducible builds
1475 By default, @command{guix-daemon} launches build processes under
1476 different UIDs, taken from the build group specified with
1477 @option{--build-users-group}. In addition, each build process is run in a
1478 chroot environment that only contains the subset of the store that the
1479 build process depends on, as specified by its derivation
1480 (@pxref{Programming Interface, derivation}), plus a set of specific
1481 system directories. By default, the latter contains @file{/dev} and
1482 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1483 @dfn{container}: in addition to having its own file system tree, it has
1484 a separate mount name space, its own PID name space, network name space,
1485 etc. This helps achieve reproducible builds (@pxref{Features}).
1487 When the daemon performs a build on behalf of the user, it creates a
1488 build directory under @file{/tmp} or under the directory specified by
1489 its @env{TMPDIR} environment variable. This directory is shared with
1490 the container for the duration of the build, though within the container,
1491 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1493 The build directory is automatically deleted upon completion, unless the
1494 build failed and the client specified @option{--keep-failed}
1495 (@pxref{Invoking guix build, @option{--keep-failed}}).
1497 The daemon listens for connections and spawns one sub-process for each session
1498 started by a client (one of the @command{guix} sub-commands). The
1499 @command{guix processes} command allows you to get an overview of the activity
1500 on your system by viewing each of the active sessions and clients.
1501 @xref{Invoking guix processes}, for more information.
1503 The following command-line options are supported:
1506 @item --build-users-group=@var{group}
1507 Take users from @var{group} to run build processes (@pxref{Setting Up
1508 the Daemon, build users}).
1510 @item --no-substitutes
1512 Do not use substitutes for build products. That is, always build things
1513 locally instead of allowing downloads of pre-built binaries
1514 (@pxref{Substitutes}).
1516 When the daemon runs with @option{--no-substitutes}, clients can still
1517 explicitly enable substitution @i{via} the @code{set-build-options}
1518 remote procedure call (@pxref{The Store}).
1520 @anchor{daemon-substitute-urls}
1521 @item --substitute-urls=@var{urls}
1522 Consider @var{urls} the default whitespace-separated list of substitute
1523 source URLs. When this option is omitted,
1524 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1526 This means that substitutes may be downloaded from @var{urls}, as long
1527 as they are signed by a trusted signature (@pxref{Substitutes}).
1529 @xref{Getting Substitutes from Other Servers}, for more information on
1530 how to configure the daemon to get substitutes from other servers.
1534 Do not use offload builds to other machines (@pxref{Daemon Offload
1535 Setup}). That is, always build things locally instead of offloading
1536 builds to remote machines.
1538 @item --cache-failures
1539 Cache build failures. By default, only successful builds are cached.
1541 When this option is used, @command{guix gc --list-failures} can be used
1542 to query the set of store items marked as failed; @command{guix gc
1543 --clear-failures} removes store items from the set of cached failures.
1544 @xref{Invoking guix gc}.
1546 @item --cores=@var{n}
1548 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1551 The default value is @code{0}, but it may be overridden by clients, such
1552 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1555 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1556 in the build process, which can then use it to exploit internal
1557 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1559 @item --max-jobs=@var{n}
1561 Allow at most @var{n} build jobs in parallel. The default value is
1562 @code{1}. Setting it to @code{0} means that no builds will be performed
1563 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1564 Setup}), or simply fail.
1566 @item --max-silent-time=@var{seconds}
1567 When the build or substitution process remains silent for more than
1568 @var{seconds}, terminate it and report a build failure.
1570 The default value is @code{0}, which disables the timeout.
1572 The value specified here can be overridden by clients (@pxref{Common
1573 Build Options, @option{--max-silent-time}}).
1575 @item --timeout=@var{seconds}
1576 Likewise, when the build or substitution process lasts for more than
1577 @var{seconds}, terminate it and report a build failure.
1579 The default value is @code{0}, which disables the timeout.
1581 The value specified here can be overridden by clients (@pxref{Common
1582 Build Options, @option{--timeout}}).
1584 @item --rounds=@var{N}
1585 Build each derivation @var{n} times in a row, and raise an error if
1586 consecutive build results are not bit-for-bit identical. Note that this
1587 setting can be overridden by clients such as @command{guix build}
1588 (@pxref{Invoking guix build}).
1590 When used in conjunction with @option{--keep-failed}, the differing
1591 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1592 This makes it easy to look for differences between the two results.
1595 Produce debugging output.
1597 This is useful to debug daemon start-up issues, but then it may be
1598 overridden by clients, for example the @option{--verbosity} option of
1599 @command{guix build} (@pxref{Invoking guix build}).
1601 @item --chroot-directory=@var{dir}
1602 Add @var{dir} to the build chroot.
1604 Doing this may change the result of build processes---for instance if
1605 they use optional dependencies found in @var{dir} when it is available,
1606 and not otherwise. For that reason, it is not recommended to do so.
1607 Instead, make sure that each derivation declares all the inputs that it
1610 @item --disable-chroot
1611 Disable chroot builds.
1613 Using this option is not recommended since, again, it would allow build
1614 processes to gain access to undeclared dependencies. It is necessary,
1615 though, when @command{guix-daemon} is running under an unprivileged user
1618 @item --log-compression=@var{type}
1619 Compress build logs according to @var{type}, one of @code{gzip},
1620 @code{bzip2}, or @code{none}.
1622 Unless @option{--lose-logs} is used, all the build logs are kept in the
1623 @var{localstatedir}. To save space, the daemon automatically compresses
1624 them with Bzip2 by default.
1626 @item --discover[=yes|no]
1627 Whether to discover substitute servers on the local network using mDNS
1630 This feature is still experimental. However, here are a few
1635 It might be faster/less expensive than fetching from remote servers;
1637 There are no security risks, only genuine substitutes will be used
1638 (@pxref{Substitute Authentication});
1640 An attacker advertising @command{guix publish} on your LAN cannot serve
1641 you malicious binaries, but they can learn what software you’re
1644 Servers may serve substitute over HTTP, unencrypted, so anyone on the
1645 LAN can see what software you’re installing.
1648 It is also possible to enable or disable substitute server discovery at
1649 run-time by running:
1652 herd discover guix-daemon on
1653 herd discover guix-daemon off
1656 @item --disable-deduplication
1657 @cindex deduplication
1658 Disable automatic file ``deduplication'' in the store.
1660 By default, files added to the store are automatically ``deduplicated'':
1661 if a newly added file is identical to another one found in the store,
1662 the daemon makes the new file a hard link to the other file. This can
1663 noticeably reduce disk usage, at the expense of slightly increased
1664 input/output load at the end of a build process. This option disables
1667 @item --gc-keep-outputs[=yes|no]
1668 Tell whether the garbage collector (GC) must keep outputs of live
1672 @cindex garbage collector roots
1673 When set to @code{yes}, the GC will keep the outputs of any live
1674 derivation available in the store---the @file{.drv} files. The default
1675 is @code{no}, meaning that derivation outputs are kept only if they are
1676 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1679 @item --gc-keep-derivations[=yes|no]
1680 Tell whether the garbage collector (GC) must keep derivations
1681 corresponding to live outputs.
1683 When set to @code{yes}, as is the case by default, the GC keeps
1684 derivations---i.e., @file{.drv} files---as long as at least one of their
1685 outputs is live. This allows users to keep track of the origins of
1686 items in their store. Setting it to @code{no} saves a bit of disk
1689 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1690 liveness to flow from outputs to derivations, and setting
1691 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1692 derivations to outputs. When both are set to @code{yes}, the effect is
1693 to keep all the build prerequisites (the sources, compiler, libraries,
1694 and other build-time tools) of live objects in the store, regardless of
1695 whether these prerequisites are reachable from a GC root. This is
1696 convenient for developers since it saves rebuilds or downloads.
1698 @item --impersonate-linux-2.6
1699 On Linux-based systems, impersonate Linux 2.6. This means that the
1700 kernel's @command{uname} system call will report 2.6 as the release number.
1702 This might be helpful to build programs that (usually wrongfully) depend
1703 on the kernel version number.
1706 Do not keep build logs. By default they are kept under
1707 @file{@var{localstatedir}/guix/log}.
1709 @item --system=@var{system}
1710 Assume @var{system} as the current system type. By default it is the
1711 architecture/kernel pair found at configure time, such as
1712 @code{x86_64-linux}.
1714 @item --listen=@var{endpoint}
1715 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1716 as the file name of a Unix-domain socket if it starts with
1717 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1718 host name or host name and port to listen to. Here are a few examples:
1721 @item --listen=/gnu/var/daemon
1722 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1723 creating it if needed.
1725 @item --listen=localhost
1726 @cindex daemon, remote access
1727 @cindex remote access to the daemon
1728 @cindex daemon, cluster setup
1729 @cindex clusters, daemon setup
1730 Listen for TCP connections on the network interface corresponding to
1731 @code{localhost}, on port 44146.
1733 @item --listen=128.0.0.42:1234
1734 Listen for TCP connections on the network interface corresponding to
1735 @code{128.0.0.42}, on port 1234.
1738 This option can be repeated multiple times, in which case
1739 @command{guix-daemon} accepts connections on all the specified
1740 endpoints. Users can tell client commands what endpoint to connect to
1741 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1742 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1745 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1746 @option{--listen=@var{host}} is suitable on local networks, such as
1747 clusters, where only trusted nodes may connect to the build daemon. In
1748 other cases where remote access to the daemon is needed, we recommend
1749 using Unix-domain sockets along with SSH.
1752 When @option{--listen} is omitted, @command{guix-daemon} listens for
1753 connections on the Unix-domain socket located at
1754 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1758 @node Application Setup
1759 @section Application Setup
1761 @cindex foreign distro
1762 When using Guix on top of GNU/Linux distribution other than Guix System---a
1763 so-called @dfn{foreign distro}---a few additional steps are needed to
1764 get everything in place. Here are some of them.
1768 @anchor{locales-and-locpath}
1769 @cindex locales, when not on Guix System
1771 @vindex GUIX_LOCPATH
1772 Packages installed @i{via} Guix will not use the locale data of the
1773 host system. Instead, you must first install one of the locale packages
1774 available with Guix and then define the @env{GUIX_LOCPATH} environment
1778 $ guix install glibc-locales
1779 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1782 Note that the @code{glibc-locales} package contains data for all the
1783 locales supported by the GNU@tie{}libc and weighs in at around
1784 917@tie{}MiB@. Alternatively, the @code{glibc-utf8-locales} is smaller but
1785 limited to a few UTF-8 locales.
1787 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1788 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1789 Manual}). There are two important differences though:
1793 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1794 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1795 to make sure the programs of the foreign distro will not end up loading
1796 incompatible locale data.
1799 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1800 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1801 should your Guix profile contain a mixture of programs linked against
1802 different libc version, each libc version will only try to load locale
1803 data in the right format.
1806 This is important because the locale data format used by different libc
1807 versions may be incompatible.
1809 @subsection Name Service Switch
1811 @cindex name service switch, glibc
1812 @cindex NSS (name service switch), glibc
1813 @cindex nscd (name service caching daemon)
1814 @cindex name service caching daemon (nscd)
1815 When using Guix on a foreign distro, we @emph{strongly recommend} that
1816 the system run the GNU C library's @dfn{name service cache daemon},
1817 @command{nscd}, which should be listening on the
1818 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1819 installed with Guix may fail to look up host names or user accounts, or
1820 may even crash. The next paragraphs explain why.
1822 @cindex @file{nsswitch.conf}
1823 The GNU C library implements a @dfn{name service switch} (NSS), which is
1824 an extensible mechanism for ``name lookups'' in general: host name
1825 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1826 The GNU C Library Reference Manual}).
1828 @cindex Network information service (NIS)
1829 @cindex NIS (Network information service)
1830 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1831 lookup implementations: for example, the @code{nss-mdns} plugin allow
1832 resolution of @code{.local} host names, the @code{nis} plugin allows
1833 user account lookup using the Network information service (NIS), and so
1834 on. These extra ``lookup services'' are configured system-wide in
1835 @file{/etc/nsswitch.conf}, and all the programs running on the system
1836 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1839 When they perform a name lookup---for instance by calling the
1840 @code{getaddrinfo} function in C---applications first try to connect to
1841 the nscd; on success, nscd performs name lookups on their behalf. If
1842 the nscd is not running, then they perform the name lookup by
1843 themselves, by loading the name lookup services into their own address
1844 space and running it. These name lookup services---the
1845 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1846 the host system's C library, rather than from the C library the
1847 application is linked against (the C library coming from Guix).
1849 And this is where the problem is: if your application is linked against
1850 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1851 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1852 likely crash or have its name lookups fail unexpectedly.
1854 Running @command{nscd} on the system, among other advantages, eliminates
1855 this binary incompatibility problem because those @code{libnss_*.so}
1856 files are loaded in the @command{nscd} process, not in applications
1859 @subsection X11 Fonts
1862 The majority of graphical applications use Fontconfig to locate and
1863 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1864 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1865 by default. Thus, to allow graphical applications installed with Guix
1866 to display fonts, you have to install fonts with Guix as well.
1867 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1868 @code{font-gnu-freefont}.
1870 @cindex @code{fc-cache}
1872 Once you have installed or removed fonts, or when you notice an
1873 application that does not find fonts, you may need to install Fontconfig
1874 and to force an update of its font cache by running:
1877 guix install fontconfig
1881 To display text written in Chinese languages, Japanese, or Korean in
1882 graphical applications, consider installing
1883 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1884 has multiple outputs, one per language family (@pxref{Packages with
1885 Multiple Outputs}). For instance, the following command installs fonts
1886 for Chinese languages:
1889 guix install font-adobe-source-han-sans:cn
1892 @cindex @code{xterm}
1893 Older programs such as @command{xterm} do not use Fontconfig and instead
1894 rely on server-side font rendering. Such programs require to specify a
1895 full name of a font using XLFD (X Logical Font Description), like this:
1898 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1901 To be able to use such full names for the TrueType fonts installed in
1902 your Guix profile, you need to extend the font path of the X server:
1904 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1905 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1907 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1910 @cindex @code{xlsfonts}
1911 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1912 to make sure your TrueType fonts are listed there.
1915 @subsection X.509 Certificates
1917 @cindex @code{nss-certs}
1918 The @code{nss-certs} package provides X.509 certificates, which allow
1919 programs to authenticate Web servers accessed over HTTPS.
1921 When using Guix on a foreign distro, you can install this package and
1922 define the relevant environment variables so that packages know where to
1923 look for certificates. @xref{X.509 Certificates}, for detailed
1926 @subsection Emacs Packages
1928 @cindex @code{emacs}
1929 When you install Emacs packages with Guix, the Elisp files are placed
1930 under the @file{share/emacs/site-lisp/} directory of the profile in
1931 which they are installed. The Elisp libraries are made available to
1932 Emacs through the @env{EMACSLOADPATH} environment variable, which is
1933 set when installing Emacs itself.
1935 Additionally, autoload definitions are automatically evaluated at the
1936 initialization of Emacs, by the Guix-specific
1937 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
1938 want to avoid auto-loading the Emacs packages installed with Guix, you
1939 can do so by running Emacs with the @option{--no-site-file} option
1940 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1943 @node Upgrading Guix
1944 @section Upgrading Guix
1946 @cindex Upgrading Guix, on a foreign distro
1948 To upgrade Guix, run:
1954 @xref{Invoking guix pull}, for more information.
1956 @cindex upgrading Guix for the root user, on a foreign distro
1957 @cindex upgrading the Guix daemon, on a foreign distro
1958 @cindex @command{guix pull} for the root user, on a foreign distro
1960 On a foreign distro, you can upgrade the build daemon by running:
1967 followed by (assuming your distro uses the systemd service management
1971 systemctl restart guix-daemon.service
1974 On Guix System, upgrading the daemon is achieved by reconfiguring the
1975 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
1979 @c *********************************************************************
1980 @node System Installation
1981 @chapter System Installation
1983 @cindex installing Guix System
1984 @cindex Guix System, installation
1985 This section explains how to install Guix System
1986 on a machine. Guix, as a package manager, can
1987 also be installed on top of a running GNU/Linux system,
1988 @pxref{Installation}.
1992 @c This paragraph is for people reading this from tty2 of the
1993 @c installation image.
1994 You are reading this documentation with an Info reader. For details on
1995 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1996 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1997 Info}. Hit @kbd{l} afterwards to come back here.
1999 Alternatively, run @command{info info} in another tty to keep the manual
2005 * Limitations:: What you can expect.
2006 * Hardware Considerations:: Supported hardware.
2007 * USB Stick and DVD Installation:: Preparing the installation medium.
2008 * Preparing for Installation:: Networking, partitioning, etc.
2009 * Guided Graphical Installation:: Easy graphical installation.
2010 * Manual Installation:: Manual installation for wizards.
2011 * After System Installation:: When installation succeeded.
2012 * Installing Guix in a VM:: Guix System playground.
2013 * Building the Installation Image:: How this comes to be.
2017 @section Limitations
2019 We consider Guix System to be ready for a wide range of ``desktop'' and server
2020 use cases. The reliability guarantees it provides---transactional upgrades
2021 and rollbacks, reproducibility---make it a solid foundation.
2023 Nevertheless, before you proceed with the installation, be aware of the
2024 following noteworthy limitations applicable to version @value{VERSION}:
2028 More and more system services are provided (@pxref{Services}), but some
2032 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
2033 as well as a number of X11 window managers. However, KDE is currently
2037 More than a disclaimer, this is an invitation to report issues (and success
2038 stories!), and to join us in improving it. @xref{Contributing}, for more
2042 @node Hardware Considerations
2043 @section Hardware Considerations
2045 @cindex hardware support on Guix System
2046 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
2047 builds around the kernel Linux-libre, which means that only hardware for
2048 which free software drivers and firmware exist is supported. Nowadays,
2049 a wide range of off-the-shelf hardware is supported on
2050 GNU/Linux-libre---from keyboards to graphics cards to scanners and
2051 Ethernet controllers. Unfortunately, there are still areas where
2052 hardware vendors deny users control over their own computing, and such
2053 hardware is not supported on Guix System.
2055 @cindex WiFi, hardware support
2056 One of the main areas where free drivers or firmware are lacking is WiFi
2057 devices. WiFi devices known to work include those using Atheros chips
2058 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
2059 driver, and those using Broadcom/AirForce chips (BCM43xx with
2060 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
2061 Linux-libre driver. Free firmware exists for both and is available
2062 out-of-the-box on Guix System, as part of @code{%base-firmware}
2063 (@pxref{operating-system Reference, @code{firmware}}).
2065 @cindex RYF, Respects Your Freedom
2066 The @uref{https://www.fsf.org/, Free Software Foundation} runs
2067 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
2068 certification program for hardware products that respect your freedom
2069 and your privacy and ensure that you have control over your device. We
2070 encourage you to check the list of RYF-certified devices.
2072 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
2073 web site. It contains a catalog of hardware devices with information
2074 about their support in GNU/Linux.
2077 @node USB Stick and DVD Installation
2078 @section USB Stick and DVD Installation
2080 An ISO-9660 installation image that can be written to a USB stick or
2081 burnt to a DVD can be downloaded from
2082 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz},
2083 where you can replace @code{x86_64-linux} with one of:
2087 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
2090 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
2093 @c start duplication of authentication part from ``Binary Installation''
2094 Make sure to download the associated @file{.sig} file and to verify the
2095 authenticity of the image against it, along these lines:
2098 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
2099 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
2102 If that command fails because you do not have the required public key,
2103 then run this command to import it:
2106 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
2107 -qO - | gpg --import -
2111 and rerun the @code{gpg --verify} command.
2113 Take note that a warning like ``This key is not certified with a trusted
2114 signature!'' is normal.
2118 This image contains the tools necessary for an installation.
2119 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
2121 @unnumberedsubsec Copying to a USB Stick
2123 To copy the image to a USB stick, follow these steps:
2127 Decompress the image using the @command{xz} command:
2130 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
2134 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
2135 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
2136 copy the image with:
2139 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX status=progress
2143 Access to @file{/dev/sdX} usually requires root privileges.
2146 @unnumberedsubsec Burning on a DVD
2148 To copy the image to a DVD, follow these steps:
2152 Decompress the image using the @command{xz} command:
2155 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
2159 Insert a blank DVD into your machine, and determine
2160 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
2161 copy the image with:
2164 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
2167 Access to @file{/dev/srX} usually requires root privileges.
2170 @unnumberedsubsec Booting
2172 Once this is done, you should be able to reboot the system and boot from
2173 the USB stick or DVD@. The latter usually requires you to get in the
2174 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2175 In order to boot from Libreboot, switch to the command mode by pressing
2176 the @kbd{c} key and type @command{search_grub usb}.
2178 @xref{Installing Guix in a VM}, if, instead, you would like to install
2179 Guix System in a virtual machine (VM).
2182 @node Preparing for Installation
2183 @section Preparing for Installation
2185 Once you have booted, you can use the guided graphical installer, which makes
2186 it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
2187 if you are already familiar with GNU/Linux and if you want more control than
2188 what the graphical installer provides, you can choose the ``manual''
2189 installation process (@pxref{Manual Installation}).
2191 The graphical installer is available on TTY1. You can obtain root shells on
2192 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2193 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2194 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2195 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2196 which allows you to select text with the left mouse button and to paste it
2197 with the middle button.
2200 Installation requires access to the Internet so that any missing
2201 dependencies of your system configuration can be downloaded. See the
2202 ``Networking'' section below.
2205 @node Guided Graphical Installation
2206 @section Guided Graphical Installation
2208 The graphical installer is a text-based user interface. It will guide you,
2209 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2211 The first dialog boxes allow you to set up the system as you use it during the
2212 installation: you can choose the language, keyboard layout, and set up
2213 networking, which will be used during the installation. The image below shows
2214 the networking dialog.
2216 @image{images/installer-network,5in,, networking setup with the graphical installer}
2218 Later steps allow you to partition your hard disk, as shown in the image
2219 below, to choose whether or not to use encrypted file systems, to enter the
2220 host name and root password, and to create an additional account, among other
2223 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2225 Note that, at any time, the installer allows you to exit the current
2226 installation step and resume at a previous step, as show in the image below.
2228 @image{images/installer-resume,5in,, resuming the installation process}
2230 Once you're done, the installer produces an operating system configuration and
2231 displays it (@pxref{Using the Configuration System}). At that point you can
2232 hit ``OK'' and installation will proceed. On success, you can reboot into the
2233 new system and enjoy. @xref{After System Installation}, for what's next!
2236 @node Manual Installation
2237 @section Manual Installation
2239 This section describes how you would ``manually'' install GNU@tie{}Guix System
2240 on your machine. This option requires familiarity with GNU/Linux, with the
2241 shell, and with common administration tools. If you think this is not for
2242 you, consider using the guided graphical installer (@pxref{Guided Graphical
2245 The installation system provides root shells on TTYs 3 to 6; press
2246 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2247 many common tools needed to install the system. But it is also a full-blown
2248 Guix System, which means that you can install additional packages, should you
2249 need it, using @command{guix package} (@pxref{Invoking guix package}).
2252 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2253 * Proceeding with the Installation:: Installing.
2256 @node Keyboard Layout and Networking and Partitioning
2257 @subsection Keyboard Layout, Networking, and Partitioning
2259 Before you can install the system, you may want to adjust the keyboard layout,
2260 set up networking, and partition your target hard disk. This section will
2261 guide you through this.
2263 @subsubsection Keyboard Layout
2265 @cindex keyboard layout
2266 The installation image uses the US qwerty keyboard layout. If you want
2267 to change it, you can use the @command{loadkeys} command. For example,
2268 the following command selects the Dvorak keyboard layout:
2274 See the files under @file{/run/current-system/profile/share/keymaps} for
2275 a list of available keyboard layouts. Run @command{man loadkeys} for
2278 @subsubsection Networking
2280 Run the following command to see what your network interfaces are called:
2287 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2293 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2294 Wired interfaces have a name starting with @samp{e}; for example, the
2295 interface corresponding to the first on-board Ethernet controller is
2296 called @samp{eno1}. Wireless interfaces have a name starting with
2297 @samp{w}, like @samp{w1p2s0}.
2300 @item Wired connection
2301 To configure a wired network run the following command, substituting
2302 @var{interface} with the name of the wired interface you want to use.
2305 ifconfig @var{interface} up
2309 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2312 ip link set @var{interface} up
2315 @item Wireless connection
2318 To configure wireless networking, you can create a configuration file
2319 for the @command{wpa_supplicant} configuration tool (its location is not
2320 important) using one of the available text editors such as
2324 nano wpa_supplicant.conf
2327 As an example, the following stanza can go to this file and will work
2328 for many wireless networks, provided you give the actual SSID and
2329 passphrase for the network you are connecting to:
2333 ssid="@var{my-ssid}"
2335 psk="the network's secret passphrase"
2339 Start the wireless service and run it in the background with the
2340 following command (substitute @var{interface} with the name of the
2341 network interface you want to use):
2344 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2347 Run @command{man wpa_supplicant} for more information.
2351 At this point, you need to acquire an IP address. On a network where IP
2352 addresses are automatically assigned @i{via} DHCP, you can run:
2355 dhclient -v @var{interface}
2358 Try to ping a server to see if networking is up and running:
2364 Setting up network access is almost always a requirement because the
2365 image does not contain all the software and tools that may be needed.
2367 @cindex proxy, during system installation
2368 If you need HTTP and HTTPS access to go through a proxy, run the
2372 herd set-http-proxy guix-daemon @var{URL}
2376 where @var{URL} is the proxy URL, for example
2377 @code{http://example.org:8118}.
2379 @cindex installing over SSH
2380 If you want to, you can continue the installation remotely by starting
2384 herd start ssh-daemon
2387 Make sure to either set a password with @command{passwd}, or configure
2388 OpenSSH public key authentication before logging in.
2390 @subsubsection Disk Partitioning
2392 Unless this has already been done, the next step is to partition, and
2393 then format the target partition(s).
2395 The installation image includes several partitioning tools, including
2396 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2397 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2398 the partition layout you want:
2404 If your disk uses the GUID Partition Table (GPT) format and you plan to
2405 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2406 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2409 @cindex EFI, installation
2410 @cindex UEFI, installation
2411 @cindex ESP, EFI system partition
2412 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2413 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2414 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2417 parted /dev/sda set 1 esp on
2421 @vindex grub-bootloader
2422 @vindex grub-efi-bootloader
2423 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2424 @file{/sys/firmware/efi} exists in the installation image, then you should
2425 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2426 Otherwise you should use the BIOS-based GRUB, known as
2427 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2431 Once you are done partitioning the target hard disk drive, you have to
2432 create a file system on the relevant partition(s)@footnote{Currently
2433 Guix System only supports ext4, btrfs, JFS, and F2FS file systems. In
2434 particular, code that reads file system UUIDs and labels only works for these
2435 file system types.}. For the ESP, if you have one and assuming it is
2436 @file{/dev/sda1}, run:
2439 mkfs.fat -F32 /dev/sda1
2442 For the root file system, ext4 is the most widely used format. Other
2443 file systems, such as Btrfs, support compression, which is reported to
2444 nicely complement file deduplication that the daemon performs
2445 independently of the file system (@pxref{Invoking guix-daemon,
2448 Preferably, assign file systems a label so that you can easily and
2449 reliably refer to them in @code{file-system} declarations (@pxref{File
2450 Systems}). This is typically done using the @code{-L} option of
2451 @command{mkfs.ext4} and related commands. So, assuming the target root
2452 partition lives at @file{/dev/sda2}, a file system with the label
2453 @code{my-root} can be created with:
2456 mkfs.ext4 -L my-root /dev/sda2
2459 @cindex encrypted disk
2460 If you are instead planning to encrypt the root partition, you can use
2461 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2462 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2463 @code{man cryptsetup}} for more information). Assuming you want to
2464 store the root partition on @file{/dev/sda2}, the command sequence would
2465 be along these lines:
2468 cryptsetup luksFormat /dev/sda2
2469 cryptsetup open --type luks /dev/sda2 my-partition
2470 mkfs.ext4 -L my-root /dev/mapper/my-partition
2473 Once that is done, mount the target file system under @file{/mnt}
2474 with a command like (again, assuming @code{my-root} is the label of the
2478 mount LABEL=my-root /mnt
2481 Also mount any other file systems you would like to use on the target
2482 system relative to this path. If you have opted for @file{/boot/efi} as an
2483 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2484 found by @code{guix system init} afterwards.
2486 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2487 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2488 sure to initialize them with @command{mkswap}. Assuming you have one
2489 swap partition on @file{/dev/sda3}, you would run:
2496 Alternatively, you may use a swap file. For example, assuming that in
2497 the new system you want to use the file @file{/swapfile} as a swap file,
2498 you would run@footnote{This example will work for many types of file
2499 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2500 btrfs), the required steps may be different. For details, see the
2501 manual pages for @command{mkswap} and @command{swapon}.}:
2504 # This is 10 GiB of swap space. Adjust "count" to change the size.
2505 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2506 # For security, make the file readable and writable only by root.
2507 chmod 600 /mnt/swapfile
2508 mkswap /mnt/swapfile
2509 swapon /mnt/swapfile
2512 Note that if you have encrypted the root partition and created a swap
2513 file in its file system as described above, then the encryption also
2514 protects the swap file, just like any other file in that file system.
2516 @node Proceeding with the Installation
2517 @subsection Proceeding with the Installation
2519 With the target partitions ready and the target root mounted on
2520 @file{/mnt}, we're ready to go. First, run:
2523 herd start cow-store /mnt
2526 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2527 during the installation phase are written to the target disk on @file{/mnt}
2528 rather than kept in memory. This is necessary because the first phase of
2529 the @command{guix system init} command (see below) entails downloads or
2530 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2532 Next, you have to edit a file and
2533 provide the declaration of the operating system to be installed. To
2534 that end, the installation system comes with three text editors. We
2535 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2536 supports syntax highlighting and parentheses matching; other editors
2537 include GNU Zile (an Emacs clone), and
2538 nvi (a clone of the original BSD @command{vi} editor).
2539 We strongly recommend storing that file on the target root file system, say,
2540 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2541 configuration file once you have rebooted into the newly-installed system.
2543 @xref{Using the Configuration System}, for an overview of the
2544 configuration file. The example configurations discussed in that
2545 section are available under @file{/etc/configuration} in the
2546 installation image. Thus, to get started with a system configuration
2547 providing a graphical display server (a ``desktop'' system), you can run
2548 something along these lines:
2552 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2553 # nano /mnt/etc/config.scm
2556 You should pay attention to what your configuration file contains, and
2561 Make sure the @code{bootloader-configuration} form refers to the target
2562 you want to install GRUB on. It should mention @code{grub-bootloader} if
2563 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2564 for newer UEFI systems. For legacy systems, the @code{target} field
2565 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2566 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2567 currently mounted and a @code{file-system} entry is specified in your
2571 Be sure that your file system labels match the value of their respective
2572 @code{device} fields in your @code{file-system} configuration, assuming
2573 your @code{file-system} configuration uses the @code{file-system-label}
2574 procedure in its @code{device} field.
2577 If there are encrypted or RAID partitions, make sure to add a
2578 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2581 Once you are done preparing the configuration file, the new system must
2582 be initialized (remember that the target root file system is mounted
2586 guix system init /mnt/etc/config.scm /mnt
2590 This copies all the necessary files and installs GRUB on
2591 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2592 more information, @pxref{Invoking guix system}. This command may trigger
2593 downloads or builds of missing packages, which can take some time.
2595 Once that command has completed---and hopefully succeeded!---you can run
2596 @command{reboot} and boot into the new system. The @code{root} password
2597 in the new system is initially empty; other users' passwords need to be
2598 initialized by running the @command{passwd} command as @code{root},
2599 unless your configuration specifies otherwise
2600 (@pxref{user-account-password, user account passwords}).
2601 @xref{After System Installation}, for what's next!
2604 @node After System Installation
2605 @section After System Installation
2607 Success, you've now booted into Guix System! From then on, you can update the
2608 system whenever you want by running, say:
2612 sudo guix system reconfigure /etc/config.scm
2616 This builds a new system generation with the latest packages and services
2617 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2618 your system includes the latest security updates (@pxref{Security Updates}).
2620 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2622 @cindex sudo vs. @command{guix pull}
2623 Note that @command{sudo guix} runs your user's @command{guix} command and
2624 @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
2625 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2627 The difference matters here, because @command{guix pull} updates
2628 the @command{guix} command and package definitions only for the user it is ran
2629 as. This means that if you choose to use @command{guix system reconfigure} in
2630 root's login shell, you'll need to @command{guix pull} separately.
2633 Now, @pxref{Getting Started}, and
2634 join us on @code{#guix} on the Freenode IRC network or on
2635 @email{guix-devel@@gnu.org} to share your experience!
2638 @node Installing Guix in a VM
2639 @section Installing Guix in a Virtual Machine
2641 @cindex virtual machine, Guix System installation
2642 @cindex virtual private server (VPS)
2643 @cindex VPS (virtual private server)
2644 If you'd like to install Guix System in a virtual machine (VM) or on a
2645 virtual private server (VPS) rather than on your beloved machine, this
2648 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2649 disk image, follow these steps:
2653 First, retrieve and decompress the Guix system installation image as
2654 described previously (@pxref{USB Stick and DVD Installation}).
2657 Create a disk image that will hold the installed system. To make a
2658 qcow2-formatted disk image, use the @command{qemu-img} command:
2661 qemu-img create -f qcow2 guix-system.img 50G
2664 The resulting file will be much smaller than 50 GB (typically less than
2665 1 MB), but it will grow as the virtualized storage device is filled up.
2668 Boot the USB installation image in an VM:
2671 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2672 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2673 -drive file=guix-system.img \
2674 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2677 @code{-enable-kvm} is optional, but significantly improves performance,
2678 @pxref{Running Guix in a VM}.
2681 You're now root in the VM, proceed with the installation process.
2682 @xref{Preparing for Installation}, and follow the instructions.
2685 Once installation is complete, you can boot the system that's on your
2686 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2689 @node Building the Installation Image
2690 @section Building the Installation Image
2692 @cindex installation image
2693 The installation image described above was built using the @command{guix
2694 system} command, specifically:
2697 guix system image -t iso9660 gnu/system/install.scm
2700 Have a look at @file{gnu/system/install.scm} in the source tree,
2701 and see also @ref{Invoking guix system} for more information
2702 about the installation image.
2704 @section Building the Installation Image for ARM Boards
2706 Many ARM boards require a specific variant of the
2707 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2709 If you build a disk image and the bootloader is not available otherwise
2710 (on another boot drive etc), it's advisable to build an image that
2711 includes the bootloader, specifically:
2714 guix system image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2717 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2718 board, a list of possible boards will be printed.
2720 @c *********************************************************************
2721 @node Getting Started
2722 @chapter Getting Started
2724 Presumably, you've reached this section because either you have
2725 installed Guix on top of another distribution (@pxref{Installation}), or
2726 you've installed the standalone Guix System (@pxref{System
2727 Installation}). It's time for you to get started using Guix and this
2728 section aims to help you do that and give you a feel of what it's like.
2730 Guix is about installing software, so probably the first thing you'll
2731 want to do is to actually look for software. Let's say you're looking
2732 for a text editor, you can run:
2735 guix search text editor
2738 This command shows you a number of matching @dfn{packages}, each time
2739 showing the package's name, version, a description, and additional info.
2740 Once you've found out the one you want to use, let's say Emacs (ah ha!),
2741 you can go ahead and install it (run this command as a regular user,
2742 @emph{no need for root privileges}!):
2748 You've installed your first package, congrats! In the process, you've
2749 probably noticed that Guix downloaded pre-built binaries; or, if you
2750 explicitly chose to @emph{not} use pre-built binaries, then probably
2751 Guix is still building software (@pxref{Substitutes}, for more info).
2753 Unless you're using Guix System, the @command{guix install} command must
2754 have printed this hint:
2757 hint: Consider setting the necessary environment variables by running:
2759 GUIX_PROFILE="$HOME/.guix-profile"
2760 . "$GUIX_PROFILE/etc/profile"
2762 Alternately, see `guix package --search-paths -p "$HOME/.guix-profile"'.
2765 Indeed, you must now tell your shell where @command{emacs} and other
2766 programs installed with Guix are to be found. Pasting the two lines
2767 above will do just that: it will add
2768 @code{$HOME/.guix-profile/bin}---which is where the installed package
2769 is---to the @code{PATH} environment variable. You can paste these two
2770 lines in your shell so they take effect right away, but more importantly
2771 you should add them to @file{~/.bash_profile} (or equivalent file if you
2772 do not use Bash) so that environment variables are set next time you
2773 spawn a shell. You only need to do this once and other search paths
2774 environment variables will be taken care of similarly---e.g., if you
2775 eventually install @code{python} and Python libraries, @code{PYTHONPATH}
2778 You can go on installing packages at your will. To list installed
2782 guix package --list-installed
2785 To remove a package, you would unsurprisingly run @command{guix remove}.
2786 A distinguishing feature is the ability to @dfn{roll back} any operation
2787 you made---installation, removal, upgrade---by simply typing:
2790 guix package --roll-back
2793 This is because each operation is in fact a @dfn{transaction} that
2794 creates a new @dfn{generation}. These generations and the difference
2795 between them can be displayed by running:
2798 guix package --list-generations
2801 Now you know the basics of package management!
2803 @quotation Going further
2804 @xref{Package Management}, for more about package management. You may
2805 like @dfn{declarative} package management with @command{guix package
2806 --manifest}, managing separate @dfn{profiles} with @option{--profile},
2807 deleting old generations, collecting garbage, and other nifty features
2808 that will come in handy as you become more familiar with Guix. If you
2809 are a developer, @pxref{Development} for additional tools. And if
2810 you're curious, @pxref{Features}, to peek under the hood.
2813 Once you've installed a set of packages, you will want to periodically
2814 @emph{upgrade} them to the latest and greatest version. To do that, you
2815 will first pull the latest revision of Guix and its package collection:
2821 The end result is a new @command{guix} command, under
2822 @file{~/.config/guix/current/bin}. Unless you're on Guix System, the
2823 first time you run @command{guix pull}, be sure to follow the hint that
2824 the command prints and, similar to what we saw above, paste these two
2825 lines in your terminal and @file{.bash_profile}:
2828 GUIX_PROFILE="$HOME/.config/guix/current"
2829 . "$GUIX_PROFILE/etc/profile"
2833 You must also instruct your shell to point to this new @command{guix}:
2839 At this point, you're running a brand new Guix. You can thus go ahead
2840 and actually upgrade all the packages you previously installed:
2846 As you run this command, you will see that binaries are downloaded (or
2847 perhaps some packages are built), and eventually you end up with the
2848 upgraded packages. Should one of these upgraded packages not be to your
2849 liking, remember you can always roll back!
2851 You can display the exact revision of Guix you're currently using by
2858 The information it displays is @emph{all it takes to reproduce the exact
2859 same Guix}, be it at a different point in time or on a different
2862 @quotation Going further
2863 @xref{Invoking guix pull}, for more information. @xref{Channels}, on
2864 how to specify additional @dfn{channels} to pull packages from, how to
2865 replicate Guix, and more. You may also find @command{time-machine}
2866 handy (@pxref{Invoking guix time-machine}).
2869 If you installed Guix System, one of the first things you'll want to do
2870 is to upgrade your system. Once you've run @command{guix pull} to get
2871 the latest Guix, you can upgrade the system like this:
2874 sudo guix system reconfigure /etc/config.scm
2877 Upon completion, the system runs the latest versions of its software
2878 packages. When you eventually reboot, you'll notice a sub-menu in the
2879 bootloader that reads ``Old system generations'': it's what allows you
2880 to boot @emph{an older generation of your system}, should the latest
2881 generation be ``broken'' or otherwise unsatisfying. Just like for
2882 packages, you can always @emph{roll back} to a previous generation
2883 @emph{of the whole system}:
2886 sudo guix system roll-back
2889 There are many things you'll probably want to tweak on your system:
2890 adding new user accounts, adding new system services, fiddling with the
2891 configuration of those services, etc. The system configuration is
2892 @emph{entirely} described in the @file{/etc/config.scm} file.
2893 @xref{Using the Configuration System}, to learn how to change it.
2895 Now you know enough to get started!
2897 @quotation Resources
2898 The rest of this manual provides a reference for all things Guix. Here
2899 are some additional resources you may find useful:
2903 @xref{Top,,, guix-cookbook, The GNU Guix Cookbook}, for a list of
2904 ``how-to'' style of recipes for a variety of applications.
2907 The @uref{https://guix.gnu.org/guix-refcard.pdf, GNU Guix Reference
2908 Card} lists in two pages most of the commands and options you'll ever
2912 The web site contains @uref{https://guix.gnu.org/en/videos/,
2913 instructional videos} covering topics such as everyday use of Guix, how
2914 to get help, and how to become a contributor.
2917 @xref{Documentation}, to learn how to access documentation on your
2921 We hope you will enjoy Guix as much as the community enjoys building it!
2924 @c *********************************************************************
2925 @node Package Management
2926 @chapter Package Management
2929 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2930 remove software packages, without having to know about their build
2931 procedures or dependencies. Guix also goes beyond this obvious set of
2934 This chapter describes the main features of Guix, as well as the
2935 package management tools it provides. Along with the command-line
2936 interface described below (@pxref{Invoking guix package, @code{guix
2937 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2938 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2939 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2943 guix install emacs-guix
2947 * Features:: How Guix will make your life brighter.
2948 * Invoking guix package:: Package installation, removal, etc.
2949 * Substitutes:: Downloading pre-built binaries.
2950 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2951 * Invoking guix gc:: Running the garbage collector.
2952 * Invoking guix pull:: Fetching the latest Guix and distribution.
2953 * Invoking guix time-machine:: Running an older revision of Guix.
2954 * Inferiors:: Interacting with another revision of Guix.
2955 * Invoking guix describe:: Display information about your Guix revision.
2956 * Invoking guix archive:: Exporting and importing store files.
2962 Here we assume you've already made your first steps with Guix
2963 (@pxref{Getting Started}) and would like to get an overview about what's
2964 going on under the hood.
2966 When using Guix, each package ends up in the @dfn{package store}, in its
2967 own directory---something that resembles
2968 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2970 Instead of referring to these directories, users have their own
2971 @dfn{profile}, which points to the packages that they actually want to
2972 use. These profiles are stored within each user's home directory, at
2973 @code{$HOME/.guix-profile}.
2975 For example, @code{alice} installs GCC 4.7.2. As a result,
2976 @file{/home/alice/.guix-profile/bin/gcc} points to
2977 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2978 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2979 simply continues to point to
2980 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2981 coexist on the same system without any interference.
2983 The @command{guix package} command is the central tool to manage
2984 packages (@pxref{Invoking guix package}). It operates on the per-user
2985 profiles, and can be used @emph{with normal user privileges}.
2987 @cindex transactions
2988 The command provides the obvious install, remove, and upgrade
2989 operations. Each invocation is actually a @emph{transaction}: either
2990 the specified operation succeeds, or nothing happens. Thus, if the
2991 @command{guix package} process is terminated during the transaction,
2992 or if a power outage occurs during the transaction, then the user's
2993 profile remains in its previous state, and remains usable.
2995 In addition, any package transaction may be @emph{rolled back}. So, if,
2996 for example, an upgrade installs a new version of a package that turns
2997 out to have a serious bug, users may roll back to the previous instance
2998 of their profile, which was known to work well. Similarly, the global
2999 system configuration on Guix is subject to
3000 transactional upgrades and roll-back
3001 (@pxref{Using the Configuration System}).
3003 All packages in the package store may be @emph{garbage-collected}.
3004 Guix can determine which packages are still referenced by user
3005 profiles, and remove those that are provably no longer referenced
3006 (@pxref{Invoking guix gc}). Users may also explicitly remove old
3007 generations of their profile so that the packages they refer to can be
3010 @cindex reproducibility
3011 @cindex reproducible builds
3012 Guix takes a @dfn{purely functional} approach to package
3013 management, as described in the introduction (@pxref{Introduction}).
3014 Each @file{/gnu/store} package directory name contains a hash of all the
3015 inputs that were used to build that package---compiler, libraries, build
3016 scripts, etc. This direct correspondence allows users to make sure a
3017 given package installation matches the current state of their
3018 distribution. It also helps maximize @dfn{build reproducibility}:
3019 thanks to the isolated build environments that are used, a given build
3020 is likely to yield bit-identical files when performed on different
3021 machines (@pxref{Invoking guix-daemon, container}).
3024 This foundation allows Guix to support @dfn{transparent binary/source
3025 deployment}. When a pre-built binary for a @file{/gnu/store} item is
3026 available from an external source---a @dfn{substitute}, Guix just
3027 downloads it and unpacks it;
3028 otherwise, it builds the package from source, locally
3029 (@pxref{Substitutes}). Because build results are usually bit-for-bit
3030 reproducible, users do not have to trust servers that provide
3031 substitutes: they can force a local build and @emph{challenge} providers
3032 (@pxref{Invoking guix challenge}).
3034 Control over the build environment is a feature that is also useful for
3035 developers. The @command{guix environment} command allows developers of
3036 a package to quickly set up the right development environment for their
3037 package, without having to manually install the dependencies of the
3038 package into their profile (@pxref{Invoking guix environment}).
3040 @cindex replication, of software environments
3041 @cindex provenance tracking, of software artifacts
3042 All of Guix and its package definitions is version-controlled, and
3043 @command{guix pull} allows you to ``travel in time'' on the history of Guix
3044 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
3045 Guix instance on a different machine or at a later point in time, which in
3046 turn allows you to @emph{replicate complete software environments}, while
3047 retaining precise @dfn{provenance tracking} of the software.
3049 @node Invoking guix package
3050 @section Invoking @command{guix package}
3052 @cindex installing packages
3053 @cindex removing packages
3054 @cindex package installation
3055 @cindex package removal
3056 The @command{guix package} command is the tool that allows users to
3057 install, upgrade, and remove packages, as well as rolling back to
3058 previous configurations. It operates only on the user's own profile,
3059 and works with normal user privileges (@pxref{Features}). Its syntax
3063 guix package @var{options}
3066 @cindex transactions
3067 Primarily, @var{options} specifies the operations to be performed during
3068 the transaction. Upon completion, a new profile is created, but
3069 previous @dfn{generations} of the profile remain available, should the user
3072 For example, to remove @code{lua} and install @code{guile} and
3073 @code{guile-cairo} in a single transaction:
3076 guix package -r lua -i guile guile-cairo
3079 @cindex aliases, for @command{guix package}
3080 For your convenience, we also provide the following aliases:
3084 @command{guix search} is an alias for @command{guix package -s},
3086 @command{guix install} is an alias for @command{guix package -i},
3088 @command{guix remove} is an alias for @command{guix package -r},
3090 @command{guix upgrade} is an alias for @command{guix package -u},
3092 and @command{guix show} is an alias for @command{guix package --show=}.
3095 These aliases are less expressive than @command{guix package} and provide
3096 fewer options, so in some cases you'll probably want to use @command{guix
3099 @command{guix package} also supports a @dfn{declarative approach}
3100 whereby the user specifies the exact set of packages to be available and
3101 passes it @i{via} the @option{--manifest} option
3102 (@pxref{profile-manifest, @option{--manifest}}).
3105 For each user, a symlink to the user's default profile is automatically
3106 created in @file{$HOME/.guix-profile}. This symlink always points to the
3107 current generation of the user's default profile. Thus, users can add
3108 @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
3109 variable, and so on.
3110 @cindex search paths
3111 If you are not using Guix System, consider adding the
3112 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
3113 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
3114 shells get all the right environment variable definitions:
3117 GUIX_PROFILE="$HOME/.guix-profile" ; \
3118 source "$GUIX_PROFILE/etc/profile"
3121 In a multi-user setup, user profiles are stored in a place registered as
3122 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
3123 to (@pxref{Invoking guix gc}). That directory is normally
3124 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
3125 @var{localstatedir} is the value passed to @code{configure} as
3126 @option{--localstatedir}, and @var{user} is the user name. The
3127 @file{per-user} directory is created when @command{guix-daemon} is
3128 started, and the @var{user} sub-directory is created by @command{guix
3131 The @var{options} can be among the following:
3135 @item --install=@var{package} @dots{}
3136 @itemx -i @var{package} @dots{}
3137 Install the specified @var{package}s.
3139 Each @var{package} may specify either a simple package name, such as
3140 @code{guile}, or a package name followed by an at-sign and version number,
3141 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
3142 case, the newest version prefixed by @code{1.8} is selected).
3144 If no version number is specified, the
3145 newest available version will be selected. In addition, @var{package}
3146 may contain a colon, followed by the name of one of the outputs of the
3147 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
3148 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
3149 name (and optionally version) are searched for among the GNU
3150 distribution modules (@pxref{Package Modules}).
3152 @cindex propagated inputs
3153 Sometimes packages have @dfn{propagated inputs}: these are dependencies
3154 that automatically get installed along with the required package
3155 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
3156 @code{package} objects}, for information about propagated inputs in
3157 package definitions).
3159 @anchor{package-cmd-propagated-inputs}
3160 An example is the GNU MPC library: its C header files refer to those of
3161 the GNU MPFR library, which in turn refer to those of the GMP library.
3162 Thus, when installing MPC, the MPFR and GMP libraries also get installed
3163 in the profile; removing MPC also removes MPFR and GMP---unless they had
3164 also been explicitly installed by the user.
3166 Besides, packages sometimes rely on the definition of environment
3167 variables for their search paths (see explanation of
3168 @option{--search-paths} below). Any missing or possibly incorrect
3169 environment variable definitions are reported here.
3171 @item --install-from-expression=@var{exp}
3173 Install the package @var{exp} evaluates to.
3175 @var{exp} must be a Scheme expression that evaluates to a
3176 @code{<package>} object. This option is notably useful to disambiguate
3177 between same-named variants of a package, with expressions such as
3178 @code{(@@ (gnu packages base) guile-final)}.
3180 Note that this option installs the first output of the specified
3181 package, which may be insufficient when needing a specific output of a
3182 multiple-output package.
3184 @item --install-from-file=@var{file}
3185 @itemx -f @var{file}
3186 Install the package that the code within @var{file} evaluates to.
3188 As an example, @var{file} might contain a definition like this
3189 (@pxref{Defining Packages}):
3192 @include package-hello.scm
3195 Developers may find it useful to include such a @file{guix.scm} file
3196 in the root of their project source tree that can be used to test
3197 development snapshots and create reproducible development environments
3198 (@pxref{Invoking guix environment}).
3200 The @var{file} may also contain a JSON representation of one or more
3201 package definitions. Running @code{guix package -f} on
3202 @file{hello.json} with the following contents would result in installing
3203 the package @code{greeter} after building @code{myhello}:
3206 @verbatiminclude package-hello.json
3209 @item --remove=@var{package} @dots{}
3210 @itemx -r @var{package} @dots{}
3211 Remove the specified @var{package}s.
3213 As for @option{--install}, each @var{package} may specify a version number
3214 and/or output name in addition to the package name. For instance,
3215 @samp{-r glibc:debug} would remove the @code{debug} output of
3218 @item --upgrade[=@var{regexp} @dots{}]
3219 @itemx -u [@var{regexp} @dots{}]
3220 @cindex upgrading packages
3221 Upgrade all the installed packages. If one or more @var{regexp}s are
3222 specified, upgrade only installed packages whose name matches a
3223 @var{regexp}. Also see the @option{--do-not-upgrade} option below.
3225 Note that this upgrades package to the latest version of packages found
3226 in the distribution currently installed. To update your distribution,
3227 you should regularly run @command{guix pull} (@pxref{Invoking guix
3230 @cindex package transformations, upgrades
3231 When upgrading, package transformations that were originally applied
3232 when creating the profile are automatically re-applied (@pxref{Package
3233 Transformation Options}). For example, assume you first installed Emacs
3234 from the tip of its development branch with:
3237 guix install emacs-next --with-branch=emacs-next=master
3240 Next time you run @command{guix upgrade}, Guix will again pull the tip
3241 of the Emacs development branch and build @code{emacs-next} from that
3244 Note that transformation options such as @option{--with-branch} and
3245 @option{--with-source} depend on external state; it is up to you to
3246 ensure that they work as expected. You can also discard a
3247 transformations that apply to a package by running:
3250 guix install @var{package}
3253 @item --do-not-upgrade[=@var{regexp} @dots{}]
3254 When used together with the @option{--upgrade} option, do @emph{not}
3255 upgrade any packages whose name matches a @var{regexp}. For example, to
3256 upgrade all packages in the current profile except those containing the
3257 substring ``emacs'':
3260 $ guix package --upgrade . --do-not-upgrade emacs
3263 @item @anchor{profile-manifest}--manifest=@var{file}
3264 @itemx -m @var{file}
3265 @cindex profile declaration
3266 @cindex profile manifest
3267 Create a new generation of the profile from the manifest object
3268 returned by the Scheme code in @var{file}. This option can be repeated
3269 several times, in which case the manifests are concatenated.
3271 This allows you to @emph{declare} the profile's contents rather than
3272 constructing it through a sequence of @option{--install} and similar
3273 commands. The advantage is that @var{file} can be put under version
3274 control, copied to different machines to reproduce the same profile, and
3277 @c FIXME: Add reference to (guix profile) documentation when available.
3278 @var{file} must return a @dfn{manifest} object, which is roughly a list
3281 @findex packages->manifest
3283 (use-package-modules guile emacs)
3288 ;; Use a specific package output.
3289 (list guile-2.0 "debug")))
3292 @findex specifications->manifest
3293 In this example we have to know which modules define the @code{emacs}
3294 and @code{guile-2.0} variables to provide the right
3295 @code{use-package-modules} line, which can be cumbersome. We can
3296 instead provide regular package specifications and let
3297 @code{specifications->manifest} look up the corresponding package
3301 (specifications->manifest
3302 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
3305 @xref{export-manifest, @option{--export-manifest}}, to learn how to
3306 obtain a manifest file from an existing profile.
3309 @cindex rolling back
3310 @cindex undoing transactions
3311 @cindex transactions, undoing
3312 Roll back to the previous @dfn{generation} of the profile---i.e., undo
3313 the last transaction.
3315 When combined with options such as @option{--install}, roll back occurs
3316 before any other actions.
3318 When rolling back from the first generation that actually contains
3319 installed packages, the profile is made to point to the @dfn{zeroth
3320 generation}, which contains no files apart from its own metadata.
3322 After having rolled back, installing, removing, or upgrading packages
3323 overwrites previous future generations. Thus, the history of the
3324 generations in a profile is always linear.
3326 @item --switch-generation=@var{pattern}
3327 @itemx -S @var{pattern}
3329 Switch to a particular generation defined by @var{pattern}.
3331 @var{pattern} may be either a generation number or a number prefixed
3332 with ``+'' or ``-''. The latter means: move forward/backward by a
3333 specified number of generations. For example, if you want to return to
3334 the latest generation after @option{--roll-back}, use
3335 @option{--switch-generation=+1}.
3337 The difference between @option{--roll-back} and
3338 @option{--switch-generation=-1} is that @option{--switch-generation} will
3339 not make a zeroth generation, so if a specified generation does not
3340 exist, the current generation will not be changed.
3342 @item --search-paths[=@var{kind}]
3343 @cindex search paths
3344 Report environment variable definitions, in Bash syntax, that may be
3345 needed in order to use the set of installed packages. These environment
3346 variables are used to specify @dfn{search paths} for files used by some
3347 of the installed packages.
3349 For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
3350 environment variables to be defined so it can look for headers and
3351 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
3352 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
3353 library are installed in the profile, then @option{--search-paths} will
3354 suggest setting these variables to @file{@var{profile}/include} and
3355 @file{@var{profile}/lib}, respectively.
3357 The typical use case is to define these environment variables in the
3361 $ eval `guix package --search-paths`
3364 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
3365 meaning that the returned environment variable definitions will either
3366 be exact settings, or prefixes or suffixes of the current value of these
3367 variables. When omitted, @var{kind} defaults to @code{exact}.
3369 This option can also be used to compute the @emph{combined} search paths
3370 of several profiles. Consider this example:
3373 $ guix package -p foo -i guile
3374 $ guix package -p bar -i guile-json
3375 $ guix package -p foo -p bar --search-paths
3378 The last command above reports about the @env{GUILE_LOAD_PATH}
3379 variable, even though, taken individually, neither @file{foo} nor
3380 @file{bar} would lead to that recommendation.
3383 @item --profile=@var{profile}
3384 @itemx -p @var{profile}
3385 Use @var{profile} instead of the user's default profile.
3387 @var{profile} must be the name of a file that will be created upon
3388 completion. Concretely, @var{profile} will be a mere symbolic link
3389 (``symlink'') pointing to the actual profile where packages are
3393 $ guix install hello -p ~/code/my-profile
3395 $ ~/code/my-profile/bin/hello
3399 All it takes to get rid of the profile is to remove this symlink and its
3400 siblings that point to specific generations:
3403 $ rm ~/code/my-profile ~/code/my-profile-*-link
3406 @item --list-profiles
3407 List all the user's profiles:
3410 $ guix package --list-profiles
3411 /home/charlie/.guix-profile
3412 /home/charlie/code/my-profile
3413 /home/charlie/code/devel-profile
3414 /home/charlie/tmp/test
3417 When running as root, list all the profiles of all the users.
3419 @cindex collisions, in a profile
3420 @cindex colliding packages in profiles
3421 @cindex profile collisions
3422 @item --allow-collisions
3423 Allow colliding packages in the new profile. Use at your own risk!
3425 By default, @command{guix package} reports as an error @dfn{collisions}
3426 in the profile. Collisions happen when two or more different versions
3427 or variants of a given package end up in the profile.
3430 Use the bootstrap Guile to build the profile. This option is only
3431 useful to distribution developers.
3435 In addition to these actions, @command{guix package} supports the
3436 following options to query the current state of a profile, or the
3437 availability of packages:
3441 @item --search=@var{regexp}
3442 @itemx -s @var{regexp}
3443 @anchor{guix-search}
3444 @cindex searching for packages
3445 List the available packages whose name, synopsis, or description matches
3446 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3447 Print all the metadata of matching packages in
3448 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3449 GNU recutils manual}).
3451 This allows specific fields to be extracted using the @command{recsel}
3452 command, for instance:
3455 $ guix package -s malloc | recsel -p name,version,relevance
3469 Similarly, to show the name of all the packages available under the
3470 terms of the GNU@tie{}LGPL version 3:
3473 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3480 It is also possible to refine search results using several @code{-s} flags to
3481 @command{guix package}, or several arguments to @command{guix search}. For
3482 example, the following command returns a list of board games (this time using
3483 the @command{guix search} alias):
3486 $ guix search '\<board\>' game | recsel -p name
3491 If we were to omit @code{-s game}, we would also get software packages
3492 that deal with printed circuit boards; removing the angle brackets
3493 around @code{board} would further add packages that have to do with
3496 And now for a more elaborate example. The following command searches
3497 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3498 libraries, and prints the name and synopsis of the matching packages:
3501 $ guix search crypto library | \
3502 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3506 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3507 information on @dfn{selection expressions} for @code{recsel -e}.
3509 @item --show=@var{package}
3510 Show details about @var{package}, taken from the list of available packages, in
3511 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3515 $ guix package --show=python | recsel -p name,version
3523 You may also specify the full name of a package to only get details about a
3524 specific version of it (this time using the @command{guix show} alias):
3526 $ guix show python@@3.4 | recsel -p name,version
3533 @item --list-installed[=@var{regexp}]
3534 @itemx -I [@var{regexp}]
3535 List the currently installed packages in the specified profile, with the
3536 most recently installed packages shown last. When @var{regexp} is
3537 specified, list only installed packages whose name matches @var{regexp}.
3539 For each installed package, print the following items, separated by
3540 tabs: the package name, its version string, the part of the package that
3541 is installed (for instance, @code{out} for the default output,
3542 @code{include} for its headers, etc.), and the path of this package in
3545 @item --list-available[=@var{regexp}]
3546 @itemx -A [@var{regexp}]
3547 List packages currently available in the distribution for this system
3548 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3549 available packages whose name matches @var{regexp}.
3551 For each package, print the following items separated by tabs: its name,
3552 its version string, the parts of the package (@pxref{Packages with
3553 Multiple Outputs}), and the source location of its definition.
3555 @item --list-generations[=@var{pattern}]
3556 @itemx -l [@var{pattern}]
3558 Return a list of generations along with their creation dates; for each
3559 generation, show the installed packages, with the most recently
3560 installed packages shown last. Note that the zeroth generation is never
3563 For each installed package, print the following items, separated by
3564 tabs: the name of a package, its version string, the part of the package
3565 that is installed (@pxref{Packages with Multiple Outputs}), and the
3566 location of this package in the store.
3568 When @var{pattern} is used, the command returns only matching
3569 generations. Valid patterns include:
3572 @item @emph{Integers and comma-separated integers}. Both patterns denote
3573 generation numbers. For instance, @option{--list-generations=1} returns
3576 And @option{--list-generations=1,8,2} outputs three generations in the
3577 specified order. Neither spaces nor trailing commas are allowed.
3579 @item @emph{Ranges}. @option{--list-generations=2..9} prints the
3580 specified generations and everything in between. Note that the start of
3581 a range must be smaller than its end.
3583 It is also possible to omit the endpoint. For example,
3584 @option{--list-generations=2..}, returns all generations starting from the
3587 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3588 or months by passing an integer along with the first letter of the
3589 duration. For example, @option{--list-generations=20d} lists generations
3590 that are up to 20 days old.
3593 @item --delete-generations[=@var{pattern}]
3594 @itemx -d [@var{pattern}]
3595 When @var{pattern} is omitted, delete all generations except the current
3598 This command accepts the same patterns as @option{--list-generations}.
3599 When @var{pattern} is specified, delete the matching generations. When
3600 @var{pattern} specifies a duration, generations @emph{older} than the
3601 specified duration match. For instance, @option{--delete-generations=1m}
3602 deletes generations that are more than one month old.
3604 If the current generation matches, it is @emph{not} deleted. Also, the
3605 zeroth generation is never deleted.
3607 Note that deleting generations prevents rolling back to them.
3608 Consequently, this command must be used with care.
3610 @cindex manifest, exporting
3611 @anchor{export-manifest}
3612 @item --export-manifest
3613 Write to standard output a manifest suitable for @option{--manifest}
3614 corresponding to the chosen profile(s).
3616 This option is meant to help you migrate from the ``imperative''
3617 operating mode---running @command{guix install}, @command{guix upgrade},
3618 etc.---to the declarative mode that @option{--manifest} offers.
3620 Be aware that the resulting manifest @emph{approximates} what your
3621 profile actually contains; for instance, depending on how your profile
3622 was created, it can refer to packages or package versions that are not
3623 exactly what you specified.
3625 Keep in mind that a manifest is purely symbolic: it only contains
3626 package names and possibly versions, and their meaning varies over time.
3627 If you wish to ``pin'' channels to the revisions that were used to build
3628 the profile(s), see @option{--export-channels} below.
3630 @cindex pinning, channel revisions of a profile
3631 @item --export-channels
3632 Write to standard output the list of channels used by the chosen
3633 profile(s), in a format suitable for @command{guix pull --channels} or
3634 @command{guix time-machine --channels} (@pxref{Channels}).
3636 Together with @option{--export-manifest}, this option provides
3637 information allowing you to replicate the current profile
3638 (@pxref{Replicating Guix}).
3640 However, note that the output of this command @emph{approximates} what
3641 was actually used to build this profile. In particular, a single
3642 profile might have been built from several different revisions of the
3643 same channel. In that case, @option{--export-manifest} chooses the last
3644 one and writes the list of other revisions in a comment. If you really
3645 need to pick packages from different channel revisions, you can use
3646 inferiors in your manifest to do so (@pxref{Inferiors}).
3648 Together with @option{--export-manifest}, this is a good starting point
3649 if you are willing to migrate from the ``imperative'' model to the fully
3650 declarative model consisting of a manifest file along with a channels
3651 file pinning the exact channel revision(s) you want.
3654 Finally, since @command{guix package} may actually start build
3655 processes, it supports all the common build options (@pxref{Common Build
3656 Options}). It also supports package transformation options, such as
3657 @option{--with-source}, and preserves them across upgrades
3658 (@pxref{Package Transformation Options}).
3661 @section Substitutes
3664 @cindex pre-built binaries
3665 Guix supports transparent source/binary deployment, which means that it
3666 can either build things locally, or download pre-built items from a
3667 server, or both. We call these pre-built items @dfn{substitutes}---they
3668 are substitutes for local build results. In many cases, downloading a
3669 substitute is much faster than building things locally.
3671 Substitutes can be anything resulting from a derivation build
3672 (@pxref{Derivations}). Of course, in the common case, they are
3673 pre-built package binaries, but source tarballs, for instance, which
3674 also result from derivation builds, can be available as substitutes.
3677 * Official Substitute Server:: One particular source of substitutes.
3678 * Substitute Server Authorization:: How to enable or disable substitutes.
3679 * Getting Substitutes from Other Servers:: Substitute diversity.
3680 * Substitute Authentication:: How Guix verifies substitutes.
3681 * Proxy Settings:: How to get substitutes via proxy.
3682 * Substitution Failure:: What happens when substitution fails.
3683 * On Trusting Binaries:: How can you trust that binary blob?
3686 @node Official Substitute Server
3687 @subsection Official Substitute Server
3690 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3691 that builds packages from Guix continuously for some
3692 architectures, and makes them available as substitutes. This is the
3693 default source of substitutes; it can be overridden by passing the
3694 @option{--substitute-urls} option either to @command{guix-daemon}
3695 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3696 or to client tools such as @command{guix package}
3697 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3700 Substitute URLs can be either HTTP or HTTPS.
3701 HTTPS is recommended because communications are encrypted; conversely,
3702 using HTTP makes all communications visible to an eavesdropper, who
3703 could use the information gathered to determine, for instance, whether
3704 your system has unpatched security vulnerabilities.
3706 Substitutes from the official build farm are enabled by default when
3707 using Guix System (@pxref{GNU Distribution}). However,
3708 they are disabled by default when using Guix on a foreign distribution,
3709 unless you have explicitly enabled them via one of the recommended
3710 installation steps (@pxref{Installation}). The following paragraphs
3711 describe how to enable or disable substitutes for the official build
3712 farm; the same procedure can also be used to enable substitutes for any
3713 other substitute server.
3715 @node Substitute Server Authorization
3716 @subsection Substitute Server Authorization
3719 @cindex substitutes, authorization thereof
3720 @cindex access control list (ACL), for substitutes
3721 @cindex ACL (access control list), for substitutes
3722 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3724 must add its public key to the access control list (ACL) of archive
3725 imports, using the @command{guix archive} command (@pxref{Invoking guix
3726 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3727 be compromised and to serve genuine substitutes.
3730 If you are using Guix System, you can skip this section: Guix System
3731 authorizes substitutes from @code{@value{SUBSTITUTE-SERVER}} by default.
3734 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3735 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3736 the installation prefix of Guix. If you installed Guix from source,
3737 make sure you checked the GPG signature of
3738 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3739 Then, you can run something like this:
3742 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3745 Once this is in place, the output of a command like @code{guix build}
3746 should change from something like:
3749 $ guix build emacs --dry-run
3750 The following derivations would be built:
3751 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3752 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3753 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3754 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3762 $ guix build emacs --dry-run
3763 112.3 MB would be downloaded:
3764 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3765 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3766 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3767 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3772 The text changed from ``The following derivations would be built'' to
3773 ``112.3 MB would be downloaded''. This indicates that substitutes from
3774 @code{@value{SUBSTITUTE-SERVER}} are usable and will be downloaded, when
3775 possible, for future builds.
3777 @cindex substitutes, how to disable
3778 The substitute mechanism can be disabled globally by running
3779 @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
3780 guix-daemon}). It can also be disabled temporarily by passing the
3781 @option{--no-substitutes} option to @command{guix package},
3782 @command{guix build}, and other command-line tools.
3784 @node Getting Substitutes from Other Servers
3785 @subsection Getting Substitutes from Other Servers
3787 @cindex substitute servers, adding more
3788 Guix can look up and fetch substitutes from several servers. This is
3789 useful when you are using packages from additional channels for which
3790 the official server does not have substitutes but another server
3791 provides them. Another situation where this is useful is when you would
3792 prefer to download from your organization's substitute server, resorting
3793 to the official server only as a fallback or dismissing it altogether.
3795 You can give Guix a list of substitute server URLs and it will check
3796 them in the specified order. You also need to explicitly authorize the
3797 public keys of substitute servers to instruct Guix to accept the
3798 substitutes they sign.
3800 On Guix System, this is achieved by modifying the configuration of the
3801 @code{guix} service. Since the @code{guix} service is part of the
3802 default lists of services, @code{%base-services} and
3803 @code{%desktop-services}, you can use @code{modify-services} to change
3804 its configuration and add the URLs and substitute keys that you want
3805 (@pxref{Service Reference, @code{modify-services}}).
3807 As an example, suppose you want to fetch substitutes from
3808 @code{guix.example.org} and to authorize the signing key of that server,
3809 in addition to the default @code{@value{SUBSTITUTE-SERVER}}. The
3810 resulting operating system configuration will look something like:
3816 ;; Assume we're starting from '%desktop-services'. Replace it
3817 ;; with the list of services you're actually using.
3818 (modify-services %desktop-services
3819 (guix-service-type config =>
3823 (append (list "https://guix.example.org")
3824 %default-substitute-urls))
3826 (append (list (local-file "./key.pub"))
3827 %default-authorized-guix-keys)))))))
3830 This assumes that the file @file{key.pub} contains the signing key of
3831 @code{guix.example.org}. With this change in place in your operating
3832 system configuration file (say @file{/etc/config.scm}), you can
3833 reconfigure and restart the @code{guix-daemon} service or reboot so the
3834 changes take effect:
3837 $ sudo guix system reconfigure /etc/config.scm
3838 $ sudo herd restart guix-daemon
3841 If you're running Guix on a ``foreign distro'', you would instead take
3842 the following steps to get substitutes from additional servers:
3846 Edit the service configuration file for @code{guix-daemon}; when using
3847 systemd, this is normally
3848 @file{/etc/systemd/system/guix-daemon.service}. Add the
3849 @option{--substitute-urls} option on the @command{guix-daemon} command
3850 line and list the URLs of interest (@pxref{daemon-substitute-urls,
3851 @code{guix-daemon --substitute-urls}}):
3854 @dots{} --substitute-urls='https://guix.example.org https://@value{SUBSTITUTE-SERVER}'
3858 Restart the daemon. For systemd, it goes like this:
3861 systemctl daemon-reload
3862 systemctl restart guix-daemon.service
3866 Authorize the key of the new server (@pxref{Invoking guix archive}):
3869 guix archive --authorize < key.pub
3872 Again this assumes @file{key.pub} contains the public key that
3873 @code{guix.example.org} uses to sign substitutes.
3876 Now you're all set! Substitutes will be preferably taken from
3877 @code{https://guix.example.org}, using @code{@value{SUBSTITUTE-SERVER}}
3878 as a fallback. Of course you can list as many substitute servers as you
3879 like, with the caveat that substitute lookup can be slowed down if too
3880 many servers need to be contacted.
3882 Note that there are also situations where one may want to add the URL of
3883 a substitute server @emph{without} authorizing its key.
3884 @xref{Substitute Authentication}, to understand this fine point.
3886 @node Substitute Authentication
3887 @subsection Substitute Authentication
3889 @cindex digital signatures
3890 Guix detects and raises an error when attempting to use a substitute
3891 that has been tampered with. Likewise, it ignores substitutes that are
3892 not signed, or that are not signed by one of the keys listed in the ACL.
3894 There is one exception though: if an unauthorized server provides
3895 substitutes that are @emph{bit-for-bit identical} to those provided by
3896 an authorized server, then the unauthorized server becomes eligible for
3897 downloads. For example, assume we have chosen two substitute servers
3901 --substitute-urls="https://a.example.org https://b.example.org"
3905 @cindex reproducible builds
3906 If the ACL contains only the key for @samp{b.example.org}, and if
3907 @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
3908 then Guix will download substitutes from @samp{a.example.org} because it
3909 comes first in the list and can be considered a mirror of
3910 @samp{b.example.org}. In practice, independent build machines usually
3911 produce the same binaries, thanks to bit-reproducible builds (see
3914 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3915 (in other words, the server is not authenticated), contrary to what
3916 HTTPS clients such as Web browsers usually do. This is because Guix
3917 authenticates substitute information itself, as explained above, which
3918 is what we care about (whereas X.509 certificates are about
3919 authenticating bindings between domain names and public keys).
3921 @node Proxy Settings
3922 @subsection Proxy Settings
3926 Substitutes are downloaded over HTTP or HTTPS@. The @env{http_proxy} and
3927 @env{https_proxy} environment variables can be set in the environment of
3928 @command{guix-daemon} and are honored for downloads of substitutes.
3929 Note that the value of those environment variables in the environment
3930 where @command{guix build}, @command{guix package}, and other client
3931 commands are run has @emph{absolutely no effect}.
3933 @node Substitution Failure
3934 @subsection Substitution Failure
3936 Even when a substitute for a derivation is available, sometimes the
3937 substitution attempt will fail. This can happen for a variety of
3938 reasons: the substitute server might be offline, the substitute may
3939 recently have been deleted, the connection might have been interrupted,
3942 When substitutes are enabled and a substitute for a derivation is
3943 available, but the substitution attempt fails, Guix will attempt to
3944 build the derivation locally depending on whether or not
3945 @option{--fallback} was given (@pxref{fallback-option,, common build
3946 option @option{--fallback}}). Specifically, if @option{--fallback} was
3947 omitted, then no local build will be performed, and the derivation is
3948 considered to have failed. However, if @option{--fallback} was given,
3949 then Guix will attempt to build the derivation locally, and the success
3950 or failure of the derivation depends on the success or failure of the
3951 local build. Note that when substitutes are disabled or no substitute
3952 is available for the derivation in question, a local build will
3953 @emph{always} be performed, regardless of whether or not
3954 @option{--fallback} was given.
3956 To get an idea of how many substitutes are available right now, you can
3957 try running the @command{guix weather} command (@pxref{Invoking guix
3958 weather}). This command provides statistics on the substitutes provided
3961 @node On Trusting Binaries
3962 @subsection On Trusting Binaries
3964 @cindex trust, of pre-built binaries
3965 Today, each individual's control over their own computing is at the
3966 mercy of institutions, corporations, and groups with enough power and
3967 determination to subvert the computing infrastructure and exploit its
3968 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3969 convenient, we encourage users to also build on their own, or even run
3970 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3971 interesting target. One way to help is by publishing the software you
3972 build using @command{guix publish} so that others have one more choice
3973 of server to download substitutes from (@pxref{Invoking guix publish}).
3975 Guix has the foundations to maximize build reproducibility
3976 (@pxref{Features}). In most cases, independent builds of a given
3977 package or derivation should yield bit-identical results. Thus, through
3978 a diverse set of independent package builds, we can strengthen the
3979 integrity of our systems. The @command{guix challenge} command aims to
3980 help users assess substitute servers, and to assist developers in
3981 finding out about non-deterministic package builds (@pxref{Invoking guix
3982 challenge}). Similarly, the @option{--check} option of @command{guix
3983 build} allows users to check whether previously-installed substitutes
3984 are genuine by rebuilding them locally (@pxref{build-check,
3985 @command{guix build --check}}).
3987 In the future, we want Guix to have support to publish and retrieve
3988 binaries to/from other users, in a peer-to-peer fashion. If you would
3989 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3991 @node Packages with Multiple Outputs
3992 @section Packages with Multiple Outputs
3994 @cindex multiple-output packages
3995 @cindex package outputs
3998 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3999 source package leads to exactly one directory in the store. When running
4000 @command{guix install glibc}, one installs the default output of the
4001 GNU libc package; the default output is called @code{out}, but its name
4002 can be omitted as shown in this command. In this particular case, the
4003 default output of @code{glibc} contains all the C header files, shared
4004 libraries, static libraries, Info documentation, and other supporting
4007 Sometimes it is more appropriate to separate the various types of files
4008 produced from a single source package into separate outputs. For
4009 instance, the GLib C library (used by GTK+ and related packages)
4010 installs more than 20 MiB of reference documentation as HTML pages.
4011 To save space for users who do not need it, the documentation goes to a
4012 separate output, called @code{doc}. To install the main GLib output,
4013 which contains everything but the documentation, one would run:
4019 @cindex documentation
4020 The command to install its documentation is:
4023 guix install glib:doc
4026 Some packages install programs with different ``dependency footprints''.
4027 For instance, the WordNet package installs both command-line tools and
4028 graphical user interfaces (GUIs). The former depend solely on the C
4029 library, whereas the latter depend on Tcl/Tk and the underlying X
4030 libraries. In this case, we leave the command-line tools in the default
4031 output, whereas the GUIs are in a separate output. This allows users
4032 who do not need the GUIs to save space. The @command{guix size} command
4033 can help find out about such situations (@pxref{Invoking guix size}).
4034 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
4036 There are several such multiple-output packages in the GNU distribution.
4037 Other conventional output names include @code{lib} for libraries and
4038 possibly header files, @code{bin} for stand-alone programs, and
4039 @code{debug} for debugging information (@pxref{Installing Debugging
4040 Files}). The outputs of a packages are listed in the third column of
4041 the output of @command{guix package --list-available} (@pxref{Invoking
4045 @node Invoking guix gc
4046 @section Invoking @command{guix gc}
4048 @cindex garbage collector
4050 Packages that are installed, but not used, may be @dfn{garbage-collected}.
4051 The @command{guix gc} command allows users to explicitly run the garbage
4052 collector to reclaim space from the @file{/gnu/store} directory. It is
4053 the @emph{only} way to remove files from @file{/gnu/store}---removing
4054 files or directories manually may break it beyond repair!
4057 @cindex garbage collector roots
4058 The garbage collector has a set of known @dfn{roots}: any file under
4059 @file{/gnu/store} reachable from a root is considered @dfn{live} and
4060 cannot be deleted; any other file is considered @dfn{dead} and may be
4061 deleted. The set of garbage collector roots (``GC roots'' for short)
4062 includes default user profiles; by default, the symlinks under
4063 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
4064 added with @command{guix build --root}, for example (@pxref{Invoking
4065 guix build}). The @command{guix gc --list-roots} command lists them.
4067 Prior to running @code{guix gc --collect-garbage} to make space, it is
4068 often useful to remove old generations from user profiles; that way, old
4069 package builds referenced by those generations can be reclaimed. This
4070 is achieved by running @code{guix package --delete-generations}
4071 (@pxref{Invoking guix package}).
4073 Our recommendation is to run a garbage collection periodically, or when
4074 you are short on disk space. For instance, to guarantee that at least
4075 5@tie{}GB are available on your disk, simply run:
4081 It is perfectly safe to run as a non-interactive periodic job
4082 (@pxref{Scheduled Job Execution}, for how to set up such a job).
4083 Running @command{guix gc} with no arguments will collect as
4084 much garbage as it can, but that is often inconvenient: you may find
4085 yourself having to rebuild or re-download software that is ``dead'' from
4086 the GC viewpoint but that is necessary to build other pieces of
4087 software---e.g., the compiler tool chain.
4089 The @command{guix gc} command has three modes of operation: it can be
4090 used to garbage-collect any dead files (the default), to delete specific
4091 files (the @option{--delete} option), to print garbage-collector
4092 information, or for more advanced queries. The garbage collection
4093 options are as follows:
4096 @item --collect-garbage[=@var{min}]
4097 @itemx -C [@var{min}]
4098 Collect garbage---i.e., unreachable @file{/gnu/store} files and
4099 sub-directories. This is the default operation when no option is
4102 When @var{min} is given, stop once @var{min} bytes have been collected.
4103 @var{min} may be a number of bytes, or it may include a unit as a
4104 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
4105 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
4107 When @var{min} is omitted, collect all the garbage.
4109 @item --free-space=@var{free}
4110 @itemx -F @var{free}
4111 Collect garbage until @var{free} space is available under
4112 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
4113 as @code{500MiB}, as described above.
4115 When @var{free} or more is already available in @file{/gnu/store}, do
4116 nothing and exit immediately.
4118 @item --delete-generations[=@var{duration}]
4119 @itemx -d [@var{duration}]
4120 Before starting the garbage collection process, delete all the generations
4121 older than @var{duration}, for all the user profiles; when run as root, this
4122 applies to all the profiles @emph{of all the users}.
4124 For example, this command deletes all the generations of all your profiles
4125 that are older than 2 months (except generations that are current), and then
4126 proceeds to free space until at least 10 GiB are available:
4129 guix gc -d 2m -F 10G
4134 Attempt to delete all the store files and directories specified as
4135 arguments. This fails if some of the files are not in the store, or if
4136 they are still live.
4138 @item --list-failures
4139 List store items corresponding to cached build failures.
4141 This prints nothing unless the daemon was started with
4142 @option{--cache-failures} (@pxref{Invoking guix-daemon,
4143 @option{--cache-failures}}).
4146 List the GC roots owned by the user; when run as root, list @emph{all} the GC
4150 List store items in use by currently running processes. These store
4151 items are effectively considered GC roots: they cannot be deleted.
4153 @item --clear-failures
4154 Remove the specified store items from the failed-build cache.
4156 Again, this option only makes sense when the daemon is started with
4157 @option{--cache-failures}. Otherwise, it does nothing.
4160 Show the list of dead files and directories still present in the
4161 store---i.e., files and directories no longer reachable from any root.
4164 Show the list of live store files and directories.
4168 In addition, the references among existing store files can be queried:
4174 @cindex package dependencies
4175 List the references (respectively, the referrers) of store files given
4181 List the requisites of the store files passed as arguments. Requisites
4182 include the store files themselves, their references, and the references
4183 of these, recursively. In other words, the returned list is the
4184 @dfn{transitive closure} of the store files.
4186 @xref{Invoking guix size}, for a tool to profile the size of the closure
4187 of an element. @xref{Invoking guix graph}, for a tool to visualize
4188 the graph of references.
4192 Return the derivation(s) leading to the given store items
4193 (@pxref{Derivations}).
4195 For example, this command:
4198 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
4202 returns the @file{.drv} file(s) leading to the @code{emacs} package
4203 installed in your profile.
4205 Note that there may be zero matching @file{.drv} files, for instance
4206 because these files have been garbage-collected. There can also be more
4207 than one matching @file{.drv} due to fixed-output derivations.
4210 Lastly, the following options allow you to check the integrity of the
4211 store and to control disk usage.
4215 @item --verify[=@var{options}]
4216 @cindex integrity, of the store
4217 @cindex integrity checking
4218 Verify the integrity of the store.
4220 By default, make sure that all the store items marked as valid in the
4221 database of the daemon actually exist in @file{/gnu/store}.
4223 When provided, @var{options} must be a comma-separated list containing one
4224 or more of @code{contents} and @code{repair}.
4226 When passing @option{--verify=contents}, the daemon computes the
4227 content hash of each store item and compares it against its hash in the
4228 database. Hash mismatches are reported as data corruptions. Because it
4229 traverses @emph{all the files in the store}, this command can take a
4230 long time, especially on systems with a slow disk drive.
4232 @cindex repairing the store
4233 @cindex corruption, recovering from
4234 Using @option{--verify=repair} or @option{--verify=contents,repair}
4235 causes the daemon to try to repair corrupt store items by fetching
4236 substitutes for them (@pxref{Substitutes}). Because repairing is not
4237 atomic, and thus potentially dangerous, it is available only to the
4238 system administrator. A lightweight alternative, when you know exactly
4239 which items in the store are corrupt, is @command{guix build --repair}
4240 (@pxref{Invoking guix build}).
4243 @cindex deduplication
4244 Optimize the store by hard-linking identical files---this is
4245 @dfn{deduplication}.
4247 The daemon performs deduplication after each successful build or archive
4248 import, unless it was started with @option{--disable-deduplication}
4249 (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
4250 this option is primarily useful when the daemon was running with
4251 @option{--disable-deduplication}.
4255 @node Invoking guix pull
4256 @section Invoking @command{guix pull}
4258 @cindex upgrading Guix
4259 @cindex updating Guix
4260 @cindex @command{guix pull}
4262 @cindex security, @command{guix pull}
4263 @cindex authenticity, of code obtained with @command{guix pull}
4264 Packages are installed or upgraded to the latest version available in
4265 the distribution currently available on your local machine. To update
4266 that distribution, along with the Guix tools, you must run @command{guix
4267 pull}: the command downloads the latest Guix source code and package
4268 descriptions, and deploys it. Source code is downloaded from a
4269 @uref{https://git-scm.com, Git} repository, by default the official
4270 GNU@tie{}Guix repository, though this can be customized. @command{guix
4271 pull} ensures that the code it downloads is @emph{authentic} by
4272 verifying that commits are signed by Guix developers.
4274 Specifically, @command{guix pull} downloads code from the @dfn{channels}
4275 (@pxref{Channels}) specified by one of the followings, in this order:
4279 the @option{--channels} option;
4281 the user's @file{~/.config/guix/channels.scm} file;
4283 the system-wide @file{/etc/guix/channels.scm} file;
4285 the built-in default channels specified in the @code{%default-channels}
4289 On completion, @command{guix package} will use packages and package
4290 versions from this just-retrieved copy of Guix. Not only that, but all
4291 the Guix commands and Scheme modules will also be taken from that latest
4292 version. New @command{guix} sub-commands added by the update also
4295 Any user can update their Guix copy using @command{guix pull}, and the
4296 effect is limited to the user who ran @command{guix pull}. For
4297 instance, when user @code{root} runs @command{guix pull}, this has no
4298 effect on the version of Guix that user @code{alice} sees, and vice
4301 The result of running @command{guix pull} is a @dfn{profile} available
4302 under @file{~/.config/guix/current} containing the latest Guix. Thus,
4303 make sure to add it to the beginning of your search path so that you use
4304 the latest version, and similarly for the Info manual
4305 (@pxref{Documentation}):
4308 export PATH="$HOME/.config/guix/current/bin:$PATH"
4309 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
4312 The @option{--list-generations} or @option{-l} option lists past generations
4313 produced by @command{guix pull}, along with details about their provenance:
4317 Generation 1 Jun 10 2018 00:18:18
4319 repository URL: https://git.savannah.gnu.org/git/guix.git
4320 branch: origin/master
4321 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
4323 Generation 2 Jun 11 2018 11:02:49
4325 repository URL: https://git.savannah.gnu.org/git/guix.git
4326 branch: origin/master
4327 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
4328 2 new packages: keepalived, libnfnetlink
4329 6 packages upgraded: emacs-nix-mode@@2.0.4,
4330 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
4331 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
4333 Generation 3 Jun 13 2018 23:31:07 (current)
4335 repository URL: https://git.savannah.gnu.org/git/guix.git
4336 branch: origin/master
4337 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
4338 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
4339 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
4342 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
4343 describe the current status of Guix.
4345 This @code{~/.config/guix/current} profile works exactly like the profiles
4346 created by @command{guix package} (@pxref{Invoking guix package}). That
4347 is, you can list generations, roll back to the previous
4348 generation---i.e., the previous Guix---and so on:
4351 $ guix pull --roll-back
4352 switched from generation 3 to 2
4353 $ guix pull --delete-generations=1
4354 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4357 You can also use @command{guix package} (@pxref{Invoking guix package})
4358 to manage the profile by naming it explicitly:
4360 $ guix package -p ~/.config/guix/current --roll-back
4361 switched from generation 3 to 2
4362 $ guix package -p ~/.config/guix/current --delete-generations=1
4363 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4366 The @command{guix pull} command is usually invoked with no arguments,
4367 but it supports the following options:
4370 @item --url=@var{url}
4371 @itemx --commit=@var{commit}
4372 @itemx --branch=@var{branch}
4373 Download code for the @code{guix} channel from the specified @var{url}, at the
4374 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4375 string), or @var{branch}.
4377 @cindex @file{channels.scm}, configuration file
4378 @cindex configuration file for channels
4379 These options are provided for convenience, but you can also specify your
4380 configuration in the @file{~/.config/guix/channels.scm} file or using the
4381 @option{--channels} option (see below).
4383 @item --channels=@var{file}
4384 @itemx -C @var{file}
4385 Read the list of channels from @var{file} instead of
4386 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
4387 @var{file} must contain Scheme code that
4388 evaluates to a list of channel objects. @xref{Channels}, for more
4391 @cindex channel news
4394 Display the list of packages added or upgraded since the previous
4395 generation, as well as, occasionally, news written by channel authors
4396 for their users (@pxref{Channels, Writing Channel News}).
4398 The package information is the same as displayed upon @command{guix
4399 pull} completion, but without ellipses; it is also similar to the output
4400 of @command{guix pull -l} for the last generation (see below).
4402 @item --list-generations[=@var{pattern}]
4403 @itemx -l [@var{pattern}]
4404 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
4405 is provided, the subset of generations that match @var{pattern}.
4406 The syntax of @var{pattern} is the same as with @code{guix package
4407 --list-generations} (@pxref{Invoking guix package}).
4410 @cindex rolling back
4411 @cindex undoing transactions
4412 @cindex transactions, undoing
4413 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
4414 undo the last transaction.
4416 @item --switch-generation=@var{pattern}
4417 @itemx -S @var{pattern}
4419 Switch to a particular generation defined by @var{pattern}.
4421 @var{pattern} may be either a generation number or a number prefixed
4422 with ``+'' or ``-''. The latter means: move forward/backward by a
4423 specified number of generations. For example, if you want to return to
4424 the latest generation after @option{--roll-back}, use
4425 @option{--switch-generation=+1}.
4427 @item --delete-generations[=@var{pattern}]
4428 @itemx -d [@var{pattern}]
4429 When @var{pattern} is omitted, delete all generations except the current
4432 This command accepts the same patterns as @option{--list-generations}.
4433 When @var{pattern} is specified, delete the matching generations. When
4434 @var{pattern} specifies a duration, generations @emph{older} than the
4435 specified duration match. For instance, @option{--delete-generations=1m}
4436 deletes generations that are more than one month old.
4438 If the current generation matches, it is @emph{not} deleted.
4440 Note that deleting generations prevents rolling back to them.
4441 Consequently, this command must be used with care.
4443 @xref{Invoking guix describe}, for a way to display information about the
4444 current generation only.
4446 @item --profile=@var{profile}
4447 @itemx -p @var{profile}
4448 Use @var{profile} instead of @file{~/.config/guix/current}.
4452 Show which channel commit(s) would be used and what would be built or
4453 substituted but do not actually do it.
4455 @item --allow-downgrades
4456 Allow pulling older or unrelated revisions of channels than those
4459 @cindex downgrade attacks, protection against
4460 By default, @command{guix pull} protects against so-called ``downgrade
4461 attacks'' whereby the Git repository of a channel would be reset to an
4462 earlier or unrelated revision of itself, potentially leading you to
4463 install older, known-vulnerable versions of software packages.
4466 Make sure you understand its security implications before using
4467 @option{--allow-downgrades}.
4470 @item --disable-authentication
4471 Allow pulling channel code without authenticating it.
4473 @cindex authentication, of channel code
4474 By default, @command{guix pull} authenticates code downloaded from
4475 channels by verifying that its commits are signed by authorized
4476 developers, and raises an error if this is not the case. This option
4477 instructs it to not perform any such verification.
4480 Make sure you understand its security implications before using
4481 @option{--disable-authentication}.
4484 @item --system=@var{system}
4485 @itemx -s @var{system}
4486 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4487 the system type of the build host.
4490 Use the bootstrap Guile to build the latest Guix. This option is only
4491 useful to Guix developers.
4494 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
4495 repository and branch to pull from, as well as @emph{additional} repositories
4496 containing package modules that should be deployed. @xref{Channels}, for more
4499 In addition, @command{guix pull} supports all the common build options
4500 (@pxref{Common Build Options}).
4502 @node Invoking guix time-machine
4503 @section Invoking @command{guix time-machine}
4505 @cindex @command{guix time-machine}
4506 @cindex pinning, channels
4507 @cindex replicating Guix
4508 @cindex reproducibility, of Guix
4510 The @command{guix time-machine} command provides access to other
4511 revisions of Guix, for example to install older versions of packages,
4512 or to reproduce a computation in an identical environment. The revision
4513 of Guix to be used is defined by a commit or by a channel
4514 description file created by @command{guix describe}
4515 (@pxref{Invoking guix describe}).
4517 The general syntax is:
4520 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4523 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4524 @command{guix} command of the specified revision. The @var{options} that define
4525 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4528 @item --url=@var{url}
4529 @itemx --commit=@var{commit}
4530 @itemx --branch=@var{branch}
4531 Use the @code{guix} channel from the specified @var{url}, at the
4532 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4533 string), or @var{branch}.
4535 @item --channels=@var{file}
4536 @itemx -C @var{file}
4537 Read the list of channels from @var{file}. @var{file} must contain
4538 Scheme code that evaluates to a list of channel objects.
4539 @xref{Channels} for more information.
4542 As for @command{guix pull}, the absence of any options means that the
4543 latest commit on the master branch will be used. The command
4546 guix time-machine -- build hello
4549 will thus build the package @code{hello} as defined in the master branch,
4550 which is in general a newer revision of Guix than you have installed.
4551 Time travel works in both directions!
4553 Note that @command{guix time-machine} can trigger builds of channels and
4554 their dependencies, and these are controlled by the standard build
4555 options (@pxref{Common Build Options}).
4560 @c TODO: Remove this once we're more confident about API stability.
4562 The functionality described here is a ``technology preview'' as of version
4563 @value{VERSION}. As such, the interface is subject to change.
4567 @cindex composition of Guix revisions
4568 Sometimes you might need to mix packages from the revision of Guix you're
4569 currently running with packages available in a different revision of Guix.
4570 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4571 revisions in arbitrary ways.
4573 @cindex inferior packages
4574 Technically, an ``inferior'' is essentially a separate Guix process connected
4575 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4576 @code{(guix inferior)} module allows you to create inferiors and to
4577 communicate with them. It also provides a high-level interface to browse and
4578 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4580 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4581 to interact with a separate revision of Guix. For example, let's assume you
4582 want to install in your profile the current @code{guile} package, along with
4583 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4584 because the newer @code{guile-json} has an incompatible API and you want to
4585 run your code against the old API@. To do that, you could write a manifest for
4586 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4587 manifest, you would create an inferior for that old Guix revision you care
4588 about, and you would look up the @code{guile-json} package in the inferior:
4591 (use-modules (guix inferior) (guix channels)
4592 (srfi srfi-1)) ;for 'first'
4595 ;; This is the old revision from which we want to
4596 ;; extract guile-json.
4599 (url "https://git.savannah.gnu.org/git/guix.git")
4601 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4604 ;; An inferior representing the above revision.
4605 (inferior-for-channels channels))
4607 ;; Now create a manifest with the current "guile" package
4608 ;; and the old "guile-json" package.
4610 (list (first (lookup-inferior-packages inferior "guile-json"))
4611 (specification->package "guile")))
4614 On its first run, @command{guix package --manifest} might have to build the
4615 channel you specified before it can create the inferior; subsequent runs will
4616 be much faster because the Guix revision will be cached.
4618 The @code{(guix inferior)} module provides the following procedures to open an
4621 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4622 [#:cache-directory] [#:ttl]
4623 Return an inferior for @var{channels}, a list of channels. Use the cache at
4624 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4625 This procedure opens a new connection to the build daemon.
4627 As a side effect, this procedure may build or substitute binaries for
4628 @var{channels}, which can take time.
4631 @deffn {Scheme Procedure} open-inferior @var{directory} @
4632 [#:command "bin/guix"]
4633 Open the inferior Guix in @var{directory}, running
4634 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4635 the inferior could not be launched.
4638 @cindex inferior packages
4639 The procedures listed below allow you to obtain and manipulate inferior
4642 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4643 Return the list of packages known to @var{inferior}.
4646 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4648 Return the sorted list of inferior packages matching @var{name} in
4649 @var{inferior}, with highest version numbers first. If @var{version} is true,
4650 return only packages with a version number prefixed by @var{version}.
4653 @deffn {Scheme Procedure} inferior-package? @var{obj}
4654 Return true if @var{obj} is an inferior package.
4657 @deffn {Scheme Procedure} inferior-package-name @var{package}
4658 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4659 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4660 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4661 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4662 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4663 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4664 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4665 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4666 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4667 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4668 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4669 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4670 These procedures are the counterpart of package record accessors
4671 (@pxref{package Reference}). Most of them work by querying the inferior
4672 @var{package} comes from, so the inferior must still be live when you call
4676 Inferior packages can be used transparently like any other package or
4677 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4678 transparently handled by the @code{packages->manifest} procedure, which is
4679 commonly use in manifests (@pxref{Invoking guix package, the
4680 @option{--manifest} option of @command{guix package}}). Thus you can insert
4681 an inferior package pretty much anywhere you would insert a regular package:
4682 in manifests, in the @code{packages} field of your @code{operating-system}
4683 declaration, and so on.
4685 @node Invoking guix describe
4686 @section Invoking @command{guix describe}
4688 @cindex reproducibility
4689 @cindex replicating Guix
4690 Often you may want to answer questions like: ``Which revision of Guix am I
4691 using?'' or ``Which channels am I using?'' This is useful information in many
4692 situations: if you want to @emph{replicate} an environment on a different
4693 machine or user account, if you want to report a bug or to determine what
4694 change in the channels you are using caused it, or if you want to record your
4695 system state for reproducibility purposes. The @command{guix describe}
4696 command answers these questions.
4698 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4699 displays the channel(s) that it was built from, including their repository URL
4700 and commit IDs (@pxref{Channels}):
4704 Generation 10 Sep 03 2018 17:32:44 (current)
4706 repository URL: https://git.savannah.gnu.org/git/guix.git
4708 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4711 If you're familiar with the Git version control system, this is similar in
4712 spirit to @command{git describe}; the output is also similar to that of
4713 @command{guix pull --list-generations}, but limited to the current generation
4714 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4715 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4716 information is all it takes to describe the revision of Guix you're using, and
4717 also to replicate it.
4719 To make it easier to replicate Guix, @command{guix describe} can also be asked
4720 to return a list of channels instead of the human-readable description above:
4723 $ guix describe -f channels
4726 (url "https://git.savannah.gnu.org/git/guix.git")
4728 "e0fa68c7718fffd33d81af415279d6ddb518f727")
4730 (make-channel-introduction
4731 "9edb3f66fd807b096b48283debdcddccfea34bad"
4732 (openpgp-fingerprint
4733 "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
4737 You can save this to a file and feed it to @command{guix pull -C} on some
4738 other machine or at a later point in time, which will instantiate @emph{this
4739 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4740 From there on, since you're able to deploy the same revision of Guix, you can
4741 just as well @emph{replicate a complete software environment}. We humbly
4742 think that this is @emph{awesome}, and we hope you'll like it too!
4744 The details of the options supported by @command{guix describe} are as
4748 @item --format=@var{format}
4749 @itemx -f @var{format}
4750 Produce output in the specified @var{format}, one of:
4754 produce human-readable output;
4756 produce a list of channel specifications that can be passed to @command{guix
4757 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4759 @item channels-sans-intro
4760 like @code{channels}, but omit the @code{introduction} field; use it to
4761 produce a channel specification suitable for Guix version 1.1.0 or
4762 earlier---the @code{introduction} field has to do with channel
4763 authentication (@pxref{Channels, Channel Authentication}) and is not
4764 supported by these older versions;
4767 produce a list of channel specifications in JSON format;
4769 produce a list of channel specifications in Recutils format.
4772 @item --list-formats
4773 Display available formats for @option{--format} option.
4775 @item --profile=@var{profile}
4776 @itemx -p @var{profile}
4777 Display information about @var{profile}.
4780 @node Invoking guix archive
4781 @section Invoking @command{guix archive}
4783 @cindex @command{guix archive}
4785 The @command{guix archive} command allows users to @dfn{export} files
4786 from the store into a single archive, and to later @dfn{import} them on
4787 a machine that runs Guix.
4788 In particular, it allows store files to be transferred from one machine
4789 to the store on another machine.
4792 If you're looking for a way to produce archives in a format suitable for
4793 tools other than Guix, @pxref{Invoking guix pack}.
4796 @cindex exporting store items
4797 To export store files as an archive to standard output, run:
4800 guix archive --export @var{options} @var{specifications}...
4803 @var{specifications} may be either store file names or package
4804 specifications, as for @command{guix package} (@pxref{Invoking guix
4805 package}). For instance, the following command creates an archive
4806 containing the @code{gui} output of the @code{git} package and the main
4807 output of @code{emacs}:
4810 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4813 If the specified packages are not built yet, @command{guix archive}
4814 automatically builds them. The build process may be controlled with the
4815 common build options (@pxref{Common Build Options}).
4817 To transfer the @code{emacs} package to a machine connected over SSH,
4821 guix archive --export -r emacs | ssh the-machine guix archive --import
4825 Similarly, a complete user profile may be transferred from one machine
4826 to another like this:
4829 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4830 ssh the-machine guix archive --import
4834 However, note that, in both examples, all of @code{emacs} and the
4835 profile as well as all of their dependencies are transferred (due to
4836 @option{-r}), regardless of what is already available in the store on
4837 the target machine. The @option{--missing} option can help figure out
4838 which items are missing from the target store. The @command{guix copy}
4839 command simplifies and optimizes this whole process, so this is probably
4840 what you should use in this case (@pxref{Invoking guix copy}).
4842 @cindex nar, archive format
4843 @cindex normalized archive (nar)
4844 @cindex nar bundle, archive format
4845 Each store item is written in the @dfn{normalized archive} or @dfn{nar}
4846 format (described below), and the output of @command{guix archive
4847 --export} (and input of @command{guix archive --import}) is a @dfn{nar
4851 comparable in spirit to `tar', but with differences
4852 that make it more appropriate for our purposes. First, rather than
4853 recording all Unix metadata for each file, the nar format only mentions
4854 the file type (regular, directory, or symbolic link); Unix permissions
4855 and owner/group are dismissed. Second, the order in which directory
4856 entries are stored always follows the order of file names according to
4857 the C locale collation order. This makes archive production fully
4860 That nar bundle format is essentially the concatenation of zero or more
4861 nars along with metadata for each store item it contains: its file name,
4862 references, corresponding derivation, and a digital signature.
4864 When exporting, the daemon digitally signs the contents of the archive,
4865 and that digital signature is appended. When importing, the daemon
4866 verifies the signature and rejects the import in case of an invalid
4867 signature or if the signing key is not authorized.
4868 @c FIXME: Add xref to daemon doc about signatures.
4870 The main options are:
4874 Export the specified store files or packages (see below). Write the
4875 resulting archive to the standard output.
4877 Dependencies are @emph{not} included in the output, unless
4878 @option{--recursive} is passed.
4882 When combined with @option{--export}, this instructs @command{guix archive}
4883 to include dependencies of the given items in the archive. Thus, the
4884 resulting archive is self-contained: it contains the closure of the
4885 exported store items.
4888 Read an archive from the standard input, and import the files listed
4889 therein into the store. Abort if the archive has an invalid digital
4890 signature, or if it is signed by a public key not among the authorized
4891 keys (see @option{--authorize} below).
4894 Read a list of store file names from the standard input, one per line,
4895 and write on the standard output the subset of these files missing from
4898 @item --generate-key[=@var{parameters}]
4899 @cindex signing, archives
4900 Generate a new key pair for the daemon. This is a prerequisite before
4901 archives can be exported with @option{--export}. This
4902 operation is usually instantaneous but it can take time if the system's
4903 entropy pool needs to be refilled. On Guix System,
4904 @code{guix-service-type} takes care of generating this key pair the
4907 The generated key pair is typically stored under @file{/etc/guix}, in
4908 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4909 key, which must be kept secret). When @var{parameters} is omitted,
4910 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4911 versions before 1.6.0, it is a 4096-bit RSA key.
4912 Alternatively, @var{parameters} can specify
4913 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4914 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4915 Libgcrypt Reference Manual}).
4918 @cindex authorizing, archives
4919 Authorize imports signed by the public key passed on standard input.
4920 The public key must be in ``s-expression advanced format''---i.e., the
4921 same format as the @file{signing-key.pub} file.
4923 The list of authorized keys is kept in the human-editable file
4924 @file{/etc/guix/acl}. The file contains
4925 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4926 s-expressions''} and is structured as an access-control list in the
4927 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4930 @item --extract=@var{directory}
4931 @itemx -x @var{directory}
4932 Read a single-item archive as served by substitute servers
4933 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4934 low-level operation needed in only very narrow use cases; see below.
4936 For example, the following command extracts the substitute for Emacs
4937 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4941 https://@value{SUBSTITUTE-SERVER}/nar/gzip/@dots{}-emacs-24.5 \
4942 | gunzip | guix archive -x /tmp/emacs
4945 Single-item archives are different from multiple-item archives produced
4946 by @command{guix archive --export}; they contain a single store item,
4947 and they do @emph{not} embed a signature. Thus this operation does
4948 @emph{no} signature verification and its output should be considered
4951 The primary purpose of this operation is to facilitate inspection of
4952 archive contents coming from possibly untrusted substitute servers
4953 (@pxref{Invoking guix challenge}).
4957 Read a single-item archive as served by substitute servers
4958 (@pxref{Substitutes}) and print the list of files it contains, as in
4963 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4964 | lzip -d | guix archive -t
4969 @c *********************************************************************
4974 @cindex @file{channels.scm}, configuration file
4975 @cindex configuration file for channels
4976 @cindex @command{guix pull}, configuration file
4977 @cindex configuration of @command{guix pull}
4978 Guix and its package collection are updated by running @command{guix pull}
4979 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
4980 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
4981 customized by defining @dfn{channels} in the
4982 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
4983 of a Git repository to be deployed, and @command{guix pull} can be instructed
4984 to pull from one or more channels. In other words, channels can be used
4985 to @emph{customize} and to @emph{extend} Guix, as we will see below.
4986 Guix is able to take into account security concerns and deal with authenticated
4990 * Specifying Additional Channels:: Extending the package collection.
4991 * Using a Custom Guix Channel:: Using a customized Guix.
4992 * Replicating Guix:: Running the @emph{exact same} Guix.
4993 * Channel Authentication:: How Guix verifies what it fetches.
4994 * Creating a Channel:: How to write your custom channel.
4995 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
4996 * Declaring Channel Dependencies:: How to depend on other channels.
4997 * Specifying Channel Authorizations:: Defining channel authors authorizations.
4998 * Primary URL:: Distinguishing mirror to original.
4999 * Writing Channel News:: Communicating information to channel's users.
5000 * Channels with Substitutes:: Using channels with available substitutes.
5003 @node Specifying Additional Channels
5004 @section Specifying Additional Channels
5006 @cindex extending the package collection (channels)
5007 @cindex variant packages (channels)
5008 You can specify @emph{additional channels} to pull from. To use a channel, write
5009 @code{~/.config/guix/channels.scm} to instruct @command{guix pull} to pull from it
5010 @emph{in addition} to the default Guix channel(s):
5012 @vindex %default-channels
5014 ;; Add variant packages to those Guix provides.
5016 (name 'variant-packages)
5017 (url "https://example.org/variant-packages.git"))
5022 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
5023 add a channel the list of channels that the variable @code{%default-channels}
5024 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
5025 Manual}). With this file in place, @command{guix pull} builds not only Guix
5026 but also the package modules from your own repository. The result in
5027 @file{~/.config/guix/current} is the union of Guix with your own package
5031 $ guix pull --list-generations
5033 Generation 19 Aug 27 2018 16:20:48
5035 repository URL: https://git.savannah.gnu.org/git/guix.git
5037 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
5038 variant-packages dd3df5e
5039 repository URL: https://example.org/variant-packages.git
5041 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
5042 11 new packages: variant-gimp, variant-emacs-with-cool-features, @dots{}
5043 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
5047 The output of @command{guix pull} above shows that Generation@tie{}19 includes
5048 both Guix and packages from the @code{variant-personal-packages} channel. Among
5049 the new and upgraded packages that are listed, some like @code{variant-gimp} and
5050 @code{variant-emacs-with-cool-features} might come from
5051 @code{variant-packages}, while others come from the Guix default channel.
5053 @node Using a Custom Guix Channel
5054 @section Using a Custom Guix Channel
5056 The channel called @code{guix} specifies where Guix itself---its command-line
5057 tools as well as its package collection---should be downloaded. For instance,
5058 suppose you want to update from another copy of the Guix repository at
5059 @code{example.org}, and specifically the @code{super-hacks} branch, you can
5060 write in @code{~/.config/guix/channels.scm} this specification:
5063 ;; Tell 'guix pull' to use another repo.
5066 (url "https://example.org/another-guix.git")
5067 (branch "super-hacks")))
5071 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
5072 branch of the repository at @code{example.org}. The authentication concern is
5073 addressed below ((@pxref{Channel Authentication}).
5075 @node Replicating Guix
5076 @section Replicating Guix
5078 @cindex pinning, channels
5079 @cindex replicating Guix
5080 @cindex reproducibility, of Guix
5081 The @command{guix pull --list-generations} output above shows precisely which
5082 commits were used to build this instance of Guix. We can thus replicate it,
5083 say, on another machine, by providing a channel specification in
5084 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
5087 ;; Deploy specific commits of my channels of interest.
5090 (url "https://git.savannah.gnu.org/git/guix.git")
5091 (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
5093 (name 'variant-packages)
5094 (url "https://example.org/variant-packages.git")
5095 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
5098 The @command{guix describe --format=channels} command can even generate this
5099 list of channels directly (@pxref{Invoking guix describe}). The resulting
5100 file can be used with the -C options of @command{guix pull}
5101 (@pxref{Invoking guix pull}) or @command{guix time-machine}
5102 (@pxref{Invoking guix time-machine}).
5104 At this point the two machines run the @emph{exact same Guix}, with access to
5105 the @emph{exact same packages}. The output of @command{guix build gimp} on
5106 one machine will be exactly the same, bit for bit, as the output of the same
5107 command on the other machine. It also means both machines have access to all
5108 the source code of Guix and, transitively, to all the source code of every
5111 This gives you super powers, allowing you to track the provenance of binary
5112 artifacts with very fine grain, and to reproduce software environments at
5113 will---some sort of ``meta reproducibility'' capabilities, if you will.
5114 @xref{Inferiors}, for another way to take advantage of these super powers.
5116 @node Channel Authentication
5117 @section Channel Authentication
5119 @anchor{channel-authentication}
5120 @cindex authentication, of channel code
5121 The @command{guix pull} and @command{guix time-machine} commands
5122 @dfn{authenticate} the code retrieved from channels: they make sure each
5123 commit that is fetched is signed by an authorized developer. The goal
5124 is to protect from unauthorized modifications to the channel that would
5125 lead users to run malicious code.
5127 As a user, you must provide a @dfn{channel introduction} in your
5128 channels file so that Guix knows how to authenticate its first commit.
5129 A channel specification, including its introduction, looks something
5134 (name 'some-channel)
5135 (url "https://example.org/some-channel.git")
5137 (make-channel-introduction
5138 "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
5139 (openpgp-fingerprint
5140 "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5143 The specification above shows the name and URL of the channel. The call
5144 to @code{make-channel-introduction} above specifies that authentication
5145 of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
5146 by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
5148 For the main channel, called @code{guix}, you automatically get that
5149 information from your Guix installation. For other channels, include
5150 the channel introduction provided by the channel authors in your
5151 @file{channels.scm} file. Make sure you retrieve the channel
5152 introduction from a trusted source since that is the root of your trust.
5154 If you're curious about the authentication mechanics, read on!
5156 @node Creating a Channel
5157 @section Creating a Channel
5159 @cindex personal packages (channels)
5160 @cindex channels, for personal packages
5161 Let's say you have a bunch of custom package variants or personal packages
5162 that you think would make little sense to contribute to the Guix project, but
5163 would like to have these packages transparently available to you at the
5164 command line. You would first write modules containing those package
5165 definitions (@pxref{Package Modules}), maintain them in a Git repository, and
5166 then you and anyone else can use it as an additional channel to get packages
5169 @c What follows stems from discussions at
5170 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
5171 @c earlier discussions on guix-devel@gnu.org.
5173 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
5174 publish your personal channel to the world, we would like to share a few words
5179 Before publishing a channel, please consider contributing your package
5180 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
5181 to free software of all sorts, and packages in Guix proper are readily
5182 available to all Guix users and benefit from the project's quality assurance
5186 When you maintain package definitions outside Guix, we, Guix developers,
5187 consider that @emph{the compatibility burden is on you}. Remember that
5188 package modules and package definitions are just Scheme code that uses various
5189 programming interfaces (APIs). We want to remain free to change these APIs to
5190 keep improving Guix, possibly in ways that break your channel. We never
5191 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
5195 Corollary: if you're using an external channel and that channel breaks, please
5196 @emph{report the issue to the channel authors}, not to the Guix project.
5199 You've been warned! Having said this, we believe external channels are a
5200 practical way to exert your freedom to augment Guix' package collection and to
5201 share your improvements, which are basic tenets of
5202 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
5203 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
5206 To create a channel, create a Git repository containing your own package
5207 modules and make it available. The repository can contain anything, but a
5208 useful channel will contain Guile modules that export packages. Once you
5209 start using a channel, Guix will behave as if the root directory of that
5210 channel's Git repository has been added to the Guile load path (@pxref{Load
5211 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
5212 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
5213 module, then the module will be available under the name @code{(my-packages
5214 my-tools)}, and you will be able to use it like any other module
5215 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
5217 As a channel author, consider bundling authentication material with your
5218 channel so that users can authenticate it. @xref{Channel
5219 Authentication}, and @ref{Specifying Channel Authorizations}, for info
5223 @node Package Modules in a Sub-directory
5224 @section Package Modules in a Sub-directory
5226 @cindex subdirectory, channels
5227 As a channel author, you may want to keep your channel modules in a
5228 sub-directory. If your modules are in the sub-directory @file{guix}, you must
5229 add a meta-data file @file{.guix-channel} that contains:
5237 @node Declaring Channel Dependencies
5238 @section Declaring Channel Dependencies
5240 @cindex dependencies, channels
5241 @cindex meta-data, channels
5242 Channel authors may decide to augment a package collection provided by other
5243 channels. They can declare their channel to be dependent on other channels in
5244 a meta-data file @file{.guix-channel}, which is to be placed in the root of
5245 the channel repository.
5247 The meta-data file should contain a simple S-expression like this:
5254 (name 'some-collection)
5255 (url "https://example.org/first-collection.git")
5257 ;; The 'introduction' bit below is optional: you would
5258 ;; provide it for dependencies that can be authenticated.
5260 (channel-introduction
5262 (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
5263 (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5265 (name 'some-other-collection)
5266 (url "https://example.org/second-collection.git")
5267 (branch "testing"))))
5270 In the above example this channel is declared to depend on two other channels,
5271 which will both be fetched automatically. The modules provided by the channel
5272 will be compiled in an environment where the modules of all these declared
5273 channels are available.
5275 For the sake of reliability and maintainability, you should avoid dependencies
5276 on channels that you don't control, and you should aim to keep the number of
5277 dependencies to a minimum.
5279 @node Specifying Channel Authorizations
5280 @section Specifying Channel Authorizations
5282 @cindex channel authorizations
5283 @anchor{channel-authorizations}
5284 As we saw above, Guix ensures the source code it pulls from channels
5285 comes from authorized developers. As a channel author, you need to
5286 specify the list of authorized developers in the
5287 @file{.guix-authorizations} file in the channel's Git repository. The
5288 authentication rule is simple: each commit must be signed by a key
5289 listed in the @file{.guix-authorizations} file of its parent
5290 commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
5291 (DAG). Each commit can have zero or more parents; ``regular'' commits
5292 have one parent and merge commits have two parent commits. Read
5293 @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
5294 for Computer Scientists}} for a great overview.} The
5295 @file{.guix-authorizations} file looks like this:
5298 ;; Example '.guix-authorizations' file.
5301 (version 0) ;current file format version
5303 (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
5305 ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
5307 ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
5311 Each fingerprint is followed by optional key/value pairs, as in the
5312 example above. Currently these key/value pairs are ignored.
5314 This authentication rule creates a chicken-and-egg issue: how do we
5315 authenticate the first commit? Related to that: how do we deal with
5316 channels whose repository history contains unsigned commits and lack
5317 @file{.guix-authorizations}? And how do we fork existing channels?
5319 @cindex channel introduction
5320 Channel introductions answer these questions by describing the first
5321 commit of a channel that should be authenticated. The first time a
5322 channel is fetched with @command{guix pull} or @command{guix
5323 time-machine}, the command looks up the introductory commit and verifies
5324 that it is signed by the specified OpenPGP key. From then on, it
5325 authenticates commits according to the rule above.
5327 Additionally, your channel must provide all the OpenPGP keys that were
5328 ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
5329 files, which can be either binary or ``ASCII-armored''. By default,
5330 those @file{.key} files are searched for in the branch named
5331 @code{keyring} but you can specify a different branch name in
5332 @code{.guix-channel} like so:
5337 (keyring-reference "my-keyring-branch"))
5340 To summarize, as the author of a channel, there are three things you have
5341 to do to allow users to authenticate your code:
5345 Export the OpenPGP keys of past and present committers with @command{gpg
5346 --export} and store them in @file{.key} files, by default in a branch
5347 named @code{keyring} (we recommend making it an @dfn{orphan branch}).
5350 Introduce an initial @file{.guix-authorizations} in the channel's
5351 repository. Do that in a signed commit (@pxref{Commit Access}, for
5352 information on how to sign Git commits.)
5355 Advertise the channel introduction, for instance on your channel's web
5356 page. The channel introduction, as we saw above, is the commit/key
5357 pair---i.e., the commit that introduced @file{.guix-authorizations}, and
5358 the fingerprint of the OpenPGP used to sign it.
5361 Before pushing to your public Git repository, you can run @command{guix
5362 git-authenticate} to verify that you did sign all the commits you are
5363 about to push with an authorized key:
5366 guix git authenticate @var{commit} @var{signer}
5370 where @var{commit} and @var{signer} are your channel introduction.
