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 27D586A4F8900854329FF09F1260E46482E63562
14 @set OPENPGP-SIGNING-KEY-URL https://sv.gnu.org/people/viewgpg.php?user_id=127547
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-1 ci.guix.gnu.org
21 @set SUBSTITUTE-SERVER-2 bordeaux.guix.gnu.org
22 @set SUBSTITUTE-URLS https://@value{SUBSTITUTE-SERVER-1} https://@value{SUBSTITUTE-SERVER-2}
25 Copyright @copyright{} 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 Ludovic Courtès@*
26 Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
27 Copyright @copyright{} 2013 Nikita Karetnikov@*
28 Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
29 Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
30 Copyright @copyright{} 2014 Pierre-Antoine Rault@*
31 Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
32 Copyright @copyright{} 2015, 2016, 2017, 2019, 2020, 2021 Leo Famulari@*
33 Copyright @copyright{} 2015, 2016, 2017, 2018, 2019, 2020 Ricardo Wurmus@*
34 Copyright @copyright{} 2016 Ben Woodcroft@*
35 Copyright @copyright{} 2016, 2017, 2018, 2021 Chris Marusich@*
36 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020, 2021 Efraim Flashner@*
37 Copyright @copyright{} 2016 John Darrington@*
38 Copyright @copyright{} 2016, 2017 Nikita Gillmann@*
39 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Jan Nieuwenhuizen@*
40 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020, 2021 Julien Lepiller@*
41 Copyright @copyright{} 2016 Alex ter Weele@*
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44 Copyright @copyright{} 2017, 2018, 2020, 2021 Mathieu Othacehe@*
45 Copyright @copyright{} 2017 Federico Beffa@*
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48 Copyright @copyright{} 2017 humanitiesNerd@*
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50 Copyright @copyright{} 2017, 2018, 2019, 2020 Marius Bakke@*
51 Copyright @copyright{} 2017, 2019, 2020 Hartmut Goebel@*
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53 Copyright @copyright{} 2017, 2018, 2019, 2020, 2021 Tobias Geerinckx-Rice@*
54 Copyright @copyright{} 2017 George Clemmer@*
55 Copyright @copyright{} 2017 Andy Wingo@*
56 Copyright @copyright{} 2017, 2018, 2019, 2020 Arun Isaac@*
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60 Copyright @copyright{} 2018 Mike Gerwitz@*
61 Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
62 Copyright @copyright{} 2018, 2019 Gábor Boskovits@*
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68 Copyright @copyright{} 2019 Ivan Petkov@*
69 Copyright @copyright{} 2019 Jakob L. Kreuze@*
70 Copyright @copyright{} 2019 Kyle Andrews@*
71 Copyright @copyright{} 2019 Alex Griffin@*
72 Copyright @copyright{} 2019, 2020, 2021 Guillaume Le Vaillant@*
73 Copyright @copyright{} 2020 Leo Prikler@*
74 Copyright @copyright{} 2019, 2020 Simon Tournier@*
75 Copyright @copyright{} 2020 Wiktor Żelazny@*
76 Copyright @copyright{} 2020 Damien Cassou@*
77 Copyright @copyright{} 2020 Jakub Kądziołka@*
78 Copyright @copyright{} 2020 Jack Hill@*
79 Copyright @copyright{} 2020 Naga Malleswari@*
80 Copyright @copyright{} 2020, 2021 Brice Waegeneire@*
81 Copyright @copyright{} 2020 R Veera Kumar@*
82 Copyright @copyright{} 2020 Pierre Langlois@*
83 Copyright @copyright{} 2020 pinoaffe@*
84 Copyright @copyright{} 2020 André Batista@*
85 Copyright @copyright{} 2020, 2021 Alexandru-Sergiu Marton@*
86 Copyright @copyright{} 2020 raingloom@*
87 Copyright @copyright{} 2020 Daniel Brooks@*
88 Copyright @copyright{} 2020 John Soo@*
89 Copyright @copyright{} 2020 Jonathan Brielmaier@*
90 Copyright @copyright{} 2020 Edgar Vincent@*
91 Copyright @copyright{} 2021 Maxime Devos@*
92 Copyright @copyright{} 2021 B. Wilson@*
93 Copyright @copyright{} 2021 Xinglu Chen@*
95 Permission is granted to copy, distribute and/or modify this document
96 under the terms of the GNU Free Documentation License, Version 1.3 or
97 any later version published by the Free Software Foundation; with no
98 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
99 copy of the license is included in the section entitled ``GNU Free
100 Documentation License''.
103 @dircategory System administration
105 * Guix: (guix). Manage installed software and system configuration.
106 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
107 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
108 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
109 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
110 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
113 @dircategory Software development
115 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
116 * guix build: (guix)Invoking guix build. Building packages.
117 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
121 @title GNU Guix Reference Manual
122 @subtitle Using the GNU Guix Functional Package Manager
123 @author The GNU Guix Developers
126 @vskip 0pt plus 1filll
127 Edition @value{EDITION} @*
135 @c *********************************************************************
139 This document describes GNU Guix version @value{VERSION}, a functional
140 package management tool written for the GNU system.
142 @c TRANSLATORS: You can replace the following paragraph with information on
143 @c how to join your own translation team and how to report issues with the
145 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
146 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
147 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
148 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
149 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
150 would like to translate it in your native language, consider joining
151 @uref{https://translate.fedoraproject.org/projects/guix/documentation-manual,
152 Weblate} (@pxref{Translating Guix}).
155 * Introduction:: What is Guix about?
156 * Installation:: Installing Guix.
157 * System Installation:: Installing the whole operating system.
158 * Getting Started:: Your first steps.
159 * Package Management:: Package installation, upgrade, etc.
160 * Channels:: Customizing the package collection.
161 * Development:: Guix-aided software development.
162 * Programming Interface:: Using Guix in Scheme.
163 * Utilities:: Package management commands.
164 * System Configuration:: Configuring the operating system.
165 * Documentation:: Browsing software user manuals.
166 * Installing Debugging Files:: Feeding the debugger.
167 * Security Updates:: Deploying security fixes quickly.
168 * Bootstrapping:: GNU/Linux built from scratch.
169 * Porting:: Targeting another platform or kernel.
170 * Contributing:: Your help needed!
172 * Acknowledgments:: Thanks!
173 * GNU Free Documentation License:: The license of this manual.
174 * Concept Index:: Concepts.
175 * Programming Index:: Data types, functions, and variables.
178 --- The Detailed Node Listing ---
182 * Managing Software the Guix Way:: What's special.
183 * GNU Distribution:: The packages and tools.
187 * Binary Installation:: Getting Guix running in no time!
188 * Requirements:: Software needed to build and run Guix.
189 * Running the Test Suite:: Testing Guix.
190 * Setting Up the Daemon:: Preparing the build daemon's environment.
191 * Invoking guix-daemon:: Running the build daemon.
192 * Application Setup:: Application-specific setup.
193 * Upgrading Guix:: Upgrading Guix and its build daemon.
195 Setting Up the Daemon
197 * Build Environment Setup:: Preparing the isolated build environment.
198 * Daemon Offload Setup:: Offloading builds to remote machines.
199 * SELinux Support:: Using an SELinux policy for the daemon.
203 * Limitations:: What you can expect.
204 * Hardware Considerations:: Supported hardware.
205 * USB Stick and DVD Installation:: Preparing the installation medium.
206 * Preparing for Installation:: Networking, partitioning, etc.
207 * Guided Graphical Installation:: Easy graphical installation.
208 * Manual Installation:: Manual installation for wizards.
209 * After System Installation:: When installation succeeded.
210 * Installing Guix in a VM:: Guix System playground.
211 * Building the Installation Image:: How this comes to be.
215 * Keyboard Layout and Networking and Partitioning:: Initial setup.
216 * Proceeding with the Installation:: Installing.
220 * Features:: How Guix will make your life brighter.
221 * Invoking guix package:: Package installation, removal, etc.
222 * Substitutes:: Downloading pre-built binaries.
223 * Packages with Multiple Outputs:: Single source package, multiple outputs.
224 * Invoking guix gc:: Running the garbage collector.
225 * Invoking guix pull:: Fetching the latest Guix and distribution.
226 * Invoking guix time-machine:: Running an older revision of Guix.
227 * Inferiors:: Interacting with another revision of Guix.
228 * Invoking guix describe:: Display information about your Guix revision.
229 * Invoking guix archive:: Exporting and importing store files.
233 * Official Substitute Servers:: One particular source of substitutes.
234 * Substitute Server Authorization:: How to enable or disable substitutes.
235 * Getting Substitutes from Other Servers:: Substitute diversity.
236 * Substitute Authentication:: How Guix verifies substitutes.
237 * Proxy Settings:: How to get substitutes via proxy.
238 * Substitution Failure:: What happens when substitution fails.
239 * On Trusting Binaries:: How can you trust that binary blob?
243 * Specifying Additional Channels:: Extending the package collection.
244 * Using a Custom Guix Channel:: Using a customized Guix.
245 * Replicating Guix:: Running the @emph{exact same} Guix.
246 * Channel Authentication:: How Guix verifies what it fetches.
247 * Channels with Substitutes:: Using channels with available substitutes.
248 * Creating a Channel:: How to write your custom channel.
249 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
250 * Declaring Channel Dependencies:: How to depend on other channels.
251 * Specifying Channel Authorizations:: Defining channel authors authorizations.
252 * Primary URL:: Distinguishing mirror to original.
253 * Writing Channel News:: Communicating information to channel's users.
257 * Invoking guix environment:: Setting up development environments.
258 * Invoking guix pack:: Creating software bundles.
259 * The GCC toolchain:: Working with languages supported by GCC.
260 * Invoking guix git authenticate:: Authenticating Git repositories.
262 Programming Interface
264 * Package Modules:: Packages from the programmer's viewpoint.
265 * Defining Packages:: Defining new packages.
266 * Defining Package Variants:: Customizing packages.
267 * Build Systems:: Specifying how packages are built.
268 * Build Phases:: Phases of the build process of a package.
269 * Build Utilities:: Helpers for your package definitions and more.
270 * The Store:: Manipulating the package store.
271 * Derivations:: Low-level interface to package derivations.
272 * The Store Monad:: Purely functional interface to the store.
273 * G-Expressions:: Manipulating build expressions.
274 * Invoking guix repl:: Programming Guix in Guile.
278 * package Reference:: The package data type.
279 * origin Reference:: The origin data type.
283 * Invoking guix build:: Building packages from the command line.
284 * Invoking guix edit:: Editing package definitions.
285 * Invoking guix download:: Downloading a file and printing its hash.
286 * Invoking guix hash:: Computing the cryptographic hash of a file.
287 * Invoking guix import:: Importing package definitions.
288 * Invoking guix refresh:: Updating package definitions.
289 * Invoking guix lint:: Finding errors in package definitions.
290 * Invoking guix size:: Profiling disk usage.
291 * Invoking guix graph:: Visualizing the graph of packages.
292 * Invoking guix publish:: Sharing substitutes.
293 * Invoking guix challenge:: Challenging substitute servers.
294 * Invoking guix copy:: Copying to and from a remote store.
295 * Invoking guix container:: Process isolation.
296 * Invoking guix weather:: Assessing substitute availability.
297 * Invoking guix processes:: Listing client processes.
299 Invoking @command{guix build}
301 * Common Build Options:: Build options for most commands.
302 * Package Transformation Options:: Creating variants of packages.
303 * Additional Build Options:: Options specific to 'guix build'.
304 * Debugging Build Failures:: Real life packaging experience.
308 * Using the Configuration System:: Customizing your GNU system.
309 * operating-system Reference:: Detail of operating-system declarations.
310 * File Systems:: Configuring file system mounts.
311 * Mapped Devices:: Block device extra processing.
312 * User Accounts:: Specifying user accounts.
313 * Keyboard Layout:: How the system interprets key strokes.
314 * Locales:: Language and cultural convention settings.
315 * Services:: Specifying system services.
316 * Setuid Programs:: Programs running with root privileges.
317 * X.509 Certificates:: Authenticating HTTPS servers.
318 * Name Service Switch:: Configuring libc's name service switch.
319 * Initial RAM Disk:: Linux-Libre bootstrapping.
320 * Bootloader Configuration:: Configuring the boot loader.
321 * Invoking guix system:: Instantiating a system configuration.
322 * Invoking guix deploy:: Deploying a system configuration to a remote host.
323 * Running Guix in a VM:: How to run Guix System in a virtual machine.
324 * Defining Services:: Adding new service definitions.
328 * Base Services:: Essential system services.
329 * Scheduled Job Execution:: The mcron service.
330 * Log Rotation:: The rottlog service.
331 * Networking Services:: Network setup, SSH daemon, etc.
332 * Unattended Upgrades:: Automated system upgrades.
333 * X Window:: Graphical display.
334 * Printing Services:: Local and remote printer support.
335 * Desktop Services:: D-Bus and desktop services.
336 * Sound Services:: ALSA and Pulseaudio services.
337 * Database Services:: SQL databases, key-value stores, etc.
338 * Mail Services:: IMAP, POP3, SMTP, and all that.
339 * Messaging Services:: Messaging services.
340 * Telephony Services:: Telephony services.
341 * Monitoring Services:: Monitoring services.
342 * Kerberos Services:: Kerberos services.
343 * LDAP Services:: LDAP services.
344 * Web Services:: Web servers.
345 * Certificate Services:: TLS certificates via Let's Encrypt.
346 * DNS Services:: DNS daemons.
347 * VPN Services:: VPN daemons.
348 * Network File System:: NFS related services.
349 * Continuous Integration:: Cuirass and Laminar services.
350 * Power Management Services:: Extending battery life.
351 * Audio Services:: The MPD.
352 * Virtualization Services:: Virtualization services.
353 * Version Control Services:: Providing remote access to Git repositories.
354 * Game Services:: Game servers.
355 * PAM Mount Service:: Service to mount volumes when logging in.
356 * Guix Services:: Services relating specifically to Guix.
357 * Linux Services:: Services tied to the Linux kernel.
358 * Hurd Services:: Services specific for a Hurd System.
359 * Miscellaneous Services:: Other services.
363 * Service Composition:: The model for composing services.
364 * Service Types and Services:: Types and services.
365 * Service Reference:: API reference.
366 * Shepherd Services:: A particular type of service.
368 Installing Debugging Files
370 * Separate Debug Info:: Installing 'debug' outputs.
371 * Rebuilding Debug Info:: Building missing debug info.
375 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
376 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
381 @c *********************************************************************
383 @chapter Introduction
386 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
387 using the international phonetic alphabet (IPA).} is a package
388 management tool for and distribution of the GNU system.
389 Guix makes it easy for unprivileged
390 users to install, upgrade, or remove software packages, to roll back to a
391 previous package set, to build packages from source, and generally
392 assists with the creation and maintenance of software environments.
395 @cindex GuixSD, now Guix System
396 @cindex Guix System Distribution, now Guix System
397 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
398 complements the available tools without interference (@pxref{Installation}),
399 or you can use it as a standalone operating system distribution,
400 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
401 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
402 group everything under the ``Guix'' banner since, after all, Guix System is
403 readily available through the @command{guix system} command, even if you're
404 using a different distro underneath!}. @xref{GNU Distribution}.
407 * Managing Software the Guix Way:: What's special.
408 * GNU Distribution:: The packages and tools.
411 @node Managing Software the Guix Way
412 @section Managing Software the Guix Way
414 @cindex user interfaces
415 Guix provides a command-line package management interface
416 (@pxref{Package Management}), tools to help with software development
417 (@pxref{Development}), command-line utilities for more advanced usage
418 (@pxref{Utilities}), as well as Scheme programming interfaces
419 (@pxref{Programming Interface}).
421 Its @dfn{build daemon} is responsible for building packages on behalf of
422 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
423 binaries from authorized sources (@pxref{Substitutes}).
425 @cindex extensibility of the distribution
426 @cindex customization, of packages
427 Guix includes package definitions for many GNU and non-GNU packages, all
428 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
429 user's computing freedom}. It is @emph{extensible}: users can write
430 their own package definitions (@pxref{Defining Packages}) and make them
431 available as independent package modules (@pxref{Package Modules}). It
432 is also @emph{customizable}: users can @emph{derive} specialized package
433 definitions from existing ones, including from the command line
434 (@pxref{Package Transformation Options}).
436 @cindex functional package management
438 Under the hood, Guix implements the @dfn{functional package management}
439 discipline pioneered by Nix (@pxref{Acknowledgments}).
440 In Guix, the package build and installation process is seen
441 as a @emph{function}, in the mathematical sense. That function takes inputs,
442 such as build scripts, a compiler, and libraries, and
443 returns an installed package. As a pure function, its result depends
444 solely on its inputs---for instance, it cannot refer to software or
445 scripts that were not explicitly passed as inputs. A build function
446 always produces the same result when passed a given set of inputs. It
447 cannot alter the environment of the running system in
448 any way; for instance, it cannot create, modify, or delete files outside
449 of its build and installation directories. This is achieved by running
450 build processes in isolated environments (or @dfn{containers}), where only their
451 explicit inputs are visible.
454 The result of package build functions is @dfn{cached} in the file
455 system, in a special directory called @dfn{the store} (@pxref{The
456 Store}). Each package is installed in a directory of its own in the
457 store---by default under @file{/gnu/store}. The directory name contains
458 a hash of all the inputs used to build that package; thus, changing an
459 input yields a different directory name.
461 This approach is the foundation for the salient features of Guix: support
462 for transactional package upgrade and rollback, per-user installation, and
463 garbage collection of packages (@pxref{Features}).
466 @node GNU Distribution
467 @section GNU Distribution
470 Guix comes with a distribution of the GNU system consisting entirely of
471 free software@footnote{The term ``free'' here refers to the
472 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
473 users of that software}.}. The
474 distribution can be installed on its own (@pxref{System Installation}),
475 but it is also possible to install Guix as a package manager on top of
476 an installed GNU/Linux system (@pxref{Installation}). When we need to
477 distinguish between the two, we refer to the standalone distribution as
480 The distribution provides core GNU packages such as GNU libc, GCC, and
481 Binutils, as well as many GNU and non-GNU applications. The complete
482 list of available packages can be browsed
483 @url{https://www.gnu.org/software/guix/packages,on-line} or by
484 running @command{guix package} (@pxref{Invoking guix package}):
487 guix package --list-available
490 Our goal is to provide a practical 100% free software distribution of
491 Linux-based and other variants of GNU, with a focus on the promotion and
492 tight integration of GNU components, and an emphasis on programs and
493 tools that help users exert that freedom.
495 Packages are currently available on the following platforms:
500 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel.
503 Intel 32-bit architecture (IA32), Linux-Libre kernel.
506 ARMv7-A architecture with hard float, Thumb-2 and NEON,
507 using the EABI hard-float application binary interface (ABI),
508 and Linux-Libre kernel.
511 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
514 @uref{https://hurd.gnu.org, GNU/Hurd} on the Intel 32-bit architecture
517 This configuration is experimental and under development. The easiest
518 way for you to give it a try is by setting up an instance of
519 @code{hurd-vm-service-type} on your GNU/Linux machine
520 (@pxref{transparent-emulation-qemu, @code{hurd-vm-service-type}}).
521 @xref{Contributing}, on how to help!
523 @item mips64el-linux (deprecated)
524 little-endian 64-bit MIPS processors, specifically the Loongson series,
525 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
526 supported; in particular, there is no ongoing work to ensure that this
527 architecture still works. Should someone decide they wish to revive this
528 architecture then the code is still available.
530 @item powerpc64le-linux
531 little-endian 64-bit Power ISA processors, Linux-Libre kernel. This
532 includes POWER9 systems such as the
533 @uref{https://www.fsf.org/news/talos-ii-mainboard-and-talos-ii-lite-mainboard-now-fsf-certified-to-respect-your-freedom,
534 RYF Talos II mainboard}. This platform is available as a "technology
535 preview": although it is supported, substitutes are not yet available
536 from the build farm (@pxref{Substitutes}), and some packages may fail to
537 build (@pxref{Tracking Bugs and Patches}). That said, the Guix
538 community is actively working on improving this support, and now is a
539 great time to try it and get involved!
543 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
544 configuration and Guix takes care of instantiating the configuration in a
545 transactional, reproducible, and stateless fashion (@pxref{System
546 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
547 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
548 Manual}), the well-known GNU utilities and tool chain, as well as the
549 graphical environment or system services of your choice.
551 Guix System is available on all the above platforms except
552 @code{mips64el-linux} and @code{powerpc64le-linux}.
555 For information on porting to other architectures or kernels,
558 Building this distribution is a cooperative effort, and you are invited
559 to join! @xref{Contributing}, for information about how you can help.
562 @c *********************************************************************
564 @chapter Installation
566 @cindex installing Guix
569 We recommend the use of this
570 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
571 shell installer script} to install Guix on top of a running GNU/Linux system,
572 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
573 with the installation of the package manager, which can be done on top of a
574 running GNU/Linux system. If, instead, you want to install the complete GNU
575 operating system, @pxref{System Installation}.} The script automates the
576 download, installation, and initial configuration of Guix. It should be run
580 @cindex foreign distro
581 @cindex directories related to foreign distro
582 When installed on a foreign distro, GNU@tie{}Guix complements the available
583 tools without interference. Its data lives exclusively in two directories,
584 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
585 such as @file{/etc}, are left untouched.
587 Once installed, Guix can be updated by running @command{guix pull}
588 (@pxref{Invoking guix pull}).
590 If you prefer to perform the installation steps manually or want to tweak
591 them, you may find the following subsections useful. They describe the
592 software requirements of Guix, as well as how to install it manually and get
596 * Binary Installation:: Getting Guix running in no time!
597 * Requirements:: Software needed to build and run Guix.
598 * Running the Test Suite:: Testing Guix.
599 * Setting Up the Daemon:: Preparing the build daemon's environment.
600 * Invoking guix-daemon:: Running the build daemon.
601 * Application Setup:: Application-specific setup.
602 * Upgrading Guix:: Upgrading Guix and its build daemon.
605 @node Binary Installation
606 @section Binary Installation
608 @cindex installing Guix from binaries
609 @cindex installer script
610 This section describes how to install Guix on an arbitrary system from a
611 self-contained tarball providing binaries for Guix and for all its
612 dependencies. This is often quicker than installing from source, which
613 is described in the next sections. The only requirement is to have
616 @c Note duplicated from the ``Installation'' node.
618 We recommend the use of this
619 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
620 shell installer script}. The script automates the download, installation, and
621 initial configuration steps described below. It should be run as the root
622 user. As root, you can thus run this:
626 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
627 chmod +x guix-install.sh
631 When you're done, @pxref{Application Setup} for extra configuration you
632 might need, and @ref{Getting Started} for your first steps!
635 Installing goes along these lines:
639 @cindex downloading Guix binary
640 Download the binary tarball from
641 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
642 where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
643 @code{i686} (32-bits) machine already running the kernel Linux, and so on
644 (@pxref{GNU Distribution}).
646 @c The following is somewhat duplicated in ``System Installation''.
647 Make sure to download the associated @file{.sig} file and to verify the
648 authenticity of the tarball against it, along these lines:
651 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
652 $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
655 If that command fails because you do not have the required public key,
656 then run this command to import it:
659 $ wget '@value{OPENPGP-SIGNING-KEY-URL}' \
660 -qO - | gpg --import -
664 and rerun the @code{gpg --verify} command.
666 Take note that a warning like ``This key is not certified with a trusted
667 signature!'' is normal.
669 @c end authentication part
672 Now, you need to become the @code{root} user. Depending on your distribution,
673 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
677 # tar --warning=no-timestamp -xf \
678 /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
679 # mv var/guix /var/ && mv gnu /
682 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
683 The latter contains a ready-to-use profile for @code{root} (see next
686 Do @emph{not} unpack the tarball on a working Guix system since that
687 would overwrite its own essential files.
689 The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
690 not emit warnings about ``implausibly old time stamps'' (such
691 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
693 They stem from the fact that all the
694 files in the archive have their modification time set to 1 (which
695 means January 1st, 1970). This is done on purpose to make sure the
696 archive content is independent of its creation time, thus making it
700 Make the profile available under @file{~root/.config/guix/current}, which is
701 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
704 # mkdir -p ~root/.config/guix
705 # ln -sf /var/guix/profiles/per-user/root/current-guix \
706 ~root/.config/guix/current
709 Source @file{etc/profile} to augment @env{PATH} and other relevant
710 environment variables:
713 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
714 source $GUIX_PROFILE/etc/profile
718 Create the group and user accounts for build users as explained below
719 (@pxref{Build Environment Setup}).
722 Run the daemon, and set it to automatically start on boot.
724 If your host distro uses the systemd init system, this can be achieved
727 @c Versions of systemd that supported symlinked service files are not
728 @c yet widely deployed, so we should suggest that users copy the service
731 @c See this thread for more information:
732 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
735 # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
736 ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
738 # systemctl enable --now gnu-store.mount guix-daemon
741 If your host distro uses the Upstart init system:
744 # initctl reload-configuration
745 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
750 Otherwise, you can still start the daemon manually with:
753 # ~root/.config/guix/current/bin/guix-daemon \
754 --build-users-group=guixbuild
758 Make the @command{guix} command available to other users on the machine,
762 # mkdir -p /usr/local/bin
764 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
767 It is also a good idea to make the Info version of this manual available
771 # mkdir -p /usr/local/share/info
772 # cd /usr/local/share/info
773 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
777 That way, assuming @file{/usr/local/share/info} is in the search path,
778 running @command{info guix} will open this manual (@pxref{Other Info
779 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
783 @cindex substitutes, authorization thereof
784 To use substitutes from @code{@value{SUBSTITUTE-SERVER-1}},
785 @code{@value{SUBSTITUTE-SERVER-2}} or a mirror (@pxref{Substitutes}),
789 # guix archive --authorize < \
790 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
791 # guix archive --authorize < \
792 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
796 If you do not enable substitutes, Guix will end up building
797 @emph{everything} from source on your machine, making each installation
798 and upgrade very expensive. @xref{On Trusting Binaries}, for a
799 discussion of reasons why one might want do disable substitutes.
803 Each user may need to perform a few additional steps to make their Guix
804 environment ready for use, @pxref{Application Setup}.
807 Voilà, the installation is complete!
809 You can confirm that Guix is working by installing a sample package into
816 The binary installation tarball can be (re)produced and verified simply
817 by running the following command in the Guix source tree:
820 make guix-binary.@var{system}.tar.xz
824 ...@: which, in turn, runs:
827 guix pack -s @var{system} --localstatedir \
828 --profile-name=current-guix guix
831 @xref{Invoking guix pack}, for more info on this handy tool.
834 @section Requirements
836 This section lists requirements when building Guix from source. The
837 build procedure for Guix is the same as for other GNU software, and is
838 not covered here. Please see the files @file{README} and @file{INSTALL}
839 in the Guix source tree for additional details.
841 @cindex official website
842 GNU Guix is available for download from its website at
843 @url{https://www.gnu.org/software/guix/}.
845 GNU Guix depends on the following packages:
848 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x;
849 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
852 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
853 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
854 Guile,, gnutls-guile, GnuTLS-Guile});
856 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
858 @item @uref{https://notabug.org/guile-zlib/guile-zlib, Guile-zlib},
859 version 0.1.0 or later;
860 @item @uref{https://notabug.org/guile-lzlib/guile-lzlib, Guile-lzlib};
861 @item @uref{https://www.nongnu.org/guile-avahi/, Guile-Avahi};
863 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, version 0.5.0
865 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON}
867 @item @url{https://www.gnu.org/software/make/, GNU Make}.
870 The following dependencies are optional:
874 @c Note: We need at least 0.13.0 for #:nodelay.
875 Support for build offloading (@pxref{Daemon Offload Setup}) and
876 @command{guix copy} (@pxref{Invoking guix copy}) depends on
877 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
878 version 0.13.0 or later.
881 @uref{https://notabug.org/guile-zstd/guile-zstd, Guile-zstd}, for zstd
882 compression and decompression in @command{guix publish} and for
883 substitutes (@pxref{Invoking guix publish}).
886 @uref{https://ngyro.com/software/guile-semver.html, Guile-Semver} for
887 the @code{crate} importer (@pxref{Invoking guix import}).
890 @uref{https://www.nongnu.org/guile-lib/doc/ref/htmlprag/, Guile-Lib} for
891 the @code{go} importer (@pxref{Invoking guix import}) and for some of
892 the ``updaters'' (@pxref{Invoking guix refresh}).
895 When @url{http://www.bzip.org, libbz2} is available,
896 @command{guix-daemon} can use it to compress build logs.
899 Unless @option{--disable-daemon} was passed to @command{configure}, the
900 following packages are also needed:
903 @item @url{https://gnupg.org/, GNU libgcrypt};
904 @item @url{https://sqlite.org, SQLite 3};
905 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
909 @cindex state directory
910 When configuring Guix on a system that already has a Guix installation,
911 be sure to specify the same state directory as the existing installation
912 using the @option{--localstatedir} option of the @command{configure}
913 script (@pxref{Directory Variables, @code{localstatedir},, standards,
914 GNU Coding Standards}). Usually, this @var{localstatedir} option is
915 set to the value @file{/var}. The @command{configure} script protects
916 against unintended misconfiguration of @var{localstatedir} so you do not
917 inadvertently corrupt your store (@pxref{The Store}).
919 @node Running the Test Suite
920 @section Running the Test Suite
923 After a successful @command{configure} and @code{make} run, it is a good
924 idea to run the test suite. It can help catch issues with the setup or
925 environment, or bugs in Guix itself---and really, reporting test
926 failures is a good way to help improve the software. To run the test
933 Test cases can run in parallel: you can use the @code{-j} option of
934 GNU@tie{}make to speed things up. The first run may take a few minutes
935 on a recent machine; subsequent runs will be faster because the store
936 that is created for test purposes will already have various things in
939 It is also possible to run a subset of the tests by defining the
940 @code{TESTS} makefile variable as in this example:
943 make check TESTS="tests/store.scm tests/cpio.scm"
946 By default, tests results are displayed at a file level. In order to
947 see the details of every individual test cases, it is possible to define
948 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
951 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
954 The underlying SRFI 64 custom Automake test driver used for the 'check'
955 test suite (located at @file{build-aux/test-driver.scm}) also allows
956 selecting which test cases to run at a finer level, via its
957 @option{--select} and @option{--exclude} options. Here's an example, to
958 run all the test cases from the @file{tests/packages.scm} test file
959 whose names start with ``transaction-upgrade-entry'':
962 export SCM_LOG_DRIVER_FLAGS="--select=^transaction-upgrade-entry"
963 make check TESTS="tests/packages.scm"
966 Those wishing to inspect the results of failed tests directly from the
967 command line can add the @option{--errors-only=yes} option to the
968 @code{SCM_LOG_DRIVER_FLAGS} makefile variable and set the @code{VERBOSE}
969 Automake makefile variable, as in:
972 make check SCM_LOG_DRIVER_FLAGS="--brief=no --errors-only=yes" VERBOSE=1
975 The @option{--show-duration=yes} option can be used to print the
976 duration of the individual test cases, when used in combination with
980 make check SCM_LOG_DRIVER_FLAGS="--brief=no --show-duration=yes"
983 @xref{Parallel Test Harness,,,automake,GNU Automake} for more
984 information about the Automake Parallel Test Harness.
986 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
987 @file{test-suite.log} file. Please specify the Guix version being used
988 as well as version numbers of the dependencies (@pxref{Requirements}) in
991 Guix also comes with a whole-system test suite that tests complete
992 Guix System instances. It can only run on systems where
993 Guix is already installed, using:
1000 or, again, by defining @code{TESTS} to select a subset of tests to run:
1003 make check-system TESTS="basic mcron"
1006 These system tests are defined in the @code{(gnu tests @dots{})}
1007 modules. They work by running the operating systems under test with
1008 lightweight instrumentation in a virtual machine (VM). They can be
1009 computationally intensive or rather cheap, depending on whether
1010 substitutes are available for their dependencies (@pxref{Substitutes}).
1011 Some of them require a lot of storage space to hold VM images.
1013 Again in case of test failures, please send @email{bug-guix@@gnu.org}
1016 @node Setting Up the Daemon
1017 @section Setting Up the Daemon
1020 Operations such as building a package or running the garbage collector
1021 are all performed by a specialized process, the @dfn{build daemon}, on
1022 behalf of clients. Only the daemon may access the store and its
1023 associated database. Thus, any operation that manipulates the store
1024 goes through the daemon. For instance, command-line tools such as
1025 @command{guix package} and @command{guix build} communicate with the
1026 daemon (@i{via} remote procedure calls) to instruct it what to do.
1028 The following sections explain how to prepare the build daemon's
1029 environment. See also @ref{Substitutes}, for information on how to allow
1030 the daemon to download pre-built binaries.
1033 * Build Environment Setup:: Preparing the isolated build environment.
1034 * Daemon Offload Setup:: Offloading builds to remote machines.
1035 * SELinux Support:: Using an SELinux policy for the daemon.
1038 @node Build Environment Setup
1039 @subsection Build Environment Setup
1041 @cindex build environment
1042 In a standard multi-user setup, Guix and its daemon---the
1043 @command{guix-daemon} program---are installed by the system
1044 administrator; @file{/gnu/store} is owned by @code{root} and
1045 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
1046 Guix tools to build packages or otherwise access the store, and the
1047 daemon will do it on their behalf, ensuring that the store is kept in a
1048 consistent state, and allowing built packages to be shared among users.
1051 When @command{guix-daemon} runs as @code{root}, you may not want package
1052 build processes themselves to run as @code{root} too, for obvious
1053 security reasons. To avoid that, a special pool of @dfn{build users}
1054 should be created for use by build processes started by the daemon.
1055 These build users need not have a shell and a home directory: they will
1056 just be used when the daemon drops @code{root} privileges in build
1057 processes. Having several such users allows the daemon to launch
1058 distinct build processes under separate UIDs, which guarantees that they
1059 do not interfere with each other---an essential feature since builds are
1060 regarded as pure functions (@pxref{Introduction}).
1062 On a GNU/Linux system, a build user pool may be created like this (using
1063 Bash syntax and the @code{shadow} commands):
1065 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
1066 @c for why `-G' is needed.
1068 # groupadd --system guixbuild
1069 # for i in $(seq -w 1 10);
1071 useradd -g guixbuild -G guixbuild \
1072 -d /var/empty -s $(which nologin) \
1073 -c "Guix build user $i" --system \
1079 The number of build users determines how many build jobs may run in
1080 parallel, as specified by the @option{--max-jobs} option
1081 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
1082 @command{guix system vm} and related commands, you may need to add the
1083 build users to the @code{kvm} group so they can access @file{/dev/kvm},
1084 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
1085 (@pxref{Invoking guix system}).
1087 The @code{guix-daemon} program may then be run as @code{root} with the
1088 following command@footnote{If your machine uses the systemd init system,
1089 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
1090 file in @file{/etc/systemd/system} will ensure that
1091 @command{guix-daemon} is automatically started. Similarly, if your
1092 machine uses the Upstart init system, drop the
1093 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
1094 file in @file{/etc/init}.}:
1097 # guix-daemon --build-users-group=guixbuild
1102 This way, the daemon starts build processes in a chroot, under one of
1103 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
1104 environment contains nothing but:
1106 @c Keep this list in sync with libstore/build.cc! -----------------------
1109 a minimal @code{/dev} directory, created mostly independently from the
1110 host @code{/dev}@footnote{``Mostly'', because while the set of files
1111 that appear in the chroot's @code{/dev} is fixed, most of these files
1112 can only be created if the host has them.};
1115 the @code{/proc} directory; it only shows the processes of the container
1116 since a separate PID name space is used;
1119 @file{/etc/passwd} with an entry for the current user and an entry for
1123 @file{/etc/group} with an entry for the user's group;
1126 @file{/etc/hosts} with an entry that maps @code{localhost} to
1130 a writable @file{/tmp} directory.
1133 You can influence the directory where the daemon stores build trees
1134 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1135 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1136 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1137 This way, the value of @env{TMPDIR} does not leak inside build
1138 environments, which avoids discrepancies in cases where build processes
1139 capture the name of their build tree.
1143 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1144 environment variables for HTTP and HTTPS downloads it performs, be it
1145 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1146 (@pxref{Substitutes}).
1148 If you are installing Guix as an unprivileged user, it is still possible
1149 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1150 However, build processes will not be isolated from one another, and not
1151 from the rest of the system. Thus, build processes may interfere with
1152 each other, and may access programs, libraries, and other files
1153 available on the system---making it much harder to view them as
1154 @emph{pure} functions.
1157 @node Daemon Offload Setup
1158 @subsection Using the Offload Facility
1162 When desired, the build daemon can @dfn{offload} derivation builds to
1163 other machines running Guix, using the @code{offload} @dfn{build
1164 hook}@footnote{This feature is available only when
1165 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1166 present.}. When that feature is enabled, a list of user-specified build
1167 machines is read from @file{/etc/guix/machines.scm}; every time a build
1168 is requested, for instance via @code{guix build}, the daemon attempts to
1169 offload it to one of the machines that satisfy the constraints of the
1170 derivation, in particular its system types---e.g., @code{x86_64-linux}.
1171 A single machine can have multiple system types, either because its
1172 architecture natively supports it, via emulation
1173 (@pxref{transparent-emulation-qemu, Transparent Emulation with QEMU}),
1174 or both. Missing prerequisites for the build are
1175 copied over SSH to the target machine, which then proceeds with the
1176 build; upon success the output(s) of the build are copied back to the
1177 initial machine. The offload facility comes with a basic scheduler that
1178 attempts to select the best machine. The best machine is chosen among
1179 the available machines based on criteria such as:
1183 The availability of a build slot. A build machine can have as many
1184 build slots (connections) as the value of the @code{parallel-builds}
1185 field of its @code{build-machine} object.
1188 Its relative speed, as defined via the @code{speed} field of its
1189 @code{build-machine} object.
1192 Its load. The normalized machine load must be lower than a threshold
1193 value, configurable via the @code{overload-threshold} field of its
1194 @code{build-machine} object.
1197 Disk space availability. More than a 100 MiB must be available.
1200 The @file{/etc/guix/machines.scm} file typically looks like this:
1203 (list (build-machine
1204 (name "eightysix.example.org")
1205 (systems (list "x86_64-linux" "i686-linux"))
1206 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1208 (speed 2.)) ;incredibly fast!
1211 (name "armeight.example.org")
1212 (systems (list "aarch64-linux"))
1213 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1216 (string-append (getenv "HOME")
1217 "/.ssh/identity-for-guix"))))
1221 In the example above we specify a list of two build machines, one for
1222 the @code{x86_64} and @code{i686} architectures and one for the
1223 @code{aarch64} architecture.
1225 In fact, this file is---not surprisingly!---a Scheme file that is
1226 evaluated when the @code{offload} hook is started. Its return value
1227 must be a list of @code{build-machine} objects. While this example
1228 shows a fixed list of build machines, one could imagine, say, using
1229 DNS-SD to return a list of potential build machines discovered in the
1230 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1231 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1234 @deftp {Data Type} build-machine
1235 This data type represents build machines to which the daemon may offload
1236 builds. The important fields are:
1241 The host name of the remote machine.
1244 The system types the remote machine supports---e.g., @code{(list
1245 "x86_64-linux" "i686-linux")}.
1248 The user account to use when connecting to the remote machine over SSH.
1249 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1250 allow non-interactive logins.
1253 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1254 This is used to authenticate the machine when we connect to it. It is a
1255 long string that looks like this:
1258 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1261 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1262 key can be found in a file such as
1263 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1265 If the machine is running the SSH daemon of GNU@tie{}lsh,
1266 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1267 similar file. It can be converted to the OpenSSH format using
1268 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1271 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1272 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1277 A number of optional fields may be specified:
1281 @item @code{port} (default: @code{22})
1282 Port number of SSH server on the machine.
1284 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1285 The SSH private key file to use when connecting to the machine, in
1286 OpenSSH format. This key must not be protected with a passphrase.
1288 Note that the default value is the private key @emph{of the root
1289 account}. Make sure it exists if you use the default.
1291 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1292 @itemx @code{compression-level} (default: @code{3})
1293 The SSH-level compression methods and compression level requested.
1295 Note that offloading relies on SSH compression to reduce bandwidth usage
1296 when transferring files to and from build machines.
1298 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1299 File name of the Unix-domain socket @command{guix-daemon} is listening
1302 @item @code{overload-threshold} (default: @code{0.6})
1303 The load threshold above which a potential offload machine is
1304 disregarded by the offload scheduler. The value roughly translates to
1305 the total processor usage of the build machine, ranging from 0.0 (0%) to
1306 1.0 (100%). It can also be disabled by setting
1307 @code{overload-threshold} to @code{#f}.
1309 @item @code{parallel-builds} (default: @code{1})
1310 The number of builds that may run in parallel on the machine.
1312 @item @code{speed} (default: @code{1.0})
1313 A ``relative speed factor''. The offload scheduler will tend to prefer
1314 machines with a higher speed factor.
1316 @item @code{features} (default: @code{'()})
1317 A list of strings denoting specific features supported by the machine.
1318 An example is @code{"kvm"} for machines that have the KVM Linux modules
1319 and corresponding hardware support. Derivations can request features by
1320 name, and they will be scheduled on matching build machines.
1325 The @command{guix} command must be in the search path on the build
1326 machines. You can check whether this is the case by running:
1329 ssh build-machine guix repl --version
1332 There is one last thing to do once @file{machines.scm} is in place. As
1333 explained above, when offloading, files are transferred back and forth
1334 between the machine stores. For this to work, you first need to
1335 generate a key pair on each machine to allow the daemon to export signed
1336 archives of files from the store (@pxref{Invoking guix archive}):
1339 # guix archive --generate-key
1343 Each build machine must authorize the key of the master machine so that
1344 it accepts store items it receives from the master:
1347 # guix archive --authorize < master-public-key.txt
1351 Likewise, the master machine must authorize the key of each build machine.
1353 All the fuss with keys is here to express pairwise mutual trust
1354 relations between the master and the build machines. Concretely, when
1355 the master receives files from a build machine (and @i{vice versa}), its
1356 build daemon can make sure they are genuine, have not been tampered
1357 with, and that they are signed by an authorized key.
1359 @cindex offload test
1360 To test whether your setup is operational, run this command on the
1367 This will attempt to connect to each of the build machines specified in
1368 @file{/etc/guix/machines.scm}, make sure Guix is
1369 available on each machine, attempt to export to the machine and import
1370 from it, and report any error in the process.
1372 If you want to test a different machine file, just specify it on the
1376 # guix offload test machines-qualif.scm
1379 Last, you can test the subset of the machines whose name matches a
1380 regular expression like this:
1383 # guix offload test machines.scm '\.gnu\.org$'
1386 @cindex offload status
1387 To display the current load of all build hosts, run this command on the
1391 # guix offload status
1395 @node SELinux Support
1396 @subsection SELinux Support
1398 @cindex SELinux, daemon policy
1399 @cindex mandatory access control, SELinux
1400 @cindex security, guix-daemon
1401 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1402 can be installed on a system where SELinux is enabled, in order to label
1403 Guix files and to specify the expected behavior of the daemon. Since
1404 Guix System does not provide an SELinux base policy, the daemon policy cannot
1405 be used on Guix System.
1407 @subsubsection Installing the SELinux policy
1408 @cindex SELinux, policy installation
1409 To install the policy run this command as root:
1412 semodule -i etc/guix-daemon.cil
1415 Then relabel the file system with @code{restorecon} or by a different
1416 mechanism provided by your system.
1418 Once the policy is installed, the file system has been relabeled, and
1419 the daemon has been restarted, it should be running in the
1420 @code{guix_daemon_t} context. You can confirm this with the following
1424 ps -Zax | grep guix-daemon
1427 Monitor the SELinux log files as you run a command like @code{guix build
1428 hello} to convince yourself that SELinux permits all necessary
1431 @subsubsection Limitations
1432 @cindex SELinux, limitations
1434 This policy is not perfect. Here is a list of limitations or quirks
1435 that should be considered when deploying the provided SELinux policy for
1440 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1441 operations involve contexts that have anything to do with
1442 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1443 but it would be preferable to define socket rules for only this label.
1446 @code{guix gc} cannot access arbitrary links to profiles. By design,
1447 the file label of the destination of a symlink is independent of the
1448 file label of the link itself. Although all profiles under
1449 $localstatedir are labelled, the links to these profiles inherit the
1450 label of the directory they are in. For links in the user’s home
1451 directory this will be @code{user_home_t}. But for links from the root
1452 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1453 directory, etc, this won’t work. @code{guix gc} would be prevented from
1454 reading and following these links.
1457 The daemon’s feature to listen for TCP connections might no longer work.
1458 This might require extra rules, because SELinux treats network sockets
1459 differently from files.
1462 Currently all files with a name matching the regular expression
1463 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1464 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1465 that name in any profile would be permitted to run in the
1466 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1467 build a package that provides this executable and convince a user to
1468 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1469 At that point SELinux could not prevent it from accessing files that are
1470 allowed for processes in that domain.
1472 You will need to relabel the store directory after all upgrades to
1473 @file{guix-daemon}, such as after running @code{guix pull}. Assuming the
1474 store is in @file{/gnu}, you can do this with @code{restorecon -vR /gnu},
1475 or by other means provided by your operating system.
1477 We could generate a much more restrictive policy at installation time,
1478 so that only the @emph{exact} file name of the currently installed
1479 @code{guix-daemon} executable would be labelled with
1480 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1481 The downside is that root would have to install or upgrade the policy at
1482 installation time whenever the Guix package that provides the
1483 effectively running @code{guix-daemon} executable is upgraded.
1486 @node Invoking guix-daemon
1487 @section Invoking @command{guix-daemon}
1489 The @command{guix-daemon} program implements all the functionality to
1490 access the store. This includes launching build processes, running the
1491 garbage collector, querying the availability of a build result, etc. It
1492 is normally run as @code{root} like this:
1495 # guix-daemon --build-users-group=guixbuild
1499 For details on how to set it up, @pxref{Setting Up the Daemon}.
1502 @cindex container, build environment
1503 @cindex build environment
1504 @cindex reproducible builds
1505 By default, @command{guix-daemon} launches build processes under
1506 different UIDs, taken from the build group specified with
1507 @option{--build-users-group}. In addition, each build process is run in a
1508 chroot environment that only contains the subset of the store that the
1509 build process depends on, as specified by its derivation
1510 (@pxref{Programming Interface, derivation}), plus a set of specific
1511 system directories. By default, the latter contains @file{/dev} and
1512 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1513 @dfn{container}: in addition to having its own file system tree, it has
1514 a separate mount name space, its own PID name space, network name space,
1515 etc. This helps achieve reproducible builds (@pxref{Features}).
1517 When the daemon performs a build on behalf of the user, it creates a
1518 build directory under @file{/tmp} or under the directory specified by
1519 its @env{TMPDIR} environment variable. This directory is shared with
1520 the container for the duration of the build, though within the container,
1521 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1523 The build directory is automatically deleted upon completion, unless the
1524 build failed and the client specified @option{--keep-failed}
1525 (@pxref{Common Build Options, @option{--keep-failed}}).
1527 The daemon listens for connections and spawns one sub-process for each session
1528 started by a client (one of the @command{guix} sub-commands). The
1529 @command{guix processes} command allows you to get an overview of the activity
1530 on your system by viewing each of the active sessions and clients.
1531 @xref{Invoking guix processes}, for more information.
1533 The following command-line options are supported:
1536 @item --build-users-group=@var{group}
1537 Take users from @var{group} to run build processes (@pxref{Setting Up
1538 the Daemon, build users}).
1540 @item --no-substitutes
1542 Do not use substitutes for build products. That is, always build things
1543 locally instead of allowing downloads of pre-built binaries
1544 (@pxref{Substitutes}).
1546 When the daemon runs with @option{--no-substitutes}, clients can still
1547 explicitly enable substitution @i{via} the @code{set-build-options}
1548 remote procedure call (@pxref{The Store}).
1550 @anchor{daemon-substitute-urls}
1551 @item --substitute-urls=@var{urls}
1552 Consider @var{urls} the default whitespace-separated list of substitute
1553 source URLs. When this option is omitted,
1554 @indicateurl{@value{SUBSTITUTE-URLS}} is used.
1556 This means that substitutes may be downloaded from @var{urls}, as long
1557 as they are signed by a trusted signature (@pxref{Substitutes}).
1559 @xref{Getting Substitutes from Other Servers}, for more information on
1560 how to configure the daemon to get substitutes from other servers.
1564 Do not use offload builds to other machines (@pxref{Daemon Offload
1565 Setup}). That is, always build things locally instead of offloading
1566 builds to remote machines.
1568 @item --cache-failures
1569 Cache build failures. By default, only successful builds are cached.
1571 When this option is used, @command{guix gc --list-failures} can be used
1572 to query the set of store items marked as failed; @command{guix gc
1573 --clear-failures} removes store items from the set of cached failures.
1574 @xref{Invoking guix gc}.
1576 @item --cores=@var{n}
1578 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1581 The default value is @code{0}, but it may be overridden by clients, such
1582 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1585 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1586 in the build process, which can then use it to exploit internal
1587 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1589 @item --max-jobs=@var{n}
1591 Allow at most @var{n} build jobs in parallel. The default value is
1592 @code{1}. Setting it to @code{0} means that no builds will be performed
1593 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1594 Setup}), or simply fail.
1596 @item --max-silent-time=@var{seconds}
1597 When the build or substitution process remains silent for more than
1598 @var{seconds}, terminate it and report a build failure.
1600 The default value is @code{0}, which disables the timeout.
1602 The value specified here can be overridden by clients (@pxref{Common
1603 Build Options, @option{--max-silent-time}}).
1605 @item --timeout=@var{seconds}
1606 Likewise, when the build or substitution process lasts for more than
1607 @var{seconds}, terminate it and report a build failure.
1609 The default value is @code{0}, which disables the timeout.
1611 The value specified here can be overridden by clients (@pxref{Common
1612 Build Options, @option{--timeout}}).
1614 @item --rounds=@var{N}
1615 Build each derivation @var{n} times in a row, and raise an error if
1616 consecutive build results are not bit-for-bit identical. Note that this
1617 setting can be overridden by clients such as @command{guix build}
1618 (@pxref{Invoking guix build}).
1620 When used in conjunction with @option{--keep-failed}, the differing
1621 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1622 This makes it easy to look for differences between the two results.
1625 Produce debugging output.
1627 This is useful to debug daemon start-up issues, but then it may be
1628 overridden by clients, for example the @option{--verbosity} option of
1629 @command{guix build} (@pxref{Invoking guix build}).
1631 @item --chroot-directory=@var{dir}
1632 Add @var{dir} to the build chroot.
1634 Doing this may change the result of build processes---for instance if
1635 they use optional dependencies found in @var{dir} when it is available,
1636 and not otherwise. For that reason, it is not recommended to do so.
1637 Instead, make sure that each derivation declares all the inputs that it
1640 @item --disable-chroot
1641 Disable chroot builds.
1643 Using this option is not recommended since, again, it would allow build
1644 processes to gain access to undeclared dependencies. It is necessary,
1645 though, when @command{guix-daemon} is running under an unprivileged user
1648 @item --log-compression=@var{type}
1649 Compress build logs according to @var{type}, one of @code{gzip},
1650 @code{bzip2}, or @code{none}.
1652 Unless @option{--lose-logs} is used, all the build logs are kept in the
1653 @var{localstatedir}. To save space, the daemon automatically compresses
1654 them with Bzip2 by default.
1656 @item --discover[=yes|no]
1657 Whether to discover substitute servers on the local network using mDNS
1660 This feature is still experimental. However, here are a few
1665 It might be faster/less expensive than fetching from remote servers;
1667 There are no security risks, only genuine substitutes will be used
1668 (@pxref{Substitute Authentication});
1670 An attacker advertising @command{guix publish} on your LAN cannot serve
1671 you malicious binaries, but they can learn what software you’re
1674 Servers may serve substitute over HTTP, unencrypted, so anyone on the
1675 LAN can see what software you’re installing.
1678 It is also possible to enable or disable substitute server discovery at
1679 run-time by running:
1682 herd discover guix-daemon on
1683 herd discover guix-daemon off
1686 @item --disable-deduplication
1687 @cindex deduplication
1688 Disable automatic file ``deduplication'' in the store.
1690 By default, files added to the store are automatically ``deduplicated'':
1691 if a newly added file is identical to another one found in the store,
1692 the daemon makes the new file a hard link to the other file. This can
1693 noticeably reduce disk usage, at the expense of slightly increased
1694 input/output load at the end of a build process. This option disables
1697 @item --gc-keep-outputs[=yes|no]
1698 Tell whether the garbage collector (GC) must keep outputs of live
1702 @cindex garbage collector roots
1703 When set to @code{yes}, the GC will keep the outputs of any live
1704 derivation available in the store---the @file{.drv} files. The default
1705 is @code{no}, meaning that derivation outputs are kept only if they are
1706 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1709 @item --gc-keep-derivations[=yes|no]
1710 Tell whether the garbage collector (GC) must keep derivations
1711 corresponding to live outputs.
1713 When set to @code{yes}, as is the case by default, the GC keeps
1714 derivations---i.e., @file{.drv} files---as long as at least one of their
1715 outputs is live. This allows users to keep track of the origins of
1716 items in their store. Setting it to @code{no} saves a bit of disk
1719 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1720 liveness to flow from outputs to derivations, and setting
1721 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1722 derivations to outputs. When both are set to @code{yes}, the effect is
1723 to keep all the build prerequisites (the sources, compiler, libraries,
1724 and other build-time tools) of live objects in the store, regardless of
1725 whether these prerequisites are reachable from a GC root. This is
1726 convenient for developers since it saves rebuilds or downloads.
1728 @item --impersonate-linux-2.6
1729 On Linux-based systems, impersonate Linux 2.6. This means that the
1730 kernel's @command{uname} system call will report 2.6 as the release number.
1732 This might be helpful to build programs that (usually wrongfully) depend
1733 on the kernel version number.
1736 Do not keep build logs. By default they are kept under
1737 @file{@var{localstatedir}/guix/log}.
1739 @item --system=@var{system}
1740 Assume @var{system} as the current system type. By default it is the
1741 architecture/kernel pair found at configure time, such as
1742 @code{x86_64-linux}.
1744 @item --listen=@var{endpoint}
1745 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1746 as the file name of a Unix-domain socket if it starts with
1747 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1748 host name or host name and port to listen to. Here are a few examples:
1751 @item --listen=/gnu/var/daemon
1752 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1753 creating it if needed.
1755 @item --listen=localhost
1756 @cindex daemon, remote access
1757 @cindex remote access to the daemon
1758 @cindex daemon, cluster setup
1759 @cindex clusters, daemon setup
1760 Listen for TCP connections on the network interface corresponding to
1761 @code{localhost}, on port 44146.
1763 @item --listen=128.0.0.42:1234
1764 Listen for TCP connections on the network interface corresponding to
1765 @code{128.0.0.42}, on port 1234.
1768 This option can be repeated multiple times, in which case
1769 @command{guix-daemon} accepts connections on all the specified
1770 endpoints. Users can tell client commands what endpoint to connect to
1771 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1772 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1775 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1776 @option{--listen=@var{host}} is suitable on local networks, such as
1777 clusters, where only trusted nodes may connect to the build daemon. In
1778 other cases where remote access to the daemon is needed, we recommend
1779 using Unix-domain sockets along with SSH.
1782 When @option{--listen} is omitted, @command{guix-daemon} listens for
1783 connections on the Unix-domain socket located at
1784 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1788 @node Application Setup
1789 @section Application Setup
1791 @cindex foreign distro
1792 When using Guix on top of GNU/Linux distribution other than Guix System---a
1793 so-called @dfn{foreign distro}---a few additional steps are needed to
1794 get everything in place. Here are some of them.
1798 @anchor{locales-and-locpath}
1799 @cindex locales, when not on Guix System
1801 @vindex GUIX_LOCPATH
1802 Packages installed @i{via} Guix will not use the locale data of the
1803 host system. Instead, you must first install one of the locale packages
1804 available with Guix and then define the @env{GUIX_LOCPATH} environment
1808 $ guix install glibc-locales
1809 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1812 Note that the @code{glibc-locales} package contains data for all the
1813 locales supported by the GNU@tie{}libc and weighs in at around
1814 917@tie{}MiB@. Alternatively, the @code{glibc-utf8-locales} is smaller but
1815 limited to a few UTF-8 locales.
1817 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1818 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1819 Manual}). There are two important differences though:
1823 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1824 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1825 to make sure the programs of the foreign distro will not end up loading
1826 incompatible locale data.
1829 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1830 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1831 should your Guix profile contain a mixture of programs linked against
1832 different libc version, each libc version will only try to load locale
1833 data in the right format.
1836 This is important because the locale data format used by different libc
1837 versions may be incompatible.
1839 @subsection Name Service Switch
1841 @cindex name service switch, glibc
1842 @cindex NSS (name service switch), glibc
1843 @cindex nscd (name service caching daemon)
1844 @cindex name service caching daemon (nscd)
1845 When using Guix on a foreign distro, we @emph{strongly recommend} that
1846 the system run the GNU C library's @dfn{name service cache daemon},
1847 @command{nscd}, which should be listening on the
1848 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1849 installed with Guix may fail to look up host names or user accounts, or
1850 may even crash. The next paragraphs explain why.
1852 @cindex @file{nsswitch.conf}
1853 The GNU C library implements a @dfn{name service switch} (NSS), which is
1854 an extensible mechanism for ``name lookups'' in general: host name
1855 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1856 The GNU C Library Reference Manual}).
1858 @cindex Network information service (NIS)
1859 @cindex NIS (Network information service)
1860 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1861 lookup implementations: for example, the @code{nss-mdns} plugin allow
1862 resolution of @code{.local} host names, the @code{nis} plugin allows
1863 user account lookup using the Network information service (NIS), and so
1864 on. These extra ``lookup services'' are configured system-wide in
1865 @file{/etc/nsswitch.conf}, and all the programs running on the system
1866 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1869 When they perform a name lookup---for instance by calling the
1870 @code{getaddrinfo} function in C---applications first try to connect to
1871 the nscd; on success, nscd performs name lookups on their behalf. If
1872 the nscd is not running, then they perform the name lookup by
1873 themselves, by loading the name lookup services into their own address
1874 space and running it. These name lookup services---the
1875 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1876 the host system's C library, rather than from the C library the
1877 application is linked against (the C library coming from Guix).
1879 And this is where the problem is: if your application is linked against
1880 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1881 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1882 likely crash or have its name lookups fail unexpectedly.
1884 Running @command{nscd} on the system, among other advantages, eliminates
1885 this binary incompatibility problem because those @code{libnss_*.so}
1886 files are loaded in the @command{nscd} process, not in applications
1889 @subsection X11 Fonts
1892 The majority of graphical applications use Fontconfig to locate and
1893 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1894 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1895 by default. Thus, to allow graphical applications installed with Guix
1896 to display fonts, you have to install fonts with Guix as well.
1897 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1898 @code{font-gnu-freefont}.
1900 @cindex @code{fc-cache}
1902 Once you have installed or removed fonts, or when you notice an
1903 application that does not find fonts, you may need to install Fontconfig
1904 and to force an update of its font cache by running:
1907 guix install fontconfig
1911 To display text written in Chinese languages, Japanese, or Korean in
1912 graphical applications, consider installing
1913 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1914 has multiple outputs, one per language family (@pxref{Packages with
1915 Multiple Outputs}). For instance, the following command installs fonts
1916 for Chinese languages:
1919 guix install font-adobe-source-han-sans:cn
1922 @cindex @code{xterm}
1923 Older programs such as @command{xterm} do not use Fontconfig and instead
1924 rely on server-side font rendering. Such programs require to specify a
1925 full name of a font using XLFD (X Logical Font Description), like this:
1928 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1931 To be able to use such full names for the TrueType fonts installed in
1932 your Guix profile, you need to extend the font path of the X server:
1934 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1935 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1937 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1940 @cindex @code{xlsfonts}
1941 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1942 to make sure your TrueType fonts are listed there.
1945 @subsection X.509 Certificates
1947 @cindex @code{nss-certs}
1948 The @code{nss-certs} package provides X.509 certificates, which allow
1949 programs to authenticate Web servers accessed over HTTPS.
1951 When using Guix on a foreign distro, you can install this package and
1952 define the relevant environment variables so that packages know where to
1953 look for certificates. @xref{X.509 Certificates}, for detailed
1956 @subsection Emacs Packages
1958 @cindex @code{emacs}
1959 When you install Emacs packages with Guix, the Elisp files are placed
1960 under the @file{share/emacs/site-lisp/} directory of the profile in
1961 which they are installed. The Elisp libraries are made available to
1962 Emacs through the @env{EMACSLOADPATH} environment variable, which is
1963 set when installing Emacs itself.
1965 Additionally, autoload definitions are automatically evaluated at the
1966 initialization of Emacs, by the Guix-specific
1967 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
1968 want to avoid auto-loading the Emacs packages installed with Guix, you
1969 can do so by running Emacs with the @option{--no-site-file} option
1970 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1973 @node Upgrading Guix
1974 @section Upgrading Guix
1976 @cindex Upgrading Guix, on a foreign distro
1978 To upgrade Guix, run:
1984 @xref{Invoking guix pull}, for more information.
1986 @cindex upgrading Guix for the root user, on a foreign distro
1987 @cindex upgrading the Guix daemon, on a foreign distro
1988 @cindex @command{guix pull} for the root user, on a foreign distro
1990 On a foreign distro, you can upgrade the build daemon by running:
1997 followed by (assuming your distro uses the systemd service management
2001 systemctl restart guix-daemon.service
2004 On Guix System, upgrading the daemon is achieved by reconfiguring the
2005 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
2009 @c *********************************************************************
2010 @node System Installation
2011 @chapter System Installation
2013 @cindex installing Guix System
2014 @cindex Guix System, installation
2015 This section explains how to install Guix System
2016 on a machine. Guix, as a package manager, can
2017 also be installed on top of a running GNU/Linux system,
2018 @pxref{Installation}.
2022 @c This paragraph is for people reading this from tty2 of the
2023 @c installation image.
2024 You are reading this documentation with an Info reader. For details on
2025 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
2026 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
2027 Info}. Hit @kbd{l} afterwards to come back here.
2029 Alternatively, run @command{info info} in another tty to keep the manual
2035 * Limitations:: What you can expect.
2036 * Hardware Considerations:: Supported hardware.
2037 * USB Stick and DVD Installation:: Preparing the installation medium.
2038 * Preparing for Installation:: Networking, partitioning, etc.
2039 * Guided Graphical Installation:: Easy graphical installation.
2040 * Manual Installation:: Manual installation for wizards.
2041 * After System Installation:: When installation succeeded.
2042 * Installing Guix in a VM:: Guix System playground.
2043 * Building the Installation Image:: How this comes to be.
2047 @section Limitations
2049 We consider Guix System to be ready for a wide range of ``desktop'' and server
2050 use cases. The reliability guarantees it provides---transactional upgrades
2051 and rollbacks, reproducibility---make it a solid foundation.
2053 Nevertheless, before you proceed with the installation, be aware of the
2054 following noteworthy limitations applicable to version @value{VERSION}:
2058 More and more system services are provided (@pxref{Services}), but some
2062 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
2063 as well as a number of X11 window managers. However, KDE is currently
2067 More than a disclaimer, this is an invitation to report issues (and success
2068 stories!), and to join us in improving it. @xref{Contributing}, for more
2072 @node Hardware Considerations
2073 @section Hardware Considerations
2075 @cindex hardware support on Guix System
2076 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
2077 builds around the kernel Linux-libre, which means that only hardware for
2078 which free software drivers and firmware exist is supported. Nowadays,
2079 a wide range of off-the-shelf hardware is supported on
2080 GNU/Linux-libre---from keyboards to graphics cards to scanners and
2081 Ethernet controllers. Unfortunately, there are still areas where
2082 hardware vendors deny users control over their own computing, and such
2083 hardware is not supported on Guix System.
2085 @cindex WiFi, hardware support
2086 One of the main areas where free drivers or firmware are lacking is WiFi
2087 devices. WiFi devices known to work include those using Atheros chips
2088 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
2089 driver, and those using Broadcom/AirForce chips (BCM43xx with
2090 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
2091 Linux-libre driver. Free firmware exists for both and is available
2092 out-of-the-box on Guix System, as part of @code{%base-firmware}
2093 (@pxref{operating-system Reference, @code{firmware}}).
2095 @cindex RYF, Respects Your Freedom
2096 The @uref{https://www.fsf.org/, Free Software Foundation} runs
2097 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
2098 certification program for hardware products that respect your freedom
2099 and your privacy and ensure that you have control over your device. We
2100 encourage you to check the list of RYF-certified devices.
2102 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
2103 web site. It contains a catalog of hardware devices with information
2104 about their support in GNU/Linux.
2107 @node USB Stick and DVD Installation
2108 @section USB Stick and DVD Installation
2110 An ISO-9660 installation image that can be written to a USB stick or
2111 burnt to a DVD can be downloaded from
2112 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso},
2113 where you can replace @code{x86_64-linux} with one of:
2117 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
2120 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
2123 @c start duplication of authentication part from ``Binary Installation''
2124 Make sure to download the associated @file{.sig} file and to verify the
2125 authenticity of the image against it, along these lines:
2128 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
2129 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
2132 If that command fails because you do not have the required public key,
2133 then run this command to import it:
2136 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
2137 -qO - | gpg --import -
2141 and rerun the @code{gpg --verify} command.
2143 Take note that a warning like ``This key is not certified with a trusted
2144 signature!'' is normal.
2148 This image contains the tools necessary for an installation.
2149 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
2151 @unnumberedsubsec Copying to a USB Stick
2153 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
2154 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
2155 copy the image with:
2158 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX status=progress
2162 Access to @file{/dev/sdX} usually requires root privileges.
2164 @unnumberedsubsec Burning on a DVD
2166 Insert a blank DVD into your machine, and determine
2167 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
2168 copy the image with:
2171 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
2174 Access to @file{/dev/srX} usually requires root privileges.
2176 @unnumberedsubsec Booting
2178 Once this is done, you should be able to reboot the system and boot from
2179 the USB stick or DVD@. The latter usually requires you to get in the
2180 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2181 In order to boot from Libreboot, switch to the command mode by pressing
2182 the @kbd{c} key and type @command{search_grub usb}.
2184 @xref{Installing Guix in a VM}, if, instead, you would like to install
2185 Guix System in a virtual machine (VM).
2188 @node Preparing for Installation
2189 @section Preparing for Installation
2191 Once you have booted, you can use the guided graphical installer, which makes
2192 it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
2193 if you are already familiar with GNU/Linux and if you want more control than
2194 what the graphical installer provides, you can choose the ``manual''
2195 installation process (@pxref{Manual Installation}).
2197 The graphical installer is available on TTY1. You can obtain root shells on
2198 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2199 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2200 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2201 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2202 which allows you to select text with the left mouse button and to paste it
2203 with the middle button.
2206 Installation requires access to the Internet so that any missing
2207 dependencies of your system configuration can be downloaded. See the
2208 ``Networking'' section below.
2211 @node Guided Graphical Installation
2212 @section Guided Graphical Installation
2214 The graphical installer is a text-based user interface. It will guide you,
2215 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2217 The first dialog boxes allow you to set up the system as you use it during the
2218 installation: you can choose the language, keyboard layout, and set up
2219 networking, which will be used during the installation. The image below shows
2220 the networking dialog.
2222 @image{images/installer-network,5in,, networking setup with the graphical installer}
2224 Later steps allow you to partition your hard disk, as shown in the image
2225 below, to choose whether or not to use encrypted file systems, to enter the
2226 host name and root password, and to create an additional account, among other
2229 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2231 Note that, at any time, the installer allows you to exit the current
2232 installation step and resume at a previous step, as show in the image below.
2234 @image{images/installer-resume,5in,, resuming the installation process}
2236 Once you're done, the installer produces an operating system configuration and
2237 displays it (@pxref{Using the Configuration System}). At that point you can
2238 hit ``OK'' and installation will proceed. On success, you can reboot into the
2239 new system and enjoy. @xref{After System Installation}, for what's next!
2242 @node Manual Installation
2243 @section Manual Installation
2245 This section describes how you would ``manually'' install GNU@tie{}Guix System
2246 on your machine. This option requires familiarity with GNU/Linux, with the
2247 shell, and with common administration tools. If you think this is not for
2248 you, consider using the guided graphical installer (@pxref{Guided Graphical
2251 The installation system provides root shells on TTYs 3 to 6; press
2252 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2253 many common tools needed to install the system. But it is also a full-blown
2254 Guix System, which means that you can install additional packages, should you
2255 need it, using @command{guix package} (@pxref{Invoking guix package}).
2258 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2259 * Proceeding with the Installation:: Installing.
2262 @node Keyboard Layout and Networking and Partitioning
2263 @subsection Keyboard Layout, Networking, and Partitioning
2265 Before you can install the system, you may want to adjust the keyboard layout,
2266 set up networking, and partition your target hard disk. This section will
2267 guide you through this.
2269 @subsubsection Keyboard Layout
2271 @cindex keyboard layout
2272 The installation image uses the US qwerty keyboard layout. If you want
2273 to change it, you can use the @command{loadkeys} command. For example,
2274 the following command selects the Dvorak keyboard layout:
2280 See the files under @file{/run/current-system/profile/share/keymaps} for
2281 a list of available keyboard layouts. Run @command{man loadkeys} for
2284 @subsubsection Networking
2286 Run the following command to see what your network interfaces are called:
2293 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2299 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2300 Wired interfaces have a name starting with @samp{e}; for example, the
2301 interface corresponding to the first on-board Ethernet controller is
2302 called @samp{eno1}. Wireless interfaces have a name starting with
2303 @samp{w}, like @samp{w1p2s0}.
2306 @item Wired connection
2307 To configure a wired network run the following command, substituting
2308 @var{interface} with the name of the wired interface you want to use.
2311 ifconfig @var{interface} up
2315 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2318 ip link set @var{interface} up
2321 @item Wireless connection
2324 To configure wireless networking, you can create a configuration file
2325 for the @command{wpa_supplicant} configuration tool (its location is not
2326 important) using one of the available text editors such as
2330 nano wpa_supplicant.conf
2333 As an example, the following stanza can go to this file and will work
2334 for many wireless networks, provided you give the actual SSID and
2335 passphrase for the network you are connecting to:
2339 ssid="@var{my-ssid}"
2341 psk="the network's secret passphrase"
2345 Start the wireless service and run it in the background with the
2346 following command (substitute @var{interface} with the name of the
2347 network interface you want to use):
2350 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2353 Run @command{man wpa_supplicant} for more information.
2357 At this point, you need to acquire an IP address. On a network where IP
2358 addresses are automatically assigned @i{via} DHCP, you can run:
2361 dhclient -v @var{interface}
2364 Try to ping a server to see if networking is up and running:
2370 Setting up network access is almost always a requirement because the
2371 image does not contain all the software and tools that may be needed.
2373 @cindex proxy, during system installation
2374 If you need HTTP and HTTPS access to go through a proxy, run the
2378 herd set-http-proxy guix-daemon @var{URL}
2382 where @var{URL} is the proxy URL, for example
2383 @code{http://example.org:8118}.
2385 @cindex installing over SSH
2386 If you want to, you can continue the installation remotely by starting
2390 herd start ssh-daemon
2393 Make sure to either set a password with @command{passwd}, or configure
2394 OpenSSH public key authentication before logging in.
2396 @subsubsection Disk Partitioning
2398 Unless this has already been done, the next step is to partition, and
2399 then format the target partition(s).
2401 The installation image includes several partitioning tools, including
2402 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2403 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2404 the partition layout you want:
2410 If your disk uses the GUID Partition Table (GPT) format and you plan to
2411 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2412 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2415 @cindex EFI, installation
2416 @cindex UEFI, installation
2417 @cindex ESP, EFI system partition
2418 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2419 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2420 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2423 parted /dev/sda set 1 esp on
2427 @vindex grub-bootloader
2428 @vindex grub-efi-bootloader
2429 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2430 @file{/sys/firmware/efi} exists in the installation image, then you should
2431 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2432 Otherwise you should use the BIOS-based GRUB, known as
2433 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2437 Once you are done partitioning the target hard disk drive, you have to
2438 create a file system on the relevant partition(s)@footnote{Currently
2439 Guix System only supports ext4, btrfs, JFS, and F2FS file systems. In
2440 particular, code that reads file system UUIDs and labels only works for these
2441 file system types.}. For the ESP, if you have one and assuming it is
2442 @file{/dev/sda1}, run:
2445 mkfs.fat -F32 /dev/sda1
2448 For the root file system, ext4 is the most widely used format. Other
2449 file systems, such as Btrfs, support compression, which is reported to
2450 nicely complement file deduplication that the daemon performs
2451 independently of the file system (@pxref{Invoking guix-daemon,
2454 Preferably, assign file systems a label so that you can easily and
2455 reliably refer to them in @code{file-system} declarations (@pxref{File
2456 Systems}). This is typically done using the @code{-L} option of
2457 @command{mkfs.ext4} and related commands. So, assuming the target root
2458 partition lives at @file{/dev/sda2}, a file system with the label
2459 @code{my-root} can be created with:
2462 mkfs.ext4 -L my-root /dev/sda2
2465 @cindex encrypted disk
2466 If you are instead planning to encrypt the root partition, you can use
2467 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2468 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2469 @code{man cryptsetup}} for more information). Assuming you want to
2470 store the root partition on @file{/dev/sda2}, the command sequence would
2471 be along these lines:
2474 cryptsetup luksFormat /dev/sda2
2475 cryptsetup open --type luks /dev/sda2 my-partition
2476 mkfs.ext4 -L my-root /dev/mapper/my-partition
2479 Once that is done, mount the target file system under @file{/mnt}
2480 with a command like (again, assuming @code{my-root} is the label of the
2484 mount LABEL=my-root /mnt
2487 Also mount any other file systems you would like to use on the target
2488 system relative to this path. If you have opted for @file{/boot/efi} as an
2489 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2490 found by @code{guix system init} afterwards.
2492 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2493 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2494 sure to initialize them with @command{mkswap}. Assuming you have one
2495 swap partition on @file{/dev/sda3}, you would run:
2502 Alternatively, you may use a swap file. For example, assuming that in
2503 the new system you want to use the file @file{/swapfile} as a swap file,
2504 you would run@footnote{This example will work for many types of file
2505 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2506 btrfs), the required steps may be different. For details, see the
2507 manual pages for @command{mkswap} and @command{swapon}.}:
2510 # This is 10 GiB of swap space. Adjust "count" to change the size.
2511 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2512 # For security, make the file readable and writable only by root.
2513 chmod 600 /mnt/swapfile
2514 mkswap /mnt/swapfile
2515 swapon /mnt/swapfile
2518 Note that if you have encrypted the root partition and created a swap
2519 file in its file system as described above, then the encryption also
2520 protects the swap file, just like any other file in that file system.
2522 @node Proceeding with the Installation
2523 @subsection Proceeding with the Installation
2525 With the target partitions ready and the target root mounted on
2526 @file{/mnt}, we're ready to go. First, run:
2529 herd start cow-store /mnt
2532 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2533 during the installation phase are written to the target disk on @file{/mnt}
2534 rather than kept in memory. This is necessary because the first phase of
2535 the @command{guix system init} command (see below) entails downloads or
2536 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2538 Next, you have to edit a file and
2539 provide the declaration of the operating system to be installed. To
2540 that end, the installation system comes with three text editors. We
2541 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2542 supports syntax highlighting and parentheses matching; other editors
2543 include GNU Zile (an Emacs clone), and
2544 nvi (a clone of the original BSD @command{vi} editor).
2545 We strongly recommend storing that file on the target root file system, say,
2546 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2547 configuration file once you have rebooted into the newly-installed system.
2549 @xref{Using the Configuration System}, for an overview of the
2550 configuration file. The example configurations discussed in that
2551 section are available under @file{/etc/configuration} in the
2552 installation image. Thus, to get started with a system configuration
2553 providing a graphical display server (a ``desktop'' system), you can run
2554 something along these lines:
2558 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2559 # nano /mnt/etc/config.scm
2562 You should pay attention to what your configuration file contains, and
2567 Make sure the @code{bootloader-configuration} form refers to the target
2568 you want to install GRUB on. It should mention @code{grub-bootloader} if
2569 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2570 for newer UEFI systems. For legacy systems, the @code{target} field
2571 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2572 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2573 currently mounted and a @code{file-system} entry is specified in your
2577 Be sure that your file system labels match the value of their respective
2578 @code{device} fields in your @code{file-system} configuration, assuming
2579 your @code{file-system} configuration uses the @code{file-system-label}
2580 procedure in its @code{device} field.
2583 If there are encrypted or RAID partitions, make sure to add a
2584 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2587 Once you are done preparing the configuration file, the new system must
2588 be initialized (remember that the target root file system is mounted
2592 guix system init /mnt/etc/config.scm /mnt
2596 This copies all the necessary files and installs GRUB on
2597 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2598 more information, @pxref{Invoking guix system}. This command may trigger
2599 downloads or builds of missing packages, which can take some time.
2601 Once that command has completed---and hopefully succeeded!---you can run
2602 @command{reboot} and boot into the new system. The @code{root} password
2603 in the new system is initially empty; other users' passwords need to be
2604 initialized by running the @command{passwd} command as @code{root},
2605 unless your configuration specifies otherwise
2606 (@pxref{user-account-password, user account passwords}).
2607 @xref{After System Installation}, for what's next!
2610 @node After System Installation
2611 @section After System Installation
2613 Success, you've now booted into Guix System! From then on, you can update the
2614 system whenever you want by running, say:
2618 sudo guix system reconfigure /etc/config.scm
2622 This builds a new system generation with the latest packages and services
2623 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2624 your system includes the latest security updates (@pxref{Security Updates}).
2626 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2628 @cindex sudo vs. @command{guix pull}
2629 Note that @command{sudo guix} runs your user's @command{guix} command and
2630 @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
2631 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2633 The difference matters here, because @command{guix pull} updates
2634 the @command{guix} command and package definitions only for the user it is run
2635 as. This means that if you choose to use @command{guix system reconfigure} in
2636 root's login shell, you'll need to @command{guix pull} separately.
2639 Now, @pxref{Getting Started}, and
2640 join us on @code{#guix} on the Libera Chat IRC network or on
2641 @email{guix-devel@@gnu.org} to share your experience!
2644 @node Installing Guix in a VM
2645 @section Installing Guix in a Virtual Machine
2647 @cindex virtual machine, Guix System installation
2648 @cindex virtual private server (VPS)
2649 @cindex VPS (virtual private server)
2650 If you'd like to install Guix System in a virtual machine (VM) or on a
2651 virtual private server (VPS) rather than on your beloved machine, this
2654 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2655 disk image, follow these steps:
2659 First, retrieve and decompress the Guix system installation image as
2660 described previously (@pxref{USB Stick and DVD Installation}).
2663 Create a disk image that will hold the installed system. To make a
2664 qcow2-formatted disk image, use the @command{qemu-img} command:
2667 qemu-img create -f qcow2 guix-system.img 50G
2670 The resulting file will be much smaller than 50 GB (typically less than
2671 1 MB), but it will grow as the virtualized storage device is filled up.
2674 Boot the USB installation image in an VM:
2677 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2678 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2679 -drive file=guix-system.img \
2680 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2683 @code{-enable-kvm} is optional, but significantly improves performance,
2684 @pxref{Running Guix in a VM}.
2687 You're now root in the VM, proceed with the installation process.
2688 @xref{Preparing for Installation}, and follow the instructions.
2691 Once installation is complete, you can boot the system that's on your
2692 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2695 @node Building the Installation Image
2696 @section Building the Installation Image
2698 @cindex installation image
2699 The installation image described above was built using the @command{guix
2700 system} command, specifically:
2703 guix system image -t iso9660 gnu/system/install.scm
2706 Have a look at @file{gnu/system/install.scm} in the source tree,
2707 and see also @ref{Invoking guix system} for more information
2708 about the installation image.
2710 @section Building the Installation Image for ARM Boards
2712 Many ARM boards require a specific variant of the
2713 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2715 If you build a disk image and the bootloader is not available otherwise
2716 (on another boot drive etc), it's advisable to build an image that
2717 includes the bootloader, specifically:
2720 guix system image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2723 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2724 board, a list of possible boards will be printed.
2726 @c *********************************************************************
2727 @node Getting Started
2728 @chapter Getting Started
2730 Presumably, you've reached this section because either you have
2731 installed Guix on top of another distribution (@pxref{Installation}), or
2732 you've installed the standalone Guix System (@pxref{System
2733 Installation}). It's time for you to get started using Guix and this
2734 section aims to help you do that and give you a feel of what it's like.
2736 Guix is about installing software, so probably the first thing you'll
2737 want to do is to actually look for software. Let's say you're looking
2738 for a text editor, you can run:
2741 guix search text editor
2744 This command shows you a number of matching @dfn{packages}, each time
2745 showing the package's name, version, a description, and additional info.
2746 Once you've found out the one you want to use, let's say Emacs (ah ha!),
2747 you can go ahead and install it (run this command as a regular user,
2748 @emph{no need for root privileges}!):
2755 You've installed your first package, congrats! The package is now
2756 visible in your default @dfn{profile}, @file{$HOME/.guix-profile}---a
2757 profile is a directory containing installed packages.
2758 In the process, you've
2759 probably noticed that Guix downloaded pre-built binaries; or, if you
2760 explicitly chose to @emph{not} use pre-built binaries, then probably
2761 Guix is still building software (@pxref{Substitutes}, for more info).
2763 Unless you're using Guix System, the @command{guix install} command must
2764 have printed this hint:
2767 hint: Consider setting the necessary environment variables by running:
2769 GUIX_PROFILE="$HOME/.guix-profile"
2770 . "$GUIX_PROFILE/etc/profile"
2772 Alternately, see `guix package --search-paths -p "$HOME/.guix-profile"'.
2775 Indeed, you must now tell your shell where @command{emacs} and other
2776 programs installed with Guix are to be found. Pasting the two lines
2777 above will do just that: it will add
2778 @code{$HOME/.guix-profile/bin}---which is where the installed package
2779 is---to the @code{PATH} environment variable. You can paste these two
2780 lines in your shell so they take effect right away, but more importantly
2781 you should add them to @file{~/.bash_profile} (or equivalent file if you
2782 do not use Bash) so that environment variables are set next time you
2783 spawn a shell. You only need to do this once and other search paths
2784 environment variables will be taken care of similarly---e.g., if you
2785 eventually install @code{python} and Python libraries, @code{PYTHONPATH}
2788 You can go on installing packages at your will. To list installed
2792 guix package --list-installed
2795 To remove a package, you would unsurprisingly run @command{guix remove}.
2796 A distinguishing feature is the ability to @dfn{roll back} any operation
2797 you made---installation, removal, upgrade---by simply typing:
2800 guix package --roll-back
2803 This is because each operation is in fact a @dfn{transaction} that
2804 creates a new @dfn{generation}. These generations and the difference
2805 between them can be displayed by running:
2808 guix package --list-generations
2811 Now you know the basics of package management!
2813 @quotation Going further
2814 @xref{Package Management}, for more about package management. You may
2815 like @dfn{declarative} package management with @command{guix package
2816 --manifest}, managing separate @dfn{profiles} with @option{--profile},
2817 deleting old generations, collecting garbage, and other nifty features
2818 that will come in handy as you become more familiar with Guix. If you
2819 are a developer, @pxref{Development} for additional tools. And if
2820 you're curious, @pxref{Features}, to peek under the hood.
2823 Once you've installed a set of packages, you will want to periodically
2824 @emph{upgrade} them to the latest and greatest version. To do that, you
2825 will first pull the latest revision of Guix and its package collection:
2831 The end result is a new @command{guix} command, under
2832 @file{~/.config/guix/current/bin}. Unless you're on Guix System, the
2833 first time you run @command{guix pull}, be sure to follow the hint that
2834 the command prints and, similar to what we saw above, paste these two
2835 lines in your terminal and @file{.bash_profile}:
2838 GUIX_PROFILE="$HOME/.config/guix/current"
2839 . "$GUIX_PROFILE/etc/profile"
2843 You must also instruct your shell to point to this new @command{guix}:
2849 At this point, you're running a brand new Guix. You can thus go ahead
2850 and actually upgrade all the packages you previously installed:
2856 As you run this command, you will see that binaries are downloaded (or
2857 perhaps some packages are built), and eventually you end up with the
2858 upgraded packages. Should one of these upgraded packages not be to your
2859 liking, remember you can always roll back!
2861 You can display the exact revision of Guix you're currently using by
2868 The information it displays is @emph{all it takes to reproduce the exact
2869 same Guix}, be it at a different point in time or on a different
2872 @quotation Going further
2873 @xref{Invoking guix pull}, for more information. @xref{Channels}, on
2874 how to specify additional @dfn{channels} to pull packages from, how to
2875 replicate Guix, and more. You may also find @command{time-machine}
2876 handy (@pxref{Invoking guix time-machine}).
2879 If you installed Guix System, one of the first things you'll want to do
2880 is to upgrade your system. Once you've run @command{guix pull} to get
2881 the latest Guix, you can upgrade the system like this:
2884 sudo guix system reconfigure /etc/config.scm
2887 Upon completion, the system runs the latest versions of its software
2888 packages. When you eventually reboot, you'll notice a sub-menu in the
2889 bootloader that reads ``Old system generations'': it's what allows you
2890 to boot @emph{an older generation of your system}, should the latest
2891 generation be ``broken'' or otherwise unsatisfying. Just like for
2892 packages, you can always @emph{roll back} to a previous generation
2893 @emph{of the whole system}:
2896 sudo guix system roll-back
2899 There are many things you'll probably want to tweak on your system:
2900 adding new user accounts, adding new system services, fiddling with the
2901 configuration of those services, etc. The system configuration is
2902 @emph{entirely} described in the @file{/etc/config.scm} file.
2903 @xref{Using the Configuration System}, to learn how to change it.
2905 Now you know enough to get started!
2907 @quotation Resources
2908 The rest of this manual provides a reference for all things Guix. Here
2909 are some additional resources you may find useful:
2913 @xref{Top,,, guix-cookbook, The GNU Guix Cookbook}, for a list of
2914 ``how-to'' style of recipes for a variety of applications.
2917 The @uref{https://guix.gnu.org/guix-refcard.pdf, GNU Guix Reference
2918 Card} lists in two pages most of the commands and options you'll ever
2922 The web site contains @uref{https://guix.gnu.org/en/videos/,
2923 instructional videos} covering topics such as everyday use of Guix, how
2924 to get help, and how to become a contributor.
2927 @xref{Documentation}, to learn how to access documentation on your
2931 We hope you will enjoy Guix as much as the community enjoys building it!
2934 @c *********************************************************************
2935 @node Package Management
2936 @chapter Package Management
2939 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2940 remove software packages, without having to know about their build
2941 procedures or dependencies. Guix also goes beyond this obvious set of
2944 This chapter describes the main features of Guix, as well as the
2945 package management tools it provides. Along with the command-line
2946 interface described below (@pxref{Invoking guix package, @code{guix
2947 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2948 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2949 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2953 guix install emacs-guix
2957 * Features:: How Guix will make your life brighter.
2958 * Invoking guix package:: Package installation, removal, etc.
2959 * Substitutes:: Downloading pre-built binaries.
2960 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2961 * Invoking guix gc:: Running the garbage collector.
2962 * Invoking guix pull:: Fetching the latest Guix and distribution.
2963 * Invoking guix time-machine:: Running an older revision of Guix.
2964 * Inferiors:: Interacting with another revision of Guix.
2965 * Invoking guix describe:: Display information about your Guix revision.
2966 * Invoking guix archive:: Exporting and importing store files.
2972 Here we assume you've already made your first steps with Guix
2973 (@pxref{Getting Started}) and would like to get an overview about what's
2974 going on under the hood.
2976 When using Guix, each package ends up in the @dfn{package store}, in its
2977 own directory---something that resembles
2978 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2980 Instead of referring to these directories, users have their own
2981 @dfn{profile}, which points to the packages that they actually want to
2982 use. These profiles are stored within each user's home directory, at
2983 @code{$HOME/.guix-profile}.
2985 For example, @code{alice} installs GCC 4.7.2. As a result,
2986 @file{/home/alice/.guix-profile/bin/gcc} points to
2987 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2988 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2989 simply continues to point to
2990 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2991 coexist on the same system without any interference.
2993 The @command{guix package} command is the central tool to manage
2994 packages (@pxref{Invoking guix package}). It operates on the per-user
2995 profiles, and can be used @emph{with normal user privileges}.
2997 @cindex transactions
2998 The command provides the obvious install, remove, and upgrade
2999 operations. Each invocation is actually a @emph{transaction}: either
3000 the specified operation succeeds, or nothing happens. Thus, if the
3001 @command{guix package} process is terminated during the transaction,
3002 or if a power outage occurs during the transaction, then the user's
3003 profile remains in its previous state, and remains usable.
3005 In addition, any package transaction may be @emph{rolled back}. So, if,
3006 for example, an upgrade installs a new version of a package that turns
3007 out to have a serious bug, users may roll back to the previous instance
3008 of their profile, which was known to work well. Similarly, the global
3009 system configuration on Guix is subject to
3010 transactional upgrades and roll-back
3011 (@pxref{Using the Configuration System}).
3013 All packages in the package store may be @emph{garbage-collected}.
3014 Guix can determine which packages are still referenced by user
3015 profiles, and remove those that are provably no longer referenced
3016 (@pxref{Invoking guix gc}). Users may also explicitly remove old
3017 generations of their profile so that the packages they refer to can be
3020 @cindex reproducibility
3021 @cindex reproducible builds
3022 Guix takes a @dfn{purely functional} approach to package
3023 management, as described in the introduction (@pxref{Introduction}).
3024 Each @file{/gnu/store} package directory name contains a hash of all the
3025 inputs that were used to build that package---compiler, libraries, build
3026 scripts, etc. This direct correspondence allows users to make sure a
3027 given package installation matches the current state of their
3028 distribution. It also helps maximize @dfn{build reproducibility}:
3029 thanks to the isolated build environments that are used, a given build
3030 is likely to yield bit-identical files when performed on different
3031 machines (@pxref{Invoking guix-daemon, container}).
3034 This foundation allows Guix to support @dfn{transparent binary/source
3035 deployment}. When a pre-built binary for a @file{/gnu/store} item is
3036 available from an external source---a @dfn{substitute}, Guix just
3037 downloads it and unpacks it;
3038 otherwise, it builds the package from source, locally
3039 (@pxref{Substitutes}). Because build results are usually bit-for-bit
3040 reproducible, users do not have to trust servers that provide
3041 substitutes: they can force a local build and @emph{challenge} providers
3042 (@pxref{Invoking guix challenge}).
3044 Control over the build environment is a feature that is also useful for
3045 developers. The @command{guix environment} command allows developers of
3046 a package to quickly set up the right development environment for their
3047 package, without having to manually install the dependencies of the
3048 package into their profile (@pxref{Invoking guix environment}).
3050 @cindex replication, of software environments
3051 @cindex provenance tracking, of software artifacts
3052 All of Guix and its package definitions is version-controlled, and
3053 @command{guix pull} allows you to ``travel in time'' on the history of Guix
3054 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
3055 Guix instance on a different machine or at a later point in time, which in
3056 turn allows you to @emph{replicate complete software environments}, while
3057 retaining precise @dfn{provenance tracking} of the software.
3059 @node Invoking guix package
3060 @section Invoking @command{guix package}
3062 @cindex installing packages
3063 @cindex removing packages
3064 @cindex package installation
3065 @cindex package removal
3067 The @command{guix package} command is the tool that allows users to
3068 install, upgrade, and remove packages, as well as rolling back to
3069 previous configurations. These operations work on a user
3070 @dfn{profile}---a directory of installed packages. Each user has a
3071 default profile in @file{$HOME/.guix-profile}.
3072 The command operates only on the user's own profile,
3073 and works with normal user privileges (@pxref{Features}). Its syntax
3077 guix package @var{options}
3080 @cindex transactions
3081 Primarily, @var{options} specifies the operations to be performed during
3082 the transaction. Upon completion, a new profile is created, but
3083 previous @dfn{generations} of the profile remain available, should the user
3086 For example, to remove @code{lua} and install @code{guile} and
3087 @code{guile-cairo} in a single transaction:
3090 guix package -r lua -i guile guile-cairo
3093 @cindex aliases, for @command{guix package}
3094 For your convenience, we also provide the following aliases:
3098 @command{guix search} is an alias for @command{guix package -s},
3100 @command{guix install} is an alias for @command{guix package -i},
3102 @command{guix remove} is an alias for @command{guix package -r},
3104 @command{guix upgrade} is an alias for @command{guix package -u},
3106 and @command{guix show} is an alias for @command{guix package --show=}.
3109 These aliases are less expressive than @command{guix package} and provide
3110 fewer options, so in some cases you'll probably want to use @command{guix
3113 @command{guix package} also supports a @dfn{declarative approach}
3114 whereby the user specifies the exact set of packages to be available and
3115 passes it @i{via} the @option{--manifest} option
3116 (@pxref{profile-manifest, @option{--manifest}}).
3119 For each user, a symlink to the user's default profile is automatically
3120 created in @file{$HOME/.guix-profile}. This symlink always points to the
3121 current generation of the user's default profile. Thus, users can add
3122 @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
3123 variable, and so on.
3124 @cindex search paths
3125 If you are not using Guix System, consider adding the
3126 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
3127 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
3128 shells get all the right environment variable definitions:
3131 GUIX_PROFILE="$HOME/.guix-profile" ; \
3132 source "$GUIX_PROFILE/etc/profile"
3135 In a multi-user setup, user profiles are stored in a place registered as
3136 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
3137 to (@pxref{Invoking guix gc}). That directory is normally
3138 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
3139 @var{localstatedir} is the value passed to @code{configure} as
3140 @option{--localstatedir}, and @var{user} is the user name. The
3141 @file{per-user} directory is created when @command{guix-daemon} is
3142 started, and the @var{user} sub-directory is created by @command{guix
3145 The @var{options} can be among the following:
3149 @item --install=@var{package} @dots{}
3150 @itemx -i @var{package} @dots{}
3151 Install the specified @var{package}s.
3153 Each @var{package} may specify either a simple package name, such as
3154 @code{guile}, or a package name followed by an at-sign and version number,
3155 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
3156 case, the newest version prefixed by @code{1.8} is selected).
3158 If no version number is specified, the
3159 newest available version will be selected. In addition, @var{package}
3160 may contain a colon, followed by the name of one of the outputs of the
3161 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
3162 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
3163 name (and optionally version) are searched for among the GNU
3164 distribution modules (@pxref{Package Modules}).
3166 @cindex propagated inputs
3167 Sometimes packages have @dfn{propagated inputs}: these are dependencies
3168 that automatically get installed along with the required package
3169 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
3170 @code{package} objects}, for information about propagated inputs in
3171 package definitions).
3173 @anchor{package-cmd-propagated-inputs}
3174 An example is the GNU MPC library: its C header files refer to those of
3175 the GNU MPFR library, which in turn refer to those of the GMP library.
3176 Thus, when installing MPC, the MPFR and GMP libraries also get installed
3177 in the profile; removing MPC also removes MPFR and GMP---unless they had
3178 also been explicitly installed by the user.
3180 Besides, packages sometimes rely on the definition of environment
3181 variables for their search paths (see explanation of
3182 @option{--search-paths} below). Any missing or possibly incorrect
3183 environment variable definitions are reported here.
3185 @item --install-from-expression=@var{exp}
3187 Install the package @var{exp} evaluates to.
3189 @var{exp} must be a Scheme expression that evaluates to a
3190 @code{<package>} object. This option is notably useful to disambiguate
3191 between same-named variants of a package, with expressions such as
3192 @code{(@@ (gnu packages base) guile-final)}.
3194 Note that this option installs the first output of the specified
3195 package, which may be insufficient when needing a specific output of a
3196 multiple-output package.
3198 @item --install-from-file=@var{file}
3199 @itemx -f @var{file}
3200 Install the package that the code within @var{file} evaluates to.
3202 As an example, @var{file} might contain a definition like this
3203 (@pxref{Defining Packages}):
3206 @include package-hello.scm
3209 Developers may find it useful to include such a @file{guix.scm} file
3210 in the root of their project source tree that can be used to test
3211 development snapshots and create reproducible development environments
3212 (@pxref{Invoking guix environment}).
3214 The @var{file} may also contain a JSON representation of one or more
3215 package definitions. Running @code{guix package -f} on
3216 @file{hello.json} with the following contents would result in installing
3217 the package @code{greeter} after building @code{myhello}:
3220 @verbatiminclude package-hello.json
3223 @item --remove=@var{package} @dots{}
3224 @itemx -r @var{package} @dots{}
3225 Remove the specified @var{package}s.
3227 As for @option{--install}, each @var{package} may specify a version number
3228 and/or output name in addition to the package name. For instance,
3229 @samp{-r glibc:debug} would remove the @code{debug} output of
3232 @item --upgrade[=@var{regexp} @dots{}]
3233 @itemx -u [@var{regexp} @dots{}]
3234 @cindex upgrading packages
3235 Upgrade all the installed packages. If one or more @var{regexp}s are
3236 specified, upgrade only installed packages whose name matches a
3237 @var{regexp}. Also see the @option{--do-not-upgrade} option below.
3239 Note that this upgrades package to the latest version of packages found
3240 in the distribution currently installed. To update your distribution,
3241 you should regularly run @command{guix pull} (@pxref{Invoking guix
3244 @cindex package transformations, upgrades
3245 When upgrading, package transformations that were originally applied
3246 when creating the profile are automatically re-applied (@pxref{Package
3247 Transformation Options}). For example, assume you first installed Emacs
3248 from the tip of its development branch with:
3251 guix install emacs-next --with-branch=emacs-next=master
3254 Next time you run @command{guix upgrade}, Guix will again pull the tip
3255 of the Emacs development branch and build @code{emacs-next} from that
3258 Note that transformation options such as @option{--with-branch} and
3259 @option{--with-source} depend on external state; it is up to you to
3260 ensure that they work as expected. You can also discard a
3261 transformations that apply to a package by running:
3264 guix install @var{package}
3267 @item --do-not-upgrade[=@var{regexp} @dots{}]
3268 When used together with the @option{--upgrade} option, do @emph{not}
3269 upgrade any packages whose name matches a @var{regexp}. For example, to
3270 upgrade all packages in the current profile except those containing the
3271 substring ``emacs'':
3274 $ guix package --upgrade . --do-not-upgrade emacs
3277 @item @anchor{profile-manifest}--manifest=@var{file}
3278 @itemx -m @var{file}
3279 @cindex profile declaration
3280 @cindex profile manifest
3281 Create a new generation of the profile from the manifest object
3282 returned by the Scheme code in @var{file}. This option can be repeated
3283 several times, in which case the manifests are concatenated.
3285 This allows you to @emph{declare} the profile's contents rather than
3286 constructing it through a sequence of @option{--install} and similar
3287 commands. The advantage is that @var{file} can be put under version
3288 control, copied to different machines to reproduce the same profile, and
3291 @c FIXME: Add reference to (guix profile) documentation when available.
3292 @var{file} must return a @dfn{manifest} object, which is roughly a list
3295 @findex packages->manifest
3297 (use-package-modules guile emacs)
3302 ;; Use a specific package output.
3303 (list guile-2.0 "debug")))
3306 @findex specifications->manifest
3307 In this example we have to know which modules define the @code{emacs}
3308 and @code{guile-2.0} variables to provide the right
3309 @code{use-package-modules} line, which can be cumbersome. We can
3310 instead provide regular package specifications and let
3311 @code{specifications->manifest} look up the corresponding package
3315 (specifications->manifest
3316 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
3319 @xref{export-manifest, @option{--export-manifest}}, to learn how to
3320 obtain a manifest file from an existing profile.
3323 @cindex rolling back
3324 @cindex undoing transactions
3325 @cindex transactions, undoing
3326 Roll back to the previous @dfn{generation} of the profile---i.e., undo
3327 the last transaction.
3329 When combined with options such as @option{--install}, roll back occurs
3330 before any other actions.
3332 When rolling back from the first generation that actually contains
3333 installed packages, the profile is made to point to the @dfn{zeroth
3334 generation}, which contains no files apart from its own metadata.
3336 After having rolled back, installing, removing, or upgrading packages
3337 overwrites previous future generations. Thus, the history of the
3338 generations in a profile is always linear.
3340 @item --switch-generation=@var{pattern}
3341 @itemx -S @var{pattern}
3343 Switch to a particular generation defined by @var{pattern}.
3345 @var{pattern} may be either a generation number or a number prefixed
3346 with ``+'' or ``-''. The latter means: move forward/backward by a
3347 specified number of generations. For example, if you want to return to
3348 the latest generation after @option{--roll-back}, use
3349 @option{--switch-generation=+1}.
3351 The difference between @option{--roll-back} and
3352 @option{--switch-generation=-1} is that @option{--switch-generation} will
3353 not make a zeroth generation, so if a specified generation does not
3354 exist, the current generation will not be changed.
3356 @item --search-paths[=@var{kind}]
3357 @cindex search paths
3358 Report environment variable definitions, in Bash syntax, that may be
3359 needed in order to use the set of installed packages. These environment
3360 variables are used to specify @dfn{search paths} for files used by some
3361 of the installed packages.
3363 For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
3364 environment variables to be defined so it can look for headers and
3365 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
3366 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
3367 library are installed in the profile, then @option{--search-paths} will
3368 suggest setting these variables to @file{@var{profile}/include} and
3369 @file{@var{profile}/lib}, respectively.
3371 The typical use case is to define these environment variables in the
3375 $ eval `guix package --search-paths`
3378 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
3379 meaning that the returned environment variable definitions will either
3380 be exact settings, or prefixes or suffixes of the current value of these
3381 variables. When omitted, @var{kind} defaults to @code{exact}.
3383 This option can also be used to compute the @emph{combined} search paths
3384 of several profiles. Consider this example:
3387 $ guix package -p foo -i guile
3388 $ guix package -p bar -i guile-json
3389 $ guix package -p foo -p bar --search-paths
3392 The last command above reports about the @env{GUILE_LOAD_PATH}
3393 variable, even though, taken individually, neither @file{foo} nor
3394 @file{bar} would lead to that recommendation.
3397 @cindex profile, choosing
3398 @item --profile=@var{profile}
3399 @itemx -p @var{profile}
3400 Use @var{profile} instead of the user's default profile.
3402 @var{profile} must be the name of a file that will be created upon
3403 completion. Concretely, @var{profile} will be a mere symbolic link
3404 (``symlink'') pointing to the actual profile where packages are
3408 $ guix install hello -p ~/code/my-profile
3410 $ ~/code/my-profile/bin/hello
3414 All it takes to get rid of the profile is to remove this symlink and its
3415 siblings that point to specific generations:
3418 $ rm ~/code/my-profile ~/code/my-profile-*-link
3421 @item --list-profiles
3422 List all the user's profiles:
3425 $ guix package --list-profiles
3426 /home/charlie/.guix-profile
3427 /home/charlie/code/my-profile
3428 /home/charlie/code/devel-profile
3429 /home/charlie/tmp/test
3432 When running as root, list all the profiles of all the users.
3434 @cindex collisions, in a profile
3435 @cindex colliding packages in profiles
3436 @cindex profile collisions
3437 @item --allow-collisions
3438 Allow colliding packages in the new profile. Use at your own risk!
3440 By default, @command{guix package} reports as an error @dfn{collisions}
3441 in the profile. Collisions happen when two or more different versions
3442 or variants of a given package end up in the profile.
3445 Use the bootstrap Guile to build the profile. This option is only
3446 useful to distribution developers.
3450 In addition to these actions, @command{guix package} supports the
3451 following options to query the current state of a profile, or the
3452 availability of packages:
3456 @item --search=@var{regexp}
3457 @itemx -s @var{regexp}
3458 @anchor{guix-search}
3459 @cindex searching for packages
3460 List the available packages whose name, synopsis, or description matches
3461 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3462 Print all the metadata of matching packages in
3463 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3464 GNU recutils manual}).
3466 This allows specific fields to be extracted using the @command{recsel}
3467 command, for instance:
3470 $ guix package -s malloc | recsel -p name,version,relevance
3484 Similarly, to show the name of all the packages available under the
3485 terms of the GNU@tie{}LGPL version 3:
3488 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3495 It is also possible to refine search results using several @code{-s} flags to
3496 @command{guix package}, or several arguments to @command{guix search}. For
3497 example, the following command returns a list of board games (this time using
3498 the @command{guix search} alias):
3501 $ guix search '\<board\>' game | recsel -p name
3506 If we were to omit @code{-s game}, we would also get software packages
3507 that deal with printed circuit boards; removing the angle brackets
3508 around @code{board} would further add packages that have to do with
3511 And now for a more elaborate example. The following command searches
3512 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3513 libraries, and prints the name and synopsis of the matching packages:
3516 $ guix search crypto library | \
3517 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3521 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3522 information on @dfn{selection expressions} for @code{recsel -e}.
3524 @item --show=@var{package}
3525 Show details about @var{package}, taken from the list of available packages, in
3526 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3530 $ guix package --show=python | recsel -p name,version
3538 You may also specify the full name of a package to only get details about a
3539 specific version of it (this time using the @command{guix show} alias):
3541 $ guix show python@@3.4 | recsel -p name,version
3548 @item --list-installed[=@var{regexp}]
3549 @itemx -I [@var{regexp}]
3550 List the currently installed packages in the specified profile, with the
3551 most recently installed packages shown last. When @var{regexp} is
3552 specified, list only installed packages whose name matches @var{regexp}.
3554 For each installed package, print the following items, separated by
3555 tabs: the package name, its version string, the part of the package that
3556 is installed (for instance, @code{out} for the default output,
3557 @code{include} for its headers, etc.), and the path of this package in
3560 @item --list-available[=@var{regexp}]
3561 @itemx -A [@var{regexp}]
3562 List packages currently available in the distribution for this system
3563 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3564 available packages whose name matches @var{regexp}.
3566 For each package, print the following items separated by tabs: its name,
3567 its version string, the parts of the package (@pxref{Packages with
3568 Multiple Outputs}), and the source location of its definition.
3570 @item --list-generations[=@var{pattern}]
3571 @itemx -l [@var{pattern}]
3573 Return a list of generations along with their creation dates; for each
3574 generation, show the installed packages, with the most recently
3575 installed packages shown last. Note that the zeroth generation is never
3578 For each installed package, print the following items, separated by
3579 tabs: the name of a package, its version string, the part of the package
3580 that is installed (@pxref{Packages with Multiple Outputs}), and the
3581 location of this package in the store.
3583 When @var{pattern} is used, the command returns only matching
3584 generations. Valid patterns include:
3587 @item @emph{Integers and comma-separated integers}. Both patterns denote
3588 generation numbers. For instance, @option{--list-generations=1} returns
3591 And @option{--list-generations=1,8,2} outputs three generations in the
3592 specified order. Neither spaces nor trailing commas are allowed.
3594 @item @emph{Ranges}. @option{--list-generations=2..9} prints the
3595 specified generations and everything in between. Note that the start of
3596 a range must be smaller than its end.
3598 It is also possible to omit the endpoint. For example,
3599 @option{--list-generations=2..}, returns all generations starting from the
3602 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3603 or months by passing an integer along with the first letter of the
3604 duration. For example, @option{--list-generations=20d} lists generations
3605 that are up to 20 days old.
3608 @item --delete-generations[=@var{pattern}]
3609 @itemx -d [@var{pattern}]
3610 When @var{pattern} is omitted, delete all generations except the current
3613 This command accepts the same patterns as @option{--list-generations}.
3614 When @var{pattern} is specified, delete the matching generations. When
3615 @var{pattern} specifies a duration, generations @emph{older} than the
3616 specified duration match. For instance, @option{--delete-generations=1m}
3617 deletes generations that are more than one month old.
3619 If the current generation matches, it is @emph{not} deleted. Also, the
3620 zeroth generation is never deleted.
3622 Note that deleting generations prevents rolling back to them.
3623 Consequently, this command must be used with care.
3625 @cindex manifest, exporting
3626 @anchor{export-manifest}
3627 @item --export-manifest
3628 Write to standard output a manifest suitable for @option{--manifest}
3629 corresponding to the chosen profile(s).
3631 This option is meant to help you migrate from the ``imperative''
3632 operating mode---running @command{guix install}, @command{guix upgrade},
3633 etc.---to the declarative mode that @option{--manifest} offers.
3635 Be aware that the resulting manifest @emph{approximates} what your
3636 profile actually contains; for instance, depending on how your profile
3637 was created, it can refer to packages or package versions that are not
3638 exactly what you specified.
3640 Keep in mind that a manifest is purely symbolic: it only contains
3641 package names and possibly versions, and their meaning varies over time.
3642 If you wish to ``pin'' channels to the revisions that were used to build
3643 the profile(s), see @option{--export-channels} below.
3645 @cindex pinning, channel revisions of a profile
3646 @item --export-channels
3647 Write to standard output the list of channels used by the chosen
3648 profile(s), in a format suitable for @command{guix pull --channels} or
3649 @command{guix time-machine --channels} (@pxref{Channels}).
3651 Together with @option{--export-manifest}, this option provides
3652 information allowing you to replicate the current profile
3653 (@pxref{Replicating Guix}).
3655 However, note that the output of this command @emph{approximates} what
3656 was actually used to build this profile. In particular, a single
3657 profile might have been built from several different revisions of the
3658 same channel. In that case, @option{--export-manifest} chooses the last
3659 one and writes the list of other revisions in a comment. If you really
3660 need to pick packages from different channel revisions, you can use
3661 inferiors in your manifest to do so (@pxref{Inferiors}).
3663 Together with @option{--export-manifest}, this is a good starting point
3664 if you are willing to migrate from the ``imperative'' model to the fully
3665 declarative model consisting of a manifest file along with a channels
3666 file pinning the exact channel revision(s) you want.
3669 Finally, since @command{guix package} may actually start build
3670 processes, it supports all the common build options (@pxref{Common Build
3671 Options}). It also supports package transformation options, such as
3672 @option{--with-source}, and preserves them across upgrades
3673 (@pxref{Package Transformation Options}).
3676 @section Substitutes
3679 @cindex pre-built binaries
3680 Guix supports transparent source/binary deployment, which means that it
3681 can either build things locally, or download pre-built items from a
3682 server, or both. We call these pre-built items @dfn{substitutes}---they
3683 are substitutes for local build results. In many cases, downloading a
3684 substitute is much faster than building things locally.
3686 Substitutes can be anything resulting from a derivation build
3687 (@pxref{Derivations}). Of course, in the common case, they are
3688 pre-built package binaries, but source tarballs, for instance, which
3689 also result from derivation builds, can be available as substitutes.
3692 * Official Substitute Servers:: One particular source of substitutes.
3693 * Substitute Server Authorization:: How to enable or disable substitutes.
3694 * Getting Substitutes from Other Servers:: Substitute diversity.
3695 * Substitute Authentication:: How Guix verifies substitutes.
3696 * Proxy Settings:: How to get substitutes via proxy.
3697 * Substitution Failure:: What happens when substitution fails.
3698 * On Trusting Binaries:: How can you trust that binary blob?
3701 @node Official Substitute Servers
3702 @subsection Official Substitute Servers
3705 @code{@value{SUBSTITUTE-SERVER-1}} and
3706 @code{@value{SUBSTITUTE-SERVER-2}} are both front-ends to official build
3707 farms that build packages from Guix continuously for some architectures,
3708 and make them available as substitutes. These are the default source of
3709 substitutes; which can be overridden by passing the
3710 @option{--substitute-urls} option either to @command{guix-daemon}
3711 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3712 or to client tools such as @command{guix package}
3713 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3716 Substitute URLs can be either HTTP or HTTPS.
3717 HTTPS is recommended because communications are encrypted; conversely,
3718 using HTTP makes all communications visible to an eavesdropper, who
3719 could use the information gathered to determine, for instance, whether
3720 your system has unpatched security vulnerabilities.
3722 Substitutes from the official build farms are enabled by default when
3723 using Guix System (@pxref{GNU Distribution}). However,
3724 they are disabled by default when using Guix on a foreign distribution,
3725 unless you have explicitly enabled them via one of the recommended
3726 installation steps (@pxref{Installation}). The following paragraphs
3727 describe how to enable or disable substitutes for the official build
3728 farm; the same procedure can also be used to enable substitutes for any
3729 other substitute server.
3731 @node Substitute Server Authorization
3732 @subsection Substitute Server Authorization
3735 @cindex substitutes, authorization thereof
3736 @cindex access control list (ACL), for substitutes
3737 @cindex ACL (access control list), for substitutes
3738 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER-1}}, @code{@value{SUBSTITUTE-SERVER-2}} or a mirror, you
3739 must add the relevant public key to the access control list (ACL) of archive
3740 imports, using the @command{guix archive} command (@pxref{Invoking guix
3741 archive}). Doing so implies that you trust the substitute server to not
3742 be compromised and to serve genuine substitutes.
3745 If you are using Guix System, you can skip this section: Guix System
3746 authorizes substitutes from @code{@value{SUBSTITUTE-SERVER-1}} and
3747 @code{@value{SUBSTITUTE-SERVER-2}} by default.
3750 The public keys for each of the project maintained substitute servers
3751 are installed along with Guix, in @code{@var{prefix}/share/guix/}, where
3752 @var{prefix} is the installation prefix of Guix. If you installed Guix
3753 from source, make sure you checked the GPG signature of
3754 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3755 Then, you can run something like this:
3758 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
3759 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
3762 Once this is in place, the output of a command like @code{guix build}
3763 should change from something like:
3766 $ guix build emacs --dry-run
3767 The following derivations would be built:
3768 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3769 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3770 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3771 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3779 $ guix build emacs --dry-run
3780 112.3 MB would be downloaded:
3781 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3782 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3783 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3784 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3789 The text changed from ``The following derivations would be built'' to
3790 ``112.3 MB would be downloaded''. This indicates that substitutes from
3791 the configured substitute servers are usable and will be downloaded,
3792 when possible, for future builds.
3794 @cindex substitutes, how to disable
3795 The substitute mechanism can be disabled globally by running
3796 @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
3797 guix-daemon}). It can also be disabled temporarily by passing the
3798 @option{--no-substitutes} option to @command{guix package},
3799 @command{guix build}, and other command-line tools.
3801 @node Getting Substitutes from Other Servers
3802 @subsection Getting Substitutes from Other Servers
3804 @cindex substitute servers, adding more
3805 Guix can look up and fetch substitutes from several servers. This is
3806 useful when you are using packages from additional channels for which
3807 the official server does not have substitutes but another server
3808 provides them. Another situation where this is useful is when you would
3809 prefer to download from your organization's substitute server, resorting
3810 to the official server only as a fallback or dismissing it altogether.
3812 You can give Guix a list of substitute server URLs and it will check
3813 them in the specified order. You also need to explicitly authorize the
3814 public keys of substitute servers to instruct Guix to accept the
3815 substitutes they sign.
3817 On Guix System, this is achieved by modifying the configuration of the
3818 @code{guix} service. Since the @code{guix} service is part of the
3819 default lists of services, @code{%base-services} and
3820 @code{%desktop-services}, you can use @code{modify-services} to change
3821 its configuration and add the URLs and substitute keys that you want
3822 (@pxref{Service Reference, @code{modify-services}}).
3824 As an example, suppose you want to fetch substitutes from
3825 @code{guix.example.org} and to authorize the signing key of that server,
3826 in addition to the default @code{@value{SUBSTITUTE-SERVER-1}} and
3827 @code{@value{SUBSTITUTE-SERVER-2}}. The resulting operating system
3828 configuration will look something like:
3834 ;; Assume we're starting from '%desktop-services'. Replace it
3835 ;; with the list of services you're actually using.
3836 (modify-services %desktop-services
3837 (guix-service-type config =>
3841 (append (list "https://guix.example.org")
3842 %default-substitute-urls))
3844 (append (list (local-file "./key.pub"))
3845 %default-authorized-guix-keys)))))))
3848 This assumes that the file @file{key.pub} contains the signing key of
3849 @code{guix.example.org}. With this change in place in your operating
3850 system configuration file (say @file{/etc/config.scm}), you can
3851 reconfigure and restart the @code{guix-daemon} service or reboot so the
3852 changes take effect:
3855 $ sudo guix system reconfigure /etc/config.scm
3856 $ sudo herd restart guix-daemon
3859 If you're running Guix on a ``foreign distro'', you would instead take
3860 the following steps to get substitutes from additional servers:
3864 Edit the service configuration file for @code{guix-daemon}; when using
3865 systemd, this is normally
3866 @file{/etc/systemd/system/guix-daemon.service}. Add the
3867 @option{--substitute-urls} option on the @command{guix-daemon} command
3868 line and list the URLs of interest (@pxref{daemon-substitute-urls,
3869 @code{guix-daemon --substitute-urls}}):
3872 @dots{} --substitute-urls='https://guix.example.org @value{SUBSTITUTE-URLS}'
3876 Restart the daemon. For systemd, it goes like this:
3879 systemctl daemon-reload
3880 systemctl restart guix-daemon.service
3884 Authorize the key of the new server (@pxref{Invoking guix archive}):
3887 guix archive --authorize < key.pub
3890 Again this assumes @file{key.pub} contains the public key that
3891 @code{guix.example.org} uses to sign substitutes.
3894 Now you're all set! Substitutes will be preferably taken from
3895 @code{https://guix.example.org}, using
3896 @code{@value{SUBSTITUTE-SERVER-1}} then
3897 @code{@value{SUBSTITUTE-SERVER-2}} as fallback options. Of course you
3898 can list as many substitute servers as you like, with the caveat that
3899 substitute lookup can be slowed down if too many servers need to be
3902 Note that there are also situations where one may want to add the URL of
3903 a substitute server @emph{without} authorizing its key.
3904 @xref{Substitute Authentication}, to understand this fine point.
3906 @node Substitute Authentication
3907 @subsection Substitute Authentication
3909 @cindex digital signatures
3910 Guix detects and raises an error when attempting to use a substitute
3911 that has been tampered with. Likewise, it ignores substitutes that are
3912 not signed, or that are not signed by one of the keys listed in the ACL.
3914 There is one exception though: if an unauthorized server provides
3915 substitutes that are @emph{bit-for-bit identical} to those provided by
3916 an authorized server, then the unauthorized server becomes eligible for
3917 downloads. For example, assume we have chosen two substitute servers
3921 --substitute-urls="https://a.example.org https://b.example.org"
3925 @cindex reproducible builds
3926 If the ACL contains only the key for @samp{b.example.org}, and if
3927 @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
3928 then Guix will download substitutes from @samp{a.example.org} because it
3929 comes first in the list and can be considered a mirror of
3930 @samp{b.example.org}. In practice, independent build machines usually
3931 produce the same binaries, thanks to bit-reproducible builds (see
3934 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3935 (in other words, the server is not authenticated), contrary to what
3936 HTTPS clients such as Web browsers usually do. This is because Guix
3937 authenticates substitute information itself, as explained above, which
3938 is what we care about (whereas X.509 certificates are about
3939 authenticating bindings between domain names and public keys).
3941 @node Proxy Settings
3942 @subsection Proxy Settings
3946 Substitutes are downloaded over HTTP or HTTPS@. The @env{http_proxy} and
3947 @env{https_proxy} environment variables can be set in the environment of
3948 @command{guix-daemon} and are honored for downloads of substitutes.
3949 Note that the value of those environment variables in the environment
3950 where @command{guix build}, @command{guix package}, and other client
3951 commands are run has @emph{absolutely no effect}.
3953 @node Substitution Failure
3954 @subsection Substitution Failure
3956 Even when a substitute for a derivation is available, sometimes the
3957 substitution attempt will fail. This can happen for a variety of
3958 reasons: the substitute server might be offline, the substitute may
3959 recently have been deleted, the connection might have been interrupted,
3962 When substitutes are enabled and a substitute for a derivation is
3963 available, but the substitution attempt fails, Guix will attempt to
3964 build the derivation locally depending on whether or not
3965 @option{--fallback} was given (@pxref{fallback-option,, common build
3966 option @option{--fallback}}). Specifically, if @option{--fallback} was
3967 omitted, then no local build will be performed, and the derivation is
3968 considered to have failed. However, if @option{--fallback} was given,
3969 then Guix will attempt to build the derivation locally, and the success
3970 or failure of the derivation depends on the success or failure of the
3971 local build. Note that when substitutes are disabled or no substitute
3972 is available for the derivation in question, a local build will
3973 @emph{always} be performed, regardless of whether or not
3974 @option{--fallback} was given.
3976 To get an idea of how many substitutes are available right now, you can
3977 try running the @command{guix weather} command (@pxref{Invoking guix
3978 weather}). This command provides statistics on the substitutes provided
3981 @node On Trusting Binaries
3982 @subsection On Trusting Binaries
3984 @cindex trust, of pre-built binaries
3985 Today, each individual's control over their own computing is at the
3986 mercy of institutions, corporations, and groups with enough power and
3987 determination to subvert the computing infrastructure and exploit its
3988 weaknesses. While using substitutes can be convenient, we encourage
3989 users to also build on their own, or even run their own build farm, such
3990 that the project run substitute servers are less of an interesting
3991 target. One way to help is by publishing the software you build using
3992 @command{guix publish} so that others have one more choice of server to
3993 download substitutes from (@pxref{Invoking guix publish}).
3995 Guix has the foundations to maximize build reproducibility
3996 (@pxref{Features}). In most cases, independent builds of a given
3997 package or derivation should yield bit-identical results. Thus, through
3998 a diverse set of independent package builds, we can strengthen the
3999 integrity of our systems. The @command{guix challenge} command aims to
4000 help users assess substitute servers, and to assist developers in
4001 finding out about non-deterministic package builds (@pxref{Invoking guix
4002 challenge}). Similarly, the @option{--check} option of @command{guix
4003 build} allows users to check whether previously-installed substitutes
4004 are genuine by rebuilding them locally (@pxref{build-check,
4005 @command{guix build --check}}).
4007 In the future, we want Guix to have support to publish and retrieve
4008 binaries to/from other users, in a peer-to-peer fashion. If you would
4009 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
4011 @node Packages with Multiple Outputs
4012 @section Packages with Multiple Outputs
4014 @cindex multiple-output packages
4015 @cindex package outputs
4018 Often, packages defined in Guix have a single @dfn{output}---i.e., the
4019 source package leads to exactly one directory in the store. When running
4020 @command{guix install glibc}, one installs the default output of the
4021 GNU libc package; the default output is called @code{out}, but its name
4022 can be omitted as shown in this command. In this particular case, the
4023 default output of @code{glibc} contains all the C header files, shared
4024 libraries, static libraries, Info documentation, and other supporting
4027 Sometimes it is more appropriate to separate the various types of files
4028 produced from a single source package into separate outputs. For
4029 instance, the GLib C library (used by GTK+ and related packages)
4030 installs more than 20 MiB of reference documentation as HTML pages.
4031 To save space for users who do not need it, the documentation goes to a
4032 separate output, called @code{doc}. To install the main GLib output,
4033 which contains everything but the documentation, one would run:
4039 @cindex documentation
4040 The command to install its documentation is:
4043 guix install glib:doc
4046 Some packages install programs with different ``dependency footprints''.
4047 For instance, the WordNet package installs both command-line tools and
4048 graphical user interfaces (GUIs). The former depend solely on the C
4049 library, whereas the latter depend on Tcl/Tk and the underlying X
4050 libraries. In this case, we leave the command-line tools in the default
4051 output, whereas the GUIs are in a separate output. This allows users
4052 who do not need the GUIs to save space. The @command{guix size} command
4053 can help find out about such situations (@pxref{Invoking guix size}).
4054 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
4056 There are several such multiple-output packages in the GNU distribution.
4057 Other conventional output names include @code{lib} for libraries and
4058 possibly header files, @code{bin} for stand-alone programs, and
4059 @code{debug} for debugging information (@pxref{Installing Debugging
4060 Files}). The outputs of a packages are listed in the third column of
4061 the output of @command{guix package --list-available} (@pxref{Invoking
4065 @node Invoking guix gc
4066 @section Invoking @command{guix gc}
4068 @cindex garbage collector
4070 Packages that are installed, but not used, may be @dfn{garbage-collected}.
4071 The @command{guix gc} command allows users to explicitly run the garbage
4072 collector to reclaim space from the @file{/gnu/store} directory. It is
4073 the @emph{only} way to remove files from @file{/gnu/store}---removing
4074 files or directories manually may break it beyond repair!
4077 @cindex garbage collector roots
4078 The garbage collector has a set of known @dfn{roots}: any file under
4079 @file{/gnu/store} reachable from a root is considered @dfn{live} and
4080 cannot be deleted; any other file is considered @dfn{dead} and may be
4081 deleted. The set of garbage collector roots (``GC roots'' for short)
4082 includes default user profiles; by default, the symlinks under
4083 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
4084 added with @command{guix build --root}, for example (@pxref{Invoking
4085 guix build}). The @command{guix gc --list-roots} command lists them.
4087 Prior to running @code{guix gc --collect-garbage} to make space, it is
4088 often useful to remove old generations from user profiles; that way, old
4089 package builds referenced by those generations can be reclaimed. This
4090 is achieved by running @code{guix package --delete-generations}
4091 (@pxref{Invoking guix package}).
4093 Our recommendation is to run a garbage collection periodically, or when
4094 you are short on disk space. For instance, to guarantee that at least
4095 5@tie{}GB are available on your disk, simply run:
4101 It is perfectly safe to run as a non-interactive periodic job
4102 (@pxref{Scheduled Job Execution}, for how to set up such a job).
4103 Running @command{guix gc} with no arguments will collect as
4104 much garbage as it can, but that is often inconvenient: you may find
4105 yourself having to rebuild or re-download software that is ``dead'' from
4106 the GC viewpoint but that is necessary to build other pieces of
4107 software---e.g., the compiler tool chain.
4109 The @command{guix gc} command has three modes of operation: it can be
4110 used to garbage-collect any dead files (the default), to delete specific
4111 files (the @option{--delete} option), to print garbage-collector
4112 information, or for more advanced queries. The garbage collection
4113 options are as follows:
4116 @item --collect-garbage[=@var{min}]
4117 @itemx -C [@var{min}]
4118 Collect garbage---i.e., unreachable @file{/gnu/store} files and
4119 sub-directories. This is the default operation when no option is
4122 When @var{min} is given, stop once @var{min} bytes have been collected.
4123 @var{min} may be a number of bytes, or it may include a unit as a
4124 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
4125 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
4127 When @var{min} is omitted, collect all the garbage.
4129 @item --free-space=@var{free}
4130 @itemx -F @var{free}
4131 Collect garbage until @var{free} space is available under
4132 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
4133 as @code{500MiB}, as described above.
4135 When @var{free} or more is already available in @file{/gnu/store}, do
4136 nothing and exit immediately.
4138 @item --delete-generations[=@var{duration}]
4139 @itemx -d [@var{duration}]
4140 Before starting the garbage collection process, delete all the generations
4141 older than @var{duration}, for all the user profiles; when run as root, this
4142 applies to all the profiles @emph{of all the users}.
4144 For example, this command deletes all the generations of all your profiles
4145 that are older than 2 months (except generations that are current), and then
4146 proceeds to free space until at least 10 GiB are available:
4149 guix gc -d 2m -F 10G
4154 Attempt to delete all the store files and directories specified as
4155 arguments. This fails if some of the files are not in the store, or if
4156 they are still live.
4158 @item --list-failures
4159 List store items corresponding to cached build failures.
4161 This prints nothing unless the daemon was started with
4162 @option{--cache-failures} (@pxref{Invoking guix-daemon,
4163 @option{--cache-failures}}).
4166 List the GC roots owned by the user; when run as root, list @emph{all} the GC
4170 List store items in use by currently running processes. These store
4171 items are effectively considered GC roots: they cannot be deleted.
4173 @item --clear-failures
4174 Remove the specified store items from the failed-build cache.
4176 Again, this option only makes sense when the daemon is started with
4177 @option{--cache-failures}. Otherwise, it does nothing.
4180 Show the list of dead files and directories still present in the
4181 store---i.e., files and directories no longer reachable from any root.
4184 Show the list of live store files and directories.
4188 In addition, the references among existing store files can be queried:
4194 @cindex package dependencies
4195 List the references (respectively, the referrers) of store files given
4201 List the requisites of the store files passed as arguments. Requisites
4202 include the store files themselves, their references, and the references
4203 of these, recursively. In other words, the returned list is the
4204 @dfn{transitive closure} of the store files.
4206 @xref{Invoking guix size}, for a tool to profile the size of the closure
4207 of an element. @xref{Invoking guix graph}, for a tool to visualize
4208 the graph of references.
4212 Return the derivation(s) leading to the given store items
4213 (@pxref{Derivations}).
4215 For example, this command:
4218 guix gc --derivers $(guix package -I ^emacs$ | cut -f4)
4222 returns the @file{.drv} file(s) leading to the @code{emacs} package
4223 installed in your profile.
4225 Note that there may be zero matching @file{.drv} files, for instance
4226 because these files have been garbage-collected. There can also be more
4227 than one matching @file{.drv} due to fixed-output derivations.
4230 Lastly, the following options allow you to check the integrity of the
4231 store and to control disk usage.
4235 @item --verify[=@var{options}]
4236 @cindex integrity, of the store
4237 @cindex integrity checking
4238 Verify the integrity of the store.
4240 By default, make sure that all the store items marked as valid in the
4241 database of the daemon actually exist in @file{/gnu/store}.
4243 When provided, @var{options} must be a comma-separated list containing one
4244 or more of @code{contents} and @code{repair}.
4246 When passing @option{--verify=contents}, the daemon computes the
4247 content hash of each store item and compares it against its hash in the
4248 database. Hash mismatches are reported as data corruptions. Because it
4249 traverses @emph{all the files in the store}, this command can take a
4250 long time, especially on systems with a slow disk drive.
4252 @cindex repairing the store
4253 @cindex corruption, recovering from
4254 Using @option{--verify=repair} or @option{--verify=contents,repair}
4255 causes the daemon to try to repair corrupt store items by fetching
4256 substitutes for them (@pxref{Substitutes}). Because repairing is not
4257 atomic, and thus potentially dangerous, it is available only to the
4258 system administrator. A lightweight alternative, when you know exactly
4259 which items in the store are corrupt, is @command{guix build --repair}
4260 (@pxref{Invoking guix build}).
4263 @cindex deduplication
4264 Optimize the store by hard-linking identical files---this is
4265 @dfn{deduplication}.
4267 The daemon performs deduplication after each successful build or archive
4268 import, unless it was started with @option{--disable-deduplication}
4269 (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
4270 this option is primarily useful when the daemon was running with
4271 @option{--disable-deduplication}.
4275 @node Invoking guix pull
4276 @section Invoking @command{guix pull}
4278 @cindex upgrading Guix
4279 @cindex updating Guix
4280 @cindex @command{guix pull}
4282 @cindex security, @command{guix pull}
4283 @cindex authenticity, of code obtained with @command{guix pull}
4284 Packages are installed or upgraded to the latest version available in
4285 the distribution currently available on your local machine. To update
4286 that distribution, along with the Guix tools, you must run @command{guix
4287 pull}: the command downloads the latest Guix source code and package
4288 descriptions, and deploys it. Source code is downloaded from a
4289 @uref{https://git-scm.com, Git} repository, by default the official
4290 GNU@tie{}Guix repository, though this can be customized. @command{guix
4291 pull} ensures that the code it downloads is @emph{authentic} by
4292 verifying that commits are signed by Guix developers.
4294 Specifically, @command{guix pull} downloads code from the @dfn{channels}
4295 (@pxref{Channels}) specified by one of the followings, in this order:
4299 the @option{--channels} option;
4301 the user's @file{~/.config/guix/channels.scm} file;
4303 the system-wide @file{/etc/guix/channels.scm} file;
4305 the built-in default channels specified in the @code{%default-channels}
4309 On completion, @command{guix package} will use packages and package
4310 versions from this just-retrieved copy of Guix. Not only that, but all
4311 the Guix commands and Scheme modules will also be taken from that latest
4312 version. New @command{guix} sub-commands added by the update also
4315 Any user can update their Guix copy using @command{guix pull}, and the
4316 effect is limited to the user who ran @command{guix pull}. For
4317 instance, when user @code{root} runs @command{guix pull}, this has no
4318 effect on the version of Guix that user @code{alice} sees, and vice
4321 The result of running @command{guix pull} is a @dfn{profile} available
4322 under @file{~/.config/guix/current} containing the latest Guix. Thus,
4323 make sure to add it to the beginning of your search path so that you use
4324 the latest version, and similarly for the Info manual
4325 (@pxref{Documentation}):
4328 export PATH="$HOME/.config/guix/current/bin:$PATH"
4329 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
4332 The @option{--list-generations} or @option{-l} option lists past generations
4333 produced by @command{guix pull}, along with details about their provenance:
4337 Generation 1 Jun 10 2018 00:18:18
4339 repository URL: https://git.savannah.gnu.org/git/guix.git
4340 branch: origin/master
4341 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
4343 Generation 2 Jun 11 2018 11:02:49
4345 repository URL: https://git.savannah.gnu.org/git/guix.git
4346 branch: origin/master
4347 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
4348 2 new packages: keepalived, libnfnetlink
4349 6 packages upgraded: emacs-nix-mode@@2.0.4,
4350 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
4351 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
4353 Generation 3 Jun 13 2018 23:31:07 (current)
4355 repository URL: https://git.savannah.gnu.org/git/guix.git
4356 branch: origin/master
4357 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
4358 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
4359 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
4362 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
4363 describe the current status of Guix.
4365 This @code{~/.config/guix/current} profile works exactly like the profiles
4366 created by @command{guix package} (@pxref{Invoking guix package}). That
4367 is, you can list generations, roll back to the previous
4368 generation---i.e., the previous Guix---and so on:
4371 $ guix pull --roll-back
4372 switched from generation 3 to 2
4373 $ guix pull --delete-generations=1
4374 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4377 You can also use @command{guix package} (@pxref{Invoking guix package})
4378 to manage the profile by naming it explicitly:
4380 $ guix package -p ~/.config/guix/current --roll-back
4381 switched from generation 3 to 2
4382 $ guix package -p ~/.config/guix/current --delete-generations=1
4383 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4386 The @command{guix pull} command is usually invoked with no arguments,
4387 but it supports the following options:
4390 @item --url=@var{url}
4391 @itemx --commit=@var{commit}
4392 @itemx --branch=@var{branch}
4393 Download code for the @code{guix} channel from the specified @var{url}, at the
4394 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4395 string), or @var{branch}.
4397 @cindex @file{channels.scm}, configuration file
4398 @cindex configuration file for channels
4399 These options are provided for convenience, but you can also specify your
4400 configuration in the @file{~/.config/guix/channels.scm} file or using the
4401 @option{--channels} option (see below).
4403 @item --channels=@var{file}
4404 @itemx -C @var{file}
4405 Read the list of channels from @var{file} instead of
4406 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
4407 @var{file} must contain Scheme code that
4408 evaluates to a list of channel objects. @xref{Channels}, for more
4411 @cindex channel news
4414 Display the list of packages added or upgraded since the previous
4415 generation, as well as, occasionally, news written by channel authors
4416 for their users (@pxref{Channels, Writing Channel News}).
4418 The package information is the same as displayed upon @command{guix
4419 pull} completion, but without ellipses; it is also similar to the output
4420 of @command{guix pull -l} for the last generation (see below).
4422 @item --list-generations[=@var{pattern}]
4423 @itemx -l [@var{pattern}]
4424 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
4425 is provided, the subset of generations that match @var{pattern}.
4426 The syntax of @var{pattern} is the same as with @code{guix package
4427 --list-generations} (@pxref{Invoking guix package}).
4430 @cindex rolling back
4431 @cindex undoing transactions
4432 @cindex transactions, undoing
4433 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
4434 undo the last transaction.
4436 @item --switch-generation=@var{pattern}
4437 @itemx -S @var{pattern}
4439 Switch to a particular generation defined by @var{pattern}.
4441 @var{pattern} may be either a generation number or a number prefixed
4442 with ``+'' or ``-''. The latter means: move forward/backward by a
4443 specified number of generations. For example, if you want to return to
4444 the latest generation after @option{--roll-back}, use
4445 @option{--switch-generation=+1}.
4447 @item --delete-generations[=@var{pattern}]
4448 @itemx -d [@var{pattern}]
4449 When @var{pattern} is omitted, delete all generations except the current
4452 This command accepts the same patterns as @option{--list-generations}.
4453 When @var{pattern} is specified, delete the matching generations. When
4454 @var{pattern} specifies a duration, generations @emph{older} than the
4455 specified duration match. For instance, @option{--delete-generations=1m}
4456 deletes generations that are more than one month old.
4458 If the current generation matches, it is @emph{not} deleted.
4460 Note that deleting generations prevents rolling back to them.
4461 Consequently, this command must be used with care.
4463 @xref{Invoking guix describe}, for a way to display information about the
4464 current generation only.
4466 @item --profile=@var{profile}
4467 @itemx -p @var{profile}
4468 Use @var{profile} instead of @file{~/.config/guix/current}.
4472 Show which channel commit(s) would be used and what would be built or
4473 substituted but do not actually do it.
4475 @item --allow-downgrades
4476 Allow pulling older or unrelated revisions of channels than those
4479 @cindex downgrade attacks, protection against
4480 By default, @command{guix pull} protects against so-called ``downgrade
4481 attacks'' whereby the Git repository of a channel would be reset to an
4482 earlier or unrelated revision of itself, potentially leading you to
4483 install older, known-vulnerable versions of software packages.
4486 Make sure you understand its security implications before using
4487 @option{--allow-downgrades}.
4490 @item --disable-authentication
4491 Allow pulling channel code without authenticating it.
4493 @cindex authentication, of channel code
4494 By default, @command{guix pull} authenticates code downloaded from
4495 channels by verifying that its commits are signed by authorized
4496 developers, and raises an error if this is not the case. This option
4497 instructs it to not perform any such verification.
4500 Make sure you understand its security implications before using
4501 @option{--disable-authentication}.
4504 @item --system=@var{system}
4505 @itemx -s @var{system}
4506 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4507 the system type of the build host.
4510 Use the bootstrap Guile to build the latest Guix. This option is only
4511 useful to Guix developers.
4514 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
4515 repository and branch to pull from, as well as @emph{additional} repositories
4516 containing package modules that should be deployed. @xref{Channels}, for more
4519 In addition, @command{guix pull} supports all the common build options
4520 (@pxref{Common Build Options}).
4522 @node Invoking guix time-machine
4523 @section Invoking @command{guix time-machine}
4525 @cindex @command{guix time-machine}
4526 @cindex pinning, channels
4527 @cindex replicating Guix
4528 @cindex reproducibility, of Guix
4530 The @command{guix time-machine} command provides access to other
4531 revisions of Guix, for example to install older versions of packages,
4532 or to reproduce a computation in an identical environment. The revision
4533 of Guix to be used is defined by a commit or by a channel
4534 description file created by @command{guix describe}
4535 (@pxref{Invoking guix describe}).
4537 The general syntax is:
4540 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4543 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4544 @command{guix} command of the specified revision. The @var{options} that define
4545 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4548 @item --url=@var{url}
4549 @itemx --commit=@var{commit}
4550 @itemx --branch=@var{branch}
4551 Use the @code{guix} channel from the specified @var{url}, at the
4552 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4553 string), or @var{branch}.
4555 @item --channels=@var{file}
4556 @itemx -C @var{file}
4557 Read the list of channels from @var{file}. @var{file} must contain
4558 Scheme code that evaluates to a list of channel objects.
4559 @xref{Channels} for more information.
4562 As for @command{guix pull}, the absence of any options means that the
4563 latest commit on the master branch will be used. The command
4566 guix time-machine -- build hello
4569 will thus build the package @code{hello} as defined in the master branch,
4570 which is in general a newer revision of Guix than you have installed.
4571 Time travel works in both directions!
4573 Note that @command{guix time-machine} can trigger builds of channels and
4574 their dependencies, and these are controlled by the standard build
4575 options (@pxref{Common Build Options}).
4580 @c TODO: Remove this once we're more confident about API stability.
4582 The functionality described here is a ``technology preview'' as of version
4583 @value{VERSION}. As such, the interface is subject to change.
4587 @cindex composition of Guix revisions
4588 Sometimes you might need to mix packages from the revision of Guix you're
4589 currently running with packages available in a different revision of Guix.
4590 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4591 revisions in arbitrary ways.
4593 @cindex inferior packages
4594 Technically, an ``inferior'' is essentially a separate Guix process connected
4595 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4596 @code{(guix inferior)} module allows you to create inferiors and to
4597 communicate with them. It also provides a high-level interface to browse and
4598 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4600 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4601 to interact with a separate revision of Guix. For example, let's assume you
4602 want to install in your profile the current @code{guile} package, along with
4603 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4604 because the newer @code{guile-json} has an incompatible API and you want to
4605 run your code against the old API@. To do that, you could write a manifest for
4606 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4607 manifest, you would create an inferior for that old Guix revision you care
4608 about, and you would look up the @code{guile-json} package in the inferior:
4611 (use-modules (guix inferior) (guix channels)
4612 (srfi srfi-1)) ;for 'first'
4615 ;; This is the old revision from which we want to
4616 ;; extract guile-json.
4619 (url "https://git.savannah.gnu.org/git/guix.git")
4621 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4624 ;; An inferior representing the above revision.
4625 (inferior-for-channels channels))
4627 ;; Now create a manifest with the current "guile" package
4628 ;; and the old "guile-json" package.
4630 (list (first (lookup-inferior-packages inferior "guile-json"))
4631 (specification->package "guile")))
4634 On its first run, @command{guix package --manifest} might have to build the
4635 channel you specified before it can create the inferior; subsequent runs will
4636 be much faster because the Guix revision will be cached.
4638 The @code{(guix inferior)} module provides the following procedures to open an
4641 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4642 [#:cache-directory] [#:ttl]
4643 Return an inferior for @var{channels}, a list of channels. Use the cache at
4644 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4645 This procedure opens a new connection to the build daemon.
4647 As a side effect, this procedure may build or substitute binaries for
4648 @var{channels}, which can take time.
4651 @deffn {Scheme Procedure} open-inferior @var{directory} @
4652 [#:command "bin/guix"]
4653 Open the inferior Guix in @var{directory}, running
4654 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4655 the inferior could not be launched.
4658 @cindex inferior packages
4659 The procedures listed below allow you to obtain and manipulate inferior
4662 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4663 Return the list of packages known to @var{inferior}.
4666 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4668 Return the sorted list of inferior packages matching @var{name} in
4669 @var{inferior}, with highest version numbers first. If @var{version} is true,
4670 return only packages with a version number prefixed by @var{version}.
4673 @deffn {Scheme Procedure} inferior-package? @var{obj}
4674 Return true if @var{obj} is an inferior package.
4677 @deffn {Scheme Procedure} inferior-package-name @var{package}
4678 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4679 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4680 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4681 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4682 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4683 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4684 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4685 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4686 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4687 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4688 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4689 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4690 These procedures are the counterpart of package record accessors
4691 (@pxref{package Reference}). Most of them work by querying the inferior
4692 @var{package} comes from, so the inferior must still be live when you call
4696 Inferior packages can be used transparently like any other package or
4697 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4698 transparently handled by the @code{packages->manifest} procedure, which is
4699 commonly used in manifests (@pxref{Invoking guix package, the
4700 @option{--manifest} option of @command{guix package}}). Thus you can insert
4701 an inferior package pretty much anywhere you would insert a regular package:
4702 in manifests, in the @code{packages} field of your @code{operating-system}
4703 declaration, and so on.
4705 @node Invoking guix describe
4706 @section Invoking @command{guix describe}
4708 @cindex reproducibility
4709 @cindex replicating Guix
4710 Often you may want to answer questions like: ``Which revision of Guix am I
4711 using?'' or ``Which channels am I using?'' This is useful information in many
4712 situations: if you want to @emph{replicate} an environment on a different
4713 machine or user account, if you want to report a bug or to determine what
4714 change in the channels you are using caused it, or if you want to record your
4715 system state for reproducibility purposes. The @command{guix describe}
4716 command answers these questions.
4718 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4719 displays the channel(s) that it was built from, including their repository URL
4720 and commit IDs (@pxref{Channels}):
4724 Generation 10 Sep 03 2018 17:32:44 (current)
4726 repository URL: https://git.savannah.gnu.org/git/guix.git
4728 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4731 If you're familiar with the Git version control system, this is similar in
4732 spirit to @command{git describe}; the output is also similar to that of
4733 @command{guix pull --list-generations}, but limited to the current generation
4734 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4735 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4736 information is all it takes to describe the revision of Guix you're using, and
4737 also to replicate it.
4739 To make it easier to replicate Guix, @command{guix describe} can also be asked
4740 to return a list of channels instead of the human-readable description above:
4743 $ guix describe -f channels
4746 (url "https://git.savannah.gnu.org/git/guix.git")
4748 "e0fa68c7718fffd33d81af415279d6ddb518f727")
4750 (make-channel-introduction
4751 "9edb3f66fd807b096b48283debdcddccfea34bad"
4752 (openpgp-fingerprint
4753 "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
4757 You can save this to a file and feed it to @command{guix pull -C} on some
4758 other machine or at a later point in time, which will instantiate @emph{this
4759 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4760 From there on, since you're able to deploy the same revision of Guix, you can
4761 just as well @emph{replicate a complete software environment}. We humbly
4762 think that this is @emph{awesome}, and we hope you'll like it too!
4764 The details of the options supported by @command{guix describe} are as
4768 @item --format=@var{format}
4769 @itemx -f @var{format}
4770 Produce output in the specified @var{format}, one of:
4774 produce human-readable output;
4776 produce a list of channel specifications that can be passed to @command{guix
4777 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4779 @item channels-sans-intro
4780 like @code{channels}, but omit the @code{introduction} field; use it to
4781 produce a channel specification suitable for Guix version 1.1.0 or
4782 earlier---the @code{introduction} field has to do with channel
4783 authentication (@pxref{Channels, Channel Authentication}) and is not
4784 supported by these older versions;
4787 produce a list of channel specifications in JSON format;
4789 produce a list of channel specifications in Recutils format.
4792 @item --list-formats
4793 Display available formats for @option{--format} option.
4795 @item --profile=@var{profile}
4796 @itemx -p @var{profile}
4797 Display information about @var{profile}.
4800 @node Invoking guix archive
4801 @section Invoking @command{guix archive}
4803 @cindex @command{guix archive}
4805 The @command{guix archive} command allows users to @dfn{export} files
4806 from the store into a single archive, and to later @dfn{import} them on
4807 a machine that runs Guix.
4808 In particular, it allows store files to be transferred from one machine
4809 to the store on another machine.
4812 If you're looking for a way to produce archives in a format suitable for
4813 tools other than Guix, @pxref{Invoking guix pack}.
4816 @cindex exporting store items
4817 To export store files as an archive to standard output, run:
4820 guix archive --export @var{options} @var{specifications}...
4823 @var{specifications} may be either store file names or package
4824 specifications, as for @command{guix package} (@pxref{Invoking guix
4825 package}). For instance, the following command creates an archive
4826 containing the @code{gui} output of the @code{git} package and the main
4827 output of @code{emacs}:
4830 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4833 If the specified packages are not built yet, @command{guix archive}
4834 automatically builds them. The build process may be controlled with the
4835 common build options (@pxref{Common Build Options}).
4837 To transfer the @code{emacs} package to a machine connected over SSH,
4841 guix archive --export -r emacs | ssh the-machine guix archive --import
4845 Similarly, a complete user profile may be transferred from one machine
4846 to another like this:
4849 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4850 ssh the-machine guix archive --import
4854 However, note that, in both examples, all of @code{emacs} and the
4855 profile as well as all of their dependencies are transferred (due to
4856 @option{-r}), regardless of what is already available in the store on
4857 the target machine. The @option{--missing} option can help figure out
4858 which items are missing from the target store. The @command{guix copy}
4859 command simplifies and optimizes this whole process, so this is probably
4860 what you should use in this case (@pxref{Invoking guix copy}).
4862 @cindex nar, archive format
4863 @cindex normalized archive (nar)
4864 @cindex nar bundle, archive format
4865 Each store item is written in the @dfn{normalized archive} or @dfn{nar}
4866 format (described below), and the output of @command{guix archive
4867 --export} (and input of @command{guix archive --import}) is a @dfn{nar
4871 comparable in spirit to `tar', but with differences
4872 that make it more appropriate for our purposes. First, rather than
4873 recording all Unix metadata for each file, the nar format only mentions
4874 the file type (regular, directory, or symbolic link); Unix permissions
4875 and owner/group are dismissed. Second, the order in which directory
4876 entries are stored always follows the order of file names according to
4877 the C locale collation order. This makes archive production fully
4880 That nar bundle format is essentially the concatenation of zero or more
4881 nars along with metadata for each store item it contains: its file name,
4882 references, corresponding derivation, and a digital signature.
4884 When exporting, the daemon digitally signs the contents of the archive,
4885 and that digital signature is appended. When importing, the daemon
4886 verifies the signature and rejects the import in case of an invalid
4887 signature or if the signing key is not authorized.
4888 @c FIXME: Add xref to daemon doc about signatures.
4890 The main options are:
4894 Export the specified store files or packages (see below). Write the
4895 resulting archive to the standard output.
4897 Dependencies are @emph{not} included in the output, unless
4898 @option{--recursive} is passed.
4902 When combined with @option{--export}, this instructs @command{guix archive}
4903 to include dependencies of the given items in the archive. Thus, the
4904 resulting archive is self-contained: it contains the closure of the
4905 exported store items.
4908 Read an archive from the standard input, and import the files listed
4909 therein into the store. Abort if the archive has an invalid digital
4910 signature, or if it is signed by a public key not among the authorized
4911 keys (see @option{--authorize} below).
4914 Read a list of store file names from the standard input, one per line,
4915 and write on the standard output the subset of these files missing from
4918 @item --generate-key[=@var{parameters}]
4919 @cindex signing, archives
4920 Generate a new key pair for the daemon. This is a prerequisite before
4921 archives can be exported with @option{--export}. This
4922 operation is usually instantaneous but it can take time if the system's
4923 entropy pool needs to be refilled. On Guix System,
4924 @code{guix-service-type} takes care of generating this key pair the
4927 The generated key pair is typically stored under @file{/etc/guix}, in
4928 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4929 key, which must be kept secret). When @var{parameters} is omitted,
4930 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4931 versions before 1.6.0, it is a 4096-bit RSA key.
4932 Alternatively, @var{parameters} can specify
4933 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4934 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4935 Libgcrypt Reference Manual}).
4938 @cindex authorizing, archives
4939 Authorize imports signed by the public key passed on standard input.
4940 The public key must be in ``s-expression advanced format''---i.e., the
4941 same format as the @file{signing-key.pub} file.
4943 The list of authorized keys is kept in the human-editable file
4944 @file{/etc/guix/acl}. The file contains
4945 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4946 s-expressions''} and is structured as an access-control list in the
4947 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4950 @item --extract=@var{directory}
4951 @itemx -x @var{directory}
4952 Read a single-item archive as served by substitute servers
4953 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4954 low-level operation needed in only very narrow use cases; see below.
4956 For example, the following command extracts the substitute for Emacs
4957 served by @code{@value{SUBSTITUTE-SERVER-1}} to @file{/tmp/emacs}:
4961 https://@value{SUBSTITUTE-SERVER-1}/nar/gzip/@dots{}-emacs-24.5 \
4962 | gunzip | guix archive -x /tmp/emacs
4965 Single-item archives are different from multiple-item archives produced
4966 by @command{guix archive --export}; they contain a single store item,
4967 and they do @emph{not} embed a signature. Thus this operation does
4968 @emph{no} signature verification and its output should be considered
4971 The primary purpose of this operation is to facilitate inspection of
4972 archive contents coming from possibly untrusted substitute servers
4973 (@pxref{Invoking guix challenge}).
4977 Read a single-item archive as served by substitute servers
4978 (@pxref{Substitutes}) and print the list of files it contains, as in
4983 https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-emacs-26.3 \
4984 | lzip -d | guix archive -t
4989 @c *********************************************************************
4994 @cindex @file{channels.scm}, configuration file
4995 @cindex configuration file for channels
4996 @cindex @command{guix pull}, configuration file
4997 @cindex configuration of @command{guix pull}
4998 Guix and its package collection are updated by running @command{guix pull}
4999 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
5000 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
5001 customized by defining @dfn{channels} in the
5002 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
5003 of a Git repository to be deployed, and @command{guix pull} can be instructed
5004 to pull from one or more channels. In other words, channels can be used
5005 to @emph{customize} and to @emph{extend} Guix, as we will see below.
5006 Guix is able to take into account security concerns and deal with authenticated
5010 * Specifying Additional Channels:: Extending the package collection.
5011 * Using a Custom Guix Channel:: Using a customized Guix.
5012 * Replicating Guix:: Running the @emph{exact same} Guix.
5013 * Channel Authentication:: How Guix verifies what it fetches.
5014 * Channels with Substitutes:: Using channels with available substitutes.
5015 * Creating a Channel:: How to write your custom channel.
5016 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
5017 * Declaring Channel Dependencies:: How to depend on other channels.
5018 * Specifying Channel Authorizations:: Defining channel authors authorizations.
5019 * Primary URL:: Distinguishing mirror to original.
5020 * Writing Channel News:: Communicating information to channel's users.
5023 @node Specifying Additional Channels
5024 @section Specifying Additional Channels
5026 @cindex extending the package collection (channels)
5027 @cindex variant packages (channels)
5028 You can specify @emph{additional channels} to pull from. To use a channel, write
5029 @code{~/.config/guix/channels.scm} to instruct @command{guix pull} to pull from it
5030 @emph{in addition} to the default Guix channel(s):
5032 @vindex %default-channels
5034 ;; Add variant packages to those Guix provides.
5036 (name 'variant-packages)
5037 (url "https://example.org/variant-packages.git"))
5042 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
5043 add a channel the list of channels that the variable @code{%default-channels}
5044 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
5045 Manual}). With this file in place, @command{guix pull} builds not only Guix
5046 but also the package modules from your own repository. The result in
5047 @file{~/.config/guix/current} is the union of Guix with your own package
5051 $ guix pull --list-generations
5053 Generation 19 Aug 27 2018 16:20:48
5055 repository URL: https://git.savannah.gnu.org/git/guix.git
5057 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
5058 variant-packages dd3df5e
5059 repository URL: https://example.org/variant-packages.git
5061 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
5062 11 new packages: variant-gimp, variant-emacs-with-cool-features, @dots{}
5063 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
5067 The output of @command{guix pull} above shows that Generation@tie{}19 includes
5068 both Guix and packages from the @code{variant-personal-packages} channel. Among
5069 the new and upgraded packages that are listed, some like @code{variant-gimp} and
5070 @code{variant-emacs-with-cool-features} might come from
5071 @code{variant-packages}, while others come from the Guix default channel.
5073 @node Using a Custom Guix Channel
5074 @section Using a Custom Guix Channel
5076 The channel called @code{guix} specifies where Guix itself---its command-line
5077 tools as well as its package collection---should be downloaded. For instance,
5078 suppose you want to update from another copy of the Guix repository at
5079 @code{example.org}, and specifically the @code{super-hacks} branch, you can
5080 write in @code{~/.config/guix/channels.scm} this specification:
5083 ;; Tell 'guix pull' to use another repo.
5086 (url "https://example.org/another-guix.git")
5087 (branch "super-hacks")))
5091 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
5092 branch of the repository at @code{example.org}. The authentication concern is
5093 addressed below ((@pxref{Channel Authentication}).
5095 @node Replicating Guix
5096 @section Replicating Guix
5098 @cindex pinning, channels
5099 @cindex replicating Guix
5100 @cindex reproducibility, of Guix
5101 The @command{guix pull --list-generations} output above shows precisely which
5102 commits were used to build this instance of Guix. We can thus replicate it,
5103 say, on another machine, by providing a channel specification in
5104 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
5107 ;; Deploy specific commits of my channels of interest.
5110 (url "https://git.savannah.gnu.org/git/guix.git")
5111 (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
5113 (name 'variant-packages)
5114 (url "https://example.org/variant-packages.git")
5115 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
5118 The @command{guix describe --format=channels} command can even generate this
5119 list of channels directly (@pxref{Invoking guix describe}). The resulting
5120 file can be used with the -C options of @command{guix pull}
5121 (@pxref{Invoking guix pull}) or @command{guix time-machine}
5122 (@pxref{Invoking guix time-machine}).
5124 At this point the two machines run the @emph{exact same Guix}, with access to
5125 the @emph{exact same packages}. The output of @command{guix build gimp} on
5126 one machine will be exactly the same, bit for bit, as the output of the same
5127 command on the other machine. It also means both machines have access to all
5128 the source code of Guix and, transitively, to all the source code of every
5131 This gives you super powers, allowing you to track the provenance of binary
5132 artifacts with very fine grain, and to reproduce software environments at
5133 will---some sort of ``meta reproducibility'' capabilities, if you will.
5134 @xref{Inferiors}, for another way to take advantage of these super powers.
5136 @node Channel Authentication
5137 @section Channel Authentication
5139 @anchor{channel-authentication}
5140 @cindex authentication, of channel code
5141 The @command{guix pull} and @command{guix time-machine} commands
5142 @dfn{authenticate} the code retrieved from channels: they make sure each
5143 commit that is fetched is signed by an authorized developer. The goal
5144 is to protect from unauthorized modifications to the channel that would
5145 lead users to run malicious code.
5147 As a user, you must provide a @dfn{channel introduction} in your
5148 channels file so that Guix knows how to authenticate its first commit.
5149 A channel specification, including its introduction, looks something
5154 (name 'some-channel)
5155 (url "https://example.org/some-channel.git")
5157 (make-channel-introduction
5158 "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
5159 (openpgp-fingerprint
5160 "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5163 The specification above shows the name and URL of the channel. The call
5164 to @code{make-channel-introduction} above specifies that authentication
5165 of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
5166 by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
5168 For the main channel, called @code{guix}, you automatically get that
5169 information from your Guix installation. For other channels, include
5170 the channel introduction provided by the channel authors in your
5171 @file{channels.scm} file. Make sure you retrieve the channel
5172 introduction from a trusted source since that is the root of your trust.
5174 If you're curious about the authentication mechanics, read on!
5176 @node Channels with Substitutes
5177 @section Channels with Substitutes
5179 When running @command{guix pull}, Guix will first compile the
5180 definitions of every available package. This is an expensive operation
5181 for which substitutes (@pxref{Substitutes}) may be available. The
5182 following snippet in @file{channels.scm} will ensure that @command{guix
5183 pull} uses the latest commit with available substitutes for the package
5184 definitions: this is done by querying the continuous integration
5185 server at @url{https://ci.guix.gnu.org}.
5188 (use-modules (guix ci))
5190 (list (channel-with-substitutes-available
5191 %default-guix-channel
5192 "https://ci.guix.gnu.org"))
5195 Note that this does not mean that all the packages that you will
5196 install after running @command{guix pull} will have available
5197 substitutes. It only ensures that @command{guix pull} will not try to
5198 compile package definitions. This is particularly useful when using
5199 machines with limited resources.
5201 @node Creating a Channel
5202 @section Creating a Channel
5204 @cindex personal packages (channels)
5205 @cindex channels, for personal packages
5206 Let's say you have a bunch of custom package variants or personal packages
5207 that you think would make little sense to contribute to the Guix project, but
5208 would like to have these packages transparently available to you at the
5209 command line. You would first write modules containing those package
5210 definitions (@pxref{Package Modules}), maintain them in a Git repository, and
5211 then you and anyone else can use it as an additional channel to get packages
5214 @c What follows stems from discussions at
5215 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
5216 @c earlier discussions on guix-devel@gnu.org.
5218 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
5219 publish your personal channel to the world, we would like to share a few words
5224 Before publishing a channel, please consider contributing your package
5225 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
5226 to free software of all sorts, and packages in Guix proper are readily
5227 available to all Guix users and benefit from the project's quality assurance
5231 When you maintain package definitions outside Guix, we, Guix developers,
5232 consider that @emph{the compatibility burden is on you}. Remember that
5233 package modules and package definitions are just Scheme code that uses various
5234 programming interfaces (APIs). We want to remain free to change these APIs to
5235 keep improving Guix, possibly in ways that break your channel. We never
5236 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
5240 Corollary: if you're using an external channel and that channel breaks, please
5241 @emph{report the issue to the channel authors}, not to the Guix project.
5244 You've been warned! Having said this, we believe external channels are a
5245 practical way to exert your freedom to augment Guix' package collection and to
5246 share your improvements, which are basic tenets of
5247 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
5248 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
5251 To create a channel, create a Git repository containing your own package
5252 modules and make it available. The repository can contain anything, but a
5253 useful channel will contain Guile modules that export packages. Once you
5254 start using a channel, Guix will behave as if the root directory of that
5255 channel's Git repository has been added to the Guile load path (@pxref{Load
5256 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
5257 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
5258 module, then the module will be available under the name @code{(my-packages
5259 my-tools)}, and you will be able to use it like any other module
5260 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
5262 As a channel author, consider bundling authentication material with your
5263 channel so that users can authenticate it. @xref{Channel
5264 Authentication}, and @ref{Specifying Channel Authorizations}, for info
5268 @node Package Modules in a Sub-directory
5269 @section Package Modules in a Sub-directory
5271 @cindex subdirectory, channels
5272 As a channel author, you may want to keep your channel modules in a
5273 sub-directory. If your modules are in the sub-directory @file{guix}, you must
5274 add a meta-data file @file{.guix-channel} that contains:
5282 @node Declaring Channel Dependencies
5283 @section Declaring Channel Dependencies
5285 @cindex dependencies, channels
5286 @cindex meta-data, channels
5287 Channel authors may decide to augment a package collection provided by other
5288 channels. They can declare their channel to be dependent on other channels in
5289 a meta-data file @file{.guix-channel}, which is to be placed in the root of
5290 the channel repository.
5292 The meta-data file should contain a simple S-expression like this:
5299 (name some-collection)
5300 (url "https://example.org/first-collection.git")
5302 ;; The 'introduction' bit below is optional: you would
5303 ;; provide it for dependencies that can be authenticated.
5305 (channel-introduction
5307 (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
5308 (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5310 (name some-other-collection)
5311 (url "https://example.org/second-collection.git")
5312 (branch "testing"))))
5315 In the above example this channel is declared to depend on two other channels,
5316 which will both be fetched automatically. The modules provided by the channel
5317 will be compiled in an environment where the modules of all these declared
5318 channels are available.
5320 For the sake of reliability and maintainability, you should avoid dependencies
5321 on channels that you don't control, and you should aim to keep the number of
5322 dependencies to a minimum.
5324 @node Specifying Channel Authorizations
5325 @section Specifying Channel Authorizations
5327 @cindex channel authorizations
5328 @anchor{channel-authorizations}
5329 As we saw above, Guix ensures the source code it pulls from channels
5330 comes from authorized developers. As a channel author, you need to
5331 specify the list of authorized developers in the
5332 @file{.guix-authorizations} file in the channel's Git repository. The
5333 authentication rule is simple: each commit must be signed by a key
5334 listed in the @file{.guix-authorizations} file of its parent
5335 commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
5336 (DAG). Each commit can have zero or more parents; ``regular'' commits
5337 have one parent and merge commits have two parent commits. Read
5338 @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
5339 for Computer Scientists}} for a great overview.} The
5340 @file{.guix-authorizations} file looks like this:
5343 ;; Example '.guix-authorizations' file.
5346 (version 0) ;current file format version
5348 (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
5350 ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
5352 ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
5356 Each fingerprint is followed by optional key/value pairs, as in the
5357 example above. Currently these key/value pairs are ignored.
5359 This authentication rule creates a chicken-and-egg issue: how do we
5360 authenticate the first commit? Related to that: how do we deal with
5361 channels whose repository history contains unsigned commits and lack
5362 @file{.guix-authorizations}? And how do we fork existing channels?
5364 @cindex channel introduction
5365 Channel introductions answer these questions by describing the first
5366 commit of a channel that should be authenticated. The first time a
5367 channel is fetched with @command{guix pull} or @command{guix
5368 time-machine}, the command looks up the introductory commit and verifies
5369 that it is signed by the specified OpenPGP key. From then on, it
5370 authenticates commits according to the rule above.
5372 Additionally, your channel must provide all the OpenPGP keys that were
5373 ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
5374 files, which can be either binary or ``ASCII-armored''. By default,
5375 those @file{.key} files are searched for in the branch named
5376 @code{keyring} but you can specify a different branch name in
5377 @code{.guix-channel} like so:
5382 (keyring-reference "my-keyring-branch"))
5385 To summarize, as the author of a channel, there are three things you have
5386 to do to allow users to authenticate your code:
5390 Export the OpenPGP keys of past and present committers with @command{gpg
5391 --export} and store them in @file{.key} files, by default in a branch
5392 named @code{keyring} (we recommend making it an @dfn{orphan branch}).
5395 Introduce an initial @file{.guix-authorizations} in the channel's
5396 repository. Do that in a signed commit (@pxref{Commit Access}, for
5397 information on how to sign Git commits.)
5400 Advertise the channel introduction, for instance on your channel's web
5401 page. The channel introduction, as we saw above, is the commit/key
5402 pair---i.e., the commit that introduced @file{.guix-authorizations}, and
5403 the fingerprint of the OpenPGP used to sign it.
5406 Before pushing to your public Git repository, you can run @command{guix
5407 git-authenticate} to verify that you did sign all the commits you are
5408 about to push with an authorized key:
5411 guix git authenticate @var{commit} @var{signer}
5415 where @var{commit} and @var{signer} are your channel introduction.
5416 @xref{Invoking guix git authenticate}, for details.
5418 Publishing a signed channel requires discipline: any mistake, such as an
5419 unsigned commit or a commit signed by an unauthorized key, will prevent
5420 users from pulling from your channel---well, that's the whole point of
5421 authentication! Pay attention to merges in particular: merge commits
5422 are considered authentic if and only if they are signed by a key present
5423 in the @file{.guix-authorizations} file of @emph{both} branches.
5426 @section Primary URL
5428 @cindex primary URL, channels
5429 Channel authors can indicate the primary URL of their channel's Git
5430 repository in the @file{.guix-channel} file, like so:
5435 (url "https://example.org/guix.git"))
5438 This allows @command{guix pull} to determine whether it is pulling code
5439 from a mirror of the channel; when that is the case, it warns the user
5440 that the mirror might be stale and displays the primary URL@. That way,
5441 users cannot be tricked into fetching code from a stale mirror that does
5442 not receive security updates.
5444 This feature only makes sense for authenticated repositories, such as
5445 the official @code{guix} channel, for which @command{guix pull} ensures
5446 the code it fetches is authentic.
5448 @node Writing Channel News
5449 @section Writing Channel News
5451 @cindex news, for channels
5452 Channel authors may occasionally want to communicate to their users
5453 information about important changes in the channel. You'd send them all
5454 an email, but that's not convenient.
5456 Instead, channels can provide a @dfn{news file}; when the channel users
5457 run @command{guix pull}, that news file is automatically read and
5458 @command{guix pull --news} can display the announcements that correspond
5459 to the new commits that have been pulled, if any.
5461 To do that, channel authors must first declare the name of the news file
5462 in their @file{.guix-channel} file:
5467 (news-file "etc/news.txt"))
5470 The news file itself, @file{etc/news.txt} in this example, must look
5471 something like this:
5476 (entry (tag "the-bug-fix")
5477 (title (en "Fixed terrible bug")
5479 (body (en "@@emph@{Good news@}! It's fixed!")
5480 (eo "Certe ĝi pli bone funkcias nun!")))
5481 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
5482 (title (en "Added a great package")
5483 (ca "Què vol dir guix?"))
5484 (body (en "Don't miss the @@code@{hello@} package!"))))
5487 While the news file is using the Scheme syntax, avoid naming it with a
5488 @file{.scm} extension or else it will get picked up when building the
5489 channel and yield an error since it is not a valid module.
5490 Alternatively, you can move the channel module to a subdirectory and
5491 store the news file in another directory.
5493 The file consists of a list of @dfn{news entries}. Each entry is
5494 associated with a commit or tag: it describes changes made in this
5495 commit, possibly in preceding commits as well. Users see entries only
5496 the first time they obtain the commit the entry refers to.
5498 The @code{title} field should be a one-line summary while @code{body}
5499 can be arbitrarily long, and both can contain Texinfo markup
5500 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
5501 a list of language tag/message tuples, which allows @command{guix pull}
5502 to display news in the language that corresponds to the user's locale.
5504 If you want to translate news using a gettext-based workflow, you can
5505 extract translatable strings with @command{xgettext} (@pxref{xgettext
5506 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
5507 you write news entries in English first, the command below creates a PO
5508 file containing the strings to translate:
5511 xgettext -o news.po -l scheme -ken etc/news.txt
5514 To sum up, yes, you could use your channel as a blog. But beware, this
5515 is @emph{not quite} what your users might expect.
5517 @c *********************************************************************
5519 @chapter Development
5521 @cindex software development
5522 If you are a software developer, Guix provides tools that you should find
5523 helpful---independently of the language you're developing in. This is what
5524 this chapter is about.
5526 The @command{guix environment} command provides a convenient way to set up
5527 @dfn{development environments} containing all the dependencies and tools
5528 necessary to work on the software package of your choice. The @command{guix
5529 pack} command allows you to create @dfn{application bundles} that can be
5530 easily distributed to users who do not run Guix.
5533 * Invoking guix environment:: Setting up development environments.
5534 * Invoking guix pack:: Creating software bundles.
5535 * The GCC toolchain:: Working with languages supported by GCC.
5536 * Invoking guix git authenticate:: Authenticating Git repositories.
5539 @node Invoking guix environment
5540 @section Invoking @command{guix environment}
5542 @cindex reproducible build environments
5543 @cindex development environments
5544 @cindex @command{guix environment}
5545 @cindex environment, package build environment
5546 The purpose of @command{guix environment} is to assist hackers in
5547 creating reproducible development environments without polluting their
5548 package profile. The @command{guix environment} tool takes one or more
5549 packages, builds all of their inputs, and creates a shell
5550 environment to use them.
5552 The general syntax is:
5555 guix environment @var{options} @var{package}@dots{}
5558 The following example spawns a new shell set up for the development of
5562 guix environment guile
5565 If the needed dependencies are not built yet, @command{guix environment}
5566 automatically builds them. The environment of the new shell is an
5567 augmented version of the environment that @command{guix environment} was
5568 run in. It contains the necessary search paths for building the given
5569 package added to the existing environment variables. To create
5570 a ``pure'' environment, in which the original environment variables have
5571 been unset, use the @option{--pure} option@footnote{Users sometimes
5572 wrongfully augment environment variables such as @env{PATH} in their
5573 @file{~/.bashrc} file. As a consequence, when @command{guix
5574 environment} launches it, Bash may read @file{~/.bashrc}, thereby
5575 introducing ``impurities'' in these environment variables. It is an
5576 error to define such environment variables in @file{.bashrc}; instead,
5577 they should be defined in @file{.bash_profile}, which is sourced only by
5578 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
5579 Manual}, for details on Bash start-up files.}.
5581 Exiting from a Guix environment is the same as exiting from the shell,
5582 and will place the user back in the old environment before @command{guix
5583 environment} was invoked. The next garbage collection (@pxref{Invoking
5584 guix gc}) will clean up packages that were installed from within the
5585 environment and are no longer used outside of it.
5587 @vindex GUIX_ENVIRONMENT
5588 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
5589 variable in the shell it spawns; its value is the file name of the
5590 profile of this environment. This allows users to, say, define a
5591 specific prompt for development environments in their @file{.bashrc}
5592 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
5595 if [ -n "$GUIX_ENVIRONMENT" ]
5597 export PS1="\u@@\h \w [dev]\$ "
5602 ...@: or to browse the profile:
5605 $ ls "$GUIX_ENVIRONMENT/bin"
5608 Additionally, more than one package may be specified, in which case the
5609 union of the inputs for the given packages are used. For example, the
5610 command below spawns a shell where all of the dependencies of both Guile
5611 and Emacs are available:
5614 guix environment guile emacs
5617 Sometimes an interactive shell session is not desired. An arbitrary
5618 command may be invoked by placing the @code{--} token to separate the
5619 command from the rest of the arguments:
5622 guix environment guile -- make -j4
5625 In other situations, it is more convenient to specify the list of
5626 packages needed in the environment. For example, the following command
5627 runs @command{python} from an environment containing Python@tie{}2.7 and
5631 guix environment --ad-hoc python2-numpy python-2.7 -- python
5634 Furthermore, one might want the dependencies of a package and also some
5635 additional packages that are not build-time or runtime dependencies, but
5636 are useful when developing nonetheless. Because of this, the
5637 @option{--ad-hoc} flag is positional. Packages appearing before
5638 @option{--ad-hoc} are interpreted as packages whose dependencies will be
5639 added to the environment. Packages appearing after are interpreted as
5640 packages that will be added to the environment directly. For example,
5641 the following command creates a Guix development environment that
5642 additionally includes Git and strace:
5645 guix environment --pure guix --ad-hoc git strace
5649 Sometimes it is desirable to isolate the environment as much as
5650 possible, for maximal purity and reproducibility. In particular, when
5651 using Guix on a host distro that is not Guix System, it is desirable to
5652 prevent access to @file{/usr/bin} and other system-wide resources from
5653 the development environment. For example, the following command spawns
5654 a Guile REPL in a ``container'' where only the store and the current
5655 working directory are mounted:
5658 guix environment --ad-hoc --container guile -- guile
5662 The @option{--container} option requires Linux-libre 3.19 or newer.
5665 @cindex certificates
5666 Another typical use case for containers is to run security-sensitive
5667 applications such as a web browser. To run Eolie, we must expose and
5668 share some files and directories; we include @code{nss-certs} and expose
5669 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
5670 @env{DISPLAY} environment variable since containerized graphical
5671 applications won't display without it.
5674 guix environment --preserve='^DISPLAY$' --container --network \
5675 --expose=/etc/machine-id \
5676 --expose=/etc/ssl/certs/ \
5677 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
5678 --ad-hoc eolie nss-certs dbus -- eolie
5681 The available options are summarized below.
5684 @item --root=@var{file}
5685 @itemx -r @var{file}
5686 @cindex persistent environment
5687 @cindex garbage collector root, for environments
5688 Make @var{file} a symlink to the profile for this environment, and
5689 register it as a garbage collector root.
5691 This is useful if you want to protect your environment from garbage
5692 collection, to make it ``persistent''.
5694 When this option is omitted, the environment is protected from garbage
5695 collection only for the duration of the @command{guix environment}
5696 session. This means that next time you recreate the same environment,
5697 you could have to rebuild or re-download packages. @xref{Invoking guix
5698 gc}, for more on GC roots.
5700 @item --expression=@var{expr}
5701 @itemx -e @var{expr}
5702 Create an environment for the package or list of packages that
5703 @var{expr} evaluates to.
5705 For example, running:
5708 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
5711 starts a shell with the environment for this specific variant of the
5717 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
5720 starts a shell with all the base system packages available.
5722 The above commands only use the default output of the given packages.
5723 To select other outputs, two element tuples can be specified:
5726 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
5729 @item --load=@var{file}
5730 @itemx -l @var{file}
5731 Create an environment for the package or list of packages that the code
5732 within @var{file} evaluates to.
5734 As an example, @var{file} might contain a definition like this
5735 (@pxref{Defining Packages}):
5738 @verbatiminclude environment-gdb.scm
5741 @item --manifest=@var{file}
5742 @itemx -m @var{file}
5743 Create an environment for the packages contained in the manifest object
5744 returned by the Scheme code in @var{file}. This option can be repeated
5745 several times, in which case the manifests are concatenated.
5747 This is similar to the same-named option in @command{guix package}
5748 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
5752 Include all specified packages in the resulting environment, as if an
5753 @i{ad hoc} package were defined with them as inputs. This option is
5754 useful for quickly creating an environment without having to write a
5755 package expression to contain the desired inputs.
5757 For instance, the command:
5760 guix environment --ad-hoc guile guile-sdl -- guile
5763 runs @command{guile} in an environment where Guile and Guile-SDL are
5766 Note that this example implicitly asks for the default output of
5767 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
5768 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
5769 of @code{glib} (@pxref{Packages with Multiple Outputs}).
5771 This option may be composed with the default behavior of @command{guix
5772 environment}. Packages appearing before @option{--ad-hoc} are
5773 interpreted as packages whose dependencies will be added to the
5774 environment, the default behavior. Packages appearing after are
5775 interpreted as packages that will be added to the environment directly.
5778 Unset existing environment variables when building the new environment, except
5779 those specified with @option{--preserve} (see below). This has the effect of
5780 creating an environment in which search paths only contain package inputs.
5782 @item --preserve=@var{regexp}
5783 @itemx -E @var{regexp}
5784 When used alongside @option{--pure}, preserve the environment variables
5785 matching @var{regexp}---in other words, put them on a ``white list'' of
5786 environment variables that must be preserved. This option can be repeated
5790 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
5794 This example runs @command{mpirun} in a context where the only environment
5795 variables defined are @env{PATH}, environment variables whose name starts
5796 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
5799 @item --search-paths
5800 Display the environment variable definitions that make up the
5803 @item --system=@var{system}
5804 @itemx -s @var{system}
5805 Attempt to build for @var{system}---e.g., @code{i686-linux}.
5810 Run @var{command} within an isolated container. The current working
5811 directory outside the container is mapped inside the container.
5812 Additionally, unless overridden with @option{--user}, a dummy home
5813 directory is created that matches the current user's home directory, and
5814 @file{/etc/passwd} is configured accordingly.
5816 The spawned process runs as the current user outside the container. Inside
5817 the container, it has the same UID and GID as the current user, unless
5818 @option{--user} is passed (see below).
5822 For containers, share the network namespace with the host system.
5823 Containers created without this flag only have access to the loopback
5826 @item --link-profile
5828 For containers, link the environment profile to @file{~/.guix-profile}
5829 within the container and set @code{GUIX_ENVIRONMENT} to that.
5830 This is equivalent to making @file{~/.guix-profile} a symlink to the
5831 actual profile within the container.
5832 Linking will fail and abort the environment if the directory already
5833 exists, which will certainly be the case if @command{guix environment}
5834 was invoked in the user's home directory.
5836 Certain packages are configured to look in @file{~/.guix-profile} for
5837 configuration files and data;@footnote{For example, the
5838 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
5839 for additional fonts.} @option{--link-profile} allows these programs to
5840 behave as expected within the environment.
5842 @item --user=@var{user}
5843 @itemx -u @var{user}
5844 For containers, use the username @var{user} in place of the current
5845 user. The generated @file{/etc/passwd} entry within the container will
5846 contain the name @var{user}, the home directory will be
5847 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
5848 the UID and GID inside the container are 1000. @var{user}
5849 need not exist on the system.
5851 Additionally, any shared or exposed path (see @option{--share} and
5852 @option{--expose} respectively) whose target is within the current user's
5853 home directory will be remapped relative to @file{/home/USER}; this
5854 includes the automatic mapping of the current working directory.
5857 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
5859 guix environment --container --user=foo \
5860 --expose=$HOME/test \
5861 --expose=/tmp/target=$HOME/target
5864 While this will limit the leaking of user identity through home paths
5865 and each of the user fields, this is only one useful component of a
5866 broader privacy/anonymity solution---not one in and of itself.
5869 For containers, the default behavior is to share the current working
5870 directory with the isolated container and immediately change to that
5871 directory within the container. If this is undesirable,
5872 @option{--no-cwd} will cause the current working directory to @emph{not}
5873 be automatically shared and will change to the user's home directory
5874 within the container instead. See also @option{--user}.
5876 @item --expose=@var{source}[=@var{target}]
5877 @itemx --share=@var{source}[=@var{target}]
5878 For containers, @option{--expose} (resp. @option{--share}) exposes the
5879 file system @var{source} from the host system as the read-only
5880 (resp. writable) file system @var{target} within the container. If
5881 @var{target} is not specified, @var{source} is used as the target mount
5882 point in the container.
5884 The example below spawns a Guile REPL in a container in which the user's
5885 home directory is accessible read-only via the @file{/exchange}
5889 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
5894 @command{guix environment}
5895 also supports all of the common build options that @command{guix
5896 build} supports (@pxref{Common Build Options}) as well as package
5897 transformation options (@pxref{Package Transformation Options}).
5899 @node Invoking guix pack
5900 @section Invoking @command{guix pack}
5902 Occasionally you want to pass software to people who are not (yet!)
5903 lucky enough to be using Guix. You'd tell them to run @command{guix
5904 package -i @var{something}}, but that's not possible in this case. This
5905 is where @command{guix pack} comes in.
5908 If you are looking for ways to exchange binaries among machines that
5909 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5910 publish}, and @ref{Invoking guix archive}.
5915 @cindex application bundle
5916 @cindex software bundle
5917 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5918 @dfn{software bundle}: it creates a tarball or some other archive
5919 containing the binaries of the software you're interested in, and all
5920 its dependencies. The resulting archive can be used on any machine that
5921 does not have Guix, and people can run the exact same binaries as those
5922 you have with Guix. The pack itself is created in a bit-reproducible
5923 fashion, so anyone can verify that it really contains the build results
5924 that you pretend to be shipping.
5926 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5927 their dependencies, you can run:
5930 $ guix pack guile emacs emacs-geiser
5932 /gnu/store/@dots{}-pack.tar.gz
5935 The result here is a tarball containing a @file{/gnu/store} directory
5936 with all the relevant packages. The resulting tarball contains a
5937 @dfn{profile} with the three packages of interest; the profile is the
5938 same as would be created by @command{guix package -i}. It is this
5939 mechanism that is used to create Guix's own standalone binary tarball
5940 (@pxref{Binary Installation}).
5942 Users of this pack would have to run
5943 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5944 find inconvenient. To work around it, you can create, say, a
5945 @file{/opt/gnu/bin} symlink to the profile:
5948 guix pack -S /opt/gnu/bin=bin guile emacs emacs-geiser
5952 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5954 @cindex relocatable binaries, with @command{guix pack}
5955 What if the recipient of your pack does not have root privileges on
5956 their machine, and thus cannot unpack it in the root file system? In
5957 that case, you will want to use the @option{--relocatable} option (see
5958 below). This option produces @dfn{relocatable binaries}, meaning they
5959 they can be placed anywhere in the file system hierarchy: in the example
5960 above, users can unpack your tarball in their home directory and
5961 directly run @file{./opt/gnu/bin/guile}.
5963 @cindex Docker, build an image with guix pack
5964 Alternatively, you can produce a pack in the Docker image format using
5965 the following command:
5968 guix pack -f docker -S /bin=bin guile guile-readline
5972 The result is a tarball that can be passed to the @command{docker load}
5973 command, followed by @code{docker run}:
5976 docker load < @var{file}
5977 docker run -ti guile-guile-readline /bin/guile
5981 where @var{file} is the image returned by @var{guix pack}, and
5982 @code{guile-guile-readline} is its ``image tag''. See the
5983 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5984 documentation} for more information.
5986 @cindex Singularity, build an image with guix pack
5987 @cindex SquashFS, build an image with guix pack
5988 Yet another option is to produce a SquashFS image with the following
5992 guix pack -f squashfs bash guile emacs emacs-geiser
5996 The result is a SquashFS file system image that can either be mounted or
5997 directly be used as a file system container image with the
5998 @uref{https://www.sylabs.io/docs/, Singularity container execution
5999 environment}, using commands like @command{singularity shell} or
6000 @command{singularity exec}.
6002 Several command-line options allow you to customize your pack:
6005 @item --format=@var{format}
6006 @itemx -f @var{format}
6007 Produce a pack in the given @var{format}.
6009 The available formats are:
6013 This is the default format. It produces a tarball containing all the
6014 specified binaries and symlinks.
6017 This produces a tarball that follows the
6018 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
6019 Docker Image Specification}. The ``repository name'' as it appears in
6020 the output of the @command{docker images} command is computed from
6021 package names passed on the command line or in the manifest file.
6024 This produces a SquashFS image containing all the specified binaries and
6025 symlinks, as well as empty mount points for virtual file systems like
6029 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
6030 For that reason, @command{guix pack -f squashfs} always implies @code{-S
6031 /bin=bin}. Thus, your @command{guix pack} invocation must always start
6032 with something like:
6035 guix pack -f squashfs bash @dots{}
6038 If you forget the @code{bash} (or similar) package, @command{singularity
6039 run} and @command{singularity exec} will fail with an unhelpful ``no
6040 such file or directory'' message.
6044 @cindex relocatable binaries
6047 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
6048 anywhere in the file system hierarchy and run from there.
6050 When this option is passed once, the resulting binaries require support for
6051 @dfn{user namespaces} in the kernel Linux; when passed
6052 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
6053 PRoot support, can be thought of as the abbreviation of ``Really
6054 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
6055 other techniques if user namespaces are unavailable, and essentially
6056 work anywhere---see below for the implications.
6058 For example, if you create a pack containing Bash with:
6061 guix pack -RR -S /mybin=bin bash
6065 ...@: you can copy that pack to a machine that lacks Guix, and from your
6066 home directory as a normal user, run:
6074 In that shell, if you type @code{ls /gnu/store}, you'll notice that
6075 @file{/gnu/store} shows up and contains all the dependencies of
6076 @code{bash}, even though the machine actually lacks @file{/gnu/store}
6077 altogether! That is probably the simplest way to deploy Guix-built
6078 software on a non-Guix machine.
6081 By default, relocatable binaries rely on the @dfn{user namespace} feature of
6082 the kernel Linux, which allows unprivileged users to mount or change root.
6083 Old versions of Linux did not support it, and some GNU/Linux distributions
6086 To produce relocatable binaries that work even in the absence of user
6087 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
6088 case, binaries will try user namespace support and fall back to another
6089 @dfn{execution engine} if user namespaces are not supported. The
6090 following execution engines are supported:
6094 Try user namespaces and fall back to PRoot if user namespaces are not
6095 supported (see below).
6098 Try user namespaces and fall back to Fakechroot if user namespaces are
6099 not supported (see below).
6102 Run the program through user namespaces and abort if they are not
6106 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
6107 provides the necessary
6108 support for file system virtualization. It achieves that by using the
6109 @code{ptrace} system call on the running program. This approach has the
6110 advantage to work without requiring special kernel support, but it incurs
6111 run-time overhead every time a system call is made.
6114 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
6115 Fakechroot} virtualizes file system accesses by intercepting calls to C
6116 library functions such as @code{open}, @code{stat}, @code{exec}, and so
6117 on. Unlike PRoot, it incurs very little overhead. However, it does not
6118 always work: for example, some file system accesses made from within the
6119 C library are not intercepted, and file system accesses made @i{via}
6120 direct syscalls are not intercepted either, leading to erratic behavior.
6123 @vindex GUIX_EXECUTION_ENGINE
6124 When running a wrapped program, you can explicitly request one of the
6125 execution engines listed above by setting the
6126 @env{GUIX_EXECUTION_ENGINE} environment variable accordingly.
6129 @cindex entry point, for Docker images
6130 @item --entry-point=@var{command}
6131 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
6132 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
6133 support it. @var{command} must be relative to the profile contained in the
6136 The entry point specifies the command that tools like @code{docker run} or
6137 @code{singularity run} automatically start by default. For example, you can
6141 guix pack -f docker --entry-point=bin/guile guile
6144 The resulting pack can easily be loaded and @code{docker run} with no extra
6145 arguments will spawn @code{bin/guile}:
6148 docker load -i pack.tar.gz
6149 docker run @var{image-id}
6152 @item --expression=@var{expr}
6153 @itemx -e @var{expr}
6154 Consider the package @var{expr} evaluates to.
6156 This has the same purpose as the same-named option in @command{guix
6157 build} (@pxref{Additional Build Options, @option{--expression} in
6158 @command{guix build}}).
6160 @item --manifest=@var{file}
6161 @itemx -m @var{file}
6162 Use the packages contained in the manifest object returned by the Scheme
6163 code in @var{file}. This option can be repeated several times, in which
6164 case the manifests are concatenated.
6166 This has a similar purpose as the same-named option in @command{guix
6167 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
6168 same manifest files. It allows you to define a collection of packages
6169 once and use it both for creating profiles and for creating archives
6170 for use on machines that do not have Guix installed. Note that you can
6171 specify @emph{either} a manifest file @emph{or} a list of packages,
6174 @item --system=@var{system}
6175 @itemx -s @var{system}
6176 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
6177 the system type of the build host.
6179 @item --target=@var{triplet}
6180 @cindex cross-compilation
6181 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
6182 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
6183 configuration triplets,, autoconf, Autoconf}).
6185 @item --compression=@var{tool}
6186 @itemx -C @var{tool}
6187 Compress the resulting tarball using @var{tool}---one of @code{gzip},
6188 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
6191 @item --symlink=@var{spec}
6192 @itemx -S @var{spec}
6193 Add the symlinks specified by @var{spec} to the pack. This option can
6194 appear several times.
6196 @var{spec} has the form @code{@var{source}=@var{target}}, where
6197 @var{source} is the symlink that will be created and @var{target} is the
6200 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
6201 symlink pointing to the @file{bin} sub-directory of the profile.
6203 @item --save-provenance
6204 Save provenance information for the packages passed on the command line.
6205 Provenance information includes the URL and commit of the channels in use
6208 Provenance information is saved in the
6209 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
6210 usual package metadata---the name and version of each package, their
6211 propagated inputs, and so on. It is useful information to the recipient of
6212 the pack, who then knows how the pack was (supposedly) obtained.
6214 This option is not enabled by default because, like timestamps, provenance
6215 information contributes nothing to the build process. In other words, there
6216 is an infinity of channel URLs and commit IDs that can lead to the same pack.
6217 Recording such ``silent'' metadata in the output thus potentially breaks the
6218 source-to-binary bitwise reproducibility property.
6220 @item --root=@var{file}
6221 @itemx -r @var{file}
6222 @cindex garbage collector root, for packs
6223 Make @var{file} a symlink to the resulting pack, and register it as a garbage
6226 @item --localstatedir
6227 @itemx --profile-name=@var{name}
6228 Include the ``local state directory'', @file{/var/guix}, in the resulting
6229 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
6230 profile---by default @var{name} is @code{guix-profile}, which corresponds to
6231 @file{~root/.guix-profile}.
6233 @file{/var/guix} contains the store database (@pxref{The Store}) as well
6234 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
6235 the pack means that the store is ``complete'' and manageable by Guix;
6236 not providing it pack means that the store is ``dead'': items cannot be
6237 added to it or removed from it after extraction of the pack.
6239 One use case for this is the Guix self-contained binary tarball
6240 (@pxref{Binary Installation}).
6244 Print the name of the derivation that builds the pack.
6247 Use the bootstrap binaries to build the pack. This option is only
6248 useful to Guix developers.
6251 In addition, @command{guix pack} supports all the common build options
6252 (@pxref{Common Build Options}) and all the package transformation
6253 options (@pxref{Package Transformation Options}).
6256 @node The GCC toolchain
6257 @section The GCC toolchain
6261 @cindex linker wrapper
6262 @cindex toolchain, for C development
6263 @cindex toolchain, for Fortran development
6265 If you need a complete toolchain for compiling and linking C or C++
6266 source code, use the @code{gcc-toolchain} package. This package
6267 provides a complete GCC toolchain for C/C++ development, including GCC
6268 itself, the GNU C Library (headers and binaries, plus debugging symbols
6269 in the @code{debug} output), Binutils, and a linker wrapper.
6271 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
6272 passed to the linker, add corresponding @code{-rpath} arguments, and
6273 invoke the actual linker with this new set of arguments. You can instruct the
6274 wrapper to refuse to link against libraries not in the store by setting the
6275 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
6277 The package @code{gfortran-toolchain} provides a complete GCC toolchain
6278 for Fortran development. For other languages, please use
6279 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
6282 @node Invoking guix git authenticate
6283 @section Invoking @command{guix git authenticate}
6285 The @command{guix git authenticate} command authenticates a Git checkout
6286 following the same rule as for channels (@pxref{channel-authentication,
6287 channel authentication}). That is, starting from a given commit, it
6288 ensures that all subsequent commits are signed by an OpenPGP key whose
6289 fingerprint appears in the @file{.guix-authorizations} file of its
6292 You will find this command useful if you maintain a channel. But in
6293 fact, this authentication mechanism is useful in a broader context, so
6294 you might want to use it for Git repositories that have nothing to do
6297 The general syntax is:
6300 guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
6303 By default, this command authenticates the Git checkout in the current
6304 directory; it outputs nothing and exits with exit code zero on success
6305 and non-zero on failure. @var{commit} above denotes the first commit
6306 where authentication takes place, and @var{signer} is the OpenPGP
6307 fingerprint of public key used to sign @var{commit}. Together, they
6308 form a ``channel introduction'' (@pxref{channel-authentication, channel
6309 introduction}). The options below allow you to fine-tune the process.
6312 @item --repository=@var{directory}
6313 @itemx -r @var{directory}
6314 Open the Git repository in @var{directory} instead of the current
6317 @item --keyring=@var{reference}
6318 @itemx -k @var{reference}
6319 Load OpenPGP keyring from @var{reference}, the reference of a branch
6320 such as @code{origin/keyring} or @code{my-keyring}. The branch must
6321 contain OpenPGP public keys in @file{.key} files, either in binary form
6322 or ``ASCII-armored''. By default the keyring is loaded from the branch
6323 named @code{keyring}.
6326 Display commit signing statistics upon completion.
6328 @item --cache-key=@var{key}
6329 Previously-authenticated commits are cached in a file under
6330 @file{~/.cache/guix/authentication}. This option forces the cache to be
6331 stored in file @var{key} in that directory.
6333 @item --historical-authorizations=@var{file}
6334 By default, any commit whose parent commit(s) lack the
6335 @file{.guix-authorizations} file is considered inauthentic. In
6336 contrast, this option considers the authorizations in @var{file} for any
6337 commit that lacks @file{.guix-authorizations}. The format of @var{file}
6338 is the same as that of @file{.guix-authorizations}
6339 (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
6343 @c *********************************************************************
6344 @node Programming Interface
6345 @chapter Programming Interface
6347 GNU Guix provides several Scheme programming interfaces (APIs) to
6348 define, build, and query packages. The first interface allows users to
6349 write high-level package definitions. These definitions refer to
6350 familiar packaging concepts, such as the name and version of a package,
6351 its build system, and its dependencies. These definitions can then be
6352 turned into concrete build actions.
6354 Build actions are performed by the Guix daemon, on behalf of users. In a
6355 standard setup, the daemon has write access to the store---the
6356 @file{/gnu/store} directory---whereas users do not. The recommended
6357 setup also has the daemon perform builds in chroots, under specific
6358 build users, to minimize interference with the rest of the system.
6361 Lower-level APIs are available to interact with the daemon and the
6362 store. To instruct the daemon to perform a build action, users actually
6363 provide it with a @dfn{derivation}. A derivation is a low-level
6364 representation of the build actions to be taken, and the environment in
6365 which they should occur---derivations are to package definitions what
6366 assembly is to C programs. The term ``derivation'' comes from the fact
6367 that build results @emph{derive} from them.
6369 This chapter describes all these APIs in turn, starting from high-level
6370 package definitions.
6373 * Package Modules:: Packages from the programmer's viewpoint.
6374 * Defining Packages:: Defining new packages.
6375 * Defining Package Variants:: Customizing packages.
6376 * Build Systems:: Specifying how packages are built.