5371 @xref{Invoking guix git authenticate}, for details.
5373 Publishing a signed channel requires discipline: any mistake, such as an
5374 unsigned commit or a commit signed by an unauthorized key, will prevent
5375 users from pulling from your channel---well, that's the whole point of
5376 authentication! Pay attention to merges in particular: merge commits
5377 are considered authentic if and only if they are signed by a key present
5378 in the @file{.guix-authorizations} file of @emph{both} branches.
5381 @section Primary URL
5383 @cindex primary URL, channels
5384 Channel authors can indicate the primary URL of their channel's Git
5385 repository in the @file{.guix-channel} file, like so:
5390 (url "https://example.org/guix.git"))
5393 This allows @command{guix pull} to determine whether it is pulling code
5394 from a mirror of the channel; when that is the case, it warns the user
5395 that the mirror might be stale and displays the primary URL@. That way,
5396 users cannot be tricked into fetching code from a stale mirror that does
5397 not receive security updates.
5399 This feature only makes sense for authenticated repositories, such as
5400 the official @code{guix} channel, for which @command{guix pull} ensures
5401 the code it fetches is authentic.
5403 @node Writing Channel News
5404 @section Writing Channel News
5406 @cindex news, for channels
5407 Channel authors may occasionally want to communicate to their users
5408 information about important changes in the channel. You'd send them all
5409 an email, but that's not convenient.
5411 Instead, channels can provide a @dfn{news file}; when the channel users
5412 run @command{guix pull}, that news file is automatically read and
5413 @command{guix pull --news} can display the announcements that correspond
5414 to the new commits that have been pulled, if any.
5416 To do that, channel authors must first declare the name of the news file
5417 in their @file{.guix-channel} file:
5422 (news-file "etc/news.txt"))
5425 The news file itself, @file{etc/news.txt} in this example, must look
5426 something like this:
5431 (entry (tag "the-bug-fix")
5432 (title (en "Fixed terrible bug")
5434 (body (en "@@emph@{Good news@}! It's fixed!")
5435 (eo "Certe ĝi pli bone funkcias nun!")))
5436 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
5437 (title (en "Added a great package")
5438 (ca "Què vol dir guix?"))
5439 (body (en "Don't miss the @@code@{hello@} package!"))))
5442 While the news file is using the Scheme syntax, avoid naming it with a
5443 @file{.scm} extension or else it will get picked up when building the
5444 channel and yield an error since it is not a valid module.
5445 Alternatively, you can move the channel module to a subdirectory and
5446 store the news file in another directory.
5448 The file consists of a list of @dfn{news entries}. Each entry is
5449 associated with a commit or tag: it describes changes made in this
5450 commit, possibly in preceding commits as well. Users see entries only
5451 the first time they obtain the commit the entry refers to.
5453 The @code{title} field should be a one-line summary while @code{body}
5454 can be arbitrarily long, and both can contain Texinfo markup
5455 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
5456 a list of language tag/message tuples, which allows @command{guix pull}
5457 to display news in the language that corresponds to the user's locale.
5459 If you want to translate news using a gettext-based workflow, you can
5460 extract translatable strings with @command{xgettext} (@pxref{xgettext
5461 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
5462 you write news entries in English first, the command below creates a PO
5463 file containing the strings to translate:
5466 xgettext -o news.po -l scheme -ken etc/news.txt
5469 To sum up, yes, you could use your channel as a blog. But beware, this
5470 is @emph{not quite} what your users might expect.
5472 @node Channels with Substitutes
5473 @section Channels with Substitutes
5475 When running @command{guix pull}, Guix will first compile the
5476 definitions of every available package. This is an expensive operation
5477 for which substitutes (@pxref{Substitutes}) may be available. The
5478 following snippet in @file{channels.scm} will ensure that @command{guix
5479 pull} uses the latest commit with available substitutes for the package
5480 definitions: this is done by querying the continuous integration
5481 server at @url{https://ci.guix.gnu.org}.
5484 (use-modules (guix ci))
5486 (list (channel-with-substitutes-available
5487 %default-guix-channel
5488 "https://ci.guix.gnu.org"))
5491 Note that this does not mean that all the packages that you will
5492 install after running @command{guix pull} will have available
5493 substitutes. It only ensures that @command{guix pull} will not try to
5494 compile package definitions. This is particularly useful when using
5495 machines with limited resources.
5497 @c *********************************************************************
5499 @chapter Development
5501 @cindex software development
5502 If you are a software developer, Guix provides tools that you should find
5503 helpful---independently of the language you're developing in. This is what
5504 this chapter is about.
5506 The @command{guix environment} command provides a convenient way to set up
5507 @dfn{development environments} containing all the dependencies and tools
5508 necessary to work on the software package of your choice. The @command{guix
5509 pack} command allows you to create @dfn{application bundles} that can be
5510 easily distributed to users who do not run Guix.
5513 * Invoking guix environment:: Setting up development environments.
5514 * Invoking guix pack:: Creating software bundles.
5515 * The GCC toolchain:: Working with languages supported by GCC.
5516 * Invoking guix git authenticate:: Authenticating Git repositories.
5519 @node Invoking guix environment
5520 @section Invoking @command{guix environment}
5522 @cindex reproducible build environments
5523 @cindex development environments
5524 @cindex @command{guix environment}
5525 @cindex environment, package build environment
5526 The purpose of @command{guix environment} is to assist hackers in
5527 creating reproducible development environments without polluting their
5528 package profile. The @command{guix environment} tool takes one or more
5529 packages, builds all of their inputs, and creates a shell
5530 environment to use them.
5532 The general syntax is:
5535 guix environment @var{options} @var{package}@dots{}
5538 The following example spawns a new shell set up for the development of
5542 guix environment guile
5545 If the needed dependencies are not built yet, @command{guix environment}
5546 automatically builds them. The environment of the new shell is an
5547 augmented version of the environment that @command{guix environment} was
5548 run in. It contains the necessary search paths for building the given
5549 package added to the existing environment variables. To create
5550 a ``pure'' environment, in which the original environment variables have
5551 been unset, use the @option{--pure} option@footnote{Users sometimes
5552 wrongfully augment environment variables such as @env{PATH} in their
5553 @file{~/.bashrc} file. As a consequence, when @command{guix
5554 environment} launches it, Bash may read @file{~/.bashrc}, thereby
5555 introducing ``impurities'' in these environment variables. It is an
5556 error to define such environment variables in @file{.bashrc}; instead,
5557 they should be defined in @file{.bash_profile}, which is sourced only by
5558 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
5559 Manual}, for details on Bash start-up files.}.
5561 Exiting from a Guix environment is the same as exiting from the shell,
5562 and will place the user back in the old environment before @command{guix
5563 environment} was invoked. The next garbage collection (@pxref{Invoking
5564 guix gc}) will clean up packages that were installed from within the
5565 environment and are no longer used outside of it.
5567 @vindex GUIX_ENVIRONMENT
5568 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
5569 variable in the shell it spawns; its value is the file name of the
5570 profile of this environment. This allows users to, say, define a
5571 specific prompt for development environments in their @file{.bashrc}
5572 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
5575 if [ -n "$GUIX_ENVIRONMENT" ]
5577 export PS1="\u@@\h \w [dev]\$ "
5582 ...@: or to browse the profile:
5585 $ ls "$GUIX_ENVIRONMENT/bin"
5588 Additionally, more than one package may be specified, in which case the
5589 union of the inputs for the given packages are used. For example, the
5590 command below spawns a shell where all of the dependencies of both Guile
5591 and Emacs are available:
5594 guix environment guile emacs
5597 Sometimes an interactive shell session is not desired. An arbitrary
5598 command may be invoked by placing the @code{--} token to separate the
5599 command from the rest of the arguments:
5602 guix environment guile -- make -j4
5605 In other situations, it is more convenient to specify the list of
5606 packages needed in the environment. For example, the following command
5607 runs @command{python} from an environment containing Python@tie{}2.7 and
5611 guix environment --ad-hoc python2-numpy python-2.7 -- python
5614 Furthermore, one might want the dependencies of a package and also some
5615 additional packages that are not build-time or runtime dependencies, but
5616 are useful when developing nonetheless. Because of this, the
5617 @option{--ad-hoc} flag is positional. Packages appearing before
5618 @option{--ad-hoc} are interpreted as packages whose dependencies will be
5619 added to the environment. Packages appearing after are interpreted as
5620 packages that will be added to the environment directly. For example,
5621 the following command creates a Guix development environment that
5622 additionally includes Git and strace:
5625 guix environment --pure guix --ad-hoc git strace
5629 Sometimes it is desirable to isolate the environment as much as
5630 possible, for maximal purity and reproducibility. In particular, when
5631 using Guix on a host distro that is not Guix System, it is desirable to
5632 prevent access to @file{/usr/bin} and other system-wide resources from
5633 the development environment. For example, the following command spawns
5634 a Guile REPL in a ``container'' where only the store and the current
5635 working directory are mounted:
5638 guix environment --ad-hoc --container guile -- guile
5642 The @option{--container} option requires Linux-libre 3.19 or newer.
5645 @cindex certificates
5646 Another typical use case for containers is to run security-sensitive
5647 applications such as a web browser. To run Eolie, we must expose and
5648 share some files and directories; we include @code{nss-certs} and expose
5649 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
5650 @env{DISPLAY} environment variable since containerized graphical
5651 applications won't display without it.
5654 guix environment --preserve='^DISPLAY$' --container --network \
5655 --expose=/etc/machine-id \
5656 --expose=/etc/ssl/certs/ \
5657 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
5658 --ad-hoc eolie nss-certs dbus -- eolie
5661 The available options are summarized below.
5664 @item --root=@var{file}
5665 @itemx -r @var{file}
5666 @cindex persistent environment
5667 @cindex garbage collector root, for environments
5668 Make @var{file} a symlink to the profile for this environment, and
5669 register it as a garbage collector root.
5671 This is useful if you want to protect your environment from garbage
5672 collection, to make it ``persistent''.
5674 When this option is omitted, the environment is protected from garbage
5675 collection only for the duration of the @command{guix environment}
5676 session. This means that next time you recreate the same environment,
5677 you could have to rebuild or re-download packages. @xref{Invoking guix
5678 gc}, for more on GC roots.
5680 @item --expression=@var{expr}
5681 @itemx -e @var{expr}
5682 Create an environment for the package or list of packages that
5683 @var{expr} evaluates to.
5685 For example, running:
5688 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
5691 starts a shell with the environment for this specific variant of the
5697 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
5700 starts a shell with all the base system packages available.
5702 The above commands only use the default output of the given packages.
5703 To select other outputs, two element tuples can be specified:
5706 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
5709 @item --load=@var{file}
5710 @itemx -l @var{file}
5711 Create an environment for the package or list of packages that the code
5712 within @var{file} evaluates to.
5714 As an example, @var{file} might contain a definition like this
5715 (@pxref{Defining Packages}):
5718 @verbatiminclude environment-gdb.scm
5721 @item --manifest=@var{file}
5722 @itemx -m @var{file}
5723 Create an environment for the packages contained in the manifest object
5724 returned by the Scheme code in @var{file}. This option can be repeated
5725 several times, in which case the manifests are concatenated.
5727 This is similar to the same-named option in @command{guix package}
5728 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
5732 Include all specified packages in the resulting environment, as if an
5733 @i{ad hoc} package were defined with them as inputs. This option is
5734 useful for quickly creating an environment without having to write a
5735 package expression to contain the desired inputs.
5737 For instance, the command:
5740 guix environment --ad-hoc guile guile-sdl -- guile
5743 runs @command{guile} in an environment where Guile and Guile-SDL are
5746 Note that this example implicitly asks for the default output of
5747 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
5748 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
5749 of @code{glib} (@pxref{Packages with Multiple Outputs}).
5751 This option may be composed with the default behavior of @command{guix
5752 environment}. Packages appearing before @option{--ad-hoc} are
5753 interpreted as packages whose dependencies will be added to the
5754 environment, the default behavior. Packages appearing after are
5755 interpreted as packages that will be added to the environment directly.
5758 Unset existing environment variables when building the new environment, except
5759 those specified with @option{--preserve} (see below). This has the effect of
5760 creating an environment in which search paths only contain package inputs.
5762 @item --preserve=@var{regexp}
5763 @itemx -E @var{regexp}
5764 When used alongside @option{--pure}, preserve the environment variables
5765 matching @var{regexp}---in other words, put them on a ``white list'' of
5766 environment variables that must be preserved. This option can be repeated
5770 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
5774 This example runs @command{mpirun} in a context where the only environment
5775 variables defined are @env{PATH}, environment variables whose name starts
5776 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
5779 @item --search-paths
5780 Display the environment variable definitions that make up the
5783 @item --system=@var{system}
5784 @itemx -s @var{system}
5785 Attempt to build for @var{system}---e.g., @code{i686-linux}.
5790 Run @var{command} within an isolated container. The current working
5791 directory outside the container is mapped inside the container.
5792 Additionally, unless overridden with @option{--user}, a dummy home
5793 directory is created that matches the current user's home directory, and
5794 @file{/etc/passwd} is configured accordingly.
5796 The spawned process runs as the current user outside the container. Inside
5797 the container, it has the same UID and GID as the current user, unless
5798 @option{--user} is passed (see below).
5802 For containers, share the network namespace with the host system.
5803 Containers created without this flag only have access to the loopback
5806 @item --link-profile
5808 For containers, link the environment profile to @file{~/.guix-profile}
5809 within the container and set @code{GUIX_ENVIRONMENT} to that.
5810 This is equivalent to making @file{~/.guix-profile} a symlink to the
5811 actual profile within the container.
5812 Linking will fail and abort the environment if the directory already
5813 exists, which will certainly be the case if @command{guix environment}
5814 was invoked in the user's home directory.
5816 Certain packages are configured to look in @file{~/.guix-profile} for
5817 configuration files and data;@footnote{For example, the
5818 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
5819 for additional fonts.} @option{--link-profile} allows these programs to
5820 behave as expected within the environment.
5822 @item --user=@var{user}
5823 @itemx -u @var{user}
5824 For containers, use the username @var{user} in place of the current
5825 user. The generated @file{/etc/passwd} entry within the container will
5826 contain the name @var{user}, the home directory will be
5827 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
5828 the UID and GID inside the container are 1000. @var{user}
5829 need not exist on the system.
5831 Additionally, any shared or exposed path (see @option{--share} and
5832 @option{--expose} respectively) whose target is within the current user's
5833 home directory will be remapped relative to @file{/home/USER}; this
5834 includes the automatic mapping of the current working directory.
5837 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
5839 guix environment --container --user=foo \
5840 --expose=$HOME/test \
5841 --expose=/tmp/target=$HOME/target
5844 While this will limit the leaking of user identity through home paths
5845 and each of the user fields, this is only one useful component of a
5846 broader privacy/anonymity solution---not one in and of itself.
5849 For containers, the default behavior is to share the current working
5850 directory with the isolated container and immediately change to that
5851 directory within the container. If this is undesirable,
5852 @option{--no-cwd} will cause the current working directory to @emph{not}
5853 be automatically shared and will change to the user's home directory
5854 within the container instead. See also @option{--user}.
5856 @item --expose=@var{source}[=@var{target}]
5857 @itemx --share=@var{source}[=@var{target}]
5858 For containers, @option{--expose} (resp. @option{--share}) exposes the
5859 file system @var{source} from the host system as the read-only
5860 (resp. writable) file system @var{target} within the container. If
5861 @var{target} is not specified, @var{source} is used as the target mount
5862 point in the container.
5864 The example below spawns a Guile REPL in a container in which the user's
5865 home directory is accessible read-only via the @file{/exchange}
5869 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
5874 @command{guix environment}
5875 also supports all of the common build options that @command{guix
5876 build} supports (@pxref{Common Build Options}) as well as package
5877 transformation options (@pxref{Package Transformation Options}).
5879 @node Invoking guix pack
5880 @section Invoking @command{guix pack}
5882 Occasionally you want to pass software to people who are not (yet!)
5883 lucky enough to be using Guix. You'd tell them to run @command{guix
5884 package -i @var{something}}, but that's not possible in this case. This
5885 is where @command{guix pack} comes in.
5888 If you are looking for ways to exchange binaries among machines that
5889 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5890 publish}, and @ref{Invoking guix archive}.
5895 @cindex application bundle
5896 @cindex software bundle
5897 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5898 @dfn{software bundle}: it creates a tarball or some other archive
5899 containing the binaries of the software you're interested in, and all
5900 its dependencies. The resulting archive can be used on any machine that
5901 does not have Guix, and people can run the exact same binaries as those
5902 you have with Guix. The pack itself is created in a bit-reproducible
5903 fashion, so anyone can verify that it really contains the build results
5904 that you pretend to be shipping.
5906 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5907 their dependencies, you can run:
5910 $ guix pack guile emacs geiser
5912 /gnu/store/@dots{}-pack.tar.gz
5915 The result here is a tarball containing a @file{/gnu/store} directory
5916 with all the relevant packages. The resulting tarball contains a
5917 @dfn{profile} with the three packages of interest; the profile is the
5918 same as would be created by @command{guix package -i}. It is this
5919 mechanism that is used to create Guix's own standalone binary tarball
5920 (@pxref{Binary Installation}).
5922 Users of this pack would have to run
5923 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5924 find inconvenient. To work around it, you can create, say, a
5925 @file{/opt/gnu/bin} symlink to the profile:
5928 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5932 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5934 @cindex relocatable binaries, with @command{guix pack}
5935 What if the recipient of your pack does not have root privileges on
5936 their machine, and thus cannot unpack it in the root file system? In
5937 that case, you will want to use the @option{--relocatable} option (see
5938 below). This option produces @dfn{relocatable binaries}, meaning they
5939 they can be placed anywhere in the file system hierarchy: in the example
5940 above, users can unpack your tarball in their home directory and
5941 directly run @file{./opt/gnu/bin/guile}.
5943 @cindex Docker, build an image with guix pack
5944 Alternatively, you can produce a pack in the Docker image format using
5945 the following command:
5948 guix pack -f docker -S /bin=bin guile guile-readline
5952 The result is a tarball that can be passed to the @command{docker load}
5953 command, followed by @code{docker run}:
5956 docker load < @var{file}
5957 docker run -ti guile-guile-readline /bin/guile
5961 where @var{file} is the image returned by @var{guix pack}, and
5962 @code{guile-guile-readline} is its ``image tag''. See the
5963 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5964 documentation} for more information.
5966 @cindex Singularity, build an image with guix pack
5967 @cindex SquashFS, build an image with guix pack
5968 Yet another option is to produce a SquashFS image with the following
5972 guix pack -f squashfs bash guile emacs geiser
5976 The result is a SquashFS file system image that can either be mounted or
5977 directly be used as a file system container image with the
5978 @uref{https://www.sylabs.io/docs/, Singularity container execution
5979 environment}, using commands like @command{singularity shell} or
5980 @command{singularity exec}.
5982 Several command-line options allow you to customize your pack:
5985 @item --format=@var{format}
5986 @itemx -f @var{format}
5987 Produce a pack in the given @var{format}.
5989 The available formats are:
5993 This is the default format. It produces a tarball containing all the
5994 specified binaries and symlinks.
5997 This produces a tarball that follows the
5998 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
5999 Docker Image Specification}. The ``repository name'' as it appears in
6000 the output of the @command{docker images} command is computed from
6001 package names passed on the command line or in the manifest file.
6004 This produces a SquashFS image containing all the specified binaries and
6005 symlinks, as well as empty mount points for virtual file systems like
6009 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
6010 For that reason, @command{guix pack -f squashfs} always implies @code{-S
6011 /bin=bin}. Thus, your @command{guix pack} invocation must always start
6012 with something like:
6015 guix pack -f squashfs bash @dots{}
6018 If you forget the @code{bash} (or similar) package, @command{singularity
6019 run} and @command{singularity exec} will fail with an unhelpful ``no
6020 such file or directory'' message.
6024 @cindex relocatable binaries
6027 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
6028 anywhere in the file system hierarchy and run from there.
6030 When this option is passed once, the resulting binaries require support for
6031 @dfn{user namespaces} in the kernel Linux; when passed
6032 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
6033 PRoot support, can be thought of as the abbreviation of ``Really
6034 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
6035 other techniques if user namespaces are unavailable, and essentially
6036 work anywhere---see below for the implications.
6038 For example, if you create a pack containing Bash with:
6041 guix pack -RR -S /mybin=bin bash
6045 ...@: you can copy that pack to a machine that lacks Guix, and from your
6046 home directory as a normal user, run:
6054 In that shell, if you type @code{ls /gnu/store}, you'll notice that
6055 @file{/gnu/store} shows up and contains all the dependencies of
6056 @code{bash}, even though the machine actually lacks @file{/gnu/store}
6057 altogether! That is probably the simplest way to deploy Guix-built
6058 software on a non-Guix machine.
6061 By default, relocatable binaries rely on the @dfn{user namespace} feature of
6062 the kernel Linux, which allows unprivileged users to mount or change root.
6063 Old versions of Linux did not support it, and some GNU/Linux distributions
6066 To produce relocatable binaries that work even in the absence of user
6067 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
6068 case, binaries will try user namespace support and fall back to another
6069 @dfn{execution engine} if user namespaces are not supported. The
6070 following execution engines are supported:
6074 Try user namespaces and fall back to PRoot if user namespaces are not
6075 supported (see below).
6078 Try user namespaces and fall back to Fakechroot if user namespaces are
6079 not supported (see below).
6082 Run the program through user namespaces and abort if they are not
6086 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
6087 provides the necessary
6088 support for file system virtualization. It achieves that by using the
6089 @code{ptrace} system call on the running program. This approach has the
6090 advantage to work without requiring special kernel support, but it incurs
6091 run-time overhead every time a system call is made.
6094 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
6095 Fakechroot} virtualizes file system accesses by intercepting calls to C
6096 library functions such as @code{open}, @code{stat}, @code{exec}, and so
6097 on. Unlike PRoot, it incurs very little overhead. However, it does not
6098 always work: for example, some file system accesses made from within the
6099 C library are not intercepted, and file system accesses made @i{via}
6100 direct syscalls are not intercepted either, leading to erratic behavior.
6103 @vindex GUIX_EXECUTION_ENGINE
6104 When running a wrapped program, you can explicitly request one of the
6105 execution engines listed above by setting the
6106 @env{GUIX_EXECUTION_ENGINE} environment variable accordingly.
6109 @cindex entry point, for Docker images
6110 @item --entry-point=@var{command}
6111 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
6112 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
6113 support it. @var{command} must be relative to the profile contained in the
6116 The entry point specifies the command that tools like @code{docker run} or
6117 @code{singularity run} automatically start by default. For example, you can
6121 guix pack -f docker --entry-point=bin/guile guile
6124 The resulting pack can easily be loaded and @code{docker run} with no extra
6125 arguments will spawn @code{bin/guile}:
6128 docker load -i pack.tar.gz
6129 docker run @var{image-id}
6132 @item --expression=@var{expr}
6133 @itemx -e @var{expr}
6134 Consider the package @var{expr} evaluates to.
6136 This has the same purpose as the same-named option in @command{guix
6137 build} (@pxref{Additional Build Options, @option{--expression} in
6138 @command{guix build}}).
6140 @item --manifest=@var{file}
6141 @itemx -m @var{file}
6142 Use the packages contained in the manifest object returned by the Scheme
6143 code in @var{file}. This option can be repeated several times, in which
6144 case the manifests are concatenated.
6146 This has a similar purpose as the same-named option in @command{guix
6147 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
6148 same manifest files. It allows you to define a collection of packages
6149 once and use it both for creating profiles and for creating archives
6150 for use on machines that do not have Guix installed. Note that you can
6151 specify @emph{either} a manifest file @emph{or} a list of packages,
6154 @item --system=@var{system}
6155 @itemx -s @var{system}
6156 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
6157 the system type of the build host.
6159 @item --target=@var{triplet}
6160 @cindex cross-compilation
6161 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
6162 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
6163 configuration triplets,, autoconf, Autoconf}).
6165 @item --compression=@var{tool}
6166 @itemx -C @var{tool}
6167 Compress the resulting tarball using @var{tool}---one of @code{gzip},
6168 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
6171 @item --symlink=@var{spec}
6172 @itemx -S @var{spec}
6173 Add the symlinks specified by @var{spec} to the pack. This option can
6174 appear several times.
6176 @var{spec} has the form @code{@var{source}=@var{target}}, where
6177 @var{source} is the symlink that will be created and @var{target} is the
6180 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
6181 symlink pointing to the @file{bin} sub-directory of the profile.
6183 @item --save-provenance
6184 Save provenance information for the packages passed on the command line.
6185 Provenance information includes the URL and commit of the channels in use
6188 Provenance information is saved in the
6189 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
6190 usual package metadata---the name and version of each package, their
6191 propagated inputs, and so on. It is useful information to the recipient of
6192 the pack, who then knows how the pack was (supposedly) obtained.
6194 This option is not enabled by default because, like timestamps, provenance
6195 information contributes nothing to the build process. In other words, there
6196 is an infinity of channel URLs and commit IDs that can lead to the same pack.
6197 Recording such ``silent'' metadata in the output thus potentially breaks the
6198 source-to-binary bitwise reproducibility property.
6200 @item --root=@var{file}
6201 @itemx -r @var{file}
6202 @cindex garbage collector root, for packs
6203 Make @var{file} a symlink to the resulting pack, and register it as a garbage
6206 @item --localstatedir
6207 @itemx --profile-name=@var{name}
6208 Include the ``local state directory'', @file{/var/guix}, in the resulting
6209 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
6210 profile---by default @var{name} is @code{guix-profile}, which corresponds to
6211 @file{~root/.guix-profile}.
6213 @file{/var/guix} contains the store database (@pxref{The Store}) as well
6214 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
6215 the pack means that the store is ``complete'' and manageable by Guix;
6216 not providing it pack means that the store is ``dead'': items cannot be
6217 added to it or removed from it after extraction of the pack.
6219 One use case for this is the Guix self-contained binary tarball
6220 (@pxref{Binary Installation}).
6224 Print the name of the derivation that builds the pack.
6227 Use the bootstrap binaries to build the pack. This option is only
6228 useful to Guix developers.
6231 In addition, @command{guix pack} supports all the common build options
6232 (@pxref{Common Build Options}) and all the package transformation
6233 options (@pxref{Package Transformation Options}).
6236 @node The GCC toolchain
6237 @section The GCC toolchain
6241 @cindex linker wrapper
6242 @cindex toolchain, for C development
6243 @cindex toolchain, for Fortran development
6245 If you need a complete toolchain for compiling and linking C or C++
6246 source code, use the @code{gcc-toolchain} package. This package
6247 provides a complete GCC toolchain for C/C++ development, including GCC
6248 itself, the GNU C Library (headers and binaries, plus debugging symbols
6249 in the @code{debug} output), Binutils, and a linker wrapper.
6251 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
6252 passed to the linker, add corresponding @code{-rpath} arguments, and
6253 invoke the actual linker with this new set of arguments. You can instruct the
6254 wrapper to refuse to link against libraries not in the store by setting the
6255 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
6257 The package @code{gfortran-toolchain} provides a complete GCC toolchain
6258 for Fortran development. For other languages, please use
6259 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
6262 @node Invoking guix git authenticate
6263 @section Invoking @command{guix git authenticate}
6265 The @command{guix git authenticate} command authenticates a Git checkout
6266 following the same rule as for channels (@pxref{channel-authentication,
6267 channel authentication}). That is, starting from a given commit, it
6268 ensures that all subsequent commits are signed by an OpenPGP key whose
6269 fingerprint appears in the @file{.guix-authorizations} file of its
6272 You will find this command useful if you maintain a channel. But in
6273 fact, this authentication mechanism is useful in a broader context, so
6274 you might want to use it for Git repositories that have nothing to do
6277 The general syntax is:
6280 guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
6283 By default, this command authenticates the Git checkout in the current
6284 directory; it outputs nothing and exits with exit code zero on success
6285 and non-zero on failure. @var{commit} above denotes the first commit
6286 where authentication takes place, and @var{signer} is the OpenPGP
6287 fingerprint of public key used to sign @var{commit}. Together, they
6288 form a ``channel introduction'' (@pxref{channel-authentication, channel
6289 introduction}). The options below allow you to fine-tune the process.
6292 @item --repository=@var{directory}
6293 @itemx -r @var{directory}
6294 Open the Git repository in @var{directory} instead of the current
6297 @item --keyring=@var{reference}
6298 @itemx -k @var{reference}
6299 Load OpenPGP keyring from @var{reference}, the reference of a branch
6300 such as @code{origin/keyring} or @code{my-keyring}. The branch must
6301 contain OpenPGP public keys in @file{.key} files, either in binary form
6302 or ``ASCII-armored''. By default the keyring is loaded from the branch
6303 named @code{keyring}.
6306 Display commit signing statistics upon completion.
6308 @item --cache-key=@var{key}
6309 Previously-authenticated commits are cached in a file under
6310 @file{~/.cache/guix/authentication}. This option forces the cache to be
6311 stored in file @var{key} in that directory.
6313 @item --historical-authorizations=@var{file}
6314 By default, any commit whose parent commit(s) lack the
6315 @file{.guix-authorizations} file is considered inauthentic. In
6316 contrast, this option considers the authorizations in @var{file} for any
6317 commit that lacks @file{.guix-authorizations}. The format of @var{file}
6318 is the same as that of @file{.guix-authorizations}
6319 (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
6323 @c *********************************************************************
6324 @node Programming Interface
6325 @chapter Programming Interface
6327 GNU Guix provides several Scheme programming interfaces (APIs) to
6328 define, build, and query packages. The first interface allows users to
6329 write high-level package definitions. These definitions refer to
6330 familiar packaging concepts, such as the name and version of a package,
6331 its build system, and its dependencies. These definitions can then be
6332 turned into concrete build actions.
6334 Build actions are performed by the Guix daemon, on behalf of users. In a
6335 standard setup, the daemon has write access to the store---the
6336 @file{/gnu/store} directory---whereas users do not. The recommended
6337 setup also has the daemon perform builds in chroots, under specific
6338 build users, to minimize interference with the rest of the system.
6341 Lower-level APIs are available to interact with the daemon and the
6342 store. To instruct the daemon to perform a build action, users actually
6343 provide it with a @dfn{derivation}. A derivation is a low-level
6344 representation of the build actions to be taken, and the environment in
6345 which they should occur---derivations are to package definitions what
6346 assembly is to C programs. The term ``derivation'' comes from the fact
6347 that build results @emph{derive} from them.
6349 This chapter describes all these APIs in turn, starting from high-level
6350 package definitions.
6353 * Package Modules:: Packages from the programmer's viewpoint.
6354 * Defining Packages:: Defining new packages.
6355 * Defining Package Variants:: Customizing packages.
6356 * Build Systems:: Specifying how packages are built.
6357 * Build Phases:: Phases of the build process of a package.
6358 * Build Utilities:: Helpers for your package definitions and more.
6359 * The Store:: Manipulating the package store.
6360 * Derivations:: Low-level interface to package derivations.
6361 * The Store Monad:: Purely functional interface to the store.
6362 * G-Expressions:: Manipulating build expressions.
6363 * Invoking guix repl:: Programming Guix in Guile
6366 @node Package Modules
6367 @section Package Modules
6369 From a programming viewpoint, the package definitions of the
6370 GNU distribution are provided by Guile modules in the @code{(gnu packages
6371 @dots{})} name space@footnote{Note that packages under the @code{(gnu
6372 packages @dots{})} module name space are not necessarily ``GNU
6373 packages''. This module naming scheme follows the usual Guile module
6374 naming convention: @code{gnu} means that these modules are distributed
6375 as part of the GNU system, and @code{packages} identifies modules that
6376 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
6377 Reference Manual}). For instance, the @code{(gnu packages emacs)}
6378 module exports a variable named @code{emacs}, which is bound to a
6379 @code{<package>} object (@pxref{Defining Packages}).
6381 The @code{(gnu packages @dots{})} module name space is
6382 automatically scanned for packages by the command-line tools. For
6383 instance, when running @code{guix install emacs}, all the @code{(gnu
6384 packages @dots{})} modules are scanned until one that exports a package
6385 object whose name is @code{emacs} is found. This package search
6386 facility is implemented in the @code{(gnu packages)} module.
6388 @cindex customization, of packages
6389 @cindex package module search path
6390 Users can store package definitions in modules with different
6391 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
6392 name and module name must match. For instance, the @code{(my-packages
6393 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
6394 relative to the load path specified with @option{--load-path} or
6395 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
6396 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
6397 these package definitions visible to the user interfaces:
6401 By adding the directory containing your package modules to the search path
6402 with the @code{-L} flag of @command{guix package} and other commands
6403 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
6404 environment variable described below.
6407 By defining a @dfn{channel} and configuring @command{guix pull} so that it
6408 pulls from it. A channel is essentially a Git repository containing package
6409 modules. @xref{Channels}, for more information on how to define and use
6413 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
6415 @defvr {Environment Variable} GUIX_PACKAGE_PATH
6416 This is a colon-separated list of directories to search for additional
6417 package modules. Directories listed in this variable take precedence
6418 over the own modules of the distribution.
6421 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
6422 each package is built based solely on other packages in the
6423 distribution. The root of this dependency graph is a small set of
6424 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
6425 bootstrap)} module. For more information on bootstrapping,
6426 @pxref{Bootstrapping}.
6428 @node Defining Packages
6429 @section Defining Packages
6431 The high-level interface to package definitions is implemented in the
6432 @code{(guix packages)} and @code{(guix build-system)} modules. As an
6433 example, the package definition, or @dfn{recipe}, for the GNU Hello
6434 package looks like this:
6437 (define-module (gnu packages hello)
6438 #:use-module (guix packages)
6439 #:use-module (guix download)
6440 #:use-module (guix build-system gnu)
6441 #:use-module (guix licenses)
6442 #:use-module (gnu packages gawk))
6444 (define-public hello
6450 (uri (string-append "mirror://gnu/hello/hello-" version
6454 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
6455 (build-system gnu-build-system)
6456 (arguments '(#:configure-flags '("--enable-silent-rules")))
6457 (inputs `(("gawk" ,gawk)))
6458 (synopsis "Hello, GNU world: An example GNU package")
6459 (description "Guess what GNU Hello prints!")
6460 (home-page "https://www.gnu.org/software/hello/")
6465 Without being a Scheme expert, the reader may have guessed the meaning
6466 of the various fields here. This expression binds the variable
6467 @code{hello} to a @code{<package>} object, which is essentially a record
6468 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
6469 This package object can be inspected using procedures found in the
6470 @code{(guix packages)} module; for instance, @code{(package-name hello)}
6471 returns---surprise!---@code{"hello"}.
6473 With luck, you may be able to import part or all of the definition of
6474 the package you are interested in from another repository, using the
6475 @code{guix import} command (@pxref{Invoking guix import}).
6477 In the example above, @code{hello} is defined in a module of its own,
6478 @code{(gnu packages hello)}. Technically, this is not strictly
6479 necessary, but it is convenient to do so: all the packages defined in
6480 modules under @code{(gnu packages @dots{})} are automatically known to
6481 the command-line tools (@pxref{Package Modules}).
6483 There are a few points worth noting in the above package definition:
6487 The @code{source} field of the package is an @code{<origin>} object
6488 (@pxref{origin Reference}, for the complete reference).
6489 Here, the @code{url-fetch} method from @code{(guix download)} is used,
6490 meaning that the source is a file to be downloaded over FTP or HTTP.
6492 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
6493 the GNU mirrors defined in @code{(guix download)}.
6495 The @code{sha256} field specifies the expected SHA256 hash of the file
6496 being downloaded. It is mandatory, and allows Guix to check the
6497 integrity of the file. The @code{(base32 @dots{})} form introduces the
6498 base32 representation of the hash. You can obtain this information with
6499 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
6500 hash} (@pxref{Invoking guix hash}).
6503 When needed, the @code{origin} form can also have a @code{patches} field
6504 listing patches to be applied, and a @code{snippet} field giving a
6505 Scheme expression to modify the source code.
6508 @cindex GNU Build System
6509 The @code{build-system} field specifies the procedure to build the
6510 package (@pxref{Build Systems}). Here, @code{gnu-build-system}
6511 represents the familiar GNU Build System, where packages may be
6512 configured, built, and installed with the usual @code{./configure &&
6513 make && make check && make install} command sequence.
6515 When you start packaging non-trivial software, you may need tools to
6516 manipulate those build phases, manipulate files, and so on. @xref{Build
6517 Utilities}, for more on this.
6520 The @code{arguments} field specifies options for the build system
6521 (@pxref{Build Systems}). Here it is interpreted by
6522 @code{gnu-build-system} as a request run @file{configure} with the
6523 @option{--enable-silent-rules} flag.
6529 What about these quote (@code{'}) characters? They are Scheme syntax to
6530 introduce a literal list; @code{'} is synonymous with @code{quote}.
6531 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
6532 for details. Here the value of the @code{arguments} field is a list of
6533 arguments passed to the build system down the road, as with @code{apply}
6534 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
6537 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
6538 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
6539 @code{#:configure-flags} is a keyword used to pass a keyword argument
6540 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
6544 The @code{inputs} field specifies inputs to the build process---i.e.,
6545 build-time or run-time dependencies of the package. Here, we define an
6546 input called @code{"gawk"} whose value is that of the @code{gawk}
6547 variable; @code{gawk} is itself bound to a @code{<package>} object.
6549 @cindex backquote (quasiquote)
6552 @cindex comma (unquote)
6556 @findex unquote-splicing
6557 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
6558 us to introduce a literal list in the @code{inputs} field, while
6559 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
6560 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
6563 Note that GCC, Coreutils, Bash, and other essential tools do not need to
6564 be specified as inputs here. Instead, @code{gnu-build-system} takes care
6565 of ensuring that they are present (@pxref{Build Systems}).
6567 However, any other dependencies need to be specified in the
6568 @code{inputs} field. Any dependency not specified here will simply be
6569 unavailable to the build process, possibly leading to a build failure.
6572 @xref{package Reference}, for a full description of possible fields.
6574 Once a package definition is in place, the
6575 package may actually be built using the @code{guix build} command-line
6576 tool (@pxref{Invoking guix build}), troubleshooting any build failures
6577 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
6578 package definition using the @command{guix edit} command
6579 (@pxref{Invoking guix edit}).
6580 @xref{Packaging Guidelines}, for
6581 more information on how to test package definitions, and
6582 @ref{Invoking guix lint}, for information on how to check a definition
6583 for style conformance.
6584 @vindex GUIX_PACKAGE_PATH
6585 Lastly, @pxref{Channels}, for information
6586 on how to extend the distribution by adding your own package definitions
6589 Finally, updating the package definition to a new upstream version
6590 can be partly automated by the @command{guix refresh} command
6591 (@pxref{Invoking guix refresh}).
6593 Behind the scenes, a derivation corresponding to the @code{<package>}
6594 object is first computed by the @code{package-derivation} procedure.
6595 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
6596 The build actions it prescribes may then be realized by using the
6597 @code{build-derivations} procedure (@pxref{The Store}).
6599 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
6600 Return the @code{<derivation>} object of @var{package} for @var{system}
6601 (@pxref{Derivations}).
6603 @var{package} must be a valid @code{<package>} object, and @var{system}
6604 must be a string denoting the target system type---e.g.,
6605 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
6606 must be a connection to the daemon, which operates on the store
6607 (@pxref{The Store}).
6611 @cindex cross-compilation
6612 Similarly, it is possible to compute a derivation that cross-builds a
6613 package for some other system:
6615 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
6616 @var{package} @var{target} [@var{system}]
6617 Return the @code{<derivation>} object of @var{package} cross-built from
6618 @var{system} to @var{target}.
6620 @var{target} must be a valid GNU triplet denoting the target hardware
6621 and operating system, such as @code{"aarch64-linux-gnu"}
6622 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
6625 Once you have package definitions, you can easily define @emph{variants}
6626 of those packages. @xref{Defining Package Variants}, for more on that.
6629 * package Reference:: The package data type.
6630 * origin Reference:: The origin data type.
6634 @node package Reference
6635 @subsection @code{package} Reference
6637 This section summarizes all the options available in @code{package}
6638 declarations (@pxref{Defining Packages}).
6640 @deftp {Data Type} package
6641 This is the data type representing a package recipe.
6645 The name of the package, as a string.
6647 @item @code{version}
6648 The version of the package, as a string.
6651 An object telling how the source code for the package should be
6652 acquired. Most of the time, this is an @code{origin} object, which
6653 denotes a file fetched from the Internet (@pxref{origin Reference}). It
6654 can also be any other ``file-like'' object such as a @code{local-file},
6655 which denotes a file from the local file system (@pxref{G-Expressions,
6656 @code{local-file}}).
6658 @item @code{build-system}
6659 The build system that should be used to build the package (@pxref{Build
6662 @item @code{arguments} (default: @code{'()})
6663 The arguments that should be passed to the build system. This is a
6664 list, typically containing sequential keyword-value pairs.
6666 @item @code{inputs} (default: @code{'()})
6667 @itemx @code{native-inputs} (default: @code{'()})
6668 @itemx @code{propagated-inputs} (default: @code{'()})
6669 @cindex inputs, of packages
6670 These fields list dependencies of the package. Each one is a list of
6671 tuples, where each tuple has a label for the input (a string) as its
6672 first element, a package, origin, or derivation as its second element,
6673 and optionally the name of the output thereof that should be used, which
6674 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
6675 more on package outputs). For example, the list below specifies three
6679 `(("libffi" ,libffi)
6680 ("libunistring" ,libunistring)
6681 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
6684 @cindex cross compilation, package dependencies
6685 The distinction between @code{native-inputs} and @code{inputs} is
6686 necessary when considering cross-compilation. When cross-compiling,
6687 dependencies listed in @code{inputs} are built for the @emph{target}
6688 architecture; conversely, dependencies listed in @code{native-inputs}
6689 are built for the architecture of the @emph{build} machine.
6691 @code{native-inputs} is typically used to list tools needed at
6692 build time, but not at run time, such as Autoconf, Automake, pkg-config,
6693 Gettext, or Bison. @command{guix lint} can report likely mistakes in
6694 this area (@pxref{Invoking guix lint}).
6696 @anchor{package-propagated-inputs}
6697 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
6698 specified packages will be automatically installed to profiles
6699 (@pxref{Features, the role of profiles in Guix}) alongside the package
6700 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
6701 package}}, for information on how @command{guix package} deals with
6704 For example this is necessary when packaging a C/C++ library that needs
6705 headers of another library to compile, or when a pkg-config file refers
6706 to another one @i{via} its @code{Requires} field.
6708 Another example where @code{propagated-inputs} is useful is for languages
6709 that lack a facility to record the run-time search path akin to the
6710 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
6711 more. When packaging libraries written in those languages, ensure they
6712 can find library code they depend on at run time by listing run-time
6713 dependencies in @code{propagated-inputs} rather than @code{inputs}.
6715 @item @code{outputs} (default: @code{'("out")})
6716 The list of output names of the package. @xref{Packages with Multiple
6717 Outputs}, for typical uses of additional outputs.
6719 @item @code{native-search-paths} (default: @code{'()})
6720 @itemx @code{search-paths} (default: @code{'()})
6721 A list of @code{search-path-specification} objects describing
6722 search-path environment variables honored by the package.
6724 @item @code{replacement} (default: @code{#f})
6725 This must be either @code{#f} or a package object that will be used as a
6726 @dfn{replacement} for this package. @xref{Security Updates, grafts},
6729 @item @code{synopsis}
6730 A one-line description of the package.
6732 @item @code{description}
6733 A more elaborate description of the package.
6735 @item @code{license}
6736 @cindex license, of packages
6737 The license of the package; a value from @code{(guix licenses)},
6738 or a list of such values.
6740 @item @code{home-page}
6741 The URL to the home-page of the package, as a string.
6743 @item @code{supported-systems} (default: @code{%supported-systems})
6744 The list of systems supported by the package, as strings of the form
6745 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
6747 @item @code{location} (default: source location of the @code{package} form)
6748 The source location of the package. It is useful to override this when
6749 inheriting from another package, in which case this field is not
6750 automatically corrected.
6754 @deffn {Scheme Syntax} this-package
6755 When used in the @emph{lexical scope} of a package field definition, this
6756 identifier resolves to the package being defined.
6758 The example below shows how to add a package as a native input of itself when
6766 ;; When cross-compiled, Guile, for example, depends on
6767 ;; a native version of itself. Add it here.
6768 (native-inputs (if (%current-target-system)
6769 `(("self" ,this-package))
6773 It is an error to refer to @code{this-package} outside a package definition.
6776 Because packages are regular Scheme objects that capture a complete
6777 dependency graph and associated build procedures, it is often useful to
6778 write procedures that take a package and return a modified version
6779 thereof according to some parameters. Below are a few examples.
6781 @cindex tool chain, choosing a package's tool chain
6782 @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
6783 Return a variant of @var{package} that uses @var{toolchain} instead of
6784 the default GNU C/C++ toolchain. @var{toolchain} must be a list of
6785 inputs (label/package tuples) providing equivalent functionality, such
6786 as the @code{gcc-toolchain} package.
6788 The example below returns a variant of the @code{hello} package built
6789 with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
6790 GNU C Library) instead of the default tool chain:
6793 (let ((toolchain (specification->package "gcc-toolchain@@10")))
6794 (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
6797 The build tool chain is part of the @dfn{implicit inputs} of
6798 packages---it's usually not listed as part of the various ``inputs''
6799 fields and is instead pulled in by the build system. Consequently, this
6800 procedure works by changing the build system of @var{package} so that it
6801 pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
6802 for more on build systems.
6805 @node origin Reference
6806 @subsection @code{origin} Reference
6808 This section documents @dfn{origins}. An @code{origin} declaration
6809 specifies data that must be ``produced''---downloaded, usually---and
6810 whose content hash is known in advance. Origins are primarily used to
6811 represent the source code of packages (@pxref{Defining Packages}). For
6812 that reason, the @code{origin} form allows you to declare patches to
6813 apply to the original source code as well as code snippets to modify it.
6815 @deftp {Data Type} origin
6816 This is the data type representing a source code origin.
6820 An object containing the URI of the source. The object type depends on
6821 the @code{method} (see below). For example, when using the
6822 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
6823 values are: a URL represented as a string, or a list thereof.
6825 @cindex fixed-output derivations, for download
6827 A monadic procedure that handles the given URI@. The procedure must
6828 accept at least three arguments: the value of the @code{uri} field and
6829 the hash algorithm and hash value specified by the @code{hash} field.
6830 It must return a store item or a derivation in the store monad
6831 (@pxref{The Store Monad}); most methods return a fixed-output derivation
6832 (@pxref{Derivations}).
6834 Commonly used methods include @code{url-fetch}, which fetches data from
6835 a URL, and @code{git-fetch}, which fetches data from a Git repository
6839 A bytevector containing the SHA-256 hash of the source. This is
6840 equivalent to providing a @code{content-hash} SHA256 object in the
6841 @code{hash} field described below.
6844 The @code{content-hash} object of the source---see below for how to use
6845 @code{content-hash}.
6847 You can obtain this information using @code{guix download}
6848 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
6851 @item @code{file-name} (default: @code{#f})
6852 The file name under which the source code should be saved. When this is
6853 @code{#f}, a sensible default value will be used in most cases. In case
6854 the source is fetched from a URL, the file name from the URL will be
6855 used. For version control checkouts, it is recommended to provide the
6856 file name explicitly because the default is not very descriptive.
6858 @item @code{patches} (default: @code{'()})
6859 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
6860 file-like objects}) pointing to patches to be applied to the source.
6862 This list of patches must be unconditional. In particular, it cannot
6863 depend on the value of @code{%current-system} or
6864 @code{%current-target-system}.
6866 @item @code{snippet} (default: @code{#f})
6867 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
6868 in the source directory. This is a convenient way to modify the source,
6869 sometimes more convenient than a patch.
6871 @item @code{patch-flags} (default: @code{'("-p1")})
6872 A list of command-line flags that should be passed to the @code{patch}
6875 @item @code{patch-inputs} (default: @code{#f})
6876 Input packages or derivations to the patching process. When this is
6877 @code{#f}, the usual set of inputs necessary for patching are provided,
6878 such as GNU@tie{}Patch.
6880 @item @code{modules} (default: @code{'()})
6881 A list of Guile modules that should be loaded during the patching
6882 process and while running the code in the @code{snippet} field.
6884 @item @code{patch-guile} (default: @code{#f})
6885 The Guile package that should be used in the patching process. When
6886 this is @code{#f}, a sensible default is used.
6890 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
6891 Construct a content hash object for the given @var{algorithm}, and with
6892 @var{value} as its hash value. When @var{algorithm} is omitted, assume
6893 it is @code{sha256}.
6895 @var{value} can be a literal string, in which case it is base32-decoded,
6896 or it can be a bytevector.
6898 The following forms are all equivalent:
6901 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
6902 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
6904 (content-hash (base32
6905 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
6906 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
6910 Technically, @code{content-hash} is currently implemented as a macro.
6911 It performs sanity checks at macro-expansion time, when possible, such
6912 as ensuring that @var{value} has the right size for @var{algorithm}.
6915 As we have seen above, how exactly the data an origin refers to is
6916 retrieved is determined by its @code{method} field. The @code{(guix
6917 download)} module provides the most common method, @code{url-fetch},
6920 @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
6921 [name] [#:executable? #f]
6922 Return a fixed-output derivation that fetches data from @var{url} (a
6923 string, or a list of strings denoting alternate URLs), which is expected
6924 to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
6925 the file name is the base name of URL; optionally, @var{name} can
6926 specify a different file name. When @var{executable?} is true, make the
6927 downloaded file executable.
6929 When one of the URL starts with @code{mirror://}, then its host part is
6930 interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
6932 Alternatively, when URL starts with @code{file://}, return the
6933 corresponding file name in the store.
6936 Likewise, the @code{(guix git-download)} module defines the
6937 @code{git-fetch} origin method, which fetches data from a Git version
6938 control repository, and the @code{git-reference} data type to describe
6939 the repository and revision to fetch.
6941 @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
6942 Return a fixed-output derivation that fetches @var{ref}, a
6943 @code{<git-reference>} object. The output is expected to have recursive
6944 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
6945 the file name, or a generic name if @code{#f}.
6948 @deftp {Data Type} git-reference
6949 This data type represents a Git reference for @code{git-fetch} to
6954 The URL of the Git repository to clone.
6957 This string denotes either the commit to fetch (a hexadecimal string,
6958 either the full SHA1 commit or a ``short'' commit string; the latter is
6959 not recommended) or the tag to fetch.
6961 @item @code{recursive?} (default: @code{#f})
6962 This Boolean indicates whether to recursively fetch Git sub-modules.
6965 The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
6970 (url "https://git.savannah.gnu.org/git/hello.git")
6974 This is equivalent to the reference below, which explicitly names the
6979 (url "https://git.savannah.gnu.org/git/hello.git")
6980 (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
6984 For Mercurial repositories, the module @code{(guix hg-download)} defines
6985 the @code{hg-fetch} origin method and @code{hg-reference} data type for
6986 support of the Mercurial version control system.
6988 @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
6990 Return a fixed-output derivation that fetches @var{ref}, a
6991 @code{<hg-reference>} object. The output is expected to have recursive
6992 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
6993 the file name, or a generic name if @code{#false}.
6996 @node Defining Package Variants
6997 @section Defining Package Variants
6999 @cindex customizing packages
7000 @cindex variants, of packages
7001 One of the nice things with Guix is that, given a package definition,
7002 you can easily @emph{derive} variants of that package---for a different
7003 upstream version, with different dependencies, different compilation
7004 options, and so on. Some of these custom packages can be defined
7005 straight from the command line (@pxref{Package Transformation Options}).
7006 This section describes how to define package variants in code. This can
7007 be useful in ``manifests'' (@pxref{profile-manifest,
7008 @option{--manifest}}) and in your own package collection
7009 (@pxref{Creating a Channel}), among others!
7011 @cindex inherit, for package definitions
7012 As discussed earlier, packages are first-class objects in the Scheme
7013 language. The @code{(guix packages)} module provides the @code{package}
7014 construct to define new package objects (@pxref{package Reference}).
7015 The easiest way to define a package variant is using the @code{inherit}
7016 keyword together with @code{package}. This allows you to inherit from a
7017 package definition while overriding the fields you want.
7019 For example, given the @code{hello} variable, which contains a
7020 definition for the current version of GNU@tie{}Hello, here's how you
7021 would define a variant for version 2.2 (released in 2006, it's
7025 (use-modules (gnu packages base)) ;for 'hello'
7033 (uri (string-append "mirror://gnu/hello/hello-" version
7037 "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
7040 The example above corresponds to what the @option{--with-source} package
7041 transformation option does. Essentially @code{hello-2.2} preserves all
7042 the fields of @code{hello}, except @code{version} and @code{source},
7043 which it overrides. Note that the original @code{hello} variable is
7044 still there, in the @code{(gnu packages base)} module, unchanged. When
7045 you define a custom package like this, you are really @emph{adding} a
7046 new package definition; the original one remains available.
7048 You can just as well define variants with a different set of
7049 dependencies than the original package. For example, the default
7050 @code{gdb} package depends on @code{guile}, but since that is an
7051 optional dependency, you can define a variant that removes that
7055 (use-modules (gnu packages gdb) ;for 'gdb'
7056 (srfi srfi-1)) ;for 'alist-delete'
7058 (define gdb-sans-guile
7061 (inputs (alist-delete "guile"
7062 (package-inputs gdb)))))
7065 The @code{alist-delete} call above removes the tuple from the
7066 @code{inputs} field that has @code{"guile"} as its first element
7067 (@pxref{SRFI-1 Association Lists,,, guile, GNU Guile Reference
7070 In some cases, you may find it useful to write functions
7071 (``procedures'', in Scheme parlance) that return a package based on some
7072 parameters. For example, consider the @code{luasocket} library for the
7073 Lua programming language. We want to create @code{luasocket} packages
7074 for major versions of Lua. One way to do that is to define a procedure
7075 that takes a Lua package and returns a @code{luasocket} package that
7079 (define (make-lua-socket name lua)
7080 ;; Return a luasocket package built with LUA.
7084 ;; several fields omitted
7087 (synopsis "Socket library for Lua")))
7089 (define-public lua5.1-socket
7090 (make-lua-socket "lua5.1-socket" lua-5.1))
7092 (define-public lua5.2-socket
7093 (make-lua-socket "lua5.2-socket" lua-5.2))
7096 Here we have defined packages @code{lua5.1-socket} and
7097 @code{lua5.2-socket} by calling @code{make-lua-socket} with different
7098 arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
7099 more info on procedures. Having top-level public definitions for these
7100 two packages means that they can be referred to from the command line
7101 (@pxref{Package Modules}).
7103 @cindex package transformations
7104 These are pretty simple package variants. As a convenience, the
7105 @code{(guix transformations)} module provides a high-level interface
7106 that directly maps to the more sophisticated package transformation
7107 options (@pxref{Package Transformation Options}):
7109 @deffn {Scheme Procedure} options->transformation @var{opts}
7110 Return a procedure that, when passed an object to build (package,
7111 derivation, etc.), applies the transformations specified by @var{opts} and returns
7112 the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
7115 ((with-branch . "guile-gcrypt=master")
7116 (without-tests . "libgcrypt"))
7119 Each symbol names a transformation and the corresponding string is an argument
7120 to that transformation.
7123 For instance, a manifest equivalent to this command:
7127 --with-branch=guile-gcrypt=master \
7128 --with-debug-info=zlib
7132 ... would look like this:
7135 (use-modules (guix transformations))
7138 ;; The package transformation procedure.
7139 (options->transformation
7140 '((with-branch . "guile-gcrypt=master")
7141 (with-debug-info . "zlib"))))
7144 (list (transform (specification->package "guix"))))
7147 @cindex input rewriting
7148 @cindex dependency graph rewriting
7149 The @code{options->transformation} procedure is convenient, but it's
7150 perhaps also not as flexible as you may like. How is it implemented?
7151 The astute reader probably noticed that most package transformation
7152 options go beyond the superficial changes shown in the first examples of
7153 this section: they involve @dfn{input rewriting}, whereby the dependency
7154 graph of a package is rewritten by replacing specific inputs by others.
7156 Dependency graph rewriting, for the purposes of swapping packages in the
7157 graph, is what the @code{package-input-rewriting} procedure in
7158 @code{(guix packages)} implements.
7160 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
7161 [@var{rewrite-name}] [#:deep? #t]
7162 Return a procedure that, when passed a package, replaces its direct and
7163 indirect dependencies, including implicit inputs when @var{deep?} is
7164 true, according to @var{replacements}. @var{replacements} is a list of
7165 package pairs; the first element of each pair is the package to replace,
7166 and the second one is the replacement.
7168 Optionally, @var{rewrite-name} is a one-argument procedure that takes
7169 the name of a package and returns its new name after rewrite.
7173 Consider this example:
7176 (define libressl-instead-of-openssl
7177 ;; This is a procedure to replace OPENSSL by LIBRESSL,
7179 (package-input-rewriting `((,openssl . ,libressl))))
7181 (define git-with-libressl
7182 (libressl-instead-of-openssl git))
7186 Here we first define a rewriting procedure that replaces @var{openssl}
7187 with @var{libressl}. Then we use it to define a @dfn{variant} of the
7188 @var{git} package that uses @var{libressl} instead of @var{openssl}.
7189 This is exactly what the @option{--with-input} command-line option does
7190 (@pxref{Package Transformation Options, @option{--with-input}}).
7192 The following variant of @code{package-input-rewriting} can match packages to
7193 be replaced by name rather than by identity.
7195 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
7196 Return a procedure that, given a package, applies the given
7197 @var{replacements} to all the package graph, including implicit inputs
7198 unless @var{deep?} is false. @var{replacements} is a list of
7199 spec/procedures pair; each spec is a package specification such as
7200 @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
7201 package and returns a replacement for that package.
7204 The example above could be rewritten this way:
7207 (define libressl-instead-of-openssl
7208 ;; Replace all the packages called "openssl" with LibreSSL.
7209 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
7212 The key difference here is that, this time, packages are matched by spec and
7213 not by identity. In other words, any package in the graph that is called
7214 @code{openssl} will be replaced.
7216 A more generic procedure to rewrite a package dependency graph is
7217 @code{package-mapping}: it supports arbitrary changes to nodes in the
7220 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
7221 Return a procedure that, given a package, applies @var{proc} to all the packages
7222 depended on and returns the resulting package. The procedure stops recursion
7223 when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
7224 applied to implicit inputs as well.
7229 @section Build Systems
7231 @cindex build system
7232 Each package definition specifies a @dfn{build system} and arguments for
7233 that build system (@pxref{Defining Packages}). This @code{build-system}
7234 field represents the build procedure of the package, as well as implicit
7235 dependencies of that build procedure.
7237 Build systems are @code{<build-system>} objects. The interface to
7238 create and manipulate them is provided by the @code{(guix build-system)}
7239 module, and actual build systems are exported by specific modules.
7241 @cindex bag (low-level package representation)
7242 Under the hood, build systems first compile package objects to
7243 @dfn{bags}. A @dfn{bag} is like a package, but with less
7244 ornamentation---in other words, a bag is a lower-level representation of
7245 a package, which includes all the inputs of that package, including some
7246 that were implicitly added by the build system. This intermediate
7247 representation is then compiled to a derivation (@pxref{Derivations}).
7248 The @code{package-with-c-toolchain} is an example of a way to change the
7249 implicit inputs that a package's build system pulls in (@pxref{package
7250 Reference, @code{package-with-c-toolchain}}).
7252 Build systems accept an optional list of @dfn{arguments}. In package
7253 definitions, these are passed @i{via} the @code{arguments} field
7254 (@pxref{Defining Packages}). They are typically keyword arguments
7255 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
7256 Guile Reference Manual}). The value of these arguments is usually
7257 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
7258 by the daemon (@pxref{Derivations}).
7260 The main build system is @code{gnu-build-system}, which implements the
7261 standard build procedure for GNU and many other packages. It
7262 is provided by the @code{(guix build-system gnu)} module.
7264 @defvr {Scheme Variable} gnu-build-system
7265 @code{gnu-build-system} represents the GNU Build System, and variants
7266 thereof (@pxref{Configuration, configuration and makefile conventions,,
7267 standards, GNU Coding Standards}).
7269 @cindex build phases
7270 In a nutshell, packages using it are configured, built, and installed with
7271 the usual @code{./configure && make && make check && make install}
7272 command sequence. In practice, a few additional steps are often needed.
7273 All these steps are split up in separate @dfn{phases},
7274 notably@footnote{Please see the @code{(guix build gnu-build-system)}
7275 modules for more details about the build phases.}:
7279 Unpack the source tarball, and change the current directory to the
7280 extracted source tree. If the source is actually a directory, copy it
7281 to the build tree, and enter that directory.
7283 @item patch-source-shebangs
7284 Patch shebangs encountered in source files so they refer to the right
7285 store file names. For instance, this changes @code{#!/bin/sh} to
7286 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
7289 Run the @file{configure} script with a number of default options, such
7290 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
7291 by the @code{#:configure-flags} argument.
7294 Run @code{make} with the list of flags specified with
7295 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
7296 (the default), build with @code{make -j}.
7299 Run @code{make check}, or some other target specified with
7300 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
7301 @code{#:parallel-tests?} argument is true (the default), run @code{make
7305 Run @code{make install} with the flags listed in @code{#:make-flags}.
7307 @item patch-shebangs
7308 Patch shebangs on the installed executable files.
7311 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
7312 is false), copying them to the @code{debug} output when available
7313 (@pxref{Installing Debugging Files}).
7316 @vindex %standard-phases
7317 The build-side module @code{(guix build gnu-build-system)} defines
7318 @code{%standard-phases} as the default list of build phases.
7319 @code{%standard-phases} is a list of symbol/procedure pairs, where the
7320 procedure implements the actual phase.
7322 @xref{Build Phases}, for more info on build phases and ways to customize
7325 In addition, this build system ensures that the ``standard'' environment
7326 for GNU packages is available. This includes tools such as GCC, libc,
7327 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
7328 build-system gnu)} module for a complete list). We call these the
7329 @dfn{implicit inputs} of a package, because package definitions do not
7330 have to mention them.
7333 Other @code{<build-system>} objects are defined to support other
7334 conventions and tools used by free software packages. They inherit most
7335 of @code{gnu-build-system}, and differ mainly in the set of inputs
7336 implicitly added to the build process, and in the list of phases
7337 executed. Some of these build systems are listed below.
7339 @defvr {Scheme Variable} ant-build-system
7340 This variable is exported by @code{(guix build-system ant)}. It
7341 implements the build procedure for Java packages that can be built with
7342 @url{https://ant.apache.org/, Ant build tool}.
7344 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
7345 provided by the @code{icedtea} package to the set of inputs. Different
7346 packages can be specified with the @code{#:ant} and @code{#:jdk}
7347 parameters, respectively.
7349 When the original package does not provide a suitable Ant build file,
7350 the parameter @code{#:jar-name} can be used to generate a minimal Ant
7351 build file @file{build.xml} with tasks to build the specified jar
7352 archive. In this case the parameter @code{#:source-dir} can be used to
7353 specify the source sub-directory, defaulting to ``src''.
7355 The @code{#:main-class} parameter can be used with the minimal ant
7356 buildfile to specify the main class of the resulting jar. This makes the
7357 jar file executable. The @code{#:test-include} parameter can be used to
7358 specify the list of junit tests to run. It defaults to
7359 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
7360 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
7361 because abstract classes cannot be run as tests.
7363 The parameter @code{#:build-target} can be used to specify the Ant task
7364 that should be run during the @code{build} phase. By default the
7365 ``jar'' task will be run.
7369 @defvr {Scheme Variable} android-ndk-build-system
7370 @cindex Android distribution
7371 @cindex Android NDK build system
7372 This variable is exported by @code{(guix build-system android-ndk)}. It
7373 implements a build procedure for Android NDK (native development kit)
7374 packages using a Guix-specific build process.
7376 The build system assumes that packages install their public interface
7377 (header) files to the subdirectory @file{include} of the @code{out} output and
7378 their libraries to the subdirectory @file{lib} the @code{out} output.
7380 It's also assumed that the union of all the dependencies of a package
7381 has no conflicting files.
7383 For the time being, cross-compilation is not supported - so right now
7384 the libraries and header files are assumed to be host tools.
7388 @defvr {Scheme Variable} asdf-build-system/source
7389 @defvrx {Scheme Variable} asdf-build-system/sbcl
7390 @defvrx {Scheme Variable} asdf-build-system/ecl
7392 These variables, exported by @code{(guix build-system asdf)}, implement
7393 build procedures for Common Lisp packages using
7394 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
7395 definition facility for Common Lisp programs and libraries.
7397 The @code{asdf-build-system/source} system installs the packages in
7398 source form, and can be loaded using any common lisp implementation, via
7399 ASDF@. The others, such as @code{asdf-build-system/sbcl}, install binary
7400 systems in the format which a particular implementation understands.
7401 These build systems can also be used to produce executable programs, or
7402 lisp images which contain a set of packages pre-loaded.
7404 The build system uses naming conventions. For binary packages, the
7405 package name should be prefixed with the lisp implementation, such as
7406 @code{sbcl-} for @code{asdf-build-system/sbcl}.
7408 Additionally, the corresponding source package should be labeled using
7409 the same convention as python packages (see @ref{Python Modules}), using
7410 the @code{cl-} prefix.
7412 In order to create executable programs and images, the build-side
7413 procedures @code{build-program} and @code{build-image} can be used.
7414 They should be called in a build phase after the
7415 @code{create-asdf-configuration} phase, so that the system which was
7416 just built can be used within the resulting image. @code{build-program}
7417 requires a list of Common Lisp expressions to be passed as the
7418 @code{#:entry-program} argument.
7420 By default, all the @file{.asd} files present in the sources are read to
7421 find system definitions. The @code{#:asd-files} parameter can be used
7422 to specify the list of @file{.asd} files to read. Furthermore, if the
7423 package defines a system for its tests in a separate file, it will be
7424 loaded before the tests are run if it is specified by the
7425 @code{#:test-asd-file} parameter. If it is not set, the files
7426 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
7427 and @code{test.asd} will be tried if they exist.
7429 If for some reason the package must be named in a different way than the
7430 naming conventions suggest, or if several systems must be compiled, the
7431 @code{#:asd-systems} parameter can be used to specify the list of system
7436 @defvr {Scheme Variable} cargo-build-system
7437 @cindex Rust programming language
7438 @cindex Cargo (Rust build system)
7439 This variable is exported by @code{(guix build-system cargo)}. It
7440 supports builds of packages using Cargo, the build tool of the
7441 @uref{https://www.rust-lang.org, Rust programming language}.
7443 It adds @code{rustc} and @code{cargo} to the set of inputs.
7444 A different Rust package can be specified with the @code{#:rust} parameter.
7446 Regular cargo dependencies should be added to the package definition via the
7447 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
7448 spec can be a package or a source definition. Note that the spec must
7449 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
7450 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
7451 should be added to the package definition via the
7452 @code{#:cargo-development-inputs} parameter.
7454 In its @code{configure} phase, this build system will make any source inputs
7455 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
7456 parameters available to cargo. It will also remove an included
7457 @code{Cargo.lock} file to be recreated by @code{cargo} during the
7458 @code{build} phase. The @code{install} phase installs the binaries
7459 defined by the crate.
7462 @defvr {Scheme Variable} chicken-build-system
7463 This variable is exported by @code{(guix build-system chicken)}. It
7464 builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
7465 ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
7466 gets compiled by a C compiler, in this case GCC.
7468 This build system adds @code{chicken} to the package inputs, as well as
7469 the packages of @code{gnu-build-system}.
7471 The build system can't (yet) deduce the egg's name automatically, so just like
7472 with @code{go-build-system} and its @code{#:import-path}, you should define
7473 @code{#:egg-name} in the package's @code{arguments} field.
7475 For example, if you are packaging the @code{srfi-1} egg:
7478 (arguments '(#:egg-name "srfi-1"))
7481 Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
7482 because CHICKEN doesn't embed absolute references in compiled eggs.
7483 Test dependencies should go to @code{native-inputs}, as usual.
7486 @defvr {Scheme Variable} copy-build-system
7487 This variable is exported by @code{(guix build-system copy)}. It
7488 supports builds of simple packages that don't require much compiling,
7489 mostly just moving files around.
7491 It adds much of the @code{gnu-build-system} packages to the set of
7492 inputs. Because of this, the @code{copy-build-system} does not require
7493 all the boilerplate code often needed for the
7494 @code{trivial-build-system}.
7496 To further simplify the file installation process, an
7497 @code{#:install-plan} argument is exposed to let the packager specify
7498 which files go where. The install plan is a list of @code{(@var{source}
7499 @var{target} [@var{filters}])}. @var{filters} are optional.
7502 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
7504 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
7505 @item Otherwise install @var{source} as @var{target}.
7508 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
7509 the trailing slash of @var{target} is implied with the same meaning
7512 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
7513 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
7514 @code{#:exclude-regexp}, only select files are installed depending on
7515 the filters. Each filters is specified by a list of strings.
7517 @item With @code{#:include}, install all the files which the path suffix matches
7518 at least one of the elements in the given list.
7519 @item With @code{#:include-regexp}, install all the files which the
7520 subpaths match at least one of the regular expressions in the given
7522 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
7523 are the complement of their inclusion counterpart. Without @code{#:include} flags,
7524 install all files but those matching the exclusion filters.
7525 If both inclusions and exclusions are specified, the exclusions are done
7526 on top of the inclusions.
7529 In all cases, the paths relative to @var{source} are preserved within
7536 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
7537 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
7538 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
7539 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
7540 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
7541 @file{share/my-app/sub/file}.
7542 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
7543 @file{share/my-app/file}.
7548 @cindex Clojure (programming language)
7549 @cindex simple Clojure build system
7550 @defvr {Scheme Variable} clojure-build-system
7551 This variable is exported by @code{(guix build-system clojure)}. It implements
7552 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
7553 using plain old @code{compile} in Clojure. Cross-compilation is not supported
7556 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
7557 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
7558 @code{#:zip} parameters, respectively.
7560 A list of source directories, test directories and jar names can be specified
7561 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
7562 parameters, respectively. Compile directory and main class can be specified
7563 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
7564 Other parameters are documented below.
7566 This build system is an extension of @code{ant-build-system}, but with the
7567 following phases changed:
7572 This phase calls @code{compile} in Clojure to compile source files and runs
7573 @command{jar} to create jars from both source files and compiled files
7574 according to the include list and exclude list specified in
7575 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
7576 has priority over the include list. These lists consist of symbols
7577 representing Clojure libraries or the special keyword @code{#:all} representing
7578 all Clojure libraries found under the source directories. The parameter
7579 @code{#:omit-source?} decides if source should be included into the jars.
7582 This phase runs tests according to the include list and exclude list specified
7583 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
7584 meanings are analogous to that of @code{#:aot-include} and
7585 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
7586 stands for all Clojure libraries found under the test directories. The
7587 parameter @code{#:tests?} decides if tests should be run.
7590 This phase installs all jars built previously.
7593 Apart from the above, this build system also contains an additional phase:
7598 This phase installs all top-level files with base name matching
7599 @code{%doc-regex}. A different regex can be specified with the
7600 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
7601 directories specified in @code{#:doc-dirs} are installed as well.
7605 @defvr {Scheme Variable} cmake-build-system
7606 This variable is exported by @code{(guix build-system cmake)}. It
7607 implements the build procedure for packages using the
7608 @url{https://www.cmake.org, CMake build tool}.
7610 It automatically adds the @code{cmake} package to the set of inputs.
7611 Which package is used can be specified with the @code{#:cmake}
7614 The @code{#:configure-flags} parameter is taken as a list of flags
7615 passed to the @command{cmake} command. The @code{#:build-type}
7616 parameter specifies in abstract terms the flags passed to the compiler;
7617 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
7618 debugging information''), which roughly means that code is compiled with
7619 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
7622 @defvr {Scheme Variable} dune-build-system
7623 This variable is exported by @code{(guix build-system dune)}. It
7624 supports builds of packages using @uref{https://dune.build/, Dune}, a build
7625 tool for the OCaml programming language. It is implemented as an extension
7626 of the @code{ocaml-build-system} which is described below. As such, the
7627 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
7630 It automatically adds the @code{dune} package to the set of inputs.
7631 Which package is used can be specified with the @code{#:dune}
7634 There is no @code{configure} phase because dune packages typically don't
7635 need to be configured. The @code{#:build-flags} parameter is taken as a
7636 list of flags passed to the @code{dune} command during the build.
7638 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
7639 command instead of the more recent @code{dune} command while building
7640 a package. Its default value is @code{#f}.
7642 The @code{#:package} parameter can be passed to specify a package name, which
7643 is useful when a package contains multiple packages and you want to build
7644 only one of them. This is equivalent to passing the @code{-p} argument to
7648 @defvr {Scheme Variable} go-build-system
7649 This variable is exported by @code{(guix build-system go)}. It
7650 implements a build procedure for Go packages using the standard
7651 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
7652 Go build mechanisms}.
7654 The user is expected to provide a value for the key @code{#:import-path}
7655 and, in some cases, @code{#:unpack-path}. The
7656 @url{https://golang.org/doc/code.html#ImportPaths, import path}
7657 corresponds to the file system path expected by the package's build
7658 scripts and any referring packages, and provides a unique way to
7659 refer to a Go package. It is typically based on a combination of the
7660 package source code's remote URI and file system hierarchy structure. In
7661 some cases, you will need to unpack the package's source code to a
7662 different directory structure than the one indicated by the import path,
7663 and @code{#:unpack-path} should be used in such cases.
7665 Packages that provide Go libraries should install their source code into
7666 the built output. The key @code{#:install-source?}, which defaults to
7667 @code{#t}, controls whether or not the source code is installed. It can
7668 be set to @code{#f} for packages that only provide executable files.
7671 @defvr {Scheme Variable} glib-or-gtk-build-system
7672 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
7673 is intended for use with packages making use of GLib or GTK+.
7675 This build system adds the following two phases to the ones defined by
7676 @code{gnu-build-system}:
7679 @item glib-or-gtk-wrap
7680 The phase @code{glib-or-gtk-wrap} ensures that programs in
7681 @file{bin/} are able to find GLib ``schemas'' and
7682 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
7683 modules}. This is achieved by wrapping the programs in launch scripts
7684 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
7685 environment variables.
7687 It is possible to exclude specific package outputs from that wrapping
7688 process by listing their names in the
7689 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
7690 when an output is known not to contain any GLib or GTK+ binaries, and
7691 where wrapping would gratuitously add a dependency of that output on
7694 @item glib-or-gtk-compile-schemas
7695 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
7696 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
7697 GSettings schemas} of GLib are compiled. Compilation is performed by the
7698 @command{glib-compile-schemas} program. It is provided by the package
7699 @code{glib:bin} which is automatically imported by the build system.
7700 The @code{glib} package providing @command{glib-compile-schemas} can be
7701 specified with the @code{#:glib} parameter.
7704 Both phases are executed after the @code{install} phase.
7707 @defvr {Scheme Variable} guile-build-system
7708 This build system is for Guile packages that consist exclusively of Scheme
7709 code and that are so lean that they don't even have a makefile, let alone a
7710 @file{configure} script. It compiles Scheme code using @command{guild
7711 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
7712 installs the @file{.scm} and @file{.go} files in the right place. It also
7713 installs documentation.
7715 This build system supports cross-compilation by using the
7716 @option{--target} option of @samp{guild compile}.
7718 Packages built with @code{guile-build-system} must provide a Guile package in
7719 their @code{native-inputs} field.
7722 @defvr {Scheme Variable} julia-build-system
7723 This variable is exported by @code{(guix build-system julia)}. It
7724 implements the build procedure used by @uref{https://julialang.org/,
7725 julia} packages, which essentially is similar to running @samp{julia -e
7726 'using Pkg; Pkg.add(package)'} in an environment where
7727 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
7728 Tests are run by calling @code{/test/runtests.jl}.
7730 The Julia package name is read from the file @file{Project.toml}. This
7731 value can be overridden by passing the argument @code{#:julia-file-name}
7732 (which must be correctly capitalized).
7734 For packages requiring shared library dependencies, you may need to write the
7735 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
7736 variable = /gnu/store/library.so} for each dependency, plus a void function
7737 @code{check_deps() = nothing}.
7739 Some older packages that aren't using @file{Package.toml} yet, will require
7740 this file to be created, too. The function @code{julia-create-package-toml}
7741 helps creating the file. You need to pass the outputs and the source of the
7742 package, it's name (the same as the @code{file-name} parameter), the package
7743 uuid, the package version, and a list of dependencies specified by their name
7747 @defvr {Scheme Variable} maven-build-system
7748 This variable is exported by @code{(guix build-system maven)}. It implements
7749 a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
7750 is a dependency and lifecycle management tool for Java. A user of Maven
7751 specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
7752 When Maven does not have one of the dependencies or plugins in its repository,
7753 it will download them and use them to build the package.
7755 The maven build system ensures that maven will not try to download any
7756 dependency by running in offline mode. Maven will fail if a dependency is
7757 missing. Before running Maven, the @file{pom.xml} (and subprojects) are
7758 modified to specify the version of dependencies and plugins that match the
7759 versions available in the guix build environment. Dependencies and plugins
7760 must be installed in the fake maven repository at @file{lib/m2}, and are
7761 symlinked into a proper repository before maven is run. Maven is instructed
7762 to use that repository for the build and installs built artifacts there.
7763 Changed files are copied to the @file{lib/m2} directory of the package output.
7765 You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
7766 or let the build system use the default @file{pom.xml} file in the sources.
7768 In case you need to specify a dependency's version manually, you can use the
7769 @code{#:local-packages} argument. It takes an association list where the key
7770 is the groupId of the package and its value is an association list where the
7771 key is the artifactId of the package and its value is the version you want to
7772 override in the @file{pom.xml}.
7774 Some packages use dependencies or plugins that are not useful at runtime nor
7775 at build time in Guix. You can alter the @file{pom.xml} file to remove them
7776 using the @code{#:exclude} argument. Its value is an association list where
7777 the key is the groupId of the plugin or dependency you want to remove, and
7778 the value is a list of artifactId you want to remove.
7780 You can override the default @code{jdk} and @code{maven} packages with the
7781 corresponding argument, @code{#:jdk} and @code{#:maven}.
7783 The @code{#:maven-plugins} argument is a list of maven plugins used during
7784 the build, with the same format as the @code{inputs} fields of the package
7785 declaration. Its default value is @code{(default-maven-plugins)} which is
7789 @defvr {Scheme Variable} minify-build-system
7790 This variable is exported by @code{(guix build-system minify)}. It
7791 implements a minification procedure for simple JavaScript packages.
7793 It adds @code{uglify-js} to the set of inputs and uses it to compress
7794 all JavaScript files in the @file{src} directory. A different minifier
7795 package can be specified with the @code{#:uglify-js} parameter, but it
7796 is expected that the package writes the minified code to the standard
7799 When the input JavaScript files are not all located in the @file{src}
7800 directory, the parameter @code{#:javascript-files} can be used to
7801 specify a list of file names to feed to the minifier.
7804 @defvr {Scheme Variable} ocaml-build-system
7805 This variable is exported by @code{(guix build-system ocaml)}. It implements
7806 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
7807 of choosing the correct set of commands to run for each package. OCaml
7808 packages can expect many different commands to be run. This build system will
7811 When the package has a @file{setup.ml} file present at the top-level, it will
7812 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
7813 @code{ocaml setup.ml -install}. The build system will assume that this file
7814 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
7815 care of setting the prefix and enabling tests if they are not disabled. You
7816 can pass configure and build flags with the @code{#:configure-flags} and
7817 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
7818 set of flags used to enable tests. The @code{#:use-make?} key can be used to
7819 bypass this system in the build and install phases.
7821 When the package has a @file{configure} file, it is assumed that it is a
7822 hand-made configure script that requires a different argument format than
7823 in the @code{gnu-build-system}. You can add more flags with the
7824 @code{#:configure-flags} key.
7826 When the package has a @file{Makefile} file (or @code{#:use-make?} is
7827 @code{#t}), it will be used and more flags can be passed to the build and
7828 install phases with the @code{#:make-flags} key.
7830 Finally, some packages do not have these files and use a somewhat standard
7831 location for its build system. In that case, the build system will run
7832 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
7833 providing the path to the required findlib module. Additional flags can
7834 be passed via the @code{#:build-flags} key. Install is taken care of by
7835 @command{opam-installer}. In this case, the @code{opam} package must
7836 be added to the @code{native-inputs} field of the package definition.
7838 Note that most OCaml packages assume they will be installed in the same
7839 directory as OCaml, which is not what we want in guix. In particular, they
7840 will install @file{.so} files in their module's directory, which is usually
7841 fine because it is in the OCaml compiler directory. In guix though, these
7842 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
7843 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
7844 @file{.so} libraries should be installed.
7847 @defvr {Scheme Variable} python-build-system
7848 This variable is exported by @code{(guix build-system python)}. It
7849 implements the more or less standard build procedure used by Python
7850 packages, which consists in running @code{python setup.py build} and
7851 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
7853 For packages that install stand-alone Python programs under @code{bin/},
7854 it takes care of wrapping these programs so that their @env{PYTHONPATH}
7855 environment variable points to all the Python libraries they depend on.
7857 Which Python package is used to perform the build can be specified with
7858 the @code{#:python} parameter. This is a useful way to force a package
7859 to be built for a specific version of the Python interpreter, which
7860 might be necessary if the package is only compatible with a single
7861 interpreter version.
7863 By default guix calls @code{setup.py} under control of
7864 @code{setuptools}, much like @command{pip} does. Some packages are not
7865 compatible with setuptools (and pip), thus you can disable this by
7866 setting the @code{#:use-setuptools?} parameter to @code{#f}.
7869 @defvr {Scheme Variable} perl-build-system
7870 This variable is exported by @code{(guix build-system perl)}. It
7871 implements the standard build procedure for Perl packages, which either
7872 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
7873 followed by @code{Build} and @code{Build install}; or in running
7874 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
7875 @code{make} and @code{make install}, depending on which of
7876 @code{Build.PL} or @code{Makefile.PL} is present in the package
7877 distribution. Preference is given to the former if both @code{Build.PL}
7878 and @code{Makefile.PL} exist in the package distribution. This
7879 preference can be reversed by specifying @code{#t} for the
7880 @code{#:make-maker?} parameter.
7882 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
7883 passes flags specified by the @code{#:make-maker-flags} or
7884 @code{#:module-build-flags} parameter, respectively.
7886 Which Perl package is used can be specified with @code{#:perl}.
7889 @defvr {Scheme Variable} renpy-build-system
7890 This variable is exported by @code{(guix build-system renpy)}. It implements
7891 the more or less standard build procedure used by Ren'py games, which consists
7892 of loading @code{#:game} once, thereby creating bytecode for it.
7894 It further creates a wrapper script in @code{bin/} and a desktop entry in
7895 @code{share/applications}, both of which can be used to launch the game.
7897 Which Ren'py package is used can be specified with @code{#:renpy}.
7898 Games can also be installed in outputs other than ``out'' by using
7902 @defvr {Scheme Variable} qt-build-system
7903 This variable is exported by @code{(guix build-system qt)}. It
7904 is intended for use with applications using Qt or KDE.
7906 This build system adds the following two phases to the ones defined by
7907 @code{cmake-build-system}:
7911 The phase @code{check-setup} prepares the environment for running
7912 the checks as commonly used by Qt test programs.
7913 For now this only sets some environment variables:
7914 @code{QT_QPA_PLATFORM=offscreen},
7915 @code{DBUS_FATAL_WARNINGS=0} and
7916 @code{CTEST_OUTPUT_ON_FAILURE=1}.
7918 This phase is added before the @code{check} phase.
7919 It's a separate phase to ease adjusting if necessary.
7922 The phase @code{qt-wrap}
7923 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
7924 and output. In case some path is found, all programs in the output's
7925 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
7926 are wrapped in scripts defining the necessary environment variables.
7928 It is possible to exclude specific package outputs from that wrapping process
7929 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
7930 This is useful when an output is known not to contain any Qt binaries, and
7931 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
7934 This phase is added after the @code{install} phase.
7938 @defvr {Scheme Variable} r-build-system
7939 This variable is exported by @code{(guix build-system r)}. It
7940 implements the build procedure used by @uref{https://r-project.org, R}
7941 packages, which essentially is little more than running @samp{R CMD
7942 INSTALL --library=/gnu/store/@dots{}} in an environment where
7943 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
7944 run after installation using the R function
7945 @code{tools::testInstalledPackage}.
7948 @defvr {Scheme Variable} rakudo-build-system
7949 This variable is exported by @code{(guix build-system rakudo)}. It
7950 implements the build procedure used by @uref{https://rakudo.org/,
7951 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
7952 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
7953 installs the binaries, library files and the resources, as well as wrap
7954 the files under the @code{bin/} directory. Tests can be skipped by
7955 passing @code{#f} to the @code{tests?} parameter.
7957 Which rakudo package is used can be specified with @code{rakudo}.
7958 Which perl6-tap-harness package used for the tests can be specified with
7959 @code{#:prove6} or removed by passing @code{#f} to the
7960 @code{with-prove6?} parameter.
7961 Which perl6-zef package used for tests and installing can be specified
7962 with @code{#:zef} or removed by passing @code{#f} to the
7963 @code{with-zef?} parameter.
7966 @defvr {Scheme Variable} texlive-build-system
7967 This variable is exported by @code{(guix build-system texlive)}. It is
7968 used to build TeX packages in batch mode with a specified engine. The
7969 build system sets the @env{TEXINPUTS} variable to find all TeX source
7970 files in the inputs.
7972 By default it runs @code{luatex} on all files ending on @code{ins}. A
7973 different engine and format can be specified with the
7974 @code{#:tex-format} argument. Different build targets can be specified
7975 with the @code{#:build-targets} argument, which expects a list of file
7976 names. The build system adds only @code{texlive-bin} and
7977 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
7978 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
7979 and @code{#:texlive-latex-base}, respectively.
7981 The @code{#:tex-directory} parameter tells the build system where to
7982 install the built files under the texmf tree.
7985 @defvr {Scheme Variable} ruby-build-system
7986 This variable is exported by @code{(guix build-system ruby)}. It
7987 implements the RubyGems build procedure used by Ruby packages, which
7988 involves running @code{gem build} followed by @code{gem install}.
7990 The @code{source} field of a package that uses this build system
7991 typically references a gem archive, since this is the format that Ruby
7992 developers use when releasing their software. The build system unpacks
7993 the gem archive, potentially patches the source, runs the test suite,
7994 repackages the gem, and installs it. Additionally, directories and
7995 tarballs may be referenced to allow building unreleased gems from Git or
7996 a traditional source release tarball.
7998 Which Ruby package is used can be specified with the @code{#:ruby}
7999 parameter. A list of additional flags to be passed to the @command{gem}
8000 command can be specified with the @code{#:gem-flags} parameter.
8003 @defvr {Scheme Variable} waf-build-system
8004 This variable is exported by @code{(guix build-system waf)}. It
8005 implements a build procedure around the @code{waf} script. The common
8006 phases---@code{configure}, @code{build}, and @code{install}---are
8007 implemented by passing their names as arguments to the @code{waf}
8010 The @code{waf} script is executed by the Python interpreter. Which
8011 Python package is used to run the script can be specified with the
8012 @code{#:python} parameter.
8015 @defvr {Scheme Variable} scons-build-system
8016 This variable is exported by @code{(guix build-system scons)}. It
8017 implements the build procedure used by the SCons software construction
8018 tool. This build system runs @code{scons} to build the package,
8019 @code{scons test} to run tests, and then @code{scons install} to install
8022 Additional flags to be passed to @code{scons} can be specified with the
8023 @code{#:scons-flags} parameter. The default build and install targets
8024 can be overridden with @code{#:build-targets} and
8025 @code{#:install-targets} respectively. The version of Python used to
8026 run SCons can be specified by selecting the appropriate SCons package
8027 with the @code{#:scons} parameter.
8030 @defvr {Scheme Variable} haskell-build-system
8031 This variable is exported by @code{(guix build-system haskell)}. It
8032 implements the Cabal build procedure used by Haskell packages, which
8033 involves running @code{runhaskell Setup.hs configure
8034 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
8035 Instead of installing the package by running @code{runhaskell Setup.hs
8036 install}, to avoid trying to register libraries in the read-only
8037 compiler store directory, the build system uses @code{runhaskell
8038 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
8039 addition, the build system generates the package documentation by
8040 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
8041 is passed. Optional Haddock parameters can be passed with the help of
8042 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
8043 not found, the build system looks for @code{Setup.lhs} instead.
8045 Which Haskell compiler is used can be specified with the @code{#:haskell}
8046 parameter which defaults to @code{ghc}.
8049 @defvr {Scheme Variable} dub-build-system
8050 This variable is exported by @code{(guix build-system dub)}. It
8051 implements the Dub build procedure used by D packages, which
8052 involves running @code{dub build} and @code{dub run}.
8053 Installation is done by copying the files manually.
8055 Which D compiler is used can be specified with the @code{#:ldc}
8056 parameter which defaults to @code{ldc}.
8059 @anchor{emacs-build-system}
8060 @defvr {Scheme Variable} emacs-build-system
8061 This variable is exported by @code{(guix build-system emacs)}. It
8062 implements an installation procedure similar to the packaging system
8063 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
8065 It first creates the @code{@code{package}-autoloads.el} file, then it
8066 byte compiles all Emacs Lisp files. Differently from the Emacs
8067 packaging system, the Info documentation files are moved to the standard
8068 documentation directory and the @file{dir} file is deleted. The Elisp
8069 package files are installed directly under @file{share/emacs/site-lisp}.
8072 @defvr {Scheme Variable} font-build-system
8073 This variable is exported by @code{(guix build-system font)}. It
8074 implements an installation procedure for font packages where upstream
8075 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
8076 need to be copied into place. It copies font files to standard
8077 locations in the output directory.
8080 @defvr {Scheme Variable} meson-build-system
8081 This variable is exported by @code{(guix build-system meson)}. It
8082 implements the build procedure for packages that use
8083 @url{https://mesonbuild.com, Meson} as their build system.
8085 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
8086 of inputs, and they can be changed with the parameters @code{#:meson}
8087 and @code{#:ninja} if needed. The default Meson is
8088 @code{meson-for-build}, which is special because it doesn't clear the
8089 @code{RUNPATH} of binaries and libraries when they are installed.
8091 This build system is an extension of @code{gnu-build-system}, but with the
8092 following phases changed to some specific for Meson:
8097 The phase runs @code{meson} with the flags specified in
8098 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
8099 @code{debugoptimized} unless something else is specified in
8100 @code{#:build-type}.
8103 The phase runs @code{ninja} to build the package in parallel by default, but
8104 this can be changed with @code{#:parallel-build?}.
8107 The phase runs @code{ninja} with the target specified in @code{#:test-target},
8108 which is @code{"test"} by default.
8111 The phase runs @code{ninja install} and can not be changed.
8114 Apart from that, the build system also adds the following phases:
8119 This phase ensures that all binaries can find the libraries they need.
8120 It searches for required libraries in subdirectories of the package being
8121 built, and adds those to @code{RUNPATH} where needed. It also removes
8122 references to libraries left over from the build phase by
8123 @code{meson-for-build}, such as test dependencies, that aren't actually
8124 required for the program to run.
8126 @item glib-or-gtk-wrap
8127 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
8128 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
8130 @item glib-or-gtk-compile-schemas
8131 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
8132 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
8136 @defvr {Scheme Variable} linux-module-build-system
8137 @code{linux-module-build-system} allows building Linux kernel modules.
8139 @cindex build phases
8140 This build system is an extension of @code{gnu-build-system}, but with the
8141 following phases changed:
8146 This phase configures the environment so that the Linux kernel's Makefile
8147 can be used to build the external kernel module.
8150 This phase uses the Linux kernel's Makefile in order to build the external
8154 This phase uses the Linux kernel's Makefile in order to install the external
8158 It is possible and useful to specify the Linux kernel to use for building
8159 the module (in the @code{arguments} form of a package using the
8160 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
8163 @defvr {Scheme Variable} node-build-system
8164 This variable is exported by @code{(guix build-system node)}. It
8165 implements the build procedure used by @uref{https://nodejs.org,
8166 Node.js}, which implements an approximation of the @code{npm install}
8167 command, followed by an @code{npm test} command.
8169 Which Node.js package is used to interpret the @code{npm} commands can
8170 be specified with the @code{#:node} parameter which defaults to
8174 Lastly, for packages that do not need anything as sophisticated, a
8175 ``trivial'' build system is provided. It is trivial in the sense that
8176 it provides basically no support: it does not pull any implicit inputs,
8177 and does not have a notion of build phases.
8179 @defvr {Scheme Variable} trivial-build-system
8180 This variable is exported by @code{(guix build-system trivial)}.
8182 This build system requires a @code{#:builder} argument. This argument
8183 must be a Scheme expression that builds the package output(s)---as
8184 with @code{build-expression->derivation} (@pxref{Derivations,
8185 @code{build-expression->derivation}}).
8189 @section Build Phases
8191 @cindex build phases, for packages
8192 Almost all package build systems implement a notion @dfn{build phases}:
8193 a sequence of actions that the build system executes, when you build the
8194 package, leading to the installed byproducts in the store. A notable
8195 exception is the ``bare-bones'' @code{trivial-build-system}
8196 (@pxref{Build Systems}).
8198 As discussed in the previous section, those build systems provide a
8199 standard list of phases. For @code{gnu-build-system}, the standard
8200 phases include an @code{unpack} phase to unpack the source code tarball,
8201 a @command{configure} phase to run @code{./configure}, a @code{build}
8202 phase to run @command{make}, and (among others) an @code{install} phase
8203 to run @command{make install}; @pxref{Build Systems}, for a more
8204 detailed view of these phases. Likewise, @code{cmake-build-system}
8205 inherits these phases, but its @code{configure} phase runs
8206 @command{cmake} instead of @command{./configure}. Other build systems,
8207 such as @code{python-build-system}, have a wholly different list of
8208 standard phases. All this code runs on the @dfn{build side}: it is
8209 evaluated when you actually build the package, in a dedicated build
8210 process spawned by the build daemon (@pxref{Invoking guix-daemon}).
8212 Build phases are represented as association lists or ``alists''
8213 (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
8214 each key is a symbol for the name of the phase and the associated value
8215 is a procedure that accepts an arbitrary number of arguments. By
8216 convention, those procedures receive information about the build in the
8217 form of @dfn{keyword parameters}, which they can use or ignore.
8219 For example, here is how @code{(guix build gnu-build-system)} defines
8220 @code{%standard-phases}, the variable holding its alist of build
8221 phases@footnote{We present a simplified view of those build phases, but
8222 do take a look at @code{(guix build gnu-build-system)} to see all the
8226 ;; The build phases of 'gnu-build-system'.
8228 (define* (unpack #:key source #:allow-other-keys)
8229 ;; Extract the source tarball.
8230 (invoke "tar" "xvf" source))
8232 (define* (configure #:key outputs #:allow-other-keys)
8233 ;; Run the 'configure' script. Install to output "out".
8234 (let ((out (assoc-ref outputs "out")))
8235 (invoke "./configure"
8236 (string-append "--prefix=" out))))
8238 (define* (build #:allow-other-keys)
8242 (define* (check #:key (test-target "check") (tests? #true)
8244 ;; Run the test suite.
8246 (invoke "make" test-target)
8247 (display "test suite not run\n")))
8249 (define* (install #:allow-other-keys)
8250 ;; Install files to the prefix 'configure' specified.
8251 (invoke "make" "install"))
8253 (define %standard-phases
8254 ;; The list of standard phases (quite a few are omitted
8255 ;; for brevity). Each element is a symbol/procedure pair.
8256 (list (cons 'unpack unpack)
8257 (cons 'configure configure)
8260 (cons 'install install)))
8263 This shows how @code{%standard-phases} is defined as a list of
8264 symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
8265 Manual}). The first pair associates the @code{unpack} procedure with
8266 the @code{unpack} symbol---a name; the second pair defines the
8267 @code{configure} phase similarly, and so on. When building a package
8268 that uses @code{gnu-build-system} with its default list of phases, those
8269 phases are executed sequentially. You can see the name of each phase
8270 started and completed in the build log of packages that you build.
8272 Let's now look at the procedures themselves. Each one is defined with
8273 @code{define*}: @code{#:key} lists keyword parameters the procedure
8274 accepts, possibly with a default value, and @code{#:allow-other-keys}
8275 specifies that other keyword parameters are ignored (@pxref{Optional
8276 Arguments,,, guile, GNU Guile Reference Manual}).
8278 The @code{unpack} procedure honors the @code{source} parameter, which
8279 the build system uses to pass the file name of the source tarball (or
8280 version control checkout), and it ignores other parameters. The
8281 @code{configure} phase only cares about the @code{outputs} parameter, an
8282 alist mapping package output names to their store file name
8283 (@pxref{Packages with Multiple Outputs}). It extracts the file name of
8284 for @code{out}, the default output, and passes it to
8285 @command{./configure} as the installation prefix, meaning that
8286 @command{make install} will eventually copy all the files in that
8287 directory (@pxref{Configuration, configuration and makefile
8288 conventions,, standards, GNU Coding Standards}). @code{build} and
8289 @code{install} ignore all their arguments. @code{check} honors the
8290 @code{test-target} argument, which specifies the name of the Makefile
8291 target to run tests; it prints a message and skips tests when
8292 @code{tests?} is false.
8294 @cindex build phases, customizing
8295 The list of phases used for a particular package can be changed with the
8296 @code{#:phases} parameter of the build system. Changing the set of
8297 build phases boils down to building a new alist of phases based on the
8298 @code{%standard-phases} alist described above. This can be done with
8299 standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
8300 Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
8301 more convenient to do so with @code{modify-phases} (@pxref{Build
8302 Utilities, @code{modify-phases}}).
8304 Here is an example of a package definition that removes the
8305 @code{configure} phase of @code{%standard-phases} and inserts a new
8306 phase before the @code{build} phase, called
8307 @code{set-prefix-in-makefile}:
8310 (define-public example
8313 ;; other fields omitted
8314 (build-system gnu-build-system)
8316 '(#:phases (modify-phases %standard-phases
8318 (add-before 'build 'set-prefix-in-makefile
8319 (lambda* (#:key outputs #:allow-other-keys)
8320 ;; Modify the makefile so that its
8321 ;; 'PREFIX' variable points to "out".
8322 (let ((out (assoc-ref outputs "out")))
8323 (substitute* "Makefile"
8325 (string-append "PREFIX = "
8330 The new phase that is inserted is written as an anonymous procedure,
8331 introduced with @code{lambda*}; it honors the @code{outputs} parameter
8332 we have seen before. @xref{Build Utilities}, for more about the helpers
8333 used by this phase, and for more examples of @code{modify-phases}.
8335 @cindex code staging
8336 @cindex staging, of code
8337 Keep in mind that build phases are code evaluated at the time the
8338 package is actually built. This explains why the whole
8339 @code{modify-phases} expression above is quoted (it comes after the
8340 @code{'} or apostrophe): it is @dfn{staged} for later execution.
8341 @xref{G-Expressions}, for an explanation of code staging and the
8342 @dfn{code strata} involved.
8344 @node Build Utilities
8345 @section Build Utilities
8347 As soon as you start writing non-trivial package definitions
8348 (@pxref{Defining Packages}) or other build actions
8349 (@pxref{G-Expressions}), you will likely start looking for helpers for
8350 ``shell-like'' actions---creating directories, copying and deleting
8351 files recursively, manipulating build phases, and so on. The
8352 @code{(guix build utils)} module provides such utility procedures.
8354 Most build systems load @code{(guix build utils)} (@pxref{Build
8355 Systems}). Thus, when writing custom build phases for your package
8356 definitions, you can usually assume those procedures are in scope.
8358 When writing G-expressions, you can import @code{(guix build utils)} on
8359 the ``build side'' using @code{with-imported-modules} and then put it in
8360 scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
8361 guile, GNU Guile Reference Manual}):
8364 (with-imported-modules '((guix build utils)) ;import it
8365 (computed-file "empty-tree"
8368 (use-modules (guix build utils))
8370 ;; Happily use its 'mkdir-p' procedure.
8371 (mkdir-p (string-append #$output "/a/b/c")))))
8374 The remainder of this section is the reference for most of the utility
8375 procedures provided by @code{(guix build utils)}.
8377 @c TODO Document what's missing.
8379 @subsection Dealing with Store File Names
8381 This section documents procedures that deal with store file names.
8383 @deffn {Scheme Procedure} %store-directory
8384 Return the directory name of the store.
8387 @deffn {Scheme Procedure} store-file-name? @var{file}
8388 Return true if @var{file} is in the store.
8391 @deffn {Scheme Procedure} strip-store-file-name @var{file}
8392 Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
8393 The result is typically a @code{"@var{package}-@var{version}"} string.
8396 @deffn {Scheme Procedure} package-name->name+version @var{name}
8397 Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
8398 values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
8399 unavailable, @var{name} and @code{#f} are returned. The first hyphen
8400 followed by a digit is considered to introduce the version part.
8403 @subsection File Types
8405 The procedures below deal with files and file types.
8407 @deffn {Scheme Procedure} directory-exists? @var{dir}
8408 Return @code{#t} if @var{dir} exists and is a directory.
8411 @deffn {Scheme Procedure} executable-file? @var{file}
8412 Return @code{#t} if @var{file} exists and is executable.
8415 @deffn {Scheme Procedure} symbolic-link? @var{file}
8416 Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
8419 @deffn {Scheme Procedure} elf-file? @var{file}
8420 @deffnx {Scheme Procedure} ar-file? @var{file}
8421 @deffnx {Scheme Procedure} gzip-file? @var{file}
8422 Return @code{#t} if @var{file} is, respectively, an ELF file, an
8423 @code{ar} archive (such as a @file{.a} static library), or a gzip file.
8426 @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
8427 If @var{file} is a gzip file, reset its embedded timestamp (as with
8428 @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
8429 When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
8432 @subsection File Manipulation
8434 The following procedures and macros help create, modify, and delete
8435 files. They provide functionality comparable to common shell utilities
8436 such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
8437 @command{sed}. They complement Guile's extensive, but low-level, file
8438 system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
8440 @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
8441 Run @var{body} with @var{directory} as the process's current directory.
8443 Essentially, this macro changes the current directory to @var{directory}
8444 before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
8445 guile, GNU Guile Reference Manual}). It changes back to the initial
8446 directory when the dynamic extent of @var{body} is left, be it @i{via}
8447 normal procedure return or @i{via} a non-local exit such as an
8451 @deffn {Scheme Procedure} mkdir-p @var{dir}
8452 Create directory @var{dir} and all its ancestors.
8455 @deffn {Scheme Procedure} install-file @var{file} @var{directory}
8456 Create @var{directory} if it does not exist and copy @var{file} in there
8457 under the same name.
8460 @deffn {Scheme Procedure} make-file-writable @var{file}
8461 Make @var{file} writable for its owner.
8464 @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
8465 [#:log (current-output-port)] [#:follow-symlinks? #f] [#:keep-mtime? #f]
8466 Copy @var{source} directory to @var{destination}. Follow symlinks if
8467 @var{follow-symlinks?} is true; otherwise, just preserve them. When
8468 @var{keep-mtime?} is true, keep the modification time of the files in
8469 @var{source} on those of @var{destination}. Write verbose output to the
8473 @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
8474 [#:follow-mounts? #f]
8475 Delete @var{dir} recursively, like @command{rm -rf}, without following
8476 symlinks. Don't follow mount points either, unless @var{follow-mounts?}
8477 is true. Report but ignore errors.
8480 @deffn {Scheme Syntax} substitute* @var{file} @
8481 ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
8482 Substitute @var{regexp} in @var{file} by the string returned by
8483 @var{body}. @var{body} is evaluated with each @var{match-var} bound to
8484 the corresponding positional regexp sub-expression. For example:
8490 (("foo([a-z]+)bar(.*)$" all letters end)
8491 (string-append "baz" letter end)))
8494 Here, anytime a line of @var{file} contains @code{hello}, it is replaced
8495 by @code{good morning}. Anytime a line of @var{file} matches the second
8496 regexp, @code{all} is bound to the complete match, @code{letters} is bound
8497 to the first sub-expression, and @code{end} is bound to the last one.
8499 When one of the @var{match-var} is @code{_}, no variable is bound to the
8500 corresponding match substring.
8502 Alternatively, @var{file} may be a list of file names, in which case
8503 they are all subject to the substitutions.
8505 Be careful about using @code{$} to match the end of a line; by itself it
8506 won't match the terminating newline of a line.
8509 @subsection File Search
8511 @cindex file, searching
8512 This section documents procedures to search and filter files.
8514 @deffn {Scheme Procedure} file-name-predicate @var{regexp}
8515 Return a predicate that returns true when passed a file name whose base
8516 name matches @var{regexp}.
8519 @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
8520 [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
8521 Return the lexicographically sorted list of files under @var{dir} for
8522 which @var{pred} returns true. @var{pred} is passed two arguments: the
8523 absolute file name, and its stat buffer; the default predicate always
8524 returns true. @var{pred} can also be a regular expression, in which
8525 case it is equivalent to @code{(file-name-predicate @var{pred})}.
8526 @var{stat} is used to obtain file information; using @code{lstat} means
8527 that symlinks are not followed. If @var{directories?} is true, then
8528 directories will also be included. If @var{fail-on-error?} is true,
8529 raise an exception upon error.
8532 Here are a few examples where we assume that the current directory is
8533 the root of the Guix source tree:
8536 ;; List all the regular files in the current directory.
8538 @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
8540 ;; List all the .scm files under gnu/services.
8541 (find-files "gnu/services" "\\.scm$")
8542 @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
8544 ;; List ar files in the current directory.
8545 (find-files "." (lambda (file stat) (ar-file? file)))
8546 @result{} ("./libformat.a" "./libstore.a" @dots{})
8549 @deffn {Scheme Procedure} which @var{program}
8550 Return the complete file name for @var{program} as found in
8551 @code{$PATH}, or @code{#f} if @var{program} could not be found.
8554 @subsection Build Phases
8556 @cindex build phases
8557 The @code{(guix build utils)} also contains tools to manipulate build
8558 phases as used by build systems (@pxref{Build Systems}). Build phases
8559 are represented as association lists or ``alists'' (@pxref{Association
8560 Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
8561 naming the phase and the associated value is a procedure (@pxref{Build
8564 Guile core and the @code{(srfi srfi-1)} module both provide tools to
8565 manipulate alists. The @code{(guix build utils)} module complements
8566 those with tools written with build phases in mind.
8568 @cindex build phases, modifying
8569 @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
8570 Modify @var{phases} sequentially as per each @var{clause}, which may
8571 have one of the following forms:
8574 (delete @var{old-phase-name})
8575 (replace @var{old-phase-name} @var{new-phase})
8576 (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
8577 (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
8580 Where every @var{phase-name} above is an expression evaluating to a
8581 symbol, and @var{new-phase} an expression evaluating to a procedure.
8584 The example below is taken from the definition of the @code{grep}
8585 package. It adds a phase to run after the @code{install} phase, called
8586 @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
8587 is for anonymous procedures) that takes a @code{#:outputs} keyword
8588 argument and ignores extra keyword arguments (@pxref{Optional
8589 Arguments,,, guile, GNU Guile Reference Manual}, for more on
8590 @code{lambda*} and optional and keyword arguments.) The phase uses
8591 @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
8592 scripts so that they refer to @code{grep} by its absolute file name:
8595 (modify-phases %standard-phases
8596 (add-after 'install 'fix-egrep-and-fgrep
8597 ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
8598 ;; absolute file name instead of searching for it in $PATH.
8599 (lambda* (#:key outputs #:allow-other-keys)
8600 (let* ((out (assoc-ref outputs "out"))
8601 (bin (string-append out "/bin")))
8602 (substitute* (list (string-append bin "/egrep")
8603 (string-append bin "/fgrep"))
8605 (string-append "exec " bin "/grep")))
8609 In the example below, phases are modified in two ways: the standard
8610 @code{configure} phase is deleted, presumably because the package does
8611 not have a @file{configure} script or anything similar, and the default
8612 @code{install} phase is replaced by one that manually copies the
8613 executable files to be installed:
8616 (modify-phases %standard-phases
8617 (delete 'configure) ;no 'configure' script
8619 (lambda* (#:key outputs #:allow-other-keys)
8620 ;; The package's Makefile doesn't provide an "install"
8621 ;; rule so do it by ourselves.
8622 (let ((bin (string-append (assoc-ref outputs "out")
8624 (install-file "footswitch" bin)
8625 (install-file "scythe" bin)
8629 @c TODO: Add more examples.
8638 Conceptually, the @dfn{store} is the place where derivations that have
8639 been built successfully are stored---by default, @file{/gnu/store}.
8640 Sub-directories in the store are referred to as @dfn{store items} or
8641 sometimes @dfn{store paths}. The store has an associated database that
8642 contains information such as the store paths referred to by each store
8643 path, and the list of @emph{valid} store items---results of successful
8644 builds. This database resides in @file{@var{localstatedir}/guix/db},
8645 where @var{localstatedir} is the state directory specified @i{via}
8646 @option{--localstatedir} at configure time, usually @file{/var}.
8648 The store is @emph{always} accessed by the daemon on behalf of its clients
8649 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
8650 connect to the daemon over a Unix-domain socket, send requests to it,
8651 and read the result---these are remote procedure calls, or RPCs.
8654 Users must @emph{never} modify files under @file{/gnu/store} directly.
8655 This would lead to inconsistencies and break the immutability
8656 assumptions of Guix's functional model (@pxref{Introduction}).
8658 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
8659 how to check the integrity of the store and attempt recovery from
8660 accidental modifications.
8663 The @code{(guix store)} module provides procedures to connect to the
8664 daemon, and to perform RPCs. These are described below. By default,
8665 @code{open-connection}, and thus all the @command{guix} commands,
8666 connect to the local daemon or to the URI specified by the
8667 @env{GUIX_DAEMON_SOCKET} environment variable.
8669 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
8670 When set, the value of this variable should be a file name or a URI
8671 designating the daemon endpoint. When it is a file name, it denotes a
8672 Unix-domain socket to connect to. In addition to file names, the
8673 supported URI schemes are:
8678 These are for Unix-domain sockets.
8679 @code{file:///var/guix/daemon-socket/socket} is equivalent to
8680 @file{/var/guix/daemon-socket/socket}.
8683 @cindex daemon, remote access
8684 @cindex remote access to the daemon
8685 @cindex daemon, cluster setup
8686 @cindex clusters, daemon setup
8687 These URIs denote connections over TCP/IP, without encryption nor
8688 authentication of the remote host. The URI must specify the host name
8689 and optionally a port number (by default port 44146 is used):
8692 guix://master.guix.example.org:1234
8695 This setup is suitable on local networks, such as clusters, where only
8696 trusted nodes may connect to the build daemon at
8697 @code{master.guix.example.org}.
8699 The @option{--listen} option of @command{guix-daemon} can be used to
8700 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
8701 @option{--listen}}).
8704 @cindex SSH access to build daemons
8705 These URIs allow you to connect to a remote daemon over SSH@. This
8706 feature requires Guile-SSH (@pxref{Requirements}) and a working
8707 @command{guile} binary in @env{PATH} on the destination machine. It
8708 supports public key and GSSAPI authentication. A typical URL might look
8712 ssh://charlie@@guix.example.org:22
8715 As for @command{guix copy}, the usual OpenSSH client configuration files
8716 are honored (@pxref{Invoking guix copy}).
8719 Additional URI schemes may be supported in the future.
8721 @c XXX: Remove this note when the protocol incurs fewer round trips
8722 @c and when (guix derivations) no longer relies on file system access.
8724 The ability to connect to remote build daemons is considered
8725 experimental as of @value{VERSION}. Please get in touch with us to
8726 share any problems or suggestions you may have (@pxref{Contributing}).
8730 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
8731 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
8732 @var{reserve-space?} is true, instruct it to reserve a little bit of
8733 extra space on the file system so that the garbage collector can still
8734 operate should the disk become full. Return a server object.
8736 @var{file} defaults to @code{%default-socket-path}, which is the normal
8737 location given the options that were passed to @command{configure}.
8740 @deffn {Scheme Procedure} close-connection @var{server}
8741 Close the connection to @var{server}.
8744 @defvr {Scheme Variable} current-build-output-port
8745 This variable is bound to a SRFI-39 parameter, which refers to the port
8746 where build and error logs sent by the daemon should be written.
8749 Procedures that make RPCs all take a server object as their first
8752 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
8753 @cindex invalid store items
8754 Return @code{#t} when @var{path} designates a valid store item and
8755 @code{#f} otherwise (an invalid item may exist on disk but still be
8756 invalid, for instance because it is the result of an aborted or failed
8759 A @code{&store-protocol-error} condition is raised if @var{path} is not
8760 prefixed by the store directory (@file{/gnu/store}).
8763 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
8764 Add @var{text} under file @var{name} in the store, and return its store
8765 path. @var{references} is the list of store paths referred to by the
8766 resulting store path.
8769 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
8771 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
8772 file names, or derivation/output pairs, using the specified
8773 @var{mode}---@code{(build-mode normal)} by default.
8776 Note that the @code{(guix monads)} module provides a monad as well as
8777 monadic versions of the above procedures, with the goal of making it
8778 more convenient to work with code that accesses the store (@pxref{The
8782 @i{This section is currently incomplete.}
8785 @section Derivations
8788 Low-level build actions and the environment in which they are performed
8789 are represented by @dfn{derivations}. A derivation contains the
8790 following pieces of information:
8794 The outputs of the derivation---derivations produce at least one file or
8795 directory in the store, but may produce more.
8798 @cindex build-time dependencies
8799 @cindex dependencies, build-time
8800 The inputs of the derivations---i.e., its build-time dependencies---which may
8801 be other derivations or plain files in the store (patches, build scripts,
8805 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
8808 The file name of a build script in the store, along with the arguments
8812 A list of environment variables to be defined.
8816 @cindex derivation path
8817 Derivations allow clients of the daemon to communicate build actions to
8818 the store. They exist in two forms: as an in-memory representation,
8819 both on the client- and daemon-side, and as files in the store whose
8820 name end in @file{.drv}---these files are referred to as @dfn{derivation
8821 paths}. Derivations paths can be passed to the @code{build-derivations}
8822 procedure to perform the build actions they prescribe (@pxref{The
8825 @cindex fixed-output derivations
8826 Operations such as file downloads and version-control checkouts for
8827 which the expected content hash is known in advance are modeled as
8828 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
8829 of a fixed-output derivation are independent of its inputs---e.g., a
8830 source code download produces the same result regardless of the download
8831 method and tools being used.
8834 @cindex run-time dependencies
8835 @cindex dependencies, run-time
8836 The outputs of derivations---i.e., the build results---have a set of
8837 @dfn{references}, as reported by the @code{references} RPC or the
8838 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
8839 are the set of run-time dependencies of the build results. References are a
8840 subset of the inputs of the derivation; this subset is automatically computed
8841 by the build daemon by scanning all the files in the outputs.
8843 The @code{(guix derivations)} module provides a representation of
8844 derivations as Scheme objects, along with procedures to create and
8845 otherwise manipulate derivations. The lowest-level primitive to create
8846 a derivation is the @code{derivation} procedure:
8848 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
8849 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
8850 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
8851 [#:system (%current-system)] [#:references-graphs #f] @
8852 [#:allowed-references #f] [#:disallowed-references #f] @
8853 [#:leaked-env-vars #f] [#:local-build? #f] @
8854 [#:substitutable? #t] [#:properties '()]
8855 Build a derivation with the given arguments, and return the resulting
8856 @code{<derivation>} object.
8858 When @var{hash} and @var{hash-algo} are given, a
8859 @dfn{fixed-output derivation} is created---i.e., one whose result is
8860 known in advance, such as a file download. If, in addition,
8861 @var{recursive?} is true, then that fixed output may be an executable
8862 file or a directory and @var{hash} must be the hash of an archive
8863 containing this output.
8865 When @var{references-graphs} is true, it must be a list of file
8866 name/store path pairs. In that case, the reference graph of each store
8867 path is exported in the build environment in the corresponding file, in
8868 a simple text format.
8870 When @var{allowed-references} is true, it must be a list of store items
8871 or outputs that the derivation's output may refer to. Likewise,
8872 @var{disallowed-references}, if true, must be a list of things the
8873 outputs may @emph{not} refer to.
8875 When @var{leaked-env-vars} is true, it must be a list of strings
8876 denoting environment variables that are allowed to ``leak'' from the
8877 daemon's environment to the build environment. This is only applicable
8878 to fixed-output derivations---i.e., when @var{hash} is true. The main
8879 use is to allow variables such as @code{http_proxy} to be passed to
8880 derivations that download files.
8882 When @var{local-build?} is true, declare that the derivation is not a
8883 good candidate for offloading and should rather be built locally
8884 (@pxref{Daemon Offload Setup}). This is the case for small derivations
8885 where the costs of data transfers would outweigh the benefits.
8887 When @var{substitutable?} is false, declare that substitutes of the
8888 derivation's output should not be used (@pxref{Substitutes}). This is
8889 useful, for instance, when building packages that capture details of the
8890 host CPU instruction set.
8892 @var{properties} must be an association list describing ``properties'' of the
8893 derivation. It is kept as-is, uninterpreted, in the derivation.
8897 Here's an example with a shell script as its builder, assuming
8898 @var{store} is an open connection to the daemon, and @var{bash} points
8899 to a Bash executable in the store:
8902 (use-modules (guix utils)
8906 (let ((builder ; add the Bash script to the store
8907 (add-text-to-store store "my-builder.sh"
8908 "echo hello world > $out\n" '())))
8909 (derivation store "foo"
8910 bash `("-e" ,builder)
8911 #:inputs `((,bash) (,builder))
8912 #:env-vars '(("HOME" . "/homeless"))))
8913 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
8916 As can be guessed, this primitive is cumbersome to use directly. A
8917 better approach is to write build scripts in Scheme, of course! The
8918 best course of action for that is to write the build code as a
8919 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
8920 information, @pxref{G-Expressions}.