6377 * Build Phases:: Phases of the build process of a package.
6378 * Build Utilities:: Helpers for your package definitions and more.
6379 * The Store:: Manipulating the package store.
6380 * Derivations:: Low-level interface to package derivations.
6381 * The Store Monad:: Purely functional interface to the store.
6382 * G-Expressions:: Manipulating build expressions.
6383 * Invoking guix repl:: Programming Guix in Guile
6386 @node Package Modules
6387 @section Package Modules
6389 From a programming viewpoint, the package definitions of the
6390 GNU distribution are provided by Guile modules in the @code{(gnu packages
6391 @dots{})} name space@footnote{Note that packages under the @code{(gnu
6392 packages @dots{})} module name space are not necessarily ``GNU
6393 packages''. This module naming scheme follows the usual Guile module
6394 naming convention: @code{gnu} means that these modules are distributed
6395 as part of the GNU system, and @code{packages} identifies modules that
6396 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
6397 Reference Manual}). For instance, the @code{(gnu packages emacs)}
6398 module exports a variable named @code{emacs}, which is bound to a
6399 @code{<package>} object (@pxref{Defining Packages}).
6401 The @code{(gnu packages @dots{})} module name space is
6402 automatically scanned for packages by the command-line tools. For
6403 instance, when running @code{guix install emacs}, all the @code{(gnu
6404 packages @dots{})} modules are scanned until one that exports a package
6405 object whose name is @code{emacs} is found. This package search
6406 facility is implemented in the @code{(gnu packages)} module.
6408 @cindex customization, of packages
6409 @cindex package module search path
6410 Users can store package definitions in modules with different
6411 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
6412 name and module name must match. For instance, the @code{(my-packages
6413 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
6414 relative to the load path specified with @option{--load-path} or
6415 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
6416 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
6417 these package definitions visible to the user interfaces:
6421 By adding the directory containing your package modules to the search path
6422 with the @code{-L} flag of @command{guix package} and other commands
6423 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
6424 environment variable described below.
6427 By defining a @dfn{channel} and configuring @command{guix pull} so that it
6428 pulls from it. A channel is essentially a Git repository containing package
6429 modules. @xref{Channels}, for more information on how to define and use
6433 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
6435 @defvr {Environment Variable} GUIX_PACKAGE_PATH
6436 This is a colon-separated list of directories to search for additional
6437 package modules. Directories listed in this variable take precedence
6438 over the own modules of the distribution.
6441 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
6442 each package is built based solely on other packages in the
6443 distribution. The root of this dependency graph is a small set of
6444 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
6445 bootstrap)} module. For more information on bootstrapping,
6446 @pxref{Bootstrapping}.
6448 @node Defining Packages
6449 @section Defining Packages
6451 The high-level interface to package definitions is implemented in the
6452 @code{(guix packages)} and @code{(guix build-system)} modules. As an
6453 example, the package definition, or @dfn{recipe}, for the GNU Hello
6454 package looks like this:
6457 (define-module (gnu packages hello)
6458 #:use-module (guix packages)
6459 #:use-module (guix download)
6460 #:use-module (guix build-system gnu)
6461 #:use-module (guix licenses)
6462 #:use-module (gnu packages gawk))
6464 (define-public hello
6470 (uri (string-append "mirror://gnu/hello/hello-" version
6474 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
6475 (build-system gnu-build-system)
6476 (arguments '(#:configure-flags '("--enable-silent-rules")))
6477 (inputs `(("gawk" ,gawk)))
6478 (synopsis "Hello, GNU world: An example GNU package")
6479 (description "Guess what GNU Hello prints!")
6480 (home-page "https://www.gnu.org/software/hello/")
6485 Without being a Scheme expert, the reader may have guessed the meaning
6486 of the various fields here. This expression binds the variable
6487 @code{hello} to a @code{<package>} object, which is essentially a record
6488 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
6489 This package object can be inspected using procedures found in the
6490 @code{(guix packages)} module; for instance, @code{(package-name hello)}
6491 returns---surprise!---@code{"hello"}.
6493 With luck, you may be able to import part or all of the definition of
6494 the package you are interested in from another repository, using the
6495 @code{guix import} command (@pxref{Invoking guix import}).
6497 In the example above, @code{hello} is defined in a module of its own,
6498 @code{(gnu packages hello)}. Technically, this is not strictly
6499 necessary, but it is convenient to do so: all the packages defined in
6500 modules under @code{(gnu packages @dots{})} are automatically known to
6501 the command-line tools (@pxref{Package Modules}).
6503 There are a few points worth noting in the above package definition:
6507 The @code{source} field of the package is an @code{<origin>} object
6508 (@pxref{origin Reference}, for the complete reference).
6509 Here, the @code{url-fetch} method from @code{(guix download)} is used,
6510 meaning that the source is a file to be downloaded over FTP or HTTP.
6512 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
6513 the GNU mirrors defined in @code{(guix download)}.
6515 The @code{sha256} field specifies the expected SHA256 hash of the file
6516 being downloaded. It is mandatory, and allows Guix to check the
6517 integrity of the file. The @code{(base32 @dots{})} form introduces the
6518 base32 representation of the hash. You can obtain this information with
6519 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
6520 hash} (@pxref{Invoking guix hash}).
6523 When needed, the @code{origin} form can also have a @code{patches} field
6524 listing patches to be applied, and a @code{snippet} field giving a
6525 Scheme expression to modify the source code.
6528 @cindex GNU Build System
6529 The @code{build-system} field specifies the procedure to build the
6530 package (@pxref{Build Systems}). Here, @code{gnu-build-system}
6531 represents the familiar GNU Build System, where packages may be
6532 configured, built, and installed with the usual @code{./configure &&
6533 make && make check && make install} command sequence.
6535 When you start packaging non-trivial software, you may need tools to
6536 manipulate those build phases, manipulate files, and so on. @xref{Build
6537 Utilities}, for more on this.
6540 The @code{arguments} field specifies options for the build system
6541 (@pxref{Build Systems}). Here it is interpreted by
6542 @code{gnu-build-system} as a request run @file{configure} with the
6543 @option{--enable-silent-rules} flag.
6549 What about these quote (@code{'}) characters? They are Scheme syntax to
6550 introduce a literal list; @code{'} is synonymous with @code{quote}.
6551 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
6552 for details. Here the value of the @code{arguments} field is a list of
6553 arguments passed to the build system down the road, as with @code{apply}
6554 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
6557 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
6558 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
6559 @code{#:configure-flags} is a keyword used to pass a keyword argument
6560 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
6564 The @code{inputs} field specifies inputs to the build process---i.e.,
6565 build-time or run-time dependencies of the package. Here, we define an
6566 input called @code{"gawk"} whose value is that of the @code{gawk}
6567 variable; @code{gawk} is itself bound to a @code{<package>} object.
6569 @cindex backquote (quasiquote)
6572 @cindex comma (unquote)
6576 @findex unquote-splicing
6577 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
6578 us to introduce a literal list in the @code{inputs} field, while
6579 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
6580 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
6583 Note that GCC, Coreutils, Bash, and other essential tools do not need to
6584 be specified as inputs here. Instead, @code{gnu-build-system} takes care
6585 of ensuring that they are present (@pxref{Build Systems}).
6587 However, any other dependencies need to be specified in the
6588 @code{inputs} field. Any dependency not specified here will simply be
6589 unavailable to the build process, possibly leading to a build failure.
6592 @xref{package Reference}, for a full description of possible fields.
6594 Once a package definition is in place, the
6595 package may actually be built using the @code{guix build} command-line
6596 tool (@pxref{Invoking guix build}), troubleshooting any build failures
6597 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
6598 package definition using the @command{guix edit} command
6599 (@pxref{Invoking guix edit}).
6600 @xref{Packaging Guidelines}, for
6601 more information on how to test package definitions, and
6602 @ref{Invoking guix lint}, for information on how to check a definition
6603 for style conformance.
6604 @vindex GUIX_PACKAGE_PATH
6605 Lastly, @pxref{Channels}, for information
6606 on how to extend the distribution by adding your own package definitions
6609 Finally, updating the package definition to a new upstream version
6610 can be partly automated by the @command{guix refresh} command
6611 (@pxref{Invoking guix refresh}).
6613 Behind the scenes, a derivation corresponding to the @code{<package>}
6614 object is first computed by the @code{package-derivation} procedure.
6615 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
6616 The build actions it prescribes may then be realized by using the
6617 @code{build-derivations} procedure (@pxref{The Store}).
6619 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
6620 Return the @code{<derivation>} object of @var{package} for @var{system}
6621 (@pxref{Derivations}).
6623 @var{package} must be a valid @code{<package>} object, and @var{system}
6624 must be a string denoting the target system type---e.g.,
6625 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
6626 must be a connection to the daemon, which operates on the store
6627 (@pxref{The Store}).
6631 @cindex cross-compilation
6632 Similarly, it is possible to compute a derivation that cross-builds a
6633 package for some other system:
6635 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
6636 @var{package} @var{target} [@var{system}]
6637 Return the @code{<derivation>} object of @var{package} cross-built from
6638 @var{system} to @var{target}.
6640 @var{target} must be a valid GNU triplet denoting the target hardware
6641 and operating system, such as @code{"aarch64-linux-gnu"}
6642 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
6645 Once you have package definitions, you can easily define @emph{variants}
6646 of those packages. @xref{Defining Package Variants}, for more on that.
6649 * package Reference:: The package data type.
6650 * origin Reference:: The origin data type.
6654 @node package Reference
6655 @subsection @code{package} Reference
6657 This section summarizes all the options available in @code{package}
6658 declarations (@pxref{Defining Packages}).
6660 @deftp {Data Type} package
6661 This is the data type representing a package recipe.
6665 The name of the package, as a string.
6667 @item @code{version}
6668 The version of the package, as a string. @xref{Version Numbers}, for
6672 An object telling how the source code for the package should be
6673 acquired. Most of the time, this is an @code{origin} object, which
6674 denotes a file fetched from the Internet (@pxref{origin Reference}). It
6675 can also be any other ``file-like'' object such as a @code{local-file},
6676 which denotes a file from the local file system (@pxref{G-Expressions,
6677 @code{local-file}}).
6679 @item @code{build-system}
6680 The build system that should be used to build the package (@pxref{Build
6683 @item @code{arguments} (default: @code{'()})
6684 The arguments that should be passed to the build system. This is a
6685 list, typically containing sequential keyword-value pairs.
6687 @item @code{inputs} (default: @code{'()})
6688 @itemx @code{native-inputs} (default: @code{'()})
6689 @itemx @code{propagated-inputs} (default: @code{'()})
6690 @cindex inputs, of packages
6691 These fields list dependencies of the package. Each one is a list of
6692 tuples, where each tuple has a label for the input (a string) as its
6693 first element, a package, origin, or derivation as its second element,
6694 and optionally the name of the output thereof that should be used, which
6695 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
6696 more on package outputs). For example, the list below specifies three
6700 `(("libffi" ,libffi)
6701 ("libunistring" ,libunistring)
6702 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
6705 @cindex cross compilation, package dependencies
6706 The distinction between @code{native-inputs} and @code{inputs} is
6707 necessary when considering cross-compilation. When cross-compiling,
6708 dependencies listed in @code{inputs} are built for the @emph{target}
6709 architecture; conversely, dependencies listed in @code{native-inputs}
6710 are built for the architecture of the @emph{build} machine.
6712 @code{native-inputs} is typically used to list tools needed at
6713 build time, but not at run time, such as Autoconf, Automake, pkg-config,
6714 Gettext, or Bison. @command{guix lint} can report likely mistakes in
6715 this area (@pxref{Invoking guix lint}).
6717 @anchor{package-propagated-inputs}
6718 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
6719 specified packages will be automatically installed to profiles
6720 (@pxref{Features, the role of profiles in Guix}) alongside the package
6721 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
6722 package}}, for information on how @command{guix package} deals with
6725 For example this is necessary when packaging a C/C++ library that needs
6726 headers of another library to compile, or when a pkg-config file refers
6727 to another one @i{via} its @code{Requires} field.
6729 Another example where @code{propagated-inputs} is useful is for languages
6730 that lack a facility to record the run-time search path akin to the
6731 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
6732 more. When packaging libraries written in those languages, ensure they
6733 can find library code they depend on at run time by listing run-time
6734 dependencies in @code{propagated-inputs} rather than @code{inputs}.
6736 @item @code{outputs} (default: @code{'("out")})
6737 The list of output names of the package. @xref{Packages with Multiple
6738 Outputs}, for typical uses of additional outputs.
6740 @item @code{native-search-paths} (default: @code{'()})
6741 @itemx @code{search-paths} (default: @code{'()})
6742 A list of @code{search-path-specification} objects describing
6743 search-path environment variables honored by the package.
6745 @item @code{replacement} (default: @code{#f})
6746 This must be either @code{#f} or a package object that will be used as a
6747 @dfn{replacement} for this package. @xref{Security Updates, grafts},
6750 @item @code{synopsis}
6751 A one-line description of the package.
6753 @item @code{description}
6754 A more elaborate description of the package.
6756 @item @code{license}
6757 @cindex license, of packages
6758 The license of the package; a value from @code{(guix licenses)},
6759 or a list of such values.
6761 @item @code{home-page}
6762 The URL to the home-page of the package, as a string.
6764 @item @code{supported-systems} (default: @code{%supported-systems})
6765 The list of systems supported by the package, as strings of the form
6766 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
6768 @item @code{location} (default: source location of the @code{package} form)
6769 The source location of the package. It is useful to override this when
6770 inheriting from another package, in which case this field is not
6771 automatically corrected.
6775 @deffn {Scheme Syntax} this-package
6776 When used in the @emph{lexical scope} of a package field definition, this
6777 identifier resolves to the package being defined.
6779 The example below shows how to add a package as a native input of itself when
6787 ;; When cross-compiled, Guile, for example, depends on
6788 ;; a native version of itself. Add it here.
6789 (native-inputs (if (%current-target-system)
6790 `(("self" ,this-package))
6794 It is an error to refer to @code{this-package} outside a package definition.
6797 Because packages are regular Scheme objects that capture a complete
6798 dependency graph and associated build procedures, it is often useful to
6799 write procedures that take a package and return a modified version
6800 thereof according to some parameters. Below are a few examples.
6802 @cindex tool chain, choosing a package's tool chain
6803 @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
6804 Return a variant of @var{package} that uses @var{toolchain} instead of
6805 the default GNU C/C++ toolchain. @var{toolchain} must be a list of
6806 inputs (label/package tuples) providing equivalent functionality, such
6807 as the @code{gcc-toolchain} package.
6809 The example below returns a variant of the @code{hello} package built
6810 with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
6811 GNU C Library) instead of the default tool chain:
6814 (let ((toolchain (specification->package "gcc-toolchain@@10")))
6815 (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
6818 The build tool chain is part of the @dfn{implicit inputs} of
6819 packages---it's usually not listed as part of the various ``inputs''
6820 fields and is instead pulled in by the build system. Consequently, this
6821 procedure works by changing the build system of @var{package} so that it
6822 pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
6823 for more on build systems.
6826 @node origin Reference
6827 @subsection @code{origin} Reference
6829 This section documents @dfn{origins}. An @code{origin} declaration
6830 specifies data that must be ``produced''---downloaded, usually---and
6831 whose content hash is known in advance. Origins are primarily used to
6832 represent the source code of packages (@pxref{Defining Packages}). For
6833 that reason, the @code{origin} form allows you to declare patches to
6834 apply to the original source code as well as code snippets to modify it.
6836 @deftp {Data Type} origin
6837 This is the data type representing a source code origin.
6841 An object containing the URI of the source. The object type depends on
6842 the @code{method} (see below). For example, when using the
6843 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
6844 values are: a URL represented as a string, or a list thereof.
6846 @cindex fixed-output derivations, for download
6848 A monadic procedure that handles the given URI@. The procedure must
6849 accept at least three arguments: the value of the @code{uri} field and
6850 the hash algorithm and hash value specified by the @code{hash} field.
6851 It must return a store item or a derivation in the store monad
6852 (@pxref{The Store Monad}); most methods return a fixed-output derivation
6853 (@pxref{Derivations}).
6855 Commonly used methods include @code{url-fetch}, which fetches data from
6856 a URL, and @code{git-fetch}, which fetches data from a Git repository
6860 A bytevector containing the SHA-256 hash of the source. This is
6861 equivalent to providing a @code{content-hash} SHA256 object in the
6862 @code{hash} field described below.
6865 The @code{content-hash} object of the source---see below for how to use
6866 @code{content-hash}.
6868 You can obtain this information using @code{guix download}
6869 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
6872 @item @code{file-name} (default: @code{#f})
6873 The file name under which the source code should be saved. When this is
6874 @code{#f}, a sensible default value will be used in most cases. In case
6875 the source is fetched from a URL, the file name from the URL will be
6876 used. For version control checkouts, it is recommended to provide the
6877 file name explicitly because the default is not very descriptive.
6879 @item @code{patches} (default: @code{'()})
6880 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
6881 file-like objects}) pointing to patches to be applied to the source.
6883 This list of patches must be unconditional. In particular, it cannot
6884 depend on the value of @code{%current-system} or
6885 @code{%current-target-system}.
6887 @item @code{snippet} (default: @code{#f})
6888 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
6889 in the source directory. This is a convenient way to modify the source,
6890 sometimes more convenient than a patch.
6892 @item @code{patch-flags} (default: @code{'("-p1")})
6893 A list of command-line flags that should be passed to the @code{patch}
6896 @item @code{patch-inputs} (default: @code{#f})
6897 Input packages or derivations to the patching process. When this is
6898 @code{#f}, the usual set of inputs necessary for patching are provided,
6899 such as GNU@tie{}Patch.
6901 @item @code{modules} (default: @code{'()})
6902 A list of Guile modules that should be loaded during the patching
6903 process and while running the code in the @code{snippet} field.
6905 @item @code{patch-guile} (default: @code{#f})
6906 The Guile package that should be used in the patching process. When
6907 this is @code{#f}, a sensible default is used.
6911 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
6912 Construct a content hash object for the given @var{algorithm}, and with
6913 @var{value} as its hash value. When @var{algorithm} is omitted, assume
6914 it is @code{sha256}.
6916 @var{value} can be a literal string, in which case it is base32-decoded,
6917 or it can be a bytevector.
6919 The following forms are all equivalent:
6922 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
6923 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
6925 (content-hash (base32
6926 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
6927 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
6931 Technically, @code{content-hash} is currently implemented as a macro.
6932 It performs sanity checks at macro-expansion time, when possible, such
6933 as ensuring that @var{value} has the right size for @var{algorithm}.
6936 As we have seen above, how exactly the data an origin refers to is
6937 retrieved is determined by its @code{method} field. The @code{(guix
6938 download)} module provides the most common method, @code{url-fetch},
6941 @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
6942 [name] [#:executable? #f]
6943 Return a fixed-output derivation that fetches data from @var{url} (a
6944 string, or a list of strings denoting alternate URLs), which is expected
6945 to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
6946 the file name is the base name of URL; optionally, @var{name} can
6947 specify a different file name. When @var{executable?} is true, make the
6948 downloaded file executable.
6950 When one of the URL starts with @code{mirror://}, then its host part is
6951 interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
6953 Alternatively, when URL starts with @code{file://}, return the
6954 corresponding file name in the store.
6957 Likewise, the @code{(guix git-download)} module defines the
6958 @code{git-fetch} origin method, which fetches data from a Git version
6959 control repository, and the @code{git-reference} data type to describe
6960 the repository and revision to fetch.
6962 @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
6963 Return a fixed-output derivation that fetches @var{ref}, a
6964 @code{<git-reference>} object. The output is expected to have recursive
6965 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
6966 the file name, or a generic name if @code{#f}.
6969 @deftp {Data Type} git-reference
6970 This data type represents a Git reference for @code{git-fetch} to
6975 The URL of the Git repository to clone.
6978 This string denotes either the commit to fetch (a hexadecimal string,
6979 either the full SHA1 commit or a ``short'' commit string; the latter is
6980 not recommended) or the tag to fetch.
6982 @item @code{recursive?} (default: @code{#f})
6983 This Boolean indicates whether to recursively fetch Git sub-modules.
6986 The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
6991 (url "https://git.savannah.gnu.org/git/hello.git")
6995 This is equivalent to the reference below, which explicitly names the
7000 (url "https://git.savannah.gnu.org/git/hello.git")
7001 (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
7005 For Mercurial repositories, the module @code{(guix hg-download)} defines
7006 the @code{hg-fetch} origin method and @code{hg-reference} data type for
7007 support of the Mercurial version control system.
7009 @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
7011 Return a fixed-output derivation that fetches @var{ref}, a
7012 @code{<hg-reference>} object. The output is expected to have recursive
7013 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7014 the file name, or a generic name if @code{#false}.
7017 @node Defining Package Variants
7018 @section Defining Package Variants
7020 @cindex customizing packages
7021 @cindex variants, of packages
7022 One of the nice things with Guix is that, given a package definition,
7023 you can easily @emph{derive} variants of that package---for a different
7024 upstream version, with different dependencies, different compilation
7025 options, and so on. Some of these custom packages can be defined
7026 straight from the command line (@pxref{Package Transformation Options}).
7027 This section describes how to define package variants in code. This can
7028 be useful in ``manifests'' (@pxref{profile-manifest,
7029 @option{--manifest}}) and in your own package collection
7030 (@pxref{Creating a Channel}), among others!
7032 @cindex inherit, for package definitions
7033 As discussed earlier, packages are first-class objects in the Scheme
7034 language. The @code{(guix packages)} module provides the @code{package}
7035 construct to define new package objects (@pxref{package Reference}).
7036 The easiest way to define a package variant is using the @code{inherit}
7037 keyword together with @code{package}. This allows you to inherit from a
7038 package definition while overriding the fields you want.
7040 For example, given the @code{hello} variable, which contains a
7041 definition for the current version of GNU@tie{}Hello, here's how you
7042 would define a variant for version 2.2 (released in 2006, it's
7046 (use-modules (gnu packages base)) ;for 'hello'
7054 (uri (string-append "mirror://gnu/hello/hello-" version
7058 "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
7061 The example above corresponds to what the @option{--with-source} package
7062 transformation option does. Essentially @code{hello-2.2} preserves all
7063 the fields of @code{hello}, except @code{version} and @code{source},
7064 which it overrides. Note that the original @code{hello} variable is
7065 still there, in the @code{(gnu packages base)} module, unchanged. When
7066 you define a custom package like this, you are really @emph{adding} a
7067 new package definition; the original one remains available.
7069 You can just as well define variants with a different set of
7070 dependencies than the original package. For example, the default
7071 @code{gdb} package depends on @code{guile}, but since that is an
7072 optional dependency, you can define a variant that removes that
7076 (use-modules (gnu packages gdb) ;for 'gdb'
7077 (srfi srfi-1)) ;for 'alist-delete'
7079 (define gdb-sans-guile
7082 (inputs (alist-delete "guile"
7083 (package-inputs gdb)))))
7086 The @code{alist-delete} call above removes the tuple from the
7087 @code{inputs} field that has @code{"guile"} as its first element
7088 (@pxref{SRFI-1 Association Lists,,, guile, GNU Guile Reference
7091 In some cases, you may find it useful to write functions
7092 (``procedures'', in Scheme parlance) that return a package based on some
7093 parameters. For example, consider the @code{luasocket} library for the
7094 Lua programming language. We want to create @code{luasocket} packages
7095 for major versions of Lua. One way to do that is to define a procedure
7096 that takes a Lua package and returns a @code{luasocket} package that
7100 (define (make-lua-socket name lua)
7101 ;; Return a luasocket package built with LUA.
7105 ;; several fields omitted
7108 (synopsis "Socket library for Lua")))
7110 (define-public lua5.1-socket
7111 (make-lua-socket "lua5.1-socket" lua-5.1))
7113 (define-public lua5.2-socket
7114 (make-lua-socket "lua5.2-socket" lua-5.2))
7117 Here we have defined packages @code{lua5.1-socket} and
7118 @code{lua5.2-socket} by calling @code{make-lua-socket} with different
7119 arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
7120 more info on procedures. Having top-level public definitions for these
7121 two packages means that they can be referred to from the command line
7122 (@pxref{Package Modules}).
7124 @cindex package transformations
7125 These are pretty simple package variants. As a convenience, the
7126 @code{(guix transformations)} module provides a high-level interface
7127 that directly maps to the more sophisticated package transformation
7128 options (@pxref{Package Transformation Options}):
7130 @deffn {Scheme Procedure} options->transformation @var{opts}
7131 Return a procedure that, when passed an object to build (package,
7132 derivation, etc.), applies the transformations specified by @var{opts} and returns
7133 the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
7136 ((with-branch . "guile-gcrypt=master")
7137 (without-tests . "libgcrypt"))
7140 Each symbol names a transformation and the corresponding string is an argument
7141 to that transformation.
7144 For instance, a manifest equivalent to this command:
7148 --with-branch=guile-gcrypt=master \
7149 --with-debug-info=zlib
7153 ... would look like this:
7156 (use-modules (guix transformations))
7159 ;; The package transformation procedure.
7160 (options->transformation
7161 '((with-branch . "guile-gcrypt=master")
7162 (with-debug-info . "zlib"))))
7165 (list (transform (specification->package "guix"))))
7168 @cindex input rewriting
7169 @cindex dependency graph rewriting
7170 The @code{options->transformation} procedure is convenient, but it's
7171 perhaps also not as flexible as you may like. How is it implemented?
7172 The astute reader probably noticed that most package transformation
7173 options go beyond the superficial changes shown in the first examples of
7174 this section: they involve @dfn{input rewriting}, whereby the dependency
7175 graph of a package is rewritten by replacing specific inputs by others.
7177 Dependency graph rewriting, for the purposes of swapping packages in the
7178 graph, is what the @code{package-input-rewriting} procedure in
7179 @code{(guix packages)} implements.
7181 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
7182 [@var{rewrite-name}] [#:deep? #t]
7183 Return a procedure that, when passed a package, replaces its direct and
7184 indirect dependencies, including implicit inputs when @var{deep?} is
7185 true, according to @var{replacements}. @var{replacements} is a list of
7186 package pairs; the first element of each pair is the package to replace,
7187 and the second one is the replacement.
7189 Optionally, @var{rewrite-name} is a one-argument procedure that takes
7190 the name of a package and returns its new name after rewrite.
7194 Consider this example:
7197 (define libressl-instead-of-openssl
7198 ;; This is a procedure to replace OPENSSL by LIBRESSL,
7200 (package-input-rewriting `((,openssl . ,libressl))))
7202 (define git-with-libressl
7203 (libressl-instead-of-openssl git))
7207 Here we first define a rewriting procedure that replaces @var{openssl}
7208 with @var{libressl}. Then we use it to define a @dfn{variant} of the
7209 @var{git} package that uses @var{libressl} instead of @var{openssl}.
7210 This is exactly what the @option{--with-input} command-line option does
7211 (@pxref{Package Transformation Options, @option{--with-input}}).
7213 The following variant of @code{package-input-rewriting} can match packages to
7214 be replaced by name rather than by identity.
7216 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
7217 Return a procedure that, given a package, applies the given
7218 @var{replacements} to all the package graph, including implicit inputs
7219 unless @var{deep?} is false. @var{replacements} is a list of
7220 spec/procedures pair; each spec is a package specification such as
7221 @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
7222 package and returns a replacement for that package.
7225 The example above could be rewritten this way:
7228 (define libressl-instead-of-openssl
7229 ;; Replace all the packages called "openssl" with LibreSSL.
7230 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
7233 The key difference here is that, this time, packages are matched by spec and
7234 not by identity. In other words, any package in the graph that is called
7235 @code{openssl} will be replaced.
7237 A more generic procedure to rewrite a package dependency graph is
7238 @code{package-mapping}: it supports arbitrary changes to nodes in the
7241 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
7242 Return a procedure that, given a package, applies @var{proc} to all the packages
7243 depended on and returns the resulting package. The procedure stops recursion
7244 when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
7245 applied to implicit inputs as well.
7250 @section Build Systems
7252 @cindex build system
7253 Each package definition specifies a @dfn{build system} and arguments for
7254 that build system (@pxref{Defining Packages}). This @code{build-system}
7255 field represents the build procedure of the package, as well as implicit
7256 dependencies of that build procedure.
7258 Build systems are @code{<build-system>} objects. The interface to
7259 create and manipulate them is provided by the @code{(guix build-system)}
7260 module, and actual build systems are exported by specific modules.
7262 @cindex bag (low-level package representation)
7263 Under the hood, build systems first compile package objects to
7264 @dfn{bags}. A @dfn{bag} is like a package, but with less
7265 ornamentation---in other words, a bag is a lower-level representation of
7266 a package, which includes all the inputs of that package, including some
7267 that were implicitly added by the build system. This intermediate
7268 representation is then compiled to a derivation (@pxref{Derivations}).
7269 The @code{package-with-c-toolchain} is an example of a way to change the
7270 implicit inputs that a package's build system pulls in (@pxref{package
7271 Reference, @code{package-with-c-toolchain}}).
7273 Build systems accept an optional list of @dfn{arguments}. In package
7274 definitions, these are passed @i{via} the @code{arguments} field
7275 (@pxref{Defining Packages}). They are typically keyword arguments
7276 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
7277 Guile Reference Manual}). The value of these arguments is usually
7278 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
7279 by the daemon (@pxref{Derivations}).
7281 The main build system is @code{gnu-build-system}, which implements the
7282 standard build procedure for GNU and many other packages. It
7283 is provided by the @code{(guix build-system gnu)} module.
7285 @defvr {Scheme Variable} gnu-build-system
7286 @code{gnu-build-system} represents the GNU Build System, and variants
7287 thereof (@pxref{Configuration, configuration and makefile conventions,,
7288 standards, GNU Coding Standards}).
7290 @cindex build phases
7291 In a nutshell, packages using it are configured, built, and installed with
7292 the usual @code{./configure && make && make check && make install}
7293 command sequence. In practice, a few additional steps are often needed.
7294 All these steps are split up in separate @dfn{phases}.
7295 @xref{Build Phases}, for more info on build phases and ways to customize
7298 In addition, this build system ensures that the ``standard'' environment
7299 for GNU packages is available. This includes tools such as GCC, libc,
7300 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
7301 build-system gnu)} module for a complete list). We call these the
7302 @dfn{implicit inputs} of a package, because package definitions do not
7303 have to mention them.
7305 This build system supports a number of keyword arguments, which can be
7306 passed @i{via} the @code{arguments} field of a package. Here are some
7307 of the main parameters:
7311 This argument specifies build-side code that evaluates to an alist of
7312 build phases. @xref{Build Phases}, for more information.
7314 @item #:configure-flags
7315 This is a list of flags (strings) passed to the @command{configure}
7316 script. @xref{Defining Packages}, for an example.
7319 This list of strings contains flags passed as arguments to
7320 @command{make} invocations in the @code{build}, @code{check}, and
7321 @code{install} phases.
7323 @item #:out-of-source?
7324 This Boolean, @code{#f} by default, indicates whether to run builds in a
7325 build directory separate from the source tree.
7327 When it is true, the @code{configure} phase creates a separate build
7328 directory, changes to that directory, and runs the @code{configure}
7329 script from there. This is useful for packages that require it, such as
7333 This Boolean, @code{#t} by default, indicates whether the @code{check}
7334 phase should run the package's test suite.
7337 This string, @code{"check"} by default, gives the name of the makefile
7338 target used by the @code{check} phase.
7340 @item #:parallel-build?
7341 @itemx #:parallel-tests?
7342 These Boolean values specify whether to build, respectively run the test
7343 suite, in parallel, with the @code{-j} flag of @command{make}. When
7344 they are true, @code{make} is passed @code{-j@var{n}}, where @var{n} is
7345 the number specified as the @option{--cores} option of
7346 @command{guix-daemon} or that of the @command{guix} client command
7347 (@pxref{Common Build Options, @option{--cores}}).
7349 @cindex RUNPATH, validation
7350 @item #:validate-runpath?
7351 This Boolean, @code{#t} by default, determines whether to ``validate''
7352 the @code{RUNPATH} of ELF binaries (@code{.so} shared libraries as well
7353 as executables) previously installed by the @code{install} phase.
7355 This validation step consists in making sure that all the shared
7356 libraries needed by an ELF binaries, which are listed as
7357 @code{DT_NEEDED} entries in its @code{PT_DYNAMIC} segment, appear in the
7358 @code{DT_RUNPATH} entry of that binary. In other words, it ensures that
7359 running or using those binaries will not result in a ``file not found''
7360 error at run time. @xref{Options, @option{-rpath},, ld, The GNU
7361 Linker}, for more information on @code{RUNPATH}.
7363 @item #:substitutable?
7364 This Boolean, @code{#t} by default, tells whether the package outputs
7365 should be substitutable---i.e., whether users should be able to obtain
7366 substitutes for them instead of building locally (@pxref{Substitutes}).
7368 @item #:allowed-references
7369 @itemx #:disallowed-references
7370 When true, these arguments must be a list of dependencies that must not
7371 appear among the references of the build results. If, upon build
7372 completion, some of these references are retained, the build process
7375 This is useful to ensure that a package does not erroneously keep a
7376 reference to some of it build-time inputs, in cases where doing so
7377 would, for example, unnecessarily increase its size (@pxref{Invoking
7381 Most other build systems support these keyword arguments.
7384 Other @code{<build-system>} objects are defined to support other
7385 conventions and tools used by free software packages. They inherit most
7386 of @code{gnu-build-system}, and differ mainly in the set of inputs
7387 implicitly added to the build process, and in the list of phases
7388 executed. Some of these build systems are listed below.
7390 @defvr {Scheme Variable} ant-build-system
7391 This variable is exported by @code{(guix build-system ant)}. It
7392 implements the build procedure for Java packages that can be built with
7393 @url{https://ant.apache.org/, Ant build tool}.
7395 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
7396 provided by the @code{icedtea} package to the set of inputs. Different
7397 packages can be specified with the @code{#:ant} and @code{#:jdk}
7398 parameters, respectively.
7400 When the original package does not provide a suitable Ant build file,
7401 the parameter @code{#:jar-name} can be used to generate a minimal Ant
7402 build file @file{build.xml} with tasks to build the specified jar
7403 archive. In this case the parameter @code{#:source-dir} can be used to
7404 specify the source sub-directory, defaulting to ``src''.
7406 The @code{#:main-class} parameter can be used with the minimal ant
7407 buildfile to specify the main class of the resulting jar. This makes the
7408 jar file executable. The @code{#:test-include} parameter can be used to
7409 specify the list of junit tests to run. It defaults to
7410 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
7411 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
7412 because abstract classes cannot be run as tests.
7414 The parameter @code{#:build-target} can be used to specify the Ant task
7415 that should be run during the @code{build} phase. By default the
7416 ``jar'' task will be run.
7420 @defvr {Scheme Variable} android-ndk-build-system
7421 @cindex Android distribution
7422 @cindex Android NDK build system
7423 This variable is exported by @code{(guix build-system android-ndk)}. It
7424 implements a build procedure for Android NDK (native development kit)
7425 packages using a Guix-specific build process.
7427 The build system assumes that packages install their public interface
7428 (header) files to the subdirectory @file{include} of the @code{out} output and
7429 their libraries to the subdirectory @file{lib} the @code{out} output.
7431 It's also assumed that the union of all the dependencies of a package
7432 has no conflicting files.
7434 For the time being, cross-compilation is not supported - so right now
7435 the libraries and header files are assumed to be host tools.
7439 @defvr {Scheme Variable} asdf-build-system/source
7440 @defvrx {Scheme Variable} asdf-build-system/sbcl
7441 @defvrx {Scheme Variable} asdf-build-system/ecl
7443 These variables, exported by @code{(guix build-system asdf)}, implement
7444 build procedures for Common Lisp packages using
7445 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
7446 definition facility for Common Lisp programs and libraries.
7448 The @code{asdf-build-system/source} system installs the packages in
7449 source form, and can be loaded using any common lisp implementation, via
7450 ASDF@. The others, such as @code{asdf-build-system/sbcl}, install binary
7451 systems in the format which a particular implementation understands.
7452 These build systems can also be used to produce executable programs, or
7453 lisp images which contain a set of packages pre-loaded.
7455 The build system uses naming conventions. For binary packages, the
7456 package name should be prefixed with the lisp implementation, such as
7457 @code{sbcl-} for @code{asdf-build-system/sbcl}.
7459 Additionally, the corresponding source package should be labeled using
7460 the same convention as python packages (see @ref{Python Modules}), using
7461 the @code{cl-} prefix.
7463 In order to create executable programs and images, the build-side
7464 procedures @code{build-program} and @code{build-image} can be used.
7465 They should be called in a build phase after the
7466 @code{create-asdf-configuration} phase, so that the system which was
7467 just built can be used within the resulting image. @code{build-program}
7468 requires a list of Common Lisp expressions to be passed as the
7469 @code{#:entry-program} argument.
7471 By default, all the @file{.asd} files present in the sources are read to
7472 find system definitions. The @code{#:asd-files} parameter can be used
7473 to specify the list of @file{.asd} files to read. Furthermore, if the
7474 package defines a system for its tests in a separate file, it will be
7475 loaded before the tests are run if it is specified by the
7476 @code{#:test-asd-file} parameter. If it is not set, the files
7477 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
7478 and @code{test.asd} will be tried if they exist.
7480 If for some reason the package must be named in a different way than the
7481 naming conventions suggest, or if several systems must be compiled, the
7482 @code{#:asd-systems} parameter can be used to specify the list of system
7487 @defvr {Scheme Variable} cargo-build-system
7488 @cindex Rust programming language
7489 @cindex Cargo (Rust build system)
7490 This variable is exported by @code{(guix build-system cargo)}. It
7491 supports builds of packages using Cargo, the build tool of the
7492 @uref{https://www.rust-lang.org, Rust programming language}.
7494 It adds @code{rustc} and @code{cargo} to the set of inputs.
7495 A different Rust package can be specified with the @code{#:rust} parameter.
7497 Regular cargo dependencies should be added to the package definition similarly
7498 to other packages; those needed only at build time to native-inputs, others to
7499 inputs. If you need to add source-only crates then you should add them to via
7500 the @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
7501 spec can be a package or a source definition. Note that the spec must
7502 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
7503 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
7504 should be added to the package definition via the
7505 @code{#:cargo-development-inputs} parameter.
7507 In its @code{configure} phase, this build system will make any source inputs
7508 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
7509 parameters available to cargo. It will also remove an included
7510 @code{Cargo.lock} file to be recreated by @code{cargo} during the
7511 @code{build} phase. The @code{package} phase will run @code{cargo package}
7512 to create a source crate for future use. The @code{install} phase installs
7513 the binaries defined by the crate. Unless @code{install-source? #f} is
7514 defined it will also install a source crate repository of itself and unpacked
7515 sources, to ease in future hacking on rust packages.
7518 @defvr {Scheme Variable} chicken-build-system
7519 This variable is exported by @code{(guix build-system chicken)}. It
7520 builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
7521 ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
7522 gets compiled by a C compiler, in this case GCC.
7524 This build system adds @code{chicken} to the package inputs, as well as
7525 the packages of @code{gnu-build-system}.
7527 The build system can't (yet) deduce the egg's name automatically, so just like
7528 with @code{go-build-system} and its @code{#:import-path}, you should define
7529 @code{#:egg-name} in the package's @code{arguments} field.
7531 For example, if you are packaging the @code{srfi-1} egg:
7534 (arguments '(#:egg-name "srfi-1"))
7537 Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
7538 because CHICKEN doesn't embed absolute references in compiled eggs.
7539 Test dependencies should go to @code{native-inputs}, as usual.
7542 @defvr {Scheme Variable} copy-build-system
7543 This variable is exported by @code{(guix build-system copy)}. It
7544 supports builds of simple packages that don't require much compiling,
7545 mostly just moving files around.
7547 It adds much of the @code{gnu-build-system} packages to the set of
7548 inputs. Because of this, the @code{copy-build-system} does not require
7549 all the boilerplate code often needed for the
7550 @code{trivial-build-system}.
7552 To further simplify the file installation process, an
7553 @code{#:install-plan} argument is exposed to let the packager specify
7554 which files go where. The install plan is a list of @code{(@var{source}
7555 @var{target} [@var{filters}])}. @var{filters} are optional.
7558 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
7560 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
7561 @item Otherwise install @var{source} as @var{target}.
7564 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
7565 the trailing slash of @var{target} is implied with the same meaning
7568 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
7569 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
7570 @code{#:exclude-regexp}, only select files are installed depending on
7571 the filters. Each filters is specified by a list of strings.
7573 @item With @code{#:include}, install all the files which the path suffix matches
7574 at least one of the elements in the given list.
7575 @item With @code{#:include-regexp}, install all the files which the
7576 subpaths match at least one of the regular expressions in the given
7578 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
7579 are the complement of their inclusion counterpart. Without @code{#:include} flags,
7580 install all files but those matching the exclusion filters.
7581 If both inclusions and exclusions are specified, the exclusions are done
7582 on top of the inclusions.
7585 In all cases, the paths relative to @var{source} are preserved within
7592 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
7593 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
7594 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
7595 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
7596 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
7597 @file{share/my-app/sub/file}.
7598 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
7599 @file{share/my-app/file}.
7604 @cindex Clojure (programming language)
7605 @cindex simple Clojure build system
7606 @defvr {Scheme Variable} clojure-build-system
7607 This variable is exported by @code{(guix build-system clojure)}. It implements
7608 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
7609 using plain old @code{compile} in Clojure. Cross-compilation is not supported
7612 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
7613 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
7614 @code{#:zip} parameters, respectively.
7616 A list of source directories, test directories and jar names can be specified
7617 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
7618 parameters, respectively. Compile directory and main class can be specified
7619 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
7620 Other parameters are documented below.
7622 This build system is an extension of @code{ant-build-system}, but with the
7623 following phases changed:
7628 This phase calls @code{compile} in Clojure to compile source files and runs
7629 @command{jar} to create jars from both source files and compiled files
7630 according to the include list and exclude list specified in
7631 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
7632 has priority over the include list. These lists consist of symbols
7633 representing Clojure libraries or the special keyword @code{#:all} representing
7634 all Clojure libraries found under the source directories. The parameter
7635 @code{#:omit-source?} decides if source should be included into the jars.
7638 This phase runs tests according to the include list and exclude list specified
7639 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
7640 meanings are analogous to that of @code{#:aot-include} and
7641 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
7642 stands for all Clojure libraries found under the test directories. The
7643 parameter @code{#:tests?} decides if tests should be run.
7646 This phase installs all jars built previously.
7649 Apart from the above, this build system also contains an additional phase:
7654 This phase installs all top-level files with base name matching
7655 @code{%doc-regex}. A different regex can be specified with the
7656 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
7657 directories specified in @code{#:doc-dirs} are installed as well.
7661 @defvr {Scheme Variable} cmake-build-system
7662 This variable is exported by @code{(guix build-system cmake)}. It
7663 implements the build procedure for packages using the
7664 @url{https://www.cmake.org, CMake build tool}.
7666 It automatically adds the @code{cmake} package to the set of inputs.
7667 Which package is used can be specified with the @code{#:cmake}
7670 The @code{#:configure-flags} parameter is taken as a list of flags
7671 passed to the @command{cmake} command. The @code{#:build-type}
7672 parameter specifies in abstract terms the flags passed to the compiler;
7673 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
7674 debugging information''), which roughly means that code is compiled with
7675 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
7678 @defvr {Scheme Variable} dune-build-system
7679 This variable is exported by @code{(guix build-system dune)}. It
7680 supports builds of packages using @uref{https://dune.build/, Dune}, a build
7681 tool for the OCaml programming language. It is implemented as an extension
7682 of the @code{ocaml-build-system} which is described below. As such, the
7683 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
7686 It automatically adds the @code{dune} package to the set of inputs.
7687 Which package is used can be specified with the @code{#:dune}
7690 There is no @code{configure} phase because dune packages typically don't
7691 need to be configured. The @code{#:build-flags} parameter is taken as a
7692 list of flags passed to the @code{dune} command during the build.
7694 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
7695 command instead of the more recent @code{dune} command while building
7696 a package. Its default value is @code{#f}.
7698 The @code{#:package} parameter can be passed to specify a package name, which
7699 is useful when a package contains multiple packages and you want to build
7700 only one of them. This is equivalent to passing the @code{-p} argument to
7704 @defvr {Scheme Variable} go-build-system
7705 This variable is exported by @code{(guix build-system go)}. It
7706 implements a build procedure for Go packages using the standard
7707 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
7708 Go build mechanisms}.
7710 The user is expected to provide a value for the key @code{#:import-path}
7711 and, in some cases, @code{#:unpack-path}. The
7712 @url{https://golang.org/doc/code.html#ImportPaths, import path}
7713 corresponds to the file system path expected by the package's build
7714 scripts and any referring packages, and provides a unique way to
7715 refer to a Go package. It is typically based on a combination of the
7716 package source code's remote URI and file system hierarchy structure. In
7717 some cases, you will need to unpack the package's source code to a
7718 different directory structure than the one indicated by the import path,
7719 and @code{#:unpack-path} should be used in such cases.
7721 Packages that provide Go libraries should install their source code into
7722 the built output. The key @code{#:install-source?}, which defaults to
7723 @code{#t}, controls whether or not the source code is installed. It can
7724 be set to @code{#f} for packages that only provide executable files.
7727 @defvr {Scheme Variable} glib-or-gtk-build-system
7728 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
7729 is intended for use with packages making use of GLib or GTK+.
7731 This build system adds the following two phases to the ones defined by
7732 @code{gnu-build-system}:
7735 @item glib-or-gtk-wrap
7736 The phase @code{glib-or-gtk-wrap} ensures that programs in
7737 @file{bin/} are able to find GLib ``schemas'' and
7738 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
7739 modules}. This is achieved by wrapping the programs in launch scripts
7740 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
7741 environment variables.
7743 It is possible to exclude specific package outputs from that wrapping
7744 process by listing their names in the
7745 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
7746 when an output is known not to contain any GLib or GTK+ binaries, and
7747 where wrapping would gratuitously add a dependency of that output on
7750 @item glib-or-gtk-compile-schemas
7751 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
7752 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
7753 GSettings schemas} of GLib are compiled. Compilation is performed by the
7754 @command{glib-compile-schemas} program. It is provided by the package
7755 @code{glib:bin} which is automatically imported by the build system.
7756 The @code{glib} package providing @command{glib-compile-schemas} can be
7757 specified with the @code{#:glib} parameter.
7760 Both phases are executed after the @code{install} phase.
7763 @defvr {Scheme Variable} guile-build-system
7764 This build system is for Guile packages that consist exclusively of Scheme
7765 code and that are so lean that they don't even have a makefile, let alone a
7766 @file{configure} script. It compiles Scheme code using @command{guild
7767 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
7768 installs the @file{.scm} and @file{.go} files in the right place. It also
7769 installs documentation.
7771 This build system supports cross-compilation by using the
7772 @option{--target} option of @samp{guild compile}.
7774 Packages built with @code{guile-build-system} must provide a Guile package in
7775 their @code{native-inputs} field.
7778 @defvr {Scheme Variable} julia-build-system
7779 This variable is exported by @code{(guix build-system julia)}. It
7780 implements the build procedure used by @uref{https://julialang.org/,
7781 julia} packages, which essentially is similar to running @samp{julia -e
7782 'using Pkg; Pkg.add(package)'} in an environment where
7783 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
7784 Tests are run by calling @code{/test/runtests.jl}.
7786 The Julia package name is read from the file @file{Project.toml}. This
7787 value can be overridden by passing the argument @code{#:julia-package-name}
7788 (which must be correctly capitalized).
7790 Julia packages usually manage their binary dependencies via
7791 @code{JLLWrappers.jl}, a Julia package that creates a module (named
7792 after the wrapped library followed by @code{_jll.jl}.
7794 To add the binary path @code{_jll.jl} packages, you need to patch the
7795 files under @file{src/wrappers/}, replacing the call to the macro
7796 @code{JLLWrappers.@@generate_wrapper_header}, adding as a second
7797 argument containing the store path the binary.
7799 As an example, in the MbedTLS Julia package, we add a build phase
7800 (@pxref{Build Phases}) to insert the absolute file name of the wrapped
7804 (add-after 'unpack 'override-binary-path
7805 (lambda* (#:key inputs #:allow-other-keys)
7806 (for-each (lambda (wrapper)
7807 (substitute* wrapper
7808 (("generate_wrapper_header.*")
7810 "generate_wrapper_header(\"MbedTLS\", \""
7811 (assoc-ref inputs "mbedtls-apache") "\")\n"))))
7812 ;; There's a Julia file for each platform, override them all.
7813 (find-files "src/wrappers/" "\\.jl$"))))
7816 Some older packages that aren't using @file{Package.toml} yet, will require
7817 this file to be created, too. The function @code{julia-create-package-toml}
7818 helps creating the file. You need to pass the outputs and the source of the
7819 package, its name (the same as the @code{file-name} parameter), the package
7820 uuid, the package version, and a list of dependencies specified by their name
7824 @defvr {Scheme Variable} maven-build-system
7825 This variable is exported by @code{(guix build-system maven)}. It implements
7826 a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
7827 is a dependency and lifecycle management tool for Java. A user of Maven
7828 specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
7829 When Maven does not have one of the dependencies or plugins in its repository,
7830 it will download them and use them to build the package.
7832 The maven build system ensures that maven will not try to download any
7833 dependency by running in offline mode. Maven will fail if a dependency is
7834 missing. Before running Maven, the @file{pom.xml} (and subprojects) are
7835 modified to specify the version of dependencies and plugins that match the
7836 versions available in the guix build environment. Dependencies and plugins
7837 must be installed in the fake maven repository at @file{lib/m2}, and are
7838 symlinked into a proper repository before maven is run. Maven is instructed
7839 to use that repository for the build and installs built artifacts there.
7840 Changed files are copied to the @file{lib/m2} directory of the package output.
7842 You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
7843 or let the build system use the default @file{pom.xml} file in the sources.
7845 In case you need to specify a dependency's version manually, you can use the
7846 @code{#:local-packages} argument. It takes an association list where the key
7847 is the groupId of the package and its value is an association list where the
7848 key is the artifactId of the package and its value is the version you want to
7849 override in the @file{pom.xml}.
7851 Some packages use dependencies or plugins that are not useful at runtime nor
7852 at build time in Guix. You can alter the @file{pom.xml} file to remove them
7853 using the @code{#:exclude} argument. Its value is an association list where
7854 the key is the groupId of the plugin or dependency you want to remove, and
7855 the value is a list of artifactId you want to remove.
7857 You can override the default @code{jdk} and @code{maven} packages with the
7858 corresponding argument, @code{#:jdk} and @code{#:maven}.
7860 The @code{#:maven-plugins} argument is a list of maven plugins used during
7861 the build, with the same format as the @code{inputs} fields of the package
7862 declaration. Its default value is @code{(default-maven-plugins)} which is
7866 @defvr {Scheme Variable} minify-build-system
7867 This variable is exported by @code{(guix build-system minify)}. It
7868 implements a minification procedure for simple JavaScript packages.
7870 It adds @code{uglify-js} to the set of inputs and uses it to compress
7871 all JavaScript files in the @file{src} directory. A different minifier
7872 package can be specified with the @code{#:uglify-js} parameter, but it
7873 is expected that the package writes the minified code to the standard
7876 When the input JavaScript files are not all located in the @file{src}
7877 directory, the parameter @code{#:javascript-files} can be used to
7878 specify a list of file names to feed to the minifier.
7881 @defvr {Scheme Variable} ocaml-build-system
7882 This variable is exported by @code{(guix build-system ocaml)}. It implements
7883 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
7884 of choosing the correct set of commands to run for each package. OCaml
7885 packages can expect many different commands to be run. This build system will
7888 When the package has a @file{setup.ml} file present at the top-level, it will
7889 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
7890 @code{ocaml setup.ml -install}. The build system will assume that this file
7891 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
7892 care of setting the prefix and enabling tests if they are not disabled. You
7893 can pass configure and build flags with the @code{#:configure-flags} and
7894 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
7895 set of flags used to enable tests. The @code{#:use-make?} key can be used to
7896 bypass this system in the build and install phases.
7898 When the package has a @file{configure} file, it is assumed that it is a
7899 hand-made configure script that requires a different argument format than
7900 in the @code{gnu-build-system}. You can add more flags with the
7901 @code{#:configure-flags} key.
7903 When the package has a @file{Makefile} file (or @code{#:use-make?} is
7904 @code{#t}), it will be used and more flags can be passed to the build and
7905 install phases with the @code{#:make-flags} key.
7907 Finally, some packages do not have these files and use a somewhat standard
7908 location for its build system. In that case, the build system will run
7909 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
7910 providing the path to the required findlib module. Additional flags can
7911 be passed via the @code{#:build-flags} key. Install is taken care of by
7912 @command{opam-installer}. In this case, the @code{opam} package must
7913 be added to the @code{native-inputs} field of the package definition.
7915 Note that most OCaml packages assume they will be installed in the same
7916 directory as OCaml, which is not what we want in guix. In particular, they
7917 will install @file{.so} files in their module's directory, which is usually
7918 fine because it is in the OCaml compiler directory. In guix though, these
7919 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
7920 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
7921 @file{.so} libraries should be installed.
7924 @defvr {Scheme Variable} python-build-system
7925 This variable is exported by @code{(guix build-system python)}. It
7926 implements the more or less standard build procedure used by Python
7927 packages, which consists in running @code{python setup.py build} and
7928 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
7930 For packages that install stand-alone Python programs under @code{bin/},
7931 it takes care of wrapping these programs so that their @env{PYTHONPATH}
7932 environment variable points to all the Python libraries they depend on.
7934 Which Python package is used to perform the build can be specified with
7935 the @code{#:python} parameter. This is a useful way to force a package
7936 to be built for a specific version of the Python interpreter, which
7937 might be necessary if the package is only compatible with a single
7938 interpreter version.
7940 By default guix calls @code{setup.py} under control of
7941 @code{setuptools}, much like @command{pip} does. Some packages are not
7942 compatible with setuptools (and pip), thus you can disable this by
7943 setting the @code{#:use-setuptools?} parameter to @code{#f}.
7946 @defvr {Scheme Variable} perl-build-system
7947 This variable is exported by @code{(guix build-system perl)}. It
7948 implements the standard build procedure for Perl packages, which either
7949 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
7950 followed by @code{Build} and @code{Build install}; or in running
7951 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
7952 @code{make} and @code{make install}, depending on which of
7953 @code{Build.PL} or @code{Makefile.PL} is present in the package
7954 distribution. Preference is given to the former if both @code{Build.PL}
7955 and @code{Makefile.PL} exist in the package distribution. This
7956 preference can be reversed by specifying @code{#t} for the
7957 @code{#:make-maker?} parameter.
7959 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
7960 passes flags specified by the @code{#:make-maker-flags} or
7961 @code{#:module-build-flags} parameter, respectively.
7963 Which Perl package is used can be specified with @code{#:perl}.
7966 @defvr {Scheme Variable} renpy-build-system
7967 This variable is exported by @code{(guix build-system renpy)}. It implements
7968 the more or less standard build procedure used by Ren'py games, which consists
7969 of loading @code{#:game} once, thereby creating bytecode for it.
7971 It further creates a wrapper script in @code{bin/} and a desktop entry in
7972 @code{share/applications}, both of which can be used to launch the game.
7974 Which Ren'py package is used can be specified with @code{#:renpy}.
7975 Games can also be installed in outputs other than ``out'' by using
7979 @defvr {Scheme Variable} qt-build-system
7980 This variable is exported by @code{(guix build-system qt)}. It
7981 is intended for use with applications using Qt or KDE.
7983 This build system adds the following two phases to the ones defined by
7984 @code{cmake-build-system}:
7988 The phase @code{check-setup} prepares the environment for running
7989 the checks as commonly used by Qt test programs.
7990 For now this only sets some environment variables:
7991 @code{QT_QPA_PLATFORM=offscreen},
7992 @code{DBUS_FATAL_WARNINGS=0} and
7993 @code{CTEST_OUTPUT_ON_FAILURE=1}.
7995 This phase is added before the @code{check} phase.
7996 It's a separate phase to ease adjusting if necessary.
7999 The phase @code{qt-wrap}
8000 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
8001 and output. In case some path is found, all programs in the output's
8002 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
8003 are wrapped in scripts defining the necessary environment variables.
8005 It is possible to exclude specific package outputs from that wrapping process
8006 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
8007 This is useful when an output is known not to contain any Qt binaries, and
8008 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
8011 This phase is added after the @code{install} phase.
8015 @defvr {Scheme Variable} r-build-system
8016 This variable is exported by @code{(guix build-system r)}. It
8017 implements the build procedure used by @uref{https://r-project.org, R}
8018 packages, which essentially is little more than running @samp{R CMD
8019 INSTALL --library=/gnu/store/@dots{}} in an environment where
8020 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
8021 run after installation using the R function
8022 @code{tools::testInstalledPackage}.
8025 @defvr {Scheme Variable} rakudo-build-system
8026 This variable is exported by @code{(guix build-system rakudo)}. It
8027 implements the build procedure used by @uref{https://rakudo.org/,
8028 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
8029 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
8030 installs the binaries, library files and the resources, as well as wrap
8031 the files under the @code{bin/} directory. Tests can be skipped by
8032 passing @code{#f} to the @code{tests?} parameter.
8034 Which rakudo package is used can be specified with @code{rakudo}.
8035 Which perl6-tap-harness package used for the tests can be specified with
8036 @code{#:prove6} or removed by passing @code{#f} to the
8037 @code{with-prove6?} parameter.
8038 Which perl6-zef package used for tests and installing can be specified
8039 with @code{#:zef} or removed by passing @code{#f} to the
8040 @code{with-zef?} parameter.
8043 @defvr {Scheme Variable} texlive-build-system
8044 This variable is exported by @code{(guix build-system texlive)}. It is
8045 used to build TeX packages in batch mode with a specified engine. The
8046 build system sets the @env{TEXINPUTS} variable to find all TeX source
8047 files in the inputs.
8049 By default it runs @code{luatex} on all files ending on @code{ins}. A
8050 different engine and format can be specified with the
8051 @code{#:tex-format} argument. Different build targets can be specified
8052 with the @code{#:build-targets} argument, which expects a list of file
8053 names. The build system adds only @code{texlive-bin} and
8054 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
8055 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
8056 and @code{#:texlive-latex-base}, respectively.
8058 The @code{#:tex-directory} parameter tells the build system where to
8059 install the built files under the texmf tree.
8062 @defvr {Scheme Variable} ruby-build-system
8063 This variable is exported by @code{(guix build-system ruby)}. It
8064 implements the RubyGems build procedure used by Ruby packages, which
8065 involves running @code{gem build} followed by @code{gem install}.
8067 The @code{source} field of a package that uses this build system
8068 typically references a gem archive, since this is the format that Ruby
8069 developers use when releasing their software. The build system unpacks
8070 the gem archive, potentially patches the source, runs the test suite,
8071 repackages the gem, and installs it. Additionally, directories and
8072 tarballs may be referenced to allow building unreleased gems from Git or
8073 a traditional source release tarball.
8075 Which Ruby package is used can be specified with the @code{#:ruby}
8076 parameter. A list of additional flags to be passed to the @command{gem}
8077 command can be specified with the @code{#:gem-flags} parameter.
8080 @defvr {Scheme Variable} waf-build-system
8081 This variable is exported by @code{(guix build-system waf)}. It
8082 implements a build procedure around the @code{waf} script. The common
8083 phases---@code{configure}, @code{build}, and @code{install}---are
8084 implemented by passing their names as arguments to the @code{waf}
8087 The @code{waf} script is executed by the Python interpreter. Which
8088 Python package is used to run the script can be specified with the
8089 @code{#:python} parameter.
8092 @defvr {Scheme Variable} scons-build-system
8093 This variable is exported by @code{(guix build-system scons)}. It
8094 implements the build procedure used by the SCons software construction
8095 tool. This build system runs @code{scons} to build the package,
8096 @code{scons test} to run tests, and then @code{scons install} to install
8099 Additional flags to be passed to @code{scons} can be specified with the
8100 @code{#:scons-flags} parameter. The default build and install targets
8101 can be overridden with @code{#:build-targets} and
8102 @code{#:install-targets} respectively. The version of Python used to
8103 run SCons can be specified by selecting the appropriate SCons package
8104 with the @code{#:scons} parameter.
8107 @defvr {Scheme Variable} haskell-build-system
8108 This variable is exported by @code{(guix build-system haskell)}. It
8109 implements the Cabal build procedure used by Haskell packages, which
8110 involves running @code{runhaskell Setup.hs configure
8111 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
8112 Instead of installing the package by running @code{runhaskell Setup.hs
8113 install}, to avoid trying to register libraries in the read-only
8114 compiler store directory, the build system uses @code{runhaskell
8115 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
8116 addition, the build system generates the package documentation by
8117 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
8118 is passed. Optional Haddock parameters can be passed with the help of
8119 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
8120 not found, the build system looks for @code{Setup.lhs} instead.
8122 Which Haskell compiler is used can be specified with the @code{#:haskell}
8123 parameter which defaults to @code{ghc}.
8126 @defvr {Scheme Variable} dub-build-system
8127 This variable is exported by @code{(guix build-system dub)}. It
8128 implements the Dub build procedure used by D packages, which
8129 involves running @code{dub build} and @code{dub run}.
8130 Installation is done by copying the files manually.
8132 Which D compiler is used can be specified with the @code{#:ldc}
8133 parameter which defaults to @code{ldc}.
8136 @anchor{emacs-build-system}
8137 @defvr {Scheme Variable} emacs-build-system
8138 This variable is exported by @code{(guix build-system emacs)}. It
8139 implements an installation procedure similar to the packaging system
8140 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
8142 It first creates the @code{@code{package}-autoloads.el} file, then it
8143 byte compiles all Emacs Lisp files. Differently from the Emacs
8144 packaging system, the Info documentation files are moved to the standard
8145 documentation directory and the @file{dir} file is deleted. The Elisp
8146 package files are installed directly under @file{share/emacs/site-lisp}.
8149 @defvr {Scheme Variable} font-build-system
8150 This variable is exported by @code{(guix build-system font)}. It
8151 implements an installation procedure for font packages where upstream
8152 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
8153 need to be copied into place. It copies font files to standard
8154 locations in the output directory.
8157 @defvr {Scheme Variable} meson-build-system
8158 This variable is exported by @code{(guix build-system meson)}. It
8159 implements the build procedure for packages that use
8160 @url{https://mesonbuild.com, Meson} as their build system.
8162 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
8163 of inputs, and they can be changed with the parameters @code{#:meson}
8164 and @code{#:ninja} if needed. The default Meson is
8165 @code{meson-for-build}, which is special because it doesn't clear the
8166 @code{RUNPATH} of binaries and libraries when they are installed.
8168 This build system is an extension of @code{gnu-build-system}, but with the
8169 following phases changed to some specific for Meson:
8174 The phase runs @code{meson} with the flags specified in
8175 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
8176 @code{debugoptimized} unless something else is specified in
8177 @code{#:build-type}.
8180 The phase runs @code{ninja} to build the package in parallel by default, but
8181 this can be changed with @code{#:parallel-build?}.
8184 The phase runs @code{ninja} with the target specified in @code{#:test-target},
8185 which is @code{"test"} by default.
8188 The phase runs @code{ninja install} and can not be changed.
8191 Apart from that, the build system also adds the following phases:
8196 This phase ensures that all binaries can find the libraries they need.
8197 It searches for required libraries in subdirectories of the package being
8198 built, and adds those to @code{RUNPATH} where needed. It also removes
8199 references to libraries left over from the build phase by
8200 @code{meson-for-build}, such as test dependencies, that aren't actually
8201 required for the program to run.
8203 @item glib-or-gtk-wrap
8204 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
8205 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
8207 @item glib-or-gtk-compile-schemas
8208 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
8209 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
8213 @defvr {Scheme Variable} linux-module-build-system
8214 @code{linux-module-build-system} allows building Linux kernel modules.
8216 @cindex build phases
8217 This build system is an extension of @code{gnu-build-system}, but with the
8218 following phases changed:
8223 This phase configures the environment so that the Linux kernel's Makefile
8224 can be used to build the external kernel module.
8227 This phase uses the Linux kernel's Makefile in order to build the external
8231 This phase uses the Linux kernel's Makefile in order to install the external
8235 It is possible and useful to specify the Linux kernel to use for building
8236 the module (in the @code{arguments} form of a package using the
8237 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
8240 @defvr {Scheme Variable} node-build-system
8241 This variable is exported by @code{(guix build-system node)}. It
8242 implements the build procedure used by @uref{https://nodejs.org,
8243 Node.js}, which implements an approximation of the @code{npm install}
8244 command, followed by an @code{npm test} command.
8246 Which Node.js package is used to interpret the @code{npm} commands can
8247 be specified with the @code{#:node} parameter which defaults to
8251 Lastly, for packages that do not need anything as sophisticated, a
8252 ``trivial'' build system is provided. It is trivial in the sense that
8253 it provides basically no support: it does not pull any implicit inputs,
8254 and does not have a notion of build phases.
8256 @defvr {Scheme Variable} trivial-build-system
8257 This variable is exported by @code{(guix build-system trivial)}.
8259 This build system requires a @code{#:builder} argument. This argument
8260 must be a Scheme expression that builds the package output(s)---as
8261 with @code{build-expression->derivation} (@pxref{Derivations,
8262 @code{build-expression->derivation}}).
8266 @section Build Phases
8268 @cindex build phases, for packages
8269 Almost all package build systems implement a notion @dfn{build phases}:
8270 a sequence of actions that the build system executes, when you build the
8271 package, leading to the installed byproducts in the store. A notable
8272 exception is the ``bare-bones'' @code{trivial-build-system}
8273 (@pxref{Build Systems}).
8275 As discussed in the previous section, those build systems provide a
8276 standard list of phases. For @code{gnu-build-system}, the main build
8277 phases are the following:
8281 Unpack the source tarball, and change the current directory to the
8282 extracted source tree. If the source is actually a directory, copy it
8283 to the build tree, and enter that directory.
8285 @item patch-source-shebangs
8286 Patch shebangs encountered in source files so they refer to the right
8287 store file names. For instance, this changes @code{#!/bin/sh} to
8288 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
8291 Run the @file{configure} script with a number of default options, such
8292 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
8293 by the @code{#:configure-flags} argument.
8296 Run @code{make} with the list of flags specified with
8297 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
8298 (the default), build with @code{make -j}.
8301 Run @code{make check}, or some other target specified with
8302 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
8303 @code{#:parallel-tests?} argument is true (the default), run @code{make
8307 Run @code{make install} with the flags listed in @code{#:make-flags}.
8309 @item patch-shebangs
8310 Patch shebangs on the installed executable files.
8313 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
8314 is false), copying them to the @code{debug} output when available
8315 (@pxref{Installing Debugging Files}).
8318 Other build systems have similar phases, with some variations. For
8319 example, @code{cmake-build-system} has same-named phases but its
8320 @code{configure} phases runs @code{cmake} instead of @code{./configure}.
8321 Others, such as @code{python-build-system}, have a wholly different list
8322 of standard phases. All this code runs on the @dfn{build side}: it is
8323 evaluated when you actually build the package, in a dedicated build
8324 process spawned by the build daemon (@pxref{Invoking guix-daemon}).
8326 Build phases are represented as association lists or ``alists''
8327 (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
8328 each key is a symbol for the name of the phase and the associated value
8329 is a procedure that accepts an arbitrary number of arguments. By
8330 convention, those procedures receive information about the build in the
8331 form of @dfn{keyword parameters}, which they can use or ignore.
8333 @vindex %standard-phases
8334 For example, here is how @code{(guix build gnu-build-system)} defines
8335 @code{%standard-phases}, the variable holding its alist of build
8336 phases@footnote{We present a simplified view of those build phases, but
8337 do take a look at @code{(guix build gnu-build-system)} to see all the
8341 ;; The build phases of 'gnu-build-system'.
8343 (define* (unpack #:key source #:allow-other-keys)
8344 ;; Extract the source tarball.
8345 (invoke "tar" "xvf" source))
8347 (define* (configure #:key outputs #:allow-other-keys)
8348 ;; Run the 'configure' script. Install to output "out".
8349 (let ((out (assoc-ref outputs "out")))
8350 (invoke "./configure"
8351 (string-append "--prefix=" out))))
8353 (define* (build #:allow-other-keys)
8357 (define* (check #:key (test-target "check") (tests? #true)
8359 ;; Run the test suite.
8361 (invoke "make" test-target)
8362 (display "test suite not run\n")))
8364 (define* (install #:allow-other-keys)
8365 ;; Install files to the prefix 'configure' specified.
8366 (invoke "make" "install"))
8368 (define %standard-phases
8369 ;; The list of standard phases (quite a few are omitted
8370 ;; for brevity). Each element is a symbol/procedure pair.
8371 (list (cons 'unpack unpack)
8372 (cons 'configure configure)
8375 (cons 'install install)))
8378 This shows how @code{%standard-phases} is defined as a list of
8379 symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
8380 Manual}). The first pair associates the @code{unpack} procedure with
8381 the @code{unpack} symbol---a name; the second pair defines the
8382 @code{configure} phase similarly, and so on. When building a package
8383 that uses @code{gnu-build-system} with its default list of phases, those
8384 phases are executed sequentially. You can see the name of each phase
8385 started and completed in the build log of packages that you build.
8387 Let's now look at the procedures themselves. Each one is defined with
8388 @code{define*}: @code{#:key} lists keyword parameters the procedure
8389 accepts, possibly with a default value, and @code{#:allow-other-keys}
8390 specifies that other keyword parameters are ignored (@pxref{Optional
8391 Arguments,,, guile, GNU Guile Reference Manual}).
8393 The @code{unpack} procedure honors the @code{source} parameter, which
8394 the build system uses to pass the file name of the source tarball (or
8395 version control checkout), and it ignores other parameters. The
8396 @code{configure} phase only cares about the @code{outputs} parameter, an
8397 alist mapping package output names to their store file name
8398 (@pxref{Packages with Multiple Outputs}). It extracts the file name of
8399 for @code{out}, the default output, and passes it to
8400 @command{./configure} as the installation prefix, meaning that
8401 @command{make install} will eventually copy all the files in that
8402 directory (@pxref{Configuration, configuration and makefile
8403 conventions,, standards, GNU Coding Standards}). @code{build} and
8404 @code{install} ignore all their arguments. @code{check} honors the
8405 @code{test-target} argument, which specifies the name of the Makefile
8406 target to run tests; it prints a message and skips tests when
8407 @code{tests?} is false.
8409 @cindex build phases, customizing
8410 The list of phases used for a particular package can be changed with the
8411 @code{#:phases} parameter of the build system. Changing the set of
8412 build phases boils down to building a new alist of phases based on the
8413 @code{%standard-phases} alist described above. This can be done with
8414 standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
8415 Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
8416 more convenient to do so with @code{modify-phases} (@pxref{Build
8417 Utilities, @code{modify-phases}}).
8419 Here is an example of a package definition that removes the
8420 @code{configure} phase of @code{%standard-phases} and inserts a new
8421 phase before the @code{build} phase, called
8422 @code{set-prefix-in-makefile}:
8425 (define-public example
8428 ;; other fields omitted
8429 (build-system gnu-build-system)
8431 '(#:phases (modify-phases %standard-phases
8433 (add-before 'build 'set-prefix-in-makefile
8434 (lambda* (#:key outputs #:allow-other-keys)
8435 ;; Modify the makefile so that its
8436 ;; 'PREFIX' variable points to "out".
8437 (let ((out (assoc-ref outputs "out")))
8438 (substitute* "Makefile"
8440 (string-append "PREFIX = "
8445 The new phase that is inserted is written as an anonymous procedure,
8446 introduced with @code{lambda*}; it honors the @code{outputs} parameter
8447 we have seen before. @xref{Build Utilities}, for more about the helpers
8448 used by this phase, and for more examples of @code{modify-phases}.
8450 @cindex code staging
8451 @cindex staging, of code
8452 Keep in mind that build phases are code evaluated at the time the
8453 package is actually built. This explains why the whole
8454 @code{modify-phases} expression above is quoted (it comes after the
8455 @code{'} or apostrophe): it is @dfn{staged} for later execution.
8456 @xref{G-Expressions}, for an explanation of code staging and the
8457 @dfn{code strata} involved.
8459 @node Build Utilities
8460 @section Build Utilities
8462 As soon as you start writing non-trivial package definitions
8463 (@pxref{Defining Packages}) or other build actions
8464 (@pxref{G-Expressions}), you will likely start looking for helpers for
8465 ``shell-like'' actions---creating directories, copying and deleting
8466 files recursively, manipulating build phases, and so on. The
8467 @code{(guix build utils)} module provides such utility procedures.
8469 Most build systems load @code{(guix build utils)} (@pxref{Build
8470 Systems}). Thus, when writing custom build phases for your package
8471 definitions, you can usually assume those procedures are in scope.
8473 When writing G-expressions, you can import @code{(guix build utils)} on
8474 the ``build side'' using @code{with-imported-modules} and then put it in
8475 scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
8476 guile, GNU Guile Reference Manual}):
8479 (with-imported-modules '((guix build utils)) ;import it
8480 (computed-file "empty-tree"
8483 (use-modules (guix build utils))
8485 ;; Happily use its 'mkdir-p' procedure.
8486 (mkdir-p (string-append #$output "/a/b/c")))))
8489 The remainder of this section is the reference for most of the utility
8490 procedures provided by @code{(guix build utils)}.
8492 @c TODO Document what's missing.
8494 @subsection Dealing with Store File Names
8496 This section documents procedures that deal with store file names.
8498 @deffn {Scheme Procedure} %store-directory
8499 Return the directory name of the store.
8502 @deffn {Scheme Procedure} store-file-name? @var{file}
8503 Return true if @var{file} is in the store.
8506 @deffn {Scheme Procedure} strip-store-file-name @var{file}
8507 Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
8508 The result is typically a @code{"@var{package}-@var{version}"} string.
8511 @deffn {Scheme Procedure} package-name->name+version @var{name}
8512 Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
8513 values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
8514 unavailable, @var{name} and @code{#f} are returned. The first hyphen
8515 followed by a digit is considered to introduce the version part.
8518 @subsection File Types
8520 The procedures below deal with files and file types.
8522 @deffn {Scheme Procedure} directory-exists? @var{dir}
8523 Return @code{#t} if @var{dir} exists and is a directory.
8526 @deffn {Scheme Procedure} executable-file? @var{file}
8527 Return @code{#t} if @var{file} exists and is executable.
8530 @deffn {Scheme Procedure} symbolic-link? @var{file}
8531 Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
8534 @deffn {Scheme Procedure} elf-file? @var{file}
8535 @deffnx {Scheme Procedure} ar-file? @var{file}
8536 @deffnx {Scheme Procedure} gzip-file? @var{file}
8537 Return @code{#t} if @var{file} is, respectively, an ELF file, an
8538 @code{ar} archive (such as a @file{.a} static library), or a gzip file.
8541 @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
8542 If @var{file} is a gzip file, reset its embedded timestamp (as with
8543 @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
8544 When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
8547 @subsection File Manipulation
8549 The following procedures and macros help create, modify, and delete
8550 files. They provide functionality comparable to common shell utilities
8551 such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
8552 @command{sed}. They complement Guile's extensive, but low-level, file
8553 system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
8555 @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
8556 Run @var{body} with @var{directory} as the process's current directory.
8558 Essentially, this macro changes the current directory to @var{directory}
8559 before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
8560 guile, GNU Guile Reference Manual}). It changes back to the initial
8561 directory when the dynamic extent of @var{body} is left, be it @i{via}
8562 normal procedure return or @i{via} a non-local exit such as an
8566 @deffn {Scheme Procedure} mkdir-p @var{dir}
8567 Create directory @var{dir} and all its ancestors.
8570 @deffn {Scheme Procedure} install-file @var{file} @var{directory}
8571 Create @var{directory} if it does not exist and copy @var{file} in there
8572 under the same name.
8575 @deffn {Scheme Procedure} make-file-writable @var{file}
8576 Make @var{file} writable for its owner.
8579 @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
8580 [#:log (current-output-port)] [#:follow-symlinks? #f] [#:keep-mtime? #f]
8581 Copy @var{source} directory to @var{destination}. Follow symlinks if
8582 @var{follow-symlinks?} is true; otherwise, just preserve them. When
8583 @var{keep-mtime?} is true, keep the modification time of the files in
8584 @var{source} on those of @var{destination}. Write verbose output to the
8588 @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
8589 [#:follow-mounts? #f]
8590 Delete @var{dir} recursively, like @command{rm -rf}, without following
8591 symlinks. Don't follow mount points either, unless @var{follow-mounts?}
8592 is true. Report but ignore errors.
8595 @deffn {Scheme Syntax} substitute* @var{file} @
8596 ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
8597 Substitute @var{regexp} in @var{file} by the string returned by
8598 @var{body}. @var{body} is evaluated with each @var{match-var} bound to
8599 the corresponding positional regexp sub-expression. For example:
8605 (("foo([a-z]+)bar(.*)$" all letters end)
8606 (string-append "baz" letter end)))
8609 Here, anytime a line of @var{file} contains @code{hello}, it is replaced
8610 by @code{good morning}. Anytime a line of @var{file} matches the second
8611 regexp, @code{all} is bound to the complete match, @code{letters} is bound
8612 to the first sub-expression, and @code{end} is bound to the last one.
8614 When one of the @var{match-var} is @code{_}, no variable is bound to the
8615 corresponding match substring.
8617 Alternatively, @var{file} may be a list of file names, in which case
8618 they are all subject to the substitutions.
8620 Be careful about using @code{$} to match the end of a line; by itself it
8621 won't match the terminating newline of a line.
8624 @subsection File Search
8626 @cindex file, searching
8627 This section documents procedures to search and filter files.
8629 @deffn {Scheme Procedure} file-name-predicate @var{regexp}
8630 Return a predicate that returns true when passed a file name whose base
8631 name matches @var{regexp}.
8634 @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
8635 [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
8636 Return the lexicographically sorted list of files under @var{dir} for
8637 which @var{pred} returns true. @var{pred} is passed two arguments: the
8638 absolute file name, and its stat buffer; the default predicate always
8639 returns true. @var{pred} can also be a regular expression, in which
8640 case it is equivalent to @code{(file-name-predicate @var{pred})}.
8641 @var{stat} is used to obtain file information; using @code{lstat} means
8642 that symlinks are not followed. If @var{directories?} is true, then
8643 directories will also be included. If @var{fail-on-error?} is true,
8644 raise an exception upon error.
8647 Here are a few examples where we assume that the current directory is
8648 the root of the Guix source tree:
8651 ;; List all the regular files in the current directory.
8653 @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
8655 ;; List all the .scm files under gnu/services.
8656 (find-files "gnu/services" "\\.scm$")
8657 @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
8659 ;; List ar files in the current directory.
8660 (find-files "." (lambda (file stat) (ar-file? file)))
8661 @result{} ("./libformat.a" "./libstore.a" @dots{})
8664 @deffn {Scheme Procedure} which @var{program}
8665 Return the complete file name for @var{program} as found in
8666 @code{$PATH}, or @code{#f} if @var{program} could not be found.
8669 @subsection Build Phases
8671 @cindex build phases
8672 The @code{(guix build utils)} also contains tools to manipulate build
8673 phases as used by build systems (@pxref{Build Systems}). Build phases
8674 are represented as association lists or ``alists'' (@pxref{Association
8675 Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
8676 naming the phase and the associated value is a procedure (@pxref{Build
8679 Guile core and the @code{(srfi srfi-1)} module both provide tools to
8680 manipulate alists. The @code{(guix build utils)} module complements
8681 those with tools written with build phases in mind.
8683 @cindex build phases, modifying
8684 @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
8685 Modify @var{phases} sequentially as per each @var{clause}, which may
8686 have one of the following forms:
8689 (delete @var{old-phase-name})
8690 (replace @var{old-phase-name} @var{new-phase})
8691 (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
8692 (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
8695 Where every @var{phase-name} above is an expression evaluating to a
8696 symbol, and @var{new-phase} an expression evaluating to a procedure.
8699 The example below is taken from the definition of the @code{grep}
8700 package. It adds a phase to run after the @code{install} phase, called
8701 @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
8702 is for anonymous procedures) that takes a @code{#:outputs} keyword
8703 argument and ignores extra keyword arguments (@pxref{Optional
8704 Arguments,,, guile, GNU Guile Reference Manual}, for more on
8705 @code{lambda*} and optional and keyword arguments.) The phase uses
8706 @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
8707 scripts so that they refer to @code{grep} by its absolute file name:
8710 (modify-phases %standard-phases
8711 (add-after 'install 'fix-egrep-and-fgrep
8712 ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
8713 ;; absolute file name instead of searching for it in $PATH.
8714 (lambda* (#:key outputs #:allow-other-keys)
8715 (let* ((out (assoc-ref outputs "out"))
8716 (bin (string-append out "/bin")))
8717 (substitute* (list (string-append bin "/egrep")
8718 (string-append bin "/fgrep"))
8720 (string-append "exec " bin "/grep")))
8724 In the example below, phases are modified in two ways: the standard
8725 @code{configure} phase is deleted, presumably because the package does
8726 not have a @file{configure} script or anything similar, and the default
8727 @code{install} phase is replaced by one that manually copies the
8728 executable files to be installed:
8731 (modify-phases %standard-phases
8732 (delete 'configure) ;no 'configure' script
8734 (lambda* (#:key outputs #:allow-other-keys)
8735 ;; The package's Makefile doesn't provide an "install"
8736 ;; rule so do it by ourselves.
8737 (let ((bin (string-append (assoc-ref outputs "out")
8739 (install-file "footswitch" bin)
8740 (install-file "scythe" bin)
8744 @c TODO: Add more examples.
8753 Conceptually, the @dfn{store} is the place where derivations that have
8754 been built successfully are stored---by default, @file{/gnu/store}.
8755 Sub-directories in the store are referred to as @dfn{store items} or
8756 sometimes @dfn{store paths}. The store has an associated database that
8757 contains information such as the store paths referred to by each store
8758 path, and the list of @emph{valid} store items---results of successful
8759 builds. This database resides in @file{@var{localstatedir}/guix/db},
8760 where @var{localstatedir} is the state directory specified @i{via}
8761 @option{--localstatedir} at configure time, usually @file{/var}.
8763 The store is @emph{always} accessed by the daemon on behalf of its clients
8764 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
8765 connect to the daemon over a Unix-domain socket, send requests to it,
8766 and read the result---these are remote procedure calls, or RPCs.
8769 Users must @emph{never} modify files under @file{/gnu/store} directly.
8770 This would lead to inconsistencies and break the immutability
8771 assumptions of Guix's functional model (@pxref{Introduction}).
8773 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
8774 how to check the integrity of the store and attempt recovery from
8775 accidental modifications.
8778 The @code{(guix store)} module provides procedures to connect to the
8779 daemon, and to perform RPCs. These are described below. By default,
8780 @code{open-connection}, and thus all the @command{guix} commands,
8781 connect to the local daemon or to the URI specified by the
8782 @env{GUIX_DAEMON_SOCKET} environment variable.
8784 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
8785 When set, the value of this variable should be a file name or a URI
8786 designating the daemon endpoint. When it is a file name, it denotes a
8787 Unix-domain socket to connect to. In addition to file names, the
8788 supported URI schemes are:
8793 These are for Unix-domain sockets.
8794 @code{file:///var/guix/daemon-socket/socket} is equivalent to
8795 @file{/var/guix/daemon-socket/socket}.
8798 @cindex daemon, remote access
8799 @cindex remote access to the daemon
8800 @cindex daemon, cluster setup
8801 @cindex clusters, daemon setup
8802 These URIs denote connections over TCP/IP, without encryption nor
8803 authentication of the remote host. The URI must specify the host name
8804 and optionally a port number (by default port 44146 is used):
8807 guix://master.guix.example.org:1234
8810 This setup is suitable on local networks, such as clusters, where only
8811 trusted nodes may connect to the build daemon at
8812 @code{master.guix.example.org}.
8814 The @option{--listen} option of @command{guix-daemon} can be used to
8815 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
8816 @option{--listen}}).
8819 @cindex SSH access to build daemons
8820 These URIs allow you to connect to a remote daemon over SSH@. This
8821 feature requires Guile-SSH (@pxref{Requirements}) and a working
8822 @command{guile} binary in @env{PATH} on the destination machine. It
8823 supports public key and GSSAPI authentication. A typical URL might look
8827 ssh://charlie@@guix.example.org:22
8830 As for @command{guix copy}, the usual OpenSSH client configuration files
8831 are honored (@pxref{Invoking guix copy}).
8834 Additional URI schemes may be supported in the future.
8836 @c XXX: Remove this note when the protocol incurs fewer round trips
8837 @c and when (guix derivations) no longer relies on file system access.
8839 The ability to connect to remote build daemons is considered
8840 experimental as of @value{VERSION}. Please get in touch with us to
8841 share any problems or suggestions you may have (@pxref{Contributing}).
8845 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
8846 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
8847 @var{reserve-space?} is true, instruct it to reserve a little bit of
8848 extra space on the file system so that the garbage collector can still
8849 operate should the disk become full. Return a server object.
8851 @var{file} defaults to @code{%default-socket-path}, which is the normal
8852 location given the options that were passed to @command{configure}.
8855 @deffn {Scheme Procedure} close-connection @var{server}
8856 Close the connection to @var{server}.
8859 @defvr {Scheme Variable} current-build-output-port
8860 This variable is bound to a SRFI-39 parameter, which refers to the port
8861 where build and error logs sent by the daemon should be written.
8864 Procedures that make RPCs all take a server object as their first
8867 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
8868 @cindex invalid store items
8869 Return @code{#t} when @var{path} designates a valid store item and
8870 @code{#f} otherwise (an invalid item may exist on disk but still be
8871 invalid, for instance because it is the result of an aborted or failed
8874 A @code{&store-protocol-error} condition is raised if @var{path} is not
8875 prefixed by the store directory (@file{/gnu/store}).
8878 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
8879 Add @var{text} under file @var{name} in the store, and return its store
8880 path. @var{references} is the list of store paths referred to by the
8881 resulting store path.
8884 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
8886 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
8887 file names, or derivation/output pairs, using the specified
8888 @var{mode}---@code{(build-mode normal)} by default.
8891 Note that the @code{(guix monads)} module provides a monad as well as
8892 monadic versions of the above procedures, with the goal of making it
8893 more convenient to work with code that accesses the store (@pxref{The
8897 @i{This section is currently incomplete.}
8900 @section Derivations
8903 Low-level build actions and the environment in which they are performed
8904 are represented by @dfn{derivations}. A derivation contains the
8905 following pieces of information:
8909 The outputs of the derivation---derivations produce at least one file or
8910 directory in the store, but may produce more.
8913 @cindex build-time dependencies
8914 @cindex dependencies, build-time
8915 The inputs of the derivations---i.e., its build-time dependencies---which may
8916 be other derivations or plain files in the store (patches, build scripts,
8920 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
8923 The file name of a build script in the store, along with the arguments
8927 A list of environment variables to be defined.
8931 @cindex derivation path
8932 Derivations allow clients of the daemon to communicate build actions to
8933 the store. They exist in two forms: as an in-memory representation,
8934 both on the client- and daemon-side, and as files in the store whose
8935 name end in @file{.drv}---these files are referred to as @dfn{derivation
8936 paths}. Derivations paths can be passed to the @code{build-derivations}
8937 procedure to perform the build actions they prescribe (@pxref{The
8940 @cindex fixed-output derivations
8941 Operations such as file downloads and version-control checkouts for
8942 which the expected content hash is known in advance are modeled as
8943 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
8944 of a fixed-output derivation are independent of its inputs---e.g., a
8945 source code download produces the same result regardless of the download
8946 method and tools being used.
8949 @cindex run-time dependencies
8950 @cindex dependencies, run-time
8951 The outputs of derivations---i.e., the build results---have a set of
8952 @dfn{references}, as reported by the @code{references} RPC or the
8953 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
8954 are the set of run-time dependencies of the build results. References are a
8955 subset of the inputs of the derivation; this subset is automatically computed
8956 by the build daemon by scanning all the files in the outputs.
8958 The @code{(guix derivations)} module provides a representation of
8959 derivations as Scheme objects, along with procedures to create and
8960 otherwise manipulate derivations. The lowest-level primitive to create
8961 a derivation is the @code{derivation} procedure:
8963 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
8964 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
8965 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
8966 [#:system (%current-system)] [#:references-graphs #f] @
8967 [#:allowed-references #f] [#:disallowed-references #f] @
8968 [#:leaked-env-vars #f] [#:local-build? #f] @
8969 [#:substitutable? #t] [#:properties '()]
8970 Build a derivation with the given arguments, and return the resulting
8971 @code{<derivation>} object.
8973 When @var{hash} and @var{hash-algo} are given, a
8974 @dfn{fixed-output derivation} is created---i.e., one whose result is
8975 known in advance, such as a file download. If, in addition,
8976 @var{recursive?} is true, then that fixed output may be an executable
8977 file or a directory and @var{hash} must be the hash of an archive
8978 containing this output.
8980 When @var{references-graphs} is true, it must be a list of file
8981 name/store path pairs. In that case, the reference graph of each store
8982 path is exported in the build environment in the corresponding file, in
8983 a simple text format.
8985 When @var{allowed-references} is true, it must be a list of store items
8986 or outputs that the derivation's output may refer to. Likewise,
8987 @var{disallowed-references}, if true, must be a list of things the
8988 outputs may @emph{not} refer to.
8990 When @var{leaked-env-vars} is true, it must be a list of strings
8991 denoting environment variables that are allowed to ``leak'' from the
8992 daemon's environment to the build environment. This is only applicable
8993 to fixed-output derivations---i.e., when @var{hash} is true. The main
8994 use is to allow variables such as @code{http_proxy} to be passed to
8995 derivations that download files.
8997 When @var{local-build?} is true, declare that the derivation is not a
8998 good candidate for offloading and should rather be built locally
8999 (@pxref{Daemon Offload Setup}). This is the case for small derivations
9000 where the costs of data transfers would outweigh the benefits.
9002 When @var{substitutable?} is false, declare that substitutes of the
9003 derivation's output should not be used (@pxref{Substitutes}). This is
9004 useful, for instance, when building packages that capture details of the
9005 host CPU instruction set.
9007 @var{properties} must be an association list describing ``properties'' of the
9008 derivation. It is kept as-is, uninterpreted, in the derivation.
9012 Here's an example with a shell script as its builder, assuming
9013 @var{store} is an open connection to the daemon, and @var{bash} points
9014 to a Bash executable in the store:
9017 (use-modules (guix utils)
9021 (let ((builder ; add the Bash script to the store
9022 (add-text-to-store store "my-builder.sh"
9023 "echo hello world > $out\n" '())))
9024 (derivation store "foo"
9025 bash `("-e" ,builder)
9026 #:inputs `((,bash) (,builder))
9027 #:env-vars '(("HOME" . "/homeless"))))
9028 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
9031 As can be guessed, this primitive is cumbersome to use directly. A
9032 better approach is to write build scripts in Scheme, of course! The
9033 best course of action for that is to write the build code as a
9034 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
9035 information, @pxref{G-Expressions}.
9037 Once upon a time, @code{gexp->derivation} did not exist and constructing
9038 derivations with build code written in Scheme was achieved with
9039 @code{build-expression->derivation}, documented below. This procedure
9040 is now deprecated in favor of the much nicer @code{gexp->derivation}.
9042 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
9043 @var{name} @var{exp} @
9044 [#:system (%current-system)] [#:inputs '()] @
9045 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
9046 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
9047 [#:references-graphs #f] [#:allowed-references #f] @
9048 [#:disallowed-references #f] @
9049 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
9050 Return a derivation that executes Scheme expression @var{exp} as a
9051 builder for derivation @var{name}. @var{inputs} must be a list of
9052 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
9053 @code{"out"} is assumed. @var{modules} is a list of names of Guile
9054 modules from the current search path to be copied in the store,
9055 compiled, and made available in the load path during the execution of
9056 @var{exp}---e.g., @code{((guix build utils) (guix build
9057 gnu-build-system))}.
9059 @var{exp} is evaluated in an environment where @code{%outputs} is bound
9060 to a list of output/path pairs, and where @code{%build-inputs} is bound
9061 to a list of string/output-path pairs made from @var{inputs}.
9062 Optionally, @var{env-vars} is a list of string pairs specifying the name
9063 and value of environment variables visible to the builder. The builder
9064 terminates by passing the result of @var{exp} to @code{exit}; thus, when
9065 @var{exp} returns @code{#f}, the build is considered to have failed.
9067 @var{exp} is built using @var{guile-for-build} (a derivation). When
9068 @var{guile-for-build} is omitted or is @code{#f}, the value of the
9069 @code{%guile-for-build} fluid is used instead.
9071 See the @code{derivation} procedure for the meaning of
9072 @var{references-graphs}, @var{allowed-references},
9073 @var{disallowed-references}, @var{local-build?}, and
9074 @var{substitutable?}.
9078 Here's an example of a single-output derivation that creates a directory
9079 containing one file:
9082 (let ((builder '(let ((out (assoc-ref %outputs "out")))
9083 (mkdir out) ; create /gnu/store/@dots{}-goo
9084 (call-with-output-file (string-append out "/test")
9086 (display '(hello guix) p))))))
9087 (build-expression->derivation store "goo" builder))
9089 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
9093 @node The Store Monad
9094 @section The Store Monad
9098 The procedures that operate on the store described in the previous
9099 sections all take an open connection to the build daemon as their first
9100 argument. Although the underlying model is functional, they either have
9101 side effects or depend on the current state of the store.
9103 The former is inconvenient: the connection to the build daemon has to be
9104 carried around in all those functions, making it impossible to compose
9105 functions that do not take that parameter with functions that do. The
9106 latter can be problematic: since store operations have side effects
9107 and/or depend on external state, they have to be properly sequenced.
9109 @cindex monadic values
9110 @cindex monadic functions
9111 This is where the @code{(guix monads)} module comes in. This module
9112 provides a framework for working with @dfn{monads}, and a particularly
9113 useful monad for our uses, the @dfn{store monad}. Monads are a
9114 construct that allows two things: associating ``context'' with values
9115 (in our case, the context is the store), and building sequences of
9116 computations (here computations include accesses to the store). Values
9117 in a monad---values that carry this additional context---are called
9118 @dfn{monadic values}; procedures that return such values are called
9119 @dfn{monadic procedures}.
9121 Consider this ``normal'' procedure:
9124 (define (sh-symlink store)
9125 ;; Return a derivation that symlinks the 'bash' executable.
9126 (let* ((drv (package-derivation store bash))
9127 (out (derivation->output-path drv))
9128 (sh (string-append out "/bin/bash")))
9129 (build-expression->derivation store "sh"
9130 `(symlink ,sh %output))))
9133 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
9134 as a monadic function:
9137 (define (sh-symlink)
9138 ;; Same, but return a monadic value.
9139 (mlet %store-monad ((drv (package->derivation bash)))
9140 (gexp->derivation "sh"
9141 #~(symlink (string-append #$drv "/bin/bash")
9145 There are several things to note in the second version: the @code{store}
9146 parameter is now implicit and is ``threaded'' in the calls to the
9147 @code{package->derivation} and @code{gexp->derivation} monadic
9148 procedures, and the monadic value returned by @code{package->derivation}
9149 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
9151 As it turns out, the call to @code{package->derivation} can even be
9152 omitted since it will take place implicitly, as we will see later
9153 (@pxref{G-Expressions}):
9156 (define (sh-symlink)
9157 (gexp->derivation "sh"
9158 #~(symlink (string-append #$bash "/bin/bash")
9163 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
9164 @c for the funny quote.
9165 Calling the monadic @code{sh-symlink} has no effect. As someone once
9166 said, ``you exit a monad like you exit a building on fire: by running''.
9167 So, to exit the monad and get the desired effect, one must use
9168 @code{run-with-store}:
9171 (run-with-store (open-connection) (sh-symlink))
9172 @result{} /gnu/store/...-sh-symlink
9175 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
9176 new ``meta-commands'' to make it easier to deal with monadic procedures:
9177 @code{run-in-store}, and @code{enter-store-monad}. The former is used
9178 to ``run'' a single monadic value through the store:
9181 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
9182 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
9185 The latter enters a recursive REPL, where all the return values are
9186 automatically run through the store:
9189 scheme@@(guile-user)> ,enter-store-monad
9190 store-monad@@(guile-user) [1]> (package->derivation hello)
9191 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
9192 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
9193 $3 = "/gnu/store/@dots{}-foo"
9194 store-monad@@(guile-user) [1]> ,q
9195 scheme@@(guile-user)>
9199 Note that non-monadic values cannot be returned in the
9200 @code{store-monad} REPL.
9202 The main syntactic forms to deal with monads in general are provided by
9203 the @code{(guix monads)} module and are described below.
9205 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
9206 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
9210 @deffn {Scheme Syntax} return @var{val}
9211 Return a monadic value that encapsulates @var{val}.
9214 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
9215 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
9216 procedures @var{mproc}@dots{}@footnote{This operation is commonly
9217 referred to as ``bind'', but that name denotes an unrelated procedure in
9218 Guile. Thus we use this somewhat cryptic symbol inherited from the
9219 Haskell language.}. There can be one @var{mproc} or several of them, as
9224 (with-monad %state-monad
9226 (lambda (x) (return (+ 1 x)))
9227 (lambda (x) (return (* 2 x)))))
9231 @result{} some-state
9235 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
9237 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
9239 Bind the variables @var{var} to the monadic values @var{mval} in
9240 @var{body}, which is a sequence of expressions. As with the bind
9241 operator, this can be thought of as ``unpacking'' the raw, non-monadic
9242 value ``contained'' in @var{mval} and making @var{var} refer to that
9243 raw, non-monadic value within the scope of the @var{body}. The form
9244 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
9245 @var{val}, as per @code{let}. The binding operations occur in sequence
9246 from left to right. The last expression of @var{body} must be a monadic
9247 expression, and its result will become the result of the @code{mlet} or
9248 @code{mlet*} when run in the @var{monad}.