8922 Once upon a time, @code{gexp->derivation} did not exist and constructing
8923 derivations with build code written in Scheme was achieved with
8924 @code{build-expression->derivation}, documented below. This procedure
8925 is now deprecated in favor of the much nicer @code{gexp->derivation}.
8927 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
8928 @var{name} @var{exp} @
8929 [#:system (%current-system)] [#:inputs '()] @
8930 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
8931 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
8932 [#:references-graphs #f] [#:allowed-references #f] @
8933 [#:disallowed-references #f] @
8934 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
8935 Return a derivation that executes Scheme expression @var{exp} as a
8936 builder for derivation @var{name}. @var{inputs} must be a list of
8937 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
8938 @code{"out"} is assumed. @var{modules} is a list of names of Guile
8939 modules from the current search path to be copied in the store,
8940 compiled, and made available in the load path during the execution of
8941 @var{exp}---e.g., @code{((guix build utils) (guix build
8942 gnu-build-system))}.
8944 @var{exp} is evaluated in an environment where @code{%outputs} is bound
8945 to a list of output/path pairs, and where @code{%build-inputs} is bound
8946 to a list of string/output-path pairs made from @var{inputs}.
8947 Optionally, @var{env-vars} is a list of string pairs specifying the name
8948 and value of environment variables visible to the builder. The builder
8949 terminates by passing the result of @var{exp} to @code{exit}; thus, when
8950 @var{exp} returns @code{#f}, the build is considered to have failed.
8952 @var{exp} is built using @var{guile-for-build} (a derivation). When
8953 @var{guile-for-build} is omitted or is @code{#f}, the value of the
8954 @code{%guile-for-build} fluid is used instead.
8956 See the @code{derivation} procedure for the meaning of
8957 @var{references-graphs}, @var{allowed-references},
8958 @var{disallowed-references}, @var{local-build?}, and
8959 @var{substitutable?}.
8963 Here's an example of a single-output derivation that creates a directory
8964 containing one file:
8967 (let ((builder '(let ((out (assoc-ref %outputs "out")))
8968 (mkdir out) ; create /gnu/store/@dots{}-goo
8969 (call-with-output-file (string-append out "/test")
8971 (display '(hello guix) p))))))
8972 (build-expression->derivation store "goo" builder))
8974 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
8978 @node The Store Monad
8979 @section The Store Monad
8983 The procedures that operate on the store described in the previous
8984 sections all take an open connection to the build daemon as their first
8985 argument. Although the underlying model is functional, they either have
8986 side effects or depend on the current state of the store.
8988 The former is inconvenient: the connection to the build daemon has to be
8989 carried around in all those functions, making it impossible to compose
8990 functions that do not take that parameter with functions that do. The
8991 latter can be problematic: since store operations have side effects
8992 and/or depend on external state, they have to be properly sequenced.
8994 @cindex monadic values
8995 @cindex monadic functions
8996 This is where the @code{(guix monads)} module comes in. This module
8997 provides a framework for working with @dfn{monads}, and a particularly
8998 useful monad for our uses, the @dfn{store monad}. Monads are a
8999 construct that allows two things: associating ``context'' with values
9000 (in our case, the context is the store), and building sequences of
9001 computations (here computations include accesses to the store). Values
9002 in a monad---values that carry this additional context---are called
9003 @dfn{monadic values}; procedures that return such values are called
9004 @dfn{monadic procedures}.
9006 Consider this ``normal'' procedure:
9009 (define (sh-symlink store)
9010 ;; Return a derivation that symlinks the 'bash' executable.
9011 (let* ((drv (package-derivation store bash))
9012 (out (derivation->output-path drv))
9013 (sh (string-append out "/bin/bash")))
9014 (build-expression->derivation store "sh"
9015 `(symlink ,sh %output))))
9018 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
9019 as a monadic function:
9022 (define (sh-symlink)
9023 ;; Same, but return a monadic value.
9024 (mlet %store-monad ((drv (package->derivation bash)))
9025 (gexp->derivation "sh"
9026 #~(symlink (string-append #$drv "/bin/bash")
9030 There are several things to note in the second version: the @code{store}
9031 parameter is now implicit and is ``threaded'' in the calls to the
9032 @code{package->derivation} and @code{gexp->derivation} monadic
9033 procedures, and the monadic value returned by @code{package->derivation}
9034 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
9036 As it turns out, the call to @code{package->derivation} can even be
9037 omitted since it will take place implicitly, as we will see later
9038 (@pxref{G-Expressions}):
9041 (define (sh-symlink)
9042 (gexp->derivation "sh"
9043 #~(symlink (string-append #$bash "/bin/bash")
9048 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
9049 @c for the funny quote.
9050 Calling the monadic @code{sh-symlink} has no effect. As someone once
9051 said, ``you exit a monad like you exit a building on fire: by running''.
9052 So, to exit the monad and get the desired effect, one must use
9053 @code{run-with-store}:
9056 (run-with-store (open-connection) (sh-symlink))
9057 @result{} /gnu/store/...-sh-symlink
9060 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
9061 new ``meta-commands'' to make it easier to deal with monadic procedures:
9062 @code{run-in-store}, and @code{enter-store-monad}. The former is used
9063 to ``run'' a single monadic value through the store:
9066 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
9067 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
9070 The latter enters a recursive REPL, where all the return values are
9071 automatically run through the store:
9074 scheme@@(guile-user)> ,enter-store-monad
9075 store-monad@@(guile-user) [1]> (package->derivation hello)
9076 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
9077 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
9078 $3 = "/gnu/store/@dots{}-foo"
9079 store-monad@@(guile-user) [1]> ,q
9080 scheme@@(guile-user)>
9084 Note that non-monadic values cannot be returned in the
9085 @code{store-monad} REPL.
9087 The main syntactic forms to deal with monads in general are provided by
9088 the @code{(guix monads)} module and are described below.
9090 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
9091 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
9095 @deffn {Scheme Syntax} return @var{val}
9096 Return a monadic value that encapsulates @var{val}.
9099 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
9100 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
9101 procedures @var{mproc}@dots{}@footnote{This operation is commonly
9102 referred to as ``bind'', but that name denotes an unrelated procedure in
9103 Guile. Thus we use this somewhat cryptic symbol inherited from the
9104 Haskell language.}. There can be one @var{mproc} or several of them, as
9109 (with-monad %state-monad
9111 (lambda (x) (return (+ 1 x)))
9112 (lambda (x) (return (* 2 x)))))
9116 @result{} some-state
9120 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
9122 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
9124 Bind the variables @var{var} to the monadic values @var{mval} in
9125 @var{body}, which is a sequence of expressions. As with the bind
9126 operator, this can be thought of as ``unpacking'' the raw, non-monadic
9127 value ``contained'' in @var{mval} and making @var{var} refer to that
9128 raw, non-monadic value within the scope of the @var{body}. The form
9129 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
9130 @var{val}, as per @code{let}. The binding operations occur in sequence
9131 from left to right. The last expression of @var{body} must be a monadic
9132 expression, and its result will become the result of the @code{mlet} or
9133 @code{mlet*} when run in the @var{monad}.
9135 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
9136 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
9139 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
9140 Bind @var{mexp} and the following monadic expressions in sequence,
9141 returning the result of the last expression. Every expression in the
9142 sequence must be a monadic expression.
9144 This is akin to @code{mlet}, except that the return values of the
9145 monadic expressions are ignored. In that sense, it is analogous to
9146 @code{begin}, but applied to monadic expressions.
9149 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
9150 When @var{condition} is true, evaluate the sequence of monadic
9151 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
9152 @var{condition} is false, return @code{*unspecified*} in the current
9153 monad. Every expression in the sequence must be a monadic expression.
9156 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
9157 When @var{condition} is false, evaluate the sequence of monadic
9158 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
9159 @var{condition} is true, return @code{*unspecified*} in the current
9160 monad. Every expression in the sequence must be a monadic expression.
9164 The @code{(guix monads)} module provides the @dfn{state monad}, which
9165 allows an additional value---the state---to be @emph{threaded} through
9166 monadic procedure calls.
9168 @defvr {Scheme Variable} %state-monad
9169 The state monad. Procedures in the state monad can access and change
9170 the state that is threaded.
9172 Consider the example below. The @code{square} procedure returns a value
9173 in the state monad. It returns the square of its argument, but also
9174 increments the current state value:
9178 (mlet %state-monad ((count (current-state)))
9179 (mbegin %state-monad
9180 (set-current-state (+ 1 count))
9183 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
9188 When ``run'' through @code{%state-monad}, we obtain that additional state
9189 value, which is the number of @code{square} calls.
9192 @deffn {Monadic Procedure} current-state
9193 Return the current state as a monadic value.
9196 @deffn {Monadic Procedure} set-current-state @var{value}
9197 Set the current state to @var{value} and return the previous state as a
9201 @deffn {Monadic Procedure} state-push @var{value}
9202 Push @var{value} to the current state, which is assumed to be a list,
9203 and return the previous state as a monadic value.
9206 @deffn {Monadic Procedure} state-pop
9207 Pop a value from the current state and return it as a monadic value.
9208 The state is assumed to be a list.
9211 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
9212 Run monadic value @var{mval} starting with @var{state} as the initial
9213 state. Return two values: the resulting value, and the resulting state.
9216 The main interface to the store monad, provided by the @code{(guix
9217 store)} module, is as follows.
9219 @defvr {Scheme Variable} %store-monad
9220 The store monad---an alias for @code{%state-monad}.
9222 Values in the store monad encapsulate accesses to the store. When its
9223 effect is needed, a value of the store monad must be ``evaluated'' by
9224 passing it to the @code{run-with-store} procedure (see below).
9227 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
9228 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
9229 open store connection.
9232 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
9233 Return as a monadic value the absolute file name in the store of the file
9234 containing @var{text}, a string. @var{references} is a list of store items that the
9235 resulting text file refers to; it defaults to the empty list.
9238 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
9239 Return as a monadic value the absolute file name in the store of the file
9240 containing @var{data}, a bytevector. @var{references} is a list of store
9241 items that the resulting binary file refers to; it defaults to the empty list.
9244 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
9245 [#:recursive? #t] [#:select? (const #t)]
9246 Return the name of @var{file} once interned in the store. Use
9247 @var{name} as its store name, or the basename of @var{file} if
9248 @var{name} is omitted.
9250 When @var{recursive?} is true, the contents of @var{file} are added
9251 recursively; if @var{file} designates a flat file and @var{recursive?}
9252 is true, its contents are added, and its permission bits are kept.
9254 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
9255 @var{stat})} for each directory entry, where @var{file} is the entry's
9256 absolute file name and @var{stat} is the result of @code{lstat}; exclude
9257 entries for which @var{select?} does not return true.
9259 The example below adds a file to the store, under two different names:
9262 (run-with-store (open-connection)
9263 (mlet %store-monad ((a (interned-file "README"))
9264 (b (interned-file "README" "LEGU-MIN")))
9265 (return (list a b))))
9267 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
9272 The @code{(guix packages)} module exports the following package-related
9275 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
9276 [#:system (%current-system)] [#:target #f] @
9279 value in the absolute file name of @var{file} within the @var{output}
9280 directory of @var{package}. When @var{file} is omitted, return the name
9281 of the @var{output} directory of @var{package}. When @var{target} is
9282 true, use it as a cross-compilation target triplet.
9284 Note that this procedure does @emph{not} build @var{package}. Thus, the
9285 result might or might not designate an existing file. We recommend not
9286 using this procedure unless you know what you are doing.
9289 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
9290 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
9291 @var{target} [@var{system}]
9292 Monadic version of @code{package-derivation} and
9293 @code{package-cross-derivation} (@pxref{Defining Packages}).
9298 @section G-Expressions
9300 @cindex G-expression
9301 @cindex build code quoting
9302 So we have ``derivations'', which represent a sequence of build actions
9303 to be performed to produce an item in the store (@pxref{Derivations}).
9304 These build actions are performed when asking the daemon to actually
9305 build the derivations; they are run by the daemon in a container
9306 (@pxref{Invoking guix-daemon}).
9308 @cindex code staging
9309 @cindex staging, of code
9310 @cindex strata of code
9311 It should come as no surprise that we like to write these build actions
9312 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
9313 code@footnote{The term @dfn{stratum} in this context was coined by
9314 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
9315 Kiselyov, who has written insightful
9316 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
9317 on this topic}, refers to this kind of code generation as
9318 @dfn{staging}.}: the ``host code''---code that defines packages, talks
9319 to the daemon, etc.---and the ``build code''---code that actually
9320 performs build actions, such as making directories, invoking
9321 @command{make}, and so on (@pxref{Build Phases}).
9323 To describe a derivation and its build actions, one typically needs to
9324 embed build code inside host code. It boils down to manipulating build
9325 code as data, and the homoiconicity of Scheme---code has a direct
9326 representation as data---comes in handy for that. But we need more than
9327 the normal @code{quasiquote} mechanism in Scheme to construct build
9330 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
9331 S-expressions adapted to build expressions. G-expressions, or
9332 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
9333 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
9334 @code{#$}, and @code{#$@@}), which are comparable to
9335 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
9336 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
9337 GNU Guile Reference Manual}). However, there are major differences:
9341 Gexps are meant to be written to a file and run or manipulated by other
9345 When a high-level object such as a package or derivation is unquoted
9346 inside a gexp, the result is as if its output file name had been
9350 Gexps carry information about the packages or derivations they refer to,
9351 and these dependencies are automatically added as inputs to the build
9352 processes that use them.
9355 @cindex lowering, of high-level objects in gexps
9356 This mechanism is not limited to package and derivation
9357 objects: @dfn{compilers} able to ``lower'' other high-level objects to
9358 derivations or files in the store can be defined,
9359 such that these objects can also be inserted
9360 into gexps. For example, a useful type of high-level objects that can be
9361 inserted in a gexp is ``file-like objects'', which make it easy to
9362 add files to the store and to refer to them in
9363 derivations and such (see @code{local-file} and @code{plain-file}
9366 To illustrate the idea, here is an example of a gexp:
9373 (symlink (string-append #$coreutils "/bin/ls")
9377 This gexp can be passed to @code{gexp->derivation}; we obtain a
9378 derivation that builds a directory containing exactly one symlink to
9379 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
9382 (gexp->derivation "the-thing" build-exp)
9385 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
9386 substituted to the reference to the @var{coreutils} package in the
9387 actual build code, and @var{coreutils} is automatically made an input to
9388 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
9389 output)}) is replaced by a string containing the directory name of the
9390 output of the derivation.
9392 @cindex cross compilation
9393 In a cross-compilation context, it is useful to distinguish between
9394 references to the @emph{native} build of a package---that can run on the
9395 host---versus references to cross builds of a package. To that end, the
9396 @code{#+} plays the same role as @code{#$}, but is a reference to a
9397 native package build:
9400 (gexp->derivation "vi"
9403 (mkdir (string-append #$output "/bin"))
9404 (system* (string-append #+coreutils "/bin/ln")
9406 (string-append #$emacs "/bin/emacs")
9407 (string-append #$output "/bin/vi")))
9408 #:target "aarch64-linux-gnu")
9412 In the example above, the native build of @var{coreutils} is used, so
9413 that @command{ln} can actually run on the host; but then the
9414 cross-compiled build of @var{emacs} is referenced.
9416 @cindex imported modules, for gexps
9417 @findex with-imported-modules
9418 Another gexp feature is @dfn{imported modules}: sometimes you want to be
9419 able to use certain Guile modules from the ``host environment'' in the
9420 gexp, so those modules should be imported in the ``build environment''.
9421 The @code{with-imported-modules} form allows you to express that:
9424 (let ((build (with-imported-modules '((guix build utils))
9426 (use-modules (guix build utils))
9427 (mkdir-p (string-append #$output "/bin"))))))
9428 (gexp->derivation "empty-dir"
9431 (display "success!\n")
9436 In this example, the @code{(guix build utils)} module is automatically
9437 pulled into the isolated build environment of our gexp, such that
9438 @code{(use-modules (guix build utils))} works as expected.
9440 @cindex module closure
9441 @findex source-module-closure
9442 Usually you want the @emph{closure} of the module to be imported---i.e.,
9443 the module itself and all the modules it depends on---rather than just
9444 the module; failing to do that, attempts to use the module will fail
9445 because of missing dependent modules. The @code{source-module-closure}
9446 procedure computes the closure of a module by looking at its source file
9447 headers, which comes in handy in this case:
9450 (use-modules (guix modules)) ;for 'source-module-closure'
9452 (with-imported-modules (source-module-closure
9453 '((guix build utils)
9455 (gexp->derivation "something-with-vms"
9457 (use-modules (guix build utils)
9462 @cindex extensions, for gexps
9463 @findex with-extensions
9464 In the same vein, sometimes you want to import not just pure-Scheme
9465 modules, but also ``extensions'' such as Guile bindings to C libraries
9466 or other ``full-blown'' packages. Say you need the @code{guile-json}
9467 package available on the build side, here's how you would do it:
9470 (use-modules (gnu packages guile)) ;for 'guile-json'
9472 (with-extensions (list guile-json)
9473 (gexp->derivation "something-with-json"
9475 (use-modules (json))
9479 The syntactic form to construct gexps is summarized below.
9481 @deffn {Scheme Syntax} #~@var{exp}
9482 @deffnx {Scheme Syntax} (gexp @var{exp})
9483 Return a G-expression containing @var{exp}. @var{exp} may contain one
9484 or more of the following forms:
9488 @itemx (ungexp @var{obj})
9489 Introduce a reference to @var{obj}. @var{obj} may have one of the
9490 supported types, for example a package or a
9491 derivation, in which case the @code{ungexp} form is replaced by its
9492 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
9494 If @var{obj} is a list, it is traversed and references to supported
9495 objects are substituted similarly.
9497 If @var{obj} is another gexp, its contents are inserted and its
9498 dependencies are added to those of the containing gexp.
9500 If @var{obj} is another kind of object, it is inserted as is.
9502 @item #$@var{obj}:@var{output}
9503 @itemx (ungexp @var{obj} @var{output})
9504 This is like the form above, but referring explicitly to the
9505 @var{output} of @var{obj}---this is useful when @var{obj} produces
9506 multiple outputs (@pxref{Packages with Multiple Outputs}).
9509 @itemx #+@var{obj}:output
9510 @itemx (ungexp-native @var{obj})
9511 @itemx (ungexp-native @var{obj} @var{output})
9512 Same as @code{ungexp}, but produces a reference to the @emph{native}
9513 build of @var{obj} when used in a cross compilation context.
9515 @item #$output[:@var{output}]
9516 @itemx (ungexp output [@var{output}])
9517 Insert a reference to derivation output @var{output}, or to the main
9518 output when @var{output} is omitted.
9520 This only makes sense for gexps passed to @code{gexp->derivation}.
9523 @itemx (ungexp-splicing @var{lst})
9524 Like the above, but splices the contents of @var{lst} inside the
9528 @itemx (ungexp-native-splicing @var{lst})
9529 Like the above, but refers to native builds of the objects listed in
9534 G-expressions created by @code{gexp} or @code{#~} are run-time objects
9535 of the @code{gexp?} type (see below).
9538 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
9539 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
9540 in their execution environment.
9542 Each item in @var{modules} can be the name of a module, such as
9543 @code{(guix build utils)}, or it can be a module name, followed by an
9544 arrow, followed by a file-like object:
9547 `((guix build utils)
9549 ((guix config) => ,(scheme-file "config.scm"
9550 #~(define-module @dots{}))))
9554 In the example above, the first two modules are taken from the search
9555 path, and the last one is created from the given file-like object.
9557 This form has @emph{lexical} scope: it has an effect on the gexps
9558 directly defined in @var{body}@dots{}, but not on those defined, say, in
9559 procedures called from @var{body}@dots{}.
9562 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
9563 Mark the gexps defined in @var{body}@dots{} as requiring
9564 @var{extensions} in their build and execution environment.
9565 @var{extensions} is typically a list of package objects such as those
9566 defined in the @code{(gnu packages guile)} module.
9568 Concretely, the packages listed in @var{extensions} are added to the
9569 load path while compiling imported modules in @var{body}@dots{}; they
9570 are also added to the load path of the gexp returned by
9574 @deffn {Scheme Procedure} gexp? @var{obj}
9575 Return @code{#t} if @var{obj} is a G-expression.
9578 G-expressions are meant to be written to disk, either as code building
9579 some derivation, or as plain files in the store. The monadic procedures
9580 below allow you to do that (@pxref{The Store Monad}, for more
9581 information about monads).
9583 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
9584 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
9585 [#:hash #f] [#:hash-algo #f] @
9586 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
9587 [#:module-path @code{%load-path}] @
9588 [#:effective-version "2.2"] @
9589 [#:references-graphs #f] [#:allowed-references #f] @
9590 [#:disallowed-references #f] @
9591 [#:leaked-env-vars #f] @
9592 [#:script-name (string-append @var{name} "-builder")] @
9593 [#:deprecation-warnings #f] @
9594 [#:local-build? #f] [#:substitutable? #t] @
9595 [#:properties '()] [#:guile-for-build #f]
9596 Return a derivation @var{name} that runs @var{exp} (a gexp) with
9597 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
9598 stored in a file called @var{script-name}. When @var{target} is true,
9599 it is used as the cross-compilation target triplet for packages referred
9602 @var{modules} is deprecated in favor of @code{with-imported-modules}.
9604 make @var{modules} available in the evaluation context of @var{exp};
9605 @var{modules} is a list of names of Guile modules searched in
9606 @var{module-path} to be copied in the store, compiled, and made available in
9607 the load path during the execution of @var{exp}---e.g., @code{((guix
9608 build utils) (guix build gnu-build-system))}.
9610 @var{effective-version} determines the string to use when adding extensions of
9611 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
9613 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
9616 When @var{references-graphs} is true, it must be a list of tuples of one of the
9620 (@var{file-name} @var{package})
9621 (@var{file-name} @var{package} @var{output})
9622 (@var{file-name} @var{derivation})
9623 (@var{file-name} @var{derivation} @var{output})
9624 (@var{file-name} @var{store-item})
9627 The right-hand-side of each element of @var{references-graphs} is automatically made
9628 an input of the build process of @var{exp}. In the build environment, each
9629 @var{file-name} contains the reference graph of the corresponding item, in a simple
9632 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
9633 In the latter case, the list denotes store items that the result is allowed to
9634 refer to. Any reference to another store item will lead to a build error.
9635 Similarly for @var{disallowed-references}, which can list items that must not be
9636 referenced by the outputs.
9638 @var{deprecation-warnings} determines whether to show deprecation warnings while
9639 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
9641 The other arguments are as for @code{derivation} (@pxref{Derivations}).
9644 @cindex file-like objects
9645 The @code{local-file}, @code{plain-file}, @code{computed-file},
9646 @code{program-file}, and @code{scheme-file} procedures below return
9647 @dfn{file-like objects}. That is, when unquoted in a G-expression,
9648 these objects lead to a file in the store. Consider this G-expression:
9651 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
9652 #$(local-file "/tmp/my-nscd.conf"))
9655 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
9656 to the store. Once expanded, for instance @i{via}
9657 @code{gexp->derivation}, the G-expression refers to that copy under
9658 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
9659 does not have any effect on what the G-expression does.
9660 @code{plain-file} can be used similarly; it differs in that the file
9661 content is directly passed as a string.
9663 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
9664 [#:recursive? #f] [#:select? (const #t)]
9665 Return an object representing local file @var{file} to add to the store;
9666 this object can be used in a gexp. If @var{file} is a literal string
9667 denoting a relative file name, it is looked up relative to the source
9668 file where it appears; if @var{file} is not a literal string, it is
9669 looked up relative to the current working directory at run time.
9670 @var{file} will be added to the store under @var{name}--by default the
9671 base name of @var{file}.
9673 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
9674 designates a flat file and @var{recursive?} is true, its contents are added, and its
9675 permission bits are kept.
9677 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
9678 @var{stat})} for each directory entry, where @var{file} is the entry's
9679 absolute file name and @var{stat} is the result of @code{lstat}; exclude
9680 entries for which @var{select?} does not return true.
9682 This is the declarative counterpart of the @code{interned-file} monadic
9683 procedure (@pxref{The Store Monad, @code{interned-file}}).
9686 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
9687 Return an object representing a text file called @var{name} with the given
9688 @var{content} (a string or a bytevector) to be added to the store.
9690 This is the declarative counterpart of @code{text-file}.
9693 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
9696 Return an object representing the store item @var{name}, a file or
9697 directory computed by @var{gexp}. When @var{local-build?} is true (the
9698 default), the derivation is built locally. @var{options} is a list of
9699 additional arguments to pass to @code{gexp->derivation}.
9701 This is the declarative counterpart of @code{gexp->derivation}.
9704 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
9705 [#:guile (default-guile)] [#:module-path %load-path] @
9706 [#:system (%current-system)] [#:target #f]
9707 Return an executable script @var{name} that runs @var{exp} using
9708 @var{guile}, with @var{exp}'s imported modules in its search path.
9709 Look up @var{exp}'s modules in @var{module-path}.
9711 The example below builds a script that simply invokes the @command{ls}
9715 (use-modules (guix gexp) (gnu packages base))
9717 (gexp->script "list-files"
9718 #~(execl #$(file-append coreutils "/bin/ls")
9722 When ``running'' it through the store (@pxref{The Store Monad,
9723 @code{run-with-store}}), we obtain a derivation that produces an
9724 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
9727 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
9729 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
9733 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
9734 [#:guile #f] [#:module-path %load-path]
9735 Return an object representing the executable store item @var{name} that
9736 runs @var{gexp}. @var{guile} is the Guile package used to execute that
9737 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
9739 This is the declarative counterpart of @code{gexp->script}.
9742 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
9743 [#:set-load-path? #t] [#:module-path %load-path] @
9745 [#:guile (default-guile)]
9746 Return a derivation that builds a file @var{name} containing @var{exp}.
9747 When @var{splice?} is true, @var{exp} is considered to be a list of
9748 expressions that will be spliced in the resulting file.
9750 When @var{set-load-path?} is true, emit code in the resulting file to
9751 set @code{%load-path} and @code{%load-compiled-path} to honor
9752 @var{exp}'s imported modules. Look up @var{exp}'s modules in
9755 The resulting file holds references to all the dependencies of @var{exp}
9756 or a subset thereof.
9759 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
9760 [#:splice? #f] [#:set-load-path? #t]
9761 Return an object representing the Scheme file @var{name} that contains
9764 This is the declarative counterpart of @code{gexp->file}.
9767 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
9768 Return as a monadic value a derivation that builds a text file
9769 containing all of @var{text}. @var{text} may list, in addition to
9770 strings, objects of any type that can be used in a gexp: packages,
9771 derivations, local file objects, etc. The resulting store file holds
9772 references to all these.
9774 This variant should be preferred over @code{text-file} anytime the file
9775 to create will reference items from the store. This is typically the
9776 case when building a configuration file that embeds store file names,
9780 (define (profile.sh)
9781 ;; Return the name of a shell script in the store that
9782 ;; initializes the 'PATH' environment variable.
9783 (text-file* "profile.sh"
9784 "export PATH=" coreutils "/bin:"
9785 grep "/bin:" sed "/bin\n"))
9788 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
9789 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
9790 preventing them from being garbage-collected during its lifetime.
9793 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
9794 Return an object representing store file @var{name} containing
9795 @var{text}. @var{text} is a sequence of strings and file-like objects,
9799 (mixed-text-file "profile"
9800 "export PATH=" coreutils "/bin:" grep "/bin")
9803 This is the declarative counterpart of @code{text-file*}.
9806 @deffn {Scheme Procedure} file-union @var{name} @var{files}
9807 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
9808 Each item in @var{files} must be a two-element list where the first element is the
9809 file name to use in the new directory, and the second element is a gexp
9810 denoting the target file. Here's an example:
9814 `(("hosts" ,(plain-file "hosts"
9815 "127.0.0.1 localhost"))
9816 ("bashrc" ,(plain-file "bashrc"
9817 "alias ls='ls --color=auto'"))))
9820 This yields an @code{etc} directory containing these two files.
9823 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
9824 Return a directory that is the union of @var{things}, where @var{things} is a list of
9825 file-like objects denoting directories. For example:
9828 (directory-union "guile+emacs" (list guile emacs))
9831 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
9834 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
9835 Return a file-like object that expands to the concatenation of @var{obj}
9836 and @var{suffix}, where @var{obj} is a lowerable object and each
9837 @var{suffix} is a string.
9839 As an example, consider this gexp:
9842 (gexp->script "run-uname"
9843 #~(system* #$(file-append coreutils
9847 The same effect could be achieved with:
9850 (gexp->script "run-uname"
9851 #~(system* (string-append #$coreutils
9855 There is one difference though: in the @code{file-append} case, the
9856 resulting script contains the absolute file name as a string, whereas in
9857 the second case, the resulting script contains a @code{(string-append
9858 @dots{})} expression to construct the file name @emph{at run time}.
9861 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
9862 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
9863 Bind @var{system} to the currently targeted system---e.g.,
9864 @code{"x86_64-linux"}---within @var{body}.
9866 In the second case, additionally bind @var{target} to the current
9867 cross-compilation target---a GNU triplet such as
9868 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
9871 @code{let-system} is useful in the occasional case where the object
9872 spliced into the gexp depends on the target system, as in this example:
9876 #+(let-system system
9877 (cond ((string-prefix? "armhf-" system)
9878 (file-append qemu "/bin/qemu-system-arm"))
9879 ((string-prefix? "x86_64-" system)
9880 (file-append qemu "/bin/qemu-system-x86_64"))
9883 "-net" "user" #$image)
9887 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
9888 This macro is similar to the @code{parameterize} form for
9889 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
9890 Guile Reference Manual}). The key difference is that it takes effect
9891 when the file-like object returned by @var{exp} is lowered to a
9892 derivation or store item.
9894 A typical use of @code{with-parameters} is to force the system in effect
9898 (with-parameters ((%current-system "i686-linux"))
9902 The example above returns an object that corresponds to the i686 build
9903 of Coreutils, regardless of the current value of @code{%current-system}.
9907 Of course, in addition to gexps embedded in ``host'' code, there are
9908 also modules containing build tools. To make it clear that they are
9909 meant to be used in the build stratum, these modules are kept in the
9910 @code{(guix build @dots{})} name space.
9912 @cindex lowering, of high-level objects in gexps
9913 Internally, high-level objects are @dfn{lowered}, using their compiler,
9914 to either derivations or store items. For instance, lowering a package
9915 yields a derivation, and lowering a @code{plain-file} yields a store
9916 item. This is achieved using the @code{lower-object} monadic procedure.
9918 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
9920 Return as a value in @code{%store-monad} the derivation or store item
9921 corresponding to @var{obj} for @var{system}, cross-compiling for
9922 @var{target} if @var{target} is true. @var{obj} must be an object that
9923 has an associated gexp compiler, such as a @code{<package>}.
9926 @node Invoking guix repl
9927 @section Invoking @command{guix repl}
9929 @cindex REPL, read-eval-print loop, script
9930 The @command{guix repl} command makes it easier to program Guix in Guile
9931 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
9932 programming (@pxref{Using Guile Interactively,,, guile,
9933 GNU Guile Reference Manual}), or by running Guile scripts
9934 (@pxref{Running Guile Scripts,,, guile,
9935 GNU Guile Reference Manual}).
9936 Compared to just launching the @command{guile}
9937 command, @command{guix repl} guarantees that all the Guix modules and all its
9938 dependencies are available in the search path.
9940 The general syntax is:
9943 guix repl @var{options} [@var{file} @var{args}]
9946 When a @var{file} argument is provided, @var{file} is
9947 executed as a Guile scripts:
9950 guix repl my-script.scm
9953 To pass arguments to the script, use @code{--} to prevent them from
9954 being interpreted as arguments to @command{guix repl} itself:
9957 guix repl -- my-script.scm --input=foo.txt
9960 To make a script executable directly from the shell, using the guix
9961 executable that is on the user's search path, add the following two
9962 lines at the top of the script:
9965 @code{#!/usr/bin/env -S guix repl --}
9969 Without a file name argument, a Guile REPL is started:
9973 scheme@@(guile-user)> ,use (gnu packages base)
9974 scheme@@(guile-user)> coreutils
9975 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
9979 In addition, @command{guix repl} implements a simple machine-readable REPL
9980 protocol for use by @code{(guix inferior)}, a facility to interact with
9981 @dfn{inferiors}, separate processes running a potentially different revision
9984 The available options are as follows:
9987 @item --type=@var{type}
9988 @itemx -t @var{type}
9989 Start a REPL of the given @var{TYPE}, which can be one of the following:
9993 This is default, and it spawns a standard full-featured Guile REPL.
9995 Spawn a REPL that uses the machine-readable protocol. This is the protocol
9996 that the @code{(guix inferior)} module speaks.
9999 @item --listen=@var{endpoint}
10000 By default, @command{guix repl} reads from standard input and writes to
10001 standard output. When this option is passed, it will instead listen for
10002 connections on @var{endpoint}. Here are examples of valid options:
10005 @item --listen=tcp:37146
10006 Accept connections on localhost on port 37146.
10008 @item --listen=unix:/tmp/socket
10009 Accept connections on the Unix-domain socket @file{/tmp/socket}.
10012 @item --load-path=@var{directory}
10013 @itemx -L @var{directory}
10014 Add @var{directory} to the front of the package module search path
10015 (@pxref{Package Modules}).
10017 This allows users to define their own packages and make them visible to
10018 the script or REPL.
10021 Inhibit loading of the @file{~/.guile} file. By default, that
10022 configuration file is loaded when spawning a @code{guile} REPL.
10025 @c *********************************************************************
10029 This section describes Guix command-line utilities. Some of them are
10030 primarily targeted at developers and users who write new package
10031 definitions, while others are more generally useful. They complement
10032 the Scheme programming interface of Guix in a convenient way.
10035 * Invoking guix build:: Building packages from the command line.
10036 * Invoking guix edit:: Editing package definitions.
10037 * Invoking guix download:: Downloading a file and printing its hash.
10038 * Invoking guix hash:: Computing the cryptographic hash of a file.
10039 * Invoking guix import:: Importing package definitions.
10040 * Invoking guix refresh:: Updating package definitions.
10041 * Invoking guix lint:: Finding errors in package definitions.
10042 * Invoking guix size:: Profiling disk usage.
10043 * Invoking guix graph:: Visualizing the graph of packages.
10044 * Invoking guix publish:: Sharing substitutes.
10045 * Invoking guix challenge:: Challenging substitute servers.
10046 * Invoking guix copy:: Copying to and from a remote store.
10047 * Invoking guix container:: Process isolation.
10048 * Invoking guix weather:: Assessing substitute availability.
10049 * Invoking guix processes:: Listing client processes.
10052 @node Invoking guix build
10053 @section Invoking @command{guix build}
10055 @cindex package building
10056 @cindex @command{guix build}
10057 The @command{guix build} command builds packages or derivations and
10058 their dependencies, and prints the resulting store paths. Note that it
10059 does not modify the user's profile---this is the job of the
10060 @command{guix package} command (@pxref{Invoking guix package}). Thus,
10061 it is mainly useful for distribution developers.
10063 The general syntax is:
10066 guix build @var{options} @var{package-or-derivation}@dots{}
10069 As an example, the following command builds the latest versions of Emacs
10070 and of Guile, displays their build logs, and finally displays the
10071 resulting directories:
10074 guix build emacs guile
10077 Similarly, the following command builds all the available packages:
10080 guix build --quiet --keep-going \
10081 `guix package -A | cut -f1,2 --output-delimiter=@@`
10084 @var{package-or-derivation} may be either the name of a package found in
10085 the software distribution such as @code{coreutils} or
10086 @code{coreutils@@8.20}, or a derivation such as
10087 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
10088 package with the corresponding name (and optionally version) is searched
10089 for among the GNU distribution modules (@pxref{Package Modules}).
10091 Alternatively, the @option{--expression} option may be used to specify a
10092 Scheme expression that evaluates to a package; this is useful when
10093 disambiguating among several same-named packages or package variants is
10096 There may be zero or more @var{options}. The available options are
10097 described in the subsections below.
10100 * Common Build Options:: Build options for most commands.
10101 * Package Transformation Options:: Creating variants of packages.
10102 * Additional Build Options:: Options specific to 'guix build'.
10103 * Debugging Build Failures:: Real life packaging experience.
10106 @node Common Build Options
10107 @subsection Common Build Options
10109 A number of options that control the build process are common to
10110 @command{guix build} and other commands that can spawn builds, such as
10111 @command{guix package} or @command{guix archive}. These are the
10116 @item --load-path=@var{directory}
10117 @itemx -L @var{directory}
10118 Add @var{directory} to the front of the package module search path
10119 (@pxref{Package Modules}).
10121 This allows users to define their own packages and make them visible to
10122 the command-line tools.
10124 @item --keep-failed
10126 Keep the build tree of failed builds. Thus, if a build fails, its build
10127 tree is kept under @file{/tmp}, in a directory whose name is shown at
10128 the end of the build log. This is useful when debugging build issues.
10129 @xref{Debugging Build Failures}, for tips and tricks on how to debug
10132 This option implies @option{--no-offload}, and it has no effect when
10133 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
10134 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
10138 Keep going when some of the derivations fail to build; return only once
10139 all the builds have either completed or failed.
10141 The default behavior is to stop as soon as one of the specified
10142 derivations has failed.
10146 Do not build the derivations.
10148 @anchor{fallback-option}
10150 When substituting a pre-built binary fails, fall back to building
10151 packages locally (@pxref{Substitution Failure}).
10153 @item --substitute-urls=@var{urls}
10154 @anchor{client-substitute-urls}
10155 Consider @var{urls} the whitespace-separated list of substitute source
10156 URLs, overriding the default list of URLs of @command{guix-daemon}
10157 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
10159 This means that substitutes may be downloaded from @var{urls}, provided
10160 they are signed by a key authorized by the system administrator
10161 (@pxref{Substitutes}).
10163 When @var{urls} is the empty string, substitutes are effectively
10166 @item --no-substitutes
10167 Do not use substitutes for build products. That is, always build things
10168 locally instead of allowing downloads of pre-built binaries
10169 (@pxref{Substitutes}).
10172 Do not ``graft'' packages. In practice, this means that package updates
10173 available as grafts are not applied. @xref{Security Updates}, for more
10174 information on grafts.
10176 @item --rounds=@var{n}
10177 Build each derivation @var{n} times in a row, and raise an error if
10178 consecutive build results are not bit-for-bit identical.
10180 This is a useful way to detect non-deterministic builds processes.
10181 Non-deterministic build processes are a problem because they make it
10182 practically impossible for users to @emph{verify} whether third-party
10183 binaries are genuine. @xref{Invoking guix challenge}, for more.
10185 When used in conjunction with @option{--keep-failed}, the differing
10186 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
10187 This makes it easy to look for differences between the two results.
10190 Do not use offload builds to other machines (@pxref{Daemon Offload
10191 Setup}). That is, always build things locally instead of offloading
10192 builds to remote machines.
10194 @item --max-silent-time=@var{seconds}
10195 When the build or substitution process remains silent for more than
10196 @var{seconds}, terminate it and report a build failure.
10198 By default, the daemon's setting is honored (@pxref{Invoking
10199 guix-daemon, @option{--max-silent-time}}).
10201 @item --timeout=@var{seconds}
10202 Likewise, when the build or substitution process lasts for more than
10203 @var{seconds}, terminate it and report a build failure.
10205 By default, the daemon's setting is honored (@pxref{Invoking
10206 guix-daemon, @option{--timeout}}).
10208 @c Note: This option is actually not part of %standard-build-options but
10209 @c most programs honor it.
10210 @cindex verbosity, of the command-line tools
10211 @cindex build logs, verbosity
10212 @item -v @var{level}
10213 @itemx --verbosity=@var{level}
10214 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
10215 output is produced, 1 is for quiet output, and 2 shows all the build log
10216 output on standard error.
10218 @item --cores=@var{n}
10220 Allow the use of up to @var{n} CPU cores for the build. The special
10221 value @code{0} means to use as many CPU cores as available.
10223 @item --max-jobs=@var{n}
10225 Allow at most @var{n} build jobs in parallel. @xref{Invoking
10226 guix-daemon, @option{--max-jobs}}, for details about this option and the
10227 equivalent @command{guix-daemon} option.
10229 @item --debug=@var{level}
10230 Produce debugging output coming from the build daemon. @var{level} must be an
10231 integer between 0 and 5; higher means more verbose output. Setting a level of
10232 4 or more may be helpful when debugging setup issues with the build daemon.
10236 Behind the scenes, @command{guix build} is essentially an interface to
10237 the @code{package-derivation} procedure of the @code{(guix packages)}
10238 module, and to the @code{build-derivations} procedure of the @code{(guix
10239 derivations)} module.
10241 In addition to options explicitly passed on the command line,
10242 @command{guix build} and other @command{guix} commands that support
10243 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
10245 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
10246 Users can define this variable to a list of command line options that
10247 will automatically be used by @command{guix build} and other
10248 @command{guix} commands that can perform builds, as in the example
10252 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
10255 These options are parsed independently, and the result is appended to
10256 the parsed command-line options.
10260 @node Package Transformation Options
10261 @subsection Package Transformation Options
10263 @cindex package variants
10264 Another set of command-line options supported by @command{guix build}
10265 and also @command{guix package} are @dfn{package transformation
10266 options}. These are options that make it possible to define @dfn{package
10267 variants}---for instance, packages built from different source code.
10268 This is a convenient way to create customized packages on the fly
10269 without having to type in the definitions of package variants
10270 (@pxref{Defining Packages}).
10272 Package transformation options are preserved across upgrades:
10273 @command{guix upgrade} attempts to apply transformation options
10274 initially used when creating the profile to the upgraded packages.
10276 The available options are listed below. Most commands support them and
10277 also support a @option{--help-transform} option that lists all the
10278 available options and a synopsis (these options are not shown in the
10279 @option{--help} output for brevity).
10283 @item --with-source=@var{source}
10284 @itemx --with-source=@var{package}=@var{source}
10285 @itemx --with-source=@var{package}@@@var{version}=@var{source}
10286 Use @var{source} as the source of @var{package}, and @var{version} as
10287 its version number.
10288 @var{source} must be a file name or a URL, as for @command{guix
10289 download} (@pxref{Invoking guix download}).
10291 When @var{package} is omitted,
10292 it is taken to be the package name specified on the
10293 command line that matches the base of @var{source}---e.g.,
10294 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
10295 package is @code{guile}.
10297 Likewise, when @var{version} is omitted, the version string is inferred from
10298 @var{source}; in the previous example, it is @code{2.0.10}.
10300 This option allows users to try out versions of packages other than the
10301 one provided by the distribution. The example below downloads
10302 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
10303 the @code{ed} package:
10306 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
10309 As a developer, @option{--with-source} makes it easy to test release
10313 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
10316 @dots{} or to build from a checkout in a pristine environment:
10319 $ git clone git://git.sv.gnu.org/guix.git
10320 $ guix build guix --with-source=guix@@1.0=./guix
10323 @item --with-input=@var{package}=@var{replacement}
10324 Replace dependency on @var{package} by a dependency on
10325 @var{replacement}. @var{package} must be a package name, and
10326 @var{replacement} must be a package specification such as @code{guile}
10327 or @code{guile@@1.8}.
10329 For instance, the following command builds Guix, but replaces its
10330 dependency on the current stable version of Guile with a dependency on
10331 the legacy version of Guile, @code{guile@@2.0}:
10334 guix build --with-input=guile=guile@@2.0 guix
10337 This is a recursive, deep replacement. So in this example, both
10338 @code{guix} and its dependency @code{guile-json} (which also depends on
10339 @code{guile}) get rebuilt against @code{guile@@2.0}.
10341 This is implemented using the @code{package-input-rewriting} Scheme
10342 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
10344 @item --with-graft=@var{package}=@var{replacement}
10345 This is similar to @option{--with-input} but with an important difference:
10346 instead of rebuilding the whole dependency chain, @var{replacement} is
10347 built and then @dfn{grafted} onto the binaries that were initially
10348 referring to @var{package}. @xref{Security Updates}, for more
10349 information on grafts.
10351 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
10352 and all its dependencies, replacing references to the version of GnuTLS
10353 they currently refer to:
10356 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
10359 This has the advantage of being much faster than rebuilding everything.
10360 But there is a caveat: it works if and only if @var{package} and
10361 @var{replacement} are strictly compatible---for example, if they provide
10362 a library, the application binary interface (ABI) of those libraries
10363 must be compatible. If @var{replacement} is somehow incompatible with
10364 @var{package}, then the resulting package may be unusable. Use with
10367 @cindex debugging info, rebuilding
10368 @item --with-debug-info=@var{package}
10369 Build @var{package} in a way that preserves its debugging info and graft
10370 it onto packages that depend on it. This is useful if @var{package}
10371 does not already provide debugging info as a @code{debug} output
10372 (@pxref{Installing Debugging Files}).
10374 For example, suppose you're experiencing a crash in Inkscape and would
10375 like to see what's up in GLib, a library deep down in Inkscape's
10376 dependency graph. GLib lacks a @code{debug} output, so debugging is
10377 tough. Fortunately, you rebuild GLib with debugging info and tack it on
10381 guix install inkscape --with-debug-info=glib
10384 Only GLib needs to be recompiled so this takes a reasonable amount of
10385 time. @xref{Installing Debugging Files}, for more info.
10388 Under the hood, this option works by passing the @samp{#:strip-binaries?
10389 #f} to the build system of the package of interest (@pxref{Build
10390 Systems}). Most build systems support that option but some do not. In
10391 that case, an error is raised.
10393 Likewise, if a C/C++ package is built without @code{-g} (which is rarely
10394 the case), debugging info will remain unavailable even when
10395 @code{#:strip-binaries?} is false.
10398 @cindex tool chain, changing the build tool chain of a package
10399 @item --with-c-toolchain=@var{package}=@var{toolchain}
10400 This option changes the compilation of @var{package} and everything that
10401 depends on it so that they get built with @var{toolchain} instead of the
10402 default GNU tool chain for C/C++.
10404 Consider this example:
10407 guix build octave-cli \
10408 --with-c-toolchain=fftw=gcc-toolchain@@10 \
10409 --with-c-toolchain=fftwf=gcc-toolchain@@10
10412 The command above builds a variant of the @code{fftw} and @code{fftwf}
10413 packages using version 10 of @code{gcc-toolchain} instead of the default
10414 tool chain, and then builds a variant of the GNU@tie{}Octave
10415 command-line interface using them. GNU@tie{}Octave itself is also built
10416 with @code{gcc-toolchain@@10}.
10418 This other example builds the Hardware Locality (@code{hwloc}) library
10419 and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
10423 guix build --with-c-toolchain=hwloc=clang-toolchain \
10424 intel-mpi-benchmarks
10428 There can be application binary interface (ABI) incompatibilities among
10429 tool chains. This is particularly true of the C++ standard library and
10430 run-time support libraries such as that of OpenMP@. By rebuilding all
10431 dependents with the same tool chain, @option{--with-c-toolchain} minimizes
10432 the risks of incompatibility but cannot entirely eliminate them. Choose
10433 @var{package} wisely.
10436 @item --with-git-url=@var{package}=@var{url}
10437 @cindex Git, using the latest commit
10438 @cindex latest commit, building
10439 Build @var{package} from the latest commit of the @code{master} branch of the
10440 Git repository at @var{url}. Git sub-modules of the repository are fetched,
10443 For example, the following command builds the NumPy Python library against the
10444 latest commit of the master branch of Python itself:
10447 guix build python-numpy \
10448 --with-git-url=python=https://github.com/python/cpython
10451 This option can also be combined with @option{--with-branch} or
10452 @option{--with-commit} (see below).
10454 @cindex continuous integration
10455 Obviously, since it uses the latest commit of the given branch, the result of
10456 such a command varies over time. Nevertheless it is a convenient way to
10457 rebuild entire software stacks against the latest commit of one or more
10458 packages. This is particularly useful in the context of continuous
10461 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
10462 consecutive accesses to the same repository. You may want to clean it up once
10463 in a while to save disk space.
10465 @item --with-branch=@var{package}=@var{branch}
10466 Build @var{package} from the latest commit of @var{branch}. If the
10467 @code{source} field of @var{package} is an origin with the @code{git-fetch}
10468 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
10469 repository URL is taken from that @code{source}. Otherwise you have to use
10470 @option{--with-git-url} to specify the URL of the Git repository.
10472 For instance, the following command builds @code{guile-sqlite3} from the
10473 latest commit of its @code{master} branch, and then builds @code{guix} (which
10474 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
10475 specific @code{guile-sqlite3} build:
10478 guix build --with-branch=guile-sqlite3=master cuirass
10481 @item --with-commit=@var{package}=@var{commit}
10482 This is similar to @option{--with-branch}, except that it builds from
10483 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
10484 Git commit SHA1 identifier or a tag.
10486 @item --with-patch=@var{package}=@var{file}
10487 Add @var{file} to the list of patches applied to @var{package}, where
10488 @var{package} is a spec such as @code{python@@3.8} or @code{glibc}.
10489 @var{file} must contain a patch; it is applied with the flags specified
10490 in the @code{origin} of @var{package} (@pxref{origin Reference}), which
10491 by default includes @code{-p1} (@pxref{patch Directories,,, diffutils,
10492 Comparing and Merging Files}).
10494 As an example, the command below rebuilds Coreutils with the GNU C
10495 Library (glibc) patched with the given patch:
10498 guix build coreutils --with-patch=glibc=./glibc-frob.patch
10501 In this example, glibc itself as well as everything that leads to
10502 Coreutils in the dependency graph is rebuilt.
10504 @cindex upstream, latest version
10505 @item --with-latest=@var{package}
10506 So you like living on the bleeding edge? This option is for you! It
10507 replaces occurrences of @var{package} in the dependency graph with its
10508 latest upstream version, as reported by @command{guix refresh}
10509 (@pxref{Invoking guix refresh}).
10511 It does so by determining the latest upstream release of @var{package}
10512 (if possible), downloading it, and authenticating it @emph{if} it comes
10513 with an OpenPGP signature.
10515 As an example, the command below builds Guix against the latest version
10519 guix build guix --with-latest=guile-json
10522 There are limitations. First, in cases where the tool cannot or does
10523 not know how to authenticate source code, you are at risk of running
10524 malicious code; a warning is emitted in this case. Second, this option
10525 simply changes the source used in the existing package definitions,
10526 which is not always sufficient: there might be additional dependencies
10527 that need to be added, patches to apply, and more generally the quality
10528 assurance work that Guix developers normally do will be missing.
10530 You've been warned! In all the other cases, it's a snappy way to stay
10531 on top. We encourage you to submit patches updating the actual package
10532 definitions once you have successfully tested an upgrade
10533 (@pxref{Contributing}).
10535 @cindex test suite, skipping
10536 @item --without-tests=@var{package}
10537 Build @var{package} without running its tests. This can be useful in
10538 situations where you want to skip the lengthy test suite of a
10539 intermediate package, or if a package's test suite fails in a
10540 non-deterministic fashion. It should be used with care because running
10541 the test suite is a good way to ensure a package is working as intended.
10543 Turning off tests leads to a different store item. Consequently, when
10544 using this option, anything that depends on @var{package} must be
10545 rebuilt, as in this example:
10548 guix install --without-tests=python python-notebook
10551 The command above installs @code{python-notebook} on top of
10552 @code{python} built without running its test suite. To do so, it also
10553 rebuilds everything that depends on @code{python}, including
10554 @code{python-notebook} itself.
10556 Internally, @option{--without-tests} relies on changing the
10557 @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
10558 Systems}). Note that some packages use a customized @code{check} phase
10559 that does not respect a @code{#:tests? #f} setting. Therefore,
10560 @option{--without-tests} has no effect on these packages.
10564 Wondering how to achieve the same effect using Scheme code, for example
10565 in your manifest, or how to write your own package transformation?
10566 @xref{Defining Package Variants}, for an overview of the programming
10567 interfaces available.
10569 @node Additional Build Options
10570 @subsection Additional Build Options
10572 The command-line options presented below are specific to @command{guix
10579 Build quietly, without displaying the build log; this is equivalent to
10580 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
10581 (or similar) and can always be retrieved using the @option{--log-file} option.
10583 @item --file=@var{file}
10584 @itemx -f @var{file}
10585 Build the package, derivation, or other file-like object that the code within
10586 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
10588 As an example, @var{file} might contain a package definition like this
10589 (@pxref{Defining Packages}):
10592 @include package-hello.scm
10595 The @var{file} may also contain a JSON representation of one or more
10596 package definitions. Running @code{guix build -f} on @file{hello.json}
10597 with the following contents would result in building the packages
10598 @code{myhello} and @code{greeter}:
10601 @verbatiminclude package-hello.json
10604 @item --manifest=@var{manifest}
10605 @itemx -m @var{manifest}
10606 Build all packages listed in the given @var{manifest}
10607 (@pxref{profile-manifest, @option{--manifest}}).
10609 @item --expression=@var{expr}
10610 @itemx -e @var{expr}
10611 Build the package or derivation @var{expr} evaluates to.
10613 For example, @var{expr} may be @code{(@@ (gnu packages guile)
10614 guile-1.8)}, which unambiguously designates this specific variant of
10615 version 1.8 of Guile.
10617 Alternatively, @var{expr} may be a G-expression, in which case it is used
10618 as a build program passed to @code{gexp->derivation}
10619 (@pxref{G-Expressions}).
10621 Lastly, @var{expr} may refer to a zero-argument monadic procedure
10622 (@pxref{The Store Monad}). The procedure must return a derivation as a
10623 monadic value, which is then passed through @code{run-with-store}.
10627 Build the source derivations of the packages, rather than the packages
10630 For instance, @code{guix build -S gcc} returns something like
10631 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
10634 The returned source tarball is the result of applying any patches and
10635 code snippets specified in the package @code{origin} (@pxref{Defining
10638 @cindex source, verification
10639 As with other derivations, the result of building a source derivation
10640 can be verified using the @option{--check} option (@pxref{build-check}).
10641 This is useful to validate that a (potentially already built or
10642 substituted, thus cached) package source matches against its declared
10645 Note that @command{guix build -S} compiles the sources only of the
10646 specified packages. They do not include the sources of statically
10647 linked dependencies and by themselves are insufficient for reproducing
10651 Fetch and return the source of @var{package-or-derivation} and all their
10652 dependencies, recursively. This is a handy way to obtain a local copy
10653 of all the source code needed to build @var{packages}, allowing you to
10654 eventually build them even without network access. It is an extension
10655 of the @option{--source} option and can accept one of the following
10656 optional argument values:
10660 This value causes the @option{--sources} option to behave in the same way
10661 as the @option{--source} option.
10664 Build the source derivations of all packages, including any source that
10665 might be listed as @code{inputs}. This is the default value.
10668 $ guix build --sources tzdata
10669 The following derivations will be built:
10670 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
10671 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
10675 Build the source derivations of all packages, as well of all transitive
10676 inputs to the packages. This can be used e.g.@: to
10677 prefetch package source for later offline building.
10680 $ guix build --sources=transitive tzdata
10681 The following derivations will be built:
10682 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
10683 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
10684 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
10685 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
10686 /gnu/store/@dots{}-make-4.1.tar.xz.drv
10687 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
10693 @item --system=@var{system}
10694 @itemx -s @var{system}
10695 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
10696 the system type of the build host. The @command{guix build} command allows
10697 you to repeat this option several times, in which case it builds for all the
10698 specified systems; other commands ignore extraneous @option{-s} options.
10701 The @option{--system} flag is for @emph{native} compilation and must not
10702 be confused with cross-compilation. See @option{--target} below for
10703 information on cross-compilation.
10706 An example use of this is on Linux-based systems, which can emulate
10707 different personalities. For instance, passing
10708 @option{--system=i686-linux} on an @code{x86_64-linux} system or
10709 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
10710 you to build packages in a complete 32-bit environment.
10713 Building for an @code{armhf-linux} system is unconditionally enabled on
10714 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
10715 allow for this functionality, notably the ThunderX.
10718 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
10719 is enabled (@pxref{Virtualization Services,
10720 @code{qemu-binfmt-service-type}}), you can build for any system for
10721 which a QEMU @code{binfmt_misc} handler is installed.
10723 Builds for a system other than that of the machine you are using can
10724 also be offloaded to a remote machine of the right architecture.
10725 @xref{Daemon Offload Setup}, for more information on offloading.
10727 @item --target=@var{triplet}
10728 @cindex cross-compilation
10729 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
10730 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
10731 configuration triplets,, autoconf, Autoconf}).
10733 @anchor{build-check}
10735 @cindex determinism, checking
10736 @cindex reproducibility, checking
10737 Rebuild @var{package-or-derivation}, which are already available in the
10738 store, and raise an error if the build results are not bit-for-bit
10741 This mechanism allows you to check whether previously installed
10742 substitutes are genuine (@pxref{Substitutes}), or whether the build result
10743 of a package is deterministic. @xref{Invoking guix challenge}, for more
10744 background information and tools.
10746 When used in conjunction with @option{--keep-failed}, the differing
10747 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
10748 This makes it easy to look for differences between the two results.
10751 @cindex repairing store items
10752 @cindex corruption, recovering from
10753 Attempt to repair the specified store items, if they are corrupt, by
10754 re-downloading or rebuilding them.
10756 This operation is not atomic and thus restricted to @code{root}.
10758 @item --derivations
10760 Return the derivation paths, not the output paths, of the given
10763 @item --root=@var{file}
10764 @itemx -r @var{file}
10765 @cindex GC roots, adding
10766 @cindex garbage collector roots, adding
10767 Make @var{file} a symlink to the result, and register it as a garbage
10770 Consequently, the results of this @command{guix build} invocation are
10771 protected from garbage collection until @var{file} is removed. When
10772 that option is omitted, build results are eligible for garbage
10773 collection as soon as the build completes. @xref{Invoking guix gc}, for
10777 @cindex build logs, access
10778 Return the build log file names or URLs for the given
10779 @var{package-or-derivation}, or raise an error if build logs are
10782 This works regardless of how packages or derivations are specified. For
10783 instance, the following invocations are equivalent:
10786 guix build --log-file `guix build -d guile`
10787 guix build --log-file `guix build guile`
10788 guix build --log-file guile
10789 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
10792 If a log is unavailable locally, and unless @option{--no-substitutes} is
10793 passed, the command looks for a corresponding log on one of the
10794 substitute servers (as specified with @option{--substitute-urls}).
10796 So for instance, imagine you want to see the build log of GDB on MIPS,
10797 but you are actually on an @code{x86_64} machine:
10800 $ guix build --log-file gdb -s aarch64-linux
10801 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
10804 You can freely access a huge library of build logs!
10807 @node Debugging Build Failures
10808 @subsection Debugging Build Failures
10810 @cindex build failures, debugging
10811 When defining a new package (@pxref{Defining Packages}), you will
10812 probably find yourself spending some time debugging and tweaking the
10813 build until it succeeds. To do that, you need to operate the build
10814 commands yourself in an environment as close as possible to the one the
10817 To that end, the first thing to do is to use the @option{--keep-failed}
10818 or @option{-K} option of @command{guix build}, which will keep the
10819 failed build tree in @file{/tmp} or whatever directory you specified as
10820 @env{TMPDIR} (@pxref{Invoking guix build, @option{--keep-failed}}).
10822 From there on, you can @command{cd} to the failed build tree and source
10823 the @file{environment-variables} file, which contains all the
10824 environment variable definitions that were in place when the build
10825 failed. So let's say you're debugging a build failure in package
10826 @code{foo}; a typical session would look like this:
10829 $ guix build foo -K
10830 @dots{} @i{build fails}
10831 $ cd /tmp/guix-build-foo.drv-0
10832 $ source ./environment-variables
10836 Now, you can invoke commands as if you were the daemon (almost) and
10837 troubleshoot your build process.
10839 Sometimes it happens that, for example, a package's tests pass when you
10840 run them manually but they fail when the daemon runs them. This can
10841 happen because the daemon runs builds in containers where, unlike in our
10842 environment above, network access is missing, @file{/bin/sh} does not
10843 exist, etc. (@pxref{Build Environment Setup}).
10845 In such cases, you may need to run inspect the build process from within
10846 a container similar to the one the build daemon creates:
10849 $ guix build -K foo
10851 $ cd /tmp/guix-build-foo.drv-0
10852 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
10853 [env]# source ./environment-variables
10857 Here, @command{guix environment -C} creates a container and spawns a new
10858 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
10859 strace gdb} part adds the @command{strace} and @command{gdb} commands to
10860 the container, which you may find handy while debugging. The
10861 @option{--no-grafts} option makes sure we get the exact same
10862 environment, with ungrafted packages (@pxref{Security Updates}, for more
10865 To get closer to a container like that used by the build daemon, we can
10866 remove @file{/bin/sh}:
10872 (Don't worry, this is harmless: this is all happening in the throw-away
10873 container created by @command{guix environment}.)
10875 The @command{strace} command is probably not in the search path, but we
10879 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
10882 In this way, not only you will have reproduced the environment variables
10883 the daemon uses, you will also be running the build process in a container
10884 similar to the one the daemon uses.
10887 @node Invoking guix edit
10888 @section Invoking @command{guix edit}
10890 @cindex @command{guix edit}
10891 @cindex package definition, editing
10892 So many packages, so many source files! The @command{guix edit} command
10893 facilitates the life of users and packagers by pointing their editor at
10894 the source file containing the definition of the specified packages.
10898 guix edit gcc@@4.9 vim
10902 launches the program specified in the @env{VISUAL} or in the
10903 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
10906 If you are using a Guix Git checkout (@pxref{Building from Git}), or
10907 have created your own packages on @env{GUIX_PACKAGE_PATH}
10908 (@pxref{Package Modules}), you will be able to edit the package
10909 recipes. In other cases, you will be able to examine the read-only recipes
10910 for packages currently in the store.
10912 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
10913 @option{--load-path=@var{directory}} (or in short @option{-L
10914 @var{directory}}) allows you to add @var{directory} to the front of the
10915 package module search path and so make your own packages visible.
10917 @node Invoking guix download
10918 @section Invoking @command{guix download}
10920 @cindex @command{guix download}
10921 @cindex downloading package sources
10922 When writing a package definition, developers typically need to download
10923 a source tarball, compute its SHA256 hash, and write that
10924 hash in the package definition (@pxref{Defining Packages}). The
10925 @command{guix download} tool helps with this task: it downloads a file
10926 from the given URI, adds it to the store, and prints both its file name
10927 in the store and its SHA256 hash.
10929 The fact that the downloaded file is added to the store saves bandwidth:
10930 when the developer eventually tries to build the newly defined package
10931 with @command{guix build}, the source tarball will not have to be
10932 downloaded again because it is already in the store. It is also a
10933 convenient way to temporarily stash files, which may be deleted
10934 eventually (@pxref{Invoking guix gc}).
10936 The @command{guix download} command supports the same URIs as used in
10937 package definitions. In particular, it supports @code{mirror://} URIs.
10938 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
10939 Guile bindings for GnuTLS are available in the user's environment; when
10940 they are not available, an error is raised. @xref{Guile Preparations,
10941 how to install the GnuTLS bindings for Guile,, gnutls-guile,
10942 GnuTLS-Guile}, for more information.
10944 @command{guix download} verifies HTTPS server certificates by loading
10945 the certificates of X.509 authorities from the directory pointed to by
10946 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
10947 Certificates}), unless @option{--no-check-certificate} is used.
10949 The following options are available:
10952 @item --hash=@var{algorithm}
10953 @itemx -H @var{algorithm}
10954 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
10955 hash}, for more information.
10957 @item --format=@var{fmt}
10958 @itemx -f @var{fmt}
10959 Write the hash in the format specified by @var{fmt}. For more
10960 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
10962 @item --no-check-certificate
10963 Do not validate the X.509 certificates of HTTPS servers.
10965 When using this option, you have @emph{absolutely no guarantee} that you
10966 are communicating with the authentic server responsible for the given
10967 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
10969 @item --output=@var{file}
10970 @itemx -o @var{file}
10971 Save the downloaded file to @var{file} instead of adding it to the
10975 @node Invoking guix hash
10976 @section Invoking @command{guix hash}
10978 @cindex @command{guix hash}
10979 The @command{guix hash} command computes the hash of a file.
10980 It is primarily a convenience tool for anyone contributing to the
10981 distribution: it computes the cryptographic hash of a file, which can be
10982 used in the definition of a package (@pxref{Defining Packages}).
10984 The general syntax is:
10987 guix hash @var{option} @var{file}
10990 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
10991 hash of data read from standard input. @command{guix hash} has the
10996 @item --hash=@var{algorithm}
10997 @itemx -H @var{algorithm}
10998 Compute a hash using the specified @var{algorithm}, @code{sha256} by
11001 @var{algorithm} must the name of a cryptographic hash algorithm
11002 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
11003 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
11004 Reference Manual}).
11006 @item --format=@var{fmt}
11007 @itemx -f @var{fmt}
11008 Write the hash in the format specified by @var{fmt}.
11010 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
11011 (@code{hex} and @code{hexadecimal} can be used as well).
11013 If the @option{--format} option is not specified, @command{guix hash}
11014 will output the hash in @code{nix-base32}. This representation is used
11015 in the definitions of packages.
11019 Compute the hash on @var{file} recursively.
11021 In this case, the hash is computed on an archive containing @var{file},
11022 including its children if it is a directory. Some of the metadata of
11023 @var{file} is part of the archive; for instance, when @var{file} is a
11024 regular file, the hash is different depending on whether @var{file} is
11025 executable or not. Metadata such as time stamps has no impact on the
11026 hash (@pxref{Invoking guix archive}).
11027 @c FIXME: Replace xref above with xref to an ``Archive'' section when
11030 @item --exclude-vcs
11032 When combined with @option{--recursive}, exclude version control system
11033 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
11036 As an example, here is how you would compute the hash of a Git checkout,
11037 which is useful when using the @code{git-fetch} method (@pxref{origin
11041 $ git clone http://example.org/foo.git
11047 @node Invoking guix import
11048 @section Invoking @command{guix import}
11050 @cindex importing packages
11051 @cindex package import
11052 @cindex package conversion
11053 @cindex Invoking @command{guix import}
11054 The @command{guix import} command is useful for people who would like to
11055 add a package to the distribution with as little work as
11056 possible---a legitimate demand. The command knows of a few
11057 repositories from which it can ``import'' package metadata. The result
11058 is a package definition, or a template thereof, in the format we know
11059 (@pxref{Defining Packages}).
11061 The general syntax is:
11064 guix import @var{importer} @var{options}@dots{}
11067 @var{importer} specifies the source from which to import package
11068 metadata, and @var{options} specifies a package identifier and other
11069 options specific to @var{importer}.
11071 Some of the importers rely on the ability to run the @command{gpgv} command.
11072 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
11075 Currently, the available ``importers'' are:
11079 Import metadata for the given GNU package. This provides a template
11080 for the latest version of that GNU package, including the hash of its
11081 source tarball, and its canonical synopsis and description.
11083 Additional information such as the package dependencies and its
11084 license needs to be figured out manually.
11086 For example, the following command returns a package definition for
11090 guix import gnu hello
11093 Specific command-line options are:
11096 @item --key-download=@var{policy}
11097 As for @command{guix refresh}, specify the policy to handle missing
11098 OpenPGP keys when verifying the package signature. @xref{Invoking guix
11099 refresh, @option{--key-download}}.
11104 Import metadata from the @uref{https://pypi.python.org/, Python Package
11105 Index}. Information is taken from the JSON-formatted description
11106 available at @code{pypi.python.org} and usually includes all the relevant
11107 information, including package dependencies. For maximum efficiency, it
11108 is recommended to install the @command{unzip} utility, so that the
11109 importer can unzip Python wheels and gather data from them.
11111 The command below imports metadata for the @code{itsdangerous} Python
11115 guix import pypi itsdangerous
11121 Traverse the dependency graph of the given upstream package recursively
11122 and generate package expressions for all those packages that are not yet
11128 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
11129 is taken from the JSON-formatted description available at
11130 @code{rubygems.org} and includes most relevant information, including
11131 runtime dependencies. There are some caveats, however. The metadata
11132 doesn't distinguish between synopses and descriptions, so the same string
11133 is used for both fields. Additionally, the details of non-Ruby
11134 dependencies required to build native extensions is unavailable and left
11135 as an exercise to the packager.
11137 The command below imports metadata for the @code{rails} Ruby package:
11140 guix import gem rails
11146 Traverse the dependency graph of the given upstream package recursively
11147 and generate package expressions for all those packages that are not yet
11153 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
11154 Information is taken from the JSON-formatted metadata provided through
11155 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
11156 relevant information, such as module dependencies. License information
11157 should be checked closely. If Perl is available in the store, then the
11158 @code{corelist} utility will be used to filter core modules out of the
11159 list of dependencies.
11161 The command command below imports metadata for the Acme::Boolean Perl
11165 guix import cpan Acme::Boolean
11170 @cindex Bioconductor
11171 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
11172 central repository for the @uref{https://r-project.org, GNU@tie{}R
11173 statistical and graphical environment}.
11175 Information is extracted from the @file{DESCRIPTION} file of the package.
11177 The command command below imports metadata for the Cairo R package:
11180 guix import cran Cairo
11183 When @option{--recursive} is added, the importer will traverse the
11184 dependency graph of the given upstream package recursively and generate
11185 package expressions for all those packages that are not yet in Guix.
11187 When @option{--style=specification} is added, the importer will generate
11188 package definitions whose inputs are package specifications instead of
11189 references to package variables. This is useful when generated package
11190 definitions are to be appended to existing user modules, as the list of
11191 used package modules need not be changed. The default is
11192 @option{--style=variable}.
11194 When @option{--archive=bioconductor} is added, metadata is imported from
11195 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
11196 packages for the analysis and comprehension of high-throughput
11197 genomic data in bioinformatics.
11199 Information is extracted from the @file{DESCRIPTION} file contained in the
11202 The command below imports metadata for the GenomicRanges R package:
11205 guix import cran --archive=bioconductor GenomicRanges
11208 Finally, you can also import R packages that have not yet been published on
11209 CRAN or Bioconductor as long as they are in a git repository. Use
11210 @option{--archive=git} followed by the URL of the git repository:
11213 guix import cran --archive=git https://github.com/immunogenomics/harmony
11219 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
11220 comprehensive TeX archive network for TeX packages that are part of the
11221 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
11223 Information about the package is obtained through the XML API provided
11224 by CTAN, while the source code is downloaded from the SVN repository of
11225 the Tex Live project. This is done because the CTAN does not keep
11226 versioned archives.
11228 The command command below imports metadata for the @code{fontspec}
11232 guix import texlive fontspec
11235 When @option{--archive=@var{directory}} is added, the source code is
11236 downloaded not from the @file{latex} sub-directory of the
11237 @file{texmf-dist/source} tree in the TeX Live SVN repository, but from
11238 the specified sibling @var{directory} under the same root.
11240 The command below imports metadata for the @code{ifxetex} package from
11241 CTAN while fetching the sources from the directory
11242 @file{texmf/source/generic}:
11245 guix import texlive --archive=generic ifxetex
11249 @cindex JSON, import
11250 Import package metadata from a local JSON file. Consider the following
11251 example package definition in JSON format:
11257 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
11258 "build-system": "gnu",
11259 "home-page": "https://www.gnu.org/software/hello/",
11260 "synopsis": "Hello, GNU world: An example GNU package",
11261 "description": "GNU Hello prints a greeting.",
11262 "license": "GPL-3.0+",
11263 "native-inputs": ["gettext"]
11267 The field names are the same as for the @code{<package>} record
11268 (@xref{Defining Packages}). References to other packages are provided
11269 as JSON lists of quoted package specification strings such as
11270 @code{guile} or @code{guile@@2.0}.
11272 The importer also supports a more explicit source definition using the
11273 common fields for @code{<origin>} records:
11279 "method": "url-fetch",
11280 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
11282 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
11289 The command below reads metadata from the JSON file @code{hello.json}
11290 and outputs a package expression:
11293 guix import json hello.json
11297 Import metadata from a local copy of the source of the
11298 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
11299 relies on the @command{nix-instantiate} command of
11300 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
11301 typically written in a mixture of Nix-language and Bash code. This
11302 command only imports the high-level package structure that is written in
11303 the Nix language. It normally includes all the basic fields of a
11304 package definition.
11306 When importing a GNU package, the synopsis and descriptions are replaced
11307 by their canonical upstream variant.
11309 Usually, you will first need to do:
11312 export NIX_REMOTE=daemon
11316 so that @command{nix-instantiate} does not try to open the Nix database.
11318 As an example, the command below imports the package definition of
11319 LibreOffice (more precisely, it imports the definition of the package
11320 bound to the @code{libreoffice} top-level attribute):
11323 guix import nix ~/path/to/nixpkgs libreoffice
11328 Import metadata from the Haskell community's central package archive
11329 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
11330 Cabal files and includes all the relevant information, including package
11333 Specific command-line options are:
11338 Read a Cabal file from standard input.
11339 @item --no-test-dependencies
11341 Do not include dependencies required only by the test suites.
11342 @item --cabal-environment=@var{alist}
11343 @itemx -e @var{alist}
11344 @var{alist} is a Scheme alist defining the environment in which the
11345 Cabal conditionals are evaluated. The accepted keys are: @code{os},
11346 @code{arch}, @code{impl} and a string representing the name of a flag.
11347 The value associated with a flag has to be either the symbol
11348 @code{true} or @code{false}. The value associated with other keys
11349 has to conform to the Cabal file format definition. The default value
11350 associated with the keys @code{os}, @code{arch} and @code{impl} is
11351 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
11354 Traverse the dependency graph of the given upstream package recursively
11355 and generate package expressions for all those packages that are not yet
11359 The command below imports metadata for the latest version of the
11360 HTTP Haskell package without including test dependencies and
11361 specifying the value of the flag @samp{network-uri} as @code{false}:
11364 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
11367 A specific package version may optionally be specified by following the
11368 package name by an at-sign and a version number as in the following example:
11371 guix import hackage mtl@@2.1.3.1
11376 The @code{stackage} importer is a wrapper around the @code{hackage} one.
11377 It takes a package name, looks up the package version included in a
11378 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
11379 release and uses the @code{hackage} importer to retrieve its metadata.
11380 Note that it is up to you to select an LTS release compatible with the
11381 GHC compiler used by Guix.
11383 Specific command-line options are:
11386 @item --no-test-dependencies
11388 Do not include dependencies required only by the test suites.
11389 @item --lts-version=@var{version}
11390 @itemx -l @var{version}
11391 @var{version} is the desired LTS release version. If omitted the latest
11395 Traverse the dependency graph of the given upstream package recursively
11396 and generate package expressions for all those packages that are not yet
11400 The command below imports metadata for the HTTP Haskell package
11401 included in the LTS Stackage release version 7.18:
11404 guix import stackage --lts-version=7.18 HTTP
11409 Import metadata from an Emacs Lisp Package Archive (ELPA) package
11410 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
11412 Specific command-line options are:
11415 @item --archive=@var{repo}
11416 @itemx -a @var{repo}
11417 @var{repo} identifies the archive repository from which to retrieve the
11418 information. Currently the supported repositories and their identifiers
11422 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
11423 identifier. This is the default.
11425 Packages from @code{elpa.gnu.org} are signed with one of the keys
11426 contained in the GnuPG keyring at
11427 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
11428 @code{emacs} package (@pxref{Package Installation, ELPA package
11429 signatures,, emacs, The GNU Emacs Manual}).
11432 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
11433 @code{melpa-stable} identifier.
11436 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
11442 Traverse the dependency graph of the given upstream package recursively
11443 and generate package expressions for all those packages that are not yet
11449 Import metadata from the crates.io Rust package repository
11450 @uref{https://crates.io, crates.io}, as in this example:
11453 guix import crate blake2-rfc
11456 The crate importer also allows you to specify a version string:
11459 guix import crate constant-time-eq@@0.1.0
11462 Additional options include:
11467 Traverse the dependency graph of the given upstream package recursively
11468 and generate package expressions for all those packages that are not yet
11475 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
11476 repository used by the OCaml community.
11478 Additional options include:
11483 Traverse the dependency graph of the given upstream package recursively
11484 and generate package expressions for all those packages that are not yet
11487 Select the given repository (a repository name). Possible values include:
11489 @item @code{opam}, the default opam repository,
11490 @item @code{coq} or @code{coq-released}, the stable repository for coq packages,
11491 @item @code{coq-core-dev}, the repository that contains development versions of coq,
11492 @item @code{coq-extra-dev}, the repository that contains development versions
11498 The structure of the @command{guix import} code is modular. It would be
11499 useful to have more importers for other package formats, and your help
11500 is welcome here (@pxref{Contributing}).
11502 @node Invoking guix refresh
11503 @section Invoking @command{guix refresh}
11505 @cindex @command {guix refresh}
11506 The primary audience of the @command{guix refresh} command is developers
11507 of the GNU software distribution. By default, it reports any packages
11508 provided by the distribution that are outdated compared to the latest
11509 upstream version, like this:
11513 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
11514 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
11517 Alternatively, one can specify packages to consider, in which case a
11518 warning is emitted for packages that lack an updater:
11521 $ guix refresh coreutils guile guile-ssh
11522 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
11523 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
11526 @command{guix refresh} browses the upstream repository of each package and determines
11527 the highest version number of the releases therein. The command
11528 knows how to update specific types of packages: GNU packages, ELPA
11529 packages, etc.---see the documentation for @option{--type} below. There
11530 are many packages, though, for which it lacks a method to determine
11531 whether a new upstream release is available. However, the mechanism is
11532 extensible, so feel free to get in touch with us to add a new method!
11537 Consider the packages specified, and all the packages upon which they depend.
11540 $ guix refresh --recursive coreutils
11541 gnu/packages/acl.scm:35:2: warning: no updater for acl
11542 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
11543 gnu/packages/xml.scm:68:2: warning: no updater for expat
11544 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
11550 Sometimes the upstream name differs from the package name used in Guix,
11551 and @command{guix refresh} needs a little help. Most updaters honor the
11552 @code{upstream-name} property in package definitions, which can be used
11556 (define-public network-manager
11558 (name "network-manager")
11560 (properties '((upstream-name . "NetworkManager")))))
11563 When passed @option{--update}, it modifies distribution source files to
11564 update the version numbers and source tarball hashes of those package
11565 recipes (@pxref{Defining Packages}). This is achieved by downloading
11566 each package's latest source tarball and its associated OpenPGP
11567 signature, authenticating the downloaded tarball against its signature
11568 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
11569 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
11572 key used to sign the tarball is missing from the user's keyring, an
11573 attempt is made to automatically retrieve it from a public key server;
11574 when this is successful, the key is added to the user's keyring; otherwise,
11575 @command{guix refresh} reports an error.
11577 The following options are supported:
11581 @item --expression=@var{expr}
11582 @itemx -e @var{expr}
11583 Consider the package @var{expr} evaluates to.
11585 This is useful to precisely refer to a package, as in this example:
11588 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
11591 This command lists the dependents of the ``final'' libc (essentially all
11596 Update distribution source files (package recipes) in place. This is
11597 usually run from a checkout of the Guix source tree (@pxref{Running
11598 Guix Before It Is Installed}):
11601 $ ./pre-inst-env guix refresh -s non-core -u
11604 @xref{Defining Packages}, for more information on package definitions.
11606 @item --select=[@var{subset}]
11607 @itemx -s @var{subset}
11608 Select all the packages in @var{subset}, one of @code{core} or
11611 The @code{core} subset refers to all the packages at the core of the
11612 distribution---i.e., packages that are used to build ``everything
11613 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
11614 changing one of these packages in the distribution entails a rebuild of
11615 all the others. Thus, such updates are an inconvenience to users in
11616 terms of build time or bandwidth used to achieve the upgrade.
11618 The @code{non-core} subset refers to the remaining packages. It is
11619 typically useful in cases where an update of the core packages would be
11622 @item --manifest=@var{file}
11623 @itemx -m @var{file}
11624 Select all the packages from the manifest in @var{file}. This is useful to
11625 check if any packages of the user manifest can be updated.
11627 @item --type=@var{updater}
11628 @itemx -t @var{updater}
11629 Select only packages handled by @var{updater} (may be a comma-separated
11630 list of updaters). Currently, @var{updater} may be one of:
11634 the updater for GNU packages;
11636 the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
11638 the updater for GNOME packages;
11640 the updater for KDE packages;
11642 the updater for X.org packages;
11644 the updater for packages hosted on kernel.org;
11646 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
11648 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
11650 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
11652 the updater for @uref{https://www.cpan.org/, CPAN} packages;
11654 the updater for @uref{https://pypi.python.org, PyPI} packages.
11656 the updater for @uref{https://rubygems.org, RubyGems} packages.
11658 the updater for @uref{https://github.com, GitHub} packages.
11660 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
11662 the updater for @uref{https://www.stackage.org, Stackage} packages.
11664 the updater for @uref{https://crates.io, Crates} packages.
11666 the updater for @uref{https://launchpad.net, Launchpad} packages.
11669 For instance, the following command only checks for updates of Emacs
11670 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
11673 $ guix refresh --type=elpa,cran
11674 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
11675 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
11680 In addition, @command{guix refresh} can be passed one or more package
11681 names, as in this example:
11684 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
11688 The command above specifically updates the @code{emacs} and
11689 @code{idutils} packages. The @option{--select} option would have no
11690 effect in this case.
11692 When considering whether to upgrade a package, it is sometimes
11693 convenient to know which packages would be affected by the upgrade and
11694 should be checked for compatibility. For this the following option may
11695 be used when passing @command{guix refresh} one or more package names:
11699 @item --list-updaters
11701 List available updaters and exit (see @option{--type} above).
11703 For each updater, display the fraction of packages it covers; at the
11704 end, display the fraction of packages covered by all these updaters.
11706 @item --list-dependent
11708 List top-level dependent packages that would need to be rebuilt as a
11709 result of upgrading one or more packages.
11711 @xref{Invoking guix graph, the @code{reverse-package} type of
11712 @command{guix graph}}, for information on how to visualize the list of
11713 dependents of a package.
11717 Be aware that the @option{--list-dependent} option only
11718 @emph{approximates} the rebuilds that would be required as a result of
11719 an upgrade. More rebuilds might be required under some circumstances.
11722 $ guix refresh --list-dependent flex
11723 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
11724 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
11727 The command above lists a set of packages that could be built to check
11728 for compatibility with an upgraded @code{flex} package.
11732 @item --list-transitive
11733 List all the packages which one or more packages depend upon.
11736 $ guix refresh --list-transitive flex
11737 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
11738 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{}
11743 The command above lists a set of packages which, when changed, would cause
11744 @code{flex} to be rebuilt.
11746 The following options can be used to customize GnuPG operation:
11750 @item --gpg=@var{command}
11751 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
11752 for in @code{$PATH}.
11754 @item --keyring=@var{file}
11755 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
11756 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
11757 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
11758 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
11759 information on a tool to manipulate keybox files).
11761 When this option is omitted, @command{guix refresh} uses
11762 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
11763 signing keys. OpenPGP signatures are checked against keys from this keyring;
11764 missing keys are downloaded to this keyring as well (see
11765 @option{--key-download} below).
11767 You can export keys from your default GPG keyring into a keybox file using
11768 commands like this one:
11771 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
11774 Likewise, you can fetch keys to a specific keybox file like this:
11777 gpg --no-default-keyring --keyring mykeyring.kbx \
11778 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
11781 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
11782 Privacy Guard}, for more information on GPG's @option{--keyring} option.
11784 @item --key-download=@var{policy}
11785 Handle missing OpenPGP keys according to @var{policy}, which may be one
11790 Always download missing OpenPGP keys from the key server, and add them
11791 to the user's GnuPG keyring.
11794 Never try to download missing OpenPGP keys. Instead just bail out.
11797 When a package signed with an unknown OpenPGP key is encountered, ask
11798 the user whether to download it or not. This is the default behavior.
11801 @item --key-server=@var{host}
11802 Use @var{host} as the OpenPGP key server when importing a public key.
11804 @item --load-path=@var{directory}
11805 Add @var{directory} to the front of the package module search path
11806 (@pxref{Package Modules}).
11808 This allows users to define their own packages and make them visible to
11809 the command-line tools.
11813 The @code{github} updater uses the
11814 @uref{https://developer.github.com/v3/, GitHub API} to query for new
11815 releases. When used repeatedly e.g.@: when refreshing all packages,
11816 GitHub will eventually refuse to answer any further API requests. By
11817 default 60 API requests per hour are allowed, and a full refresh on all
11818 GitHub packages in Guix requires more than this. Authentication with
11819 GitHub through the use of an API token alleviates these limits. To use
11820 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
11821 token procured from @uref{https://github.com/settings/tokens} or
11825 @node Invoking guix lint
11826 @section Invoking @command{guix lint}
11828 @cindex @command{guix lint}
11829 @cindex package, checking for errors
11830 The @command{guix lint} command is meant to help package developers avoid
11831 common errors and use a consistent style. It runs a number of checks on
11832 a given set of packages in order to find common mistakes in their
11833 definitions. Available @dfn{checkers} include (see
11834 @option{--list-checkers} for a complete list):
11839 Validate certain typographical and stylistic rules about package
11840 descriptions and synopses.
11842 @item inputs-should-be-native
11843 Identify inputs that should most likely be native inputs.
11849 @itemx source-file-name
11850 Probe @code{home-page} and @code{source} URLs and report those that are
11851 invalid. Suggest a @code{mirror://} URL when applicable. If the
11852 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
11853 URL@. Check that the source file name is meaningful, e.g.@: is not just a
11854 version number or ``git-checkout'', without a declared @code{file-name}
11855 (@pxref{origin Reference}).
11857 @item source-unstable-tarball
11858 Parse the @code{source} URL to determine if a tarball from GitHub is
11859 autogenerated or if it is a release tarball. Unfortunately GitHub's
11860 autogenerated tarballs are sometimes regenerated.
11863 Check that the derivation of the given packages can be successfully
11864 computed for all the supported systems (@pxref{Derivations}).
11866 @item profile-collisions
11867 Check whether installing the given packages in a profile would lead to
11868 collisions. Collisions occur when several packages with the same name
11869 but a different version or a different store file name are propagated.
11870 @xref{package Reference, @code{propagated-inputs}}, for more information
11871 on propagated inputs.
11874 @cindex Software Heritage, source code archive
11875 @cindex archival of source code, Software Heritage
11876 Checks whether the package's source code is archived at
11877 @uref{https://www.softwareheritage.org, Software Heritage}.
11879 When the source code that is not archived comes from a version-control system
11880 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
11881 ``save'' request so that it eventually archives it. This ensures that the
11882 source will remain available in the long term, and that Guix can fall back to
11883 Software Heritage should the source code disappear from its original host.
11884 The status of recent ``save'' requests can be
11885 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
11887 When source code is a tarball obtained with @code{url-fetch}, simply print a
11888 message when it is not archived. As of this writing, Software Heritage does
11889 not allow requests to save arbitrary tarballs; we are working on ways to
11890 ensure that non-VCS source code is also archived.
11893 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
11894 request rate per IP address}. When the limit is reached, @command{guix lint}
11895 prints a message and the @code{archival} checker stops doing anything until
11896 that limit has been reset.
11899 @cindex security vulnerabilities
11900 @cindex CVE, Common Vulnerabilities and Exposures
11901 Report known vulnerabilities found in the Common Vulnerabilities and
11902 Exposures (CVE) databases of the current and past year
11903 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
11906 To view information about a particular vulnerability, visit pages such as:
11910 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
11912 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
11916 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
11917 @code{CVE-2015-7554}.
11919 Package developers can specify in package recipes the
11920 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
11921 name and version of the package when they differ from the name or version
11922 that Guix uses, as in this example:
11928 ;; CPE calls this package "grub2".
11929 (properties '((cpe-name . "grub2")
11930 (cpe-version . "2.3"))))
11933 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
11934 Some entries in the CVE database do not specify which version of a
11935 package they apply to, and would thus ``stick around'' forever. Package
11936 developers who found CVE alerts and verified they can be ignored can
11937 declare them as in this example:
11943 ;; These CVEs no longer apply and can be safely ignored.
11944 (properties `((lint-hidden-cve . ("CVE-2011-0433"
11947 "CVE-2011-5244")))))
11951 Warn about obvious source code formatting issues: trailing white space,
11952 use of tabulations, etc.
11955 The general syntax is:
11958 guix lint @var{options} @var{package}@dots{}
11961 If no package is given on the command line, then all packages are checked.
11962 The @var{options} may be zero or more of the following:
11965 @item --list-checkers
11967 List and describe all the available checkers that will be run on packages
11972 Only enable the checkers specified in a comma-separated list using the
11973 names returned by @option{--list-checkers}.
11977 Only disable the checkers specified in a comma-separated list using the
11978 names returned by @option{--list-checkers}.
11982 Only enable the checkers that do not depend on Internet access.
11984 @item --load-path=@var{directory}
11985 @itemx -L @var{directory}
11986 Add @var{directory} to the front of the package module search path
11987 (@pxref{Package Modules}).
11989 This allows users to define their own packages and make them visible to
11990 the command-line tools.
11994 @node Invoking guix size
11995 @section Invoking @command{guix size}
11998 @cindex package size
12000 @cindex @command{guix size}
12001 The @command{guix size} command helps package developers profile the
12002 disk usage of packages. It is easy to overlook the impact of an
12003 additional dependency added to a package, or the impact of using a
12004 single output for a package that could easily be split (@pxref{Packages
12005 with Multiple Outputs}). Such are the typical issues that
12006 @command{guix size} can highlight.
12008 The command can be passed one or more package specifications
12009 such as @code{gcc@@4.8}
12010 or @code{guile:debug}, or a file name in the store. Consider this
12014 $ guix size coreutils
12015 store item total self
12016 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
12017 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
12018 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
12019 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
12020 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
12021 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
12022 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
12023 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
12028 The store items listed here constitute the @dfn{transitive closure} of
12029 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
12030 would be returned by:
12033 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
12036 Here the output shows three columns next to store items. The first column,
12037 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
12038 the store item---that is, its own size plus the size of all its
12039 dependencies. The next column, labeled ``self'', shows the size of the
12040 item itself. The last column shows the ratio of the size of the item
12041 itself to the space occupied by all the items listed here.
12043 In this example, we see that the closure of Coreutils weighs in at
12044 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
12045 libraries. (That libc and GCC's libraries represent a large fraction of
12046 the closure is not a problem @i{per se} because they are always available
12047 on the system anyway.)
12049 Since the command also accepts store file names, assessing the size of
12050 a build result is straightforward:
12053 guix size $(guix system build config.scm)
12056 When the package(s) passed to @command{guix size} are available in the
12057 store@footnote{More precisely, @command{guix size} looks for the
12058 @emph{ungrafted} variant of the given package(s), as returned by
12059 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
12060 for information on grafts.}, @command{guix size} queries the daemon to determine its
12061 dependencies, and measures its size in the store, similar to @command{du
12062 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
12065 When the given packages are @emph{not} in the store, @command{guix size}
12066 reports information based on the available substitutes
12067 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
12068 store items that are not even on disk, only available remotely.
12070 You can also specify several package names:
12073 $ guix size coreutils grep sed bash
12074 store item total self
12075 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
12076 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
12077 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
12078 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
12084 In this example we see that the combination of the four packages takes
12085 102.3@tie{}MiB in total, which is much less than the sum of each closure
12086 since they have a lot of dependencies in common.
12088 When looking at the profile returned by @command{guix size}, you may
12089 find yourself wondering why a given package shows up in the profile at
12090 all. To understand it, you can use @command{guix graph --path -t
12091 references} to display the shortest path between the two packages
12092 (@pxref{Invoking guix graph}).
12094 The available options are:
12098 @item --substitute-urls=@var{urls}
12099 Use substitute information from @var{urls}.
12100 @xref{client-substitute-urls, the same option for @code{guix build}}.
12102 @item --sort=@var{key}
12103 Sort lines according to @var{key}, one of the following options:
12107 the size of each item (the default);
12109 the total size of the item's closure.
12112 @item --map-file=@var{file}
12113 Write a graphical map of disk usage in PNG format to @var{file}.
12115 For the example above, the map looks like this:
12117 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
12118 produced by @command{guix size}}
12120 This option requires that
12121 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
12122 installed and visible in Guile's module search path. When that is not
12123 the case, @command{guix size} fails as it tries to load it.
12125 @item --system=@var{system}
12126 @itemx -s @var{system}
12127 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
12129 @item --load-path=@var{directory}
12130 @itemx -L @var{directory}
12131 Add @var{directory} to the front of the package module search path
12132 (@pxref{Package Modules}).
12134 This allows users to define their own packages and make them visible to
12135 the command-line tools.
12138 @node Invoking guix graph
12139 @section Invoking @command{guix graph}
12142 @cindex @command{guix graph}
12143 @cindex package dependencies
12144 Packages and their dependencies form a @dfn{graph}, specifically a
12145 directed acyclic graph (DAG). It can quickly become difficult to have a
12146 mental model of the package DAG, so the @command{guix graph} command
12147 provides a visual representation of the DAG@. By default,
12148 @command{guix graph} emits a DAG representation in the input format of
12149 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
12150 directly to the @command{dot} command of Graphviz. It can also emit an
12151 HTML page with embedded JavaScript code to display a ``chord diagram''
12152 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
12153 emit Cypher queries to construct a graph in a graph database supporting
12154 the @uref{https://www.opencypher.org/, openCypher} query language. With
12155 @option{--path}, it simply displays the shortest path between two
12156 packages. The general syntax is:
12159 guix graph @var{options} @var{package}@dots{}
12162 For example, the following command generates a PDF file representing the
12163 package DAG for the GNU@tie{}Core Utilities, showing its build-time
12167 guix graph coreutils | dot -Tpdf > dag.pdf
12170 The output looks like this:
12172 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
12174 Nice little graph, no?
12176 You may find it more pleasant to navigate the graph interactively with
12177 @command{xdot} (from the @code{xdot} package):
12180 guix graph coreutils | xdot -
12183 But there is more than one graph! The one above is concise: it is the
12184 graph of package objects, omitting implicit inputs such as GCC, libc,
12185 grep, etc. It is often useful to have such a concise graph, but
12186 sometimes one may want to see more details. @command{guix graph} supports
12187 several types of graphs, allowing you to choose the level of detail:
12191 This is the default type used in the example above. It shows the DAG of
12192 package objects, excluding implicit dependencies. It is concise, but
12193 filters out many details.
12195 @item reverse-package
12196 This shows the @emph{reverse} DAG of packages. For example:
12199 guix graph --type=reverse-package ocaml
12202 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
12203 you are also interested in cases where OCaml is an implicit dependency, see
12204 @code{reverse-bag} below).
12206 Note that for core packages this can yield huge graphs. If all you want
12207 is to know the number of packages that depend on a given package, use
12208 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
12209 @option{--list-dependent}}).
12212 This is the package DAG, @emph{including} implicit inputs.
12214 For instance, the following command:
12217 guix graph --type=bag-emerged coreutils
12220 ...@: yields this bigger graph:
12222 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
12224 At the bottom of the graph, we see all the implicit inputs of
12225 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
12227 Now, note that the dependencies of these implicit inputs---that is, the
12228 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
12229 here, for conciseness.
12232 Similar to @code{bag-emerged}, but this time including all the bootstrap
12235 @item bag-with-origins
12236 Similar to @code{bag}, but also showing origins and their dependencies.
12239 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
12240 it also takes implicit dependencies into account. For example:
12243 guix graph -t reverse-bag dune
12247 ...@: yields the graph of all packages that depend on Dune, directly or
12248 indirectly. Since Dune is an @emph{implicit} dependency of many packages
12249 @i{via} @code{dune-build-system}, this shows a large number of packages,
12250 whereas @code{reverse-package} would show very few if any.
12253 This is the most detailed representation: It shows the DAG of
12254 derivations (@pxref{Derivations}) and plain store items. Compared to
12255 the above representation, many additional nodes are visible, including
12256 build scripts, patches, Guile modules, etc.
12258 For this type of graph, it is also possible to pass a @file{.drv} file
12259 name instead of a package name, as in:
12262 guix graph -t derivation `guix system build -d my-config.scm`
12266 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
12267 For example, the following command shows the graph for the package
12268 module that defines the @code{guile} package:
12271 guix graph -t module guile | xdot -
12275 All the types above correspond to @emph{build-time dependencies}. The
12276 following graph type represents the @emph{run-time dependencies}:
12280 This is the graph of @dfn{references} of a package output, as returned
12281 by @command{guix gc --references} (@pxref{Invoking guix gc}).
12283 If the given package output is not available in the store, @command{guix
12284 graph} attempts to obtain dependency information from substitutes.
12286 Here you can also pass a store file name instead of a package name. For
12287 example, the command below produces the reference graph of your profile
12288 (which can be big!):
12291 guix graph -t references `readlink -f ~/.guix-profile`
12295 This is the graph of the @dfn{referrers} of a store item, as returned by
12296 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
12298 This relies exclusively on local information from your store. For
12299 instance, let us suppose that the current Inkscape is available in 10
12300 profiles on your machine; @command{guix graph -t referrers inkscape}
12301 will show a graph rooted at Inkscape and with those 10 profiles linked
12304 It can help determine what is preventing a store item from being garbage
12309 @cindex shortest path, between packages
12310 Often, the graph of the package you are interested in does not fit on
12311 your screen, and anyway all you want to know is @emph{why} that package
12312 actually depends on some seemingly unrelated package. The
12313 @option{--path} option instructs @command{guix graph} to display the
12314 shortest path between two packages (or derivations, or store items,
12318 $ guix graph --path emacs libunistring
12321 libunistring@@0.9.10
12322 $ guix graph --path -t derivation emacs libunistring
12323 /gnu/store/@dots{}-emacs-26.3.drv
12324 /gnu/store/@dots{}-mailutils-3.9.drv
12325 /gnu/store/@dots{}-libunistring-0.9.10.drv
12326 $ guix graph --path -t references emacs libunistring
12327 /gnu/store/@dots{}-emacs-26.3
12328 /gnu/store/@dots{}-libidn2-2.2.0
12329 /gnu/store/@dots{}-libunistring-0.9.10
12332 The available options are the following:
12335 @item --type=@var{type}
12336 @itemx -t @var{type}
12337 Produce a graph output of @var{type}, where @var{type} must be one of
12338 the values listed above.
12341 List the supported graph types.
12343 @item --backend=@var{backend}
12344 @itemx -b @var{backend}
12345 Produce a graph using the selected @var{backend}.
12347 @item --list-backends
12348 List the supported graph backends.
12350 Currently, the available backends are Graphviz and d3.js.
12353 Display the shortest path between two nodes of the type specified by
12354 @option{--type}. The example below shows the shortest path between
12355 @code{libreoffice} and @code{llvm} according to the references of
12356 @code{libreoffice}:
12359 $ guix graph --path -t references libreoffice llvm
12360 /gnu/store/@dots{}-libreoffice-6.4.2.2
12361 /gnu/store/@dots{}-libepoxy-1.5.4
12362 /gnu/store/@dots{}-mesa-19.3.4
12363 /gnu/store/@dots{}-llvm-9.0.1
12366 @item --expression=@var{expr}
12367 @itemx -e @var{expr}
12368 Consider the package @var{expr} evaluates to.
12370 This is useful to precisely refer to a package, as in this example:
12373 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
12376 @item --system=@var{system}
12377 @itemx -s @var{system}
12378 Display the graph for @var{system}---e.g., @code{i686-linux}.
12380 The package dependency graph is largely architecture-independent, but there
12381 are some architecture-dependent bits that this option allows you to visualize.
12383 @item --load-path=@var{directory}
12384 @itemx -L @var{directory}
12385 Add @var{directory} to the front of the package module search path
12386 (@pxref{Package Modules}).
12388 This allows users to define their own packages and make them visible to
12389 the command-line tools.
12392 On top of that, @command{guix graph} supports all the usual package
12393 transformation options (@pxref{Package Transformation Options}). This
12394 makes it easy to view the effect of a graph-rewriting transformation
12395 such as @option{--with-input}. For example, the command below outputs
12396 the graph of @code{git} once @code{openssl} has been replaced by
12397 @code{libressl} everywhere in the graph:
12400 guix graph git --with-input=openssl=libressl
12403 So many possibilities, so much fun!
12405 @node Invoking guix publish
12406 @section Invoking @command{guix publish}
12408 @cindex @command{guix publish}
12409 The purpose of @command{guix publish} is to enable users to easily share
12410 their store with others, who can then use it as a substitute server
12411 (@pxref{Substitutes}).
12413 When @command{guix publish} runs, it spawns an HTTP server which allows
12414 anyone with network access to obtain substitutes from it. This means
12415 that any machine running Guix can also act as if it were a build farm,
12416 since the HTTP interface is compatible with Cuirass, the software behind
12417 the @code{@value{SUBSTITUTE-SERVER}} build farm.
12419 For security, each substitute is signed, allowing recipients to check
12420 their authenticity and integrity (@pxref{Substitutes}). Because
12421 @command{guix publish} uses the signing key of the system, which is only
12422 readable by the system administrator, it must be started as root; the
12423 @option{--user} option makes it drop root privileges early on.
12425 The signing key pair must be generated before @command{guix publish} is
12426 launched, using @command{guix archive --generate-key} (@pxref{Invoking
12429 When the @option{--advertise} option is passed, the server advertises
12430 its availability on the local network using multicast DNS (mDNS) and DNS
12431 service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
12432 guile-avahi, Using Avahi in Guile Scheme Programs}).
12434 The general syntax is:
12437 guix publish @var{options}@dots{}
12440 Running @command{guix publish} without any additional arguments will
12441 spawn an HTTP server on port 8080:
12447 Once a publishing server has been authorized, the daemon may download
12448 substitutes from it. @xref{Getting Substitutes from Other Servers}.
12450 By default, @command{guix publish} compresses archives on the fly as it
12451 serves them. This ``on-the-fly'' mode is convenient in that it requires
12452 no setup and is immediately available. However, when serving lots of
12453 clients, we recommend using the @option{--cache} option, which enables
12454 caching of the archives before they are sent to clients---see below for
12455 details. The @command{guix weather} command provides a handy way to
12456 check what a server provides (@pxref{Invoking guix weather}).
12458 As a bonus, @command{guix publish} also serves as a content-addressed
12459 mirror for source files referenced in @code{origin} records
12460 (@pxref{origin Reference}). For instance, assuming @command{guix
12461 publish} is running on @code{example.org}, the following URL returns the
12462 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
12463 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
12466 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
12469 Obviously, these URLs only work for files that are in the store; in
12470 other cases, they return 404 (``Not Found'').
12472 @cindex build logs, publication
12473 Build logs are available from @code{/log} URLs like:
12476 http://example.org/log/gwspk@dots{}-guile-2.2.3
12480 When @command{guix-daemon} is configured to save compressed build logs,
12481 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
12482 URLs return the compressed log as-is, with an appropriate
12483 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
12484 running @command{guix-daemon} with @option{--log-compression=gzip} since
12485 Web browsers can automatically decompress it, which is not the case with
12488 The following options are available:
12491 @item --port=@var{port}
12492 @itemx -p @var{port}
12493 Listen for HTTP requests on @var{port}.
12495 @item --listen=@var{host}
12496 Listen on the network interface for @var{host}. The default is to
12497 accept connections from any interface.
12499 @item --user=@var{user}
12500 @itemx -u @var{user}
12501 Change privileges to @var{user} as soon as possible---i.e., once the
12502 server socket is open and the signing key has been read.
12504 @item --compression[=@var{method}[:@var{level}]]
12505 @itemx -C [@var{method}[:@var{level}]]
12506 Compress data using the given @var{method} and @var{level}. @var{method} is
12507 one of @code{lzip}, @code{zstd}, and @code{gzip}; when @var{method} is
12508 omitted, @code{gzip} is used.
12510 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
12511 to different compression levels: 1 is the fastest, and 9 is the best
12512 (CPU-intensive). The default is 3.
12514 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a
12515 small increase in CPU usage; see
12516 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip
12517 Web page}. However, @code{lzip} achieves low decompression throughput
12518 (on the order of 50@tie{}MiB/s on modern hardware), which can be a
12519 bottleneck for someone who downloads over a fast network connection.
12521 The compression ratio of @code{zstd} is between that of @code{lzip} and
12522 that of @code{gzip}; its main advantage is a
12523 @uref{https://facebook.github.io/zstd/,high decompression speed}.
12525 Unless @option{--cache} is used, compression occurs on the fly and
12526 the compressed streams are not
12527 cached. Thus, to reduce load on the machine that runs @command{guix
12528 publish}, it may be a good idea to choose a low compression level, to
12529 run @command{guix publish} behind a caching proxy, or to use
12530 @option{--cache}. Using @option{--cache} has the advantage that it
12531 allows @command{guix publish} to add @code{Content-Length} HTTP header
12534 This option can be repeated, in which case every substitute gets compressed
12535 using all the selected methods, and all of them are advertised. This is
12536 useful when users may not support all the compression methods: they can select
12537 the one they support.
12539 @item --cache=@var{directory}
12540 @itemx -c @var{directory}
12541 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
12542 and only serve archives that are in cache.
12544 When this option is omitted, archives and meta-data are created
12545 on-the-fly. This can reduce the available bandwidth, especially when
12546 compression is enabled, since this may become CPU-bound. Another
12547 drawback of the default mode is that the length of archives is not known
12548 in advance, so @command{guix publish} does not add a
12549 @code{Content-Length} HTTP header to its responses, which in turn
12550 prevents clients from knowing the amount of data being downloaded.
12552 Conversely, when @option{--cache} is used, the first request for a store
12553 item (@i{via} a @code{.narinfo} URL) triggers a
12554 background process to @dfn{bake} the archive---computing its
12555 @code{.narinfo} and compressing the archive, if needed. Once the
12556 archive is cached in @var{directory}, subsequent requests succeed and
12557 are served directly from the cache, which guarantees that clients get
12558 the best possible bandwidth.
12560 That first @code{.narinfo} request nonetheless returns 200, provided the
12561 requested store item is ``small enough'', below the cache bypass
12562 threshold---see @option{--cache-bypass-threshold} below. That way,
12563 clients do not have to wait until the archive is baked. For larger
12564 store items, the first @code{.narinfo} request returns 404, meaning that
12565 clients have to wait until the archive is baked.
12567 The ``baking'' process is performed by worker threads. By default, one
12568 thread per CPU core is created, but this can be customized. See
12569 @option{--workers} below.
12571 When @option{--ttl} is used, cached entries are automatically deleted
12572 when they have expired.
12574 @item --workers=@var{N}
12575 When @option{--cache} is used, request the allocation of @var{N} worker
12576 threads to ``bake'' archives.
12578 @item --ttl=@var{ttl}
12579 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
12580 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
12581 days, @code{1m} means 1 month, and so on.
12583 This allows the user's Guix to keep substitute information in cache for
12584 @var{ttl}. However, note that @code{guix publish} does not itself
12585 guarantee that the store items it provides will indeed remain available
12586 for as long as @var{ttl}.
12588 Additionally, when @option{--cache} is used, cached entries that have
12589 not been accessed for @var{ttl} and that no longer have a corresponding
12590 item in the store, may be deleted.
12592 @item --cache-bypass-threshold=@var{size}
12593 When used in conjunction with @option{--cache}, store items smaller than
12594 @var{size} are immediately available, even when they are not yet in
12595 cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
12596 for megabytes and so on. The default is @code{10M}.
12598 ``Cache bypass'' allows you to reduce the publication delay for clients
12599 at the expense of possibly additional I/O and CPU use on the server
12600 side: depending on the client access patterns, those store items can end
12601 up being baked several times until a copy is available in cache.
12603 Increasing the threshold may be useful for sites that have few users, or
12604 to guarantee that users get substitutes even for store items that are
12607 @item --nar-path=@var{path}
12608 Use @var{path} as the prefix for the URLs of ``nar'' files
12609 (@pxref{Invoking guix archive, normalized archives}).
12611 By default, nars are served at a URL such as
12612 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
12613 change the @code{/nar} part to @var{path}.
12615 @item --public-key=@var{file}
12616 @itemx --private-key=@var{file}
12617 Use the specific @var{file}s as the public/private key pair used to sign
12618 the store items being published.
12620 The files must correspond to the same key pair (the private key is used
12621 for signing and the public key is merely advertised in the signature
12622 metadata). They must contain keys in the canonical s-expression format
12623 as produced by @command{guix archive --generate-key} (@pxref{Invoking
12624 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
12625 @file{/etc/guix/signing-key.sec} are used.
12627 @item --repl[=@var{port}]
12628 @itemx -r [@var{port}]
12629 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
12630 Reference Manual}) on @var{port} (37146 by default). This is used
12631 primarily for debugging a running @command{guix publish} server.
12634 Enabling @command{guix publish} on Guix System is a one-liner: just
12635 instantiate a @code{guix-publish-service-type} service in the @code{services} field
12636 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
12637 @code{guix-publish-service-type}}).
12639 If you are instead running Guix on a ``foreign distro'', follow these
12644 If your host distro uses the systemd init system:
12647 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
12648 /etc/systemd/system/
12649 # systemctl start guix-publish && systemctl enable guix-publish
12653 If your host distro uses the Upstart init system:
12656 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
12657 # start guix-publish
12661 Otherwise, proceed similarly with your distro's init system.
12664 @node Invoking guix challenge
12665 @section Invoking @command{guix challenge}
12667 @cindex reproducible builds
12668 @cindex verifiable builds
12669 @cindex @command{guix challenge}
12671 Do the binaries provided by this server really correspond to the source
12672 code it claims to build? Is a package build process deterministic?
12673 These are the questions the @command{guix challenge} command attempts to
12676 The former is obviously an important question: Before using a substitute
12677 server (@pxref{Substitutes}), one had better @emph{verify} that it
12678 provides the right binaries, and thus @emph{challenge} it. The latter
12679 is what enables the former: If package builds are deterministic, then
12680 independent builds of the package should yield the exact same result,
12681 bit for bit; if a server provides a binary different from the one
12682 obtained locally, it may be either corrupt or malicious.
12684 We know that the hash that shows up in @file{/gnu/store} file names is
12685 the hash of all the inputs of the process that built the file or
12686 directory---compilers, libraries, build scripts,
12687 etc. (@pxref{Introduction}). Assuming deterministic build processes,
12688 one store file name should map to exactly one build output.
12689 @command{guix challenge} checks whether there is, indeed, a single
12690 mapping by comparing the build outputs of several independent builds of
12691 any given store item.
12693 The command output looks like this:
12696 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
12697 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
12698 updating list of substitutes from 'https://guix.example.org'... 100.0%
12699 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
12700 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
12701 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
12702 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
12704 /lib/libcrypto.so.1.1
12707 /gnu/store/@dots{}-git-2.5.0 contents differ:
12708 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
12709 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
12710 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
12712 /libexec/git-core/git-fsck
12714 /gnu/store/@dots{}-pius-2.1.1 contents differ:
12715 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
12716 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
12717 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
12719 /share/man/man1/pius.1.gz
12723 6,406 store items were analyzed:
12724 - 4,749 (74.1%) were identical
12725 - 525 (8.2%) differed
12726 - 1,132 (17.7%) were inconclusive
12730 In this example, @command{guix challenge} first scans the store to
12731 determine the set of locally-built derivations---as opposed to store
12732 items that were downloaded from a substitute server---and then queries
12733 all the substitute servers. It then reports those store items for which
12734 the servers obtained a result different from the local build.
12736 @cindex non-determinism, in package builds
12737 As an example, @code{guix.example.org} always gets a different answer.
12738 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
12739 case of Git. This might indicate that the build process of Git is
12740 non-deterministic, meaning that its output varies as a function of
12741 various things that Guix does not fully control, in spite of building
12742 packages in isolated environments (@pxref{Features}). Most common
12743 sources of non-determinism include the addition of timestamps in build
12744 results, the inclusion of random numbers, and directory listings sorted
12745 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
12748 To find out what is wrong with this Git binary, the easiest approach is
12752 guix challenge git \
12753 --diff=diffoscope \
12754 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
12757 This automatically invokes @command{diffoscope}, which displays detailed
12758 information about files that differ.
12760 Alternatively, we can do something along these lines (@pxref{Invoking guix
12764 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-git-2.5.0 \
12765 | lzip -d | guix archive -x /tmp/git
12766 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
12769 This command shows the difference between the files resulting from the
12770 local build, and the files resulting from the build on
12771 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
12772 diffutils, Comparing and Merging Files}). The @command{diff} command
12773 works great for text files. When binary files differ, a better option
12774 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
12775 visualize differences for all kinds of files.
12777 Once you have done that work, you can tell whether the differences are due
12778 to a non-deterministic build process or to a malicious server. We try
12779 hard to remove sources of non-determinism in packages to make it easier
12780 to verify substitutes, but of course, this is a process that
12781 involves not just Guix, but a large part of the free software community.
12782 In the meantime, @command{guix challenge} is one tool to help address
12785 If you are writing packages for Guix, you are encouraged to check
12786 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
12787 same build result as you did with:
12790 $ guix challenge @var{package}
12794 where @var{package} is a package specification such as
12795 @code{guile@@2.0} or @code{glibc:debug}.
12797 The general syntax is:
12800 guix challenge @var{options} [@var{packages}@dots{}]
12803 When a difference is found between the hash of a locally-built item and
12804 that of a server-provided substitute, or among substitutes provided by
12805 different servers, the command displays it as in the example above and
12806 its exit code is 2 (other non-zero exit codes denote other kinds of
12809 The one option that matters is:
12813 @item --substitute-urls=@var{urls}
12814 Consider @var{urls} the whitespace-separated list of substitute source
12815 URLs to compare to.
12817 @item --diff=@var{mode}
12818 Upon mismatches, show differences according to @var{mode}, one of:
12821 @item @code{simple} (the default)
12822 Show the list of files that differ.
12824 @item @code{diffoscope}
12825 @itemx @var{command}
12826 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
12827 two directories whose contents do not match.
12829 When @var{command} is an absolute file name, run @var{command} instead
12833 Do not show further details about the differences.
12836 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
12837 downloads the store items from the given substitute servers so that it
12842 Show details about matches (identical contents) in addition to
12843 information about mismatches.
12847 @node Invoking guix copy
12848 @section Invoking @command{guix copy}
12850 @cindex copy, of store items, over SSH
12851 @cindex SSH, copy of store items
12852 @cindex sharing store items across machines
12853 @cindex transferring store items across machines
12854 The @command{guix copy} command copies items from the store of one
12855 machine to that of another machine over a secure shell (SSH)
12856 connection@footnote{This command is available only when Guile-SSH was
12857 found. @xref{Requirements}, for details.}. For example, the following
12858 command copies the @code{coreutils} package, the user's profile, and all
12859 their dependencies over to @var{host}, logged in as @var{user}:
12862 guix copy --to=@var{user}@@@var{host} \
12863 coreutils `readlink -f ~/.guix-profile`
12866 If some of the items to be copied are already present on @var{host},
12867 they are not actually sent.
12869 The command below retrieves @code{libreoffice} and @code{gimp} from
12870 @var{host}, assuming they are available there:
12873 guix copy --from=@var{host} libreoffice gimp
12876 The SSH connection is established using the Guile-SSH client, which is
12877 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
12878 @file{~/.ssh/config}, and uses the SSH agent for authentication.
12880 The key used to sign items that are sent must be accepted by the remote
12881 machine. Likewise, the key used by the remote machine to sign items you
12882 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
12883 own daemon. @xref{Invoking guix archive}, for more information about
12884 store item authentication.
12886 The general syntax is:
12889 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
12892 You must always specify one of the following options:
12895 @item --to=@var{spec}
12896 @itemx --from=@var{spec}
12897 Specify the host to send to or receive from. @var{spec} must be an SSH
12898 spec such as @code{example.org}, @code{charlie@@example.org}, or
12899 @code{charlie@@example.org:2222}.
12902 The @var{items} can be either package names, such as @code{gimp}, or
12903 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
12905 When specifying the name of a package to send, it is first built if
12906 needed, unless @option{--dry-run} was specified. Common build options
12907 are supported (@pxref{Common Build Options}).
12910 @node Invoking guix container
12911 @section Invoking @command{guix container}
12913 @cindex @command{guix container}
12915 As of version @value{VERSION}, this tool is experimental. The interface
12916 is subject to radical change in the future.
12919 The purpose of @command{guix container} is to manipulate processes
12920 running within an isolated environment, commonly known as a
12921 ``container'', typically created by the @command{guix environment}
12922 (@pxref{Invoking guix environment}) and @command{guix system container}
12923 (@pxref{Invoking guix system}) commands.
12925 The general syntax is:
12928 guix container @var{action} @var{options}@dots{}
12931 @var{action} specifies the operation to perform with a container, and
12932 @var{options} specifies the context-specific arguments for the action.
12934 The following actions are available:
12938 Execute a command within the context of a running container.
12943 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
12946 @var{pid} specifies the process ID of the running container.
12947 @var{program} specifies an executable file name within the root file
12948 system of the container. @var{arguments} are the additional options that
12949 will be passed to @var{program}.
12951 The following command launches an interactive login shell inside a
12952 Guix system container, started by @command{guix system container}, and whose
12953 process ID is 9001:
12956 guix container exec 9001 /run/current-system/profile/bin/bash --login
12959 Note that the @var{pid} cannot be the parent process of a container. It
12960 must be PID 1 of the container or one of its child processes.