9250 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
9251 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
9254 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
9255 Bind @var{mexp} and the following monadic expressions in sequence,
9256 returning the result of the last expression. Every expression in the
9257 sequence must be a monadic expression.
9259 This is akin to @code{mlet}, except that the return values of the
9260 monadic expressions are ignored. In that sense, it is analogous to
9261 @code{begin}, but applied to monadic expressions.
9264 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
9265 When @var{condition} is true, evaluate the sequence of monadic
9266 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
9267 @var{condition} is false, return @code{*unspecified*} in the current
9268 monad. Every expression in the sequence must be a monadic expression.
9271 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
9272 When @var{condition} is false, evaluate the sequence of monadic
9273 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
9274 @var{condition} is true, return @code{*unspecified*} in the current
9275 monad. Every expression in the sequence must be a monadic expression.
9279 The @code{(guix monads)} module provides the @dfn{state monad}, which
9280 allows an additional value---the state---to be @emph{threaded} through
9281 monadic procedure calls.
9283 @defvr {Scheme Variable} %state-monad
9284 The state monad. Procedures in the state monad can access and change
9285 the state that is threaded.
9287 Consider the example below. The @code{square} procedure returns a value
9288 in the state monad. It returns the square of its argument, but also
9289 increments the current state value:
9293 (mlet %state-monad ((count (current-state)))
9294 (mbegin %state-monad
9295 (set-current-state (+ 1 count))
9298 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
9303 When ``run'' through @code{%state-monad}, we obtain that additional state
9304 value, which is the number of @code{square} calls.
9307 @deffn {Monadic Procedure} current-state
9308 Return the current state as a monadic value.
9311 @deffn {Monadic Procedure} set-current-state @var{value}
9312 Set the current state to @var{value} and return the previous state as a
9316 @deffn {Monadic Procedure} state-push @var{value}
9317 Push @var{value} to the current state, which is assumed to be a list,
9318 and return the previous state as a monadic value.
9321 @deffn {Monadic Procedure} state-pop
9322 Pop a value from the current state and return it as a monadic value.
9323 The state is assumed to be a list.
9326 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
9327 Run monadic value @var{mval} starting with @var{state} as the initial
9328 state. Return two values: the resulting value, and the resulting state.
9331 The main interface to the store monad, provided by the @code{(guix
9332 store)} module, is as follows.
9334 @defvr {Scheme Variable} %store-monad
9335 The store monad---an alias for @code{%state-monad}.
9337 Values in the store monad encapsulate accesses to the store. When its
9338 effect is needed, a value of the store monad must be ``evaluated'' by
9339 passing it to the @code{run-with-store} procedure (see below).
9342 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
9343 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
9344 open store connection.
9347 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
9348 Return as a monadic value the absolute file name in the store of the file
9349 containing @var{text}, a string. @var{references} is a list of store items that the
9350 resulting text file refers to; it defaults to the empty list.
9353 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
9354 Return as a monadic value the absolute file name in the store of the file
9355 containing @var{data}, a bytevector. @var{references} is a list of store
9356 items that the resulting binary file refers to; it defaults to the empty list.
9359 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
9360 [#:recursive? #t] [#:select? (const #t)]
9361 Return the name of @var{file} once interned in the store. Use
9362 @var{name} as its store name, or the basename of @var{file} if
9363 @var{name} is omitted.
9365 When @var{recursive?} is true, the contents of @var{file} are added
9366 recursively; if @var{file} designates a flat file and @var{recursive?}
9367 is true, its contents are added, and its permission bits are kept.
9369 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
9370 @var{stat})} for each directory entry, where @var{file} is the entry's
9371 absolute file name and @var{stat} is the result of @code{lstat}; exclude
9372 entries for which @var{select?} does not return true.
9374 The example below adds a file to the store, under two different names:
9377 (run-with-store (open-connection)
9378 (mlet %store-monad ((a (interned-file "README"))
9379 (b (interned-file "README" "LEGU-MIN")))
9380 (return (list a b))))
9382 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
9387 The @code{(guix packages)} module exports the following package-related
9390 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
9391 [#:system (%current-system)] [#:target #f] @
9394 value in the absolute file name of @var{file} within the @var{output}
9395 directory of @var{package}. When @var{file} is omitted, return the name
9396 of the @var{output} directory of @var{package}. When @var{target} is
9397 true, use it as a cross-compilation target triplet.
9399 Note that this procedure does @emph{not} build @var{package}. Thus, the
9400 result might or might not designate an existing file. We recommend not
9401 using this procedure unless you know what you are doing.
9404 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
9405 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
9406 @var{target} [@var{system}]
9407 Monadic version of @code{package-derivation} and
9408 @code{package-cross-derivation} (@pxref{Defining Packages}).
9413 @section G-Expressions
9415 @cindex G-expression
9416 @cindex build code quoting
9417 So we have ``derivations'', which represent a sequence of build actions
9418 to be performed to produce an item in the store (@pxref{Derivations}).
9419 These build actions are performed when asking the daemon to actually
9420 build the derivations; they are run by the daemon in a container
9421 (@pxref{Invoking guix-daemon}).
9423 @cindex code staging
9424 @cindex staging, of code
9425 @cindex strata of code
9426 It should come as no surprise that we like to write these build actions
9427 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
9428 code@footnote{The term @dfn{stratum} in this context was coined by
9429 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
9430 Kiselyov, who has written insightful
9431 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
9432 on this topic}, refers to this kind of code generation as
9433 @dfn{staging}.}: the ``host code''---code that defines packages, talks
9434 to the daemon, etc.---and the ``build code''---code that actually
9435 performs build actions, such as making directories, invoking
9436 @command{make}, and so on (@pxref{Build Phases}).
9438 To describe a derivation and its build actions, one typically needs to
9439 embed build code inside host code. It boils down to manipulating build
9440 code as data, and the homoiconicity of Scheme---code has a direct
9441 representation as data---comes in handy for that. But we need more than
9442 the normal @code{quasiquote} mechanism in Scheme to construct build
9445 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
9446 S-expressions adapted to build expressions. G-expressions, or
9447 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
9448 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
9449 @code{#$}, and @code{#$@@}), which are comparable to
9450 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
9451 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
9452 GNU Guile Reference Manual}). However, there are major differences:
9456 Gexps are meant to be written to a file and run or manipulated by other
9460 When a high-level object such as a package or derivation is unquoted
9461 inside a gexp, the result is as if its output file name had been
9465 Gexps carry information about the packages or derivations they refer to,
9466 and these dependencies are automatically added as inputs to the build
9467 processes that use them.
9470 @cindex lowering, of high-level objects in gexps
9471 This mechanism is not limited to package and derivation
9472 objects: @dfn{compilers} able to ``lower'' other high-level objects to
9473 derivations or files in the store can be defined,
9474 such that these objects can also be inserted
9475 into gexps. For example, a useful type of high-level objects that can be
9476 inserted in a gexp is ``file-like objects'', which make it easy to
9477 add files to the store and to refer to them in
9478 derivations and such (see @code{local-file} and @code{plain-file}
9481 To illustrate the idea, here is an example of a gexp:
9488 (symlink (string-append #$coreutils "/bin/ls")
9492 This gexp can be passed to @code{gexp->derivation}; we obtain a
9493 derivation that builds a directory containing exactly one symlink to
9494 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
9497 (gexp->derivation "the-thing" build-exp)
9500 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
9501 substituted to the reference to the @var{coreutils} package in the
9502 actual build code, and @var{coreutils} is automatically made an input to
9503 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
9504 output)}) is replaced by a string containing the directory name of the
9505 output of the derivation.
9507 @cindex cross compilation
9508 In a cross-compilation context, it is useful to distinguish between
9509 references to the @emph{native} build of a package---that can run on the
9510 host---versus references to cross builds of a package. To that end, the
9511 @code{#+} plays the same role as @code{#$}, but is a reference to a
9512 native package build:
9515 (gexp->derivation "vi"
9518 (mkdir (string-append #$output "/bin"))
9519 (system* (string-append #+coreutils "/bin/ln")
9521 (string-append #$emacs "/bin/emacs")
9522 (string-append #$output "/bin/vi")))
9523 #:target "aarch64-linux-gnu")
9527 In the example above, the native build of @var{coreutils} is used, so
9528 that @command{ln} can actually run on the host; but then the
9529 cross-compiled build of @var{emacs} is referenced.
9531 @cindex imported modules, for gexps
9532 @findex with-imported-modules
9533 Another gexp feature is @dfn{imported modules}: sometimes you want to be
9534 able to use certain Guile modules from the ``host environment'' in the
9535 gexp, so those modules should be imported in the ``build environment''.
9536 The @code{with-imported-modules} form allows you to express that:
9539 (let ((build (with-imported-modules '((guix build utils))
9541 (use-modules (guix build utils))
9542 (mkdir-p (string-append #$output "/bin"))))))
9543 (gexp->derivation "empty-dir"
9546 (display "success!\n")
9551 In this example, the @code{(guix build utils)} module is automatically
9552 pulled into the isolated build environment of our gexp, such that
9553 @code{(use-modules (guix build utils))} works as expected.
9555 @cindex module closure
9556 @findex source-module-closure
9557 Usually you want the @emph{closure} of the module to be imported---i.e.,
9558 the module itself and all the modules it depends on---rather than just
9559 the module; failing to do that, attempts to use the module will fail
9560 because of missing dependent modules. The @code{source-module-closure}
9561 procedure computes the closure of a module by looking at its source file
9562 headers, which comes in handy in this case:
9565 (use-modules (guix modules)) ;for 'source-module-closure'
9567 (with-imported-modules (source-module-closure
9568 '((guix build utils)
9570 (gexp->derivation "something-with-vms"
9572 (use-modules (guix build utils)
9577 @cindex extensions, for gexps
9578 @findex with-extensions
9579 In the same vein, sometimes you want to import not just pure-Scheme
9580 modules, but also ``extensions'' such as Guile bindings to C libraries
9581 or other ``full-blown'' packages. Say you need the @code{guile-json}
9582 package available on the build side, here's how you would do it:
9585 (use-modules (gnu packages guile)) ;for 'guile-json'
9587 (with-extensions (list guile-json)
9588 (gexp->derivation "something-with-json"
9590 (use-modules (json))
9594 The syntactic form to construct gexps is summarized below.
9596 @deffn {Scheme Syntax} #~@var{exp}
9597 @deffnx {Scheme Syntax} (gexp @var{exp})
9598 Return a G-expression containing @var{exp}. @var{exp} may contain one
9599 or more of the following forms:
9603 @itemx (ungexp @var{obj})
9604 Introduce a reference to @var{obj}. @var{obj} may have one of the
9605 supported types, for example a package or a
9606 derivation, in which case the @code{ungexp} form is replaced by its
9607 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
9609 If @var{obj} is a list, it is traversed and references to supported
9610 objects are substituted similarly.
9612 If @var{obj} is another gexp, its contents are inserted and its
9613 dependencies are added to those of the containing gexp.
9615 If @var{obj} is another kind of object, it is inserted as is.
9617 @item #$@var{obj}:@var{output}
9618 @itemx (ungexp @var{obj} @var{output})
9619 This is like the form above, but referring explicitly to the
9620 @var{output} of @var{obj}---this is useful when @var{obj} produces
9621 multiple outputs (@pxref{Packages with Multiple Outputs}).
9624 @itemx #+@var{obj}:output
9625 @itemx (ungexp-native @var{obj})
9626 @itemx (ungexp-native @var{obj} @var{output})
9627 Same as @code{ungexp}, but produces a reference to the @emph{native}
9628 build of @var{obj} when used in a cross compilation context.
9630 @item #$output[:@var{output}]
9631 @itemx (ungexp output [@var{output}])
9632 Insert a reference to derivation output @var{output}, or to the main
9633 output when @var{output} is omitted.
9635 This only makes sense for gexps passed to @code{gexp->derivation}.
9638 @itemx (ungexp-splicing @var{lst})
9639 Like the above, but splices the contents of @var{lst} inside the
9643 @itemx (ungexp-native-splicing @var{lst})
9644 Like the above, but refers to native builds of the objects listed in
9649 G-expressions created by @code{gexp} or @code{#~} are run-time objects
9650 of the @code{gexp?} type (see below).
9653 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
9654 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
9655 in their execution environment.
9657 Each item in @var{modules} can be the name of a module, such as
9658 @code{(guix build utils)}, or it can be a module name, followed by an
9659 arrow, followed by a file-like object:
9662 `((guix build utils)
9664 ((guix config) => ,(scheme-file "config.scm"
9665 #~(define-module @dots{}))))
9669 In the example above, the first two modules are taken from the search
9670 path, and the last one is created from the given file-like object.
9672 This form has @emph{lexical} scope: it has an effect on the gexps
9673 directly defined in @var{body}@dots{}, but not on those defined, say, in
9674 procedures called from @var{body}@dots{}.
9677 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
9678 Mark the gexps defined in @var{body}@dots{} as requiring
9679 @var{extensions} in their build and execution environment.
9680 @var{extensions} is typically a list of package objects such as those
9681 defined in the @code{(gnu packages guile)} module.
9683 Concretely, the packages listed in @var{extensions} are added to the
9684 load path while compiling imported modules in @var{body}@dots{}; they
9685 are also added to the load path of the gexp returned by
9689 @deffn {Scheme Procedure} gexp? @var{obj}
9690 Return @code{#t} if @var{obj} is a G-expression.
9693 G-expressions are meant to be written to disk, either as code building
9694 some derivation, or as plain files in the store. The monadic procedures
9695 below allow you to do that (@pxref{The Store Monad}, for more
9696 information about monads).
9698 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
9699 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
9700 [#:hash #f] [#:hash-algo #f] @
9701 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
9702 [#:module-path @code{%load-path}] @
9703 [#:effective-version "2.2"] @
9704 [#:references-graphs #f] [#:allowed-references #f] @
9705 [#:disallowed-references #f] @
9706 [#:leaked-env-vars #f] @
9707 [#:script-name (string-append @var{name} "-builder")] @
9708 [#:deprecation-warnings #f] @
9709 [#:local-build? #f] [#:substitutable? #t] @
9710 [#:properties '()] [#:guile-for-build #f]
9711 Return a derivation @var{name} that runs @var{exp} (a gexp) with
9712 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
9713 stored in a file called @var{script-name}. When @var{target} is true,
9714 it is used as the cross-compilation target triplet for packages referred
9717 @var{modules} is deprecated in favor of @code{with-imported-modules}.
9719 make @var{modules} available in the evaluation context of @var{exp};
9720 @var{modules} is a list of names of Guile modules searched in
9721 @var{module-path} to be copied in the store, compiled, and made available in
9722 the load path during the execution of @var{exp}---e.g., @code{((guix
9723 build utils) (guix build gnu-build-system))}.
9725 @var{effective-version} determines the string to use when adding extensions of
9726 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
9728 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
9731 When @var{references-graphs} is true, it must be a list of tuples of one of the
9735 (@var{file-name} @var{package})
9736 (@var{file-name} @var{package} @var{output})
9737 (@var{file-name} @var{derivation})
9738 (@var{file-name} @var{derivation} @var{output})
9739 (@var{file-name} @var{store-item})
9742 The right-hand-side of each element of @var{references-graphs} is automatically made
9743 an input of the build process of @var{exp}. In the build environment, each
9744 @var{file-name} contains the reference graph of the corresponding item, in a simple
9747 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
9748 In the latter case, the list denotes store items that the result is allowed to
9749 refer to. Any reference to another store item will lead to a build error.
9750 Similarly for @var{disallowed-references}, which can list items that must not be
9751 referenced by the outputs.
9753 @var{deprecation-warnings} determines whether to show deprecation warnings while
9754 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
9756 The other arguments are as for @code{derivation} (@pxref{Derivations}).
9759 @cindex file-like objects
9760 The @code{local-file}, @code{plain-file}, @code{computed-file},
9761 @code{program-file}, and @code{scheme-file} procedures below return
9762 @dfn{file-like objects}. That is, when unquoted in a G-expression,
9763 these objects lead to a file in the store. Consider this G-expression:
9766 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
9767 #$(local-file "/tmp/my-nscd.conf"))
9770 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
9771 to the store. Once expanded, for instance @i{via}
9772 @code{gexp->derivation}, the G-expression refers to that copy under
9773 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
9774 does not have any effect on what the G-expression does.
9775 @code{plain-file} can be used similarly; it differs in that the file
9776 content is directly passed as a string.
9778 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
9779 [#:recursive? #f] [#:select? (const #t)]
9780 Return an object representing local file @var{file} to add to the store;
9781 this object can be used in a gexp. If @var{file} is a literal string
9782 denoting a relative file name, it is looked up relative to the source
9783 file where it appears; if @var{file} is not a literal string, it is
9784 looked up relative to the current working directory at run time.
9785 @var{file} will be added to the store under @var{name}--by default the
9786 base name of @var{file}.
9788 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
9789 designates a flat file and @var{recursive?} is true, its contents are added, and its
9790 permission bits are kept.
9792 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
9793 @var{stat})} for each directory entry, where @var{file} is the entry's
9794 absolute file name and @var{stat} is the result of @code{lstat}; exclude
9795 entries for which @var{select?} does not return true.
9797 This is the declarative counterpart of the @code{interned-file} monadic
9798 procedure (@pxref{The Store Monad, @code{interned-file}}).
9801 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
9802 Return an object representing a text file called @var{name} with the given
9803 @var{content} (a string or a bytevector) to be added to the store.
9805 This is the declarative counterpart of @code{text-file}.
9808 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
9811 Return an object representing the store item @var{name}, a file or
9812 directory computed by @var{gexp}. When @var{local-build?} is true (the
9813 default), the derivation is built locally. @var{options} is a list of
9814 additional arguments to pass to @code{gexp->derivation}.
9816 This is the declarative counterpart of @code{gexp->derivation}.
9819 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
9820 [#:guile (default-guile)] [#:module-path %load-path] @
9821 [#:system (%current-system)] [#:target #f]
9822 Return an executable script @var{name} that runs @var{exp} using
9823 @var{guile}, with @var{exp}'s imported modules in its search path.
9824 Look up @var{exp}'s modules in @var{module-path}.
9826 The example below builds a script that simply invokes the @command{ls}
9830 (use-modules (guix gexp) (gnu packages base))
9832 (gexp->script "list-files"
9833 #~(execl #$(file-append coreutils "/bin/ls")
9837 When ``running'' it through the store (@pxref{The Store Monad,
9838 @code{run-with-store}}), we obtain a derivation that produces an
9839 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
9842 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
9844 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
9848 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
9849 [#:guile #f] [#:module-path %load-path]
9850 Return an object representing the executable store item @var{name} that
9851 runs @var{gexp}. @var{guile} is the Guile package used to execute that
9852 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
9854 This is the declarative counterpart of @code{gexp->script}.
9857 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
9858 [#:set-load-path? #t] [#:module-path %load-path] @
9860 [#:guile (default-guile)]
9861 Return a derivation that builds a file @var{name} containing @var{exp}.
9862 When @var{splice?} is true, @var{exp} is considered to be a list of
9863 expressions that will be spliced in the resulting file.
9865 When @var{set-load-path?} is true, emit code in the resulting file to
9866 set @code{%load-path} and @code{%load-compiled-path} to honor
9867 @var{exp}'s imported modules. Look up @var{exp}'s modules in
9870 The resulting file holds references to all the dependencies of @var{exp}
9871 or a subset thereof.
9874 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
9875 [#:splice? #f] [#:set-load-path? #t]
9876 Return an object representing the Scheme file @var{name} that contains
9879 This is the declarative counterpart of @code{gexp->file}.
9882 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
9883 Return as a monadic value a derivation that builds a text file
9884 containing all of @var{text}. @var{text} may list, in addition to
9885 strings, objects of any type that can be used in a gexp: packages,
9886 derivations, local file objects, etc. The resulting store file holds
9887 references to all these.
9889 This variant should be preferred over @code{text-file} anytime the file
9890 to create will reference items from the store. This is typically the
9891 case when building a configuration file that embeds store file names,
9895 (define (profile.sh)
9896 ;; Return the name of a shell script in the store that
9897 ;; initializes the 'PATH' environment variable.
9898 (text-file* "profile.sh"
9899 "export PATH=" coreutils "/bin:"
9900 grep "/bin:" sed "/bin\n"))
9903 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
9904 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
9905 preventing them from being garbage-collected during its lifetime.
9908 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
9909 Return an object representing store file @var{name} containing
9910 @var{text}. @var{text} is a sequence of strings and file-like objects,
9914 (mixed-text-file "profile"
9915 "export PATH=" coreutils "/bin:" grep "/bin")
9918 This is the declarative counterpart of @code{text-file*}.
9921 @deffn {Scheme Procedure} file-union @var{name} @var{files}
9922 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
9923 Each item in @var{files} must be a two-element list where the first element is the
9924 file name to use in the new directory, and the second element is a gexp
9925 denoting the target file. Here's an example:
9929 `(("hosts" ,(plain-file "hosts"
9930 "127.0.0.1 localhost"))
9931 ("bashrc" ,(plain-file "bashrc"
9932 "alias ls='ls --color=auto'"))))
9935 This yields an @code{etc} directory containing these two files.
9938 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
9939 Return a directory that is the union of @var{things}, where @var{things} is a list of
9940 file-like objects denoting directories. For example:
9943 (directory-union "guile+emacs" (list guile emacs))
9946 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
9949 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
9950 Return a file-like object that expands to the concatenation of @var{obj}
9951 and @var{suffix}, where @var{obj} is a lowerable object and each
9952 @var{suffix} is a string.
9954 As an example, consider this gexp:
9957 (gexp->script "run-uname"
9958 #~(system* #$(file-append coreutils
9962 The same effect could be achieved with:
9965 (gexp->script "run-uname"
9966 #~(system* (string-append #$coreutils
9970 There is one difference though: in the @code{file-append} case, the
9971 resulting script contains the absolute file name as a string, whereas in
9972 the second case, the resulting script contains a @code{(string-append
9973 @dots{})} expression to construct the file name @emph{at run time}.
9976 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
9977 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
9978 Bind @var{system} to the currently targeted system---e.g.,
9979 @code{"x86_64-linux"}---within @var{body}.
9981 In the second case, additionally bind @var{target} to the current
9982 cross-compilation target---a GNU triplet such as
9983 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
9986 @code{let-system} is useful in the occasional case where the object
9987 spliced into the gexp depends on the target system, as in this example:
9991 #+(let-system system
9992 (cond ((string-prefix? "armhf-" system)
9993 (file-append qemu "/bin/qemu-system-arm"))
9994 ((string-prefix? "x86_64-" system)
9995 (file-append qemu "/bin/qemu-system-x86_64"))
9998 "-net" "user" #$image)
10002 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
10003 This macro is similar to the @code{parameterize} form for
10004 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
10005 Guile Reference Manual}). The key difference is that it takes effect
10006 when the file-like object returned by @var{exp} is lowered to a
10007 derivation or store item.
10009 A typical use of @code{with-parameters} is to force the system in effect
10010 for a given object:
10013 (with-parameters ((%current-system "i686-linux"))
10017 The example above returns an object that corresponds to the i686 build
10018 of Coreutils, regardless of the current value of @code{%current-system}.
10022 Of course, in addition to gexps embedded in ``host'' code, there are
10023 also modules containing build tools. To make it clear that they are
10024 meant to be used in the build stratum, these modules are kept in the
10025 @code{(guix build @dots{})} name space.
10027 @cindex lowering, of high-level objects in gexps
10028 Internally, high-level objects are @dfn{lowered}, using their compiler,
10029 to either derivations or store items. For instance, lowering a package
10030 yields a derivation, and lowering a @code{plain-file} yields a store
10031 item. This is achieved using the @code{lower-object} monadic procedure.
10033 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
10035 Return as a value in @code{%store-monad} the derivation or store item
10036 corresponding to @var{obj} for @var{system}, cross-compiling for
10037 @var{target} if @var{target} is true. @var{obj} must be an object that
10038 has an associated gexp compiler, such as a @code{<package>}.
10041 @node Invoking guix repl
10042 @section Invoking @command{guix repl}
10044 @cindex REPL, read-eval-print loop, script
10045 The @command{guix repl} command makes it easier to program Guix in Guile
10046 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
10047 programming (@pxref{Using Guile Interactively,,, guile,
10048 GNU Guile Reference Manual}), or by running Guile scripts
10049 (@pxref{Running Guile Scripts,,, guile,
10050 GNU Guile Reference Manual}).
10051 Compared to just launching the @command{guile}
10052 command, @command{guix repl} guarantees that all the Guix modules and all its
10053 dependencies are available in the search path.
10055 The general syntax is:
10058 guix repl @var{options} [@var{file} @var{args}]
10061 When a @var{file} argument is provided, @var{file} is
10062 executed as a Guile scripts:
10065 guix repl my-script.scm
10068 To pass arguments to the script, use @code{--} to prevent them from
10069 being interpreted as arguments to @command{guix repl} itself:
10072 guix repl -- my-script.scm --input=foo.txt
10075 To make a script executable directly from the shell, using the guix
10076 executable that is on the user's search path, add the following two
10077 lines at the top of the script:
10080 @code{#!/usr/bin/env -S guix repl --}
10084 Without a file name argument, a Guile REPL is started:
10088 scheme@@(guile-user)> ,use (gnu packages base)
10089 scheme@@(guile-user)> coreutils
10090 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
10094 In addition, @command{guix repl} implements a simple machine-readable REPL
10095 protocol for use by @code{(guix inferior)}, a facility to interact with
10096 @dfn{inferiors}, separate processes running a potentially different revision
10099 The available options are as follows:
10102 @item --type=@var{type}
10103 @itemx -t @var{type}
10104 Start a REPL of the given @var{TYPE}, which can be one of the following:
10108 This is default, and it spawns a standard full-featured Guile REPL.
10110 Spawn a REPL that uses the machine-readable protocol. This is the protocol
10111 that the @code{(guix inferior)} module speaks.
10114 @item --listen=@var{endpoint}
10115 By default, @command{guix repl} reads from standard input and writes to
10116 standard output. When this option is passed, it will instead listen for
10117 connections on @var{endpoint}. Here are examples of valid options:
10120 @item --listen=tcp:37146
10121 Accept connections on localhost on port 37146.
10123 @item --listen=unix:/tmp/socket
10124 Accept connections on the Unix-domain socket @file{/tmp/socket}.
10127 @item --load-path=@var{directory}
10128 @itemx -L @var{directory}
10129 Add @var{directory} to the front of the package module search path
10130 (@pxref{Package Modules}).
10132 This allows users to define their own packages and make them visible to
10133 the script or REPL.
10136 Inhibit loading of the @file{~/.guile} file. By default, that
10137 configuration file is loaded when spawning a @code{guile} REPL.
10140 @c *********************************************************************
10144 This section describes Guix command-line utilities. Some of them are
10145 primarily targeted at developers and users who write new package
10146 definitions, while others are more generally useful. They complement
10147 the Scheme programming interface of Guix in a convenient way.
10150 * Invoking guix build:: Building packages from the command line.
10151 * Invoking guix edit:: Editing package definitions.
10152 * Invoking guix download:: Downloading a file and printing its hash.
10153 * Invoking guix hash:: Computing the cryptographic hash of a file.
10154 * Invoking guix import:: Importing package definitions.
10155 * Invoking guix refresh:: Updating package definitions.
10156 * Invoking guix lint:: Finding errors in package definitions.
10157 * Invoking guix size:: Profiling disk usage.
10158 * Invoking guix graph:: Visualizing the graph of packages.
10159 * Invoking guix publish:: Sharing substitutes.
10160 * Invoking guix challenge:: Challenging substitute servers.
10161 * Invoking guix copy:: Copying to and from a remote store.
10162 * Invoking guix container:: Process isolation.
10163 * Invoking guix weather:: Assessing substitute availability.
10164 * Invoking guix processes:: Listing client processes.
10167 @node Invoking guix build
10168 @section Invoking @command{guix build}
10170 @cindex package building
10171 @cindex @command{guix build}
10172 The @command{guix build} command builds packages or derivations and
10173 their dependencies, and prints the resulting store paths. Note that it
10174 does not modify the user's profile---this is the job of the
10175 @command{guix package} command (@pxref{Invoking guix package}). Thus,
10176 it is mainly useful for distribution developers.
10178 The general syntax is:
10181 guix build @var{options} @var{package-or-derivation}@dots{}
10184 As an example, the following command builds the latest versions of Emacs
10185 and of Guile, displays their build logs, and finally displays the
10186 resulting directories:
10189 guix build emacs guile
10192 Similarly, the following command builds all the available packages:
10195 guix build --quiet --keep-going \
10196 $(guix package -A | cut -f1,2 --output-delimiter=@@)
10199 @var{package-or-derivation} may be either the name of a package found in
10200 the software distribution such as @code{coreutils} or
10201 @code{coreutils@@8.20}, or a derivation such as
10202 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
10203 package with the corresponding name (and optionally version) is searched
10204 for among the GNU distribution modules (@pxref{Package Modules}).
10206 Alternatively, the @option{--expression} option may be used to specify a
10207 Scheme expression that evaluates to a package; this is useful when
10208 disambiguating among several same-named packages or package variants is
10211 There may be zero or more @var{options}. The available options are
10212 described in the subsections below.
10215 * Common Build Options:: Build options for most commands.
10216 * Package Transformation Options:: Creating variants of packages.
10217 * Additional Build Options:: Options specific to 'guix build'.
10218 * Debugging Build Failures:: Real life packaging experience.
10221 @node Common Build Options
10222 @subsection Common Build Options
10224 A number of options that control the build process are common to
10225 @command{guix build} and other commands that can spawn builds, such as
10226 @command{guix package} or @command{guix archive}. These are the
10231 @item --load-path=@var{directory}
10232 @itemx -L @var{directory}
10233 Add @var{directory} to the front of the package module search path
10234 (@pxref{Package Modules}).
10236 This allows users to define their own packages and make them visible to
10237 the command-line tools.
10239 @item --keep-failed
10241 Keep the build tree of failed builds. Thus, if a build fails, its build
10242 tree is kept under @file{/tmp}, in a directory whose name is shown at
10243 the end of the build log. This is useful when debugging build issues.
10244 @xref{Debugging Build Failures}, for tips and tricks on how to debug
10247 This option implies @option{--no-offload}, and it has no effect when
10248 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
10249 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
10253 Keep going when some of the derivations fail to build; return only once
10254 all the builds have either completed or failed.
10256 The default behavior is to stop as soon as one of the specified
10257 derivations has failed.
10261 Do not build the derivations.
10263 @anchor{fallback-option}
10265 When substituting a pre-built binary fails, fall back to building
10266 packages locally (@pxref{Substitution Failure}).
10268 @item --substitute-urls=@var{urls}
10269 @anchor{client-substitute-urls}
10270 Consider @var{urls} the whitespace-separated list of substitute source
10271 URLs, overriding the default list of URLs of @command{guix-daemon}
10272 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
10274 This means that substitutes may be downloaded from @var{urls}, provided
10275 they are signed by a key authorized by the system administrator
10276 (@pxref{Substitutes}).
10278 When @var{urls} is the empty string, substitutes are effectively
10281 @item --no-substitutes
10282 Do not use substitutes for build products. That is, always build things
10283 locally instead of allowing downloads of pre-built binaries
10284 (@pxref{Substitutes}).
10287 Do not ``graft'' packages. In practice, this means that package updates
10288 available as grafts are not applied. @xref{Security Updates}, for more
10289 information on grafts.
10291 @item --rounds=@var{n}
10292 Build each derivation @var{n} times in a row, and raise an error if
10293 consecutive build results are not bit-for-bit identical.
10295 This is a useful way to detect non-deterministic builds processes.
10296 Non-deterministic build processes are a problem because they make it
10297 practically impossible for users to @emph{verify} whether third-party
10298 binaries are genuine. @xref{Invoking guix challenge}, for more.
10300 When used in conjunction with @option{--keep-failed}, the differing
10301 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
10302 This makes it easy to look for differences between the two results.
10305 Do not use offload builds to other machines (@pxref{Daemon Offload
10306 Setup}). That is, always build things locally instead of offloading
10307 builds to remote machines.
10309 @item --max-silent-time=@var{seconds}
10310 When the build or substitution process remains silent for more than
10311 @var{seconds}, terminate it and report a build failure.
10313 By default, the daemon's setting is honored (@pxref{Invoking
10314 guix-daemon, @option{--max-silent-time}}).
10316 @item --timeout=@var{seconds}
10317 Likewise, when the build or substitution process lasts for more than
10318 @var{seconds}, terminate it and report a build failure.
10320 By default, the daemon's setting is honored (@pxref{Invoking
10321 guix-daemon, @option{--timeout}}).
10323 @c Note: This option is actually not part of %standard-build-options but
10324 @c most programs honor it.
10325 @cindex verbosity, of the command-line tools
10326 @cindex build logs, verbosity
10327 @item -v @var{level}
10328 @itemx --verbosity=@var{level}
10329 Use the given verbosity @var{level}, an integer. Choosing 0 means that
10330 no output is produced, 1 is for quiet output; 2 is similar to 1 but it
10331 additionally displays download URLs; 3 shows all the build log output on
10334 @item --cores=@var{n}
10336 Allow the use of up to @var{n} CPU cores for the build. The special
10337 value @code{0} means to use as many CPU cores as available.
10339 @item --max-jobs=@var{n}
10341 Allow at most @var{n} build jobs in parallel. @xref{Invoking
10342 guix-daemon, @option{--max-jobs}}, for details about this option and the
10343 equivalent @command{guix-daemon} option.
10345 @item --debug=@var{level}
10346 Produce debugging output coming from the build daemon. @var{level} must be an
10347 integer between 0 and 5; higher means more verbose output. Setting a level of
10348 4 or more may be helpful when debugging setup issues with the build daemon.
10352 Behind the scenes, @command{guix build} is essentially an interface to
10353 the @code{package-derivation} procedure of the @code{(guix packages)}
10354 module, and to the @code{build-derivations} procedure of the @code{(guix
10355 derivations)} module.
10357 In addition to options explicitly passed on the command line,
10358 @command{guix build} and other @command{guix} commands that support
10359 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
10361 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
10362 Users can define this variable to a list of command line options that
10363 will automatically be used by @command{guix build} and other
10364 @command{guix} commands that can perform builds, as in the example
10368 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
10371 These options are parsed independently, and the result is appended to
10372 the parsed command-line options.
10376 @node Package Transformation Options
10377 @subsection Package Transformation Options
10379 @cindex package variants
10380 Another set of command-line options supported by @command{guix build}
10381 and also @command{guix package} are @dfn{package transformation
10382 options}. These are options that make it possible to define @dfn{package
10383 variants}---for instance, packages built from different source code.
10384 This is a convenient way to create customized packages on the fly
10385 without having to type in the definitions of package variants
10386 (@pxref{Defining Packages}).
10388 Package transformation options are preserved across upgrades:
10389 @command{guix upgrade} attempts to apply transformation options
10390 initially used when creating the profile to the upgraded packages.
10392 The available options are listed below. Most commands support them and
10393 also support a @option{--help-transform} option that lists all the
10394 available options and a synopsis (these options are not shown in the
10395 @option{--help} output for brevity).
10399 @item --with-source=@var{source}
10400 @itemx --with-source=@var{package}=@var{source}
10401 @itemx --with-source=@var{package}@@@var{version}=@var{source}
10402 Use @var{source} as the source of @var{package}, and @var{version} as
10403 its version number.
10404 @var{source} must be a file name or a URL, as for @command{guix
10405 download} (@pxref{Invoking guix download}).
10407 When @var{package} is omitted,
10408 it is taken to be the package name specified on the
10409 command line that matches the base of @var{source}---e.g.,
10410 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
10411 package is @code{guile}.
10413 Likewise, when @var{version} is omitted, the version string is inferred from
10414 @var{source}; in the previous example, it is @code{2.0.10}.
10416 This option allows users to try out versions of packages other than the
10417 one provided by the distribution. The example below downloads
10418 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
10419 the @code{ed} package:
10422 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
10425 As a developer, @option{--with-source} makes it easy to test release
10429 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
10432 @dots{} or to build from a checkout in a pristine environment:
10435 $ git clone git://git.sv.gnu.org/guix.git
10436 $ guix build guix --with-source=guix@@1.0=./guix
10439 @item --with-input=@var{package}=@var{replacement}
10440 Replace dependency on @var{package} by a dependency on
10441 @var{replacement}. @var{package} must be a package name, and
10442 @var{replacement} must be a package specification such as @code{guile}
10443 or @code{guile@@1.8}.
10445 For instance, the following command builds Guix, but replaces its
10446 dependency on the current stable version of Guile with a dependency on
10447 the legacy version of Guile, @code{guile@@2.0}:
10450 guix build --with-input=guile=guile@@2.0 guix
10453 This is a recursive, deep replacement. So in this example, both
10454 @code{guix} and its dependency @code{guile-json} (which also depends on
10455 @code{guile}) get rebuilt against @code{guile@@2.0}.
10457 This is implemented using the @code{package-input-rewriting} Scheme
10458 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
10460 @item --with-graft=@var{package}=@var{replacement}
10461 This is similar to @option{--with-input} but with an important difference:
10462 instead of rebuilding the whole dependency chain, @var{replacement} is
10463 built and then @dfn{grafted} onto the binaries that were initially
10464 referring to @var{package}. @xref{Security Updates}, for more
10465 information on grafts.
10467 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
10468 and all its dependencies, replacing references to the version of GnuTLS
10469 they currently refer to:
10472 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
10475 This has the advantage of being much faster than rebuilding everything.
10476 But there is a caveat: it works if and only if @var{package} and
10477 @var{replacement} are strictly compatible---for example, if they provide
10478 a library, the application binary interface (ABI) of those libraries
10479 must be compatible. If @var{replacement} is somehow incompatible with
10480 @var{package}, then the resulting package may be unusable. Use with
10483 @cindex debugging info, rebuilding
10484 @item --with-debug-info=@var{package}
10485 Build @var{package} in a way that preserves its debugging info and graft
10486 it onto packages that depend on it. This is useful if @var{package}
10487 does not already provide debugging info as a @code{debug} output
10488 (@pxref{Installing Debugging Files}).
10490 For example, suppose you're experiencing a crash in Inkscape and would
10491 like to see what's up in GLib, a library deep down in Inkscape's
10492 dependency graph. GLib lacks a @code{debug} output, so debugging is
10493 tough. Fortunately, you rebuild GLib with debugging info and tack it on
10497 guix install inkscape --with-debug-info=glib
10500 Only GLib needs to be recompiled so this takes a reasonable amount of
10501 time. @xref{Installing Debugging Files}, for more info.
10504 Under the hood, this option works by passing the @samp{#:strip-binaries?
10505 #f} to the build system of the package of interest (@pxref{Build
10506 Systems}). Most build systems support that option but some do not. In
10507 that case, an error is raised.
10509 Likewise, if a C/C++ package is built without @code{-g} (which is rarely
10510 the case), debugging info will remain unavailable even when
10511 @code{#:strip-binaries?} is false.
10514 @cindex tool chain, changing the build tool chain of a package
10515 @item --with-c-toolchain=@var{package}=@var{toolchain}
10516 This option changes the compilation of @var{package} and everything that
10517 depends on it so that they get built with @var{toolchain} instead of the
10518 default GNU tool chain for C/C++.
10520 Consider this example:
10523 guix build octave-cli \
10524 --with-c-toolchain=fftw=gcc-toolchain@@10 \
10525 --with-c-toolchain=fftwf=gcc-toolchain@@10
10528 The command above builds a variant of the @code{fftw} and @code{fftwf}
10529 packages using version 10 of @code{gcc-toolchain} instead of the default
10530 tool chain, and then builds a variant of the GNU@tie{}Octave
10531 command-line interface using them. GNU@tie{}Octave itself is also built
10532 with @code{gcc-toolchain@@10}.
10534 This other example builds the Hardware Locality (@code{hwloc}) library
10535 and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
10539 guix build --with-c-toolchain=hwloc=clang-toolchain \
10540 intel-mpi-benchmarks
10544 There can be application binary interface (ABI) incompatibilities among
10545 tool chains. This is particularly true of the C++ standard library and
10546 run-time support libraries such as that of OpenMP@. By rebuilding all
10547 dependents with the same tool chain, @option{--with-c-toolchain} minimizes
10548 the risks of incompatibility but cannot entirely eliminate them. Choose
10549 @var{package} wisely.
10552 @item --with-git-url=@var{package}=@var{url}
10553 @cindex Git, using the latest commit
10554 @cindex latest commit, building
10555 Build @var{package} from the latest commit of the @code{master} branch of the
10556 Git repository at @var{url}. Git sub-modules of the repository are fetched,
10559 For example, the following command builds the NumPy Python library against the
10560 latest commit of the master branch of Python itself:
10563 guix build python-numpy \
10564 --with-git-url=python=https://github.com/python/cpython
10567 This option can also be combined with @option{--with-branch} or
10568 @option{--with-commit} (see below).
10570 @cindex continuous integration
10571 Obviously, since it uses the latest commit of the given branch, the result of
10572 such a command varies over time. Nevertheless it is a convenient way to
10573 rebuild entire software stacks against the latest commit of one or more
10574 packages. This is particularly useful in the context of continuous
10577 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
10578 consecutive accesses to the same repository. You may want to clean it up once
10579 in a while to save disk space.
10581 @item --with-branch=@var{package}=@var{branch}
10582 Build @var{package} from the latest commit of @var{branch}. If the
10583 @code{source} field of @var{package} is an origin with the @code{git-fetch}
10584 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
10585 repository URL is taken from that @code{source}. Otherwise you have to use
10586 @option{--with-git-url} to specify the URL of the Git repository.
10588 For instance, the following command builds @code{guile-sqlite3} from the
10589 latest commit of its @code{master} branch, and then builds @code{guix} (which
10590 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
10591 specific @code{guile-sqlite3} build:
10594 guix build --with-branch=guile-sqlite3=master cuirass
10597 @item --with-commit=@var{package}=@var{commit}
10598 This is similar to @option{--with-branch}, except that it builds from
10599 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
10600 Git commit SHA1 identifier or a tag.
10602 @item --with-patch=@var{package}=@var{file}
10603 Add @var{file} to the list of patches applied to @var{package}, where
10604 @var{package} is a spec such as @code{python@@3.8} or @code{glibc}.
10605 @var{file} must contain a patch; it is applied with the flags specified
10606 in the @code{origin} of @var{package} (@pxref{origin Reference}), which
10607 by default includes @code{-p1} (@pxref{patch Directories,,, diffutils,
10608 Comparing and Merging Files}).
10610 As an example, the command below rebuilds Coreutils with the GNU C
10611 Library (glibc) patched with the given patch:
10614 guix build coreutils --with-patch=glibc=./glibc-frob.patch
10617 In this example, glibc itself as well as everything that leads to
10618 Coreutils in the dependency graph is rebuilt.
10620 @cindex upstream, latest version
10621 @item --with-latest=@var{package}
10622 So you like living on the bleeding edge? This option is for you! It
10623 replaces occurrences of @var{package} in the dependency graph with its
10624 latest upstream version, as reported by @command{guix refresh}
10625 (@pxref{Invoking guix refresh}).
10627 It does so by determining the latest upstream release of @var{package}
10628 (if possible), downloading it, and authenticating it @emph{if} it comes
10629 with an OpenPGP signature.
10631 As an example, the command below builds Guix against the latest version
10635 guix build guix --with-latest=guile-json
10638 There are limitations. First, in cases where the tool cannot or does
10639 not know how to authenticate source code, you are at risk of running
10640 malicious code; a warning is emitted in this case. Second, this option
10641 simply changes the source used in the existing package definitions,
10642 which is not always sufficient: there might be additional dependencies
10643 that need to be added, patches to apply, and more generally the quality
10644 assurance work that Guix developers normally do will be missing.
10646 You've been warned! In all the other cases, it's a snappy way to stay
10647 on top. We encourage you to submit patches updating the actual package
10648 definitions once you have successfully tested an upgrade
10649 (@pxref{Contributing}).
10651 @cindex test suite, skipping
10652 @item --without-tests=@var{package}
10653 Build @var{package} without running its tests. This can be useful in
10654 situations where you want to skip the lengthy test suite of a
10655 intermediate package, or if a package's test suite fails in a
10656 non-deterministic fashion. It should be used with care because running
10657 the test suite is a good way to ensure a package is working as intended.
10659 Turning off tests leads to a different store item. Consequently, when
10660 using this option, anything that depends on @var{package} must be
10661 rebuilt, as in this example:
10664 guix install --without-tests=python python-notebook
10667 The command above installs @code{python-notebook} on top of
10668 @code{python} built without running its test suite. To do so, it also
10669 rebuilds everything that depends on @code{python}, including
10670 @code{python-notebook} itself.
10672 Internally, @option{--without-tests} relies on changing the
10673 @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
10674 Systems}). Note that some packages use a customized @code{check} phase
10675 that does not respect a @code{#:tests? #f} setting. Therefore,
10676 @option{--without-tests} has no effect on these packages.
10680 Wondering how to achieve the same effect using Scheme code, for example
10681 in your manifest, or how to write your own package transformation?
10682 @xref{Defining Package Variants}, for an overview of the programming
10683 interfaces available.
10685 @node Additional Build Options
10686 @subsection Additional Build Options
10688 The command-line options presented below are specific to @command{guix
10695 Build quietly, without displaying the build log; this is equivalent to
10696 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
10697 (or similar) and can always be retrieved using the @option{--log-file} option.
10699 @item --file=@var{file}
10700 @itemx -f @var{file}
10701 Build the package, derivation, or other file-like object that the code within
10702 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
10704 As an example, @var{file} might contain a package definition like this
10705 (@pxref{Defining Packages}):
10708 @include package-hello.scm
10711 The @var{file} may also contain a JSON representation of one or more
10712 package definitions. Running @code{guix build -f} on @file{hello.json}
10713 with the following contents would result in building the packages
10714 @code{myhello} and @code{greeter}:
10717 @verbatiminclude package-hello.json
10720 @item --manifest=@var{manifest}
10721 @itemx -m @var{manifest}
10722 Build all packages listed in the given @var{manifest}
10723 (@pxref{profile-manifest, @option{--manifest}}).
10725 @item --expression=@var{expr}
10726 @itemx -e @var{expr}
10727 Build the package or derivation @var{expr} evaluates to.
10729 For example, @var{expr} may be @code{(@@ (gnu packages guile)
10730 guile-1.8)}, which unambiguously designates this specific variant of
10731 version 1.8 of Guile.
10733 Alternatively, @var{expr} may be a G-expression, in which case it is used
10734 as a build program passed to @code{gexp->derivation}
10735 (@pxref{G-Expressions}).
10737 Lastly, @var{expr} may refer to a zero-argument monadic procedure
10738 (@pxref{The Store Monad}). The procedure must return a derivation as a
10739 monadic value, which is then passed through @code{run-with-store}.
10743 Build the source derivations of the packages, rather than the packages
10746 For instance, @code{guix build -S gcc} returns something like
10747 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
10750 The returned source tarball is the result of applying any patches and
10751 code snippets specified in the package @code{origin} (@pxref{Defining
10754 @cindex source, verification
10755 As with other derivations, the result of building a source derivation
10756 can be verified using the @option{--check} option (@pxref{build-check}).
10757 This is useful to validate that a (potentially already built or
10758 substituted, thus cached) package source matches against its declared
10761 Note that @command{guix build -S} compiles the sources only of the
10762 specified packages. They do not include the sources of statically
10763 linked dependencies and by themselves are insufficient for reproducing
10767 Fetch and return the source of @var{package-or-derivation} and all their
10768 dependencies, recursively. This is a handy way to obtain a local copy
10769 of all the source code needed to build @var{packages}, allowing you to
10770 eventually build them even without network access. It is an extension
10771 of the @option{--source} option and can accept one of the following
10772 optional argument values:
10776 This value causes the @option{--sources} option to behave in the same way
10777 as the @option{--source} option.
10780 Build the source derivations of all packages, including any source that
10781 might be listed as @code{inputs}. This is the default value.
10784 $ guix build --sources tzdata
10785 The following derivations will be built:
10786 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
10787 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
10791 Build the source derivations of all packages, as well of all transitive
10792 inputs to the packages. This can be used e.g.@: to
10793 prefetch package source for later offline building.
10796 $ guix build --sources=transitive tzdata
10797 The following derivations will be built:
10798 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
10799 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
10800 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
10801 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
10802 /gnu/store/@dots{}-make-4.1.tar.xz.drv
10803 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
10809 @item --system=@var{system}
10810 @itemx -s @var{system}
10811 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
10812 the system type of the build host. The @command{guix build} command allows
10813 you to repeat this option several times, in which case it builds for all the
10814 specified systems; other commands ignore extraneous @option{-s} options.
10817 The @option{--system} flag is for @emph{native} compilation and must not
10818 be confused with cross-compilation. See @option{--target} below for
10819 information on cross-compilation.
10822 An example use of this is on Linux-based systems, which can emulate
10823 different personalities. For instance, passing
10824 @option{--system=i686-linux} on an @code{x86_64-linux} system or
10825 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
10826 you to build packages in a complete 32-bit environment.
10829 Building for an @code{armhf-linux} system is unconditionally enabled on
10830 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
10831 allow for this functionality, notably the ThunderX.
10834 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
10835 is enabled (@pxref{Virtualization Services,
10836 @code{qemu-binfmt-service-type}}), you can build for any system for
10837 which a QEMU @code{binfmt_misc} handler is installed.
10839 Builds for a system other than that of the machine you are using can
10840 also be offloaded to a remote machine of the right architecture.
10841 @xref{Daemon Offload Setup}, for more information on offloading.
10843 @item --target=@var{triplet}
10844 @cindex cross-compilation
10845 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
10846 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
10847 configuration triplets,, autoconf, Autoconf}).
10849 @anchor{build-check}
10851 @cindex determinism, checking
10852 @cindex reproducibility, checking
10853 Rebuild @var{package-or-derivation}, which are already available in the
10854 store, and raise an error if the build results are not bit-for-bit
10857 This mechanism allows you to check whether previously installed
10858 substitutes are genuine (@pxref{Substitutes}), or whether the build result
10859 of a package is deterministic. @xref{Invoking guix challenge}, for more
10860 background information and tools.
10862 When used in conjunction with @option{--keep-failed}, the differing
10863 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
10864 This makes it easy to look for differences between the two results.
10867 @cindex repairing store items
10868 @cindex corruption, recovering from
10869 Attempt to repair the specified store items, if they are corrupt, by
10870 re-downloading or rebuilding them.
10872 This operation is not atomic and thus restricted to @code{root}.
10874 @item --derivations
10876 Return the derivation paths, not the output paths, of the given
10879 @item --root=@var{file}
10880 @itemx -r @var{file}
10881 @cindex GC roots, adding
10882 @cindex garbage collector roots, adding
10883 Make @var{file} a symlink to the result, and register it as a garbage
10886 Consequently, the results of this @command{guix build} invocation are
10887 protected from garbage collection until @var{file} is removed. When
10888 that option is omitted, build results are eligible for garbage
10889 collection as soon as the build completes. @xref{Invoking guix gc}, for
10893 @cindex build logs, access
10894 Return the build log file names or URLs for the given
10895 @var{package-or-derivation}, or raise an error if build logs are
10898 This works regardless of how packages or derivations are specified. For
10899 instance, the following invocations are equivalent:
10902 guix build --log-file $(guix build -d guile)
10903 guix build --log-file $(guix build guile)
10904 guix build --log-file guile
10905 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
10908 If a log is unavailable locally, and unless @option{--no-substitutes} is
10909 passed, the command looks for a corresponding log on one of the
10910 substitute servers (as specified with @option{--substitute-urls}).
10912 So for instance, imagine you want to see the build log of GDB on MIPS,
10913 but you are actually on an @code{x86_64} machine:
10916 $ guix build --log-file gdb -s aarch64-linux
10917 https://@value{SUBSTITUTE-SERVER-1}/log/@dots{}-gdb-7.10
10920 You can freely access a huge library of build logs!
10923 @node Debugging Build Failures
10924 @subsection Debugging Build Failures
10926 @cindex build failures, debugging
10927 When defining a new package (@pxref{Defining Packages}), you will
10928 probably find yourself spending some time debugging and tweaking the
10929 build until it succeeds. To do that, you need to operate the build
10930 commands yourself in an environment as close as possible to the one the
10933 To that end, the first thing to do is to use the @option{--keep-failed}
10934 or @option{-K} option of @command{guix build}, which will keep the
10935 failed build tree in @file{/tmp} or whatever directory you specified as
10936 @env{TMPDIR} (@pxref{Common Build Options, @option{--keep-failed}}).
10938 From there on, you can @command{cd} to the failed build tree and source
10939 the @file{environment-variables} file, which contains all the
10940 environment variable definitions that were in place when the build
10941 failed. So let's say you're debugging a build failure in package
10942 @code{foo}; a typical session would look like this:
10945 $ guix build foo -K
10946 @dots{} @i{build fails}
10947 $ cd /tmp/guix-build-foo.drv-0
10948 $ source ./environment-variables
10952 Now, you can invoke commands as if you were the daemon (almost) and
10953 troubleshoot your build process.
10955 Sometimes it happens that, for example, a package's tests pass when you
10956 run them manually but they fail when the daemon runs them. This can
10957 happen because the daemon runs builds in containers where, unlike in our
10958 environment above, network access is missing, @file{/bin/sh} does not
10959 exist, etc. (@pxref{Build Environment Setup}).
10961 In such cases, you may need to run inspect the build process from within
10962 a container similar to the one the build daemon creates:
10965 $ guix build -K foo
10967 $ cd /tmp/guix-build-foo.drv-0
10968 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
10969 [env]# source ./environment-variables
10973 Here, @command{guix environment -C} creates a container and spawns a new
10974 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
10975 strace gdb} part adds the @command{strace} and @command{gdb} commands to
10976 the container, which you may find handy while debugging. The
10977 @option{--no-grafts} option makes sure we get the exact same
10978 environment, with ungrafted packages (@pxref{Security Updates}, for more
10981 To get closer to a container like that used by the build daemon, we can
10982 remove @file{/bin/sh}:
10988 (Don't worry, this is harmless: this is all happening in the throw-away
10989 container created by @command{guix environment}.)
10991 The @command{strace} command is probably not in the search path, but we
10995 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
10998 In this way, not only you will have reproduced the environment variables
10999 the daemon uses, you will also be running the build process in a container
11000 similar to the one the daemon uses.
11003 @node Invoking guix edit
11004 @section Invoking @command{guix edit}
11006 @cindex @command{guix edit}
11007 @cindex package definition, editing
11008 So many packages, so many source files! The @command{guix edit} command
11009 facilitates the life of users and packagers by pointing their editor at
11010 the source file containing the definition of the specified packages.
11014 guix edit gcc@@4.9 vim
11018 launches the program specified in the @env{VISUAL} or in the
11019 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
11022 If you are using a Guix Git checkout (@pxref{Building from Git}), or
11023 have created your own packages on @env{GUIX_PACKAGE_PATH}
11024 (@pxref{Package Modules}), you will be able to edit the package
11025 recipes. In other cases, you will be able to examine the read-only recipes
11026 for packages currently in the store.
11028 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
11029 @option{--load-path=@var{directory}} (or in short @option{-L
11030 @var{directory}}) allows you to add @var{directory} to the front of the
11031 package module search path and so make your own packages visible.
11033 @node Invoking guix download
11034 @section Invoking @command{guix download}
11036 @cindex @command{guix download}
11037 @cindex downloading package sources
11038 When writing a package definition, developers typically need to download
11039 a source tarball, compute its SHA256 hash, and write that
11040 hash in the package definition (@pxref{Defining Packages}). The
11041 @command{guix download} tool helps with this task: it downloads a file
11042 from the given URI, adds it to the store, and prints both its file name
11043 in the store and its SHA256 hash.
11045 The fact that the downloaded file is added to the store saves bandwidth:
11046 when the developer eventually tries to build the newly defined package
11047 with @command{guix build}, the source tarball will not have to be
11048 downloaded again because it is already in the store. It is also a
11049 convenient way to temporarily stash files, which may be deleted
11050 eventually (@pxref{Invoking guix gc}).
11052 The @command{guix download} command supports the same URIs as used in
11053 package definitions. In particular, it supports @code{mirror://} URIs.
11054 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
11055 Guile bindings for GnuTLS are available in the user's environment; when
11056 they are not available, an error is raised. @xref{Guile Preparations,
11057 how to install the GnuTLS bindings for Guile,, gnutls-guile,
11058 GnuTLS-Guile}, for more information.
11060 @command{guix download} verifies HTTPS server certificates by loading
11061 the certificates of X.509 authorities from the directory pointed to by
11062 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
11063 Certificates}), unless @option{--no-check-certificate} is used.
11065 The following options are available:
11068 @item --hash=@var{algorithm}
11069 @itemx -H @var{algorithm}
11070 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
11071 hash}, for more information.
11073 @item --format=@var{fmt}
11074 @itemx -f @var{fmt}
11075 Write the hash in the format specified by @var{fmt}. For more
11076 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
11078 @item --no-check-certificate
11079 Do not validate the X.509 certificates of HTTPS servers.
11081 When using this option, you have @emph{absolutely no guarantee} that you
11082 are communicating with the authentic server responsible for the given
11083 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
11085 @item --output=@var{file}
11086 @itemx -o @var{file}
11087 Save the downloaded file to @var{file} instead of adding it to the
11091 @node Invoking guix hash
11092 @section Invoking @command{guix hash}
11094 @cindex @command{guix hash}
11095 The @command{guix hash} command computes the hash of a file.
11096 It is primarily a convenience tool for anyone contributing to the
11097 distribution: it computes the cryptographic hash of a file, which can be
11098 used in the definition of a package (@pxref{Defining Packages}).
11100 The general syntax is:
11103 guix hash @var{option} @var{file}
11106 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
11107 hash of data read from standard input. @command{guix hash} has the
11112 @item --hash=@var{algorithm}
11113 @itemx -H @var{algorithm}
11114 Compute a hash using the specified @var{algorithm}, @code{sha256} by
11117 @var{algorithm} must the name of a cryptographic hash algorithm
11118 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
11119 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
11120 Reference Manual}).
11122 @item --format=@var{fmt}
11123 @itemx -f @var{fmt}
11124 Write the hash in the format specified by @var{fmt}.
11126 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
11127 (@code{hex} and @code{hexadecimal} can be used as well).
11129 If the @option{--format} option is not specified, @command{guix hash}
11130 will output the hash in @code{nix-base32}. This representation is used
11131 in the definitions of packages.
11135 Compute the hash on @var{file} recursively.
11137 In this case, the hash is computed on an archive containing @var{file},
11138 including its children if it is a directory. Some of the metadata of
11139 @var{file} is part of the archive; for instance, when @var{file} is a
11140 regular file, the hash is different depending on whether @var{file} is
11141 executable or not. Metadata such as time stamps has no impact on the
11142 hash (@pxref{Invoking guix archive}).
11143 @c FIXME: Replace xref above with xref to an ``Archive'' section when
11146 @item --exclude-vcs
11148 When combined with @option{--recursive}, exclude version control system
11149 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
11152 As an example, here is how you would compute the hash of a Git checkout,
11153 which is useful when using the @code{git-fetch} method (@pxref{origin
11157 $ git clone http://example.org/foo.git
11163 @node Invoking guix import
11164 @section Invoking @command{guix import}
11166 @cindex importing packages
11167 @cindex package import
11168 @cindex package conversion
11169 @cindex Invoking @command{guix import}
11170 The @command{guix import} command is useful for people who would like to
11171 add a package to the distribution with as little work as
11172 possible---a legitimate demand. The command knows of a few
11173 repositories from which it can ``import'' package metadata. The result
11174 is a package definition, or a template thereof, in the format we know
11175 (@pxref{Defining Packages}).
11177 The general syntax is:
11180 guix import @var{importer} @var{options}@dots{}
11183 @var{importer} specifies the source from which to import package
11184 metadata, and @var{options} specifies a package identifier and other
11185 options specific to @var{importer}.
11187 Some of the importers rely on the ability to run the @command{gpgv} command.
11188 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
11191 Currently, the available ``importers'' are:
11195 Import metadata for the given GNU package. This provides a template
11196 for the latest version of that GNU package, including the hash of its
11197 source tarball, and its canonical synopsis and description.
11199 Additional information such as the package dependencies and its
11200 license needs to be figured out manually.
11202 For example, the following command returns a package definition for
11206 guix import gnu hello
11209 Specific command-line options are:
11212 @item --key-download=@var{policy}
11213 As for @command{guix refresh}, specify the policy to handle missing
11214 OpenPGP keys when verifying the package signature. @xref{Invoking guix
11215 refresh, @option{--key-download}}.
11220 Import metadata from the @uref{https://pypi.python.org/, Python Package
11221 Index}. Information is taken from the JSON-formatted description
11222 available at @code{pypi.python.org} and usually includes all the relevant
11223 information, including package dependencies. For maximum efficiency, it
11224 is recommended to install the @command{unzip} utility, so that the
11225 importer can unzip Python wheels and gather data from them.
11227 The command below imports metadata for the @code{itsdangerous} Python
11231 guix import pypi itsdangerous
11237 Traverse the dependency graph of the given upstream package recursively
11238 and generate package expressions for all those packages that are not yet
11244 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
11245 is taken from the JSON-formatted description available at
11246 @code{rubygems.org} and includes most relevant information, including
11247 runtime dependencies. There are some caveats, however. The metadata
11248 doesn't distinguish between synopses and descriptions, so the same string
11249 is used for both fields. Additionally, the details of non-Ruby
11250 dependencies required to build native extensions is unavailable and left
11251 as an exercise to the packager.
11253 The command below imports metadata for the @code{rails} Ruby package:
11256 guix import gem rails
11262 Traverse the dependency graph of the given upstream package recursively
11263 and generate package expressions for all those packages that are not yet
11269 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
11270 Information is taken from the JSON-formatted metadata provided through
11271 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
11272 relevant information, such as module dependencies. License information
11273 should be checked closely. If Perl is available in the store, then the
11274 @code{corelist} utility will be used to filter core modules out of the
11275 list of dependencies.
11277 The command command below imports metadata for the Acme::Boolean Perl
11281 guix import cpan Acme::Boolean
11286 @cindex Bioconductor
11287 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
11288 central repository for the @uref{https://r-project.org, GNU@tie{}R
11289 statistical and graphical environment}.
11291 Information is extracted from the @file{DESCRIPTION} file of the package.
11293 The command command below imports metadata for the Cairo R package:
11296 guix import cran Cairo
11299 When @option{--recursive} is added, the importer will traverse the
11300 dependency graph of the given upstream package recursively and generate
11301 package expressions for all those packages that are not yet in Guix.
11303 When @option{--style=specification} is added, the importer will generate
11304 package definitions whose inputs are package specifications instead of
11305 references to package variables. This is useful when generated package
11306 definitions are to be appended to existing user modules, as the list of
11307 used package modules need not be changed. The default is
11308 @option{--style=variable}.
11310 When @option{--archive=bioconductor} is added, metadata is imported from
11311 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
11312 packages for the analysis and comprehension of high-throughput
11313 genomic data in bioinformatics.
11315 Information is extracted from the @file{DESCRIPTION} file contained in the
11318 The command below imports metadata for the GenomicRanges R package:
11321 guix import cran --archive=bioconductor GenomicRanges
11324 Finally, you can also import R packages that have not yet been published on
11325 CRAN or Bioconductor as long as they are in a git repository. Use
11326 @option{--archive=git} followed by the URL of the git repository:
11329 guix import cran --archive=git https://github.com/immunogenomics/harmony
11335 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
11336 comprehensive TeX archive network for TeX packages that are part of the
11337 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
11339 Information about the package is obtained through the XML API provided
11340 by CTAN, while the source code is downloaded from the SVN repository of
11341 the Tex Live project. This is done because the CTAN does not keep
11342 versioned archives.
11344 The command command below imports metadata for the @code{fontspec}
11348 guix import texlive fontspec
11351 When @option{--archive=@var{directory}} is added, the source code is
11352 downloaded not from the @file{latex} sub-directory of the
11353 @file{texmf-dist/source} tree in the TeX Live SVN repository, but from
11354 the specified sibling @var{directory} under the same root.
11356 The command below imports metadata for the @code{ifxetex} package from
11357 CTAN while fetching the sources from the directory
11358 @file{texmf/source/generic}:
11361 guix import texlive --archive=generic ifxetex
11365 @cindex JSON, import
11366 Import package metadata from a local JSON file. Consider the following
11367 example package definition in JSON format:
11373 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
11374 "build-system": "gnu",
11375 "home-page": "https://www.gnu.org/software/hello/",
11376 "synopsis": "Hello, GNU world: An example GNU package",
11377 "description": "GNU Hello prints a greeting.",
11378 "license": "GPL-3.0+",
11379 "native-inputs": ["gettext"]
11383 The field names are the same as for the @code{<package>} record
11384 (@xref{Defining Packages}). References to other packages are provided
11385 as JSON lists of quoted package specification strings such as
11386 @code{guile} or @code{guile@@2.0}.
11388 The importer also supports a more explicit source definition using the
11389 common fields for @code{<origin>} records:
11395 "method": "url-fetch",
11396 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
11398 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
11405 The command below reads metadata from the JSON file @code{hello.json}
11406 and outputs a package expression:
11409 guix import json hello.json
11414 Import metadata from the Haskell community's central package archive
11415 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
11416 Cabal files and includes all the relevant information, including package
11419 Specific command-line options are:
11424 Read a Cabal file from standard input.
11425 @item --no-test-dependencies
11427 Do not include dependencies required only by the test suites.
11428 @item --cabal-environment=@var{alist}
11429 @itemx -e @var{alist}
11430 @var{alist} is a Scheme alist defining the environment in which the
11431 Cabal conditionals are evaluated. The accepted keys are: @code{os},
11432 @code{arch}, @code{impl} and a string representing the name of a flag.
11433 The value associated with a flag has to be either the symbol
11434 @code{true} or @code{false}. The value associated with other keys
11435 has to conform to the Cabal file format definition. The default value
11436 associated with the keys @code{os}, @code{arch} and @code{impl} is
11437 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
11440 Traverse the dependency graph of the given upstream package recursively
11441 and generate package expressions for all those packages that are not yet
11445 The command below imports metadata for the latest version of the
11446 HTTP Haskell package without including test dependencies and
11447 specifying the value of the flag @samp{network-uri} as @code{false}:
11450 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
11453 A specific package version may optionally be specified by following the
11454 package name by an at-sign and a version number as in the following example:
11457 guix import hackage mtl@@2.1.3.1
11462 The @code{stackage} importer is a wrapper around the @code{hackage} one.
11463 It takes a package name, looks up the package version included in a
11464 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
11465 release and uses the @code{hackage} importer to retrieve its metadata.
11466 Note that it is up to you to select an LTS release compatible with the
11467 GHC compiler used by Guix.
11469 Specific command-line options are:
11472 @item --no-test-dependencies
11474 Do not include dependencies required only by the test suites.
11475 @item --lts-version=@var{version}
11476 @itemx -l @var{version}
11477 @var{version} is the desired LTS release version. If omitted the latest
11481 Traverse the dependency graph of the given upstream package recursively
11482 and generate package expressions for all those packages that are not yet
11486 The command below imports metadata for the HTTP Haskell package
11487 included in the LTS Stackage release version 7.18:
11490 guix import stackage --lts-version=7.18 HTTP
11495 Import metadata from an Emacs Lisp Package Archive (ELPA) package
11496 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
11498 Specific command-line options are:
11501 @item --archive=@var{repo}
11502 @itemx -a @var{repo}
11503 @var{repo} identifies the archive repository from which to retrieve the
11504 information. Currently the supported repositories and their identifiers
11508 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
11509 identifier. This is the default.
11511 Packages from @code{elpa.gnu.org} are signed with one of the keys
11512 contained in the GnuPG keyring at
11513 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
11514 @code{emacs} package (@pxref{Package Installation, ELPA package
11515 signatures,, emacs, The GNU Emacs Manual}).
11518 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
11519 @code{melpa-stable} identifier.
11522 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
11528 Traverse the dependency graph of the given upstream package recursively
11529 and generate package expressions for all those packages that are not yet
11535 Import metadata from the crates.io Rust package repository
11536 @uref{https://crates.io, crates.io}, as in this example:
11539 guix import crate blake2-rfc
11542 The crate importer also allows you to specify a version string:
11545 guix import crate constant-time-eq@@0.1.0
11548 Additional options include:
11553 Traverse the dependency graph of the given upstream package recursively
11554 and generate package expressions for all those packages that are not yet
11561 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
11562 repository used by the OCaml community.
11564 Additional options include:
11569 Traverse the dependency graph of the given upstream package recursively
11570 and generate package expressions for all those packages that are not yet
11573 Select the given repository (a repository name). Possible values include:
11575 @item @code{opam}, the default opam repository,
11576 @item @code{coq} or @code{coq-released}, the stable repository for coq packages,
11577 @item @code{coq-core-dev}, the repository that contains development versions of coq,
11578 @item @code{coq-extra-dev}, the repository that contains development versions
11585 Import metadata for a Go module using
11586 @uref{https://proxy.golang.org, proxy.golang.org}.
11589 guix import go gopkg.in/yaml.v2
11592 It is possible to use a package specification with a @code{@@VERSION}
11593 suffix to import a specific version.
11595 Additional options include:
11600 Traverse the dependency graph of the given upstream package recursively
11601 and generate package expressions for all those packages that are not yet
11603 @item --pin-versions
11604 When using this option, the importer preserves the exact versions of the
11605 Go modules dependencies instead of using their latest available
11606 versions. This can be useful when attempting to import packages that
11607 recursively depend on former versions of themselves to build. When
11608 using this mode, the symbol of the package is made by appending the
11609 version to its name, so that multiple versions of the same package can
11615 Import metadata for @uref{https://wiki.call-cc.org/eggs, CHICKEN eggs}.
11616 The information is taken from @file{PACKAGE.egg} files found in the
11617 @uref{git://code.call-cc.org/eggs-5-latest, eggs-5-latest} Git
11618 repository. However, it does not provide all the information that we
11619 need, there is no ``description'' field, and the licenses used are not
11620 always precise (BSD is often used instead of BSD-N).
11623 guix import egg sourcehut
11626 Additional options include:
11630 Traverse the dependency graph of the given upstream package recursively
11631 and generate package expressions for all those packages that are not yet
11636 The structure of the @command{guix import} code is modular. It would be
11637 useful to have more importers for other package formats, and your help
11638 is welcome here (@pxref{Contributing}).
11640 @node Invoking guix refresh
11641 @section Invoking @command{guix refresh}
11643 @cindex @command {guix refresh}
11644 The primary audience of the @command{guix refresh} command is packagers.
11645 As a user, you may be interested in the @option{--with-latest} option,
11646 which can bring you package update superpowers built upon @command{guix
11647 refresh} (@pxref{Package Transformation Options,
11648 @option{--with-latest}}). By default, @command{guix refresh} reports
11649 any packages provided by the distribution that are outdated compared to
11650 the latest upstream version, like this:
11654 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
11655 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
11658 Alternatively, one can specify packages to consider, in which case a
11659 warning is emitted for packages that lack an updater:
11662 $ guix refresh coreutils guile guile-ssh
11663 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
11664 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
11667 @command{guix refresh} browses the upstream repository of each package and determines
11668 the highest version number of the releases therein. The command
11669 knows how to update specific types of packages: GNU packages, ELPA
11670 packages, etc.---see the documentation for @option{--type} below. There
11671 are many packages, though, for which it lacks a method to determine
11672 whether a new upstream release is available. However, the mechanism is
11673 extensible, so feel free to get in touch with us to add a new method!
11678 Consider the packages specified, and all the packages upon which they depend.
11681 $ guix refresh --recursive coreutils
11682 gnu/packages/acl.scm:40:13: acl would be upgraded from 2.2.53 to 2.3.1
11683 gnu/packages/m4.scm:30:12: 1.4.18 is already the latest version of m4
11684 gnu/packages/xml.scm:68:2: warning: no updater for expat
11685 gnu/packages/multiprecision.scm:40:12: 6.1.2 is already the latest version of gmp
11691 Sometimes the upstream name differs from the package name used in Guix,
11692 and @command{guix refresh} needs a little help. Most updaters honor the
11693 @code{upstream-name} property in package definitions, which can be used
11697 (define-public network-manager
11699 (name "network-manager")
11701 (properties '((upstream-name . "NetworkManager")))))
11704 When passed @option{--update}, it modifies distribution source files to
11705 update the version numbers and source tarball hashes of those package
11706 recipes (@pxref{Defining Packages}). This is achieved by downloading
11707 each package's latest source tarball and its associated OpenPGP
11708 signature, authenticating the downloaded tarball against its signature
11709 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
11710 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
11713 key used to sign the tarball is missing from the user's keyring, an
11714 attempt is made to automatically retrieve it from a public key server;
11715 when this is successful, the key is added to the user's keyring; otherwise,
11716 @command{guix refresh} reports an error.
11718 The following options are supported:
11722 @item --expression=@var{expr}
11723 @itemx -e @var{expr}
11724 Consider the package @var{expr} evaluates to.
11726 This is useful to precisely refer to a package, as in this example:
11729 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
11732 This command lists the dependents of the ``final'' libc (essentially all
11737 Update distribution source files (package recipes) in place. This is
11738 usually run from a checkout of the Guix source tree (@pxref{Running
11739 Guix Before It Is Installed}):
11742 $ ./pre-inst-env guix refresh -s non-core -u
11745 @xref{Defining Packages}, for more information on package definitions.
11747 @item --select=[@var{subset}]
11748 @itemx -s @var{subset}
11749 Select all the packages in @var{subset}, one of @code{core} or
11752 The @code{core} subset refers to all the packages at the core of the
11753 distribution---i.e., packages that are used to build ``everything
11754 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
11755 changing one of these packages in the distribution entails a rebuild of
11756 all the others. Thus, such updates are an inconvenience to users in
11757 terms of build time or bandwidth used to achieve the upgrade.
11759 The @code{non-core} subset refers to the remaining packages. It is
11760 typically useful in cases where an update of the core packages would be
11763 @item --manifest=@var{file}
11764 @itemx -m @var{file}
11765 Select all the packages from the manifest in @var{file}. This is useful to
11766 check if any packages of the user manifest can be updated.
11768 @item --type=@var{updater}
11769 @itemx -t @var{updater}
11770 Select only packages handled by @var{updater} (may be a comma-separated
11771 list of updaters). Currently, @var{updater} may be one of:
11775 the updater for GNU packages;
11777 the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
11779 the updater for packages hosted at @uref{https://sourceforge.net, SourceForge};
11781 the updater for GNOME packages;
11783 the updater for KDE packages;
11785 the updater for X.org packages;
11787 the updater for packages hosted on kernel.org;
11789 the updater for @uref{https://wiki.call-cc.org/eggs/, Egg} packages;
11791 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
11793 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
11795 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
11797 the updater for @uref{https://www.cpan.org/, CPAN} packages;
11799 the updater for @uref{https://pypi.python.org, PyPI} packages.
11801 the updater for @uref{https://rubygems.org, RubyGems} packages.
11803 the updater for @uref{https://github.com, GitHub} packages.
11805 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
11807 the updater for @uref{https://www.stackage.org, Stackage} packages.
11809 the updater for @uref{https://crates.io, Crates} packages.
11811 the updater for @uref{https://launchpad.net, Launchpad} packages.
11813 a generic updater that crawls the HTML page where the source tarball of
11814 the package is hosted, when applicable.
11817 For instance, the following command only checks for updates of Emacs
11818 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
11821 $ guix refresh --type=elpa,cran
11822 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
11823 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
11826 @item --list-updaters
11828 List available updaters and exit (see @option{--type} above).
11830 For each updater, display the fraction of packages it covers; at the
11831 end, display the fraction of packages covered by all these updaters.
11834 In addition, @command{guix refresh} can be passed one or more package
11835 names, as in this example:
11838 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
11842 The command above specifically updates the @code{emacs} and
11843 @code{idutils} packages. The @option{--select} option would have no
11844 effect in this case. You might also want to update definitions that
11845 correspond to the packages installed in your profile:
11848 $ ./pre-inst-env guix refresh -u \
11849 $(guix package --list-installed | cut -f1)
11852 When considering whether to upgrade a package, it is sometimes
11853 convenient to know which packages would be affected by the upgrade and
11854 should be checked for compatibility. For this the following option may
11855 be used when passing @command{guix refresh} one or more package names:
11859 @item --list-dependent
11861 List top-level dependent packages that would need to be rebuilt as a
11862 result of upgrading one or more packages.
11864 @xref{Invoking guix graph, the @code{reverse-package} type of
11865 @command{guix graph}}, for information on how to visualize the list of
11866 dependents of a package.
11870 Be aware that the @option{--list-dependent} option only
11871 @emph{approximates} the rebuilds that would be required as a result of
11872 an upgrade. More rebuilds might be required under some circumstances.
11875 $ guix refresh --list-dependent flex
11876 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
11877 hop@@2.4.0 emacs-geiser@@0.13 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
11880 The command above lists a set of packages that could be built to check
11881 for compatibility with an upgraded @code{flex} package.
11885 @item --list-transitive
11886 List all the packages which one or more packages depend upon.
11889 $ guix refresh --list-transitive flex
11890 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
11891 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{}
11896 The command above lists a set of packages which, when changed, would cause
11897 @code{flex} to be rebuilt.
11899 The following options can be used to customize GnuPG operation:
11903 @item --gpg=@var{command}
11904 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
11905 for in @code{$PATH}.
11907 @item --keyring=@var{file}
11908 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
11909 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
11910 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
11911 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
11912 information on a tool to manipulate keybox files).
11914 When this option is omitted, @command{guix refresh} uses
11915 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
11916 signing keys. OpenPGP signatures are checked against keys from this keyring;
11917 missing keys are downloaded to this keyring as well (see
11918 @option{--key-download} below).
11920 You can export keys from your default GPG keyring into a keybox file using
11921 commands like this one:
11924 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
11927 Likewise, you can fetch keys to a specific keybox file like this:
11930 gpg --no-default-keyring --keyring mykeyring.kbx \
11931 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
11934 @xref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
11935 Privacy Guard}, for more information on GPG's @option{--keyring} option.
11937 @item --key-download=@var{policy}
11938 Handle missing OpenPGP keys according to @var{policy}, which may be one
11943 Always download missing OpenPGP keys from the key server, and add them
11944 to the user's GnuPG keyring.
11947 Never try to download missing OpenPGP keys. Instead just bail out.
11950 When a package signed with an unknown OpenPGP key is encountered, ask
11951 the user whether to download it or not. This is the default behavior.
11954 @item --key-server=@var{host}
11955 Use @var{host} as the OpenPGP key server when importing a public key.
11957 @item --load-path=@var{directory}
11958 Add @var{directory} to the front of the package module search path
11959 (@pxref{Package Modules}).
11961 This allows users to define their own packages and make them visible to
11962 the command-line tools.
11966 The @code{github} updater uses the
11967 @uref{https://developer.github.com/v3/, GitHub API} to query for new
11968 releases. When used repeatedly e.g.@: when refreshing all packages,
11969 GitHub will eventually refuse to answer any further API requests. By
11970 default 60 API requests per hour are allowed, and a full refresh on all
11971 GitHub packages in Guix requires more than this. Authentication with
11972 GitHub through the use of an API token alleviates these limits. To use
11973 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
11974 token procured from @uref{https://github.com/settings/tokens} or
11978 @node Invoking guix lint
11979 @section Invoking @command{guix lint}
11981 @cindex @command{guix lint}
11982 @cindex package, checking for errors
11983 The @command{guix lint} command is meant to help package developers avoid
11984 common errors and use a consistent style. It runs a number of checks on
11985 a given set of packages in order to find common mistakes in their
11986 definitions. Available @dfn{checkers} include (see
11987 @option{--list-checkers} for a complete list):
11992 Validate certain typographical and stylistic rules about package
11993 descriptions and synopses.
11995 @item inputs-should-be-native
11996 Identify inputs that should most likely be native inputs.
12002 @itemx source-file-name
12003 Probe @code{home-page} and @code{source} URLs and report those that are
12004 invalid. Suggest a @code{mirror://} URL when applicable. If the
12005 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
12006 URL@. Check that the source file name is meaningful, e.g.@: is not just a
12007 version number or ``git-checkout'', without a declared @code{file-name}
12008 (@pxref{origin Reference}).
12010 @item source-unstable-tarball
12011 Parse the @code{source} URL to determine if a tarball from GitHub is
12012 autogenerated or if it is a release tarball. Unfortunately GitHub's
12013 autogenerated tarballs are sometimes regenerated.
12016 Check that the derivation of the given packages can be successfully
12017 computed for all the supported systems (@pxref{Derivations}).
12019 @item profile-collisions
12020 Check whether installing the given packages in a profile would lead to
12021 collisions. Collisions occur when several packages with the same name
12022 but a different version or a different store file name are propagated.
12023 @xref{package Reference, @code{propagated-inputs}}, for more information
12024 on propagated inputs.
12027 @cindex Software Heritage, source code archive
12028 @cindex archival of source code, Software Heritage
12029 Checks whether the package's source code is archived at
12030 @uref{https://www.softwareheritage.org, Software Heritage}.
12032 When the source code that is not archived comes from a version-control system
12033 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
12034 ``save'' request so that it eventually archives it. This ensures that the
12035 source will remain available in the long term, and that Guix can fall back to
12036 Software Heritage should the source code disappear from its original host.
12037 The status of recent ``save'' requests can be
12038 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
12040 When source code is a tarball obtained with @code{url-fetch}, simply print a
12041 message when it is not archived. As of this writing, Software Heritage does
12042 not allow requests to save arbitrary tarballs; we are working on ways to
12043 ensure that non-VCS source code is also archived.
12046 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
12047 request rate per IP address}. When the limit is reached, @command{guix lint}
12048 prints a message and the @code{archival} checker stops doing anything until
12049 that limit has been reset.
12052 @cindex security vulnerabilities
12053 @cindex CVE, Common Vulnerabilities and Exposures
12054 Report known vulnerabilities found in the Common Vulnerabilities and
12055 Exposures (CVE) databases of the current and past year
12056 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
12059 To view information about a particular vulnerability, visit pages such as:
12063 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
12065 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
12069 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
12070 @code{CVE-2015-7554}.
12072 Package developers can specify in package recipes the
12073 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
12074 name and version of the package when they differ from the name or version
12075 that Guix uses, as in this example:
12081 ;; CPE calls this package "grub2".
12082 (properties '((cpe-name . "grub2")
12083 (cpe-version . "2.3"))))
12086 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
12087 Some entries in the CVE database do not specify which version of a
12088 package they apply to, and would thus ``stick around'' forever. Package
12089 developers who found CVE alerts and verified they can be ignored can
12090 declare them as in this example:
12096 ;; These CVEs no longer apply and can be safely ignored.
12097 (properties `((lint-hidden-cve . ("CVE-2011-0433"
12100 "CVE-2011-5244")))))
12104 Warn about obvious source code formatting issues: trailing white space,
12105 use of tabulations, etc.
12108 The general syntax is:
12111 guix lint @var{options} @var{package}@dots{}
12114 If no package is given on the command line, then all packages are checked.
12115 The @var{options} may be zero or more of the following:
12118 @item --list-checkers
12120 List and describe all the available checkers that will be run on packages
12125 Only enable the checkers specified in a comma-separated list using the
12126 names returned by @option{--list-checkers}.
12130 Only disable the checkers specified in a comma-separated list using the
12131 names returned by @option{--list-checkers}.
12135 Only enable the checkers that do not depend on Internet access.
12137 @item --load-path=@var{directory}
12138 @itemx -L @var{directory}
12139 Add @var{directory} to the front of the package module search path
12140 (@pxref{Package Modules}).
12142 This allows users to define their own packages and make them visible to
12143 the command-line tools.
12147 @node Invoking guix size
12148 @section Invoking @command{guix size}
12151 @cindex package size
12153 @cindex @command{guix size}
12154 The @command{guix size} command helps package developers profile the
12155 disk usage of packages. It is easy to overlook the impact of an
12156 additional dependency added to a package, or the impact of using a
12157 single output for a package that could easily be split (@pxref{Packages
12158 with Multiple Outputs}). Such are the typical issues that
12159 @command{guix size} can highlight.
12161 The command can be passed one or more package specifications
12162 such as @code{gcc@@4.8}
12163 or @code{guile:debug}, or a file name in the store. Consider this
12167 $ guix size coreutils
12168 store item total self
12169 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
12170 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
12171 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
12172 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
12173 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
12174 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
12175 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
12176 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
12181 The store items listed here constitute the @dfn{transitive closure} of
12182 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
12183 would be returned by:
12186 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
12189 Here the output shows three columns next to store items. The first column,
12190 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
12191 the store item---that is, its own size plus the size of all its
12192 dependencies. The next column, labeled ``self'', shows the size of the
12193 item itself. The last column shows the ratio of the size of the item
12194 itself to the space occupied by all the items listed here.
12196 In this example, we see that the closure of Coreutils weighs in at
12197 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
12198 libraries. (That libc and GCC's libraries represent a large fraction of
12199 the closure is not a problem @i{per se} because they are always available
12200 on the system anyway.)
12202 Since the command also accepts store file names, assessing the size of
12203 a build result is straightforward:
12206 guix size $(guix system build config.scm)
12209 When the package(s) passed to @command{guix size} are available in the
12210 store@footnote{More precisely, @command{guix size} looks for the
12211 @emph{ungrafted} variant of the given package(s), as returned by
12212 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
12213 for information on grafts.}, @command{guix size} queries the daemon to determine its
12214 dependencies, and measures its size in the store, similar to @command{du
12215 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
12218 When the given packages are @emph{not} in the store, @command{guix size}
12219 reports information based on the available substitutes
12220 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
12221 store items that are not even on disk, only available remotely.
12223 You can also specify several package names:
12226 $ guix size coreutils grep sed bash
12227 store item total self
12228 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
12229 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
12230 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
12231 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
12237 In this example we see that the combination of the four packages takes
12238 102.3@tie{}MiB in total, which is much less than the sum of each closure
12239 since they have a lot of dependencies in common.
12241 When looking at the profile returned by @command{guix size}, you may
12242 find yourself wondering why a given package shows up in the profile at
12243 all. To understand it, you can use @command{guix graph --path -t
12244 references} to display the shortest path between the two packages
12245 (@pxref{Invoking guix graph}).
12247 The available options are:
12251 @item --substitute-urls=@var{urls}
12252 Use substitute information from @var{urls}.
12253 @xref{client-substitute-urls, the same option for @code{guix build}}.
12255 @item --sort=@var{key}
12256 Sort lines according to @var{key}, one of the following options:
12260 the size of each item (the default);
12262 the total size of the item's closure.
12265 @item --map-file=@var{file}
12266 Write a graphical map of disk usage in PNG format to @var{file}.
12268 For the example above, the map looks like this:
12270 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
12271 produced by @command{guix size}}
12273 This option requires that
12274 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
12275 installed and visible in Guile's module search path. When that is not
12276 the case, @command{guix size} fails as it tries to load it.
12278 @item --system=@var{system}
12279 @itemx -s @var{system}
12280 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
12282 @item --load-path=@var{directory}
12283 @itemx -L @var{directory}
12284 Add @var{directory} to the front of the package module search path
12285 (@pxref{Package Modules}).
12287 This allows users to define their own packages and make them visible to
12288 the command-line tools.
12291 @node Invoking guix graph
12292 @section Invoking @command{guix graph}
12295 @cindex @command{guix graph}
12296 @cindex package dependencies
12297 Packages and their dependencies form a @dfn{graph}, specifically a
12298 directed acyclic graph (DAG). It can quickly become difficult to have a
12299 mental model of the package DAG, so the @command{guix graph} command
12300 provides a visual representation of the DAG@. By default,
12301 @command{guix graph} emits a DAG representation in the input format of
12302 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
12303 directly to the @command{dot} command of Graphviz. It can also emit an
12304 HTML page with embedded JavaScript code to display a ``chord diagram''
12305 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
12306 emit Cypher queries to construct a graph in a graph database supporting
12307 the @uref{https://www.opencypher.org/, openCypher} query language. With
12308 @option{--path}, it simply displays the shortest path between two
12309 packages. The general syntax is:
12312 guix graph @var{options} @var{package}@dots{}
12315 For example, the following command generates a PDF file representing the
12316 package DAG for the GNU@tie{}Core Utilities, showing its build-time
12320 guix graph coreutils | dot -Tpdf > dag.pdf
12323 The output looks like this:
12325 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
12327 Nice little graph, no?
12329 You may find it more pleasant to navigate the graph interactively with
12330 @command{xdot} (from the @code{xdot} package):
12333 guix graph coreutils | xdot -
12336 But there is more than one graph! The one above is concise: it is the
12337 graph of package objects, omitting implicit inputs such as GCC, libc,
12338 grep, etc. It is often useful to have such a concise graph, but
12339 sometimes one may want to see more details. @command{guix graph} supports
12340 several types of graphs, allowing you to choose the level of detail:
12344 This is the default type used in the example above. It shows the DAG of
12345 package objects, excluding implicit dependencies. It is concise, but
12346 filters out many details.
12348 @item reverse-package
12349 This shows the @emph{reverse} DAG of packages. For example:
12352 guix graph --type=reverse-package ocaml
12355 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
12356 you are also interested in cases where OCaml is an implicit dependency, see
12357 @code{reverse-bag} below).
12359 Note that for core packages this can yield huge graphs. If all you want
12360 is to know the number of packages that depend on a given package, use
12361 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
12362 @option{--list-dependent}}).
12365 This is the package DAG, @emph{including} implicit inputs.
12367 For instance, the following command:
12370 guix graph --type=bag-emerged coreutils
12373 ...@: yields this bigger graph:
12375 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
12377 At the bottom of the graph, we see all the implicit inputs of
12378 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
12380 Now, note that the dependencies of these implicit inputs---that is, the
12381 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
12382 here, for conciseness.
12385 Similar to @code{bag-emerged}, but this time including all the bootstrap
12388 @item bag-with-origins
12389 Similar to @code{bag}, but also showing origins and their dependencies.
12392 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
12393 it also takes implicit dependencies into account. For example:
12396 guix graph -t reverse-bag dune
12400 ...@: yields the graph of all packages that depend on Dune, directly or
12401 indirectly. Since Dune is an @emph{implicit} dependency of many packages
12402 @i{via} @code{dune-build-system}, this shows a large number of packages,
12403 whereas @code{reverse-package} would show very few if any.
12406 This is the most detailed representation: It shows the DAG of
12407 derivations (@pxref{Derivations}) and plain store items. Compared to
12408 the above representation, many additional nodes are visible, including
12409 build scripts, patches, Guile modules, etc.
12411 For this type of graph, it is also possible to pass a @file{.drv} file
12412 name instead of a package name, as in:
12415 guix graph -t derivation $(guix system build -d my-config.scm)
12419 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
12420 For example, the following command shows the graph for the package
12421 module that defines the @code{guile} package:
12424 guix graph -t module guile | xdot -
12428 All the types above correspond to @emph{build-time dependencies}. The
12429 following graph type represents the @emph{run-time dependencies}:
12433 This is the graph of @dfn{references} of a package output, as returned
12434 by @command{guix gc --references} (@pxref{Invoking guix gc}).
12436 If the given package output is not available in the store, @command{guix
12437 graph} attempts to obtain dependency information from substitutes.
12439 Here you can also pass a store file name instead of a package name. For
12440 example, the command below produces the reference graph of your profile
12441 (which can be big!):
12444 guix graph -t references $(readlink -f ~/.guix-profile)
12448 This is the graph of the @dfn{referrers} of a store item, as returned by
12449 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
12451 This relies exclusively on local information from your store. For
12452 instance, let us suppose that the current Inkscape is available in 10
12453 profiles on your machine; @command{guix graph -t referrers inkscape}
12454 will show a graph rooted at Inkscape and with those 10 profiles linked
12457 It can help determine what is preventing a store item from being garbage
12462 @cindex shortest path, between packages
12463 Often, the graph of the package you are interested in does not fit on
12464 your screen, and anyway all you want to know is @emph{why} that package
12465 actually depends on some seemingly unrelated package. The
12466 @option{--path} option instructs @command{guix graph} to display the
12467 shortest path between two packages (or derivations, or store items,
12471 $ guix graph --path emacs libunistring
12474 libunistring@@0.9.10
12475 $ guix graph --path -t derivation emacs libunistring
12476 /gnu/store/@dots{}-emacs-26.3.drv
12477 /gnu/store/@dots{}-mailutils-3.9.drv
12478 /gnu/store/@dots{}-libunistring-0.9.10.drv
12479 $ guix graph --path -t references emacs libunistring
12480 /gnu/store/@dots{}-emacs-26.3
12481 /gnu/store/@dots{}-libidn2-2.2.0
12482 /gnu/store/@dots{}-libunistring-0.9.10
12485 The available options are the following:
12488 @item --type=@var{type}
12489 @itemx -t @var{type}
12490 Produce a graph output of @var{type}, where @var{type} must be one of
12491 the values listed above.
12494 List the supported graph types.
12496 @item --backend=@var{backend}
12497 @itemx -b @var{backend}
12498 Produce a graph using the selected @var{backend}.
12500 @item --list-backends
12501 List the supported graph backends.
12503 Currently, the available backends are Graphviz and d3.js.
12506 Display the shortest path between two nodes of the type specified by
12507 @option{--type}. The example below shows the shortest path between
12508 @code{libreoffice} and @code{llvm} according to the references of
12509 @code{libreoffice}:
12512 $ guix graph --path -t references libreoffice llvm
12513 /gnu/store/@dots{}-libreoffice-6.4.2.2
12514 /gnu/store/@dots{}-libepoxy-1.5.4
12515 /gnu/store/@dots{}-mesa-19.3.4
12516 /gnu/store/@dots{}-llvm-9.0.1
12519 @item --expression=@var{expr}
12520 @itemx -e @var{expr}
12521 Consider the package @var{expr} evaluates to.
12523 This is useful to precisely refer to a package, as in this example:
12526 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
12529 @item --system=@var{system}
12530 @itemx -s @var{system}
12531 Display the graph for @var{system}---e.g., @code{i686-linux}.
12533 The package dependency graph is largely architecture-independent, but there
12534 are some architecture-dependent bits that this option allows you to visualize.
12536 @item --load-path=@var{directory}
12537 @itemx -L @var{directory}
12538 Add @var{directory} to the front of the package module search path
12539 (@pxref{Package Modules}).
12541 This allows users to define their own packages and make them visible to
12542 the command-line tools.
12545 On top of that, @command{guix graph} supports all the usual package
12546 transformation options (@pxref{Package Transformation Options}). This
12547 makes it easy to view the effect of a graph-rewriting transformation
12548 such as @option{--with-input}. For example, the command below outputs
12549 the graph of @code{git} once @code{openssl} has been replaced by
12550 @code{libressl} everywhere in the graph:
12553 guix graph git --with-input=openssl=libressl
12556 So many possibilities, so much fun!
12558 @node Invoking guix publish
12559 @section Invoking @command{guix publish}
12561 @cindex @command{guix publish}
12562 The purpose of @command{guix publish} is to enable users to easily share
12563 their store with others, who can then use it as a substitute server
12564 (@pxref{Substitutes}).
12566 When @command{guix publish} runs, it spawns an HTTP server which allows
12567 anyone with network access to obtain substitutes from it. This means
12568 that any machine running Guix can also act as if it were a build farm,
12569 since the HTTP interface is compatible with Cuirass, the software behind
12570 the @code{@value{SUBSTITUTE-SERVER-1}} build farm.
12572 For security, each substitute is signed, allowing recipients to check
12573 their authenticity and integrity (@pxref{Substitutes}). Because
12574 @command{guix publish} uses the signing key of the system, which is only
12575 readable by the system administrator, it must be started as root; the
12576 @option{--user} option makes it drop root privileges early on.
12578 The signing key pair must be generated before @command{guix publish} is
12579 launched, using @command{guix archive --generate-key} (@pxref{Invoking
12582 When the @option{--advertise} option is passed, the server advertises
12583 its availability on the local network using multicast DNS (mDNS) and DNS
12584 service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
12585 guile-avahi, Using Avahi in Guile Scheme Programs}).
12587 The general syntax is:
12590 guix publish @var{options}@dots{}
12593 Running @command{guix publish} without any additional arguments will
12594 spawn an HTTP server on port 8080:
12600 Once a publishing server has been authorized, the daemon may download
12601 substitutes from it. @xref{Getting Substitutes from Other Servers}.
12603 By default, @command{guix publish} compresses archives on the fly as it
12604 serves them. This ``on-the-fly'' mode is convenient in that it requires
12605 no setup and is immediately available. However, when serving lots of
12606 clients, we recommend using the @option{--cache} option, which enables
12607 caching of the archives before they are sent to clients---see below for
12608 details. The @command{guix weather} command provides a handy way to
12609 check what a server provides (@pxref{Invoking guix weather}).
12611 As a bonus, @command{guix publish} also serves as a content-addressed
12612 mirror for source files referenced in @code{origin} records
12613 (@pxref{origin Reference}). For instance, assuming @command{guix
12614 publish} is running on @code{example.org}, the following URL returns the
12615 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
12616 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
12619 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
12622 Obviously, these URLs only work for files that are in the store; in
12623 other cases, they return 404 (``Not Found'').
12625 @cindex build logs, publication
12626 Build logs are available from @code{/log} URLs like:
12629 http://example.org/log/gwspk@dots{}-guile-2.2.3
12633 When @command{guix-daemon} is configured to save compressed build logs,
12634 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
12635 URLs return the compressed log as-is, with an appropriate
12636 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
12637 running @command{guix-daemon} with @option{--log-compression=gzip} since
12638 Web browsers can automatically decompress it, which is not the case with
12641 The following options are available:
12644 @item --port=@var{port}
12645 @itemx -p @var{port}
12646 Listen for HTTP requests on @var{port}.
12648 @item --listen=@var{host}
12649 Listen on the network interface for @var{host}. The default is to
12650 accept connections from any interface.
12652 @item --user=@var{user}
12653 @itemx -u @var{user}
12654 Change privileges to @var{user} as soon as possible---i.e., once the
12655 server socket is open and the signing key has been read.
12657 @item --compression[=@var{method}[:@var{level}]]
12658 @itemx -C [@var{method}[:@var{level}]]
12659 Compress data using the given @var{method} and @var{level}. @var{method} is
12660 one of @code{lzip}, @code{zstd}, and @code{gzip}; when @var{method} is
12661 omitted, @code{gzip} is used.
12663 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
12664 to different compression levels: 1 is the fastest, and 9 is the best
12665 (CPU-intensive). The default is 3.
12667 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a
12668 small increase in CPU usage; see
12669 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip
12670 Web page}. However, @code{lzip} achieves low decompression throughput
12671 (on the order of 50@tie{}MiB/s on modern hardware), which can be a
12672 bottleneck for someone who downloads over a fast network connection.
12674 The compression ratio of @code{zstd} is between that of @code{lzip} and
12675 that of @code{gzip}; its main advantage is a
12676 @uref{https://facebook.github.io/zstd/,high decompression speed}.
12678 Unless @option{--cache} is used, compression occurs on the fly and
12679 the compressed streams are not
12680 cached. Thus, to reduce load on the machine that runs @command{guix
12681 publish}, it may be a good idea to choose a low compression level, to
12682 run @command{guix publish} behind a caching proxy, or to use
12683 @option{--cache}. Using @option{--cache} has the advantage that it
12684 allows @command{guix publish} to add @code{Content-Length} HTTP header
12687 This option can be repeated, in which case every substitute gets compressed
12688 using all the selected methods, and all of them are advertised. This is
12689 useful when users may not support all the compression methods: they can select
12690 the one they support.
12692 @item --cache=@var{directory}
12693 @itemx -c @var{directory}
12694 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
12695 and only serve archives that are in cache.
12697 When this option is omitted, archives and meta-data are created
12698 on-the-fly. This can reduce the available bandwidth, especially when
12699 compression is enabled, since this may become CPU-bound. Another
12700 drawback of the default mode is that the length of archives is not known
12701 in advance, so @command{guix publish} does not add a
12702 @code{Content-Length} HTTP header to its responses, which in turn
12703 prevents clients from knowing the amount of data being downloaded.
12705 Conversely, when @option{--cache} is used, the first request for a store
12706 item (@i{via} a @code{.narinfo} URL) triggers a
12707 background process to @dfn{bake} the archive---computing its
12708 @code{.narinfo} and compressing the archive, if needed. Once the
12709 archive is cached in @var{directory}, subsequent requests succeed and
12710 are served directly from the cache, which guarantees that clients get
12711 the best possible bandwidth.
12713 That first @code{.narinfo} request nonetheless returns 200, provided the
12714 requested store item is ``small enough'', below the cache bypass
12715 threshold---see @option{--cache-bypass-threshold} below. That way,
12716 clients do not have to wait until the archive is baked. For larger
12717 store items, the first @code{.narinfo} request returns 404, meaning that
12718 clients have to wait until the archive is baked.
12720 The ``baking'' process is performed by worker threads. By default, one
12721 thread per CPU core is created, but this can be customized. See
12722 @option{--workers} below.
12724 When @option{--ttl} is used, cached entries are automatically deleted
12725 when they have expired.
12727 @item --workers=@var{N}
12728 When @option{--cache} is used, request the allocation of @var{N} worker
12729 threads to ``bake'' archives.
12731 @item --ttl=@var{ttl}
12732 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
12733 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
12734 days, @code{1m} means 1 month, and so on.
12736 This allows the user's Guix to keep substitute information in cache for
12737 @var{ttl}. However, note that @code{guix publish} does not itself
12738 guarantee that the store items it provides will indeed remain available
12739 for as long as @var{ttl}.
12741 Additionally, when @option{--cache} is used, cached entries that have
12742 not been accessed for @var{ttl} and that no longer have a corresponding
12743 item in the store, may be deleted.
12745 @item --negative-ttl=@var{ttl}
12746 Similarly produce @code{Cache-Control} HTTP headers to advertise the
12747 time-to-live (TTL) of @emph{negative} lookups---missing store items, for
12748 which the HTTP 404 code is returned. By default, no negative TTL is
12751 This parameter can help adjust server load and substitute latency by
12752 instructing cooperating clients to be more or less patient when a store
12755 @item --cache-bypass-threshold=@var{size}
12756 When used in conjunction with @option{--cache}, store items smaller than
12757 @var{size} are immediately available, even when they are not yet in
12758 cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
12759 for megabytes and so on. The default is @code{10M}.
12761 ``Cache bypass'' allows you to reduce the publication delay for clients
12762 at the expense of possibly additional I/O and CPU use on the server
12763 side: depending on the client access patterns, those store items can end
12764 up being baked several times until a copy is available in cache.
12766 Increasing the threshold may be useful for sites that have few users, or
12767 to guarantee that users get substitutes even for store items that are
12770 @item --nar-path=@var{path}
12771 Use @var{path} as the prefix for the URLs of ``nar'' files
12772 (@pxref{Invoking guix archive, normalized archives}).
12774 By default, nars are served at a URL such as
12775 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
12776 change the @code{/nar} part to @var{path}.
12778 @item --public-key=@var{file}
12779 @itemx --private-key=@var{file}
12780 Use the specific @var{file}s as the public/private key pair used to sign
12781 the store items being published.
12783 The files must correspond to the same key pair (the private key is used
12784 for signing and the public key is merely advertised in the signature
12785 metadata). They must contain keys in the canonical s-expression format
12786 as produced by @command{guix archive --generate-key} (@pxref{Invoking
12787 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
12788 @file{/etc/guix/signing-key.sec} are used.
12790 @item --repl[=@var{port}]
12791 @itemx -r [@var{port}]
12792 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
12793 Reference Manual}) on @var{port} (37146 by default). This is used
12794 primarily for debugging a running @command{guix publish} server.
12797 Enabling @command{guix publish} on Guix System is a one-liner: just
12798 instantiate a @code{guix-publish-service-type} service in the @code{services} field
12799 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
12800 @code{guix-publish-service-type}}).
12802 If you are instead running Guix on a ``foreign distro'', follow these
12807 If your host distro uses the systemd init system:
12810 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
12811 /etc/systemd/system/
12812 # systemctl start guix-publish && systemctl enable guix-publish
12816 If your host distro uses the Upstart init system:
12819 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
12820 # start guix-publish
12824 Otherwise, proceed similarly with your distro's init system.
12827 @node Invoking guix challenge
12828 @section Invoking @command{guix challenge}
12830 @cindex reproducible builds
12831 @cindex verifiable builds
12832 @cindex @command{guix challenge}
12834 Do the binaries provided by this server really correspond to the source
12835 code it claims to build? Is a package build process deterministic?
12836 These are the questions the @command{guix challenge} command attempts to
12839 The former is obviously an important question: Before using a substitute
12840 server (@pxref{Substitutes}), one had better @emph{verify} that it
12841 provides the right binaries, and thus @emph{challenge} it. The latter
12842 is what enables the former: If package builds are deterministic, then
12843 independent builds of the package should yield the exact same result,
12844 bit for bit; if a server provides a binary different from the one
12845 obtained locally, it may be either corrupt or malicious.
12847 We know that the hash that shows up in @file{/gnu/store} file names is
12848 the hash of all the inputs of the process that built the file or
12849 directory---compilers, libraries, build scripts,
12850 etc. (@pxref{Introduction}). Assuming deterministic build processes,
12851 one store file name should map to exactly one build output.
12852 @command{guix challenge} checks whether there is, indeed, a single
12853 mapping by comparing the build outputs of several independent builds of
12854 any given store item.
12856 The command output looks like this:
12859 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org"
12860 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER-1}'... 100.0%
12861 updating list of substitutes from 'https://guix.example.org'... 100.0%
12862 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
12863 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
12864 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
12865 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
12867 /lib/libcrypto.so.1.1
12870 /gnu/store/@dots{}-git-2.5.0 contents differ:
12871 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
12872 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
12873 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
12875 /libexec/git-core/git-fsck
12877 /gnu/store/@dots{}-pius-2.1.1 contents differ:
12878 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
12879 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
12880 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
12882 /share/man/man1/pius.1.gz
12886 6,406 store items were analyzed:
12887 - 4,749 (74.1%) were identical
12888 - 525 (8.2%) differed
12889 - 1,132 (17.7%) were inconclusive
12893 In this example, @command{guix challenge} first scans the store to
12894 determine the set of locally-built derivations---as opposed to store
12895 items that were downloaded from a substitute server---and then queries
12896 all the substitute servers. It then reports those store items for which
12897 the servers obtained a result different from the local build.
12899 @cindex non-determinism, in package builds
12900 As an example, @code{guix.example.org} always gets a different answer.
12901 Conversely, @code{@value{SUBSTITUTE-SERVER-1}} agrees with local builds, except in the
12902 case of Git. This might indicate that the build process of Git is
12903 non-deterministic, meaning that its output varies as a function of
12904 various things that Guix does not fully control, in spite of building
12905 packages in isolated environments (@pxref{Features}). Most common
12906 sources of non-determinism include the addition of timestamps in build
12907 results, the inclusion of random numbers, and directory listings sorted
12908 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
12911 To find out what is wrong with this Git binary, the easiest approach is
12915 guix challenge git \
12916 --diff=diffoscope \
12917 --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org"
12920 This automatically invokes @command{diffoscope}, which displays detailed
12921 information about files that differ.
12923 Alternatively, we can do something along these lines (@pxref{Invoking guix
12927 $ wget -q -O - https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-git-2.5.0 \
12928 | lzip -d | guix archive -x /tmp/git
12929 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
12932 This command shows the difference between the files resulting from the
12933 local build, and the files resulting from the build on
12934 @code{@value{SUBSTITUTE-SERVER-1}} (@pxref{Overview, Comparing and Merging Files,,
12935 diffutils, Comparing and Merging Files}). The @command{diff} command
12936 works great for text files. When binary files differ, a better option
12937 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
12938 visualize differences for all kinds of files.
12940 Once you have done that work, you can tell whether the differences are due
12941 to a non-deterministic build process or to a malicious server. We try
12942 hard to remove sources of non-determinism in packages to make it easier
12943 to verify substitutes, but of course, this is a process that
12944 involves not just Guix, but a large part of the free software community.
12945 In the meantime, @command{guix challenge} is one tool to help address
12948 If you are writing packages for Guix, you are encouraged to check
12949 whether @code{@value{SUBSTITUTE-SERVER-1}} and other substitute servers obtain the
12950 same build result as you did with:
12953 $ guix challenge @var{package}
12957 where @var{package} is a package specification such as
12958 @code{guile@@2.0} or @code{glibc:debug}.
12960 The general syntax is:
12963 guix challenge @var{options} [@var{packages}@dots{}]
12966 When a difference is found between the hash of a locally-built item and
12967 that of a server-provided substitute, or among substitutes provided by
12968 different servers, the command displays it as in the example above and
12969 its exit code is 2 (other non-zero exit codes denote other kinds of
12972 The one option that matters is:
12976 @item --substitute-urls=@var{urls}
12977 Consider @var{urls} the whitespace-separated list of substitute source
12978 URLs to compare to.
12980 @item --diff=@var{mode}
12981 Upon mismatches, show differences according to @var{mode}, one of:
12984 @item @code{simple} (the default)
12985 Show the list of files that differ.
12987 @item @code{diffoscope}
12988 @itemx @var{command}
12989 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
12990 two directories whose contents do not match.
12992 When @var{command} is an absolute file name, run @var{command} instead
12996 Do not show further details about the differences.
12999 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
13000 downloads the store items from the given substitute servers so that it
13005 Show details about matches (identical contents) in addition to
13006 information about mismatches.
13010 @node Invoking guix copy
13011 @section Invoking @command{guix copy}
13013 @cindex copy, of store items, over SSH
13014 @cindex SSH, copy of store items
13015 @cindex sharing store items across machines
13016 @cindex transferring store items across machines
13017 The @command{guix copy} command copies items from the store of one
13018 machine to that of another machine over a secure shell (SSH)
13019 connection@footnote{This command is available only when Guile-SSH was
13020 found. @xref{Requirements}, for details.}. For example, the following
13021 command copies the @code{coreutils} package, the user's profile, and all
13022 their dependencies over to @var{host}, logged in as @var{user}:
13025 guix copy --to=@var{user}@@@var{host} \
13026 coreutils $(readlink -f ~/.guix-profile)
13029 If some of the items to be copied are already present on @var{host},
13030 they are not actually sent.
13032 The command below retrieves @code{libreoffice} and @code{gimp} from
13033 @var{host}, assuming they are available there:
13036 guix copy --from=@var{host} libreoffice gimp
13039 The SSH connection is established using the Guile-SSH client, which is
13040 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
13041 @file{~/.ssh/config}, and uses the SSH agent for authentication.
13043 The key used to sign items that are sent must be accepted by the remote
13044 machine. Likewise, the key used by the remote machine to sign items you
13045 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
13046 own daemon. @xref{Invoking guix archive}, for more information about
13047 store item authentication.
13049 The general syntax is:
13052 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
13055 You must always specify one of the following options:
13058 @item --to=@var{spec}
13059 @itemx --from=@var{spec}
13060 Specify the host to send to or receive from. @var{spec} must be an SSH
13061 spec such as @code{example.org}, @code{charlie@@example.org}, or
13062 @code{charlie@@example.org:2222}.
13065 The @var{items} can be either package names, such as @code{gimp}, or
13066 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
13068 When specifying the name of a package to send, it is first built if
13069 needed, unless @option{--dry-run} was specified. Common build options
13070 are supported (@pxref{Common Build Options}).
13073 @node Invoking guix container
13074 @section Invoking @command{guix container}
13076 @cindex @command{guix container}
13078 As of version @value{VERSION}, this tool is experimental. The interface
13079 is subject to radical change in the future.
13082 The purpose of @command{guix container} is to manipulate processes
13083 running within an isolated environment, commonly known as a
13084 ``container'', typically created by the @command{guix environment}
13085 (@pxref{Invoking guix environment}) and @command{guix system container}
13086 (@pxref{Invoking guix system}) commands.
13088 The general syntax is:
13091 guix container @var{action} @var{options}@dots{}
13094 @var{action} specifies the operation to perform with a container, and
13095 @var{options} specifies the context-specific arguments for the action.
13097 The following actions are available:
13101 Execute a command within the context of a running container.
13106 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
13109 @var{pid} specifies the process ID of the running container.
13110 @var{program} specifies an executable file name within the root file
13111 system of the container. @var{arguments} are the additional options that
13112 will be passed to @var{program}.
13114 The following command launches an interactive login shell inside a
13115 Guix system container, started by @command{guix system container}, and whose
13116 process ID is 9001:
13119 guix container exec 9001 /run/current-system/profile/bin/bash --login
13122 Note that the @var{pid} cannot be the parent process of a container. It
13123 must be PID 1 of the container or one of its child processes.
13127 @node Invoking guix weather
13128 @section Invoking @command{guix weather}
13130 Occasionally you're grumpy because substitutes are lacking and you end
13131 up building packages by yourself (@pxref{Substitutes}). The
13132 @command{guix weather} command reports on substitute availability on the
13133 specified servers so you can have an idea of whether you'll be grumpy
13134 today. It can sometimes be useful info as a user, but it is primarily
13135 useful to people running @command{guix publish} (@pxref{Invoking guix
13138 @cindex statistics, for substitutes
13139 @cindex availability of substitutes
13140 @cindex substitute availability
13141 @cindex weather, substitute availability
13142 Here's a sample run:
13145 $ guix weather --substitute-urls=https://guix.example.org
13146 computing 5,872 package derivations for x86_64-linux...
13147 looking for 6,128 store items on https://guix.example.org..
13148 updating list of substitutes from 'https://guix.example.org'... 100.0%
13149 https://guix.example.org
13150 43.4% substitutes available (2,658 out of 6,128)
13151 7,032.5 MiB of nars (compressed)
13152 19,824.2 MiB on disk (uncompressed)
13153 0.030 seconds per request (182.9 seconds in total)
13154 33.5 requests per second
13156 9.8% (342 out of 3,470) of the missing items are queued
13158 x86_64-linux: 518 (59.7%)
13159 i686-linux: 221 (25.5%)
13160 aarch64-linux: 128 (14.8%)
13161 build rate: 23.41 builds per hour
13162 x86_64-linux: 11.16 builds per hour
13163 i686-linux: 6.03 builds per hour
13164 aarch64-linux: 6.41 builds per hour
13167 @cindex continuous integration, statistics
13168 As you can see, it reports the fraction of all the packages for which
13169 substitutes are available on the server---regardless of whether
13170 substitutes are enabled, and regardless of whether this server's signing
13171 key is authorized. It also reports the size of the compressed archives
13172 (``nars'') provided by the server, the size the corresponding store
13173 items occupy in the store (assuming deduplication is turned off), and
13174 the server's throughput. The second part gives continuous integration
13175 (CI) statistics, if the server supports it. In addition, using the
13176 @option{--coverage} option, @command{guix weather} can list ``important''
13177 package substitutes missing on the server (see below).
13179 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
13180 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
13181 challenge}, it ignores signatures on those substitutes, which is
13182 innocuous since the command only gathers statistics and cannot install
13185 The general syntax is:
13188 guix weather @var{options}@dots{} [@var{packages}@dots{}]
13191 When @var{packages} is omitted, @command{guix weather} checks the availability
13192 of substitutes for @emph{all} the packages, or for those specified with
13193 @option{--manifest}; otherwise it only considers the specified packages. It
13194 is also possible to query specific system types with @option{--system}.
13195 @command{guix weather} exits with a non-zero code when the fraction of
13196 available substitutes is below 100%.
13198 The available options are listed below.
13201 @item --substitute-urls=@var{urls}
13202 @var{urls} is the space-separated list of substitute server URLs to
13203 query. When this option is omitted, the default set of substitute
13204 servers is queried.
13206 @item --system=@var{system}
13207 @itemx -s @var{system}
13208 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
13209 option can be repeated, in which case @command{guix weather} will query
13210 substitutes for several system types.
13212 @item --manifest=@var{file}
13213 Instead of querying substitutes for all the packages, only ask for those
13214 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
13215 with the @code{-m} option of @command{guix package} (@pxref{Invoking
13218 This option can be repeated several times, in which case the manifests
13221 @item --coverage[=@var{count}]
13222 @itemx -c [@var{count}]
13223 Report on substitute coverage for packages: list packages with at least
13224 @var{count} dependents (zero by default) for which substitutes are
13225 unavailable. Dependent packages themselves are not listed: if @var{b} depends
13226 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
13227 @var{b} usually lacks substitutes as well. The result looks like this:
13230 $ guix weather --substitute-urls=@value{SUBSTITUTE-URLS} -c 10
13231 computing 8,983 package derivations for x86_64-linux...
13232 looking for 9,343 store items on @value{SUBSTITUTE-URLS}...
13233 updating substitutes from '@value{SUBSTITUTE-URLS}'... 100.0%
13234 @value{SUBSTITUTE-URLS}
13235 64.7% substitutes available (6,047 out of 9,343)
13237 2502 packages are missing from '@value{SUBSTITUTE-URLS}' for 'x86_64-linux', among which:
13238 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
13239 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
13240 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
13244 What this example shows is that @code{kcoreaddons} and presumably the 58
13245 packages that depend on it have no substitutes at
13246 @code{@value{SUBSTITUTE-SERVER-1}}; likewise for @code{qgpgme} and the 46
13247 packages that depend on it.
13249 If you are a Guix developer, or if you are taking care of this build farm,
13250 you'll probably want to have a closer look at these packages: they may simply
13253 @item --display-missing
13254 Display the list of store items for which substitutes are missing.
13257 @node Invoking guix processes
13258 @section Invoking @command{guix processes}
13260 The @command{guix processes} command can be useful to developers and system
13261 administrators, especially on multi-user machines and on build farms: it lists
13262 the current sessions (connections to the daemon), as well as information about
13263 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
13264 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
13265 listed.}. Here's an example of the information it returns:
13268 $ sudo guix processes
13271 ClientCommand: guix environment --ad-hoc python
13275 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
13279 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
13280 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
13281 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
13282 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
13284 ChildCommand: guix offload x86_64-linux 7200 1 28800
13286 ChildCommand: guix offload x86_64-linux 7200 1 28800
13288 ChildCommand: guix offload x86_64-linux 7200 1 28800
13291 In this example we see that @command{guix-daemon} has three clients:
13292 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
13293 integration tool; their process identifier (PID) is given by the
13294 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
13295 @command{guix-daemon} sub-process of this particular session.
13297 The @code{LockHeld} fields show which store items are currently locked
13298 by this session, which corresponds to store items being built or
13299 substituted (the @code{LockHeld} field is not displayed when
13300 @command{guix processes} is not running as root). Last, by looking at
13301 the @code{ChildPID} and @code{ChildCommand} fields, we understand that
13302 these three builds are being offloaded (@pxref{Daemon Offload Setup}).
13304 The output is in Recutils format so we can use the handy @command{recsel}
13305 command to select sessions of interest (@pxref{Selection Expressions,,,
13306 recutils, GNU recutils manual}). As an example, the command shows the command
13307 line and PID of the client that triggered the build of a Perl package:
13310 $ sudo guix processes | \
13311 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
13313 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
13316 Additional options are listed below.
13319 @item --format=@var{format}
13320 @itemx -f @var{format}
13321 Produce output in the specified @var{format}, one of:
13325 The default option. It outputs a set of Session recutils records
13326 that include each @code{ChildProcess} as a field.
13329 Normalize the output records into record sets (@pxref{Record Sets,,,
13330 recutils, GNU recutils manual}). Normalizing into record sets allows
13331 joins across record types. The example below lists the PID of each
13332 @code{ChildProcess} and the associated PID for @code{Session} that
13333 spawned the @code{ChildProcess} where the @code{Session} was started
13334 using @command{guix build}.
13337 $ guix processes --format=normalized | \
13341 -p Session.PID,PID \
13342 -e 'Session.ClientCommand ~ "guix build"'
13355 @node System Configuration
13356 @chapter System Configuration
13358 @cindex system configuration
13359 Guix System supports a consistent whole-system configuration
13360 mechanism. By that we mean that all aspects of the global system
13361 configuration---such as the available system services, timezone and
13362 locale settings, user accounts---are declared in a single place. Such
13363 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
13365 One of the advantages of putting all the system configuration under the
13366 control of Guix is that it supports transactional system upgrades, and
13367 makes it possible to roll back to a previous system instantiation,
13368 should something go wrong with the new one (@pxref{Features}). Another
13369 advantage is that it makes it easy to replicate the exact same configuration
13370 across different machines, or at different points in time, without
13371 having to resort to additional administration tools layered on top of
13372 the own tools of the system.
13373 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
13375 This section describes this mechanism. First we focus on the system
13376 administrator's viewpoint---explaining how the system is configured and
13377 instantiated. Then we show how this mechanism can be extended, for
13378 instance to support new system services.
13381 * Using the Configuration System:: Customizing your GNU system.
13382 * operating-system Reference:: Detail of operating-system declarations.
13383 * File Systems:: Configuring file system mounts.
13384 * Mapped Devices:: Block device extra processing.
13385 * User Accounts:: Specifying user accounts.
13386 * Keyboard Layout:: How the system interprets key strokes.
13387 * Locales:: Language and cultural convention settings.
13388 * Services:: Specifying system services.
13389 * Setuid Programs:: Programs running with root privileges.
13390 * X.509 Certificates:: Authenticating HTTPS servers.
13391 * Name Service Switch:: Configuring libc's name service switch.
13392 * Initial RAM Disk:: Linux-Libre bootstrapping.
13393 * Bootloader Configuration:: Configuring the boot loader.
13394 * Invoking guix system:: Instantiating a system configuration.
13395 * Invoking guix deploy:: Deploying a system configuration to a remote host.
13396 * Running Guix in a VM:: How to run Guix System in a virtual machine.
13397 * Defining Services:: Adding new service definitions.
13400 @node Using the Configuration System
13401 @section Using the Configuration System
13403 The operating system is configured by providing an
13404 @code{operating-system} declaration in a file that can then be passed to
13405 the @command{guix system} command (@pxref{Invoking guix system}). A
13406 simple setup, with the default system services, the default Linux-Libre
13407 kernel, initial RAM disk, and boot loader looks like this:
13409 @findex operating-system
13411 @include os-config-bare-bones.texi
13414 This example should be self-describing. Some of the fields defined
13415 above, such as @code{host-name} and @code{bootloader}, are mandatory.
13416 Others, such as @code{packages} and @code{services}, can be omitted, in
13417 which case they get a default value.
13419 Below we discuss the effect of some of the most important fields
13420 (@pxref{operating-system Reference}, for details about all the available
13421 fields), and how to @dfn{instantiate} the operating system using
13422 @command{guix system}.
13424 @unnumberedsubsec Bootloader
13426 @cindex legacy boot, on Intel machines
13427 @cindex BIOS boot, on Intel machines
13430 The @code{bootloader} field describes the method that will be used to boot
13431 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
13432 mode, as in the example above. However, more recent machines rely instead on
13433 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
13434 the @code{bootloader} field should contain something along these lines:
13437 (bootloader-configuration
13438 (bootloader grub-efi-bootloader)
13439 (target "/boot/efi"))
13442 @xref{Bootloader Configuration}, for more information on the available
13443 configuration options.
13445 @unnumberedsubsec Globally-Visible Packages
13447 @vindex %base-packages
13448 The @code{packages} field lists packages that will be globally visible
13449 on the system, for all user accounts---i.e., in every user's @env{PATH}
13450 environment variable---in addition to the per-user profiles
13451 (@pxref{Invoking guix package}). The @code{%base-packages} variable
13452 provides all the tools one would expect for basic user and administrator
13453 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
13454 the GNU Zile lightweight text editor, @command{find}, @command{grep},
13455 etc. The example above adds GNU@tie{}Screen to those,
13456 taken from the @code{(gnu packages screen)}
13457 module (@pxref{Package Modules}). The
13458 @code{(list package output)} syntax can be used to add a specific output
13462 (use-modules (gnu packages))
13463 (use-modules (gnu packages dns))
13467 (packages (cons (list isc-bind "utils")
13471 @findex specification->package
13472 Referring to packages by variable name, like @code{isc-bind} above, has
13473 the advantage of being unambiguous; it also allows typos and such to be
13474 diagnosed right away as ``unbound variables''. The downside is that one
13475 needs to know which module defines which package, and to augment the
13476 @code{use-package-modules} line accordingly. To avoid that, one can use
13477 the @code{specification->package} procedure of the @code{(gnu packages)}
13478 module, which returns the best package for a given name or name and
13482 (use-modules (gnu packages))
13486 (packages (append (map specification->package
13487 '("tcpdump" "htop" "gnupg@@2.0"))
13491 @unnumberedsubsec System Services
13494 @vindex %base-services
13495 The @code{services} field lists @dfn{system services} to be made
13496 available when the system starts (@pxref{Services}).
13497 The @code{operating-system} declaration above specifies that, in
13498 addition to the basic services, we want the OpenSSH secure shell
13499 daemon listening on port 2222 (@pxref{Networking Services,
13500 @code{openssh-service-type}}). Under the hood,
13501 @code{openssh-service-type} arranges so that @command{sshd} is started with the
13502 right command-line options, possibly with supporting configuration files
13503 generated as needed (@pxref{Defining Services}).
13505 @cindex customization, of services
13506 @findex modify-services
13507 Occasionally, instead of using the base services as is, you will want to
13508 customize them. To do this, use @code{modify-services} (@pxref{Service
13509 Reference, @code{modify-services}}) to modify the list.
13511 For example, suppose you want to modify @code{guix-daemon} and Mingetty
13512 (the console log-in) in the @code{%base-services} list (@pxref{Base
13513 Services, @code{%base-services}}). To do that, you can write the
13514 following in your operating system declaration:
13517 (define %my-services
13518 ;; My very own list of services.
13519 (modify-services %base-services
13520 (guix-service-type config =>
13521 (guix-configuration
13523 ;; Fetch substitutes from example.org.
13525 (list "https://example.org/guix"
13526 "https://ci.guix.gnu.org"))))
13527 (mingetty-service-type config =>
13528 (mingetty-configuration
13530 ;; Automatially log in as "guest".
13531 (auto-login "guest")))))
13535 (services %my-services))
13538 This changes the configuration---i.e., the service parameters---of the
13539 @code{guix-service-type} instance, and that of all the
13540 @code{mingetty-service-type} instances in the @code{%base-services} list.
13541 Observe how this is accomplished: first, we arrange for the original
13542 configuration to be bound to the identifier @code{config} in the
13543 @var{body}, and then we write the @var{body} so that it evaluates to the
13544 desired configuration. In particular, notice how we use @code{inherit}
13545 to create a new configuration which has the same values as the old
13546 configuration, but with a few modifications.
13548 @cindex encrypted disk
13549 The configuration for a typical ``desktop'' usage, with an encrypted
13550 root partition, the X11 display
13551 server, GNOME and Xfce (users can choose which of these desktop
13552 environments to use at the log-in screen by pressing @kbd{F1}), network
13553 management, power management, and more, would look like this:
13556 @include os-config-desktop.texi
13559 A graphical system with a choice of lightweight window managers
13560 instead of full-blown desktop environments would look like this:
13563 @include os-config-lightweight-desktop.texi
13566 This example refers to the @file{/boot/efi} file system by its UUID,
13567 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
13568 as returned by the @command{blkid} command.
13570 @xref{Desktop Services}, for the exact list of services provided by
13571 @code{%desktop-services}. @xref{X.509 Certificates}, for background
13572 information about the @code{nss-certs} package that is used here.
13574 Again, @code{%desktop-services} is just a list of service objects. If
13575 you want to remove services from there, you can do so using the
13576 procedures for list filtering (@pxref{SRFI-1 Filtering and
13577 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
13578 following expression returns a list that contains all the services in
13579 @code{%desktop-services} minus the Avahi service:
13582 (remove (lambda (service)
13583 (eq? (service-kind service) avahi-service-type))
13587 Alternatively, the @code{modify-services} macro can be used:
13590 (modify-services %desktop-services
13591 (delete avahi-service-type))
13595 @unnumberedsubsec Instantiating the System
13597 Assuming the @code{operating-system} declaration
13598 is stored in the @file{my-system-config.scm}
13599 file, the @command{guix system reconfigure my-system-config.scm} command
13600 instantiates that configuration, and makes it the default GRUB boot
13601 entry (@pxref{Invoking guix system}).
13603 The normal way to change the system configuration is by updating this
13604 file and re-running @command{guix system reconfigure}. One should never
13605 have to touch files in @file{/etc} or to run commands that modify the
13606 system state such as @command{useradd} or @command{grub-install}. In
13607 fact, you must avoid that since that would not only void your warranty
13608 but also prevent you from rolling back to previous versions of your
13609 system, should you ever need to.
13611 @cindex roll-back, of the operating system
13612 Speaking of roll-back, each time you run @command{guix system
13613 reconfigure}, a new @dfn{generation} of the system is created---without
13614 modifying or deleting previous generations. Old system generations get
13615 an entry in the bootloader boot menu, allowing you to boot them in case
13616 something went wrong with the latest generation. Reassuring, no? The
13617 @command{guix system list-generations} command lists the system
13618 generations available on disk. It is also possible to roll back the
13619 system via the commands @command{guix system roll-back} and
13620 @command{guix system switch-generation}.
13622 Although the @command{guix system reconfigure} command will not modify
13623 previous generations, you must take care when the current generation is not
13624 the latest (e.g., after invoking @command{guix system roll-back}), since
13625 the operation might overwrite a later generation (@pxref{Invoking guix
13628 @unnumberedsubsec The Programming Interface
13630 At the Scheme level, the bulk of an @code{operating-system} declaration
13631 is instantiated with the following monadic procedure (@pxref{The Store
13634 @deffn {Monadic Procedure} operating-system-derivation os
13635 Return a derivation that builds @var{os}, an @code{operating-system}
13636 object (@pxref{Derivations}).
13638 The output of the derivation is a single directory that refers to all
13639 the packages, configuration files, and other supporting files needed to
13640 instantiate @var{os}.
13643 This procedure is provided by the @code{(gnu system)} module. Along
13644 with @code{(gnu services)} (@pxref{Services}), this module contains the
13645 guts of Guix System. Make sure to visit it!
13648 @node operating-system Reference
13649 @section @code{operating-system} Reference
13651 This section summarizes all the options available in
13652 @code{operating-system} declarations (@pxref{Using the Configuration
13655 @deftp {Data Type} operating-system
13656 This is the data type representing an operating system configuration.
13657 By that, we mean all the global system configuration, not per-user
13658 configuration (@pxref{Using the Configuration System}).
13661 @item @code{kernel} (default: @code{linux-libre})
13662 The package object of the operating system kernel to
13663 use@footnote{Currently only the Linux-libre kernel is fully supported.
13664 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
13665 available when building a virtual machine disk image.}.
13668 @item @code{hurd} (default: @code{#f})
13669 The package object of the Hurd to be started by the kernel. When this
13670 field is set, produce a GNU/Hurd operating system. In that case,
13671 @code{kernel} must also be set to the @code{gnumach} package---the
13672 microkernel the Hurd runs on.
13675 This feature is experimental and only supported for disk images.
13678 @item @code{kernel-loadable-modules} (default: '())
13679 A list of objects (usually packages) to collect loadable kernel modules
13680 from--e.g. @code{(list ddcci-driver-linux)}.
13682 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
13683 List of strings or gexps representing additional arguments to pass on
13684 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
13686 @item @code{bootloader}
13687 The system bootloader configuration object. @xref{Bootloader Configuration}.
13690 This is the label (a string) as it appears in the bootloader's menu entry.
13691 The default label includes the kernel name and version.
13693 @item @code{keyboard-layout} (default: @code{#f})
13694 This field specifies the keyboard layout to use in the console. It can be
13695 either @code{#f}, in which case the default keyboard layout is used (usually
13696 US English), or a @code{<keyboard-layout>} record. @xref{Keyboard Layout},
13697 for more information.
13699 This keyboard layout is in effect as soon as the kernel has booted. For
13700 instance, it is the keyboard layout in effect when you type a passphrase if
13701 your root file system is on a @code{luks-device-mapping} mapped device
13702 (@pxref{Mapped Devices}).
13705 This does @emph{not} specify the keyboard layout used by the bootloader, nor
13706 that used by the graphical display server. @xref{Bootloader Configuration},
13707 for information on how to specify the bootloader's keyboard layout. @xref{X
13708 Window}, for information on how to specify the keyboard layout used by the X
13712 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
13714 @cindex initial RAM disk
13715 The list of Linux kernel modules that need to be available in the
13716 initial RAM disk. @xref{Initial RAM Disk}.
13718 @item @code{initrd} (default: @code{base-initrd})
13719 A procedure that returns an initial RAM disk for the Linux
13720 kernel. This field is provided to support low-level customization and
13721 should rarely be needed for casual use. @xref{Initial RAM Disk}.
13723 @item @code{firmware} (default: @code{%base-firmware})
13725 List of firmware packages loadable by the operating system kernel.
13727 The default includes firmware needed for Atheros- and Broadcom-based
13728 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
13729 respectively). @xref{Hardware Considerations}, for more info on
13730 supported hardware.
13732 @item @code{host-name}
13735 @item @code{hosts-file}
13737 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
13738 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
13739 Reference Manual}). The default is a file with entries for
13740 @code{localhost} and @var{host-name}.
13742 @item @code{mapped-devices} (default: @code{'()})
13743 A list of mapped devices. @xref{Mapped Devices}.
13745 @item @code{file-systems}
13746 A list of file systems. @xref{File Systems}.
13748 @cindex swap devices
13750 @item @code{swap-devices} (default: @code{'()})
13751 A list of UUIDs, file system labels, or strings identifying devices or
13752 files to be used for ``swap
13753 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
13754 Manual}). Here are some examples:
13757 @item (list (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb"))
13758 Use the swap partition with the given UUID@. You can learn the UUID of a
13759 Linux swap partition by running @command{swaplabel @var{device}}, where
13760 @var{device} is the @file{/dev} file name of that partition.
13762 @item (list (file-system-label "swap"))
13763 Use the partition with label @code{swap}. Again, the
13764 @command{swaplabel} command allows you to view and change the label of a
13765 Linux swap partition.
13767 @item (list "/swapfile")
13768 Use the file @file{/swapfile} as swap space.
13770 @item (list "/dev/sda3" "/dev/sdb2")
13771 Use the @file{/dev/sda3} and @file{/dev/sdb2} partitions as swap space.
13772 We recommend referring to swap devices by UUIDs or labels as shown above
13776 It is possible to specify a swap file in a file system on a mapped
13777 device (under @file{/dev/mapper}), provided that the necessary device
13778 mapping and file system are also specified. @xref{Mapped Devices} and
13779 @ref{File Systems}.
13781 @item @code{users} (default: @code{%base-user-accounts})
13782 @itemx @code{groups} (default: @code{%base-groups})
13783 List of user accounts and groups. @xref{User Accounts}.
13785 If the @code{users} list lacks a user account with UID@tie{}0, a
13786 ``root'' account with UID@tie{}0 is automatically added.
13788 @item @code{skeletons} (default: @code{(default-skeletons)})
13789 A list of target file name/file-like object tuples (@pxref{G-Expressions,
13790 file-like objects}). These are the skeleton files that will be added to
13791 the home directory of newly-created user accounts.
13793 For instance, a valid value may look like this:
13796 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
13797 (".guile" ,(plain-file "guile"
13798 "(use-modules (ice-9 readline))
13799 (activate-readline)")))
13802 @item @code{issue} (default: @code{%default-issue})
13803 A string denoting the contents of the @file{/etc/issue} file, which is
13804 displayed when users log in on a text console.
13806 @item @code{packages} (default: @code{%base-packages})
13807 A list of packages to be installed in the global profile, which is accessible
13808 at @file{/run/current-system/profile}. Each element is either a package
13809 variable or a package/output tuple. Here's a simple example of both:
13812 (cons* git ; the default "out" output
13813 (list git "send-email") ; another output of git
13814 %base-packages) ; the default set
13817 The default set includes core utilities and it is good practice to
13818 install non-core utilities in user profiles (@pxref{Invoking guix
13821 @item @code{timezone}
13822 A timezone identifying string---e.g., @code{"Europe/Paris"}.
13824 You can run the @command{tzselect} command to find out which timezone
13825 string corresponds to your region. Choosing an invalid timezone name
13826 causes @command{guix system} to fail.
13828 @item @code{locale} (default: @code{"en_US.utf8"})
13829 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
13830 Library Reference Manual}). @xref{Locales}, for more information.
13832 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
13833 The list of locale definitions to be compiled and that may be used at
13834 run time. @xref{Locales}.
13836 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
13837 The list of GNU@tie{}libc packages whose locale data and tools are used
13838 to build the locale definitions. @xref{Locales}, for compatibility
13839 considerations that justify this option.
13841 @item @code{name-service-switch} (default: @code{%default-nss})
13842 Configuration of the libc name service switch (NSS)---a
13843 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
13846 @item @code{services} (default: @code{%base-services})
13847 A list of service objects denoting system services. @xref{Services}.
13849 @cindex essential services
13850 @item @code{essential-services} (default: ...)
13851 The list of ``essential services''---i.e., things like instances of
13852 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
13853 Reference}), which are derived from the operating system definition itself.
13854 As a user you should @emph{never} need to touch this field.
13856 @item @code{pam-services} (default: @code{(base-pam-services)})
13858 @cindex pluggable authentication modules
13859 Linux @dfn{pluggable authentication module} (PAM) services.
13860 @c FIXME: Add xref to PAM services section.
13862 @item @code{setuid-programs} (default: @code{%setuid-programs})
13863 List of string-valued G-expressions denoting setuid programs.
13864 @xref{Setuid Programs}.
13866 @item @code{sudoers-file} (default: @code{%sudoers-specification})
13867 @cindex sudoers file
13868 The contents of the @file{/etc/sudoers} file as a file-like object
13869 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
13871 This file specifies which users can use the @command{sudo} command, what
13872 they are allowed to do, and what privileges they may gain. The default
13873 is that only @code{root} and members of the @code{wheel} group may use
13878 @deffn {Scheme Syntax} this-operating-system
13879 When used in the @emph{lexical scope} of an operating system field definition,
13880 this identifier resolves to the operating system being defined.
13882 The example below shows how to refer to the operating system being defined in
13883 the definition of the @code{label} field:
13886 (use-modules (gnu) (guix))
13890 (label (package-full-name
13891 (operating-system-kernel this-operating-system))))
13894 It is an error to refer to @code{this-operating-system} outside an operating
13901 @section File Systems
13903 The list of file systems to be mounted is specified in the
13904 @code{file-systems} field of the operating system declaration
13905 (@pxref{Using the Configuration System}). Each file system is declared
13906 using the @code{file-system} form, like this:
13910 (mount-point "/home")
13911 (device "/dev/sda3")
13915 As usual, some of the fields are mandatory---those shown in the example
13916 above---while others can be omitted. These are described below.
13918 @deftp {Data Type} file-system
13919 Objects of this type represent file systems to be mounted. They
13920 contain the following members:
13924 This is a string specifying the type of the file system---e.g.,
13927 @item @code{mount-point}
13928 This designates the place where the file system is to be mounted.
13930 @item @code{device}
13931 This names the ``source'' of the file system. It can be one of three
13932 things: a file system label, a file system UUID, or the name of a
13933 @file{/dev} node. Labels and UUIDs offer a way to refer to file
13934 systems without having to hard-code their actual device
13935 name@footnote{Note that, while it is tempting to use
13936 @file{/dev/disk/by-uuid} and similar device names to achieve the same
13937 result, this is not recommended: These special device nodes are created
13938 by the udev daemon and may be unavailable at the time the device is
13941 @findex file-system-label
13942 File system labels are created using the @code{file-system-label}
13943 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
13944 plain strings. Here's an example of a file system referred to by its
13945 label, as shown by the @command{e2label} command:
13949 (mount-point "/home")
13951 (device (file-system-label "my-home")))
13955 UUIDs are converted from their string representation (as shown by the
13956 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
13957 @code{uuid} form expects 16-byte UUIDs as defined in
13958 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
13959 form of UUID used by the ext2 family of file systems and others, but it
13960 is different from ``UUIDs'' found in FAT file systems, for instance.},
13965 (mount-point "/home")
13967 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
13970 When the source of a file system is a mapped device (@pxref{Mapped
13971 Devices}), its @code{device} field @emph{must} refer to the mapped
13972 device name---e.g., @file{"/dev/mapper/root-partition"}.
13973 This is required so that
13974 the system knows that mounting the file system depends on having the
13975 corresponding device mapping established.
13977 @item @code{flags} (default: @code{'()})
13978 This is a list of symbols denoting mount flags. Recognized flags
13979 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
13980 access to special files), @code{no-suid} (ignore setuid and setgid
13981 bits), @code{no-atime} (do not update file access times),
13982 @code{strict-atime} (update file access time), @code{lazy-time} (only
13983 update time on the in-memory version of the file inode), and
13984 @code{no-exec} (disallow program execution).
13985 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
13986 Manual}, for more information on these flags.
13988 @item @code{options} (default: @code{#f})
13989 This is either @code{#f}, or a string denoting mount options passed to
13990 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
13991 Library Reference Manual}, for details and run @command{man 8 mount} for
13992 options for various file systems. Note that the
13993 @code{file-system-options->alist} and @code{alist->file-system-options}
13994 procedures from @code{(gnu system file-systems)} can be used to convert
13995 file system options given as an association list to the string
13996 representation, and vice-versa.
13998 @item @code{mount?} (default: @code{#t})
13999 This value indicates whether to automatically mount the file system when
14000 the system is brought up. When set to @code{#f}, the file system gets
14001 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
14002 is not automatically mounted.
14004 @item @code{needed-for-boot?} (default: @code{#f})
14005 This Boolean value indicates whether the file system is needed when
14006 booting. If that is true, then the file system is mounted when the
14007 initial RAM disk (initrd) is loaded. This is always the case, for
14008 instance, for the root file system.
14010 @item @code{check?} (default: @code{#t})
14011 This Boolean indicates whether the file system needs to be checked for
14012 errors before being mounted.
14014 @item @code{create-mount-point?} (default: @code{#f})
14015 When true, the mount point is created if it does not exist yet.
14017 @item @code{mount-may-fail?} (default: @code{#f})
14018 When true, this indicates that mounting this file system can fail but
14019 that should not be considered an error. This is useful in unusual
14020 cases; an example of this is @code{efivarfs}, a file system that can
14021 only be mounted on EFI/UEFI systems.
14023 @item @code{dependencies} (default: @code{'()})
14024 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
14025 representing file systems that must be mounted or mapped devices that
14026 must be opened before (and unmounted or closed after) this one.
14028 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
14029 a dependency of @file{/sys/fs/cgroup/cpu} and
14030 @file{/sys/fs/cgroup/memory}.
14032 Another example is a file system that depends on a mapped device, for
14033 example for an encrypted partition (@pxref{Mapped Devices}).
14037 @deffn {Scheme Procedure} file-system-label @var{str}
14038 This procedure returns an opaque file system label from @var{str}, a
14042 (file-system-label "home")
14043 @result{} #<file-system-label "home">
14046 File system labels are used to refer to file systems by label rather
14047 than by device name. See above for examples.
14050 The @code{(gnu system file-systems)} exports the following useful
14053 @defvr {Scheme Variable} %base-file-systems
14054 These are essential file systems that are required on normal systems,
14055 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
14056 below). Operating system declarations should always contain at least
14060 @defvr {Scheme Variable} %pseudo-terminal-file-system
14061 This is the file system to be mounted as @file{/dev/pts}. It supports
14062 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
14063 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
14064 Manual}). Pseudo-terminals are used by terminal emulators such as
14068 @defvr {Scheme Variable} %shared-memory-file-system
14069 This file system is mounted as @file{/dev/shm} and is used to support
14070 memory sharing across processes (@pxref{Memory-mapped I/O,
14071 @code{shm_open},, libc, The GNU C Library Reference Manual}).
14074 @defvr {Scheme Variable} %immutable-store
14075 This file system performs a read-only ``bind mount'' of
14076 @file{/gnu/store}, making it read-only for all the users including
14077 @code{root}. This prevents against accidental modification by software
14078 running as @code{root} or by system administrators.
14080 The daemon itself is still able to write to the store: it remounts it
14081 read-write in its own ``name space.''
14084 @defvr {Scheme Variable} %binary-format-file-system
14085 The @code{binfmt_misc} file system, which allows handling of arbitrary
14086 executable file types to be delegated to user space. This requires the
14087 @code{binfmt.ko} kernel module to be loaded.
14090 @defvr {Scheme Variable} %fuse-control-file-system
14091 The @code{fusectl} file system, which allows unprivileged users to mount
14092 and unmount user-space FUSE file systems. This requires the
14093 @code{fuse.ko} kernel module to be loaded.
14096 The @code{(gnu system uuid)} module provides tools to deal with file
14097 system ``unique identifiers'' (UUIDs).
14099 @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
14100 Return an opaque UUID (unique identifier) object of the given @var{type}
14101 (a symbol) by parsing @var{str} (a string):
14104 (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
14105 @result{} #<<uuid> type: dce bv: @dots{}>
14107 (uuid "1234-ABCD" 'fat)
14108 @result{} #<<uuid> type: fat bv: @dots{}>
14111 @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
14112 @code{ntfs}, or one of the commonly found synonyms for these.
14114 UUIDs are another way to unambiguously refer to file systems in
14115 operating system configuration. See the examples above.
14119 @node Btrfs file system
14120 @subsection Btrfs file system
14122 The Btrfs has special features, such as subvolumes, that merit being
14123 explained in more details. The following section attempts to cover
14124 basic as well as complex uses of a Btrfs file system with the Guix
14127 In its simplest usage, a Btrfs file system can be described, for
14132 (mount-point "/home")
14134 (device (file-system-label "my-home")))
14137 The example below is more complex, as it makes use of a Btrfs
14138 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
14139 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
14140 dependency on @code{mapped-devices}):
14144 (device (file-system-label "my-btrfs-pool"))
14147 (options "subvol=rootfs")
14148 (dependencies mapped-devices))
14151 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
14152 top level during the early boot, and rely on their configuration to
14153 refer to the correct subvolume path within that top level. The
14154 bootloaders operating in this way typically produce their configuration
14155 on a running system where the Btrfs partitions are already mounted and
14156 where the subvolume information is readily available. As an example,
14157 @command{grub-mkconfig}, the configuration generator command shipped
14158 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
14159 path of a subvolume.
14161 The Guix System produces a bootloader configuration using the operating
14162 system configuration as its sole input; it is therefore necessary to
14163 extract the subvolume name on which @file{/gnu/store} lives (if any)
14164 from that operating system configuration. To better illustrate,
14165 consider a subvolume named 'rootfs' which contains the root file system
14166 data. In such situation, the GRUB bootloader would only see the top
14167 level of the root Btrfs partition, e.g.:
14171 ├── rootfs (subvolume directory)
14172 ├── gnu (normal directory)
14173 ├── store (normal directory)
14177 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
14178 of the kernel, initrd binaries and any other files referred to in the
14179 GRUB configuration that must be found during the early boot.
14181 The next example shows a nested hierarchy of subvolumes and
14186 ├── rootfs (subvolume)
14187 ├── gnu (normal directory)
14188 ├── store (subvolume)
14192 This scenario would work without mounting the 'store' subvolume.
14193 Mounting 'rootfs' is sufficient, since the subvolume name matches its
14194 intended mount point in the file system hierarchy. Alternatively, the
14195 'store' subvolume could be referred to by setting the @code{subvol}
14196 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
14198 Finally, a more contrived example of nested subvolumes:
14202 ├── root-snapshots (subvolume)
14203 ├── root-current (subvolume)
14204 ├── guix-store (subvolume)
14208 Here, the 'guix-store' subvolume doesn't match its intended mount point,
14209 so it is necessary to mount it. The subvolume must be fully specified,
14210 by passing its file name to the @code{subvol} option. To illustrate,
14211 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
14212 a file system declaration such as:
14216 (device (file-system-label "btrfs-pool-1"))
14217 (mount-point "/gnu/store")
14219 (options "subvol=root-snapshots/root-current/guix-store,\
14220 compress-force=zstd,space_cache=v2"))
14223 @node Mapped Devices
14224 @section Mapped Devices
14226 @cindex device mapping
14227 @cindex mapped devices
14228 The Linux kernel has a notion of @dfn{device mapping}: a block device,
14229 such as a hard disk partition, can be @dfn{mapped} into another device,
14230 usually in @code{/dev/mapper/},
14231 with additional processing over the data that flows through
14232 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
14233 concept of a ``mapped device'' and that of a file system: both boil down
14234 to @emph{translating} input/output operations made on a file to
14235 operations on its backing store. Thus, the Hurd implements mapped
14236 devices, like file systems, using the generic @dfn{translator} mechanism
14237 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
14238 typical example is encryption device mapping: all writes to the mapped
14239 device are encrypted, and all reads are deciphered, transparently.
14240 Guix extends this notion by considering any device or set of devices that
14241 are @dfn{transformed} in some way to create a new device; for instance,
14242 RAID devices are obtained by @dfn{assembling} several other devices, such
14243 as hard disks or partitions, into a new one that behaves as one partition.
14245 Mapped devices are declared using the @code{mapped-device} form,
14246 defined as follows; for examples, see below.
14248 @deftp {Data Type} mapped-device
14249 Objects of this type represent device mappings that will be made when
14250 the system boots up.
14254 This is either a string specifying the name of the block device to be mapped,
14255 such as @code{"/dev/sda3"}, or a list of such strings when several devices
14256 need to be assembled for creating a new one. In case of LVM this is a
14257 string specifying name of the volume group to be mapped.
14260 This string specifies the name of the resulting mapped device. For
14261 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
14262 specifying @code{"my-partition"} leads to the creation of
14263 the @code{"/dev/mapper/my-partition"} device.
14264 For RAID devices of type @code{raid-device-mapping}, the full device name
14265 such as @code{"/dev/md0"} needs to be given.
14266 LVM logical volumes of type @code{lvm-device-mapping} need to
14267 be specified as @code{"VGNAME-LVNAME"}.
14270 This list of strings specifies names of the resulting mapped devices in case
14271 there are several. The format is identical to @var{target}.
14274 This must be a @code{mapped-device-kind} object, which specifies how
14275 @var{source} is mapped to @var{target}.
14279 @defvr {Scheme Variable} luks-device-mapping
14280 This defines LUKS block device encryption using the @command{cryptsetup}
14281 command from the package with the same name. It relies on the
14282 @code{dm-crypt} Linux kernel module.
14285 @defvr {Scheme Variable} raid-device-mapping
14286 This defines a RAID device, which is assembled using the @code{mdadm}
14287 command from the package with the same name. It requires a Linux kernel
14288 module for the appropriate RAID level to be loaded, such as @code{raid456}
14289 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
14292 @cindex LVM, logical volume manager
14293 @defvr {Scheme Variable} lvm-device-mapping
14294 This defines one or more logical volumes for the Linux
14295 @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
14296 The volume group is activated by the @command{vgchange} command from the
14297 @code{lvm2} package.
14300 @cindex disk encryption
14302 The following example specifies a mapping from @file{/dev/sda3} to
14303 @file{/dev/mapper/home} using LUKS---the
14304 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
14305 standard mechanism for disk encryption.
14306 The @file{/dev/mapper/home}
14307 device can then be used as the @code{device} of a @code{file-system}
14308 declaration (@pxref{File Systems}).
14312 (source "/dev/sda3")
14314 (type luks-device-mapping))
14317 Alternatively, to become independent of device numbering, one may obtain
14318 the LUKS UUID (@dfn{unique identifier}) of the source device by a
14322 cryptsetup luksUUID /dev/sda3
14325 and use it as follows:
14329 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
14331 (type luks-device-mapping))
14334 @cindex swap encryption
14335 It is also desirable to encrypt swap space, since swap space may contain
14336 sensitive data. One way to accomplish that is to use a swap file in a
14337 file system on a device mapped via LUKS encryption. In this way, the
14338 swap file is encrypted because the entire device is encrypted.
14339 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
14341 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
14342 may be declared as follows:
14346 (source (list "/dev/sda1" "/dev/sdb1"))
14347 (target "/dev/md0")
14348 (type raid-device-mapping))
14351 The @file{/dev/md0} device can then be used as the @code{device} of a
14352 @code{file-system} declaration (@pxref{File Systems}).
14353 Note that the RAID level need not be given; it is chosen during the
14354 initial creation and formatting of the RAID device and is determined
14355 automatically later.
14357 LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
14358 be declared as follows:
14363 (targets (list "vg0-alpha" "vg0-beta"))
14364 (type lvm-device-mapping))
14367 Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
14368 then be used as the @code{device} of a @code{file-system} declaration
14369 (@pxref{File Systems}).
14371 @node User Accounts
14372 @section User Accounts
14376 @cindex user accounts
14377 User accounts and groups are entirely managed through the
14378 @code{operating-system} declaration. They are specified with the
14379 @code{user-account} and @code{user-group} forms:
14385 (supplementary-groups '("wheel" ;allow use of sudo, etc.
14386 "audio" ;sound card
14387 "video" ;video devices such as webcams
14388 "cdrom")) ;the good ol' CD-ROM
14389 (comment "Bob's sister"))
14392 Here's a user account that uses a different shell and a custom home
14393 directory (the default would be @file{"/home/bob"}):
14399 (comment "Alice's bro")
14400 (shell (file-append zsh "/bin/zsh"))
14401 (home-directory "/home/robert"))
14404 When booting or upon completion of @command{guix system reconfigure},
14405 the system ensures that only the user accounts and groups specified in
14406 the @code{operating-system} declaration exist, and with the specified
14407 properties. Thus, account or group creations or modifications made by
14408 directly invoking commands such as @command{useradd} are lost upon
14409 reconfiguration or reboot. This ensures that the system remains exactly
14412 @deftp {Data Type} user-account
14413 Objects of this type represent user accounts. The following members may
14418 The name of the user account.
14422 This is the name (a string) or identifier (a number) of the user group
14423 this account belongs to.
14425 @item @code{supplementary-groups} (default: @code{'()})
14426 Optionally, this can be defined as a list of group names that this
14427 account belongs to.
14429 @item @code{uid} (default: @code{#f})
14430 This is the user ID for this account (a number), or @code{#f}. In the
14431 latter case, a number is automatically chosen by the system when the
14432 account is created.
14434 @item @code{comment} (default: @code{""})
14435 A comment about the account, such as the account owner's full name.
14437 @item @code{home-directory}
14438 This is the name of the home directory for the account.
14440 @item @code{create-home-directory?} (default: @code{#t})
14441 Indicates whether the home directory of this account should be created
14442 if it does not exist yet.
14444 @item @code{shell} (default: Bash)
14445 This is a G-expression denoting the file name of a program to be used as
14446 the shell (@pxref{G-Expressions}). For example, you would refer to the
14447 Bash executable like this:
14450 (file-append bash "/bin/bash")
14454 ... and to the Zsh executable like that:
14457 (file-append zsh "/bin/zsh")
14460 @item @code{system?} (default: @code{#f})
14461 This Boolean value indicates whether the account is a ``system''
14462 account. System accounts are sometimes treated specially; for instance,
14463 graphical login managers do not list them.
14465 @anchor{user-account-password}
14466 @cindex password, for user accounts
14467 @item @code{password} (default: @code{#f})
14468 You would normally leave this field to @code{#f}, initialize user
14469 passwords as @code{root} with the @command{passwd} command, and then let
14470 users change it with @command{passwd}. Passwords set with
14471 @command{passwd} are of course preserved across reboot and
14474 If you @emph{do} want to set an initial password for an account, then
14475 this field must contain the encrypted password, as a string. You can use the
14476 @code{crypt} procedure for this purpose:
14483 ;; Specify a SHA-512-hashed initial password.
14484 (password (crypt "InitialPassword!" "$6$abc")))
14488 The hash of this initial password will be available in a file in
14489 @file{/gnu/store}, readable by all the users, so this method must be used with
14493 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
14494 more information on password encryption, and @ref{Encryption,,, guile, GNU
14495 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
14501 User group declarations are even simpler:
14504 (user-group (name "students"))
14507 @deftp {Data Type} user-group
14508 This type is for, well, user groups. There are just a few fields:
14512 The name of the group.
14514 @item @code{id} (default: @code{#f})
14515 The group identifier (a number). If @code{#f}, a new number is
14516 automatically allocated when the group is created.
14518 @item @code{system?} (default: @code{#f})
14519 This Boolean value indicates whether the group is a ``system'' group.
14520 System groups have low numerical IDs.
14522 @item @code{password} (default: @code{#f})
14523 What, user groups can have a password? Well, apparently yes. Unless
14524 @code{#f}, this field specifies the password of the group.
14529 For convenience, a variable lists all the basic user groups one may
14532 @defvr {Scheme Variable} %base-groups
14533 This is the list of basic user groups that users and/or packages expect
14534 to be present on the system. This includes groups such as ``root'',
14535 ``wheel'', and ``users'', as well as groups used to control access to
14536 specific devices such as ``audio'', ``disk'', and ``cdrom''.
14539 @defvr {Scheme Variable} %base-user-accounts
14540 This is the list of basic system accounts that programs may expect to
14541 find on a GNU/Linux system, such as the ``nobody'' account.
14543 Note that the ``root'' account is not included here. It is a
14544 special-case and is automatically added whether or not it is specified.
14547 @node Keyboard Layout
14548 @section Keyboard Layout
14550 @cindex keyboard layout
14552 To specify what each key of your keyboard does, you need to tell the operating
14553 system what @dfn{keyboard layout} you want to use. The default, when nothing
14554 is specified, is the US English QWERTY layout for 105-key PC keyboards.
14555 However, German speakers will usually prefer the German QWERTZ layout, French
14556 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
14557 or bépo, and they might even want to further customize the effect of some of
14558 the keys. This section explains how to get that done.
14560 @cindex keyboard layout, definition
14561 There are three components that will want to know about your keyboard layout:
14565 The @emph{bootloader} may want to know what keyboard layout you want to use
14566 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
14567 you want, for instance, to make sure that you can type the passphrase of your
14568 encrypted root partition using the right layout.
14571 The @emph{operating system kernel}, Linux, will need that so that the console
14572 is properly configured (@pxref{operating-system Reference,
14573 @code{keyboard-layout}}).
14576 The @emph{graphical display server}, usually Xorg, also has its own idea of
14577 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
14580 Guix allows you to configure all three separately but, fortunately, it allows
14581 you to share the same keyboard layout for all three components.
14583 @cindex XKB, keyboard layouts
14584 Keyboard layouts are represented by records created by the
14585 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
14586 the X Keyboard extension (XKB), each layout has four attributes: a name (often
14587 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
14588 optional variant name, an optional keyboard model name, and a possibly empty
14589 list of additional options. In most cases the layout name is all you care
14592 @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
14593 [#:model] [#:options '()]
14594 Return a new keyboard layout with the given @var{name} and @var{variant}.
14596 @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
14597 string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
14598 @code{xkeyboard-config} package for valid options.
14601 Here are a few examples:
14604 ;; The German QWERTZ layout. Here we assume a standard
14605 ;; "pc105" keyboard model.
14606 (keyboard-layout "de")
14608 ;; The bépo variant of the French layout.
14609 (keyboard-layout "fr" "bepo")
14611 ;; The Catalan layout.
14612 (keyboard-layout "es" "cat")
14614 ;; Arabic layout with "Alt-Shift" to switch to US layout.
14615 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
14617 ;; The Latin American Spanish layout. In addition, the
14618 ;; "Caps Lock" key is used as an additional "Ctrl" key,
14619 ;; and the "Menu" key is used as a "Compose" key to enter
14620 ;; accented letters.
14621 (keyboard-layout "latam"
14622 #:options '("ctrl:nocaps" "compose:menu"))
14624 ;; The Russian layout for a ThinkPad keyboard.
14625 (keyboard-layout "ru" #:model "thinkpad")
14627 ;; The "US international" layout, which is the US layout plus
14628 ;; dead keys to enter accented characters. This is for an
14629 ;; Apple MacBook keyboard.
14630 (keyboard-layout "us" "intl" #:model "macbook78")
14633 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
14634 for a complete list of supported layouts, variants, and models.
14636 @cindex keyboard layout, configuration
14637 Let's say you want your system to use the Turkish keyboard layout throughout
14638 your system---bootloader, console, and Xorg. Here's what your system
14639 configuration would look like:
14641 @findex set-xorg-configuration
14643 ;; Using the Turkish layout for the bootloader, the console,
14648 (keyboard-layout (keyboard-layout "tr")) ;for the console
14649 (bootloader (bootloader-configuration
14650 (bootloader grub-efi-bootloader)
14651 (target "/boot/efi")
14652 (keyboard-layout keyboard-layout))) ;for GRUB
14653 (services (cons (set-xorg-configuration
14654 (xorg-configuration ;for Xorg
14655 (keyboard-layout keyboard-layout)))
14656 %desktop-services)))
14659 In the example above, for GRUB and for Xorg, we just refer to the
14660 @code{keyboard-layout} field defined above, but we could just as well refer to
14661 a different layout. The @code{set-xorg-configuration} procedure communicates
14662 the desired Xorg configuration to the graphical log-in manager, by default
14665 We've discussed how to specify the @emph{default} keyboard layout of your
14666 system when it starts, but you can also adjust it at run time:
14670 If you're using GNOME, its settings panel has a ``Region & Language'' entry
14671 where you can select one or more keyboard layouts.
14674 Under Xorg, the @command{setxkbmap} command (from the same-named package)
14675 allows you to change the current layout. For example, this is how you would
14676 change the layout to US Dvorak:
14679 setxkbmap us dvorak
14683 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
14684 console. However, note that @code{loadkeys} does @emph{not} use the XKB
14685 keyboard layout categorization described above. The command below loads the
14686 French bépo layout:
14697 A @dfn{locale} defines cultural conventions for a particular language
14698 and region of the world (@pxref{Locales,,, libc, The GNU C Library
14699 Reference Manual}). Each locale has a name that typically has the form
14700 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
14701 @code{fr_LU.utf8} designates the locale for the French language, with
14702 cultural conventions from Luxembourg, and using the UTF-8 encoding.
14704 @cindex locale definition
14705 Usually, you will want to specify the default locale for the machine
14706 using the @code{locale} field of the @code{operating-system} declaration
14707 (@pxref{operating-system Reference, @code{locale}}).
14709 The selected locale is automatically added to the @dfn{locale
14710 definitions} known to the system if needed, with its codeset inferred
14711 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
14712 @code{UTF-8} codeset. Additional locale definitions can be specified in
14713 the @code{locale-definitions} slot of @code{operating-system}---this is
14714 useful, for instance, if the codeset could not be inferred from the
14715 locale name. The default set of locale definitions includes some widely
14716 used locales, but not all the available locales, in order to save space.
14718 For instance, to add the North Frisian locale for Germany, the value of
14722 (cons (locale-definition
14723 (name "fy_DE.utf8") (source "fy_DE"))
14724 %default-locale-definitions)
14727 Likewise, to save space, one might want @code{locale-definitions} to
14728 list only the locales that are actually used, as in:
14731 (list (locale-definition
14732 (name "ja_JP.eucjp") (source "ja_JP")
14733 (charset "EUC-JP")))
14737 The compiled locale definitions are available at
14738 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
14739 version, which is the default location where the GNU@tie{}libc provided
14740 by Guix looks for locale data. This can be overridden using the
14741 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
14742 @env{LOCPATH} and locale packages}).
14744 The @code{locale-definition} form is provided by the @code{(gnu system
14745 locale)} module. Details are given below.
14747 @deftp {Data Type} locale-definition
14748 This is the data type of a locale definition.
14753 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
14754 Reference Manual}, for more information on locale names.
14756 @item @code{source}
14757 The name of the source for that locale. This is typically the
14758 @code{@var{language}_@var{territory}} part of the locale name.
14760 @item @code{charset} (default: @code{"UTF-8"})
14761 The ``character set'' or ``code set'' for that locale,
14762 @uref{https://www.iana.org/assignments/character-sets, as defined by
14768 @defvr {Scheme Variable} %default-locale-definitions
14769 A list of commonly used UTF-8 locales, used as the default
14770 value of the @code{locale-definitions} field of @code{operating-system}
14773 @cindex locale name
14774 @cindex normalized codeset in locale names
14775 These locale definitions use the @dfn{normalized codeset} for the part
14776 that follows the dot in the name (@pxref{Using gettextized software,
14777 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
14778 instance it has @code{uk_UA.utf8} but @emph{not}, say,
14779 @code{uk_UA.UTF-8}.
14782 @subsection Locale Data Compatibility Considerations
14784 @cindex incompatibility, of locale data
14785 @code{operating-system} declarations provide a @code{locale-libcs} field
14786 to specify the GNU@tie{}libc packages that are used to compile locale
14787 declarations (@pxref{operating-system Reference}). ``Why would I
14788 care?'', you may ask. Well, it turns out that the binary format of
14789 locale data is occasionally incompatible from one libc version to
14792 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
14793 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
14794 For instance, a program linked against libc version 2.21 is unable to
14795 read locale data produced with libc 2.22; worse, that program
14796 @emph{aborts} instead of simply ignoring the incompatible locale
14797 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
14798 the incompatible locale data, which is already an improvement.}.
14799 Similarly, a program linked against libc 2.22 can read most, but not
14800 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
14801 data is incompatible); thus calls to @code{setlocale} may fail, but
14802 programs will not abort.
14804 The ``problem'' with Guix is that users have a lot of freedom: They can
14805 choose whether and when to upgrade software in their profiles, and might
14806 be using a libc version different from the one the system administrator
14807 used to build the system-wide locale data.
14809 Fortunately, unprivileged users can also install their own locale data
14810 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
14811 @env{GUIX_LOCPATH} and locale packages}).
14813 Still, it is best if the system-wide locale data at
14814 @file{/run/current-system/locale} is built for all the libc versions
14815 actually in use on the system, so that all the programs can access
14816 it---this is especially crucial on a multi-user system. To do that, the
14817 administrator can specify several libc packages in the
14818 @code{locale-libcs} field of @code{operating-system}:
14821 (use-package-modules base)
14825 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
14828 This example would lead to a system containing locale definitions for
14829 both libc 2.21 and the current version of libc in
14830 @file{/run/current-system/locale}.
14836 @cindex system services
14837 An important part of preparing an @code{operating-system} declaration is
14838 listing @dfn{system services} and their configuration (@pxref{Using the
14839 Configuration System}). System services are typically daemons launched
14840 when the system boots, or other actions needed at that time---e.g.,
14841 configuring network access.
14843 Guix has a broad definition of ``service'' (@pxref{Service
14844 Composition}), but many services are managed by the GNU@tie{}Shepherd
14845 (@pxref{Shepherd Services}). On a running system, the @command{herd}
14846 command allows you to list the available services, show their status,
14847 start and stop them, or do other specific operations (@pxref{Jump
14848 Start,,, shepherd, The GNU Shepherd Manual}). For example:
14854 The above command, run as @code{root}, lists the currently defined
14855 services. The @command{herd doc} command shows a synopsis of the given
14856 service and its associated actions:
14860 Run libc's name service cache daemon (nscd).
14862 # herd doc nscd action invalidate
14863 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
14866 The @command{start}, @command{stop}, and @command{restart} sub-commands
14867 have the effect you would expect. For instance, the commands below stop
14868 the nscd service and restart the Xorg display server:
14872 Service nscd has been stopped.
14873 # herd restart xorg-server
14874 Service xorg-server has been stopped.
14875 Service xorg-server has been started.
14878 The following sections document the available services, starting with
14879 the core services, that may be used in an @code{operating-system}
14883 * Base Services:: Essential system services.
14884 * Scheduled Job Execution:: The mcron service.
14885 * Log Rotation:: The rottlog service.
14886 * Networking Services:: Network setup, SSH daemon, etc.
14887 * Unattended Upgrades:: Automated system upgrades.
14888 * X Window:: Graphical display.
14889 * Printing Services:: Local and remote printer support.
14890 * Desktop Services:: D-Bus and desktop services.
14891 * Sound Services:: ALSA and Pulseaudio services.
14892 * Database Services:: SQL databases, key-value stores, etc.
14893 * Mail Services:: IMAP, POP3, SMTP, and all that.
14894 * Messaging Services:: Messaging services.
14895 * Telephony Services:: Telephony services.
14896 * File-Sharing Services:: File-sharing services.
14897 * Monitoring Services:: Monitoring services.
14898 * Kerberos Services:: Kerberos services.
14899 * LDAP Services:: LDAP services.
14900 * Web Services:: Web servers.
14901 * Certificate Services:: TLS certificates via Let's Encrypt.
14902 * DNS Services:: DNS daemons.
14903 * VPN Services:: VPN daemons.
14904 * Network File System:: NFS related services.
14905 * Continuous Integration:: Cuirass and Laminar services.
14906 * Power Management Services:: Extending battery life.
14907 * Audio Services:: The MPD.
14908 * Virtualization Services:: Virtualization services.
14909 * Version Control Services:: Providing remote access to Git repositories.
14910 * Game Services:: Game servers.
14911 * PAM Mount Service:: Service to mount volumes when logging in.
14912 * Guix Services:: Services relating specifically to Guix.
14913 * Linux Services:: Services tied to the Linux kernel.
14914 * Hurd Services:: Services specific for a Hurd System.
14915 * Miscellaneous Services:: Other services.
14918 @node Base Services
14919 @subsection Base Services
14921 The @code{(gnu services base)} module provides definitions for the basic
14922 services that one expects from the system. The services exported by
14923 this module are listed below.
14925 @defvr {Scheme Variable} %base-services
14926 This variable contains a list of basic services (@pxref{Service Types
14927 and Services}, for more information on service objects) one would
14928 expect from the system: a login service (mingetty) on each tty, syslogd,
14929 the libc name service cache daemon (nscd), the udev device manager, and
14932 This is the default value of the @code{services} field of
14933 @code{operating-system} declarations. Usually, when customizing a
14934 system, you will want to append services to @code{%base-services}, like
14938 (append (list (service avahi-service-type)
14939 (service openssh-service-type))
14944 @defvr {Scheme Variable} special-files-service-type
14945 This is the service that sets up ``special files'' such as
14946 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
14948 The value associated with @code{special-files-service-type} services
14949 must be a list of tuples where the first element is the ``special file''
14950 and the second element is its target. By default it is:
14952 @cindex @file{/bin/sh}
14953 @cindex @file{sh}, in @file{/bin}
14955 `(("/bin/sh" ,(file-append bash "/bin/sh")))
14958 @cindex @file{/usr/bin/env}
14959 @cindex @file{env}, in @file{/usr/bin}
14960 If you want to add, say, @code{/usr/bin/env} to your system, you can
14964 `(("/bin/sh" ,(file-append bash "/bin/sh"))
14965 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
14968 Since this is part of @code{%base-services}, you can use
14969 @code{modify-services} to customize the set of special files
14970 (@pxref{Service Reference, @code{modify-services}}). But the simple way
14971 to add a special file is @i{via} the @code{extra-special-file} procedure
14975 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
14976 Use @var{target} as the ``special file'' @var{file}.
14978 For example, adding the following lines to the @code{services} field of
14979 your operating system declaration leads to a @file{/usr/bin/env}
14983 (extra-special-file "/usr/bin/env"
14984 (file-append coreutils "/bin/env"))
14988 @deffn {Scheme Procedure} host-name-service @var{name}
14989 Return a service that sets the host name to @var{name}.
14992 @defvr {Scheme Variable} console-font-service-type
14993 Install the given fonts on the specified ttys (fonts are per
14994 virtual console on the kernel Linux). The value of this service is a list of
14995 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
14996 package or any valid argument to @command{setfont}, as in this example:
14999 `(("tty1" . "LatGrkCyr-8x16")
15000 ("tty2" . ,(file-append
15002 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
15003 ("tty3" . ,(file-append
15005 "/share/consolefonts/ter-132n"))) ; for HDPI
15009 @deffn {Scheme Procedure} login-service @var{config}
15010 Return a service to run login according to @var{config}, a
15011 @code{<login-configuration>} object, which specifies the message of the day,
15012 among other things.
15015 @deftp {Data Type} login-configuration
15016 This is the data type representing the configuration of login.
15021 @cindex message of the day
15022 A file-like object containing the ``message of the day''.
15024 @item @code{allow-empty-passwords?} (default: @code{#t})
15025 Allow empty passwords by default so that first-time users can log in when
15026 the 'root' account has just been created.
15031 @deffn {Scheme Procedure} mingetty-service @var{config}
15032 Return a service to run mingetty according to @var{config}, a
15033 @code{<mingetty-configuration>} object, which specifies the tty to run, among
15037 @deftp {Data Type} mingetty-configuration
15038 This is the data type representing the configuration of Mingetty, which
15039 provides the default implementation of virtual console log-in.
15044 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
15046 @item @code{auto-login} (default: @code{#f})
15047 When true, this field must be a string denoting the user name under
15048 which the system automatically logs in. When it is @code{#f}, a
15049 user name and password must be entered to log in.
15051 @item @code{login-program} (default: @code{#f})
15052 This must be either @code{#f}, in which case the default log-in program
15053 is used (@command{login} from the Shadow tool suite), or a gexp denoting
15054 the name of the log-in program.
15056 @item @code{login-pause?} (default: @code{#f})
15057 When set to @code{#t} in conjunction with @var{auto-login}, the user
15058 will have to press a key before the log-in shell is launched.
15060 @item @code{clear-on-logout?} (default: @code{#t})
15061 When set to @code{#t}, the screen will be cleared after logout.
15063 @item @code{mingetty} (default: @var{mingetty})
15064 The Mingetty package to use.
15069 @deffn {Scheme Procedure} agetty-service @var{config}
15070 Return a service to run agetty according to @var{config}, an
15071 @code{<agetty-configuration>} object, which specifies the tty to run,
15072 among other things.
15075 @deftp {Data Type} agetty-configuration
15076 This is the data type representing the configuration of agetty, which
15077 implements virtual and serial console log-in. See the @code{agetty(8)}
15078 man page for more information.
15083 The name of the console this agetty runs on, as a string---e.g.,
15084 @code{"ttyS0"}. This argument is optional, it will default to
15085 a reasonable default serial port used by the kernel Linux.
15087 For this, if there is a value for an option @code{agetty.tty} in the kernel
15088 command line, agetty will extract the device name of the serial port
15089 from it and use that.
15091 If not and if there is a value for an option @code{console} with a tty in
15092 the Linux command line, agetty will extract the device name of the
15093 serial port from it and use that.
15095 In both cases, agetty will leave the other serial device settings
15096 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
15099 @item @code{baud-rate} (default: @code{#f})
15100 A string containing a comma-separated list of one or more baud rates, in
15103 @item @code{term} (default: @code{#f})
15104 A string containing the value used for the @env{TERM} environment
15107 @item @code{eight-bits?} (default: @code{#f})
15108 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
15111 @item @code{auto-login} (default: @code{#f})
15112 When passed a login name, as a string, the specified user will be logged
15113 in automatically without prompting for their login name or password.
15115 @item @code{no-reset?} (default: @code{#f})
15116 When @code{#t}, don't reset terminal cflags (control modes).
15118 @item @code{host} (default: @code{#f})
15119 This accepts a string containing the ``login_host'', which will be written
15120 into the @file{/var/run/utmpx} file.
15122 @item @code{remote?} (default: @code{#f})
15123 When set to @code{#t} in conjunction with @var{host}, this will add an
15124 @code{-r} fakehost option to the command line of the login program
15125 specified in @var{login-program}.
15127 @item @code{flow-control?} (default: @code{#f})
15128 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
15130 @item @code{no-issue?} (default: @code{#f})
15131 When set to @code{#t}, the contents of the @file{/etc/issue} file will
15132 not be displayed before presenting the login prompt.
15134 @item @code{init-string} (default: @code{#f})
15135 This accepts a string that will be sent to the tty or modem before
15136 sending anything else. It can be used to initialize a modem.
15138 @item @code{no-clear?} (default: @code{#f})
15139 When set to @code{#t}, agetty will not clear the screen before showing
15142 @item @code{login-program} (default: (file-append shadow "/bin/login"))
15143 This must be either a gexp denoting the name of a log-in program, or
15144 unset, in which case the default value is the @command{login} from the
15147 @item @code{local-line} (default: @code{#f})
15148 Control the CLOCAL line flag. This accepts one of three symbols as
15149 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
15150 the default value chosen by agetty is @code{'auto}.
15152 @item @code{extract-baud?} (default: @code{#f})
15153 When set to @code{#t}, instruct agetty to try to extract the baud rate
15154 from the status messages produced by certain types of modems.
15156 @item @code{skip-login?} (default: @code{#f})
15157 When set to @code{#t}, do not prompt the user for a login name. This
15158 can be used with @var{login-program} field to use non-standard login
15161 @item @code{no-newline?} (default: @code{#f})
15162 When set to @code{#t}, do not print a newline before printing the
15163 @file{/etc/issue} file.
15165 @c Is this dangerous only when used with login-program, or always?
15166 @item @code{login-options} (default: @code{#f})
15167 This option accepts a string containing options that are passed to the
15168 login program. When used with the @var{login-program}, be aware that a
15169 malicious user could try to enter a login name containing embedded
15170 options that could be parsed by the login program.
15172 @item @code{login-pause} (default: @code{#f})
15173 When set to @code{#t}, wait for any key before showing the login prompt.
15174 This can be used in conjunction with @var{auto-login} to save memory by
15175 lazily spawning shells.
15177 @item @code{chroot} (default: @code{#f})
15178 Change root to the specified directory. This option accepts a directory
15181 @item @code{hangup?} (default: @code{#f})
15182 Use the Linux system call @code{vhangup} to do a virtual hangup of the
15183 specified terminal.
15185 @item @code{keep-baud?} (default: @code{#f})
15186 When set to @code{#t}, try to keep the existing baud rate. The baud
15187 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
15190 @item @code{timeout} (default: @code{#f})
15191 When set to an integer value, terminate if no user name could be read
15192 within @var{timeout} seconds.
15194 @item @code{detect-case?} (default: @code{#f})
15195 When set to @code{#t}, turn on support for detecting an uppercase-only
15196 terminal. This setting will detect a login name containing only
15197 uppercase letters as indicating an uppercase-only terminal and turn on
15198 some upper-to-lower case conversions. Note that this will not support
15199 Unicode characters.
15201 @item @code{wait-cr?} (default: @code{#f})
15202 When set to @code{#t}, wait for the user or modem to send a
15203 carriage-return or linefeed character before displaying
15204 @file{/etc/issue} or login prompt. This is typically used with the
15205 @var{init-string} option.
15207 @item @code{no-hints?} (default: @code{#f})
15208 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
15211 @item @code{no-hostname?} (default: @code{#f})
15212 By default, the hostname is printed. When this option is set to
15213 @code{#t}, no hostname will be shown at all.
15215 @item @code{long-hostname?} (default: @code{#f})
15216 By default, the hostname is only printed until the first dot. When this
15217 option is set to @code{#t}, the fully qualified hostname by
15218 @code{gethostname} or @code{getaddrinfo} is shown.
15220 @item @code{erase-characters} (default: @code{#f})
15221 This option accepts a string of additional characters that should be
15222 interpreted as backspace when the user types their login name.
15224 @item @code{kill-characters} (default: @code{#f})
15225 This option accepts a string that should be interpreted to mean ``ignore
15226 all previous characters'' (also called a ``kill'' character) when the user
15227 types their login name.
15229 @item @code{chdir} (default: @code{#f})
15230 This option accepts, as a string, a directory path that will be changed
15233 @item @code{delay} (default: @code{#f})
15234 This options accepts, as an integer, the number of seconds to sleep
15235 before opening the tty and displaying the login prompt.
15237 @item @code{nice} (default: @code{#f})
15238 This option accepts, as an integer, the nice value with which to run the
15239 @command{login} program.
15241 @item @code{extra-options} (default: @code{'()})
15242 This option provides an ``escape hatch'' for the user to provide arbitrary
15243 command-line arguments to @command{agetty} as a list of strings.
15248 @deffn {Scheme Procedure} kmscon-service-type @var{config}
15249 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
15250 according to @var{config}, a @code{<kmscon-configuration>} object, which
15251 specifies the tty to run, among other things.
15254 @deftp {Data Type} kmscon-configuration
15255 This is the data type representing the configuration of Kmscon, which
15256 implements virtual console log-in.
15260 @item @code{virtual-terminal}
15261 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
15263 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
15264 A gexp denoting the name of the log-in program. The default log-in program is
15265 @command{login} from the Shadow tool suite.
15267 @item @code{login-arguments} (default: @code{'("-p")})
15268 A list of arguments to pass to @command{login}.
15270 @item @code{auto-login} (default: @code{#f})
15271 When passed a login name, as a string, the specified user will be logged
15272 in automatically without prompting for their login name or password.
15274 @item @code{hardware-acceleration?} (default: #f)
15275 Whether to use hardware acceleration.
15277 @item @code{font-engine} (default: @code{"pango"})
15278 Font engine used in Kmscon.
15280 @item @code{font-size} (default: @code{12})
15281 Font size used in Kmscon.
15283 @item @code{kmscon} (default: @var{kmscon})
15284 The Kmscon package to use.
15289 @cindex name service cache daemon
15291 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
15292 [#:name-services '()]
15293 Return a service that runs the libc name service cache daemon (nscd) with the
15294 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
15295 Service Switch}, for an example.
15297 For convenience, the Shepherd service for nscd provides the following actions:
15301 @cindex cache invalidation, nscd
15302 @cindex nscd, cache invalidation
15303 This invalidate the given cache. For instance, running:
15306 herd invalidate nscd hosts
15310 invalidates the host name lookup cache of nscd.
15313 Running @command{herd statistics nscd} displays information about nscd usage
15319 @defvr {Scheme Variable} %nscd-default-configuration
15320 This is the default @code{<nscd-configuration>} value (see below) used
15321 by @code{nscd-service}. It uses the caches defined by
15322 @code{%nscd-default-caches}; see below.
15325 @deftp {Data Type} nscd-configuration
15326 This is the data type representing the name service cache daemon (nscd)
15331 @item @code{name-services} (default: @code{'()})
15332 List of packages denoting @dfn{name services} that must be visible to
15333 the nscd---e.g., @code{(list @var{nss-mdns})}.
15335 @item @code{glibc} (default: @var{glibc})
15336 Package object denoting the GNU C Library providing the @command{nscd}
15339 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
15340 Name of the nscd log file. This is where debugging output goes when
15341 @code{debug-level} is strictly positive.
15343 @item @code{debug-level} (default: @code{0})
15344 Integer denoting the debugging levels. Higher numbers mean that more
15345 debugging output is logged.
15347 @item @code{caches} (default: @code{%nscd-default-caches})
15348 List of @code{<nscd-cache>} objects denoting things to be cached; see
15354 @deftp {Data Type} nscd-cache
15355 Data type representing a cache database of nscd and its parameters.
15359 @item @code{database}
15360 This is a symbol representing the name of the database to be cached.
15361 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
15362 @code{services}, which designate the corresponding NSS database
15363 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
15365 @item @code{positive-time-to-live}
15366 @itemx @code{negative-time-to-live} (default: @code{20})
15367 A number representing the number of seconds during which a positive or
15368 negative lookup result remains in cache.
15370 @item @code{check-files?} (default: @code{#t})
15371 Whether to check for updates of the files corresponding to
15374 For instance, when @var{database} is @code{hosts}, setting this flag
15375 instructs nscd to check for updates in @file{/etc/hosts} and to take
15378 @item @code{persistent?} (default: @code{#t})
15379 Whether the cache should be stored persistently on disk.
15381 @item @code{shared?} (default: @code{#t})
15382 Whether the cache should be shared among users.
15384 @item @code{max-database-size} (default: 32@tie{}MiB)
15385 Maximum size in bytes of the database cache.
15387 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
15388 @c settings, so leave them out.
15393 @defvr {Scheme Variable} %nscd-default-caches
15394 List of @code{<nscd-cache>} objects used by default by
15395 @code{nscd-configuration} (see above).
15397 It enables persistent and aggressive caching of service and host name
15398 lookups. The latter provides better host name lookup performance,
15399 resilience in the face of unreliable name servers, and also better
15400 privacy---often the result of host name lookups is in local cache, so
15401 external name servers do not even need to be queried.
15404 @anchor{syslog-configuration-type}
15407 @deftp {Data Type} syslog-configuration
15408 This data type represents the configuration of the syslog daemon.
15411 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
15412 The syslog daemon to use.
15414 @item @code{config-file} (default: @code{%default-syslog.conf})
15415 The syslog configuration file to use.
15420 @anchor{syslog-service}
15422 @deffn {Scheme Procedure} syslog-service @var{config}
15423 Return a service that runs a syslog daemon according to @var{config}.
15425 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
15426 information on the configuration file syntax.
15429 @defvr {Scheme Variable} guix-service-type
15430 This is the type of the service that runs the build daemon,
15431 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
15432 @code{guix-configuration} record as described below.
15435 @anchor{guix-configuration-type}
15436 @deftp {Data Type} guix-configuration
15437 This data type represents the configuration of the Guix build daemon.
15438 @xref{Invoking guix-daemon}, for more information.
15441 @item @code{guix} (default: @var{guix})
15442 The Guix package to use.
15444 @item @code{build-group} (default: @code{"guixbuild"})
15445 Name of the group for build user accounts.
15447 @item @code{build-accounts} (default: @code{10})
15448 Number of build user accounts to create.
15450 @item @code{authorize-key?} (default: @code{#t})
15451 @cindex substitutes, authorization thereof
15452 Whether to authorize the substitute keys listed in
15453 @code{authorized-keys}---by default that of
15454 @code{@value{SUBSTITUTE-SERVER-1}} and
15455 @code{@value{SUBSTITUTE-SERVER-2}}
15456 (@pxref{Substitutes}).
15458 When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
15459 changed by invoking @command{guix archive --authorize}. You must
15460 instead adjust @code{guix-configuration} as you wish and reconfigure the
15461 system. This ensures that your operating system configuration file is
15465 When booting or reconfiguring to a system where @code{authorize-key?}
15466 is true, the existing @file{/etc/guix/acl} file is backed up as
15467 @file{/etc/guix/acl.bak} if it was determined to be a manually modified
15468 file. This is to facilitate migration from earlier versions, which
15469 allowed for in-place modifications to @file{/etc/guix/acl}.
15472 @vindex %default-authorized-guix-keys
15473 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
15474 The list of authorized key files for archive imports, as a list of
15475 string-valued gexps (@pxref{Invoking guix archive}). By default, it
15476 contains that of @code{@value{SUBSTITUTE-SERVER-1}} and
15477 @code{@value{SUBSTITUTE-SERVER-2}} (@pxref{Substitutes}). See
15478 @code{substitute-urls} below for an example on how to change it.
15480 @item @code{use-substitutes?} (default: @code{#t})
15481 Whether to use substitutes.
15483 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
15484 The list of URLs where to look for substitutes by default.
15486 Suppose you would like to fetch substitutes from @code{guix.example.org}
15487 in addition to @code{@value{SUBSTITUTE-SERVER-1}}. You will need to do
15488 two things: (1) add @code{guix.example.org} to @code{substitute-urls},
15489 and (2) authorize its signing key, having done appropriate checks
15490 (@pxref{Substitute Server Authorization}). The configuration below does
15494 (guix-configuration
15496 (append (list "https://guix.example.org")
15497 %default-substitute-urls))
15499 (append (list (local-file "./guix.example.org-key.pub"))
15500 %default-authorized-guix-keys)))
15503 This example assumes that the file @file{./guix.example.org-key.pub}
15504 contains the public key that @code{guix.example.org} uses to sign
15507 @item @code{max-silent-time} (default: @code{0})
15508 @itemx @code{timeout} (default: @code{0})
15509 The number of seconds of silence and the number of seconds of activity,
15510 respectively, after which a build process times out. A value of zero
15511 disables the timeout.
15513 @item @code{log-compression} (default: @code{'bzip2})
15514 The type of compression used for build logs---one of @code{gzip},
15515 @code{bzip2}, or @code{none}.
15517 @item @code{discover?} (default: @code{#f})
15518 Whether to discover substitute servers on the local network using mDNS
15521 @item @code{extra-options} (default: @code{'()})
15522 List of extra command-line options for @command{guix-daemon}.
15524 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
15525 File where @command{guix-daemon}'s standard output and standard error
15528 @cindex HTTP proxy, for @code{guix-daemon}
15529 @cindex proxy, for @code{guix-daemon} HTTP access
15530 @item @code{http-proxy} (default: @code{#f})
15531 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
15532 derivations and substitutes.
15534 It is also possible to change the daemon's proxy at run time through the
15535 @code{set-http-proxy} action, which restarts it:
15538 herd set-http-proxy guix-daemon http://localhost:8118
15541 To clear the proxy settings, run:
15544 herd set-http-proxy guix-daemon
15547 @item @code{tmpdir} (default: @code{#f})
15548 A directory path where the @command{guix-daemon} will perform builds.
15553 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
15554 Run @var{udev}, which populates the @file{/dev} directory dynamically.
15555 udev rules can be provided as a list of files through the @var{rules}
15556 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
15557 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
15558 creation of such rule files.
15560 The @command{herd rules udev} command, as root, returns the name of the
15561 directory containing all the active udev rules.
15564 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
15565 Return a udev-rule file named @var{file-name} containing the rules
15566 defined by the @var{contents} literal.
15568 In the following example, a rule for a USB device is defined to be
15569 stored in the file @file{90-usb-thing.rules}. The rule runs a script
15570 upon detecting a USB device with a given product identifier.
15573 (define %example-udev-rule
15575 "90-usb-thing.rules"
15576 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
15577 "ATTR@{product@}==\"Example\", "
15578 "RUN+=\"/path/to/script\"")))
15582 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
15583 [#:groups @var{groups}]
15584 Return a service that extends @code{udev-service-type } with @var{rules}
15585 and @code{account-service-type} with @var{groups} as system groups.
15586 This works by creating a singleton service type
15587 @code{@var{name}-udev-rules}, of which the returned service is an
15590 Here we show how it can be used to extend @code{udev-service-type} with the
15591 previously defined rule @code{%example-udev-rule}.
15597 (cons (udev-rules-service 'usb-thing %example-udev-rule)
15598 %desktop-services)))
15602 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
15603 Return a udev file named @var{file-name} containing the rules defined
15604 within @var{file}, a file-like object.
15606 The following example showcases how we can use an existing rule file.
15609 (use-modules (guix download) ;for url-fetch
15610 (guix packages) ;for origin
15613 (define %android-udev-rules
15615 "51-android-udev.rules"
15616 (let ((version "20170910"))
15619 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
15620 "android-udev-rules/" version "/51-android.rules"))
15622 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
15626 Additionally, Guix package definitions can be included in @var{rules} in
15627 order to extend the udev rules with the definitions found under their
15628 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
15629 @var{file->udev-rule} example, we could have used the
15630 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
15631 packages android)} module.
15633 The following example shows how to use the @var{android-udev-rules}
15634 package so that the Android tool @command{adb} can detect devices
15635 without root privileges. It also details how to create the
15636 @code{adbusers} group, which is required for the proper functioning of
15637 the rules defined within the @code{android-udev-rules} package. To
15638 create such a group, we must define it both as part of the
15639 @code{supplementary-groups} of our @code{user-account} declaration, as
15640 well as in the @var{groups} of the @code{udev-rules-service} procedure.
15643 (use-modules (gnu packages android) ;for android-udev-rules
15644 (gnu system shadow) ;for user-group
15649 (users (cons (user-account
15651 (supplementary-groups
15652 '("adbusers" ;for adb
15653 "wheel" "netdev" "audio" "video")))))
15656 (cons (udev-rules-service 'android android-udev-rules
15657 #:groups '("adbusers"))
15658 %desktop-services)))
15661 @defvr {Scheme Variable} urandom-seed-service-type
15662 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
15663 when rebooting. It also tries to seed @file{/dev/urandom} from
15664 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
15668 @defvr {Scheme Variable} %random-seed-file
15669 This is the name of the file where some random bytes are saved by
15670 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
15671 It defaults to @file{/var/lib/random-seed}.
15676 @defvr {Scheme Variable} gpm-service-type
15677 This is the type of the service that runs GPM, the @dfn{general-purpose
15678 mouse daemon}, which provides mouse support to the Linux console. GPM
15679 allows users to use the mouse in the console, notably to select, copy,
15682 The value for services of this type must be a @code{gpm-configuration}
15683 (see below). This service is not part of @code{%base-services}.
15686 @deftp {Data Type} gpm-configuration
15687 Data type representing the configuration of GPM.
15690 @item @code{options} (default: @code{%default-gpm-options})
15691 Command-line options passed to @command{gpm}. The default set of
15692 options instruct @command{gpm} to listen to mouse events on
15693 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
15696 @item @code{gpm} (default: @code{gpm})
15697 The GPM package to use.
15702 @anchor{guix-publish-service-type}
15703 @deffn {Scheme Variable} guix-publish-service-type
15704 This is the service type for @command{guix publish} (@pxref{Invoking
15705 guix publish}). Its value must be a @code{guix-publish-configuration}
15706 object, as described below.
15708 This assumes that @file{/etc/guix} already contains a signing key pair as
15709 created by @command{guix archive --generate-key} (@pxref{Invoking guix
15710 archive}). If that is not the case, the service will fail to start.
15713 @deftp {Data Type} guix-publish-configuration
15714 Data type representing the configuration of the @code{guix publish}
15718 @item @code{guix} (default: @code{guix})
15719 The Guix package to use.
15721 @item @code{port} (default: @code{80})
15722 The TCP port to listen for connections.
15724 @item @code{host} (default: @code{"localhost"})
15725 The host (and thus, network interface) to listen to. Use
15726 @code{"0.0.0.0"} to listen on all the network interfaces.
15728 @item @code{advertise?} (default: @code{#f})
15729 When true, advertise the service on the local network @i{via} the DNS-SD
15730 protocol, using Avahi.
15732 This allows neighboring Guix devices with discovery on (see
15733 @code{guix-configuration} above) to discover this @command{guix publish}
15734 instance and to automatically download substitutes from it.
15736 @item @code{compression} (default: @code{'(("gzip" 3) ("zstd" 3))})
15737 This is a list of compression method/level tuple used when compressing
15738 substitutes. For example, to compress all substitutes with @emph{both} lzip
15739 at level 7 and gzip at level 9, write:
15742 '(("lzip" 7) ("gzip" 9))
15745 Level 9 achieves the best compression ratio at the expense of increased CPU
15746 usage, whereas level 1 achieves fast compression. @xref{Invoking guix
15747 publish}, for more information on the available compression methods and
15748 the tradeoffs involved.
15750 An empty list disables compression altogether.
15752 @item @code{nar-path} (default: @code{"nar"})
15753 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
15754 publish, @option{--nar-path}}, for details.
15756 @item @code{cache} (default: @code{#f})
15757 When it is @code{#f}, disable caching and instead generate archives on
15758 demand. Otherwise, this should be the name of a directory---e.g.,
15759 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
15760 archives and meta-data ready to be sent. @xref{Invoking guix publish,
15761 @option{--cache}}, for more information on the tradeoffs involved.
15763 @item @code{workers} (default: @code{#f})
15764 When it is an integer, this is the number of worker threads used for
15765 caching; when @code{#f}, the number of processors is used.