12964 @node Invoking guix weather
12965 @section Invoking @command{guix weather}
12967 Occasionally you're grumpy because substitutes are lacking and you end
12968 up building packages by yourself (@pxref{Substitutes}). The
12969 @command{guix weather} command reports on substitute availability on the
12970 specified servers so you can have an idea of whether you'll be grumpy
12971 today. It can sometimes be useful info as a user, but it is primarily
12972 useful to people running @command{guix publish} (@pxref{Invoking guix
12975 @cindex statistics, for substitutes
12976 @cindex availability of substitutes
12977 @cindex substitute availability
12978 @cindex weather, substitute availability
12979 Here's a sample run:
12982 $ guix weather --substitute-urls=https://guix.example.org
12983 computing 5,872 package derivations for x86_64-linux...
12984 looking for 6,128 store items on https://guix.example.org..
12985 updating list of substitutes from 'https://guix.example.org'... 100.0%
12986 https://guix.example.org
12987 43.4% substitutes available (2,658 out of 6,128)
12988 7,032.5 MiB of nars (compressed)
12989 19,824.2 MiB on disk (uncompressed)
12990 0.030 seconds per request (182.9 seconds in total)
12991 33.5 requests per second
12993 9.8% (342 out of 3,470) of the missing items are queued
12995 x86_64-linux: 518 (59.7%)
12996 i686-linux: 221 (25.5%)
12997 aarch64-linux: 128 (14.8%)
12998 build rate: 23.41 builds per hour
12999 x86_64-linux: 11.16 builds per hour
13000 i686-linux: 6.03 builds per hour
13001 aarch64-linux: 6.41 builds per hour
13004 @cindex continuous integration, statistics
13005 As you can see, it reports the fraction of all the packages for which
13006 substitutes are available on the server---regardless of whether
13007 substitutes are enabled, and regardless of whether this server's signing
13008 key is authorized. It also reports the size of the compressed archives
13009 (``nars'') provided by the server, the size the corresponding store
13010 items occupy in the store (assuming deduplication is turned off), and
13011 the server's throughput. The second part gives continuous integration
13012 (CI) statistics, if the server supports it. In addition, using the
13013 @option{--coverage} option, @command{guix weather} can list ``important''
13014 package substitutes missing on the server (see below).
13016 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
13017 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
13018 challenge}, it ignores signatures on those substitutes, which is
13019 innocuous since the command only gathers statistics and cannot install
13022 The general syntax is:
13025 guix weather @var{options}@dots{} [@var{packages}@dots{}]
13028 When @var{packages} is omitted, @command{guix weather} checks the availability
13029 of substitutes for @emph{all} the packages, or for those specified with
13030 @option{--manifest}; otherwise it only considers the specified packages. It
13031 is also possible to query specific system types with @option{--system}.
13032 @command{guix weather} exits with a non-zero code when the fraction of
13033 available substitutes is below 100%.
13035 The available options are listed below.
13038 @item --substitute-urls=@var{urls}
13039 @var{urls} is the space-separated list of substitute server URLs to
13040 query. When this option is omitted, the default set of substitute
13041 servers is queried.
13043 @item --system=@var{system}
13044 @itemx -s @var{system}
13045 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
13046 option can be repeated, in which case @command{guix weather} will query
13047 substitutes for several system types.
13049 @item --manifest=@var{file}
13050 Instead of querying substitutes for all the packages, only ask for those
13051 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
13052 with the @code{-m} option of @command{guix package} (@pxref{Invoking
13055 This option can be repeated several times, in which case the manifests
13058 @item --coverage[=@var{count}]
13059 @itemx -c [@var{count}]
13060 Report on substitute coverage for packages: list packages with at least
13061 @var{count} dependents (zero by default) for which substitutes are
13062 unavailable. Dependent packages themselves are not listed: if @var{b} depends
13063 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
13064 @var{b} usually lacks substitutes as well. The result looks like this:
13067 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
13068 computing 8,983 package derivations for x86_64-linux...
13069 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
13070 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
13071 @value{SUBSTITUTE-URL}
13072 64.7% substitutes available (6,047 out of 9,343)
13074 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
13075 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
13076 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
13077 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
13081 What this example shows is that @code{kcoreaddons} and presumably the 58
13082 packages that depend on it have no substitutes at
13083 @code{@value{SUBSTITUTE-SERVER}}; likewise for @code{qgpgme} and the 46
13084 packages that depend on it.
13086 If you are a Guix developer, or if you are taking care of this build farm,
13087 you'll probably want to have a closer look at these packages: they may simply
13090 @item --display-missing
13091 Display the list of store items for which substitutes are missing.
13094 @node Invoking guix processes
13095 @section Invoking @command{guix processes}
13097 The @command{guix processes} command can be useful to developers and system
13098 administrators, especially on multi-user machines and on build farms: it lists
13099 the current sessions (connections to the daemon), as well as information about
13100 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
13101 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
13102 listed.}. Here's an example of the information it returns:
13105 $ sudo guix processes
13108 ClientCommand: guix environment --ad-hoc python
13112 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
13116 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
13117 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
13118 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
13119 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
13121 ChildCommand: guix offload x86_64-linux 7200 1 28800
13123 ChildCommand: guix offload x86_64-linux 7200 1 28800
13125 ChildCommand: guix offload x86_64-linux 7200 1 28800
13128 In this example we see that @command{guix-daemon} has three clients:
13129 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
13130 integration tool; their process identifier (PID) is given by the
13131 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
13132 @command{guix-daemon} sub-process of this particular session.
13134 The @code{LockHeld} fields show which store items are currently locked
13135 by this session, which corresponds to store items being built or
13136 substituted (the @code{LockHeld} field is not displayed when
13137 @command{guix processes} is not running as root). Last, by looking at
13138 the @code{ChildPID} and @code{ChildCommand} fields, we understand that
13139 these three builds are being offloaded (@pxref{Daemon Offload Setup}).
13141 The output is in Recutils format so we can use the handy @command{recsel}
13142 command to select sessions of interest (@pxref{Selection Expressions,,,
13143 recutils, GNU recutils manual}). As an example, the command shows the command
13144 line and PID of the client that triggered the build of a Perl package:
13147 $ sudo guix processes | \
13148 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
13150 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
13153 Additional options are listed below.
13156 @item --format=@var{format}
13157 @itemx -f @var{format}
13158 Produce output in the specified @var{format}, one of:
13162 The default option. It outputs a set of Session recutils records
13163 that include each @code{ChildProcess} as a field.
13166 Normalize the output records into record sets (@pxref{Record Sets,,,
13167 recutils, GNU recutils manual}). Normalizing into record sets allows
13168 joins across record types. The example below lists the PID of each
13169 @code{ChildProcess} and the associated PID for @code{Session} that
13170 spawned the @code{ChildProcess} where the @code{Session} was started
13171 using @command{guix build}.
13174 $ guix processes --format=normalized | \
13178 -p Session.PID,PID \
13179 -e 'Session.ClientCommand ~ "guix build"'
13192 @node System Configuration
13193 @chapter System Configuration
13195 @cindex system configuration
13196 Guix System supports a consistent whole-system configuration
13197 mechanism. By that we mean that all aspects of the global system
13198 configuration---such as the available system services, timezone and
13199 locale settings, user accounts---are declared in a single place. Such
13200 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
13202 One of the advantages of putting all the system configuration under the
13203 control of Guix is that it supports transactional system upgrades, and
13204 makes it possible to roll back to a previous system instantiation,
13205 should something go wrong with the new one (@pxref{Features}). Another
13206 advantage is that it makes it easy to replicate the exact same configuration
13207 across different machines, or at different points in time, without
13208 having to resort to additional administration tools layered on top of
13209 the own tools of the system.
13210 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
13212 This section describes this mechanism. First we focus on the system
13213 administrator's viewpoint---explaining how the system is configured and
13214 instantiated. Then we show how this mechanism can be extended, for
13215 instance to support new system services.
13218 * Using the Configuration System:: Customizing your GNU system.
13219 * operating-system Reference:: Detail of operating-system declarations.
13220 * File Systems:: Configuring file system mounts.
13221 * Mapped Devices:: Block device extra processing.
13222 * User Accounts:: Specifying user accounts.
13223 * Keyboard Layout:: How the system interprets key strokes.
13224 * Locales:: Language and cultural convention settings.
13225 * Services:: Specifying system services.
13226 * Setuid Programs:: Programs running with root privileges.
13227 * X.509 Certificates:: Authenticating HTTPS servers.
13228 * Name Service Switch:: Configuring libc's name service switch.
13229 * Initial RAM Disk:: Linux-Libre bootstrapping.
13230 * Bootloader Configuration:: Configuring the boot loader.
13231 * Invoking guix system:: Instantiating a system configuration.
13232 * Invoking guix deploy:: Deploying a system configuration to a remote host.
13233 * Running Guix in a VM:: How to run Guix System in a virtual machine.
13234 * Defining Services:: Adding new service definitions.
13237 @node Using the Configuration System
13238 @section Using the Configuration System
13240 The operating system is configured by providing an
13241 @code{operating-system} declaration in a file that can then be passed to
13242 the @command{guix system} command (@pxref{Invoking guix system}). A
13243 simple setup, with the default system services, the default Linux-Libre
13244 kernel, initial RAM disk, and boot loader looks like this:
13246 @findex operating-system
13248 @include os-config-bare-bones.texi
13251 This example should be self-describing. Some of the fields defined
13252 above, such as @code{host-name} and @code{bootloader}, are mandatory.
13253 Others, such as @code{packages} and @code{services}, can be omitted, in
13254 which case they get a default value.
13256 Below we discuss the effect of some of the most important fields
13257 (@pxref{operating-system Reference}, for details about all the available
13258 fields), and how to @dfn{instantiate} the operating system using
13259 @command{guix system}.
13261 @unnumberedsubsec Bootloader
13263 @cindex legacy boot, on Intel machines
13264 @cindex BIOS boot, on Intel machines
13267 The @code{bootloader} field describes the method that will be used to boot
13268 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
13269 mode, as in the example above. However, more recent machines rely instead on
13270 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
13271 the @code{bootloader} field should contain something along these lines:
13274 (bootloader-configuration
13275 (bootloader grub-efi-bootloader)
13276 (target "/boot/efi"))
13279 @xref{Bootloader Configuration}, for more information on the available
13280 configuration options.
13282 @unnumberedsubsec Globally-Visible Packages
13284 @vindex %base-packages
13285 The @code{packages} field lists packages that will be globally visible
13286 on the system, for all user accounts---i.e., in every user's @env{PATH}
13287 environment variable---in addition to the per-user profiles
13288 (@pxref{Invoking guix package}). The @code{%base-packages} variable
13289 provides all the tools one would expect for basic user and administrator
13290 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
13291 the GNU Zile lightweight text editor, @command{find}, @command{grep},
13292 etc. The example above adds GNU@tie{}Screen to those,
13293 taken from the @code{(gnu packages screen)}
13294 module (@pxref{Package Modules}). The
13295 @code{(list package output)} syntax can be used to add a specific output
13299 (use-modules (gnu packages))
13300 (use-modules (gnu packages dns))
13304 (packages (cons (list bind "utils")
13308 @findex specification->package
13309 Referring to packages by variable name, like @code{bind} above, has
13310 the advantage of being unambiguous; it also allows typos and such to be
13311 diagnosed right away as ``unbound variables''. The downside is that one
13312 needs to know which module defines which package, and to augment the
13313 @code{use-package-modules} line accordingly. To avoid that, one can use
13314 the @code{specification->package} procedure of the @code{(gnu packages)}
13315 module, which returns the best package for a given name or name and
13319 (use-modules (gnu packages))
13323 (packages (append (map specification->package
13324 '("tcpdump" "htop" "gnupg@@2.0"))
13328 @unnumberedsubsec System Services
13331 @vindex %base-services
13332 The @code{services} field lists @dfn{system services} to be made
13333 available when the system starts (@pxref{Services}).
13334 The @code{operating-system} declaration above specifies that, in
13335 addition to the basic services, we want the OpenSSH secure shell
13336 daemon listening on port 2222 (@pxref{Networking Services,
13337 @code{openssh-service-type}}). Under the hood,
13338 @code{openssh-service-type} arranges so that @command{sshd} is started with the
13339 right command-line options, possibly with supporting configuration files
13340 generated as needed (@pxref{Defining Services}).
13342 @cindex customization, of services
13343 @findex modify-services
13344 Occasionally, instead of using the base services as is, you will want to
13345 customize them. To do this, use @code{modify-services} (@pxref{Service
13346 Reference, @code{modify-services}}) to modify the list.
13348 For example, suppose you want to modify @code{guix-daemon} and Mingetty
13349 (the console log-in) in the @code{%base-services} list (@pxref{Base
13350 Services, @code{%base-services}}). To do that, you can write the
13351 following in your operating system declaration:
13354 (define %my-services
13355 ;; My very own list of services.
13356 (modify-services %base-services
13357 (guix-service-type config =>
13358 (guix-configuration
13360 ;; Fetch substitutes from example.org.
13362 (list "https://example.org/guix"
13363 "https://ci.guix.gnu.org"))))
13364 (mingetty-service-type config =>
13365 (mingetty-configuration
13367 ;; Automatially log in as "guest".
13368 (auto-login "guest")))))
13372 (services %my-services))
13375 This changes the configuration---i.e., the service parameters---of the
13376 @code{guix-service-type} instance, and that of all the
13377 @code{mingetty-service-type} instances in the @code{%base-services} list.
13378 Observe how this is accomplished: first, we arrange for the original
13379 configuration to be bound to the identifier @code{config} in the
13380 @var{body}, and then we write the @var{body} so that it evaluates to the
13381 desired configuration. In particular, notice how we use @code{inherit}
13382 to create a new configuration which has the same values as the old
13383 configuration, but with a few modifications.
13385 @cindex encrypted disk
13386 The configuration for a typical ``desktop'' usage, with an encrypted
13387 root partition, the X11 display
13388 server, GNOME and Xfce (users can choose which of these desktop
13389 environments to use at the log-in screen by pressing @kbd{F1}), network
13390 management, power management, and more, would look like this:
13393 @include os-config-desktop.texi
13396 A graphical system with a choice of lightweight window managers
13397 instead of full-blown desktop environments would look like this:
13400 @include os-config-lightweight-desktop.texi
13403 This example refers to the @file{/boot/efi} file system by its UUID,
13404 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
13405 as returned by the @command{blkid} command.
13407 @xref{Desktop Services}, for the exact list of services provided by
13408 @code{%desktop-services}. @xref{X.509 Certificates}, for background
13409 information about the @code{nss-certs} package that is used here.
13411 Again, @code{%desktop-services} is just a list of service objects. If
13412 you want to remove services from there, you can do so using the
13413 procedures for list filtering (@pxref{SRFI-1 Filtering and
13414 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
13415 following expression returns a list that contains all the services in
13416 @code{%desktop-services} minus the Avahi service:
13419 (remove (lambda (service)
13420 (eq? (service-kind service) avahi-service-type))
13424 @unnumberedsubsec Instantiating the System
13426 Assuming the @code{operating-system} declaration
13427 is stored in the @file{my-system-config.scm}
13428 file, the @command{guix system reconfigure my-system-config.scm} command
13429 instantiates that configuration, and makes it the default GRUB boot
13430 entry (@pxref{Invoking guix system}).
13432 The normal way to change the system configuration is by updating this
13433 file and re-running @command{guix system reconfigure}. One should never
13434 have to touch files in @file{/etc} or to run commands that modify the
13435 system state such as @command{useradd} or @command{grub-install}. In
13436 fact, you must avoid that since that would not only void your warranty
13437 but also prevent you from rolling back to previous versions of your
13438 system, should you ever need to.
13440 @cindex roll-back, of the operating system
13441 Speaking of roll-back, each time you run @command{guix system
13442 reconfigure}, a new @dfn{generation} of the system is created---without
13443 modifying or deleting previous generations. Old system generations get
13444 an entry in the bootloader boot menu, allowing you to boot them in case
13445 something went wrong with the latest generation. Reassuring, no? The
13446 @command{guix system list-generations} command lists the system
13447 generations available on disk. It is also possible to roll back the
13448 system via the commands @command{guix system roll-back} and
13449 @command{guix system switch-generation}.
13451 Although the @command{guix system reconfigure} command will not modify
13452 previous generations, you must take care when the current generation is not
13453 the latest (e.g., after invoking @command{guix system roll-back}), since
13454 the operation might overwrite a later generation (@pxref{Invoking guix
13457 @unnumberedsubsec The Programming Interface
13459 At the Scheme level, the bulk of an @code{operating-system} declaration
13460 is instantiated with the following monadic procedure (@pxref{The Store
13463 @deffn {Monadic Procedure} operating-system-derivation os
13464 Return a derivation that builds @var{os}, an @code{operating-system}
13465 object (@pxref{Derivations}).
13467 The output of the derivation is a single directory that refers to all
13468 the packages, configuration files, and other supporting files needed to
13469 instantiate @var{os}.
13472 This procedure is provided by the @code{(gnu system)} module. Along
13473 with @code{(gnu services)} (@pxref{Services}), this module contains the
13474 guts of Guix System. Make sure to visit it!
13477 @node operating-system Reference
13478 @section @code{operating-system} Reference
13480 This section summarizes all the options available in
13481 @code{operating-system} declarations (@pxref{Using the Configuration
13484 @deftp {Data Type} operating-system
13485 This is the data type representing an operating system configuration.
13486 By that, we mean all the global system configuration, not per-user
13487 configuration (@pxref{Using the Configuration System}).
13490 @item @code{kernel} (default: @code{linux-libre})
13491 The package object of the operating system kernel to
13492 use@footnote{Currently only the Linux-libre kernel is fully supported.
13493 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
13494 available when building a virtual machine disk image.}.
13497 @item @code{hurd} (default: @code{#f})
13498 The package object of the Hurd to be started by the kernel. When this
13499 field is set, produce a GNU/Hurd operating system. In that case,
13500 @code{kernel} must also be set to the @code{gnumach} package---the
13501 microkernel the Hurd runs on.
13504 This feature is experimental and only supported for disk images.
13507 @item @code{kernel-loadable-modules} (default: '())
13508 A list of objects (usually packages) to collect loadable kernel modules
13509 from--e.g. @code{(list ddcci-driver-linux)}.
13511 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
13512 List of strings or gexps representing additional arguments to pass on
13513 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
13515 @item @code{bootloader}
13516 The system bootloader configuration object. @xref{Bootloader Configuration}.
13519 This is the label (a string) as it appears in the bootloader's menu entry.
13520 The default label includes the kernel name and version.
13522 @item @code{keyboard-layout} (default: @code{#f})
13523 This field specifies the keyboard layout to use in the console. It can be
13524 either @code{#f}, in which case the default keyboard layout is used (usually
13525 US English), or a @code{<keyboard-layout>} record. @xref{Keyboard Layout},
13526 for more information.
13528 This keyboard layout is in effect as soon as the kernel has booted. For
13529 instance, it is the keyboard layout in effect when you type a passphrase if
13530 your root file system is on a @code{luks-device-mapping} mapped device
13531 (@pxref{Mapped Devices}).
13534 This does @emph{not} specify the keyboard layout used by the bootloader, nor
13535 that used by the graphical display server. @xref{Bootloader Configuration},
13536 for information on how to specify the bootloader's keyboard layout. @xref{X
13537 Window}, for information on how to specify the keyboard layout used by the X
13541 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
13543 @cindex initial RAM disk
13544 The list of Linux kernel modules that need to be available in the
13545 initial RAM disk. @xref{Initial RAM Disk}.
13547 @item @code{initrd} (default: @code{base-initrd})
13548 A procedure that returns an initial RAM disk for the Linux
13549 kernel. This field is provided to support low-level customization and
13550 should rarely be needed for casual use. @xref{Initial RAM Disk}.
13552 @item @code{firmware} (default: @code{%base-firmware})
13554 List of firmware packages loadable by the operating system kernel.
13556 The default includes firmware needed for Atheros- and Broadcom-based
13557 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
13558 respectively). @xref{Hardware Considerations}, for more info on
13559 supported hardware.
13561 @item @code{host-name}
13564 @item @code{hosts-file}
13566 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
13567 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
13568 Reference Manual}). The default is a file with entries for
13569 @code{localhost} and @var{host-name}.
13571 @item @code{mapped-devices} (default: @code{'()})
13572 A list of mapped devices. @xref{Mapped Devices}.
13574 @item @code{file-systems}
13575 A list of file systems. @xref{File Systems}.
13577 @cindex swap devices
13579 @item @code{swap-devices} (default: @code{'()})
13580 A list of UUIDs, file system labels, or strings identifying devices or
13581 files to be used for ``swap
13582 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
13583 Manual}). Here are some examples:
13586 @item (list (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb"))
13587 Use the swap partition with the given UUID@. You can learn the UUID of a
13588 Linux swap partition by running @command{swaplabel @var{device}}, where
13589 @var{device} is the @file{/dev} file name of that partition.
13591 @item (list (file-system-label "swap"))
13592 Use the partition with label @code{swap}. Again, the
13593 @command{swaplabel} command allows you to view and change the label of a
13594 Linux swap partition.
13596 @item (list "/swapfile")
13597 Use the file @file{/swapfile} as swap space.
13599 @item (list "/dev/sda3" "/dev/sdb2")
13600 Use the @file{/dev/sda3} and @file{/dev/sdb2} partitions as swap space.
13601 We recommend referring to swap devices by UUIDs or labels as shown above
13605 It is possible to specify a swap file in a file system on a mapped
13606 device (under @file{/dev/mapper}), provided that the necessary device
13607 mapping and file system are also specified. @xref{Mapped Devices} and
13608 @ref{File Systems}.
13610 @item @code{users} (default: @code{%base-user-accounts})
13611 @itemx @code{groups} (default: @code{%base-groups})
13612 List of user accounts and groups. @xref{User Accounts}.
13614 If the @code{users} list lacks a user account with UID@tie{}0, a
13615 ``root'' account with UID@tie{}0 is automatically added.
13617 @item @code{skeletons} (default: @code{(default-skeletons)})
13618 A list of target file name/file-like object tuples (@pxref{G-Expressions,
13619 file-like objects}). These are the skeleton files that will be added to
13620 the home directory of newly-created user accounts.
13622 For instance, a valid value may look like this:
13625 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
13626 (".guile" ,(plain-file "guile"
13627 "(use-modules (ice-9 readline))
13628 (activate-readline)")))
13631 @item @code{issue} (default: @code{%default-issue})
13632 A string denoting the contents of the @file{/etc/issue} file, which is
13633 displayed when users log in on a text console.
13635 @item @code{packages} (default: @code{%base-packages})
13636 A list of packages to be installed in the global profile, which is accessible
13637 at @file{/run/current-system/profile}. Each element is either a package
13638 variable or a package/output tuple. Here's a simple example of both:
13641 (cons* git ; the default "out" output
13642 (list git "send-email") ; another output of git
13643 %base-packages) ; the default set
13646 The default set includes core utilities and it is good practice to
13647 install non-core utilities in user profiles (@pxref{Invoking guix
13650 @item @code{timezone}
13651 A timezone identifying string---e.g., @code{"Europe/Paris"}.
13653 You can run the @command{tzselect} command to find out which timezone
13654 string corresponds to your region. Choosing an invalid timezone name
13655 causes @command{guix system} to fail.
13657 @item @code{locale} (default: @code{"en_US.utf8"})
13658 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
13659 Library Reference Manual}). @xref{Locales}, for more information.
13661 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
13662 The list of locale definitions to be compiled and that may be used at
13663 run time. @xref{Locales}.
13665 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
13666 The list of GNU@tie{}libc packages whose locale data and tools are used
13667 to build the locale definitions. @xref{Locales}, for compatibility
13668 considerations that justify this option.
13670 @item @code{name-service-switch} (default: @code{%default-nss})
13671 Configuration of the libc name service switch (NSS)---a
13672 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
13675 @item @code{services} (default: @code{%base-services})
13676 A list of service objects denoting system services. @xref{Services}.
13678 @cindex essential services
13679 @item @code{essential-services} (default: ...)
13680 The list of ``essential services''---i.e., things like instances of
13681 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
13682 Reference}), which are derived from the operating system definition itself.
13683 As a user you should @emph{never} need to touch this field.
13685 @item @code{pam-services} (default: @code{(base-pam-services)})
13687 @cindex pluggable authentication modules
13688 Linux @dfn{pluggable authentication module} (PAM) services.
13689 @c FIXME: Add xref to PAM services section.
13691 @item @code{setuid-programs} (default: @code{%setuid-programs})
13692 List of string-valued G-expressions denoting setuid programs.
13693 @xref{Setuid Programs}.
13695 @item @code{sudoers-file} (default: @code{%sudoers-specification})
13696 @cindex sudoers file
13697 The contents of the @file{/etc/sudoers} file as a file-like object
13698 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
13700 This file specifies which users can use the @command{sudo} command, what
13701 they are allowed to do, and what privileges they may gain. The default
13702 is that only @code{root} and members of the @code{wheel} group may use
13707 @deffn {Scheme Syntax} this-operating-system
13708 When used in the @emph{lexical scope} of an operating system field definition,
13709 this identifier resolves to the operating system being defined.
13711 The example below shows how to refer to the operating system being defined in
13712 the definition of the @code{label} field:
13715 (use-modules (gnu) (guix))
13719 (label (package-full-name
13720 (operating-system-kernel this-operating-system))))
13723 It is an error to refer to @code{this-operating-system} outside an operating
13730 @section File Systems
13732 The list of file systems to be mounted is specified in the
13733 @code{file-systems} field of the operating system declaration
13734 (@pxref{Using the Configuration System}). Each file system is declared
13735 using the @code{file-system} form, like this:
13739 (mount-point "/home")
13740 (device "/dev/sda3")
13744 As usual, some of the fields are mandatory---those shown in the example
13745 above---while others can be omitted. These are described below.
13747 @deftp {Data Type} file-system
13748 Objects of this type represent file systems to be mounted. They
13749 contain the following members:
13753 This is a string specifying the type of the file system---e.g.,
13756 @item @code{mount-point}
13757 This designates the place where the file system is to be mounted.
13759 @item @code{device}
13760 This names the ``source'' of the file system. It can be one of three
13761 things: a file system label, a file system UUID, or the name of a
13762 @file{/dev} node. Labels and UUIDs offer a way to refer to file
13763 systems without having to hard-code their actual device
13764 name@footnote{Note that, while it is tempting to use
13765 @file{/dev/disk/by-uuid} and similar device names to achieve the same
13766 result, this is not recommended: These special device nodes are created
13767 by the udev daemon and may be unavailable at the time the device is
13770 @findex file-system-label
13771 File system labels are created using the @code{file-system-label}
13772 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
13773 plain strings. Here's an example of a file system referred to by its
13774 label, as shown by the @command{e2label} command:
13778 (mount-point "/home")
13780 (device (file-system-label "my-home")))
13784 UUIDs are converted from their string representation (as shown by the
13785 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
13786 @code{uuid} form expects 16-byte UUIDs as defined in
13787 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
13788 form of UUID used by the ext2 family of file systems and others, but it
13789 is different from ``UUIDs'' found in FAT file systems, for instance.},
13794 (mount-point "/home")
13796 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
13799 When the source of a file system is a mapped device (@pxref{Mapped
13800 Devices}), its @code{device} field @emph{must} refer to the mapped
13801 device name---e.g., @file{"/dev/mapper/root-partition"}.
13802 This is required so that
13803 the system knows that mounting the file system depends on having the
13804 corresponding device mapping established.
13806 @item @code{flags} (default: @code{'()})
13807 This is a list of symbols denoting mount flags. Recognized flags
13808 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
13809 access to special files), @code{no-suid} (ignore setuid and setgid
13810 bits), @code{no-atime} (do not update file access times),
13811 @code{strict-atime} (update file access time), @code{lazy-time} (only
13812 update time on the in-memory version of the file inode), and
13813 @code{no-exec} (disallow program execution).
13814 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
13815 Manual}, for more information on these flags.
13817 @item @code{options} (default: @code{#f})
13818 This is either @code{#f}, or a string denoting mount options passed to
13819 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
13820 Library Reference Manual}, for details and run @command{man 8 mount} for
13821 options for various file systems. Note that the
13822 @code{file-system-options->alist} and @code{alist->file-system-options}
13823 procedures from @code{(gnu system file-systems)} can be used to convert
13824 file system options given as an association list to the string
13825 representation, and vice-versa.
13827 @item @code{mount?} (default: @code{#t})
13828 This value indicates whether to automatically mount the file system when
13829 the system is brought up. When set to @code{#f}, the file system gets
13830 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
13831 is not automatically mounted.
13833 @item @code{needed-for-boot?} (default: @code{#f})
13834 This Boolean value indicates whether the file system is needed when
13835 booting. If that is true, then the file system is mounted when the
13836 initial RAM disk (initrd) is loaded. This is always the case, for
13837 instance, for the root file system.
13839 @item @code{check?} (default: @code{#t})
13840 This Boolean indicates whether the file system needs to be checked for
13841 errors before being mounted.
13843 @item @code{create-mount-point?} (default: @code{#f})
13844 When true, the mount point is created if it does not exist yet.
13846 @item @code{mount-may-fail?} (default: @code{#f})
13847 When true, this indicates that mounting this file system can fail but
13848 that should not be considered an error. This is useful in unusual
13849 cases; an example of this is @code{efivarfs}, a file system that can
13850 only be mounted on EFI/UEFI systems.
13852 @item @code{dependencies} (default: @code{'()})
13853 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
13854 representing file systems that must be mounted or mapped devices that
13855 must be opened before (and unmounted or closed after) this one.
13857 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
13858 a dependency of @file{/sys/fs/cgroup/cpu} and
13859 @file{/sys/fs/cgroup/memory}.
13861 Another example is a file system that depends on a mapped device, for
13862 example for an encrypted partition (@pxref{Mapped Devices}).
13866 @deffn {Scheme Procedure} file-system-label @var{str}
13867 This procedure returns an opaque file system label from @var{str}, a
13871 (file-system-label "home")
13872 @result{} #<file-system-label "home">
13875 File system labels are used to refer to file systems by label rather
13876 than by device name. See above for examples.
13879 The @code{(gnu system file-systems)} exports the following useful
13882 @defvr {Scheme Variable} %base-file-systems
13883 These are essential file systems that are required on normal systems,
13884 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
13885 below). Operating system declarations should always contain at least
13889 @defvr {Scheme Variable} %pseudo-terminal-file-system
13890 This is the file system to be mounted as @file{/dev/pts}. It supports
13891 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
13892 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
13893 Manual}). Pseudo-terminals are used by terminal emulators such as
13897 @defvr {Scheme Variable} %shared-memory-file-system
13898 This file system is mounted as @file{/dev/shm} and is used to support
13899 memory sharing across processes (@pxref{Memory-mapped I/O,
13900 @code{shm_open},, libc, The GNU C Library Reference Manual}).
13903 @defvr {Scheme Variable} %immutable-store
13904 This file system performs a read-only ``bind mount'' of
13905 @file{/gnu/store}, making it read-only for all the users including
13906 @code{root}. This prevents against accidental modification by software
13907 running as @code{root} or by system administrators.
13909 The daemon itself is still able to write to the store: it remounts it
13910 read-write in its own ``name space.''
13913 @defvr {Scheme Variable} %binary-format-file-system
13914 The @code{binfmt_misc} file system, which allows handling of arbitrary
13915 executable file types to be delegated to user space. This requires the
13916 @code{binfmt.ko} kernel module to be loaded.
13919 @defvr {Scheme Variable} %fuse-control-file-system
13920 The @code{fusectl} file system, which allows unprivileged users to mount
13921 and unmount user-space FUSE file systems. This requires the
13922 @code{fuse.ko} kernel module to be loaded.
13925 The @code{(gnu system uuid)} module provides tools to deal with file
13926 system ``unique identifiers'' (UUIDs).
13928 @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
13929 Return an opaque UUID (unique identifier) object of the given @var{type}
13930 (a symbol) by parsing @var{str} (a string):
13933 (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
13934 @result{} #<<uuid> type: dce bv: @dots{}>
13936 (uuid "1234-ABCD" 'fat)
13937 @result{} #<<uuid> type: fat bv: @dots{}>
13940 @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
13941 @code{ntfs}, or one of the commonly found synonyms for these.
13943 UUIDs are another way to unambiguously refer to file systems in
13944 operating system configuration. See the examples above.
13948 @node Btrfs file system
13949 @subsection Btrfs file system
13951 The Btrfs has special features, such as subvolumes, that merit being
13952 explained in more details. The following section attempts to cover
13953 basic as well as complex uses of a Btrfs file system with the Guix
13956 In its simplest usage, a Btrfs file system can be described, for
13961 (mount-point "/home")
13963 (device (file-system-label "my-home")))
13966 The example below is more complex, as it makes use of a Btrfs
13967 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
13968 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
13969 dependency on @code{mapped-devices}):
13973 (device (file-system-label "my-btrfs-pool"))
13976 (options "subvol=rootfs")
13977 (dependencies mapped-devices))
13980 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
13981 top level during the early boot, and rely on their configuration to
13982 refer to the correct subvolume path within that top level. The
13983 bootloaders operating in this way typically produce their configuration
13984 on a running system where the Btrfs partitions are already mounted and
13985 where the subvolume information is readily available. As an example,
13986 @command{grub-mkconfig}, the configuration generator command shipped
13987 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
13988 path of a subvolume.
13990 The Guix System produces a bootloader configuration using the operating
13991 system configuration as its sole input; it is therefore necessary to
13992 extract the subvolume name on which @file{/gnu/store} lives (if any)
13993 from that operating system configuration. To better illustrate,
13994 consider a subvolume named 'rootfs' which contains the root file system
13995 data. In such situation, the GRUB bootloader would only see the top
13996 level of the root Btrfs partition, e.g.:
14000 ├── rootfs (subvolume directory)
14001 ├── gnu (normal directory)
14002 ├── store (normal directory)
14006 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
14007 of the kernel, initrd binaries and any other files referred to in the
14008 GRUB configuration that must be found during the early boot.
14010 The next example shows a nested hierarchy of subvolumes and
14015 ├── rootfs (subvolume)
14016 ├── gnu (normal directory)
14017 ├── store (subvolume)
14021 This scenario would work without mounting the 'store' subvolume.
14022 Mounting 'rootfs' is sufficient, since the subvolume name matches its
14023 intended mount point in the file system hierarchy. Alternatively, the
14024 'store' subvolume could be referred to by setting the @code{subvol}
14025 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
14027 Finally, a more contrived example of nested subvolumes:
14031 ├── root-snapshots (subvolume)
14032 ├── root-current (subvolume)
14033 ├── guix-store (subvolume)
14037 Here, the 'guix-store' subvolume doesn't match its intended mount point,
14038 so it is necessary to mount it. The subvolume must be fully specified,
14039 by passing its file name to the @code{subvol} option. To illustrate,
14040 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
14041 a file system declaration such as:
14045 (device (file-system-label "btrfs-pool-1"))
14046 (mount-point "/gnu/store")
14048 (options "subvol=root-snapshots/root-current/guix-store,\
14049 compress-force=zstd,space_cache=v2"))
14052 @node Mapped Devices
14053 @section Mapped Devices
14055 @cindex device mapping
14056 @cindex mapped devices
14057 The Linux kernel has a notion of @dfn{device mapping}: a block device,
14058 such as a hard disk partition, can be @dfn{mapped} into another device,
14059 usually in @code{/dev/mapper/},
14060 with additional processing over the data that flows through
14061 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
14062 concept of a ``mapped device'' and that of a file system: both boil down
14063 to @emph{translating} input/output operations made on a file to
14064 operations on its backing store. Thus, the Hurd implements mapped
14065 devices, like file systems, using the generic @dfn{translator} mechanism
14066 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
14067 typical example is encryption device mapping: all writes to the mapped
14068 device are encrypted, and all reads are deciphered, transparently.
14069 Guix extends this notion by considering any device or set of devices that
14070 are @dfn{transformed} in some way to create a new device; for instance,
14071 RAID devices are obtained by @dfn{assembling} several other devices, such
14072 as hard disks or partitions, into a new one that behaves as one partition.
14074 Mapped devices are declared using the @code{mapped-device} form,
14075 defined as follows; for examples, see below.
14077 @deftp {Data Type} mapped-device
14078 Objects of this type represent device mappings that will be made when
14079 the system boots up.
14083 This is either a string specifying the name of the block device to be mapped,
14084 such as @code{"/dev/sda3"}, or a list of such strings when several devices
14085 need to be assembled for creating a new one. In case of LVM this is a
14086 string specifying name of the volume group to be mapped.
14089 This string specifies the name of the resulting mapped device. For
14090 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
14091 specifying @code{"my-partition"} leads to the creation of
14092 the @code{"/dev/mapper/my-partition"} device.
14093 For RAID devices of type @code{raid-device-mapping}, the full device name
14094 such as @code{"/dev/md0"} needs to be given.
14095 LVM logical volumes of type @code{lvm-device-mapping} need to
14096 be specified as @code{"VGNAME-LVNAME"}.
14099 This list of strings specifies names of the resulting mapped devices in case
14100 there are several. The format is identical to @var{target}.
14103 This must be a @code{mapped-device-kind} object, which specifies how
14104 @var{source} is mapped to @var{target}.
14108 @defvr {Scheme Variable} luks-device-mapping
14109 This defines LUKS block device encryption using the @command{cryptsetup}
14110 command from the package with the same name. It relies on the
14111 @code{dm-crypt} Linux kernel module.
14114 @defvr {Scheme Variable} raid-device-mapping
14115 This defines a RAID device, which is assembled using the @code{mdadm}
14116 command from the package with the same name. It requires a Linux kernel
14117 module for the appropriate RAID level to be loaded, such as @code{raid456}
14118 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
14121 @cindex LVM, logical volume manager
14122 @defvr {Scheme Variable} lvm-device-mapping
14123 This defines one or more logical volumes for the Linux
14124 @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
14125 The volume group is activated by the @command{vgchange} command from the
14126 @code{lvm2} package.
14129 @cindex disk encryption
14131 The following example specifies a mapping from @file{/dev/sda3} to
14132 @file{/dev/mapper/home} using LUKS---the
14133 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
14134 standard mechanism for disk encryption.
14135 The @file{/dev/mapper/home}
14136 device can then be used as the @code{device} of a @code{file-system}
14137 declaration (@pxref{File Systems}).
14141 (source "/dev/sda3")
14143 (type luks-device-mapping))
14146 Alternatively, to become independent of device numbering, one may obtain
14147 the LUKS UUID (@dfn{unique identifier}) of the source device by a
14151 cryptsetup luksUUID /dev/sda3
14154 and use it as follows:
14158 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
14160 (type luks-device-mapping))
14163 @cindex swap encryption
14164 It is also desirable to encrypt swap space, since swap space may contain
14165 sensitive data. One way to accomplish that is to use a swap file in a
14166 file system on a device mapped via LUKS encryption. In this way, the
14167 swap file is encrypted because the entire device is encrypted.
14168 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
14170 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
14171 may be declared as follows:
14175 (source (list "/dev/sda1" "/dev/sdb1"))
14176 (target "/dev/md0")
14177 (type raid-device-mapping))
14180 The @file{/dev/md0} device can then be used as the @code{device} of a
14181 @code{file-system} declaration (@pxref{File Systems}).
14182 Note that the RAID level need not be given; it is chosen during the
14183 initial creation and formatting of the RAID device and is determined
14184 automatically later.
14186 LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
14187 be declared as follows:
14192 (targets (list "vg0-alpha" "vg0-beta"))
14193 (type lvm-device-mapping))
14196 Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
14197 then be used as the @code{device} of a @code{file-system} declaration
14198 (@pxref{File Systems}).
14200 @node User Accounts
14201 @section User Accounts
14205 @cindex user accounts
14206 User accounts and groups are entirely managed through the
14207 @code{operating-system} declaration. They are specified with the
14208 @code{user-account} and @code{user-group} forms:
14214 (supplementary-groups '("wheel" ;allow use of sudo, etc.
14215 "audio" ;sound card
14216 "video" ;video devices such as webcams
14217 "cdrom")) ;the good ol' CD-ROM
14218 (comment "Bob's sister"))
14221 Here's a user account that uses a different shell and a custom home
14222 directory (the default would be @file{"/home/bob"}):
14228 (comment "Alice's bro")
14229 (shell (file-append zsh "/bin/zsh"))
14230 (home-directory "/home/robert"))
14233 When booting or upon completion of @command{guix system reconfigure},
14234 the system ensures that only the user accounts and groups specified in
14235 the @code{operating-system} declaration exist, and with the specified
14236 properties. Thus, account or group creations or modifications made by
14237 directly invoking commands such as @command{useradd} are lost upon
14238 reconfiguration or reboot. This ensures that the system remains exactly
14241 @deftp {Data Type} user-account
14242 Objects of this type represent user accounts. The following members may
14247 The name of the user account.
14251 This is the name (a string) or identifier (a number) of the user group
14252 this account belongs to.
14254 @item @code{supplementary-groups} (default: @code{'()})
14255 Optionally, this can be defined as a list of group names that this
14256 account belongs to.
14258 @item @code{uid} (default: @code{#f})
14259 This is the user ID for this account (a number), or @code{#f}. In the
14260 latter case, a number is automatically chosen by the system when the
14261 account is created.
14263 @item @code{comment} (default: @code{""})
14264 A comment about the account, such as the account owner's full name.
14266 @item @code{home-directory}
14267 This is the name of the home directory for the account.
14269 @item @code{create-home-directory?} (default: @code{#t})
14270 Indicates whether the home directory of this account should be created
14271 if it does not exist yet.
14273 @item @code{shell} (default: Bash)
14274 This is a G-expression denoting the file name of a program to be used as
14275 the shell (@pxref{G-Expressions}). For example, you would refer to the
14276 Bash executable like this:
14279 (file-append bash "/bin/bash")
14283 ... and to the Zsh executable like that:
14286 (file-append zsh "/bin/zsh")
14289 @item @code{system?} (default: @code{#f})
14290 This Boolean value indicates whether the account is a ``system''
14291 account. System accounts are sometimes treated specially; for instance,
14292 graphical login managers do not list them.
14294 @anchor{user-account-password}
14295 @cindex password, for user accounts
14296 @item @code{password} (default: @code{#f})
14297 You would normally leave this field to @code{#f}, initialize user
14298 passwords as @code{root} with the @command{passwd} command, and then let
14299 users change it with @command{passwd}. Passwords set with
14300 @command{passwd} are of course preserved across reboot and
14303 If you @emph{do} want to set an initial password for an account, then
14304 this field must contain the encrypted password, as a string. You can use the
14305 @code{crypt} procedure for this purpose:
14312 ;; Specify a SHA-512-hashed initial password.
14313 (password (crypt "InitialPassword!" "$6$abc")))
14317 The hash of this initial password will be available in a file in
14318 @file{/gnu/store}, readable by all the users, so this method must be used with
14322 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
14323 more information on password encryption, and @ref{Encryption,,, guile, GNU
14324 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
14330 User group declarations are even simpler:
14333 (user-group (name "students"))
14336 @deftp {Data Type} user-group
14337 This type is for, well, user groups. There are just a few fields:
14341 The name of the group.
14343 @item @code{id} (default: @code{#f})
14344 The group identifier (a number). If @code{#f}, a new number is
14345 automatically allocated when the group is created.
14347 @item @code{system?} (default: @code{#f})
14348 This Boolean value indicates whether the group is a ``system'' group.
14349 System groups have low numerical IDs.
14351 @item @code{password} (default: @code{#f})
14352 What, user groups can have a password? Well, apparently yes. Unless
14353 @code{#f}, this field specifies the password of the group.
14358 For convenience, a variable lists all the basic user groups one may
14361 @defvr {Scheme Variable} %base-groups
14362 This is the list of basic user groups that users and/or packages expect
14363 to be present on the system. This includes groups such as ``root'',
14364 ``wheel'', and ``users'', as well as groups used to control access to
14365 specific devices such as ``audio'', ``disk'', and ``cdrom''.
14368 @defvr {Scheme Variable} %base-user-accounts
14369 This is the list of basic system accounts that programs may expect to
14370 find on a GNU/Linux system, such as the ``nobody'' account.
14372 Note that the ``root'' account is not included here. It is a
14373 special-case and is automatically added whether or not it is specified.
14376 @node Keyboard Layout
14377 @section Keyboard Layout
14379 @cindex keyboard layout
14381 To specify what each key of your keyboard does, you need to tell the operating
14382 system what @dfn{keyboard layout} you want to use. The default, when nothing
14383 is specified, is the US English QWERTY layout for 105-key PC keyboards.
14384 However, German speakers will usually prefer the German QWERTZ layout, French
14385 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
14386 or bépo, and they might even want to further customize the effect of some of
14387 the keys. This section explains how to get that done.
14389 @cindex keyboard layout, definition
14390 There are three components that will want to know about your keyboard layout:
14394 The @emph{bootloader} may want to know what keyboard layout you want to use
14395 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
14396 you want, for instance, to make sure that you can type the passphrase of your
14397 encrypted root partition using the right layout.
14400 The @emph{operating system kernel}, Linux, will need that so that the console
14401 is properly configured (@pxref{operating-system Reference,
14402 @code{keyboard-layout}}).
14405 The @emph{graphical display server}, usually Xorg, also has its own idea of
14406 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
14409 Guix allows you to configure all three separately but, fortunately, it allows
14410 you to share the same keyboard layout for all three components.
14412 @cindex XKB, keyboard layouts
14413 Keyboard layouts are represented by records created by the
14414 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
14415 the X Keyboard extension (XKB), each layout has four attributes: a name (often
14416 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
14417 optional variant name, an optional keyboard model name, and a possibly empty
14418 list of additional options. In most cases the layout name is all you care
14421 @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
14422 [#:model] [#:options '()]
14423 Return a new keyboard layout with the given @var{name} and @var{variant}.
14425 @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
14426 string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
14427 @code{xkeyboard-config} package for valid options.
14430 Here are a few examples:
14433 ;; The German QWERTZ layout. Here we assume a standard
14434 ;; "pc105" keyboard model.
14435 (keyboard-layout "de")
14437 ;; The bépo variant of the French layout.
14438 (keyboard-layout "fr" "bepo")
14440 ;; The Catalan layout.
14441 (keyboard-layout "es" "cat")
14443 ;; Arabic layout with "Alt-Shift" to switch to US layout.
14444 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
14446 ;; The Latin American Spanish layout. In addition, the
14447 ;; "Caps Lock" key is used as an additional "Ctrl" key,
14448 ;; and the "Menu" key is used as a "Compose" key to enter
14449 ;; accented letters.
14450 (keyboard-layout "latam"
14451 #:options '("ctrl:nocaps" "compose:menu"))
14453 ;; The Russian layout for a ThinkPad keyboard.
14454 (keyboard-layout "ru" #:model "thinkpad")
14456 ;; The "US international" layout, which is the US layout plus
14457 ;; dead keys to enter accented characters. This is for an
14458 ;; Apple MacBook keyboard.
14459 (keyboard-layout "us" "intl" #:model "macbook78")
14462 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
14463 for a complete list of supported layouts, variants, and models.
14465 @cindex keyboard layout, configuration
14466 Let's say you want your system to use the Turkish keyboard layout throughout
14467 your system---bootloader, console, and Xorg. Here's what your system
14468 configuration would look like:
14470 @findex set-xorg-configuration
14472 ;; Using the Turkish layout for the bootloader, the console,
14477 (keyboard-layout (keyboard-layout "tr")) ;for the console
14478 (bootloader (bootloader-configuration
14479 (bootloader grub-efi-bootloader)
14480 (target "/boot/efi")
14481 (keyboard-layout keyboard-layout))) ;for GRUB
14482 (services (cons (set-xorg-configuration
14483 (xorg-configuration ;for Xorg
14484 (keyboard-layout keyboard-layout)))
14485 %desktop-services)))
14488 In the example above, for GRUB and for Xorg, we just refer to the
14489 @code{keyboard-layout} field defined above, but we could just as well refer to
14490 a different layout. The @code{set-xorg-configuration} procedure communicates
14491 the desired Xorg configuration to the graphical log-in manager, by default
14494 We've discussed how to specify the @emph{default} keyboard layout of your
14495 system when it starts, but you can also adjust it at run time:
14499 If you're using GNOME, its settings panel has a ``Region & Language'' entry
14500 where you can select one or more keyboard layouts.
14503 Under Xorg, the @command{setxkbmap} command (from the same-named package)
14504 allows you to change the current layout. For example, this is how you would
14505 change the layout to US Dvorak:
14508 setxkbmap us dvorak
14512 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
14513 console. However, note that @code{loadkeys} does @emph{not} use the XKB
14514 keyboard layout categorization described above. The command below loads the
14515 French bépo layout:
14526 A @dfn{locale} defines cultural conventions for a particular language
14527 and region of the world (@pxref{Locales,,, libc, The GNU C Library
14528 Reference Manual}). Each locale has a name that typically has the form
14529 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
14530 @code{fr_LU.utf8} designates the locale for the French language, with
14531 cultural conventions from Luxembourg, and using the UTF-8 encoding.
14533 @cindex locale definition
14534 Usually, you will want to specify the default locale for the machine
14535 using the @code{locale} field of the @code{operating-system} declaration
14536 (@pxref{operating-system Reference, @code{locale}}).
14538 The selected locale is automatically added to the @dfn{locale
14539 definitions} known to the system if needed, with its codeset inferred
14540 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
14541 @code{UTF-8} codeset. Additional locale definitions can be specified in
14542 the @code{locale-definitions} slot of @code{operating-system}---this is
14543 useful, for instance, if the codeset could not be inferred from the
14544 locale name. The default set of locale definitions includes some widely
14545 used locales, but not all the available locales, in order to save space.
14547 For instance, to add the North Frisian locale for Germany, the value of
14551 (cons (locale-definition
14552 (name "fy_DE.utf8") (source "fy_DE"))
14553 %default-locale-definitions)
14556 Likewise, to save space, one might want @code{locale-definitions} to
14557 list only the locales that are actually used, as in:
14560 (list (locale-definition
14561 (name "ja_JP.eucjp") (source "ja_JP")
14562 (charset "EUC-JP")))
14566 The compiled locale definitions are available at
14567 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
14568 version, which is the default location where the GNU@tie{}libc provided
14569 by Guix looks for locale data. This can be overridden using the
14570 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
14571 @env{LOCPATH} and locale packages}).
14573 The @code{locale-definition} form is provided by the @code{(gnu system
14574 locale)} module. Details are given below.
14576 @deftp {Data Type} locale-definition
14577 This is the data type of a locale definition.
14582 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
14583 Reference Manual}, for more information on locale names.
14585 @item @code{source}
14586 The name of the source for that locale. This is typically the
14587 @code{@var{language}_@var{territory}} part of the locale name.
14589 @item @code{charset} (default: @code{"UTF-8"})
14590 The ``character set'' or ``code set'' for that locale,
14591 @uref{https://www.iana.org/assignments/character-sets, as defined by
14597 @defvr {Scheme Variable} %default-locale-definitions
14598 A list of commonly used UTF-8 locales, used as the default
14599 value of the @code{locale-definitions} field of @code{operating-system}
14602 @cindex locale name
14603 @cindex normalized codeset in locale names
14604 These locale definitions use the @dfn{normalized codeset} for the part
14605 that follows the dot in the name (@pxref{Using gettextized software,
14606 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
14607 instance it has @code{uk_UA.utf8} but @emph{not}, say,
14608 @code{uk_UA.UTF-8}.
14611 @subsection Locale Data Compatibility Considerations
14613 @cindex incompatibility, of locale data
14614 @code{operating-system} declarations provide a @code{locale-libcs} field
14615 to specify the GNU@tie{}libc packages that are used to compile locale
14616 declarations (@pxref{operating-system Reference}). ``Why would I
14617 care?'', you may ask. Well, it turns out that the binary format of
14618 locale data is occasionally incompatible from one libc version to
14621 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
14622 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
14623 For instance, a program linked against libc version 2.21 is unable to
14624 read locale data produced with libc 2.22; worse, that program
14625 @emph{aborts} instead of simply ignoring the incompatible locale
14626 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
14627 the incompatible locale data, which is already an improvement.}.
14628 Similarly, a program linked against libc 2.22 can read most, but not
14629 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
14630 data is incompatible); thus calls to @code{setlocale} may fail, but
14631 programs will not abort.
14633 The ``problem'' with Guix is that users have a lot of freedom: They can
14634 choose whether and when to upgrade software in their profiles, and might
14635 be using a libc version different from the one the system administrator
14636 used to build the system-wide locale data.
14638 Fortunately, unprivileged users can also install their own locale data
14639 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
14640 @env{GUIX_LOCPATH} and locale packages}).
14642 Still, it is best if the system-wide locale data at
14643 @file{/run/current-system/locale} is built for all the libc versions
14644 actually in use on the system, so that all the programs can access
14645 it---this is especially crucial on a multi-user system. To do that, the
14646 administrator can specify several libc packages in the
14647 @code{locale-libcs} field of @code{operating-system}:
14650 (use-package-modules base)
14654 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
14657 This example would lead to a system containing locale definitions for
14658 both libc 2.21 and the current version of libc in
14659 @file{/run/current-system/locale}.
14665 @cindex system services
14666 An important part of preparing an @code{operating-system} declaration is
14667 listing @dfn{system services} and their configuration (@pxref{Using the
14668 Configuration System}). System services are typically daemons launched
14669 when the system boots, or other actions needed at that time---e.g.,
14670 configuring network access.
14672 Guix has a broad definition of ``service'' (@pxref{Service
14673 Composition}), but many services are managed by the GNU@tie{}Shepherd
14674 (@pxref{Shepherd Services}). On a running system, the @command{herd}
14675 command allows you to list the available services, show their status,
14676 start and stop them, or do other specific operations (@pxref{Jump
14677 Start,,, shepherd, The GNU Shepherd Manual}). For example:
14683 The above command, run as @code{root}, lists the currently defined
14684 services. The @command{herd doc} command shows a synopsis of the given
14685 service and its associated actions:
14689 Run libc's name service cache daemon (nscd).
14691 # herd doc nscd action invalidate
14692 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
14695 The @command{start}, @command{stop}, and @command{restart} sub-commands
14696 have the effect you would expect. For instance, the commands below stop
14697 the nscd service and restart the Xorg display server:
14701 Service nscd has been stopped.
14702 # herd restart xorg-server
14703 Service xorg-server has been stopped.
14704 Service xorg-server has been started.
14707 The following sections document the available services, starting with
14708 the core services, that may be used in an @code{operating-system}
14712 * Base Services:: Essential system services.
14713 * Scheduled Job Execution:: The mcron service.
14714 * Log Rotation:: The rottlog service.
14715 * Networking Services:: Network setup, SSH daemon, etc.
14716 * Unattended Upgrades:: Automated system upgrades.
14717 * X Window:: Graphical display.
14718 * Printing Services:: Local and remote printer support.
14719 * Desktop Services:: D-Bus and desktop services.
14720 * Sound Services:: ALSA and Pulseaudio services.
14721 * Database Services:: SQL databases, key-value stores, etc.
14722 * Mail Services:: IMAP, POP3, SMTP, and all that.
14723 * Messaging Services:: Messaging services.
14724 * Telephony Services:: Telephony services.
14725 * File-Sharing Services:: File-sharing services.
14726 * Monitoring Services:: Monitoring services.
14727 * Kerberos Services:: Kerberos services.
14728 * LDAP Services:: LDAP services.
14729 * Web Services:: Web servers.
14730 * Certificate Services:: TLS certificates via Let's Encrypt.
14731 * DNS Services:: DNS daemons.
14732 * VPN Services:: VPN daemons.
14733 * Network File System:: NFS related services.
14734 * Continuous Integration:: The Cuirass service.
14735 * Power Management Services:: Extending battery life.
14736 * Audio Services:: The MPD.
14737 * Virtualization Services:: Virtualization services.
14738 * Version Control Services:: Providing remote access to Git repositories.
14739 * Game Services:: Game servers.
14740 * PAM Mount Service:: Service to mount volumes when logging in.
14741 * Guix Services:: Services relating specifically to Guix.
14742 * Linux Services:: Services tied to the Linux kernel.
14743 * Hurd Services:: Services specific for a Hurd System.
14744 * Miscellaneous Services:: Other services.
14747 @node Base Services
14748 @subsection Base Services
14750 The @code{(gnu services base)} module provides definitions for the basic
14751 services that one expects from the system. The services exported by
14752 this module are listed below.
14754 @defvr {Scheme Variable} %base-services
14755 This variable contains a list of basic services (@pxref{Service Types
14756 and Services}, for more information on service objects) one would
14757 expect from the system: a login service (mingetty) on each tty, syslogd,
14758 the libc name service cache daemon (nscd), the udev device manager, and
14761 This is the default value of the @code{services} field of
14762 @code{operating-system} declarations. Usually, when customizing a
14763 system, you will want to append services to @code{%base-services}, like
14767 (append (list (service avahi-service-type)
14768 (service openssh-service-type))
14773 @defvr {Scheme Variable} special-files-service-type
14774 This is the service that sets up ``special files'' such as
14775 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
14777 The value associated with @code{special-files-service-type} services
14778 must be a list of tuples where the first element is the ``special file''
14779 and the second element is its target. By default it is:
14781 @cindex @file{/bin/sh}
14782 @cindex @file{sh}, in @file{/bin}
14784 `(("/bin/sh" ,(file-append bash "/bin/sh")))
14787 @cindex @file{/usr/bin/env}
14788 @cindex @file{env}, in @file{/usr/bin}
14789 If you want to add, say, @code{/usr/bin/env} to your system, you can
14793 `(("/bin/sh" ,(file-append bash "/bin/sh"))
14794 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
14797 Since this is part of @code{%base-services}, you can use
14798 @code{modify-services} to customize the set of special files
14799 (@pxref{Service Reference, @code{modify-services}}). But the simple way
14800 to add a special file is @i{via} the @code{extra-special-file} procedure
14804 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
14805 Use @var{target} as the ``special file'' @var{file}.
14807 For example, adding the following lines to the @code{services} field of
14808 your operating system declaration leads to a @file{/usr/bin/env}
14812 (extra-special-file "/usr/bin/env"
14813 (file-append coreutils "/bin/env"))
14817 @deffn {Scheme Procedure} host-name-service @var{name}
14818 Return a service that sets the host name to @var{name}.
14821 @defvr {Scheme Variable} console-font-service-type
14822 Install the given fonts on the specified ttys (fonts are per
14823 virtual console on the kernel Linux). The value of this service is a list of
14824 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
14825 package or any valid argument to @command{setfont}, as in this example:
14828 `(("tty1" . "LatGrkCyr-8x16")
14829 ("tty2" . ,(file-append
14831 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
14832 ("tty3" . ,(file-append
14834 "/share/consolefonts/ter-132n"))) ; for HDPI
14838 @deffn {Scheme Procedure} login-service @var{config}
14839 Return a service to run login according to @var{config}, a
14840 @code{<login-configuration>} object, which specifies the message of the day,
14841 among other things.
14844 @deftp {Data Type} login-configuration
14845 This is the data type representing the configuration of login.
14850 @cindex message of the day
14851 A file-like object containing the ``message of the day''.
14853 @item @code{allow-empty-passwords?} (default: @code{#t})
14854 Allow empty passwords by default so that first-time users can log in when
14855 the 'root' account has just been created.
14860 @deffn {Scheme Procedure} mingetty-service @var{config}
14861 Return a service to run mingetty according to @var{config}, a
14862 @code{<mingetty-configuration>} object, which specifies the tty to run, among
14866 @deftp {Data Type} mingetty-configuration
14867 This is the data type representing the configuration of Mingetty, which
14868 provides the default implementation of virtual console log-in.
14873 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
14875 @item @code{auto-login} (default: @code{#f})
14876 When true, this field must be a string denoting the user name under
14877 which the system automatically logs in. When it is @code{#f}, a
14878 user name and password must be entered to log in.
14880 @item @code{login-program} (default: @code{#f})
14881 This must be either @code{#f}, in which case the default log-in program
14882 is used (@command{login} from the Shadow tool suite), or a gexp denoting
14883 the name of the log-in program.
14885 @item @code{login-pause?} (default: @code{#f})
14886 When set to @code{#t} in conjunction with @var{auto-login}, the user
14887 will have to press a key before the log-in shell is launched.
14889 @item @code{clear-on-logout?} (default: @code{#t})
14890 When set to @code{#t}, the screen will be cleared after logout.
14892 @item @code{mingetty} (default: @var{mingetty})
14893 The Mingetty package to use.
14898 @deffn {Scheme Procedure} agetty-service @var{config}
14899 Return a service to run agetty according to @var{config}, an
14900 @code{<agetty-configuration>} object, which specifies the tty to run,
14901 among other things.
14904 @deftp {Data Type} agetty-configuration
14905 This is the data type representing the configuration of agetty, which
14906 implements virtual and serial console log-in. See the @code{agetty(8)}
14907 man page for more information.
14912 The name of the console this agetty runs on, as a string---e.g.,
14913 @code{"ttyS0"}. This argument is optional, it will default to
14914 a reasonable default serial port used by the kernel Linux.
14916 For this, if there is a value for an option @code{agetty.tty} in the kernel
14917 command line, agetty will extract the device name of the serial port
14918 from it and use that.
14920 If not and if there is a value for an option @code{console} with a tty in
14921 the Linux command line, agetty will extract the device name of the
14922 serial port from it and use that.
14924 In both cases, agetty will leave the other serial device settings
14925 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
14928 @item @code{baud-rate} (default: @code{#f})
14929 A string containing a comma-separated list of one or more baud rates, in
14932 @item @code{term} (default: @code{#f})
14933 A string containing the value used for the @env{TERM} environment
14936 @item @code{eight-bits?} (default: @code{#f})
14937 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
14940 @item @code{auto-login} (default: @code{#f})
14941 When passed a login name, as a string, the specified user will be logged
14942 in automatically without prompting for their login name or password.
14944 @item @code{no-reset?} (default: @code{#f})
14945 When @code{#t}, don't reset terminal cflags (control modes).
14947 @item @code{host} (default: @code{#f})
14948 This accepts a string containing the ``login_host'', which will be written
14949 into the @file{/var/run/utmpx} file.
14951 @item @code{remote?} (default: @code{#f})
14952 When set to @code{#t} in conjunction with @var{host}, this will add an
14953 @code{-r} fakehost option to the command line of the login program
14954 specified in @var{login-program}.
14956 @item @code{flow-control?} (default: @code{#f})
14957 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
14959 @item @code{no-issue?} (default: @code{#f})
14960 When set to @code{#t}, the contents of the @file{/etc/issue} file will
14961 not be displayed before presenting the login prompt.
14963 @item @code{init-string} (default: @code{#f})
14964 This accepts a string that will be sent to the tty or modem before
14965 sending anything else. It can be used to initialize a modem.
14967 @item @code{no-clear?} (default: @code{#f})
14968 When set to @code{#t}, agetty will not clear the screen before showing
14971 @item @code{login-program} (default: (file-append shadow "/bin/login"))
14972 This must be either a gexp denoting the name of a log-in program, or
14973 unset, in which case the default value is the @command{login} from the
14976 @item @code{local-line} (default: @code{#f})
14977 Control the CLOCAL line flag. This accepts one of three symbols as
14978 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
14979 the default value chosen by agetty is @code{'auto}.
14981 @item @code{extract-baud?} (default: @code{#f})
14982 When set to @code{#t}, instruct agetty to try to extract the baud rate
14983 from the status messages produced by certain types of modems.
14985 @item @code{skip-login?} (default: @code{#f})
14986 When set to @code{#t}, do not prompt the user for a login name. This
14987 can be used with @var{login-program} field to use non-standard login
14990 @item @code{no-newline?} (default: @code{#f})
14991 When set to @code{#t}, do not print a newline before printing the
14992 @file{/etc/issue} file.
14994 @c Is this dangerous only when used with login-program, or always?
14995 @item @code{login-options} (default: @code{#f})
14996 This option accepts a string containing options that are passed to the
14997 login program. When used with the @var{login-program}, be aware that a
14998 malicious user could try to enter a login name containing embedded
14999 options that could be parsed by the login program.
15001 @item @code{login-pause} (default: @code{#f})
15002 When set to @code{#t}, wait for any key before showing the login prompt.
15003 This can be used in conjunction with @var{auto-login} to save memory by
15004 lazily spawning shells.
15006 @item @code{chroot} (default: @code{#f})
15007 Change root to the specified directory. This option accepts a directory
15010 @item @code{hangup?} (default: @code{#f})
15011 Use the Linux system call @code{vhangup} to do a virtual hangup of the
15012 specified terminal.
15014 @item @code{keep-baud?} (default: @code{#f})
15015 When set to @code{#t}, try to keep the existing baud rate. The baud
15016 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
15019 @item @code{timeout} (default: @code{#f})
15020 When set to an integer value, terminate if no user name could be read
15021 within @var{timeout} seconds.
15023 @item @code{detect-case?} (default: @code{#f})
15024 When set to @code{#t}, turn on support for detecting an uppercase-only
15025 terminal. This setting will detect a login name containing only
15026 uppercase letters as indicating an uppercase-only terminal and turn on
15027 some upper-to-lower case conversions. Note that this will not support
15028 Unicode characters.
15030 @item @code{wait-cr?} (default: @code{#f})
15031 When set to @code{#t}, wait for the user or modem to send a
15032 carriage-return or linefeed character before displaying
15033 @file{/etc/issue} or login prompt. This is typically used with the
15034 @var{init-string} option.
15036 @item @code{no-hints?} (default: @code{#f})
15037 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
15040 @item @code{no-hostname?} (default: @code{#f})
15041 By default, the hostname is printed. When this option is set to
15042 @code{#t}, no hostname will be shown at all.
15044 @item @code{long-hostname?} (default: @code{#f})
15045 By default, the hostname is only printed until the first dot. When this
15046 option is set to @code{#t}, the fully qualified hostname by
15047 @code{gethostname} or @code{getaddrinfo} is shown.
15049 @item @code{erase-characters} (default: @code{#f})
15050 This option accepts a string of additional characters that should be
15051 interpreted as backspace when the user types their login name.
15053 @item @code{kill-characters} (default: @code{#f})
15054 This option accepts a string that should be interpreted to mean ``ignore
15055 all previous characters'' (also called a ``kill'' character) when the user
15056 types their login name.
15058 @item @code{chdir} (default: @code{#f})
15059 This option accepts, as a string, a directory path that will be changed
15062 @item @code{delay} (default: @code{#f})
15063 This options accepts, as an integer, the number of seconds to sleep
15064 before opening the tty and displaying the login prompt.
15066 @item @code{nice} (default: @code{#f})
15067 This option accepts, as an integer, the nice value with which to run the
15068 @command{login} program.
15070 @item @code{extra-options} (default: @code{'()})
15071 This option provides an ``escape hatch'' for the user to provide arbitrary
15072 command-line arguments to @command{agetty} as a list of strings.
15077 @deffn {Scheme Procedure} kmscon-service-type @var{config}
15078 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
15079 according to @var{config}, a @code{<kmscon-configuration>} object, which
15080 specifies the tty to run, among other things.
15083 @deftp {Data Type} kmscon-configuration
15084 This is the data type representing the configuration of Kmscon, which
15085 implements virtual console log-in.
15089 @item @code{virtual-terminal}
15090 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
15092 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
15093 A gexp denoting the name of the log-in program. The default log-in program is
15094 @command{login} from the Shadow tool suite.
15096 @item @code{login-arguments} (default: @code{'("-p")})
15097 A list of arguments to pass to @command{login}.
15099 @item @code{auto-login} (default: @code{#f})
15100 When passed a login name, as a string, the specified user will be logged
15101 in automatically without prompting for their login name or password.
15103 @item @code{hardware-acceleration?} (default: #f)
15104 Whether to use hardware acceleration.
15106 @item @code{kmscon} (default: @var{kmscon})
15107 The Kmscon package to use.
15112 @cindex name service cache daemon
15114 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
15115 [#:name-services '()]
15116 Return a service that runs the libc name service cache daemon (nscd) with the
15117 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
15118 Service Switch}, for an example.
15120 For convenience, the Shepherd service for nscd provides the following actions:
15124 @cindex cache invalidation, nscd
15125 @cindex nscd, cache invalidation
15126 This invalidate the given cache. For instance, running:
15129 herd invalidate nscd hosts
15133 invalidates the host name lookup cache of nscd.
15136 Running @command{herd statistics nscd} displays information about nscd usage
15142 @defvr {Scheme Variable} %nscd-default-configuration
15143 This is the default @code{<nscd-configuration>} value (see below) used
15144 by @code{nscd-service}. It uses the caches defined by
15145 @code{%nscd-default-caches}; see below.
15148 @deftp {Data Type} nscd-configuration
15149 This is the data type representing the name service cache daemon (nscd)
15154 @item @code{name-services} (default: @code{'()})
15155 List of packages denoting @dfn{name services} that must be visible to
15156 the nscd---e.g., @code{(list @var{nss-mdns})}.
15158 @item @code{glibc} (default: @var{glibc})
15159 Package object denoting the GNU C Library providing the @command{nscd}
15162 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
15163 Name of the nscd log file. This is where debugging output goes when
15164 @code{debug-level} is strictly positive.
15166 @item @code{debug-level} (default: @code{0})
15167 Integer denoting the debugging levels. Higher numbers mean that more
15168 debugging output is logged.
15170 @item @code{caches} (default: @code{%nscd-default-caches})
15171 List of @code{<nscd-cache>} objects denoting things to be cached; see
15177 @deftp {Data Type} nscd-cache
15178 Data type representing a cache database of nscd and its parameters.
15182 @item @code{database}
15183 This is a symbol representing the name of the database to be cached.
15184 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
15185 @code{services}, which designate the corresponding NSS database
15186 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
15188 @item @code{positive-time-to-live}
15189 @itemx @code{negative-time-to-live} (default: @code{20})
15190 A number representing the number of seconds during which a positive or
15191 negative lookup result remains in cache.
15193 @item @code{check-files?} (default: @code{#t})
15194 Whether to check for updates of the files corresponding to
15197 For instance, when @var{database} is @code{hosts}, setting this flag
15198 instructs nscd to check for updates in @file{/etc/hosts} and to take
15201 @item @code{persistent?} (default: @code{#t})
15202 Whether the cache should be stored persistently on disk.
15204 @item @code{shared?} (default: @code{#t})
15205 Whether the cache should be shared among users.
15207 @item @code{max-database-size} (default: 32@tie{}MiB)
15208 Maximum size in bytes of the database cache.
15210 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
15211 @c settings, so leave them out.
15216 @defvr {Scheme Variable} %nscd-default-caches
15217 List of @code{<nscd-cache>} objects used by default by
15218 @code{nscd-configuration} (see above).
15220 It enables persistent and aggressive caching of service and host name
15221 lookups. The latter provides better host name lookup performance,
15222 resilience in the face of unreliable name servers, and also better
15223 privacy---often the result of host name lookups is in local cache, so
15224 external name servers do not even need to be queried.
15227 @anchor{syslog-configuration-type}
15230 @deftp {Data Type} syslog-configuration
15231 This data type represents the configuration of the syslog daemon.
15234 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
15235 The syslog daemon to use.
15237 @item @code{config-file} (default: @code{%default-syslog.conf})
15238 The syslog configuration file to use.
15243 @anchor{syslog-service}
15245 @deffn {Scheme Procedure} syslog-service @var{config}
15246 Return a service that runs a syslog daemon according to @var{config}.
15248 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
15249 information on the configuration file syntax.
15252 @defvr {Scheme Variable} guix-service-type
15253 This is the type of the service that runs the build daemon,
15254 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
15255 @code{guix-configuration} record as described below.
15258 @anchor{guix-configuration-type}
15259 @deftp {Data Type} guix-configuration
15260 This data type represents the configuration of the Guix build daemon.
15261 @xref{Invoking guix-daemon}, for more information.
15264 @item @code{guix} (default: @var{guix})
15265 The Guix package to use.
15267 @item @code{build-group} (default: @code{"guixbuild"})
15268 Name of the group for build user accounts.
15270 @item @code{build-accounts} (default: @code{10})
15271 Number of build user accounts to create.
15273 @item @code{authorize-key?} (default: @code{#t})
15274 @cindex substitutes, authorization thereof
15275 Whether to authorize the substitute keys listed in
15276 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
15277 (@pxref{Substitutes}).
15279 When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
15280 changed by invoking @command{guix archive --authorize}. You must
15281 instead adjust @code{guix-configuration} as you wish and reconfigure the
15282 system. This ensures that your operating system configuration file is
15286 When booting or reconfiguring to a system where @code{authorize-key?}
15287 is true, the existing @file{/etc/guix/acl} file is backed up as
15288 @file{/etc/guix/acl.bak} if it was determined to be a manually modified
15289 file. This is to facilitate migration from earlier versions, which
15290 allowed for in-place modifications to @file{/etc/guix/acl}.
15293 @vindex %default-authorized-guix-keys
15294 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
15295 The list of authorized key files for archive imports, as a list of
15296 string-valued gexps (@pxref{Invoking guix archive}). By default, it
15297 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
15298 See @code{substitute-urls} below for an example on how to change it.
15300 @item @code{use-substitutes?} (default: @code{#t})
15301 Whether to use substitutes.
15303 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
15304 The list of URLs where to look for substitutes by default.
15306 Suppose you would like to fetch substitutes from @code{guix.example.org}
15307 in addition to @code{@value{SUBSTITUTE-SERVER}}. You will need to do
15308 two things: (1) add @code{guix.example.org} to @code{substitute-urls},
15309 and (2) authorize its signing key, having done appropriate checks
15310 (@pxref{Substitute Server Authorization}). The configuration below does
15314 (guix-configuration
15316 (append (list "https://guix.example.org")
15317 %default-substitute-urls))
15319 (append (list (local-file "./guix.example.org-key.pub"))
15320 %default-authorized-guix-keys)))
15323 This example assumes that the file @file{./guix.example.org-key.pub}
15324 contains the public key that @code{guix.example.org} uses to sign
15327 @item @code{max-silent-time} (default: @code{0})
15328 @itemx @code{timeout} (default: @code{0})
15329 The number of seconds of silence and the number of seconds of activity,
15330 respectively, after which a build process times out. A value of zero
15331 disables the timeout.
15333 @item @code{log-compression} (default: @code{'bzip2})
15334 The type of compression used for build logs---one of @code{gzip},
15335 @code{bzip2}, or @code{none}.
15337 @item @code{discover?} (default: @code{#f})
15338 Whether to discover substitute servers on the local network using mDNS
15341 @item @code{extra-options} (default: @code{'()})
15342 List of extra command-line options for @command{guix-daemon}.
15344 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
15345 File where @command{guix-daemon}'s standard output and standard error
15348 @cindex HTTP proxy, for @code{guix-daemon}
15349 @cindex proxy, for @code{guix-daemon} HTTP access
15350 @item @code{http-proxy} (default: @code{#f})
15351 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
15352 derivations and substitutes.
15354 It is also possible to change the daemon's proxy at run time through the
15355 @code{set-http-proxy} action, which restarts it:
15358 herd set-http-proxy guix-daemon http://localhost:8118
15361 To clear the proxy settings, run:
15364 herd set-http-proxy guix-daemon
15367 @item @code{tmpdir} (default: @code{#f})
15368 A directory path where the @command{guix-daemon} will perform builds.
15373 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
15374 Run @var{udev}, which populates the @file{/dev} directory dynamically.
15375 udev rules can be provided as a list of files through the @var{rules}
15376 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
15377 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
15378 creation of such rule files.
15380 The @command{herd rules udev} command, as root, returns the name of the
15381 directory containing all the active udev rules.
15384 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
15385 Return a udev-rule file named @var{file-name} containing the rules
15386 defined by the @var{contents} literal.
15388 In the following example, a rule for a USB device is defined to be
15389 stored in the file @file{90-usb-thing.rules}. The rule runs a script
15390 upon detecting a USB device with a given product identifier.
15393 (define %example-udev-rule
15395 "90-usb-thing.rules"
15396 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
15397 "ATTR@{product@}==\"Example\", "
15398 "RUN+=\"/path/to/script\"")))
15402 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
15403 [#:groups @var{groups}]
15404 Return a service that extends @code{udev-service-type } with @var{rules}
15405 and @code{account-service-type} with @var{groups} as system groups.
15406 This works by creating a singleton service type
15407 @code{@var{name}-udev-rules}, of which the returned service is an
15410 Here we show how it can be used to extend @code{udev-service-type} with the
15411 previously defined rule @code{%example-udev-rule}.
15417 (cons (udev-rules-service 'usb-thing %example-udev-rule)
15418 %desktop-services)))
15422 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
15423 Return a udev file named @var{file-name} containing the rules defined
15424 within @var{file}, a file-like object.
15426 The following example showcases how we can use an existing rule file.
15429 (use-modules (guix download) ;for url-fetch
15430 (guix packages) ;for origin
15433 (define %android-udev-rules
15435 "51-android-udev.rules"
15436 (let ((version "20170910"))
15439 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
15440 "android-udev-rules/" version "/51-android.rules"))
15442 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
15446 Additionally, Guix package definitions can be included in @var{rules} in
15447 order to extend the udev rules with the definitions found under their
15448 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
15449 @var{file->udev-rule} example, we could have used the
15450 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
15451 packages android)} module.
15453 The following example shows how to use the @var{android-udev-rules}
15454 package so that the Android tool @command{adb} can detect devices
15455 without root privileges. It also details how to create the
15456 @code{adbusers} group, which is required for the proper functioning of
15457 the rules defined within the @code{android-udev-rules} package. To
15458 create such a group, we must define it both as part of the
15459 @code{supplementary-groups} of our @code{user-account} declaration, as
15460 well as in the @var{groups} of the @code{udev-rules-service} procedure.
15463 (use-modules (gnu packages android) ;for android-udev-rules
15464 (gnu system shadow) ;for user-group
15469 (users (cons (user-account
15471 (supplementary-groups
15472 '("adbusers" ;for adb
15473 "wheel" "netdev" "audio" "video")))))
15476 (cons (udev-rules-service 'android android-udev-rules
15477 #:groups '("adbusers"))
15478 %desktop-services)))
15481 @defvr {Scheme Variable} urandom-seed-service-type
15482 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
15483 when rebooting. It also tries to seed @file{/dev/urandom} from
15484 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
15488 @defvr {Scheme Variable} %random-seed-file
15489 This is the name of the file where some random bytes are saved by
15490 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
15491 It defaults to @file{/var/lib/random-seed}.
15496 @defvr {Scheme Variable} gpm-service-type
15497 This is the type of the service that runs GPM, the @dfn{general-purpose
15498 mouse daemon}, which provides mouse support to the Linux console. GPM
15499 allows users to use the mouse in the console, notably to select, copy,
15502 The value for services of this type must be a @code{gpm-configuration}
15503 (see below). This service is not part of @code{%base-services}.
15506 @deftp {Data Type} gpm-configuration
15507 Data type representing the configuration of GPM.
15510 @item @code{options} (default: @code{%default-gpm-options})
15511 Command-line options passed to @command{gpm}. The default set of
15512 options instruct @command{gpm} to listen to mouse events on
15513 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
15516 @item @code{gpm} (default: @code{gpm})
15517 The GPM package to use.
15522 @anchor{guix-publish-service-type}
15523 @deffn {Scheme Variable} guix-publish-service-type
15524 This is the service type for @command{guix publish} (@pxref{Invoking
15525 guix publish}). Its value must be a @code{guix-publish-configuration}
15526 object, as described below.
15528 This assumes that @file{/etc/guix} already contains a signing key pair as
15529 created by @command{guix archive --generate-key} (@pxref{Invoking guix
15530 archive}). If that is not the case, the service will fail to start.
15533 @deftp {Data Type} guix-publish-configuration
15534 Data type representing the configuration of the @code{guix publish}
15538 @item @code{guix} (default: @code{guix})
15539 The Guix package to use.
15541 @item @code{port} (default: @code{80})
15542 The TCP port to listen for connections.
15544 @item @code{host} (default: @code{"localhost"})
15545 The host (and thus, network interface) to listen to. Use
15546 @code{"0.0.0.0"} to listen on all the network interfaces.
15548 @item @code{advertise?} (default: @code{#f})
15549 When true, advertise the service on the local network @i{via} the DNS-SD
15550 protocol, using Avahi.
15552 This allows neighboring Guix devices with discovery on (see
15553 @code{guix-configuration} above) to discover this @command{guix publish}
15554 instance and to automatically download substitutes from it.
15556 @item @code{compression} (default: @code{'(("gzip" 3))})
15557 This is a list of compression method/level tuple used when compressing
15558 substitutes. For example, to compress all substitutes with @emph{both} lzip
15559 at level 7 and gzip at level 9, write:
15562 '(("lzip" 7) ("gzip" 9))
15565 Level 9 achieves the best compression ratio at the expense of increased CPU
15566 usage, whereas level 1 achieves fast compression. @xref{Invoking guix
15567 publish}, for more information on the available compression methods and
15568 the tradeoffs involved.
15570 An empty list disables compression altogether.
15572 @item @code{nar-path} (default: @code{"nar"})
15573 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
15574 publish, @option{--nar-path}}, for details.
15576 @item @code{cache} (default: @code{#f})
15577 When it is @code{#f}, disable caching and instead generate archives on
15578 demand. Otherwise, this should be the name of a directory---e.g.,
15579 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
15580 archives and meta-data ready to be sent. @xref{Invoking guix publish,
15581 @option{--cache}}, for more information on the tradeoffs involved.
15583 @item @code{workers} (default: @code{#f})
15584 When it is an integer, this is the number of worker threads used for
15585 caching; when @code{#f}, the number of processors is used.
15586 @xref{Invoking guix publish, @option{--workers}}, for more information.
15588 @item @code{cache-bypass-threshold} (default: 10 MiB)
15589 When @code{cache} is true, this is the maximum size in bytes of a store
15590 item for which @command{guix publish} may bypass its cache in case of a
15591 cache miss. @xref{Invoking guix publish,
15592 @option{--cache-bypass-threshold}}, for more information.
15594 @item @code{ttl} (default: @code{#f})
15595 When it is an integer, this denotes the @dfn{time-to-live} in seconds
15596 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
15597 for more information.
15601 @anchor{rngd-service}
15602 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
15603 [#:device "/dev/hwrng"]
15604 Return a service that runs the @command{rngd} program from @var{rng-tools}
15605 to add @var{device} to the kernel's entropy pool. The service will fail if
15606 @var{device} does not exist.
15609 @anchor{pam-limits-service}
15610 @cindex session limits
15615 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
15617 Return a service that installs a configuration file for the
15618 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
15619 @code{pam_limits} module}. The procedure optionally takes a list of
15620 @code{pam-limits-entry} values, which can be used to specify
15621 @code{ulimit} limits and nice priority limits to user sessions.
15623 The following limits definition sets two hard and soft limits for all
15624 login sessions of users in the @code{realtime} group:
15627 (pam-limits-service
15629 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
15630 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
15633 The first entry increases the maximum realtime priority for
15634 non-privileged processes; the second entry lifts any restriction of the
15635 maximum address space that can be locked in memory. These settings are
15636 commonly used for real-time audio systems.
15639 @node Scheduled Job Execution
15640 @subsection Scheduled Job Execution
15644 @cindex scheduling jobs
15645 The @code{(gnu services mcron)} module provides an interface to
15646 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
15647 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
15648 Unix @command{cron} daemon; the main difference is that it is
15649 implemented in Guile Scheme, which provides a lot of flexibility when
15650 specifying the scheduling of jobs and their actions.
15652 The example below defines an operating system that runs the
15653 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
15654 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
15655 well as the @command{mkid} command on behalf of an unprivileged user
15656 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
15657 gexps to introduce job definitions that are passed to mcron
15658 (@pxref{G-Expressions}).
15661 (use-modules (guix) (gnu) (gnu services mcron))
15662 (use-package-modules base idutils)
15664 (define updatedb-job
15665 ;; Run 'updatedb' at 3AM every day. Here we write the
15666 ;; job's action as a Scheme procedure.
15667 #~(job '(next-hour '(3))
15669 (execl (string-append #$findutils "/bin/updatedb")
15671 "--prunepaths=/tmp /var/tmp /gnu/store"))))
15673 (define garbage-collector-job
15674 ;; Collect garbage 5 minutes after midnight every day.
15675 ;; The job's action is a shell command.
15676 #~(job "5 0 * * *" ;Vixie cron syntax
15679 (define idutils-job
15680 ;; Update the index database as user "charlie" at 12:15PM
15681 ;; and 19:15PM. This runs from the user's home directory.
15682 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
15683 (string-append #$idutils "/bin/mkid src")
15689 ;; %BASE-SERVICES already includes an instance of
15690 ;; 'mcron-service-type', which we extend with additional
15691 ;; jobs using 'simple-service'.
15692 (services (cons (simple-service 'my-cron-jobs
15694 (list garbage-collector-job
15700 For more complex jobs defined in Scheme where you need control over the top
15701 level, for instance to introduce a @code{use-modules} form, you can move your
15702 code to a separate program using the @code{program-file} procedure of the
15703 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
15707 (define %battery-alert-job
15708 ;; Beep when the battery percentage falls below %MIN-LEVEL.
15710 '(next-minute (range 0 60 1))
15712 "battery-alert.scm"
15713 (with-imported-modules (source-module-closure
15714 '((guix build utils)))
15716 (use-modules (guix build utils)
15719 (ice-9 textual-ports)
15722 (define %min-level 20)
15724 (setenv "LC_ALL" "C") ;ensure English output
15725 (and-let* ((input-pipe (open-pipe*
15727 #$(file-append acpi "/bin/acpi")))
15728 (output (get-string-all input-pipe))
15729 (m (string-match "Discharging, ([0-9]+)%" output))
15730 (level (string->number (match:substring m 1)))
15731 ((< level %min-level)))
15732 (format #t "warning: Battery level is low (~a%)~%" level)
15733 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
15736 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
15737 for more information on mcron job specifications. Below is the
15738 reference of the mcron service.
15740 On a running system, you can use the @code{schedule} action of the service to
15741 visualize the mcron jobs that will be executed next:
15744 # herd schedule mcron
15748 The example above lists the next five tasks that will be executed, but you can
15749 also specify the number of tasks to display:
15752 # herd schedule mcron 10
15755 @defvr {Scheme Variable} mcron-service-type
15756 This is the type of the @code{mcron} service, whose value is an
15757 @code{mcron-configuration} object.
15759 This service type can be the target of a service extension that provides
15760 it additional job specifications (@pxref{Service Composition}). In
15761 other words, it is possible to define services that provide additional
15765 @deftp {Data Type} mcron-configuration
15766 Data type representing the configuration of mcron.
15769 @item @code{mcron} (default: @var{mcron})
15770 The mcron package to use.
15773 This is a list of gexps (@pxref{G-Expressions}), where each gexp
15774 corresponds to an mcron job specification (@pxref{Syntax, mcron job
15775 specifications,, mcron, GNU@tie{}mcron}).
15781 @subsection Log Rotation
15784 @cindex log rotation
15786 Log files such as those found in @file{/var/log} tend to grow endlessly,
15787 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
15788 their contents in separate files, possibly compressed. The @code{(gnu
15789 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
15790 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
15792 This service is part of @code{%base-services}, and thus enabled by
15793 default, with the default settings, for commonly encountered log files.
15794 The example below shows how to extend it with an additional
15795 @dfn{rotation}, should you need to do that (usually, services that
15796 produce log files already take care of that):
15799 (use-modules (guix) (gnu))
15800 (use-service-modules admin)
15802 (define my-log-files
15803 ;; Log files that I want to rotate.
15804 '("/var/log/something.log" "/var/log/another.log"))
15808 (services (cons (simple-service 'rotate-my-stuff
15809 rottlog-service-type
15810 (list (log-rotation
15812 (files my-log-files))))
15816 @defvr {Scheme Variable} rottlog-service-type
15817 This is the type of the Rottlog service, whose value is a
15818 @code{rottlog-configuration} object.
15820 Other services can extend this one with new @code{log-rotation} objects
15821 (see below), thereby augmenting the set of files to be rotated.
15823 This service type can define mcron jobs (@pxref{Scheduled Job
15824 Execution}) to run the rottlog service.
15827 @deftp {Data Type} rottlog-configuration
15828 Data type representing the configuration of rottlog.
15831 @item @code{rottlog} (default: @code{rottlog})
15832 The Rottlog package to use.
15834 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
15835 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
15836 rottlog, GNU Rot[t]log Manual}).
15838 @item @code{rotations} (default: @code{%default-rotations})
15839 A list of @code{log-rotation} objects as defined below.
15842 This is a list of gexps where each gexp corresponds to an mcron job
15843 specification (@pxref{Scheduled Job Execution}).
15847 @deftp {Data Type} log-rotation
15848 Data type representing the rotation of a group of log files.
15850 Taking an example from the Rottlog manual (@pxref{Period Related File
15851 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
15857 (files '("/var/log/apache/*"))
15858 (options '("storedir apache-archives"
15864 The list of fields is as follows:
15867 @item @code{frequency} (default: @code{'weekly})
15868 The log rotation frequency, a symbol.
15871 The list of files or file glob patterns to rotate.
15873 @item @code{options} (default: @code{'()})
15874 The list of rottlog options for this rotation (@pxref{Configuration
15875 parameters,,, rottlog, GNU Rot[t]lg Manual}).
15877 @item @code{post-rotate} (default: @code{#f})
15878 Either @code{#f} or a gexp to execute once the rotation has completed.
15882 @defvr {Scheme Variable} %default-rotations
15883 Specifies weekly rotation of @code{%rotated-files} and of
15884 @file{/var/log/guix-daemon.log}.
15887 @defvr {Scheme Variable} %rotated-files
15888 The list of syslog-controlled files to be rotated. By default it is:
15889 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
15890 "/var/log/maillog")}.
15893 @node Networking Services
15894 @subsection Networking Services
15896 The @code{(gnu services networking)} module provides services to configure
15897 the network interface.
15899 @cindex DHCP, networking service
15900 @defvr {Scheme Variable} dhcp-client-service-type
15901 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
15902 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
15903 is the DHCP client package to use, @code{isc-dhcp} by default.
15906 @deffn {Scheme Procedure} dhcpd-service-type
15907 This type defines a service that runs a DHCP daemon. To create a
15908 service of this type, you must supply a @code{<dhcpd-configuration>}.
15912 (service dhcpd-service-type
15913 (dhcpd-configuration
15914 (config-file (local-file "my-dhcpd.conf"))
15915 (interfaces '("enp0s25"))))
15919 @deftp {Data Type} dhcpd-configuration
15921 @item @code{package} (default: @code{isc-dhcp})
15922 The package that provides the DHCP daemon. This package is expected to
15923 provide the daemon at @file{sbin/dhcpd} relative to its output
15924 directory. The default package is the
15925 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
15926 @item @code{config-file} (default: @code{#f})
15927 The configuration file to use. This is required. It will be passed to
15928 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
15929 object (@pxref{G-Expressions, file-like objects}). See @code{man
15930 dhcpd.conf} for details on the configuration file syntax.
15931 @item @code{version} (default: @code{"4"})
15932 The DHCP version to use. The ISC DHCP server supports the values ``4'',
15933 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
15934 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
15936 @item @code{run-directory} (default: @code{"/run/dhcpd"})
15937 The run directory to use. At service activation time, this directory
15938 will be created if it does not exist.
15939 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
15940 The PID file to use. This corresponds to the @code{-pf} option of
15941 @code{dhcpd}. See @code{man dhcpd} for details.
15942 @item @code{interfaces} (default: @code{'()})
15943 The names of the network interfaces on which dhcpd should listen for
15944 broadcasts. If this list is not empty, then its elements (which must be
15945 strings) will be appended to the @code{dhcpd} invocation when starting
15946 the daemon. It may not be necessary to explicitly specify any
15947 interfaces here; see @code{man dhcpd} for details.
15951 @defvr {Scheme Variable} static-networking-service-type
15952 This is the type for statically-configured network interfaces.
15953 @c TODO Document <static-networking> data structures.
15956 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
15957 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
15958 [#:requirement @code{'(udev)}]
15959 Return a service that starts @var{interface} with address @var{ip}. If
15960 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
15961 it must be a string specifying the default network gateway. @var{requirement}
15962 can be used to declare a dependency on another service before configuring the
15965 This procedure can be called several times, one for each network
15966 interface of interest. Behind the scenes what it does is extend
15967 @code{static-networking-service-type} with additional network interfaces
15973 (static-networking-service "eno1" "192.168.1.82"
15974 #:gateway "192.168.1.2"
15975 #:name-servers '("192.168.1.2"))
15982 @cindex network management
15983 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
15984 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
15985 management daemon that aims to simplify wired and wireless networking.
15987 This service adds the @var{wicd} package to the global profile, providing
15988 several commands to interact with the daemon and configure networking:
15989 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
15990 and @command{wicd-curses} user interfaces.
15993 @cindex ModemManager
15995 @defvr {Scheme Variable} modem-manager-service-type
15996 This is the service type for the
15997 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
15998 service. The value for this service type is a
15999 @code{modem-manager-configuration} record.
16001 This service is part of @code{%desktop-services} (@pxref{Desktop
16005 @deftp {Data Type} modem-manager-configuration
16006 Data type representing the configuration of ModemManager.
16009 @item @code{modem-manager} (default: @code{modem-manager})
16010 The ModemManager package to use.
16015 @cindex USB_ModeSwitch
16016 @cindex Modeswitching
16018 @defvr {Scheme Variable} usb-modeswitch-service-type
16019 This is the service type for the
16020 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch}
16021 service. The value for this service type is
16022 a @code{usb-modeswitch-configuration} record.
16024 When plugged in, some USB modems (and other USB devices) initially present
16025 themselves as a read-only storage medium and not as a modem. They need to be
16026 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
16027 installs udev rules to automatically modeswitch these devices when they are
16030 This service is part of @code{%desktop-services} (@pxref{Desktop
16034 @deftp {Data Type} usb-modeswitch-configuration
16035 Data type representing the configuration of USB_ModeSwitch.
16038 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
16039 The USB_ModeSwitch package providing the binaries for modeswitching.
16041 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
16042 The package providing the device data and udev rules file used by
16045 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
16046 Which config file to use for the USB_ModeSwitch dispatcher. By default the
16047 config file shipped with USB_ModeSwitch is used which disables logging to
16048 @file{/var/log} among other default settings. If set to @code{#f}, no config
16054 @cindex NetworkManager
16056 @defvr {Scheme Variable} network-manager-service-type
16057 This is the service type for the
16058 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
16059 service. The value for this service type is a
16060 @code{network-manager-configuration} record.
16062 This service is part of @code{%desktop-services} (@pxref{Desktop
16066 @deftp {Data Type} network-manager-configuration
16067 Data type representing the configuration of NetworkManager.
16070 @item @code{network-manager} (default: @code{network-manager})
16071 The NetworkManager package to use.
16073 @item @code{dns} (default: @code{"default"})
16074 Processing mode for DNS, which affects how NetworkManager uses the
16075 @code{resolv.conf} configuration file.
16079 NetworkManager will update @code{resolv.conf} to reflect the nameservers
16080 provided by currently active connections.
16083 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
16084 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
16085 then update @code{resolv.conf} to point to the local nameserver.
16087 With this setting, you can share your network connection. For example when
16088 you want to share your network connection to another laptop @i{via} an
16089 Ethernet cable, you can open @command{nm-connection-editor} and configure the
16090 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
16091 and reestablish the connection (or reboot).
16093 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
16094 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
16095 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
16096 browser on your host system, or connect to the VM @i{via} SSH
16097 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
16098 host-to-guest connection, run this command once:
16101 nmcli connection add type tun \
16102 connection.interface-name tap0 \
16103 tun.mode tap tun.owner $(id -u) \
16104 ipv4.method shared \
16105 ipv4.addresses 172.28.112.1/24
16108 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
16109 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
16110 @command{qemu-system-...}.
16113 NetworkManager will not modify @code{resolv.conf}.
16116 @item @code{vpn-plugins} (default: @code{'()})
16117 This is the list of available plugins for virtual private networks
16118 (VPNs). An example of this is the @code{network-manager-openvpn}
16119 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
16125 @deffn {Scheme Variable} connman-service-type
16126 This is the service type to run @url{https://01.org/connman,Connman},
16127 a network connection manager.
16129 Its value must be an
16130 @code{connman-configuration} record as in this example:
16133 (service connman-service-type
16134 (connman-configuration
16135 (disable-vpn? #t)))
16138 See below for details about @code{connman-configuration}.
16141 @deftp {Data Type} connman-configuration
16142 Data Type representing the configuration of connman.
16145 @item @code{connman} (default: @var{connman})
16146 The connman package to use.
16148 @item @code{disable-vpn?} (default: @code{#f})
16149 When true, disable connman's vpn plugin.
16153 @cindex WPA Supplicant
16154 @defvr {Scheme Variable} wpa-supplicant-service-type
16155 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
16156 supplicant}, an authentication daemon required to authenticate against
16157 encrypted WiFi or ethernet networks.
16160 @deftp {Data Type} wpa-supplicant-configuration
16161 Data type representing the configuration of WPA Supplicant.
16163 It takes the following parameters:
16166 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
16167 The WPA Supplicant package to use.
16169 @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
16170 List of services that should be started before WPA Supplicant starts.
16172 @item @code{dbus?} (default: @code{#t})
16173 Whether to listen for requests on D-Bus.
16175 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
16176 Where to store the PID file.
16178 @item @code{interface} (default: @code{#f})
16179 If this is set, it must specify the name of a network interface that
16180 WPA supplicant will control.
16182 @item @code{config-file} (default: @code{#f})
16183 Optional configuration file to use.
16185 @item @code{extra-options} (default: @code{'()})
16186 List of additional command-line arguments to pass to the daemon.
16190 @cindex hostapd service, for Wi-Fi access points
16191 @cindex Wi-Fi access points, hostapd service
16192 @defvr {Scheme Variable} hostapd-service-type
16193 This is the service type to run the @uref{https://w1.fi/hostapd/,
16194 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
16195 authentication servers. Its associated value must be a
16196 @code{hostapd-configuration} as shown below:
16199 ;; Use wlan1 to run the access point for "My Network".
16200 (service hostapd-service-type
16201 (hostapd-configuration
16202 (interface "wlan1")
16203 (ssid "My Network")
16208 @deftp {Data Type} hostapd-configuration
16209 This data type represents the configuration of the hostapd service, with
16210 the following fields:
16213 @item @code{package} (default: @code{hostapd})
16214 The hostapd package to use.
16216 @item @code{interface} (default: @code{"wlan0"})
16217 The network interface to run the WiFi access point.
16220 The SSID (@dfn{service set identifier}), a string that identifies this
16223 @item @code{broadcast-ssid?} (default: @code{#t})
16224 Whether to broadcast this SSID.
16226 @item @code{channel} (default: @code{1})
16227 The WiFi channel to use.
16229 @item @code{driver} (default: @code{"nl80211"})
16230 The driver interface type. @code{"nl80211"} is used with all Linux
16231 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
16232 RADIUS server that does # not control any wireless/wired driver.
16234 @item @code{extra-settings} (default: @code{""})
16235 Extra settings to append as-is to the hostapd configuration file. See
16236 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
16237 configuration file reference.
16241 @defvr {Scheme Variable} simulated-wifi-service-type
16242 This is the type of a service to simulate WiFi networking, which can be
16243 useful in virtual machines for testing purposes. The service loads the
16245 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
16246 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
16247 network that can be seen on @code{wlan0}, by default.
16249 The service's value is a @code{hostapd-configuration} record.
16253 @defvr {Scheme Variable} iptables-service-type
16254 This is the service type to set up an iptables configuration. iptables is a
16255 packet filtering framework supported by the Linux kernel. This service
16256 supports configuring iptables for both IPv4 and IPv6. A simple example
16257 configuration rejecting all incoming connections except those to the ssh port
16261 (service iptables-service-type
16262 (iptables-configuration
16263 (ipv4-rules (plain-file "iptables.rules" "*filter
16267 -A INPUT -p tcp --dport 22 -j ACCEPT
16268 -A INPUT -j REJECT --reject-with icmp-port-unreachable
16271 (ipv6-rules (plain-file "ip6tables.rules" "*filter
16275 -A INPUT -p tcp --dport 22 -j ACCEPT
16276 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
16282 @deftp {Data Type} iptables-configuration
16283 The data type representing the configuration of iptables.
16286 @item @code{iptables} (default: @code{iptables})
16287 The iptables package that provides @code{iptables-restore} and
16288 @code{ip6tables-restore}.
16289 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
16290 The iptables rules to use. It will be passed to @code{iptables-restore}.
16291 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
16293 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
16294 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
16295 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
16301 @defvr {Scheme Variable} nftables-service-type
16302 This is the service type to set up a nftables configuration. nftables is a
16303 netfilter project that aims to replace the existing iptables, ip6tables,
16304 arptables and ebtables framework. It provides a new packet filtering
16305 framework, a new user-space utility @command{nft}, and a compatibility layer
16306 for iptables. This service comes with a default ruleset
16307 @code{%default-nftables-ruleset} that rejecting all incomming connections
16308 except those to the ssh port 22. To use it, simply write:
16311 (service nftables-service-type)
16315 @deftp {Data Type} nftables-configuration
16316 The data type representing the configuration of nftables.
16319 @item @code{package} (default: @code{nftables})
16320 The nftables package that provides @command{nft}.
16321 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
16322 The nftables ruleset to use. This may be any ``file-like'' object
16323 (@pxref{G-Expressions, file-like objects}).
16327 @cindex NTP (Network Time Protocol), service
16328 @cindex ntpd, service for the Network Time Protocol daemon
16329 @cindex real time clock
16330 @defvr {Scheme Variable} ntp-service-type
16331 This is the type of the service running the @uref{https://www.ntp.org,
16332 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
16333 system clock synchronized with that of the specified NTP servers.
16335 The value of this service is an @code{ntpd-configuration} object, as described
16339 @deftp {Data Type} ntp-configuration
16340 This is the data type for the NTP service configuration.
16343 @item @code{servers} (default: @code{%ntp-servers})
16344 This is the list of servers (@code{<ntp-server>} records) with which
16345 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
16348 @item @code{allow-large-adjustment?} (default: @code{#t})
16349 This determines whether @command{ntpd} is allowed to make an initial
16350 adjustment of more than 1,000 seconds.
16352 @item @code{ntp} (default: @code{ntp})
16353 The NTP package to use.
16357 @defvr {Scheme Variable} %ntp-servers
16358 List of host names used as the default NTP servers. These are servers of the
16359 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
16362 @deftp {Data Type} ntp-server
16363 The data type representing the configuration of a NTP server.
16366 @item @code{type} (default: @code{'server})
16367 The type of the NTP server, given as a symbol. One of @code{'pool},
16368 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
16370 @item @code{address}
16371 The address of the server, as a string.
16373 @item @code{options}
16374 NTPD options to use with that specific server, given as a list of option names
16375 and/or of option names and values tuples. The following example define a server
16376 to use with the options @option{iburst} and @option{prefer}, as well as
16377 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
16382 (address "some.ntp.server.org")
16383 (options `(iburst (version 3) (maxpoll 16) prefer))))
16389 @deffn {Scheme Procedure} openntpd-service-type
16390 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
16391 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
16392 clock synchronized with that of the given servers.
16396 openntpd-service-type
16397 (openntpd-configuration
16398 (listen-on '("127.0.0.1" "::1"))
16399 (sensor '("udcf0 correction 70000"))
16400 (constraint-from '("www.gnu.org"))
16401 (constraints-from '("https://www.google.com/"))))
16406 @defvr {Scheme Variable} %openntpd-servers
16407 This variable is a list of the server addresses defined in
16408 @code{%ntp-servers}.
16411 @deftp {Data Type} openntpd-configuration
16413 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
16414 The openntpd executable to use.
16415 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
16416 A list of local IP addresses or hostnames the ntpd daemon should listen on.
16417 @item @code{query-from} (default: @code{'()})
16418 A list of local IP address the ntpd daemon should use for outgoing queries.
16419 @item @code{sensor} (default: @code{'()})
16420 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
16421 will listen to each sensor that actually exists and ignore non-existent ones.
16422 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
16424 @item @code{server} (default: @code{'()})
16425 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
16426 @item @code{servers} (default: @code{%openntp-servers})
16427 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
16428 @item @code{constraint-from} (default: @code{'()})
16429 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
16430 This time information is not used for precision but acts as an authenticated
16431 constraint, thereby reducing the impact of unauthenticated NTP
16432 man-in-the-middle attacks.
16433 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
16435 @item @code{constraints-from} (default: @code{'()})
16436 As with constraint from, specify a list of URLs, IP addresses or hostnames of
16437 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
16438 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
16443 @deffn {Scheme variable} inetd-service-type
16444 This service runs the @command{inetd} (@pxref{inetd invocation,,,
16445 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
16446 connections on internet sockets, and lazily starts the specified server
16447 program when a connection is made on one of these sockets.
16449 The value of this service is an @code{inetd-configuration} object. The
16450 following example configures the @command{inetd} daemon to provide the
16451 built-in @command{echo} service, as well as an smtp service which
16452 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
16453 gateway @code{hostname}:
16458 (inetd-configuration
16462 (socket-type 'stream)
16469 (socket-type 'stream)
16473 (program (file-append openssh "/bin/ssh"))
16475 '("ssh" "-qT" "-i" "/path/to/ssh_key"
16476 "-W" "smtp-server:25" "user@@hostname")))))))
16479 See below for more details about @code{inetd-configuration}.
16482 @deftp {Data Type} inetd-configuration
16483 Data type representing the configuration of @command{inetd}.
16486 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
16487 The @command{inetd} executable to use.
16489 @item @code{entries} (default: @code{'()})
16490 A list of @command{inetd} service entries. Each entry should be created
16491 by the @code{inetd-entry} constructor.
16495 @deftp {Data Type} inetd-entry
16496 Data type representing an entry in the @command{inetd} configuration.
16497 Each entry corresponds to a socket where @command{inetd} will listen for
16501 @item @code{node} (default: @code{#f})
16502 Optional string, a comma-separated list of local addresses
16503 @command{inetd} should use when listening for this service.
16504 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
16505 description of all options.
16507 A string, the name must correspond to an entry in @code{/etc/services}.
16508 @item @code{socket-type}
16509 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
16511 @item @code{protocol}
16512 A string, must correspond to an entry in @code{/etc/protocols}.
16513 @item @code{wait?} (default: @code{#t})
16514 Whether @command{inetd} should wait for the server to exit before
16515 listening to new service requests.
16517 A string containing the user (and, optionally, group) name of the user
16518 as whom the server should run. The group name can be specified in a
16519 suffix, separated by a colon or period, i.e.@: @code{"user"},
16520 @code{"user:group"} or @code{"user.group"}.
16521 @item @code{program} (default: @code{"internal"})
16522 The server program which will serve the requests, or @code{"internal"}
16523 if @command{inetd} should use a built-in service.
16524 @item @code{arguments} (default: @code{'()})
16525 A list strings or file-like objects, which are the server program's
16526 arguments, starting with the zeroth argument, i.e.@: the name of the
16527 program itself. For @command{inetd}'s internal services, this entry
16528 must be @code{'()} or @code{'("internal")}.
16531 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
16532 detailed discussion of each configuration field.
16536 @defvr {Scheme Variable} tor-service-type
16537 This is the type for a service that runs the @uref{https://torproject.org,
16538 Tor} anonymous networking daemon. The service is configured using a
16539 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
16540 @code{tor} unprivileged user, which is a member of the @code{tor} group.
16544 @deftp {Data Type} tor-configuration
16546 @item @code{tor} (default: @code{tor})
16547 The package that provides the Tor daemon. This package is expected to provide
16548 the daemon at @file{bin/tor} relative to its output directory. The default
16549 package is the @uref{https://www.torproject.org, Tor Project's}
16552 @item @code{config-file} (default: @code{(plain-file "empty" "")})
16553 The configuration file to use. It will be appended to a default configuration
16554 file, and the final configuration file will be passed to @code{tor} via its
16555 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
16556 file-like objects}). See @code{man tor} for details on the configuration file
16559 @item @code{hidden-services} (default: @code{'()})
16560 The list of @code{<hidden-service>} records to use. For any hidden service
16561 you include in this list, appropriate configuration to enable the hidden
16562 service will be automatically added to the default configuration file. You
16563 may conveniently create @code{<hidden-service>} records using the
16564 @code{tor-hidden-service} procedure described below.
16566 @item @code{socks-socket-type} (default: @code{'tcp})
16567 The default socket type that Tor should use for its SOCKS socket. This must
16568 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
16569 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
16570 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
16571 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
16574 If you want to customize the SOCKS socket in more detail, leave
16575 @code{socks-socket-type} at its default value of @code{'tcp} and use
16576 @code{config-file} to override the default by providing your own
16577 @code{SocksPort} option.
16581 @cindex hidden service
16582 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
16583 Define a new Tor @dfn{hidden service} called @var{name} and implementing
16584 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
16587 '((22 "127.0.0.1:22")
16588 (80 "127.0.0.1:8080"))
16591 In this example, port 22 of the hidden service is mapped to local port 22, and
16592 port 80 is mapped to local port 8080.
16594 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
16595 the @file{hostname} file contains the @code{.onion} host name for the hidden
16598 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
16599 project's documentation} for more information.
16602 The @code{(gnu services rsync)} module provides the following services:
16604 You might want an rsync daemon if you have files that you want available
16605 so anyone (or just yourself) can download existing files or upload new
16608 @deffn {Scheme Variable} rsync-service-type
16609 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
16610 The value for this service type is a
16611 @command{rsync-configuration} record as in this example:
16614 (service rsync-service-type)
16617 See below for details about @code{rsync-configuration}.
16620 @deftp {Data Type} rsync-configuration
16621 Data type representing the configuration for @code{rsync-service}.
16624 @item @code{package} (default: @var{rsync})
16625 @code{rsync} package to use.
16627 @item @code{port-number} (default: @code{873})
16628 TCP port on which @command{rsync} listens for incoming connections. If port
16629 is less than @code{1024} @command{rsync} needs to be started as the
16630 @code{root} user and group.
16632 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
16633 Name of the file where @command{rsync} writes its PID.
16635 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
16636 Name of the file where @command{rsync} writes its lock file.
16638 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
16639 Name of the file where @command{rsync} writes its log file.
16641 @item @code{use-chroot?} (default: @var{#t})
16642 Whether to use chroot for @command{rsync} shared directory.
16644 @item @code{share-path} (default: @file{/srv/rsync})
16645 Location of the @command{rsync} shared directory.
16647 @item @code{share-comment} (default: @code{"Rsync share"})
16648 Comment of the @command{rsync} shared directory.
16650 @item @code{read-only?} (default: @var{#f})
16651 Read-write permissions to shared directory.
16653 @item @code{timeout} (default: @code{300})
16654 I/O timeout in seconds.
16656 @item @code{user} (default: @var{"root"})
16657 Owner of the @code{rsync} process.
16659 @item @code{group} (default: @var{"root"})
16660 Group of the @code{rsync} process.
16662 @item @code{uid} (default: @var{"rsyncd"})
16663 User name or user ID that file transfers to and from that module should take
16664 place as when the daemon was run as @code{root}.
16666 @item @code{gid} (default: @var{"rsyncd"})
16667 Group name or group ID that will be used when accessing the module.
16672 The @code{(gnu services syncthing)} module provides the following services:
16675 You might want a syncthing daemon if you have files between two or more
16676 computers and want to sync them in real time, safely protected from
16679 @deffn {Scheme Variable} syncthing-service-type
16680 This is the service type for the @uref{https://syncthing.net/,
16681 syncthing} daemon, The value for this service type is a
16682 @command{syncthing-configuration} record as in this example:
16685 (service syncthing-service-type
16686 (syncthing-configuration (user "alice")))
16689 See below for details about @code{syncthing-configuration}.
16691 @deftp {Data Type} syncthing-configuration
16692 Data type representing the configuration for @code{syncthing-service-type}.
16695 @item @code{syncthing} (default: @var{syncthing})
16696 @code{syncthing} package to use.
16698 @item @code{arguments} (default: @var{'()})
16699 List of command-line arguments passing to @code{syncthing} binary.
16701 @item @code{logflags} (default: @var{0})
16702 Sum of loging flags, see
16703 @uref{https://docs.syncthing.net/users/syncthing.html#cmdoption-logflags, Syncthing documentation logflags}.
16705 @item @code{user} (default: @var{#f})
16706 The user as which the Syncthing service is to be run.
16707 This assumes that the specified user exists.
16709 @item @code{group} (default: @var{"users"})
16710 The group as which the Syncthing service is to be run.
16711 This assumes that the specified group exists.
16713 @item @code{home} (default: @var{#f})
16714 Common configuration and data directory. The default configuration
16715 directory is @file{$HOME} of the specified Syncthing @code{user}.
16721 Furthermore, @code{(gnu services ssh)} provides the following services.
16725 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
16726 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
16727 [#:allow-empty-passwords? #f] [#:root-login? #f] @
16728 [#:syslog-output? #t] [#:x11-forwarding? #t] @
16729 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
16730 [#:public-key-authentication? #t] [#:initialize? #t]
16731 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
16732 @var{host-key} must designate a file containing the host key, and readable
16735 When @var{daemonic?} is true, @command{lshd} will detach from the
16736 controlling terminal and log its output to syslogd, unless one sets
16737 @var{syslog-output?} to false. Obviously, it also makes lsh-service
16738 depend on existence of syslogd service. When @var{pid-file?} is true,
16739 @command{lshd} writes its PID to the file called @var{pid-file}.
16741 When @var{initialize?} is true, automatically create the seed and host key
16742 upon service activation if they do not exist yet. This may take long and
16743 require interaction.
16745 When @var{initialize?} is false, it is up to the user to initialize the
16746 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
16747 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
16748 basics,,, lsh, LSH Manual}).
16750 When @var{interfaces} is empty, lshd listens for connections on all the
16751 network interfaces; otherwise, @var{interfaces} must be a list of host names
16754 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
16755 passwords, and @var{root-login?} specifies whether to accept log-ins as
16758 The other options should be self-descriptive.
16763 @deffn {Scheme Variable} openssh-service-type
16764 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
16765 shell daemon, @command{sshd}. Its value must be an
16766 @code{openssh-configuration} record as in this example:
16769 (service openssh-service-type
16770 (openssh-configuration
16771 (x11-forwarding? #t)
16772 (permit-root-login 'without-password)
16774 `(("alice" ,(local-file "alice.pub"))
16775 ("bob" ,(local-file "bob.pub"))))))
16778 See below for details about @code{openssh-configuration}.
16780 This service can be extended with extra authorized keys, as in this
16784 (service-extension openssh-service-type
16785 (const `(("charlie"
16786 ,(local-file "charlie.pub")))))
16790 @deftp {Data Type} openssh-configuration
16791 This is the configuration record for OpenSSH's @command{sshd}.
16794 @item @code{openssh} (default @var{openssh})
16795 The Openssh package to use.
16797 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
16798 Name of the file where @command{sshd} writes its PID.
16800 @item @code{port-number} (default: @code{22})
16801 TCP port on which @command{sshd} listens for incoming connections.
16803 @item @code{permit-root-login} (default: @code{#f})
16804 This field determines whether and when to allow logins as root. If
16805 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
16806 If it's the symbol @code{'without-password}, then root logins are
16807 permitted but not with password-based authentication.
16809 @item @code{allow-empty-passwords?} (default: @code{#f})
16810 When true, users with empty passwords may log in. When false, they may
16813 @item @code{password-authentication?} (default: @code{#t})
16814 When true, users may log in with their password. When false, they have
16815 other authentication methods.
16817 @item @code{public-key-authentication?} (default: @code{#t})
16818 When true, users may log in using public key authentication. When
16819 false, users have to use other authentication method.
16821 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
16822 This is used only by protocol version 2.
16824 @item @code{x11-forwarding?} (default: @code{#f})
16825 When true, forwarding of X11 graphical client connections is
16826 enabled---in other words, @command{ssh} options @option{-X} and
16827 @option{-Y} will work.
16829 @item @code{allow-agent-forwarding?} (default: @code{#t})
16830 Whether to allow agent forwarding.
16832 @item @code{allow-tcp-forwarding?} (default: @code{#t})
16833 Whether to allow TCP forwarding.
16835 @item @code{gateway-ports?} (default: @code{#f})
16836 Whether to allow gateway ports.
16838 @item @code{challenge-response-authentication?} (default: @code{#f})
16839 Specifies whether challenge response authentication is allowed (e.g.@: via
16842 @item @code{use-pam?} (default: @code{#t})
16843 Enables the Pluggable Authentication Module interface. If set to
16844 @code{#t}, this will enable PAM authentication using
16845 @code{challenge-response-authentication?} and
16846 @code{password-authentication?}, in addition to PAM account and session
16847 module processing for all authentication types.
16849 Because PAM challenge response authentication usually serves an
16850 equivalent role to password authentication, you should disable either
16851 @code{challenge-response-authentication?} or
16852 @code{password-authentication?}.
16854 @item @code{print-last-log?} (default: @code{#t})
16855 Specifies whether @command{sshd} should print the date and time of the
16856 last user login when a user logs in interactively.
16858 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
16859 Configures external subsystems (e.g.@: file transfer daemon).
16861 This is a list of two-element lists, each of which containing the
16862 subsystem name and a command (with optional arguments) to execute upon
16865 The command @command{internal-sftp} implements an in-process SFTP
16866 server. Alternatively, one can specify the @command{sftp-server} command:
16868 (service openssh-service-type
16869 (openssh-configuration
16871 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
16874 @item @code{accepted-environment} (default: @code{'()})
16875 List of strings describing which environment variables may be exported.
16877 Each string gets on its own line. See the @code{AcceptEnv} option in
16878 @code{man sshd_config}.
16880 This example allows ssh-clients to export the @env{COLORTERM} variable.
16881 It is set by terminal emulators, which support colors. You can use it in
16882 your shell's resource file to enable colors for the prompt and commands
16883 if this variable is set.