15766 @xref{Invoking guix publish, @option{--workers}}, for more information.
15768 @item @code{cache-bypass-threshold} (default: 10 MiB)
15769 When @code{cache} is true, this is the maximum size in bytes of a store
15770 item for which @command{guix publish} may bypass its cache in case of a
15771 cache miss. @xref{Invoking guix publish,
15772 @option{--cache-bypass-threshold}}, for more information.
15774 @item @code{ttl} (default: @code{#f})
15775 When it is an integer, this denotes the @dfn{time-to-live} in seconds
15776 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
15777 for more information.
15781 @anchor{rngd-service}
15782 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
15783 [#:device "/dev/hwrng"]
15784 Return a service that runs the @command{rngd} program from @var{rng-tools}
15785 to add @var{device} to the kernel's entropy pool. The service will fail if
15786 @var{device} does not exist.
15789 @anchor{pam-limits-service}
15790 @cindex session limits
15796 @cindex open file descriptors
15797 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
15799 Return a service that installs a configuration file for the
15800 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
15801 @code{pam_limits} module}. The procedure optionally takes a list of
15802 @code{pam-limits-entry} values, which can be used to specify
15803 @code{ulimit} limits and @code{nice} priority limits to user sessions.
15805 The following limits definition sets two hard and soft limits for all
15806 login sessions of users in the @code{realtime} group:
15809 (pam-limits-service
15811 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
15812 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
15815 The first entry increases the maximum realtime priority for
15816 non-privileged processes; the second entry lifts any restriction of the
15817 maximum address space that can be locked in memory. These settings are
15818 commonly used for real-time audio systems.
15820 Another useful example is raising the maximum number of open file
15821 descriptors that can be used:
15824 (pam-limits-service
15826 (pam-limits-entry "*" 'both 'nofile 100000)))
15829 In the above example, the asterisk means the limit should apply to any
15830 user. It is important to ensure the chosen value doesn't exceed the
15831 maximum system value visible in the @file{/proc/sys/fs/file-max} file,
15832 else the users would be prevented from login in. For more information
15833 about the Pluggable Authentication Module (PAM) limits, refer to the
15834 @samp{pam_limits} man page from the @code{linux-pam} package.
15837 @node Scheduled Job Execution
15838 @subsection Scheduled Job Execution
15842 @cindex scheduling jobs
15843 The @code{(gnu services mcron)} module provides an interface to
15844 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
15845 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
15846 Unix @command{cron} daemon; the main difference is that it is
15847 implemented in Guile Scheme, which provides a lot of flexibility when
15848 specifying the scheduling of jobs and their actions.
15850 The example below defines an operating system that runs the
15851 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
15852 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
15853 well as the @command{mkid} command on behalf of an unprivileged user
15854 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
15855 gexps to introduce job definitions that are passed to mcron
15856 (@pxref{G-Expressions}).
15859 (use-modules (guix) (gnu) (gnu services mcron))
15860 (use-package-modules base idutils)
15862 (define updatedb-job
15863 ;; Run 'updatedb' at 3AM every day. Here we write the
15864 ;; job's action as a Scheme procedure.
15865 #~(job '(next-hour '(3))
15867 (execl (string-append #$findutils "/bin/updatedb")
15869 "--prunepaths=/tmp /var/tmp /gnu/store"))))
15871 (define garbage-collector-job
15872 ;; Collect garbage 5 minutes after midnight every day.
15873 ;; The job's action is a shell command.
15874 #~(job "5 0 * * *" ;Vixie cron syntax
15877 (define idutils-job
15878 ;; Update the index database as user "charlie" at 12:15PM
15879 ;; and 19:15PM. This runs from the user's home directory.
15880 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
15881 (string-append #$idutils "/bin/mkid src")
15887 ;; %BASE-SERVICES already includes an instance of
15888 ;; 'mcron-service-type', which we extend with additional
15889 ;; jobs using 'simple-service'.
15890 (services (cons (simple-service 'my-cron-jobs
15892 (list garbage-collector-job
15898 For more complex jobs defined in Scheme where you need control over the top
15899 level, for instance to introduce a @code{use-modules} form, you can move your
15900 code to a separate program using the @code{program-file} procedure of the
15901 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
15905 (define %battery-alert-job
15906 ;; Beep when the battery percentage falls below %MIN-LEVEL.
15908 '(next-minute (range 0 60 1))
15910 "battery-alert.scm"
15911 (with-imported-modules (source-module-closure
15912 '((guix build utils)))
15914 (use-modules (guix build utils)
15917 (ice-9 textual-ports)
15920 (define %min-level 20)
15922 (setenv "LC_ALL" "C") ;ensure English output
15923 (and-let* ((input-pipe (open-pipe*
15925 #$(file-append acpi "/bin/acpi")))
15926 (output (get-string-all input-pipe))
15927 (m (string-match "Discharging, ([0-9]+)%" output))
15928 (level (string->number (match:substring m 1)))
15929 ((< level %min-level)))
15930 (format #t "warning: Battery level is low (~a%)~%" level)
15931 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
15934 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
15935 for more information on mcron job specifications. Below is the
15936 reference of the mcron service.
15938 On a running system, you can use the @code{schedule} action of the service to
15939 visualize the mcron jobs that will be executed next:
15942 # herd schedule mcron
15946 The example above lists the next five tasks that will be executed, but you can
15947 also specify the number of tasks to display:
15950 # herd schedule mcron 10
15953 @defvr {Scheme Variable} mcron-service-type
15954 This is the type of the @code{mcron} service, whose value is an
15955 @code{mcron-configuration} object.
15957 This service type can be the target of a service extension that provides
15958 it additional job specifications (@pxref{Service Composition}). In
15959 other words, it is possible to define services that provide additional
15963 @deftp {Data Type} mcron-configuration
15964 Data type representing the configuration of mcron.
15967 @item @code{mcron} (default: @var{mcron})
15968 The mcron package to use.
15971 This is a list of gexps (@pxref{G-Expressions}), where each gexp
15972 corresponds to an mcron job specification (@pxref{Syntax, mcron job
15973 specifications,, mcron, GNU@tie{}mcron}).
15979 @subsection Log Rotation
15982 @cindex log rotation
15984 Log files such as those found in @file{/var/log} tend to grow endlessly,
15985 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
15986 their contents in separate files, possibly compressed. The @code{(gnu
15987 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
15988 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
15990 This service is part of @code{%base-services}, and thus enabled by
15991 default, with the default settings, for commonly encountered log files.
15992 The example below shows how to extend it with an additional
15993 @dfn{rotation}, should you need to do that (usually, services that
15994 produce log files already take care of that):
15997 (use-modules (guix) (gnu))
15998 (use-service-modules admin)
16000 (define my-log-files
16001 ;; Log files that I want to rotate.
16002 '("/var/log/something.log" "/var/log/another.log"))
16006 (services (cons (simple-service 'rotate-my-stuff
16007 rottlog-service-type
16008 (list (log-rotation
16010 (files my-log-files))))
16014 @defvr {Scheme Variable} rottlog-service-type
16015 This is the type of the Rottlog service, whose value is a
16016 @code{rottlog-configuration} object.
16018 Other services can extend this one with new @code{log-rotation} objects
16019 (see below), thereby augmenting the set of files to be rotated.
16021 This service type can define mcron jobs (@pxref{Scheduled Job
16022 Execution}) to run the rottlog service.
16025 @deftp {Data Type} rottlog-configuration
16026 Data type representing the configuration of rottlog.
16029 @item @code{rottlog} (default: @code{rottlog})
16030 The Rottlog package to use.
16032 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
16033 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
16034 rottlog, GNU Rot[t]log Manual}).
16036 @item @code{rotations} (default: @code{%default-rotations})
16037 A list of @code{log-rotation} objects as defined below.
16040 This is a list of gexps where each gexp corresponds to an mcron job
16041 specification (@pxref{Scheduled Job Execution}).
16045 @deftp {Data Type} log-rotation
16046 Data type representing the rotation of a group of log files.
16048 Taking an example from the Rottlog manual (@pxref{Period Related File
16049 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
16055 (files '("/var/log/apache/*"))
16056 (options '("storedir apache-archives"
16062 The list of fields is as follows:
16065 @item @code{frequency} (default: @code{'weekly})
16066 The log rotation frequency, a symbol.
16069 The list of files or file glob patterns to rotate.
16071 @item @code{options} (default: @code{'()})
16072 The list of rottlog options for this rotation (@pxref{Configuration
16073 parameters,,, rottlog, GNU Rot[t]lg Manual}).
16075 @item @code{post-rotate} (default: @code{#f})
16076 Either @code{#f} or a gexp to execute once the rotation has completed.
16080 @defvr {Scheme Variable} %default-rotations
16081 Specifies weekly rotation of @code{%rotated-files} and of
16082 @file{/var/log/guix-daemon.log}.
16085 @defvr {Scheme Variable} %rotated-files
16086 The list of syslog-controlled files to be rotated. By default it is:
16087 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
16088 "/var/log/maillog")}.
16091 @node Networking Services
16092 @subsection Networking Services
16094 The @code{(gnu services networking)} module provides services to configure
16095 the network interface.
16097 @cindex DHCP, networking service
16098 @defvr {Scheme Variable} dhcp-client-service-type
16099 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
16100 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
16101 is the DHCP client package to use, @code{isc-dhcp} by default.
16104 @deffn {Scheme Procedure} dhcpd-service-type
16105 This type defines a service that runs a DHCP daemon. To create a
16106 service of this type, you must supply a @code{<dhcpd-configuration>}.
16110 (service dhcpd-service-type
16111 (dhcpd-configuration
16112 (config-file (local-file "my-dhcpd.conf"))
16113 (interfaces '("enp0s25"))))
16117 @deftp {Data Type} dhcpd-configuration
16119 @item @code{package} (default: @code{isc-dhcp})
16120 The package that provides the DHCP daemon. This package is expected to
16121 provide the daemon at @file{sbin/dhcpd} relative to its output
16122 directory. The default package is the
16123 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
16124 @item @code{config-file} (default: @code{#f})
16125 The configuration file to use. This is required. It will be passed to
16126 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
16127 object (@pxref{G-Expressions, file-like objects}). See @code{man
16128 dhcpd.conf} for details on the configuration file syntax.
16129 @item @code{version} (default: @code{"4"})
16130 The DHCP version to use. The ISC DHCP server supports the values ``4'',
16131 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
16132 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
16134 @item @code{run-directory} (default: @code{"/run/dhcpd"})
16135 The run directory to use. At service activation time, this directory
16136 will be created if it does not exist.
16137 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
16138 The PID file to use. This corresponds to the @code{-pf} option of
16139 @code{dhcpd}. See @code{man dhcpd} for details.
16140 @item @code{interfaces} (default: @code{'()})
16141 The names of the network interfaces on which dhcpd should listen for
16142 broadcasts. If this list is not empty, then its elements (which must be
16143 strings) will be appended to the @code{dhcpd} invocation when starting
16144 the daemon. It may not be necessary to explicitly specify any
16145 interfaces here; see @code{man dhcpd} for details.
16149 @defvr {Scheme Variable} static-networking-service-type
16150 This is the type for statically-configured network interfaces.
16151 @c TODO Document <static-networking> data structures.
16154 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
16155 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
16156 [#:requirement @code{'(udev)}]
16157 Return a service that starts @var{interface} with address @var{ip}. If
16158 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
16159 it must be a string specifying the default network gateway. @var{requirement}
16160 can be used to declare a dependency on another service before configuring the
16163 This procedure can be called several times, one for each network
16164 interface of interest. Behind the scenes what it does is extend
16165 @code{static-networking-service-type} with additional network interfaces
16171 (static-networking-service "eno1" "192.168.1.82"
16172 #:gateway "192.168.1.2"
16173 #:name-servers '("192.168.1.2"))
16180 @cindex network management
16181 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
16182 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
16183 management daemon that aims to simplify wired and wireless networking.
16185 This service adds the @var{wicd} package to the global profile, providing
16186 several commands to interact with the daemon and configure networking:
16187 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
16188 and @command{wicd-curses} user interfaces.
16191 @cindex ModemManager
16193 @defvr {Scheme Variable} modem-manager-service-type
16194 This is the service type for the
16195 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
16196 service. The value for this service type is a
16197 @code{modem-manager-configuration} record.
16199 This service is part of @code{%desktop-services} (@pxref{Desktop
16203 @deftp {Data Type} modem-manager-configuration
16204 Data type representing the configuration of ModemManager.
16207 @item @code{modem-manager} (default: @code{modem-manager})
16208 The ModemManager package to use.
16213 @cindex USB_ModeSwitch
16214 @cindex Modeswitching
16216 @defvr {Scheme Variable} usb-modeswitch-service-type
16217 This is the service type for the
16218 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch}
16219 service. The value for this service type is
16220 a @code{usb-modeswitch-configuration} record.
16222 When plugged in, some USB modems (and other USB devices) initially present
16223 themselves as a read-only storage medium and not as a modem. They need to be
16224 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
16225 installs udev rules to automatically modeswitch these devices when they are
16228 This service is part of @code{%desktop-services} (@pxref{Desktop
16232 @deftp {Data Type} usb-modeswitch-configuration
16233 Data type representing the configuration of USB_ModeSwitch.
16236 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
16237 The USB_ModeSwitch package providing the binaries for modeswitching.
16239 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
16240 The package providing the device data and udev rules file used by
16243 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
16244 Which config file to use for the USB_ModeSwitch dispatcher. By default the
16245 config file shipped with USB_ModeSwitch is used which disables logging to
16246 @file{/var/log} among other default settings. If set to @code{#f}, no config
16252 @cindex NetworkManager
16254 @defvr {Scheme Variable} network-manager-service-type
16255 This is the service type for the
16256 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
16257 service. The value for this service type is a
16258 @code{network-manager-configuration} record.
16260 This service is part of @code{%desktop-services} (@pxref{Desktop
16264 @deftp {Data Type} network-manager-configuration
16265 Data type representing the configuration of NetworkManager.
16268 @item @code{network-manager} (default: @code{network-manager})
16269 The NetworkManager package to use.
16271 @item @code{dns} (default: @code{"default"})
16272 Processing mode for DNS, which affects how NetworkManager uses the
16273 @code{resolv.conf} configuration file.
16277 NetworkManager will update @code{resolv.conf} to reflect the nameservers
16278 provided by currently active connections.
16281 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
16282 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
16283 then update @code{resolv.conf} to point to the local nameserver.
16285 With this setting, you can share your network connection. For example when
16286 you want to share your network connection to another laptop @i{via} an
16287 Ethernet cable, you can open @command{nm-connection-editor} and configure the
16288 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
16289 and reestablish the connection (or reboot).
16291 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
16292 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
16293 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
16294 browser on your host system, or connect to the VM @i{via} SSH
16295 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
16296 host-to-guest connection, run this command once:
16299 nmcli connection add type tun \
16300 connection.interface-name tap0 \
16301 tun.mode tap tun.owner $(id -u) \
16302 ipv4.method shared \
16303 ipv4.addresses 172.28.112.1/24
16306 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
16307 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
16308 @command{qemu-system-...}.
16311 NetworkManager will not modify @code{resolv.conf}.
16314 @item @code{vpn-plugins} (default: @code{'()})
16315 This is the list of available plugins for virtual private networks
16316 (VPNs). An example of this is the @code{network-manager-openvpn}
16317 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
16323 @deffn {Scheme Variable} connman-service-type
16324 This is the service type to run @url{https://01.org/connman,Connman},
16325 a network connection manager.
16327 Its value must be an
16328 @code{connman-configuration} record as in this example:
16331 (service connman-service-type
16332 (connman-configuration
16333 (disable-vpn? #t)))
16336 See below for details about @code{connman-configuration}.
16339 @deftp {Data Type} connman-configuration
16340 Data Type representing the configuration of connman.
16343 @item @code{connman} (default: @var{connman})
16344 The connman package to use.
16346 @item @code{disable-vpn?} (default: @code{#f})
16347 When true, disable connman's vpn plugin.
16351 @cindex WPA Supplicant
16352 @defvr {Scheme Variable} wpa-supplicant-service-type
16353 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
16354 supplicant}, an authentication daemon required to authenticate against
16355 encrypted WiFi or ethernet networks.
16358 @deftp {Data Type} wpa-supplicant-configuration
16359 Data type representing the configuration of WPA Supplicant.
16361 It takes the following parameters:
16364 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
16365 The WPA Supplicant package to use.
16367 @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
16368 List of services that should be started before WPA Supplicant starts.
16370 @item @code{dbus?} (default: @code{#t})
16371 Whether to listen for requests on D-Bus.
16373 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
16374 Where to store the PID file.
16376 @item @code{interface} (default: @code{#f})
16377 If this is set, it must specify the name of a network interface that
16378 WPA supplicant will control.
16380 @item @code{config-file} (default: @code{#f})
16381 Optional configuration file to use.
16383 @item @code{extra-options} (default: @code{'()})
16384 List of additional command-line arguments to pass to the daemon.
16388 @cindex hostapd service, for Wi-Fi access points
16389 @cindex Wi-Fi access points, hostapd service
16390 @defvr {Scheme Variable} hostapd-service-type
16391 This is the service type to run the @uref{https://w1.fi/hostapd/,
16392 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
16393 authentication servers. Its associated value must be a
16394 @code{hostapd-configuration} as shown below:
16397 ;; Use wlan1 to run the access point for "My Network".
16398 (service hostapd-service-type
16399 (hostapd-configuration
16400 (interface "wlan1")
16401 (ssid "My Network")
16406 @deftp {Data Type} hostapd-configuration
16407 This data type represents the configuration of the hostapd service, with
16408 the following fields:
16411 @item @code{package} (default: @code{hostapd})
16412 The hostapd package to use.
16414 @item @code{interface} (default: @code{"wlan0"})
16415 The network interface to run the WiFi access point.
16418 The SSID (@dfn{service set identifier}), a string that identifies this
16421 @item @code{broadcast-ssid?} (default: @code{#t})
16422 Whether to broadcast this SSID.
16424 @item @code{channel} (default: @code{1})
16425 The WiFi channel to use.
16427 @item @code{driver} (default: @code{"nl80211"})
16428 The driver interface type. @code{"nl80211"} is used with all Linux
16429 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
16430 RADIUS server that does # not control any wireless/wired driver.
16432 @item @code{extra-settings} (default: @code{""})
16433 Extra settings to append as-is to the hostapd configuration file. See
16434 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
16435 configuration file reference.
16439 @defvr {Scheme Variable} simulated-wifi-service-type
16440 This is the type of a service to simulate WiFi networking, which can be
16441 useful in virtual machines for testing purposes. The service loads the
16443 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
16444 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
16445 network that can be seen on @code{wlan0}, by default.
16447 The service's value is a @code{hostapd-configuration} record.
16451 @defvr {Scheme Variable} iptables-service-type
16452 This is the service type to set up an iptables configuration. iptables is a
16453 packet filtering framework supported by the Linux kernel. This service
16454 supports configuring iptables for both IPv4 and IPv6. A simple example
16455 configuration rejecting all incoming connections except those to the ssh port
16459 (service iptables-service-type
16460 (iptables-configuration
16461 (ipv4-rules (plain-file "iptables.rules" "*filter
16465 -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
16466 -A INPUT -p tcp --dport 22 -j ACCEPT
16467 -A INPUT -j REJECT --reject-with icmp-port-unreachable
16470 (ipv6-rules (plain-file "ip6tables.rules" "*filter
16474 -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
16475 -A INPUT -p tcp --dport 22 -j ACCEPT
16476 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
16482 @deftp {Data Type} iptables-configuration
16483 The data type representing the configuration of iptables.
16486 @item @code{iptables} (default: @code{iptables})
16487 The iptables package that provides @code{iptables-restore} and
16488 @code{ip6tables-restore}.
16489 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
16490 The iptables rules to use. It will be passed to @code{iptables-restore}.
16491 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
16493 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
16494 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
16495 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
16501 @defvr {Scheme Variable} nftables-service-type
16502 This is the service type to set up a nftables configuration. nftables is a
16503 netfilter project that aims to replace the existing iptables, ip6tables,
16504 arptables and ebtables framework. It provides a new packet filtering
16505 framework, a new user-space utility @command{nft}, and a compatibility layer
16506 for iptables. This service comes with a default ruleset
16507 @code{%default-nftables-ruleset} that rejecting all incoming connections
16508 except those to the ssh port 22. To use it, simply write:
16511 (service nftables-service-type)
16515 @deftp {Data Type} nftables-configuration
16516 The data type representing the configuration of nftables.
16519 @item @code{package} (default: @code{nftables})
16520 The nftables package that provides @command{nft}.
16521 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
16522 The nftables ruleset to use. This may be any ``file-like'' object
16523 (@pxref{G-Expressions, file-like objects}).
16527 @cindex NTP (Network Time Protocol), service
16528 @cindex ntpd, service for the Network Time Protocol daemon
16529 @cindex real time clock
16530 @defvr {Scheme Variable} ntp-service-type
16531 This is the type of the service running the @uref{https://www.ntp.org,
16532 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
16533 system clock synchronized with that of the specified NTP servers.
16535 The value of this service is an @code{ntpd-configuration} object, as described
16539 @deftp {Data Type} ntp-configuration
16540 This is the data type for the NTP service configuration.
16543 @item @code{servers} (default: @code{%ntp-servers})
16544 This is the list of servers (@code{<ntp-server>} records) with which
16545 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
16548 @item @code{allow-large-adjustment?} (default: @code{#t})
16549 This determines whether @command{ntpd} is allowed to make an initial
16550 adjustment of more than 1,000 seconds.
16552 @item @code{ntp} (default: @code{ntp})
16553 The NTP package to use.
16557 @defvr {Scheme Variable} %ntp-servers
16558 List of host names used as the default NTP servers. These are servers of the
16559 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
16562 @deftp {Data Type} ntp-server
16563 The data type representing the configuration of a NTP server.
16566 @item @code{type} (default: @code{'server})
16567 The type of the NTP server, given as a symbol. One of @code{'pool},
16568 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
16570 @item @code{address}
16571 The address of the server, as a string.
16573 @item @code{options}
16574 NTPD options to use with that specific server, given as a list of option names
16575 and/or of option names and values tuples. The following example define a server
16576 to use with the options @option{iburst} and @option{prefer}, as well as
16577 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
16582 (address "some.ntp.server.org")
16583 (options `(iburst (version 3) (maxpoll 16) prefer))))
16589 @deffn {Scheme Procedure} openntpd-service-type
16590 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
16591 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
16592 clock synchronized with that of the given servers.
16596 openntpd-service-type
16597 (openntpd-configuration
16598 (listen-on '("127.0.0.1" "::1"))
16599 (sensor '("udcf0 correction 70000"))
16600 (constraint-from '("www.gnu.org"))
16601 (constraints-from '("https://www.google.com/"))))
16606 @defvr {Scheme Variable} %openntpd-servers
16607 This variable is a list of the server addresses defined in
16608 @code{%ntp-servers}.
16611 @deftp {Data Type} openntpd-configuration
16613 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
16614 The openntpd executable to use.
16615 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
16616 A list of local IP addresses or hostnames the ntpd daemon should listen on.
16617 @item @code{query-from} (default: @code{'()})
16618 A list of local IP address the ntpd daemon should use for outgoing queries.
16619 @item @code{sensor} (default: @code{'()})
16620 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
16621 will listen to each sensor that actually exists and ignore non-existent ones.
16622 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
16624 @item @code{server} (default: @code{'()})
16625 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
16626 @item @code{servers} (default: @code{%openntp-servers})
16627 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
16628 @item @code{constraint-from} (default: @code{'()})
16629 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
16630 This time information is not used for precision but acts as an authenticated
16631 constraint, thereby reducing the impact of unauthenticated NTP
16632 man-in-the-middle attacks.
16633 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
16635 @item @code{constraints-from} (default: @code{'()})
16636 As with constraint from, specify a list of URLs, IP addresses or hostnames of
16637 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
16638 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
16643 @deffn {Scheme variable} inetd-service-type
16644 This service runs the @command{inetd} (@pxref{inetd invocation,,,
16645 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
16646 connections on internet sockets, and lazily starts the specified server
16647 program when a connection is made on one of these sockets.
16649 The value of this service is an @code{inetd-configuration} object. The
16650 following example configures the @command{inetd} daemon to provide the
16651 built-in @command{echo} service, as well as an smtp service which
16652 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
16653 gateway @code{hostname}:
16658 (inetd-configuration
16662 (socket-type 'stream)
16669 (socket-type 'stream)
16673 (program (file-append openssh "/bin/ssh"))
16675 '("ssh" "-qT" "-i" "/path/to/ssh_key"
16676 "-W" "smtp-server:25" "user@@hostname")))))))
16679 See below for more details about @code{inetd-configuration}.
16682 @deftp {Data Type} inetd-configuration
16683 Data type representing the configuration of @command{inetd}.
16686 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
16687 The @command{inetd} executable to use.
16689 @item @code{entries} (default: @code{'()})
16690 A list of @command{inetd} service entries. Each entry should be created
16691 by the @code{inetd-entry} constructor.
16695 @deftp {Data Type} inetd-entry
16696 Data type representing an entry in the @command{inetd} configuration.
16697 Each entry corresponds to a socket where @command{inetd} will listen for
16701 @item @code{node} (default: @code{#f})
16702 Optional string, a comma-separated list of local addresses
16703 @command{inetd} should use when listening for this service.
16704 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
16705 description of all options.
16707 A string, the name must correspond to an entry in @code{/etc/services}.
16708 @item @code{socket-type}
16709 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
16711 @item @code{protocol}
16712 A string, must correspond to an entry in @code{/etc/protocols}.
16713 @item @code{wait?} (default: @code{#t})
16714 Whether @command{inetd} should wait for the server to exit before
16715 listening to new service requests.
16717 A string containing the user (and, optionally, group) name of the user
16718 as whom the server should run. The group name can be specified in a
16719 suffix, separated by a colon or period, i.e.@: @code{"user"},
16720 @code{"user:group"} or @code{"user.group"}.
16721 @item @code{program} (default: @code{"internal"})
16722 The server program which will serve the requests, or @code{"internal"}
16723 if @command{inetd} should use a built-in service.
16724 @item @code{arguments} (default: @code{'()})
16725 A list strings or file-like objects, which are the server program's
16726 arguments, starting with the zeroth argument, i.e.@: the name of the
16727 program itself. For @command{inetd}'s internal services, this entry
16728 must be @code{'()} or @code{'("internal")}.
16731 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
16732 detailed discussion of each configuration field.
16735 @cindex opendht, distributed hash table network service
16736 @cindex dhtproxy, for use with jami
16737 @defvr {Scheme Variable} opendht-service-type
16738 This is the type of the service running a @uref{https://opendht.net,
16739 OpenDHT} node, @command{dhtnode}. The daemon can be used to host your
16740 own proxy service to the distributed hash table (DHT), for example to
16741 connect to with Jami, among other applications.
16743 @quotation Important
16744 When using the OpenDHT proxy server, the IP addresses it ``sees'' from
16745 the clients should be addresses reachable from other peers. In practice
16746 this means that a publicly reachable address is best suited for a proxy
16747 server, outside of your private network. For example, hosting the proxy
16748 server on a IPv4 private local network and exposing it via port
16749 forwarding could work for external peers, but peers local to the proxy
16750 would have their private addresses shared with the external peers,
16751 leading to connectivity problems.
16754 The value of this service is a @code{opendht-configuration} object, as
16758 @deftp {Data Type} opendht-configuration
16759 This is the data type for the OpenDHT service configuration.
16761 @c The fields documentation has been auto-generated using the
16762 @c configuration->documentation procedure from
16763 @c (gnu services configuration).
16764 Available @code{opendht-configuration} fields are:
16766 @deftypevr {@code{opendht-configuration} parameter} package opendht
16767 The @code{opendht} package to use.
16771 @deftypevr {@code{opendht-configuration} parameter} boolean peer-discovery?
16772 Whether to enable the multicast local peer discovery mechanism.
16774 Defaults to @samp{#f}.
16778 @deftypevr {@code{opendht-configuration} parameter} boolean enable-logging?
16779 Whether to enable logging messages to syslog. It is disabled by default
16780 as it is rather verbose.
16782 Defaults to @samp{#f}.
16786 @deftypevr {@code{opendht-configuration} parameter} boolean debug?
16787 Whether to enable debug-level logging messages. This has no effect if
16788 logging is disabled.
16790 Defaults to @samp{#f}.
16794 @deftypevr {@code{opendht-configuration} parameter} maybe-string bootstrap-host
16795 The node host name that is used to make the first connection to the
16796 network. A specific port value can be provided by appending the
16797 @code{:PORT} suffix. By default, it uses the Jami bootstrap nodes, but
16798 any host can be specified here. It's also possible to disable
16799 bootsrapping by setting this to the @code{'disabled} symbol.
16801 Defaults to @samp{"bootstrap.jami.net:4222"}.
16805 @deftypevr {@code{opendht-configuration} parameter} maybe-number port
16806 The UDP port to bind to. When set to @code{'disabled}, an available
16807 port is automatically selected.
16809 Defaults to @samp{4222}.
16813 @deftypevr {@code{opendht-configuration} parameter} maybe-number proxy-server-port
16814 Spawn a proxy server listening on the specified port.
16816 Defaults to @samp{disabled}.
16820 @deftypevr {@code{opendht-configuration} parameter} maybe-number proxy-server-port-tls
16821 Spawn a proxy server listening to TLS connections on the specified port.
16823 Defaults to @samp{disabled}.
16829 @defvr {Scheme Variable} tor-service-type
16830 This is the type for a service that runs the @uref{https://torproject.org,
16831 Tor} anonymous networking daemon. The service is configured using a
16832 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
16833 @code{tor} unprivileged user, which is a member of the @code{tor} group.
16837 @deftp {Data Type} tor-configuration
16839 @item @code{tor} (default: @code{tor})
16840 The package that provides the Tor daemon. This package is expected to provide
16841 the daemon at @file{bin/tor} relative to its output directory. The default
16842 package is the @uref{https://www.torproject.org, Tor Project's}
16845 @item @code{config-file} (default: @code{(plain-file "empty" "")})
16846 The configuration file to use. It will be appended to a default configuration
16847 file, and the final configuration file will be passed to @code{tor} via its
16848 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
16849 file-like objects}). See @code{man tor} for details on the configuration file
16852 @item @code{hidden-services} (default: @code{'()})
16853 The list of @code{<hidden-service>} records to use. For any hidden service
16854 you include in this list, appropriate configuration to enable the hidden
16855 service will be automatically added to the default configuration file. You
16856 may conveniently create @code{<hidden-service>} records using the
16857 @code{tor-hidden-service} procedure described below.
16859 @item @code{socks-socket-type} (default: @code{'tcp})
16860 The default socket type that Tor should use for its SOCKS socket. This must
16861 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
16862 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
16863 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
16864 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
16867 If you want to customize the SOCKS socket in more detail, leave
16868 @code{socks-socket-type} at its default value of @code{'tcp} and use
16869 @code{config-file} to override the default by providing your own
16870 @code{SocksPort} option.
16872 @item @code{control-socket?} (default: @code{#f})
16873 Whether or not to provide a ``control socket'' by which Tor can be
16874 controlled to, for instance, dynamically instantiate tor onion services.
16875 If @code{#t}, Tor will listen for control commands on the UNIX domain socket
16876 @file{/var/run/tor/control-sock}, which will be made writable by members of the
16882 @cindex hidden service
16883 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
16884 Define a new Tor @dfn{hidden service} called @var{name} and implementing
16885 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
16888 '((22 "127.0.0.1:22")
16889 (80 "127.0.0.1:8080"))
16892 In this example, port 22 of the hidden service is mapped to local port 22, and
16893 port 80 is mapped to local port 8080.
16895 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
16896 the @file{hostname} file contains the @code{.onion} host name for the hidden
16899 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
16900 project's documentation} for more information.
16903 The @code{(gnu services rsync)} module provides the following services:
16905 You might want an rsync daemon if you have files that you want available
16906 so anyone (or just yourself) can download existing files or upload new
16909 @deffn {Scheme Variable} rsync-service-type
16910 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
16911 The value for this service type is a
16912 @command{rsync-configuration} record as in this example:
16915 (service rsync-service-type)
16918 See below for details about @code{rsync-configuration}.
16921 @deftp {Data Type} rsync-configuration
16922 Data type representing the configuration for @code{rsync-service}.
16925 @item @code{package} (default: @var{rsync})
16926 @code{rsync} package to use.
16928 @item @code{port-number} (default: @code{873})
16929 TCP port on which @command{rsync} listens for incoming connections. If port
16930 is less than @code{1024} @command{rsync} needs to be started as the
16931 @code{root} user and group.
16933 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
16934 Name of the file where @command{rsync} writes its PID.
16936 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
16937 Name of the file where @command{rsync} writes its lock file.
16939 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
16940 Name of the file where @command{rsync} writes its log file.
16942 @item @code{use-chroot?} (default: @var{#t})
16943 Whether to use chroot for @command{rsync} shared directory.
16945 @item @code{share-path} (default: @file{/srv/rsync})
16946 Location of the @command{rsync} shared directory.
16948 @item @code{share-comment} (default: @code{"Rsync share"})
16949 Comment of the @command{rsync} shared directory.
16951 @item @code{read-only?} (default: @var{#f})
16952 Read-write permissions to shared directory.
16954 @item @code{timeout} (default: @code{300})
16955 I/O timeout in seconds.
16957 @item @code{user} (default: @var{"root"})
16958 Owner of the @code{rsync} process.
16960 @item @code{group} (default: @var{"root"})
16961 Group of the @code{rsync} process.
16963 @item @code{uid} (default: @var{"rsyncd"})
16964 User name or user ID that file transfers to and from that module should take
16965 place as when the daemon was run as @code{root}.
16967 @item @code{gid} (default: @var{"rsyncd"})
16968 Group name or group ID that will be used when accessing the module.
16973 The @code{(gnu services syncthing)} module provides the following services:
16976 You might want a syncthing daemon if you have files between two or more
16977 computers and want to sync them in real time, safely protected from
16980 @deffn {Scheme Variable} syncthing-service-type
16981 This is the service type for the @uref{https://syncthing.net/,
16982 syncthing} daemon, The value for this service type is a
16983 @command{syncthing-configuration} record as in this example:
16986 (service syncthing-service-type
16987 (syncthing-configuration (user "alice")))
16990 See below for details about @code{syncthing-configuration}.
16992 @deftp {Data Type} syncthing-configuration
16993 Data type representing the configuration for @code{syncthing-service-type}.
16996 @item @code{syncthing} (default: @var{syncthing})
16997 @code{syncthing} package to use.
16999 @item @code{arguments} (default: @var{'()})
17000 List of command-line arguments passing to @code{syncthing} binary.
17002 @item @code{logflags} (default: @var{0})
17003 Sum of logging flags, see
17004 @uref{https://docs.syncthing.net/users/syncthing.html#cmdoption-logflags, Syncthing documentation logflags}.
17006 @item @code{user} (default: @var{#f})
17007 The user as which the Syncthing service is to be run.
17008 This assumes that the specified user exists.
17010 @item @code{group} (default: @var{"users"})
17011 The group as which the Syncthing service is to be run.
17012 This assumes that the specified group exists.
17014 @item @code{home} (default: @var{#f})
17015 Common configuration and data directory. The default configuration
17016 directory is @file{$HOME} of the specified Syncthing @code{user}.
17022 Furthermore, @code{(gnu services ssh)} provides the following services.
17026 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
17027 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
17028 [#:allow-empty-passwords? #f] [#:root-login? #f] @
17029 [#:syslog-output? #t] [#:x11-forwarding? #t] @
17030 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
17031 [#:public-key-authentication? #t] [#:initialize? #t]
17032 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
17033 @var{host-key} must designate a file containing the host key, and readable
17036 When @var{daemonic?} is true, @command{lshd} will detach from the
17037 controlling terminal and log its output to syslogd, unless one sets
17038 @var{syslog-output?} to false. Obviously, it also makes lsh-service
17039 depend on existence of syslogd service. When @var{pid-file?} is true,
17040 @command{lshd} writes its PID to the file called @var{pid-file}.
17042 When @var{initialize?} is true, automatically create the seed and host key
17043 upon service activation if they do not exist yet. This may take long and
17044 require interaction.
17046 When @var{initialize?} is false, it is up to the user to initialize the
17047 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
17048 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
17049 basics,,, lsh, LSH Manual}).
17051 When @var{interfaces} is empty, lshd listens for connections on all the
17052 network interfaces; otherwise, @var{interfaces} must be a list of host names
17055 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
17056 passwords, and @var{root-login?} specifies whether to accept log-ins as
17059 The other options should be self-descriptive.
17064 @deffn {Scheme Variable} openssh-service-type
17065 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
17066 shell daemon, @command{sshd}. Its value must be an
17067 @code{openssh-configuration} record as in this example:
17070 (service openssh-service-type
17071 (openssh-configuration
17072 (x11-forwarding? #t)
17073 (permit-root-login 'without-password)
17075 `(("alice" ,(local-file "alice.pub"))
17076 ("bob" ,(local-file "bob.pub"))))))
17079 See below for details about @code{openssh-configuration}.
17081 This service can be extended with extra authorized keys, as in this
17085 (service-extension openssh-service-type
17086 (const `(("charlie"
17087 ,(local-file "charlie.pub")))))
17091 @deftp {Data Type} openssh-configuration
17092 This is the configuration record for OpenSSH's @command{sshd}.
17095 @item @code{openssh} (default @var{openssh})
17096 The Openssh package to use.
17098 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
17099 Name of the file where @command{sshd} writes its PID.
17101 @item @code{port-number} (default: @code{22})
17102 TCP port on which @command{sshd} listens for incoming connections.
17104 @item @code{permit-root-login} (default: @code{#f})
17105 This field determines whether and when to allow logins as root. If
17106 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
17107 If it's the symbol @code{'without-password}, then root logins are
17108 permitted but not with password-based authentication.
17110 @item @code{allow-empty-passwords?} (default: @code{#f})
17111 When true, users with empty passwords may log in. When false, they may
17114 @item @code{password-authentication?} (default: @code{#t})
17115 When true, users may log in with their password. When false, they have
17116 other authentication methods.
17118 @item @code{public-key-authentication?} (default: @code{#t})
17119 When true, users may log in using public key authentication. When
17120 false, users have to use other authentication method.
17122 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
17123 This is used only by protocol version 2.
17125 @item @code{x11-forwarding?} (default: @code{#f})
17126 When true, forwarding of X11 graphical client connections is
17127 enabled---in other words, @command{ssh} options @option{-X} and
17128 @option{-Y} will work.
17130 @item @code{allow-agent-forwarding?} (default: @code{#t})
17131 Whether to allow agent forwarding.
17133 @item @code{allow-tcp-forwarding?} (default: @code{#t})
17134 Whether to allow TCP forwarding.
17136 @item @code{gateway-ports?} (default: @code{#f})
17137 Whether to allow gateway ports.
17139 @item @code{challenge-response-authentication?} (default: @code{#f})
17140 Specifies whether challenge response authentication is allowed (e.g.@: via
17143 @item @code{use-pam?} (default: @code{#t})
17144 Enables the Pluggable Authentication Module interface. If set to
17145 @code{#t}, this will enable PAM authentication using
17146 @code{challenge-response-authentication?} and
17147 @code{password-authentication?}, in addition to PAM account and session
17148 module processing for all authentication types.
17150 Because PAM challenge response authentication usually serves an
17151 equivalent role to password authentication, you should disable either
17152 @code{challenge-response-authentication?} or
17153 @code{password-authentication?}.
17155 @item @code{print-last-log?} (default: @code{#t})
17156 Specifies whether @command{sshd} should print the date and time of the
17157 last user login when a user logs in interactively.
17159 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
17160 Configures external subsystems (e.g.@: file transfer daemon).
17162 This is a list of two-element lists, each of which containing the
17163 subsystem name and a command (with optional arguments) to execute upon
17166 The command @command{internal-sftp} implements an in-process SFTP
17167 server. Alternatively, one can specify the @command{sftp-server} command:
17169 (service openssh-service-type
17170 (openssh-configuration
17172 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
17175 @item @code{accepted-environment} (default: @code{'()})
17176 List of strings describing which environment variables may be exported.
17178 Each string gets on its own line. See the @code{AcceptEnv} option in
17179 @code{man sshd_config}.
17181 This example allows ssh-clients to export the @env{COLORTERM} variable.
17182 It is set by terminal emulators, which support colors. You can use it in
17183 your shell's resource file to enable colors for the prompt and commands
17184 if this variable is set.
17187 (service openssh-service-type
17188 (openssh-configuration
17189 (accepted-environment '("COLORTERM"))))
17192 @item @code{authorized-keys} (default: @code{'()})
17193 @cindex authorized keys, SSH
17194 @cindex SSH authorized keys
17195 This is the list of authorized keys. Each element of the list is a user
17196 name followed by one or more file-like objects that represent SSH public
17200 (openssh-configuration
17202 `(("rekado" ,(local-file "rekado.pub"))
17203 ("chris" ,(local-file "chris.pub"))
17204 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
17208 registers the specified public keys for user accounts @code{rekado},
17209 @code{chris}, and @code{root}.
17211 Additional authorized keys can be specified @i{via}
17212 @code{service-extension}.
17214 Note that this does @emph{not} interfere with the use of
17215 @file{~/.ssh/authorized_keys}.
17217 @item @code{log-level} (default: @code{'info})
17218 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
17219 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
17220 page for @file{sshd_config} for the full list of level names.
17222 @item @code{extra-content} (default: @code{""})
17223 This field can be used to append arbitrary text to the configuration file. It
17224 is especially useful for elaborate configurations that cannot be expressed
17225 otherwise. This configuration, for example, would generally disable root
17226 logins, but permit them from one specific IP address:
17229 (openssh-configuration
17231 Match Address 192.168.0.1
17232 PermitRootLogin yes"))
17238 @deffn {Scheme Procedure} dropbear-service [@var{config}]
17239 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
17240 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
17243 For example, to specify a Dropbear service listening on port 1234, add
17244 this call to the operating system's @code{services} field:
17247 (dropbear-service (dropbear-configuration
17248 (port-number 1234)))
17252 @deftp {Data Type} dropbear-configuration
17253 This data type represents the configuration of a Dropbear SSH daemon.
17256 @item @code{dropbear} (default: @var{dropbear})
17257 The Dropbear package to use.
17259 @item @code{port-number} (default: 22)
17260 The TCP port where the daemon waits for incoming connections.
17262 @item @code{syslog-output?} (default: @code{#t})
17263 Whether to enable syslog output.
17265 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
17266 File name of the daemon's PID file.
17268 @item @code{root-login?} (default: @code{#f})
17269 Whether to allow @code{root} logins.
17271 @item @code{allow-empty-passwords?} (default: @code{#f})
17272 Whether to allow empty passwords.
17274 @item @code{password-authentication?} (default: @code{#t})
17275 Whether to enable password-based authentication.
17280 @deffn {Scheme Variable} autossh-service-type
17281 This is the type for the @uref{https://www.harding.motd.ca/autossh,
17282 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
17283 restarting it as necessary should it die or stop passing traffic.
17284 AutoSSH can be run manually from the command-line by passing arguments
17285 to the binary @command{autossh} from the package @code{autossh}, but it
17286 can also be run as a Guix service. This latter use case is documented
17289 AutoSSH can be used to forward local traffic to a remote machine using
17290 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
17293 For example, to specify a service running autossh as the user
17294 @code{pino} and forwarding all local connections to port @code{8081} to
17295 @code{remote:8081} using an SSH tunnel, add this call to the operating
17296 system's @code{services} field:
17299 (service autossh-service-type
17300 (autossh-configuration
17302 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
17306 @deftp {Data Type} autossh-configuration
17307 This data type represents the configuration of an AutoSSH service.
17311 @item @code{user} (default @code{"autossh"})
17312 The user as which the AutoSSH service is to be run.
17313 This assumes that the specified user exists.
17315 @item @code{poll} (default @code{600})
17316 Specifies the connection poll time in seconds.
17318 @item @code{first-poll} (default @code{#f})
17319 Specifies how many seconds AutoSSH waits before the first connection
17320 test. After this first test, polling is resumed at the pace defined in
17321 @code{poll}. When set to @code{#f}, the first poll is not treated
17322 specially and will also use the connection poll specified in
17325 @item @code{gate-time} (default @code{30})
17326 Specifies how many seconds an SSH connection must be active before it is
17327 considered successful.
17329 @item @code{log-level} (default @code{1})
17330 The log level, corresponding to the levels used by syslog---so @code{0}
17331 is the most silent while @code{7} is the chattiest.
17333 @item @code{max-start} (default @code{#f})
17334 The maximum number of times SSH may be (re)started before AutoSSH exits.
17335 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
17337 @item @code{message} (default @code{""})
17338 The message to append to the echo message sent when testing connections.
17340 @item @code{port} (default @code{"0"})
17341 The ports used for monitoring the connection. When set to @code{"0"},
17342 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
17343 a positive integer, ports @var{n} and @var{n}+1 are used for
17344 monitoring the connection, such that port @var{n} is the base
17345 monitoring port and @code{n+1} is the echo port. When set to
17346 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
17347 integers, the ports @var{n} and @var{m} are used for monitoring the
17348 connection, such that port @var{n} is the base monitoring port and
17349 @var{m} is the echo port.
17351 @item @code{ssh-options} (default @code{'()})
17352 The list of command-line arguments to pass to @command{ssh} when it is
17353 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
17354 may cause undefined behaviour.
17360 @deffn {Scheme Variable} webssh-service-type
17361 This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
17362 program that runs a web SSH client. WebSSH can be run manually from the
17363 command-line by passing arguments to the binary @command{wssh} from the
17364 package @code{webssh}, but it can also be run as a Guix service. This
17365 latter use case is documented here.
17367 For example, to specify a service running WebSSH on loopback interface
17368 on port @code{8888} with reject policy with a list of allowed to
17369 connection hosts, and NGINX as a reverse-proxy to this service listening
17370 for HTTPS connection, add this call to the operating system's
17371 @code{services} field:
17374 (service webssh-service-type
17375 (webssh-configuration (address "127.0.0.1")
17378 (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
17379 "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
17381 (service nginx-service-type
17382 (nginx-configuration
17385 (nginx-server-configuration
17386 (inherit %webssh-configuration-nginx)
17387 (server-name '("webssh.example.com"))
17388 (listen '("443 ssl"))
17389 (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
17390 (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
17392 (cons (nginx-location-configuration
17393 (uri "/.well-known")
17394 (body '("root /var/www;")))
17395 (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
17399 @deftp {Data Type} webssh-configuration
17400 Data type representing the configuration for @code{webssh-service}.
17403 @item @code{package} (default: @var{webssh})
17404 @code{webssh} package to use.
17406 @item @code{user-name} (default: @var{"webssh"})
17407 User name or user ID that file transfers to and from that module should take
17410 @item @code{group-name} (default: @var{"webssh"})
17411 Group name or group ID that will be used when accessing the module.
17413 @item @code{address} (default: @var{#f})
17414 IP address on which @command{webssh} listens for incoming connections.
17416 @item @code{port} (default: @var{8888})
17417 TCP port on which @command{webssh} listens for incoming connections.
17419 @item @code{policy} (default: @var{#f})
17420 Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
17422 @item @code{known-hosts} (default: @var{'()})
17423 List of hosts which allowed for SSH connection from @command{webssh}.
17425 @item @code{log-file} (default: @file{"/var/log/webssh.log"})
17426 Name of the file where @command{webssh} writes its log file.
17428 @item @code{log-level} (default: @var{#f})
17434 @defvr {Scheme Variable} %facebook-host-aliases
17435 This variable contains a string for use in @file{/etc/hosts}
17436 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
17437 line contains a entry that maps a known server name of the Facebook
17438 on-line service---e.g., @code{www.facebook.com}---to the local
17439 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
17441 This variable is typically used in the @code{hosts-file} field of an
17442 @code{operating-system} declaration (@pxref{operating-system Reference,
17443 @file{/etc/hosts}}):
17446 (use-modules (gnu) (guix))
17449 (host-name "mymachine")
17452 ;; Create a /etc/hosts file with aliases for "localhost"
17453 ;; and "mymachine", as well as for Facebook servers.
17454 (plain-file "hosts"
17455 (string-append (local-host-aliases host-name)
17456 %facebook-host-aliases))))
17459 This mechanism can prevent programs running locally, such as Web
17460 browsers, from accessing Facebook.
17463 The @code{(gnu services avahi)} provides the following definition.
17465 @defvr {Scheme Variable} avahi-service-type
17466 This is the service that runs @command{avahi-daemon}, a system-wide
17467 mDNS/DNS-SD responder that allows for service discovery and
17468 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
17469 Its value must be an @code{avahi-configuration} record---see below.
17471 This service extends the name service cache daemon (nscd) so that it can
17472 resolve @code{.local} host names using
17473 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
17474 Service Switch}, for information on host name resolution.
17476 Additionally, add the @var{avahi} package to the system profile so that
17477 commands such as @command{avahi-browse} are directly usable.
17480 @deftp {Data Type} avahi-configuration
17481 Data type representation the configuration for Avahi.
17485 @item @code{host-name} (default: @code{#f})
17486 If different from @code{#f}, use that as the host name to
17487 publish for this machine; otherwise, use the machine's actual host name.
17489 @item @code{publish?} (default: @code{#t})
17490 When true, allow host names and services to be published (broadcast) over the
17493 @item @code{publish-workstation?} (default: @code{#t})
17494 When true, @command{avahi-daemon} publishes the machine's host name and IP
17495 address via mDNS on the local network. To view the host names published on
17496 your local network, you can run:
17499 avahi-browse _workstation._tcp
17502 @item @code{wide-area?} (default: @code{#f})
17503 When true, DNS-SD over unicast DNS is enabled.
17505 @item @code{ipv4?} (default: @code{#t})
17506 @itemx @code{ipv6?} (default: @code{#t})
17507 These fields determine whether to use IPv4/IPv6 sockets.
17509 @item @code{domains-to-browse} (default: @code{'()})
17510 This is a list of domains to browse.
17514 @deffn {Scheme Variable} openvswitch-service-type
17515 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
17516 service, whose value should be an @code{openvswitch-configuration}
17520 @deftp {Data Type} openvswitch-configuration
17521 Data type representing the configuration of Open vSwitch, a multilayer
17522 virtual switch which is designed to enable massive network automation
17523 through programmatic extension.
17526 @item @code{package} (default: @var{openvswitch})
17527 Package object of the Open vSwitch.
17532 @defvr {Scheme Variable} pagekite-service-type
17533 This is the service type for the @uref{https://pagekite.net, PageKite} service,
17534 a tunneling solution for making localhost servers publicly visible, even from
17535 behind restrictive firewalls or NAT without forwarded ports. The value for
17536 this service type is a @code{pagekite-configuration} record.
17538 Here's an example exposing the local HTTP and SSH daemons:
17541 (service pagekite-service-type
17542 (pagekite-configuration
17543 (kites '("http:@@kitename:localhost:80:@@kitesecret"
17544 "raw/22:@@kitename:localhost:22:@@kitesecret"))
17545 (extra-file "/etc/pagekite.rc")))
17549 @deftp {Data Type} pagekite-configuration
17550 Data type representing the configuration of PageKite.
17553 @item @code{package} (default: @var{pagekite})
17554 Package object of PageKite.
17556 @item @code{kitename} (default: @code{#f})
17557 PageKite name for authenticating to the frontend server.
17559 @item @code{kitesecret} (default: @code{#f})
17560 Shared secret for authenticating to the frontend server. You should probably
17561 put this inside @code{extra-file} instead.
17563 @item @code{frontend} (default: @code{#f})
17564 Connect to the named PageKite frontend server instead of the
17565 @uref{https://pagekite.net,,pagekite.net} service.
17567 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
17568 List of service kites to use. Exposes HTTP on port 80 by default. The format
17569 is @code{proto:kitename:host:port:secret}.
17571 @item @code{extra-file} (default: @code{#f})
17572 Extra configuration file to read, which you are expected to create manually.
17573 Use this to add additional options and manage shared secrets out-of-band.
17578 @defvr {Scheme Variable} yggdrasil-service-type
17579 The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
17580 Yggdrasil network}, an early-stage implementation of a fully end-to-end
17581 encrypted IPv6 network.
17584 Yggdrasil provides name-independent routing with cryptographically generated
17585 addresses. Static addressing means you can keep the same address as long as
17586 you want, even if you move to a new location, or generate a new address (by
17587 generating new keys) whenever you want.
17588 @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
17591 Pass it a value of @code{yggdrasil-configuration} to connect it to public
17592 peers and/or local peers.
17594 Here is an example using public peers and a static address. The static
17595 signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
17596 (the default value for @code{config-file}).
17599 ;; part of the operating-system declaration
17600 (service yggdrasil-service-type
17601 (yggdrasil-configuration
17602 (autoconf? #f) ;; use only the public peers
17605 ;; https://github.com/yggdrasil-network/public-peers
17606 '((peers . #("tcp://1.2.3.4:1337"))))
17607 ;; /etc/yggdrasil-private.conf is the default value for config-file
17611 # sample content for /etc/yggdrasil-private.conf
17613 # Your public encryption key. Your peers may ask you for this to put
17614 # into their AllowedEncryptionPublicKeys configuration.
17615 EncryptionPublicKey: 378dc5...
17617 # Your private encryption key. DO NOT share this with anyone!
17618 EncryptionPrivateKey: 0777...
17620 # Your public signing key. You should not ordinarily need to share
17621 # this with anyone.
17622 SigningPublicKey: e1664...
17624 # Your private signing key. DO NOT share this with anyone!
17625 SigningPrivateKey: 0589d...
17630 @deftp {Data Type} yggdrasil-configuration
17631 Data type representing the configuration of Yggdrasil.
17634 @item @code{package} (default: @code{yggdrasil})
17635 Package object of Yggdrasil.
17637 @item @code{json-config} (default: @code{'()})
17638 Contents of @file{/etc/yggdrasil.conf}. Will be merged with
17639 @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
17640 the Guix store, which is readable to all users. @strong{Do not store your
17641 private keys in it}. See the output of @code{yggdrasil -genconf} for a
17642 quick overview of valid keys and their default values.
17644 @item @code{autoconf?} (default: @code{#f})
17645 Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
17646 and peer with IPv6 neighbors.
17648 @item @code{log-level} (default: @code{'info})
17649 How much detail to include in logs. Use @code{'debug} for more detail.
17651 @item @code{log-to} (default: @code{'stdout})
17652 Where to send logs. By default, the service logs standard output to
17653 @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
17654 sends output to the running syslog service.
17656 @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
17657 What HJSON file to load sensitive data from. This is where private keys
17658 should be stored, which are necessary to specify if you don't want a
17659 randomized address after each restart. Use @code{#f} to disable. Options
17660 defined in this file take precedence over @code{json-config}. Use the output
17661 of @code{yggdrasil -genconf} as a starting point. To configure a static
17662 address, delete everything except these options:
17665 @item @code{EncryptionPublicKey}
17666 @item @code{EncryptionPrivateKey}
17667 @item @code{SigningPublicKey}
17668 @item @code{SigningPrivateKey}
17674 @defvr {Scheme Variable} ipfs-service-type
17675 The service type for connecting to the @uref{https://ipfs.io,IPFS network},
17676 a global, versioned, peer-to-peer file system. Pass it a
17677 @code{ipfs-configuration} to change the ports used for the gateway and API.
17679 Here's an example configuration, using some non-standard ports:
17682 (service ipfs-service-type
17683 (ipfs-configuration
17684 (gateway "/ip4/127.0.0.1/tcp/8880")
17685 (api "/ip4/127.0.0.1/tcp/8881")))
17689 @deftp {Data Type} ipfs-configuration
17690 Data type representing the configuration of IPFS.
17693 @item @code{package} (default: @code{go-ipfs})
17694 Package object of IPFS.
17696 @item @code{gateway} (default: @code{"/ip4/127.0.0.1/tcp/8082"})
17697 Address of the gateway, in ‘multiaddress’ format.
17699 @item @code{api} (default: @code{"/ip4/127.0.0.1/tcp/5001"})
17700 Address of the API endpoint, in ‘multiaddress’ format.
17705 @deffn {Scheme Variable} keepalived-service-type
17706 This is the type for the @uref{https://www.keepalived.org/, Keepalived}
17707 routing software, @command{keepalived}. Its value must be an
17708 @code{keepalived-configuration} record as in this example for master
17712 (service keepalived-service-type
17713 (keepalived-configuration
17714 (config-file (local-file "keepalived-master.conf"))))
17717 where @file{keepalived-master.conf}:
17720 vrrp_instance my-group @{
17723 virtual_router_id 100
17725 unicast_peer @{ 10.0.0.2 @}
17726 virtual_ipaddress @{
17732 and for backup machine:
17735 (service keepalived-service-type
17736 (keepalived-configuration
17737 (config-file (local-file "keepalived-backup.conf"))))
17740 where @file{keepalived-backup.conf}:
17743 vrrp_instance my-group @{
17746 virtual_router_id 100
17748 unicast_peer @{ 10.0.0.3 @}
17749 virtual_ipaddress @{
17756 @node Unattended Upgrades
17757 @subsection Unattended Upgrades
17759 @cindex unattended upgrades
17760 @cindex upgrades, unattended
17761 Guix provides a service to perform @emph{unattended upgrades}:
17762 periodically, the system automatically reconfigures itself from the
17763 latest Guix. Guix System has several properties that make unattended
17768 upgrades are transactional (either the upgrade succeeds or it fails, but
17769 you cannot end up with an ``in-between'' system state);
17771 the upgrade log is kept---you can view it with @command{guix system
17772 list-generations}---and you can roll back to any previous generation,
17773 should the upgraded system fail to behave as intended;
17775 channel code is authenticated so you know you can only run genuine code
17776 (@pxref{Channels});
17778 @command{guix system reconfigure} prevents downgrades, which makes it
17779 immune to @dfn{downgrade attacks}.
17782 To set up unattended upgrades, add an instance of
17783 @code{unattended-upgrade-service-type} like the one below to the list of
17784 your operating system services:
17787 (service unattended-upgrade-service-type)
17790 The defaults above set up weekly upgrades: every Sunday at midnight.
17791 You do not need to provide the operating system configuration file: it
17792 uses @file{/run/current-system/configuration.scm}, which ensures it
17793 always uses your latest configuration---@pxref{provenance-service-type},
17794 for more information about this file.
17796 There are several things that can be configured, in particular the
17797 periodicity and services (daemons) to be restarted upon completion.
17798 When the upgrade is successful, the service takes care of deleting
17799 system generations older that some threshold, as per @command{guix
17800 system delete-generations}. See the reference below for details.
17802 To ensure that upgrades are actually happening, you can run
17803 @command{guix system describe}. To investigate upgrade failures, visit
17804 the unattended upgrade log file (see below).
17806 @defvr {Scheme Variable} unattended-upgrade-service-type
17807 This is the service type for unattended upgrades. It sets up an mcron
17808 job (@pxref{Scheduled Job Execution}) that runs @command{guix system
17809 reconfigure} from the latest version of the specified channels.
17811 Its value must be a @code{unattended-upgrade-configuration} record (see
17815 @deftp {Data Type} unattended-upgrade-configuration
17816 This data type represents the configuration of the unattended upgrade
17817 service. The following fields are available:
17820 @item @code{schedule} (default: @code{"30 01 * * 0"})
17821 This is the schedule of upgrades, expressed as a gexp containing an
17822 mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
17823 mcron, GNU@tie{}mcron}).
17825 @item @code{channels} (default: @code{#~%default-channels})
17826 This gexp specifies the channels to use for the upgrade
17827 (@pxref{Channels}). By default, the tip of the official @code{guix}
17830 @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
17831 This field specifies the operating system configuration file to use.
17832 The default is to reuse the config file of the current configuration.
17834 There are cases, though, where referring to
17835 @file{/run/current-system/configuration.scm} is not enough, for instance
17836 because that file refers to extra files (SSH public keys, extra
17837 configuration files, etc.) @i{via} @code{local-file} and similar
17838 constructs. For those cases, we recommend something along these lines:
17841 (unattended-upgrade-configuration
17842 (operating-system-file
17843 (file-append (local-file "." "config-dir" #:recursive? #t)
17847 The effect here is to import all of the current directory into the
17848 store, and to refer to @file{config.scm} within that directory.
17849 Therefore, uses of @code{local-file} within @file{config.scm} will work
17850 as expected. @xref{G-Expressions}, for information about
17851 @code{local-file} and @code{file-append}.
17853 @item @code{services-to-restart} (default: @code{'(mcron)})
17854 This field specifies the Shepherd services to restart when the upgrade
17857 Those services are restarted right away upon completion, as with
17858 @command{herd restart}, which ensures that the latest version is
17859 running---remember that by default @command{guix system reconfigure}
17860 only restarts services that are not currently running, which is
17861 conservative: it minimizes disruption but leaves outdated services
17864 Use @command{herd status} to find out candidates for restarting.
17865 @xref{Services}, for general information about services. Common
17866 services to restart would include @code{ntpd} and @code{ssh-daemon}.
17868 By default, the @code{mcron} service is restarted. This ensures that
17869 the latest version of the unattended upgrade job will be used next time.
17871 @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
17872 This is the expiration time in seconds for system generations. System
17873 generations older that this amount of time are deleted with
17874 @command{guix system delete-generations} when an upgrade completes.
17877 The unattended upgrade service does not run the garbage collector. You
17878 will probably want to set up your own mcron job to run @command{guix gc}
17882 @item @code{maximum-duration} (default: @code{3600})
17883 Maximum duration in seconds for the upgrade; past that time, the upgrade
17886 This is primarily useful to ensure the upgrade does not end up
17887 rebuilding or re-downloading ``the world''.
17889 @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
17890 File where unattended upgrades are logged.
17895 @subsection X Window
17898 @cindex X Window System
17899 @cindex login manager
17900 Support for the X Window graphical display system---specifically
17901 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
17902 there is no @code{xorg-service} procedure. Instead, the X server is
17903 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
17906 @cindex GNOME, login manager
17907 GDM of course allows users to log in into window managers and desktop
17908 environments other than GNOME; for those using GNOME, GDM is required for
17909 features such as automatic screen locking.
17911 @cindex window manager
17912 To use X11, you must install at least one @dfn{window manager}---for
17913 example the @code{windowmaker} or @code{openbox} packages---preferably
17914 by adding it to the @code{packages} field of your operating system
17915 definition (@pxref{operating-system Reference, system-wide packages}).
17917 @defvr {Scheme Variable} gdm-service-type
17918 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
17919 Desktop Manager} (GDM), a program that manages graphical display servers and
17920 handles graphical user logins. Its value must be a @code{gdm-configuration}
17923 @cindex session types (X11)
17924 @cindex X11 session types
17925 GDM looks for @dfn{session types} described by the @file{.desktop} files in
17926 @file{/run/current-system/profile/share/xsessions} and allows users to choose
17927 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
17928 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
17929 set of packages automatically makes them available at the log-in screen.
17931 In addition, @file{~/.xsession} files are honored. When available,
17932 @file{~/.xsession} must be an executable that starts a window manager
17933 and/or other X clients.
17936 @deftp {Data Type} gdm-configuration
17938 @item @code{auto-login?} (default: @code{#f})
17939 @itemx @code{default-user} (default: @code{#f})
17940 When @code{auto-login?} is false, GDM presents a log-in screen.
17942 When @code{auto-login?} is true, GDM logs in directly as
17943 @code{default-user}.
17945 @item @code{debug?} (default: @code{#f})
17946 When true, GDM writes debug messages to its log.
17948 @item @code{gnome-shell-assets} (default: ...)
17949 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
17951 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
17952 Configuration of the Xorg graphical server.
17954 @item @code{xsession} (default: @code{(xinitrc)})
17955 Script to run before starting a X session.
17957 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
17958 File name of the @code{dbus-daemon} executable.
17960 @item @code{gdm} (default: @code{gdm})
17961 The GDM package to use.
17965 @defvr {Scheme Variable} slim-service-type
17966 This is the type for the SLiM graphical login manager for X11.
17968 Like GDM, SLiM looks for session types described by @file{.desktop} files and
17969 allows users to choose a session from the log-in screen using @kbd{F1}. It
17970 also honors @file{~/.xsession} files.
17972 Unlike GDM, SLiM does not spawn the user session on a different VT after
17973 logging in, which means that you can only start one graphical session. If you
17974 want to be able to run multiple graphical sessions at the same time you have
17975 to add multiple SLiM services to your system services. The following example
17976 shows how to replace the default GDM service with two SLiM services on tty7
17980 (use-modules (gnu services)
17981 (gnu services desktop)
17982 (gnu services xorg)
17983 (srfi srfi-1)) ;for 'remove'
17987 (services (cons* (service slim-service-type (slim-configuration
17990 (service slim-service-type (slim-configuration
17993 (modify-services %desktop-services
17994 (delete gdm-service-type)))))
17999 @deftp {Data Type} slim-configuration
18000 Data type representing the configuration of @code{slim-service-type}.
18003 @item @code{allow-empty-passwords?} (default: @code{#t})
18004 Whether to allow logins with empty passwords.
18006 @item @code{auto-login?} (default: @code{#f})
18007 @itemx @code{default-user} (default: @code{""})
18008 When @code{auto-login?} is false, SLiM presents a log-in screen.
18010 When @code{auto-login?} is true, SLiM logs in directly as
18011 @code{default-user}.
18013 @item @code{theme} (default: @code{%default-slim-theme})
18014 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
18015 The graphical theme to use and its name.
18017 @item @code{auto-login-session} (default: @code{#f})
18018 If true, this must be the name of the executable to start as the default
18019 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
18021 If false, a session described by one of the available @file{.desktop}
18022 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
18026 You must install at least one window manager in the system profile or in
18027 your user profile. Failing to do that, if @code{auto-login-session} is
18028 false, you will be unable to log in.
18031 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
18032 Configuration of the Xorg graphical server.
18034 @item @code{display} (default @code{":0"})
18035 The display on which to start the Xorg graphical server.
18037 @item @code{vt} (default @code{"vt7"})
18038 The VT on which to start the Xorg graphical server.
18040 @item @code{xauth} (default: @code{xauth})
18041 The XAuth package to use.
18043 @item @code{shepherd} (default: @code{shepherd})
18044 The Shepherd package used when invoking @command{halt} and
18047 @item @code{sessreg} (default: @code{sessreg})
18048 The sessreg package used in order to register the session.
18050 @item @code{slim} (default: @code{slim})
18051 The SLiM package to use.
18055 @defvr {Scheme Variable} %default-theme
18056 @defvrx {Scheme Variable} %default-theme-name
18057 The default SLiM theme and its name.
18061 @deftp {Data Type} sddm-configuration
18062 This is the data type representing the SDDM service configuration.
18065 @item @code{display-server} (default: "x11")
18066 Select display server to use for the greeter. Valid values are
18067 @samp{"x11"} or @samp{"wayland"}.
18069 @item @code{numlock} (default: "on")
18070 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
18072 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
18073 Command to run when halting.
18075 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
18076 Command to run when rebooting.
18078 @item @code{theme} (default "maldives")
18079 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
18080 @samp{"maldives"} or @samp{"maya"}.
18082 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
18083 Directory to look for themes.
18085 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
18086 Directory to look for faces.
18088 @item @code{default-path} (default "/run/current-system/profile/bin")
18089 Default PATH to use.
18091 @item @code{minimum-uid} (default: 1000)
18092 Minimum UID displayed in SDDM and allowed for log-in.
18094 @item @code{maximum-uid} (default: 2000)
18095 Maximum UID to display in SDDM.
18097 @item @code{remember-last-user?} (default #t)
18098 Remember last user.
18100 @item @code{remember-last-session?} (default #t)
18101 Remember last session.
18103 @item @code{hide-users} (default "")
18104 Usernames to hide from SDDM greeter.
18106 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
18107 Users with shells listed will be hidden from the SDDM greeter.
18109 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
18110 Script to run before starting a wayland session.
18112 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
18113 Directory to look for desktop files starting wayland sessions.
18115 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
18116 Configuration of the Xorg graphical server.
18118 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
18121 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
18124 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
18125 Script to run after starting xorg-server.
18127 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
18128 Script to run before stopping xorg-server.
18130 @item @code{xsession-command} (default: @code{xinitrc})
18131 Script to run before starting a X session.
18133 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
18134 Directory to look for desktop files starting X sessions.
18136 @item @code{minimum-vt} (default: 7)
18139 @item @code{auto-login-user} (default "")
18140 User to use for auto-login.
18142 @item @code{auto-login-session} (default "")
18143 Desktop file to use for auto-login.
18145 @item @code{relogin?} (default #f)
18146 Relogin after logout.
18151 @cindex login manager
18153 @defvr {Scheme Variable} sddm-service-type
18154 This is the type of the service to run the
18155 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
18156 must be a @code{sddm-configuration} record (see below).
18158 Here's an example use:
18161 (service sddm-service-type
18162 (sddm-configuration
18163 (auto-login-user "alice")
18164 (auto-login-session "xfce.desktop")))
18168 @deftp {Data Type} sddm-configuration
18169 This data type represents the configuration of the SDDM login manager.
18170 The available fields are:
18173 @item @code{sddm} (default: @code{sddm})
18174 The SDDM package to use.
18176 @item @code{display-server} (default: @code{"x11"})
18177 This must be either @code{"x11"} or @code{"wayland"}.
18179 @c FIXME: Add more fields.
18181 @item @code{auto-login-user} (default: @code{""})
18182 If non-empty, this is the user account under which to log in
18185 @item @code{auto-login-session} (default: @code{""})
18186 If non-empty, this is the @file{.desktop} file name to use as the
18187 auto-login session.
18191 @cindex Xorg, configuration
18192 @deftp {Data Type} xorg-configuration
18193 This data type represents the configuration of the Xorg graphical display
18194 server. Note that there is no Xorg service; instead, the X server is started
18195 by a ``display manager'' such as GDM, SDDM, and SLiM@. Thus, the configuration
18196 of these display managers aggregates an @code{xorg-configuration} record.
18199 @item @code{modules} (default: @code{%default-xorg-modules})
18200 This is a list of @dfn{module packages} loaded by the Xorg
18201 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
18203 @item @code{fonts} (default: @code{%default-xorg-fonts})
18204 This is a list of font directories to add to the server's @dfn{font path}.
18206 @item @code{drivers} (default: @code{'()})
18207 This must be either the empty list, in which case Xorg chooses a graphics
18208 driver automatically, or a list of driver names that will be tried in this
18209 order---e.g., @code{("modesetting" "vesa")}.
18211 @item @code{resolutions} (default: @code{'()})
18212 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
18213 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
18216 @cindex keyboard layout, for Xorg
18217 @cindex keymap, for Xorg
18218 @item @code{keyboard-layout} (default: @code{#f})
18219 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
18220 English (``qwerty'') for a 105-key PC keyboard.
18222 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
18223 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
18224 information on how to specify the keyboard layout.
18226 @item @code{extra-config} (default: @code{'()})
18227 This is a list of strings or objects appended to the configuration file. It
18228 is used to pass extra text to be added verbatim to the configuration file.
18230 @item @code{server} (default: @code{xorg-server})
18231 This is the package providing the Xorg server.
18233 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
18234 This is the list of command-line arguments to pass to the X server. The
18235 default is @code{-nolisten tcp}.
18239 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
18240 [@var{login-manager-service-type}]
18241 Tell the log-in manager (of type @var{login-manager-service-type}) to use
18242 @var{config}, an @code{<xorg-configuration>} record.
18244 Since the Xorg configuration is embedded in the log-in manager's
18245 configuration---e.g., @code{gdm-configuration}---this procedure provides a
18246 shorthand to set the Xorg configuration.
18249 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
18250 Return a @code{startx} script in which the modules, fonts, etc. specified
18251 in @var{config}, are available. The result should be used in place of
18254 Usually the X server is started by a login manager.
18258 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
18259 Add @var{package}, a package for a screen locker or screen saver whose
18260 command is @var{program}, to the set of setuid programs and add a PAM entry
18261 for it. For example:
18264 (screen-locker-service xlockmore "xlock")
18267 makes the good ol' XlockMore usable.
18271 @node Printing Services
18272 @subsection Printing Services
18274 @cindex printer support with CUPS
18275 The @code{(gnu services cups)} module provides a Guix service definition
18276 for the CUPS printing service. To add printer support to a Guix
18277 system, add a @code{cups-service} to the operating system definition:
18279 @deffn {Scheme Variable} cups-service-type
18280 The service type for the CUPS print server. Its value should be a valid
18281 CUPS configuration (see below). To use the default settings, simply
18284 (service cups-service-type)
18288 The CUPS configuration controls the basic things about your CUPS
18289 installation: what interfaces it listens on, what to do if a print job
18290 fails, how much logging to do, and so on. To actually add a printer,
18291 you have to visit the @url{http://localhost:631} URL, or use a tool such
18292 as GNOME's printer configuration services. By default, configuring a
18293 CUPS service will generate a self-signed certificate if needed, for
18294 secure connections to the print server.
18296 Suppose you want to enable the Web interface of CUPS and also add
18297 support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
18298 package and for HP printers @i{via} the @code{hplip-minimal} package.
18299 You can do that directly, like this (you need to use the
18300 @code{(gnu packages cups)} module):
18303 (service cups-service-type
18304 (cups-configuration
18305 (web-interface? #t)
18307 (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
18310 Note: If you wish to use the Qt5 based GUI which comes with the hplip
18311 package then it is suggested that you install the @code{hplip} package,
18312 either in your OS configuration file or as your user.
18314 The available configuration parameters follow. Each parameter
18315 definition is preceded by its type; for example, @samp{string-list foo}
18316 indicates that the @code{foo} parameter should be specified as a list of
18317 strings. There is also a way to specify the configuration as a string,
18318 if you have an old @code{cupsd.conf} file that you want to port over
18319 from some other system; see the end for more details.
18321 @c The following documentation was initially generated by
18322 @c (generate-documentation) in (gnu services cups). Manually maintained
18323 @c documentation is better, so we shouldn't hesitate to edit below as
18324 @c needed. However if the change you want to make to this documentation
18325 @c can be done in an automated way, it's probably easier to change
18326 @c (generate-documentation) than to make it below and have to deal with
18327 @c the churn as CUPS updates.
18330 Available @code{cups-configuration} fields are:
18332 @deftypevr {@code{cups-configuration} parameter} package cups
18336 @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list brlaser cups-filters epson-inkjet-printer-escpr foomatic-filters hplip-minimal splix)})
18337 Drivers and other extensions to the CUPS package.
18340 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
18341 Configuration of where to write logs, what directories to use for print
18342 spools, and related privileged configuration parameters.
18344 Available @code{files-configuration} fields are:
18346 @deftypevr {@code{files-configuration} parameter} log-location access-log
18347 Defines the access log filename. Specifying a blank filename disables
18348 access log generation. The value @code{stderr} causes log entries to be
18349 sent to the standard error file when the scheduler is running in the
18350 foreground, or to the system log daemon when run in the background. The
18351 value @code{syslog} causes log entries to be sent to the system log
18352 daemon. The server name may be included in filenames using the string
18353 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
18355 Defaults to @samp{"/var/log/cups/access_log"}.
18358 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
18359 Where CUPS should cache data.
18361 Defaults to @samp{"/var/cache/cups"}.
18364 @deftypevr {@code{files-configuration} parameter} string config-file-perm
18365 Specifies the permissions for all configuration files that the scheduler
18368 Note that the permissions for the printers.conf file are currently
18369 masked to only allow access from the scheduler user (typically root).
18370 This is done because printer device URIs sometimes contain sensitive
18371 authentication information that should not be generally known on the
18372 system. There is no way to disable this security feature.
18374 Defaults to @samp{"0640"}.
18377 @deftypevr {@code{files-configuration} parameter} log-location error-log
18378 Defines the error log filename. Specifying a blank filename disables
18379 error log generation. The value @code{stderr} causes log entries to be
18380 sent to the standard error file when the scheduler is running in the
18381 foreground, or to the system log daemon when run in the background. The
18382 value @code{syslog} causes log entries to be sent to the system log
18383 daemon. The server name may be included in filenames using the string
18384 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
18386 Defaults to @samp{"/var/log/cups/error_log"}.
18389 @deftypevr {@code{files-configuration} parameter} string fatal-errors
18390 Specifies which errors are fatal, causing the scheduler to exit. The
18395 No errors are fatal.
18398 All of the errors below are fatal.
18401 Browsing initialization errors are fatal, for example failed connections
18402 to the DNS-SD daemon.
18405 Configuration file syntax errors are fatal.
18408 Listen or Port errors are fatal, except for IPv6 failures on the
18409 loopback or @code{any} addresses.
18412 Log file creation or write errors are fatal.
18415 Bad startup file permissions are fatal, for example shared TLS
18416 certificate and key files with world-read permissions.
18419 Defaults to @samp{"all -browse"}.
18422 @deftypevr {@code{files-configuration} parameter} boolean file-device?
18423 Specifies whether the file pseudo-device can be used for new printer
18424 queues. The URI @uref{file:///dev/null} is always allowed.
18426 Defaults to @samp{#f}.
18429 @deftypevr {@code{files-configuration} parameter} string group
18430 Specifies the group name or ID that will be used when executing external
18433 Defaults to @samp{"lp"}.
18436 @deftypevr {@code{files-configuration} parameter} string log-file-perm
18437 Specifies the permissions for all log files that the scheduler writes.
18439 Defaults to @samp{"0644"}.
18442 @deftypevr {@code{files-configuration} parameter} log-location page-log
18443 Defines the page log filename. Specifying a blank filename disables
18444 page log generation. The value @code{stderr} causes log entries to be
18445 sent to the standard error file when the scheduler is running in the
18446 foreground, or to the system log daemon when run in the background. The
18447 value @code{syslog} causes log entries to be sent to the system log
18448 daemon. The server name may be included in filenames using the string
18449 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
18451 Defaults to @samp{"/var/log/cups/page_log"}.
18454 @deftypevr {@code{files-configuration} parameter} string remote-root
18455 Specifies the username that is associated with unauthenticated accesses
18456 by clients claiming to be the root user. The default is @code{remroot}.
18458 Defaults to @samp{"remroot"}.
18461 @deftypevr {@code{files-configuration} parameter} file-name request-root
18462 Specifies the directory that contains print jobs and other HTTP request
18465 Defaults to @samp{"/var/spool/cups"}.
18468 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
18469 Specifies the level of security sandboxing that is applied to print
18470 filters, backends, and other child processes of the scheduler; either
18471 @code{relaxed} or @code{strict}. This directive is currently only
18472 used/supported on macOS.
18474 Defaults to @samp{strict}.
18477 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
18478 Specifies the location of TLS certificates and private keys. CUPS will
18479 look for public and private keys in this directory: @file{.crt} files
18480 for PEM-encoded certificates and corresponding @file{.key} files for
18481 PEM-encoded private keys.
18483 Defaults to @samp{"/etc/cups/ssl"}.
18486 @deftypevr {@code{files-configuration} parameter} file-name server-root
18487 Specifies the directory containing the server configuration files.
18489 Defaults to @samp{"/etc/cups"}.
18492 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
18493 Specifies whether the scheduler calls fsync(2) after writing
18494 configuration or state files.
18496 Defaults to @samp{#f}.
18499 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
18500 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
18503 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
18504 Specifies the directory where temporary files are stored.
18506 Defaults to @samp{"/var/spool/cups/tmp"}.
18509 @deftypevr {@code{files-configuration} parameter} string user
18510 Specifies the user name or ID that is used when running external
18513 Defaults to @samp{"lp"}.
18516 @deftypevr {@code{files-configuration} parameter} string set-env
18517 Set the specified environment variable to be passed to child processes.
18519 Defaults to @samp{"variable value"}.
18523 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
18524 Specifies the logging level for the AccessLog file. The @code{config}
18525 level logs when printers and classes are added, deleted, or modified and
18526 when configuration files are accessed or updated. The @code{actions}
18527 level logs when print jobs are submitted, held, released, modified, or
18528 canceled, and any of the conditions for @code{config}. The @code{all}
18529 level logs all requests.
18531 Defaults to @samp{actions}.
18534 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
18535 Specifies whether to purge job history data automatically when it is no
18536 longer required for quotas.
18538 Defaults to @samp{#f}.
18541 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
18542 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
18543 For example, @samp{"_cups" "_print"} will tell network clients that both
18544 CUPS sharing and IPP Everywhere are supported.
18546 Defaults to @samp{"_cups"}.
18549 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
18550 Specifies which protocols to use for local printer sharing.
18552 Defaults to @samp{dnssd}.
18555 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
18556 Specifies whether the CUPS web interface is advertised.
18558 Defaults to @samp{#f}.
18561 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
18562 Specifies whether shared printers are advertised.
18564 Defaults to @samp{#f}.
18567 @deftypevr {@code{cups-configuration} parameter} string classification
18568 Specifies the security classification of the server. Any valid banner
18569 name can be used, including @samp{"classified"}, @samp{"confidential"},
18570 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
18571 banner can be omitted to disable secure printing functions.
18573 Defaults to @samp{""}.
18576 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
18577 Specifies whether users may override the classification (cover page) of
18578 individual print jobs using the @code{job-sheets} option.
18580 Defaults to @samp{#f}.
18583 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
18584 Specifies the default type of authentication to use.
18586 Defaults to @samp{Basic}.
18589 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
18590 Specifies whether encryption will be used for authenticated requests.
18592 Defaults to @samp{Required}.
18595 @deftypevr {@code{cups-configuration} parameter} string default-language
18596 Specifies the default language to use for text and web content.
18598 Defaults to @samp{"en"}.
18601 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
18602 Specifies the default paper size for new print queues. @samp{"Auto"}
18603 uses a locale-specific default, while @samp{"None"} specifies there is
18604 no default paper size. Specific size names are typically
18605 @samp{"Letter"} or @samp{"A4"}.
18607 Defaults to @samp{"Auto"}.
18610 @deftypevr {@code{cups-configuration} parameter} string default-policy
18611 Specifies the default access policy to use.
18613 Defaults to @samp{"default"}.
18616 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
18617 Specifies whether local printers are shared by default.
18619 Defaults to @samp{#t}.
18622 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
18623 Specifies the delay for updating of configuration and state files, in
18624 seconds. A value of 0 causes the update to happen as soon as possible,
18625 typically within a few milliseconds.
18627 Defaults to @samp{30}.
18630 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
18631 Specifies what to do when an error occurs. Possible values are
18632 @code{abort-job}, which will discard the failed print job;
18633 @code{retry-job}, which will retry the job at a later time;
18634 @code{retry-current-job}, which retries the failed job immediately; and
18635 @code{stop-printer}, which stops the printer.
18637 Defaults to @samp{stop-printer}.
18640 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
18641 Specifies the maximum cost of filters that are run concurrently, which
18642 can be used to minimize disk, memory, and CPU resource problems. A
18643 limit of 0 disables filter limiting. An average print to a
18644 non-PostScript printer needs a filter limit of about 200. A PostScript
18645 printer needs about half that (100). Setting the limit below these
18646 thresholds will effectively limit the scheduler to printing a single job
18649 Defaults to @samp{0}.
18652 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
18653 Specifies the scheduling priority of filters that are run to print a
18654 job. The nice value ranges from 0, the highest priority, to 19, the
18657 Defaults to @samp{0}.
18660 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
18661 Specifies whether to do reverse lookups on connecting clients. The
18662 @code{double} setting causes @code{cupsd} to verify that the hostname
18663 resolved from the address matches one of the addresses returned for that
18664 hostname. Double lookups also prevent clients with unregistered
18665 addresses from connecting to your server. Only set this option to
18666 @code{#t} or @code{double} if absolutely required.
18668 Defaults to @samp{#f}.
18671 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
18672 Specifies the number of seconds to wait before killing the filters and
18673 backend associated with a canceled or held job.
18675 Defaults to @samp{30}.
18678 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
18679 Specifies the interval between retries of jobs in seconds. This is
18680 typically used for fax queues but can also be used with normal print
18681 queues whose error policy is @code{retry-job} or
18682 @code{retry-current-job}.
18684 Defaults to @samp{30}.
18687 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
18688 Specifies the number of retries that are done for jobs. This is
18689 typically used for fax queues but can also be used with normal print
18690 queues whose error policy is @code{retry-job} or
18691 @code{retry-current-job}.
18693 Defaults to @samp{5}.
18696 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
18697 Specifies whether to support HTTP keep-alive connections.
18699 Defaults to @samp{#t}.
18702 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
18703 Specifies how long an idle client connection remains open, in seconds.
18705 Defaults to @samp{30}.
18708 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
18709 Specifies the maximum size of print files, IPP requests, and HTML form
18710 data. A limit of 0 disables the limit check.
18712 Defaults to @samp{0}.
18715 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
18716 Listens on the specified interfaces for connections. Valid values are
18717 of the form @var{address}:@var{port}, where @var{address} is either an
18718 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
18719 indicate all addresses. Values can also be file names of local UNIX
18720 domain sockets. The Listen directive is similar to the Port directive
18721 but allows you to restrict access to specific interfaces or networks.
18724 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
18725 Specifies the number of pending connections that will be allowed. This
18726 normally only affects very busy servers that have reached the MaxClients
18727 limit, but can also be triggered by large numbers of simultaneous
18728 connections. When the limit is reached, the operating system will
18729 refuse additional connections until the scheduler can accept the pending
18732 Defaults to @samp{128}.
18735 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
18736 Specifies a set of additional access controls.
18738 Available @code{location-access-controls} fields are:
18740 @deftypevr {@code{location-access-controls} parameter} file-name path
18741 Specifies the URI path to which the access control applies.
18744 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
18745 Access controls for all access to this path, in the same format as the
18746 @code{access-controls} of @code{operation-access-control}.
18748 Defaults to @samp{()}.
18751 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
18752 Access controls for method-specific access to this path.
18754 Defaults to @samp{()}.
18756 Available @code{method-access-controls} fields are:
18758 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
18759 If @code{#t}, apply access controls to all methods except the listed
18760 methods. Otherwise apply to only the listed methods.
18762 Defaults to @samp{#f}.
18765 @deftypevr {@code{method-access-controls} parameter} method-list methods
18766 Methods to which this access control applies.
18768 Defaults to @samp{()}.
18771 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
18772 Access control directives, as a list of strings. Each string should be
18773 one directive, such as @samp{"Order allow,deny"}.
18775 Defaults to @samp{()}.
18780 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
18781 Specifies the number of debugging messages that are retained for logging
18782 if an error occurs in a print job. Debug messages are logged regardless
18783 of the LogLevel setting.
18785 Defaults to @samp{100}.
18788 @deftypevr {@code{cups-configuration} parameter} log-level log-level
18789 Specifies the level of logging for the ErrorLog file. The value
18790 @code{none} stops all logging while @code{debug2} logs everything.
18792 Defaults to @samp{info}.
18795 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
18796 Specifies the format of the date and time in the log files. The value
18797 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
18799 Defaults to @samp{standard}.
18802 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
18803 Specifies the maximum number of simultaneous clients that are allowed by
18806 Defaults to @samp{100}.
18809 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
18810 Specifies the maximum number of simultaneous clients that are allowed
18811 from a single address.
18813 Defaults to @samp{100}.
18816 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
18817 Specifies the maximum number of copies that a user can print of each
18820 Defaults to @samp{9999}.
18823 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
18824 Specifies the maximum time a job may remain in the @code{indefinite}
18825 hold state before it is canceled. A value of 0 disables cancellation of
18828 Defaults to @samp{0}.
18831 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
18832 Specifies the maximum number of simultaneous jobs that are allowed. Set
18833 to 0 to allow an unlimited number of jobs.
18835 Defaults to @samp{500}.
18838 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
18839 Specifies the maximum number of simultaneous jobs that are allowed per
18840 printer. A value of 0 allows up to MaxJobs jobs per printer.
18842 Defaults to @samp{0}.
18845 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
18846 Specifies the maximum number of simultaneous jobs that are allowed per
18847 user. A value of 0 allows up to MaxJobs jobs per user.
18849 Defaults to @samp{0}.
18852 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
18853 Specifies the maximum time a job may take to print before it is
18854 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
18856 Defaults to @samp{10800}.
18859 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
18860 Specifies the maximum size of the log files before they are rotated, in
18861 bytes. The value 0 disables log rotation.
18863 Defaults to @samp{1048576}.
18866 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
18867 Specifies the maximum amount of time to allow between files in a
18868 multiple file print job, in seconds.
18870 Defaults to @samp{300}.
18873 @deftypevr {@code{cups-configuration} parameter} string page-log-format
18874 Specifies the format of PageLog lines. Sequences beginning with percent
18875 (@samp{%}) characters are replaced with the corresponding information,
18876 while all other characters are copied literally. The following percent
18877 sequences are recognized:
18881 insert a single percent character
18884 insert the value of the specified IPP attribute
18887 insert the number of copies for the current page
18890 insert the current page number
18893 insert the current date and time in common log format
18899 insert the printer name
18902 insert the username
18905 A value of the empty string disables page logging. The string @code{%p
18906 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
18907 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
18910 Defaults to @samp{""}.
18913 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
18914 Passes the specified environment variable(s) to child processes; a list
18917 Defaults to @samp{()}.
18920 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
18921 Specifies named access control policies.
18923 Available @code{policy-configuration} fields are:
18925 @deftypevr {@code{policy-configuration} parameter} string name
18926 Name of the policy.
18929 @deftypevr {@code{policy-configuration} parameter} string job-private-access
18930 Specifies an access list for a job's private values. @code{@@ACL} maps
18931 to the printer's requesting-user-name-allowed or
18932 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
18933 owner. @code{@@SYSTEM} maps to the groups listed for the
18934 @code{system-group} field of the @code{files-config} configuration,
18935 which is reified into the @code{cups-files.conf(5)} file. Other
18936 possible elements of the access list include specific user names, and
18937 @code{@@@var{group}} to indicate members of a specific group. The
18938 access list may also be simply @code{all} or @code{default}.
18940 Defaults to @samp{"@@OWNER @@SYSTEM"}.
18943 @deftypevr {@code{policy-configuration} parameter} string job-private-values
18944 Specifies the list of job values to make private, or @code{all},
18945 @code{default}, or @code{none}.
18947 Defaults to @samp{"job-name job-originating-host-name
18948 job-originating-user-name phone"}.
18951 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
18952 Specifies an access list for a subscription's private values.
18953 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
18954 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
18955 owner. @code{@@SYSTEM} maps to the groups listed for the
18956 @code{system-group} field of the @code{files-config} configuration,
18957 which is reified into the @code{cups-files.conf(5)} file. Other
18958 possible elements of the access list include specific user names, and
18959 @code{@@@var{group}} to indicate members of a specific group. The
18960 access list may also be simply @code{all} or @code{default}.
18962 Defaults to @samp{"@@OWNER @@SYSTEM"}.
18965 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
18966 Specifies the list of job values to make private, or @code{all},
18967 @code{default}, or @code{none}.
18969 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
18970 notify-subscriber-user-name notify-user-data"}.
18973 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
18974 Access control by IPP operation.
18976 Defaults to @samp{()}.
18980 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
18981 Specifies whether job files (documents) are preserved after a job is
18982 printed. If a numeric value is specified, job files are preserved for
18983 the indicated number of seconds after printing. Otherwise a boolean
18984 value applies indefinitely.
18986 Defaults to @samp{86400}.
18989 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
18990 Specifies whether the job history is preserved after a job is printed.
18991 If a numeric value is specified, the job history is preserved for the
18992 indicated number of seconds after printing. If @code{#t}, the job
18993 history is preserved until the MaxJobs limit is reached.
18995 Defaults to @samp{#t}.
18998 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
18999 Specifies the amount of time to wait for job completion before
19000 restarting the scheduler.
19002 Defaults to @samp{30}.
19005 @deftypevr {@code{cups-configuration} parameter} string rip-cache
19006 Specifies the maximum amount of memory to use when converting documents
19007 into bitmaps for a printer.
19009 Defaults to @samp{"128m"}.
19012 @deftypevr {@code{cups-configuration} parameter} string server-admin
19013 Specifies the email address of the server administrator.
19015 Defaults to @samp{"root@@localhost.localdomain"}.
19018 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
19019 The ServerAlias directive is used for HTTP Host header validation when
19020 clients connect to the scheduler from external interfaces. Using the
19021 special name @code{*} can expose your system to known browser-based DNS
19022 rebinding attacks, even when accessing sites through a firewall. If the
19023 auto-discovery of alternate names does not work, we recommend listing
19024 each alternate name with a ServerAlias directive instead of using
19027 Defaults to @samp{*}.
19030 @deftypevr {@code{cups-configuration} parameter} string server-name
19031 Specifies the fully-qualified host name of the server.
19033 Defaults to @samp{"localhost"}.
19036 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
19037 Specifies what information is included in the Server header of HTTP
19038 responses. @code{None} disables the Server header. @code{ProductOnly}
19039 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
19040 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
19041 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
19042 the output of the @code{uname} command. @code{Full} reports @code{CUPS
19043 2.0.0 (@var{uname}) IPP/2.0}.
19045 Defaults to @samp{Minimal}.
19048 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
19049 Listens on the specified interfaces for encrypted connections. Valid
19050 values are of the form @var{address}:@var{port}, where @var{address} is
19051 either an IPv6 address enclosed in brackets, an IPv4 address, or
19052 @code{*} to indicate all addresses.
19054 Defaults to @samp{()}.
19057 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
19058 Sets encryption options. By default, CUPS only supports encryption
19059 using TLS v1.0 or higher using known secure cipher suites. Security is
19060 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
19061 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
19062 suites, which are required for some older clients. The @code{AllowSSL3} option
19063 enables SSL v3.0, which is required for some older clients that do not support
19064 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
19065 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
19066 protocol version to TLS v1.1.
19068 Defaults to @samp{()}.
19071 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
19072 Specifies whether the scheduler requires clients to strictly adhere to
19073 the IPP specifications.
19075 Defaults to @samp{#f}.
19078 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
19079 Specifies the HTTP request timeout, in seconds.
19081 Defaults to @samp{300}.
19085 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
19086 Specifies whether the web interface is enabled.
19088 Defaults to @samp{#f}.
19091 At this point you're probably thinking ``oh dear, Guix manual, I like
19092 you but you can stop already with the configuration options''. Indeed.
19093 However, one more point: it could be that you have an existing
19094 @code{cupsd.conf} that you want to use. In that case, you can pass an
19095 @code{opaque-cups-configuration} as the configuration of a
19096 @code{cups-service-type}.
19098 Available @code{opaque-cups-configuration} fields are:
19100 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
19104 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
19105 The contents of the @code{cupsd.conf}, as a string.
19108 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
19109 The contents of the @code{cups-files.conf} file, as a string.
19112 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
19113 strings of the same name, you could instantiate a CUPS service like
19117 (service cups-service-type
19118 (opaque-cups-configuration
19119 (cupsd.conf cupsd.conf)
19120 (cups-files.conf cups-files.conf)))
19124 @node Desktop Services
19125 @subsection Desktop Services
19127 The @code{(gnu services desktop)} module provides services that are
19128 usually useful in the context of a ``desktop'' setup---that is, on a
19129 machine running a graphical display server, possibly with graphical user
19130 interfaces, etc. It also defines services that provide specific desktop
19131 environments like GNOME, Xfce or MATE.
19133 To simplify things, the module defines a variable containing the set of
19134 services that users typically expect on a machine with a graphical
19135 environment and networking:
19137 @defvr {Scheme Variable} %desktop-services
19138 This is a list of services that builds upon @code{%base-services} and
19139 adds or adjusts services for a typical ``desktop'' setup.
19141 In particular, it adds a graphical login manager (@pxref{X Window,
19142 @code{gdm-service-type}}), screen lockers, a network management tool
19143 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
19144 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
19145 energy and color management services, the @code{elogind} login and seat
19146 manager, the Polkit privilege service, the GeoClue location service, the
19147 AccountsService daemon that allows authorized users change system passwords,
19148 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
19149 name service switch service configured to be able to use @code{nss-mdns}
19150 (@pxref{Name Service Switch, mDNS}).
19153 The @code{%desktop-services} variable can be used as the @code{services}
19154 field of an @code{operating-system} declaration (@pxref{operating-system
19155 Reference, @code{services}}).
19157 Additionally, the @code{gnome-desktop-service-type},
19158 @code{xfce-desktop-service}, @code{mate-desktop-service-type},
19159 @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
19160 procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
19161 ``add GNOME'' means that system-level services like the backlight adjustment
19162 helpers and the power management utilities are added to the system, extending
19163 @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
19164 elevated privileges on a limited number of special-purpose system interfaces.
19165 Additionally, adding a service made by @code{gnome-desktop-service-type} adds
19166 the GNOME metapackage to the system profile. Likewise, adding the Xfce
19167 service not only adds the @code{xfce} metapackage to the system profile, but
19168 it also gives the Thunar file manager the ability to open a ``root-mode'' file
19169 management window, if the user authenticates using the administrator's
19170 password via the standard polkit graphical interface. To ``add MATE'' means
19171 that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
19172 to operate with elevated privileges on a limited number of special-purpose
19173 system interfaces. Additionally, adding a service of type
19174 @code{mate-desktop-service-type} adds the MATE metapackage to the system
19175 profile. ``Adding Enlightenment'' means that @code{dbus} is extended
19176 appropriately, and several of Enlightenment's binaries are set as setuid,
19177 allowing Enlightenment's screen locker and other functionality to work as
19180 The desktop environments in Guix use the Xorg display server by
19181 default. If you'd like to use the newer display server protocol
19182 called Wayland, you need to use the @code{sddm-service} instead of
19183 GDM as the graphical login manager. You should then
19184 select the ``GNOME (Wayland)'' session in SDDM@. Alternatively you can
19185 also try starting GNOME on Wayland manually from a TTY with the
19186 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
19187 gnome-session``. Currently only GNOME has support for Wayland.