16886 (service openssh-service-type
16887 (openssh-configuration
16888 (accepted-environment '("COLORTERM"))))
16891 @item @code{authorized-keys} (default: @code{'()})
16892 @cindex authorized keys, SSH
16893 @cindex SSH authorized keys
16894 This is the list of authorized keys. Each element of the list is a user
16895 name followed by one or more file-like objects that represent SSH public
16899 (openssh-configuration
16901 `(("rekado" ,(local-file "rekado.pub"))
16902 ("chris" ,(local-file "chris.pub"))
16903 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
16907 registers the specified public keys for user accounts @code{rekado},
16908 @code{chris}, and @code{root}.
16910 Additional authorized keys can be specified @i{via}
16911 @code{service-extension}.
16913 Note that this does @emph{not} interfere with the use of
16914 @file{~/.ssh/authorized_keys}.
16916 @item @code{log-level} (default: @code{'info})
16917 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
16918 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
16919 page for @file{sshd_config} for the full list of level names.
16921 @item @code{extra-content} (default: @code{""})
16922 This field can be used to append arbitrary text to the configuration file. It
16923 is especially useful for elaborate configurations that cannot be expressed
16924 otherwise. This configuration, for example, would generally disable root
16925 logins, but permit them from one specific IP address:
16928 (openssh-configuration
16930 Match Address 192.168.0.1
16931 PermitRootLogin yes"))
16937 @deffn {Scheme Procedure} dropbear-service [@var{config}]
16938 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
16939 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
16942 For example, to specify a Dropbear service listening on port 1234, add
16943 this call to the operating system's @code{services} field:
16946 (dropbear-service (dropbear-configuration
16947 (port-number 1234)))
16951 @deftp {Data Type} dropbear-configuration
16952 This data type represents the configuration of a Dropbear SSH daemon.
16955 @item @code{dropbear} (default: @var{dropbear})
16956 The Dropbear package to use.
16958 @item @code{port-number} (default: 22)
16959 The TCP port where the daemon waits for incoming connections.
16961 @item @code{syslog-output?} (default: @code{#t})
16962 Whether to enable syslog output.
16964 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
16965 File name of the daemon's PID file.
16967 @item @code{root-login?} (default: @code{#f})
16968 Whether to allow @code{root} logins.
16970 @item @code{allow-empty-passwords?} (default: @code{#f})
16971 Whether to allow empty passwords.
16973 @item @code{password-authentication?} (default: @code{#t})
16974 Whether to enable password-based authentication.
16979 @deffn {Scheme Variable} autossh-service-type
16980 This is the type for the @uref{https://www.harding.motd.ca/autossh,
16981 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
16982 restarting it as necessary should it die or stop passing traffic.
16983 AutoSSH can be run manually from the command-line by passing arguments
16984 to the binary @command{autossh} from the package @code{autossh}, but it
16985 can also be run as a Guix service. This latter use case is documented
16988 AutoSSH can be used to forward local traffic to a remote machine using
16989 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
16992 For example, to specify a service running autossh as the user
16993 @code{pino} and forwarding all local connections to port @code{8081} to
16994 @code{remote:8081} using an SSH tunnel, add this call to the operating
16995 system's @code{services} field:
16998 (service autossh-service-type
16999 (autossh-configuration
17001 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
17005 @deftp {Data Type} autossh-configuration
17006 This data type represents the configuration of an AutoSSH service.
17010 @item @code{user} (default @code{"autossh"})
17011 The user as which the AutoSSH service is to be run.
17012 This assumes that the specified user exists.
17014 @item @code{poll} (default @code{600})
17015 Specifies the connection poll time in seconds.
17017 @item @code{first-poll} (default @code{#f})
17018 Specifies how many seconds AutoSSH waits before the first connection
17019 test. After this first test, polling is resumed at the pace defined in
17020 @code{poll}. When set to @code{#f}, the first poll is not treated
17021 specially and will also use the connection poll specified in
17024 @item @code{gate-time} (default @code{30})
17025 Specifies how many seconds an SSH connection must be active before it is
17026 considered successful.
17028 @item @code{log-level} (default @code{1})
17029 The log level, corresponding to the levels used by syslog---so @code{0}
17030 is the most silent while @code{7} is the chattiest.
17032 @item @code{max-start} (default @code{#f})
17033 The maximum number of times SSH may be (re)started before AutoSSH exits.
17034 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
17036 @item @code{message} (default @code{""})
17037 The message to append to the echo message sent when testing connections.
17039 @item @code{port} (default @code{"0"})
17040 The ports used for monitoring the connection. When set to @code{"0"},
17041 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
17042 a positive integer, ports @var{n} and @var{n}+1 are used for
17043 monitoring the connection, such that port @var{n} is the base
17044 monitoring port and @code{n+1} is the echo port. When set to
17045 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
17046 integers, the ports @var{n} and @var{m} are used for monitoring the
17047 connection, such that port @var{n} is the base monitoring port and
17048 @var{m} is the echo port.
17050 @item @code{ssh-options} (default @code{'()})
17051 The list of command-line arguments to pass to @command{ssh} when it is
17052 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
17053 may cause undefined behaviour.
17059 @deffn {Scheme Variable} webssh-service-type
17060 This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
17061 program that runs a web SSH client. WebSSH can be run manually from the
17062 command-line by passing arguments to the binary @command{wssh} from the
17063 package @code{webssh}, but it can also be run as a Guix service. This
17064 latter use case is documented here.
17066 For example, to specify a service running WebSSH on loopback interface
17067 on port @code{8888} with reject policy with a list of allowed to
17068 connection hosts, and NGINX as a reverse-proxy to this service listening
17069 for HTTPS connection, add this call to the operating system's
17070 @code{services} field:
17073 (service webssh-service-type
17074 (webssh-configuration (address "127.0.0.1")
17077 (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
17078 "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
17080 (service nginx-service-type
17081 (nginx-configuration
17084 (nginx-server-configuration
17085 (inherit %webssh-configuration-nginx)
17086 (server-name '("webssh.example.com"))
17087 (listen '("443 ssl"))
17088 (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
17089 (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
17091 (cons (nginx-location-configuration
17092 (uri "/.well-known")
17093 (body '("root /var/www;")))
17094 (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
17098 @deftp {Data Type} webssh-configuration
17099 Data type representing the configuration for @code{webssh-service}.
17102 @item @code{package} (default: @var{webssh})
17103 @code{webssh} package to use.
17105 @item @code{user-name} (default: @var{"webssh"})
17106 User name or user ID that file transfers to and from that module should take
17109 @item @code{group-name} (default: @var{"webssh"})
17110 Group name or group ID that will be used when accessing the module.
17112 @item @code{address} (default: @var{#f})
17113 IP address on which @command{webssh} listens for incoming connections.
17115 @item @code{port} (default: @var{8888})
17116 TCP port on which @command{webssh} listens for incoming connections.
17118 @item @code{policy} (default: @var{#f})
17119 Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
17121 @item @code{known-hosts} (default: @var{'()})
17122 List of hosts which allowed for SSH connection from @command{webssh}.
17124 @item @code{log-file} (default: @file{"/var/log/webssh.log"})
17125 Name of the file where @command{webssh} writes its log file.
17127 @item @code{log-level} (default: @var{#f})
17133 @defvr {Scheme Variable} %facebook-host-aliases
17134 This variable contains a string for use in @file{/etc/hosts}
17135 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
17136 line contains a entry that maps a known server name of the Facebook
17137 on-line service---e.g., @code{www.facebook.com}---to the local
17138 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
17140 This variable is typically used in the @code{hosts-file} field of an
17141 @code{operating-system} declaration (@pxref{operating-system Reference,
17142 @file{/etc/hosts}}):
17145 (use-modules (gnu) (guix))
17148 (host-name "mymachine")
17151 ;; Create a /etc/hosts file with aliases for "localhost"
17152 ;; and "mymachine", as well as for Facebook servers.
17153 (plain-file "hosts"
17154 (string-append (local-host-aliases host-name)
17155 %facebook-host-aliases))))
17158 This mechanism can prevent programs running locally, such as Web
17159 browsers, from accessing Facebook.
17162 The @code{(gnu services avahi)} provides the following definition.
17164 @defvr {Scheme Variable} avahi-service-type
17165 This is the service that runs @command{avahi-daemon}, a system-wide
17166 mDNS/DNS-SD responder that allows for service discovery and
17167 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
17168 Its value must be an @code{avahi-configuration} record---see below.
17170 This service extends the name service cache daemon (nscd) so that it can
17171 resolve @code{.local} host names using
17172 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
17173 Service Switch}, for information on host name resolution.
17175 Additionally, add the @var{avahi} package to the system profile so that
17176 commands such as @command{avahi-browse} are directly usable.
17179 @deftp {Data Type} avahi-configuration
17180 Data type representation the configuration for Avahi.
17184 @item @code{host-name} (default: @code{#f})
17185 If different from @code{#f}, use that as the host name to
17186 publish for this machine; otherwise, use the machine's actual host name.
17188 @item @code{publish?} (default: @code{#t})
17189 When true, allow host names and services to be published (broadcast) over the
17192 @item @code{publish-workstation?} (default: @code{#t})
17193 When true, @command{avahi-daemon} publishes the machine's host name and IP
17194 address via mDNS on the local network. To view the host names published on
17195 your local network, you can run:
17198 avahi-browse _workstation._tcp
17201 @item @code{wide-area?} (default: @code{#f})
17202 When true, DNS-SD over unicast DNS is enabled.
17204 @item @code{ipv4?} (default: @code{#t})
17205 @itemx @code{ipv6?} (default: @code{#t})
17206 These fields determine whether to use IPv4/IPv6 sockets.
17208 @item @code{domains-to-browse} (default: @code{'()})
17209 This is a list of domains to browse.
17213 @deffn {Scheme Variable} openvswitch-service-type
17214 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
17215 service, whose value should be an @code{openvswitch-configuration}
17219 @deftp {Data Type} openvswitch-configuration
17220 Data type representing the configuration of Open vSwitch, a multilayer
17221 virtual switch which is designed to enable massive network automation
17222 through programmatic extension.
17225 @item @code{package} (default: @var{openvswitch})
17226 Package object of the Open vSwitch.
17231 @defvr {Scheme Variable} pagekite-service-type
17232 This is the service type for the @uref{https://pagekite.net, PageKite} service,
17233 a tunneling solution for making localhost servers publicly visible, even from
17234 behind restrictive firewalls or NAT without forwarded ports. The value for
17235 this service type is a @code{pagekite-configuration} record.
17237 Here's an example exposing the local HTTP and SSH daemons:
17240 (service pagekite-service-type
17241 (pagekite-configuration
17242 (kites '("http:@@kitename:localhost:80:@@kitesecret"
17243 "raw/22:@@kitename:localhost:22:@@kitesecret"))
17244 (extra-file "/etc/pagekite.rc")))
17248 @deftp {Data Type} pagekite-configuration
17249 Data type representing the configuration of PageKite.
17252 @item @code{package} (default: @var{pagekite})
17253 Package object of PageKite.
17255 @item @code{kitename} (default: @code{#f})
17256 PageKite name for authenticating to the frontend server.
17258 @item @code{kitesecret} (default: @code{#f})
17259 Shared secret for authenticating to the frontend server. You should probably
17260 put this inside @code{extra-file} instead.
17262 @item @code{frontend} (default: @code{#f})
17263 Connect to the named PageKite frontend server instead of the
17264 @uref{https://pagekite.net,,pagekite.net} service.
17266 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
17267 List of service kites to use. Exposes HTTP on port 80 by default. The format
17268 is @code{proto:kitename:host:port:secret}.
17270 @item @code{extra-file} (default: @code{#f})
17271 Extra configuration file to read, which you are expected to create manually.
17272 Use this to add additional options and manage shared secrets out-of-band.
17277 @defvr {Scheme Variable} yggdrasil-service-type
17278 The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
17279 Yggdrasil network}, an early-stage implementation of a fully end-to-end
17280 encrypted IPv6 network.
17283 Yggdrasil provides name-independent routing with cryptographically generated
17284 addresses. Static addressing means you can keep the same address as long as
17285 you want, even if you move to a new location, or generate a new address (by
17286 generating new keys) whenever you want.
17287 @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
17290 Pass it a value of @code{yggdrasil-configuration} to connect it to public
17291 peers and/or local peers.
17293 Here is an example using public peers and a static address. The static
17294 signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
17295 (the default value for @code{config-file}).
17298 ;; part of the operating-system declaration
17299 (service yggdrasil-service-type
17300 (yggdrasil-configuration
17301 (autoconf? #f) ;; use only the public peers
17304 ;; https://github.com/yggdrasil-network/public-peers
17305 '((peers . #("tcp://1.2.3.4:1337"))))
17306 ;; /etc/yggdrasil-private.conf is the default value for config-file
17310 # sample content for /etc/yggdrasil-private.conf
17312 # Your public encryption key. Your peers may ask you for this to put
17313 # into their AllowedEncryptionPublicKeys configuration.
17314 EncryptionPublicKey: 378dc5...
17316 # Your private encryption key. DO NOT share this with anyone!
17317 EncryptionPrivateKey: 0777...
17319 # Your public signing key. You should not ordinarily need to share
17320 # this with anyone.
17321 SigningPublicKey: e1664...
17323 # Your private signing key. DO NOT share this with anyone!
17324 SigningPrivateKey: 0589d...
17329 @deftp {Data Type} yggdrasil-configuration
17330 Data type representing the configuration of Yggdrasil.
17333 @item @code{package} (default: @code{yggdrasil})
17334 Package object of Yggdrasil.
17336 @item @code{json-config} (default: @code{'()})
17337 Contents of @file{/etc/yggdrasil.conf}. Will be merged with
17338 @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
17339 the Guix store, which is readable to all users. @strong{Do not store your
17340 private keys in it}. See the output of @code{yggdrasil -genconf} for a
17341 quick overview of valid keys and their default values.
17343 @item @code{autoconf?} (default: @code{#f})
17344 Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
17345 and peer with IPv6 neighbors.
17347 @item @code{log-level} (default: @code{'info})
17348 How much detail to include in logs. Use @code{'debug} for more detail.
17350 @item @code{log-to} (default: @code{'stdout})
17351 Where to send logs. By default, the service logs standard output to
17352 @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
17353 sends output to the running syslog service.
17355 @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
17356 What HJSON file to load sensitive data from. This is where private keys
17357 should be stored, which are necessary to specify if you don't want a
17358 randomized address after each restart. Use @code{#f} to disable. Options
17359 defined in this file take precedence over @code{json-config}. Use the output
17360 of @code{yggdrasil -genconf} as a starting point. To configure a static
17361 address, delete everything except these options:
17364 @item @code{EncryptionPublicKey}
17365 @item @code{EncryptionPrivateKey}
17366 @item @code{SigningPublicKey}
17367 @item @code{SigningPrivateKey}
17373 @deffn {Scheme Variable} keepalived-service-type
17374 This is the type for the @uref{https://www.keepalived.org/, Keepalived}
17375 routing software, @command{keepalived}. Its value must be an
17376 @code{keepalived-configuration} record as in this example for master
17380 (service keepalived-service-type
17381 (keepalived-configuration
17382 (config-file (local-file "keepalived-master.conf"))))
17385 where @file{keepalived-master.conf}:
17388 vrrp_instance my-group @{
17391 virtual_router_id 100
17393 unicast_peer @{ 10.0.0.2 @}
17394 virtual_ipaddress @{
17400 and for backup machine:
17403 (service keepalived-service-type
17404 (keepalived-configuration
17405 (config-file (local-file "keepalived-backup.conf"))))
17408 where @file{keepalived-backup.conf}:
17411 vrrp_instance my-group @{
17414 virtual_router_id 100
17416 unicast_peer @{ 10.0.0.3 @}
17417 virtual_ipaddress @{
17424 @node Unattended Upgrades
17425 @subsection Unattended Upgrades
17427 @cindex unattended upgrades
17428 @cindex upgrades, unattended
17429 Guix provides a service to perform @emph{unattended upgrades}:
17430 periodically, the system automatically reconfigures itself from the
17431 latest Guix. Guix System has several properties that make unattended
17436 upgrades are transactional (either the upgrade succeeds or it fails, but
17437 you cannot end up with an ``in-between'' system state);
17439 the upgrade log is kept---you can view it with @command{guix system
17440 list-generations}---and you can roll back to any previous generation,
17441 should the upgraded system fail to behave as intended;
17443 channel code is authenticated so you know you can only run genuine code
17444 (@pxref{Channels});
17446 @command{guix system reconfigure} prevents downgrades, which makes it
17447 immune to @dfn{downgrade attacks}.
17450 To set up unattended upgrades, add an instance of
17451 @code{unattended-upgrade-service-type} like the one below to the list of
17452 your operating system services:
17455 (service unattended-upgrade-service-type)
17458 The defaults above set up weekly upgrades: every Sunday at midnight.
17459 You do not need to provide the operating system configuration file: it
17460 uses @file{/run/current-system/configuration.scm}, which ensures it
17461 always uses your latest configuration---@pxref{provenance-service-type},
17462 for more information about this file.
17464 There are several things that can be configured, in particular the
17465 periodicity and services (daemons) to be restarted upon completion.
17466 When the upgrade is successful, the service takes care of deleting
17467 system generations older that some threshold, as per @command{guix
17468 system delete-generations}. See the reference below for details.
17470 To ensure that upgrades are actually happening, you can run
17471 @command{guix system describe}. To investigate upgrade failures, visit
17472 the unattended upgrade log file (see below).
17474 @defvr {Scheme Variable} unattended-upgrade-service-type
17475 This is the service type for unattended upgrades. It sets up an mcron
17476 job (@pxref{Scheduled Job Execution}) that runs @command{guix system
17477 reconfigure} from the latest version of the specified channels.
17479 Its value must be a @code{unattended-upgrade-configuration} record (see
17483 @deftp {Data Type} unattended-upgrade-configuration
17484 This data type represents the configuration of the unattended upgrade
17485 service. The following fields are available:
17488 @item @code{schedule} (default: @code{"30 01 * * 0"})
17489 This is the schedule of upgrades, expressed as a gexp containing an
17490 mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
17491 mcron, GNU@tie{}mcron}).
17493 @item @code{channels} (default: @code{#~%default-channels})
17494 This gexp specifies the channels to use for the upgrade
17495 (@pxref{Channels}). By default, the tip of the official @code{guix}
17498 @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
17499 This field specifies the operating system configuration file to use.
17500 The default is to reuse the config file of the current configuration.
17502 There are cases, though, where referring to
17503 @file{/run/current-system/configuration.scm} is not enough, for instance
17504 because that file refers to extra files (SSH public keys, extra
17505 configuration files, etc.) @i{via} @code{local-file} and similar
17506 constructs. For those cases, we recommend something along these lines:
17509 (unattended-upgrade-configuration
17510 (operating-system-file
17511 (file-append (local-file "." "config-dir" #:recursive? #t)
17515 The effect here is to import all of the current directory into the
17516 store, and to refer to @file{config.scm} within that directory.
17517 Therefore, uses of @code{local-file} within @file{config.scm} will work
17518 as expected. @xref{G-Expressions}, for information about
17519 @code{local-file} and @code{file-append}.
17521 @item @code{services-to-restart} (default: @code{'(mcron)})
17522 This field specifies the Shepherd services to restart when the upgrade
17525 Those services are restarted right away upon completion, as with
17526 @command{herd restart}, which ensures that the latest version is
17527 running---remember that by default @command{guix system reconfigure}
17528 only restarts services that are not currently running, which is
17529 conservative: it minimizes disruption but leaves outdated services
17532 Use @command{herd status} to find out candidates for restarting.
17533 @xref{Services}, for general information about services. Common
17534 services to restart would include @code{ntpd} and @code{ssh-daemon}.
17536 By default, the @code{mcron} service is restarted. This ensures that
17537 the latest version of the unattended upgrade job will be used next time.
17539 @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
17540 This is the expiration time in seconds for system generations. System
17541 generations older that this amount of time are deleted with
17542 @command{guix system delete-generations} when an upgrade completes.
17545 The unattended upgrade service does not run the garbage collector. You
17546 will probably want to set up your own mcron job to run @command{guix gc}
17550 @item @code{maximum-duration} (default: @code{3600})
17551 Maximum duration in seconds for the upgrade; past that time, the upgrade
17554 This is primarily useful to ensure the upgrade does not end up
17555 rebuilding or re-downloading ``the world''.
17557 @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
17558 File where unattended upgrades are logged.
17563 @subsection X Window
17566 @cindex X Window System
17567 @cindex login manager
17568 Support for the X Window graphical display system---specifically
17569 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
17570 there is no @code{xorg-service} procedure. Instead, the X server is
17571 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
17574 @cindex GNOME, login manager
17575 GDM of course allows users to log in into window managers and desktop
17576 environments other than GNOME; for those using GNOME, GDM is required for
17577 features such as automatic screen locking.
17579 @cindex window manager
17580 To use X11, you must install at least one @dfn{window manager}---for
17581 example the @code{windowmaker} or @code{openbox} packages---preferably
17582 by adding it to the @code{packages} field of your operating system
17583 definition (@pxref{operating-system Reference, system-wide packages}).
17585 @defvr {Scheme Variable} gdm-service-type
17586 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
17587 Desktop Manager} (GDM), a program that manages graphical display servers and
17588 handles graphical user logins. Its value must be a @code{gdm-configuration}
17591 @cindex session types (X11)
17592 @cindex X11 session types
17593 GDM looks for @dfn{session types} described by the @file{.desktop} files in
17594 @file{/run/current-system/profile/share/xsessions} and allows users to choose
17595 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
17596 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
17597 set of packages automatically makes them available at the log-in screen.
17599 In addition, @file{~/.xsession} files are honored. When available,
17600 @file{~/.xsession} must be an executable that starts a window manager
17601 and/or other X clients.
17604 @deftp {Data Type} gdm-configuration
17606 @item @code{auto-login?} (default: @code{#f})
17607 @itemx @code{default-user} (default: @code{#f})
17608 When @code{auto-login?} is false, GDM presents a log-in screen.
17610 When @code{auto-login?} is true, GDM logs in directly as
17611 @code{default-user}.
17613 @item @code{debug?} (default: @code{#f})
17614 When true, GDM writes debug messages to its log.
17616 @item @code{gnome-shell-assets} (default: ...)
17617 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
17619 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
17620 Configuration of the Xorg graphical server.
17622 @item @code{xsession} (default: @code{(xinitrc)})
17623 Script to run before starting a X session.
17625 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
17626 File name of the @code{dbus-daemon} executable.
17628 @item @code{gdm} (default: @code{gdm})
17629 The GDM package to use.
17633 @defvr {Scheme Variable} slim-service-type
17634 This is the type for the SLiM graphical login manager for X11.
17636 Like GDM, SLiM looks for session types described by @file{.desktop} files and
17637 allows users to choose a session from the log-in screen using @kbd{F1}. It
17638 also honors @file{~/.xsession} files.
17640 Unlike GDM, SLiM does not spawn the user session on a different VT after
17641 logging in, which means that you can only start one graphical session. If you
17642 want to be able to run multiple graphical sessions at the same time you have
17643 to add multiple SLiM services to your system services. The following example
17644 shows how to replace the default GDM service with two SLiM services on tty7
17648 (use-modules (gnu services)
17649 (gnu services desktop)
17650 (gnu services xorg)
17651 (srfi srfi-1)) ;for 'remove'
17655 (services (cons* (service slim-service-type (slim-configuration
17658 (service slim-service-type (slim-configuration
17661 (remove (lambda (service)
17662 (eq? (service-kind service) gdm-service-type))
17663 %desktop-services))))
17668 @deftp {Data Type} slim-configuration
17669 Data type representing the configuration of @code{slim-service-type}.
17672 @item @code{allow-empty-passwords?} (default: @code{#t})
17673 Whether to allow logins with empty passwords.
17675 @item @code{auto-login?} (default: @code{#f})
17676 @itemx @code{default-user} (default: @code{""})
17677 When @code{auto-login?} is false, SLiM presents a log-in screen.
17679 When @code{auto-login?} is true, SLiM logs in directly as
17680 @code{default-user}.
17682 @item @code{theme} (default: @code{%default-slim-theme})
17683 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
17684 The graphical theme to use and its name.
17686 @item @code{auto-login-session} (default: @code{#f})
17687 If true, this must be the name of the executable to start as the default
17688 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
17690 If false, a session described by one of the available @file{.desktop}
17691 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
17695 You must install at least one window manager in the system profile or in
17696 your user profile. Failing to do that, if @code{auto-login-session} is
17697 false, you will be unable to log in.
17700 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
17701 Configuration of the Xorg graphical server.
17703 @item @code{display} (default @code{":0"})
17704 The display on which to start the Xorg graphical server.
17706 @item @code{vt} (default @code{"vt7"})
17707 The VT on which to start the Xorg graphical server.
17709 @item @code{xauth} (default: @code{xauth})
17710 The XAuth package to use.
17712 @item @code{shepherd} (default: @code{shepherd})
17713 The Shepherd package used when invoking @command{halt} and
17716 @item @code{sessreg} (default: @code{sessreg})
17717 The sessreg package used in order to register the session.
17719 @item @code{slim} (default: @code{slim})
17720 The SLiM package to use.
17724 @defvr {Scheme Variable} %default-theme
17725 @defvrx {Scheme Variable} %default-theme-name
17726 The default SLiM theme and its name.
17730 @deftp {Data Type} sddm-configuration
17731 This is the data type representing the SDDM service configuration.
17734 @item @code{display-server} (default: "x11")
17735 Select display server to use for the greeter. Valid values are
17736 @samp{"x11"} or @samp{"wayland"}.
17738 @item @code{numlock} (default: "on")
17739 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
17741 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
17742 Command to run when halting.
17744 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
17745 Command to run when rebooting.
17747 @item @code{theme} (default "maldives")
17748 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
17749 @samp{"maldives"} or @samp{"maya"}.
17751 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
17752 Directory to look for themes.
17754 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
17755 Directory to look for faces.
17757 @item @code{default-path} (default "/run/current-system/profile/bin")
17758 Default PATH to use.
17760 @item @code{minimum-uid} (default: 1000)
17761 Minimum UID displayed in SDDM and allowed for log-in.
17763 @item @code{maximum-uid} (default: 2000)
17764 Maximum UID to display in SDDM.
17766 @item @code{remember-last-user?} (default #t)
17767 Remember last user.
17769 @item @code{remember-last-session?} (default #t)
17770 Remember last session.
17772 @item @code{hide-users} (default "")
17773 Usernames to hide from SDDM greeter.
17775 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
17776 Users with shells listed will be hidden from the SDDM greeter.
17778 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
17779 Script to run before starting a wayland session.
17781 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
17782 Directory to look for desktop files starting wayland sessions.
17784 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
17785 Configuration of the Xorg graphical server.
17787 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
17790 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
17793 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
17794 Script to run after starting xorg-server.
17796 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
17797 Script to run before stopping xorg-server.
17799 @item @code{xsession-command} (default: @code{xinitrc})
17800 Script to run before starting a X session.
17802 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
17803 Directory to look for desktop files starting X sessions.
17805 @item @code{minimum-vt} (default: 7)
17808 @item @code{auto-login-user} (default "")
17809 User to use for auto-login.
17811 @item @code{auto-login-session} (default "")
17812 Desktop file to use for auto-login.
17814 @item @code{relogin?} (default #f)
17815 Relogin after logout.
17820 @cindex login manager
17822 @defvr {Scheme Variable} sddm-service-type
17823 This is the type of the service to run the
17824 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
17825 must be a @code{sddm-configuration} record (see below).
17827 Here's an example use:
17830 (service sddm-service-type
17831 (sddm-configuration
17832 (auto-login-user "alice")
17833 (auto-login-session "xfce.desktop")))
17837 @deftp {Data Type} sddm-configuration
17838 This data type represents the configuration of the SDDM login manager.
17839 The available fields are:
17842 @item @code{sddm} (default: @code{sddm})
17843 The SDDM package to use.
17845 @item @code{display-server} (default: @code{"x11"})
17846 This must be either @code{"x11"} or @code{"wayland"}.
17848 @c FIXME: Add more fields.
17850 @item @code{auto-login-user} (default: @code{""})
17851 If non-empty, this is the user account under which to log in
17854 @item @code{auto-login-session} (default: @code{""})
17855 If non-empty, this is the @file{.desktop} file name to use as the
17856 auto-login session.
17860 @cindex Xorg, configuration
17861 @deftp {Data Type} xorg-configuration
17862 This data type represents the configuration of the Xorg graphical display
17863 server. Note that there is no Xorg service; instead, the X server is started
17864 by a ``display manager'' such as GDM, SDDM, and SLiM@. Thus, the configuration
17865 of these display managers aggregates an @code{xorg-configuration} record.
17868 @item @code{modules} (default: @code{%default-xorg-modules})
17869 This is a list of @dfn{module packages} loaded by the Xorg
17870 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
17872 @item @code{fonts} (default: @code{%default-xorg-fonts})
17873 This is a list of font directories to add to the server's @dfn{font path}.
17875 @item @code{drivers} (default: @code{'()})
17876 This must be either the empty list, in which case Xorg chooses a graphics
17877 driver automatically, or a list of driver names that will be tried in this
17878 order---e.g., @code{("modesetting" "vesa")}.
17880 @item @code{resolutions} (default: @code{'()})
17881 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
17882 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
17885 @cindex keyboard layout, for Xorg
17886 @cindex keymap, for Xorg
17887 @item @code{keyboard-layout} (default: @code{#f})
17888 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
17889 English (``qwerty'') for a 105-key PC keyboard.
17891 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
17892 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
17893 information on how to specify the keyboard layout.
17895 @item @code{extra-config} (default: @code{'()})
17896 This is a list of strings or objects appended to the configuration file. It
17897 is used to pass extra text to be added verbatim to the configuration file.
17899 @item @code{server} (default: @code{xorg-server})
17900 This is the package providing the Xorg server.
17902 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
17903 This is the list of command-line arguments to pass to the X server. The
17904 default is @code{-nolisten tcp}.
17908 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
17909 [@var{login-manager-service-type}]
17910 Tell the log-in manager (of type @var{login-manager-service-type}) to use
17911 @var{config}, an @code{<xorg-configuration>} record.
17913 Since the Xorg configuration is embedded in the log-in manager's
17914 configuration---e.g., @code{gdm-configuration}---this procedure provides a
17915 shorthand to set the Xorg configuration.
17918 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
17919 Return a @code{startx} script in which the modules, fonts, etc. specified
17920 in @var{config}, are available. The result should be used in place of
17923 Usually the X server is started by a login manager.
17927 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
17928 Add @var{package}, a package for a screen locker or screen saver whose
17929 command is @var{program}, to the set of setuid programs and add a PAM entry
17930 for it. For example:
17933 (screen-locker-service xlockmore "xlock")
17936 makes the good ol' XlockMore usable.
17940 @node Printing Services
17941 @subsection Printing Services
17943 @cindex printer support with CUPS
17944 The @code{(gnu services cups)} module provides a Guix service definition
17945 for the CUPS printing service. To add printer support to a Guix
17946 system, add a @code{cups-service} to the operating system definition:
17948 @deffn {Scheme Variable} cups-service-type
17949 The service type for the CUPS print server. Its value should be a valid
17950 CUPS configuration (see below). To use the default settings, simply
17953 (service cups-service-type)
17957 The CUPS configuration controls the basic things about your CUPS
17958 installation: what interfaces it listens on, what to do if a print job
17959 fails, how much logging to do, and so on. To actually add a printer,
17960 you have to visit the @url{http://localhost:631} URL, or use a tool such
17961 as GNOME's printer configuration services. By default, configuring a
17962 CUPS service will generate a self-signed certificate if needed, for
17963 secure connections to the print server.
17965 Suppose you want to enable the Web interface of CUPS and also add
17966 support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
17967 package and for HP printers @i{via} the @code{hplip-minimal} package.
17968 You can do that directly, like this (you need to use the
17969 @code{(gnu packages cups)} module):
17972 (service cups-service-type
17973 (cups-configuration
17974 (web-interface? #t)
17976 (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
17979 Note: If you wish to use the Qt5 based GUI which comes with the hplip
17980 package then it is suggested that you install the @code{hplip} package,
17981 either in your OS configuration file or as your user.
17983 The available configuration parameters follow. Each parameter
17984 definition is preceded by its type; for example, @samp{string-list foo}
17985 indicates that the @code{foo} parameter should be specified as a list of
17986 strings. There is also a way to specify the configuration as a string,
17987 if you have an old @code{cupsd.conf} file that you want to port over
17988 from some other system; see the end for more details.
17990 @c The following documentation was initially generated by
17991 @c (generate-documentation) in (gnu services cups). Manually maintained
17992 @c documentation is better, so we shouldn't hesitate to edit below as
17993 @c needed. However if the change you want to make to this documentation
17994 @c can be done in an automated way, it's probably easier to change
17995 @c (generate-documentation) than to make it below and have to deal with
17996 @c the churn as CUPS updates.
17999 Available @code{cups-configuration} fields are:
18001 @deftypevr {@code{cups-configuration} parameter} package cups
18005 @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list brlaser cups-filters epson-inkjet-printer-escpr foomatic-filters hplip-minimal splix)})
18006 Drivers and other extensions to the CUPS package.
18009 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
18010 Configuration of where to write logs, what directories to use for print
18011 spools, and related privileged configuration parameters.
18013 Available @code{files-configuration} fields are:
18015 @deftypevr {@code{files-configuration} parameter} log-location access-log
18016 Defines the access log filename. Specifying a blank filename disables
18017 access log generation. The value @code{stderr} causes log entries to be
18018 sent to the standard error file when the scheduler is running in the
18019 foreground, or to the system log daemon when run in the background. The
18020 value @code{syslog} causes log entries to be sent to the system log
18021 daemon. The server name may be included in filenames using the string
18022 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
18024 Defaults to @samp{"/var/log/cups/access_log"}.
18027 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
18028 Where CUPS should cache data.
18030 Defaults to @samp{"/var/cache/cups"}.
18033 @deftypevr {@code{files-configuration} parameter} string config-file-perm
18034 Specifies the permissions for all configuration files that the scheduler
18037 Note that the permissions for the printers.conf file are currently
18038 masked to only allow access from the scheduler user (typically root).
18039 This is done because printer device URIs sometimes contain sensitive
18040 authentication information that should not be generally known on the
18041 system. There is no way to disable this security feature.
18043 Defaults to @samp{"0640"}.
18046 @deftypevr {@code{files-configuration} parameter} log-location error-log
18047 Defines the error log filename. Specifying a blank filename disables
18048 error log generation. The value @code{stderr} causes log entries to be
18049 sent to the standard error file when the scheduler is running in the
18050 foreground, or to the system log daemon when run in the background. The
18051 value @code{syslog} causes log entries to be sent to the system log
18052 daemon. The server name may be included in filenames using the string
18053 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
18055 Defaults to @samp{"/var/log/cups/error_log"}.
18058 @deftypevr {@code{files-configuration} parameter} string fatal-errors
18059 Specifies which errors are fatal, causing the scheduler to exit. The
18064 No errors are fatal.
18067 All of the errors below are fatal.
18070 Browsing initialization errors are fatal, for example failed connections
18071 to the DNS-SD daemon.
18074 Configuration file syntax errors are fatal.
18077 Listen or Port errors are fatal, except for IPv6 failures on the
18078 loopback or @code{any} addresses.
18081 Log file creation or write errors are fatal.
18084 Bad startup file permissions are fatal, for example shared TLS
18085 certificate and key files with world-read permissions.
18088 Defaults to @samp{"all -browse"}.
18091 @deftypevr {@code{files-configuration} parameter} boolean file-device?
18092 Specifies whether the file pseudo-device can be used for new printer
18093 queues. The URI @uref{file:///dev/null} is always allowed.
18095 Defaults to @samp{#f}.
18098 @deftypevr {@code{files-configuration} parameter} string group
18099 Specifies the group name or ID that will be used when executing external
18102 Defaults to @samp{"lp"}.
18105 @deftypevr {@code{files-configuration} parameter} string log-file-perm
18106 Specifies the permissions for all log files that the scheduler writes.
18108 Defaults to @samp{"0644"}.
18111 @deftypevr {@code{files-configuration} parameter} log-location page-log
18112 Defines the page log filename. Specifying a blank filename disables
18113 page log generation. The value @code{stderr} causes log entries to be
18114 sent to the standard error file when the scheduler is running in the
18115 foreground, or to the system log daemon when run in the background. The
18116 value @code{syslog} causes log entries to be sent to the system log
18117 daemon. The server name may be included in filenames using the string
18118 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
18120 Defaults to @samp{"/var/log/cups/page_log"}.
18123 @deftypevr {@code{files-configuration} parameter} string remote-root
18124 Specifies the username that is associated with unauthenticated accesses
18125 by clients claiming to be the root user. The default is @code{remroot}.
18127 Defaults to @samp{"remroot"}.
18130 @deftypevr {@code{files-configuration} parameter} file-name request-root
18131 Specifies the directory that contains print jobs and other HTTP request
18134 Defaults to @samp{"/var/spool/cups"}.
18137 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
18138 Specifies the level of security sandboxing that is applied to print
18139 filters, backends, and other child processes of the scheduler; either
18140 @code{relaxed} or @code{strict}. This directive is currently only
18141 used/supported on macOS.
18143 Defaults to @samp{strict}.
18146 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
18147 Specifies the location of TLS certificates and private keys. CUPS will
18148 look for public and private keys in this directory: @file{.crt} files
18149 for PEM-encoded certificates and corresponding @file{.key} files for
18150 PEM-encoded private keys.
18152 Defaults to @samp{"/etc/cups/ssl"}.
18155 @deftypevr {@code{files-configuration} parameter} file-name server-root
18156 Specifies the directory containing the server configuration files.
18158 Defaults to @samp{"/etc/cups"}.
18161 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
18162 Specifies whether the scheduler calls fsync(2) after writing
18163 configuration or state files.
18165 Defaults to @samp{#f}.
18168 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
18169 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
18172 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
18173 Specifies the directory where temporary files are stored.
18175 Defaults to @samp{"/var/spool/cups/tmp"}.
18178 @deftypevr {@code{files-configuration} parameter} string user
18179 Specifies the user name or ID that is used when running external
18182 Defaults to @samp{"lp"}.
18185 @deftypevr {@code{files-configuration} parameter} string set-env
18186 Set the specified environment variable to be passed to child processes.
18188 Defaults to @samp{"variable value"}.
18192 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
18193 Specifies the logging level for the AccessLog file. The @code{config}
18194 level logs when printers and classes are added, deleted, or modified and
18195 when configuration files are accessed or updated. The @code{actions}
18196 level logs when print jobs are submitted, held, released, modified, or
18197 canceled, and any of the conditions for @code{config}. The @code{all}
18198 level logs all requests.
18200 Defaults to @samp{actions}.
18203 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
18204 Specifies whether to purge job history data automatically when it is no
18205 longer required for quotas.
18207 Defaults to @samp{#f}.
18210 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
18211 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
18212 For example, @samp{"_cups" "_print"} will tell network clients that both
18213 CUPS sharing and IPP Everywhere are supported.
18215 Defaults to @samp{"_cups"}.
18218 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
18219 Specifies which protocols to use for local printer sharing.
18221 Defaults to @samp{dnssd}.
18224 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
18225 Specifies whether the CUPS web interface is advertised.
18227 Defaults to @samp{#f}.
18230 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
18231 Specifies whether shared printers are advertised.
18233 Defaults to @samp{#f}.
18236 @deftypevr {@code{cups-configuration} parameter} string classification
18237 Specifies the security classification of the server. Any valid banner
18238 name can be used, including @samp{"classified"}, @samp{"confidential"},
18239 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
18240 banner can be omitted to disable secure printing functions.
18242 Defaults to @samp{""}.
18245 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
18246 Specifies whether users may override the classification (cover page) of
18247 individual print jobs using the @code{job-sheets} option.
18249 Defaults to @samp{#f}.
18252 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
18253 Specifies the default type of authentication to use.
18255 Defaults to @samp{Basic}.
18258 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
18259 Specifies whether encryption will be used for authenticated requests.
18261 Defaults to @samp{Required}.
18264 @deftypevr {@code{cups-configuration} parameter} string default-language
18265 Specifies the default language to use for text and web content.
18267 Defaults to @samp{"en"}.
18270 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
18271 Specifies the default paper size for new print queues. @samp{"Auto"}
18272 uses a locale-specific default, while @samp{"None"} specifies there is
18273 no default paper size. Specific size names are typically
18274 @samp{"Letter"} or @samp{"A4"}.
18276 Defaults to @samp{"Auto"}.
18279 @deftypevr {@code{cups-configuration} parameter} string default-policy
18280 Specifies the default access policy to use.
18282 Defaults to @samp{"default"}.
18285 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
18286 Specifies whether local printers are shared by default.
18288 Defaults to @samp{#t}.
18291 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
18292 Specifies the delay for updating of configuration and state files, in
18293 seconds. A value of 0 causes the update to happen as soon as possible,
18294 typically within a few milliseconds.
18296 Defaults to @samp{30}.
18299 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
18300 Specifies what to do when an error occurs. Possible values are
18301 @code{abort-job}, which will discard the failed print job;
18302 @code{retry-job}, which will retry the job at a later time;
18303 @code{retry-current-job}, which retries the failed job immediately; and
18304 @code{stop-printer}, which stops the printer.
18306 Defaults to @samp{stop-printer}.
18309 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
18310 Specifies the maximum cost of filters that are run concurrently, which
18311 can be used to minimize disk, memory, and CPU resource problems. A
18312 limit of 0 disables filter limiting. An average print to a
18313 non-PostScript printer needs a filter limit of about 200. A PostScript
18314 printer needs about half that (100). Setting the limit below these
18315 thresholds will effectively limit the scheduler to printing a single job
18318 Defaults to @samp{0}.
18321 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
18322 Specifies the scheduling priority of filters that are run to print a
18323 job. The nice value ranges from 0, the highest priority, to 19, the
18326 Defaults to @samp{0}.
18329 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
18330 Specifies whether to do reverse lookups on connecting clients. The
18331 @code{double} setting causes @code{cupsd} to verify that the hostname
18332 resolved from the address matches one of the addresses returned for that
18333 hostname. Double lookups also prevent clients with unregistered
18334 addresses from connecting to your server. Only set this option to
18335 @code{#t} or @code{double} if absolutely required.
18337 Defaults to @samp{#f}.
18340 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
18341 Specifies the number of seconds to wait before killing the filters and
18342 backend associated with a canceled or held job.
18344 Defaults to @samp{30}.
18347 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
18348 Specifies the interval between retries of jobs in seconds. This is
18349 typically used for fax queues but can also be used with normal print
18350 queues whose error policy is @code{retry-job} or
18351 @code{retry-current-job}.
18353 Defaults to @samp{30}.
18356 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
18357 Specifies the number of retries that are done for jobs. This is
18358 typically used for fax queues but can also be used with normal print
18359 queues whose error policy is @code{retry-job} or
18360 @code{retry-current-job}.
18362 Defaults to @samp{5}.
18365 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
18366 Specifies whether to support HTTP keep-alive connections.
18368 Defaults to @samp{#t}.
18371 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
18372 Specifies how long an idle client connection remains open, in seconds.
18374 Defaults to @samp{30}.
18377 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
18378 Specifies the maximum size of print files, IPP requests, and HTML form
18379 data. A limit of 0 disables the limit check.
18381 Defaults to @samp{0}.
18384 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
18385 Listens on the specified interfaces for connections. Valid values are
18386 of the form @var{address}:@var{port}, where @var{address} is either an
18387 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
18388 indicate all addresses. Values can also be file names of local UNIX
18389 domain sockets. The Listen directive is similar to the Port directive
18390 but allows you to restrict access to specific interfaces or networks.
18393 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
18394 Specifies the number of pending connections that will be allowed. This
18395 normally only affects very busy servers that have reached the MaxClients
18396 limit, but can also be triggered by large numbers of simultaneous
18397 connections. When the limit is reached, the operating system will
18398 refuse additional connections until the scheduler can accept the pending
18401 Defaults to @samp{128}.
18404 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
18405 Specifies a set of additional access controls.
18407 Available @code{location-access-controls} fields are:
18409 @deftypevr {@code{location-access-controls} parameter} file-name path
18410 Specifies the URI path to which the access control applies.
18413 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
18414 Access controls for all access to this path, in the same format as the
18415 @code{access-controls} of @code{operation-access-control}.
18417 Defaults to @samp{()}.
18420 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
18421 Access controls for method-specific access to this path.
18423 Defaults to @samp{()}.
18425 Available @code{method-access-controls} fields are:
18427 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
18428 If @code{#t}, apply access controls to all methods except the listed
18429 methods. Otherwise apply to only the listed methods.
18431 Defaults to @samp{#f}.
18434 @deftypevr {@code{method-access-controls} parameter} method-list methods
18435 Methods to which this access control applies.
18437 Defaults to @samp{()}.
18440 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
18441 Access control directives, as a list of strings. Each string should be
18442 one directive, such as @samp{"Order allow,deny"}.
18444 Defaults to @samp{()}.
18449 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
18450 Specifies the number of debugging messages that are retained for logging
18451 if an error occurs in a print job. Debug messages are logged regardless
18452 of the LogLevel setting.
18454 Defaults to @samp{100}.
18457 @deftypevr {@code{cups-configuration} parameter} log-level log-level
18458 Specifies the level of logging for the ErrorLog file. The value
18459 @code{none} stops all logging while @code{debug2} logs everything.
18461 Defaults to @samp{info}.
18464 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
18465 Specifies the format of the date and time in the log files. The value
18466 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
18468 Defaults to @samp{standard}.
18471 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
18472 Specifies the maximum number of simultaneous clients that are allowed by
18475 Defaults to @samp{100}.
18478 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
18479 Specifies the maximum number of simultaneous clients that are allowed
18480 from a single address.
18482 Defaults to @samp{100}.
18485 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
18486 Specifies the maximum number of copies that a user can print of each
18489 Defaults to @samp{9999}.
18492 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
18493 Specifies the maximum time a job may remain in the @code{indefinite}
18494 hold state before it is canceled. A value of 0 disables cancellation of
18497 Defaults to @samp{0}.
18500 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
18501 Specifies the maximum number of simultaneous jobs that are allowed. Set
18502 to 0 to allow an unlimited number of jobs.
18504 Defaults to @samp{500}.
18507 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
18508 Specifies the maximum number of simultaneous jobs that are allowed per
18509 printer. A value of 0 allows up to MaxJobs jobs per printer.
18511 Defaults to @samp{0}.
18514 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
18515 Specifies the maximum number of simultaneous jobs that are allowed per
18516 user. A value of 0 allows up to MaxJobs jobs per user.
18518 Defaults to @samp{0}.
18521 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
18522 Specifies the maximum time a job may take to print before it is
18523 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
18525 Defaults to @samp{10800}.
18528 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
18529 Specifies the maximum size of the log files before they are rotated, in
18530 bytes. The value 0 disables log rotation.
18532 Defaults to @samp{1048576}.
18535 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
18536 Specifies the maximum amount of time to allow between files in a
18537 multiple file print job, in seconds.
18539 Defaults to @samp{300}.
18542 @deftypevr {@code{cups-configuration} parameter} string page-log-format
18543 Specifies the format of PageLog lines. Sequences beginning with percent
18544 (@samp{%}) characters are replaced with the corresponding information,
18545 while all other characters are copied literally. The following percent
18546 sequences are recognized:
18550 insert a single percent character
18553 insert the value of the specified IPP attribute
18556 insert the number of copies for the current page
18559 insert the current page number
18562 insert the current date and time in common log format
18568 insert the printer name
18571 insert the username
18574 A value of the empty string disables page logging. The string @code{%p
18575 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
18576 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
18579 Defaults to @samp{""}.
18582 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
18583 Passes the specified environment variable(s) to child processes; a list
18586 Defaults to @samp{()}.
18589 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
18590 Specifies named access control policies.
18592 Available @code{policy-configuration} fields are:
18594 @deftypevr {@code{policy-configuration} parameter} string name
18595 Name of the policy.
18598 @deftypevr {@code{policy-configuration} parameter} string job-private-access
18599 Specifies an access list for a job's private values. @code{@@ACL} maps
18600 to the printer's requesting-user-name-allowed or
18601 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
18602 owner. @code{@@SYSTEM} maps to the groups listed for the
18603 @code{system-group} field of the @code{files-config} configuration,
18604 which is reified into the @code{cups-files.conf(5)} file. Other
18605 possible elements of the access list include specific user names, and
18606 @code{@@@var{group}} to indicate members of a specific group. The
18607 access list may also be simply @code{all} or @code{default}.
18609 Defaults to @samp{"@@OWNER @@SYSTEM"}.
18612 @deftypevr {@code{policy-configuration} parameter} string job-private-values
18613 Specifies the list of job values to make private, or @code{all},
18614 @code{default}, or @code{none}.
18616 Defaults to @samp{"job-name job-originating-host-name
18617 job-originating-user-name phone"}.
18620 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
18621 Specifies an access list for a subscription's private values.
18622 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
18623 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
18624 owner. @code{@@SYSTEM} maps to the groups listed for the
18625 @code{system-group} field of the @code{files-config} configuration,
18626 which is reified into the @code{cups-files.conf(5)} file. Other
18627 possible elements of the access list include specific user names, and
18628 @code{@@@var{group}} to indicate members of a specific group. The
18629 access list may also be simply @code{all} or @code{default}.
18631 Defaults to @samp{"@@OWNER @@SYSTEM"}.
18634 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
18635 Specifies the list of job values to make private, or @code{all},
18636 @code{default}, or @code{none}.
18638 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
18639 notify-subscriber-user-name notify-user-data"}.
18642 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
18643 Access control by IPP operation.
18645 Defaults to @samp{()}.
18649 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
18650 Specifies whether job files (documents) are preserved after a job is
18651 printed. If a numeric value is specified, job files are preserved for
18652 the indicated number of seconds after printing. Otherwise a boolean
18653 value applies indefinitely.
18655 Defaults to @samp{86400}.
18658 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
18659 Specifies whether the job history is preserved after a job is printed.
18660 If a numeric value is specified, the job history is preserved for the
18661 indicated number of seconds after printing. If @code{#t}, the job
18662 history is preserved until the MaxJobs limit is reached.
18664 Defaults to @samp{#t}.
18667 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
18668 Specifies the amount of time to wait for job completion before
18669 restarting the scheduler.
18671 Defaults to @samp{30}.
18674 @deftypevr {@code{cups-configuration} parameter} string rip-cache
18675 Specifies the maximum amount of memory to use when converting documents
18676 into bitmaps for a printer.
18678 Defaults to @samp{"128m"}.
18681 @deftypevr {@code{cups-configuration} parameter} string server-admin
18682 Specifies the email address of the server administrator.
18684 Defaults to @samp{"root@@localhost.localdomain"}.
18687 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
18688 The ServerAlias directive is used for HTTP Host header validation when
18689 clients connect to the scheduler from external interfaces. Using the
18690 special name @code{*} can expose your system to known browser-based DNS
18691 rebinding attacks, even when accessing sites through a firewall. If the
18692 auto-discovery of alternate names does not work, we recommend listing
18693 each alternate name with a ServerAlias directive instead of using
18696 Defaults to @samp{*}.
18699 @deftypevr {@code{cups-configuration} parameter} string server-name
18700 Specifies the fully-qualified host name of the server.
18702 Defaults to @samp{"localhost"}.
18705 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
18706 Specifies what information is included in the Server header of HTTP
18707 responses. @code{None} disables the Server header. @code{ProductOnly}
18708 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
18709 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
18710 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
18711 the output of the @code{uname} command. @code{Full} reports @code{CUPS
18712 2.0.0 (@var{uname}) IPP/2.0}.
18714 Defaults to @samp{Minimal}.
18717 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
18718 Listens on the specified interfaces for encrypted connections. Valid
18719 values are of the form @var{address}:@var{port}, where @var{address} is
18720 either an IPv6 address enclosed in brackets, an IPv4 address, or
18721 @code{*} to indicate all addresses.
18723 Defaults to @samp{()}.
18726 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
18727 Sets encryption options. By default, CUPS only supports encryption
18728 using TLS v1.0 or higher using known secure cipher suites. Security is
18729 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
18730 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
18731 suites, which are required for some older clients. The @code{AllowSSL3} option
18732 enables SSL v3.0, which is required for some older clients that do not support
18733 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
18734 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
18735 protocol version to TLS v1.1.
18737 Defaults to @samp{()}.
18740 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
18741 Specifies whether the scheduler requires clients to strictly adhere to
18742 the IPP specifications.
18744 Defaults to @samp{#f}.
18747 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
18748 Specifies the HTTP request timeout, in seconds.
18750 Defaults to @samp{300}.
18754 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
18755 Specifies whether the web interface is enabled.
18757 Defaults to @samp{#f}.
18760 At this point you're probably thinking ``oh dear, Guix manual, I like
18761 you but you can stop already with the configuration options''. Indeed.
18762 However, one more point: it could be that you have an existing
18763 @code{cupsd.conf} that you want to use. In that case, you can pass an
18764 @code{opaque-cups-configuration} as the configuration of a
18765 @code{cups-service-type}.
18767 Available @code{opaque-cups-configuration} fields are:
18769 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
18773 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
18774 The contents of the @code{cupsd.conf}, as a string.
18777 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
18778 The contents of the @code{cups-files.conf} file, as a string.
18781 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
18782 strings of the same name, you could instantiate a CUPS service like
18786 (service cups-service-type
18787 (opaque-cups-configuration
18788 (cupsd.conf cupsd.conf)
18789 (cups-files.conf cups-files.conf)))
18793 @node Desktop Services
18794 @subsection Desktop Services
18796 The @code{(gnu services desktop)} module provides services that are
18797 usually useful in the context of a ``desktop'' setup---that is, on a
18798 machine running a graphical display server, possibly with graphical user
18799 interfaces, etc. It also defines services that provide specific desktop
18800 environments like GNOME, Xfce or MATE.
18802 To simplify things, the module defines a variable containing the set of
18803 services that users typically expect on a machine with a graphical
18804 environment and networking:
18806 @defvr {Scheme Variable} %desktop-services
18807 This is a list of services that builds upon @code{%base-services} and
18808 adds or adjusts services for a typical ``desktop'' setup.
18810 In particular, it adds a graphical login manager (@pxref{X Window,
18811 @code{gdm-service-type}}), screen lockers, a network management tool
18812 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
18813 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
18814 energy and color management services, the @code{elogind} login and seat
18815 manager, the Polkit privilege service, the GeoClue location service, the
18816 AccountsService daemon that allows authorized users change system passwords,
18817 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
18818 name service switch service configured to be able to use @code{nss-mdns}
18819 (@pxref{Name Service Switch, mDNS}).
18822 The @code{%desktop-services} variable can be used as the @code{services}
18823 field of an @code{operating-system} declaration (@pxref{operating-system
18824 Reference, @code{services}}).
18826 Additionally, the @code{gnome-desktop-service-type},
18827 @code{xfce-desktop-service}, @code{mate-desktop-service-type},
18828 @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
18829 procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
18830 ``add GNOME'' means that system-level services like the backlight adjustment
18831 helpers and the power management utilities are added to the system, extending
18832 @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
18833 elevated privileges on a limited number of special-purpose system interfaces.
18834 Additionally, adding a service made by @code{gnome-desktop-service-type} adds
18835 the GNOME metapackage to the system profile. Likewise, adding the Xfce
18836 service not only adds the @code{xfce} metapackage to the system profile, but
18837 it also gives the Thunar file manager the ability to open a ``root-mode'' file
18838 management window, if the user authenticates using the administrator's
18839 password via the standard polkit graphical interface. To ``add MATE'' means
18840 that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
18841 to operate with elevated privileges on a limited number of special-purpose
18842 system interfaces. Additionally, adding a service of type
18843 @code{mate-desktop-service-type} adds the MATE metapackage to the system
18844 profile. ``Adding Enlightenment'' means that @code{dbus} is extended
18845 appropriately, and several of Enlightenment's binaries are set as setuid,
18846 allowing Enlightenment's screen locker and other functionality to work as
18849 The desktop environments in Guix use the Xorg display server by
18850 default. If you'd like to use the newer display server protocol
18851 called Wayland, you need to use the @code{sddm-service} instead of
18852 GDM as the graphical login manager. You should then
18853 select the ``GNOME (Wayland)'' session in SDDM@. Alternatively you can
18854 also try starting GNOME on Wayland manually from a TTY with the
18855 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
18856 gnome-session``. Currently only GNOME has support for Wayland.
18858 @defvr {Scheme Variable} gnome-desktop-service-type
18859 This is the type of the service that adds the @uref{https://www.gnome.org,
18860 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
18861 object (see below).
18863 This service adds the @code{gnome} package to the system profile, and extends
18864 polkit with the actions from @code{gnome-settings-daemon}.
18867 @deftp {Data Type} gnome-desktop-configuration
18868 Configuration record for the GNOME desktop environment.
18871 @item @code{gnome} (default: @code{gnome})
18872 The GNOME package to use.
18876 @defvr {Scheme Variable} xfce-desktop-service-type
18877 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
18878 desktop environment. Its value is an @code{xfce-desktop-configuration} object
18881 This service adds the @code{xfce} package to the system profile, and
18882 extends polkit with the ability for @code{thunar} to manipulate the file
18883 system as root from within a user session, after the user has authenticated
18884 with the administrator's password.
18886 Note that @code{xfce4-panel} and its plugin packages should be installed in
18887 the same profile to ensure compatibility. When using this service, you should
18888 add extra plugins (@code{xfce4-whiskermenu-plugin},
18889 @code{xfce4-weather-plugin}, etc.) to the @code{packages} field of your
18890 @code{operating-system}.
18893 @deftp {Data Type} xfce-desktop-configuration
18894 Configuration record for the Xfce desktop environment.
18897 @item @code{xfce} (default: @code{xfce})
18898 The Xfce package to use.
18902 @deffn {Scheme Variable} mate-desktop-service-type
18903 This is the type of the service that runs the @uref{https://mate-desktop.org/,
18904 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
18905 object (see below).
18907 This service adds the @code{mate} package to the system
18908 profile, and extends polkit with the actions from
18909 @code{mate-settings-daemon}.
18912 @deftp {Data Type} mate-desktop-configuration
18913 Configuration record for the MATE desktop environment.
18916 @item @code{mate} (default: @code{mate})
18917 The MATE package to use.
18921 @deffn {Scheme Variable} lxqt-desktop-service-type
18922 This is the type of the service that runs the @uref{https://lxqt.github.io,
18923 LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
18924 object (see below).
18926 This service adds the @code{lxqt} package to the system
18930 @deftp {Data Type} lxqt-desktop-configuration
18931 Configuration record for the LXQt desktop environment.
18934 @item @code{lxqt} (default: @code{lxqt})
18935 The LXQT package to use.
18939 @deffn {Scheme Variable} enlightenment-desktop-service-type
18940 Return a service that adds the @code{enlightenment} package to the system
18941 profile, and extends dbus with actions from @code{efl}.
18944 @deftp {Data Type} enlightenment-desktop-service-configuration
18946 @item @code{enlightenment} (default: @code{enlightenment})
18947 The enlightenment package to use.
18951 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
18952 the default @code{%desktop-services} variable doesn't include any of
18953 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
18954 @code{%desktop-services} in the @code{services} field of your
18955 @code{operating-system}:
18958 (use-modules (gnu))
18959 (use-service-modules desktop)
18962 ;; cons* adds items to the list given as its last argument.
18963 (services (cons* (service gnome-desktop-service-type)
18964 (service xfce-desktop-service)
18965 %desktop-services))
18969 These desktop environments will then be available as options in the
18970 graphical login window.
18972 The actual service definitions included in @code{%desktop-services} and
18973 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
18974 are described below.
18976 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
18977 Return a service that runs the ``system bus'', using @var{dbus}, with
18978 support for @var{services}.
18980 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
18981 facility. Its system bus is used to allow system services to communicate
18982 and to be notified of system-wide events.
18984 @var{services} must be a list of packages that provide an
18985 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
18986 and policy files. For example, to allow avahi-daemon to use the system bus,
18987 @var{services} must be equal to @code{(list avahi)}.
18990 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
18991 Return a service that runs the @code{elogind} login and
18992 seat management daemon. @uref{https://github.com/elogind/elogind,
18993 Elogind} exposes a D-Bus interface that can be used to know which users
18994 are logged in, know what kind of sessions they have open, suspend the
18995 system, inhibit system suspend, reboot the system, and other tasks.
18997 Elogind handles most system-level power events for a computer, for
18998 example suspending the system when a lid is closed, or shutting it down
18999 when the power button is pressed.
19001 The @var{config} keyword argument specifies the configuration for
19002 elogind, and should be the result of an @code{(elogind-configuration
19003 (@var{parameter} @var{value})...)} invocation. Available parameters and
19004 their default values are:
19007 @item kill-user-processes?
19009 @item kill-only-users
19011 @item kill-exclude-users
19013 @item inhibit-delay-max-seconds
19015 @item handle-power-key
19017 @item handle-suspend-key
19019 @item handle-hibernate-key
19021 @item handle-lid-switch
19023 @item handle-lid-switch-docked
19025 @item handle-lid-switch-external-power
19027 @item power-key-ignore-inhibited?
19029 @item suspend-key-ignore-inhibited?
19031 @item hibernate-key-ignore-inhibited?
19033 @item lid-switch-ignore-inhibited?
19035 @item holdoff-timeout-seconds
19039 @item idle-action-seconds
19041 @item runtime-directory-size-percent
19043 @item runtime-directory-size
19047 @item suspend-state
19048 @code{("mem" "standby" "freeze")}
19051 @item hibernate-state
19053 @item hibernate-mode
19054 @code{("platform" "shutdown")}
19055 @item hybrid-sleep-state
19057 @item hybrid-sleep-mode
19058 @code{("suspend" "platform" "shutdown")}
19062 @deffn {Scheme Procedure} accountsservice-service @
19063 [#:accountsservice @var{accountsservice}]
19064 Return a service that runs AccountsService, a system service that can
19065 list available accounts, change their passwords, and so on.
19066 AccountsService integrates with PolicyKit to enable unprivileged users
19067 to acquire the capability to modify their system configuration.
19068 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
19069 accountsservice web site} for more information.
19071 The @var{accountsservice} keyword argument is the @code{accountsservice}
19072 package to expose as a service.
19075 @deffn {Scheme Procedure} polkit-service @
19076 [#:polkit @var{polkit}]
19077 Return a service that runs the
19078 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
19079 management service}, which allows system administrators to grant access to
19080 privileged operations in a structured way. By querying the Polkit service, a
19081 privileged system component can know when it should grant additional
19082 capabilities to ordinary users. For example, an ordinary user can be granted
19083 the capability to suspend the system if the user is logged in locally.
19086 @defvr {Scheme Variable} polkit-wheel-service
19087 Service that adds the @code{wheel} group as admins to the Polkit
19088 service. This makes it so that users in the @code{wheel} group are queried
19089 for their own passwords when performing administrative actions instead of
19090 @code{root}'s, similar to the behaviour used by @code{sudo}.
19093 @defvr {Scheme Variable} upower-service-type
19094 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
19095 system-wide monitor for power consumption and battery levels, with the given
19096 configuration settings.
19098 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
19099 notably used by GNOME.
19102 @deftp {Data Type} upower-configuration
19103 Data type representation the configuration for UPower.
19107 @item @code{upower} (default: @var{upower})
19108 Package to use for @code{upower}.
19110 @item @code{watts-up-pro?} (default: @code{#f})
19111 Enable the Watts Up Pro device.
19113 @item @code{poll-batteries?} (default: @code{#t})
19114 Enable polling the kernel for battery level changes.
19116 @item @code{ignore-lid?} (default: @code{#f})
19117 Ignore the lid state, this can be useful if it's incorrect on a device.
19119 @item @code{use-percentage-for-policy?} (default: @code{#f})
19120 Whether battery percentage based policy should be used. The default is to use
19121 the time left, change to @code{#t} to use the percentage.
19123 @item @code{percentage-low} (default: @code{10})
19124 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
19125 at which the battery is considered low.
19127 @item @code{percentage-critical} (default: @code{3})
19128 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
19129 at which the battery is considered critical.
19131 @item @code{percentage-action} (default: @code{2})
19132 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
19133 at which action will be taken.
19135 @item @code{time-low} (default: @code{1200})
19136 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
19137 seconds at which the battery is considered low.
19139 @item @code{time-critical} (default: @code{300})
19140 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
19141 seconds at which the battery is considered critical.
19143 @item @code{time-action} (default: @code{120})
19144 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
19145 seconds at which action will be taken.
19147 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
19148 The action taken when @code{percentage-action} or @code{time-action} is
19149 reached (depending on the configuration of @code{use-percentage-for-policy?}).
19151 Possible values are:
19161 @code{'hybrid-sleep}.
19167 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
19168 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
19169 UDisks}, a @dfn{disk management} daemon that provides user interfaces
19170 with notifications and ways to mount/unmount disks. Programs that talk
19171 to UDisks include the @command{udisksctl} command, part of UDisks, and
19172 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
19173 it will only be able to use the file-system utilities installed in the
19174 system profile. For example if you want to be able to mount NTFS
19175 file-systems in read and write fashion, you'll need to have
19176 @code{ntfs-3g} installed system-wide.
19179 @deffn {Scheme Variable} colord-service-type
19180 This is the type of the service that runs @command{colord}, a system
19181 service with a D-Bus
19182 interface to manage the color profiles of input and output devices such as
19183 screens and scanners. It is notably used by the GNOME Color Manager graphical
19184 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
19185 site} for more information.
19188 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
19189 Return a configuration allowing an application to access GeoClue
19190 location data. @var{name} is the Desktop ID of the application, without
19191 the @code{.desktop} part. If @var{allowed?} is true, the application
19192 will have access to location information by default. The boolean
19193 @var{system?} value indicates whether an application is a system component
19194 or not. Finally @var{users} is a list of UIDs of all users for which
19195 this application is allowed location info access. An empty users list
19196 means that all users are allowed.
19199 @cindex scanner access
19200 @deffn {Scheme Procedure} sane-service-type
19201 This service provides access to scanners @i{via}
19202 @uref{http://www.sane-project.org, SANE} by installing the necessary udev
19206 @defvr {Scheme Variable} %standard-geoclue-applications
19207 The standard list of well-known GeoClue application configurations,
19208 granting authority to the GNOME date-and-time utility to ask for the
19209 current location in order to set the time zone, and allowing the
19210 IceCat and Epiphany web browsers to request location information.
19211 IceCat and Epiphany both query the user before allowing a web page to
19212 know the user's location.
19215 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
19216 [#:whitelist '()] @
19217 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
19218 [#:submit-data? #f]
19219 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
19220 [#:submission-nick "geoclue"] @
19221 [#:applications %standard-geoclue-applications]
19222 Return a service that runs the GeoClue location service. This service
19223 provides a D-Bus interface to allow applications to request access to a
19224 user's physical location, and optionally to add information to online
19225 location databases. See
19226 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
19227 web site} for more information.
19230 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
19231 [@w{#:auto-enable? #f}]
19232 Return a service that runs the @command{bluetoothd} daemon, which
19233 manages all the Bluetooth devices and provides a number of D-Bus
19234 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
19235 powered automatically at boot, which can be useful when using a
19236 bluetooth keyboard or mouse.
19238 Users need to be in the @code{lp} group to access the D-Bus service.
19241 @defvr {Scheme Variable} gnome-keyring-service-type
19242 This is the type of the service that adds the
19243 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
19244 value is a @code{gnome-keyring-configuration} object (see below).
19246 This service adds the @code{gnome-keyring} package to the system profile
19247 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
19248 a user's login keyring when they log in or setting its password with passwd.
19251 @deftp {Data Type} gnome-keyring-configuration
19252 Configuration record for the GNOME Keyring service.
19255 @item @code{keyring} (default: @code{gnome-keyring})
19256 The GNOME keyring package to use.
19258 @item @code{pam-services}
19259 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
19260 services to extend, where @var{service} is the name of an existing
19261 service to extend and @var{kind} is one of @code{login} or
19264 If @code{login} is given, it adds an optional
19265 @code{pam_gnome_keyring.so} to the auth block without arguments and to
19266 the session block with @code{auto_start}. If @code{passwd} is given, it
19267 adds an optional @code{pam_gnome_keyring.so} to the password block
19270 By default, this field contains ``gdm-password'' with the value @code{login}
19271 and ``passwd'' is with the value @code{passwd}.
19276 @node Sound Services
19277 @subsection Sound Services
19279 @cindex sound support
19281 @cindex PulseAudio, sound support
19283 The @code{(gnu services sound)} module provides a service to configure the
19284 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
19285 preferred ALSA output driver.
19287 @deffn {Scheme Variable} alsa-service-type
19288 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
19289 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
19290 configuration file. The value for this type is a @command{alsa-configuration}
19291 record as in this example:
19294 (service alsa-service-type)
19297 See below for details about @code{alsa-configuration}.
19300 @deftp {Data Type} alsa-configuration
19301 Data type representing the configuration for @code{alsa-service}.
19304 @item @code{alsa-plugins} (default: @var{alsa-plugins})
19305 @code{alsa-plugins} package to use.
19307 @item @code{pulseaudio?} (default: @var{#t})
19308 Whether ALSA applications should transparently be made to use the
19309 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
19311 Using PulseAudio allows you to run several sound-producing applications
19312 at the same time and to individual control them @i{via}
19313 @command{pavucontrol}, among other things.
19315 @item @code{extra-options} (default: @var{""})
19316 String to append to the @file{/etc/asound.conf} file.
19321 Individual users who want to override the system configuration of ALSA can do
19322 it with the @file{~/.asoundrc} file:
19325 # In guix, we have to specify the absolute path for plugins.
19327 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
19330 # Routing ALSA to jack:
19331 # <http://jackaudio.org/faq/routing_alsa.html>.
19335 0 system:playback_1
19336 1 system:playback_2
19353 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
19356 @deffn {Scheme Variable} pulseaudio-service-type
19357 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
19358 sound server. It exists to allow system overrides of the default settings
19359 via @code{pulseaudio-configuration}, see below.
19362 This service overrides per-user configuration files. If you want
19363 PulseAudio to honor configuration files in @file{~/.config/pulse} you
19364 have to unset the environment variables @env{PULSE_CONFIG} and
19365 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
19369 This service on its own does not ensure, that the @code{pulseaudio} package
19370 exists on your machine. It merely adds configuration files for it, as
19371 detailed below. In the (admittedly unlikely) case, that you find yourself
19372 without a @code{pulseaudio} package, consider enabling it through the
19373 @code{alsa-service-type} above.
19377 @deftp {Data Type} pulseaudio-configuration
19378 Data type representing the configuration for @code{pulseaudio-service}.
19381 @item @code{client-conf} (default: @code{'()})
19382 List of settings to set in @file{client.conf}.
19383 Accepts a list of strings or a symbol-value pairs. A string will be
19384 inserted as-is with a newline added. A pair will be formatted as
19385 ``key = value'', again with a newline added.
19387 @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
19388 List of settings to set in @file{daemon.conf}, formatted just like
19391 @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
19392 Script file to use as @file{default.pa}.
19394 @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
19395 Script file to use as @file{system.pa}.
19399 @deffn {Scheme Variable} ladspa-service-type
19400 This service sets the @var{LADSPA_PATH} variable, so that programs, which
19401 respect it, e.g. PulseAudio, can load LADSPA plugins.
19403 The following example will setup the service to enable modules from the
19404 @code{swh-plugins} package:
19407 (service ladspa-service-type
19408 (ladspa-configuration (plugins (list swh-plugins))))
19411 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
19416 @node Database Services
19417 @subsection Database Services
19421 The @code{(gnu services databases)} module provides the following services.
19423 @subsubheading PostgreSQL
19425 The following example describes a PostgreSQL service with the default
19429 (service postgresql-service-type
19430 (postgresql-configuration
19431 (postgresql postgresql-10)))
19434 If the services fails to start, it may be due to an incompatible
19435 cluster already present in @var{data-directory}. Adjust it (or, if you
19436 don't need the cluster anymore, delete @var{data-directory}), then
19437 restart the service.
19439 Peer authentication is used by default and the @code{postgres} user
19440 account has no shell, which prevents the direct execution of @code{psql}
19441 commands as this user. To use @code{psql}, you can temporarily log in
19442 as @code{postgres} using a shell, create a PostgreSQL superuser with the
19443 same name as one of the system users and then create the associated
19447 sudo -u postgres -s /bin/sh
19448 createuser --interactive
19449 createdb $MY_USER_LOGIN # Replace appropriately.
19452 @deftp {Data Type} postgresql-configuration
19453 Data type representing the configuration for the
19454 @code{postgresql-service-type}.
19457 @item @code{postgresql}
19458 PostgreSQL package to use for the service.
19460 @item @code{port} (default: @code{5432})
19461 Port on which PostgreSQL should listen.
19463 @item @code{locale} (default: @code{"en_US.utf8"})
19464 Locale to use as the default when creating the database cluster.
19466 @item @code{config-file} (default: @code{(postgresql-config-file)})
19467 The configuration file to use when running PostgreSQL@. The default
19468 behaviour uses the postgresql-config-file record with the default values
19471 @item @code{log-directory} (default: @code{"/var/log/postgresql"})
19472 The directory where @command{pg_ctl} output will be written in a file
19473 named @code{"pg_ctl.log"}. This file can be useful to debug PostgreSQL
19474 configuration errors for instance.
19476 @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
19477 Directory in which to store the data.
19479 @item @code{extension-packages} (default: @code{'()})
19480 @cindex postgresql extension-packages
19481 Additional extensions are loaded from packages listed in
19482 @var{extension-packages}. Extensions are available at runtime. For instance,
19483 to create a geographic database using the @code{postgis} extension, a user can
19484 configure the postgresql-service as in this example:
19488 (use-package-modules databases geo)
19492 ;; postgresql is required to run `psql' but postgis is not required for
19493 ;; proper operation.
19494 (packages (cons* postgresql %base-packages))
19497 (service postgresql-service-type
19498 (postgresql-configuration
19499 (postgresql postgresql-10)
19500 (extension-packages (list postgis))))
19504 Then the extension becomes visible and you can initialise an empty geographic
19505 database in this way:
19509 > create database postgistest;
19510 > \connect postgistest;
19511 > create extension postgis;
19512 > create extension postgis_topology;
19515 There is no need to add this field for contrib extensions such as hstore or
19516 dblink as they are already loadable by postgresql. This field is only
19517 required to add extensions provided by other packages.
19522 @deftp {Data Type} postgresql-config-file
19523 Data type representing the PostgreSQL configuration file. As shown in
19524 the following example, this can be used to customize the configuration
19525 of PostgreSQL@. Note that you can use any G-expression or filename in
19526 place of this record, if you already have a configuration file you'd
19527 like to use for example.
19530 (service postgresql-service-type
19531 (postgresql-configuration
19533 (postgresql-config-file
19534 (log-destination "stderr")
19536 (plain-file "pg_hba.conf"
19538 local all all trust
19539 host all all 127.0.0.1/32 md5
19540 host all all ::1/128 md5"))
19542 '(("session_preload_libraries" "auto_explain")
19543 ("random_page_cost" 2)
19544 ("auto_explain.log_min_duration" "100 ms")
19545 ("work_mem" "500 MB")
19546 ("logging_collector" #t)
19547 ("log_directory" "/var/log/postgresql")))))))
19551 @item @code{log-destination} (default: @code{"syslog"})
19552 The logging method to use for PostgreSQL@. Multiple values are accepted,
19553 separated by commas.
19555 @item @code{hba-file} (default: @code{%default-postgres-hba})
19556 Filename or G-expression for the host-based authentication
19559 @item @code{ident-file} (default: @code{%default-postgres-ident})
19560 Filename or G-expression for the user name mapping configuration.
19562 @item @code{socket-directory} (default: @code{"/var/run/postgresql"})
19563 Specifies the directory of the Unix-domain socket(s) on which PostgreSQL
19564 is to listen for connections from client applications. If set to
19565 @code{#false} PostgreSQL does not listen on any Unix-domain sockets, in
19566 which case only TCP/IP sockets can be used to connect to the server.
19568 @item @code{extra-config} (default: @code{'()})
19569 List of additional keys and values to include in the PostgreSQL config
19570 file. Each entry in the list should be a list where the first element
19571 is the key, and the remaining elements are the values.
19573 The values can be numbers, booleans or strings and will be mapped to
19574 PostgreSQL parameters types @code{Boolean}, @code{String},
19575 @code{Numeric}, @code{Numeric with Unit} and @code{Enumerated} described
19576 @uref{https://www.postgresql.org/docs/current/config-setting.html,
19582 @deffn {Scheme Variable} postgresql-role-service-type
19583 This service allows to create PostgreSQL roles and databases after
19584 PostgreSQL service start. Here is an example of its use.
19587 (service postgresql-role-service-type
19588 (postgresql-role-configuration
19590 (list (postgresql-role
19592 (create-database? #t))))))
19595 This service can be extended with extra roles, as in this
19599 (service-extension postgresql-role-service-type
19600 (const (postgresql-role
19602 (create-database? #t))))
19606 @deftp {Data Type} postgresql-role
19607 PostgreSQL manages database access permissions using the concept of
19608 roles. A role can be thought of as either a database user, or a group
19609 of database users, depending on how the role is set up. Roles can own
19610 database objects (for example, tables) and can assign privileges on
19611 those objects to other roles to control who has access to which objects.
19617 @item @code{permissions} (default: @code{'(createdb login)})
19618 The role permissions list. Supported permissions are @code{bypassrls},
19619 @code{createdb}, @code{createrole}, @code{login}, @code{replication} and
19622 @item @code{create-database?} (default: @code{#f})
19623 Whether to create a database with the same name as the role.
19628 @deftp {Data Type} postgresql-role-configuration
19629 Data type representing the configuration of
19630 @var{postgresql-role-service-type}.
19633 @item @code{host} (default: @code{"/var/run/postgresql"})
19634 The PostgreSQL host to connect to.
19636 @item @code{log} (default: @code{"/var/log/postgresql_roles.log"})
19637 File name of the log file.
19639 @item @code{roles} (default: @code{'()})
19640 The initial PostgreSQL roles to create.
19644 @subsubheading MariaDB/MySQL
19646 @defvr {Scheme Variable} mysql-service-type
19647 This is the service type for a MySQL or MariaDB database server. Its value
19648 is a @code{mysql-configuration} object that specifies which package to use,
19649 as well as various settings for the @command{mysqld} daemon.
19652 @deftp {Data Type} mysql-configuration
19653 Data type representing the configuration of @var{mysql-service-type}.
19656 @item @code{mysql} (default: @var{mariadb})
19657 Package object of the MySQL database server, can be either @var{mariadb}
19660 For MySQL, a temporary root password will be displayed at activation time.
19661 For MariaDB, the root password is empty.
19663 @item @code{bind-address} (default: @code{"127.0.0.1"})
19664 The IP on which to listen for network connections. Use @code{"0.0.0.0"}
19665 to bind to all available network interfaces.
19667 @item @code{port} (default: @code{3306})
19668 TCP port on which the database server listens for incoming connections.
19670 @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
19671 Socket file to use for local (non-network) connections.
19673 @item @code{extra-content} (default: @code{""})
19674 Additional settings for the @file{my.cnf} configuration file.
19676 @item @code{auto-upgrade?} (default: @code{#t})
19677 Whether to automatically run @command{mysql_upgrade} after starting the
19678 service. This is necessary to upgrade the @dfn{system schema} after
19679 ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
19680 be disabled if you would rather do that manually.
19685 @subsubheading Memcached
19687 @defvr {Scheme Variable} memcached-service-type
19688 This is the service type for the @uref{https://memcached.org/,
19689 Memcached} service, which provides a distributed in memory cache. The
19690 value for the service type is a @code{memcached-configuration} object.
19694 (service memcached-service-type)
19697 @deftp {Data Type} memcached-configuration
19698 Data type representing the configuration of memcached.
19701 @item @code{memcached} (default: @code{memcached})
19702 The Memcached package to use.
19704 @item @code{interfaces} (default: @code{'("0.0.0.0")})
19705 Network interfaces on which to listen.
19707 @item @code{tcp-port} (default: @code{11211})
19708 Port on which to accept connections.
19710 @item @code{udp-port} (default: @code{11211})
19711 Port on which to accept UDP connections on, a value of 0 will disable
19712 listening on a UDP socket.
19714 @item @code{additional-options} (default: @code{'()})
19715 Additional command line options to pass to @code{memcached}.
19719 @subsubheading MongoDB
19721 @defvr {Scheme Variable} mongodb-service-type
19722 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
19723 The value for the service type is a @code{mongodb-configuration} object.
19727 (service mongodb-service-type)
19730 @deftp {Data Type} mongodb-configuration
19731 Data type representing the configuration of mongodb.
19734 @item @code{mongodb} (default: @code{mongodb})
19735 The MongoDB package to use.
19737 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
19738 The configuration file for MongoDB.
19740 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
19741 This value is used to create the directory, so that it exists and is
19742 owned by the mongodb user. It should match the data-directory which
19743 MongoDB is configured to use through the configuration file.
19747 @subsubheading Redis
19749 @defvr {Scheme Variable} redis-service-type
19750 This is the service type for the @uref{https://redis.io/, Redis}
19751 key/value store, whose value is a @code{redis-configuration} object.
19754 @deftp {Data Type} redis-configuration
19755 Data type representing the configuration of redis.
19758 @item @code{redis} (default: @code{redis})
19759 The Redis package to use.
19761 @item @code{bind} (default: @code{"127.0.0.1"})
19762 Network interface on which to listen.
19764 @item @code{port} (default: @code{6379})
19765 Port on which to accept connections on, a value of 0 will disable
19766 listening on a TCP socket.
19768 @item @code{working-directory} (default: @code{"/var/lib/redis"})
19769 Directory in which to store the database and related files.
19773 @node Mail Services
19774 @subsection Mail Services
19778 The @code{(gnu services mail)} module provides Guix service definitions
19779 for email services: IMAP, POP3, and LMTP servers, as well as mail
19780 transport agents (MTAs). Lots of acronyms! These services are detailed
19781 in the subsections below.
19783 @subsubheading Dovecot Service
19785 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
19786 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
19789 By default, Dovecot does not need much configuration; the default
19790 configuration object created by @code{(dovecot-configuration)} will
19791 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
19792 certificate will be generated for TLS-protected connections, though
19793 Dovecot will also listen on cleartext ports by default. There are a
19794 number of options, though, which mail administrators might need to change,
19795 and as is the case with other services, Guix allows the system
19796 administrator to specify these parameters via a uniform Scheme interface.
19798 For example, to specify that mail is located at @code{maildir~/.mail},
19799 one would instantiate the Dovecot service like this:
19802 (dovecot-service #:config
19803 (dovecot-configuration
19804 (mail-location "maildir:~/.mail")))
19807 The available configuration parameters follow. Each parameter
19808 definition is preceded by its type; for example, @samp{string-list foo}
19809 indicates that the @code{foo} parameter should be specified as a list of
19810 strings. There is also a way to specify the configuration as a string,
19811 if you have an old @code{dovecot.conf} file that you want to port over
19812 from some other system; see the end for more details.
19814 @c The following documentation was initially generated by
19815 @c (generate-documentation) in (gnu services mail). Manually maintained
19816 @c documentation is better, so we shouldn't hesitate to edit below as
19817 @c needed. However if the change you want to make to this documentation
19818 @c can be done in an automated way, it's probably easier to change
19819 @c (generate-documentation) than to make it below and have to deal with
19820 @c the churn as dovecot updates.
19822 Available @code{dovecot-configuration} fields are:
19824 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
19825 The dovecot package.
19828 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
19829 A list of IPs or hosts where to listen for connections. @samp{*}
19830 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
19831 interfaces. If you want to specify non-default ports or anything more
19832 complex, customize the address and port fields of the
19833 @samp{inet-listener} of the specific services you are interested in.
19836 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
19837 List of protocols we want to serve. Available protocols include
19838 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
19840 Available @code{protocol-configuration} fields are:
19842 @deftypevr {@code{protocol-configuration} parameter} string name
19843 The name of the protocol.
19846 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
19847 UNIX socket path to the master authentication server to find users.
19848 This is used by imap (for shared users) and lda.
19849 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
19852 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
19853 Space separated list of plugins to load.
19856 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
19857 Maximum number of IMAP connections allowed for a user from each IP
19858 address. NOTE: The username is compared case-sensitively.
19859 Defaults to @samp{10}.
19864 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
19865 List of services to enable. Available services include @samp{imap},
19866 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
19869 Available @code{service-configuration} fields are:
19871 @deftypevr {@code{service-configuration} parameter} string kind
19872 The service kind. Valid values include @code{director},
19873 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
19874 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
19875 @code{tcpwrap}, @code{quota-warning}, or anything else.
19878 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
19879 Listeners for the service. A listener is either a
19880 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
19881 an @code{inet-listener-configuration}.
19882 Defaults to @samp{()}.
19884 Available @code{unix-listener-configuration} fields are:
19886 @deftypevr {@code{unix-listener-configuration} parameter} string path
19887 Path to the file, relative to @code{base-dir} field. This is also used as
19891 @deftypevr {@code{unix-listener-configuration} parameter} string mode
19892 The access mode for the socket.
19893 Defaults to @samp{"0600"}.
19896 @deftypevr {@code{unix-listener-configuration} parameter} string user
19897 The user to own the socket.
19898 Defaults to @samp{""}.
19901 @deftypevr {@code{unix-listener-configuration} parameter} string group
19902 The group to own the socket.
19903 Defaults to @samp{""}.
19907 Available @code{fifo-listener-configuration} fields are:
19909 @deftypevr {@code{fifo-listener-configuration} parameter} string path
19910 Path to the file, relative to @code{base-dir} field. This is also used as
19914 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
19915 The access mode for the socket.
19916 Defaults to @samp{"0600"}.
19919 @deftypevr {@code{fifo-listener-configuration} parameter} string user
19920 The user to own the socket.
19921 Defaults to @samp{""}.
19924 @deftypevr {@code{fifo-listener-configuration} parameter} string group
19925 The group to own the socket.
19926 Defaults to @samp{""}.
19930 Available @code{inet-listener-configuration} fields are:
19932 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
19933 The protocol to listen for.
19936 @deftypevr {@code{inet-listener-configuration} parameter} string address
19937 The address on which to listen, or empty for all addresses.
19938 Defaults to @samp{""}.
19941 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
19942 The port on which to listen.
19945 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
19946 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
19948 Defaults to @samp{#t}.
19953 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
19954 Maximum number of simultaneous client connections per process. Once
19955 this number of connections is received, the next incoming connection
19956 will prompt Dovecot to spawn another process. If set to 0,
19957 @code{default-client-limit} is used instead.
19959 Defaults to @samp{0}.
19963 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
19964 Number of connections to handle before starting a new process.
19965 Typically the only useful values are 0 (unlimited) or 1. 1 is more
19966 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
19967 Defaults to @samp{1}.
19971 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
19972 Maximum number of processes that can exist for this service. If set to
19973 0, @code{default-process-limit} is used instead.
19975 Defaults to @samp{0}.
19979 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
19980 Number of processes to always keep waiting for more connections.
19981 Defaults to @samp{0}.
19984 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
19985 If you set @samp{service-count 0}, you probably need to grow
19987 Defaults to @samp{256000000}.
19992 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
19993 Dict configuration, as created by the @code{dict-configuration}
19996 Available @code{dict-configuration} fields are:
19998 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
19999 A list of key-value pairs that this dict should hold.
20000 Defaults to @samp{()}.
20005 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
20006 A list of passdb configurations, each one created by the
20007 @code{passdb-configuration} constructor.
20009 Available @code{passdb-configuration} fields are:
20011 @deftypevr {@code{passdb-configuration} parameter} string driver
20012 The driver that the passdb should use. Valid values include
20013 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
20015 Defaults to @samp{"pam"}.
20018 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
20019 Space separated list of arguments to the passdb driver.
20020 Defaults to @samp{""}.
20025 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
20026 List of userdb configurations, each one created by the
20027 @code{userdb-configuration} constructor.
20029 Available @code{userdb-configuration} fields are:
20031 @deftypevr {@code{userdb-configuration} parameter} string driver
20032 The driver that the userdb should use. Valid values include
20033 @samp{passwd} and @samp{static}.
20034 Defaults to @samp{"passwd"}.
20037 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
20038 Space separated list of arguments to the userdb driver.
20039 Defaults to @samp{""}.
20042 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
20043 Override fields from passwd.
20044 Defaults to @samp{()}.
20049 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
20050 Plug-in configuration, created by the @code{plugin-configuration}
20054 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
20055 List of namespaces. Each item in the list is created by the
20056 @code{namespace-configuration} constructor.
20058 Available @code{namespace-configuration} fields are:
20060 @deftypevr {@code{namespace-configuration} parameter} string name
20061 Name for this namespace.
20064 @deftypevr {@code{namespace-configuration} parameter} string type
20065 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
20066 Defaults to @samp{"private"}.
20069 @deftypevr {@code{namespace-configuration} parameter} string separator
20070 Hierarchy separator to use. You should use the same separator for
20071 all namespaces or some clients get confused. @samp{/} is usually a good
20072 one. The default however depends on the underlying mail storage
20074 Defaults to @samp{""}.
20077 @deftypevr {@code{namespace-configuration} parameter} string prefix
20078 Prefix required to access this namespace. This needs to be
20079 different for all namespaces. For example @samp{Public/}.
20080 Defaults to @samp{""}.
20083 @deftypevr {@code{namespace-configuration} parameter} string location
20084 Physical location of the mailbox. This is in the same format as
20085 mail_location, which is also the default for it.
20086 Defaults to @samp{""}.
20089 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
20090 There can be only one INBOX, and this setting defines which
20092 Defaults to @samp{#f}.
20095 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
20096 If namespace is hidden, it's not advertised to clients via NAMESPACE
20097 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
20098 useful when converting from another server with different namespaces
20099 which you want to deprecate but still keep working. For example you can
20100 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
20102 Defaults to @samp{#f}.
20105 @deftypevr {@code{namespace-configuration} parameter} boolean list?
20106 Show the mailboxes under this namespace with the LIST command. This
20107 makes the namespace visible for clients that do not support the NAMESPACE
20108 extension. The special @code{children} value lists child mailboxes, but
20109 hides the namespace prefix.
20110 Defaults to @samp{#t}.
20113 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
20114 Namespace handles its own subscriptions. If set to @code{#f}, the
20115 parent namespace handles them. The empty prefix should always have this
20117 Defaults to @samp{#t}.
20120 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
20121 List of predefined mailboxes in this namespace.
20122 Defaults to @samp{()}.
20124 Available @code{mailbox-configuration} fields are:
20126 @deftypevr {@code{mailbox-configuration} parameter} string name
20127 Name for this mailbox.
20130 @deftypevr {@code{mailbox-configuration} parameter} string auto
20131 @samp{create} will automatically create this mailbox.
20132 @samp{subscribe} will both create and subscribe to the mailbox.
20133 Defaults to @samp{"no"}.
20136 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
20137 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
20138 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
20139 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
20140 Defaults to @samp{()}.
20147 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
20148 Base directory where to store runtime data.
20149 Defaults to @samp{"/var/run/dovecot/"}.
20152 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
20153 Greeting message for clients.
20154 Defaults to @samp{"Dovecot ready."}.
20157 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
20158 List of trusted network ranges. Connections from these IPs are
20159 allowed to override their IP addresses and ports (for logging and for
20160 authentication checks). @samp{disable-plaintext-auth} is also ignored
20161 for these networks. Typically you would specify your IMAP proxy servers
20163 Defaults to @samp{()}.
20166 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
20167 List of login access check sockets (e.g.@: tcpwrap).
20168 Defaults to @samp{()}.
20171 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
20172 Show more verbose process titles (in ps). Currently shows user name
20173 and IP address. Useful for seeing who is actually using the IMAP
20174 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
20176 Defaults to @samp{#f}.
20179 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
20180 Should all processes be killed when Dovecot master process shuts down.
20181 Setting this to @code{#f} means that Dovecot can be upgraded without
20182 forcing existing client connections to close (although that could also
20183 be a problem if the upgrade is e.g.@: due to a security fix).
20184 Defaults to @samp{#t}.
20187 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
20188 If non-zero, run mail commands via this many connections to doveadm
20189 server, instead of running them directly in the same process.
20190 Defaults to @samp{0}.
20193 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
20194 UNIX socket or host:port used for connecting to doveadm server.
20195 Defaults to @samp{"doveadm-server"}.
20198 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
20199 List of environment variables that are preserved on Dovecot startup
20200 and passed down to all of its child processes. You can also give
20201 key=value pairs to always set specific settings.
20204 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
20205 Disable LOGIN command and all other plaintext authentications unless
20206 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
20207 matches the local IP (i.e.@: you're connecting from the same computer),
20208 the connection is considered secure and plaintext authentication is
20209 allowed. See also ssl=required setting.
20210 Defaults to @samp{#t}.
20213 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
20214 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
20215 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
20216 for caching to be used.
20217 Defaults to @samp{0}.
20220 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
20221 Time to live for cached data. After TTL expires the cached record
20222 is no longer used, *except* if the main database lookup returns internal
20223 failure. We also try to handle password changes automatically: If
20224 user's previous authentication was successful, but this one wasn't, the
20225 cache isn't used. For now this works only with plaintext
20227 Defaults to @samp{"1 hour"}.
20230 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
20231 TTL for negative hits (user not found, password mismatch).
20232 0 disables caching them completely.
20233 Defaults to @samp{"1 hour"}.
20236 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
20237 List of realms for SASL authentication mechanisms that need them.
20238 You can leave it empty if you don't want to support multiple realms.
20239 Many clients simply use the first one listed here, so keep the default
20241 Defaults to @samp{()}.
20244 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
20245 Default realm/domain to use if none was specified. This is used for
20246 both SASL realms and appending @@domain to username in plaintext
20248 Defaults to @samp{""}.
20251 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
20252 List of allowed characters in username. If the user-given username
20253 contains a character not listed in here, the login automatically fails.
20254 This is just an extra check to make sure user can't exploit any
20255 potential quote escaping vulnerabilities with SQL/LDAP databases. If
20256 you want to allow all characters, set this value to empty.
20257 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
20260 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
20261 Username character translations before it's looked up from
20262 databases. The value contains series of from -> to characters. For
20263 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
20264 translated to @samp{@@}.
20265 Defaults to @samp{""}.
20268 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
20269 Username formatting before it's looked up from databases. You can
20270 use the standard variables here, e.g.@: %Lu would lowercase the username,
20271 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
20272 change the @samp{@@} into @samp{-AT-}. This translation is done after
20273 @samp{auth-username-translation} changes.
20274 Defaults to @samp{"%Lu"}.
20277 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
20278 If you want to allow master users to log in by specifying the master
20279 username within the normal username string (i.e.@: not using SASL
20280 mechanism's support for it), you can specify the separator character
20281 here. The format is then <username><separator><master username>.
20282 UW-IMAP uses @samp{*} as the separator, so that could be a good
20284 Defaults to @samp{""}.
20287 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
20288 Username to use for users logging in with ANONYMOUS SASL
20290 Defaults to @samp{"anonymous"}.
20293 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
20294 Maximum number of dovecot-auth worker processes. They're used to
20295 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
20296 They're automatically created and destroyed as needed.
20297 Defaults to @samp{30}.
20300 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
20301 Host name to use in GSSAPI principal names. The default is to use
20302 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
20303 allow all keytab entries.
20304 Defaults to @samp{""}.
20307 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
20308 Kerberos keytab to use for the GSSAPI mechanism. Will use the
20309 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
20310 need to change the auth service to run as root to be able to read this
20312 Defaults to @samp{""}.
20315 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
20316 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
20317 and @samp{ntlm-auth} helper.
20318 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
20319 Defaults to @samp{#f}.
20322 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
20323 Path for Samba's @samp{ntlm-auth} helper binary.
20324 Defaults to @samp{"/usr/bin/ntlm_auth"}.
20327 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
20328 Time to delay before replying to failed authentications.
20329 Defaults to @samp{"2 secs"}.
20332 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
20333 Require a valid SSL client certificate or the authentication
20335 Defaults to @samp{#f}.
20338 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
20339 Take the username from client's SSL certificate, using
20340 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
20342 Defaults to @samp{#f}.
20345 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
20346 List of wanted authentication mechanisms. Supported mechanisms are:
20347 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
20348 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
20349 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
20350 @samp{disable-plaintext-auth} setting.
20353 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
20354 List of IPs or hostnames to all director servers, including ourself.
20355 Ports can be specified as ip:port. The default port is the same as what
20356 director service's @samp{inet-listener} is using.
20357 Defaults to @samp{()}.
20360 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
20361 List of IPs or hostnames to all backend mail servers. Ranges are
20362 allowed too, like 10.0.0.10-10.0.0.30.
20363 Defaults to @samp{()}.
20366 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
20367 How long to redirect users to a specific server after it no longer
20368 has any connections.
20369 Defaults to @samp{"15 min"}.
20372 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
20373 How the username is translated before being hashed. Useful values
20374 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
20375 are shared within domain.
20376 Defaults to @samp{"%Lu"}.
20379 @deftypevr {@code{dovecot-configuration} parameter} string log-path
20380 Log file to use for error messages. @samp{syslog} logs to syslog,
20381 @samp{/dev/stderr} logs to stderr.
20382 Defaults to @samp{"syslog"}.
20385 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
20386 Log file to use for informational messages. Defaults to
20388 Defaults to @samp{""}.
20391 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
20392 Log file to use for debug messages. Defaults to
20393 @samp{info-log-path}.
20394 Defaults to @samp{""}.
20397 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
20398 Syslog facility to use if you're logging to syslog. Usually if you
20399 don't want to use @samp{mail}, you'll use local0..local7. Also other
20400 standard facilities are supported.
20401 Defaults to @samp{"mail"}.
20404 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
20405 Log unsuccessful authentication attempts and the reasons why they
20407 Defaults to @samp{#f}.
20410 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
20411 In case of password mismatches, log the attempted password. Valid
20412 values are no, plain and sha1. sha1 can be useful for detecting brute
20413 force password attempts vs. user simply trying the same password over
20414 and over again. You can also truncate the value to n chars by appending
20415 ":n" (e.g.@: sha1:6).
20416 Defaults to @samp{"no"}.
20419 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
20420 Even more verbose logging for debugging purposes. Shows for example
20422 Defaults to @samp{#f}.
20425 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
20426 In case of password mismatches, log the passwords and used scheme so
20427 the problem can be debugged. Enabling this also enables
20429 Defaults to @samp{#f}.
20432 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
20433 Enable mail process debugging. This can help you figure out why
20434 Dovecot isn't finding your mails.
20435 Defaults to @samp{#f}.
20438 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
20439 Show protocol level SSL errors.
20440 Defaults to @samp{#f}.
20443 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
20444 Prefix for each line written to log file. % codes are in
20445 strftime(3) format.
20446 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
20449 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
20450 List of elements we want to log. The elements which have a
20451 non-empty variable value are joined together to form a comma-separated
20455 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
20456 Login log format. %s contains @samp{login-log-format-elements}
20457 string, %$ contains the data we want to log.
20458 Defaults to @samp{"%$: %s"}.
20461 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
20462 Log prefix for mail processes. See doc/wiki/Variables.txt for list
20463 of possible variables you can use.
20464 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
20467 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
20468 Format to use for logging mail deliveries. You can use variables:
20471 Delivery status message (e.g.@: @samp{saved to INBOX})
20483 Defaults to @samp{"msgid=%m: %$"}.
20486 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
20487 Location for users' mailboxes. The default is empty, which means
20488 that Dovecot tries to find the mailboxes automatically. This won't work
20489 if the user doesn't yet have any mail, so you should explicitly tell
20490 Dovecot the full location.
20492 If you're using mbox, giving a path to the INBOX
20493 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
20494 where the other mailboxes are kept. This is called the @emph{root mail
20495 directory}, and it must be the first path given in the
20496 @samp{mail-location} setting.
20498 There are a few special variables you can use, e.g.:
20504 user part in user@@domain, same as %u if there's no domain
20506 domain part in user@@domain, empty if there's no domain
20511 See doc/wiki/Variables.txt for full list. Some examples:
20513 @item maildir:~/Maildir
20514 @item mbox:~/mail:INBOX=/var/mail/%u
20515 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
20517 Defaults to @samp{""}.
20520 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
20521 System user and group used to access mails. If you use multiple,
20522 userdb can override these by returning uid or gid fields. You can use
20523 either numbers or names. <doc/wiki/UserIds.txt>.
20524 Defaults to @samp{""}.
20527 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
20529 Defaults to @samp{""}.
20532 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
20533 Group to enable temporarily for privileged operations. Currently
20534 this is used only with INBOX when either its initial creation or
20535 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
20537 Defaults to @samp{""}.
20540 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
20541 Grant access to these supplementary groups for mail processes.
20542 Typically these are used to set up access to shared mailboxes. Note
20543 that it may be dangerous to set these if users can create symlinks
20544 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
20545 could allow a user to delete others' mailboxes, or @code{ln -s
20546 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
20550 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
20551 Allow full file system access to clients. There's no access checks
20552 other than what the operating system does for the active UID/GID@. It
20553 works with both maildir and mboxes, allowing you to prefix mailboxes
20554 names with e.g.@: @file{/path/} or @file{~user/}.
20555 Defaults to @samp{#f}.
20558 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
20559 Don't use @code{mmap()} at all. This is required if you store indexes to
20560 shared file systems (NFS or clustered file system).
20561 Defaults to @samp{#f}.
20564 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
20565 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
20566 supports @samp{O_EXCL} since version 3, so this should be safe to use
20567 nowadays by default.
20568 Defaults to @samp{#t}.
20571 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
20572 When to use fsync() or fdatasync() calls:
20575 Whenever necessary to avoid losing important data
20577 Useful with e.g.@: NFS when @code{write()}s are delayed
20579 Never use it (best performance, but crashes can lose data).
20581 Defaults to @samp{"optimized"}.
20584 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
20585 Mail storage exists in NFS@. Set this to yes to make Dovecot flush
20586 NFS caches whenever needed. If you're using only a single mail server
20588 Defaults to @samp{#f}.
20591 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
20592 Mail index files also exist in NFS@. Setting this to yes requires
20593 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
20594 Defaults to @samp{#f}.
20597 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
20598 Locking method for index files. Alternatives are fcntl, flock and
20599 dotlock. Dotlocking uses some tricks which may create more disk I/O
20600 than other locking methods. NFS users: flock doesn't work, remember to
20601 change @samp{mmap-disable}.
20602 Defaults to @samp{"fcntl"}.
20605 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
20606 Directory in which LDA/LMTP temporarily stores incoming mails >128
20608 Defaults to @samp{"/tmp"}.
20611 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
20612 Valid UID range for users. This is mostly to make sure that users can't
20613 log in as daemons or other system users. Note that denying root logins is
20614 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
20616 Defaults to @samp{500}.
20619 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
20621 Defaults to @samp{0}.
20624 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
20625 Valid GID range for users. Users having non-valid GID as primary group ID
20626 aren't allowed to log in. If user belongs to supplementary groups with
20627 non-valid GIDs, those groups are not set.
20628 Defaults to @samp{1}.
20631 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
20633 Defaults to @samp{0}.
20636 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
20637 Maximum allowed length for mail keyword name. It's only forced when
20638 trying to create new keywords.
20639 Defaults to @samp{50}.
20642 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
20643 List of directories under which chrooting is allowed for mail
20644 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
20645 too). This setting doesn't affect @samp{login-chroot}
20646 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
20647 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
20648 which local users can modify, that may lead to root exploit. Usually
20649 this should be done only if you don't allow shell access for users.
20650 <doc/wiki/Chrooting.txt>.
20651 Defaults to @samp{()}.
20654 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
20655 Default chroot directory for mail processes. This can be overridden
20656 for specific users in user database by giving @samp{/./} in user's home
20657 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
20658 there is no real need to do chrooting, Dovecot doesn't allow users to
20659 access files outside their mail directory anyway. If your home
20660 directories are prefixed with the chroot directory, append @samp{/.} to
20661 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
20662 Defaults to @samp{""}.
20665 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
20666 UNIX socket path to master authentication server to find users.
20667 This is used by imap (for shared users) and lda.
20668 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
20671 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
20672 Directory where to look up mail plugins.
20673 Defaults to @samp{"/usr/lib/dovecot"}.
20676 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
20677 List of plugins to load for all services. Plugins specific to IMAP,
20678 LDA, etc.@: are added to this list in their own .conf files.
20679 Defaults to @samp{()}.
20682 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
20683 The minimum number of mails in a mailbox before updates are done to
20684 cache file. This allows optimizing Dovecot's behavior to do less disk
20685 writes at the cost of more disk reads.
20686 Defaults to @samp{0}.
20689 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
20690 When IDLE command is running, mailbox is checked once in a while to
20691 see if there are any new mails or other changes. This setting defines
20692 the minimum time to wait between those checks. Dovecot can also use
20693 dnotify, inotify and kqueue to find out immediately when changes
20695 Defaults to @samp{"30 secs"}.
20698 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
20699 Save mails with CR+LF instead of plain LF@. This makes sending those
20700 mails take less CPU, especially with sendfile() syscall with Linux and
20701 FreeBSD@. But it also creates a bit more disk I/O which may just make it
20702 slower. Also note that if other software reads the mboxes/maildirs,
20703 they may handle the extra CRs wrong and cause problems.
20704 Defaults to @samp{#f}.
20707 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
20708 By default LIST command returns all entries in maildir beginning
20709 with a dot. Enabling this option makes Dovecot return only entries
20710 which are directories. This is done by stat()ing each entry, so it
20711 causes more disk I/O.
20712 (For systems setting struct @samp{dirent->d_type} this check is free
20713 and it's done always regardless of this setting).
20714 Defaults to @samp{#f}.
20717 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
20718 When copying a message, do it with hard links whenever possible.
20719 This makes the performance much better, and it's unlikely to have any
20721 Defaults to @samp{#t}.
20724 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
20725 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
20726 directory only when its mtime changes unexpectedly or when we can't find
20727 the mail otherwise.
20728 Defaults to @samp{#f}.
20731 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
20732 Which locking methods to use for locking mbox. There are four
20737 Create <mailbox>.lock file. This is the oldest and most NFS-safe
20738 solution. If you want to use /var/mail/ like directory, the users will
20739 need write access to that directory.
20741 Same as dotlock, but if it fails because of permissions or because there
20742 isn't enough disk space, just skip it.
20744 Use this if possible. Works with NFS too if lockd is used.
20746 May not exist in all systems. Doesn't work with NFS.
20748 May not exist in all systems. Doesn't work with NFS.
20751 You can use multiple locking methods; if you do the order they're declared
20752 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
20753 locking methods as well. Some operating systems don't allow using some of
20754 them simultaneously.
20757 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
20761 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
20762 Maximum time to wait for lock (all of them) before aborting.
20763 Defaults to @samp{"5 mins"}.
20766 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
20767 If dotlock exists but the mailbox isn't modified in any way,
20768 override the lock file after this much time.
20769 Defaults to @samp{"2 mins"}.
20772 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
20773 When mbox changes unexpectedly we have to fully read it to find out
20774 what changed. If the mbox is large this can take a long time. Since
20775 the change is usually just a newly appended mail, it'd be faster to
20776 simply read the new mails. If this setting is enabled, Dovecot does
20777 this but still safely fallbacks to re-reading the whole mbox file
20778 whenever something in mbox isn't how it's expected to be. The only real
20779 downside to this setting is that if some other MUA changes message
20780 flags, Dovecot doesn't notice it immediately. Note that a full sync is
20781 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
20782 Defaults to @samp{#t}.
20785 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
20786 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
20787 EXAMINE, EXPUNGE or CHECK commands. If this is set,
20788 @samp{mbox-dirty-syncs} is ignored.
20789 Defaults to @samp{#f}.
20792 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
20793 Delay writing mbox headers until doing a full write sync (EXPUNGE
20794 and CHECK commands and when closing the mailbox). This is especially
20795 useful for POP3 where clients often delete all mails. The downside is
20796 that our changes aren't immediately visible to other MUAs.
20797 Defaults to @samp{#t}.
20800 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
20801 If mbox size is smaller than this (e.g.@: 100k), don't write index
20802 files. If an index file already exists it's still read, just not
20804 Defaults to @samp{0}.
20807 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
20808 Maximum dbox file size until it's rotated.
20809 Defaults to @samp{10000000}.
20812 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
20813 Maximum dbox file age until it's rotated. Typically in days. Day
20814 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
20816 Defaults to @samp{"1d"}.
20819 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
20820 When creating new mdbox files, immediately preallocate their size to
20821 @samp{mdbox-rotate-size}. This setting currently works only in Linux
20822 with some file systems (ext4, xfs).
20823 Defaults to @samp{#f}.
20826 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
20827 sdbox and mdbox support saving mail attachments to external files,
20828 which also allows single instance storage for them. Other backends
20829 don't support this for now.
20831 WARNING: This feature hasn't been tested much yet. Use at your own risk.
20833 Directory root where to store mail attachments. Disabled, if empty.
20834 Defaults to @samp{""}.
20837 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
20838 Attachments smaller than this aren't saved externally. It's also
20839 possible to write a plugin to disable saving specific attachments
20841 Defaults to @samp{128000}.
20844 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
20845 File system backend to use for saving attachments:
20848 No SiS done by Dovecot (but this might help FS's own deduplication)
20850 SiS with immediate byte-by-byte comparison during saving
20851 @item sis-queue posix
20852 SiS with delayed comparison and deduplication.
20854 Defaults to @samp{"sis posix"}.
20857 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
20858 Hash format to use in attachment filenames. You can add any text and
20859 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
20860 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
20861 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
20862 Defaults to @samp{"%@{sha1@}"}.
20865 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
20867 Defaults to @samp{100}.
20870 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
20872 Defaults to @samp{1000}.
20875 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
20876 Default VSZ (virtual memory size) limit for service processes.
20877 This is mainly intended to catch and kill processes that leak memory
20878 before they eat up everything.
20879 Defaults to @samp{256000000}.
20882 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
20883 Login user is internally used by login processes. This is the most
20884 untrusted user in Dovecot system. It shouldn't have access to anything
20886 Defaults to @samp{"dovenull"}.
20889 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
20890 Internal user is used by unprivileged processes. It should be
20891 separate from login user, so that login processes can't disturb other
20893 Defaults to @samp{"dovecot"}.
20896 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
20897 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
20898 Defaults to @samp{"required"}.
20901 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
20902 PEM encoded X.509 SSL/TLS certificate (public key).
20903 Defaults to @samp{"</etc/dovecot/default.pem"}.
20906 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
20907 PEM encoded SSL/TLS private key. The key is opened before
20908 dropping root privileges, so keep the key file unreadable by anyone but
20910 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
20913 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
20914 If key file is password protected, give the password here.
20915 Alternatively give it when starting dovecot with -p parameter. Since
20916 this file is often world-readable, you may want to place this setting
20917 instead to a different.
20918 Defaults to @samp{""}.
20921 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
20922 PEM encoded trusted certificate authority. Set this only if you
20923 intend to use @samp{ssl-verify-client-cert? #t}. The file should
20924 contain the CA certificate(s) followed by the matching
20925 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
20926 Defaults to @samp{""}.
20929 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
20930 Require that CRL check succeeds for client certificates.
20931 Defaults to @samp{#t}.
20934 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
20935 Request client to send a certificate. If you also want to require
20936 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
20937 Defaults to @samp{#f}.
20940 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
20941 Which field from certificate to use for username. commonName and
20942 x500UniqueIdentifier are the usual choices. You'll also need to set
20943 @samp{auth-ssl-username-from-cert? #t}.
20944 Defaults to @samp{"commonName"}.
20947 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
20948 Minimum SSL protocol version to accept.
20949 Defaults to @samp{"TLSv1"}.
20952 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
20953 SSL ciphers to use.
20954 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
20957 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
20958 SSL crypto device to use, for valid values run "openssl engine".
20959 Defaults to @samp{""}.
20962 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
20963 Address to use when sending rejection mails.
20964 %d expands to recipient domain.
20965 Defaults to @samp{"postmaster@@%d"}.
20968 @deftypevr {@code{dovecot-configuration} parameter} string hostname
20969 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
20970 and in LMTP replies. Default is the system's real hostname@@domain.
20971 Defaults to @samp{""}.
20974 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
20975 If user is over quota, return with temporary failure instead of
20977 Defaults to @samp{#f}.
20980 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
20981 Binary to use for sending mails.
20982 Defaults to @samp{"/usr/sbin/sendmail"}.
20985 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
20986 If non-empty, send mails via this SMTP host[:port] instead of
20988 Defaults to @samp{""}.
20991 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
20992 Subject: header to use for rejection mails. You can use the same
20993 variables as for @samp{rejection-reason} below.
20994 Defaults to @samp{"Rejected: %s"}.
20997 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
20998 Human readable error message for rejection mails. You can use
21011 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
21014 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
21015 Delimiter character between local-part and detail in email
21017 Defaults to @samp{"+"}.
21020 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
21021 Header where the original recipient address (SMTP's RCPT TO:
21022 address) is taken from if not available elsewhere. With dovecot-lda -a
21023 parameter overrides this. A commonly used header for this is
21025 Defaults to @samp{""}.
21028 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
21029 Should saving a mail to a nonexistent mailbox automatically create
21031 Defaults to @samp{#f}.
21034 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
21035 Should automatically created mailboxes be also automatically
21037 Defaults to @samp{#f}.
21040 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
21041 Maximum IMAP command line length. Some clients generate very long
21042 command lines with huge mailboxes, so you may need to raise this if you
21043 get "Too long argument" or "IMAP command line too large" errors
21045 Defaults to @samp{64000}.
21048 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
21049 IMAP logout format string:
21052 total number of bytes read from client
21054 total number of bytes sent to client.
21056 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
21057 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@}"}.
21060 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
21061 Override the IMAP CAPABILITY response. If the value begins with '+',
21062 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
21063 Defaults to @samp{""}.
21066 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
21067 How long to wait between "OK Still here" notifications when client
21069 Defaults to @samp{"2 mins"}.
21072 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
21073 ID field names and values to send to clients. Using * as the value
21074 makes Dovecot use the default value. The following fields have default
21075 values currently: name, version, os, os-version, support-url,
21077 Defaults to @samp{""}.
21080 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
21081 ID fields sent by client to log. * means everything.
21082 Defaults to @samp{""}.
21085 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
21086 Workarounds for various client bugs:
21089 @item delay-newmail
21090 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
21091 CHECK commands. Some clients ignore them otherwise, for example OSX
21092 Mail (<v2.1). Outlook Express breaks more badly though, without this it
21093 may show user "Message no longer in server" errors. Note that OE6
21094 still breaks even with this workaround if synchronization is set to
21097 @item tb-extra-mailbox-sep
21098 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
21099 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
21100 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
21102 @item tb-lsub-flags
21103 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
21104 This makes Thunderbird realize they aren't selectable and show them
21105 greyed out, instead of only later giving "not selectable" popup error.
21107 Defaults to @samp{()}.
21110 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
21111 Host allowed in URLAUTH URLs sent by client. "*" allows all.
21112 Defaults to @samp{""}.
21116 Whew! Lots of configuration options. The nice thing about it though is
21117 that Guix has a complete interface to Dovecot's configuration
21118 language. This allows not only a nice way to declare configurations,
21119 but also offers reflective capabilities as well: users can write code to
21120 inspect and transform configurations from within Scheme.
21122 However, it could be that you just want to get a @code{dovecot.conf} up
21123 and running. In that case, you can pass an
21124 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
21125 @code{dovecot-service}. As its name indicates, an opaque configuration
21126 does not have easy reflective capabilities.
21128 Available @code{opaque-dovecot-configuration} fields are:
21130 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
21131 The dovecot package.
21134 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
21135 The contents of the @code{dovecot.conf}, as a string.
21138 For example, if your @code{dovecot.conf} is just the empty string, you
21139 could instantiate a dovecot service like this:
21142 (dovecot-service #:config
21143 (opaque-dovecot-configuration
21147 @subsubheading OpenSMTPD Service
21149 @deffn {Scheme Variable} opensmtpd-service-type
21150 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
21151 service, whose value should be an @code{opensmtpd-configuration} object
21152 as in this example:
21155 (service opensmtpd-service-type
21156 (opensmtpd-configuration
21157 (config-file (local-file "./my-smtpd.conf"))))
21161 @deftp {Data Type} opensmtpd-configuration
21162 Data type representing the configuration of opensmtpd.
21165 @item @code{package} (default: @var{opensmtpd})
21166 Package object of the OpenSMTPD SMTP server.
21168 @item @code{config-file} (default: @code{%default-opensmtpd-file})
21169 File-like object of the OpenSMTPD configuration file to use. By default
21170 it listens on the loopback network interface, and allows for mail from
21171 users and daemons on the local machine, as well as permitting email to
21172 remote servers. Run @command{man smtpd.conf} for more information.
21177 @subsubheading Exim Service
21179 @cindex mail transfer agent (MTA)
21180 @cindex MTA (mail transfer agent)
21183 @deffn {Scheme Variable} exim-service-type
21184 This is the type of the @uref{https://exim.org, Exim} mail transfer
21185 agent (MTA), whose value should be an @code{exim-configuration} object
21186 as in this example:
21189 (service exim-service-type
21190 (exim-configuration
21191 (config-file (local-file "./my-exim.conf"))))
21195 In order to use an @code{exim-service-type} service you must also have a
21196 @code{mail-aliases-service-type} service present in your
21197 @code{operating-system} (even if it has no aliases).
21199 @deftp {Data Type} exim-configuration
21200 Data type representing the configuration of exim.
21203 @item @code{package} (default: @var{exim})
21204 Package object of the Exim server.
21206 @item @code{config-file} (default: @code{#f})
21207 File-like object of the Exim configuration file to use. If its value is
21208 @code{#f} then use the default configuration file from the package
21209 provided in @code{package}. The resulting configuration file is loaded
21210 after setting the @code{exim_user} and @code{exim_group} configuration
21216 @subsubheading Getmail service
21221 @deffn {Scheme Variable} getmail-service-type
21222 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
21223 mail retriever, whose value should be an @code{getmail-configuration}.
21226 Available @code{getmail-configuration} fields are:
21228 @deftypevr {@code{getmail-configuration} parameter} symbol name
21229 A symbol to identify the getmail service.
21231 Defaults to @samp{"unset"}.
21235 @deftypevr {@code{getmail-configuration} parameter} package package
21236 The getmail package to use.
21240 @deftypevr {@code{getmail-configuration} parameter} string user
21241 The user to run getmail as.
21243 Defaults to @samp{"getmail"}.
21247 @deftypevr {@code{getmail-configuration} parameter} string group
21248 The group to run getmail as.
21250 Defaults to @samp{"getmail"}.
21254 @deftypevr {@code{getmail-configuration} parameter} string directory
21255 The getmail directory to use.
21257 Defaults to @samp{"/var/lib/getmail/default"}.
21261 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
21262 The getmail configuration file to use.
21264 Available @code{getmail-configuration-file} fields are:
21266 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
21267 What mail account to retrieve mail from, and how to access that account.
21269 Available @code{getmail-retriever-configuration} fields are:
21271 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
21272 The type of mail retriever to use. Valid values include @samp{passwd}
21275 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
21279 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
21280 Username to login to the mail server with.
21282 Defaults to @samp{unset}.
21286 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
21287 Username to login to the mail server with.
21289 Defaults to @samp{unset}.
21293 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
21294 Port number to connect to.
21296 Defaults to @samp{#f}.
21300 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
21301 Override fields from passwd.
21303 Defaults to @samp{""}.
21307 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
21308 Override fields from passwd.
21310 Defaults to @samp{()}.
21314 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
21315 PEM-formatted key file to use for the TLS negotiation.
21317 Defaults to @samp{""}.
21321 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
21322 PEM-formatted certificate file to use for the TLS negotiation.
21324 Defaults to @samp{""}.
21328 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
21329 CA certificates to use.
21331 Defaults to @samp{""}.
21335 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
21336 Extra retriever parameters.
21338 Defaults to @samp{()}.
21344 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
21345 What to do with retrieved messages.
21347 Available @code{getmail-destination-configuration} fields are:
21349 @deftypevr {@code{getmail-destination-configuration} parameter} string type
21350 The type of mail destination. Valid values include @samp{Maildir},
21351 @samp{Mboxrd} and @samp{MDA_external}.
21353 Defaults to @samp{unset}.
21357 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
21358 The path option for the mail destination. The behaviour depends on the
21361 Defaults to @samp{""}.
21365 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
21366 Extra destination parameters
21368 Defaults to @samp{()}.
21374 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
21377 Available @code{getmail-options-configuration} fields are:
21379 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
21380 If set to @samp{0}, getmail will only print warnings and errors. A
21381 value of @samp{1} means that messages will be printed about retrieving
21382 and deleting messages. If set to @samp{2}, getmail will print messages
21383 about each of it's actions.
21385 Defaults to @samp{1}.
21389 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
21390 If true, getmail will retrieve all available messages. Otherwise it
21391 will only retrieve messages it hasn't seen previously.
21393 Defaults to @samp{#t}.
21397 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
21398 If set to true, messages will be deleted from the server after
21399 retrieving and successfully delivering them. Otherwise, messages will
21400 be left on the server.
21402 Defaults to @samp{#f}.
21406 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
21407 Getmail will delete messages this number of days after seeing them, if
21408 they have been delivered. This means messages will be left on the
21409 server this number of days after delivering them. A value of @samp{0}
21410 disabled this feature.
21412 Defaults to @samp{0}.
21416 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
21417 Delete messages larger than this of bytes after retrieving them, even if
21418 the delete and delete-after options are disabled. A value of @samp{0}
21419 disables this feature.
21421 Defaults to @samp{0}.
21425 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
21426 Retrieve messages totalling up to this number of bytes before closing
21427 the session with the server. A value of @samp{0} disables this feature.
21429 Defaults to @samp{0}.
21433 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
21434 Don't retrieve messages larger than this number of bytes. A value of
21435 @samp{0} disables this feature.
21437 Defaults to @samp{0}.
21441 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
21442 If true, getmail will add a Delivered-To header to messages.
21444 Defaults to @samp{#t}.
21448 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
21449 If set, getmail adds a Received header to the messages.
21451 Defaults to @samp{#t}.
21455 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
21456 Getmail will record a log of its actions to the named file. A value of
21457 @samp{""} disables this feature.
21459 Defaults to @samp{""}.
21463 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
21464 If true, getmail will record a log of its actions using the system
21467 Defaults to @samp{#f}.
21471 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
21472 If true, getmail will log information about messages not retrieved and
21473 the reason for not retrieving them, as well as starting and ending
21476 Defaults to @samp{#f}.
21480 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
21481 Extra options to include.
21483 Defaults to @samp{()}.
21491 @deftypevr {@code{getmail-configuration} parameter} list idle
21492 A list of mailboxes that getmail should wait on the server for new mail
21493 notifications. This depends on the server supporting the IDLE
21496 Defaults to @samp{()}.
21500 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
21501 Environment variables to set for getmail.
21503 Defaults to @samp{()}.
21507 @subsubheading Mail Aliases Service
21509 @cindex email aliases
21510 @cindex aliases, for email addresses
21512 @deffn {Scheme Variable} mail-aliases-service-type
21513 This is the type of the service which provides @code{/etc/aliases},
21514 specifying how to deliver mail to users on this system.
21517 (service mail-aliases-service-type
21518 '(("postmaster" "bob")
21519 ("bob" "bob@@example.com" "bob@@example2.com")))
21523 The configuration for a @code{mail-aliases-service-type} service is an
21524 association list denoting how to deliver mail that comes to this
21525 system. Each entry is of the form @code{(alias addresses ...)}, with
21526 @code{alias} specifying the local alias and @code{addresses} specifying
21527 where to deliver this user's mail.
21529 The aliases aren't required to exist as users on the local system. In
21530 the above example, there doesn't need to be a @code{postmaster} entry in
21531 the @code{operating-system}'s @code{user-accounts} in order to deliver
21532 the @code{postmaster} mail to @code{bob} (which subsequently would
21533 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
21535 @subsubheading GNU Mailutils IMAP4 Daemon
21536 @cindex GNU Mailutils IMAP4 Daemon
21538 @deffn {Scheme Variable} imap4d-service-type
21539 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
21540 mailutils, GNU Mailutils Manual}), whose value should be an
21541 @code{imap4d-configuration} object as in this example:
21544 (service imap4d-service-type
21545 (imap4d-configuration
21546 (config-file (local-file "imap4d.conf"))))
21550 @deftp {Data Type} imap4d-configuration
21551 Data type representing the configuration of @command{imap4d}.
21554 @item @code{package} (default: @code{mailutils})
21555 The package that provides @command{imap4d}.
21557 @item @code{config-file} (default: @code{%default-imap4d-config-file})
21558 File-like object of the configuration file to use, by default it will listen
21559 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
21560 Mailutils Manual}, for details.
21565 @subsubheading Radicale Service
21569 @deffn {Scheme Variable} radicale-service-type
21570 This is the type of the @uref{https://radicale.org, Radicale} CalDAV/CardDAV
21571 server whose value should be a @code{radicale-configuration}.
21574 @deftp {Data Type} radicale-configuration
21575 Data type representing the configuration of @command{radicale}.
21578 @item @code{package} (default: @code{radicale})
21579 The package that provides @command{radicale}.
21581 @item @code{config-file} (default: @code{%default-radicale-config-file})
21582 File-like object of the configuration file to use, by default it will listen
21583 on TCP port 5232 of @code{localhost} and use the @code{htpasswd} file at
21584 @file{/var/lib/radicale/users} with no (@code{plain}) encryption.
21589 @node Messaging Services
21590 @subsection Messaging Services
21595 The @code{(gnu services messaging)} module provides Guix service
21596 definitions for messaging services. Currently it provides the following
21599 @subsubheading Prosody Service
21601 @deffn {Scheme Variable} prosody-service-type
21602 This is the type for the @uref{https://prosody.im, Prosody XMPP
21603 communication server}. Its value must be a @code{prosody-configuration}
21604 record as in this example:
21607 (service prosody-service-type
21608 (prosody-configuration
21609 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
21612 (int-component-configuration
21613 (hostname "conference.example.net")
21615 (mod-muc (mod-muc-configuration)))))
21618 (virtualhost-configuration
21619 (domain "example.net"))))))
21622 See below for details about @code{prosody-configuration}.
21626 By default, Prosody does not need much configuration. Only one
21627 @code{virtualhosts} field is needed: it specifies the domain you wish
21630 You can perform various sanity checks on the generated configuration
21631 with the @code{prosodyctl check} command.
21633 Prosodyctl will also help you to import certificates from the
21634 @code{letsencrypt} directory so that the @code{prosody} user can access
21635 them. See @url{https://prosody.im/doc/letsencrypt}.
21638 prosodyctl --root cert import /etc/letsencrypt/live
21641 The available configuration parameters follow. Each parameter
21642 definition is preceded by its type; for example, @samp{string-list foo}
21643 indicates that the @code{foo} parameter should be specified as a list of
21644 strings. Types starting with @code{maybe-} denote parameters that won't
21645 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
21647 There is also a way to specify the configuration as a string, if you
21648 have an old @code{prosody.cfg.lua} file that you want to port over from
21649 some other system; see the end for more details.
21651 The @code{file-object} type designates either a file-like object
21652 (@pxref{G-Expressions, file-like objects}) or a file name.
21654 @c The following documentation was initially generated by
21655 @c (generate-documentation) in (gnu services messaging). Manually maintained
21656 @c documentation is better, so we shouldn't hesitate to edit below as
21657 @c needed. However if the change you want to make to this documentation
21658 @c can be done in an automated way, it's probably easier to change
21659 @c (generate-documentation) than to make it below and have to deal with
21660 @c the churn as Prosody updates.
21662 Available @code{prosody-configuration} fields are:
21664 @deftypevr {@code{prosody-configuration} parameter} package prosody
21665 The Prosody package.
21668 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
21669 Location of the Prosody data storage directory. See
21670 @url{https://prosody.im/doc/configure}.
21671 Defaults to @samp{"/var/lib/prosody"}.
21674 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
21675 Additional plugin directories. They are searched in all the specified
21676 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
21677 Defaults to @samp{()}.
21680 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
21681 Every virtual host and component needs a certificate so that clients and
21682 servers can securely verify its identity. Prosody will automatically load
21683 certificates/keys from the directory specified here.
21684 Defaults to @samp{"/etc/prosody/certs"}.
21687 @deftypevr {@code{prosody-configuration} parameter} string-list admins
21688 This is a list of accounts that are admins for the server. Note that you
21689 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
21690 @url{https://prosody.im/doc/creating_accounts}.
21691 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
21692 Defaults to @samp{()}.
21695 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
21696 Enable use of libevent for better performance under high load. See
21697 @url{https://prosody.im/doc/libevent}.
21698 Defaults to @samp{#f}.
21701 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
21702 This is the list of modules Prosody will load on startup. It looks for
21703 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
21704 Documentation on modules can be found at:
21705 @url{https://prosody.im/doc/modules}.
21706 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
21709 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
21710 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
21711 should you want to disable them then add them to this list.
21712 Defaults to @samp{()}.
21715 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
21716 Path to a text file where the shared groups are defined. If this path is
21717 empty then @samp{mod_groups} does nothing. See
21718 @url{https://prosody.im/doc/modules/mod_groups}.
21719 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
21722 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
21723 Disable account creation by default, for security. See
21724 @url{https://prosody.im/doc/creating_accounts}.
21725 Defaults to @samp{#f}.
21728 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
21729 These are the SSL/TLS-related settings. Most of them are disabled so to
21730 use Prosody's defaults. If you do not completely understand these options, do
21731 not add them to your config, it is easy to lower the security of your server
21732 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
21734 Available @code{ssl-configuration} fields are:
21736 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
21737 This determines what handshake to use.
21740 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
21741 Path to your private key file.
21744 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
21745 Path to your certificate file.
21748 @deftypevr {@code{ssl-configuration} parameter} file-object capath
21749 Path to directory containing root certificates that you wish Prosody to
21750 trust when verifying the certificates of remote servers.
21751 Defaults to @samp{"/etc/ssl/certs"}.
21754 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
21755 Path to a file containing root certificates that you wish Prosody to trust.
21756 Similar to @code{capath} but with all certificates concatenated together.
21759 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
21760 A list of verification options (these mostly map to OpenSSL's
21761 @code{set_verify()} flags).
21764 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
21765 A list of general options relating to SSL/TLS@. These map to OpenSSL's
21766 @code{set_options()}. For a full list of options available in LuaSec, see the
21770 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
21771 How long a chain of certificate authorities to check when looking for a
21772 trusted root certificate.
21775 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
21776 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
21777 clients, and in what order.
21780 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
21781 A path to a file containing parameters for Diffie-Hellman key exchange. You
21782 can create such a file with:
21783 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
21786 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
21787 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
21788 @samp{"secp384r1"}.
21791 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
21792 A list of ``extra'' verification options.
21795 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
21796 Password for encrypted private keys.
21801 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
21802 Whether to force all client-to-server connections to be encrypted or not.
21803 See @url{https://prosody.im/doc/modules/mod_tls}.
21804 Defaults to @samp{#f}.
21807 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
21808 Set of mechanisms that will never be offered. See
21809 @url{https://prosody.im/doc/modules/mod_saslauth}.
21810 Defaults to @samp{("DIGEST-MD5")}.
21813 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
21814 Whether to force all server-to-server connections to be encrypted or not.
21815 See @url{https://prosody.im/doc/modules/mod_tls}.
21816 Defaults to @samp{#f}.
21819 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
21820 Whether to require encryption and certificate authentication. This
21821 provides ideal security, but requires servers you communicate with to support
21822 encryption AND present valid, trusted certificates. See
21823 @url{https://prosody.im/doc/s2s#security}.
21824 Defaults to @samp{#f}.
21827 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
21828 Many servers don't support encryption or have invalid or self-signed
21829 certificates. You can list domains here that will not be required to
21830 authenticate using certificates. They will be authenticated using DNS@. See
21831 @url{https://prosody.im/doc/s2s#security}.
21832 Defaults to @samp{()}.
21835 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
21836 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
21837 valid certificates for some domains by specifying a list here. See
21838 @url{https://prosody.im/doc/s2s#security}.
21839 Defaults to @samp{()}.
21842 @deftypevr {@code{prosody-configuration} parameter} string authentication
21843 Select the authentication backend to use. The default provider stores
21844 passwords in plaintext and uses Prosody's configured data storage to store the
21845 authentication data. If you do not trust your server please see
21846 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
21847 about using the hashed backend. See also
21848 @url{https://prosody.im/doc/authentication}
21849 Defaults to @samp{"internal_plain"}.
21852 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
21853 Set logging options. Advanced logging configuration is not yet supported
21854 by the Prosody service. See @url{https://prosody.im/doc/logging}.
21855 Defaults to @samp{"*syslog"}.
21858 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
21859 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
21860 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
21863 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
21864 Maximum allowed size of the HTTP body (in bytes).
21867 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
21868 Some modules expose their own URL in various ways. This URL is built
21869 from the protocol, host and port used. If Prosody sits behind a proxy, the
21870 public URL will be @code{http-external-url} instead. See
21871 @url{https://prosody.im/doc/http#external_url}.
21874 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
21875 A host in Prosody is a domain on which user accounts can be created. For
21876 example if you want your users to have addresses like
21877 @samp{"john.smith@@example.com"} then you need to add a host
21878 @samp{"example.com"}. All options in this list will apply only to this host.
21880 Note: the name @emph{virtual} host is used in configuration to avoid confusion with
21881 the actual physical host that Prosody is installed on. A single Prosody
21882 instance can serve many domains, each one defined as a VirtualHost entry in
21883 Prosody's configuration. Conversely a server that hosts a single domain would
21884 have just one VirtualHost entry.
21886 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
21888 Available @code{virtualhost-configuration} fields are:
21890 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:
21891 @deftypevr {@code{virtualhost-configuration} parameter} string domain
21892 Domain you wish Prosody to serve.
21897 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
21898 Components are extra services on a server which are available to clients,
21899 usually on a subdomain of the main server (such as
21900 @samp{"mycomponent.example.com"}). Example components might be chatroom
21901 servers, user directories, or gateways to other protocols.
21903 Internal components are implemented with Prosody-specific plugins. To add an
21904 internal component, you simply fill the hostname field, and the plugin you wish
21905 to use for the component.
21907 See @url{https://prosody.im/doc/components}.
21908 Defaults to @samp{()}.
21910 Available @code{int-component-configuration} fields are:
21912 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:
21913 @deftypevr {@code{int-component-configuration} parameter} string hostname
21914 Hostname of the component.
21917 @deftypevr {@code{int-component-configuration} parameter} string plugin
21918 Plugin you wish to use for the component.
21921 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
21922 Multi-user chat (MUC) is Prosody's module for allowing you to create
21923 hosted chatrooms/conferences for XMPP users.
21925 General information on setting up and using multi-user chatrooms can be found
21926 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
21927 which you should read if you are new to XMPP chatrooms.
21929 See also @url{https://prosody.im/doc/modules/mod_muc}.
21931 Available @code{mod-muc-configuration} fields are:
21933 @deftypevr {@code{mod-muc-configuration} parameter} string name
21934 The name to return in service discovery responses.
21935 Defaults to @samp{"Prosody Chatrooms"}.
21938 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
21939 If @samp{#t}, this will only allow admins to create new chatrooms.
21940 Otherwise anyone can create a room. The value @samp{"local"} restricts room
21941 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
21942 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
21943 restricts to service administrators only.
21944 Defaults to @samp{#f}.
21947 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
21948 Maximum number of history messages that will be sent to the member that has
21949 just joined the room.
21950 Defaults to @samp{20}.
21957 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
21958 External components use XEP-0114, which most standalone components
21959 support. To add an external component, you simply fill the hostname field. See
21960 @url{https://prosody.im/doc/components}.
21961 Defaults to @samp{()}.
21963 Available @code{ext-component-configuration} fields are:
21965 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:
21966 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
21967 Password which the component will use to log in.
21970 @deftypevr {@code{ext-component-configuration} parameter} string hostname
21971 Hostname of the component.
21976 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
21977 Port(s) Prosody listens on for component connections.
21978 Defaults to @samp{(5347)}.
21981 @deftypevr {@code{prosody-configuration} parameter} string component-interface
21982 Interface Prosody listens on for component connections.
21983 Defaults to @samp{"127.0.0.1"}.
21986 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
21987 Raw content that will be added to the configuration file.
21990 It could be that you just want to get a @code{prosody.cfg.lua}
21991 up and running. In that case, you can pass an
21992 @code{opaque-prosody-configuration} record as the value of
21993 @code{prosody-service-type}. As its name indicates, an opaque configuration
21994 does not have easy reflective capabilities.
21995 Available @code{opaque-prosody-configuration} fields are:
21997 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
21998 The prosody package.
22001 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
22002 The contents of the @code{prosody.cfg.lua} to use.
22005 For example, if your @code{prosody.cfg.lua} is just the empty
22006 string, you could instantiate a prosody service like this:
22009 (service prosody-service-type
22010 (opaque-prosody-configuration
22011 (prosody.cfg.lua "")))
22014 @c end of Prosody auto-generated documentation
22016 @subsubheading BitlBee Service
22018 @cindex IRC (Internet Relay Chat)
22019 @cindex IRC gateway
22020 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
22021 interface to a variety of messaging protocols such as XMPP.
22023 @defvr {Scheme Variable} bitlbee-service-type
22024 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
22025 gateway daemon. Its value is a @code{bitlbee-configuration} (see
22028 To have BitlBee listen on port 6667 on localhost, add this line to your
22032 (service bitlbee-service-type)
22036 @deftp {Data Type} bitlbee-configuration
22037 This is the configuration for BitlBee, with the following fields:
22040 @item @code{interface} (default: @code{"127.0.0.1"})
22041 @itemx @code{port} (default: @code{6667})
22042 Listen on the network interface corresponding to the IP address
22043 specified in @var{interface}, on @var{port}.
22045 When @var{interface} is @code{127.0.0.1}, only local clients can
22046 connect; when it is @code{0.0.0.0}, connections can come from any
22047 networking interface.
22049 @item @code{bitlbee} (default: @code{bitlbee})
22050 The BitlBee package to use.
22052 @item @code{plugins} (default: @code{'()})
22053 List of plugin packages to use---e.g., @code{bitlbee-discord}.
22055 @item @code{extra-settings} (default: @code{""})
22056 Configuration snippet added as-is to the BitlBee configuration file.
22060 @subsubheading Quassel Service
22062 @cindex IRC (Internet Relay Chat)
22063 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
22064 meaning that one or more clients can attach to and detach from the
22067 @defvr {Scheme Variable} quassel-service-type
22068 This is the service type for the @url{https://quassel-irc.org/,Quassel}
22069 IRC backend daemon. Its value is a @code{quassel-configuration}
22073 @deftp {Data Type} quassel-configuration
22074 This is the configuration for Quassel, with the following fields:
22077 @item @code{quassel} (default: @code{quassel})
22078 The Quassel package to use.
22080 @item @code{interface} (default: @code{"::,0.0.0.0"})
22081 @item @code{port} (default: @code{4242})
22082 Listen on the network interface(s) corresponding to the IPv4 or IPv6
22083 interfaces specified in the comma delimited @var{interface}, on
22086 @item @code{loglevel} (default: @code{"Info"})
22087 The level of logging desired. Accepted values are Debug, Info, Warning
22092 @node Telephony Services
22093 @subsection Telephony Services
22095 @cindex Murmur (VoIP server)
22096 @cindex VoIP server
22097 This section describes how to set up and run a Murmur server. Murmur is
22098 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
22101 @deftp {Data Type} murmur-configuration
22102 The service type for the Murmur server. An example configuration can
22106 (service murmur-service-type
22107 (murmur-configuration
22109 "Welcome to this Mumble server running on Guix!")
22110 (cert-required? #t) ;disallow text password logins
22111 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
22112 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
22115 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
22116 password with the command that is printed during the activation phase.
22118 It is recommended to register a normal Mumble user account
22119 and grant it admin or moderator rights.
22120 You can use the @code{mumble} client to
22121 login as new normal user, register yourself, and log out.
22122 For the next step login with the name @code{SuperUser} use
22123 the @code{SuperUser} password that you set previously,
22124 and grant your newly registered mumble user administrator or moderator
22125 rights and create some channels.
22127 Available @code{murmur-configuration} fields are:
22130 @item @code{package} (default: @code{mumble})
22131 Package that contains @code{bin/murmurd}.
22133 @item @code{user} (default: @code{"murmur"})
22134 User who will run the Murmur server.
22136 @item @code{group} (default: @code{"murmur"})
22137 Group of the user who will run the murmur server.
22139 @item @code{port} (default: @code{64738})
22140 Port on which the server will listen.
22142 @item @code{welcome-text} (default: @code{""})
22143 Welcome text sent to clients when they connect.
22145 @item @code{server-password} (default: @code{""})
22146 Password the clients have to enter in order to connect.
22148 @item @code{max-users} (default: @code{100})
22149 Maximum of users that can be connected to the server at once.
22151 @item @code{max-user-bandwidth} (default: @code{#f})
22152 Maximum voice traffic a user can send per second.
22154 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
22155 File name of the sqlite database.
22156 The service's user will become the owner of the directory.
22158 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
22159 File name of the log file.
22160 The service's user will become the owner of the directory.
22162 @item @code{autoban-attempts} (default: @code{10})
22163 Maximum number of logins a user can make in @code{autoban-timeframe}
22164 without getting auto banned for @code{autoban-time}.
22166 @item @code{autoban-timeframe} (default: @code{120})
22167 Timeframe for autoban in seconds.
22169 @item @code{autoban-time} (default: @code{300})
22170 Amount of time in seconds for which a client gets banned
22171 when violating the autoban limits.
22173 @item @code{opus-threshold} (default: @code{100})
22174 Percentage of clients that need to support opus
22175 before switching over to opus audio codec.
22177 @item @code{channel-nesting-limit} (default: @code{10})
22178 How deep channels can be nested at maximum.
22180 @item @code{channelname-regex} (default: @code{#f})
22181 A string in form of a Qt regular expression that channel names must conform to.
22183 @item @code{username-regex} (default: @code{#f})
22184 A string in form of a Qt regular expression that user names must conform to.
22186 @item @code{text-message-length} (default: @code{5000})
22187 Maximum size in bytes that a user can send in one text chat message.
22189 @item @code{image-message-length} (default: @code{(* 128 1024)})
22190 Maximum size in bytes that a user can send in one image message.
22192 @item @code{cert-required?} (default: @code{#f})
22193 If it is set to @code{#t} clients that use weak password authentication
22194 will not be accepted. Users must have completed the certificate wizard to join.
22196 @item @code{remember-channel?} (default: @code{#f})
22197 Should murmur remember the last channel each user was in when they disconnected
22198 and put them into the remembered channel when they rejoin.
22200 @item @code{allow-html?} (default: @code{#f})
22201 Should html be allowed in text messages, user comments, and channel descriptions.
22203 @item @code{allow-ping?} (default: @code{#f})
22204 Setting to true exposes the current user count, the maximum user count, and
22205 the server's maximum bandwidth per client to unauthenticated users. In the
22206 Mumble client, this information is shown in the Connect dialog.
22208 Disabling this setting will prevent public listing of the server.
22210 @item @code{bonjour?} (default: @code{#f})
22211 Should the server advertise itself in the local network through the bonjour protocol.
22213 @item @code{send-version?} (default: @code{#f})
22214 Should the murmur server version be exposed in ping requests.
22216 @item @code{log-days} (default: @code{31})
22217 Murmur also stores logs in the database, which are accessible via RPC.
22218 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
22219 or -1 to disable logging to the database.
22221 @item @code{obfuscate-ips?} (default: @code{#t})
22222 Should logged ips be obfuscated to protect the privacy of users.
22224 @item @code{ssl-cert} (default: @code{#f})
22225 File name of the SSL/TLS certificate used for encrypted connections.
22228 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
22230 @item @code{ssl-key} (default: @code{#f})
22231 Filepath to the ssl private key used for encrypted connections.
22233 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
22236 @item @code{ssl-dh-params} (default: @code{#f})
22237 File name of a PEM-encoded file with Diffie-Hellman parameters
22238 for the SSL/TLS encryption. Alternatively you set it to
22239 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
22240 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
22242 @item @code{ssl-ciphers} (default: @code{#f})
22243 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
22246 This option is specified using
22247 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
22248 OpenSSL cipher list notation}.
22250 It is recommended that you try your cipher string using 'openssl ciphers <string>'
22251 before setting it here, to get a feel for which cipher suites you will get.
22252 After setting this option, it is recommend that you inspect your Murmur log
22253 to ensure that Murmur is using the cipher suites that you expected it to.
22255 Note: Changing this option may impact the backwards compatibility of your
22256 Murmur server, and can remove the ability for older Mumble clients to be able
22259 @item @code{public-registration} (default: @code{#f})
22260 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
22262 You can optionally register your server in the public server list that the
22263 @code{mumble} client shows on startup.
22264 You cannot register your server if you have set a @code{server-password},
22265 or set @code{allow-ping} to @code{#f}.
22267 It might take a few hours until it shows up in the public list.
22269 @item @code{file} (default: @code{#f})
22270 Optional alternative override for this configuration.
22274 @deftp {Data Type} murmur-public-registration-configuration
22275 Configuration for public registration of a murmur service.
22279 This is a display name for your server. Not to be confused with the hostname.
22281 @item @code{password}
22282 A password to identify your registration.
22283 Subsequent updates will need the same password. Don't lose your password.
22286 This should be a @code{http://} or @code{https://} link to your web
22289 @item @code{hostname} (default: @code{#f})
22290 By default your server will be listed by its IP address.
22291 If it is set your server will be linked by this host name instead.
22297 @node File-Sharing Services
22298 @subsection File-Sharing Services
22300 The @code{(gnu services file-sharing)} module provides services that
22301 assist with transferring files over peer-to-peer file-sharing networks.
22303 @subsubheading Transmission Daemon Service
22305 @uref{https://transmissionbt.com/, Transmission} is a flexible
22306 BitTorrent client that offers a variety of graphical and command-line
22307 interfaces. A @code{transmission-daemon-service-type} service provides
22308 Transmission's headless variant, @command{transmission-daemon}, as a
22309 system service, allowing users to share files via BitTorrent even when
22310 they are not logged in.
22312 @deffn {Scheme Variable} transmission-daemon-service-type
22313 The service type for the Transmission Daemon BitTorrent client. Its
22314 value must be a @code{transmission-daemon-configuration} object as in
22318 (service transmission-daemon-service-type
22319 (transmission-daemon-configuration
22320 ;; Restrict access to the RPC ("control") interface
22321 (rpc-authentication-required? #t)
22322 (rpc-username "transmission")
22324 (transmission-password-hash
22325 "transmission" ; desired password
22326 "uKd1uMs9")) ; arbitrary salt value
22328 ;; Accept requests from this and other hosts on the
22330 (rpc-whitelist-enabled? #t)
22331 (rpc-whitelist '("::1" "127.0.0.1" "192.168.0.*"))
22333 ;; Limit bandwidth use during work hours
22334 (alt-speed-down (* 1024 2)) ; 2 MB/s
22335 (alt-speed-up 512) ; 512 kB/s
22337 (alt-speed-time-enabled? #t)
22338 (alt-speed-time-day 'weekdays)
22339 (alt-speed-time-begin
22340 (+ (* 60 8) 30)) ; 8:30 am
22341 (alt-speed-time-end
22342 (+ (* 60 (+ 12 5)) 30)))) ; 5:30 pm
22346 Once the service is started, users can interact with the daemon through
22347 its Web interface (at @code{http://localhost:9091/}) or by using the
22348 @command{transmission-remote} command-line tool, available in the
22349 @code{transmission} package. (Emacs users may want to also consider the
22350 @code{emacs-transmission} package.) Both communicate with the daemon
22351 through its remote procedure call (RPC) interface, which by default is
22352 available to all users on the system; you may wish to change this by
22353 assigning values to the @code{rpc-authentication-required?},
22354 @code{rpc-username} and @code{rpc-password} settings, as shown in the
22355 example above and documented further below.
22357 The value for @code{rpc-password} must be a password hash of the type
22358 generated and used by Transmission clients. This can be copied verbatim
22359 from an existing @file{settings.json} file, if another Transmission
22360 client is already being used. Otherwise, the
22361 @code{transmission-password-hash} and @code{transmission-random-salt}
22362 procedures provided by this module can be used to obtain a suitable hash
22365 @deffn {Scheme Procedure} transmission-password-hash @var{password} @var{salt}
22366 Returns a string containing the result of hashing @var{password}
22367 together with @var{salt}, in the format recognized by Transmission
22368 clients for their @code{rpc-password} configuration setting.
22370 @var{salt} must be an eight-character string. The
22371 @code{transmission-random-salt} procedure can be used to generate a
22372 suitable salt value at random.
22375 @deffn {Scheme Procedure} transmission-random-salt
22376 Returns a string containing a random, eight-character salt value of the
22377 type generated and used by Transmission clients, suitable for passing to
22378 the @code{transmission-password-hash} procedure.
22381 These procedures are accessible from within a Guile REPL started with
22382 the @command{guix repl} command (@pxref{Invoking guix repl}). This is
22383 useful for obtaining a random salt value to provide as the second
22384 parameter to `transmission-password-hash`, as in this example session:
22388 scheme@@(guix-user)> ,use (gnu services file-sharing)
22389 scheme@@(guix-user)> (transmission-random-salt)
22393 Alternatively, a complete password hash can generated in a single step:
22396 scheme@@(guix-user)> (transmission-password-hash "transmission"
22397 (transmission-random-salt))
22398 $2 = "@{c8bbc6d1740cd8dc819a6e25563b67812c1c19c9VtFPfdsX"
22401 The resulting string can be used as-is for the value of
22402 @code{rpc-password}, allowing the password to be kept hidden even in the
22403 operating-system configuration.
22405 Torrent files downloaded by the daemon are directly accessible only to
22406 users in the ``transmission'' user group, who receive read-only access
22407 to the directory specified by the @code{download-dir} configuration
22408 setting (and also the directory specified by @code{incomplete-dir}, if
22409 @code{incomplete-dir-enabled?} is @code{#t}). Downloaded files can be
22410 moved to another directory or deleted altogether using
22411 @command{transmission-remote} with its @code{--move} and
22412 @code{--remove-and-delete} options.
22414 If the @code{watch-dir-enabled?} setting is set to @code{#t}, users in
22415 the ``transmission'' group are able also to place @file{.torrent} files
22416 in the directory specified by @code{watch-dir} to have the corresponding
22417 torrents added by the daemon. (The @code{trash-original-torrent-files?}
22418 setting controls whether the daemon deletes these files after processing
22421 Some of the daemon's configuration settings can be changed temporarily
22422 by @command{transmission-remote} and similar tools. To undo these
22423 changes, use the service's @code{reload} action to have the daemon
22424 reload its settings from disk:
22427 # herd reload transmission-daemon
22430 The full set of available configuration settings is defined by the
22431 @code{transmission-daemon-configuration} data type.
22433 @deftp {Data Type} transmission-daemon-configuration
22434 The data type representing configuration settings for Transmission
22435 Daemon. These correspond directly to the settings recognized by
22436 Transmission clients in their @file{settings.json} file.
22439 @c The following documentation was initially generated by
22440 @c (generate-transmission-daemon-documentation) in (gnu services
22441 @c file-sharing). Manually maintained documentation is better, so we
22442 @c shouldn't hesitate to edit below as needed. However if the change
22443 @c you want to make to this documentation can be done in an automated
22444 @c way, it's probably easier to change (generate-documentation) than to
22445 @c make it below and have to deal with the churn as Transmission Daemon
22448 @c %start of fragment
22450 Available @code{transmission-daemon-configuration} fields are:
22452 @deftypevr {@code{transmission-daemon-configuration} parameter} package transmission
22453 The Transmission package to use.
22457 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer stop-wait-period
22458 The period, in seconds, to wait when stopping the service for
22459 @command{transmission-daemon} to exit before killing its process. This
22460 allows the daemon time to complete its housekeeping and send a final
22461 update to trackers as it shuts down. On slow hosts, or hosts with a
22462 slow network connection, this value may need to be increased.
22464 Defaults to @samp{10}.
22468 @deftypevr {@code{transmission-daemon-configuration} parameter} string download-dir
22469 The directory to which torrent files are downloaded.
22471 Defaults to @samp{"/var/lib/transmission-daemon/downloads"}.
22475 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean incomplete-dir-enabled?
22476 If @code{#t}, files will be held in @code{incomplete-dir} while their
22477 torrent is being downloaded, then moved to @code{download-dir} once the
22478 torrent is complete. Otherwise, files for all torrents (including those
22479 still being downloaded) will be placed in @code{download-dir}.
22481 Defaults to @samp{#f}.
22485 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string incomplete-dir
22486 The directory in which files from incompletely downloaded torrents will
22487 be held when @code{incomplete-dir-enabled?} is @code{#t}.
22489 Defaults to @samp{disabled}.
22493 @deftypevr {@code{transmission-daemon-configuration} parameter} umask umask
22494 The file mode creation mask used for downloaded files. (See the
22495 @command{umask} man page for more information.)
22497 Defaults to @samp{18}.
22501 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rename-partial-files?
22502 When @code{#t}, ``.part'' is appended to the name of partially
22505 Defaults to @samp{#t}.
22509 @deftypevr {@code{transmission-daemon-configuration} parameter} preallocation-mode preallocation
22510 The mode by which space should be preallocated for downloaded files, one
22511 of @code{none}, @code{fast} (or @code{sparse}) and @code{full}.
22512 Specifying @code{full} will minimize disk fragmentation at a cost to
22513 file-creation speed.
22515 Defaults to @samp{fast}.
22519 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean watch-dir-enabled?
22520 If @code{#t}, the directory specified by @code{watch-dir} will be
22521 watched for new @file{.torrent} files and the torrents they describe
22522 added automatically (and the original files removed, if
22523 @code{trash-original-torrent-files?} is @code{#t}).
22525 Defaults to @samp{#f}.
22529 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string watch-dir
22530 The directory to be watched for @file{.torrent} files indicating new
22531 torrents to be added, when @code{watch-dir-enabled} is @code{#t}.
22533 Defaults to @samp{disabled}.
22537 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean trash-original-torrent-files?
22538 When @code{#t}, @file{.torrent} files will be deleted from the watch
22539 directory once their torrent has been added (see
22540 @code{watch-directory-enabled?}).
22542 Defaults to @samp{#f}.
22546 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-down-enabled?
22547 When @code{#t}, the daemon's download speed will be limited to the rate
22548 specified by @code{speed-limit-down}.
22550 Defaults to @samp{#f}.
22554 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-down
22555 The default global-maximum download speed, in kilobytes per second.
22557 Defaults to @samp{100}.
22561 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-up-enabled?
22562 When @code{#t}, the daemon's upload speed will be limited to the rate
22563 specified by @code{speed-limit-up}.
22565 Defaults to @samp{#f}.
22569 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-up
22570 The default global-maximum upload speed, in kilobytes per second.
22572 Defaults to @samp{100}.
22576 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-enabled?
22577 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
22578 @code{alt-speed-up} are used (in place of @code{speed-limit-down} and
22579 @code{speed-limit-up}, if they are enabled) to constrain the daemon's
22580 bandwidth usage. This can be scheduled to occur automatically at
22581 certain times during the week; see @code{alt-speed-time-enabled?}.
22583 Defaults to @samp{#f}.
22587 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-down
22588 The alternate global-maximum download speed, in kilobytes per second.
22590 Defaults to @samp{50}.
22594 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-up
22595 The alternate global-maximum upload speed, in kilobytes per second.
22597 Defaults to @samp{50}.
22601 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-time-enabled?
22602 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
22603 @code{alt-speed-up} will be enabled automatically during the periods
22604 specified by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
22605 @code{alt-time-speed-end}.
22607 Defaults to @samp{#f}.
22611 @deftypevr {@code{transmission-daemon-configuration} parameter} day-list alt-speed-time-day
22612 The days of the week on which the alternate-speed schedule should be
22613 used, specified either as a list of days (@code{sunday}, @code{monday},
22614 and so on) or using one of the symbols @code{weekdays}, @code{weekends}
22617 Defaults to @samp{all}.
22621 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-begin
22622 The time of day at which to enable the alternate speed limits, expressed
22623 as a number of minutes since midnight.
22625 Defaults to @samp{540}.
22629 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-end
22630 The time of day at which to disable the alternate speed limits,
22631 expressed as a number of minutes since midnight.
22633 Defaults to @samp{1020}.
22637 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv4
22638 The IP address at which to listen for peer connections, or ``0.0.0.0''
22639 to listen at all available IP addresses.
22641 Defaults to @samp{"0.0.0.0"}.
22645 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv6
22646 The IPv6 address at which to listen for peer connections, or ``::'' to
22647 listen at all available IPv6 addresses.
22649 Defaults to @samp{"::"}.
22653 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean peer-port-random-on-start?
22654 If @code{#t}, when the daemon starts it will select a port at random on
22655 which to listen for peer connections, from the range specified
22656 (inclusively) by @code{peer-port-random-low} and
22657 @code{peer-port-random-high}. Otherwise, it listens on the port
22658 specified by @code{peer-port}.
22660 Defaults to @samp{#f}.
22664 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-low
22665 The lowest selectable port number when @code{peer-port-random-on-start?}
22668 Defaults to @samp{49152}.
22672 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-high
22673 The highest selectable port number when @code{peer-port-random-on-start}
22676 Defaults to @samp{65535}.
22680 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port
22681 The port on which to listen for peer connections when
22682 @code{peer-port-random-on-start?} is @code{#f}.
22684 Defaults to @samp{51413}.
22688 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean port-forwarding-enabled?
22689 If @code{#t}, the daemon will attempt to configure port-forwarding on an
22690 upstream gateway automatically using @acronym{UPnP} and
22693 Defaults to @samp{#t}.
22697 @deftypevr {@code{transmission-daemon-configuration} parameter} encryption-mode encryption
22698 The encryption preference for peer connections, one of
22699 @code{prefer-unencrypted-connections},
22700 @code{prefer-encrypted-connections} or
22701 @code{require-encrypted-connections}.
22703 Defaults to @samp{prefer-encrypted-connections}.
22707 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string peer-congestion-algorithm
22708 The TCP congestion-control algorithm to use for peer connections,
22709 specified using a string recognized by the operating system in calls to
22710 @code{setsockopt} (or set to @code{disabled}, in which case the
22711 operating-system default is used).
22713 Note that on GNU/Linux systems, the kernel must be configured to allow
22714 processes to use a congestion-control algorithm not in the default set;
22715 otherwise, it will deny these requests with ``Operation not permitted''.
22716 To see which algorithms are available on your system and which are
22717 currently permitted for use, look at the contents of the files
22718 @file{tcp_available_congestion_control} and
22719 @file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
22722 As an example, to have Transmission Daemon use
22723 @uref{http://www-ece.rice.edu/networks/TCP-LP/,the TCP Low Priority
22724 congestion-control algorithm}, you'll need to modify your kernel
22725 configuration to build in support for the algorithm, then update your
22726 operating-system configuration to allow its use by adding a
22727 @code{sysctl-service-type} service (or updating the existing one's
22728 configuration) with lines like the following:
22731 (service sysctl-service-type
22732 (sysctl-configuration
22734 ("net.ipv4.tcp_allowed_congestion_control" .
22735 "reno cubic lp"))))
22738 The Transmission Daemon configuration can then be updated with
22741 (peer-congestion-algorithm "lp")
22744 and the system reconfigured to have the changes take effect.
22746 Defaults to @samp{disabled}.
22750 @deftypevr {@code{transmission-daemon-configuration} parameter} tcp-type-of-service peer-socket-tos
22751 The type of service to request in outgoing @acronym{TCP} packets, one of
22752 @code{default}, @code{low-cost}, @code{throughput}, @code{low-delay} and
22753 @code{reliability}.
22755 Defaults to @samp{default}.
22759 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-global
22760 The global limit on the number of connected peers.
22762 Defaults to @samp{200}.
22766 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-per-torrent
22767 The per-torrent limit on the number of connected peers.
22769 Defaults to @samp{50}.
22773 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer upload-slots-per-torrent
22774 The maximum number of peers to which the daemon will upload data
22775 simultaneously for each torrent.
22777 Defaults to @samp{14}.
22781 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-id-ttl-hours
22782 The maximum lifespan, in hours, of the peer ID associated with each
22783 public torrent before it is regenerated.
22785 Defaults to @samp{6}.
22789 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean blocklist-enabled?
22790 When @code{#t}, the daemon will ignore peers mentioned in the blocklist
22791 it has most recently downloaded from @code{blocklist-url}.
22793 Defaults to @samp{#f}.
22797 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string blocklist-url
22798 The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
22799 @file{.dat} format) to be periodically downloaded and applied when
22800 @code{blocklist-enabled?} is @code{#t}.
22802 Defaults to @samp{disabled}.
22806 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean download-queue-enabled?
22807 If @code{#t}, the daemon will be limited to downloading at most
22808 @code{download-queue-size} non-stalled torrents simultaneously.
22810 Defaults to @samp{#t}.
22814 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer download-queue-size
22815 The size of the daemon's download queue, which limits the number of
22816 non-stalled torrents it will download at any one time when
22817 @code{download-queue-enabled?} is @code{#t}.
22819 Defaults to @samp{5}.
22823 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean seed-queue-enabled?
22824 If @code{#t}, the daemon will be limited to seeding at most
22825 @code{seed-queue-size} non-stalled torrents simultaneously.
22827 Defaults to @samp{#f}.
22831 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer seed-queue-size
22832 The size of the daemon's seed queue, which limits the number of
22833 non-stalled torrents it will seed at any one time when
22834 @code{seed-queue-enabled?} is @code{#t}.
22836 Defaults to @samp{10}.
22840 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean queue-stalled-enabled?
22841 When @code{#t}, the daemon will consider torrents for which it has not
22842 shared data in the past @code{queue-stalled-minutes} minutes to be
22843 stalled and not count them against its @code{download-queue-size} and
22844 @code{seed-queue-size} limits.
22846 Defaults to @samp{#t}.
22850 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer queue-stalled-minutes
22851 The maximum period, in minutes, a torrent may be idle before it is
22852 considered to be stalled, when @code{queue-stalled-enabled?} is
22855 Defaults to @samp{30}.
22859 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean ratio-limit-enabled?
22860 When @code{#t}, a torrent being seeded will automatically be paused once
22861 it reaches the ratio specified by @code{ratio-limit}.
22863 Defaults to @samp{#f}.
22867 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-rational ratio-limit
22868 The ratio at which a torrent being seeded will be paused, when
22869 @code{ratio-limit-enabled?} is @code{#t}.
22871 Defaults to @samp{2.0}.
22875 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean idle-seeding-limit-enabled?
22876 When @code{#t}, a torrent being seeded will automatically be paused once
22877 it has been idle for @code{idle-seeding-limit} minutes.
22879 Defaults to @samp{#f}.
22883 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer idle-seeding-limit
22884 The maximum period, in minutes, a torrent being seeded may be idle
22885 before it is paused, when @code{idle-seeding-limit-enabled?} is
22888 Defaults to @samp{30}.
22892 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean dht-enabled?
22893 Enable @uref{http://bittorrent.org/beps/bep_0005.html,the distributed
22894 hash table (@acronym{DHT}) protocol}, which supports the use of
22895 trackerless torrents.
22897 Defaults to @samp{#t}.
22901 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean lpd-enabled?
22902 Enable @uref{https://en.wikipedia.org/wiki/Local_Peer_Discovery,local
22903 peer discovery} (@acronym{LPD}), which allows the discovery of peers on
22904 the local network and may reduce the amount of data sent over the public
22907 Defaults to @samp{#f}.
22911 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean pex-enabled?
22912 Enable @uref{https://en.wikipedia.org/wiki/Peer_exchange,peer exchange}
22913 (@acronym{PEX}), which reduces the daemon's reliance on external
22914 trackers and may improve its performance.
22916 Defaults to @samp{#t}.
22920 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean utp-enabled?
22921 Enable @uref{http://bittorrent.org/beps/bep_0029.html,the micro
22922 transport protocol} (@acronym{uTP}), which aims to reduce the impact of
22923 BitTorrent traffic on other users of the local network while maintaining
22924 full utilization of the available bandwidth.
22926 Defaults to @samp{#t}.
22930 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-enabled?
22931 If @code{#t}, enable the remote procedure call (@acronym{RPC})
22932 interface, which allows remote control of the daemon via its Web
22933 interface, the @command{transmission-remote} command-line client, and
22936 Defaults to @samp{#t}.
22940 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-bind-address
22941 The IP address at which to listen for @acronym{RPC} connections, or
22942 ``0.0.0.0'' to listen at all available IP addresses.
22944 Defaults to @samp{"0.0.0.0"}.
22948 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number rpc-port
22949 The port on which to listen for @acronym{RPC} connections.
22951 Defaults to @samp{9091}.
22955 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-url
22956 The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.
22958 Defaults to @samp{"/transmission/"}.
22962 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-authentication-required?
22963 When @code{#t}, clients must authenticate (see @code{rpc-username} and
22964 @code{rpc-password}) when using the @acronym{RPC} interface. Note this
22965 has the side effect of disabling host-name whitelisting (see
22966 @code{rpc-host-whitelist-enabled?}.
22968 Defaults to @samp{#f}.
22972 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string rpc-username
22973 The username required by clients to access the @acronym{RPC} interface
22974 when @code{rpc-authentication-required?} is @code{#t}.
22976 Defaults to @samp{disabled}.
22980 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-transmission-password-hash rpc-password
22981 The password required by clients to access the @acronym{RPC} interface
22982 when @code{rpc-authentication-required?} is @code{#t}. This must be
22983 specified using a password hash in the format recognized by Transmission
22984 clients, either copied from an existing @file{settings.json} file or
22985 generated using the @code{transmission-password-hash} procedure.
22987 Defaults to @samp{disabled}.
22991 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-whitelist-enabled?
22992 When @code{#t}, @acronym{RPC} requests will be accepted only when they
22993 originate from an address specified in @code{rpc-whitelist}.
22995 Defaults to @samp{#t}.
22999 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-whitelist
23000 The list of IP and IPv6 addresses from which @acronym{RPC} requests will
23001 be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards
23002 may be specified using @samp{*}.
23004 Defaults to @samp{("127.0.0.1" "::1")}.
23008 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-host-whitelist-enabled?
23009 When @code{#t}, @acronym{RPC} requests will be accepted only when they
23010 are addressed to a host named in @code{rpc-host-whitelist}. Note that
23011 requests to ``localhost'' or ``localhost.'', or to a numeric address,
23012 are always accepted regardless of these settings.
23014 Note also this functionality is disabled when
23015 @code{rpc-authentication-required?} is @code{#t}.
23017 Defaults to @samp{#t}.
23021 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-host-whitelist
23022 The list of host names recognized by the @acronym{RPC} server when
23023 @code{rpc-host-whitelist-enabled?} is @code{#t}.
23025 Defaults to @samp{()}.
23029 @deftypevr {@code{transmission-daemon-configuration} parameter} message-level message-level
23030 The minimum severity level of messages to be logged (to
23031 @file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
23032 logging), @code{error}, @code{info} and @code{debug}.
23034 Defaults to @samp{info}.
23038 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean start-added-torrents?
23039 When @code{#t}, torrents are started as soon as they are added;
23040 otherwise, they are added in ``paused'' state.
23042 Defaults to @samp{#t}.
23046 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean script-torrent-done-enabled?
23047 When @code{#t}, the script specified by
23048 @code{script-torrent-done-filename} will be invoked each time a torrent
23051 Defaults to @samp{#f}.
23055 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-file-object script-torrent-done-filename
23056 A file name or file-like object specifying a script to run each time a
23057 torrent completes, when @code{script-torrent-done-enabled?} is
23060 Defaults to @samp{disabled}.
23064 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean scrape-paused-torrents-enabled?
23065 When @code{#t}, the daemon will scrape trackers for a torrent even when
23066 the torrent is paused.
23068 Defaults to @samp{#t}.
23072 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer cache-size-mb
23073 The amount of memory, in megabytes, to allocate for the daemon's
23074 in-memory cache. A larger value may increase performance by reducing
23075 the frequency of disk I/O.
23077 Defaults to @samp{4}.
23081 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean prefetch-enabled?
23082 When @code{#t}, the daemon will try to improve I/O performance by
23083 hinting to the operating system which data is likely to be read next
23084 from disk to satisfy requests from peers.
23086 Defaults to @samp{#t}.
23091 @c %end of fragment
23095 @node Monitoring Services
23096 @subsection Monitoring Services
23098 @subsubheading Tailon Service
23100 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
23101 viewing and searching log files.
23103 The following example will configure the service with default values.
23104 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
23107 (service tailon-service-type)
23110 The following example customises more of the Tailon configuration,
23111 adding @command{sed} to the list of allowed commands.
23114 (service tailon-service-type
23115 (tailon-configuration
23117 (tailon-configuration-file
23118 (allowed-commands '("tail" "grep" "awk" "sed"))))))
23122 @deftp {Data Type} tailon-configuration
23123 Data type representing the configuration of Tailon.
23124 This type has the following parameters:
23127 @item @code{config-file} (default: @code{(tailon-configuration-file)})
23128 The configuration file to use for Tailon. This can be set to a
23129 @dfn{tailon-configuration-file} record value, or any gexp
23130 (@pxref{G-Expressions}).
23132 For example, to instead use a local file, the @code{local-file} function
23136 (service tailon-service-type
23137 (tailon-configuration
23138 (config-file (local-file "./my-tailon.conf"))))
23141 @item @code{package} (default: @code{tailon})
23142 The tailon package to use.
23147 @deftp {Data Type} tailon-configuration-file
23148 Data type representing the configuration options for Tailon.
23149 This type has the following parameters:
23152 @item @code{files} (default: @code{(list "/var/log")})
23153 List of files to display. The list can include strings for a single file
23154 or directory, or a list, where the first item is the name of a
23155 subsection, and the remaining items are the files or directories in that
23158 @item @code{bind} (default: @code{"localhost:8080"})
23159 Address and port to which Tailon should bind on.
23161 @item @code{relative-root} (default: @code{#f})
23162 URL path to use for Tailon, set to @code{#f} to not use a path.
23164 @item @code{allow-transfers?} (default: @code{#t})
23165 Allow downloading the log files in the web interface.
23167 @item @code{follow-names?} (default: @code{#t})
23168 Allow tailing of not-yet existent files.
23170 @item @code{tail-lines} (default: @code{200})
23171 Number of lines to read initially from each file.
23173 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
23174 Commands to allow running. By default, @code{sed} is disabled.
23176 @item @code{debug?} (default: @code{#f})
23177 Set @code{debug?} to @code{#t} to show debug messages.
23179 @item @code{wrap-lines} (default: @code{#t})
23180 Initial line wrapping state in the web interface. Set to @code{#t} to
23181 initially wrap lines (the default), or to @code{#f} to initially not
23184 @item @code{http-auth} (default: @code{#f})
23185 HTTP authentication type to use. Set to @code{#f} to disable
23186 authentication (the default). Supported values are @code{"digest"} or
23189 @item @code{users} (default: @code{#f})
23190 If HTTP authentication is enabled (see @code{http-auth}), access will be
23191 restricted to the credentials provided here. To configure users, use a
23192 list of pairs, where the first element of the pair is the username, and
23193 the 2nd element of the pair is the password.
23196 (tailon-configuration-file
23197 (http-auth "basic")
23198 (users '(("user1" . "password1")
23199 ("user2" . "password2"))))
23206 @subsubheading Darkstat Service
23208 Darkstat is a packet sniffer that captures network traffic, calculates
23209 statistics about usage, and serves reports over HTTP.
23211 @defvar {Scheme Variable} darkstat-service-type
23212 This is the service type for the
23213 @uref{https://unix4lyfe.org/darkstat/, darkstat}
23214 service, its value must be a @code{darkstat-configuration} record as in
23218 (service darkstat-service-type
23219 (darkstat-configuration
23220 (interface "eno1")))
23224 @deftp {Data Type} darkstat-configuration
23225 Data type representing the configuration of @command{darkstat}.
23228 @item @code{package} (default: @code{darkstat})
23229 The darkstat package to use.
23231 @item @code{interface}
23232 Capture traffic on the specified network interface.
23234 @item @code{port} (default: @code{"667"})
23235 Bind the web interface to the specified port.
23237 @item @code{bind-address} (default: @code{"127.0.0.1"})
23238 Bind the web interface to the specified address.
23240 @item @code{base} (default: @code{"/"})
23241 Specify the path of the base URL@. This can be useful if
23242 @command{darkstat} is accessed via a reverse proxy.
23247 @subsubheading Prometheus Node Exporter Service
23249 @cindex prometheus-node-exporter
23250 The Prometheus ``node exporter'' makes hardware and operating system statistics
23251 provided by the Linux kernel available for the Prometheus monitoring system.
23252 This service should be deployed on all physical nodes and virtual machines,
23253 where monitoring these statistics is desirable.
23255 @defvar {Scheme variable} prometheus-node-exporter-service-type
23256 This is the service type for the
23257 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
23258 service, its value must be a @code{prometheus-node-exporter-configuration}.
23261 (service prometheus-node-exporter-service-type)
23265 @deftp {Data Type} prometheus-node-exporter-configuration
23266 Data type representing the configuration of @command{node_exporter}.
23269 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
23270 The prometheus-node-exporter package to use.
23272 @item @code{web-listen-address} (default: @code{":9100"})
23273 Bind the web interface to the specified address.
23275 @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
23276 This directory can be used to export metrics specific to this machine.
23277 Files containing metrics in the text format, with the filename ending in
23278 @code{.prom} should be placed in this directory.
23280 @item @code{extra-options} (default: @code{'()})
23281 Extra options to pass to the Prometheus node exporter.
23286 @subsubheading Zabbix server
23287 @cindex zabbix zabbix-server
23288 Zabbix provides monitoring metrics, among others network utilization, CPU load
23289 and disk space consumption:
23292 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
23293 @item Auto-discovery of servers and network devices and interfaces.
23294 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
23295 @item Distributed monitoring with centralized web administration.
23296 @item Native high performance agents.
23297 @item SLA, and ITIL KPI metrics on reporting.
23298 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
23299 @item Remote command execution through Zabbix proxies.
23302 @c %start of fragment
23304 Available @code{zabbix-server-configuration} fields are:
23306 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
23307 The zabbix-server package.
23311 @deftypevr {@code{zabbix-server-configuration} parameter} string user
23312 User who will run the Zabbix server.
23314 Defaults to @samp{"zabbix"}.
23318 @deftypevr {@code{zabbix-server-configuration} parameter} group group
23319 Group who will run the Zabbix server.
23321 Defaults to @samp{"zabbix"}.
23325 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
23326 Database host name.
23328 Defaults to @samp{"127.0.0.1"}.
23332 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
23335 Defaults to @samp{"zabbix"}.
23339 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
23342 Defaults to @samp{"zabbix"}.
23346 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
23347 Database password. Please, use @code{include-files} with
23348 @code{DBPassword=SECRET} inside a specified file instead.
23350 Defaults to @samp{""}.
23354 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
23357 Defaults to @samp{5432}.
23361 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
23362 Specifies where log messages are written to:
23366 @code{system} - syslog.
23369 @code{file} - file specified with @code{log-file} parameter.
23372 @code{console} - standard output.
23376 Defaults to @samp{""}.
23380 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
23381 Log file name for @code{log-type} @code{file} parameter.
23383 Defaults to @samp{"/var/log/zabbix/server.log"}.
23387 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
23390 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
23394 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
23395 The location of certificate authority (CA) files for SSL server
23396 certificate verification.
23398 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
23402 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
23403 Location of SSL client certificates.
23405 Defaults to @samp{"/etc/ssl/certs"}.
23409 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
23410 Extra options will be appended to Zabbix server configuration file.
23412 Defaults to @samp{""}.
23416 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
23417 You may include individual files or all files in a directory in the
23418 configuration file.
23420 Defaults to @samp{()}.
23424 @c %end of fragment
23426 @subsubheading Zabbix agent
23427 @cindex zabbix zabbix-agent
23429 Zabbix agent gathers information for Zabbix server.
23431 @c %start of fragment
23433 Available @code{zabbix-agent-configuration} fields are:
23435 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
23436 The zabbix-agent package.
23440 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
23441 User who will run the Zabbix agent.
23443 Defaults to @samp{"zabbix"}.
23447 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
23448 Group who will run the Zabbix agent.
23450 Defaults to @samp{"zabbix"}.
23454 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
23455 Unique, case sensitive hostname which is required for active checks and
23456 must match hostname as configured on the server.
23458 Defaults to @samp{""}.
23462 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
23463 Specifies where log messages are written to:
23467 @code{system} - syslog.
23470 @code{file} - file specified with @code{log-file} parameter.
23473 @code{console} - standard output.
23477 Defaults to @samp{""}.
23481 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
23482 Log file name for @code{log-type} @code{file} parameter.
23484 Defaults to @samp{"/var/log/zabbix/agent.log"}.
23488 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
23491 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
23495 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
23496 List of IP addresses, optionally in CIDR notation, or hostnames of
23497 Zabbix servers and Zabbix proxies. Incoming connections will be
23498 accepted only from the hosts listed here.
23500 Defaults to @samp{("127.0.0.1")}.
23504 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
23505 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
23506 proxies for active checks. If port is not specified, default port is
23507 used. If this parameter is not specified, active checks are disabled.
23509 Defaults to @samp{("127.0.0.1")}.
23513 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
23514 Extra options will be appended to Zabbix server configuration file.
23516 Defaults to @samp{""}.
23520 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
23521 You may include individual files or all files in a directory in the
23522 configuration file.
23524 Defaults to @samp{()}.
23528 @c %end of fragment
23530 @subsubheading Zabbix front-end
23531 @cindex zabbix zabbix-front-end
23533 This service provides a WEB interface to Zabbix server.
23535 @c %start of fragment
23537 Available @code{zabbix-front-end-configuration} fields are:
23539 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
23540 NGINX configuration.
23544 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
23545 Database host name.
23547 Defaults to @samp{"localhost"}.
23551 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
23554 Defaults to @samp{5432}.
23558 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
23561 Defaults to @samp{"zabbix"}.
23565 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
23568 Defaults to @samp{"zabbix"}.
23572 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
23573 Database password. Please, use @code{db-secret-file} instead.
23575 Defaults to @samp{""}.
23579 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
23580 Secret file containing the credentials for the Zabbix front-end. The value
23581 must be a local file name, not a G-expression. You are expected to create
23582 this file manually. Its contents will be copied into @file{zabbix.conf.php}
23583 as the value of @code{$DB['PASSWORD']}.
23585 Defaults to @samp{""}.
23589 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
23590 Zabbix server hostname.
23592 Defaults to @samp{"localhost"}.
23596 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
23597 Zabbix server port.
23599 Defaults to @samp{10051}.
23604 @c %end of fragment
23606 @node Kerberos Services
23607 @subsection Kerberos Services
23610 The @code{(gnu services kerberos)} module provides services relating to
23611 the authentication protocol @dfn{Kerberos}.
23613 @subsubheading Krb5 Service
23615 Programs using a Kerberos client library normally
23616 expect a configuration file in @file{/etc/krb5.conf}.
23617 This service generates such a file from a definition provided in the
23618 operating system declaration.
23619 It does not cause any daemon to be started.
23621 No ``keytab'' files are provided by this service---you must explicitly create them.
23622 This service is known to work with the MIT client library, @code{mit-krb5}.
23623 Other implementations have not been tested.
23625 @defvr {Scheme Variable} krb5-service-type
23626 A service type for Kerberos 5 clients.
23630 Here is an example of its use:
23632 (service krb5-service-type
23633 (krb5-configuration
23634 (default-realm "EXAMPLE.COM")
23635 (allow-weak-crypto? #t)
23638 (name "EXAMPLE.COM")
23639 (admin-server "groucho.example.com")
23640 (kdc "karl.example.com"))
23643 (admin-server "kerb-admin.argrx.edu")
23644 (kdc "keys.argrx.edu"))))))
23648 This example provides a Kerberos@tie{}5 client configuration which:
23650 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
23651 of which have distinct administration servers and key distribution centers;
23652 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
23653 specified by clients;
23654 @item Accepts services which only support encryption types known to be weak.
23657 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
23658 Only the most commonly used ones are described here.
23659 For a full list, and more detailed explanation of each, see the MIT
23660 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
23664 @deftp {Data Type} krb5-realm
23665 @cindex realm, kerberos
23668 This field is a string identifying the name of the realm.
23669 A common convention is to use the fully qualified DNS name of your organization,
23670 converted to upper case.
23672 @item @code{admin-server}
23673 This field is a string identifying the host where the administration server is
23677 This field is a string identifying the key distribution center
23682 @deftp {Data Type} krb5-configuration
23685 @item @code{allow-weak-crypto?} (default: @code{#f})
23686 If this flag is @code{#t} then services which only offer encryption algorithms
23687 known to be weak will be accepted.
23689 @item @code{default-realm} (default: @code{#f})
23690 This field should be a string identifying the default Kerberos
23691 realm for the client.
23692 You should set this field to the name of your Kerberos realm.
23693 If this value is @code{#f}
23694 then a realm must be specified with every Kerberos principal when invoking programs
23695 such as @command{kinit}.
23697 @item @code{realms}
23698 This should be a non-empty list of @code{krb5-realm} objects, which clients may
23700 Normally, one of them will have a @code{name} field matching the @code{default-realm}
23706 @subsubheading PAM krb5 Service
23709 The @code{pam-krb5} service allows for login authentication and password
23710 management via Kerberos.
23711 You will need this service if you want PAM enabled applications to authenticate
23712 users using Kerberos.
23714 @defvr {Scheme Variable} pam-krb5-service-type
23715 A service type for the Kerberos 5 PAM module.
23718 @deftp {Data Type} pam-krb5-configuration
23719 Data type representing the configuration of the Kerberos 5 PAM module.
23720 This type has the following parameters:
23722 @item @code{pam-krb5} (default: @code{pam-krb5})
23723 The pam-krb5 package to use.
23725 @item @code{minimum-uid} (default: @code{1000})
23726 The smallest user ID for which Kerberos authentications should be attempted.
23727 Local accounts with lower values will silently fail to authenticate.
23732 @node LDAP Services
23733 @subsection LDAP Services
23735 @cindex nslcd, LDAP service
23737 The @code{(gnu services authentication)} module provides the
23738 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
23739 server. In addition to configuring the service itself, you may want to add
23740 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
23741 Switch} for detailed information.
23743 Here is a simple operating system declaration with a default configuration of
23744 the @code{nslcd-service-type} and a Name Service Switch configuration that
23745 consults the @code{ldap} name service last:
23748 (use-service-modules authentication)
23749 (use-modules (gnu system nss))
23755 (service nslcd-service-type)
23756 (service dhcp-client-service-type)
23758 (name-service-switch
23759 (let ((services (list (name-service (name "db"))
23760 (name-service (name "files"))
23761 (name-service (name "ldap")))))
23762 (name-service-switch
23763 (inherit %mdns-host-lookup-nss)
23764 (password services)
23767 (netgroup services)
23768 (gshadow services)))))
23771 @c %start of generated documentation for nslcd-configuration
23773 Available @code{nslcd-configuration} fields are:
23775 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
23776 The @code{nss-pam-ldapd} package to use.
23780 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
23781 The number of threads to start that can handle requests and perform LDAP
23782 queries. Each thread opens a separate connection to the LDAP server.
23783 The default is to start 5 threads.
23785 Defaults to @samp{disabled}.
23789 @deftypevr {@code{nslcd-configuration} parameter} string uid
23790 This specifies the user id with which the daemon should be run.
23792 Defaults to @samp{"nslcd"}.
23796 @deftypevr {@code{nslcd-configuration} parameter} string gid
23797 This specifies the group id with which the daemon should be run.
23799 Defaults to @samp{"nslcd"}.
23803 @deftypevr {@code{nslcd-configuration} parameter} log-option log
23804 This option controls the way logging is done via a list containing
23805 SCHEME and LEVEL@. The SCHEME argument may either be the symbols
23806 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
23807 argument is optional and specifies the log level. The log level may be
23808 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
23809 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
23810 specified log level or higher are logged.
23812 Defaults to @samp{("/var/log/nslcd" info)}.
23816 @deftypevr {@code{nslcd-configuration} parameter} list uri
23817 The list of LDAP server URIs. Normally, only the first server will be
23818 used with the following servers as fall-back.
23820 Defaults to @samp{("ldap://localhost:389/")}.
23824 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
23825 The version of the LDAP protocol to use. The default is to use the
23826 maximum version supported by the LDAP library.
23828 Defaults to @samp{disabled}.
23832 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
23833 Specifies the distinguished name with which to bind to the directory
23834 server for lookups. The default is to bind anonymously.
23836 Defaults to @samp{disabled}.
23840 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
23841 Specifies the credentials with which to bind. This option is only
23842 applicable when used with binddn.
23844 Defaults to @samp{disabled}.
23848 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
23849 Specifies the distinguished name to use when the root user tries to
23850 modify a user's password using the PAM module.
23852 Defaults to @samp{disabled}.
23856 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
23857 Specifies the credentials with which to bind if the root user tries to
23858 change a user's password. This option is only applicable when used with
23861 Defaults to @samp{disabled}.
23865 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
23866 Specifies the SASL mechanism to be used when performing SASL
23869 Defaults to @samp{disabled}.
23873 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
23874 Specifies the SASL realm to be used when performing SASL authentication.
23876 Defaults to @samp{disabled}.
23880 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
23881 Specifies the authentication identity to be used when performing SASL
23884 Defaults to @samp{disabled}.
23888 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
23889 Specifies the authorization identity to be used when performing SASL
23892 Defaults to @samp{disabled}.
23896 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
23897 Determines whether the LDAP server host name should be canonicalised. If
23898 this is enabled the LDAP library will do a reverse host name lookup. By
23899 default, it is left up to the LDAP library whether this check is
23902 Defaults to @samp{disabled}.
23906 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
23907 Set the name for the GSS-API Kerberos credentials cache.
23909 Defaults to @samp{disabled}.
23913 @deftypevr {@code{nslcd-configuration} parameter} string base
23914 The directory search base.
23916 Defaults to @samp{"dc=example,dc=com"}.
23920 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
23921 Specifies the search scope (subtree, onelevel, base or children). The
23922 default scope is subtree; base scope is almost never useful for name
23923 service lookups; children scope is not supported on all servers.
23925 Defaults to @samp{(subtree)}.
23929 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
23930 Specifies the policy for dereferencing aliases. The default policy is
23931 to never dereference aliases.
23933 Defaults to @samp{disabled}.
23937 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
23938 Specifies whether automatic referral chasing should be enabled. The
23939 default behaviour is to chase referrals.
23941 Defaults to @samp{disabled}.
23945 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
23946 This option allows for custom attributes to be looked up instead of the
23947 default RFC 2307 attributes. It is a list of maps, each consisting of
23948 the name of a map, the RFC 2307 attribute to match and the query
23949 expression for the attribute as it is available in the directory.
23951 Defaults to @samp{()}.
23955 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
23956 A list of filters consisting of the name of a map to which the filter
23957 applies and an LDAP search filter expression.
23959 Defaults to @samp{()}.
23963 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
23964 Specifies the time limit in seconds to use when connecting to the
23965 directory server. The default value is 10 seconds.
23967 Defaults to @samp{disabled}.
23971 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
23972 Specifies the time limit (in seconds) to wait for a response from the
23973 LDAP server. A value of zero, which is the default, is to wait
23974 indefinitely for searches to be completed.
23976 Defaults to @samp{disabled}.
23980 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
23981 Specifies the period if inactivity (in seconds) after which the con‐
23982 nection to the LDAP server will be closed. The default is not to time
23985 Defaults to @samp{disabled}.
23989 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
23990 Specifies the number of seconds to sleep when connecting to all LDAP
23991 servers fails. By default one second is waited between the first
23992 failure and the first retry.
23994 Defaults to @samp{disabled}.
23998 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
23999 Specifies the time after which the LDAP server is considered to be
24000 permanently unavailable. Once this time is reached retries will be done
24001 only once per this time period. The default value is 10 seconds.
24003 Defaults to @samp{disabled}.
24007 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
24008 Specifies whether to use SSL/TLS or not (the default is not to). If
24009 'start-tls is specified then StartTLS is used rather than raw LDAP over
24012 Defaults to @samp{disabled}.
24016 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
24017 Specifies what checks to perform on a server-supplied certificate. The
24018 meaning of the values is described in the ldap.conf(5) manual page.
24020 Defaults to @samp{disabled}.
24024 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
24025 Specifies the directory containing X.509 certificates for peer authen‐
24026 tication. This parameter is ignored when using GnuTLS.
24028 Defaults to @samp{disabled}.
24032 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
24033 Specifies the path to the X.509 certificate for peer authentication.
24035 Defaults to @samp{disabled}.
24039 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
24040 Specifies the path to an entropy source. This parameter is ignored when
24043 Defaults to @samp{disabled}.
24047 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
24048 Specifies the ciphers to use for TLS as a string.
24050 Defaults to @samp{disabled}.
24054 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
24055 Specifies the path to the file containing the local certificate for
24056 client TLS authentication.
24058 Defaults to @samp{disabled}.
24062 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
24063 Specifies the path to the file containing the private key for client TLS
24066 Defaults to @samp{disabled}.
24070 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
24071 Set this to a number greater than 0 to request paged results from the
24072 LDAP server in accordance with RFC2696. The default (0) is to not
24073 request paged results.
24075 Defaults to @samp{disabled}.
24079 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
24080 This option prevents group membership lookups through LDAP for the
24081 specified users. Alternatively, the value 'all-local may be used. With
24082 that value nslcd builds a full list of non-LDAP users on startup.
24084 Defaults to @samp{disabled}.
24088 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
24089 This option ensures that LDAP users with a numeric user id lower than
24090 the specified value are ignored.
24092 Defaults to @samp{disabled}.
24096 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
24097 This option specifies an offset that is added to all LDAP numeric user
24098 ids. This can be used to avoid user id collisions with local users.
24100 Defaults to @samp{disabled}.
24104 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
24105 This option specifies an offset that is added to all LDAP numeric group
24106 ids. This can be used to avoid user id collisions with local groups.
24108 Defaults to @samp{disabled}.
24112 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
24113 If this option is set, the member attribute of a group may point to
24114 another group. Members of nested groups are also returned in the higher
24115 level group and parent groups are returned when finding groups for a
24116 specific user. The default is not to perform extra searches for nested
24119 Defaults to @samp{disabled}.
24123 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
24124 If this option is set, the group member list is not retrieved when
24125 looking up groups. Lookups for finding which groups a user belongs to
24126 will remain functional so the user will likely still get the correct
24127 groups assigned on login.
24129 Defaults to @samp{disabled}.
24133 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
24134 If this option is set, functions which cause all user/group entries to
24135 be loaded from the directory will not succeed in doing so. This can
24136 dramatically reduce LDAP server load in situations where there are a
24137 great number of users and/or groups. This option is not recommended for
24138 most configurations.
24140 Defaults to @samp{disabled}.
24144 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
24145 This option can be used to specify how user and group names are verified
24146 within the system. This pattern is used to check all user and group
24147 names that are requested and returned from LDAP.
24149 Defaults to @samp{disabled}.
24153 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
24154 This specifies whether or not to perform searches using case-insensitive
24155 matching. Enabling this could open up the system to authorization
24156 bypass vulnerabilities and introduce nscd cache poisoning
24157 vulnerabilities which allow denial of service.
24159 Defaults to @samp{disabled}.
24163 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
24164 This option specifies whether password policy controls are requested and
24165 handled from the LDAP server when performing user authentication.
24167 Defaults to @samp{disabled}.
24171 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
24172 By default nslcd performs an LDAP search with the user's credentials
24173 after BIND (authentication) to ensure that the BIND operation was
24174 successful. The default search is a simple check to see if the user's
24175 DN exists. A search filter can be specified that will be used instead.
24176 It should return at least one entry.
24178 Defaults to @samp{disabled}.
24182 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
24183 This option allows flexible fine tuning of the authorisation check that
24184 should be performed. The search filter specified is executed and if any
24185 entries match, access is granted, otherwise access is denied.
24187 Defaults to @samp{disabled}.
24191 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
24192 If this option is set password modification using pam_ldap will be
24193 denied and the specified message will be presented to the user instead.
24194 The message can be used to direct the user to an alternative means of
24195 changing their password.
24197 Defaults to @samp{disabled}.
24201 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
24202 List of pam service names for which LDAP authentication should suffice.
24204 Defaults to @samp{()}.
24208 @c %end of generated documentation for nslcd-configuration
24212 @subsection Web Services
24217 The @code{(gnu services web)} module provides the Apache HTTP Server,
24218 the nginx web server, and also a fastcgi wrapper daemon.
24220 @subsubheading Apache HTTP Server
24222 @deffn {Scheme Variable} httpd-service-type
24223 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
24224 (@dfn{httpd}). The value for this service type is a
24225 @code{httpd-configuration} record.
24227 A simple example configuration is given below.
24230 (service httpd-service-type
24231 (httpd-configuration
24234 (server-name "www.example.com")
24235 (document-root "/srv/http/www.example.com")))))
24238 Other services can also extend the @code{httpd-service-type} to add to
24242 (simple-service 'www.example.com-server httpd-service-type
24246 (list (string-join '("ServerName www.example.com"
24247 "DocumentRoot /srv/http/www.example.com")
24252 The details for the @code{httpd-configuration}, @code{httpd-module},
24253 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
24256 @deffn {Data Type} httpd-configuration
24257 This data type represents the configuration for the httpd service.
24260 @item @code{package} (default: @code{httpd})
24261 The httpd package to use.
24263 @item @code{pid-file} (default: @code{"/var/run/httpd"})
24264 The pid file used by the shepherd-service.
24266 @item @code{config} (default: @code{(httpd-config-file)})
24267 The configuration file to use with the httpd service. The default value
24268 is a @code{httpd-config-file} record, but this can also be a different
24269 G-expression that generates a file, for example a @code{plain-file}. A
24270 file outside of the store can also be specified through a string.
24275 @deffn {Data Type} httpd-module
24276 This data type represents a module for the httpd service.
24280 The name of the module.
24283 The file for the module. This can be relative to the httpd package being
24284 used, the absolute location of a file, or a G-expression for a file
24285 within the store, for example @code{(file-append mod-wsgi
24286 "/modules/mod_wsgi.so")}.
24291 @defvr {Scheme Variable} %default-httpd-modules
24292 A default list of @code{httpd-module} objects.
24295 @deffn {Data Type} httpd-config-file
24296 This data type represents a configuration file for the httpd service.
24299 @item @code{modules} (default: @code{%default-httpd-modules})
24300 The modules to load. Additional modules can be added here, or loaded by
24301 additional configuration.
24303 For example, in order to handle requests for PHP files, you can use Apache’s
24304 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
24307 (service httpd-service-type
24308 (httpd-configuration
24313 (name "proxy_module")
24314 (file "modules/mod_proxy.so"))
24316 (name "proxy_fcgi_module")
24317 (file "modules/mod_proxy_fcgi.so"))
24318 %default-httpd-modules))
24319 (extra-config (list "\
24320 <FilesMatch \\.php$>
24321 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
24322 </FilesMatch>"))))))
24323 (service php-fpm-service-type
24324 (php-fpm-configuration
24325 (socket "/var/run/php-fpm.sock")
24326 (socket-group "httpd")))
24329 @item @code{server-root} (default: @code{httpd})
24330 The @code{ServerRoot} in the configuration file, defaults to the httpd
24331 package. Directives including @code{Include} and @code{LoadModule} are
24332 taken as relative to the server root.
24334 @item @code{server-name} (default: @code{#f})
24335 The @code{ServerName} in the configuration file, used to specify the
24336 request scheme, hostname and port that the server uses to identify
24339 This doesn't need to be set in the server config, and can be specified
24340 in virtual hosts. The default is @code{#f} to not specify a
24343 @item @code{document-root} (default: @code{"/srv/http"})
24344 The @code{DocumentRoot} from which files will be served.
24346 @item @code{listen} (default: @code{'("80")})
24347 The list of values for the @code{Listen} directives in the config
24348 file. The value should be a list of strings, when each string can
24349 specify the port number to listen on, and optionally the IP address and
24352 @item @code{pid-file} (default: @code{"/var/run/httpd"})
24353 The @code{PidFile} to use. This should match the @code{pid-file} set in
24354 the @code{httpd-configuration} so that the Shepherd service is
24355 configured correctly.
24357 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
24358 The @code{ErrorLog} to which the server will log errors.
24360 @item @code{user} (default: @code{"httpd"})
24361 The @code{User} which the server will answer requests as.
24363 @item @code{group} (default: @code{"httpd"})
24364 The @code{Group} which the server will answer requests as.
24366 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
24367 A flat list of strings and G-expressions which will be added to the end
24368 of the configuration file.
24370 Any values which the service is extended with will be appended to this
24376 @deffn {Data Type} httpd-virtualhost
24377 This data type represents a virtualhost configuration block for the httpd service.
24379 These should be added to the extra-config for the httpd-service.
24382 (simple-service 'www.example.com-server httpd-service-type
24386 (list (string-join '("ServerName www.example.com"
24387 "DocumentRoot /srv/http/www.example.com")
24392 @item @code{addresses-and-ports}
24393 The addresses and ports for the @code{VirtualHost} directive.
24395 @item @code{contents}
24396 The contents of the @code{VirtualHost} directive, this should be a list
24397 of strings and G-expressions.
24402 @subsubheading NGINX
24404 @deffn {Scheme Variable} nginx-service-type
24405 Service type for the @uref{https://nginx.org/,NGinx} web server. The
24406 value for this service type is a @code{<nginx-configuration>} record.
24408 A simple example configuration is given below.
24411 (service nginx-service-type
24412 (nginx-configuration
24414 (list (nginx-server-configuration
24415 (server-name '("www.example.com"))
24416 (root "/srv/http/www.example.com"))))))
24419 In addition to adding server blocks to the service configuration
24420 directly, this service can be extended by other services to add server
24421 blocks, as in this example:
24424 (simple-service 'my-extra-server nginx-service-type
24425 (list (nginx-server-configuration
24426 (root "/srv/http/extra-website")
24427 (try-files (list "$uri" "$uri/index.html")))))
24431 At startup, @command{nginx} has not yet read its configuration file, so
24432 it uses a default file to log error messages. If it fails to load its
24433 configuration file, that is where error messages are logged. After the
24434 configuration file is loaded, the default error log file changes as per
24435 configuration. In our case, startup error messages can be found in
24436 @file{/var/run/nginx/logs/error.log}, and after configuration in
24437 @file{/var/log/nginx/error.log}. The second location can be changed
24438 with the @var{log-directory} configuration option.
24440 @deffn {Data Type} nginx-configuration
24441 This data type represents the configuration for NGinx. Some
24442 configuration can be done through this and the other provided record
24443 types, or alternatively, a config file can be provided.
24446 @item @code{nginx} (default: @code{nginx})
24447 The nginx package to use.
24449 @item @code{log-directory} (default: @code{"/var/log/nginx"})
24450 The directory to which NGinx will write log files.
24452 @item @code{run-directory} (default: @code{"/var/run/nginx"})
24453 The directory in which NGinx will create a pid file, and write temporary
24456 @item @code{server-blocks} (default: @code{'()})
24457 A list of @dfn{server blocks} to create in the generated configuration
24458 file, the elements should be of type
24459 @code{<nginx-server-configuration>}.
24461 The following example would setup NGinx to serve @code{www.example.com}
24462 from the @code{/srv/http/www.example.com} directory, without using
24465 (service nginx-service-type
24466 (nginx-configuration
24468 (list (nginx-server-configuration
24469 (server-name '("www.example.com"))
24470 (root "/srv/http/www.example.com"))))))
24473 @item @code{upstream-blocks} (default: @code{'()})
24474 A list of @dfn{upstream blocks} to create in the generated configuration
24475 file, the elements should be of type
24476 @code{<nginx-upstream-configuration>}.
24478 Configuring upstreams through the @code{upstream-blocks} can be useful
24479 when combined with @code{locations} in the
24480 @code{<nginx-server-configuration>} records. The following example
24481 creates a server configuration with one location configuration, that
24482 will proxy requests to a upstream configuration, which will handle
24483 requests with two servers.
24488 (nginx-configuration
24490 (list (nginx-server-configuration
24491 (server-name '("www.example.com"))
24492 (root "/srv/http/www.example.com")
24495 (nginx-location-configuration
24497 (body '("proxy_pass http://server-proxy;"))))))))
24499 (list (nginx-upstream-configuration
24500 (name "server-proxy")
24501 (servers (list "server1.example.com"
24502 "server2.example.com")))))))
24505 @item @code{file} (default: @code{#f})
24506 If a configuration @var{file} is provided, this will be used, rather than
24507 generating a configuration file from the provided @code{log-directory},
24508 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
24509 proper operation, these arguments should match what is in @var{file} to ensure
24510 that the directories are created when the service is activated.
24512 This can be useful if you have an existing configuration file, or it's
24513 not possible to do what is required through the other parts of the
24514 nginx-configuration record.
24516 @item @code{server-names-hash-bucket-size} (default: @code{#f})
24517 Bucket size for the server names hash tables, defaults to @code{#f} to
24518 use the size of the processors cache line.
24520 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
24521 Maximum bucket size for the server names hash tables.
24523 @item @code{modules} (default: @code{'()})
24524 List of nginx dynamic modules to load. This should be a list of file
24525 names of loadable modules, as in this example:
24530 (file-append nginx-accept-language-module "\
24531 /etc/nginx/modules/ngx_http_accept_language_module.so")
24532 (file-append nginx-lua-module "\
24533 /etc/nginx/modules/ngx_http_lua_module.so")))
24536 @item @code{lua-package-path} (default: @code{'()})
24537 List of nginx lua packages to load. This should be a list of package
24538 names of loadable lua modules, as in this example:
24541 (lua-package-path (list lua-resty-core
24548 @item @code{lua-package-cpath} (default: @code{'()})
24549 List of nginx lua C packages to load. This should be a list of package
24550 names of loadable lua C modules, as in this example:
24553 (lua-package-cpath (list lua-resty-signal))
24556 @item @code{global-directives} (default: @code{'((events . ()))})
24557 Association list of global directives for the top level of the nginx
24558 configuration. Values may themselves be association lists.
24562 `((worker_processes . 16)
24564 (events . ((worker_connections . 1024)))))
24567 @item @code{extra-content} (default: @code{""})
24568 Extra content for the @code{http} block. Should be string or a string
24569 valued G-expression.
24574 @deftp {Data Type} nginx-server-configuration
24575 Data type representing the configuration of an nginx server block.
24576 This type has the following parameters:
24579 @item @code{listen} (default: @code{'("80" "443 ssl")})
24580 Each @code{listen} directive sets the address and port for IP, or the
24581 path for a UNIX-domain socket on which the server will accept requests.
24582 Both address and port, or only address or only port can be specified.
24583 An address may also be a hostname, for example:
24586 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
24589 @item @code{server-name} (default: @code{(list 'default)})
24590 A list of server names this server represents. @code{'default} represents the
24591 default server for connections matching no other server.
24593 @item @code{root} (default: @code{"/srv/http"})
24594 Root of the website nginx will serve.
24596 @item @code{locations} (default: @code{'()})
24597 A list of @dfn{nginx-location-configuration} or
24598 @dfn{nginx-named-location-configuration} records to use within this
24601 @item @code{index} (default: @code{(list "index.html")})
24602 Index files to look for when clients ask for a directory. If it cannot be found,
24603 Nginx will send the list of files in the directory.
24605 @item @code{try-files} (default: @code{'()})
24606 A list of files whose existence is checked in the specified order.
24607 @code{nginx} will use the first file it finds to process the request.
24609 @item @code{ssl-certificate} (default: @code{#f})
24610 Where to find the certificate for secure connections. Set it to @code{#f} if
24611 you don't have a certificate or you don't want to use HTTPS.
24613 @item @code{ssl-certificate-key} (default: @code{#f})
24614 Where to find the private key for secure connections. Set it to @code{#f} if
24615 you don't have a key or you don't want to use HTTPS.
24617 @item @code{server-tokens?} (default: @code{#f})
24618 Whether the server should add its configuration to response.
24620 @item @code{raw-content} (default: @code{'()})
24621 A list of raw lines added to the server block.
24626 @deftp {Data Type} nginx-upstream-configuration
24627 Data type representing the configuration of an nginx @code{upstream}
24628 block. This type has the following parameters:
24632 Name for this group of servers.
24634 @item @code{servers}
24635 Specify the addresses of the servers in the group. The address can be
24636 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
24637 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
24638 prefix @samp{unix:}. For addresses using an IP address or domain name,
24639 the default port is 80, and a different port can be specified
24645 @deftp {Data Type} nginx-location-configuration
24646 Data type representing the configuration of an nginx @code{location}
24647 block. This type has the following parameters:
24651 URI which this location block matches.
24653 @anchor{nginx-location-configuration body}
24655 Body of the location block, specified as a list of strings. This can contain
24657 configuration directives. For example, to pass requests to a upstream
24658 server group defined using an @code{nginx-upstream-configuration} block,
24659 the following directive would be specified in the body @samp{(list "proxy_pass
24660 http://upstream-name;")}.
24665 @deftp {Data Type} nginx-named-location-configuration
24666 Data type representing the configuration of an nginx named location
24667 block. Named location blocks are used for request redirection, and not
24668 used for regular request processing. This type has the following
24673 Name to identify this location block.
24676 @xref{nginx-location-configuration body}, as the body for named location
24677 blocks can be used in a similar way to the
24678 @code{nginx-location-configuration body}. One restriction is that the
24679 body of a named location block cannot contain location blocks.
24684 @subsubheading Varnish Cache
24686 Varnish is a fast cache server that sits in between web applications
24687 and end users. It proxies requests from clients and caches the
24688 accessed URLs such that multiple requests for the same resource only
24689 creates one request to the back-end.
24691 @defvr {Scheme Variable} varnish-service-type
24692 Service type for the Varnish daemon.
24695 @deftp {Data Type} varnish-configuration
24696 Data type representing the @code{varnish} service configuration.
24697 This type has the following parameters:
24700 @item @code{package} (default: @code{varnish})
24701 The Varnish package to use.
24703 @item @code{name} (default: @code{"default"})
24704 A name for this Varnish instance. Varnish will create a directory in
24705 @file{/var/varnish/} with this name and keep temporary files there. If
24706 the name starts with a forward slash, it is interpreted as an absolute
24709 Pass the @code{-n} argument to other Varnish programs to connect to the
24710 named instance, e.g.@: @command{varnishncsa -n default}.
24712 @item @code{backend} (default: @code{"localhost:8080"})
24713 The backend to use. This option has no effect if @code{vcl} is set.
24715 @item @code{vcl} (default: #f)
24716 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
24717 is @code{#f}, Varnish will proxy @code{backend} using the default
24718 configuration. Otherwise this must be a file-like object with valid
24721 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
24722 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
24723 can do something along these lines:
24726 (define %gnu-mirror
24727 (plain-file "gnu.vcl"
24729 backend gnu @{ .host = \"www.gnu.org\"; @}"))
24733 (services (cons (service varnish-service-type
24734 (varnish-configuration
24736 (vcl %gnu-mirror)))
24740 The configuration of an already running Varnish instance can be inspected
24741 and changed using the @command{varnishadm} program.
24743 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
24744 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
24745 comprehensive documentation on Varnish and its configuration language.
24747 @item @code{listen} (default: @code{'("localhost:80")})
24748 List of addresses Varnish will listen on.
24750 @item @code{storage} (default: @code{'("malloc,128m")})
24751 List of storage backends that will be available in VCL.
24753 @item @code{parameters} (default: @code{'()})
24754 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
24756 @item @code{extra-options} (default: @code{'()})
24757 Additional arguments to pass to the @command{varnishd} process.
24762 @subsubheading Patchwork
24764 Patchwork is a patch tracking system. It can collect patches sent to a
24765 mailing list, and display them in a web interface.
24767 @defvr {Scheme Variable} patchwork-service-type
24768 Service type for Patchwork.
24771 The following example is an example of a minimal service for Patchwork, for
24772 the @code{patchwork.example.com} domain.
24775 (service patchwork-service-type
24776 (patchwork-configuration
24777 (domain "patchwork.example.com")
24779 (patchwork-settings-module
24780 (allowed-hosts (list domain))
24781 (default-from-email "patchwork@@patchwork.example.com")))
24782 (getmail-retriever-config
24783 (getmail-retriever-configuration
24784 (type "SimpleIMAPSSLRetriever")
24785 (server "imap.example.com")
24787 (username "patchwork")
24789 (list (file-append coreutils "/bin/cat")
24790 "/etc/getmail-patchwork-imap-password"))
24792 '((mailboxes . ("Patches"))))))))
24796 There are three records for configuring the Patchwork service. The
24797 @code{<patchwork-configuration>} relates to the configuration for Patchwork
24798 within the HTTPD service.
24800 The @code{settings-module} field within the @code{<patchwork-configuration>}
24801 record can be populated with the @code{<patchwork-settings-module>} record,
24802 which describes a settings module that is generated within the Guix store.
24804 For the @code{database-configuration} field within the
24805 @code{<patchwork-settings-module>}, the
24806 @code{<patchwork-database-configuration>} must be used.
24808 @deftp {Data Type} patchwork-configuration
24809 Data type representing the Patchwork service configuration. This type has the
24810 following parameters:
24813 @item @code{patchwork} (default: @code{patchwork})
24814 The Patchwork package to use.
24816 @item @code{domain}
24817 The domain to use for Patchwork, this is used in the HTTPD service virtual
24820 @item @code{settings-module}
24821 The settings module to use for Patchwork. As a Django application, Patchwork
24822 is configured with a Python module containing the settings. This can either be
24823 an instance of the @code{<patchwork-settings-module>} record, any other record
24824 that represents the settings in the store, or a directory outside of the
24827 @item @code{static-path} (default: @code{"/static/"})
24828 The path under which the HTTPD service should serve the static files.
24830 @item @code{getmail-retriever-config}
24831 The getmail-retriever-configuration record value to use with
24832 Patchwork. Getmail will be configured with this value, the messages will be
24833 delivered to Patchwork.
24838 @deftp {Data Type} patchwork-settings-module
24839 Data type representing a settings module for Patchwork. Some of these
24840 settings relate directly to Patchwork, but others relate to Django, the web
24841 framework used by Patchwork, or the Django Rest Framework library. This type
24842 has the following parameters:
24845 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
24846 The database connection settings used for Patchwork. See the
24847 @code{<patchwork-database-configuration>} record type for more information.
24849 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
24850 Patchwork, as a Django web application uses a secret key for cryptographically
24851 signing values. This file should contain a unique unpredictable value.
24853 If this file does not exist, it will be created and populated with a random
24854 value by the patchwork-setup shepherd service.
24856 This setting relates to Django.
24858 @item @code{allowed-hosts}
24859 A list of valid hosts for this Patchwork service. This should at least include
24860 the domain specified in the @code{<patchwork-configuration>} record.
24862 This is a Django setting.
24864 @item @code{default-from-email}
24865 The email address from which Patchwork should send email by default.
24867 This is a Patchwork setting.
24869 @item @code{static-url} (default: @code{#f})
24870 The URL to use when serving static assets. It can be part of a URL, or a full
24871 URL, but must end in a @code{/}.
24873 If the default value is used, the @code{static-path} value from the
24874 @code{<patchwork-configuration>} record will be used.
24876 This is a Django setting.
24878 @item @code{admins} (default: @code{'()})
24879 Email addresses to send the details of errors that occur. Each value should
24880 be a list containing two elements, the name and then the email address.
24882 This is a Django setting.
24884 @item @code{debug?} (default: @code{#f})
24885 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
24886 messages will be shown.
24888 This is a Django setting.
24890 @item @code{enable-rest-api?} (default: @code{#t})
24891 Whether to enable the Patchwork REST API.
24893 This is a Patchwork setting.
24895 @item @code{enable-xmlrpc?} (default: @code{#t})
24896 Whether to enable the XML RPC API.
24898 This is a Patchwork setting.
24900 @item @code{force-https-links?} (default: @code{#t})
24901 Whether to use HTTPS links on Patchwork pages.
24903 This is a Patchwork setting.
24905 @item @code{extra-settings} (default: @code{""})
24906 Extra code to place at the end of the Patchwork settings module.
24911 @deftp {Data Type} patchwork-database-configuration
24912 Data type representing the database configuration for Patchwork.
24915 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
24916 The database engine to use.
24918 @item @code{name} (default: @code{"patchwork"})
24919 The name of the database to use.
24921 @item @code{user} (default: @code{"httpd"})
24922 The user to connect to the database as.
24924 @item @code{password} (default: @code{""})
24925 The password to use when connecting to the database.
24927 @item @code{host} (default: @code{""})
24928 The host to make the database connection to.
24930 @item @code{port} (default: @code{""})
24931 The port on which to connect to the database.
24936 @subsubheading Mumi
24938 @cindex Mumi, Debbugs Web interface
24939 @cindex Debbugs, Mumi Web interface
24940 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
24941 Web interface to the Debbugs bug tracker, by default for
24942 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
24943 but it also fetches and indexes mail retrieved from Debbugs.
24945 @defvr {Scheme Variable} mumi-service-type
24946 This is the service type for Mumi.
24949 @deftp {Data Type} mumi-configuration
24950 Data type representing the Mumi service configuration. This type has the
24954 @item @code{mumi} (default: @code{mumi})
24955 The Mumi package to use.
24957 @item @code{mailer?} (default: @code{#true})
24958 Whether to enable or disable the mailer component.
24960 @item @code{mumi-configuration-sender}
24961 The email address used as the sender for comments.
24963 @item @code{mumi-configuration-smtp}
24964 A URI to configure the SMTP settings for Mailutils. This could be
24965 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
24966 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
24967 mailutils, GNU@tie{}Mailutils}.
24973 @subsubheading FastCGI
24976 FastCGI is an interface between the front-end and the back-end of a web
24977 service. It is a somewhat legacy facility; new web services should
24978 generally just talk HTTP between the front-end and the back-end.
24979 However there are a number of back-end services such as PHP or the
24980 optimized HTTP Git repository access that use FastCGI, so we have
24981 support for it in Guix.
24983 To use FastCGI, you configure the front-end web server (e.g., nginx) to
24984 dispatch some subset of its requests to the fastcgi backend, which
24985 listens on a local TCP or UNIX socket. There is an intermediary
24986 @code{fcgiwrap} program that sits between the actual backend process and
24987 the web server. The front-end indicates which backend program to run,
24988 passing that information to the @code{fcgiwrap} process.
24990 @defvr {Scheme Variable} fcgiwrap-service-type
24991 A service type for the @code{fcgiwrap} FastCGI proxy.
24994 @deftp {Data Type} fcgiwrap-configuration
24995 Data type representing the configuration of the @code{fcgiwrap} service.
24996 This type has the following parameters:
24998 @item @code{package} (default: @code{fcgiwrap})
24999 The fcgiwrap package to use.
25001 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
25002 The socket on which the @code{fcgiwrap} process should listen, as a
25003 string. Valid @var{socket} values include
25004 @code{unix:@var{/path/to/unix/socket}},
25005 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
25006 @code{tcp6:[@var{ipv6_addr}]:port}.
25008 @item @code{user} (default: @code{fcgiwrap})
25009 @itemx @code{group} (default: @code{fcgiwrap})
25010 The user and group names, as strings, under which to run the
25011 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
25012 the user asks for the specific user or group names @code{fcgiwrap} that
25013 the corresponding user and/or group is present on the system.
25015 It is possible to configure a FastCGI-backed web service to pass HTTP
25016 authentication information from the front-end to the back-end, and to
25017 allow @code{fcgiwrap} to run the back-end process as a corresponding
25018 local user. To enable this capability on the back-end, run
25019 @code{fcgiwrap} as the @code{root} user and group. Note that this
25020 capability also has to be configured on the front-end as well.
25025 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
25026 with some additional features useful for sites of any size.
25028 These features include:
25030 @item Adaptive process spawning
25031 @item Basic statistics (similar to Apache's mod_status)
25032 @item Advanced process management with graceful stop/start
25033 @item Ability to start workers with different uid/gid/chroot/environment
25034 and different php.ini (replaces safe_mode)
25035 @item Stdout & stderr logging
25036 @item Emergency restart in case of accidental opcode cache destruction
25037 @item Accelerated upload support
25038 @item Support for a "slowlog"
25039 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
25040 a special function to finish request & flush all data while continuing to do
25041 something time-consuming (video converting, stats processing, etc.)
25043 ...@: and much more.
25045 @defvr {Scheme Variable} php-fpm-service-type
25046 A Service type for @code{php-fpm}.
25049 @deftp {Data Type} php-fpm-configuration
25050 Data Type for php-fpm service configuration.
25052 @item @code{php} (default: @code{php})
25053 The php package to use.
25054 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
25055 The address on which to accept FastCGI requests. Valid syntaxes are:
25057 @item @code{"ip.add.re.ss:port"}
25058 Listen on a TCP socket to a specific address on a specific port.
25059 @item @code{"port"}
25060 Listen on a TCP socket to all addresses on a specific port.
25061 @item @code{"/path/to/unix/socket"}
25062 Listen on a unix socket.
25065 @item @code{user} (default: @code{php-fpm})
25066 User who will own the php worker processes.
25067 @item @code{group} (default: @code{php-fpm})
25068 Group of the worker processes.
25069 @item @code{socket-user} (default: @code{php-fpm})
25070 User who can speak to the php-fpm socket.
25071 @item @code{socket-group} (default: @code{nginx})
25072 Group that can speak to the php-fpm socket.
25073 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
25074 The process id of the php-fpm process is written to this file
25075 once the service has started.
25076 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
25077 Log for the php-fpm master process.
25078 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
25079 Detailed settings for the php-fpm process manager.
25082 @item @code{<php-fpm-dynamic-process-manager-configuration>}
25083 @item @code{<php-fpm-static-process-manager-configuration>}
25084 @item @code{<php-fpm-on-demand-process-manager-configuration>}
25086 @item @code{display-errors} (default @code{#f})
25087 Determines whether php errors and warning should be sent to clients
25088 and displayed in their browsers.
25089 This is useful for local php development, but a security risk for public sites,
25090 as error messages can reveal passwords and personal data.
25091 @item @code{timezone} (default @code{#f})
25092 Specifies @code{php_admin_value[date.timezone]} parameter.
25093 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
25094 This file will log the @code{stderr} outputs of php worker processes.
25095 Can be set to @code{#f} to disable logging.
25096 @item @code{file} (default @code{#f})
25097 An optional override of the whole configuration.
25098 You can use the @code{mixed-text-file} function or an absolute filepath for it.
25099 @item @code{php-ini-file} (default @code{#f})
25100 An optional override of the default php settings.
25101 It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
25102 You can use the @code{mixed-text-file} function or an absolute filepath for it.
25104 For local development it is useful to set a higher timeout and memory
25105 limit for spawned php processes. This be accomplished with the
25106 following operating system configuration snippet:
25108 (define %local-php-ini
25109 (plain-file "php.ini"
25111 max_execution_time = 1800"))
25115 (services (cons (service php-fpm-service-type
25116 (php-fpm-configuration
25117 (php-ini-file %local-php-ini)))
25121 Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
25122 directives} for comprehensive documentation on the acceptable
25123 @file{php.ini} directives.
25127 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
25128 Data Type for the @code{dynamic} php-fpm process manager. With the
25129 @code{dynamic} process manager, spare worker processes are kept around
25130 based on it's configured limits.
25132 @item @code{max-children} (default: @code{5})
25133 Maximum of worker processes.
25134 @item @code{start-servers} (default: @code{2})
25135 How many worker processes should be started on start-up.
25136 @item @code{min-spare-servers} (default: @code{1})
25137 How many spare worker processes should be kept around at minimum.
25138 @item @code{max-spare-servers} (default: @code{3})
25139 How many spare worker processes should be kept around at maximum.
25143 @deftp {Data type} php-fpm-static-process-manager-configuration
25144 Data Type for the @code{static} php-fpm process manager. With the
25145 @code{static} process manager, an unchanging number of worker processes
25148 @item @code{max-children} (default: @code{5})
25149 Maximum of worker processes.
25153 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
25154 Data Type for the @code{on-demand} php-fpm process manager. With the
25155 @code{on-demand} process manager, worker processes are only created as
25158 @item @code{max-children} (default: @code{5})
25159 Maximum of worker processes.
25160 @item @code{process-idle-timeout} (default: @code{10})
25161 The time in seconds after which a process with no requests is killed.
25166 @deffn {Scheme Procedure} nginx-php-location @
25167 [#:nginx-package nginx] @
25168 [socket (string-append "/var/run/php" @
25169 (version-major (package-version php)) @
25171 A helper function to quickly add php to an @code{nginx-server-configuration}.
25174 A simple services setup for nginx with php can look like this:
25176 (services (cons* (service dhcp-client-service-type)
25177 (service php-fpm-service-type)
25178 (service nginx-service-type
25179 (nginx-server-configuration
25180 (server-name '("example.com"))
25181 (root "/srv/http/")
25183 (list (nginx-php-location)))
25185 (ssl-certificate #f)
25186 (ssl-certificate-key #f)))
25190 @cindex cat-avatar-generator
25191 The cat avatar generator is a simple service to demonstrate the use of php-fpm
25192 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
25193 the hash of a user's email address.
25195 @deffn {Scheme Procedure} cat-avatar-generator-service @
25196 [#:cache-dir "/var/cache/cat-avatar-generator"] @
25197 [#:package cat-avatar-generator] @
25198 [#:configuration (nginx-server-configuration)]
25199 Returns an nginx-server-configuration that inherits @code{configuration}. It
25200 extends the nginx configuration to add a server block that serves @code{package},
25201 a version of cat-avatar-generator. During execution, cat-avatar-generator will
25202 be able to use @code{cache-dir} as its cache directory.
25205 A simple setup for cat-avatar-generator can look like this:
25207 (services (cons* (cat-avatar-generator-service
25209 (nginx-server-configuration
25210 (server-name '("example.com"))))
25215 @subsubheading Hpcguix-web
25217 @cindex hpcguix-web
25218 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
25219 program is a customizable web interface to browse Guix packages,
25220 initially designed for users of high-performance computing (HPC)
25223 @defvr {Scheme Variable} hpcguix-web-service-type
25224 The service type for @code{hpcguix-web}.
25227 @deftp {Data Type} hpcguix-web-configuration
25228 Data type for the hpcguix-web service configuration.
25232 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
25233 configuration. The main items available in this spec are:
25236 @item @code{title-prefix} (default: @code{"hpcguix | "})
25237 The page title prefix.
25239 @item @code{guix-command} (default: @code{"guix"})
25240 The @command{guix} command.
25242 @item @code{package-filter-proc} (default: @code{(const #t)})
25243 A procedure specifying how to filter packages that are displayed.
25245 @item @code{package-page-extension-proc} (default: @code{(const '())})
25246 Extension package for @code{hpcguix-web}.
25248 @item @code{menu} (default: @code{'()})
25249 Additional entry in page @code{menu}.
25251 @item @code{channels} (default: @code{%default-channels})
25252 List of channels from which the package list is built (@pxref{Channels}).
25254 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
25255 The expiration time, in seconds, after which the package list is rebuilt from
25256 the latest instances of the given channels.
25259 See the hpcguix-web repository for a
25260 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
25263 @item @code{package} (default: @code{hpcguix-web})
25264 The hpcguix-web package to use.
25268 A typical hpcguix-web service declaration looks like this:
25271 (service hpcguix-web-service-type
25272 (hpcguix-web-configuration
25274 #~(define site-config
25275 (hpcweb-configuration
25276 (title-prefix "Guix-HPC - ")
25277 (menu '(("/about" "ABOUT"))))))))
25281 The hpcguix-web service periodically updates the package list it publishes by
25282 pulling channels from Git. To that end, it needs to access X.509 certificates
25283 so that it can authenticate Git servers when communicating over HTTPS, and it
25284 assumes that @file{/etc/ssl/certs} contains those certificates.
25286 Thus, make sure to add @code{nss-certs} or another certificate package to the
25287 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
25288 more information on X.509 certificates.
25291 @subsubheading gmnisrv
25294 The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
25295 simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
25297 @deffn {Scheme Variable} gmnisrv-service-type
25298 This is the type of the gmnisrv service, whose value should be a
25299 @code{gmnisrv-configuration} object, as in this example:
25302 (service gmnisrv-service-type
25303 (gmnisrv-configuration
25304 (config-file (local-file "./my-gmnisrv.ini"))))
25308 @deftp {Data Type} gmnisrv-configuration
25309 Data type representing the configuration of gmnisrv.
25312 @item @code{package} (default: @var{gmnisrv})
25313 Package object of the gmnisrv server.
25315 @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
25316 File-like object of the gmnisrv configuration file to use. The default
25317 configuration listens on port 1965 and serves files from
25318 @file{/srv/gemini}. Certificates are stored in
25319 @file{/var/lib/gemini/certs}. For more information, run @command{man
25320 gmnisrv} and @command{man gmnisrv.ini}.
25325 @node Certificate Services
25326 @subsection Certificate Services
25329 @cindex HTTP, HTTPS
25330 @cindex Let's Encrypt
25331 @cindex TLS certificates
25332 The @code{(gnu services certbot)} module provides a service to
25333 automatically obtain a valid TLS certificate from the Let's Encrypt
25334 certificate authority. These certificates can then be used to serve
25335 content securely over HTTPS or other TLS-based protocols, with the
25336 knowledge that the client will be able to verify the server's
25339 @url{https://letsencrypt.org/, Let's Encrypt} provides the
25340 @code{certbot} tool to automate the certification process. This tool
25341 first securely generates a key on the server. It then makes a request
25342 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
25343 checks that the request originates from the host in question by using a
25344 challenge-response protocol, requiring the server to provide its
25345 response over HTTP@. If that protocol completes successfully, the CA
25346 signs the key, resulting in a certificate. That certificate is valid
25347 for a limited period of time, and therefore to continue to provide TLS
25348 services, the server needs to periodically ask the CA to renew its
25351 The certbot service automates this process: the initial key
25352 generation, the initial certification request to the Let's Encrypt
25353 service, the web server challenge/response integration, writing the
25354 certificate to disk, the automated periodic renewals, and the deployment
25355 tasks associated with the renewal (e.g.@: reloading services, copying keys
25356 with different permissions).
25358 Certbot is run twice a day, at a random minute within the hour. It
25359 won't do anything until your certificates are due for renewal or
25360 revoked, but running it regularly would give your service a chance of
25361 staying online in case a Let's Encrypt-initiated revocation happened for
25364 By using this service, you agree to the ACME Subscriber Agreement, which
25365 can be found there:
25366 @url{https://acme-v01.api.letsencrypt.org/directory}.
25368 @defvr {Scheme Variable} certbot-service-type
25369 A service type for the @code{certbot} Let's Encrypt client. Its value
25370 must be a @code{certbot-configuration} record as in this example:
25373 (define %nginx-deploy-hook
25375 "nginx-deploy-hook"
25376 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
25377 (kill pid SIGHUP))))
25379 (service certbot-service-type
25380 (certbot-configuration
25381 (email "foo@@example.net")
25384 (certificate-configuration
25385 (domains '("example.net" "www.example.net"))
25386 (deploy-hook %nginx-deploy-hook))
25387 (certificate-configuration
25388 (domains '("bar.example.net")))))))
25391 See below for details about @code{certbot-configuration}.
25394 @deftp {Data Type} certbot-configuration
25395 Data type representing the configuration of the @code{certbot} service.
25396 This type has the following parameters:
25399 @item @code{package} (default: @code{certbot})
25400 The certbot package to use.
25402 @item @code{webroot} (default: @code{/var/www})
25403 The directory from which to serve the Let's Encrypt challenge/response
25406 @item @code{certificates} (default: @code{()})
25407 A list of @code{certificates-configuration}s for which to generate
25408 certificates and request signatures. Each certificate has a @code{name}
25409 and several @code{domains}.
25411 @item @code{email} (default: @code{#f})
25412 Optional email address used for registration and recovery contact.
25413 Setting this is encouraged as it allows you to receive important
25414 notifications about the account and issued certificates.
25416 @item @code{server} (default: @code{#f})
25417 Optional URL of ACME server. Setting this overrides certbot's default,
25418 which is the Let's Encrypt server.
25420 @item @code{rsa-key-size} (default: @code{2048})
25421 Size of the RSA key.
25423 @item @code{default-location} (default: @i{see below})
25424 The default @code{nginx-location-configuration}. Because @code{certbot}
25425 needs to be able to serve challenges and responses, it needs to be able
25426 to run a web server. It does so by extending the @code{nginx} web
25427 service with an @code{nginx-server-configuration} listening on the
25428 @var{domains} on port 80, and which has a
25429 @code{nginx-location-configuration} for the @code{/.well-known/} URI
25430 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
25431 these nginx configuration data types.
25433 Requests to other URL paths will be matched by the
25434 @code{default-location}, which if present is added to all
25435 @code{nginx-server-configuration}s.
25437 By default, the @code{default-location} will issue a redirect from
25438 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
25439 you to define what to serve on your site via @code{https}.
25441 Pass @code{#f} to not issue a default location.
25445 @deftp {Data Type} certificate-configuration
25446 Data type representing the configuration of a certificate.
25447 This type has the following parameters:
25450 @item @code{name} (default: @i{see below})
25451 This name is used by Certbot for housekeeping and in file paths; it
25452 doesn't affect the content of the certificate itself. To see
25453 certificate names, run @code{certbot certificates}.
25455 Its default is the first provided domain.
25457 @item @code{domains} (default: @code{()})
25458 The first domain provided will be the subject CN of the certificate, and
25459 all domains will be Subject Alternative Names on the certificate.
25461 @item @code{challenge} (default: @code{#f})
25462 The challenge type that has to be run by certbot. If @code{#f} is specified,
25463 default to the HTTP challenge. If a value is specified, defaults to the
25464 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
25465 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
25466 and gives Let's Encrypt permission to log the public IP address of the
25467 requesting machine.
25469 @item @code{authentication-hook} (default: @code{#f})
25470 Command to be run in a shell once for each certificate challenge to be
25471 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
25472 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
25473 contains the validation string and @code{$CERTBOT_TOKEN} contains the
25474 file name of the resource requested when performing an HTTP-01 challenge.
25476 @item @code{cleanup-hook} (default: @code{#f})
25477 Command to be run in a shell once for each certificate challenge that
25478 have been answered by the @code{auth-hook}. For this command, the shell
25479 variables available in the @code{auth-hook} script are still available, and
25480 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
25481 of the @code{auth-hook} script.
25483 @item @code{deploy-hook} (default: @code{#f})
25484 Command to be run in a shell once for each successfully issued
25485 certificate. For this command, the shell variable
25486 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
25487 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
25488 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
25489 contain a space-delimited list of renewed certificate domains (for
25490 example, @samp{"example.com www.example.com"}.
25495 For each @code{certificate-configuration}, the certificate is saved to
25496 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
25497 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
25499 @subsection DNS Services
25500 @cindex DNS (domain name system)
25501 @cindex domain name system (DNS)
25503 The @code{(gnu services dns)} module provides services related to the
25504 @dfn{domain name system} (DNS). It provides a server service for hosting
25505 an @emph{authoritative} DNS server for multiple zones, slave or master.
25506 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
25507 caching and forwarding DNS server for the LAN, which uses
25508 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
25510 @subsubheading Knot Service
25512 An example configuration of an authoritative server for two zones, one master
25516 (define-zone-entries example.org.zone
25517 ;; Name TTL Class Type Data
25518 ("@@" "" "IN" "A" "127.0.0.1")
25519 ("@@" "" "IN" "NS" "ns")
25520 ("ns" "" "IN" "A" "127.0.0.1"))
25522 (define master-zone
25523 (knot-zone-configuration
25524 (domain "example.org")
25526 (origin "example.org")
25527 (entries example.org.zone)))))
25530 (knot-zone-configuration
25531 (domain "plop.org")
25532 (dnssec-policy "default")
25533 (master (list "plop-master"))))
25535 (define plop-master
25536 (knot-remote-configuration
25538 (address (list "208.76.58.171"))))
25542 (services (cons* (service knot-service-type
25543 (knot-configuration
25544 (remotes (list plop-master))
25545 (zones (list master-zone slave-zone))))
25550 @deffn {Scheme Variable} knot-service-type
25551 This is the type for the Knot DNS server.
25553 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
25554 zones, that is to say domain names you would buy from a registrar. This server
25555 is not a resolver, meaning that it can only resolve names for which it is
25556 authoritative. This server can be configured to serve zones as a master server
25557 or a slave server as a per-zone basis. Slave zones will get their data from
25558 masters, and will serve it as an authoritative server. From the point of view
25559 of a resolver, there is no difference between master and slave.
25561 The following data types are used to configure the Knot DNS server:
25564 @deftp {Data Type} knot-key-configuration
25565 Data type representing a key.
25566 This type has the following parameters:
25569 @item @code{id} (default: @code{""})
25570 An identifier for other configuration fields to refer to this key. IDs must
25571 be unique and must not be empty.
25573 @item @code{algorithm} (default: @code{#f})
25574 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
25575 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
25576 and @code{'hmac-sha512}.
25578 @item @code{secret} (default: @code{""})
25579 The secret key itself.
25584 @deftp {Data Type} knot-acl-configuration
25585 Data type representing an Access Control List (ACL) configuration.
25586 This type has the following parameters:
25589 @item @code{id} (default: @code{""})
25590 An identifier for other configuration fields to refer to this key. IDs must be
25591 unique and must not be empty.
25593 @item @code{address} (default: @code{'()})
25594 An ordered list of IP addresses, network subnets, or network ranges represented
25595 with strings. The query must match one of them. Empty value means that
25596 address match is not required.
25598 @item @code{key} (default: @code{'()})
25599 An ordered list of references to keys represented with strings. The string
25600 must match a key ID defined in a @code{knot-key-configuration}. No key means
25601 that a key is not require to match that ACL.
25603 @item @code{action} (default: @code{'()})
25604 An ordered list of actions that are permitted or forbidden by this ACL@. Possible
25605 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
25606 and @code{'update}.
25608 @item @code{deny?} (default: @code{#f})
25609 When true, the ACL defines restrictions. Listed actions are forbidden. When
25610 false, listed actions are allowed.
25615 @deftp {Data Type} zone-entry
25616 Data type representing a record entry in a zone file.
25617 This type has the following parameters:
25620 @item @code{name} (default: @code{"@@"})
25621 The name of the record. @code{"@@"} refers to the origin of the zone. Names
25622 are relative to the origin of the zone. For example, in the @code{example.org}
25623 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
25624 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
25625 refers to @code{ns.example.org}.
25627 @item @code{ttl} (default: @code{""})
25628 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
25630 @item @code{class} (default: @code{"IN"})
25631 The class of the record. Knot currently supports only @code{"IN"} and
25632 partially @code{"CH"}.
25634 @item @code{type} (default: @code{"A"})
25635 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
25636 address), NS (Name Server) and MX (Mail eXchange). Many other types are
25639 @item @code{data} (default: @code{""})
25640 The data contained in the record. For instance an IP address associated with
25641 an A record, or a domain name associated with an NS record. Remember that
25642 domain names are relative to the origin unless they end with a dot.