19189 @defvr {Scheme Variable} gnome-desktop-service-type
19190 This is the type of the service that adds the @uref{https://www.gnome.org,
19191 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
19192 object (see below).
19194 This service adds the @code{gnome} package to the system profile, and extends
19195 polkit with the actions from @code{gnome-settings-daemon}.
19198 @deftp {Data Type} gnome-desktop-configuration
19199 Configuration record for the GNOME desktop environment.
19202 @item @code{gnome} (default: @code{gnome})
19203 The GNOME package to use.
19207 @defvr {Scheme Variable} xfce-desktop-service-type
19208 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
19209 desktop environment. Its value is an @code{xfce-desktop-configuration} object
19212 This service adds the @code{xfce} package to the system profile, and
19213 extends polkit with the ability for @code{thunar} to manipulate the file
19214 system as root from within a user session, after the user has authenticated
19215 with the administrator's password.
19217 Note that @code{xfce4-panel} and its plugin packages should be installed in
19218 the same profile to ensure compatibility. When using this service, you should
19219 add extra plugins (@code{xfce4-whiskermenu-plugin},
19220 @code{xfce4-weather-plugin}, etc.) to the @code{packages} field of your
19221 @code{operating-system}.
19224 @deftp {Data Type} xfce-desktop-configuration
19225 Configuration record for the Xfce desktop environment.
19228 @item @code{xfce} (default: @code{xfce})
19229 The Xfce package to use.
19233 @deffn {Scheme Variable} mate-desktop-service-type
19234 This is the type of the service that runs the @uref{https://mate-desktop.org/,
19235 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
19236 object (see below).
19238 This service adds the @code{mate} package to the system
19239 profile, and extends polkit with the actions from
19240 @code{mate-settings-daemon}.
19243 @deftp {Data Type} mate-desktop-configuration
19244 Configuration record for the MATE desktop environment.
19247 @item @code{mate} (default: @code{mate})
19248 The MATE package to use.
19252 @deffn {Scheme Variable} lxqt-desktop-service-type
19253 This is the type of the service that runs the @uref{https://lxqt-project.org,
19254 LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
19255 object (see below).
19257 This service adds the @code{lxqt} package to the system
19261 @deftp {Data Type} lxqt-desktop-configuration
19262 Configuration record for the LXQt desktop environment.
19265 @item @code{lxqt} (default: @code{lxqt})
19266 The LXQT package to use.
19270 @deffn {Scheme Variable} enlightenment-desktop-service-type
19271 Return a service that adds the @code{enlightenment} package to the system
19272 profile, and extends dbus with actions from @code{efl}.
19275 @deftp {Data Type} enlightenment-desktop-service-configuration
19277 @item @code{enlightenment} (default: @code{enlightenment})
19278 The enlightenment package to use.
19282 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
19283 the default @code{%desktop-services} variable doesn't include any of
19284 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
19285 @code{%desktop-services} in the @code{services} field of your
19286 @code{operating-system}:
19289 (use-modules (gnu))
19290 (use-service-modules desktop)
19293 ;; cons* adds items to the list given as its last argument.
19294 (services (cons* (service gnome-desktop-service-type)
19295 (service xfce-desktop-service)
19296 %desktop-services))
19300 These desktop environments will then be available as options in the
19301 graphical login window.
19303 The actual service definitions included in @code{%desktop-services} and
19304 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
19305 are described below.
19307 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
19308 Return a service that runs the ``system bus'', using @var{dbus}, with
19309 support for @var{services}.
19311 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
19312 facility. Its system bus is used to allow system services to communicate
19313 and to be notified of system-wide events.
19315 @var{services} must be a list of packages that provide an
19316 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
19317 and policy files. For example, to allow avahi-daemon to use the system bus,
19318 @var{services} must be equal to @code{(list avahi)}.
19321 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
19322 Return a service that runs the @code{elogind} login and
19323 seat management daemon. @uref{https://github.com/elogind/elogind,
19324 Elogind} exposes a D-Bus interface that can be used to know which users
19325 are logged in, know what kind of sessions they have open, suspend the
19326 system, inhibit system suspend, reboot the system, and other tasks.
19328 Elogind handles most system-level power events for a computer, for
19329 example suspending the system when a lid is closed, or shutting it down
19330 when the power button is pressed.
19332 The @var{config} keyword argument specifies the configuration for
19333 elogind, and should be the result of an @code{(elogind-configuration
19334 (@var{parameter} @var{value})...)} invocation. Available parameters and
19335 their default values are:
19338 @item kill-user-processes?
19340 @item kill-only-users
19342 @item kill-exclude-users
19344 @item inhibit-delay-max-seconds
19346 @item handle-power-key
19348 @item handle-suspend-key
19350 @item handle-hibernate-key
19352 @item handle-lid-switch
19354 @item handle-lid-switch-docked
19356 @item handle-lid-switch-external-power
19358 @item power-key-ignore-inhibited?
19360 @item suspend-key-ignore-inhibited?
19362 @item hibernate-key-ignore-inhibited?
19364 @item lid-switch-ignore-inhibited?
19366 @item holdoff-timeout-seconds
19370 @item idle-action-seconds
19372 @item runtime-directory-size-percent
19374 @item runtime-directory-size
19378 @item suspend-state
19379 @code{("mem" "standby" "freeze")}
19382 @item hibernate-state
19384 @item hibernate-mode
19385 @code{("platform" "shutdown")}
19386 @item hybrid-sleep-state
19388 @item hybrid-sleep-mode
19389 @code{("suspend" "platform" "shutdown")}
19393 @deffn {Scheme Procedure} accountsservice-service @
19394 [#:accountsservice @var{accountsservice}]
19395 Return a service that runs AccountsService, a system service that can
19396 list available accounts, change their passwords, and so on.
19397 AccountsService integrates with PolicyKit to enable unprivileged users
19398 to acquire the capability to modify their system configuration.
19399 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
19400 accountsservice web site} for more information.
19402 The @var{accountsservice} keyword argument is the @code{accountsservice}
19403 package to expose as a service.
19406 @deffn {Scheme Procedure} polkit-service @
19407 [#:polkit @var{polkit}]
19408 Return a service that runs the
19409 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
19410 management service}, which allows system administrators to grant access to
19411 privileged operations in a structured way. By querying the Polkit service, a
19412 privileged system component can know when it should grant additional
19413 capabilities to ordinary users. For example, an ordinary user can be granted
19414 the capability to suspend the system if the user is logged in locally.
19417 @defvr {Scheme Variable} polkit-wheel-service
19418 Service that adds the @code{wheel} group as admins to the Polkit
19419 service. This makes it so that users in the @code{wheel} group are queried
19420 for their own passwords when performing administrative actions instead of
19421 @code{root}'s, similar to the behaviour used by @code{sudo}.
19424 @defvr {Scheme Variable} upower-service-type
19425 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
19426 system-wide monitor for power consumption and battery levels, with the given
19427 configuration settings.
19429 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
19430 notably used by GNOME.
19433 @deftp {Data Type} upower-configuration
19434 Data type representation the configuration for UPower.
19438 @item @code{upower} (default: @var{upower})
19439 Package to use for @code{upower}.
19441 @item @code{watts-up-pro?} (default: @code{#f})
19442 Enable the Watts Up Pro device.
19444 @item @code{poll-batteries?} (default: @code{#t})
19445 Enable polling the kernel for battery level changes.
19447 @item @code{ignore-lid?} (default: @code{#f})
19448 Ignore the lid state, this can be useful if it's incorrect on a device.
19450 @item @code{use-percentage-for-policy?} (default: @code{#f})
19451 Whether battery percentage based policy should be used. The default is to use
19452 the time left, change to @code{#t} to use the percentage.
19454 @item @code{percentage-low} (default: @code{10})
19455 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
19456 at which the battery is considered low.
19458 @item @code{percentage-critical} (default: @code{3})
19459 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
19460 at which the battery is considered critical.
19462 @item @code{percentage-action} (default: @code{2})
19463 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
19464 at which action will be taken.
19466 @item @code{time-low} (default: @code{1200})
19467 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
19468 seconds at which the battery is considered low.
19470 @item @code{time-critical} (default: @code{300})
19471 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
19472 seconds at which the battery is considered critical.
19474 @item @code{time-action} (default: @code{120})
19475 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
19476 seconds at which action will be taken.
19478 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
19479 The action taken when @code{percentage-action} or @code{time-action} is
19480 reached (depending on the configuration of @code{use-percentage-for-policy?}).
19482 Possible values are:
19492 @code{'hybrid-sleep}.
19498 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
19499 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
19500 UDisks}, a @dfn{disk management} daemon that provides user interfaces
19501 with notifications and ways to mount/unmount disks. Programs that talk
19502 to UDisks include the @command{udisksctl} command, part of UDisks, and
19503 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
19504 it will only be able to use the file-system utilities installed in the
19505 system profile. For example if you want to be able to mount NTFS
19506 file-systems in read and write fashion, you'll need to have
19507 @code{ntfs-3g} installed system-wide.
19510 @deffn {Scheme Variable} colord-service-type
19511 This is the type of the service that runs @command{colord}, a system
19512 service with a D-Bus
19513 interface to manage the color profiles of input and output devices such as
19514 screens and scanners. It is notably used by the GNOME Color Manager graphical
19515 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
19516 site} for more information.
19519 @cindex scanner access
19520 @defvr {Scheme Variable} sane-service-type
19521 This service provides access to scanners @i{via}
19522 @uref{http://www.sane-project.org, SANE} by installing the necessary
19523 udev rules. It is included in @code{%desktop-services} (@pxref{Desktop
19524 Services}) and relies by default on @code{sane-backends-minimal} package
19525 (see below) for hardware support.
19528 @defvr {Scheme Variable} sane-backends-minimal
19529 The default package which the @code{sane-service-type} installs. It
19530 supports many recent scanners.
19533 @defvr {Scheme Variable} sane-backends
19534 This package includes support for all scanners that
19535 @code{sane-backends-minimal} supports, plus older Hewlett-Packard
19536 scanners supported by @code{hplip} package. In order to use this on
19537 a system which relies on @code{%desktop-services}, you may use
19538 @code{modify-services} (@pxref{Service Reference,
19539 @code{modify-services}}) as illustrated below:
19542 (use-modules (gnu))
19543 (use-service-modules
19546 (use-package-modules
19550 (define %my-desktop-services
19551 ;; List of desktop services that supports a broader range of scanners.
19552 (modify-services %desktop-services
19553 (sane-service-type _ => sane-backends)))
19557 (services %my-desktop-services)
19561 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
19562 Return a configuration allowing an application to access GeoClue
19563 location data. @var{name} is the Desktop ID of the application, without
19564 the @code{.desktop} part. If @var{allowed?} is true, the application
19565 will have access to location information by default. The boolean
19566 @var{system?} value indicates whether an application is a system component
19567 or not. Finally @var{users} is a list of UIDs of all users for which
19568 this application is allowed location info access. An empty users list
19569 means that all users are allowed.
19572 @defvr {Scheme Variable} %standard-geoclue-applications
19573 The standard list of well-known GeoClue application configurations,
19574 granting authority to the GNOME date-and-time utility to ask for the
19575 current location in order to set the time zone, and allowing the
19576 IceCat and Epiphany web browsers to request location information.
19577 IceCat and Epiphany both query the user before allowing a web page to
19578 know the user's location.
19581 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
19582 [#:whitelist '()] @
19583 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
19584 [#:submit-data? #f]
19585 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
19586 [#:submission-nick "geoclue"] @
19587 [#:applications %standard-geoclue-applications]
19588 Return a service that runs the GeoClue location service. This service
19589 provides a D-Bus interface to allow applications to request access to a
19590 user's physical location, and optionally to add information to online
19591 location databases. See
19592 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
19593 web site} for more information.
19596 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
19597 [@w{#:auto-enable? #f}]
19598 Return a service that runs the @command{bluetoothd} daemon, which
19599 manages all the Bluetooth devices and provides a number of D-Bus
19600 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
19601 powered automatically at boot, which can be useful when using a
19602 bluetooth keyboard or mouse.
19604 Users need to be in the @code{lp} group to access the D-Bus service.
19607 @defvr {Scheme Variable} gnome-keyring-service-type
19608 This is the type of the service that adds the
19609 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
19610 value is a @code{gnome-keyring-configuration} object (see below).
19612 This service adds the @code{gnome-keyring} package to the system profile
19613 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
19614 a user's login keyring when they log in or setting its password with passwd.
19617 @deftp {Data Type} gnome-keyring-configuration
19618 Configuration record for the GNOME Keyring service.
19621 @item @code{keyring} (default: @code{gnome-keyring})
19622 The GNOME keyring package to use.
19624 @item @code{pam-services}
19625 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
19626 services to extend, where @var{service} is the name of an existing
19627 service to extend and @var{kind} is one of @code{login} or
19630 If @code{login} is given, it adds an optional
19631 @code{pam_gnome_keyring.so} to the auth block without arguments and to
19632 the session block with @code{auto_start}. If @code{passwd} is given, it
19633 adds an optional @code{pam_gnome_keyring.so} to the password block
19636 By default, this field contains ``gdm-password'' with the value @code{login}
19637 and ``passwd'' is with the value @code{passwd}.
19642 @node Sound Services
19643 @subsection Sound Services
19645 @cindex sound support
19647 @cindex PulseAudio, sound support
19649 The @code{(gnu services sound)} module provides a service to configure the
19650 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
19651 preferred ALSA output driver.
19653 @deffn {Scheme Variable} alsa-service-type
19654 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
19655 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
19656 configuration file. The value for this type is a @command{alsa-configuration}
19657 record as in this example:
19660 (service alsa-service-type)
19663 See below for details about @code{alsa-configuration}.
19666 @deftp {Data Type} alsa-configuration
19667 Data type representing the configuration for @code{alsa-service}.
19670 @item @code{alsa-plugins} (default: @var{alsa-plugins})
19671 @code{alsa-plugins} package to use.
19673 @item @code{pulseaudio?} (default: @var{#t})
19674 Whether ALSA applications should transparently be made to use the
19675 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
19677 Using PulseAudio allows you to run several sound-producing applications
19678 at the same time and to individual control them @i{via}
19679 @command{pavucontrol}, among other things.
19681 @item @code{extra-options} (default: @var{""})
19682 String to append to the @file{/etc/asound.conf} file.
19687 Individual users who want to override the system configuration of ALSA can do
19688 it with the @file{~/.asoundrc} file:
19691 # In guix, we have to specify the absolute path for plugins.
19693 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
19696 # Routing ALSA to jack:
19697 # <http://jackaudio.org/faq/routing_alsa.html>.
19701 0 system:playback_1
19702 1 system:playback_2
19719 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
19722 @deffn {Scheme Variable} pulseaudio-service-type
19723 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
19724 sound server. It exists to allow system overrides of the default settings
19725 via @code{pulseaudio-configuration}, see below.
19728 This service overrides per-user configuration files. If you want
19729 PulseAudio to honor configuration files in @file{~/.config/pulse} you
19730 have to unset the environment variables @env{PULSE_CONFIG} and
19731 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
19735 This service on its own does not ensure, that the @code{pulseaudio} package
19736 exists on your machine. It merely adds configuration files for it, as
19737 detailed below. In the (admittedly unlikely) case, that you find yourself
19738 without a @code{pulseaudio} package, consider enabling it through the
19739 @code{alsa-service-type} above.
19743 @deftp {Data Type} pulseaudio-configuration
19744 Data type representing the configuration for @code{pulseaudio-service}.
19747 @item @code{client-conf} (default: @code{'()})
19748 List of settings to set in @file{client.conf}.
19749 Accepts a list of strings or a symbol-value pairs. A string will be
19750 inserted as-is with a newline added. A pair will be formatted as
19751 ``key = value'', again with a newline added.
19753 @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
19754 List of settings to set in @file{daemon.conf}, formatted just like
19757 @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
19758 Script file to use as @file{default.pa}.
19760 @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
19761 Script file to use as @file{system.pa}.
19765 @deffn {Scheme Variable} ladspa-service-type
19766 This service sets the @var{LADSPA_PATH} variable, so that programs, which
19767 respect it, e.g. PulseAudio, can load LADSPA plugins.
19769 The following example will setup the service to enable modules from the
19770 @code{swh-plugins} package:
19773 (service ladspa-service-type
19774 (ladspa-configuration (plugins (list swh-plugins))))
19777 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
19782 @node Database Services
19783 @subsection Database Services
19787 The @code{(gnu services databases)} module provides the following services.
19789 @subsubheading PostgreSQL
19791 The following example describes a PostgreSQL service with the default
19795 (service postgresql-service-type
19796 (postgresql-configuration
19797 (postgresql postgresql-10)))
19800 If the services fails to start, it may be due to an incompatible
19801 cluster already present in @var{data-directory}. Adjust it (or, if you
19802 don't need the cluster anymore, delete @var{data-directory}), then
19803 restart the service.
19805 Peer authentication is used by default and the @code{postgres} user
19806 account has no shell, which prevents the direct execution of @code{psql}
19807 commands as this user. To use @code{psql}, you can temporarily log in
19808 as @code{postgres} using a shell, create a PostgreSQL superuser with the
19809 same name as one of the system users and then create the associated
19813 sudo -u postgres -s /bin/sh
19814 createuser --interactive
19815 createdb $MY_USER_LOGIN # Replace appropriately.
19818 @deftp {Data Type} postgresql-configuration
19819 Data type representing the configuration for the
19820 @code{postgresql-service-type}.
19823 @item @code{postgresql}
19824 PostgreSQL package to use for the service.
19826 @item @code{port} (default: @code{5432})
19827 Port on which PostgreSQL should listen.
19829 @item @code{locale} (default: @code{"en_US.utf8"})
19830 Locale to use as the default when creating the database cluster.
19832 @item @code{config-file} (default: @code{(postgresql-config-file)})
19833 The configuration file to use when running PostgreSQL@. The default
19834 behaviour uses the postgresql-config-file record with the default values
19837 @item @code{log-directory} (default: @code{"/var/log/postgresql"})
19838 The directory where @command{pg_ctl} output will be written in a file
19839 named @code{"pg_ctl.log"}. This file can be useful to debug PostgreSQL
19840 configuration errors for instance.
19842 @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
19843 Directory in which to store the data.
19845 @item @code{extension-packages} (default: @code{'()})
19846 @cindex postgresql extension-packages
19847 Additional extensions are loaded from packages listed in
19848 @var{extension-packages}. Extensions are available at runtime. For instance,
19849 to create a geographic database using the @code{postgis} extension, a user can
19850 configure the postgresql-service as in this example:
19854 (use-package-modules databases geo)
19858 ;; postgresql is required to run `psql' but postgis is not required for
19859 ;; proper operation.
19860 (packages (cons* postgresql %base-packages))
19863 (service postgresql-service-type
19864 (postgresql-configuration
19865 (postgresql postgresql-10)
19866 (extension-packages (list postgis))))
19870 Then the extension becomes visible and you can initialise an empty geographic
19871 database in this way:
19875 > create database postgistest;
19876 > \connect postgistest;
19877 > create extension postgis;
19878 > create extension postgis_topology;
19881 There is no need to add this field for contrib extensions such as hstore or
19882 dblink as they are already loadable by postgresql. This field is only
19883 required to add extensions provided by other packages.
19888 @deftp {Data Type} postgresql-config-file
19889 Data type representing the PostgreSQL configuration file. As shown in
19890 the following example, this can be used to customize the configuration
19891 of PostgreSQL@. Note that you can use any G-expression or filename in
19892 place of this record, if you already have a configuration file you'd
19893 like to use for example.
19896 (service postgresql-service-type
19897 (postgresql-configuration
19899 (postgresql-config-file
19900 (log-destination "stderr")
19902 (plain-file "pg_hba.conf"
19904 local all all trust
19905 host all all 127.0.0.1/32 md5
19906 host all all ::1/128 md5"))
19908 '(("session_preload_libraries" "auto_explain")
19909 ("random_page_cost" 2)
19910 ("auto_explain.log_min_duration" "100 ms")
19911 ("work_mem" "500 MB")
19912 ("logging_collector" #t)
19913 ("log_directory" "/var/log/postgresql")))))))
19917 @item @code{log-destination} (default: @code{"syslog"})
19918 The logging method to use for PostgreSQL@. Multiple values are accepted,
19919 separated by commas.
19921 @item @code{hba-file} (default: @code{%default-postgres-hba})
19922 Filename or G-expression for the host-based authentication
19925 @item @code{ident-file} (default: @code{%default-postgres-ident})
19926 Filename or G-expression for the user name mapping configuration.
19928 @item @code{socket-directory} (default: @code{#false})
19929 Specifies the directory of the Unix-domain socket(s) on which PostgreSQL
19930 is to listen for connections from client applications. If set to
19931 @code{""} PostgreSQL does not listen on any Unix-domain sockets, in
19932 which case only TCP/IP sockets can be used to connect to the server.
19934 By default, the @code{#false} value means the PostgreSQL default value
19935 will be used, which is currently @samp{/tmp}.
19937 @item @code{extra-config} (default: @code{'()})
19938 List of additional keys and values to include in the PostgreSQL config
19939 file. Each entry in the list should be a list where the first element
19940 is the key, and the remaining elements are the values.
19942 The values can be numbers, booleans or strings and will be mapped to
19943 PostgreSQL parameters types @code{Boolean}, @code{String},
19944 @code{Numeric}, @code{Numeric with Unit} and @code{Enumerated} described
19945 @uref{https://www.postgresql.org/docs/current/config-setting.html,
19951 @deffn {Scheme Variable} postgresql-role-service-type
19952 This service allows to create PostgreSQL roles and databases after
19953 PostgreSQL service start. Here is an example of its use.
19956 (service postgresql-role-service-type
19957 (postgresql-role-configuration
19959 (list (postgresql-role
19961 (create-database? #t))))))
19964 This service can be extended with extra roles, as in this
19968 (service-extension postgresql-role-service-type
19969 (const (postgresql-role
19971 (create-database? #t))))
19975 @deftp {Data Type} postgresql-role
19976 PostgreSQL manages database access permissions using the concept of
19977 roles. A role can be thought of as either a database user, or a group
19978 of database users, depending on how the role is set up. Roles can own
19979 database objects (for example, tables) and can assign privileges on
19980 those objects to other roles to control who has access to which objects.
19986 @item @code{permissions} (default: @code{'(createdb login)})
19987 The role permissions list. Supported permissions are @code{bypassrls},
19988 @code{createdb}, @code{createrole}, @code{login}, @code{replication} and
19991 @item @code{create-database?} (default: @code{#f})
19992 Whether to create a database with the same name as the role.
19997 @deftp {Data Type} postgresql-role-configuration
19998 Data type representing the configuration of
19999 @var{postgresql-role-service-type}.
20002 @item @code{host} (default: @code{"/var/run/postgresql"})
20003 The PostgreSQL host to connect to.
20005 @item @code{log} (default: @code{"/var/log/postgresql_roles.log"})
20006 File name of the log file.
20008 @item @code{roles} (default: @code{'()})
20009 The initial PostgreSQL roles to create.
20013 @subsubheading MariaDB/MySQL
20015 @defvr {Scheme Variable} mysql-service-type
20016 This is the service type for a MySQL or MariaDB database server. Its value
20017 is a @code{mysql-configuration} object that specifies which package to use,
20018 as well as various settings for the @command{mysqld} daemon.
20021 @deftp {Data Type} mysql-configuration
20022 Data type representing the configuration of @var{mysql-service-type}.
20025 @item @code{mysql} (default: @var{mariadb})
20026 Package object of the MySQL database server, can be either @var{mariadb}
20029 For MySQL, a temporary root password will be displayed at activation time.
20030 For MariaDB, the root password is empty.
20032 @item @code{bind-address} (default: @code{"127.0.0.1"})
20033 The IP on which to listen for network connections. Use @code{"0.0.0.0"}
20034 to bind to all available network interfaces.
20036 @item @code{port} (default: @code{3306})
20037 TCP port on which the database server listens for incoming connections.
20039 @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
20040 Socket file to use for local (non-network) connections.
20042 @item @code{extra-content} (default: @code{""})
20043 Additional settings for the @file{my.cnf} configuration file.
20045 @item @code{extra-environment} (default: @code{#~'()})
20046 List of environment variables passed to the @command{mysqld} process.
20048 @item @code{auto-upgrade?} (default: @code{#t})
20049 Whether to automatically run @command{mysql_upgrade} after starting the
20050 service. This is necessary to upgrade the @dfn{system schema} after
20051 ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
20052 be disabled if you would rather do that manually.
20057 @subsubheading Memcached
20059 @defvr {Scheme Variable} memcached-service-type
20060 This is the service type for the @uref{https://memcached.org/,
20061 Memcached} service, which provides a distributed in memory cache. The
20062 value for the service type is a @code{memcached-configuration} object.
20066 (service memcached-service-type)
20069 @deftp {Data Type} memcached-configuration
20070 Data type representing the configuration of memcached.
20073 @item @code{memcached} (default: @code{memcached})
20074 The Memcached package to use.
20076 @item @code{interfaces} (default: @code{'("0.0.0.0")})
20077 Network interfaces on which to listen.
20079 @item @code{tcp-port} (default: @code{11211})
20080 Port on which to accept connections.
20082 @item @code{udp-port} (default: @code{11211})
20083 Port on which to accept UDP connections on, a value of 0 will disable
20084 listening on a UDP socket.
20086 @item @code{additional-options} (default: @code{'()})
20087 Additional command line options to pass to @code{memcached}.
20091 @subsubheading Redis
20093 @defvr {Scheme Variable} redis-service-type
20094 This is the service type for the @uref{https://redis.io/, Redis}
20095 key/value store, whose value is a @code{redis-configuration} object.
20098 @deftp {Data Type} redis-configuration
20099 Data type representing the configuration of redis.
20102 @item @code{redis} (default: @code{redis})
20103 The Redis package to use.
20105 @item @code{bind} (default: @code{"127.0.0.1"})
20106 Network interface on which to listen.
20108 @item @code{port} (default: @code{6379})
20109 Port on which to accept connections on, a value of 0 will disable
20110 listening on a TCP socket.
20112 @item @code{working-directory} (default: @code{"/var/lib/redis"})
20113 Directory in which to store the database and related files.
20117 @node Mail Services
20118 @subsection Mail Services
20122 The @code{(gnu services mail)} module provides Guix service definitions
20123 for email services: IMAP, POP3, and LMTP servers, as well as mail
20124 transport agents (MTAs). Lots of acronyms! These services are detailed
20125 in the subsections below.
20127 @subsubheading Dovecot Service
20129 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
20130 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
20133 By default, Dovecot does not need much configuration; the default
20134 configuration object created by @code{(dovecot-configuration)} will
20135 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
20136 certificate will be generated for TLS-protected connections, though
20137 Dovecot will also listen on cleartext ports by default. There are a
20138 number of options, though, which mail administrators might need to change,
20139 and as is the case with other services, Guix allows the system
20140 administrator to specify these parameters via a uniform Scheme interface.
20142 For example, to specify that mail is located at @code{maildir~/.mail},
20143 one would instantiate the Dovecot service like this:
20146 (dovecot-service #:config
20147 (dovecot-configuration
20148 (mail-location "maildir:~/.mail")))
20151 The available configuration parameters follow. Each parameter
20152 definition is preceded by its type; for example, @samp{string-list foo}
20153 indicates that the @code{foo} parameter should be specified as a list of
20154 strings. There is also a way to specify the configuration as a string,
20155 if you have an old @code{dovecot.conf} file that you want to port over
20156 from some other system; see the end for more details.
20158 @c The following documentation was initially generated by
20159 @c (generate-documentation) in (gnu services mail). Manually maintained
20160 @c documentation is better, so we shouldn't hesitate to edit below as
20161 @c needed. However if the change you want to make to this documentation
20162 @c can be done in an automated way, it's probably easier to change
20163 @c (generate-documentation) than to make it below and have to deal with
20164 @c the churn as dovecot updates.
20166 Available @code{dovecot-configuration} fields are:
20168 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
20169 The dovecot package.
20172 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
20173 A list of IPs or hosts where to listen for connections. @samp{*}
20174 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
20175 interfaces. If you want to specify non-default ports or anything more
20176 complex, customize the address and port fields of the
20177 @samp{inet-listener} of the specific services you are interested in.
20180 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
20181 List of protocols we want to serve. Available protocols include
20182 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
20184 Available @code{protocol-configuration} fields are:
20186 @deftypevr {@code{protocol-configuration} parameter} string name
20187 The name of the protocol.
20190 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
20191 UNIX socket path to the master authentication server to find users.
20192 This is used by imap (for shared users) and lda.
20193 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
20196 @deftypevr {@code{protocol-configuration} parameter} boolean imap-metadata?
20197 Whether to enable the @code{IMAP METADATA} extension as defined in
20198 @uref{https://tools.ietf.org/html/rfc5464,RFC@tie{}5464}, which provides
20199 a means for clients to set and retrieve per-mailbox, per-user metadata
20200 and annotations over IMAP.
20202 If this is @samp{#t}, you must also specify a dictionary @i{via} the
20203 @code{mail-attribute-dict} setting.
20205 Defaults to @samp{#f}.
20209 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-notify-capabilities
20210 Which NOTIFY capabilities to report to clients that first connect to
20211 the ManageSieve service, before authentication. These may differ from the
20212 capabilities offered to authenticated users. If this field is left empty,
20213 report what the Sieve interpreter supports by default.
20215 Defaults to @samp{()}.
20218 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-sieve-capability
20219 Which SIEVE capabilities to report to clients that first connect to
20220 the ManageSieve service, before authentication. These may differ from the
20221 capabilities offered to authenticated users. If this field is left empty,
20222 report what the Sieve interpreter supports by default.
20224 Defaults to @samp{()}.
20228 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
20229 Space separated list of plugins to load.
20232 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
20233 Maximum number of IMAP connections allowed for a user from each IP
20234 address. NOTE: The username is compared case-sensitively.
20235 Defaults to @samp{10}.
20240 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
20241 List of services to enable. Available services include @samp{imap},
20242 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
20245 Available @code{service-configuration} fields are:
20247 @deftypevr {@code{service-configuration} parameter} string kind
20248 The service kind. Valid values include @code{director},
20249 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
20250 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
20251 @code{tcpwrap}, @code{quota-warning}, or anything else.
20254 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
20255 Listeners for the service. A listener is either a
20256 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
20257 an @code{inet-listener-configuration}.
20258 Defaults to @samp{()}.
20260 Available @code{unix-listener-configuration} fields are:
20262 @deftypevr {@code{unix-listener-configuration} parameter} string path
20263 Path to the file, relative to @code{base-dir} field. This is also used as
20267 @deftypevr {@code{unix-listener-configuration} parameter} string mode
20268 The access mode for the socket.
20269 Defaults to @samp{"0600"}.
20272 @deftypevr {@code{unix-listener-configuration} parameter} string user
20273 The user to own the socket.
20274 Defaults to @samp{""}.
20277 @deftypevr {@code{unix-listener-configuration} parameter} string group
20278 The group to own the socket.
20279 Defaults to @samp{""}.
20283 Available @code{fifo-listener-configuration} fields are:
20285 @deftypevr {@code{fifo-listener-configuration} parameter} string path
20286 Path to the file, relative to @code{base-dir} field. This is also used as
20290 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
20291 The access mode for the socket.
20292 Defaults to @samp{"0600"}.
20295 @deftypevr {@code{fifo-listener-configuration} parameter} string user
20296 The user to own the socket.
20297 Defaults to @samp{""}.
20300 @deftypevr {@code{fifo-listener-configuration} parameter} string group
20301 The group to own the socket.
20302 Defaults to @samp{""}.
20306 Available @code{inet-listener-configuration} fields are:
20308 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
20309 The protocol to listen for.
20312 @deftypevr {@code{inet-listener-configuration} parameter} string address
20313 The address on which to listen, or empty for all addresses.
20314 Defaults to @samp{""}.
20317 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
20318 The port on which to listen.
20321 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
20322 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
20324 Defaults to @samp{#t}.
20329 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
20330 Maximum number of simultaneous client connections per process. Once
20331 this number of connections is received, the next incoming connection
20332 will prompt Dovecot to spawn another process. If set to 0,
20333 @code{default-client-limit} is used instead.
20335 Defaults to @samp{0}.
20339 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
20340 Number of connections to handle before starting a new process.
20341 Typically the only useful values are 0 (unlimited) or 1. 1 is more
20342 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
20343 Defaults to @samp{1}.
20347 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
20348 Maximum number of processes that can exist for this service. If set to
20349 0, @code{default-process-limit} is used instead.
20351 Defaults to @samp{0}.
20355 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
20356 Number of processes to always keep waiting for more connections.
20357 Defaults to @samp{0}.
20360 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
20361 If you set @samp{service-count 0}, you probably need to grow
20363 Defaults to @samp{256000000}.
20368 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
20369 Dict configuration, as created by the @code{dict-configuration}
20372 Available @code{dict-configuration} fields are:
20374 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
20375 A list of key-value pairs that this dict should hold.
20376 Defaults to @samp{()}.
20381 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
20382 A list of passdb configurations, each one created by the
20383 @code{passdb-configuration} constructor.
20385 Available @code{passdb-configuration} fields are:
20387 @deftypevr {@code{passdb-configuration} parameter} string driver
20388 The driver that the passdb should use. Valid values include
20389 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
20391 Defaults to @samp{"pam"}.
20394 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
20395 Space separated list of arguments to the passdb driver.
20396 Defaults to @samp{""}.
20401 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
20402 List of userdb configurations, each one created by the
20403 @code{userdb-configuration} constructor.
20405 Available @code{userdb-configuration} fields are:
20407 @deftypevr {@code{userdb-configuration} parameter} string driver
20408 The driver that the userdb should use. Valid values include
20409 @samp{passwd} and @samp{static}.
20410 Defaults to @samp{"passwd"}.
20413 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
20414 Space separated list of arguments to the userdb driver.
20415 Defaults to @samp{""}.
20418 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
20419 Override fields from passwd.
20420 Defaults to @samp{()}.
20425 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
20426 Plug-in configuration, created by the @code{plugin-configuration}
20430 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
20431 List of namespaces. Each item in the list is created by the
20432 @code{namespace-configuration} constructor.
20434 Available @code{namespace-configuration} fields are:
20436 @deftypevr {@code{namespace-configuration} parameter} string name
20437 Name for this namespace.
20440 @deftypevr {@code{namespace-configuration} parameter} string type
20441 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
20442 Defaults to @samp{"private"}.
20445 @deftypevr {@code{namespace-configuration} parameter} string separator
20446 Hierarchy separator to use. You should use the same separator for
20447 all namespaces or some clients get confused. @samp{/} is usually a good
20448 one. The default however depends on the underlying mail storage
20450 Defaults to @samp{""}.
20453 @deftypevr {@code{namespace-configuration} parameter} string prefix
20454 Prefix required to access this namespace. This needs to be
20455 different for all namespaces. For example @samp{Public/}.
20456 Defaults to @samp{""}.
20459 @deftypevr {@code{namespace-configuration} parameter} string location
20460 Physical location of the mailbox. This is in the same format as
20461 mail_location, which is also the default for it.
20462 Defaults to @samp{""}.
20465 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
20466 There can be only one INBOX, and this setting defines which
20468 Defaults to @samp{#f}.
20471 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
20472 If namespace is hidden, it's not advertised to clients via NAMESPACE
20473 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
20474 useful when converting from another server with different namespaces
20475 which you want to deprecate but still keep working. For example you can
20476 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
20478 Defaults to @samp{#f}.
20481 @deftypevr {@code{namespace-configuration} parameter} boolean list?
20482 Show the mailboxes under this namespace with the LIST command. This
20483 makes the namespace visible for clients that do not support the NAMESPACE
20484 extension. The special @code{children} value lists child mailboxes, but
20485 hides the namespace prefix.
20486 Defaults to @samp{#t}.
20489 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
20490 Namespace handles its own subscriptions. If set to @code{#f}, the
20491 parent namespace handles them. The empty prefix should always have this
20493 Defaults to @samp{#t}.
20496 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
20497 List of predefined mailboxes in this namespace.
20498 Defaults to @samp{()}.
20500 Available @code{mailbox-configuration} fields are:
20502 @deftypevr {@code{mailbox-configuration} parameter} string name
20503 Name for this mailbox.
20506 @deftypevr {@code{mailbox-configuration} parameter} string auto
20507 @samp{create} will automatically create this mailbox.
20508 @samp{subscribe} will both create and subscribe to the mailbox.
20509 Defaults to @samp{"no"}.
20512 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
20513 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
20514 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
20515 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
20516 Defaults to @samp{()}.
20523 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
20524 Base directory where to store runtime data.
20525 Defaults to @samp{"/var/run/dovecot/"}.
20528 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
20529 Greeting message for clients.
20530 Defaults to @samp{"Dovecot ready."}.
20533 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
20534 List of trusted network ranges. Connections from these IPs are
20535 allowed to override their IP addresses and ports (for logging and for
20536 authentication checks). @samp{disable-plaintext-auth} is also ignored
20537 for these networks. Typically you would specify your IMAP proxy servers
20539 Defaults to @samp{()}.
20542 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
20543 List of login access check sockets (e.g.@: tcpwrap).
20544 Defaults to @samp{()}.
20547 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
20548 Show more verbose process titles (in ps). Currently shows user name
20549 and IP address. Useful for seeing who is actually using the IMAP
20550 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
20552 Defaults to @samp{#f}.
20555 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
20556 Should all processes be killed when Dovecot master process shuts down.
20557 Setting this to @code{#f} means that Dovecot can be upgraded without
20558 forcing existing client connections to close (although that could also
20559 be a problem if the upgrade is e.g.@: due to a security fix).
20560 Defaults to @samp{#t}.
20563 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
20564 If non-zero, run mail commands via this many connections to doveadm
20565 server, instead of running them directly in the same process.
20566 Defaults to @samp{0}.
20569 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
20570 UNIX socket or host:port used for connecting to doveadm server.
20571 Defaults to @samp{"doveadm-server"}.
20574 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
20575 List of environment variables that are preserved on Dovecot startup
20576 and passed down to all of its child processes. You can also give
20577 key=value pairs to always set specific settings.
20580 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
20581 Disable LOGIN command and all other plaintext authentications unless
20582 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
20583 matches the local IP (i.e.@: you're connecting from the same computer),
20584 the connection is considered secure and plaintext authentication is
20585 allowed. See also ssl=required setting.
20586 Defaults to @samp{#t}.
20589 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
20590 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
20591 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
20592 for caching to be used.
20593 Defaults to @samp{0}.
20596 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
20597 Time to live for cached data. After TTL expires the cached record
20598 is no longer used, *except* if the main database lookup returns internal
20599 failure. We also try to handle password changes automatically: If
20600 user's previous authentication was successful, but this one wasn't, the
20601 cache isn't used. For now this works only with plaintext
20603 Defaults to @samp{"1 hour"}.
20606 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
20607 TTL for negative hits (user not found, password mismatch).
20608 0 disables caching them completely.
20609 Defaults to @samp{"1 hour"}.
20612 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
20613 List of realms for SASL authentication mechanisms that need them.
20614 You can leave it empty if you don't want to support multiple realms.
20615 Many clients simply use the first one listed here, so keep the default
20617 Defaults to @samp{()}.
20620 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
20621 Default realm/domain to use if none was specified. This is used for
20622 both SASL realms and appending @@domain to username in plaintext
20624 Defaults to @samp{""}.
20627 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
20628 List of allowed characters in username. If the user-given username
20629 contains a character not listed in here, the login automatically fails.
20630 This is just an extra check to make sure user can't exploit any
20631 potential quote escaping vulnerabilities with SQL/LDAP databases. If
20632 you want to allow all characters, set this value to empty.
20633 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
20636 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
20637 Username character translations before it's looked up from
20638 databases. The value contains series of from -> to characters. For
20639 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
20640 translated to @samp{@@}.
20641 Defaults to @samp{""}.
20644 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
20645 Username formatting before it's looked up from databases. You can
20646 use the standard variables here, e.g.@: %Lu would lowercase the username,
20647 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
20648 change the @samp{@@} into @samp{-AT-}. This translation is done after
20649 @samp{auth-username-translation} changes.
20650 Defaults to @samp{"%Lu"}.
20653 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
20654 If you want to allow master users to log in by specifying the master
20655 username within the normal username string (i.e.@: not using SASL
20656 mechanism's support for it), you can specify the separator character
20657 here. The format is then <username><separator><master username>.
20658 UW-IMAP uses @samp{*} as the separator, so that could be a good
20660 Defaults to @samp{""}.
20663 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
20664 Username to use for users logging in with ANONYMOUS SASL
20666 Defaults to @samp{"anonymous"}.
20669 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
20670 Maximum number of dovecot-auth worker processes. They're used to
20671 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
20672 They're automatically created and destroyed as needed.
20673 Defaults to @samp{30}.
20676 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
20677 Host name to use in GSSAPI principal names. The default is to use
20678 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
20679 allow all keytab entries.
20680 Defaults to @samp{""}.
20683 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
20684 Kerberos keytab to use for the GSSAPI mechanism. Will use the
20685 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
20686 need to change the auth service to run as root to be able to read this
20688 Defaults to @samp{""}.
20691 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
20692 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
20693 and @samp{ntlm-auth} helper.
20694 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
20695 Defaults to @samp{#f}.
20698 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
20699 Path for Samba's @samp{ntlm-auth} helper binary.
20700 Defaults to @samp{"/usr/bin/ntlm_auth"}.
20703 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
20704 Time to delay before replying to failed authentications.
20705 Defaults to @samp{"2 secs"}.
20708 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
20709 Require a valid SSL client certificate or the authentication
20711 Defaults to @samp{#f}.
20714 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
20715 Take the username from client's SSL certificate, using
20716 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
20718 Defaults to @samp{#f}.
20721 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
20722 List of wanted authentication mechanisms. Supported mechanisms are:
20723 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
20724 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
20725 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
20726 @samp{disable-plaintext-auth} setting.
20729 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
20730 List of IPs or hostnames to all director servers, including ourself.
20731 Ports can be specified as ip:port. The default port is the same as what
20732 director service's @samp{inet-listener} is using.
20733 Defaults to @samp{()}.
20736 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
20737 List of IPs or hostnames to all backend mail servers. Ranges are
20738 allowed too, like 10.0.0.10-10.0.0.30.
20739 Defaults to @samp{()}.
20742 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
20743 How long to redirect users to a specific server after it no longer
20744 has any connections.
20745 Defaults to @samp{"15 min"}.
20748 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
20749 How the username is translated before being hashed. Useful values
20750 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
20751 are shared within domain.
20752 Defaults to @samp{"%Lu"}.
20755 @deftypevr {@code{dovecot-configuration} parameter} string log-path
20756 Log file to use for error messages. @samp{syslog} logs to syslog,
20757 @samp{/dev/stderr} logs to stderr.
20758 Defaults to @samp{"syslog"}.
20761 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
20762 Log file to use for informational messages. Defaults to
20764 Defaults to @samp{""}.
20767 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
20768 Log file to use for debug messages. Defaults to
20769 @samp{info-log-path}.
20770 Defaults to @samp{""}.
20773 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
20774 Syslog facility to use if you're logging to syslog. Usually if you
20775 don't want to use @samp{mail}, you'll use local0..local7. Also other
20776 standard facilities are supported.
20777 Defaults to @samp{"mail"}.
20780 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
20781 Log unsuccessful authentication attempts and the reasons why they
20783 Defaults to @samp{#f}.
20786 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
20787 In case of password mismatches, log the attempted password. Valid
20788 values are no, plain and sha1. sha1 can be useful for detecting brute
20789 force password attempts vs. user simply trying the same password over
20790 and over again. You can also truncate the value to n chars by appending
20791 ":n" (e.g.@: sha1:6).
20792 Defaults to @samp{"no"}.
20795 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
20796 Even more verbose logging for debugging purposes. Shows for example
20798 Defaults to @samp{#f}.
20801 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
20802 In case of password mismatches, log the passwords and used scheme so
20803 the problem can be debugged. Enabling this also enables
20805 Defaults to @samp{#f}.
20808 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
20809 Enable mail process debugging. This can help you figure out why
20810 Dovecot isn't finding your mails.
20811 Defaults to @samp{#f}.
20814 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
20815 Show protocol level SSL errors.
20816 Defaults to @samp{#f}.
20819 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
20820 Prefix for each line written to log file. % codes are in
20821 strftime(3) format.
20822 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
20825 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
20826 List of elements we want to log. The elements which have a
20827 non-empty variable value are joined together to form a comma-separated
20831 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
20832 Login log format. %s contains @samp{login-log-format-elements}
20833 string, %$ contains the data we want to log.
20834 Defaults to @samp{"%$: %s"}.
20837 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
20838 Log prefix for mail processes. See doc/wiki/Variables.txt for list
20839 of possible variables you can use.
20840 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
20843 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
20844 Format to use for logging mail deliveries. You can use variables:
20847 Delivery status message (e.g.@: @samp{saved to INBOX})
20859 Defaults to @samp{"msgid=%m: %$"}.
20862 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
20863 Location for users' mailboxes. The default is empty, which means
20864 that Dovecot tries to find the mailboxes automatically. This won't work
20865 if the user doesn't yet have any mail, so you should explicitly tell
20866 Dovecot the full location.
20868 If you're using mbox, giving a path to the INBOX
20869 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
20870 where the other mailboxes are kept. This is called the @emph{root mail
20871 directory}, and it must be the first path given in the
20872 @samp{mail-location} setting.
20874 There are a few special variables you can use, e.g.:
20880 user part in user@@domain, same as %u if there's no domain
20882 domain part in user@@domain, empty if there's no domain
20887 See doc/wiki/Variables.txt for full list. Some examples:
20889 @item maildir:~/Maildir
20890 @item mbox:~/mail:INBOX=/var/mail/%u
20891 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
20893 Defaults to @samp{""}.
20896 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
20897 System user and group used to access mails. If you use multiple,
20898 userdb can override these by returning uid or gid fields. You can use
20899 either numbers or names. <doc/wiki/UserIds.txt>.
20900 Defaults to @samp{""}.
20903 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
20905 Defaults to @samp{""}.
20908 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
20909 Group to enable temporarily for privileged operations. Currently
20910 this is used only with INBOX when either its initial creation or
20911 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
20913 Defaults to @samp{""}.
20916 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
20917 Grant access to these supplementary groups for mail processes.
20918 Typically these are used to set up access to shared mailboxes. Note
20919 that it may be dangerous to set these if users can create symlinks
20920 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
20921 could allow a user to delete others' mailboxes, or @code{ln -s
20922 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
20926 @deftypevr {@code{dovecot-configuration} parameter} string mail-attribute-dict
20927 The location of a dictionary used to store @code{IMAP METADATA}
20928 as defined by @uref{https://tools.ietf.org/html/rfc5464, RFC@tie{}5464}.
20930 The IMAP METADATA commands are available only if the ``imap''
20931 protocol configuration's @code{imap-metadata?} field is @samp{#t}.
20933 Defaults to @samp{""}.
20937 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
20938 Allow full file system access to clients. There's no access checks
20939 other than what the operating system does for the active UID/GID@. It
20940 works with both maildir and mboxes, allowing you to prefix mailboxes
20941 names with e.g.@: @file{/path/} or @file{~user/}.
20942 Defaults to @samp{#f}.
20945 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
20946 Don't use @code{mmap()} at all. This is required if you store indexes to
20947 shared file systems (NFS or clustered file system).
20948 Defaults to @samp{#f}.
20951 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
20952 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
20953 supports @samp{O_EXCL} since version 3, so this should be safe to use
20954 nowadays by default.
20955 Defaults to @samp{#t}.
20958 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
20959 When to use fsync() or fdatasync() calls:
20962 Whenever necessary to avoid losing important data
20964 Useful with e.g.@: NFS when @code{write()}s are delayed
20966 Never use it (best performance, but crashes can lose data).
20968 Defaults to @samp{"optimized"}.
20971 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
20972 Mail storage exists in NFS@. Set this to yes to make Dovecot flush
20973 NFS caches whenever needed. If you're using only a single mail server
20975 Defaults to @samp{#f}.
20978 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
20979 Mail index files also exist in NFS@. Setting this to yes requires
20980 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
20981 Defaults to @samp{#f}.
20984 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
20985 Locking method for index files. Alternatives are fcntl, flock and
20986 dotlock. Dotlocking uses some tricks which may create more disk I/O
20987 than other locking methods. NFS users: flock doesn't work, remember to
20988 change @samp{mmap-disable}.
20989 Defaults to @samp{"fcntl"}.
20992 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
20993 Directory in which LDA/LMTP temporarily stores incoming mails >128
20995 Defaults to @samp{"/tmp"}.
20998 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
20999 Valid UID range for users. This is mostly to make sure that users can't
21000 log in as daemons or other system users. Note that denying root logins is
21001 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
21003 Defaults to @samp{500}.
21006 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
21008 Defaults to @samp{0}.
21011 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
21012 Valid GID range for users. Users having non-valid GID as primary group ID
21013 aren't allowed to log in. If user belongs to supplementary groups with
21014 non-valid GIDs, those groups are not set.
21015 Defaults to @samp{1}.
21018 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
21020 Defaults to @samp{0}.
21023 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
21024 Maximum allowed length for mail keyword name. It's only forced when
21025 trying to create new keywords.
21026 Defaults to @samp{50}.
21029 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
21030 List of directories under which chrooting is allowed for mail
21031 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
21032 too). This setting doesn't affect @samp{login-chroot}
21033 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
21034 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
21035 which local users can modify, that may lead to root exploit. Usually
21036 this should be done only if you don't allow shell access for users.
21037 <doc/wiki/Chrooting.txt>.
21038 Defaults to @samp{()}.
21041 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
21042 Default chroot directory for mail processes. This can be overridden
21043 for specific users in user database by giving @samp{/./} in user's home
21044 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
21045 there is no real need to do chrooting, Dovecot doesn't allow users to
21046 access files outside their mail directory anyway. If your home
21047 directories are prefixed with the chroot directory, append @samp{/.} to
21048 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
21049 Defaults to @samp{""}.
21052 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
21053 UNIX socket path to master authentication server to find users.
21054 This is used by imap (for shared users) and lda.
21055 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
21058 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
21059 Directory where to look up mail plugins.
21060 Defaults to @samp{"/usr/lib/dovecot"}.
21063 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
21064 List of plugins to load for all services. Plugins specific to IMAP,
21065 LDA, etc.@: are added to this list in their own .conf files.
21066 Defaults to @samp{()}.
21069 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
21070 The minimum number of mails in a mailbox before updates are done to
21071 cache file. This allows optimizing Dovecot's behavior to do less disk
21072 writes at the cost of more disk reads.
21073 Defaults to @samp{0}.
21076 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
21077 When IDLE command is running, mailbox is checked once in a while to
21078 see if there are any new mails or other changes. This setting defines
21079 the minimum time to wait between those checks. Dovecot can also use
21080 dnotify, inotify and kqueue to find out immediately when changes
21082 Defaults to @samp{"30 secs"}.
21085 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
21086 Save mails with CR+LF instead of plain LF@. This makes sending those
21087 mails take less CPU, especially with sendfile() syscall with Linux and
21088 FreeBSD@. But it also creates a bit more disk I/O which may just make it
21089 slower. Also note that if other software reads the mboxes/maildirs,
21090 they may handle the extra CRs wrong and cause problems.
21091 Defaults to @samp{#f}.
21094 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
21095 By default LIST command returns all entries in maildir beginning
21096 with a dot. Enabling this option makes Dovecot return only entries
21097 which are directories. This is done by stat()ing each entry, so it
21098 causes more disk I/O.
21099 (For systems setting struct @samp{dirent->d_type} this check is free
21100 and it's done always regardless of this setting).
21101 Defaults to @samp{#f}.
21104 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
21105 When copying a message, do it with hard links whenever possible.
21106 This makes the performance much better, and it's unlikely to have any
21108 Defaults to @samp{#t}.
21111 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
21112 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
21113 directory only when its mtime changes unexpectedly or when we can't find
21114 the mail otherwise.
21115 Defaults to @samp{#f}.
21118 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
21119 Which locking methods to use for locking mbox. There are four
21124 Create <mailbox>.lock file. This is the oldest and most NFS-safe
21125 solution. If you want to use /var/mail/ like directory, the users will
21126 need write access to that directory.
21128 Same as dotlock, but if it fails because of permissions or because there
21129 isn't enough disk space, just skip it.
21131 Use this if possible. Works with NFS too if lockd is used.
21133 May not exist in all systems. Doesn't work with NFS.
21135 May not exist in all systems. Doesn't work with NFS.
21138 You can use multiple locking methods; if you do the order they're declared
21139 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
21140 locking methods as well. Some operating systems don't allow using some of
21141 them simultaneously.
21144 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
21148 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
21149 Maximum time to wait for lock (all of them) before aborting.
21150 Defaults to @samp{"5 mins"}.
21153 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
21154 If dotlock exists but the mailbox isn't modified in any way,
21155 override the lock file after this much time.
21156 Defaults to @samp{"2 mins"}.
21159 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
21160 When mbox changes unexpectedly we have to fully read it to find out
21161 what changed. If the mbox is large this can take a long time. Since
21162 the change is usually just a newly appended mail, it'd be faster to
21163 simply read the new mails. If this setting is enabled, Dovecot does
21164 this but still safely fallbacks to re-reading the whole mbox file
21165 whenever something in mbox isn't how it's expected to be. The only real
21166 downside to this setting is that if some other MUA changes message
21167 flags, Dovecot doesn't notice it immediately. Note that a full sync is
21168 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
21169 Defaults to @samp{#t}.
21172 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
21173 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
21174 EXAMINE, EXPUNGE or CHECK commands. If this is set,
21175 @samp{mbox-dirty-syncs} is ignored.
21176 Defaults to @samp{#f}.
21179 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
21180 Delay writing mbox headers until doing a full write sync (EXPUNGE
21181 and CHECK commands and when closing the mailbox). This is especially
21182 useful for POP3 where clients often delete all mails. The downside is
21183 that our changes aren't immediately visible to other MUAs.
21184 Defaults to @samp{#t}.
21187 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
21188 If mbox size is smaller than this (e.g.@: 100k), don't write index
21189 files. If an index file already exists it's still read, just not
21191 Defaults to @samp{0}.
21194 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
21195 Maximum dbox file size until it's rotated.
21196 Defaults to @samp{10000000}.
21199 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
21200 Maximum dbox file age until it's rotated. Typically in days. Day
21201 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
21203 Defaults to @samp{"1d"}.
21206 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
21207 When creating new mdbox files, immediately preallocate their size to
21208 @samp{mdbox-rotate-size}. This setting currently works only in Linux
21209 with some file systems (ext4, xfs).
21210 Defaults to @samp{#f}.
21213 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
21214 sdbox and mdbox support saving mail attachments to external files,
21215 which also allows single instance storage for them. Other backends
21216 don't support this for now.
21218 WARNING: This feature hasn't been tested much yet. Use at your own risk.
21220 Directory root where to store mail attachments. Disabled, if empty.
21221 Defaults to @samp{""}.
21224 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
21225 Attachments smaller than this aren't saved externally. It's also
21226 possible to write a plugin to disable saving specific attachments
21228 Defaults to @samp{128000}.
21231 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
21232 File system backend to use for saving attachments:
21235 No SiS done by Dovecot (but this might help FS's own deduplication)
21237 SiS with immediate byte-by-byte comparison during saving
21238 @item sis-queue posix
21239 SiS with delayed comparison and deduplication.
21241 Defaults to @samp{"sis posix"}.
21244 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
21245 Hash format to use in attachment filenames. You can add any text and
21246 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
21247 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
21248 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
21249 Defaults to @samp{"%@{sha1@}"}.
21252 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
21254 Defaults to @samp{100}.
21257 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
21259 Defaults to @samp{1000}.
21262 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
21263 Default VSZ (virtual memory size) limit for service processes.
21264 This is mainly intended to catch and kill processes that leak memory
21265 before they eat up everything.
21266 Defaults to @samp{256000000}.
21269 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
21270 Login user is internally used by login processes. This is the most
21271 untrusted user in Dovecot system. It shouldn't have access to anything
21273 Defaults to @samp{"dovenull"}.
21276 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
21277 Internal user is used by unprivileged processes. It should be
21278 separate from login user, so that login processes can't disturb other
21280 Defaults to @samp{"dovecot"}.
21283 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
21284 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
21285 Defaults to @samp{"required"}.
21288 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
21289 PEM encoded X.509 SSL/TLS certificate (public key).
21290 Defaults to @samp{"</etc/dovecot/default.pem"}.
21293 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
21294 PEM encoded SSL/TLS private key. The key is opened before
21295 dropping root privileges, so keep the key file unreadable by anyone but
21297 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
21300 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
21301 If key file is password protected, give the password here.
21302 Alternatively give it when starting dovecot with -p parameter. Since
21303 this file is often world-readable, you may want to place this setting
21304 instead to a different.
21305 Defaults to @samp{""}.
21308 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
21309 PEM encoded trusted certificate authority. Set this only if you
21310 intend to use @samp{ssl-verify-client-cert? #t}. The file should
21311 contain the CA certificate(s) followed by the matching
21312 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
21313 Defaults to @samp{""}.
21316 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
21317 Require that CRL check succeeds for client certificates.
21318 Defaults to @samp{#t}.
21321 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
21322 Request client to send a certificate. If you also want to require
21323 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
21324 Defaults to @samp{#f}.
21327 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
21328 Which field from certificate to use for username. commonName and
21329 x500UniqueIdentifier are the usual choices. You'll also need to set
21330 @samp{auth-ssl-username-from-cert? #t}.
21331 Defaults to @samp{"commonName"}.
21334 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
21335 Minimum SSL protocol version to accept.
21336 Defaults to @samp{"TLSv1"}.
21339 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
21340 SSL ciphers to use.
21341 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
21344 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
21345 SSL crypto device to use, for valid values run "openssl engine".
21346 Defaults to @samp{""}.
21349 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
21350 Address to use when sending rejection mails.
21351 %d expands to recipient domain.
21352 Defaults to @samp{"postmaster@@%d"}.
21355 @deftypevr {@code{dovecot-configuration} parameter} string hostname
21356 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
21357 and in LMTP replies. Default is the system's real hostname@@domain.
21358 Defaults to @samp{""}.
21361 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
21362 If user is over quota, return with temporary failure instead of
21364 Defaults to @samp{#f}.
21367 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
21368 Binary to use for sending mails.
21369 Defaults to @samp{"/usr/sbin/sendmail"}.
21372 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
21373 If non-empty, send mails via this SMTP host[:port] instead of
21375 Defaults to @samp{""}.
21378 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
21379 Subject: header to use for rejection mails. You can use the same
21380 variables as for @samp{rejection-reason} below.
21381 Defaults to @samp{"Rejected: %s"}.
21384 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
21385 Human readable error message for rejection mails. You can use
21398 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
21401 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
21402 Delimiter character between local-part and detail in email
21404 Defaults to @samp{"+"}.
21407 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
21408 Header where the original recipient address (SMTP's RCPT TO:
21409 address) is taken from if not available elsewhere. With dovecot-lda -a
21410 parameter overrides this. A commonly used header for this is
21412 Defaults to @samp{""}.
21415 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
21416 Should saving a mail to a nonexistent mailbox automatically create
21418 Defaults to @samp{#f}.
21421 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
21422 Should automatically created mailboxes be also automatically
21424 Defaults to @samp{#f}.
21427 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
21428 Maximum IMAP command line length. Some clients generate very long
21429 command lines with huge mailboxes, so you may need to raise this if you
21430 get "Too long argument" or "IMAP command line too large" errors
21432 Defaults to @samp{64000}.
21435 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
21436 IMAP logout format string:
21439 total number of bytes read from client
21441 total number of bytes sent to client.
21443 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
21444 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@}"}.
21447 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
21448 Override the IMAP CAPABILITY response. If the value begins with '+',
21449 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
21450 Defaults to @samp{""}.
21453 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
21454 How long to wait between "OK Still here" notifications when client
21456 Defaults to @samp{"2 mins"}.
21459 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
21460 ID field names and values to send to clients. Using * as the value
21461 makes Dovecot use the default value. The following fields have default
21462 values currently: name, version, os, os-version, support-url,
21464 Defaults to @samp{""}.
21467 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
21468 ID fields sent by client to log. * means everything.
21469 Defaults to @samp{""}.
21472 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
21473 Workarounds for various client bugs:
21476 @item delay-newmail
21477 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
21478 CHECK commands. Some clients ignore them otherwise, for example OSX
21479 Mail (<v2.1). Outlook Express breaks more badly though, without this it
21480 may show user "Message no longer in server" errors. Note that OE6
21481 still breaks even with this workaround if synchronization is set to
21484 @item tb-extra-mailbox-sep
21485 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
21486 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
21487 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
21489 @item tb-lsub-flags
21490 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
21491 This makes Thunderbird realize they aren't selectable and show them
21492 greyed out, instead of only later giving "not selectable" popup error.
21494 Defaults to @samp{()}.
21497 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
21498 Host allowed in URLAUTH URLs sent by client. "*" allows all.
21499 Defaults to @samp{""}.
21503 Whew! Lots of configuration options. The nice thing about it though is
21504 that Guix has a complete interface to Dovecot's configuration
21505 language. This allows not only a nice way to declare configurations,
21506 but also offers reflective capabilities as well: users can write code to
21507 inspect and transform configurations from within Scheme.
21509 However, it could be that you just want to get a @code{dovecot.conf} up
21510 and running. In that case, you can pass an
21511 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
21512 @code{dovecot-service}. As its name indicates, an opaque configuration
21513 does not have easy reflective capabilities.
21515 Available @code{opaque-dovecot-configuration} fields are:
21517 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
21518 The dovecot package.
21521 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
21522 The contents of the @code{dovecot.conf}, as a string.
21525 For example, if your @code{dovecot.conf} is just the empty string, you
21526 could instantiate a dovecot service like this:
21529 (dovecot-service #:config
21530 (opaque-dovecot-configuration
21534 @subsubheading OpenSMTPD Service
21536 @deffn {Scheme Variable} opensmtpd-service-type
21537 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
21538 service, whose value should be an @code{opensmtpd-configuration} object
21539 as in this example:
21542 (service opensmtpd-service-type
21543 (opensmtpd-configuration
21544 (config-file (local-file "./my-smtpd.conf"))))
21548 @deftp {Data Type} opensmtpd-configuration
21549 Data type representing the configuration of opensmtpd.
21552 @item @code{package} (default: @var{opensmtpd})
21553 Package object of the OpenSMTPD SMTP server.
21555 @item @code{config-file} (default: @code{%default-opensmtpd-file})
21556 File-like object of the OpenSMTPD configuration file to use. By default
21557 it listens on the loopback network interface, and allows for mail from
21558 users and daemons on the local machine, as well as permitting email to
21559 remote servers. Run @command{man smtpd.conf} for more information.
21564 @subsubheading Exim Service
21566 @cindex mail transfer agent (MTA)
21567 @cindex MTA (mail transfer agent)
21570 @deffn {Scheme Variable} exim-service-type
21571 This is the type of the @uref{https://exim.org, Exim} mail transfer
21572 agent (MTA), whose value should be an @code{exim-configuration} object
21573 as in this example:
21576 (service exim-service-type
21577 (exim-configuration
21578 (config-file (local-file "./my-exim.conf"))))
21582 In order to use an @code{exim-service-type} service you must also have a
21583 @code{mail-aliases-service-type} service present in your
21584 @code{operating-system} (even if it has no aliases).
21586 @deftp {Data Type} exim-configuration
21587 Data type representing the configuration of exim.
21590 @item @code{package} (default: @var{exim})
21591 Package object of the Exim server.
21593 @item @code{config-file} (default: @code{#f})
21594 File-like object of the Exim configuration file to use. If its value is
21595 @code{#f} then use the default configuration file from the package
21596 provided in @code{package}. The resulting configuration file is loaded
21597 after setting the @code{exim_user} and @code{exim_group} configuration
21603 @subsubheading Getmail service
21608 @deffn {Scheme Variable} getmail-service-type
21609 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
21610 mail retriever, whose value should be an @code{getmail-configuration}.
21613 Available @code{getmail-configuration} fields are:
21615 @deftypevr {@code{getmail-configuration} parameter} symbol name
21616 A symbol to identify the getmail service.
21618 Defaults to @samp{"unset"}.
21622 @deftypevr {@code{getmail-configuration} parameter} package package
21623 The getmail package to use.
21627 @deftypevr {@code{getmail-configuration} parameter} string user
21628 The user to run getmail as.
21630 Defaults to @samp{"getmail"}.
21634 @deftypevr {@code{getmail-configuration} parameter} string group
21635 The group to run getmail as.
21637 Defaults to @samp{"getmail"}.
21641 @deftypevr {@code{getmail-configuration} parameter} string directory
21642 The getmail directory to use.
21644 Defaults to @samp{"/var/lib/getmail/default"}.
21648 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
21649 The getmail configuration file to use.
21651 Available @code{getmail-configuration-file} fields are:
21653 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
21654 What mail account to retrieve mail from, and how to access that account.
21656 Available @code{getmail-retriever-configuration} fields are:
21658 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
21659 The type of mail retriever to use. Valid values include @samp{passwd}
21662 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
21666 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
21667 Username to login to the mail server with.
21669 Defaults to @samp{unset}.
21673 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
21674 Username to login to the mail server with.
21676 Defaults to @samp{unset}.
21680 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
21681 Port number to connect to.
21683 Defaults to @samp{#f}.
21687 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
21688 Override fields from passwd.
21690 Defaults to @samp{""}.
21694 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
21695 Override fields from passwd.
21697 Defaults to @samp{()}.
21701 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
21702 PEM-formatted key file to use for the TLS negotiation.
21704 Defaults to @samp{""}.
21708 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
21709 PEM-formatted certificate file to use for the TLS negotiation.
21711 Defaults to @samp{""}.
21715 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
21716 CA certificates to use.
21718 Defaults to @samp{""}.
21722 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
21723 Extra retriever parameters.
21725 Defaults to @samp{()}.
21731 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
21732 What to do with retrieved messages.
21734 Available @code{getmail-destination-configuration} fields are:
21736 @deftypevr {@code{getmail-destination-configuration} parameter} string type
21737 The type of mail destination. Valid values include @samp{Maildir},
21738 @samp{Mboxrd} and @samp{MDA_external}.
21740 Defaults to @samp{unset}.
21744 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
21745 The path option for the mail destination. The behaviour depends on the
21748 Defaults to @samp{""}.
21752 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
21753 Extra destination parameters
21755 Defaults to @samp{()}.
21761 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
21764 Available @code{getmail-options-configuration} fields are:
21766 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
21767 If set to @samp{0}, getmail will only print warnings and errors. A
21768 value of @samp{1} means that messages will be printed about retrieving
21769 and deleting messages. If set to @samp{2}, getmail will print messages
21770 about each of its actions.
21772 Defaults to @samp{1}.
21776 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
21777 If true, getmail will retrieve all available messages. Otherwise it
21778 will only retrieve messages it hasn't seen previously.
21780 Defaults to @samp{#t}.
21784 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
21785 If set to true, messages will be deleted from the server after
21786 retrieving and successfully delivering them. Otherwise, messages will
21787 be left on the server.
21789 Defaults to @samp{#f}.
21793 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
21794 Getmail will delete messages this number of days after seeing them, if
21795 they have been delivered. This means messages will be left on the
21796 server this number of days after delivering them. A value of @samp{0}
21797 disabled this feature.
21799 Defaults to @samp{0}.
21803 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
21804 Delete messages larger than this of bytes after retrieving them, even if
21805 the delete and delete-after options are disabled. A value of @samp{0}
21806 disables this feature.
21808 Defaults to @samp{0}.
21812 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
21813 Retrieve messages totalling up to this number of bytes before closing
21814 the session with the server. A value of @samp{0} disables this feature.
21816 Defaults to @samp{0}.
21820 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
21821 Don't retrieve messages larger than this number of bytes. A value of
21822 @samp{0} disables this feature.
21824 Defaults to @samp{0}.
21828 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
21829 If true, getmail will add a Delivered-To header to messages.
21831 Defaults to @samp{#t}.
21835 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
21836 If set, getmail adds a Received header to the messages.
21838 Defaults to @samp{#t}.
21842 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
21843 Getmail will record a log of its actions to the named file. A value of
21844 @samp{""} disables this feature.
21846 Defaults to @samp{""}.
21850 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
21851 If true, getmail will record a log of its actions using the system
21854 Defaults to @samp{#f}.
21858 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
21859 If true, getmail will log information about messages not retrieved and
21860 the reason for not retrieving them, as well as starting and ending
21863 Defaults to @samp{#f}.
21867 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
21868 Extra options to include.
21870 Defaults to @samp{()}.
21878 @deftypevr {@code{getmail-configuration} parameter} list idle
21879 A list of mailboxes that getmail should wait on the server for new mail
21880 notifications. This depends on the server supporting the IDLE
21883 Defaults to @samp{()}.
21887 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
21888 Environment variables to set for getmail.
21890 Defaults to @samp{()}.
21894 @subsubheading Mail Aliases Service
21896 @cindex email aliases
21897 @cindex aliases, for email addresses
21899 @deffn {Scheme Variable} mail-aliases-service-type
21900 This is the type of the service which provides @code{/etc/aliases},
21901 specifying how to deliver mail to users on this system.
21904 (service mail-aliases-service-type
21905 '(("postmaster" "bob")
21906 ("bob" "bob@@example.com" "bob@@example2.com")))
21910 The configuration for a @code{mail-aliases-service-type} service is an
21911 association list denoting how to deliver mail that comes to this
21912 system. Each entry is of the form @code{(alias addresses ...)}, with
21913 @code{alias} specifying the local alias and @code{addresses} specifying
21914 where to deliver this user's mail.
21916 The aliases aren't required to exist as users on the local system. In
21917 the above example, there doesn't need to be a @code{postmaster} entry in
21918 the @code{operating-system}'s @code{user-accounts} in order to deliver
21919 the @code{postmaster} mail to @code{bob} (which subsequently would
21920 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
21922 @subsubheading GNU Mailutils IMAP4 Daemon
21923 @cindex GNU Mailutils IMAP4 Daemon
21925 @deffn {Scheme Variable} imap4d-service-type
21926 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
21927 mailutils, GNU Mailutils Manual}), whose value should be an
21928 @code{imap4d-configuration} object as in this example:
21931 (service imap4d-service-type
21932 (imap4d-configuration
21933 (config-file (local-file "imap4d.conf"))))
21937 @deftp {Data Type} imap4d-configuration
21938 Data type representing the configuration of @command{imap4d}.
21941 @item @code{package} (default: @code{mailutils})
21942 The package that provides @command{imap4d}.
21944 @item @code{config-file} (default: @code{%default-imap4d-config-file})
21945 File-like object of the configuration file to use, by default it will listen
21946 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
21947 Mailutils Manual}, for details.
21952 @subsubheading Radicale Service
21956 @deffn {Scheme Variable} radicale-service-type
21957 This is the type of the @uref{https://radicale.org, Radicale} CalDAV/CardDAV
21958 server whose value should be a @code{radicale-configuration}.
21961 @deftp {Data Type} radicale-configuration
21962 Data type representing the configuration of @command{radicale}.
21965 @item @code{package} (default: @code{radicale})
21966 The package that provides @command{radicale}.
21968 @item @code{config-file} (default: @code{%default-radicale-config-file})
21969 File-like object of the configuration file to use, by default it will listen
21970 on TCP port 5232 of @code{localhost} and use the @code{htpasswd} file at
21971 @file{/var/lib/radicale/users} with no (@code{plain}) encryption.
21976 @node Messaging Services
21977 @subsection Messaging Services
21982 The @code{(gnu services messaging)} module provides Guix service
21983 definitions for messaging services. Currently it provides the following
21986 @subsubheading Prosody Service
21988 @deffn {Scheme Variable} prosody-service-type
21989 This is the type for the @uref{https://prosody.im, Prosody XMPP
21990 communication server}. Its value must be a @code{prosody-configuration}
21991 record as in this example:
21994 (service prosody-service-type
21995 (prosody-configuration
21996 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
21999 (int-component-configuration
22000 (hostname "conference.example.net")
22002 (mod-muc (mod-muc-configuration)))))
22005 (virtualhost-configuration
22006 (domain "example.net"))))))
22009 See below for details about @code{prosody-configuration}.
22013 By default, Prosody does not need much configuration. Only one
22014 @code{virtualhosts} field is needed: it specifies the domain you wish
22017 You can perform various sanity checks on the generated configuration
22018 with the @code{prosodyctl check} command.
22020 Prosodyctl will also help you to import certificates from the
22021 @code{letsencrypt} directory so that the @code{prosody} user can access
22022 them. See @url{https://prosody.im/doc/letsencrypt}.
22025 prosodyctl --root cert import /etc/letsencrypt/live
22028 The available configuration parameters follow. Each parameter
22029 definition is preceded by its type; for example, @samp{string-list foo}
22030 indicates that the @code{foo} parameter should be specified as a list of
22031 strings. Types starting with @code{maybe-} denote parameters that won't
22032 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
22034 There is also a way to specify the configuration as a string, if you
22035 have an old @code{prosody.cfg.lua} file that you want to port over from
22036 some other system; see the end for more details.
22038 The @code{file-object} type designates either a file-like object
22039 (@pxref{G-Expressions, file-like objects}) or a file name.
22041 @c The following documentation was initially generated by
22042 @c (generate-documentation) in (gnu services messaging). Manually maintained
22043 @c documentation is better, so we shouldn't hesitate to edit below as
22044 @c needed. However if the change you want to make to this documentation
22045 @c can be done in an automated way, it's probably easier to change
22046 @c (generate-documentation) than to make it below and have to deal with
22047 @c the churn as Prosody updates.
22049 Available @code{prosody-configuration} fields are:
22051 @deftypevr {@code{prosody-configuration} parameter} package prosody
22052 The Prosody package.
22055 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
22056 Location of the Prosody data storage directory. See
22057 @url{https://prosody.im/doc/configure}.
22058 Defaults to @samp{"/var/lib/prosody"}.
22061 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
22062 Additional plugin directories. They are searched in all the specified
22063 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
22064 Defaults to @samp{()}.
22067 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
22068 Every virtual host and component needs a certificate so that clients and
22069 servers can securely verify its identity. Prosody will automatically load
22070 certificates/keys from the directory specified here.
22071 Defaults to @samp{"/etc/prosody/certs"}.
22074 @deftypevr {@code{prosody-configuration} parameter} string-list admins
22075 This is a list of accounts that are admins for the server. Note that you
22076 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
22077 @url{https://prosody.im/doc/creating_accounts}.
22078 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
22079 Defaults to @samp{()}.
22082 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
22083 Enable use of libevent for better performance under high load. See
22084 @url{https://prosody.im/doc/libevent}.
22085 Defaults to @samp{#f}.
22088 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
22089 This is the list of modules Prosody will load on startup. It looks for
22090 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
22091 Documentation on modules can be found at:
22092 @url{https://prosody.im/doc/modules}.
22093 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
22096 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
22097 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
22098 should you want to disable them then add them to this list.
22099 Defaults to @samp{()}.
22102 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
22103 Path to a text file where the shared groups are defined. If this path is
22104 empty then @samp{mod_groups} does nothing. See
22105 @url{https://prosody.im/doc/modules/mod_groups}.
22106 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
22109 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
22110 Disable account creation by default, for security. See
22111 @url{https://prosody.im/doc/creating_accounts}.
22112 Defaults to @samp{#f}.
22115 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
22116 These are the SSL/TLS-related settings. Most of them are disabled so to
22117 use Prosody's defaults. If you do not completely understand these options, do
22118 not add them to your config, it is easy to lower the security of your server
22119 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
22121 Available @code{ssl-configuration} fields are:
22123 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
22124 This determines what handshake to use.
22127 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
22128 Path to your private key file.
22131 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
22132 Path to your certificate file.
22135 @deftypevr {@code{ssl-configuration} parameter} file-object capath
22136 Path to directory containing root certificates that you wish Prosody to
22137 trust when verifying the certificates of remote servers.
22138 Defaults to @samp{"/etc/ssl/certs"}.
22141 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
22142 Path to a file containing root certificates that you wish Prosody to trust.
22143 Similar to @code{capath} but with all certificates concatenated together.
22146 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
22147 A list of verification options (these mostly map to OpenSSL's
22148 @code{set_verify()} flags).
22151 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
22152 A list of general options relating to SSL/TLS@. These map to OpenSSL's
22153 @code{set_options()}. For a full list of options available in LuaSec, see the
22157 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
22158 How long a chain of certificate authorities to check when looking for a
22159 trusted root certificate.
22162 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
22163 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
22164 clients, and in what order.
22167 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
22168 A path to a file containing parameters for Diffie-Hellman key exchange. You
22169 can create such a file with:
22170 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
22173 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
22174 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
22175 @samp{"secp384r1"}.
22178 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
22179 A list of ``extra'' verification options.
22182 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
22183 Password for encrypted private keys.
22188 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
22189 Whether to force all client-to-server connections to be encrypted or not.
22190 See @url{https://prosody.im/doc/modules/mod_tls}.
22191 Defaults to @samp{#f}.
22194 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
22195 Set of mechanisms that will never be offered. See
22196 @url{https://prosody.im/doc/modules/mod_saslauth}.
22197 Defaults to @samp{("DIGEST-MD5")}.
22200 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
22201 Whether to force all server-to-server connections to be encrypted or not.
22202 See @url{https://prosody.im/doc/modules/mod_tls}.
22203 Defaults to @samp{#f}.
22206 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
22207 Whether to require encryption and certificate authentication. This
22208 provides ideal security, but requires servers you communicate with to support
22209 encryption AND present valid, trusted certificates. See
22210 @url{https://prosody.im/doc/s2s#security}.
22211 Defaults to @samp{#f}.
22214 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
22215 Many servers don't support encryption or have invalid or self-signed
22216 certificates. You can list domains here that will not be required to
22217 authenticate using certificates. They will be authenticated using DNS@. See
22218 @url{https://prosody.im/doc/s2s#security}.
22219 Defaults to @samp{()}.
22222 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
22223 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
22224 valid certificates for some domains by specifying a list here. See
22225 @url{https://prosody.im/doc/s2s#security}.
22226 Defaults to @samp{()}.
22229 @deftypevr {@code{prosody-configuration} parameter} string authentication
22230 Select the authentication backend to use. The default provider stores
22231 passwords in plaintext and uses Prosody's configured data storage to store the
22232 authentication data. If you do not trust your server please see
22233 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
22234 about using the hashed backend. See also
22235 @url{https://prosody.im/doc/authentication}
22236 Defaults to @samp{"internal_plain"}.
22239 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
22240 Set logging options. Advanced logging configuration is not yet supported
22241 by the Prosody service. See @url{https://prosody.im/doc/logging}.
22242 Defaults to @samp{"*syslog"}.
22245 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
22246 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
22247 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
22250 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
22251 Maximum allowed size of the HTTP body (in bytes).
22254 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
22255 Some modules expose their own URL in various ways. This URL is built
22256 from the protocol, host and port used. If Prosody sits behind a proxy, the
22257 public URL will be @code{http-external-url} instead. See
22258 @url{https://prosody.im/doc/http#external_url}.
22261 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
22262 A host in Prosody is a domain on which user accounts can be created. For
22263 example if you want your users to have addresses like
22264 @samp{"john.smith@@example.com"} then you need to add a host
22265 @samp{"example.com"}. All options in this list will apply only to this host.
22267 Note: the name @emph{virtual} host is used in configuration to avoid confusion with
22268 the actual physical host that Prosody is installed on. A single Prosody
22269 instance can serve many domains, each one defined as a VirtualHost entry in
22270 Prosody's configuration. Conversely a server that hosts a single domain would
22271 have just one VirtualHost entry.
22273 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
22275 Available @code{virtualhost-configuration} fields are:
22277 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:
22278 @deftypevr {@code{virtualhost-configuration} parameter} string domain
22279 Domain you wish Prosody to serve.
22284 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
22285 Components are extra services on a server which are available to clients,
22286 usually on a subdomain of the main server (such as
22287 @samp{"mycomponent.example.com"}). Example components might be chatroom
22288 servers, user directories, or gateways to other protocols.
22290 Internal components are implemented with Prosody-specific plugins. To add an
22291 internal component, you simply fill the hostname field, and the plugin you wish
22292 to use for the component.
22294 See @url{https://prosody.im/doc/components}.
22295 Defaults to @samp{()}.
22297 Available @code{int-component-configuration} fields are:
22299 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:
22300 @deftypevr {@code{int-component-configuration} parameter} string hostname
22301 Hostname of the component.
22304 @deftypevr {@code{int-component-configuration} parameter} string plugin
22305 Plugin you wish to use for the component.
22308 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
22309 Multi-user chat (MUC) is Prosody's module for allowing you to create
22310 hosted chatrooms/conferences for XMPP users.
22312 General information on setting up and using multi-user chatrooms can be found
22313 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
22314 which you should read if you are new to XMPP chatrooms.
22316 See also @url{https://prosody.im/doc/modules/mod_muc}.
22318 Available @code{mod-muc-configuration} fields are:
22320 @deftypevr {@code{mod-muc-configuration} parameter} string name
22321 The name to return in service discovery responses.
22322 Defaults to @samp{"Prosody Chatrooms"}.
22325 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
22326 If @samp{#t}, this will only allow admins to create new chatrooms.
22327 Otherwise anyone can create a room. The value @samp{"local"} restricts room
22328 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
22329 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
22330 restricts to service administrators only.
22331 Defaults to @samp{#f}.
22334 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
22335 Maximum number of history messages that will be sent to the member that has
22336 just joined the room.
22337 Defaults to @samp{20}.
22344 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
22345 External components use XEP-0114, which most standalone components
22346 support. To add an external component, you simply fill the hostname field. See
22347 @url{https://prosody.im/doc/components}.
22348 Defaults to @samp{()}.
22350 Available @code{ext-component-configuration} fields are:
22352 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:
22353 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
22354 Password which the component will use to log in.
22357 @deftypevr {@code{ext-component-configuration} parameter} string hostname
22358 Hostname of the component.
22363 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
22364 Port(s) Prosody listens on for component connections.
22365 Defaults to @samp{(5347)}.
22368 @deftypevr {@code{prosody-configuration} parameter} string component-interface
22369 Interface Prosody listens on for component connections.
22370 Defaults to @samp{"127.0.0.1"}.
22373 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
22374 Raw content that will be added to the configuration file.
22377 It could be that you just want to get a @code{prosody.cfg.lua}
22378 up and running. In that case, you can pass an
22379 @code{opaque-prosody-configuration} record as the value of
22380 @code{prosody-service-type}. As its name indicates, an opaque configuration
22381 does not have easy reflective capabilities.
22382 Available @code{opaque-prosody-configuration} fields are:
22384 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
22385 The prosody package.
22388 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
22389 The contents of the @code{prosody.cfg.lua} to use.
22392 For example, if your @code{prosody.cfg.lua} is just the empty
22393 string, you could instantiate a prosody service like this:
22396 (service prosody-service-type
22397 (opaque-prosody-configuration
22398 (prosody.cfg.lua "")))
22401 @c end of Prosody auto-generated documentation
22403 @subsubheading BitlBee Service
22405 @cindex IRC (Internet Relay Chat)
22406 @cindex IRC gateway
22407 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
22408 interface to a variety of messaging protocols such as XMPP.
22410 @defvr {Scheme Variable} bitlbee-service-type
22411 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
22412 gateway daemon. Its value is a @code{bitlbee-configuration} (see
22415 To have BitlBee listen on port 6667 on localhost, add this line to your
22419 (service bitlbee-service-type)
22423 @deftp {Data Type} bitlbee-configuration
22424 This is the configuration for BitlBee, with the following fields:
22427 @item @code{interface} (default: @code{"127.0.0.1"})
22428 @itemx @code{port} (default: @code{6667})
22429 Listen on the network interface corresponding to the IP address
22430 specified in @var{interface}, on @var{port}.
22432 When @var{interface} is @code{127.0.0.1}, only local clients can
22433 connect; when it is @code{0.0.0.0}, connections can come from any
22434 networking interface.
22436 @item @code{bitlbee} (default: @code{bitlbee})
22437 The BitlBee package to use.
22439 @item @code{plugins} (default: @code{'()})
22440 List of plugin packages to use---e.g., @code{bitlbee-discord}.
22442 @item @code{extra-settings} (default: @code{""})
22443 Configuration snippet added as-is to the BitlBee configuration file.
22447 @subsubheading Quassel Service
22449 @cindex IRC (Internet Relay Chat)
22450 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
22451 meaning that one or more clients can attach to and detach from the
22454 @defvr {Scheme Variable} quassel-service-type
22455 This is the service type for the @url{https://quassel-irc.org/,Quassel}
22456 IRC backend daemon. Its value is a @code{quassel-configuration}
22460 @deftp {Data Type} quassel-configuration
22461 This is the configuration for Quassel, with the following fields:
22464 @item @code{quassel} (default: @code{quassel})
22465 The Quassel package to use.
22467 @item @code{interface} (default: @code{"::,0.0.0.0"})
22468 @item @code{port} (default: @code{4242})
22469 Listen on the network interface(s) corresponding to the IPv4 or IPv6
22470 interfaces specified in the comma delimited @var{interface}, on
22473 @item @code{loglevel} (default: @code{"Info"})
22474 The level of logging desired. Accepted values are Debug, Info, Warning
22479 @node Telephony Services
22480 @subsection Telephony Services
22482 @cindex Murmur (VoIP server)
22483 @cindex VoIP server
22484 This section describes how to set up and run a Murmur server. Murmur is
22485 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
22488 @deftp {Data Type} murmur-configuration
22489 The service type for the Murmur server. An example configuration can
22493 (service murmur-service-type
22494 (murmur-configuration
22496 "Welcome to this Mumble server running on Guix!")
22497 (cert-required? #t) ;disallow text password logins
22498 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
22499 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
22502 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
22503 password with the command that is printed during the activation phase.
22505 It is recommended to register a normal Mumble user account
22506 and grant it admin or moderator rights.
22507 You can use the @code{mumble} client to
22508 login as new normal user, register yourself, and log out.
22509 For the next step login with the name @code{SuperUser} use
22510 the @code{SuperUser} password that you set previously,
22511 and grant your newly registered mumble user administrator or moderator
22512 rights and create some channels.
22514 Available @code{murmur-configuration} fields are:
22517 @item @code{package} (default: @code{mumble})
22518 Package that contains @code{bin/murmurd}.
22520 @item @code{user} (default: @code{"murmur"})
22521 User who will run the Murmur server.
22523 @item @code{group} (default: @code{"murmur"})
22524 Group of the user who will run the murmur server.
22526 @item @code{port} (default: @code{64738})
22527 Port on which the server will listen.
22529 @item @code{welcome-text} (default: @code{""})
22530 Welcome text sent to clients when they connect.
22532 @item @code{server-password} (default: @code{""})
22533 Password the clients have to enter in order to connect.
22535 @item @code{max-users} (default: @code{100})
22536 Maximum of users that can be connected to the server at once.
22538 @item @code{max-user-bandwidth} (default: @code{#f})
22539 Maximum voice traffic a user can send per second.
22541 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
22542 File name of the sqlite database.
22543 The service's user will become the owner of the directory.
22545 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
22546 File name of the log file.
22547 The service's user will become the owner of the directory.
22549 @item @code{autoban-attempts} (default: @code{10})
22550 Maximum number of logins a user can make in @code{autoban-timeframe}
22551 without getting auto banned for @code{autoban-time}.
22553 @item @code{autoban-timeframe} (default: @code{120})
22554 Timeframe for autoban in seconds.
22556 @item @code{autoban-time} (default: @code{300})
22557 Amount of time in seconds for which a client gets banned
22558 when violating the autoban limits.
22560 @item @code{opus-threshold} (default: @code{100})
22561 Percentage of clients that need to support opus
22562 before switching over to opus audio codec.
22564 @item @code{channel-nesting-limit} (default: @code{10})
22565 How deep channels can be nested at maximum.
22567 @item @code{channelname-regex} (default: @code{#f})
22568 A string in form of a Qt regular expression that channel names must conform to.
22570 @item @code{username-regex} (default: @code{#f})
22571 A string in form of a Qt regular expression that user names must conform to.
22573 @item @code{text-message-length} (default: @code{5000})
22574 Maximum size in bytes that a user can send in one text chat message.
22576 @item @code{image-message-length} (default: @code{(* 128 1024)})
22577 Maximum size in bytes that a user can send in one image message.
22579 @item @code{cert-required?} (default: @code{#f})
22580 If it is set to @code{#t} clients that use weak password authentication
22581 will not be accepted. Users must have completed the certificate wizard to join.
22583 @item @code{remember-channel?} (default: @code{#f})
22584 Should murmur remember the last channel each user was in when they disconnected
22585 and put them into the remembered channel when they rejoin.
22587 @item @code{allow-html?} (default: @code{#f})
22588 Should html be allowed in text messages, user comments, and channel descriptions.
22590 @item @code{allow-ping?} (default: @code{#f})
22591 Setting to true exposes the current user count, the maximum user count, and
22592 the server's maximum bandwidth per client to unauthenticated users. In the
22593 Mumble client, this information is shown in the Connect dialog.
22595 Disabling this setting will prevent public listing of the server.
22597 @item @code{bonjour?} (default: @code{#f})
22598 Should the server advertise itself in the local network through the bonjour protocol.
22600 @item @code{send-version?} (default: @code{#f})
22601 Should the murmur server version be exposed in ping requests.
22603 @item @code{log-days} (default: @code{31})
22604 Murmur also stores logs in the database, which are accessible via RPC.
22605 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
22606 or -1 to disable logging to the database.
22608 @item @code{obfuscate-ips?} (default: @code{#t})
22609 Should logged ips be obfuscated to protect the privacy of users.
22611 @item @code{ssl-cert} (default: @code{#f})
22612 File name of the SSL/TLS certificate used for encrypted connections.
22615 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
22617 @item @code{ssl-key} (default: @code{#f})
22618 Filepath to the ssl private key used for encrypted connections.
22620 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
22623 @item @code{ssl-dh-params} (default: @code{#f})
22624 File name of a PEM-encoded file with Diffie-Hellman parameters
22625 for the SSL/TLS encryption. Alternatively you set it to
22626 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
22627 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
22629 @item @code{ssl-ciphers} (default: @code{#f})
22630 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
22633 This option is specified using
22634 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
22635 OpenSSL cipher list notation}.
22637 It is recommended that you try your cipher string using 'openssl ciphers <string>'
22638 before setting it here, to get a feel for which cipher suites you will get.
22639 After setting this option, it is recommend that you inspect your Murmur log
22640 to ensure that Murmur is using the cipher suites that you expected it to.
22642 Note: Changing this option may impact the backwards compatibility of your
22643 Murmur server, and can remove the ability for older Mumble clients to be able
22646 @item @code{public-registration} (default: @code{#f})
22647 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
22649 You can optionally register your server in the public server list that the
22650 @code{mumble} client shows on startup.
22651 You cannot register your server if you have set a @code{server-password},
22652 or set @code{allow-ping} to @code{#f}.
22654 It might take a few hours until it shows up in the public list.
22656 @item @code{file} (default: @code{#f})
22657 Optional alternative override for this configuration.
22661 @deftp {Data Type} murmur-public-registration-configuration
22662 Configuration for public registration of a murmur service.
22666 This is a display name for your server. Not to be confused with the hostname.
22668 @item @code{password}
22669 A password to identify your registration.
22670 Subsequent updates will need the same password. Don't lose your password.
22673 This should be a @code{http://} or @code{https://} link to your web
22676 @item @code{hostname} (default: @code{#f})
22677 By default your server will be listed by its IP address.
22678 If it is set your server will be linked by this host name instead.
22684 @node File-Sharing Services
22685 @subsection File-Sharing Services
22687 The @code{(gnu services file-sharing)} module provides services that
22688 assist with transferring files over peer-to-peer file-sharing networks.
22690 @subsubheading Transmission Daemon Service
22692 @uref{https://transmissionbt.com/, Transmission} is a flexible
22693 BitTorrent client that offers a variety of graphical and command-line
22694 interfaces. A @code{transmission-daemon-service-type} service provides
22695 Transmission's headless variant, @command{transmission-daemon}, as a
22696 system service, allowing users to share files via BitTorrent even when
22697 they are not logged in.
22699 @deffn {Scheme Variable} transmission-daemon-service-type
22700 The service type for the Transmission Daemon BitTorrent client. Its
22701 value must be a @code{transmission-daemon-configuration} object as in
22705 (service transmission-daemon-service-type
22706 (transmission-daemon-configuration
22707 ;; Restrict access to the RPC ("control") interface
22708 (rpc-authentication-required? #t)
22709 (rpc-username "transmission")
22711 (transmission-password-hash
22712 "transmission" ; desired password
22713 "uKd1uMs9")) ; arbitrary salt value
22715 ;; Accept requests from this and other hosts on the
22717 (rpc-whitelist-enabled? #t)
22718 (rpc-whitelist '("::1" "127.0.0.1" "192.168.0.*"))
22720 ;; Limit bandwidth use during work hours
22721 (alt-speed-down (* 1024 2)) ; 2 MB/s
22722 (alt-speed-up 512) ; 512 kB/s
22724 (alt-speed-time-enabled? #t)
22725 (alt-speed-time-day 'weekdays)
22726 (alt-speed-time-begin
22727 (+ (* 60 8) 30)) ; 8:30 am
22728 (alt-speed-time-end
22729 (+ (* 60 (+ 12 5)) 30)))) ; 5:30 pm
22733 Once the service is started, users can interact with the daemon through
22734 its Web interface (at @code{http://localhost:9091/}) or by using the
22735 @command{transmission-remote} command-line tool, available in the
22736 @code{transmission} package. (Emacs users may want to also consider the
22737 @code{emacs-transmission} package.) Both communicate with the daemon
22738 through its remote procedure call (RPC) interface, which by default is
22739 available to all users on the system; you may wish to change this by
22740 assigning values to the @code{rpc-authentication-required?},
22741 @code{rpc-username} and @code{rpc-password} settings, as shown in the
22742 example above and documented further below.
22744 The value for @code{rpc-password} must be a password hash of the type
22745 generated and used by Transmission clients. This can be copied verbatim
22746 from an existing @file{settings.json} file, if another Transmission
22747 client is already being used. Otherwise, the
22748 @code{transmission-password-hash} and @code{transmission-random-salt}
22749 procedures provided by this module can be used to obtain a suitable hash
22752 @deffn {Scheme Procedure} transmission-password-hash @var{password} @var{salt}
22753 Returns a string containing the result of hashing @var{password}
22754 together with @var{salt}, in the format recognized by Transmission
22755 clients for their @code{rpc-password} configuration setting.
22757 @var{salt} must be an eight-character string. The
22758 @code{transmission-random-salt} procedure can be used to generate a
22759 suitable salt value at random.
22762 @deffn {Scheme Procedure} transmission-random-salt
22763 Returns a string containing a random, eight-character salt value of the
22764 type generated and used by Transmission clients, suitable for passing to
22765 the @code{transmission-password-hash} procedure.
22768 These procedures are accessible from within a Guile REPL started with
22769 the @command{guix repl} command (@pxref{Invoking guix repl}). This is
22770 useful for obtaining a random salt value to provide as the second
22771 parameter to `transmission-password-hash`, as in this example session:
22775 scheme@@(guix-user)> ,use (gnu services file-sharing)
22776 scheme@@(guix-user)> (transmission-random-salt)
22780 Alternatively, a complete password hash can generated in a single step:
22783 scheme@@(guix-user)> (transmission-password-hash "transmission"
22784 (transmission-random-salt))
22785 $2 = "@{c8bbc6d1740cd8dc819a6e25563b67812c1c19c9VtFPfdsX"
22788 The resulting string can be used as-is for the value of
22789 @code{rpc-password}, allowing the password to be kept hidden even in the
22790 operating-system configuration.
22792 Torrent files downloaded by the daemon are directly accessible only to
22793 users in the ``transmission'' user group, who receive read-only access
22794 to the directory specified by the @code{download-dir} configuration
22795 setting (and also the directory specified by @code{incomplete-dir}, if
22796 @code{incomplete-dir-enabled?} is @code{#t}). Downloaded files can be
22797 moved to another directory or deleted altogether using
22798 @command{transmission-remote} with its @code{--move} and
22799 @code{--remove-and-delete} options.
22801 If the @code{watch-dir-enabled?} setting is set to @code{#t}, users in
22802 the ``transmission'' group are able also to place @file{.torrent} files
22803 in the directory specified by @code{watch-dir} to have the corresponding
22804 torrents added by the daemon. (The @code{trash-original-torrent-files?}
22805 setting controls whether the daemon deletes these files after processing
22808 Some of the daemon's configuration settings can be changed temporarily
22809 by @command{transmission-remote} and similar tools. To undo these
22810 changes, use the service's @code{reload} action to have the daemon
22811 reload its settings from disk:
22814 # herd reload transmission-daemon
22817 The full set of available configuration settings is defined by the
22818 @code{transmission-daemon-configuration} data type.
22820 @deftp {Data Type} transmission-daemon-configuration
22821 The data type representing configuration settings for Transmission
22822 Daemon. These correspond directly to the settings recognized by
22823 Transmission clients in their @file{settings.json} file.
22826 @c The following documentation was initially generated by
22827 @c (generate-transmission-daemon-documentation) in (gnu services
22828 @c file-sharing). Manually maintained documentation is better, so we
22829 @c shouldn't hesitate to edit below as needed. However if the change
22830 @c you want to make to this documentation can be done in an automated
22831 @c way, it's probably easier to change (generate-documentation) than to
22832 @c make it below and have to deal with the churn as Transmission Daemon
22835 @c %start of fragment
22837 Available @code{transmission-daemon-configuration} fields are:
22839 @deftypevr {@code{transmission-daemon-configuration} parameter} package transmission
22840 The Transmission package to use.
22844 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer stop-wait-period
22845 The period, in seconds, to wait when stopping the service for
22846 @command{transmission-daemon} to exit before killing its process. This
22847 allows the daemon time to complete its housekeeping and send a final
22848 update to trackers as it shuts down. On slow hosts, or hosts with a
22849 slow network connection, this value may need to be increased.