25647 @deftp {Data Type} zone-file
25648 Data type representing the content of a zone file.
25649 This type has the following parameters:
25652 @item @code{entries} (default: @code{'()})
25653 The list of entries. The SOA record is taken care of, so you don't need to
25654 put it in the list of entries. This list should probably contain an entry
25655 for your primary authoritative DNS server. Other than using a list of entries
25656 directly, you can use @code{define-zone-entries} to define a object containing
25657 the list of entries more easily, that you can later pass to the @code{entries}
25658 field of the @code{zone-file}.
25660 @item @code{origin} (default: @code{""})
25661 The name of your zone. This parameter cannot be empty.
25663 @item @code{ns} (default: @code{"ns"})
25664 The domain of your primary authoritative DNS server. The name is relative to
25665 the origin, unless it ends with a dot. It is mandatory that this primary
25666 DNS server corresponds to an NS record in the zone and that it is associated
25667 to an IP address in the list of entries.
25669 @item @code{mail} (default: @code{"hostmaster"})
25670 An email address people can contact you at, as the owner of the zone. This
25671 is translated as @code{<mail>@@<origin>}.
25673 @item @code{serial} (default: @code{1})
25674 The serial number of the zone. As this is used to keep track of changes by
25675 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
25676 Always increment it when you make a change in your zone.
25678 @item @code{refresh} (default: @code{(* 2 24 3600)})
25679 The frequency at which slaves will do a zone transfer. This value is a number
25680 of seconds. It can be computed by multiplications or with
25681 @code{(string->duration)}.
25683 @item @code{retry} (default: @code{(* 15 60)})
25684 The period after which a slave will retry to contact its master when it fails
25685 to do so a first time.
25687 @item @code{expiry} (default: @code{(* 14 24 3600)})
25688 Default TTL of records. Existing records are considered correct for at most
25689 this amount of time. After this period, resolvers will invalidate their cache
25690 and check again that it still exists.
25692 @item @code{nx} (default: @code{3600})
25693 Default TTL of inexistant records. This delay is usually short because you want
25694 your new domains to reach everyone quickly.
25699 @deftp {Data Type} knot-remote-configuration
25700 Data type representing a remote configuration.
25701 This type has the following parameters:
25704 @item @code{id} (default: @code{""})
25705 An identifier for other configuration fields to refer to this remote. IDs must
25706 be unique and must not be empty.
25708 @item @code{address} (default: @code{'()})
25709 An ordered list of destination IP addresses. Addresses are tried in sequence.
25710 An optional port can be given with the @@ separator. For instance:
25711 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
25713 @item @code{via} (default: @code{'()})
25714 An ordered list of source IP addresses. An empty list will have Knot choose
25715 an appropriate source IP@. An optional port can be given with the @@ separator.
25716 The default is to choose at random.
25718 @item @code{key} (default: @code{#f})
25719 A reference to a key, that is a string containing the identifier of a key
25720 defined in a @code{knot-key-configuration} field.
25725 @deftp {Data Type} knot-keystore-configuration
25726 Data type representing a keystore to hold dnssec keys.
25727 This type has the following parameters:
25730 @item @code{id} (default: @code{""})
25731 The id of the keystore. It must not be empty.
25733 @item @code{backend} (default: @code{'pem})
25734 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
25736 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
25737 The configuration string of the backend. An example for the PKCS#11 is:
25738 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
25739 For the pem backend, the string represents a path in the file system.
25744 @deftp {Data Type} knot-policy-configuration
25745 Data type representing a dnssec policy. Knot DNS is able to automatically
25746 sign your zones. It can either generate and manage your keys automatically or
25747 use keys that you generate.
25749 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
25750 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
25751 zone. In order to be trusted, the KSK needs to be present in the parent zone
25752 (usually a top-level domain). If your registrar supports dnssec, you will
25753 have to send them your KSK's hash so they can add a DS record in their zone.
25754 This is not automated and need to be done each time you change your KSK.
25756 The policy also defines the lifetime of keys. Usually, ZSK can be changed
25757 easily and use weaker cryptographic functions (they use lower parameters) in
25758 order to sign records quickly, so they are changed often. The KSK however
25759 requires manual interaction with the registrar, so they are changed less often
25760 and use stronger parameters because they sign only one record.
25762 This type has the following parameters:
25765 @item @code{id} (default: @code{""})
25766 The id of the policy. It must not be empty.
25768 @item @code{keystore} (default: @code{"default"})
25769 A reference to a keystore, that is a string containing the identifier of a
25770 keystore defined in a @code{knot-keystore-configuration} field. The
25771 @code{"default"} identifier means the default keystore (a kasp database that
25772 was setup by this service).
25774 @item @code{manual?} (default: @code{#f})
25775 Whether the key management is manual or automatic.
25777 @item @code{single-type-signing?} (default: @code{#f})
25778 When @code{#t}, use the Single-Type Signing Scheme.
25780 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
25781 An algorithm of signing keys and issued signatures.
25783 @item @code{ksk-size} (default: @code{256})
25784 The length of the KSK@. Note that this value is correct for the default
25785 algorithm, but would be unsecure for other algorithms.
25787 @item @code{zsk-size} (default: @code{256})
25788 The length of the ZSK@. Note that this value is correct for the default
25789 algorithm, but would be unsecure for other algorithms.
25791 @item @code{dnskey-ttl} (default: @code{'default})
25792 The TTL value for DNSKEY records added into zone apex. The special
25793 @code{'default} value means same as the zone SOA TTL.
25795 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
25796 The period between ZSK publication and the next rollover initiation.
25798 @item @code{propagation-delay} (default: @code{(* 24 3600)})
25799 An extra delay added for each key rollover step. This value should be high
25800 enough to cover propagation of data from the master server to all slaves.
25802 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
25803 A validity period of newly issued signatures.
25805 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
25806 A period how long before a signature expiration the signature will be refreshed.
25808 @item @code{nsec3?} (default: @code{#f})
25809 When @code{#t}, NSEC3 will be used instead of NSEC.
25811 @item @code{nsec3-iterations} (default: @code{5})
25812 The number of additional times the hashing is performed.
25814 @item @code{nsec3-salt-length} (default: @code{8})
25815 The length of a salt field in octets, which is appended to the original owner
25816 name before hashing.
25818 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
25819 The validity period of newly issued salt field.
25824 @deftp {Data Type} knot-zone-configuration
25825 Data type representing a zone served by Knot.
25826 This type has the following parameters:
25829 @item @code{domain} (default: @code{""})
25830 The domain served by this configuration. It must not be empty.
25832 @item @code{file} (default: @code{""})
25833 The file where this zone is saved. This parameter is ignored by master zones.
25834 Empty means default location that depends on the domain name.
25836 @item @code{zone} (default: @code{(zone-file)})
25837 The content of the zone file. This parameter is ignored by slave zones. It
25838 must contain a zone-file record.
25840 @item @code{master} (default: @code{'()})
25841 A list of master remotes. When empty, this zone is a master. When set, this
25842 zone is a slave. This is a list of remotes identifiers.
25844 @item @code{ddns-master} (default: @code{#f})
25845 The main master. When empty, it defaults to the first master in the list of
25848 @item @code{notify} (default: @code{'()})
25849 A list of slave remote identifiers.
25851 @item @code{acl} (default: @code{'()})
25852 A list of acl identifiers.
25854 @item @code{semantic-checks?} (default: @code{#f})
25855 When set, this adds more semantic checks to the zone.
25857 @item @code{disable-any?} (default: @code{#f})
25858 When set, this forbids queries of the ANY type.
25860 @item @code{zonefile-sync} (default: @code{0})
25861 The delay between a modification in memory and on disk. 0 means immediate
25864 @item @code{zonefile-load} (default: @code{#f})
25865 The way the zone file contents are applied during zone load. Possible values
25869 @item @code{#f} for using the default value from Knot,
25870 @item @code{'none} for not using the zone file at all,
25871 @item @code{'difference} for computing the difference between already available
25872 contents and zone contents and applying it to the current zone contents,
25873 @item @code{'difference-no-serial} for the same as @code{'difference}, but
25874 ignoring the SOA serial in the zone file, while the server takes care of it
25876 @item @code{'whole} for loading zone contents from the zone file.
25879 @item @code{journal-content} (default: @code{#f})
25880 The way the journal is used to store zone and its changes. Possible values
25881 are @code{'none} to not use it at all, @code{'changes} to store changes and
25882 @code{'all} to store contents. @code{#f} does not set this option, so the
25883 default value from Knot is used.
25885 @item @code{max-journal-usage} (default: @code{#f})
25886 The maximum size for the journal on disk. @code{#f} does not set this option,
25887 so the default value from Knot is used.
25889 @item @code{max-journal-depth} (default: @code{#f})
25890 The maximum size of the history. @code{#f} does not set this option, so the
25891 default value from Knot is used.
25893 @item @code{max-zone-size} (default: @code{#f})
25894 The maximum size of the zone file. This limit is enforced for incoming
25895 transfer and updates. @code{#f} does not set this option, so the default
25896 value from Knot is used.
25898 @item @code{dnssec-policy} (default: @code{#f})
25899 A reference to a @code{knot-policy-configuration} record, or the special
25900 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
25903 @item @code{serial-policy} (default: @code{'increment})
25904 A policy between @code{'increment} and @code{'unixtime}.
25909 @deftp {Data Type} knot-configuration
25910 Data type representing the Knot configuration.
25911 This type has the following parameters:
25914 @item @code{knot} (default: @code{knot})
25917 @item @code{run-directory} (default: @code{"/var/run/knot"})
25918 The run directory. This directory will be used for pid file and sockets.
25920 @item @code{includes} (default: @code{'()})
25921 A list of strings or file-like objects denoting other files that must be
25922 included at the top of the configuration file.
25924 @cindex secrets, Knot service
25925 This can be used to manage secrets out-of-band. For example, secret
25926 keys may be stored in an out-of-band file not managed by Guix, and
25927 thus not visible in @file{/gnu/store}---e.g., you could store secret
25928 key configuration in @file{/etc/knot/secrets.conf} and add this file
25929 to the @code{includes} list.
25931 One can generate a secret tsig key (for nsupdate and zone transfers with the
25932 keymgr command from the knot package. Note that the package is not automatically
25933 installed by the service. The following example shows how to generate a new
25937 keymgr -t mysecret > /etc/knot/secrets.conf
25938 chmod 600 /etc/knot/secrets.conf
25941 Also note that the generated key will be named @var{mysecret}, so it is the
25942 name that needs to be used in the @var{key} field of the
25943 @code{knot-acl-configuration} record and in other places that need to refer
25946 It can also be used to add configuration not supported by this interface.
25948 @item @code{listen-v4} (default: @code{"0.0.0.0"})
25949 An ip address on which to listen.
25951 @item @code{listen-v6} (default: @code{"::"})
25952 An ip address on which to listen.
25954 @item @code{listen-port} (default: @code{53})
25955 A port on which to listen.
25957 @item @code{keys} (default: @code{'()})
25958 The list of knot-key-configuration used by this configuration.
25960 @item @code{acls} (default: @code{'()})
25961 The list of knot-acl-configuration used by this configuration.
25963 @item @code{remotes} (default: @code{'()})
25964 The list of knot-remote-configuration used by this configuration.
25966 @item @code{zones} (default: @code{'()})
25967 The list of knot-zone-configuration used by this configuration.
25972 @subsubheading Knot Resolver Service
25974 @deffn {Scheme Variable} knot-resolver-service-type
25975 This is the type of the knot resolver service, whose value should be
25976 an @code{knot-resolver-configuration} object as in this example:
25979 (service knot-resolver-service-type
25980 (knot-resolver-configuration
25981 (kresd-config-file (plain-file "kresd.conf" "
25982 net.listen('192.168.0.1', 5353)
25983 user('knot-resolver', 'knot-resolver')
25984 modules = @{ 'hints > iterate', 'stats', 'predict' @}
25985 cache.size = 100 * MB
25989 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
25992 @deftp {Data Type} knot-resolver-configuration
25993 Data type representing the configuration of knot-resolver.
25996 @item @code{package} (default: @var{knot-resolver})
25997 Package object of the knot DNS resolver.
25999 @item @code{kresd-config-file} (default: %kresd.conf)
26000 File-like object of the kresd configuration file to use, by default it
26001 will listen on @code{127.0.0.1} and @code{::1}.
26003 @item @code{garbage-collection-interval} (default: 1000)
26004 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
26010 @subsubheading Dnsmasq Service
26012 @deffn {Scheme Variable} dnsmasq-service-type
26013 This is the type of the dnsmasq service, whose value should be an
26014 @code{dnsmasq-configuration} object as in this example:
26017 (service dnsmasq-service-type
26018 (dnsmasq-configuration
26020 (servers '("192.168.1.1"))))
26024 @deftp {Data Type} dnsmasq-configuration
26025 Data type representing the configuration of dnsmasq.
26028 @item @code{package} (default: @var{dnsmasq})
26029 Package object of the dnsmasq server.
26031 @item @code{no-hosts?} (default: @code{#f})
26032 When true, don't read the hostnames in /etc/hosts.
26034 @item @code{port} (default: @code{53})
26035 The port to listen on. Setting this to zero completely disables DNS
26036 responses, leaving only DHCP and/or TFTP functions.
26038 @item @code{local-service?} (default: @code{#t})
26039 Accept DNS queries only from hosts whose address is on a local subnet,
26040 ie a subnet for which an interface exists on the server.
26042 @item @code{listen-addresses} (default: @code{'()})
26043 Listen on the given IP addresses.
26045 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
26046 The file to read the IP address of the upstream nameservers from.
26048 @item @code{no-resolv?} (default: @code{#f})
26049 When true, don't read @var{resolv-file}.
26051 @item @code{servers} (default: @code{'()})
26052 Specify IP address of upstream servers directly.
26054 @item @code{addresses} (default: @code{'()})
26055 For each entry, specify an IP address to return for any host in the
26056 given domains. Queries in the domains are never forwarded and always
26057 replied to with the specified IP address.
26059 This is useful for redirecting hosts locally, for example:
26062 (service dnsmasq-service-type
26063 (dnsmasq-configuration
26065 '(; Redirect to a local web-server.
26066 "/example.org/127.0.0.1"
26067 ; Redirect subdomain to a specific IP.
26068 "/subdomain.example.org/192.168.1.42"))))
26071 Note that rules in @file{/etc/hosts} take precedence over this.
26073 @item @code{cache-size} (default: @code{150})
26074 Set the size of dnsmasq's cache. Setting the cache size to zero
26077 @item @code{negative-cache?} (default: @code{#t})
26078 When false, disable negative caching.
26080 @item @code{tftp-enable?} (default: @code{#f})
26081 Whether to enable the built-in TFTP server.
26083 @item @code{tftp-no-fail?} (default: @code{#f})
26084 If true, does not fail dnsmasq if the TFTP server could not start up.
26086 @item @code{tftp-single-port?} (default: @code{#f})
26087 Whether to use only one single port for TFTP.
26089 @item @code{tftp-secure?} (default: @code{#f})
26090 If true, only files owned by the user running the dnsmasq process are accessible.
26092 If dnsmasq is being run as root, different rules apply:
26093 @code{tftp-secure?} has no effect, but only files which have the
26094 world-readable bit set are accessible.
26096 @item @code{tftp-max} (default: @code{#f})
26097 If set, sets the maximal number of concurrent connections allowed.
26099 @item @code{tftp-mtu} (default: @code{#f})
26100 If set, sets the MTU for TFTP packets to that value.
26102 @item @code{tftp-no-blocksize?} (default: @code{#f})
26103 If true, stops the TFTP server from negotiating the blocksize with a client.
26105 @item @code{tftp-lowercase?} (default: @code{#f})
26106 Whether to convert all filenames in TFTP requests to lowercase.
26108 @item @code{tftp-port-range} (default: @code{#f})
26109 If set, fixes the dynamical ports (one per client) to the given range
26110 (@code{"<start>,<end>"}).
26112 @item @code{tftp-root} (default: @code{/var/empty,lo})
26113 Look for files to transfer using TFTP relative to the given directory.
26114 When this is set, TFTP paths which include @samp{..} are rejected, to stop clients
26115 getting outside the specified root. Absolute paths (starting with @samp{/}) are
26116 allowed, but they must be within the TFTP-root. If the optional interface
26117 argument is given, the directory is only used for TFTP requests via that
26120 @item @code{tftp-unique-root} (default: @code{#f})
26121 If set, add the IP or hardware address of the TFTP client as a path component
26122 on the end of the TFTP-root. Only valid if a TFTP root is set and the
26123 directory exists. Defaults to adding IP address (in standard dotted-quad
26126 For instance, if @option{--tftp-root} is @samp{/tftp} and client
26127 @samp{1.2.3.4} requests file @file{myfile} then the effective path will
26128 be @file{/tftp/1.2.3.4/myfile} if @file{/tftp/1.2.3.4} exists or
26129 @file{/tftp/myfile} otherwise. When @samp{=mac} is specified it will
26130 append the MAC address instead, using lowercase zero padded digits
26131 separated by dashes, e.g.: @samp{01-02-03-04-aa-bb}. Note that
26132 resolving MAC addresses is only possible if the client is in the local
26133 network or obtained a DHCP lease from dnsmasq.
26138 @subsubheading ddclient Service
26141 The ddclient service described below runs the ddclient daemon, which takes
26142 care of automatically updating DNS entries for service providers such as
26143 @uref{https://dyn.com/dns/, Dyn}.
26145 The following example show instantiates the service with its default
26149 (service ddclient-service-type)
26152 Note that ddclient needs to access credentials that are stored in a
26153 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
26154 @code{secret-file} below). You are expected to create this file manually, in
26155 an ``out-of-band'' fashion (you @emph{could} make this file part of the
26156 service configuration, for instance by using @code{plain-file}, but it will be
26157 world-readable @i{via} @file{/gnu/store}). See the examples in the
26158 @file{share/ddclient} directory of the @code{ddclient} package.
26160 @c %start of fragment
26162 Available @code{ddclient-configuration} fields are:
26164 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
26165 The ddclient package.
26169 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
26170 The period after which ddclient will retry to check IP and domain name.
26172 Defaults to @samp{300}.
26176 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
26177 Use syslog for the output.
26179 Defaults to @samp{#t}.
26183 @deftypevr {@code{ddclient-configuration} parameter} string mail
26186 Defaults to @samp{"root"}.
26190 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
26191 Mail failed update to user.
26193 Defaults to @samp{"root"}.
26197 @deftypevr {@code{ddclient-configuration} parameter} string pid
26198 The ddclient PID file.
26200 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
26204 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
26205 Enable SSL support.
26207 Defaults to @samp{#t}.
26211 @deftypevr {@code{ddclient-configuration} parameter} string user
26212 Specifies the user name or ID that is used when running ddclient
26215 Defaults to @samp{"ddclient"}.
26219 @deftypevr {@code{ddclient-configuration} parameter} string group
26220 Group of the user who will run the ddclient program.
26222 Defaults to @samp{"ddclient"}.
26226 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
26227 Secret file which will be appended to @file{ddclient.conf} file. This
26228 file contains credentials for use by ddclient. You are expected to
26229 create it manually.
26231 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
26235 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
26236 Extra options will be appended to @file{ddclient.conf} file.
26238 Defaults to @samp{()}.
26243 @c %end of fragment
26247 @subsection VPN Services
26248 @cindex VPN (virtual private network)
26249 @cindex virtual private network (VPN)
26251 The @code{(gnu services vpn)} module provides services related to
26252 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
26253 your machine to connect to a VPN, and a @emph{server} service for your machine
26254 to host a VPN@. Both services use @uref{https://openvpn.net/, OpenVPN}.
26256 @deffn {Scheme Procedure} openvpn-client-service @
26257 [#:config (openvpn-client-configuration)]
26259 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
26262 @deffn {Scheme Procedure} openvpn-server-service @
26263 [#:config (openvpn-server-configuration)]
26265 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
26267 Both can be run simultaneously.
26270 @c %automatically generated documentation
26272 Available @code{openvpn-client-configuration} fields are:
26274 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
26275 The OpenVPN package.
26279 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
26280 The OpenVPN pid file.
26282 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
26286 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
26287 The protocol (UDP or TCP) used to open a channel between clients and
26290 Defaults to @samp{udp}.
26294 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
26295 The device type used to represent the VPN connection.
26297 Defaults to @samp{tun}.
26301 If you do not have some of these files (eg.@: you use a username and
26302 password), you can disable any of the following three fields by setting
26303 it to @code{'disabled}.
26305 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string ca
26306 The certificate authority to check connections against.
26308 Defaults to @samp{"/etc/openvpn/ca.crt"}.
26312 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string cert
26313 The certificate of the machine the daemon is running on. It should be
26314 signed by the authority given in @code{ca}.
26316 Defaults to @samp{"/etc/openvpn/client.crt"}.
26320 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string key
26321 The key of the machine the daemon is running on. It must be the key whose
26322 certificate is @code{cert}.
26324 Defaults to @samp{"/etc/openvpn/client.key"}.
26328 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
26329 Whether to use the lzo compression algorithm.
26331 Defaults to @samp{#t}.
26335 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
26336 Don't re-read key files across SIGUSR1 or --ping-restart.
26338 Defaults to @samp{#t}.
26342 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
26343 Don't close and reopen TUN/TAP device or run up/down scripts across
26344 SIGUSR1 or --ping-restart restarts.
26346 Defaults to @samp{#t}.
26350 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
26351 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
26352 poll/epoll/select prior to the write operation.
26354 Defaults to @samp{#f}.
26357 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
26360 Defaults to @samp{3}.
26364 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
26365 Add an additional layer of HMAC authentication on top of the TLS control
26366 channel to protect against DoS attacks.
26368 Defaults to @samp{#f}.
26372 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
26373 Authenticate with server using username/password. The option is a file
26374 containing username/password on 2 lines. Do not use a file-like object as it
26375 would be added to the store and readable by any user.
26377 Defaults to @samp{'disabled}.
26380 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
26381 Whether to check the server certificate has server usage extension.
26383 Defaults to @samp{#t}.
26387 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
26388 Bind to a specific local port number.
26390 Defaults to @samp{#f}.
26394 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
26395 Retry resolving server address.
26397 Defaults to @samp{#t}.
26401 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
26402 A list of remote servers to connect to.
26404 Defaults to @samp{()}.
26406 Available @code{openvpn-remote-configuration} fields are:
26408 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
26411 Defaults to @samp{"my-server"}.
26415 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
26416 Port number the server listens to.
26418 Defaults to @samp{1194}.
26423 @c %end of automatic openvpn-client documentation
26425 @c %automatically generated documentation
26427 Available @code{openvpn-server-configuration} fields are:
26429 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
26430 The OpenVPN package.
26434 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
26435 The OpenVPN pid file.
26437 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
26441 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
26442 The protocol (UDP or TCP) used to open a channel between clients and
26445 Defaults to @samp{udp}.
26449 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
26450 The device type used to represent the VPN connection.
26452 Defaults to @samp{tun}.
26456 If you do not have some of these files (eg.@: you use a username and
26457 password), you can disable any of the following three fields by setting
26458 it to @code{'disabled}.
26460 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string ca
26461 The certificate authority to check connections against.
26463 Defaults to @samp{"/etc/openvpn/ca.crt"}.
26467 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string cert
26468 The certificate of the machine the daemon is running on. It should be
26469 signed by the authority given in @code{ca}.
26471 Defaults to @samp{"/etc/openvpn/client.crt"}.
26475 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string key
26476 The key of the machine the daemon is running on. It must be the key whose
26477 certificate is @code{cert}.
26479 Defaults to @samp{"/etc/openvpn/client.key"}.
26483 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
26484 Whether to use the lzo compression algorithm.
26486 Defaults to @samp{#t}.
26490 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
26491 Don't re-read key files across SIGUSR1 or --ping-restart.
26493 Defaults to @samp{#t}.
26497 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
26498 Don't close and reopen TUN/TAP device or run up/down scripts across
26499 SIGUSR1 or --ping-restart restarts.
26501 Defaults to @samp{#t}.
26505 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
26506 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
26507 poll/epoll/select prior to the write operation.
26509 Defaults to @samp{#f}.
26512 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
26515 Defaults to @samp{3}.
26519 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
26520 Add an additional layer of HMAC authentication on top of the TLS control
26521 channel to protect against DoS attacks.
26523 Defaults to @samp{#f}.
26527 @deftypevr {@code{openvpn-server-configuration} parameter} number port
26528 Specifies the port number on which the server listens.
26530 Defaults to @samp{1194}.
26534 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
26535 An ip and mask specifying the subnet inside the virtual network.
26537 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
26541 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
26542 A CIDR notation specifying the IPv6 subnet inside the virtual network.
26544 Defaults to @samp{#f}.
26548 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
26549 The Diffie-Hellman parameters file.
26551 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
26555 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
26556 The file that records client IPs.
26558 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
26562 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
26563 When true, the server will act as a gateway for its clients.
26565 Defaults to @samp{#f}.
26569 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
26570 When true, clients are allowed to talk to each other inside the VPN.
26572 Defaults to @samp{#f}.
26576 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
26577 Causes ping-like messages to be sent back and forth over the link so
26578 that each side knows when the other side has gone down. @code{keepalive}
26579 requires a pair. The first element is the period of the ping sending,
26580 and the second element is the timeout before considering the other side
26585 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
26586 The maximum number of clients.
26588 Defaults to @samp{100}.
26592 @deftypevr {@code{openvpn-server-configuration} parameter} string status
26593 The status file. This file shows a small report on current connection.
26594 It is truncated and rewritten every minute.
26596 Defaults to @samp{"/var/run/openvpn/status"}.
26600 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
26601 The list of configuration for some clients.
26603 Defaults to @samp{()}.
26605 Available @code{openvpn-ccd-configuration} fields are:
26607 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
26610 Defaults to @samp{"client"}.
26614 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
26617 Defaults to @samp{#f}.
26621 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
26624 Defaults to @samp{#f}.
26631 @c %end of automatic openvpn-server documentation
26634 @node Network File System
26635 @subsection Network File System
26638 The @code{(gnu services nfs)} module provides the following services,
26639 which are most commonly used in relation to mounting or exporting
26640 directory trees as @dfn{network file systems} (NFS).
26642 While it is possible to use the individual components that together make
26643 up a Network File System service, we recommended to configure an NFS
26644 server with the @code{nfs-service-type}.
26646 @subsubheading NFS Service
26647 @cindex NFS, server
26649 The NFS service takes care of setting up all NFS component services,
26650 kernel configuration file systems, and installs configuration files in
26651 the locations that NFS expects.
26653 @defvr {Scheme Variable} nfs-service-type
26654 A service type for a complete NFS server.
26657 @deftp {Data Type} nfs-configuration
26658 This data type represents the configuration of the NFS service and all
26661 It has the following parameters:
26663 @item @code{nfs-utils} (default: @code{nfs-utils})
26664 The nfs-utils package to use.
26666 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
26667 If a list of string values is provided, the @command{rpc.nfsd} daemon
26668 will be limited to supporting the given versions of the NFS protocol.
26670 @item @code{exports} (default: @code{'()})
26671 This is a list of directories the NFS server should export. Each entry
26672 is a list consisting of two elements: a directory name and a string
26673 containing all options. This is an example in which the directory
26674 @file{/export} is served to all NFS clients as a read-only share:
26680 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
26683 @item @code{rpcmountd-port} (default: @code{#f})
26684 The network port that the @command{rpc.mountd} daemon should use.
26686 @item @code{rpcstatd-port} (default: @code{#f})
26687 The network port that the @command{rpc.statd} daemon should use.
26689 @item @code{rpcbind} (default: @code{rpcbind})
26690 The rpcbind package to use.
26692 @item @code{idmap-domain} (default: @code{"localdomain"})
26693 The local NFSv4 domain name.
26695 @item @code{nfsd-port} (default: @code{2049})
26696 The network port that the @command{nfsd} daemon should use.
26698 @item @code{nfsd-threads} (default: @code{8})
26699 The number of threads used by the @command{nfsd} daemon.
26701 @item @code{nfsd-tcp?} (default: @code{#t})
26702 Whether the @command{nfsd} daemon should listen on a TCP socket.
26704 @item @code{nfsd-udp?} (default: @code{#f})
26705 Whether the @command{nfsd} daemon should listen on a UDP socket.
26707 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
26708 The directory where the pipefs file system is mounted.
26710 @item @code{debug} (default: @code{'()"})
26711 A list of subsystems for which debugging output should be enabled. This
26712 is a list of symbols. Any of these symbols are valid: @code{nfsd},
26713 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
26717 If you don't need a complete NFS service or prefer to build it yourself
26718 you can use the individual component services that are documented below.
26720 @subsubheading RPC Bind Service
26723 The RPC Bind service provides a facility to map program numbers into
26724 universal addresses.
26725 Many NFS related services use this facility. Hence it is automatically
26726 started when a dependent service starts.
26728 @defvr {Scheme Variable} rpcbind-service-type
26729 A service type for the RPC portmapper daemon.
26733 @deftp {Data Type} rpcbind-configuration
26734 Data type representing the configuration of the RPC Bind Service.
26735 This type has the following parameters:
26737 @item @code{rpcbind} (default: @code{rpcbind})
26738 The rpcbind package to use.
26740 @item @code{warm-start?} (default: @code{#t})
26741 If this parameter is @code{#t}, then the daemon will read a
26742 state file on startup thus reloading state information saved by a previous
26748 @subsubheading Pipefs Pseudo File System
26752 The pipefs file system is used to transfer NFS related data
26753 between the kernel and user space programs.
26755 @defvr {Scheme Variable} pipefs-service-type
26756 A service type for the pipefs pseudo file system.
26759 @deftp {Data Type} pipefs-configuration
26760 Data type representing the configuration of the pipefs pseudo file system service.
26761 This type has the following parameters:
26763 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
26764 The directory to which the file system is to be attached.
26769 @subsubheading GSS Daemon Service
26772 @cindex global security system
26774 The @dfn{global security system} (GSS) daemon provides strong security for RPC
26776 Before exchanging RPC requests an RPC client must establish a security
26777 context. Typically this is done using the Kerberos command @command{kinit}
26778 or automatically at login time using PAM services (@pxref{Kerberos Services}).
26780 @defvr {Scheme Variable} gss-service-type
26781 A service type for the Global Security System (GSS) daemon.
26784 @deftp {Data Type} gss-configuration
26785 Data type representing the configuration of the GSS daemon service.
26786 This type has the following parameters:
26788 @item @code{nfs-utils} (default: @code{nfs-utils})
26789 The package in which the @command{rpc.gssd} command is to be found.
26791 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
26792 The directory where the pipefs file system is mounted.
26798 @subsubheading IDMAP Daemon Service
26800 @cindex name mapper
26802 The idmap daemon service provides mapping between user IDs and user names.
26803 Typically it is required in order to access file systems mounted via NFSv4.
26805 @defvr {Scheme Variable} idmap-service-type
26806 A service type for the Identity Mapper (IDMAP) daemon.
26809 @deftp {Data Type} idmap-configuration
26810 Data type representing the configuration of the IDMAP daemon service.
26811 This type has the following parameters:
26813 @item @code{nfs-utils} (default: @code{nfs-utils})
26814 The package in which the @command{rpc.idmapd} command is to be found.
26816 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
26817 The directory where the pipefs file system is mounted.
26819 @item @code{domain} (default: @code{#f})
26820 The local NFSv4 domain name.
26821 This must be a string or @code{#f}.
26822 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
26824 @item @code{verbosity} (default: @code{0})
26825 The verbosity level of the daemon.
26830 @node Continuous Integration
26831 @subsection Continuous Integration
26833 @cindex continuous integration
26834 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
26835 continuous integration tool for Guix. It can be used both for development and
26836 for providing substitutes to others (@pxref{Substitutes}).
26838 The @code{(gnu services cuirass)} module provides the following service.
26840 @defvr {Scheme Procedure} cuirass-service-type
26841 The type of the Cuirass service. Its value must be a
26842 @code{cuirass-configuration} object, as described below.
26845 To add build jobs, you have to set the @code{specifications} field of the
26846 configuration. Here is an example of a service that polls the Guix repository
26847 and builds the packages from a manifest. Some of the packages are defined in
26848 the @code{"custom-packages"} input, which is the equivalent of
26849 @env{GUIX_PACKAGE_PATH}.
26852 (define %cuirass-specs
26854 '((#:name . "my-manifest")
26855 (#:load-path-inputs . ("guix"))
26856 (#:package-path-inputs . ("custom-packages"))
26857 (#:proc-input . "guix")
26858 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
26859 (#:proc . cuirass-jobs)
26860 (#:proc-args . ((subset . "manifests")
26861 (systems . ("x86_64-linux"))
26862 (manifests . (("config" . "guix/manifest.scm")))))
26863 (#:inputs . (((#:name . "guix")
26864 (#:url . "git://git.savannah.gnu.org/guix.git")
26865 (#:load-path . ".")
26866 (#:branch . "master")
26867 (#:no-compile? . #t))
26868 ((#:name . "config")
26869 (#:url . "https://git.example.org/config.git")
26870 (#:load-path . ".")
26871 (#:branch . "master")
26872 (#:no-compile? . #t))
26873 ((#:name . "custom-packages")
26874 (#:url . "https://git.example.org/custom-packages.git")
26875 (#:load-path . ".")
26876 (#:branch . "master")
26877 (#:no-compile? . #t)))))))
26879 (service cuirass-service-type
26880 (cuirass-configuration
26881 (specifications %cuirass-specs)))
26884 While information related to build jobs is located directly in the
26885 specifications, global settings for the @command{cuirass} process are
26886 accessible in other @code{cuirass-configuration} fields.
26888 @deftp {Data Type} cuirass-configuration
26889 Data type representing the configuration of Cuirass.
26892 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
26893 Location of the log file.
26895 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
26896 Location of the log file used by the web interface.
26898 @item @code{queries-log-file} (default: @code{#f})
26899 Location of the SQL queries log file. By default, SQL queries logging is
26902 @item @code{web-queries-log-file} (default: @code{#f})
26903 Location of the web SQL queries log file. By default, web SQL queries
26904 logging is disabled.
26906 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
26907 Location of the repository cache.
26909 @item @code{user} (default: @code{"cuirass"})
26910 Owner of the @code{cuirass} process.
26912 @item @code{group} (default: @code{"cuirass"})
26913 Owner's group of the @code{cuirass} process.
26915 @item @code{interval} (default: @code{60})
26916 Number of seconds between the poll of the repositories followed by the
26919 @item @code{queue-size} (default: @code{1})
26920 Size of the database writer queue.
26922 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
26923 Location of sqlite database which contains the build results and previously
26924 added specifications.
26926 @item @code{ttl} (default: @code{(* 30 24 3600)})
26927 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
26928 are registered for build results. This means that build results are protected
26929 from garbage collection for at least @var{ttl} seconds.
26931 @item @code{port} (default: @code{8081})
26932 Port number used by the HTTP server.
26934 @item @code{host} (default: @code{"localhost"})
26935 Listen on the network interface for @var{host}. The default is to
26936 accept connections from localhost.
26938 @item @code{specifications} (default: @code{#~'()})
26939 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
26940 where a specification is an association list
26941 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
26942 keys are keywords (@code{#:keyword-example}) as shown in the example
26945 @item @code{use-substitutes?} (default: @code{#f})
26946 This allows using substitutes to avoid building every dependencies of a job
26949 @item @code{one-shot?} (default: @code{#f})
26950 Only evaluate specifications and build derivations once.
26952 @item @code{fallback?} (default: @code{#f})
26953 When substituting a pre-built binary fails, fall back to building
26956 @item @code{extra-options} (default: @code{'()})
26957 Extra options to pass when running the Cuirass processes.
26959 @item @code{cuirass} (default: @code{cuirass})
26960 The Cuirass package to use.
26964 @node Power Management Services
26965 @subsection Power Management Services
26968 @cindex power management with TLP
26969 @subsubheading TLP daemon
26971 The @code{(gnu services pm)} module provides a Guix service definition
26972 for the Linux power management tool TLP.
26974 TLP enables various powersaving modes in userspace and kernel.
26975 Contrary to @code{upower-service}, it is not a passive,
26976 monitoring tool, as it will apply custom settings each time a new power
26977 source is detected. More information can be found at
26978 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
26980 @deffn {Scheme Variable} tlp-service-type
26981 The service type for the TLP tool. The default settings are optimised
26982 for battery life on most systems, but you can tweak them to your heart's
26983 content by adding a valid @code{tlp-configuration}:
26985 (service tlp-service-type
26987 (cpu-scaling-governor-on-ac (list "performance"))
26988 (sched-powersave-on-bat? #t)))
26992 Each parameter definition is preceded by its type; for example,
26993 @samp{boolean foo} indicates that the @code{foo} parameter
26994 should be specified as a boolean. Types starting with
26995 @code{maybe-} denote parameters that won't show up in TLP config file
26996 when their value is @code{'disabled}.
26998 @c The following documentation was initially generated by
26999 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
27000 @c documentation is better, so we shouldn't hesitate to edit below as
27001 @c needed. However if the change you want to make to this documentation
27002 @c can be done in an automated way, it's probably easier to change
27003 @c (generate-documentation) than to make it below and have to deal with
27004 @c the churn as TLP updates.
27006 Available @code{tlp-configuration} fields are:
27008 @deftypevr {@code{tlp-configuration} parameter} package tlp
27013 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
27014 Set to true if you wish to enable TLP.
27016 Defaults to @samp{#t}.
27020 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
27021 Default mode when no power supply can be detected. Alternatives are AC
27024 Defaults to @samp{"AC"}.
27028 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
27029 Number of seconds Linux kernel has to wait after the disk goes idle,
27030 before syncing on AC.
27032 Defaults to @samp{0}.
27036 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
27037 Same as @code{disk-idle-ac} but on BAT mode.
27039 Defaults to @samp{2}.
27043 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
27044 Dirty pages flushing periodicity, expressed in seconds.
27046 Defaults to @samp{15}.
27050 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
27051 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
27053 Defaults to @samp{60}.
27057 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
27058 CPU frequency scaling governor on AC mode. With intel_pstate driver,
27059 alternatives are powersave and performance. With acpi-cpufreq driver,
27060 alternatives are ondemand, powersave, performance and conservative.
27062 Defaults to @samp{disabled}.
27066 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
27067 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
27069 Defaults to @samp{disabled}.
27073 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
27074 Set the min available frequency for the scaling governor on AC.
27076 Defaults to @samp{disabled}.
27080 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
27081 Set the max available frequency for the scaling governor on AC.
27083 Defaults to @samp{disabled}.
27087 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
27088 Set the min available frequency for the scaling governor on BAT.
27090 Defaults to @samp{disabled}.
27094 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
27095 Set the max available frequency for the scaling governor on BAT.
27097 Defaults to @samp{disabled}.
27101 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
27102 Limit the min P-state to control the power dissipation of the CPU, in AC
27103 mode. Values are stated as a percentage of the available performance.
27105 Defaults to @samp{disabled}.
27109 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
27110 Limit the max P-state to control the power dissipation of the CPU, in AC
27111 mode. Values are stated as a percentage of the available performance.
27113 Defaults to @samp{disabled}.
27117 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
27118 Same as @code{cpu-min-perf-on-ac} on BAT mode.
27120 Defaults to @samp{disabled}.
27124 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
27125 Same as @code{cpu-max-perf-on-ac} on BAT mode.
27127 Defaults to @samp{disabled}.
27131 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
27132 Enable CPU turbo boost feature on AC mode.
27134 Defaults to @samp{disabled}.
27138 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
27139 Same as @code{cpu-boost-on-ac?} on BAT mode.
27141 Defaults to @samp{disabled}.
27145 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
27146 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
27147 used under light load conditions.
27149 Defaults to @samp{#f}.
27153 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
27154 Same as @code{sched-powersave-on-ac?} but on BAT mode.
27156 Defaults to @samp{#t}.
27160 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
27161 Enable Linux kernel NMI watchdog.
27163 Defaults to @samp{#f}.
27167 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
27168 For Linux kernels with PHC patch applied, change CPU voltages. An
27169 example value would be @samp{"F:V F:V F:V F:V"}.
27171 Defaults to @samp{disabled}.
27175 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
27176 Set CPU performance versus energy saving policy on AC@. Alternatives are
27177 performance, normal, powersave.
27179 Defaults to @samp{"performance"}.
27183 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
27184 Same as @code{energy-perf-policy-ac} but on BAT mode.
27186 Defaults to @samp{"powersave"}.
27190 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
27195 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
27196 Hard disk advanced power management level.
27200 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
27201 Same as @code{disk-apm-bat} but on BAT mode.
27205 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
27206 Hard disk spin down timeout. One value has to be specified for each
27207 declared hard disk.
27209 Defaults to @samp{disabled}.
27213 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
27214 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
27216 Defaults to @samp{disabled}.
27220 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
27221 Select IO scheduler for disk devices. One value has to be specified for
27222 each declared hard disk. Example alternatives are cfq, deadline and
27225 Defaults to @samp{disabled}.
27229 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
27230 SATA aggressive link power management (ALPM) level. Alternatives are
27231 min_power, medium_power, max_performance.
27233 Defaults to @samp{"max_performance"}.
27237 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
27238 Same as @code{sata-linkpwr-ac} but on BAT mode.
27240 Defaults to @samp{"min_power"}.
27244 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
27245 Exclude specified SATA host devices for link power management.
27247 Defaults to @samp{disabled}.
27251 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
27252 Enable Runtime Power Management for AHCI controller and disks on AC
27255 Defaults to @samp{disabled}.
27259 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
27260 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
27262 Defaults to @samp{disabled}.
27266 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
27267 Seconds of inactivity before disk is suspended.
27269 Defaults to @samp{15}.
27273 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
27274 PCI Express Active State Power Management level. Alternatives are
27275 default, performance, powersave.
27277 Defaults to @samp{"performance"}.
27281 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
27282 Same as @code{pcie-aspm-ac} but on BAT mode.
27284 Defaults to @samp{"powersave"}.
27288 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
27289 Radeon graphics clock speed level. Alternatives are low, mid, high,
27292 Defaults to @samp{"high"}.
27296 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
27297 Same as @code{radeon-power-ac} but on BAT mode.
27299 Defaults to @samp{"low"}.
27303 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
27304 Radeon dynamic power management method (DPM). Alternatives are battery,
27307 Defaults to @samp{"performance"}.
27311 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
27312 Same as @code{radeon-dpm-state-ac} but on BAT mode.
27314 Defaults to @samp{"battery"}.
27318 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
27319 Radeon DPM performance level. Alternatives are auto, low, high.
27321 Defaults to @samp{"auto"}.
27325 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
27326 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
27328 Defaults to @samp{"auto"}.
27332 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
27333 Wifi power saving mode.
27335 Defaults to @samp{#f}.
27339 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
27340 Same as @code{wifi-power-ac?} but on BAT mode.
27342 Defaults to @samp{#t}.
27346 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
27347 Disable wake on LAN.
27349 Defaults to @samp{#t}.
27353 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
27354 Timeout duration in seconds before activating audio power saving on
27355 Intel HDA and AC97 devices. A value of 0 disables power saving.
27357 Defaults to @samp{0}.
27361 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
27362 Same as @code{sound-powersave-ac} but on BAT mode.
27364 Defaults to @samp{1}.
27368 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
27369 Disable controller in powersaving mode on Intel HDA devices.
27371 Defaults to @samp{#t}.
27375 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
27376 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
27377 powered on again by releasing (and reinserting) the eject lever or by
27378 pressing the disc eject button on newer models.
27380 Defaults to @samp{#f}.
27384 @deftypevr {@code{tlp-configuration} parameter} string bay-device
27385 Name of the optical drive device to power off.
27387 Defaults to @samp{"sr0"}.
27391 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
27392 Runtime Power Management for PCI(e) bus devices. Alternatives are on
27395 Defaults to @samp{"on"}.
27399 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
27400 Same as @code{runtime-pm-ac} but on BAT mode.
27402 Defaults to @samp{"auto"}.
27406 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
27407 Runtime Power Management for all PCI(e) bus devices, except blacklisted
27410 Defaults to @samp{#t}.
27414 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
27415 Exclude specified PCI(e) device addresses from Runtime Power Management.
27417 Defaults to @samp{disabled}.
27421 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
27422 Exclude PCI(e) devices assigned to the specified drivers from Runtime
27427 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
27428 Enable USB autosuspend feature.
27430 Defaults to @samp{#t}.
27434 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
27435 Exclude specified devices from USB autosuspend.
27437 Defaults to @samp{disabled}.
27441 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
27442 Exclude WWAN devices from USB autosuspend.
27444 Defaults to @samp{#t}.
27448 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
27449 Include specified devices into USB autosuspend, even if they are already
27450 excluded by the driver or via @code{usb-blacklist-wwan?}.
27452 Defaults to @samp{disabled}.
27456 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
27457 Enable USB autosuspend before shutdown.
27459 Defaults to @samp{disabled}.
27463 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
27464 Restore radio device state (bluetooth, wifi, wwan) from previous
27465 shutdown on system startup.
27467 Defaults to @samp{#f}.
27472 @cindex CPU frequency scaling with thermald
27473 @subsubheading Thermald daemon
27475 The @code{(gnu services pm)} module provides an interface to
27476 thermald, a CPU frequency scaling service which helps prevent overheating.
27478 @defvr {Scheme Variable} thermald-service-type
27479 This is the service type for
27480 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
27481 Thermal Daemon, which is responsible for controlling the thermal state
27482 of processors and preventing overheating.
27485 @deftp {Data Type} thermald-configuration
27486 Data type representing the configuration of @code{thermald-service-type}.
27489 @item @code{ignore-cpuid-check?} (default: @code{#f})
27490 Ignore cpuid check for supported CPU models.
27492 @item @code{thermald} (default: @var{thermald})
27493 Package object of thermald.
27498 @node Audio Services
27499 @subsection Audio Services
27501 The @code{(gnu services audio)} module provides a service to start MPD
27502 (the Music Player Daemon).
27505 @subsubheading Music Player Daemon
27507 The Music Player Daemon (MPD) is a service that can play music while
27508 being controlled from the local machine or over the network by a variety
27511 The following example shows how one might run @code{mpd} as user
27512 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
27515 (service mpd-service-type
27521 @defvr {Scheme Variable} mpd-service-type
27522 The service type for @command{mpd}
27525 @deftp {Data Type} mpd-configuration
27526 Data type representing the configuration of @command{mpd}.
27529 @item @code{user} (default: @code{"mpd"})
27530 The user to run mpd as.
27532 @item @code{music-dir} (default: @code{"~/Music"})
27533 The directory to scan for music files.
27535 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
27536 The directory to store playlists.
27538 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
27539 The location of the music database.
27541 @item @code{state-file} (default: @code{"~/.mpd/state"})
27542 The location of the file that stores current MPD's state.
27544 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
27545 The location of the sticker database.
27547 @item @code{port} (default: @code{"6600"})
27548 The port to run mpd on.
27550 @item @code{address} (default: @code{"any"})
27551 The address that mpd will bind to. To use a Unix domain socket,
27552 an absolute path can be specified here.
27554 @item @code{outputs} (default: @code{"(list (mpd-output))"})
27555 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
27560 @deftp {Data Type} mpd-output
27561 Data type representing an @command{mpd} audio output.
27564 @item @code{name} (default: @code{"MPD"})
27565 The name of the audio output.
27567 @item @code{type} (default: @code{"pulse"})
27568 The type of audio output.
27570 @item @code{enabled?} (default: @code{#t})
27571 Specifies whether this audio output is enabled when MPD is started. By
27572 default, all audio outputs are enabled. This is just the default
27573 setting when there is no state file; with a state file, the previous
27576 @item @code{tags?} (default: @code{#t})
27577 If set to @code{#f}, then MPD will not send tags to this output. This
27578 is only useful for output plugins that can receive tags, for example the
27579 @code{httpd} output plugin.
27581 @item @code{always-on?} (default: @code{#f})
27582 If set to @code{#t}, then MPD attempts to keep this audio output always
27583 open. This may be useful for streaming servers, when you don’t want to
27584 disconnect all listeners even when playback is accidentally stopped.
27586 @item @code{mixer-type}
27587 This field accepts a symbol that specifies which mixer should be used
27588 for this audio output: the @code{hardware} mixer, the @code{software}
27589 mixer, the @code{null} mixer (allows setting the volume, but with no
27590 effect; this can be used as a trick to implement an external mixer
27591 External Mixer) or no mixer (@code{none}).
27593 @item @code{extra-options} (default: @code{'()})
27594 An association list of option symbols to string values to be appended to
27595 the audio output configuration.
27600 The following example shows a configuration of @code{mpd} that provides
27601 an HTTP audio streaming output.
27604 (service mpd-service-type
27612 `((encoder . "vorbis")
27613 (port . "8080"))))))))
27617 @node Virtualization Services
27618 @subsection Virtualization Services
27620 The @code{(gnu services virtualization)} module provides services for
27621 the libvirt and virtlog daemons, as well as other virtualization-related
27624 @subsubheading Libvirt daemon
27626 @code{libvirtd} is the server side daemon component of the libvirt
27627 virtualization management system. This daemon runs on host servers
27628 and performs required management tasks for virtualized guests.
27630 @deffn {Scheme Variable} libvirt-service-type
27631 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
27632 Its value must be a @code{libvirt-configuration}.
27635 (service libvirt-service-type
27636 (libvirt-configuration
27637 (unix-sock-group "libvirt")
27638 (tls-port "16555")))
27642 @c Auto-generated with (generate-libvirt-documentation)
27643 Available @code{libvirt-configuration} fields are:
27645 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
27650 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
27651 Flag listening for secure TLS connections on the public TCP/IP port.
27652 You must set @code{listen} for this to have any effect.
27654 It is necessary to setup a CA and issue server certificates before using
27657 Defaults to @samp{#t}.
27661 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
27662 Listen for unencrypted TCP connections on the public TCP/IP port. You must
27663 set @code{listen} for this to have any effect.
27665 Using the TCP socket requires SASL authentication by default. Only SASL
27666 mechanisms which support data encryption are allowed. This is
27667 DIGEST_MD5 and GSSAPI (Kerberos5).
27669 Defaults to @samp{#f}.
27673 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
27674 Port for accepting secure TLS connections. This can be a port number,
27677 Defaults to @samp{"16514"}.
27681 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
27682 Port for accepting insecure TCP connections. This can be a port number,
27685 Defaults to @samp{"16509"}.
27689 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
27690 IP address or hostname used for client connections.
27692 Defaults to @samp{"0.0.0.0"}.
27696 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
27697 Flag toggling mDNS advertisement of the libvirt service.
27699 Alternatively can disable for all services on a host by stopping the
27702 Defaults to @samp{#f}.
27706 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
27707 Default mDNS advertisement name. This must be unique on the immediate
27710 Defaults to @samp{"Virtualization Host <hostname>"}.
27714 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
27715 UNIX domain socket group ownership. This can be used to allow a
27716 'trusted' set of users access to management capabilities without
27719 Defaults to @samp{"root"}.
27723 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
27724 UNIX socket permissions for the R/O socket. This is used for monitoring
27727 Defaults to @samp{"0777"}.
27731 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
27732 UNIX socket permissions for the R/W socket. Default allows only root.
27733 If PolicyKit is enabled on the socket, the default will change to allow
27734 everyone (eg, 0777)
27736 Defaults to @samp{"0770"}.
27740 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
27741 UNIX socket permissions for the admin socket. Default allows only owner
27742 (root), do not change it unless you are sure to whom you are exposing
27745 Defaults to @samp{"0777"}.
27749 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
27750 The directory in which sockets will be found/created.
27752 Defaults to @samp{"/var/run/libvirt"}.
27756 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
27757 Authentication scheme for UNIX read-only sockets. By default socket
27758 permissions allow anyone to connect
27760 Defaults to @samp{"polkit"}.
27764 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
27765 Authentication scheme for UNIX read-write sockets. By default socket
27766 permissions only allow root. If PolicyKit support was compiled into
27767 libvirt, the default will be to use 'polkit' auth.
27769 Defaults to @samp{"polkit"}.
27773 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
27774 Authentication scheme for TCP sockets. If you don't enable SASL, then
27775 all TCP traffic is cleartext. Don't do this outside of a dev/test
27778 Defaults to @samp{"sasl"}.
27782 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
27783 Authentication scheme for TLS sockets. TLS sockets already have
27784 encryption provided by the TLS layer, and limited authentication is done
27787 It is possible to make use of any SASL authentication mechanism as well,
27788 by using 'sasl' for this option
27790 Defaults to @samp{"none"}.
27794 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
27795 API access control scheme.
27797 By default an authenticated user is allowed access to all APIs. Access
27798 drivers can place restrictions on this.
27800 Defaults to @samp{()}.
27804 @deftypevr {@code{libvirt-configuration} parameter} string key-file
27805 Server key file path. If set to an empty string, then no private key is
27808 Defaults to @samp{""}.
27812 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
27813 Server key file path. If set to an empty string, then no certificate is
27816 Defaults to @samp{""}.
27820 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
27821 Server key file path. If set to an empty string, then no CA certificate
27824 Defaults to @samp{""}.
27828 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
27829 Certificate revocation list path. If set to an empty string, then no
27832 Defaults to @samp{""}.
27836 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
27837 Disable verification of our own server certificates.
27839 When libvirtd starts it performs some sanity checks against its own
27842 Defaults to @samp{#f}.
27846 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
27847 Disable verification of client certificates.
27849 Client certificate verification is the primary authentication mechanism.
27850 Any client which does not present a certificate signed by the CA will be
27853 Defaults to @samp{#f}.
27857 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
27858 Whitelist of allowed x509 Distinguished Name.
27860 Defaults to @samp{()}.
27864 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
27865 Whitelist of allowed SASL usernames. The format for username depends on
27866 the SASL authentication mechanism.
27868 Defaults to @samp{()}.
27872 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
27873 Override the compile time default TLS priority string. The default is
27874 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
27875 is desired for libvirt to deviate from the global default settings.
27877 Defaults to @samp{"NORMAL"}.
27881 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
27882 Maximum number of concurrent client connections to allow over all
27885 Defaults to @samp{5000}.
27889 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
27890 Maximum length of queue of connections waiting to be accepted by the
27891 daemon. Note, that some protocols supporting retransmission may obey
27892 this so that a later reattempt at connection succeeds.
27894 Defaults to @samp{1000}.
27898 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
27899 Maximum length of queue of accepted but not yet authenticated clients.
27900 Set this to zero to turn this feature off
27902 Defaults to @samp{20}.
27906 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
27907 Number of workers to start up initially.
27909 Defaults to @samp{5}.
27913 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
27914 Maximum number of worker threads.
27916 If the number of active clients exceeds @code{min-workers}, then more
27917 threads are spawned, up to max_workers limit. Typically you'd want
27918 max_workers to equal maximum number of clients allowed.
27920 Defaults to @samp{20}.
27924 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
27925 Number of priority workers. If all workers from above pool are stuck,
27926 some calls marked as high priority (notably domainDestroy) can be
27927 executed in this pool.
27929 Defaults to @samp{5}.
27933 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
27934 Total global limit on concurrent RPC calls.
27936 Defaults to @samp{20}.
27940 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
27941 Limit on concurrent requests from a single client connection. To avoid
27942 one client monopolizing the server this should be a small fraction of
27943 the global max_requests and max_workers parameter.
27945 Defaults to @samp{5}.
27949 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
27950 Same as @code{min-workers} but for the admin interface.
27952 Defaults to @samp{1}.
27956 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
27957 Same as @code{max-workers} but for the admin interface.
27959 Defaults to @samp{5}.
27963 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
27964 Same as @code{max-clients} but for the admin interface.
27966 Defaults to @samp{5}.
27970 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
27971 Same as @code{max-queued-clients} but for the admin interface.
27973 Defaults to @samp{5}.
27977 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
27978 Same as @code{max-client-requests} but for the admin interface.
27980 Defaults to @samp{5}.
27984 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
27985 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
27987 Defaults to @samp{3}.
27991 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
27994 A filter allows to select a different logging level for a given category
27995 of logs. The format for a filter is one of:
28006 where @code{name} is a string which is matched against the category
28007 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
28008 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
28009 name in the filter can be a substring of the full category name, in
28010 order to match multiple similar categories), the optional @samp{"+"}
28011 prefix tells libvirt to log stack trace for each message matching name,
28012 and @code{x} is the minimal level where matching messages should be
28030 Multiple filters can be defined in a single filters statement, they just
28031 need to be separated by spaces.
28033 Defaults to @samp{"3:remote 4:event"}.
28037 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
28040 An output is one of the places to save logging information. The format
28041 for an output can be:
28045 output goes to stderr
28047 @item x:syslog:name
28048 use syslog for the output and use the given name as the ident
28050 @item x:file:file_path
28051 output to a file, with the given filepath
28054 output to journald logging system
28058 In all case the x prefix is the minimal level, acting as a filter
28075 Multiple outputs can be defined, they just need to be separated by
28078 Defaults to @samp{"3:stderr"}.
28082 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
28083 Allows usage of the auditing subsystem to be altered
28087 0: disable all auditing
28090 1: enable auditing, only if enabled on host
28093 2: enable auditing, and exit if disabled on host.
28097 Defaults to @samp{1}.
28101 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
28102 Send audit messages via libvirt logging infrastructure.
28104 Defaults to @samp{#f}.
28108 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
28109 Host UUID@. UUID must not have all digits be the same.
28111 Defaults to @samp{""}.
28115 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
28116 Source to read host UUID.
28120 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
28123 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
28127 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
28130 Defaults to @samp{"smbios"}.
28134 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
28135 A keepalive message is sent to a client after @code{keepalive_interval}
28136 seconds of inactivity to check if the client is still responding. If
28137 set to -1, libvirtd will never send keepalive requests; however clients
28138 can still send them and the daemon will send responses.
28140 Defaults to @samp{5}.
28144 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
28145 Maximum number of keepalive messages that are allowed to be sent to the
28146 client without getting any response before the connection is considered
28149 In other words, the connection is automatically closed approximately
28150 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
28151 the last message received from the client. When @code{keepalive-count}
28152 is set to 0, connections will be automatically closed after
28153 @code{keepalive-interval} seconds of inactivity without sending any
28154 keepalive messages.
28156 Defaults to @samp{5}.
28160 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
28161 Same as above but for admin interface.
28163 Defaults to @samp{5}.
28167 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
28168 Same as above but for admin interface.
28170 Defaults to @samp{5}.
28174 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
28175 Timeout for Open vSwitch calls.
28177 The @code{ovs-vsctl} utility is used for the configuration and its
28178 timeout option is set by default to 5 seconds to avoid potential
28179 infinite waits blocking libvirt.
28181 Defaults to @samp{5}.
28185 @c %end of autogenerated docs
28187 @subsubheading Virtlog daemon
28188 The virtlogd service is a server side daemon component of libvirt that is
28189 used to manage logs from virtual machine consoles.
28191 This daemon is not used directly by libvirt client applications, rather it
28192 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
28193 standalone daemon, the main @code{libvirtd} daemon can be restarted without
28194 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
28195 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
28197 @deffn {Scheme Variable} virtlog-service-type
28198 This is the type of the virtlog daemon.
28199 Its value must be a @code{virtlog-configuration}.
28202 (service virtlog-service-type
28203 (virtlog-configuration
28204 (max-clients 1000)))
28208 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
28209 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
28211 Defaults to @samp{3}.
28215 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
28218 A filter allows to select a different logging level for a given category
28219 of logs The format for a filter is one of:
28230 where @code{name} is a string which is matched against the category
28231 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
28232 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
28233 be a substring of the full category name, in order to match multiple
28234 similar categories), the optional "+" prefix tells libvirt to log stack
28235 trace for each message matching name, and @code{x} is the minimal level
28236 where matching messages should be logged:
28253 Multiple filters can be defined in a single filters statement, they just
28254 need to be separated by spaces.
28256 Defaults to @samp{"3:remote 4:event"}.
28260 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
28263 An output is one of the places to save logging information The format
28264 for an output can be:
28268 output goes to stderr
28270 @item x:syslog:name
28271 use syslog for the output and use the given name as the ident
28273 @item x:file:file_path
28274 output to a file, with the given filepath
28277 output to journald logging system
28281 In all case the x prefix is the minimal level, acting as a filter
28298 Multiple outputs can be defined, they just need to be separated by
28301 Defaults to @samp{"3:stderr"}.
28305 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
28306 Maximum number of concurrent client connections to allow over all
28309 Defaults to @samp{1024}.
28313 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
28314 Maximum file size before rolling over.
28316 Defaults to @samp{2MB}
28320 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
28321 Maximum number of backup files to keep.
28323 Defaults to @samp{3}
28327 @anchor{transparent-emulation-qemu}
28328 @subsubheading Transparent Emulation with QEMU
28331 @cindex @code{binfmt_misc}
28332 @code{qemu-binfmt-service-type} provides support for transparent
28333 emulation of program binaries built for different architectures---e.g.,
28334 it allows you to transparently execute an ARMv7 program on an x86_64
28335 machine. It achieves this by combining the @uref{https://www.qemu.org,
28336 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
28337 This feature only allows you to emulate GNU/Linux on a different
28338 architecture, but see below for GNU/Hurd support.
28340 @defvr {Scheme Variable} qemu-binfmt-service-type
28341 This is the type of the QEMU/binfmt service for transparent emulation.
28342 Its value must be a @code{qemu-binfmt-configuration} object, which
28343 specifies the QEMU package to use as well as the architecture we want to
28347 (service qemu-binfmt-service-type
28348 (qemu-binfmt-configuration
28349 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
28352 In this example, we enable transparent emulation for the ARM and aarch64
28353 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
28354 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
28355 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
28358 @deftp {Data Type} qemu-binfmt-configuration
28359 This is the configuration for the @code{qemu-binfmt} service.
28362 @item @code{platforms} (default: @code{'()})
28363 The list of emulated QEMU platforms. Each item must be a @dfn{platform
28364 object} as returned by @code{lookup-qemu-platforms} (see below).
28366 @item @code{guix-support?} (default: @code{#t})
28367 When it is true, QEMU and all its dependencies are added to the build
28368 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
28369 @option{--chroot-directory} option}). This allows the @code{binfmt_misc}
28370 handlers to be used within the build environment, which in turn means
28371 that you can transparently build programs for another architecture.
28373 For example, let's suppose you're on an x86_64 machine and you have this
28377 (service qemu-binfmt-service-type
28378 (qemu-binfmt-configuration
28379 (platforms (lookup-qemu-platforms "arm"))
28380 (guix-support? #t)))
28386 guix build -s armhf-linux inkscape
28390 and it will build Inkscape for ARMv7 @emph{as if it were a native
28391 build}, transparently using QEMU to emulate the ARMv7 CPU@. Pretty handy
28392 if you'd like to test a package build for an architecture you don't have
28395 When @code{guix-support?} is set to @code{#f}, programs for other
28396 architectures can still be executed transparently, but invoking commands
28397 like @command{guix build -s armhf-linux @dots{}} will fail.
28399 @item @code{qemu} (default: @code{qemu})
28400 The QEMU package to use.
28404 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
28405 Return the list of QEMU platform objects corresponding to
28406 @var{platforms}@dots{}. @var{platforms} must be a list of strings
28407 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
28408 @code{"mips64el"}, and so on.
28411 @deffn {Scheme Procedure} qemu-platform? @var{obj}
28412 Return true if @var{obj} is a platform object.
28415 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
28416 Return the name of @var{platform}---a string such as @code{"arm"}.
28420 @subsubheading The Hurd in a Virtual Machine
28422 @cindex @code{hurd}
28426 Service @code{hurd-vm} provides support for running GNU/Hurd in a
28427 virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
28428 to be used on GNU/Linux and the given GNU/Hurd operating system
28429 configuration is cross-compiled. The virtual machine is a Shepherd
28430 service that can be referred to by the names @code{hurd-vm} and
28431 @code{childhurd} and be controlled with commands such as:
28435 herd stop childhurd
28438 When the service is running, you can view its console by connecting to
28439 it with a VNC client, for example with:
28442 guix environment --ad-hoc tigervnc-client -- \
28443 vncviewer localhost:5900
28446 The default configuration (see @code{hurd-vm-configuration} below)
28447 spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
28448 (the virtual machine emulator) redirects to port 10222 on the host.
28449 Thus, you can connect over SSH to the childhurd with:
28452 ssh root@@localhost -p 10022
28455 The childhurd is volatile and stateless: it starts with a fresh root
28456 file system every time you restart it. By default though, all the files
28457 under @file{/etc/childhurd} on the host are copied as is to the root
28458 file system of the childhurd when it boots. This allows you to
28459 initialize ``secrets'' inside the VM: SSH host keys, authorized
28460 substitute keys, and so on---see the explanation of @code{secret-root}
28463 @defvr {Scheme Variable} hurd-vm-service-type
28464 This is the type of the Hurd in a Virtual Machine service. Its value
28465 must be a @code{hurd-vm-configuration} object, which specifies the
28466 operating system (@pxref{operating-system Reference}) and the disk size
28467 for the Hurd Virtual Machine, the QEMU package to use as well as the
28468 options for running it.
28473 (service hurd-vm-service-type
28474 (hurd-vm-configuration
28475 (disk-size (* 5000 (expt 2 20))) ;5G
28476 (memory-size 1024))) ;1024MiB
28479 would create a disk image big enough to build GNU@tie{}Hello, with some
28483 @deftp {Data Type} hurd-vm-configuration
28484 The data type representing the configuration for
28485 @code{hurd-vm-service-type}.
28488 @item @code{os} (default: @var{%hurd-vm-operating-system})
28489 The operating system to instantiate. This default is bare-bones with a
28490 permissive OpenSSH secure shell daemon listening on port 2222
28491 (@pxref{Networking Services, @code{openssh-service-type}}).
28493 @item @code{qemu} (default: @code{qemu-minimal})
28494 The QEMU package to use.
28496 @item @code{image} (default: @var{hurd-vm-disk-image})
28497 The procedure used to build the disk-image built from this
28500 @item @code{disk-size} (default: @code{'guess})
28501 The size of the disk image.
28503 @item @code{memory-size} (default: @code{512})
28504 The memory size of the Virtual Machine in mebibytes.
28506 @item @code{options} (default: @code{'("--snapshot")})
28507 The extra options for running QEMU.
28509 @item @code{id} (default: @code{#f})
28510 If set, a non-zero positive integer used to parameterize Childhurd
28511 instances. It is appended to the service's name,
28512 e.g. @code{childhurd1}.
28514 @item @code{net-options} (default: @var{hurd-vm-net-options})
28515 The procedure used to produce the list of QEMU networking options.
28517 By default, it produces
28520 '("--device" "rtl8139,netdev=net0"
28521 "--netdev" "user,id=net0\
28522 ,hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004\
28523 ,hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222\
28524 ,hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900")
28527 with forwarded ports:
28530 @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
28531 @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
28532 @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
28535 @item @code{secret-root} (default: @file{/etc/childhurd})
28536 The root directory with out-of-band secrets to be installed into the
28537 childhurd once it runs. Childhurds are volatile which means that on
28538 every startup, secrets such as the SSH host keys and Guix signing key
28541 If the @file{/etc/childhurd} directory does not exist, the
28542 @code{secret-service} running in the Childhurd will be sent an empty
28545 By default, the service automatically populates @file{/etc/childhurd}
28546 with the following non-volatile secrets, unless they already exist:
28549 /etc/childhurd/etc/guix/acl
28550 /etc/childhurd/etc/guix/signing-key.pub
28551 /etc/childhurd/etc/guix/signing-key.sec
28552 /etc/childhurd/etc/ssh/ssh_host_ed25519_key
28553 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
28554 /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
28555 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
28558 These files are automatically sent to the guest Hurd VM when it boots,
28559 including permissions.
28561 @cindex childhurd, offloading
28562 @cindex Hurd, offloading
28563 Having these files in place means that only a couple of things are
28564 missing to allow the host to offload @code{i586-gnu} builds to the
28569 Authorizing the childhurd's key on the host so that the host accepts
28570 build results coming from the childhurd, which can be done like so:
28573 guix archive --authorize < \
28574 /etc/childhurd/etc/guix/signing-key.pub
28578 Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
28582 We're working towards making that happen automatically---get in touch
28583 with us at @email{guix-devel@@gnu.org} to discuss it!
28587 Note that by default the VM image is volatile, i.e., once stopped the
28588 contents are lost. If you want a stateful image instead, override the
28589 configuration's @code{image} and @code{options} without
28590 the @code{--snapshot} flag using something along these lines:
28593 (service hurd-vm-service-type
28594 (hurd-vm-configuration
28595 (image (const "/out/of/store/writable/hurd.img"))
28599 @subsubheading Ganeti
28604 This service is considered experimental. Configuration options may be changed
28605 in a backwards-incompatible manner, and not all features have been thorougly
28606 tested. Users of this service are encouraged to share their experience at
28607 @email{guix-devel@@gnu.org}.
28610 Ganeti is a virtual machine management system. It is designed to keep virtual
28611 machines running on a cluster of servers even in the event of hardware failures,
28612 and to make maintenance and recovery tasks easy. It consists of multiple
28613 services which are described later in this section. In addition to the Ganeti
28614 service, you will need the OpenSSH service (@pxref{Networking Services,
28615 @code{openssh-service-type}}), and update the @file{/etc/hosts} file
28616 (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
28617 and address (or use a DNS server).
28619 All nodes participating in a Ganeti cluster should have the same Ganeti and
28620 @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
28621 cluster node that supports multiple storage backends, and installs the
28622 @code{debootstrap} and @code{guix} @dfn{OS providers}:
28625 (use-package-modules virtualization)
28626 (use-service-modules base ganeti networking ssh)
28629 (host-name "node1")
28630 (hosts-file (plain-file "hosts" (format #f "
28631 127.0.0.1 localhost
28634 192.168.1.200 ganeti.example.com
28635 192.168.1.201 node1.example.com node1
28636 192.168.1.202 node2.example.com node2
28639 ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
28640 ;; in order to use the "plain", "drbd" and "rbd" storage backends.
28641 (packages (append (map specification->package
28642 '("qemu" "lvm2" "drbd-utils" "ceph"
28643 ;; Add the debootstrap and guix OS providers.
28644 "ganeti-instance-guix" "ganeti-instance-debootstrap"))
28647 (append (list (static-networking-service "eth0" "192.168.1.201"
28648 #:netmask "255.255.255.0"
28649 #:gateway "192.168.1.254"
28650 #:name-servers '("192.168.1.252"
28653 ;; Ganeti uses SSH to communicate between nodes.
28654 (service openssh-service-type
28655 (openssh-configuration
28656 (permit-root-login 'without-password)))
28658 (service ganeti-service-type
28659 (ganeti-configuration
28660 ;; This list specifies allowed file system paths
28661 ;; for storing virtual machine images.
28662 (file-storage-paths '("/srv/ganeti/file-storage"))
28663 ;; This variable configures a single "variant" for
28664 ;; both Debootstrap and Guix that works with KVM.
28665 (os %default-ganeti-os))))
28669 Users are advised to read the
28670 @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
28671 administrators guide} to learn about the various cluster options and
28672 day-to-day operations. There is also a
28673 @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
28674 describing how to configure and initialize a small cluster.
28676 @defvr {Scheme Variable} ganeti-service-type
28677 This is a service type that includes all the various services that Ganeti
28680 Its value is a @code{ganeti-configuration} object that defines the package
28681 to use for CLI operations, as well as configuration for the various daemons.
28682 Allowed file storage paths and available guest operating systems are also
28683 configured through this data type.
28686 @deftp {Data Type} ganeti-configuration
28687 The @code{ganeti} service takes the following configuration options:
28690 @item @code{ganeti} (default: @code{ganeti})
28691 The @code{ganeti} package to use. It will be installed to the system profile
28692 and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
28693 that the value specified here does not affect the other services as each refer
28694 to a specific @code{ganeti} package (see below).
28696 @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
28697 @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
28698 @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
28699 @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
28700 @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
28701 @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
28702 @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
28703 @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
28704 @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
28705 @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
28707 These options control the various daemons and cron jobs that are distributed
28708 with Ganeti. The possible values for these are described in detail below.
28709 To override a setting, you must use the configuration type for that service:
28712 (service ganeti-service-type
28713 (ganeti-configuration
28714 (rapi-configuration
28715 (ganeti-rapi-configuration
28716 (interface "eth1"))))
28717 (watcher-configuration
28718 (ganeti-watcher-configuration
28719 (rapi-ip "10.0.0.1"))))
28722 @item @code{file-storage-paths} (default: @code{'()})
28723 List of allowed directories for file storage backend.
28725 @item @code{os} (default: @code{%default-ganeti-os})
28726 List of @code{<ganeti-os>} records.
28729 In essence @code{ganeti-service-type} is shorthand for declaring each service
28733 (service ganeti-noded-service-type)
28734 (service ganeti-confd-service-type)
28735 (service ganeti-wconfd-service-type)
28736 (service ganeti-luxid-service-type)
28737 (service ganeti-kvmd-service-type)
28738 (service ganeti-mond-service-type)
28739 (service ganeti-metad-service-type)
28740 (service ganeti-watcher-service-type)
28741 (service ganeti-cleaner-service-type)
28744 Plus a service extension for @code{etc-service-type} that configures the file
28745 storage backend and OS variants.
28749 @deftp {Data Type} ganeti-os
28750 This data type is suitable for passing to the @code{os} parameter of
28751 @code{ganeti-configuration}. It takes the following parameters:
28755 The name for this OS provider. It is only used to specify where the
28756 configuration ends up. Setting it to ``debootstrap'' will create
28757 @file{/etc/ganeti/instance-debootstrap}.
28759 @item @code{extension}
28760 The file extension for variants of this OS type. For example
28761 @file{.conf} or @file{.scm}.
28763 @item @code{variants} (default: @code{'()})
28764 List of @code{ganeti-os-variant} objects for this OS.
28769 @deftp {Data Type} ganeti-os-variant
28770 This is the data type for a Ganeti OS variant. It takes the following
28775 The name of this variant.
28777 @item @code{configuration}
28778 A configuration file for this variant.
28782 @defvr {Scheme Variable} %default-debootstrap-hooks
28783 This variable contains hooks to configure networking and the GRUB bootloader.
28786 @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
28787 This variable contains a list of packages suitable for a fully-virtualized guest.
28790 @deftp {Data Type} debootstrap-configuration
28792 This data type creates configuration files suitable for the debootstrap OS provider.
28795 @item @code{hooks} (default: @code{%default-debootstrap-hooks})
28796 When not @code{#f}, this must be a G-expression that specifies a directory with
28797 scripts that will run when the OS is installed. It can also be a list of
28798 @code{(name . file-like)} pairs. For example:
28801 `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
28804 That will create a directory with one executable named @code{99-hello-world}
28805 and run it every time this variant is installed. If set to @code{#f}, hooks
28806 in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
28807 @item @code{proxy} (default: @code{#f})
28808 Optional HTTP proxy to use.
28809 @item @code{mirror} (default: @code{#f})
28810 The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
28811 The default varies depending on the distribution.
28812 @item @code{arch} (default: @code{#f})
28813 The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
28814 on an AArch64 host. Default is to use the current system architecture.
28815 @item @code{suite} (default: @code{"stable"})
28816 When set, this must be a Debian distribution ``suite'' such as @code{buster}
28817 or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
28818 @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
28819 List of extra packages that will get installed by dpkg in addition
28820 to the minimal system.
28821 @item @code{components} (default: @code{#f})
28822 When set, must be a list of Debian repository ``components''. For example
28823 @code{'("main" "contrib")}.
28824 @item @code{generate-cache?} (default: @code{#t})
28825 Whether to automatically cache the generated debootstrap archive.
28826 @item @code{clean-cache} (default: @code{14})
28827 Discard the cache after this amount of days. Use @code{#f} to never
28829 @item @code{partition-style} (default: @code{'msdos})
28830 The type of partition to create. When set, it must be one of
28831 @code{'msdos}, @code{'none} or a string.
28832 @item @code{partition-alignment} (default: @code{2048})
28833 Alignment of the partition in sectors.
28837 @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
28838 This is a helper procedure that creates a @code{ganeti-os-variant} record. It
28839 takes two parameters: a name and a @code{debootstrap-configuration} object.
28842 @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
28843 This is a helper procedure that creates a @code{ganeti-os} record. It takes
28844 a list of variants created with @code{debootstrap-variant}.
28847 @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
28848 This is a helper procedure that creates a @code{ganeti-os-variant} record for
28849 use with the Guix OS provider. It takes a name and a G-expression that returns
28850 a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
28851 Guix System configuration.
28854 @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
28855 This is a helper procedure that creates a @code{ganeti-os} record. It
28856 takes a list of variants produced by @code{guix-variant}.
28859 @defvr {Scheme Variable} %default-debootstrap-variants
28860 This is a convenience variable to make the debootstrap provider work
28861 ``out of the box'' without users having to declare variants manually. It
28862 contains a single debootstrap variant with the default configuration:
28865 (list (debootstrap-variant
28867 (debootstrap-configuration)))
28871 @defvr {Scheme Variable} %default-guix-variants
28872 This is a convenience variable to make the Guix OS provider work without
28873 additional configuration. It creates a virtual machine that has an SSH
28874 server, a serial console, and authorizes the Ganeti hosts SSH keys.
28877 (list (guix-variant
28879 (file-append ganeti-instance-guix
28880 "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
28884 Users can implement support for OS providers unbeknownst to Guix by extending
28885 the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
28891 (extension ".conf")
28893 (list (ganeti-os-variant
28895 (configuration (plain-file "bar" "this is fine"))))))
28898 That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
28899 to a file in the store with contents @code{this is fine}. It also creates
28900 @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
28902 Obviously this may not work for all OS providers out there. If you find the
28903 interface limiting, please reach out to @email{guix-devel@@gnu.org}.
28905 The rest of this section documents the various services that are included by
28906 @code{ganeti-service-type}.
28908 @defvr {Scheme Variable} ganeti-noded-service-type
28909 @command{ganeti-noded} is the daemon responsible for node-specific functions
28910 within the Ganeti system. The value of this service must be a
28911 @code{ganeti-noded-configuration} object.
28914 @deftp {Data Type} ganeti-noded-configuration
28915 This is the configuration for the @code{ganeti-noded} service.
28918 @item @code{ganeti} (default: @code{ganeti})
28919 The @code{ganeti} package to use for this service.
28921 @item @code{port} (default: @code{1811})
28922 The TCP port on which the node daemon listens for network requests.
28924 @item @code{address} (default: @code{"0.0.0.0"})
28925 The network address that the daemon will bind to. The default address means
28926 bind to all available addresses.
28928 @item @code{interface} (default: @code{#f})
28929 When this is set, it must be a specific network interface (e.g.@: @code{eth0})
28930 that the daemon will bind to.
28932 @item @code{max-clients} (default: @code{20})
28933 This sets a limit on the maximum number of simultaneous client connections
28934 that the daemon will handle. Connections above this count are accepted, but
28935 no responses will be sent until enough connections have closed.
28937 @item @code{ssl?} (default: @code{#t})
28938 Whether to use SSL/TLS to encrypt network communications. The certificate
28939 is automatically provisioned by the cluster and can be rotated with
28940 @command{gnt-cluster renew-crypto}.
28942 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
28943 This can be used to provide a specific encryption key for TLS communications.
28945 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
28946 This can be used to provide a specific certificate for TLS communications.
28948 @item @code{debug?} (default: @code{#f})
28949 When true, the daemon performs additional logging for debugging purposes.
28950 Note that this will leak encryption details to the log files, use with caution.
28955 @defvr {Scheme Variable} ganeti-confd-service-type
28956 @command{ganeti-confd} answers queries related to the configuration of a
28957 Ganeti cluster. The purpose of this daemon is to have a highly available
28958 and fast way to query cluster configuration values. It is automatically
28959 active on all @dfn{master candidates}. The value of this service must be a
28960 @code{ganeti-confd-configuration} object.
28964 @deftp {Data Type} ganeti-confd-configuration
28965 This is the configuration for the @code{ganeti-confd} service.
28968 @item @code{ganeti} (default: @code{ganeti})
28969 The @code{ganeti} package to use for this service.
28971 @item @code{port} (default: @code{1814})
28972 The UDP port on which to listen for network requests.
28974 @item @code{address} (default: @code{"0.0.0.0"})
28975 Network address that the daemon will bind to.
28977 @item @code{debug?} (default: @code{#f})
28978 When true, the daemon performs additional logging for debugging purposes.
28983 @defvr {Scheme Variable} ganeti-wconfd-service-type
28984 @command{ganeti-wconfd} is the daemon that has authoritative knowledge
28985 about the cluster configuration and is the only entity that can accept
28986 changes to it. All jobs that need to modify the configuration will do so
28987 by sending appropriate requests to this daemon. It only runs on the
28988 @dfn{master node} and will automatically disable itself on other nodes.
28990 The value of this service must be a
28991 @code{ganeti-wconfd-configuration} object.
28994 @deftp {Data Type} ganeti-wconfd-configuration
28995 This is the configuration for the @code{ganeti-wconfd} service.
28998 @item @code{ganeti} (default: @code{ganeti})
28999 The @code{ganeti} package to use for this service.
29001 @item @code{no-voting?} (default: @code{#f})
29002 The daemon will refuse to start if the majority of cluster nodes does not
29003 agree that it is running on the master node. Set to @code{#t} to start
29004 even if a quorum can not be reached (dangerous, use with caution).
29006 @item @code{debug?} (default: @code{#f})
29007 When true, the daemon performs additional logging for debugging purposes.
29012 @defvr {Scheme Variable} ganeti-luxid-service-type
29013 @command{ganeti-luxid} is a daemon used to answer queries related to the
29014 configuration and the current live state of a Ganeti cluster. Additionally,
29015 it is the authoritative daemon for the Ganeti job queue. Jobs can be
29016 submitted via this daemon and it schedules and starts them.
29018 It takes a @code{ganeti-luxid-configuration} object.
29021 @deftp {Data Type} ganeti-luxid-configuration
29022 This is the configuration for the @code{ganeti-wconfd} service.
29025 @item @code{ganeti} (default: @code{ganeti})
29026 The @code{ganeti} package to use for this service.
29028 @item @code{no-voting?} (default: @code{#f})
29029 The daemon will refuse to start if it cannot verify that the majority of
29030 cluster nodes believes that it is running on the master node. Set to
29031 @code{#t} to ignore such checks and start anyway (this can be dangerous).
29033 @item @code{debug?} (default: @code{#f})
29034 When true, the daemon performs additional logging for debugging purposes.
29039 @defvr {Scheme Variable} ganeti-rapi-service-type
29040 @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
29041 the master node and can be used to perform cluster actions programmatically
29042 via a JSON-based RPC protocol.
29044 Most query operations are allowed without authentication (unless
29045 @var{require-authentication?} is set), whereas write operations require
29046 explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
29047 the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
29048 API documentation} for more information.
29050 The value of this service must be a @code{ganeti-rapi-configuration} object.
29053 @deftp {Data Type} ganeti-rapi-configuration
29054 This is the configuration for the @code{ganeti-rapi} service.
29057 @item @code{ganeti} (default: @code{ganeti})
29058 The @code{ganeti} package to use for this service.
29060 @item @code{require-authentication?} (default: @code{#f})
29061 Whether to require authentication even for read-only operations.
29063 @item @code{port} (default: @code{5080})
29064 The TCP port on which to listen to API requests.
29066 @item @code{address} (default: @code{"0.0.0.0"})
29067 The network address that the service will bind to. By default it listens
29068 on all configured addresses.
29070 @item @code{interface} (default: @code{#f})
29071 When set, it must specify a specific network interface such as @code{eth0}
29072 that the daemon will bind to.
29074 @item @code{max-clients} (default: @code{20})
29075 The maximum number of simultaneous client requests to handle. Further
29076 connections are allowed, but no responses are sent until enough connections
29079 @item @code{ssl?} (default: @code{#t})
29080 Whether to use SSL/TLS encryption on the RAPI port.
29082 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
29083 This can be used to provide a specific encryption key for TLS communications.
29085 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
29086 This can be used to provide a specific certificate for TLS communications.
29088 @item @code{debug?} (default: @code{#f})
29089 When true, the daemon performs additional logging for debugging purposes.
29090 Note that this will leak encryption details to the log files, use with caution.
29095 @defvr {Scheme Variable} ganeti-kvmd-service-type
29096 @command{ganeti-kvmd} is responsible for determining whether a given KVM
29097 instance was shut down by an administrator or a user. Normally Ganeti will
29098 restart an instance that was not stopped through Ganeti itself. If the
29099 cluster option @code{user_shutdown} is true, this daemon monitors the
29100 @code{QMP} socket provided by QEMU and listens for shutdown events, and
29101 marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
29102 it shuts down gracefully by itself.
29104 It takes a @code{ganeti-kvmd-configuration} object.
29107 @deftp {Data Type} ganeti-kvmd-configuration
29110 @item @code{ganeti} (default: @code{ganeti})
29111 The @code{ganeti} package to use for this service.
29113 @item @code{debug?} (default: @code{#f})
29114 When true, the daemon performs additional logging for debugging purposes.
29119 @defvr {Scheme Variable} ganeti-mond-service-type
29120 @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
29121 functionality. It is responsible for running data collectors and publish the
29122 collected information through a HTTP interface.
29124 It takes a @code{ganeti-mond-configuration} object.
29127 @deftp {Data Type} ganeti-mond-configuration
29130 @item @code{ganeti} (default: @code{ganeti})
29131 The @code{ganeti} package to use for this service.
29133 @item @code{port} (default: @code{1815})
29134 The port on which the daemon will listen.
29136 @item @code{address} (default: @code{"0.0.0.0"})
29137 The network address that the daemon will bind to. By default it binds to all
29138 available interfaces.
29140 @item @code{debug?} (default: @code{#f})
29141 When true, the daemon performs additional logging for debugging purposes.
29146 @defvr {Scheme Variable} ganeti-metad-service-type
29147 @command{ganeti-metad} is an optional daemon that can be used to provide
29148 information about the cluster to instances or OS install scripts.
29150 It takes a @code{ganeti-metad-configuration} object.
29153 @deftp {Data Type} ganeti-metad-configuration
29156 @item @code{ganeti} (default: @code{ganeti})
29157 The @code{ganeti} package to use for this service.
29159 @item @code{port} (default: @code{80})
29160 The port on which the daemon will listen.
29162 @item @code{address} (default: @code{#f})
29163 If set, the daemon will bind to this address only. If left unset, the behavior
29164 depends on the cluster configuration.
29166 @item @code{debug?} (default: @code{#f})
29167 When true, the daemon performs additional logging for debugging purposes.
29172 @defvr {Scheme Variable} ganeti-watcher-service-type
29173 @command{ganeti-watcher} is a script designed to run periodically and ensure
29174 the health of a cluster. It will automatically restart instances that have
29175 stopped without Ganeti's consent, and repairs DRBD links in case a node has
29176 rebooted. It also archives old cluster jobs and restarts Ganeti daemons
29177 that are not running. If the cluster parameter @code{ensure_node_health}
29178 is set, the watcher will also shutdown instances and DRBD devices if the
29179 node it is running on is declared offline by known master candidates.
29181 It can be paused on all nodes with @command{gnt-cluster watcher pause}.
29183 The service takes a @code{ganeti-watcher-configuration} object.
29186 @deftp {Data Type} ganeti-watcher-configuration
29189 @item @code{ganeti} (default: @code{ganeti})
29190 The @code{ganeti} package to use for this service.
29192 @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
29193 How often to run the script. The default is every five minutes.
29195 @item @code{rapi-ip} (default: @code{#f})
29196 This option needs to be specified only if the RAPI daemon is configured to use
29197 a particular interface or address. By default the cluster address is used.
29199 @item @code{job-age} (default: @code{(* 6 3600)})
29200 Archive cluster jobs older than this age, specified in seconds. The default
29201 is 6 hours. This keeps @command{gnt-job list} manageable.
29203 @item @code{verify-disks?} (default: @code{#t})
29204 If this is @code{#f}, the watcher will not try to repair broken DRBD links
29205 automatically. Administrators will need to use @command{gnt-cluster verify-disks}
29208 @item @code{debug?} (default: @code{#f})
29209 When @code{#t}, the script performs additional logging for debugging purposes.
29214 @defvr {Scheme Variable} ganeti-cleaner-service-type
29215 @command{ganeti-cleaner} is a script designed to run periodically and remove
29216 old files from the cluster. This service type controls two @dfn{cron jobs}:
29217 one intended for the master node that permanently purges old cluster jobs,
29218 and one intended for every node that removes expired X509 certificates, keys,
29219 and outdated @command{ganeti-watcher} information. Like all Ganeti services,
29220 it is safe to include even on non-master nodes as it will disable itself as
29223 It takes a @code{ganeti-cleaner-configuration} object.
29226 @deftp {Data Type} ganeti-cleaner-configuration
29229 @item @code{ganeti} (default: @code{ganeti})
29230 The @code{ganeti} package to use for the @command{gnt-cleaner} command.
29232 @item @code{master-schedule} (default: @code{"45 1 * * *"})
29233 How often to run the master cleaning job. The default is once per day, at
29236 @item @code{node-schedule} (default: @code{"45 2 * * *"})
29237 How often to run the node cleaning job. The default is once per day, at
29243 @node Version Control Services
29244 @subsection Version Control Services
29246 The @code{(gnu services version-control)} module provides a service to
29247 allow remote access to local Git repositories. There are three options:
29248 the @code{git-daemon-service}, which provides access to repositories via
29249 the @code{git://} unsecured TCP-based protocol, extending the
29250 @code{nginx} web server to proxy some requests to
29251 @code{git-http-backend}, or providing a web interface with
29252 @code{cgit-service-type}.
29254 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
29256 Return a service that runs @command{git daemon}, a simple TCP server to
29257 expose repositories over the Git protocol for anonymous access.
29259 The optional @var{config} argument should be a
29260 @code{<git-daemon-configuration>} object, by default it allows read-only
29261 access to exported@footnote{By creating the magic file
29262 @file{git-daemon-export-ok} in the repository directory.} repositories under
29267 @deftp {Data Type} git-daemon-configuration
29268 Data type representing the configuration for @code{git-daemon-service}.
29271 @item @code{package} (default: @code{git})
29272 Package object of the Git distributed version control system.
29274 @item @code{export-all?} (default: @code{#f})
29275 Whether to allow access for all Git repositories, even if they do not
29276 have the @file{git-daemon-export-ok} file.
29278 @item @code{base-path} (default: @file{/srv/git})
29279 Whether to remap all the path requests as relative to the given path.
29280 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
29281 @samp{example.com}, then if you later try to pull
29282 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
29283 path as @file{/srv/git/hello.git}.
29285 @item @code{user-path} (default: @code{#f})
29286 Whether to allow @code{~user} notation to be used in requests. When
29287 specified with empty string, requests to
29288 @indicateurl{git://host/~alice/foo} is taken as a request to access
29289 @code{foo} repository in the home directory of user @code{alice}. If
29290 @code{(user-path "@var{path}")} is specified, the same request is taken
29291 as a request to access @file{@var{path}/foo} repository in the home
29292 directory of user @code{alice}.
29294 @item @code{listen} (default: @code{'()})
29295 Whether to listen on specific IP addresses or hostnames, defaults to
29298 @item @code{port} (default: @code{#f})
29299 Whether to listen on an alternative port, which defaults to 9418.
29301 @item @code{whitelist} (default: @code{'()})
29302 If not empty, only allow access to this list of directories.
29304 @item @code{extra-options} (default: @code{'()})
29305 Extra options will be passed to @command{git daemon}, please run
29306 @command{man git-daemon} for more information.
29311 The @code{git://} protocol lacks authentication. When you pull from a
29312 repository fetched via @code{git://}, you don't know whether the data you
29313 receive was modified or is even coming from the specified host, and your
29314 connection is subject to eavesdropping. It's better to use an authenticated
29315 and encrypted transport, such as @code{https}. Although Git allows you
29316 to serve repositories using unsophisticated file-based web servers,
29317 there is a faster protocol implemented by the @code{git-http-backend}
29318 program. This program is the back-end of a proper Git web service. It
29319 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
29320 on running the necessary @code{fcgiwrap} daemon.
29322 Guix has a separate configuration data type for serving Git repositories
29325 @deftp {Data Type} git-http-configuration
29326 Data type representing the configuration for a future
29327 @code{git-http-service-type}; can currently be used to configure Nginx
29328 through @code{git-http-nginx-location-configuration}.
29331 @item @code{package} (default: @var{git})
29332 Package object of the Git distributed version control system.
29334 @item @code{git-root} (default: @file{/srv/git})
29335 Directory containing the Git repositories to expose to the world.
29337 @item @code{export-all?} (default: @code{#f})
29338 Whether to expose access for all Git repositories in @var{git-root},
29339 even if they do not have the @file{git-daemon-export-ok} file.
29341 @item @code{uri-path} (default: @samp{/git/})
29342 Path prefix for Git access. With the default @samp{/git/} prefix, this
29343 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
29344 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
29345 with this prefix are not passed on to this Git instance.
29347 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
29348 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
29353 There is no @code{git-http-service-type}, currently; instead you can
29354 create an @code{nginx-location-configuration} from a
29355 @code{git-http-configuration} and then add that location to a web
29358 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
29359 [config=(git-http-configuration)]
29360 Compute an @code{nginx-location-configuration} that corresponds to the
29361 given Git http configuration. An example nginx service definition to
29362 serve the default @file{/srv/git} over HTTPS might be:
29365 (service nginx-service-type
29366 (nginx-configuration
29369 (nginx-server-configuration
29370 (listen '("443 ssl"))
29371 (server-name "git.my-host.org")
29373 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
29374 (ssl-certificate-key
29375 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
29378 (git-http-nginx-location-configuration
29379 (git-http-configuration (uri-path "/"))))))))))
29382 This example assumes that you are using Let's Encrypt to get your TLS
29383 certificate. @xref{Certificate Services}. The default @code{certbot}
29384 service will redirect all HTTP traffic on @code{git.my-host.org} to
29385 HTTPS@. You will also need to add an @code{fcgiwrap} proxy to your
29386 system services. @xref{Web Services}.
29389 @subsubheading Cgit Service
29391 @cindex Cgit service
29392 @cindex Git, web interface
29393 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
29394 repositories written in C.
29396 The following example will configure the service with default values.
29397 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
29400 (service cgit-service-type)
29403 The @code{file-object} type designates either a file-like object
29404 (@pxref{G-Expressions, file-like objects}) or a string.
29406 @c %start of fragment
29408 Available @code{cgit-configuration} fields are:
29410 @deftypevr {@code{cgit-configuration} parameter} package package
29415 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
29416 NGINX configuration.
29420 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
29421 Specifies a command which will be invoked to format the content of about
29422 pages (both top-level and for each repository).
29424 Defaults to @samp{""}.
29428 @deftypevr {@code{cgit-configuration} parameter} string agefile
29429 Specifies a path, relative to each repository path, which can be used to
29430 specify the date and time of the youngest commit in the repository.
29432 Defaults to @samp{""}.
29436 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
29437 Specifies a command that will be invoked for authenticating repository
29440 Defaults to @samp{""}.
29444 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
29445 Flag which, when set to @samp{age}, enables date ordering in the branch
29446 ref list, and when set @samp{name} enables ordering by branch name.
29448 Defaults to @samp{"name"}.
29452 @deftypevr {@code{cgit-configuration} parameter} string cache-root
29453 Path used to store the cgit cache entries.
29455 Defaults to @samp{"/var/cache/cgit"}.
29459 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
29460 Number which specifies the time-to-live, in minutes, for the cached
29461 version of repository pages accessed with a fixed SHA1.
29463 Defaults to @samp{-1}.
29467 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
29468 Number which specifies the time-to-live, in minutes, for the cached
29469 version of repository pages accessed without a fixed SHA1.
29471 Defaults to @samp{5}.
29475 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
29476 Number which specifies the time-to-live, in minutes, for the cached
29477 version of the repository summary page.
29479 Defaults to @samp{5}.
29483 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
29484 Number which specifies the time-to-live, in minutes, for the cached
29485 version of the repository index page.
29487 Defaults to @samp{5}.
29491 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
29492 Number which specifies the time-to-live, in minutes, for the result of
29493 scanning a path for Git repositories.
29495 Defaults to @samp{15}.
29499 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
29500 Number which specifies the time-to-live, in minutes, for the cached
29501 version of the repository about page.
29503 Defaults to @samp{15}.
29507 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
29508 Number which specifies the time-to-live, in minutes, for the cached
29509 version of snapshots.
29511 Defaults to @samp{5}.
29515 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
29516 The maximum number of entries in the cgit cache. When set to @samp{0},
29517 caching is disabled.
29519 Defaults to @samp{0}.
29523 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
29524 Sort items in the repo list case sensitively.
29526 Defaults to @samp{#t}.
29530 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
29531 List of common prefixes which, when combined with a repository URL,
29532 generates valid clone URLs for the repository.
29534 Defaults to @samp{()}.
29538 @deftypevr {@code{cgit-configuration} parameter} list clone-url
29539 List of @code{clone-url} templates.
29541 Defaults to @samp{()}.
29545 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
29546 Command which will be invoked to format commit messages.
29548 Defaults to @samp{""}.
29552 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
29553 Flag which, when set to @samp{date}, enables strict date ordering in the
29554 commit log, and when set to @samp{topo} enables strict topological
29557 Defaults to @samp{"git log"}.
29561 @deftypevr {@code{cgit-configuration} parameter} file-object css
29562 URL which specifies the css document to include in all cgit pages.
29564 Defaults to @samp{"/share/cgit/cgit.css"}.
29568 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
29569 Specifies a command which will be invoked to format names and email
29570 address of committers, authors, and taggers, as represented in various
29571 places throughout the cgit interface.
29573 Defaults to @samp{""}.
29577 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
29578 Flag which, when set to @samp{#t}, will make cgit generate a HTML
29579 fragment suitable for embedding in other HTML pages.
29581 Defaults to @samp{#f}.
29585 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
29586 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
29587 commit history graph to the left of the commit messages in the
29588 repository log page.
29590 Defaults to @samp{#f}.
29594 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
29595 Flag which, when set to @samp{#t}, allows all filter settings to be
29596 overridden in repository-specific cgitrc files.
29598 Defaults to @samp{#f}.
29602 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
29603 Flag which, when set to @samp{#t}, allows users to follow a file in the
29606 Defaults to @samp{#f}.
29610 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
29611 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
29614 Defaults to @samp{#t}.
29618 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
29619 Flag which, when set to @samp{#t}, will make cgit generate extra links
29620 "summary", "commit", "tree" for each repo in the repository index.
29622 Defaults to @samp{#f}.
29626 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
29627 Flag which, when set to @samp{#t}, will make cgit display the owner of
29628 each repo in the repository index.
29630 Defaults to @samp{#t}.
29634 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
29635 Flag which, when set to @samp{#t}, will make cgit print the number of
29636 modified files for each commit on the repository log page.
29638 Defaults to @samp{#f}.
29642 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
29643 Flag which, when set to @samp{#t}, will make cgit print the number of
29644 added and removed lines for each commit on the repository log page.
29646 Defaults to @samp{#f}.
29650 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
29651 Flag which, when set to @code{#t}, will make cgit display remote
29652 branches in the summary and refs views.
29654 Defaults to @samp{#f}.
29658 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
29659 Flag which, when set to @code{1}, will make cgit use the subject of the
29660 parent commit as link text when generating links to parent commits in
29663 Defaults to @samp{#f}.
29667 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
29668 Flag which, when set to @samp{#t}, will make cgit use the subject of the
29669 parent commit as link text when generating links to parent commits in
29672 Defaults to @samp{#f}.
29676 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
29677 Flag which, when set to @samp{#t}, will make cgit generate linenumber
29678 links for plaintext blobs printed in the tree view.
29680 Defaults to @samp{#t}.
29684 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
29685 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
29686 set any repo specific settings.
29688 Defaults to @samp{#f}.
29692 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
29693 URL used as link to a shortcut icon for cgit.
29695 Defaults to @samp{"/favicon.ico"}.
29699 @deftypevr {@code{cgit-configuration} parameter} string footer
29700 The content of the file specified with this option will be included
29701 verbatim at the bottom of all pages (i.e.@: it replaces the standard
29702 "generated by..."@: message).
29704 Defaults to @samp{""}.
29708 @deftypevr {@code{cgit-configuration} parameter} string head-include
29709 The content of the file specified with this option will be included
29710 verbatim in the HTML HEAD section on all pages.
29712 Defaults to @samp{""}.
29716 @deftypevr {@code{cgit-configuration} parameter} string header
29717 The content of the file specified with this option will be included
29718 verbatim at the top of all pages.
29720 Defaults to @samp{""}.
29724 @deftypevr {@code{cgit-configuration} parameter} file-object include
29725 Name of a configfile to include before the rest of the current config-
29728 Defaults to @samp{""}.
29732 @deftypevr {@code{cgit-configuration} parameter} string index-header
29733 The content of the file specified with this option will be included
29734 verbatim above the repository index.
29736 Defaults to @samp{""}.
29740 @deftypevr {@code{cgit-configuration} parameter} string index-info
29741 The content of the file specified with this option will be included
29742 verbatim below the heading on the repository index page.
29744 Defaults to @samp{""}.
29748 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
29749 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
29750 in the servers timezone.
29752 Defaults to @samp{#f}.
29756 @deftypevr {@code{cgit-configuration} parameter} file-object logo
29757 URL which specifies the source of an image which will be used as a logo
29760 Defaults to @samp{"/share/cgit/cgit.png"}.
29764 @deftypevr {@code{cgit-configuration} parameter} string logo-link
29765 URL loaded when clicking on the cgit logo image.
29767 Defaults to @samp{""}.
29771 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
29772 Command which will be invoked to format the Owner column of the main
29775 Defaults to @samp{""}.
29779 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
29780 Number of items to display in atom feeds view.
29782 Defaults to @samp{10}.
29786 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
29787 Number of entries to list per page in "log" view.
29789 Defaults to @samp{50}.
29793 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
29794 Number of commit message characters to display in "log" view.
29796 Defaults to @samp{80}.
29800 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
29801 Specifies the number of entries to list per page on the repository index
29804 Defaults to @samp{50}.
29808 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
29809 Specifies the maximum number of repo description characters to display
29810 on the repository index page.
29812 Defaults to @samp{80}.
29816 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
29817 Specifies the maximum size of a blob to display HTML for in KBytes.
29819 Defaults to @samp{0}.
29823 @deftypevr {@code{cgit-configuration} parameter} string max-stats
29824 Maximum statistics period. Valid values are @samp{week},@samp{month},
29825 @samp{quarter} and @samp{year}.
29827 Defaults to @samp{""}.
29831 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
29832 Mimetype for the specified filename extension.
29834 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
29835 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
29836 "image/png") (svg "image/svg+xml"))}.
29840 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
29841 Specifies the file to use for automatic mimetype lookup.
29843 Defaults to @samp{""}.
29847 @deftypevr {@code{cgit-configuration} parameter} string module-link
29848 Text which will be used as the formatstring for a hyperlink when a
29849 submodule is printed in a directory listing.
29851 Defaults to @samp{""}.
29855 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
29856 If set to the value @samp{#t} caching will be disabled.
29858 Defaults to @samp{#f}.
29862 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
29863 If set to @samp{#t} showing full author email addresses will be
29866 Defaults to @samp{#f}.
29870 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
29871 Flag which, when set to @samp{#t}, will make cgit omit the standard
29872 header on all pages.
29874 Defaults to @samp{#f}.
29878 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
29879 A list of subdirectories inside of @code{repository-directory}, relative
29880 to it, that should loaded as Git repositories. An empty list means that
29881 all subdirectories will be loaded.
29883 Defaults to @samp{()}.
29887 @deftypevr {@code{cgit-configuration} parameter} file-object readme
29888 Text which will be used as default value for @code{cgit-repo-readme}.
29890 Defaults to @samp{""}.
29894 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
29895 If set to @code{#t} and @code{repository-directory} is enabled, if any
29896 repositories are found with a suffix of @code{.git}, this suffix will be
29897 removed for the URL and name.
29899 Defaults to @samp{#f}.
29903 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
29904 Maximum number of files to consider when detecting renames.
29906 Defaults to @samp{-1}.
29910 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
29911 The way in which repositories in each section are sorted.
29913 Defaults to @samp{""}.
29917 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
29918 Text used as content for the @code{robots} meta-tag.
29920 Defaults to @samp{("noindex" "nofollow")}.
29924 @deftypevr {@code{cgit-configuration} parameter} string root-desc
29925 Text printed below the heading on the repository index page.
29927 Defaults to @samp{"a fast webinterface for the git dscm"}.
29931 @deftypevr {@code{cgit-configuration} parameter} string root-readme
29932 The content of the file specified with this option will be included
29933 verbatim below the ``about'' link on the repository index page.
29935 Defaults to @samp{""}.
29939 @deftypevr {@code{cgit-configuration} parameter} string root-title
29940 Text printed as heading on the repository index page.
29942 Defaults to @samp{""}.
29946 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
29947 If set to @samp{#t} and repository-directory is enabled,
29948 repository-directory will recurse into directories whose name starts
29949 with a period. Otherwise, repository-directory will stay away from such
29950 directories, considered as ``hidden''. Note that this does not apply to
29951 the @file{.git} directory in non-bare repos.
29953 Defaults to @samp{#f}.
29957 @deftypevr {@code{cgit-configuration} parameter} list snapshots
29958 Text which specifies the default set of snapshot formats that cgit
29959 generates links for.
29961 Defaults to @samp{()}.
29965 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
29966 Name of the directory to scan for repositories (represents
29969 Defaults to @samp{"/srv/git"}.
29973 @deftypevr {@code{cgit-configuration} parameter} string section
29974 The name of the current repository section - all repositories defined
29975 after this option will inherit the current section name.
29977 Defaults to @samp{""}.
29981 @deftypevr {@code{cgit-configuration} parameter} string section-sort
29982 Flag which, when set to @samp{1}, will sort the sections on the
29983 repository listing by name.
29985 Defaults to @samp{""}.
29989 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
29990 A number which, if defined prior to repository-directory, specifies how
29991 many path elements from each repo path to use as a default section name.
29993 Defaults to @samp{0}.
29997 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
29998 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
30001 Defaults to @samp{#f}.
30005 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
30006 Specifies a command which will be invoked to format plaintext blobs in
30009 Defaults to @samp{""}.
30013 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
30014 Specifies the number of branches to display in the repository ``summary''
30017 Defaults to @samp{10}.
30021 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
30022 Specifies the number of log entries to display in the repository
30025 Defaults to @samp{10}.
30029 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
30030 Specifies the number of tags to display in the repository ``summary''
30033 Defaults to @samp{10}.
30037 @deftypevr {@code{cgit-configuration} parameter} string strict-export
30038 Filename which, if specified, needs to be present within the repository
30039 for cgit to allow access to that repository.
30041 Defaults to @samp{""}.
30045 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
30046 URL which, if specified, will be used as root for all cgit links.
30048 Defaults to @samp{"/"}.
30052 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
30053 A list of @dfn{cgit-repo} records to use with config.
30055 Defaults to @samp{()}.
30057 Available @code{repository-cgit-configuration} fields are:
30059 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
30060 A mask of snapshot formats for this repo that cgit generates links for,
30061 restricted by the global @code{snapshots} setting.
30063 Defaults to @samp{()}.
30067 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
30068 Override the default @code{source-filter}.
30070 Defaults to @samp{""}.
30074 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
30075 The relative URL used to access the repository.
30077 Defaults to @samp{""}.
30081 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
30082 Override the default @code{about-filter}.
30084 Defaults to @samp{""}.
30088 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
30089 Flag which, when set to @samp{age}, enables date ordering in the branch
30090 ref list, and when set to @samp{name} enables ordering by branch name.
30092 Defaults to @samp{""}.
30096 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
30097 A list of URLs which can be used to clone repo.
30099 Defaults to @samp{()}.
30103 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
30104 Override the default @code{commit-filter}.
30106 Defaults to @samp{""}.
30110 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
30111 Flag which, when set to @samp{date}, enables strict date ordering in the
30112 commit log, and when set to @samp{topo} enables strict topological
30115 Defaults to @samp{""}.
30119 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
30120 The name of the default branch for this repository. If no such branch
30121 exists in the repository, the first branch name (when sorted) is used as
30122 default instead. By default branch pointed to by HEAD, or ``master'' if
30123 there is no suitable HEAD.
30125 Defaults to @samp{""}.
30129 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
30130 The value to show as repository description.
30132 Defaults to @samp{""}.
30136 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
30137 The value to show as repository homepage.
30139 Defaults to @samp{""}.
30143 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
30144 Override the default @code{email-filter}.
30146 Defaults to @samp{""}.
30150 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
30151 A flag which can be used to disable the global setting
30152 @code{enable-commit-graph?}.
30154 Defaults to @samp{disabled}.
30158 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
30159 A flag which can be used to disable the global setting
30160 @code{enable-log-filecount?}.
30162 Defaults to @samp{disabled}.
30166 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
30167 A flag which can be used to disable the global setting
30168 @code{enable-log-linecount?}.
30170 Defaults to @samp{disabled}.
30174 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
30175 Flag which, when set to @code{#t}, will make cgit display remote
30176 branches in the summary and refs views.
30178 Defaults to @samp{disabled}.
30182 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
30183 A flag which can be used to override the global setting
30184 @code{enable-subject-links?}.
30186 Defaults to @samp{disabled}.
30190 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
30191 A flag which can be used to override the global setting
30192 @code{enable-html-serving?}.
30194 Defaults to @samp{disabled}.
30198 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
30199 Flag which, when set to @code{#t}, hides the repository from the
30202 Defaults to @samp{#f}.
30206 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
30207 Flag which, when set to @samp{#t}, ignores the repository.
30209 Defaults to @samp{#f}.
30213 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
30214 URL which specifies the source of an image which will be used as a logo
30215 on this repo’s pages.
30217 Defaults to @samp{""}.
30221 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
30222 URL loaded when clicking on the cgit logo image.
30224 Defaults to @samp{""}.
30228 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
30229 Override the default @code{owner-filter}.
30231 Defaults to @samp{""}.
30235 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
30236 Text which will be used as the formatstring for a hyperlink when a
30237 submodule is printed in a directory listing. The arguments for the
30238 formatstring are the path and SHA1 of the submodule commit.
30240 Defaults to @samp{""}.
30244 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
30245 Text which will be used as the formatstring for a hyperlink when a
30246 submodule with the specified subdirectory path is printed in a directory
30249 Defaults to @samp{()}.
30253 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
30254 Override the default maximum statistics period.
30256 Defaults to @samp{""}.
30260 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
30261 The value to show as repository name.
30263 Defaults to @samp{""}.
30267 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
30268 A value used to identify the owner of the repository.
30270 Defaults to @samp{""}.
30274 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
30275 An absolute path to the repository directory.
30277 Defaults to @samp{""}.
30281 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
30282 A path (relative to repo) which specifies a file to include verbatim as
30283 the ``About'' page for this repo.
30285 Defaults to @samp{""}.
30289 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
30290 The name of the current repository section - all repositories defined
30291 after this option will inherit the current section name.
30293 Defaults to @samp{""}.
30297 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
30298 Extra options will be appended to cgitrc file.
30300 Defaults to @samp{()}.
30306 @deftypevr {@code{cgit-configuration} parameter} list extra-options
30307 Extra options will be appended to cgitrc file.
30309 Defaults to @samp{()}.
30314 @c %end of fragment
30316 However, it could be that you just want to get a @code{cgitrc} up and
30317 running. In that case, you can pass an @code{opaque-cgit-configuration}
30318 as a record to @code{cgit-service-type}. As its name indicates, an
30319 opaque configuration does not have easy reflective capabilities.
30321 Available @code{opaque-cgit-configuration} fields are:
30323 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
30327 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
30328 The contents of the @code{cgitrc}, as a string.
30331 For example, if your @code{cgitrc} is just the empty string, you
30332 could instantiate a cgit service like this:
30335 (service cgit-service-type
30336 (opaque-cgit-configuration
30340 @subsubheading Gitolite Service
30342 @cindex Gitolite service
30343 @cindex Git, hosting
30344 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
30345 repositories on a central server.
30347 Gitolite can handle multiple repositories and users, and supports flexible
30348 configuration of the permissions for the users on the repositories.
30350 The following example will configure Gitolite using the default @code{git}
30351 user, and the provided SSH public key.
30354 (service gitolite-service-type
30355 (gitolite-configuration
30356 (admin-pubkey (plain-file
30358 "ssh-rsa AAAA... guix@@example.com"))))
30361 Gitolite is configured through a special admin repository which you can clone,
30362 for example, if you setup Gitolite on @code{example.com}, you would run the
30363 following command to clone the admin repository.
30366 git clone git@@example.com:gitolite-admin
30369 When the Gitolite service is activated, the provided @code{admin-pubkey} will
30370 be inserted in to the @file{keydir} directory in the gitolite-admin
30371 repository. If this results in a change in the repository, it will be
30372 committed using the message ``gitolite setup by GNU Guix''.
30374 @deftp {Data Type} gitolite-configuration
30375 Data type representing the configuration for @code{gitolite-service-type}.
30378 @item @code{package} (default: @var{gitolite})
30379 Gitolite package to use.
30381 @item @code{user} (default: @var{git})
30382 User to use for Gitolite. This will be user that you use when accessing
30385 @item @code{group} (default: @var{git})
30386 Group to use for Gitolite.
30388 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
30389 Directory in which to store the Gitolite configuration and repositories.
30391 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
30392 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
30393 representing the configuration for Gitolite.
30395 @item @code{admin-pubkey} (default: @var{#f})
30396 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
30397 setup Gitolite. This will be inserted in to the @file{keydir} directory
30398 within the gitolite-admin repository.
30400 To specify the SSH key as a string, use the @code{plain-file} function.
30403 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
30409 @deftp {Data Type} gitolite-rc-file
30410 Data type representing the Gitolite RC file.
30413 @item @code{umask} (default: @code{#o0077})
30414 This controls the permissions Gitolite sets on the repositories and their
30417 A value like @code{#o0027} will give read access to the group used by Gitolite
30418 (by default: @code{git}). This is necessary when using Gitolite with software
30419 like cgit or gitweb.
30421 @item @code{git-config-keys} (default: @code{""})
30422 Gitolite allows you to set git config values using the @samp{config}
30423 keyword. This setting allows control over the config keys to accept.
30425 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
30426 Set the role names allowed to be used by users running the perms command.
30428 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
30429 This setting controls the commands and features to enable within Gitolite.
30435 @node Game Services
30436 @subsection Game Services
30438 @subsubheading The Battle for Wesnoth Service
30440 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
30441 based tactical strategy game, with several single player campaigns, and
30442 multiplayer games (both networked and local).
30444 @defvar {Scheme Variable} wesnothd-service-type
30445 Service type for the wesnothd service. Its value must be a
30446 @code{wesnothd-configuration} object. To run wesnothd in the default
30447 configuration, instantiate it as:
30450 (service wesnothd-service-type)
30454 @deftp {Data Type} wesnothd-configuration
30455 Data type representing the configuration of @command{wesnothd}.
30458 @item @code{package} (default: @code{wesnoth-server})
30459 The wesnoth server package to use.
30461 @item @code{port} (default: @code{15000})
30462 The port to bind the server to.
30467 @node PAM Mount Service
30468 @subsection PAM Mount Service
30471 The @code{(gnu services pam-mount)} module provides a service allowing
30472 users to mount volumes when they log in. It should be able to mount any
30473 volume format supported by the system.
30475 @defvar {Scheme Variable} pam-mount-service-type
30476 Service type for PAM Mount support.
30479 @deftp {Data Type} pam-mount-configuration
30480 Data type representing the configuration of PAM Mount.
30482 It takes the following parameters:
30486 The configuration rules that will be used to generate
30487 @file{/etc/security/pam_mount.conf.xml}.
30489 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
30490 Guile Reference Manual}), and the default ones don't mount anything for
30494 `((debug (@@ (enable "0")))
30495 (mntoptions (@@ (allow ,(string-join
30496 '("nosuid" "nodev" "loop"
30497 "encryption" "fsck" "nonempty"
30498 "allow_root" "allow_other")
30500 (mntoptions (@@ (require "nosuid,nodev")))
30501 (logout (@@ (wait "0")
30505 (mkmountpoint (@@ (enable "1")
30509 Some @code{volume} elements must be added to automatically mount volumes
30510 at login. Here's an example allowing the user @code{alice} to mount her
30511 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
30512 the partition where he stores his data:
30515 (define pam-mount-rules
30516 `((debug (@@ (enable "0")))
30517 (volume (@@ (user "alice")
30520 (mountpoint "/home/alice")))
30521 (volume (@@ (user "bob")
30524 (mountpoint "/home/bob/data")
30525 (options "defaults,autodefrag,compress")))
30526 (mntoptions (@@ (allow ,(string-join
30527 '("nosuid" "nodev" "loop"
30528 "encryption" "fsck" "nonempty"
30529 "allow_root" "allow_other")
30531 (mntoptions (@@ (require "nosuid,nodev")))
30532 (logout (@@ (wait "0")
30536 (mkmountpoint (@@ (enable "1")
30537 (remove "true")))))
30539 (service pam-mount-service-type
30540 (pam-mount-configuration
30541 (rules pam-mount-rules)))
30544 The complete list of possible options can be found in the man page for
30545 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
30550 @node Guix Services
30551 @subsection Guix Services
30553 @subsubheading Guix Build Coordinator
30554 The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
30555 Coordinator} aids in distributing derivation builds among machines
30556 running an @dfn{agent}. The build daemon is still used to build the
30557 derivations, but the Guix Build Coordinator manages allocating builds
30558 and working with the results.
30561 This service is considered experimental. Configuration options may be
30562 changed in a backwards-incompatible manner, and not all features have
30563 been thorougly tested.
30566 The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
30567 more connected @dfn{agent} processes. The coordinator process handles
30568 clients submitting builds, and allocating builds to agents. The agent
30569 processes talk to a build daemon to actually perform the builds, then
30570 send the results back to the coordinator.
30572 There is a script to run the coordinator component of the Guix Build
30573 Coordinator, but the Guix service uses a custom Guile script instead, to
30574 provide better integration with G-expressions used in the configuration.
30576 @defvar {Scheme Variable} guix-build-coordinator-service-type
30577 Service type for the Guix Build Coordinator. Its value must be a
30578 @code{guix-build-coordinator-configuration} object.
30581 @deftp {Data Type} guix-build-coordinator-configuration
30582 Data type representing the configuration of the Guix Build Coordinator.
30585 @item @code{package} (default: @code{guix-build-coordinator})
30586 The Guix Build Coordinator package to use.
30588 @item @code{user} (default: @code{"guix-build-coordinator"})
30589 The system user to run the service as.
30591 @item @code{group} (default: @code{"guix-build-coordinator"})
30592 The system group to run the service as.
30594 @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
30595 The URI to use for the database.
30597 @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
30598 The URI describing how to listen to requests from agent processes.
30600 @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
30601 The URI describing how to listen to requests from clients. The client
30602 API allows submitting builds and currently isn't authenticated, so take
30603 care when configuring this value.
30605 @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
30606 A G-expression for the allocation strategy to be used. This is a
30607 procedure that takes the datastore as an argument and populates the
30608 allocation plan in the database.
30610 @item @code{hooks} (default: @var{'()})
30611 An association list of hooks. These provide a way to execute arbitrary
30612 code upon certain events, like a build result being processed.
30614 @item @code{guile} (default: @code{guile-3.0-latest})
30615 The Guile package with which to run the Guix Build Coordinator.
30620 @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
30621 Service type for a Guix Build Coordinator agent. Its value must be a
30622 @code{guix-build-coordinator-agent-configuration} object.
30625 @deftp {Data Type} guix-build-coordinator-agent-configuration
30626 Data type representing the configuration a Guix Build Coordinator agent.
30629 @item @code{package} (default: @code{guix-build-coordinator})
30630 The Guix Build Coordinator package to use.
30632 @item @code{user} (default: @code{"guix-build-coordinator-agent"})
30633 The system user to run the service as.
30635 @item @code{coordinator} (default: @code{"http://localhost:8745"})
30636 The URI to use when connecting to the coordinator.
30639 The UUID of the agent. This should be generated by the coordinator
30640 process, stored in the coordinator database, and used by the intended
30643 @item @code{password} (default: @code{#f})
30644 The password to use when connecting to the coordinator. A file to read
30645 the password from can also be specified, and this is more secure.
30647 @item @code{password-file} (default: @code{#f})
30648 A file containing the password to use when connecting to the
30651 @item @code{systems} (default: @code{#f})
30652 The systems for which this agent should fetch builds. The agent process
30653 will use the current system it's running on as the default.
30655 @item @code{max-parallel-builds} (default: @code{1})
30656 The number of builds to perform in parallel.
30658 @item @code{derivation-substitute-urls} (default: @code{#f})
30659 URLs from which to attempt to fetch substitutes for derivations, if the
30660 derivations aren't already available.
30662 @item @code{non-derivation-substitute-urls} (default: @code{#f})
30663 URLs from which to attempt to fetch substitutes for build inputs, if the
30664 input store items aren't already available.
30669 The Guix Build Coordinator package contains a script to query an
30670 instance of the Guix Data Service for derivations to build, and then
30671 submit builds for those derivations to the coordinator. The service
30672 type below assists in running this script. This is an additional tool
30673 that may be useful when building derivations contained within an
30674 instance of the Guix Data Service.
30676 @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
30677 Service type for the
30678 guix-build-coordinator-queue-builds-from-guix-data-service script. Its
30679 value must be a @code{guix-build-coordinator-queue-builds-configuration}
30683 @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
30684 Data type representing the options to the queue builds from guix data
30688 @item @code{package} (default: @code{guix-build-coordinator})
30689 The Guix Build Coordinator package to use.
30691 @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
30692 The system user to run the service as.
30694 @item @code{coordinator} (default: @code{"http://localhost:8745"})
30695 The URI to use when connecting to the coordinator.
30697 @item @code{systems} (default: @code{#f})
30698 The systems for which to fetch derivations to build.
30700 @item @code{systems-and-targets} (default: @code{#f})
30701 An association list of system and target pairs for which to fetch
30702 derivations to build.
30704 @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
30705 The Guix Data Service instance from which to query to find out about
30706 derivations to build.
30708 @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
30709 A file to record which commits have been processed, to avoid needlessly
30710 processing them again if the service is restarted.
30715 @subsubheading Guix Data Service
30716 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
30717 and provides data about GNU Guix. This includes information about
30718 packages, derivations and lint warnings.
30720 The data is stored in a PostgreSQL database, and available through a web
30723 @defvar {Scheme Variable} guix-data-service-type
30724 Service type for the Guix Data Service. Its value must be a
30725 @code{guix-data-service-configuration} object. The service optionally
30726 extends the getmail service, as the guix-commits mailing list is used to
30727 find out about changes in the Guix git repository.
30730 @deftp {Data Type} guix-data-service-configuration
30731 Data type representing the configuration of the Guix Data Service.
30734 @item @code{package} (default: @code{guix-data-service})
30735 The Guix Data Service package to use.
30737 @item @code{user} (default: @code{"guix-data-service"})
30738 The system user to run the service as.
30740 @item @code{group} (default: @code{"guix-data-service"})
30741 The system group to run the service as.
30743 @item @code{port} (default: @code{8765})
30744 The port to bind the web service to.
30746 @item @code{host} (default: @code{"127.0.0.1"})
30747 The host to bind the web service to.
30749 @item @code{getmail-idle-mailboxes} (default: @code{#f})
30750 If set, this is the list of mailboxes that the getmail service will be
30751 configured to listen to.
30753 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
30754 If set, this is the @code{getmail-retriever-configuration} object with
30755 which to configure getmail to fetch mail from the guix-commits mailing
30758 @item @code{extra-options} (default: @var{'()})
30759 Extra command line options for @code{guix-data-service}.
30761 @item @code{extra-process-jobs-options} (default: @var{'()})
30762 Extra command line options for @code{guix-data-service-process-jobs}.
30767 @node Linux Services
30768 @subsection Linux Services
30771 @cindex out of memory killer
30773 @cindex early out of memory daemon
30774 @subsubheading Early OOM Service
30776 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
30777 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
30778 space and provides a more responsive and configurable alternative to the
30779 in-kernel OOM killer. It is useful to prevent the system from becoming
30780 unresponsive when it runs out of memory.
30782 @deffn {Scheme Variable} earlyoom-service-type
30783 The service type for running @command{earlyoom}, the Early OOM daemon.
30784 Its value must be a @code{earlyoom-configuration} object, described
30785 below. The service can be instantiated in its default configuration
30789 (service earlyoom-service-type)
30793 @deftp {Data Type} earlyoom-configuration
30794 This is the configuration record for the @code{earlyoom-service-type}.
30797 @item @code{earlyoom} (default: @var{earlyoom})
30798 The Earlyoom package to use.
30800 @item @code{minimum-available-memory} (default: @code{10})
30801 The threshold for the minimum @emph{available} memory, in percentages.
30803 @item @code{minimum-free-swap} (default: @code{10})
30804 The threshold for the minimum free swap memory, in percentages.
30806 @item @code{prefer-regexp} (default: @code{#f})
30807 A regular expression (as a string) to match the names of the processes
30808 that should be preferably killed.
30810 @item @code{avoid-regexp} (default: @code{#f})
30811 A regular expression (as a string) to match the names of the processes
30812 that should @emph{not} be killed.
30814 @item @code{memory-report-interval} (default: @code{0})
30815 The interval in seconds at which a memory report is printed. It is
30816 disabled by default.
30818 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
30819 A boolean indicating whether the positive adjustments set in
30820 @file{/proc/*/oom_score_adj} should be ignored.
30822 @item @code{show-debug-messages?} (default: @code{#f})
30823 A boolean indicating whether debug messages should be printed. The logs
30824 are saved at @file{/var/log/earlyoom.log}.
30826 @item @code{send-notification-command} (default: @code{#f})
30827 This can be used to provide a custom command used for sending
30833 @cindex kernel module loader
30834 @subsubheading Kernel Module Loader Service
30836 The kernel module loader service allows one to load loadable kernel
30837 modules at boot. This is especially useful for modules that don't
30838 autoload and need to be manually loaded, as it's the case with
30841 @deffn {Scheme Variable} kernel-module-loader-service-type
30842 The service type for loading loadable kernel modules at boot with
30843 @command{modprobe}. Its value must be a list of strings representing
30844 module names. For example loading the drivers provided by
30845 @code{ddcci-driver-linux}, in debugging mode by passing some module
30846 parameters, can be done as follow:
30849 (use-modules (gnu) (gnu services))
30850 (use-package-modules linux)
30851 (use-service-modules linux)
30853 (define ddcci-config
30854 (plain-file "ddcci.conf"
30855 "options ddcci dyndbg delay=120"))
30859 (services (cons* (service kernel-module-loader-service-type
30860 '("ddcci" "ddcci_backlight"))
30861 (simple-service 'ddcci-config etc-service-type
30862 (list `("modprobe.d/ddcci.conf"
30865 (kernel-loadable-modules (list ddcci-driver-linux)))
30870 @cindex compressed swap
30871 @cindex Compressed RAM-based block devices
30872 @subsubheading Zram Device Service
30874 The Zram device service provides a compressed swap device in system
30875 memory. The Linux Kernel documentation has more information about
30876 @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
30879 @deffn {Scheme Variable} zram-device-service-type
30880 This service creates the zram block device, formats it as swap and
30881 enables it as a swap device. The service's value is a
30882 @code{zram-device-configuration} record.
30884 @deftp {Data Type} zram-device-configuration
30885 This is the data type representing the configuration for the zram-device
30889 @item @code{size} (default @code{"1G"})
30890 This is the amount of space you wish to provide for the zram device. It
30891 accepts a string and can be a number of bytes or use a suffix, eg.:
30892 @code{"512M"} or @code{1024000}.
30893 @item @code{compression-algorithm} (default @code{'lzo})
30894 This is the compression algorithm you wish to use. It is difficult to
30895 list all the possible compression options, but common ones supported by
30896 Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
30897 @item @code{memory-limit} (default @code{0})
30898 This is the maximum amount of memory which the zram device can use.
30899 Setting it to '0' disables the limit. While it is generally expected
30900 that compression will be 2:1, it is possible that uncompressable data
30901 can be written to swap and this is a method to limit how much memory can
30902 be used. It accepts a string and can be a number of bytes or use a
30903 suffix, eg.: @code{"2G"}.
30904 @item @code{priority} (default @code{-1})
30905 This is the priority of the swap device created from the zram device.
30906 @code{swapon} accepts values between -1 and 32767, with higher values
30907 indicating higher priority. Higher priority swap will generally be used
30914 @node Hurd Services
30915 @subsection Hurd Services
30917 @defvr {Scheme Variable} hurd-console-service-type
30918 This service starts the fancy @code{VGA} console client on the Hurd.
30920 The service's value is a @code{hurd-console-configuration} record.
30923 @deftp {Data Type} hurd-console-configuration
30924 This is the data type representing the configuration for the
30925 hurd-console-service.
30928 @item @code{hurd} (default: @var{hurd})
30929 The Hurd package to use.
30933 @defvr {Scheme Variable} hurd-getty-service-type
30934 This service starts a tty using the Hurd @code{getty} program.
30936 The service's value is a @code{hurd-getty-configuration} record.
30939 @deftp {Data Type} hurd-getty-configuration
30940 This is the data type representing the configuration for the
30941 hurd-getty-service.
30944 @item @code{hurd} (default: @var{hurd})
30945 The Hurd package to use.
30948 The name of the console this Getty runs on---e.g., @code{"tty1"}.
30950 @item @code{baud-rate} (default: @code{38400})
30951 An integer specifying the baud rate of the tty.
30956 @node Miscellaneous Services
30957 @subsection Miscellaneous Services
30959 @cindex fingerprint
30960 @subsubheading Fingerprint Service
30962 The @code{(gnu services authentication)} module provides a DBus service to
30963 read and identify fingerprints via a fingerprint sensor.
30965 @defvr {Scheme Variable} fprintd-service-type
30966 The service type for @command{fprintd}, which provides the fingerprint
30967 reading capability.
30970 (service fprintd-service-type)
30975 @subsubheading System Control Service
30977 The @code{(gnu services sysctl)} provides a service to configure kernel
30978 parameters at boot.
30980 @defvr {Scheme Variable} sysctl-service-type
30981 The service type for @command{sysctl}, which modifies kernel parameters
30982 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
30986 (service sysctl-service-type
30987 (sysctl-configuration
30988 (settings '(("net.ipv4.ip_forward" . "1")))))
30992 @deftp {Data Type} sysctl-configuration
30993 The data type representing the configuration of @command{sysctl}.
30996 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
30997 The @command{sysctl} executable to use.
30999 @item @code{settings} (default: @code{'()})
31000 An association list specifies kernel parameters and their values.
31005 @subsubheading PC/SC Smart Card Daemon Service
31007 The @code{(gnu services security-token)} module provides the following service
31008 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
31009 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
31010 manager that coordinates communications with smart card readers, smart cards
31011 and cryptographic tokens that are connected to the system.
31013 @defvr {Scheme Variable} pcscd-service-type
31014 Service type for the @command{pcscd} service. Its value must be a
31015 @code{pcscd-configuration} object. To run pcscd in the default
31016 configuration, instantiate it as:
31019 (service pcscd-service-type)
31023 @deftp {Data Type} pcscd-configuration
31024 The data type representing the configuration of @command{pcscd}.
31027 @item @code{pcsc-lite} (default: @code{pcsc-lite})
31028 The pcsc-lite package that provides pcscd.
31029 @item @code{usb-drivers} (default: @code{(list ccid)})
31030 List of packages that provide USB drivers to pcscd. Drivers are expected to be
31031 under @file{pcsc/drivers} in the store directory of the package.
31036 @subsubheading Lirc Service
31038 The @code{(gnu services lirc)} module provides the following service.
31040 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
31041 [#:device #f] [#:driver #f] [#:config-file #f] @
31042 [#:extra-options '()]
31043 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
31044 decodes infrared signals from remote controls.
31046 Optionally, @var{device}, @var{driver} and @var{config-file}
31047 (configuration file name) may be specified. See @command{lircd} manual
31050 Finally, @var{extra-options} is a list of additional command-line options
31051 passed to @command{lircd}.
31055 @subsubheading Spice Service
31057 The @code{(gnu services spice)} module provides the following service.
31059 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
31060 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
31061 that enables sharing the clipboard with a vm and setting the guest display
31062 resolution when the graphical console window resizes.
31065 @cindex inputattach
31066 @subsubheading inputattach Service
31068 @cindex tablet input, for Xorg
31069 @cindex touchscreen input, for Xorg
31070 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
31071 use input devices such as Wacom tablets, touchscreens, or joysticks with the
31072 Xorg display server.
31074 @deffn {Scheme Variable} inputattach-service-type
31075 Type of a service that runs @command{inputattach} on a device and
31076 dispatches events from it.
31079 @deftp {Data Type} inputattach-configuration
31081 @item @code{device-type} (default: @code{"wacom"})
31082 The type of device to connect to. Run @command{inputattach --help}, from the
31083 @code{inputattach} package, to see the list of supported device types.
31085 @item @code{device} (default: @code{"/dev/ttyS0"})
31086 The device file to connect to the device.
31088 @item @code{baud-rate} (default: @code{#f})
31089 Baud rate to use for the serial connection.
31090 Should be a number or @code{#f}.
31092 @item @code{log-file} (default: @code{#f})
31093 If true, this must be the name of a file to log messages to.
31097 @subsubheading Dictionary Service
31099 The @code{(gnu services dict)} module provides the following service:
31101 @defvr {Scheme Variable} dicod-service-type
31102 This is the type of the service that runs the @command{dicod} daemon, an
31103 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
31106 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
31107 Return a service that runs the @command{dicod} daemon, an implementation
31108 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
31110 The optional @var{config} argument specifies the configuration for
31111 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
31112 default it serves the GNU Collaborative International Dictionary of English.
31114 You can add @command{open localhost} to your @file{~/.dico} file to make
31115 @code{localhost} the default server for @command{dico} client
31116 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
31119 @deftp {Data Type} dicod-configuration
31120 Data type representing the configuration of dicod.
31123 @item @code{dico} (default: @var{dico})
31124 Package object of the GNU Dico dictionary server.
31126 @item @code{interfaces} (default: @var{'("localhost")})
31127 This is the list of IP addresses and ports and possibly socket file
31128 names to listen to (@pxref{Server Settings, @code{listen} directive,,
31129 dico, GNU Dico Manual}).
31131 @item @code{handlers} (default: @var{'()})
31132 List of @code{<dicod-handler>} objects denoting handlers (module instances).
31134 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
31135 List of @code{<dicod-database>} objects denoting dictionaries to be served.
31139 @deftp {Data Type} dicod-handler
31140 Data type representing a dictionary handler (module instance).
31144 Name of the handler (module instance).
31146 @item @code{module} (default: @var{#f})
31147 Name of the dicod module of the handler (instance). If it is @code{#f},
31148 the module has the same name as the handler.
31149 (@pxref{Modules,,, dico, GNU Dico Manual}).
31151 @item @code{options}
31152 List of strings or gexps representing the arguments for the module handler
31156 @deftp {Data Type} dicod-database
31157 Data type representing a dictionary database.
31161 Name of the database, will be used in DICT commands.
31163 @item @code{handler}
31164 Name of the dicod handler (module instance) used by this database
31165 (@pxref{Handlers,,, dico, GNU Dico Manual}).
31167 @item @code{complex?} (default: @var{#f})
31168 Whether the database configuration complex. The complex configuration
31169 will need a corresponding @code{<dicod-handler>} object, otherwise not.
31171 @item @code{options}
31172 List of strings or gexps representing the arguments for the database
31173 (@pxref{Databases,,, dico, GNU Dico Manual}).
31177 @defvr {Scheme Variable} %dicod-database:gcide
31178 A @code{<dicod-database>} object serving the GNU Collaborative International
31179 Dictionary of English using the @code{gcide} package.
31182 The following is an example @code{dicod-service} configuration.
31185 (dicod-service #:config
31186 (dicod-configuration
31187 (handlers (list (dicod-handler
31191 (list #~(string-append "dbdir=" #$wordnet))))))
31192 (databases (list (dicod-database
31195 (handler "wordnet")
31196 (options '("database=wn")))
31197 %dicod-database:gcide))))
31201 @subsubheading Docker Service
31203 The @code{(gnu services docker)} module provides the following services.
31205 @defvr {Scheme Variable} docker-service-type
31207 This is the type of the service that runs @url{https://www.docker.com,Docker},
31208 a daemon that can execute application bundles (sometimes referred to as
31209 ``containers'') in isolated environments.
31213 @deftp {Data Type} docker-configuration
31214 This is the data type representing the configuration of Docker and Containerd.
31218 @item @code{package} (default: @code{docker})
31219 The Docker daemon package to use.
31221 @item @code{package} (default: @code{docker-cli})
31222 The Docker client package to use.
31224 @item @code{containerd} (default: @var{containerd})
31225 The Containerd package to use.
31227 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
31228 The Docker user-land networking proxy package to use.
31230 @item @code{enable-proxy?} (default @code{#t})
31231 Enable or disable the use of the Docker user-land networking proxy.
31233 @item @code{debug?} (default @code{#f})
31234 Enable or disable debug output.
31236 @item @code{enable-iptables?} (default @code{#t})
31237 Enable or disable the addition of iptables rules.
31242 @cindex Singularity, container service
31243 @defvr {Scheme Variable} singularity-service-type
31244 This is the type of the service that allows you to run
31245 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
31246 create and run application bundles (aka. ``containers''). The value for this
31247 service is the Singularity package to use.
31249 The service does not install a daemon; instead, it installs helper programs as
31250 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
31251 @command{singularity run} and similar commands.
31255 @subsubheading Auditd Service
31257 The @code{(gnu services auditd)} module provides the following service.
31259 @defvr {Scheme Variable} auditd-service-type
31261 This is the type of the service that runs
31262 @url{https://people.redhat.com/sgrubb/audit/,auditd},
31263 a daemon that tracks security-relevant information on your system.
31265 Examples of things that can be tracked:
31275 Failed login attempts
31282 @command{auditctl} from the @code{audit} package can be used in order
31283 to add or remove events to be tracked (until the next reboot).
31284 In order to permanently track events, put the command line arguments
31285 of auditctl into a file called @code{audit.rules} in the configuration
31286 directory (see below).
31287 @command{aureport} from the @code{audit} package can be used in order
31288 to view a report of all recorded events.
31289 The audit daemon by default logs into the file
31290 @file{/var/log/audit.log}.
31294 @deftp {Data Type} auditd-configuration
31295 This is the data type representing the configuration of auditd.
31299 @item @code{audit} (default: @code{audit})
31300 The audit package to use.
31302 @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
31303 The directory containing the configuration file for the audit package, which
31304 must be named @code{auditd.conf}, and optionally some audit rules to
31305 instantiate on startup.
31311 @subsubheading R-Shiny service
31313 The @code{(gnu services science)} module provides the following service.
31315 @defvr {Scheme Variable} rshiny-service-type
31317 This is a type of service which is used to run a webapp created with
31318 @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
31319 variable and runs the provided script to call @code{runApp}.
31321 @deftp {Data Type} rshiny-configuration
31322 This is the data type representing the configuration of rshiny.
31326 @item @code{package} (default: @code{r-shiny})
31327 The package to use.
31329 @item @code{binary} (defaunlt @code{"rshiny"})
31330 The name of the binary or shell script located at @code{package/bin/} to
31331 run when the service is run.
31333 The common way to create this file is as follows:
31337 (let* ((out (assoc-ref %outputs "out"))
31338 (targetdir (string-append out "/share/" ,name))
31339 (app (string-append out "/bin/" ,name))
31340 (Rbin (string-append (assoc-ref %build-inputs "r-min")
31343 (mkdir-p (string-append out "/bin"))
31344 (call-with-output-file app
31350 runApp(launch.browser=0, port=4202)~%\n"
31359 @subsubheading Nix service
31361 The @code{(gnu services nix)} module provides the following service.
31363 @defvr {Scheme Variable} nix-service-type
31365 This is the type of the service that runs build daemon of the
31366 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
31370 (use-modules (gnu))
31371 (use-service-modules nix)
31372 (use-package-modules package-management)
31376 (packages (append (list nix)
31379 (services (append (list (service nix-service-type))
31383 After @command{guix system reconfigure} configure Nix for your user:
31386 @item Add a Nix channel and update it. See
31387 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
31389 @item Create a symlink to your profile and activate Nix profile:
31393 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
31394 $ source /run/current-system/profile/etc/profile.d/nix.sh
31399 @deftp {Data Type} nix-configuration
31400 This data type represents the configuration of the Nix daemon.
31403 @item @code{nix} (default: @code{nix})
31404 The Nix package to use.
31406 @item @code{sandbox} (default: @code{#t})
31407 Specifies whether builds are sandboxed by default.
31409 @item @code{build-sandbox-items} (default: @code{'()})
31410 This is a list of strings or objects appended to the
31411 @code{build-sandbox-items} field of the configuration file.
31413 @item @code{extra-config} (default: @code{'()})
31414 This is a list of strings or objects appended to the configuration file.
31415 It is used to pass extra text to be added verbatim to the configuration
31418 @item @code{extra-options} (default: @code{'()})
31419 Extra command line options for @code{nix-service-type}.
31423 @node Setuid Programs
31424 @section Setuid Programs
31426 @cindex setuid programs
31427 Some programs need to run with ``root'' privileges, even when they are
31428 launched by unprivileged users. A notorious example is the
31429 @command{passwd} program, which users can run to change their
31430 password, and which needs to access the @file{/etc/passwd} and
31431 @file{/etc/shadow} files---something normally restricted to root, for
31432 obvious security reasons. To address that, these executables are
31433 @dfn{setuid-root}, meaning that they always run with root privileges
31434 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
31435 for more info about the setuid mechanism).
31437 The store itself @emph{cannot} contain setuid programs: that would be a
31438 security issue since any user on the system can write derivations that
31439 populate the store (@pxref{The Store}). Thus, a different mechanism is
31440 used: instead of changing the setuid bit directly on files that are in
31441 the store, we let the system administrator @emph{declare} which programs
31442 should be setuid root.
31444 The @code{setuid-programs} field of an @code{operating-system}
31445 declaration contains a list of G-expressions denoting the names of
31446 programs to be setuid-root (@pxref{Using the Configuration System}).
31447 For instance, the @command{passwd} program, which is part of the Shadow
31448 package, can be designated by this G-expression (@pxref{G-Expressions}):
31451 #~(string-append #$shadow "/bin/passwd")
31454 A default set of setuid programs is defined by the
31455 @code{%setuid-programs} variable of the @code{(gnu system)} module.
31457 @defvr {Scheme Variable} %setuid-programs
31458 A list of G-expressions denoting common programs that are setuid-root.
31460 The list includes commands such as @command{passwd}, @command{ping},
31461 @command{su}, and @command{sudo}.
31464 Under the hood, the actual setuid programs are created in the
31465 @file{/run/setuid-programs} directory at system activation time. The
31466 files in this directory refer to the ``real'' binaries, which are in the
31469 @node X.509 Certificates
31470 @section X.509 Certificates
31472 @cindex HTTPS, certificates
31473 @cindex X.509 certificates
31475 Web servers available over HTTPS (that is, HTTP over the transport-layer
31476 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
31477 that the client can then use to @emph{authenticate} the server. To do
31478 that, clients verify that the server's certificate is signed by a
31479 so-called @dfn{certificate authority} (CA). But to verify the CA's
31480 signature, clients must have first acquired the CA's certificate.
31482 Web browsers such as GNU@tie{}IceCat include their own set of CA
31483 certificates, such that they are able to verify CA signatures
31486 However, most other programs that can talk HTTPS---@command{wget},
31487 @command{git}, @command{w3m}, etc.---need to be told where CA
31488 certificates can be found.
31490 @cindex @code{nss-certs}
31491 In Guix, this is done by adding a package that provides certificates
31492 to the @code{packages} field of the @code{operating-system} declaration
31493 (@pxref{operating-system Reference}). Guix includes one such package,
31494 @code{nss-certs}, which is a set of CA certificates provided as part of
31495 Mozilla's Network Security Services.
31497 Note that it is @emph{not} part of @code{%base-packages}, so you need to
31498 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
31499 most applications and libraries look for certificates by default, points
31500 to the certificates installed globally.
31502 Unprivileged users, including users of Guix on a foreign distro,
31503 can also install their own certificate package in
31504 their profile. A number of environment variables need to be defined so
31505 that applications and libraries know where to find them. Namely, the
31506 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
31507 variables. Some applications add their own environment variables; for
31508 instance, the Git version control system honors the certificate bundle
31509 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
31510 would typically run something like:
31513 guix install nss-certs
31514 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
31515 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
31516 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
31519 As another example, R requires the @env{CURL_CA_BUNDLE} environment
31520 variable to point to a certificate bundle, so you would have to run
31521 something like this:
31524 guix install nss-certs
31525 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
31528 For other applications you may want to look up the required environment
31529 variable in the relevant documentation.
31532 @node Name Service Switch
31533 @section Name Service Switch
31535 @cindex name service switch
31537 The @code{(gnu system nss)} module provides bindings to the
31538 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
31539 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
31540 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
31541 extended with new ``name'' lookup methods for system databases, which
31542 includes host names, service names, user accounts, and more (@pxref{Name
31543 Service Switch, System Databases and Name Service Switch,, libc, The GNU
31544 C Library Reference Manual}).
31546 The NSS configuration specifies, for each system database, which lookup
31547 method is to be used, and how the various methods are chained
31548 together---for instance, under which circumstances NSS should try the
31549 next method in the list. The NSS configuration is given in the
31550 @code{name-service-switch} field of @code{operating-system} declarations
31551 (@pxref{operating-system Reference, @code{name-service-switch}}).
31554 @cindex .local, host name lookup
31555 As an example, the declaration below configures the NSS to use the
31556 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
31557 back-end}, which supports host name lookups over multicast DNS (mDNS)
31558 for host names ending in @code{.local}:
31561 (name-service-switch
31562 (hosts (list %files ;first, check /etc/hosts
31564 ;; If the above did not succeed, try
31565 ;; with 'mdns_minimal'.
31567 (name "mdns_minimal")
31569 ;; 'mdns_minimal' is authoritative for
31570 ;; '.local'. When it returns "not found",
31571 ;; no need to try the next methods.
31572 (reaction (lookup-specification
31573 (not-found => return))))
31575 ;; Then fall back to DNS.
31579 ;; Finally, try with the "full" 'mdns'.
31584 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
31585 contains this configuration, so you will not have to type it if all you
31586 want is to have @code{.local} host lookup working.
31588 Note that, in this case, in addition to setting the
31589 @code{name-service-switch} of the @code{operating-system} declaration,
31590 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
31591 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
31592 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
31593 to the name service cache daemon (@pxref{Base Services,
31594 @code{nscd-service}}).
31596 For convenience, the following variables provide typical NSS
31599 @defvr {Scheme Variable} %default-nss
31600 This is the default name service switch configuration, a
31601 @code{name-service-switch} object.
31604 @defvr {Scheme Variable} %mdns-host-lookup-nss
31605 This is the name service switch configuration with support for host name
31606 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
31609 The reference for name service switch configuration is given below. It
31610 is a direct mapping of the configuration file format of the C library , so
31611 please refer to the C library manual for more information (@pxref{NSS
31612 Configuration File,,, libc, The GNU C Library Reference Manual}).
31613 Compared to the configuration file format of libc NSS, it has the advantage
31614 not only of adding this warm parenthetic feel that we like, but also
31615 static checks: you will know about syntax errors and typos as soon as you
31616 run @command{guix system}.
31618 @deftp {Data Type} name-service-switch
31620 This is the data type representation the configuration of libc's name
31621 service switch (NSS). Each field below represents one of the supported
31638 The system databases handled by the NSS@. Each of these fields must be a
31639 list of @code{<name-service>} objects (see below).
31643 @deftp {Data Type} name-service
31645 This is the data type representing an actual name service and the
31646 associated lookup action.
31650 A string denoting the name service (@pxref{Services in the NSS
31651 configuration,,, libc, The GNU C Library Reference Manual}).
31653 Note that name services listed here must be visible to nscd. This is
31654 achieved by passing the @code{#:name-services} argument to
31655 @code{nscd-service} the list of packages providing the needed name
31656 services (@pxref{Base Services, @code{nscd-service}}).
31659 An action specified using the @code{lookup-specification} macro
31660 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
31661 Reference Manual}). For example:
31664 (lookup-specification (unavailable => continue)
31665 (success => return))
31670 @node Initial RAM Disk
31671 @section Initial RAM Disk
31674 @cindex initial RAM disk
31675 For bootstrapping purposes, the Linux-Libre kernel is passed an
31676 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
31677 root file system as well as an initialization script. The latter is
31678 responsible for mounting the real root file system, and for loading any
31679 kernel modules that may be needed to achieve that.
31681 The @code{initrd-modules} field of an @code{operating-system}
31682 declaration allows you to specify Linux-libre kernel modules that must
31683 be available in the initrd. In particular, this is where you would list
31684 modules needed to actually drive the hard disk where your root partition
31685 is---although the default value of @code{initrd-modules} should cover
31686 most use cases. For example, assuming you need the @code{megaraid_sas}
31687 module in addition to the default modules to be able to access your root
31688 file system, you would write:
31693 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
31696 @defvr {Scheme Variable} %base-initrd-modules
31697 This is the list of kernel modules included in the initrd by default.
31700 Furthermore, if you need lower-level customization, the @code{initrd}
31701 field of an @code{operating-system} declaration allows
31702 you to specify which initrd you would like to use. The @code{(gnu
31703 system linux-initrd)} module provides three ways to build an initrd: the
31704 high-level @code{base-initrd} procedure and the low-level
31705 @code{raw-initrd} and @code{expression->initrd} procedures.
31707 The @code{base-initrd} procedure is intended to cover most common uses.
31708 For example, if you want to add a bunch of kernel modules to be loaded
31709 at boot time, you can define the @code{initrd} field of the operating
31710 system declaration like this:
31713 (initrd (lambda (file-systems . rest)
31714 ;; Create a standard initrd but set up networking
31715 ;; with the parameters QEMU expects by default.
31716 (apply base-initrd file-systems
31717 #:qemu-networking? #t
31721 The @code{base-initrd} procedure also handles common use cases that
31722 involves using the system as a QEMU guest, or as a ``live'' system with
31723 volatile root file system.
31725 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
31726 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
31727 such as trying to guess which kernel modules and packages should be included
31728 to the initrd. An example use of @code{raw-initrd} is when a user has
31729 a custom Linux kernel configuration and default kernel modules included by
31730 @code{base-initrd} are not available.
31732 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
31733 honors several options passed on the Linux kernel command line
31734 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
31735 @code{-append} option of QEMU), notably:
31738 @item --load=@var{boot}
31739 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
31740 program, once it has mounted the root file system.
31742 Guix uses this option to yield control to a boot program that runs the
31743 service activation programs and then spawns the GNU@tie{}Shepherd, the
31744 initialization system.
31746 @item --root=@var{root}
31747 Mount @var{root} as the root file system. @var{root} can be a device
31748 name like @code{/dev/sda1}, a file system label, or a file system UUID.
31749 When unspecified, the device name from the root file system of the
31750 operating system declaration is used.
31752 @item --system=@var{system}
31753 Have @file{/run/booted-system} and @file{/run/current-system} point to
31756 @item modprobe.blacklist=@var{modules}@dots{}
31757 @cindex module, black-listing
31758 @cindex black list, of kernel modules
31759 Instruct the initial RAM disk as well as the @command{modprobe} command
31760 (from the kmod package) to refuse to load @var{modules}. @var{modules}
31761 must be a comma-separated list of module names---e.g.,
31762 @code{usbkbd,9pnet}.
31765 Start a read-eval-print loop (REPL) from the initial RAM disk before it
31766 tries to load kernel modules and to mount the root file system. Our
31767 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
31768 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
31769 Manual}, for more information on Guile's REPL.
31773 Now that you know all the features that initial RAM disks produced by
31774 @code{base-initrd} and @code{raw-initrd} provide,
31775 here is how to use it and customize it further.
31778 @cindex initial RAM disk
31779 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
31780 [#:linux-modules '()] [#:mapped-devices '()] @
31781 [#:keyboard-layout #f] @
31782 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
31783 Return a derivation that builds a raw initrd. @var{file-systems} is
31784 a list of file systems to be mounted by the initrd, possibly in addition to
31785 the root file system specified on the kernel command line via @option{--root}.
31786 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
31787 @var{mapped-devices} is a list of device mappings to realize before
31788 @var{file-systems} are mounted (@pxref{Mapped Devices}).
31789 @var{helper-packages} is a list of packages to be copied in the initrd.
31791 include @code{e2fsck/static} or other packages needed by the initrd to check
31792 the root file system.
31794 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
31795 the desired console keyboard layout. This is done before @var{mapped-devices}
31796 are set up and before @var{file-systems} are mounted such that, should the
31797 user need to enter a passphrase or use the REPL, this happens using the
31798 intended keyboard layout.
31800 When @var{qemu-networking?} is true, set up networking with the standard QEMU
31801 parameters. When @var{virtio?} is true, load additional modules so that the
31802 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
31804 When @var{volatile-root?} is true, the root file system is writable but any changes
31808 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
31809 [#:mapped-devices '()] [#:keyboard-layout #f] @
31810 [#:qemu-networking? #f] [#:volatile-root? #f] @
31811 [#:linux-modules '()]
31812 Return as a file-like object a generic initrd, with kernel
31813 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
31814 mounted by the initrd, possibly in addition to the root file system specified
31815 on the kernel command line via @option{--root}. @var{mapped-devices} is a list of device
31816 mappings to realize before @var{file-systems} are mounted.
31818 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
31819 the desired console keyboard layout. This is done before @var{mapped-devices}
31820 are set up and before @var{file-systems} are mounted such that, should the
31821 user need to enter a passphrase or use the REPL, this happens using the
31822 intended keyboard layout.
31824 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
31826 The initrd is automatically populated with all the kernel modules necessary
31827 for @var{file-systems} and for the given options. Additional kernel
31828 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
31829 loaded at boot time in the order in which they appear.
31832 Needless to say, the initrds we produce and use embed a
31833 statically-linked Guile, and the initialization program is a Guile
31834 program. That gives a lot of flexibility. The
31835 @code{expression->initrd} procedure builds such an initrd, given the
31836 program to run in that initrd.
31838 @deffn {Scheme Procedure} expression->initrd @var{exp} @
31839 [#:guile %guile-3.0-static-stripped] [#:name "guile-initrd"]
31840 Return as a file-like object a Linux initrd (a gzipped cpio archive)
31841 containing @var{guile} and that evaluates @var{exp}, a G-expression,
31842 upon booting. All the derivations referenced by @var{exp} are
31843 automatically copied to the initrd.
31846 @node Bootloader Configuration
31847 @section Bootloader Configuration
31850 @cindex boot loader
31852 The operating system supports multiple bootloaders. The bootloader is
31853 configured using @code{bootloader-configuration} declaration. All the
31854 fields of this structure are bootloader agnostic except for one field,
31855 @code{bootloader} that indicates the bootloader to be configured and
31858 Some of the bootloaders do not honor every field of
31859 @code{bootloader-configuration}. For instance, the extlinux
31860 bootloader does not support themes and thus ignores the @code{theme}
31863 @deftp {Data Type} bootloader-configuration
31864 The type of a bootloader configuration declaration.
31868 @item @code{bootloader}
31869 @cindex EFI, bootloader
31870 @cindex UEFI, bootloader
31871 @cindex BIOS, bootloader
31872 The bootloader to use, as a @code{bootloader} object. For now
31873 @code{grub-bootloader}, @code{grub-efi-bootloader},
31874 @code{grub-efi-netboot-bootloader}, @code{extlinux-bootloader} and
31875 @code{u-boot-bootloader} are supported.
31877 @cindex ARM, bootloaders
31878 @cindex AArch64, bootloaders
31879 Available bootloaders are described in @code{(gnu bootloader @dots{})}
31880 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
31881 of bootloaders for a wide range of ARM and AArch64 systems, using the
31882 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
31884 @vindex grub-efi-bootloader
31885 @code{grub-efi-bootloader} allows to boot on modern systems using the
31886 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
31887 use if the installation image contains a @file{/sys/firmware/efi} directory
31888 when you boot it on your system.
31890 @vindex grub-bootloader
31891 @code{grub-bootloader} allows you to boot in particular Intel-based machines
31892 in ``legacy'' BIOS mode.
31894 @vindex grub-efi-netboot-bootloader
31895 @code{grub-efi-netboot-bootloader} allows you to boot your system over network
31896 through TFTP@. In combination with an NFS root file system this allows you to
31897 build a diskless Guix system.
31899 The installation of the @code{grub-efi-netboot-bootloader} generates the content
31900 of the TFTP root directory at @code{target}
31901 (@pxref{Bootloader Configuration, @code{target}}), to be served by a TFTP server.
31902 You may want to mount your TFTP server directory onto @code{target} to move the
31903 required files to the TFTP server automatically.
31905 If you plan to use an NFS root file system as well (actually if you mount the
31906 store from an NFS share), then the TFTP server needs to serve the file
31907 @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
31908 image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
31909 initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
31910 files from the store will be accessed by GRUB through TFTP with their normal
31911 store path, for example as
31912 @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
31914 Two symlinks are created to make this possible. The first symlink is
31915 @code{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
31916 @file{../../../boot/grub/grub.cfg},
31917 where @code{target} may be @file{/boot}. In this case the link is not leaving
31918 the served TFTP root directory, but otherwise it does. The second link is
31919 @code{target}@file{/gnu/store} and points to @file{../gnu/store}. This link
31920 is leaving the served TFTP root directory.
31922 The assumption behind all this is that you have an NFS server exporting the root
31923 file system for your Guix system, and additionally a TFTP server exporting your
31924 @code{target} directory—usually @file{/boot}—from that same root file system for
31925 your Guix system. In this constellation the symlinks will work.
31927 For other constellations you will have to program your own bootloader installer,
31928 which then takes care to make necessary files from the store accessible through
31929 TFTP, for example by copying them into the TFTP root directory at @code{target}.
31931 It is important to note that symlinks pointing outside the TFTP root directory
31932 may need to be allowed in the configuration of your TFTP server. Further the
31933 store link exposes the whole store through TFTP@. Both points need to be
31934 considered carefully for security aspects.
31936 Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
31937 NFS servers, you also need a properly configured DHCP server to make the booting
31938 over netboot possible. For all this we can currently only recommend you to look
31939 for instructions about @acronym{PXE, Preboot eXecution Environment}.
31941 @item @code{target}
31942 This is a string denoting the target onto which to install the
31945 The interpretation depends on the bootloader in question. For
31946 @code{grub-bootloader}, for example, it should be a device name understood by
31947 the bootloader @command{installer} command, such as @code{/dev/sda} or
31948 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
31949 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
31950 system, usually @file{/boot/efi}. For @code{grub-efi-netboot-bootloader},
31951 @code{target} should be the mount point corresponding to the TFTP root
31952 directory of your TFTP server.
31954 @item @code{menu-entries} (default: @code{()})
31955 A possibly empty list of @code{menu-entry} objects (see below), denoting
31956 entries to appear in the bootloader menu, in addition to the current
31957 system entry and the entry pointing to previous system generations.
31959 @item @code{default-entry} (default: @code{0})
31960 The index of the default boot menu entry. Index 0 is for the entry of the
31963 @item @code{timeout} (default: @code{5})
31964 The number of seconds to wait for keyboard input before booting. Set to
31965 0 to boot immediately, and to -1 to wait indefinitely.
31967 @cindex keyboard layout, for the bootloader
31968 @item @code{keyboard-layout} (default: @code{#f})
31969 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
31970 layout, usually US@tie{}English (``qwerty'').
31972 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
31976 This option is currently ignored by bootloaders other than @code{grub} and
31980 @item @code{theme} (default: @var{#f})
31981 The bootloader theme object describing the theme to use. If no theme
31982 is provided, some bootloaders might use a default theme, that's true
31985 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
31986 The output terminals used for the bootloader boot menu, as a list of
31987 symbols. GRUB accepts the values: @code{console}, @code{serial},
31988 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
31989 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
31990 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
31991 configuration,,, grub,GNU GRUB manual}).
31993 @item @code{terminal-inputs} (default: @code{'()})
31994 The input terminals used for the bootloader boot menu, as a list of
31995 symbols. For GRUB, the default is the native platform terminal as
31996 determined at run-time. GRUB accepts the values: @code{console},
31997 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
31998 @code{usb_keyboard}. This field corresponds to the GRUB variable
31999 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
32002 @item @code{serial-unit} (default: @code{#f})
32003 The serial unit used by the bootloader, as an integer from 0 to 3.
32004 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
32005 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
32007 @item @code{serial-speed} (default: @code{#f})
32008 The speed of the serial interface, as an integer. For GRUB, the
32009 default value is chosen at run-time; currently GRUB chooses
32010 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
32017 Should you want to list additional boot menu entries @i{via} the
32018 @code{menu-entries} field above, you will need to create them with the
32019 @code{menu-entry} form. For example, imagine you want to be able to
32020 boot another distro (hard to imagine!), you can define a menu entry
32025 (label "The Other Distro")
32026 (linux "/boot/old/vmlinux-2.6.32")
32027 (linux-arguments '("root=/dev/sda2"))
32028 (initrd "/boot/old/initrd"))
32033 @deftp {Data Type} menu-entry
32034 The type of an entry in the bootloader menu.
32039 The label to show in the menu---e.g., @code{"GNU"}.
32041 @item @code{linux} (default: @code{#f})
32042 The Linux kernel image to boot, for example:
32045 (file-append linux-libre "/bzImage")
32048 For GRUB, it is also possible to specify a device explicitly in the
32049 file path using GRUB's device naming convention (@pxref{Naming
32050 convention,,, grub, GNU GRUB manual}), for example:
32053 "(hd0,msdos1)/boot/vmlinuz"
32056 If the device is specified explicitly as above, then the @code{device}
32057 field is ignored entirely.
32059 @item @code{linux-arguments} (default: @code{()})
32060 The list of extra Linux kernel command-line arguments---e.g.,
32061 @code{("console=ttyS0")}.
32063 @item @code{initrd} (default: @code{#f})
32064 A G-Expression or string denoting the file name of the initial RAM disk
32065 to use (@pxref{G-Expressions}).
32067 @item @code{device} (default: @code{#f})
32068 The device where the kernel and initrd are to be found---i.e., for GRUB,
32069 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
32071 This may be a file system label (a string), a file system UUID (a
32072 bytevector, @pxref{File Systems}), or @code{#f}, in which case
32073 the bootloader will search the device containing the file specified by
32074 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
32075 must @emph{not} be an OS device name such as @file{/dev/sda1}.
32077 @item @code{multiboot-kernel} (default: @code{#f})
32078 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
32079 manual}). When this field is set, a Multiboot menu-entry is generated.
32083 (file-append mach "/boot/gnumach")
32086 @item @code{multiboot-arguments} (default: @code{()})
32087 The list of extra command-line arguments for the multiboot-kernel.
32089 @item @code{multiboot-modules} (default: @code{()})
32090 The list of commands for loading Multiboot modules. For example:
32093 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
32095 (list (file-append libc "/lib/ld.so.1") "exec"
32105 @c FIXME: Write documentation once it's stable.
32106 For now only GRUB has theme support. GRUB themes are created using
32107 the @code{grub-theme} form, which is not fully documented yet.
32109 @deftp {Data Type} grub-theme
32110 Data type representing the configuration of the GRUB theme.
32113 @item @code{gfxmode} (default: @code{'("auto")})
32114 The GRUB @code{gfxmode} to set (a list of screen resolution strings,
32115 @pxref{gfxmode,,, grub, GNU GRUB manual}).
32119 @deffn {Scheme Procedure} grub-theme
32120 Return the default GRUB theme used by the operating system if no
32121 @code{theme} field is specified in @code{bootloader-configuration}
32124 It comes with a fancy background image displaying the GNU and Guix
32128 For example, to override the default resolution, you may use something
32133 (bootloader-configuration
32136 (inherit (grub-theme))
32137 (gfxmode '("1024x786x32" "auto"))))))
32140 @node Invoking guix system
32141 @section Invoking @code{guix system}
32143 Once you have written an operating system declaration as seen in the
32144 previous section, it can be @dfn{instantiated} using the @command{guix
32145 system} command. The synopsis is:
32148 guix system @var{options}@dots{} @var{action} @var{file}
32151 @var{file} must be the name of a file containing an
32152 @code{operating-system} declaration. @var{action} specifies how the
32153 operating system is instantiated. Currently the following values are
32158 Display available service type definitions that match the given regular
32159 expressions, sorted by relevance:
32165 $ guix system search console
32166 name: console-fonts
32167 location: gnu/services/base.scm:806:2
32168 extends: shepherd-root
32169 description: Install the given fonts on the specified ttys (fonts are per
32170 + virtual console on GNU/Linux). The value of this service is a list of
32171 + tty/font pairs. The font can be the name of a font provided by the `kbd'
32172 + package or any valid argument to `setfont', as in this example:
32174 + '(("tty1" . "LatGrkCyr-8x16")
32175 + ("tty2" . (file-append
32177 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
32178 + ("tty3" . (file-append
32180 + "/share/consolefonts/ter-132n"))) ; for HDPI
32184 location: gnu/services/base.scm:1190:2
32185 extends: shepherd-root
32186 description: Provide console login using the `mingetty' program.
32190 location: gnu/services/base.scm:860:2
32192 description: Provide a console log-in service as specified by its
32193 + configuration value, a `login-configuration' object.
32199 As for @command{guix package --search}, the result is written in
32200 @code{recutils} format, which makes it easy to filter the output
32201 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
32204 Build the operating system described in @var{file}, activate it, and
32205 switch to it@footnote{This action (and the related actions
32206 @code{switch-generation} and @code{roll-back}) are usable only on
32207 systems already running Guix System.}.
32210 @c The paragraph below refers to the problem discussed at
32211 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
32212 It is highly recommended to run @command{guix pull} once before you run
32213 @command{guix system reconfigure} for the first time (@pxref{Invoking
32214 guix pull}). Failing to do that you would see an older version of Guix
32215 once @command{reconfigure} has completed.
32218 This effects all the configuration specified in @var{file}: user
32219 accounts, system services, global package list, setuid programs, etc.
32220 The command starts system services specified in @var{file} that are not
32221 currently running; if a service is currently running this command will
32222 arrange for it to be upgraded the next time it is stopped (e.g.@: by
32223 @code{herd stop X} or @code{herd restart X}).
32225 This command creates a new generation whose number is one greater than
32226 the current generation (as reported by @command{guix system
32227 list-generations}). If that generation already exists, it will be
32228 overwritten. This behavior mirrors that of @command{guix package}
32229 (@pxref{Invoking guix package}).
32231 It also adds a bootloader menu entry for the new OS configuration,
32232 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
32233 entries for older configurations to a submenu, allowing you to choose
32234 an older system generation at boot time should you need it.
32236 @cindex provenance tracking, of the operating system
32237 Upon completion, the new system is deployed under
32238 @file{/run/current-system}. This directory contains @dfn{provenance
32239 meta-data}: the list of channels in use (@pxref{Channels}) and
32240 @var{file} itself, when available. You can view it by running:
32243 guix system describe
32246 This information is useful should you later want to inspect how this
32247 particular generation was built. In fact, assuming @var{file} is
32248 self-contained, you can later rebuild generation @var{n} of your
32249 operating system with:
32252 guix time-machine \
32253 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
32254 system reconfigure \
32255 /var/guix/profiles/system-@var{n}-link/configuration.scm
32258 You can think of it as some sort of built-in version control! Your
32259 system is not just a binary artifact: @emph{it carries its own source}.
32260 @xref{Service Reference, @code{provenance-service-type}}, for more
32261 information on provenance tracking.
32263 By default, @command{reconfigure} @emph{prevents you from downgrading
32264 your system}, which could (re)introduce security vulnerabilities and
32265 also cause problems with ``stateful'' services such as database
32266 management systems. You can override that behavior by passing
32267 @option{--allow-downgrades}.
32269 @item switch-generation
32270 @cindex generations
32271 Switch to an existing system generation. This action atomically
32272 switches the system profile to the specified system generation. It
32273 also rearranges the system's existing bootloader menu entries. It
32274 makes the menu entry for the specified system generation the default,
32275 and it moves the entries for the other generations to a submenu, if
32276 supported by the bootloader being used. The next time the system
32277 boots, it will use the specified system generation.
32279 The bootloader itself is not being reinstalled when using this
32280 command. Thus, the installed bootloader is used with an updated
32281 configuration file.
32283 The target generation can be specified explicitly by its generation
32284 number. For example, the following invocation would switch to system
32288 guix system switch-generation 7
32291 The target generation can also be specified relative to the current
32292 generation with the form @code{+N} or @code{-N}, where @code{+3} means
32293 ``3 generations ahead of the current generation,'' and @code{-1} means
32294 ``1 generation prior to the current generation.'' When specifying a
32295 negative value such as @code{-1}, you must precede it with @code{--} to
32296 prevent it from being parsed as an option. For example:
32299 guix system switch-generation -- -1
32302 Currently, the effect of invoking this action is @emph{only} to switch
32303 the system profile to an existing generation and rearrange the
32304 bootloader menu entries. To actually start using the target system
32305 generation, you must reboot after running this action. In the future,
32306 it will be updated to do the same things as @command{reconfigure},
32307 like activating and deactivating services.
32309 This action will fail if the specified generation does not exist.
32312 @cindex rolling back
32313 Switch to the preceding system generation. The next time the system
32314 boots, it will use the preceding system generation. This is the inverse
32315 of @command{reconfigure}, and it is exactly the same as invoking
32316 @command{switch-generation} with an argument of @code{-1}.
32318 Currently, as with @command{switch-generation}, you must reboot after
32319 running this action to actually start using the preceding system
32322 @item delete-generations
32323 @cindex deleting system generations
32324 @cindex saving space
32325 Delete system generations, making them candidates for garbage collection
32326 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
32329 This works in the same way as @samp{guix package --delete-generations}
32330 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
32331 arguments, all system generations but the current one are deleted:
32334 guix system delete-generations
32337 You can also select the generations you want to delete. The example below
32338 deletes all the system generations that are more than two month old:
32341 guix system delete-generations 2m
32344 Running this command automatically reinstalls the bootloader with an updated
32345 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
32346 longer lists the generations that have been deleted.
32349 Build the derivation of the operating system, which includes all the
32350 configuration files and programs needed to boot and run the system.
32351 This action does not actually install anything.
32354 Populate the given directory with all the files necessary to run the
32355 operating system specified in @var{file}. This is useful for first-time
32356 installations of Guix System. For instance:
32359 guix system init my-os-config.scm /mnt
32362 copies to @file{/mnt} all the store items required by the configuration
32363 specified in @file{my-os-config.scm}. This includes configuration
32364 files, packages, and so on. It also creates other essential files
32365 needed for the system to operate correctly---e.g., the @file{/etc},
32366 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
32368 This command also installs bootloader on the target specified in
32369 @file{my-os-config}, unless the @option{--no-bootloader} option was
32373 @cindex virtual machine
32375 @anchor{guix system vm}
32376 Build a virtual machine that contains the operating system declared in
32377 @var{file}, and return a script to run that virtual machine (VM).
32380 The @code{vm} action and others below
32381 can use KVM support in the Linux-libre kernel. Specifically, if the
32382 machine has hardware virtualization support, the corresponding
32383 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
32384 must exist and be readable and writable by the user and by the
32385 build users of the daemon (@pxref{Build Environment Setup}).
32388 Arguments given to the script are passed to QEMU as in the example
32389 below, which enables networking and requests 1@tie{}GiB of RAM for the
32393 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
32396 The VM shares its store with the host system.
32398 Additional file systems can be shared between the host and the VM using
32399 the @option{--share} and @option{--expose} command-line options: the former
32400 specifies a directory to be shared with write access, while the latter
32401 provides read-only access to the shared directory.
32403 The example below creates a VM in which the user's home directory is
32404 accessible read-only, and where the @file{/exchange} directory is a
32405 read-write mapping of @file{$HOME/tmp} on the host:
32408 guix system vm my-config.scm \
32409 --expose=$HOME --share=$HOME/tmp=/exchange
32412 On GNU/Linux, the default is to boot directly to the kernel; this has
32413 the advantage of requiring only a very tiny root disk image since the
32414 store of the host can then be mounted.
32416 The @option{--full-boot} option forces a complete boot sequence, starting
32417 with the bootloader. This requires more disk space since a root image
32418 containing at least the kernel, initrd, and bootloader data files must
32419 be created. The @option{--image-size} option can be used to specify the
32422 @cindex System images, creation in various formats
32423 @cindex Creating system images in various formats
32426 @itemx docker-image
32427 Return a virtual machine, disk image, or Docker image of the operating
32428 system declared in @var{file} that stands alone. By default,
32429 @command{guix system} estimates the size of the image needed to store
32430 the system, but you can use the @option{--image-size} option to specify
32431 a value. Docker images are built to contain exactly what they need, so
32432 the @option{--image-size} option is ignored in the case of
32433 @code{docker-image}.
32435 @cindex image, creating disk images
32436 The @code{image} command can produce various image types. The
32437 image type can be selected using the @option{--image-type} option. It
32438 defaults to @code{efi-raw}. When its value is @code{iso9660}, the
32439 @option{--label} option can be used to specify a volume ID with
32440 @code{image}. By default, the root file system of a disk image is
32441 mounted non-volatile; the @option{--volatile} option can be provided to
32442 make it volatile instead. When using @code{image}, the bootloader
32443 installed on the generated image is taken from the provided
32444 @code{operating-system} definition. The following example demonstrates
32445 how to generate an image that uses the @code{grub-efi-bootloader}
32446 bootloader and boot it with QEMU:
32449 image=$(guix system image --image-type=qcow2 \
32450 gnu/system/examples/lightweight-desktop.tmpl)
32451 cp $image /tmp/my-image.qcow2
32452 chmod +w /tmp/my-image.qcow2
32453 qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
32454 -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
32457 When using the @code{efi-raw} image type, a raw disk image is produced;
32458 it can be copied as is to a USB stick, for instance. Assuming
32459 @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
32460 the image to it using the following command:
32463 # dd if=$(guix system image my-os.scm) of=/dev/sdc status=progress
32466 The @code{--list-image-types} command lists all the available image
32469 @cindex vm-image, creating virtual machine images
32470 When using @code{vm-image}, the returned image is in qcow2 format, which
32471 the QEMU emulator can efficiently use. @xref{Running Guix in a VM}, for
32472 more information on how to run the image in a virtual machine. The
32473 @code{grub-bootloader} bootloader is always used independently of what
32474 is declared in the @code{operating-system} file passed as argument.
32475 This is to make it easier to work with QEMU, which uses the SeaBIOS BIOS
32476 by default, expecting a bootloader to be installed in the Master Boot
32479 @cindex docker-image, creating docker images
32480 When using @code{docker-image}, a Docker image is produced. Guix builds
32481 the image from scratch, not from a pre-existing Docker base image. As a
32482 result, it contains @emph{exactly} what you define in the operating
32483 system configuration file. You can then load the image and launch a
32484 Docker container using commands like the following:
32487 image_id="`docker load < guix-system-docker-image.tar.gz`"
32488 container_id="`docker create $image_id`"
32489 docker start $container_id
32492 This command starts a new Docker container from the specified image. It
32493 will boot the Guix system in the usual manner, which means it will
32494 start any services you have defined in the operating system
32495 configuration. You can get an interactive shell running in the container
32496 using @command{docker exec}:
32499 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
32502 Depending on what you run in the Docker container, it
32503 may be necessary to give the container additional permissions. For
32504 example, if you intend to build software using Guix inside of the Docker
32505 container, you may need to pass the @option{--privileged} option to
32506 @code{docker create}.
32508 Last, the @option{--network} option applies to @command{guix system
32509 docker-image}: it produces an image where network is supposedly shared
32510 with the host, and thus without services like nscd or NetworkManager.
32513 Return a script to run the operating system declared in @var{file}
32514 within a container. Containers are a set of lightweight isolation
32515 mechanisms provided by the kernel Linux-libre. Containers are
32516 substantially less resource-demanding than full virtual machines since
32517 the kernel, shared objects, and other resources can be shared with the
32518 host system; this also means they provide thinner isolation.
32520 Currently, the script must be run as root in order to support more than
32521 a single user and group. The container shares its store with the host
32524 As with the @code{vm} action (@pxref{guix system vm}), additional file
32525 systems to be shared between the host and container can be specified
32526 using the @option{--share} and @option{--expose} options:
32529 guix system container my-config.scm \
32530 --expose=$HOME --share=$HOME/tmp=/exchange
32534 This option requires Linux-libre 3.19 or newer.
32539 @var{options} can contain any of the common build options (@pxref{Common
32540 Build Options}). In addition, @var{options} can contain one of the
32544 @item --expression=@var{expr}
32545 @itemx -e @var{expr}
32546 Consider the operating-system @var{expr} evaluates to.
32547 This is an alternative to specifying a file which evaluates to an
32549 This is used to generate the Guix system installer @pxref{Building the
32550 Installation Image}).
32552 @item --system=@var{system}
32553 @itemx -s @var{system}
32554 Attempt to build for @var{system} instead of the host system type.
32555 This works as per @command{guix build} (@pxref{Invoking guix build}).
32559 Return the derivation file name of the given operating system without
32562 @cindex provenance tracking, of the operating system
32563 @item --save-provenance
32564 As discussed above, @command{guix system init} and @command{guix system
32565 reconfigure} always save provenance information @i{via} a dedicated
32566 service (@pxref{Service Reference, @code{provenance-service-type}}).
32567 However, other commands don't do that by default. If you wish to, say,
32568 create a virtual machine image that contains provenance information, you
32572 guix system vm-image --save-provenance config.scm
32575 That way, the resulting image will effectively ``embed its own source''
32576 in the form of meta-data in @file{/run/current-system}. With that
32577 information, one can rebuild the image to make sure it really contains
32578 what it pretends to contain; or they could use that to derive a variant
32581 @item --image-type=@var{type}
32582 @itemx -t @var{type}
32583 For the @code{image} action, create an image with given @var{type}.
32585 When this option is omitted, @command{guix system} uses the
32586 @code{efi-raw} image type.
32588 @cindex ISO-9660 format
32589 @cindex CD image format
32590 @cindex DVD image format
32591 @option{--image-type=iso9660} produces an ISO-9660 image, suitable
32592 for burning on CDs and DVDs.
32594 @item --image-size=@var{size}
32595 For the @code{vm-image} and @code{image} actions, create an image
32596 of the given @var{size}. @var{size} may be a number of bytes, or it may
32597 include a unit as a suffix (@pxref{Block size, size specifications,,
32598 coreutils, GNU Coreutils}).
32600 When this option is omitted, @command{guix system} computes an estimate
32601 of the image size as a function of the size of the system declared in
32606 For the @code{container} action, allow containers to access the host network,
32607 that is, do not create a network namespace.
32609 @item --root=@var{file}
32610 @itemx -r @var{file}
32611 Make @var{file} a symlink to the result, and register it as a garbage
32614 @item --skip-checks
32615 Skip pre-installation safety checks.
32617 By default, @command{guix system init} and @command{guix system
32618 reconfigure} perform safety checks: they make sure the file systems that
32619 appear in the @code{operating-system} declaration actually exist
32620 (@pxref{File Systems}), and that any Linux kernel modules that may be
32621 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
32622 RAM Disk}). Passing this option skips these tests altogether.
32624 @item --allow-downgrades
32625 Instruct @command{guix system reconfigure} to allow system downgrades.
32627 By default, @command{reconfigure} prevents you from downgrading your
32628 system. It achieves that by comparing the provenance info of your
32629 system (shown by @command{guix system describe}) with that of your
32630 @command{guix} command (shown by @command{guix describe}). If the
32631 commits for @command{guix} are not descendants of those used for your
32632 system, @command{guix system reconfigure} errors out. Passing
32633 @option{--allow-downgrades} allows you to bypass these checks.
32636 Make sure you understand its security implications before using
32637 @option{--allow-downgrades}.
32641 @cindex on-error strategy
32642 @cindex error strategy
32643 @item --on-error=@var{strategy}
32644 Apply @var{strategy} when an error occurs when reading @var{file}.
32645 @var{strategy} may be one of the following:
32648 @item nothing-special
32649 Report the error concisely and exit. This is the default strategy.
32652 Likewise, but also display a backtrace.
32655 Report the error and enter Guile's debugger. From there, you can run
32656 commands such as @code{,bt} to get a backtrace, @code{,locals} to
32657 display local variable values, and more generally inspect the state of the
32658 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
32659 a list of available debugging commands.
32663 Once you have built, configured, re-configured, and re-re-configured
32664 your Guix installation, you may find it useful to list the operating
32665 system generations available on disk---and that you can choose from the
32666 bootloader boot menu:
32671 Describe the current system generation: its file name, the kernel and
32672 bootloader used, etc., as well as provenance information when available.
32674 @item list-generations
32675 List a summary of each generation of the operating system available on
32676 disk, in a human-readable way. This is similar to the
32677 @option{--list-generations} option of @command{guix package}
32678 (@pxref{Invoking guix package}).
32680 Optionally, one can specify a pattern, with the same syntax that is used
32681 in @command{guix package --list-generations}, to restrict the list of
32682 generations displayed. For instance, the following command displays
32683 generations that are up to 10 days old:
32686 $ guix system list-generations 10d
32691 The @command{guix system} command has even more to offer! The following
32692 sub-commands allow you to visualize how your system services relate to
32695 @anchor{system-extension-graph}
32698 @item extension-graph
32699 Emit to standard output the @dfn{service
32700 extension graph} of the operating system defined in @var{file}
32701 (@pxref{Service Composition}, for more information on service
32702 extensions). By default the output is in Dot/Graphviz format, but you
32703 can choose a different format with @option{--graph-backend}, as with
32704 @command{guix graph} (@pxref{Invoking guix graph, @option{--backend}}):
32709 $ guix system extension-graph @var{file} | xdot -
32712 shows the extension relations among services.
32714 @anchor{system-shepherd-graph}
32715 @item shepherd-graph
32716 Emit to standard output the @dfn{dependency
32717 graph} of shepherd services of the operating system defined in
32718 @var{file}. @xref{Shepherd Services}, for more information and for an
32721 Again, the default output format is Dot/Graphviz, but you can pass
32722 @option{--graph-backend} to select a different one.
32726 @node Invoking guix deploy
32727 @section Invoking @code{guix deploy}
32729 We've already seen @code{operating-system} declarations used to manage a
32730 machine's configuration locally. Suppose you need to configure multiple
32731 machines, though---perhaps you're managing a service on the web that's
32732 comprised of several servers. @command{guix deploy} enables you to use those
32733 same @code{operating-system} declarations to manage multiple remote hosts at
32734 once as a logical ``deployment''.
32737 The functionality described in this section is still under development
32738 and is subject to change. Get in touch with us on
32739 @email{guix-devel@@gnu.org}!
32743 guix deploy @var{file}
32746 Such an invocation will deploy the machines that the code within @var{file}
32747 evaluates to. As an example, @var{file} might contain a definition like this:
32750 ;; This is a Guix deployment of a "bare bones" setup, with
32751 ;; no X11 display server, to a machine with an SSH daemon
32752 ;; listening on localhost:2222. A configuration such as this
32753 ;; may be appropriate for virtual machine with ports
32754 ;; forwarded to the host's loopback interface.
32756 (use-service-modules networking ssh)
32757 (use-package-modules bootloaders)
32761 (host-name "gnu-deployed")
32762 (timezone "Etc/UTC")
32763 (bootloader (bootloader-configuration
32764 (bootloader grub-bootloader)
32765 (target "/dev/vda")
32766 (terminal-outputs '(console))))
32767 (file-systems (cons (file-system
32769 (device "/dev/vda1")
32771 %base-file-systems))
32773 (append (list (service dhcp-client-service-type)
32774 (service openssh-service-type
32775 (openssh-configuration
32776 (permit-root-login #t)
32777 (allow-empty-passwords? #t))))
32781 (operating-system %system)
32782 (environment managed-host-environment-type)
32783 (configuration (machine-ssh-configuration
32784 (host-name "localhost")
32785 (system "x86_64-linux")
32787 (identity "./id_rsa")
32791 The file should evaluate to a list of @var{machine} objects. This example,
32792 upon being deployed, will create a new generation on the remote system
32793 realizing the @code{operating-system} declaration @code{%system}.
32794 @code{environment} and @code{configuration} specify how the machine should be
32795 provisioned---that is, how the computing resources should be created and
32796 managed. The above example does not create any resources, as a
32797 @code{'managed-host} is a machine that is already running the Guix system and
32798 available over the network. This is a particularly simple case; a more
32799 complex deployment may involve, for example, starting virtual machines through
32800 a Virtual Private Server (VPS) provider. In such a case, a different
32801 @var{environment} type would be used.
32803 Do note that you first need to generate a key pair on the coordinator machine
32804 to allow the daemon to export signed archives of files from the store
32805 (@pxref{Invoking guix archive}), though this step is automatic on Guix
32809 # guix archive --generate-key
32813 Each target machine must authorize the key of the master machine so that it
32814 accepts store items it receives from the coordinator:
32817 # guix archive --authorize < coordinator-public-key.txt
32820 @code{user}, in this example, specifies the name of the user account to log in
32821 as to perform the deployment. Its default value is @code{root}, but root
32822 login over SSH may be forbidden in some cases. To work around this,
32823 @command{guix deploy} can log in as an unprivileged user and employ
32824 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
32825 currently installed on the remote and can be invoked non-interactively as
32826 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
32827 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
32828 be accomplished with the following operating system configuration snippet:
32832 (gnu system)) ;for %sudoers-specification
32834 (define %user "username")
32839 (plain-file "sudoers"
32840 (string-append (plain-file-content %sudoers-specification)
32841 (format #f "~a ALL = NOPASSWD: ALL~%"
32846 For more information regarding the format of the @file{sudoers} file,
32847 consult @command{man sudoers}.
32849 @deftp {Data Type} machine
32850 This is the data type representing a single machine in a heterogeneous Guix
32854 @item @code{operating-system}
32855 The object of the operating system configuration to deploy.
32857 @item @code{environment}
32858 An @code{environment-type} describing how the machine should be provisioned.
32860 @item @code{configuration} (default: @code{#f})
32861 An object describing the configuration for the machine's @code{environment}.
32862 If the @code{environment} has a default configuration, @code{#f} may be used.
32863 If @code{#f} is used for an environment with no default configuration,
32864 however, an error will be thrown.
32868 @deftp {Data Type} machine-ssh-configuration
32869 This is the data type representing the SSH client parameters for a machine
32870 with an @code{environment} of @code{managed-host-environment-type}.
32873 @item @code{host-name}
32874 @item @code{build-locally?} (default: @code{#t})
32875 If false, system derivations will be built on the machine being deployed to.
32876 @item @code{system}
32877 The system type describing the architecture of the machine being deployed
32878 to---e.g., @code{"x86_64-linux"}.
32879 @item @code{authorize?} (default: @code{#t})
32880 If true, the coordinator's signing key will be added to the remote's ACL
32882 @item @code{port} (default: @code{22})
32883 @item @code{user} (default: @code{"root"})
32884 @item @code{identity} (default: @code{#f})
32885 If specified, the path to the SSH private key to use to authenticate with the
32888 @item @code{host-key} (default: @code{#f})
32889 This should be the SSH host key of the machine, which looks like this:
32892 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
32895 When @code{host-key} is @code{#f}, the server is authenticated against
32896 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
32899 @item @code{allow-downgrades?} (default: @code{#f})
32900 Whether to allow potential downgrades.
32902 Like @command{guix system reconfigure}, @command{guix deploy} compares
32903 the channel commits currently deployed on the remote host (as returned
32904 by @command{guix system describe}) to those currently in use (as
32905 returned by @command{guix describe}) to determine whether commits
32906 currently in use are descendants of those deployed. When this is not
32907 the case and @code{allow-downgrades?} is false, it raises an error.
32908 This ensures you do not accidentally downgrade remote machines.
32912 @deftp {Data Type} digital-ocean-configuration
32913 This is the data type describing the Droplet that should be created for a
32914 machine with an @code{environment} of @code{digital-ocean-environment-type}.
32917 @item @code{ssh-key}
32918 The path to the SSH private key to use to authenticate with the remote
32919 host. In the future, this field may not exist.
32921 A list of string ``tags'' that uniquely identify the machine. Must be given
32922 such that no two machines in the deployment have the same set of tags.
32923 @item @code{region}
32924 A Digital Ocean region slug, such as @code{"nyc3"}.
32926 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
32927 @item @code{enable-ipv6?}
32928 Whether or not the droplet should be created with IPv6 networking.
32932 @node Running Guix in a VM
32933 @section Running Guix in a Virtual Machine
32935 @cindex virtual machine
32936 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
32938 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
32939 This image is a compressed image in QCOW format. You will first need to
32940 decompress with @command{xz -d}, and then you can pass it to an emulator such
32941 as QEMU (see below for details).
32943 This image boots the Xfce graphical environment and it contains some
32944 commonly used tools. You can install more software in the image by running
32945 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
32946 also reconfigure the system based on its initial configuration file available
32947 as @file{/run/current-system/configuration.scm} (@pxref{Using the
32948 Configuration System}).
32950 Instead of using this pre-built image, one can also build their own virtual
32951 machine image using @command{guix system vm-image} (@pxref{Invoking guix
32952 system}). The returned image is in qcow2 format, which the
32953 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
32956 If you built your own image, you must copy it out of the store
32957 (@pxref{The Store}) and give yourself permission to write to the copy
32958 before you can use it. When invoking QEMU, you must choose a system
32959 emulator that is suitable for your hardware platform. Here is a minimal
32960 QEMU invocation that will boot the result of @command{guix system
32961 vm-image} on x86_64 hardware:
32964 $ qemu-system-x86_64 \
32965 -nic user,model=virtio-net-pci \
32966 -enable-kvm -m 1024 \
32967 -device virtio-blk,drive=myhd \
32968 -drive if=none,file=/tmp/qemu-image,id=myhd
32971 Here is what each of these options means:
32974 @item qemu-system-x86_64
32975 This specifies the hardware platform to emulate. This should match the
32978 @item -nic user,model=virtio-net-pci
32979 Enable the unprivileged user-mode network stack. The guest OS can
32980 access the host but not vice versa. This is the simplest way to get the
32981 guest OS online. @code{model} specifies which network device to emulate:
32982 @code{virtio-net-pci} is a special device made for virtualized operating
32983 systems and recommended for most uses. Assuming your hardware platform is
32984 x86_64, you can get a list of available NIC models by running
32985 @command{qemu-system-x86_64 -nic model=help}.
32988 If your system has hardware virtualization extensions, enabling the
32989 virtual machine support (KVM) of the Linux kernel will make things run
32992 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
32994 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
32995 which may be insufficient for some operations.
32997 @item -device virtio-blk,drive=myhd
32998 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
32999 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
33000 better performance than if it were emulating a complete disk drive. See the
33001 QEMU and KVM documentation for more info.
33003 @item -drive if=none,file=/tmp/qemu-image,id=myhd
33004 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
33005 store of the ``myhd'' drive.
33008 The default @command{run-vm.sh} script that is returned by an invocation of
33009 @command{guix system vm} does not add a @command{-nic user} flag by default.
33010 To get network access from within the vm add the @code{(dhcp-client-service)}
33011 to your system definition and start the VM using
33012 @command{`guix system vm config.scm` -nic user}. An important caveat of using
33013 @command{-nic user} for networking is that @command{ping} will not work, because
33014 it uses the ICMP protocol. You'll have to use a different command to check for
33015 network connectivity, for example @command{guix download}.
33017 @subsection Connecting Through SSH
33021 To enable SSH inside a VM you need to add an SSH server like
33022 @code{openssh-service-type} to your VM (@pxref{Networking Services,
33023 @code{openssh-service-type}}). In addition you need to forward the SSH port,
33024 22 by default, to the host. You can do this with
33027 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
33030 To connect to the VM you can run
33033 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
33036 The @command{-p} tells @command{ssh} the port you want to connect to.
33037 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
33038 every time you modify your @command{config.scm} file and the
33039 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
33040 connection to an unknown host every time you connect.
33042 @subsection Using @command{virt-viewer} with Spice
33044 As an alternative to the default @command{qemu} graphical client you can
33045 use the @command{remote-viewer} from the @command{virt-viewer} package. To
33046 connect pass the @command{-spice port=5930,disable-ticketing} flag to
33047 @command{qemu}. See previous section for further information on how to do this.
33049 Spice also allows you to do some nice stuff like share your clipboard with your
33050 VM@. To enable that you'll also have to pass the following flags to @command{qemu}:
33053 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
33054 -chardev spicevmc,name=vdagent,id=vdagent
33055 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
33056 name=com.redhat.spice.0
33059 You'll also need to add the @code{(spice-vdagent-service)} to your
33060 system definition (@pxref{Miscellaneous Services, Spice service}).
33062 @node Defining Services
33063 @section Defining Services
33065 The previous sections show the available services and how one can combine
33066 them in an @code{operating-system} declaration. But how do we define
33067 them in the first place? And what is a service anyway?
33070 * Service Composition:: The model for composing services.
33071 * Service Types and Services:: Types and services.
33072 * Service Reference:: API reference.
33073 * Shepherd Services:: A particular type of service.
33076 @node Service Composition
33077 @subsection Service Composition
33081 Here we define a @dfn{service} as, broadly, something that extends the
33082 functionality of the operating system. Often a service is a process---a
33083 @dfn{daemon}---started when the system boots: a secure shell server, a
33084 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
33085 whose execution can be triggered by another daemon---e.g., an FTP server
33086 started by @command{inetd} or a D-Bus service activated by
33087 @command{dbus-daemon}. Occasionally, a service does not map to a
33088 daemon. For instance, the ``account'' service collects user accounts
33089 and makes sure they exist when the system runs; the ``udev'' service
33090 collects device management rules and makes them available to the eudev
33091 daemon; the @file{/etc} service populates the @file{/etc} directory
33094 @cindex service extensions
33095 Guix system services are connected by @dfn{extensions}. For instance, the
33096 secure shell service @emph{extends} the Shepherd---the
33097 initialization system, running as PID@tie{}1---by giving it the command
33098 lines to start and stop the secure shell daemon (@pxref{Networking
33099 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
33100 service by passing it its @file{.service} specification, and extends the
33101 udev service by passing it device management rules (@pxref{Desktop
33102 Services, @code{upower-service}}); the Guix daemon service extends the
33103 Shepherd by passing it the command lines to start and stop the daemon,
33104 and extends the account service by passing it a list of required build
33105 user accounts (@pxref{Base Services}).
33107 All in all, services and their ``extends'' relations form a directed
33108 acyclic graph (DAG). If we represent services as boxes and extensions
33109 as arrows, a typical system might provide something like this:
33111 @image{images/service-graph,,5in,Typical service extension graph.}
33113 @cindex system service
33114 At the bottom, we see the @dfn{system service}, which produces the
33115 directory containing everything to run and boot the system, as returned
33116 by the @command{guix system build} command. @xref{Service Reference},
33117 to learn about the other service types shown here.
33118 @xref{system-extension-graph, the @command{guix system extension-graph}
33119 command}, for information on how to generate this representation for a
33120 particular operating system definition.
33122 @cindex service types
33123 Technically, developers can define @dfn{service types} to express these
33124 relations. There can be any number of services of a given type on the
33125 system---for instance, a system running two instances of the GNU secure
33126 shell server (lsh) has two instances of @code{lsh-service-type}, with
33127 different parameters.
33129 The following section describes the programming interface for service
33130 types and services.
33132 @node Service Types and Services
33133 @subsection Service Types and Services
33135 A @dfn{service type} is a node in the DAG described above. Let us start
33136 with a simple example, the service type for the Guix build daemon
33137 (@pxref{Invoking guix-daemon}):
33140 (define guix-service-type
33144 (list (service-extension shepherd-root-service-type guix-shepherd-service)
33145 (service-extension account-service-type guix-accounts)
33146 (service-extension activation-service-type guix-activation)))
33147 (default-value (guix-configuration))))
33151 It defines three things:
33155 A name, whose sole purpose is to make inspection and debugging easier.
33158 A list of @dfn{service extensions}, where each extension designates the
33159 target service type and a procedure that, given the parameters of the
33160 service, returns a list of objects to extend the service of that type.
33162 Every service type has at least one service extension. The only
33163 exception is the @dfn{boot service type}, which is the ultimate service.
33166 Optionally, a default value for instances of this type.
33169 In this example, @code{guix-service-type} extends three services:
33172 @item shepherd-root-service-type
33173 The @code{guix-shepherd-service} procedure defines how the Shepherd
33174 service is extended. Namely, it returns a @code{<shepherd-service>}
33175 object that defines how @command{guix-daemon} is started and stopped
33176 (@pxref{Shepherd Services}).
33178 @item account-service-type
33179 This extension for this service is computed by @code{guix-accounts},
33180 which returns a list of @code{user-group} and @code{user-account}
33181 objects representing the build user accounts (@pxref{Invoking
33184 @item activation-service-type
33185 Here @code{guix-activation} is a procedure that returns a gexp, which is
33186 a code snippet to run at ``activation time''---e.g., when the service is
33190 A service of this type is instantiated like this:
33193 (service guix-service-type
33194 (guix-configuration
33196 (extra-options '("--gc-keep-derivations"))))
33199 The second argument to the @code{service} form is a value representing
33200 the parameters of this specific service instance.
33201 @xref{guix-configuration-type, @code{guix-configuration}}, for
33202 information about the @code{guix-configuration} data type. When the
33203 value is omitted, the default value specified by
33204 @code{guix-service-type} is used:
33207 (service guix-service-type)
33210 @code{guix-service-type} is quite simple because it extends other
33211 services but is not extensible itself.
33213 @c @subsubsubsection Extensible Service Types
33215 The service type for an @emph{extensible} service looks like this:
33218 (define udev-service-type
33219 (service-type (name 'udev)
33221 (list (service-extension shepherd-root-service-type
33222 udev-shepherd-service)))
33224 (compose concatenate) ;concatenate the list of rules
33225 (extend (lambda (config rules)
33227 (($ <udev-configuration> udev initial-rules)
33228 (udev-configuration
33229 (udev udev) ;the udev package to use
33230 (rules (append initial-rules rules)))))))))
33233 This is the service type for the
33234 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
33235 management daemon}. Compared to the previous example, in addition to an
33236 extension of @code{shepherd-root-service-type}, we see two new fields:
33240 This is the procedure to @dfn{compose} the list of extensions to
33241 services of this type.
33243 Services can extend the udev service by passing it lists of rules; we
33244 compose those extensions simply by concatenating them.
33247 This procedure defines how the value of the service is @dfn{extended} with
33248 the composition of the extensions.
33250 Udev extensions are composed into a list of rules, but the udev service
33251 value is itself a @code{<udev-configuration>} record. So here, we
33252 extend that record by appending the list of rules it contains to the
33253 list of contributed rules.
33256 This is a string giving an overview of the service type. The string can
33257 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
33258 @command{guix system search} command searches these strings and displays
33259 them (@pxref{Invoking guix system}).
33262 There can be only one instance of an extensible service type such as
33263 @code{udev-service-type}. If there were more, the
33264 @code{service-extension} specifications would be ambiguous.
33266 Still here? The next section provides a reference of the programming
33267 interface for services.
33269 @node Service Reference
33270 @subsection Service Reference
33272 We have seen an overview of service types (@pxref{Service Types and
33273 Services}). This section provides a reference on how to manipulate
33274 services and service types. This interface is provided by the
33275 @code{(gnu services)} module.
33277 @deffn {Scheme Procedure} service @var{type} [@var{value}]
33278 Return a new service of @var{type}, a @code{<service-type>} object (see
33279 below). @var{value} can be any object; it represents the parameters of
33280 this particular service instance.
33282 When @var{value} is omitted, the default value specified by @var{type}
33283 is used; if @var{type} does not specify a default value, an error is
33286 For instance, this:
33289 (service openssh-service-type)
33293 is equivalent to this:
33296 (service openssh-service-type
33297 (openssh-configuration))
33300 In both cases the result is an instance of @code{openssh-service-type}
33301 with the default configuration.
33304 @deffn {Scheme Procedure} service? @var{obj}
33305 Return true if @var{obj} is a service.
33308 @deffn {Scheme Procedure} service-kind @var{service}
33309 Return the type of @var{service}---i.e., a @code{<service-type>} object.
33312 @deffn {Scheme Procedure} service-value @var{service}
33313 Return the value associated with @var{service}. It represents its
33317 Here is an example of how a service is created and manipulated:
33321 (service nginx-service-type
33322 (nginx-configuration
33324 (log-directory log-directory)
33325 (run-directory run-directory)
33326 (file config-file))))
33331 (eq? (service-kind s) nginx-service-type)
33335 The @code{modify-services} form provides a handy way to change the
33336 parameters of some of the services of a list such as
33337 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
33338 evaluates to a list of services. Of course, you could always use
33339 standard list combinators such as @code{map} and @code{fold} to do that
33340 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
33341 @code{modify-services} simply provides a more concise form for this
33344 @deffn {Scheme Syntax} modify-services @var{services} @
33345 (@var{type} @var{variable} => @var{body}) @dots{}
33347 Modify the services listed in @var{services} according to the given
33348 clauses. Each clause has the form:
33351 (@var{type} @var{variable} => @var{body})
33354 where @var{type} is a service type---e.g.,
33355 @code{guix-service-type}---and @var{variable} is an identifier that is
33356 bound within the @var{body} to the service parameters---e.g., a
33357 @code{guix-configuration} instance---of the original service of that
33360 The @var{body} should evaluate to the new service parameters, which will
33361 be used to configure the new service. This new service will replace the
33362 original in the resulting list. Because a service's service parameters
33363 are created using @code{define-record-type*}, you can write a succinct
33364 @var{body} that evaluates to the new service parameters by using the
33365 @code{inherit} feature that @code{define-record-type*} provides.
33367 @xref{Using the Configuration System}, for example usage.
33371 Next comes the programming interface for service types. This is
33372 something you want to know when writing new service definitions, but not
33373 necessarily when simply looking for ways to customize your
33374 @code{operating-system} declaration.
33376 @deftp {Data Type} service-type
33377 @cindex service type
33378 This is the representation of a @dfn{service type} (@pxref{Service Types
33383 This is a symbol, used only to simplify inspection and debugging.
33385 @item @code{extensions}
33386 A non-empty list of @code{<service-extension>} objects (see below).
33388 @item @code{compose} (default: @code{#f})
33389 If this is @code{#f}, then the service type denotes services that cannot
33390 be extended---i.e., services that do not receive ``values'' from other
33393 Otherwise, it must be a one-argument procedure. The procedure is called
33394 by @code{fold-services} and is passed a list of values collected from
33395 extensions. It may return any single value.
33397 @item @code{extend} (default: @code{#f})
33398 If this is @code{#f}, services of this type cannot be extended.
33400 Otherwise, it must be a two-argument procedure: @code{fold-services}
33401 calls it, passing it the initial value of the service as the first
33402 argument and the result of applying @code{compose} to the extension
33403 values as the second argument. It must return a value that is a valid
33404 parameter value for the service instance.
33406 @item @code{description}
33407 This is a string, possibly using Texinfo markup, describing in a couple
33408 of sentences what the service is about. This string allows users to
33409 find about the service through @command{guix system search}
33410 (@pxref{Invoking guix system}).
33412 @item @code{default-value} (default: @code{&no-default-value})
33413 The default value associated for instances of this service type. This
33414 allows users to use the @code{service} form without its second argument:
33417 (service @var{type})
33420 The returned service in this case has the default value specified by
33424 @xref{Service Types and Services}, for examples.
33427 @deffn {Scheme Procedure} service-extension @var{target-type} @
33429 Return a new extension for services of type @var{target-type}.
33430 @var{compute} must be a one-argument procedure: @code{fold-services}
33431 calls it, passing it the value associated with the service that provides
33432 the extension; it must return a valid value for the target service.
33435 @deffn {Scheme Procedure} service-extension? @var{obj}
33436 Return true if @var{obj} is a service extension.
33439 Occasionally, you might want to simply extend an existing service. This
33440 involves creating a new service type and specifying the extension of
33441 interest, which can be verbose; the @code{simple-service} procedure
33442 provides a shorthand for this.
33444 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
33445 Return a service that extends @var{target} with @var{value}. This works
33446 by creating a singleton service type @var{name}, of which the returned
33447 service is an instance.
33449 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
33453 (simple-service 'my-mcron-job mcron-service-type
33454 #~(job '(next-hour (3)) "guix gc -F 2G"))
33458 At the core of the service abstraction lies the @code{fold-services}
33459 procedure, which is responsible for ``compiling'' a list of services
33460 down to a single directory that contains everything needed to boot and
33461 run the system---the directory shown by the @command{guix system build}
33462 command (@pxref{Invoking guix system}). In essence, it propagates
33463 service extensions down the service graph, updating each node parameters
33464 on the way, until it reaches the root node.
33466 @deffn {Scheme Procedure} fold-services @var{services} @
33467 [#:target-type @var{system-service-type}]
33468 Fold @var{services} by propagating their extensions down to the root of
33469 type @var{target-type}; return the root service adjusted accordingly.
33472 Lastly, the @code{(gnu services)} module also defines several essential
33473 service types, some of which are listed below.
33475 @defvr {Scheme Variable} system-service-type
33476 This is the root of the service graph. It produces the system directory
33477 as returned by the @command{guix system build} command.
33480 @defvr {Scheme Variable} boot-service-type
33481 The type of the ``boot service'', which produces the @dfn{boot script}.
33482 The boot script is what the initial RAM disk runs when booting.
33485 @defvr {Scheme Variable} etc-service-type
33486 The type of the @file{/etc} service. This service is used to create
33487 files under @file{/etc} and can be extended by
33488 passing it name/file tuples such as:
33491 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
33494 In this example, the effect would be to add an @file{/etc/issue} file
33495 pointing to the given file.
33498 @defvr {Scheme Variable} setuid-program-service-type
33499 Type for the ``setuid-program service''. This service collects lists of
33500 executable file names, passed as gexps, and adds them to the set of
33501 setuid-root programs on the system (@pxref{Setuid Programs}).
33504 @defvr {Scheme Variable} profile-service-type
33505 Type of the service that populates the @dfn{system profile}---i.e., the
33506 programs under @file{/run/current-system/profile}. Other services can
33507 extend it by passing it lists of packages to add to the system profile.
33510 @cindex provenance tracking, of the operating system
33511 @anchor{provenance-service-type}
33512 @defvr {Scheme Variable} provenance-service-type
33513 This is the type of the service that records @dfn{provenance meta-data}
33514 in the system itself. It creates several files under
33515 @file{/run/current-system}:
33519 This is a ``channel file'' that can be passed to @command{guix pull -C}
33520 or @command{guix time-machine -C}, and which describes the channels used
33521 to build the system, if that information was available
33522 (@pxref{Channels}).
33524 @item configuration.scm
33525 This is the file that was passed as the value for this
33526 @code{provenance-service-type} service. By default, @command{guix
33527 system reconfigure} automatically passes the OS configuration file it
33528 received on the command line.
33531 This contains the same information as the two other files but in a
33532 format that is more readily processable.
33535 In general, these two pieces of information (channels and configuration
33536 file) are enough to reproduce the operating system ``from source''.
33539 This information is necessary to rebuild your operating system, but it
33540 is not always sufficient. In particular, @file{configuration.scm}
33541 itself is insufficient if it is not self-contained---if it refers to
33542 external Guile modules or to extra files. If you want
33543 @file{configuration.scm} to be self-contained, we recommend that modules
33544 or files it refers to be part of a channel.
33546 Besides, provenance meta-data is ``silent'' in the sense that it does
33547 not change the bits contained in your system, @emph{except for the
33548 meta-data bits themselves}. Two different OS configurations or sets of
33549 channels can lead to the same system, bit-for-bit; when
33550 @code{provenance-service-type} is used, these two systems will have
33551 different meta-data and thus different store file names, which makes
33552 comparison less trivial.
33555 This service is automatically added to your operating system
33556 configuration when you use @command{guix system reconfigure},
33557 @command{guix system init}, or @command{guix deploy}.
33560 @node Shepherd Services
33561 @subsection Shepherd Services
33563 @cindex shepherd services
33565 @cindex init system
33566 The @code{(gnu services shepherd)} module provides a way to define
33567 services managed by the GNU@tie{}Shepherd, which is the
33568 initialization system---the first process that is started when the
33569 system boots, also known as PID@tie{}1
33570 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
33572 Services in the Shepherd can depend on each other. For instance, the
33573 SSH daemon may need to be started after the syslog daemon has been
33574 started, which in turn can only happen once all the file systems have
33575 been mounted. The simple operating system defined earlier (@pxref{Using
33576 the Configuration System}) results in a service graph like this:
33578 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
33580 You can actually generate such a graph for any operating system
33581 definition using the @command{guix system shepherd-graph} command
33582 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
33584 The @code{%shepherd-root-service} is a service object representing
33585 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
33586 by passing it lists of @code{<shepherd-service>} objects.
33588 @deftp {Data Type} shepherd-service
33589 The data type representing a service managed by the Shepherd.
33592 @item @code{provision}
33593 This is a list of symbols denoting what the service provides.
33595 These are the names that may be passed to @command{herd start},
33596 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
33597 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
33598 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
33600 @item @code{requirement} (default: @code{'()})
33601 List of symbols denoting the Shepherd services this one depends on.
33603 @cindex one-shot services, for the Shepherd
33604 @item @code{one-shot?} (default: @code{#f})
33605 Whether this service is @dfn{one-shot}. One-shot services stop immediately
33606 after their @code{start} action has completed. @xref{Slots of services,,,
33607 shepherd, The GNU Shepherd Manual}, for more info.
33609 @item @code{respawn?} (default: @code{#t})
33610 Whether to restart the service when it stops, for instance when the
33611 underlying process dies.
33614 @itemx @code{stop} (default: @code{#~(const #f)})
33615 The @code{start} and @code{stop} fields refer to the Shepherd's
33616 facilities to start and stop processes (@pxref{Service De- and
33617 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
33618 G-expressions that get expanded in the Shepherd configuration file
33619 (@pxref{G-Expressions}).
33621 @item @code{actions} (default: @code{'()})
33622 @cindex actions, of Shepherd services
33623 This is a list of @code{shepherd-action} objects (see below) defining
33624 @dfn{actions} supported by the service, in addition to the standard
33625 @code{start} and @code{stop} actions. Actions listed here become available as
33626 @command{herd} sub-commands:
33629 herd @var{action} @var{service} [@var{arguments}@dots{}]
33632 @item @code{auto-start?} (default: @code{#t})
33633 Whether this service should be started automatically by the Shepherd. If it
33634 is @code{#f} the service has to be started manually with @code{herd start}.
33636 @item @code{documentation}
33637 A documentation string, as shown when running:
33640 herd doc @var{service-name}
33643 where @var{service-name} is one of the symbols in @code{provision}
33644 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
33646 @item @code{modules} (default: @code{%default-modules})
33647 This is the list of modules that must be in scope when @code{start} and
33648 @code{stop} are evaluated.
33653 @deftp {Data Type} shepherd-action
33654 This is the data type that defines additional actions implemented by a
33655 Shepherd service (see above).
33659 Symbol naming the action.
33661 @item documentation
33662 This is a documentation string for the action. It can be viewed by running:
33665 herd doc @var{service} action @var{action}
33669 This should be a gexp that evaluates to a procedure of at least one argument,
33670 which is the ``running value'' of the service (@pxref{Slots of services,,,
33671 shepherd, The GNU Shepherd Manual}).
33674 The following example defines an action called @code{say-hello} that kindly
33680 (documentation "Say hi!")
33681 (procedure #~(lambda (running . args)
33682 (format #t "Hello, friend! arguments: ~s\n"
33687 Assuming this action is added to the @code{example} service, then you can do:
33690 # herd say-hello example
33691 Hello, friend! arguments: ()
33692 # herd say-hello example a b c
33693 Hello, friend! arguments: ("a" "b" "c")
33696 This, as you can see, is a fairly sophisticated way to say hello.
33697 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
33701 @defvr {Scheme Variable} shepherd-root-service-type
33702 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
33704 This is the service type that extensions target when they want to create
33705 shepherd services (@pxref{Service Types and Services}, for an example).
33706 Each extension must pass a list of @code{<shepherd-service>}. Its
33707 value must be a @code{shepherd-configuration}, as described below.
33710 @deftp {Data Type} shepherd-configuration
33711 This data type represents the Shepherd's configuration.
33714 @item shepherd (default: @code{shepherd})
33715 The Shepherd package to use.
33717 @item services (default: @code{'()})
33718 A list of @code{<shepherd-service>} to start.
33719 You should probably use the service extension
33720 mechanism instead (@pxref{Shepherd Services}).
33724 The following example specifies the Shepherd package for the operating
33730 (services (append (list openssh-service-type))
33734 ;; Use own Shepherd package.
33735 (essential-services
33736 (modify-services (operating-system-default-essential-services
33737 this-operating-system)
33738 (shepherd-root-service-type config => (shepherd-configuration
33740 (shepherd my-shepherd))))))
33743 @defvr {Scheme Variable} %shepherd-root-service
33744 This service represents PID@tie{}1.
33748 @node Documentation
33749 @chapter Documentation
33751 @cindex documentation, searching for
33752 @cindex searching for documentation
33753 @cindex Info, documentation format
33755 @cindex manual pages
33756 In most cases packages installed with Guix come with documentation.
33757 There are two main documentation formats: ``Info'', a browseable
33758 hypertext format used for GNU software, and ``manual pages'' (or ``man
33759 pages''), the linear documentation format traditionally found on Unix.
33760 Info manuals are accessed with the @command{info} command or with Emacs,
33761 and man pages are accessed using @command{man}.
33763 You can look for documentation of software installed on your system by
33764 keyword. For example, the following command searches for information
33765 about ``TLS'' in Info manuals:
33769 "(emacs)Network Security" -- STARTTLS
33770 "(emacs)Network Security" -- TLS
33771 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
33772 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
33777 The command below searches for the same keyword in man pages:
33781 SSL (7) - OpenSSL SSL/TLS library
33782 certtool (1) - GnuTLS certificate tool
33786 These searches are purely local to your computer so you have the
33787 guarantee that documentation you find corresponds to what you have
33788 actually installed, you can access it off-line, and your privacy is
33791 Once you have these results, you can view the relevant documentation by
33795 $ info "(gnutls)Core TLS API"
33805 Info manuals contain sections and indices as well as hyperlinks like
33806 those found in Web pages. The @command{info} reader (@pxref{Top, Info
33807 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
33808 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
33809 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
33810 Introduction}, for an introduction to Info navigation.
33812 @node Installing Debugging Files
33813 @chapter Installing Debugging Files
33815 @cindex debugging files
33816 Program binaries, as produced by the GCC compilers for instance, are
33817 typically written in the ELF format, with a section containing
33818 @dfn{debugging information}. Debugging information is what allows the
33819 debugger, GDB, to map binary code to source code; it is required to
33820 debug a compiled program in good conditions.
33822 This chapter explains how to use separate debug info when packages
33823 provide it, and how to rebuild packages with debug info when it's
33827 * Separate Debug Info:: Installing 'debug' outputs.
33828 * Rebuilding Debug Info:: Building missing debug info.
33831 @node Separate Debug Info
33832 @section Separate Debug Info
33834 The problem with debugging information is that is takes up a fair amount
33835 of disk space. For example, debugging information for the GNU C Library
33836 weighs in at more than 60 MiB@. Thus, as a user, keeping all the
33837 debugging info of all the installed programs is usually not an option.
33838 Yet, space savings should not come at the cost of an impediment to
33839 debugging---especially in the GNU system, which should make it easier
33840 for users to exert their computing freedom (@pxref{GNU Distribution}).
33842 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
33843 mechanism that allows users to get the best of both worlds: debugging
33844 information can be stripped from the binaries and stored in separate
33845 files. GDB is then able to load debugging information from those files,
33846 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
33849 The GNU distribution takes advantage of this by storing debugging
33850 information in the @code{lib/debug} sub-directory of a separate package
33851 output unimaginatively called @code{debug} (@pxref{Packages with
33852 Multiple Outputs}). Users can choose to install the @code{debug} output
33853 of a package when they need it. For instance, the following command
33854 installs the debugging information for the GNU C Library and for GNU
33858 guix install glibc:debug guile:debug
33861 GDB must then be told to look for debug files in the user's profile, by
33862 setting the @code{debug-file-directory} variable (consider setting it
33863 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
33867 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
33870 From there on, GDB will pick up debugging information from the
33871 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
33873 In addition, you will most likely want GDB to be able to show the source
33874 code being debugged. To do that, you will have to unpack the source
33875 code of the package of interest (obtained with @code{guix build
33876 --source}, @pxref{Invoking guix build}), and to point GDB to that source
33877 directory using the @code{directory} command (@pxref{Source Path,
33878 @code{directory},, gdb, Debugging with GDB}).
33880 @c XXX: keep me up-to-date
33881 The @code{debug} output mechanism in Guix is implemented by the
33882 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
33883 opt-in---debugging information is available only for the packages with
33884 definitions explicitly declaring a @code{debug} output. To check
33885 whether a package has a @code{debug} output, use @command{guix package
33886 --list-available} (@pxref{Invoking guix package}).
33888 Read on for how to deal with packages lacking a @code{debug} output.
33890 @node Rebuilding Debug Info
33891 @section Rebuilding Debug Info
33893 @cindex debugging info, rebuilding
33894 As we saw above, some packages, but not all, provide debugging info in a
33895 @code{debug} output. What can you do when debugging info is missing?
33896 The @option{--with-debug-info} option provides a solution to that: it
33897 allows you to rebuild the package(s) for which debugging info is
33898 missing---and only those---and to graft those onto the application
33899 you're debugging. Thus, while it's not as fast as installing a
33900 @code{debug} output, it is relatively inexpensive.
33902 Let's illustrate that. Suppose you're experiencing a bug in Inkscape
33903 and would like to see what's going on in GLib, a library that's deep
33904 down in its dependency graph. As it turns out, GLib does not have a
33905 @code{debug} output and the backtrace GDB shows is all sadness:
33909 #0 0x00007ffff5f92190 in g_getenv ()
33910 from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
33911 #1 0x00007ffff608a7d6 in gobject_init_ctor ()
33912 from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
33913 #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
33914 env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
33915 #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
33919 To address that, you install Inkscape linked against a variant GLib that
33920 contains debug info:
33923 guix install inkscape --with-debug-info=glib
33926 This time, debugging will be a whole lot nicer:
33929 $ gdb --args sh -c 'exec inkscape'
33932 Function "g_getenv" not defined.
33933 Make breakpoint pending on future shared library load? (y or [n]) y
33934 Breakpoint 1 (g_getenv) pending.
33936 Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
33939 #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
33940 #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
33941 #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
33942 #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
33943 env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
33949 Note that there can be packages for which @option{--with-debug-info}
33950 will not have the desired effect. @xref{Package Transformation Options,
33951 @option{--with-debug-info}}, for more information.
33953 @node Security Updates
33954 @chapter Security Updates
33956 @cindex security updates
33957 @cindex security vulnerabilities
33958 Occasionally, important security vulnerabilities are discovered in software
33959 packages and must be patched. Guix developers try hard to keep track of
33960 known vulnerabilities and to apply fixes as soon as possible in the
33961 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
33962 containing only security updates). The @command{guix lint} tool helps
33963 developers find out about vulnerable versions of software packages in the
33968 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
33969 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
33970 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
33974 @xref{Invoking guix lint}, for more information.
33976 Guix follows a functional
33977 package management discipline (@pxref{Introduction}), which implies
33978 that, when a package is changed, @emph{every package that depends on it}
33979 must be rebuilt. This can significantly slow down the deployment of
33980 fixes in core packages such as libc or Bash, since basically the whole
33981 distribution would need to be rebuilt. Using pre-built binaries helps
33982 (@pxref{Substitutes}), but deployment may still take more time than
33986 To address this, Guix implements @dfn{grafts}, a mechanism that allows
33987 for fast deployment of critical updates without the costs associated
33988 with a whole-distribution rebuild. The idea is to rebuild only the
33989 package that needs to be patched, and then to ``graft'' it onto packages
33990 explicitly installed by the user and that were previously referring to
33991 the original package. The cost of grafting is typically very low, and
33992 order of magnitudes lower than a full rebuild of the dependency chain.
33994 @cindex replacements of packages, for grafts
33995 For instance, suppose a security update needs to be applied to Bash.
33996 Guix developers will provide a package definition for the ``fixed''
33997 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
33998 Packages}). Then, the original package definition is augmented with a
33999 @code{replacement} field pointing to the package containing the bug fix:
34006 (replacement bash-fixed)))
34009 From there on, any package depending directly or indirectly on Bash---as
34010 reported by @command{guix gc --requisites} (@pxref{Invoking guix
34011 gc})---that is installed is automatically ``rewritten'' to refer to
34012 @code{bash-fixed} instead of @code{bash}. This grafting process takes
34013 time proportional to the size of the package, usually less than a
34014 minute for an ``average'' package on a recent machine. Grafting is
34015 recursive: when an indirect dependency requires grafting, then grafting
34016 ``propagates'' up to the package that the user is installing.
34018 Currently, the length of the name and version of the graft and that of
34019 the package it replaces (@code{bash-fixed} and @code{bash} in the example
34020 above) must be equal. This restriction mostly comes from the fact that
34021 grafting works by patching files, including binary files, directly.
34022 Other restrictions may apply: for instance, when adding a graft to a
34023 package providing a shared library, the original shared library and its
34024 replacement must have the same @code{SONAME} and be binary-compatible.
34026 The @option{--no-grafts} command-line option allows you to forcefully
34027 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
34031 guix build bash --no-grafts
34035 returns the store file name of the original Bash, whereas:
34042 returns the store file name of the ``fixed'', replacement Bash. This
34043 allows you to distinguish between the two variants of Bash.
34045 To verify which Bash your whole profile refers to, you can run
34046 (@pxref{Invoking guix gc}):
34049 guix gc -R `readlink -f ~/.guix-profile` | grep bash
34053 @dots{} and compare the store file names that you get with those above.
34054 Likewise for a complete Guix system generation:
34057 guix gc -R `guix system build my-config.scm` | grep bash
34060 Lastly, to check which Bash running processes are using, you can use the
34061 @command{lsof} command:
34064 lsof | grep /gnu/store/.*bash
34068 @node Bootstrapping
34069 @chapter Bootstrapping
34071 @c Adapted from the ELS 2013 paper.
34073 @cindex bootstrapping
34075 Bootstrapping in our context refers to how the distribution gets built
34076 ``from nothing''. Remember that the build environment of a derivation
34077 contains nothing but its declared inputs (@pxref{Introduction}). So
34078 there's an obvious chicken-and-egg problem: how does the first package
34079 get built? How does the first compiler get compiled?
34081 It is tempting to think of this question as one that only die-hard
34082 hackers may care about. However, while the answer to that question is
34083 technical in nature, its implications are wide-ranging. How the
34084 distribution is bootstrapped defines the extent to which we, as
34085 individuals and as a collective of users and hackers, can trust the
34086 software we run. It is a central concern from the standpoint of
34087 @emph{security} and from a @emph{user freedom} viewpoint.
34089 @cindex bootstrap binaries
34090 The GNU system is primarily made of C code, with libc at its core. The
34091 GNU build system itself assumes the availability of a Bourne shell and
34092 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
34093 `grep'. Furthermore, build programs---programs that run
34094 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
34095 (@pxref{Derivations}). Consequently, to be able to build anything at
34096 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
34097 Binutils, libc, and the other packages mentioned above---the
34098 @dfn{bootstrap binaries}.
34100 These bootstrap binaries are ``taken for granted'', though we can also
34101 re-create them if needed (@pxref{Preparing to Use the Bootstrap
34105 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
34106 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
34109 @node Reduced Binary Seed Bootstrap
34110 @section The Reduced Binary Seed Bootstrap
34112 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
34113 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
34114 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
34115 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
34116 ``taken for granted.''
34118 Taking the bootstrap binaries for granted means that we consider them to
34119 be a correct and trustworthy ``seed'' for building the complete system.
34120 Therein lies a problem: the combined size of these bootstrap binaries is
34121 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
34122 or even inspecting these is next to impossible.
34124 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
34125 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
34126 Source Bootstrap'' and while we are working towards that goal it would
34127 be hyperbole to use that term for what we do now.}.
34129 The Reduced Binary Seed bootstrap removes the most critical tools---from a
34130 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
34131 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
34132 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
34133 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
34135 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
34136 C Library are built from source. From here on the more traditional
34137 bootstrap process resumes. This approach has reduced the bootstrap
34138 binaries in size to about 145MB in Guix v1.1.
34140 The next step that Guix has taken is to replace the shell and all its
34141 utilities with implementations in Guile Scheme, the @emph{Scheme-only
34142 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
34143 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
34144 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
34145 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
34146 removed are now built from source.
34148 Building the GNU System from source is currently only possibly by adding
34149 some historical GNU packages as intermediate steps@footnote{Packages
34150 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
34151 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
34152 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
34153 and GNU packages become more bootstrappable again (e.g., new releases of
34154 GNU Sed will also ship as gzipped tarballs again, as alternative to the
34155 hard to bootstrap @code{xz}-compression), this set of added packages can
34156 hopefully be reduced again.
34158 The graph below shows the resulting dependency graph for
34159 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
34160 traditional bootstrap of the rest of the Guix System.
34162 @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
34163 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
34165 The only significant binary bootstrap seeds that remain@footnote{
34166 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
34167 together with @code{mes}.} are a Scheme intepreter and a Scheme
34168 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
34169 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
34170 to get Guile running.}.
34172 This further reduction has brought down the size of the binary seed to
34173 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
34175 Work is ongoing to remove all binary blobs from our free software
34176 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
34177 is work to bring these bootstraps to the @code{arm-linux} and
34178 @code{aarch64-linux} architectures and to the Hurd.
34180 If you are interested, join us on @samp{#bootstrappable} on the Freenode
34181 IRC network or discuss on @email{bug-mes@@gnu.org} or
34182 @email{gash-devel@@nongnu.org}.
34184 @node Preparing to Use the Bootstrap Binaries
34185 @section Preparing to Use the Bootstrap Binaries
34187 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
34188 @c large image, it's hard to scroll. Oh well.
34189 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
34191 The figure above shows the very beginning of the dependency graph of the
34192 distribution, corresponding to the package definitions of the @code{(gnu
34193 packages bootstrap)} module. A similar figure can be generated with
34194 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
34197 guix graph -t derivation \
34198 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
34199 | dot -Tps > gcc.ps
34202 or, for the further Reduced Binary Seed bootstrap
34205 guix graph -t derivation \
34206 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
34207 | dot -Tps > mes.ps
34210 At this level of detail, things are
34211 slightly complex. First, Guile itself consists of an ELF executable,
34212 along with many source and compiled Scheme files that are dynamically
34213 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
34214 tarball shown in this graph. This tarball is part of Guix's ``source''
34215 distribution, and gets inserted into the store with @code{add-to-store}
34216 (@pxref{The Store}).
34218 But how do we write a derivation that unpacks this tarball and adds it
34219 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
34220 derivation---the first one that gets built---uses @code{bash} as its
34221 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
34222 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
34223 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
34224 the Guix source distribution, whose sole purpose is to allow the Guile
34225 tarball to be unpacked.
34227 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
34228 Guile that can be used to run subsequent build programs. Its first task
34229 is to download tarballs containing the other pre-built binaries---this
34230 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
34231 @code{ftp-client.scm} are used for this purpose. The
34232 @code{module-import.drv} derivations import those modules in a directory
34233 in the store, using the original layout. The
34234 @code{module-import-compiled.drv} derivations compile those modules, and
34235 write them in an output directory with the right layout. This
34236 corresponds to the @code{#:modules} argument of
34237 @code{build-expression->derivation} (@pxref{Derivations}).
34239 Finally, the various tarballs are unpacked by the derivations
34240 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
34241 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
34242 point we have a working C tool chain.
34244 @unnumberedsec Building the Build Tools
34246 Bootstrapping is complete when we have a full tool chain that does not
34247 depend on the pre-built bootstrap tools discussed above. This
34248 no-dependency requirement is verified by checking whether the files of
34249 the final tool chain contain references to the @file{/gnu/store}
34250 directories of the bootstrap inputs. The process that leads to this
34251 ``final'' tool chain is described by the package definitions found in
34252 the @code{(gnu packages commencement)} module.
34254 The @command{guix graph} command allows us to ``zoom out'' compared to
34255 the graph above, by looking at the level of package objects instead of
34256 individual derivations---remember that a package may translate to
34257 several derivations, typically one derivation to download its source,
34258 one to build the Guile modules it needs, and one to actually build the
34259 package from source. The command:
34262 guix graph -t bag \
34263 -e '(@@@@ (gnu packages commencement)
34264 glibc-final-with-bootstrap-bash)' | xdot -
34268 displays the dependency graph leading to the ``final'' C
34269 library@footnote{You may notice the @code{glibc-intermediate} label,
34270 suggesting that it is not @emph{quite} final, but as a good
34271 approximation, we will consider it final.}, depicted below.
34273 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
34275 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
34276 The first tool that gets built with the bootstrap binaries is
34277 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
34278 for all the following packages. From there Findutils and Diffutils get
34281 Then come the first-stage Binutils and GCC, built as pseudo cross
34282 tools---i.e., with @option{--target} equal to @option{--host}. They are
34283 used to build libc. Thanks to this cross-build trick, this libc is
34284 guaranteed not to hold any reference to the initial tool chain.
34286 From there the final Binutils and GCC (not shown above) are built. GCC
34287 uses @command{ld} from the final Binutils, and links programs against
34288 the just-built libc. This tool chain is used to build the other
34289 packages used by Guix and by the GNU Build System: Guile, Bash,
34292 And voilà! At this point we have the complete set of build tools that
34293 the GNU Build System expects. These are in the @code{%final-inputs}
34294 variable of the @code{(gnu packages commencement)} module, and are
34295 implicitly used by any package that uses @code{gnu-build-system}
34296 (@pxref{Build Systems, @code{gnu-build-system}}).
34299 @unnumberedsec Building the Bootstrap Binaries
34301 @cindex bootstrap binaries
34302 Because the final tool chain does not depend on the bootstrap binaries,
34303 those rarely need to be updated. Nevertheless, it is useful to have an
34304 automated way to produce them, should an update occur, and this is what
34305 the @code{(gnu packages make-bootstrap)} module provides.
34307 The following command builds the tarballs containing the bootstrap binaries
34308 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
34309 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
34310 and Guile, and a tarball containing a mixture of Coreutils and other basic
34311 command-line tools):
34314 guix build bootstrap-tarballs
34317 The generated tarballs are those that should be referred to in the
34318 @code{(gnu packages bootstrap)} module mentioned at the beginning of
34321 Still here? Then perhaps by now you've started to wonder: when do we
34322 reach a fixed point? That is an interesting question! The answer is
34323 unknown, but if you would like to investigate further (and have
34324 significant computational and storage resources to do so), then let us
34327 @unnumberedsec Reducing the Set of Bootstrap Binaries
34329 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
34330 binary code! Why is that a problem? It's a problem because these big chunks
34331 of binary code are practically non-auditable, which makes it hard to establish
34332 what source code produced them. Every unauditable binary also leaves us
34333 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
34334 paper @emph{Reflections on Trusting Trust}.
34336 This is mitigated by the fact that our bootstrap binaries were generated
34337 from an earlier Guix revision. Nevertheless it lacks the level of
34338 transparency that we get in the rest of the package dependency graph,
34339 where Guix always gives us a source-to-binary mapping. Thus, our goal
34340 is to reduce the set of bootstrap binaries to the bare minimum.
34342 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
34343 on-going projects to do that. One of these is about replacing the
34344 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
34345 of increasing complexity, which could be built from source starting from
34346 a simple and auditable assembler.
34348 Our first major achievement is the replacement of of GCC, the GNU C Library
34349 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
34350 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
34351 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
34352 bootstrapped yet and thus we inject them as binary seeds. We call this the
34353 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
34354 binaries! Also, it has eliminated the C compiler binary; i686-linux and
34355 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
34357 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
34358 also looking at any other bootstrap binaries. Your help is welcome!
34361 @chapter Porting to a New Platform
34363 As discussed above, the GNU distribution is self-contained, and
34364 self-containment is achieved by relying on pre-built ``bootstrap
34365 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
34366 operating system kernel, CPU architecture, and application binary
34367 interface (ABI). Thus, to port the distribution to a platform that is
34368 not yet supported, one must build those bootstrap binaries, and update
34369 the @code{(gnu packages bootstrap)} module to use them on that platform.
34371 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
34372 When everything goes well, and assuming the GNU tool chain supports the
34373 target platform, this can be as simple as running a command like this
34377 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
34380 For this to work, the @code{glibc-dynamic-linker} procedure in
34381 @code{(gnu packages bootstrap)} must be augmented to return the right
34382 file name for libc's dynamic linker on that platform; likewise,
34383 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
34384 taught about the new platform.
34386 Once these are built, the @code{(gnu packages bootstrap)} module needs
34387 to be updated to refer to these binaries on the target platform. That
34388 is, the hashes and URLs of the bootstrap tarballs for the new platform
34389 must be added alongside those of the currently supported platforms. The
34390 bootstrap Guile tarball is treated specially: it is expected to be
34391 available locally, and @file{gnu/local.mk} has rules to download it for
34392 the supported architectures; a rule for the new platform must be added
34395 In practice, there may be some complications. First, it may be that the
34396 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
34397 above) is not recognized by all the GNU tools. Typically, glibc
34398 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
34399 configure flag (see @code{gcc.scm} for examples of how to handle this).
34400 Second, some of the required packages could fail to build for that
34401 platform. Lastly, the generated binaries could be broken for some
34404 @c *********************************************************************
34405 @include contributing.texi
34407 @c *********************************************************************
34408 @node Acknowledgments
34409 @chapter Acknowledgments
34411 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
34412 which was designed and
34413 implemented by Eelco Dolstra, with contributions from other people (see
34414 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
34415 management, and promoted unprecedented features, such as transactional
34416 package upgrades and rollbacks, per-user profiles, and referentially
34417 transparent build processes. Without this work, Guix would not exist.
34419 The Nix-based software distributions, Nixpkgs and NixOS, have also been
34420 an inspiration for Guix.
34422 GNU@tie{}Guix itself is a collective work with contributions from a
34423 number of people. See the @file{AUTHORS} file in Guix for more
34424 information on these fine people. The @file{THANKS} file lists people
34425 who have helped by reporting bugs, taking care of the infrastructure,
34426 providing artwork and themes, making suggestions, and more---thank you!
34429 @c *********************************************************************
34430 @node GNU Free Documentation License
34431 @appendix GNU Free Documentation License
34432 @cindex license, GNU Free Documentation License
34433 @include fdl-1.3.texi
34435 @c *********************************************************************
34436 @node Concept Index
34437 @unnumbered Concept Index
34440 @node Programming Index
34441 @unnumbered Programming Index
34442 @syncodeindex tp fn
34443 @syncodeindex vr fn
34448 @c Local Variables:
34449 @c ispell-local-dictionary: "american";