22851 Defaults to @samp{10}.
22855 @deftypevr {@code{transmission-daemon-configuration} parameter} string download-dir
22856 The directory to which torrent files are downloaded.
22858 Defaults to @samp{"/var/lib/transmission-daemon/downloads"}.
22862 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean incomplete-dir-enabled?
22863 If @code{#t}, files will be held in @code{incomplete-dir} while their
22864 torrent is being downloaded, then moved to @code{download-dir} once the
22865 torrent is complete. Otherwise, files for all torrents (including those
22866 still being downloaded) will be placed in @code{download-dir}.
22868 Defaults to @samp{#f}.
22872 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string incomplete-dir
22873 The directory in which files from incompletely downloaded torrents will
22874 be held when @code{incomplete-dir-enabled?} is @code{#t}.
22876 Defaults to @samp{disabled}.
22880 @deftypevr {@code{transmission-daemon-configuration} parameter} umask umask
22881 The file mode creation mask used for downloaded files. (See the
22882 @command{umask} man page for more information.)
22884 Defaults to @samp{18}.
22888 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rename-partial-files?
22889 When @code{#t}, ``.part'' is appended to the name of partially
22892 Defaults to @samp{#t}.
22896 @deftypevr {@code{transmission-daemon-configuration} parameter} preallocation-mode preallocation
22897 The mode by which space should be preallocated for downloaded files, one
22898 of @code{none}, @code{fast} (or @code{sparse}) and @code{full}.
22899 Specifying @code{full} will minimize disk fragmentation at a cost to
22900 file-creation speed.
22902 Defaults to @samp{fast}.
22906 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean watch-dir-enabled?
22907 If @code{#t}, the directory specified by @code{watch-dir} will be
22908 watched for new @file{.torrent} files and the torrents they describe
22909 added automatically (and the original files removed, if
22910 @code{trash-original-torrent-files?} is @code{#t}).
22912 Defaults to @samp{#f}.
22916 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string watch-dir
22917 The directory to be watched for @file{.torrent} files indicating new
22918 torrents to be added, when @code{watch-dir-enabled} is @code{#t}.
22920 Defaults to @samp{disabled}.
22924 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean trash-original-torrent-files?
22925 When @code{#t}, @file{.torrent} files will be deleted from the watch
22926 directory once their torrent has been added (see
22927 @code{watch-directory-enabled?}).
22929 Defaults to @samp{#f}.
22933 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-down-enabled?
22934 When @code{#t}, the daemon's download speed will be limited to the rate
22935 specified by @code{speed-limit-down}.
22937 Defaults to @samp{#f}.
22941 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-down
22942 The default global-maximum download speed, in kilobytes per second.
22944 Defaults to @samp{100}.
22948 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-up-enabled?
22949 When @code{#t}, the daemon's upload speed will be limited to the rate
22950 specified by @code{speed-limit-up}.
22952 Defaults to @samp{#f}.
22956 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-up
22957 The default global-maximum upload speed, in kilobytes per second.
22959 Defaults to @samp{100}.
22963 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-enabled?
22964 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
22965 @code{alt-speed-up} are used (in place of @code{speed-limit-down} and
22966 @code{speed-limit-up}, if they are enabled) to constrain the daemon's
22967 bandwidth usage. This can be scheduled to occur automatically at
22968 certain times during the week; see @code{alt-speed-time-enabled?}.
22970 Defaults to @samp{#f}.
22974 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-down
22975 The alternate global-maximum download speed, in kilobytes per second.
22977 Defaults to @samp{50}.
22981 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-up
22982 The alternate global-maximum upload speed, in kilobytes per second.
22984 Defaults to @samp{50}.
22988 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-time-enabled?
22989 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
22990 @code{alt-speed-up} will be enabled automatically during the periods
22991 specified by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
22992 @code{alt-time-speed-end}.
22994 Defaults to @samp{#f}.
22998 @deftypevr {@code{transmission-daemon-configuration} parameter} day-list alt-speed-time-day
22999 The days of the week on which the alternate-speed schedule should be
23000 used, specified either as a list of days (@code{sunday}, @code{monday},
23001 and so on) or using one of the symbols @code{weekdays}, @code{weekends}
23004 Defaults to @samp{all}.
23008 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-begin
23009 The time of day at which to enable the alternate speed limits, expressed
23010 as a number of minutes since midnight.
23012 Defaults to @samp{540}.
23016 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-end
23017 The time of day at which to disable the alternate speed limits,
23018 expressed as a number of minutes since midnight.
23020 Defaults to @samp{1020}.
23024 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv4
23025 The IP address at which to listen for peer connections, or ``0.0.0.0''
23026 to listen at all available IP addresses.
23028 Defaults to @samp{"0.0.0.0"}.
23032 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv6
23033 The IPv6 address at which to listen for peer connections, or ``::'' to
23034 listen at all available IPv6 addresses.
23036 Defaults to @samp{"::"}.
23040 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean peer-port-random-on-start?
23041 If @code{#t}, when the daemon starts it will select a port at random on
23042 which to listen for peer connections, from the range specified
23043 (inclusively) by @code{peer-port-random-low} and
23044 @code{peer-port-random-high}. Otherwise, it listens on the port
23045 specified by @code{peer-port}.
23047 Defaults to @samp{#f}.
23051 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-low
23052 The lowest selectable port number when @code{peer-port-random-on-start?}
23055 Defaults to @samp{49152}.
23059 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-high
23060 The highest selectable port number when @code{peer-port-random-on-start}
23063 Defaults to @samp{65535}.
23067 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port
23068 The port on which to listen for peer connections when
23069 @code{peer-port-random-on-start?} is @code{#f}.
23071 Defaults to @samp{51413}.
23075 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean port-forwarding-enabled?
23076 If @code{#t}, the daemon will attempt to configure port-forwarding on an
23077 upstream gateway automatically using @acronym{UPnP} and
23080 Defaults to @samp{#t}.
23084 @deftypevr {@code{transmission-daemon-configuration} parameter} encryption-mode encryption
23085 The encryption preference for peer connections, one of
23086 @code{prefer-unencrypted-connections},
23087 @code{prefer-encrypted-connections} or
23088 @code{require-encrypted-connections}.
23090 Defaults to @samp{prefer-encrypted-connections}.
23094 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string peer-congestion-algorithm
23095 The TCP congestion-control algorithm to use for peer connections,
23096 specified using a string recognized by the operating system in calls to
23097 @code{setsockopt} (or set to @code{disabled}, in which case the
23098 operating-system default is used).
23100 Note that on GNU/Linux systems, the kernel must be configured to allow
23101 processes to use a congestion-control algorithm not in the default set;
23102 otherwise, it will deny these requests with ``Operation not permitted''.
23103 To see which algorithms are available on your system and which are
23104 currently permitted for use, look at the contents of the files
23105 @file{tcp_available_congestion_control} and
23106 @file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
23109 As an example, to have Transmission Daemon use
23110 @uref{http://www-ece.rice.edu/networks/TCP-LP/,the TCP Low Priority
23111 congestion-control algorithm}, you'll need to modify your kernel
23112 configuration to build in support for the algorithm, then update your
23113 operating-system configuration to allow its use by adding a
23114 @code{sysctl-service-type} service (or updating the existing one's
23115 configuration) with lines like the following:
23118 (service sysctl-service-type
23119 (sysctl-configuration
23121 ("net.ipv4.tcp_allowed_congestion_control" .
23122 "reno cubic lp"))))
23125 The Transmission Daemon configuration can then be updated with
23128 (peer-congestion-algorithm "lp")
23131 and the system reconfigured to have the changes take effect.
23133 Defaults to @samp{disabled}.
23137 @deftypevr {@code{transmission-daemon-configuration} parameter} tcp-type-of-service peer-socket-tos
23138 The type of service to request in outgoing @acronym{TCP} packets, one of
23139 @code{default}, @code{low-cost}, @code{throughput}, @code{low-delay} and
23140 @code{reliability}.
23142 Defaults to @samp{default}.
23146 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-global
23147 The global limit on the number of connected peers.
23149 Defaults to @samp{200}.
23153 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-per-torrent
23154 The per-torrent limit on the number of connected peers.
23156 Defaults to @samp{50}.
23160 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer upload-slots-per-torrent
23161 The maximum number of peers to which the daemon will upload data
23162 simultaneously for each torrent.
23164 Defaults to @samp{14}.
23168 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-id-ttl-hours
23169 The maximum lifespan, in hours, of the peer ID associated with each
23170 public torrent before it is regenerated.
23172 Defaults to @samp{6}.
23176 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean blocklist-enabled?
23177 When @code{#t}, the daemon will ignore peers mentioned in the blocklist
23178 it has most recently downloaded from @code{blocklist-url}.
23180 Defaults to @samp{#f}.
23184 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string blocklist-url
23185 The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
23186 @file{.dat} format) to be periodically downloaded and applied when
23187 @code{blocklist-enabled?} is @code{#t}.
23189 Defaults to @samp{disabled}.
23193 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean download-queue-enabled?
23194 If @code{#t}, the daemon will be limited to downloading at most
23195 @code{download-queue-size} non-stalled torrents simultaneously.
23197 Defaults to @samp{#t}.
23201 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer download-queue-size
23202 The size of the daemon's download queue, which limits the number of
23203 non-stalled torrents it will download at any one time when
23204 @code{download-queue-enabled?} is @code{#t}.
23206 Defaults to @samp{5}.
23210 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean seed-queue-enabled?
23211 If @code{#t}, the daemon will be limited to seeding at most
23212 @code{seed-queue-size} non-stalled torrents simultaneously.
23214 Defaults to @samp{#f}.
23218 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer seed-queue-size
23219 The size of the daemon's seed queue, which limits the number of
23220 non-stalled torrents it will seed at any one time when
23221 @code{seed-queue-enabled?} is @code{#t}.
23223 Defaults to @samp{10}.
23227 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean queue-stalled-enabled?
23228 When @code{#t}, the daemon will consider torrents for which it has not
23229 shared data in the past @code{queue-stalled-minutes} minutes to be
23230 stalled and not count them against its @code{download-queue-size} and
23231 @code{seed-queue-size} limits.
23233 Defaults to @samp{#t}.
23237 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer queue-stalled-minutes
23238 The maximum period, in minutes, a torrent may be idle before it is
23239 considered to be stalled, when @code{queue-stalled-enabled?} is
23242 Defaults to @samp{30}.
23246 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean ratio-limit-enabled?
23247 When @code{#t}, a torrent being seeded will automatically be paused once
23248 it reaches the ratio specified by @code{ratio-limit}.
23250 Defaults to @samp{#f}.
23254 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-rational ratio-limit
23255 The ratio at which a torrent being seeded will be paused, when
23256 @code{ratio-limit-enabled?} is @code{#t}.
23258 Defaults to @samp{2.0}.
23262 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean idle-seeding-limit-enabled?
23263 When @code{#t}, a torrent being seeded will automatically be paused once
23264 it has been idle for @code{idle-seeding-limit} minutes.
23266 Defaults to @samp{#f}.
23270 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer idle-seeding-limit
23271 The maximum period, in minutes, a torrent being seeded may be idle
23272 before it is paused, when @code{idle-seeding-limit-enabled?} is
23275 Defaults to @samp{30}.
23279 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean dht-enabled?
23280 Enable @uref{http://bittorrent.org/beps/bep_0005.html,the distributed
23281 hash table (@acronym{DHT}) protocol}, which supports the use of
23282 trackerless torrents.
23284 Defaults to @samp{#t}.
23288 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean lpd-enabled?
23289 Enable @uref{https://en.wikipedia.org/wiki/Local_Peer_Discovery,local
23290 peer discovery} (@acronym{LPD}), which allows the discovery of peers on
23291 the local network and may reduce the amount of data sent over the public
23294 Defaults to @samp{#f}.
23298 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean pex-enabled?
23299 Enable @uref{https://en.wikipedia.org/wiki/Peer_exchange,peer exchange}
23300 (@acronym{PEX}), which reduces the daemon's reliance on external
23301 trackers and may improve its performance.
23303 Defaults to @samp{#t}.
23307 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean utp-enabled?
23308 Enable @uref{http://bittorrent.org/beps/bep_0029.html,the micro
23309 transport protocol} (@acronym{uTP}), which aims to reduce the impact of
23310 BitTorrent traffic on other users of the local network while maintaining
23311 full utilization of the available bandwidth.
23313 Defaults to @samp{#t}.
23317 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-enabled?
23318 If @code{#t}, enable the remote procedure call (@acronym{RPC})
23319 interface, which allows remote control of the daemon via its Web
23320 interface, the @command{transmission-remote} command-line client, and
23323 Defaults to @samp{#t}.
23327 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-bind-address
23328 The IP address at which to listen for @acronym{RPC} connections, or
23329 ``0.0.0.0'' to listen at all available IP addresses.
23331 Defaults to @samp{"0.0.0.0"}.
23335 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number rpc-port
23336 The port on which to listen for @acronym{RPC} connections.
23338 Defaults to @samp{9091}.
23342 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-url
23343 The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.
23345 Defaults to @samp{"/transmission/"}.
23349 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-authentication-required?
23350 When @code{#t}, clients must authenticate (see @code{rpc-username} and
23351 @code{rpc-password}) when using the @acronym{RPC} interface. Note this
23352 has the side effect of disabling host-name whitelisting (see
23353 @code{rpc-host-whitelist-enabled?}.
23355 Defaults to @samp{#f}.
23359 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string rpc-username
23360 The username required by clients to access the @acronym{RPC} interface
23361 when @code{rpc-authentication-required?} is @code{#t}.
23363 Defaults to @samp{disabled}.
23367 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-transmission-password-hash rpc-password
23368 The password required by clients to access the @acronym{RPC} interface
23369 when @code{rpc-authentication-required?} is @code{#t}. This must be
23370 specified using a password hash in the format recognized by Transmission
23371 clients, either copied from an existing @file{settings.json} file or
23372 generated using the @code{transmission-password-hash} procedure.
23374 Defaults to @samp{disabled}.
23378 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-whitelist-enabled?
23379 When @code{#t}, @acronym{RPC} requests will be accepted only when they
23380 originate from an address specified in @code{rpc-whitelist}.
23382 Defaults to @samp{#t}.
23386 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-whitelist
23387 The list of IP and IPv6 addresses from which @acronym{RPC} requests will
23388 be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards
23389 may be specified using @samp{*}.
23391 Defaults to @samp{("127.0.0.1" "::1")}.
23395 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-host-whitelist-enabled?
23396 When @code{#t}, @acronym{RPC} requests will be accepted only when they
23397 are addressed to a host named in @code{rpc-host-whitelist}. Note that
23398 requests to ``localhost'' or ``localhost.'', or to a numeric address,
23399 are always accepted regardless of these settings.
23401 Note also this functionality is disabled when
23402 @code{rpc-authentication-required?} is @code{#t}.
23404 Defaults to @samp{#t}.
23408 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-host-whitelist
23409 The list of host names recognized by the @acronym{RPC} server when
23410 @code{rpc-host-whitelist-enabled?} is @code{#t}.
23412 Defaults to @samp{()}.
23416 @deftypevr {@code{transmission-daemon-configuration} parameter} message-level message-level
23417 The minimum severity level of messages to be logged (to
23418 @file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
23419 logging), @code{error}, @code{info} and @code{debug}.
23421 Defaults to @samp{info}.
23425 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean start-added-torrents?
23426 When @code{#t}, torrents are started as soon as they are added;
23427 otherwise, they are added in ``paused'' state.
23429 Defaults to @samp{#t}.
23433 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean script-torrent-done-enabled?
23434 When @code{#t}, the script specified by
23435 @code{script-torrent-done-filename} will be invoked each time a torrent
23438 Defaults to @samp{#f}.
23442 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-file-object script-torrent-done-filename
23443 A file name or file-like object specifying a script to run each time a
23444 torrent completes, when @code{script-torrent-done-enabled?} is
23447 Defaults to @samp{disabled}.
23451 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean scrape-paused-torrents-enabled?
23452 When @code{#t}, the daemon will scrape trackers for a torrent even when
23453 the torrent is paused.
23455 Defaults to @samp{#t}.
23459 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer cache-size-mb
23460 The amount of memory, in megabytes, to allocate for the daemon's
23461 in-memory cache. A larger value may increase performance by reducing
23462 the frequency of disk I/O.
23464 Defaults to @samp{4}.
23468 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean prefetch-enabled?
23469 When @code{#t}, the daemon will try to improve I/O performance by
23470 hinting to the operating system which data is likely to be read next
23471 from disk to satisfy requests from peers.
23473 Defaults to @samp{#t}.
23478 @c %end of fragment
23482 @node Monitoring Services
23483 @subsection Monitoring Services
23485 @subsubheading Tailon Service
23487 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
23488 viewing and searching log files.
23490 The following example will configure the service with default values.
23491 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
23494 (service tailon-service-type)
23497 The following example customises more of the Tailon configuration,
23498 adding @command{sed} to the list of allowed commands.
23501 (service tailon-service-type
23502 (tailon-configuration
23504 (tailon-configuration-file
23505 (allowed-commands '("tail" "grep" "awk" "sed"))))))
23509 @deftp {Data Type} tailon-configuration
23510 Data type representing the configuration of Tailon.
23511 This type has the following parameters:
23514 @item @code{config-file} (default: @code{(tailon-configuration-file)})
23515 The configuration file to use for Tailon. This can be set to a
23516 @dfn{tailon-configuration-file} record value, or any gexp
23517 (@pxref{G-Expressions}).
23519 For example, to instead use a local file, the @code{local-file} function
23523 (service tailon-service-type
23524 (tailon-configuration
23525 (config-file (local-file "./my-tailon.conf"))))
23528 @item @code{package} (default: @code{tailon})
23529 The tailon package to use.
23534 @deftp {Data Type} tailon-configuration-file
23535 Data type representing the configuration options for Tailon.
23536 This type has the following parameters:
23539 @item @code{files} (default: @code{(list "/var/log")})
23540 List of files to display. The list can include strings for a single file
23541 or directory, or a list, where the first item is the name of a
23542 subsection, and the remaining items are the files or directories in that
23545 @item @code{bind} (default: @code{"localhost:8080"})
23546 Address and port to which Tailon should bind on.
23548 @item @code{relative-root} (default: @code{#f})
23549 URL path to use for Tailon, set to @code{#f} to not use a path.
23551 @item @code{allow-transfers?} (default: @code{#t})
23552 Allow downloading the log files in the web interface.
23554 @item @code{follow-names?} (default: @code{#t})
23555 Allow tailing of not-yet existent files.
23557 @item @code{tail-lines} (default: @code{200})
23558 Number of lines to read initially from each file.
23560 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
23561 Commands to allow running. By default, @code{sed} is disabled.
23563 @item @code{debug?} (default: @code{#f})
23564 Set @code{debug?} to @code{#t} to show debug messages.
23566 @item @code{wrap-lines} (default: @code{#t})
23567 Initial line wrapping state in the web interface. Set to @code{#t} to
23568 initially wrap lines (the default), or to @code{#f} to initially not
23571 @item @code{http-auth} (default: @code{#f})
23572 HTTP authentication type to use. Set to @code{#f} to disable
23573 authentication (the default). Supported values are @code{"digest"} or
23576 @item @code{users} (default: @code{#f})
23577 If HTTP authentication is enabled (see @code{http-auth}), access will be
23578 restricted to the credentials provided here. To configure users, use a
23579 list of pairs, where the first element of the pair is the username, and
23580 the 2nd element of the pair is the password.
23583 (tailon-configuration-file
23584 (http-auth "basic")
23585 (users '(("user1" . "password1")
23586 ("user2" . "password2"))))
23593 @subsubheading Darkstat Service
23595 Darkstat is a packet sniffer that captures network traffic, calculates
23596 statistics about usage, and serves reports over HTTP.
23598 @defvar {Scheme Variable} darkstat-service-type
23599 This is the service type for the
23600 @uref{https://unix4lyfe.org/darkstat/, darkstat}
23601 service, its value must be a @code{darkstat-configuration} record as in
23605 (service darkstat-service-type
23606 (darkstat-configuration
23607 (interface "eno1")))
23611 @deftp {Data Type} darkstat-configuration
23612 Data type representing the configuration of @command{darkstat}.
23615 @item @code{package} (default: @code{darkstat})
23616 The darkstat package to use.
23618 @item @code{interface}
23619 Capture traffic on the specified network interface.
23621 @item @code{port} (default: @code{"667"})
23622 Bind the web interface to the specified port.
23624 @item @code{bind-address} (default: @code{"127.0.0.1"})
23625 Bind the web interface to the specified address.
23627 @item @code{base} (default: @code{"/"})
23628 Specify the path of the base URL@. This can be useful if
23629 @command{darkstat} is accessed via a reverse proxy.
23634 @subsubheading Prometheus Node Exporter Service
23636 @cindex prometheus-node-exporter
23637 The Prometheus ``node exporter'' makes hardware and operating system statistics
23638 provided by the Linux kernel available for the Prometheus monitoring system.
23639 This service should be deployed on all physical nodes and virtual machines,
23640 where monitoring these statistics is desirable.
23642 @defvar {Scheme variable} prometheus-node-exporter-service-type
23643 This is the service type for the
23644 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
23645 service, its value must be a @code{prometheus-node-exporter-configuration}.
23648 (service prometheus-node-exporter-service-type)
23652 @deftp {Data Type} prometheus-node-exporter-configuration
23653 Data type representing the configuration of @command{node_exporter}.
23656 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
23657 The prometheus-node-exporter package to use.
23659 @item @code{web-listen-address} (default: @code{":9100"})
23660 Bind the web interface to the specified address.
23662 @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
23663 This directory can be used to export metrics specific to this machine.
23664 Files containing metrics in the text format, with the filename ending in
23665 @code{.prom} should be placed in this directory.
23667 @item @code{extra-options} (default: @code{'()})
23668 Extra options to pass to the Prometheus node exporter.
23673 @subsubheading Zabbix server
23674 @cindex zabbix zabbix-server
23675 Zabbix provides monitoring metrics, among others network utilization, CPU load
23676 and disk space consumption:
23679 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
23680 @item Auto-discovery of servers and network devices and interfaces.
23681 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
23682 @item Distributed monitoring with centralized web administration.
23683 @item Native high performance agents.
23684 @item SLA, and ITIL KPI metrics on reporting.
23685 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
23686 @item Remote command execution through Zabbix proxies.
23689 @c %start of fragment
23691 Available @code{zabbix-server-configuration} fields are:
23693 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
23694 The zabbix-server package.
23698 @deftypevr {@code{zabbix-server-configuration} parameter} string user
23699 User who will run the Zabbix server.
23701 Defaults to @samp{"zabbix"}.
23705 @deftypevr {@code{zabbix-server-configuration} parameter} group group
23706 Group who will run the Zabbix server.
23708 Defaults to @samp{"zabbix"}.
23712 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
23713 Database host name.
23715 Defaults to @samp{"127.0.0.1"}.
23719 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
23722 Defaults to @samp{"zabbix"}.
23726 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
23729 Defaults to @samp{"zabbix"}.
23733 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
23734 Database password. Please, use @code{include-files} with
23735 @code{DBPassword=SECRET} inside a specified file instead.
23737 Defaults to @samp{""}.
23741 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
23744 Defaults to @samp{5432}.
23748 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
23749 Specifies where log messages are written to:
23753 @code{system} - syslog.
23756 @code{file} - file specified with @code{log-file} parameter.
23759 @code{console} - standard output.
23763 Defaults to @samp{""}.
23767 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
23768 Log file name for @code{log-type} @code{file} parameter.
23770 Defaults to @samp{"/var/log/zabbix/server.log"}.
23774 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
23777 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
23781 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
23782 The location of certificate authority (CA) files for SSL server
23783 certificate verification.
23785 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
23789 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
23790 Location of SSL client certificates.
23792 Defaults to @samp{"/etc/ssl/certs"}.
23796 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
23797 Extra options will be appended to Zabbix server configuration file.
23799 Defaults to @samp{""}.
23803 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
23804 You may include individual files or all files in a directory in the
23805 configuration file.
23807 Defaults to @samp{()}.
23811 @c %end of fragment
23813 @subsubheading Zabbix agent
23814 @cindex zabbix zabbix-agent
23816 Zabbix agent gathers information for Zabbix server.
23818 @c %start of fragment
23820 Available @code{zabbix-agent-configuration} fields are:
23822 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
23823 The zabbix-agent package.
23827 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
23828 User who will run the Zabbix agent.
23830 Defaults to @samp{"zabbix"}.
23834 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
23835 Group who will run the Zabbix agent.
23837 Defaults to @samp{"zabbix"}.
23841 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
23842 Unique, case sensitive hostname which is required for active checks and
23843 must match hostname as configured on the server.
23845 Defaults to @samp{""}.
23849 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
23850 Specifies where log messages are written to:
23854 @code{system} - syslog.
23857 @code{file} - file specified with @code{log-file} parameter.
23860 @code{console} - standard output.
23864 Defaults to @samp{""}.
23868 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
23869 Log file name for @code{log-type} @code{file} parameter.
23871 Defaults to @samp{"/var/log/zabbix/agent.log"}.
23875 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
23878 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
23882 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
23883 List of IP addresses, optionally in CIDR notation, or hostnames of
23884 Zabbix servers and Zabbix proxies. Incoming connections will be
23885 accepted only from the hosts listed here.
23887 Defaults to @samp{("127.0.0.1")}.
23891 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
23892 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
23893 proxies for active checks. If port is not specified, default port is
23894 used. If this parameter is not specified, active checks are disabled.
23896 Defaults to @samp{("127.0.0.1")}.
23900 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
23901 Extra options will be appended to Zabbix server configuration file.
23903 Defaults to @samp{""}.
23907 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
23908 You may include individual files or all files in a directory in the
23909 configuration file.
23911 Defaults to @samp{()}.
23915 @c %end of fragment
23917 @subsubheading Zabbix front-end
23918 @cindex zabbix zabbix-front-end
23920 This service provides a WEB interface to Zabbix server.
23922 @c %start of fragment
23924 Available @code{zabbix-front-end-configuration} fields are:
23926 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
23927 NGINX configuration.
23931 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
23932 Database host name.
23934 Defaults to @samp{"localhost"}.
23938 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
23941 Defaults to @samp{5432}.
23945 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
23948 Defaults to @samp{"zabbix"}.
23952 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
23955 Defaults to @samp{"zabbix"}.
23959 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
23960 Database password. Please, use @code{db-secret-file} instead.
23962 Defaults to @samp{""}.
23966 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
23967 Secret file containing the credentials for the Zabbix front-end. The value
23968 must be a local file name, not a G-expression. You are expected to create
23969 this file manually. Its contents will be copied into @file{zabbix.conf.php}
23970 as the value of @code{$DB['PASSWORD']}.
23972 Defaults to @samp{""}.
23976 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
23977 Zabbix server hostname.
23979 Defaults to @samp{"localhost"}.
23983 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
23984 Zabbix server port.
23986 Defaults to @samp{10051}.
23991 @c %end of fragment
23993 @node Kerberos Services
23994 @subsection Kerberos Services
23997 The @code{(gnu services kerberos)} module provides services relating to
23998 the authentication protocol @dfn{Kerberos}.
24000 @subsubheading Krb5 Service
24002 Programs using a Kerberos client library normally
24003 expect a configuration file in @file{/etc/krb5.conf}.
24004 This service generates such a file from a definition provided in the
24005 operating system declaration.
24006 It does not cause any daemon to be started.
24008 No ``keytab'' files are provided by this service---you must explicitly create them.
24009 This service is known to work with the MIT client library, @code{mit-krb5}.
24010 Other implementations have not been tested.
24012 @defvr {Scheme Variable} krb5-service-type
24013 A service type for Kerberos 5 clients.
24017 Here is an example of its use:
24019 (service krb5-service-type
24020 (krb5-configuration
24021 (default-realm "EXAMPLE.COM")
24022 (allow-weak-crypto? #t)
24025 (name "EXAMPLE.COM")
24026 (admin-server "groucho.example.com")
24027 (kdc "karl.example.com"))
24030 (admin-server "kerb-admin.argrx.edu")
24031 (kdc "keys.argrx.edu"))))))
24035 This example provides a Kerberos@tie{}5 client configuration which:
24037 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
24038 of which have distinct administration servers and key distribution centers;
24039 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
24040 specified by clients;
24041 @item Accepts services which only support encryption types known to be weak.
24044 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
24045 Only the most commonly used ones are described here.
24046 For a full list, and more detailed explanation of each, see the MIT
24047 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
24051 @deftp {Data Type} krb5-realm
24052 @cindex realm, kerberos
24055 This field is a string identifying the name of the realm.
24056 A common convention is to use the fully qualified DNS name of your organization,
24057 converted to upper case.
24059 @item @code{admin-server}
24060 This field is a string identifying the host where the administration server is
24064 This field is a string identifying the key distribution center
24069 @deftp {Data Type} krb5-configuration
24072 @item @code{allow-weak-crypto?} (default: @code{#f})
24073 If this flag is @code{#t} then services which only offer encryption algorithms
24074 known to be weak will be accepted.
24076 @item @code{default-realm} (default: @code{#f})
24077 This field should be a string identifying the default Kerberos
24078 realm for the client.
24079 You should set this field to the name of your Kerberos realm.
24080 If this value is @code{#f}
24081 then a realm must be specified with every Kerberos principal when invoking programs
24082 such as @command{kinit}.
24084 @item @code{realms}
24085 This should be a non-empty list of @code{krb5-realm} objects, which clients may
24087 Normally, one of them will have a @code{name} field matching the @code{default-realm}
24093 @subsubheading PAM krb5 Service
24096 The @code{pam-krb5} service allows for login authentication and password
24097 management via Kerberos.
24098 You will need this service if you want PAM enabled applications to authenticate
24099 users using Kerberos.
24101 @defvr {Scheme Variable} pam-krb5-service-type
24102 A service type for the Kerberos 5 PAM module.
24105 @deftp {Data Type} pam-krb5-configuration
24106 Data type representing the configuration of the Kerberos 5 PAM module.
24107 This type has the following parameters:
24109 @item @code{pam-krb5} (default: @code{pam-krb5})
24110 The pam-krb5 package to use.
24112 @item @code{minimum-uid} (default: @code{1000})
24113 The smallest user ID for which Kerberos authentications should be attempted.
24114 Local accounts with lower values will silently fail to authenticate.
24119 @node LDAP Services
24120 @subsection LDAP Services
24122 @cindex nslcd, LDAP service
24124 The @code{(gnu services authentication)} module provides the
24125 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
24126 server. In addition to configuring the service itself, you may want to add
24127 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
24128 Switch} for detailed information.
24130 Here is a simple operating system declaration with a default configuration of
24131 the @code{nslcd-service-type} and a Name Service Switch configuration that
24132 consults the @code{ldap} name service last:
24135 (use-service-modules authentication)
24136 (use-modules (gnu system nss))
24142 (service nslcd-service-type)
24143 (service dhcp-client-service-type)
24145 (name-service-switch
24146 (let ((services (list (name-service (name "db"))
24147 (name-service (name "files"))
24148 (name-service (name "ldap")))))
24149 (name-service-switch
24150 (inherit %mdns-host-lookup-nss)
24151 (password services)
24154 (netgroup services)
24155 (gshadow services)))))
24158 @c %start of generated documentation for nslcd-configuration
24160 Available @code{nslcd-configuration} fields are:
24162 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
24163 The @code{nss-pam-ldapd} package to use.
24167 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
24168 The number of threads to start that can handle requests and perform LDAP
24169 queries. Each thread opens a separate connection to the LDAP server.
24170 The default is to start 5 threads.
24172 Defaults to @samp{disabled}.
24176 @deftypevr {@code{nslcd-configuration} parameter} string uid
24177 This specifies the user id with which the daemon should be run.
24179 Defaults to @samp{"nslcd"}.
24183 @deftypevr {@code{nslcd-configuration} parameter} string gid
24184 This specifies the group id with which the daemon should be run.
24186 Defaults to @samp{"nslcd"}.
24190 @deftypevr {@code{nslcd-configuration} parameter} log-option log
24191 This option controls the way logging is done via a list containing
24192 SCHEME and LEVEL@. The SCHEME argument may either be the symbols
24193 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
24194 argument is optional and specifies the log level. The log level may be
24195 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
24196 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
24197 specified log level or higher are logged.
24199 Defaults to @samp{("/var/log/nslcd" info)}.
24203 @deftypevr {@code{nslcd-configuration} parameter} list uri
24204 The list of LDAP server URIs. Normally, only the first server will be
24205 used with the following servers as fall-back.
24207 Defaults to @samp{("ldap://localhost:389/")}.
24211 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
24212 The version of the LDAP protocol to use. The default is to use the
24213 maximum version supported by the LDAP library.
24215 Defaults to @samp{disabled}.
24219 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
24220 Specifies the distinguished name with which to bind to the directory
24221 server for lookups. The default is to bind anonymously.
24223 Defaults to @samp{disabled}.
24227 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
24228 Specifies the credentials with which to bind. This option is only
24229 applicable when used with binddn.
24231 Defaults to @samp{disabled}.
24235 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
24236 Specifies the distinguished name to use when the root user tries to
24237 modify a user's password using the PAM module.
24239 Defaults to @samp{disabled}.
24243 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
24244 Specifies the credentials with which to bind if the root user tries to
24245 change a user's password. This option is only applicable when used with
24248 Defaults to @samp{disabled}.
24252 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
24253 Specifies the SASL mechanism to be used when performing SASL
24256 Defaults to @samp{disabled}.
24260 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
24261 Specifies the SASL realm to be used when performing SASL authentication.
24263 Defaults to @samp{disabled}.
24267 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
24268 Specifies the authentication identity to be used when performing SASL
24271 Defaults to @samp{disabled}.
24275 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
24276 Specifies the authorization identity to be used when performing SASL
24279 Defaults to @samp{disabled}.
24283 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
24284 Determines whether the LDAP server host name should be canonicalised. If
24285 this is enabled the LDAP library will do a reverse host name lookup. By
24286 default, it is left up to the LDAP library whether this check is
24289 Defaults to @samp{disabled}.
24293 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
24294 Set the name for the GSS-API Kerberos credentials cache.
24296 Defaults to @samp{disabled}.
24300 @deftypevr {@code{nslcd-configuration} parameter} string base
24301 The directory search base.
24303 Defaults to @samp{"dc=example,dc=com"}.
24307 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
24308 Specifies the search scope (subtree, onelevel, base or children). The
24309 default scope is subtree; base scope is almost never useful for name
24310 service lookups; children scope is not supported on all servers.
24312 Defaults to @samp{(subtree)}.
24316 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
24317 Specifies the policy for dereferencing aliases. The default policy is
24318 to never dereference aliases.
24320 Defaults to @samp{disabled}.
24324 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
24325 Specifies whether automatic referral chasing should be enabled. The
24326 default behaviour is to chase referrals.
24328 Defaults to @samp{disabled}.
24332 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
24333 This option allows for custom attributes to be looked up instead of the
24334 default RFC 2307 attributes. It is a list of maps, each consisting of
24335 the name of a map, the RFC 2307 attribute to match and the query
24336 expression for the attribute as it is available in the directory.
24338 Defaults to @samp{()}.
24342 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
24343 A list of filters consisting of the name of a map to which the filter
24344 applies and an LDAP search filter expression.
24346 Defaults to @samp{()}.
24350 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
24351 Specifies the time limit in seconds to use when connecting to the
24352 directory server. The default value is 10 seconds.
24354 Defaults to @samp{disabled}.
24358 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
24359 Specifies the time limit (in seconds) to wait for a response from the
24360 LDAP server. A value of zero, which is the default, is to wait
24361 indefinitely for searches to be completed.
24363 Defaults to @samp{disabled}.
24367 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
24368 Specifies the period if inactivity (in seconds) after which the con‐
24369 nection to the LDAP server will be closed. The default is not to time
24372 Defaults to @samp{disabled}.
24376 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
24377 Specifies the number of seconds to sleep when connecting to all LDAP
24378 servers fails. By default one second is waited between the first
24379 failure and the first retry.
24381 Defaults to @samp{disabled}.
24385 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
24386 Specifies the time after which the LDAP server is considered to be
24387 permanently unavailable. Once this time is reached retries will be done
24388 only once per this time period. The default value is 10 seconds.
24390 Defaults to @samp{disabled}.
24394 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
24395 Specifies whether to use SSL/TLS or not (the default is not to). If
24396 'start-tls is specified then StartTLS is used rather than raw LDAP over
24399 Defaults to @samp{disabled}.
24403 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
24404 Specifies what checks to perform on a server-supplied certificate. The
24405 meaning of the values is described in the ldap.conf(5) manual page.
24407 Defaults to @samp{disabled}.
24411 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
24412 Specifies the directory containing X.509 certificates for peer authen‐
24413 tication. This parameter is ignored when using GnuTLS.
24415 Defaults to @samp{disabled}.
24419 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
24420 Specifies the path to the X.509 certificate for peer authentication.
24422 Defaults to @samp{disabled}.
24426 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
24427 Specifies the path to an entropy source. This parameter is ignored when
24430 Defaults to @samp{disabled}.
24434 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
24435 Specifies the ciphers to use for TLS as a string.
24437 Defaults to @samp{disabled}.
24441 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
24442 Specifies the path to the file containing the local certificate for
24443 client TLS authentication.
24445 Defaults to @samp{disabled}.
24449 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
24450 Specifies the path to the file containing the private key for client TLS
24453 Defaults to @samp{disabled}.
24457 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
24458 Set this to a number greater than 0 to request paged results from the
24459 LDAP server in accordance with RFC2696. The default (0) is to not
24460 request paged results.
24462 Defaults to @samp{disabled}.
24466 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
24467 This option prevents group membership lookups through LDAP for the
24468 specified users. Alternatively, the value 'all-local may be used. With
24469 that value nslcd builds a full list of non-LDAP users on startup.
24471 Defaults to @samp{disabled}.
24475 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
24476 This option ensures that LDAP users with a numeric user id lower than
24477 the specified value are ignored.
24479 Defaults to @samp{disabled}.
24483 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
24484 This option specifies an offset that is added to all LDAP numeric user
24485 ids. This can be used to avoid user id collisions with local users.
24487 Defaults to @samp{disabled}.
24491 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
24492 This option specifies an offset that is added to all LDAP numeric group
24493 ids. This can be used to avoid user id collisions with local groups.
24495 Defaults to @samp{disabled}.
24499 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
24500 If this option is set, the member attribute of a group may point to
24501 another group. Members of nested groups are also returned in the higher
24502 level group and parent groups are returned when finding groups for a
24503 specific user. The default is not to perform extra searches for nested
24506 Defaults to @samp{disabled}.
24510 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
24511 If this option is set, the group member list is not retrieved when
24512 looking up groups. Lookups for finding which groups a user belongs to
24513 will remain functional so the user will likely still get the correct
24514 groups assigned on login.
24516 Defaults to @samp{disabled}.
24520 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
24521 If this option is set, functions which cause all user/group entries to
24522 be loaded from the directory will not succeed in doing so. This can
24523 dramatically reduce LDAP server load in situations where there are a
24524 great number of users and/or groups. This option is not recommended for
24525 most configurations.
24527 Defaults to @samp{disabled}.
24531 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
24532 This option can be used to specify how user and group names are verified
24533 within the system. This pattern is used to check all user and group
24534 names that are requested and returned from LDAP.
24536 Defaults to @samp{disabled}.
24540 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
24541 This specifies whether or not to perform searches using case-insensitive
24542 matching. Enabling this could open up the system to authorization
24543 bypass vulnerabilities and introduce nscd cache poisoning
24544 vulnerabilities which allow denial of service.
24546 Defaults to @samp{disabled}.
24550 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
24551 This option specifies whether password policy controls are requested and
24552 handled from the LDAP server when performing user authentication.
24554 Defaults to @samp{disabled}.
24558 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
24559 By default nslcd performs an LDAP search with the user's credentials
24560 after BIND (authentication) to ensure that the BIND operation was
24561 successful. The default search is a simple check to see if the user's
24562 DN exists. A search filter can be specified that will be used instead.
24563 It should return at least one entry.
24565 Defaults to @samp{disabled}.
24569 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
24570 This option allows flexible fine tuning of the authorisation check that
24571 should be performed. The search filter specified is executed and if any
24572 entries match, access is granted, otherwise access is denied.
24574 Defaults to @samp{disabled}.
24578 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
24579 If this option is set password modification using pam_ldap will be
24580 denied and the specified message will be presented to the user instead.
24581 The message can be used to direct the user to an alternative means of
24582 changing their password.
24584 Defaults to @samp{disabled}.
24588 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
24589 List of pam service names for which LDAP authentication should suffice.
24591 Defaults to @samp{()}.
24595 @c %end of generated documentation for nslcd-configuration
24599 @subsection Web Services
24604 The @code{(gnu services web)} module provides the Apache HTTP Server,
24605 the nginx web server, and also a fastcgi wrapper daemon.
24607 @subsubheading Apache HTTP Server
24609 @deffn {Scheme Variable} httpd-service-type
24610 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
24611 (@dfn{httpd}). The value for this service type is a
24612 @code{httpd-configuration} record.
24614 A simple example configuration is given below.
24617 (service httpd-service-type
24618 (httpd-configuration
24621 (server-name "www.example.com")
24622 (document-root "/srv/http/www.example.com")))))
24625 Other services can also extend the @code{httpd-service-type} to add to
24629 (simple-service 'www.example.com-server httpd-service-type
24633 (list (string-join '("ServerName www.example.com"
24634 "DocumentRoot /srv/http/www.example.com")
24639 The details for the @code{httpd-configuration}, @code{httpd-module},
24640 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
24643 @deffn {Data Type} httpd-configuration
24644 This data type represents the configuration for the httpd service.
24647 @item @code{package} (default: @code{httpd})
24648 The httpd package to use.
24650 @item @code{pid-file} (default: @code{"/var/run/httpd"})
24651 The pid file used by the shepherd-service.
24653 @item @code{config} (default: @code{(httpd-config-file)})
24654 The configuration file to use with the httpd service. The default value
24655 is a @code{httpd-config-file} record, but this can also be a different
24656 G-expression that generates a file, for example a @code{plain-file}. A
24657 file outside of the store can also be specified through a string.
24662 @deffn {Data Type} httpd-module
24663 This data type represents a module for the httpd service.
24667 The name of the module.
24670 The file for the module. This can be relative to the httpd package being
24671 used, the absolute location of a file, or a G-expression for a file
24672 within the store, for example @code{(file-append mod-wsgi
24673 "/modules/mod_wsgi.so")}.
24678 @defvr {Scheme Variable} %default-httpd-modules
24679 A default list of @code{httpd-module} objects.
24682 @deffn {Data Type} httpd-config-file
24683 This data type represents a configuration file for the httpd service.
24686 @item @code{modules} (default: @code{%default-httpd-modules})
24687 The modules to load. Additional modules can be added here, or loaded by
24688 additional configuration.
24690 For example, in order to handle requests for PHP files, you can use Apache’s
24691 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
24694 (service httpd-service-type
24695 (httpd-configuration
24700 (name "proxy_module")
24701 (file "modules/mod_proxy.so"))
24703 (name "proxy_fcgi_module")
24704 (file "modules/mod_proxy_fcgi.so"))
24705 %default-httpd-modules))
24706 (extra-config (list "\
24707 <FilesMatch \\.php$>
24708 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
24709 </FilesMatch>"))))))
24710 (service php-fpm-service-type
24711 (php-fpm-configuration
24712 (socket "/var/run/php-fpm.sock")
24713 (socket-group "httpd")))
24716 @item @code{server-root} (default: @code{httpd})
24717 The @code{ServerRoot} in the configuration file, defaults to the httpd
24718 package. Directives including @code{Include} and @code{LoadModule} are
24719 taken as relative to the server root.
24721 @item @code{server-name} (default: @code{#f})
24722 The @code{ServerName} in the configuration file, used to specify the
24723 request scheme, hostname and port that the server uses to identify
24726 This doesn't need to be set in the server config, and can be specified
24727 in virtual hosts. The default is @code{#f} to not specify a
24730 @item @code{document-root} (default: @code{"/srv/http"})
24731 The @code{DocumentRoot} from which files will be served.
24733 @item @code{listen} (default: @code{'("80")})
24734 The list of values for the @code{Listen} directives in the config
24735 file. The value should be a list of strings, when each string can
24736 specify the port number to listen on, and optionally the IP address and
24739 @item @code{pid-file} (default: @code{"/var/run/httpd"})
24740 The @code{PidFile} to use. This should match the @code{pid-file} set in
24741 the @code{httpd-configuration} so that the Shepherd service is
24742 configured correctly.
24744 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
24745 The @code{ErrorLog} to which the server will log errors.
24747 @item @code{user} (default: @code{"httpd"})
24748 The @code{User} which the server will answer requests as.
24750 @item @code{group} (default: @code{"httpd"})
24751 The @code{Group} which the server will answer requests as.
24753 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
24754 A flat list of strings and G-expressions which will be added to the end
24755 of the configuration file.
24757 Any values which the service is extended with will be appended to this
24763 @deffn {Data Type} httpd-virtualhost
24764 This data type represents a virtualhost configuration block for the httpd service.
24766 These should be added to the extra-config for the httpd-service.
24769 (simple-service 'www.example.com-server httpd-service-type
24773 (list (string-join '("ServerName www.example.com"
24774 "DocumentRoot /srv/http/www.example.com")
24779 @item @code{addresses-and-ports}
24780 The addresses and ports for the @code{VirtualHost} directive.
24782 @item @code{contents}
24783 The contents of the @code{VirtualHost} directive, this should be a list
24784 of strings and G-expressions.
24789 @subsubheading NGINX
24791 @deffn {Scheme Variable} nginx-service-type
24792 Service type for the @uref{https://nginx.org/,NGinx} web server. The
24793 value for this service type is a @code{<nginx-configuration>} record.
24795 A simple example configuration is given below.
24798 (service nginx-service-type
24799 (nginx-configuration
24801 (list (nginx-server-configuration
24802 (server-name '("www.example.com"))
24803 (root "/srv/http/www.example.com"))))))
24806 In addition to adding server blocks to the service configuration
24807 directly, this service can be extended by other services to add server
24808 blocks, as in this example:
24811 (simple-service 'my-extra-server nginx-service-type
24812 (list (nginx-server-configuration
24813 (root "/srv/http/extra-website")
24814 (try-files (list "$uri" "$uri/index.html")))))
24818 At startup, @command{nginx} has not yet read its configuration file, so
24819 it uses a default file to log error messages. If it fails to load its
24820 configuration file, that is where error messages are logged. After the
24821 configuration file is loaded, the default error log file changes as per
24822 configuration. In our case, startup error messages can be found in
24823 @file{/var/run/nginx/logs/error.log}, and after configuration in
24824 @file{/var/log/nginx/error.log}. The second location can be changed
24825 with the @var{log-directory} configuration option.
24827 @deffn {Data Type} nginx-configuration
24828 This data type represents the configuration for NGinx. Some
24829 configuration can be done through this and the other provided record
24830 types, or alternatively, a config file can be provided.
24833 @item @code{nginx} (default: @code{nginx})
24834 The nginx package to use.
24836 @item @code{log-directory} (default: @code{"/var/log/nginx"})
24837 The directory to which NGinx will write log files.
24839 @item @code{run-directory} (default: @code{"/var/run/nginx"})
24840 The directory in which NGinx will create a pid file, and write temporary
24843 @item @code{server-blocks} (default: @code{'()})
24844 A list of @dfn{server blocks} to create in the generated configuration
24845 file, the elements should be of type
24846 @code{<nginx-server-configuration>}.
24848 The following example would setup NGinx to serve @code{www.example.com}
24849 from the @code{/srv/http/www.example.com} directory, without using
24852 (service nginx-service-type
24853 (nginx-configuration
24855 (list (nginx-server-configuration
24856 (server-name '("www.example.com"))
24857 (root "/srv/http/www.example.com"))))))
24860 @item @code{upstream-blocks} (default: @code{'()})
24861 A list of @dfn{upstream blocks} to create in the generated configuration
24862 file, the elements should be of type
24863 @code{<nginx-upstream-configuration>}.
24865 Configuring upstreams through the @code{upstream-blocks} can be useful
24866 when combined with @code{locations} in the
24867 @code{<nginx-server-configuration>} records. The following example
24868 creates a server configuration with one location configuration, that
24869 will proxy requests to a upstream configuration, which will handle
24870 requests with two servers.
24875 (nginx-configuration
24877 (list (nginx-server-configuration
24878 (server-name '("www.example.com"))
24879 (root "/srv/http/www.example.com")
24882 (nginx-location-configuration
24884 (body '("proxy_pass http://server-proxy;"))))))))
24886 (list (nginx-upstream-configuration
24887 (name "server-proxy")
24888 (servers (list "server1.example.com"
24889 "server2.example.com")))))))
24892 @item @code{file} (default: @code{#f})
24893 If a configuration @var{file} is provided, this will be used, rather than
24894 generating a configuration file from the provided @code{log-directory},
24895 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
24896 proper operation, these arguments should match what is in @var{file} to ensure
24897 that the directories are created when the service is activated.
24899 This can be useful if you have an existing configuration file, or it's
24900 not possible to do what is required through the other parts of the
24901 nginx-configuration record.
24903 @item @code{server-names-hash-bucket-size} (default: @code{#f})
24904 Bucket size for the server names hash tables, defaults to @code{#f} to
24905 use the size of the processors cache line.
24907 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
24908 Maximum bucket size for the server names hash tables.
24910 @item @code{modules} (default: @code{'()})
24911 List of nginx dynamic modules to load. This should be a list of file
24912 names of loadable modules, as in this example:
24917 (file-append nginx-accept-language-module "\
24918 /etc/nginx/modules/ngx_http_accept_language_module.so")
24919 (file-append nginx-lua-module "\
24920 /etc/nginx/modules/ngx_http_lua_module.so")))
24923 @item @code{lua-package-path} (default: @code{'()})
24924 List of nginx lua packages to load. This should be a list of package
24925 names of loadable lua modules, as in this example:
24928 (lua-package-path (list lua-resty-core
24935 @item @code{lua-package-cpath} (default: @code{'()})
24936 List of nginx lua C packages to load. This should be a list of package
24937 names of loadable lua C modules, as in this example:
24940 (lua-package-cpath (list lua-resty-signal))
24943 @item @code{global-directives} (default: @code{'((events . ()))})
24944 Association list of global directives for the top level of the nginx
24945 configuration. Values may themselves be association lists.
24949 `((worker_processes . 16)
24951 (events . ((worker_connections . 1024)))))
24954 @item @code{extra-content} (default: @code{""})
24955 Extra content for the @code{http} block. Should be string or a string
24956 valued G-expression.
24961 @deftp {Data Type} nginx-server-configuration
24962 Data type representing the configuration of an nginx server block.
24963 This type has the following parameters:
24966 @item @code{listen} (default: @code{'("80" "443 ssl")})
24967 Each @code{listen} directive sets the address and port for IP, or the
24968 path for a UNIX-domain socket on which the server will accept requests.
24969 Both address and port, or only address or only port can be specified.
24970 An address may also be a hostname, for example:
24973 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
24976 @item @code{server-name} (default: @code{(list 'default)})
24977 A list of server names this server represents. @code{'default} represents the
24978 default server for connections matching no other server.
24980 @item @code{root} (default: @code{"/srv/http"})
24981 Root of the website nginx will serve.
24983 @item @code{locations} (default: @code{'()})
24984 A list of @dfn{nginx-location-configuration} or
24985 @dfn{nginx-named-location-configuration} records to use within this
24988 @item @code{index} (default: @code{(list "index.html")})
24989 Index files to look for when clients ask for a directory. If it cannot be found,
24990 Nginx will send the list of files in the directory.
24992 @item @code{try-files} (default: @code{'()})
24993 A list of files whose existence is checked in the specified order.
24994 @code{nginx} will use the first file it finds to process the request.
24996 @item @code{ssl-certificate} (default: @code{#f})
24997 Where to find the certificate for secure connections. Set it to @code{#f} if
24998 you don't have a certificate or you don't want to use HTTPS.
25000 @item @code{ssl-certificate-key} (default: @code{#f})
25001 Where to find the private key for secure connections. Set it to @code{#f} if
25002 you don't have a key or you don't want to use HTTPS.
25004 @item @code{server-tokens?} (default: @code{#f})
25005 Whether the server should add its configuration to response.
25007 @item @code{raw-content} (default: @code{'()})
25008 A list of raw lines added to the server block.
25013 @deftp {Data Type} nginx-upstream-configuration
25014 Data type representing the configuration of an nginx @code{upstream}
25015 block. This type has the following parameters:
25019 Name for this group of servers.
25021 @item @code{servers}
25022 Specify the addresses of the servers in the group. The address can be
25023 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
25024 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
25025 prefix @samp{unix:}. For addresses using an IP address or domain name,
25026 the default port is 80, and a different port can be specified
25032 @deftp {Data Type} nginx-location-configuration
25033 Data type representing the configuration of an nginx @code{location}
25034 block. This type has the following parameters:
25038 URI which this location block matches.
25040 @anchor{nginx-location-configuration body}
25042 Body of the location block, specified as a list of strings. This can contain
25044 configuration directives. For example, to pass requests to a upstream
25045 server group defined using an @code{nginx-upstream-configuration} block,
25046 the following directive would be specified in the body @samp{(list "proxy_pass
25047 http://upstream-name;")}.
25052 @deftp {Data Type} nginx-named-location-configuration
25053 Data type representing the configuration of an nginx named location
25054 block. Named location blocks are used for request redirection, and not
25055 used for regular request processing. This type has the following
25060 Name to identify this location block.
25063 @xref{nginx-location-configuration body}, as the body for named location
25064 blocks can be used in a similar way to the
25065 @code{nginx-location-configuration body}. One restriction is that the
25066 body of a named location block cannot contain location blocks.
25071 @subsubheading Varnish Cache
25073 Varnish is a fast cache server that sits in between web applications
25074 and end users. It proxies requests from clients and caches the
25075 accessed URLs such that multiple requests for the same resource only
25076 creates one request to the back-end.
25078 @defvr {Scheme Variable} varnish-service-type
25079 Service type for the Varnish daemon.
25082 @deftp {Data Type} varnish-configuration
25083 Data type representing the @code{varnish} service configuration.
25084 This type has the following parameters:
25087 @item @code{package} (default: @code{varnish})
25088 The Varnish package to use.
25090 @item @code{name} (default: @code{"default"})
25091 A name for this Varnish instance. Varnish will create a directory in
25092 @file{/var/varnish/} with this name and keep temporary files there. If
25093 the name starts with a forward slash, it is interpreted as an absolute
25096 Pass the @code{-n} argument to other Varnish programs to connect to the
25097 named instance, e.g.@: @command{varnishncsa -n default}.
25099 @item @code{backend} (default: @code{"localhost:8080"})
25100 The backend to use. This option has no effect if @code{vcl} is set.
25102 @item @code{vcl} (default: #f)
25103 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
25104 is @code{#f}, Varnish will proxy @code{backend} using the default
25105 configuration. Otherwise this must be a file-like object with valid
25108 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
25109 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
25110 can do something along these lines:
25113 (define %gnu-mirror
25114 (plain-file "gnu.vcl"
25116 backend gnu @{ .host = \"www.gnu.org\"; @}"))
25120 (services (cons (service varnish-service-type
25121 (varnish-configuration
25123 (vcl %gnu-mirror)))
25127 The configuration of an already running Varnish instance can be inspected
25128 and changed using the @command{varnishadm} program.
25130 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
25131 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
25132 comprehensive documentation on Varnish and its configuration language.
25134 @item @code{listen} (default: @code{'("localhost:80")})
25135 List of addresses Varnish will listen on.
25137 @item @code{storage} (default: @code{'("malloc,128m")})
25138 List of storage backends that will be available in VCL.
25140 @item @code{parameters} (default: @code{'()})
25141 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
25143 @item @code{extra-options} (default: @code{'()})
25144 Additional arguments to pass to the @command{varnishd} process.
25149 @subsubheading Patchwork
25151 Patchwork is a patch tracking system. It can collect patches sent to a
25152 mailing list, and display them in a web interface.
25154 @defvr {Scheme Variable} patchwork-service-type
25155 Service type for Patchwork.
25158 The following example is an example of a minimal service for Patchwork, for
25159 the @code{patchwork.example.com} domain.
25162 (service patchwork-service-type
25163 (patchwork-configuration
25164 (domain "patchwork.example.com")
25166 (patchwork-settings-module
25167 (allowed-hosts (list domain))
25168 (default-from-email "patchwork@@patchwork.example.com")))
25169 (getmail-retriever-config
25170 (getmail-retriever-configuration
25171 (type "SimpleIMAPSSLRetriever")
25172 (server "imap.example.com")
25174 (username "patchwork")
25176 (list (file-append coreutils "/bin/cat")
25177 "/etc/getmail-patchwork-imap-password"))
25179 '((mailboxes . ("Patches"))))))))
25183 There are three records for configuring the Patchwork service. The
25184 @code{<patchwork-configuration>} relates to the configuration for Patchwork
25185 within the HTTPD service.
25187 The @code{settings-module} field within the @code{<patchwork-configuration>}
25188 record can be populated with the @code{<patchwork-settings-module>} record,
25189 which describes a settings module that is generated within the Guix store.
25191 For the @code{database-configuration} field within the
25192 @code{<patchwork-settings-module>}, the
25193 @code{<patchwork-database-configuration>} must be used.
25195 @deftp {Data Type} patchwork-configuration
25196 Data type representing the Patchwork service configuration. This type has the
25197 following parameters:
25200 @item @code{patchwork} (default: @code{patchwork})
25201 The Patchwork package to use.
25203 @item @code{domain}
25204 The domain to use for Patchwork, this is used in the HTTPD service virtual
25207 @item @code{settings-module}
25208 The settings module to use for Patchwork. As a Django application, Patchwork
25209 is configured with a Python module containing the settings. This can either be
25210 an instance of the @code{<patchwork-settings-module>} record, any other record
25211 that represents the settings in the store, or a directory outside of the
25214 @item @code{static-path} (default: @code{"/static/"})
25215 The path under which the HTTPD service should serve the static files.
25217 @item @code{getmail-retriever-config}
25218 The getmail-retriever-configuration record value to use with
25219 Patchwork. Getmail will be configured with this value, the messages will be
25220 delivered to Patchwork.
25225 @deftp {Data Type} patchwork-settings-module
25226 Data type representing a settings module for Patchwork. Some of these
25227 settings relate directly to Patchwork, but others relate to Django, the web
25228 framework used by Patchwork, or the Django Rest Framework library. This type
25229 has the following parameters:
25232 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
25233 The database connection settings used for Patchwork. See the
25234 @code{<patchwork-database-configuration>} record type for more information.
25236 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
25237 Patchwork, as a Django web application uses a secret key for cryptographically
25238 signing values. This file should contain a unique unpredictable value.
25240 If this file does not exist, it will be created and populated with a random
25241 value by the patchwork-setup shepherd service.
25243 This setting relates to Django.
25245 @item @code{allowed-hosts}
25246 A list of valid hosts for this Patchwork service. This should at least include
25247 the domain specified in the @code{<patchwork-configuration>} record.
25249 This is a Django setting.
25251 @item @code{default-from-email}
25252 The email address from which Patchwork should send email by default.
25254 This is a Patchwork setting.
25256 @item @code{static-url} (default: @code{#f})
25257 The URL to use when serving static assets. It can be part of a URL, or a full
25258 URL, but must end in a @code{/}.
25260 If the default value is used, the @code{static-path} value from the
25261 @code{<patchwork-configuration>} record will be used.
25263 This is a Django setting.
25265 @item @code{admins} (default: @code{'()})
25266 Email addresses to send the details of errors that occur. Each value should
25267 be a list containing two elements, the name and then the email address.
25269 This is a Django setting.
25271 @item @code{debug?} (default: @code{#f})
25272 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
25273 messages will be shown.
25275 This is a Django setting.
25277 @item @code{enable-rest-api?} (default: @code{#t})
25278 Whether to enable the Patchwork REST API.
25280 This is a Patchwork setting.
25282 @item @code{enable-xmlrpc?} (default: @code{#t})
25283 Whether to enable the XML RPC API.
25285 This is a Patchwork setting.
25287 @item @code{force-https-links?} (default: @code{#t})
25288 Whether to use HTTPS links on Patchwork pages.
25290 This is a Patchwork setting.
25292 @item @code{extra-settings} (default: @code{""})
25293 Extra code to place at the end of the Patchwork settings module.
25298 @deftp {Data Type} patchwork-database-configuration
25299 Data type representing the database configuration for Patchwork.
25302 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
25303 The database engine to use.
25305 @item @code{name} (default: @code{"patchwork"})
25306 The name of the database to use.
25308 @item @code{user} (default: @code{"httpd"})
25309 The user to connect to the database as.
25311 @item @code{password} (default: @code{""})
25312 The password to use when connecting to the database.
25314 @item @code{host} (default: @code{""})
25315 The host to make the database connection to.
25317 @item @code{port} (default: @code{""})
25318 The port on which to connect to the database.
25323 @subsubheading Mumi
25325 @cindex Mumi, Debbugs Web interface
25326 @cindex Debbugs, Mumi Web interface
25327 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
25328 Web interface to the Debbugs bug tracker, by default for
25329 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
25330 but it also fetches and indexes mail retrieved from Debbugs.
25332 @defvr {Scheme Variable} mumi-service-type
25333 This is the service type for Mumi.
25336 @deftp {Data Type} mumi-configuration
25337 Data type representing the Mumi service configuration. This type has the
25341 @item @code{mumi} (default: @code{mumi})
25342 The Mumi package to use.
25344 @item @code{mailer?} (default: @code{#true})
25345 Whether to enable or disable the mailer component.
25347 @item @code{mumi-configuration-sender}
25348 The email address used as the sender for comments.
25350 @item @code{mumi-configuration-smtp}
25351 A URI to configure the SMTP settings for Mailutils. This could be
25352 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
25353 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
25354 mailutils, GNU@tie{}Mailutils}.
25360 @subsubheading FastCGI
25363 FastCGI is an interface between the front-end and the back-end of a web
25364 service. It is a somewhat legacy facility; new web services should
25365 generally just talk HTTP between the front-end and the back-end.
25366 However there are a number of back-end services such as PHP or the
25367 optimized HTTP Git repository access that use FastCGI, so we have
25368 support for it in Guix.
25370 To use FastCGI, you configure the front-end web server (e.g., nginx) to
25371 dispatch some subset of its requests to the fastcgi backend, which
25372 listens on a local TCP or UNIX socket. There is an intermediary
25373 @code{fcgiwrap} program that sits between the actual backend process and
25374 the web server. The front-end indicates which backend program to run,
25375 passing that information to the @code{fcgiwrap} process.
25377 @defvr {Scheme Variable} fcgiwrap-service-type
25378 A service type for the @code{fcgiwrap} FastCGI proxy.
25381 @deftp {Data Type} fcgiwrap-configuration
25382 Data type representing the configuration of the @code{fcgiwrap} service.
25383 This type has the following parameters:
25385 @item @code{package} (default: @code{fcgiwrap})
25386 The fcgiwrap package to use.
25388 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
25389 The socket on which the @code{fcgiwrap} process should listen, as a
25390 string. Valid @var{socket} values include
25391 @code{unix:@var{/path/to/unix/socket}},
25392 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
25393 @code{tcp6:[@var{ipv6_addr}]:port}.
25395 @item @code{user} (default: @code{fcgiwrap})
25396 @itemx @code{group} (default: @code{fcgiwrap})
25397 The user and group names, as strings, under which to run the
25398 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
25399 the user asks for the specific user or group names @code{fcgiwrap} that
25400 the corresponding user and/or group is present on the system.
25402 It is possible to configure a FastCGI-backed web service to pass HTTP
25403 authentication information from the front-end to the back-end, and to
25404 allow @code{fcgiwrap} to run the back-end process as a corresponding
25405 local user. To enable this capability on the back-end, run
25406 @code{fcgiwrap} as the @code{root} user and group. Note that this
25407 capability also has to be configured on the front-end as well.
25412 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
25413 with some additional features useful for sites of any size.
25415 These features include:
25417 @item Adaptive process spawning
25418 @item Basic statistics (similar to Apache's mod_status)
25419 @item Advanced process management with graceful stop/start
25420 @item Ability to start workers with different uid/gid/chroot/environment
25421 and different php.ini (replaces safe_mode)
25422 @item Stdout & stderr logging
25423 @item Emergency restart in case of accidental opcode cache destruction
25424 @item Accelerated upload support
25425 @item Support for a "slowlog"
25426 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
25427 a special function to finish request & flush all data while continuing to do
25428 something time-consuming (video converting, stats processing, etc.)
25430 ...@: and much more.
25432 @defvr {Scheme Variable} php-fpm-service-type
25433 A Service type for @code{php-fpm}.
25436 @deftp {Data Type} php-fpm-configuration
25437 Data Type for php-fpm service configuration.
25439 @item @code{php} (default: @code{php})
25440 The php package to use.
25441 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
25442 The address on which to accept FastCGI requests. Valid syntaxes are:
25444 @item @code{"ip.add.re.ss:port"}
25445 Listen on a TCP socket to a specific address on a specific port.
25446 @item @code{"port"}
25447 Listen on a TCP socket to all addresses on a specific port.
25448 @item @code{"/path/to/unix/socket"}
25449 Listen on a unix socket.
25452 @item @code{user} (default: @code{php-fpm})
25453 User who will own the php worker processes.
25454 @item @code{group} (default: @code{php-fpm})
25455 Group of the worker processes.
25456 @item @code{socket-user} (default: @code{php-fpm})
25457 User who can speak to the php-fpm socket.
25458 @item @code{socket-group} (default: @code{nginx})
25459 Group that can speak to the php-fpm socket.
25460 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
25461 The process id of the php-fpm process is written to this file
25462 once the service has started.
25463 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
25464 Log for the php-fpm master process.
25465 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
25466 Detailed settings for the php-fpm process manager.
25469 @item @code{<php-fpm-dynamic-process-manager-configuration>}
25470 @item @code{<php-fpm-static-process-manager-configuration>}
25471 @item @code{<php-fpm-on-demand-process-manager-configuration>}
25473 @item @code{display-errors} (default @code{#f})
25474 Determines whether php errors and warning should be sent to clients
25475 and displayed in their browsers.
25476 This is useful for local php development, but a security risk for public sites,
25477 as error messages can reveal passwords and personal data.
25478 @item @code{timezone} (default @code{#f})
25479 Specifies @code{php_admin_value[date.timezone]} parameter.
25480 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
25481 This file will log the @code{stderr} outputs of php worker processes.
25482 Can be set to @code{#f} to disable logging.
25483 @item @code{file} (default @code{#f})
25484 An optional override of the whole configuration.
25485 You can use the @code{mixed-text-file} function or an absolute filepath for it.
25486 @item @code{php-ini-file} (default @code{#f})
25487 An optional override of the default php settings.
25488 It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
25489 You can use the @code{mixed-text-file} function or an absolute filepath for it.
25491 For local development it is useful to set a higher timeout and memory
25492 limit for spawned php processes. This be accomplished with the
25493 following operating system configuration snippet:
25495 (define %local-php-ini
25496 (plain-file "php.ini"
25498 max_execution_time = 1800"))
25502 (services (cons (service php-fpm-service-type
25503 (php-fpm-configuration
25504 (php-ini-file %local-php-ini)))
25508 Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
25509 directives} for comprehensive documentation on the acceptable
25510 @file{php.ini} directives.
25514 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
25515 Data Type for the @code{dynamic} php-fpm process manager. With the
25516 @code{dynamic} process manager, spare worker processes are kept around
25517 based on its configured limits.
25519 @item @code{max-children} (default: @code{5})
25520 Maximum of worker processes.
25521 @item @code{start-servers} (default: @code{2})
25522 How many worker processes should be started on start-up.
25523 @item @code{min-spare-servers} (default: @code{1})
25524 How many spare worker processes should be kept around at minimum.
25525 @item @code{max-spare-servers} (default: @code{3})
25526 How many spare worker processes should be kept around at maximum.
25530 @deftp {Data type} php-fpm-static-process-manager-configuration
25531 Data Type for the @code{static} php-fpm process manager. With the
25532 @code{static} process manager, an unchanging number of worker processes
25535 @item @code{max-children} (default: @code{5})
25536 Maximum of worker processes.
25540 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
25541 Data Type for the @code{on-demand} php-fpm process manager. With the
25542 @code{on-demand} process manager, worker processes are only created as
25545 @item @code{max-children} (default: @code{5})
25546 Maximum of worker processes.
25547 @item @code{process-idle-timeout} (default: @code{10})
25548 The time in seconds after which a process with no requests is killed.
25553 @deffn {Scheme Procedure} nginx-php-location @
25554 [#:nginx-package nginx] @
25555 [socket (string-append "/var/run/php" @
25556 (version-major (package-version php)) @
25558 A helper function to quickly add php to an @code{nginx-server-configuration}.
25561 A simple services setup for nginx with php can look like this:
25563 (services (cons* (service dhcp-client-service-type)
25564 (service php-fpm-service-type)
25565 (service nginx-service-type
25566 (nginx-server-configuration
25567 (server-name '("example.com"))
25568 (root "/srv/http/")
25570 (list (nginx-php-location)))
25572 (ssl-certificate #f)
25573 (ssl-certificate-key #f)))
25577 @cindex cat-avatar-generator
25578 The cat avatar generator is a simple service to demonstrate the use of php-fpm
25579 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
25580 the hash of a user's email address.
25582 @deffn {Scheme Procedure} cat-avatar-generator-service @
25583 [#:cache-dir "/var/cache/cat-avatar-generator"] @
25584 [#:package cat-avatar-generator] @
25585 [#:configuration (nginx-server-configuration)]
25586 Returns an nginx-server-configuration that inherits @code{configuration}. It
25587 extends the nginx configuration to add a server block that serves @code{package},
25588 a version of cat-avatar-generator. During execution, cat-avatar-generator will
25589 be able to use @code{cache-dir} as its cache directory.
25592 A simple setup for cat-avatar-generator can look like this:
25594 (services (cons* (cat-avatar-generator-service
25596 (nginx-server-configuration
25597 (server-name '("example.com"))))
25602 @subsubheading Hpcguix-web
25604 @cindex hpcguix-web
25605 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
25606 program is a customizable web interface to browse Guix packages,
25607 initially designed for users of high-performance computing (HPC)
25610 @defvr {Scheme Variable} hpcguix-web-service-type
25611 The service type for @code{hpcguix-web}.
25614 @deftp {Data Type} hpcguix-web-configuration
25615 Data type for the hpcguix-web service configuration.
25619 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
25620 configuration. The main items available in this spec are:
25623 @item @code{title-prefix} (default: @code{"hpcguix | "})
25624 The page title prefix.
25626 @item @code{guix-command} (default: @code{"guix"})
25627 The @command{guix} command.
25629 @item @code{package-filter-proc} (default: @code{(const #t)})
25630 A procedure specifying how to filter packages that are displayed.
25632 @item @code{package-page-extension-proc} (default: @code{(const '())})
25633 Extension package for @code{hpcguix-web}.
25635 @item @code{menu} (default: @code{'()})
25636 Additional entry in page @code{menu}.
25638 @item @code{channels} (default: @code{%default-channels})
25639 List of channels from which the package list is built (@pxref{Channels}).
25641 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
25642 The expiration time, in seconds, after which the package list is rebuilt from
25643 the latest instances of the given channels.
25646 See the hpcguix-web repository for a
25647 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
25650 @item @code{package} (default: @code{hpcguix-web})
25651 The hpcguix-web package to use.
25655 A typical hpcguix-web service declaration looks like this:
25658 (service hpcguix-web-service-type
25659 (hpcguix-web-configuration
25661 #~(define site-config
25662 (hpcweb-configuration
25663 (title-prefix "Guix-HPC - ")
25664 (menu '(("/about" "ABOUT"))))))))
25668 The hpcguix-web service periodically updates the package list it publishes by
25669 pulling channels from Git. To that end, it needs to access X.509 certificates
25670 so that it can authenticate Git servers when communicating over HTTPS, and it
25671 assumes that @file{/etc/ssl/certs} contains those certificates.
25673 Thus, make sure to add @code{nss-certs} or another certificate package to the
25674 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
25675 more information on X.509 certificates.
25678 @subsubheading gmnisrv
25681 The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
25682 simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
25684 @deffn {Scheme Variable} gmnisrv-service-type
25685 This is the type of the gmnisrv service, whose value should be a
25686 @code{gmnisrv-configuration} object, as in this example:
25689 (service gmnisrv-service-type
25690 (gmnisrv-configuration
25691 (config-file (local-file "./my-gmnisrv.ini"))))
25695 @deftp {Data Type} gmnisrv-configuration
25696 Data type representing the configuration of gmnisrv.
25699 @item @code{package} (default: @var{gmnisrv})
25700 Package object of the gmnisrv server.
25702 @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
25703 File-like object of the gmnisrv configuration file to use. The default
25704 configuration listens on port 1965 and serves files from
25705 @file{/srv/gemini}. Certificates are stored in
25706 @file{/var/lib/gemini/certs}. For more information, run @command{man
25707 gmnisrv} and @command{man gmnisrv.ini}.
25712 @subsubheading Agate
25715 The @uref{gemini://qwertqwefsday.eu/agate.gmi, Agate}
25716 (@uref{https://github.com/mbrubeck/agate, GitHub page over HTTPS})
25717 program is a simple @uref{https://gemini.circumlunar.space/, Gemini}
25718 protocol server written in Rust.
25720 @deffn {Scheme Variable} agate-service-type
25721 This is the type of the agate service, whose value should be an
25722 @code{agate-service-type} object, as in this example:
25725 (service agate-service-type
25726 (agate-configuration
25727 (content "/srv/gemini")
25728 (cert "/srv/cert.pem")
25729 (key "/srv/key.rsa")))
25732 The example above represents the minimal tweaking necessary to get Agate
25733 up and running. Specifying the path to the certificate and key is
25734 always necessary, as the Gemini protocol requires TLS by default.
25736 To obtain a certificate and a key, you could, for example, use OpenSSL,
25737 running a command similar to the following example:
25740 openssl req -x509 -newkey rsa:4096 -keyout key.rsa -out cert.pem \
25741 -days 3650 -nodes -subj "/CN=example.com"
25744 Of course, you'll have to replace @i{example.com} with your own domain
25745 name, and then point the Agate configuration towards the path of the
25746 generated key and certificate.
25750 @deftp {Data Type} agate-configuration
25751 Data type representing the configuration of Agate.
25754 @item @code{package} (default: @code{agate})
25755 The package object of the Agate server.
25757 @item @code{content} (default: @file{"/srv/gemini"})
25758 The directory from which Agate will serve files.
25760 @item @code{cert} (default: @code{#f})
25761 The path to the TLS certificate PEM file to be used for encrypted
25762 connections. Must be filled in with a value from the user.
25764 @item @code{key} (default: @code{#f})
25765 The path to the PKCS8 private key file to be used for encrypted
25766 connections. Must be filled in with a value from the user.
25768 @item @code{addr} (default: @code{'("0.0.0.0:1965" "[::]:1965")})
25769 A list of the addresses to listen on.
25771 @item @code{hostname} (default: @code{#f})
25772 The domain name of this Gemini server. Optional.
25774 @item @code{lang} (default: @code{#f})
25775 RFC 4646 language code(s) for text/gemini documents. Optional.
25777 @item @code{silent?} (default: @code{#f})
25778 Set to @code{#t} to disable logging output.
25780 @item @code{serve-secret?} (default: @code{#f})
25781 Set to @code{#t} to serve secret files (files/directories starting with
25784 @item @code{log-ip?} (default: @code{#t})
25785 Whether or not to output IP addresses when logging.
25787 @item @code{user} (default: @code{"agate"})
25788 Owner of the @code{agate} process.
25790 @item @code{group} (default: @code{"agate"})
25791 Owner's group of the @code{agate} process.
25793 @item @code{log-file} (default: @file{"/var/log/agate.log"})
25794 The file which should store the logging output of Agate.
25799 @node Certificate Services
25800 @subsection Certificate Services
25803 @cindex HTTP, HTTPS
25804 @cindex Let's Encrypt
25805 @cindex TLS certificates
25806 The @code{(gnu services certbot)} module provides a service to
25807 automatically obtain a valid TLS certificate from the Let's Encrypt
25808 certificate authority. These certificates can then be used to serve
25809 content securely over HTTPS or other TLS-based protocols, with the
25810 knowledge that the client will be able to verify the server's
25813 @url{https://letsencrypt.org/, Let's Encrypt} provides the
25814 @code{certbot} tool to automate the certification process. This tool
25815 first securely generates a key on the server. It then makes a request
25816 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
25817 checks that the request originates from the host in question by using a
25818 challenge-response protocol, requiring the server to provide its
25819 response over HTTP@. If that protocol completes successfully, the CA
25820 signs the key, resulting in a certificate. That certificate is valid
25821 for a limited period of time, and therefore to continue to provide TLS
25822 services, the server needs to periodically ask the CA to renew its
25825 The certbot service automates this process: the initial key
25826 generation, the initial certification request to the Let's Encrypt
25827 service, the web server challenge/response integration, writing the
25828 certificate to disk, the automated periodic renewals, and the deployment
25829 tasks associated with the renewal (e.g.@: reloading services, copying keys
25830 with different permissions).
25832 Certbot is run twice a day, at a random minute within the hour. It
25833 won't do anything until your certificates are due for renewal or
25834 revoked, but running it regularly would give your service a chance of
25835 staying online in case a Let's Encrypt-initiated revocation happened for
25838 By using this service, you agree to the ACME Subscriber Agreement, which
25839 can be found there:
25840 @url{https://acme-v01.api.letsencrypt.org/directory}.
25842 @defvr {Scheme Variable} certbot-service-type
25843 A service type for the @code{certbot} Let's Encrypt client. Its value
25844 must be a @code{certbot-configuration} record as in this example:
25847 (define %nginx-deploy-hook
25849 "nginx-deploy-hook"
25850 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
25851 (kill pid SIGHUP))))
25853 (service certbot-service-type
25854 (certbot-configuration
25855 (email "foo@@example.net")
25858 (certificate-configuration
25859 (domains '("example.net" "www.example.net"))
25860 (deploy-hook %nginx-deploy-hook))
25861 (certificate-configuration
25862 (domains '("bar.example.net")))))))
25865 See below for details about @code{certbot-configuration}.
25868 @deftp {Data Type} certbot-configuration
25869 Data type representing the configuration of the @code{certbot} service.
25870 This type has the following parameters:
25873 @item @code{package} (default: @code{certbot})
25874 The certbot package to use.
25876 @item @code{webroot} (default: @code{/var/www})
25877 The directory from which to serve the Let's Encrypt challenge/response
25880 @item @code{certificates} (default: @code{()})
25881 A list of @code{certificates-configuration}s for which to generate
25882 certificates and request signatures. Each certificate has a @code{name}
25883 and several @code{domains}.
25885 @item @code{email} (default: @code{#f})
25886 Optional email address used for registration and recovery contact.
25887 Setting this is encouraged as it allows you to receive important
25888 notifications about the account and issued certificates.
25890 @item @code{server} (default: @code{#f})
25891 Optional URL of ACME server. Setting this overrides certbot's default,
25892 which is the Let's Encrypt server.
25894 @item @code{rsa-key-size} (default: @code{2048})
25895 Size of the RSA key.
25897 @item @code{default-location} (default: @i{see below})
25898 The default @code{nginx-location-configuration}. Because @code{certbot}
25899 needs to be able to serve challenges and responses, it needs to be able
25900 to run a web server. It does so by extending the @code{nginx} web
25901 service with an @code{nginx-server-configuration} listening on the
25902 @var{domains} on port 80, and which has a
25903 @code{nginx-location-configuration} for the @code{/.well-known/} URI
25904 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
25905 these nginx configuration data types.
25907 Requests to other URL paths will be matched by the
25908 @code{default-location}, which if present is added to all
25909 @code{nginx-server-configuration}s.
25911 By default, the @code{default-location} will issue a redirect from
25912 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
25913 you to define what to serve on your site via @code{https}.
25915 Pass @code{#f} to not issue a default location.
25919 @deftp {Data Type} certificate-configuration
25920 Data type representing the configuration of a certificate.
25921 This type has the following parameters:
25924 @item @code{name} (default: @i{see below})
25925 This name is used by Certbot for housekeeping and in file paths; it
25926 doesn't affect the content of the certificate itself. To see
25927 certificate names, run @code{certbot certificates}.
25929 Its default is the first provided domain.
25931 @item @code{domains} (default: @code{()})
25932 The first domain provided will be the subject CN of the certificate, and
25933 all domains will be Subject Alternative Names on the certificate.
25935 @item @code{challenge} (default: @code{#f})
25936 The challenge type that has to be run by certbot. If @code{#f} is specified,
25937 default to the HTTP challenge. If a value is specified, defaults to the
25938 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
25939 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
25940 and gives Let's Encrypt permission to log the public IP address of the
25941 requesting machine.
25943 @item @code{authentication-hook} (default: @code{#f})
25944 Command to be run in a shell once for each certificate challenge to be
25945 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
25946 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
25947 contains the validation string and @code{$CERTBOT_TOKEN} contains the
25948 file name of the resource requested when performing an HTTP-01 challenge.
25950 @item @code{cleanup-hook} (default: @code{#f})
25951 Command to be run in a shell once for each certificate challenge that
25952 have been answered by the @code{auth-hook}. For this command, the shell
25953 variables available in the @code{auth-hook} script are still available, and
25954 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
25955 of the @code{auth-hook} script.
25957 @item @code{deploy-hook} (default: @code{#f})
25958 Command to be run in a shell once for each successfully issued
25959 certificate. For this command, the shell variable
25960 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
25961 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
25962 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
25963 contain a space-delimited list of renewed certificate domains (for
25964 example, @samp{"example.com www.example.com"}.
25969 For each @code{certificate-configuration}, the certificate is saved to
25970 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
25971 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
25973 @subsection DNS Services
25974 @cindex DNS (domain name system)
25975 @cindex domain name system (DNS)
25977 The @code{(gnu services dns)} module provides services related to the
25978 @dfn{domain name system} (DNS). It provides a server service for hosting
25979 an @emph{authoritative} DNS server for multiple zones, slave or master.
25980 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
25981 caching and forwarding DNS server for the LAN, which uses
25982 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
25984 @subsubheading Knot Service
25986 An example configuration of an authoritative server for two zones, one master
25990 (define-zone-entries example.org.zone
25991 ;; Name TTL Class Type Data
25992 ("@@" "" "IN" "A" "127.0.0.1")
25993 ("@@" "" "IN" "NS" "ns")
25994 ("ns" "" "IN" "A" "127.0.0.1"))
25996 (define master-zone
25997 (knot-zone-configuration
25998 (domain "example.org")
26000 (origin "example.org")
26001 (entries example.org.zone)))))
26004 (knot-zone-configuration
26005 (domain "plop.org")
26006 (dnssec-policy "default")
26007 (master (list "plop-master"))))
26009 (define plop-master
26010 (knot-remote-configuration
26012 (address (list "208.76.58.171"))))
26016 (services (cons* (service knot-service-type
26017 (knot-configuration
26018 (remotes (list plop-master))
26019 (zones (list master-zone slave-zone))))
26024 @deffn {Scheme Variable} knot-service-type
26025 This is the type for the Knot DNS server.
26027 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
26028 zones, that is to say domain names you would buy from a registrar. This server
26029 is not a resolver, meaning that it can only resolve names for which it is
26030 authoritative. This server can be configured to serve zones as a master server
26031 or a slave server as a per-zone basis. Slave zones will get their data from
26032 masters, and will serve it as an authoritative server. From the point of view
26033 of a resolver, there is no difference between master and slave.
26035 The following data types are used to configure the Knot DNS server:
26038 @deftp {Data Type} knot-key-configuration
26039 Data type representing a key.
26040 This type has the following parameters:
26043 @item @code{id} (default: @code{""})
26044 An identifier for other configuration fields to refer to this key. IDs must
26045 be unique and must not be empty.
26047 @item @code{algorithm} (default: @code{#f})
26048 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
26049 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
26050 and @code{'hmac-sha512}.
26052 @item @code{secret} (default: @code{""})
26053 The secret key itself.
26058 @deftp {Data Type} knot-acl-configuration
26059 Data type representing an Access Control List (ACL) configuration.
26060 This type has the following parameters:
26063 @item @code{id} (default: @code{""})
26064 An identifier for other configuration fields to refer to this key. IDs must be
26065 unique and must not be empty.
26067 @item @code{address} (default: @code{'()})
26068 An ordered list of IP addresses, network subnets, or network ranges represented
26069 with strings. The query must match one of them. Empty value means that
26070 address match is not required.
26072 @item @code{key} (default: @code{'()})
26073 An ordered list of references to keys represented with strings. The string
26074 must match a key ID defined in a @code{knot-key-configuration}. No key means
26075 that a key is not require to match that ACL.
26077 @item @code{action} (default: @code{'()})
26078 An ordered list of actions that are permitted or forbidden by this ACL@. Possible
26079 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
26080 and @code{'update}.
26082 @item @code{deny?} (default: @code{#f})
26083 When true, the ACL defines restrictions. Listed actions are forbidden. When
26084 false, listed actions are allowed.
26089 @deftp {Data Type} zone-entry
26090 Data type representing a record entry in a zone file.
26091 This type has the following parameters:
26094 @item @code{name} (default: @code{"@@"})
26095 The name of the record. @code{"@@"} refers to the origin of the zone. Names
26096 are relative to the origin of the zone. For example, in the @code{example.org}
26097 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
26098 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
26099 refers to @code{ns.example.org}.
26101 @item @code{ttl} (default: @code{""})
26102 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
26104 @item @code{class} (default: @code{"IN"})
26105 The class of the record. Knot currently supports only @code{"IN"} and
26106 partially @code{"CH"}.
26108 @item @code{type} (default: @code{"A"})
26109 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
26110 address), NS (Name Server) and MX (Mail eXchange). Many other types are
26113 @item @code{data} (default: @code{""})
26114 The data contained in the record. For instance an IP address associated with
26115 an A record, or a domain name associated with an NS record. Remember that
26116 domain names are relative to the origin unless they end with a dot.
26121 @deftp {Data Type} zone-file
26122 Data type representing the content of a zone file.
26123 This type has the following parameters:
26126 @item @code{entries} (default: @code{'()})
26127 The list of entries. The SOA record is taken care of, so you don't need to
26128 put it in the list of entries. This list should probably contain an entry
26129 for your primary authoritative DNS server. Other than using a list of entries
26130 directly, you can use @code{define-zone-entries} to define a object containing
26131 the list of entries more easily, that you can later pass to the @code{entries}
26132 field of the @code{zone-file}.
26134 @item @code{origin} (default: @code{""})
26135 The name of your zone. This parameter cannot be empty.
26137 @item @code{ns} (default: @code{"ns"})
26138 The domain of your primary authoritative DNS server. The name is relative to
26139 the origin, unless it ends with a dot. It is mandatory that this primary
26140 DNS server corresponds to an NS record in the zone and that it is associated
26141 to an IP address in the list of entries.
26143 @item @code{mail} (default: @code{"hostmaster"})
26144 An email address people can contact you at, as the owner of the zone. This
26145 is translated as @code{<mail>@@<origin>}.
26147 @item @code{serial} (default: @code{1})
26148 The serial number of the zone. As this is used to keep track of changes by
26149 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
26150 Always increment it when you make a change in your zone.
26152 @item @code{refresh} (default: @code{(* 2 24 3600)})
26153 The frequency at which slaves will do a zone transfer. This value is a number
26154 of seconds. It can be computed by multiplications or with
26155 @code{(string->duration)}.
26157 @item @code{retry} (default: @code{(* 15 60)})
26158 The period after which a slave will retry to contact its master when it fails
26159 to do so a first time.
26161 @item @code{expiry} (default: @code{(* 14 24 3600)})
26162 Default TTL of records. Existing records are considered correct for at most
26163 this amount of time. After this period, resolvers will invalidate their cache
26164 and check again that it still exists.
26166 @item @code{nx} (default: @code{3600})
26167 Default TTL of inexistent records. This delay is usually short because you want
26168 your new domains to reach everyone quickly.
26173 @deftp {Data Type} knot-remote-configuration
26174 Data type representing a remote configuration.
26175 This type has the following parameters:
26178 @item @code{id} (default: @code{""})
26179 An identifier for other configuration fields to refer to this remote. IDs must
26180 be unique and must not be empty.
26182 @item @code{address} (default: @code{'()})
26183 An ordered list of destination IP addresses. Addresses are tried in sequence.
26184 An optional port can be given with the @@ separator. For instance:
26185 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
26187 @item @code{via} (default: @code{'()})
26188 An ordered list of source IP addresses. An empty list will have Knot choose
26189 an appropriate source IP@. An optional port can be given with the @@ separator.
26190 The default is to choose at random.
26192 @item @code{key} (default: @code{#f})
26193 A reference to a key, that is a string containing the identifier of a key
26194 defined in a @code{knot-key-configuration} field.
26199 @deftp {Data Type} knot-keystore-configuration
26200 Data type representing a keystore to hold dnssec keys.
26201 This type has the following parameters:
26204 @item @code{id} (default: @code{""})
26205 The id of the keystore. It must not be empty.
26207 @item @code{backend} (default: @code{'pem})
26208 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
26210 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
26211 The configuration string of the backend. An example for the PKCS#11 is:
26212 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
26213 For the pem backend, the string represents a path in the file system.
26218 @deftp {Data Type} knot-policy-configuration
26219 Data type representing a dnssec policy. Knot DNS is able to automatically
26220 sign your zones. It can either generate and manage your keys automatically or
26221 use keys that you generate.
26223 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
26224 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
26225 zone. In order to be trusted, the KSK needs to be present in the parent zone
26226 (usually a top-level domain). If your registrar supports dnssec, you will
26227 have to send them your KSK's hash so they can add a DS record in their zone.
26228 This is not automated and need to be done each time you change your KSK.
26230 The policy also defines the lifetime of keys. Usually, ZSK can be changed
26231 easily and use weaker cryptographic functions (they use lower parameters) in
26232 order to sign records quickly, so they are changed often. The KSK however
26233 requires manual interaction with the registrar, so they are changed less often
26234 and use stronger parameters because they sign only one record.
26236 This type has the following parameters:
26239 @item @code{id} (default: @code{""})
26240 The id of the policy. It must not be empty.
26242 @item @code{keystore} (default: @code{"default"})
26243 A reference to a keystore, that is a string containing the identifier of a
26244 keystore defined in a @code{knot-keystore-configuration} field. The
26245 @code{"default"} identifier means the default keystore (a kasp database that
26246 was setup by this service).
26248 @item @code{manual?} (default: @code{#f})
26249 Whether the key management is manual or automatic.
26251 @item @code{single-type-signing?} (default: @code{#f})
26252 When @code{#t}, use the Single-Type Signing Scheme.
26254 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
26255 An algorithm of signing keys and issued signatures.
26257 @item @code{ksk-size} (default: @code{256})
26258 The length of the KSK@. Note that this value is correct for the default
26259 algorithm, but would be unsecure for other algorithms.
26261 @item @code{zsk-size} (default: @code{256})
26262 The length of the ZSK@. Note that this value is correct for the default
26263 algorithm, but would be unsecure for other algorithms.
26265 @item @code{dnskey-ttl} (default: @code{'default})
26266 The TTL value for DNSKEY records added into zone apex. The special
26267 @code{'default} value means same as the zone SOA TTL.
26269 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
26270 The period between ZSK publication and the next rollover initiation.
26272 @item @code{propagation-delay} (default: @code{(* 24 3600)})
26273 An extra delay added for each key rollover step. This value should be high
26274 enough to cover propagation of data from the master server to all slaves.
26276 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
26277 A validity period of newly issued signatures.
26279 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
26280 A period how long before a signature expiration the signature will be refreshed.
26282 @item @code{nsec3?} (default: @code{#f})
26283 When @code{#t}, NSEC3 will be used instead of NSEC.
26285 @item @code{nsec3-iterations} (default: @code{5})
26286 The number of additional times the hashing is performed.
26288 @item @code{nsec3-salt-length} (default: @code{8})
26289 The length of a salt field in octets, which is appended to the original owner
26290 name before hashing.
26292 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
26293 The validity period of newly issued salt field.
26298 @deftp {Data Type} knot-zone-configuration
26299 Data type representing a zone served by Knot.
26300 This type has the following parameters:
26303 @item @code{domain} (default: @code{""})
26304 The domain served by this configuration. It must not be empty.
26306 @item @code{file} (default: @code{""})
26307 The file where this zone is saved. This parameter is ignored by master zones.
26308 Empty means default location that depends on the domain name.
26310 @item @code{zone} (default: @code{(zone-file)})
26311 The content of the zone file. This parameter is ignored by slave zones. It
26312 must contain a zone-file record.
26314 @item @code{master} (default: @code{'()})
26315 A list of master remotes. When empty, this zone is a master. When set, this
26316 zone is a slave. This is a list of remotes identifiers.
26318 @item @code{ddns-master} (default: @code{#f})
26319 The main master. When empty, it defaults to the first master in the list of
26322 @item @code{notify} (default: @code{'()})
26323 A list of slave remote identifiers.
26325 @item @code{acl} (default: @code{'()})
26326 A list of acl identifiers.
26328 @item @code{semantic-checks?} (default: @code{#f})
26329 When set, this adds more semantic checks to the zone.
26331 @item @code{disable-any?} (default: @code{#f})
26332 When set, this forbids queries of the ANY type.
26334 @item @code{zonefile-sync} (default: @code{0})
26335 The delay between a modification in memory and on disk. 0 means immediate
26338 @item @code{zonefile-load} (default: @code{#f})
26339 The way the zone file contents are applied during zone load. Possible values
26343 @item @code{#f} for using the default value from Knot,
26344 @item @code{'none} for not using the zone file at all,
26345 @item @code{'difference} for computing the difference between already available
26346 contents and zone contents and applying it to the current zone contents,
26347 @item @code{'difference-no-serial} for the same as @code{'difference}, but
26348 ignoring the SOA serial in the zone file, while the server takes care of it
26350 @item @code{'whole} for loading zone contents from the zone file.
26353 @item @code{journal-content} (default: @code{#f})
26354 The way the journal is used to store zone and its changes. Possible values
26355 are @code{'none} to not use it at all, @code{'changes} to store changes and
26356 @code{'all} to store contents. @code{#f} does not set this option, so the
26357 default value from Knot is used.
26359 @item @code{max-journal-usage} (default: @code{#f})
26360 The maximum size for the journal on disk. @code{#f} does not set this option,
26361 so the default value from Knot is used.
26363 @item @code{max-journal-depth} (default: @code{#f})
26364 The maximum size of the history. @code{#f} does not set this option, so the
26365 default value from Knot is used.
26367 @item @code{max-zone-size} (default: @code{#f})
26368 The maximum size of the zone file. This limit is enforced for incoming
26369 transfer and updates. @code{#f} does not set this option, so the default
26370 value from Knot is used.
26372 @item @code{dnssec-policy} (default: @code{#f})
26373 A reference to a @code{knot-policy-configuration} record, or the special
26374 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
26377 @item @code{serial-policy} (default: @code{'increment})
26378 A policy between @code{'increment} and @code{'unixtime}.
26383 @deftp {Data Type} knot-configuration
26384 Data type representing the Knot configuration.
26385 This type has the following parameters:
26388 @item @code{knot} (default: @code{knot})
26391 @item @code{run-directory} (default: @code{"/var/run/knot"})
26392 The run directory. This directory will be used for pid file and sockets.
26394 @item @code{includes} (default: @code{'()})
26395 A list of strings or file-like objects denoting other files that must be
26396 included at the top of the configuration file.
26398 @cindex secrets, Knot service
26399 This can be used to manage secrets out-of-band. For example, secret
26400 keys may be stored in an out-of-band file not managed by Guix, and
26401 thus not visible in @file{/gnu/store}---e.g., you could store secret
26402 key configuration in @file{/etc/knot/secrets.conf} and add this file
26403 to the @code{includes} list.
26405 One can generate a secret tsig key (for nsupdate and zone transfers with the
26406 keymgr command from the knot package. Note that the package is not automatically
26407 installed by the service. The following example shows how to generate a new
26411 keymgr -t mysecret > /etc/knot/secrets.conf
26412 chmod 600 /etc/knot/secrets.conf
26415 Also note that the generated key will be named @var{mysecret}, so it is the
26416 name that needs to be used in the @var{key} field of the
26417 @code{knot-acl-configuration} record and in other places that need to refer
26420 It can also be used to add configuration not supported by this interface.
26422 @item @code{listen-v4} (default: @code{"0.0.0.0"})
26423 An ip address on which to listen.
26425 @item @code{listen-v6} (default: @code{"::"})
26426 An ip address on which to listen.
26428 @item @code{listen-port} (default: @code{53})
26429 A port on which to listen.
26431 @item @code{keys} (default: @code{'()})
26432 The list of knot-key-configuration used by this configuration.
26434 @item @code{acls} (default: @code{'()})
26435 The list of knot-acl-configuration used by this configuration.
26437 @item @code{remotes} (default: @code{'()})
26438 The list of knot-remote-configuration used by this configuration.
26440 @item @code{zones} (default: @code{'()})
26441 The list of knot-zone-configuration used by this configuration.
26446 @subsubheading Knot Resolver Service
26448 @deffn {Scheme Variable} knot-resolver-service-type
26449 This is the type of the knot resolver service, whose value should be
26450 an @code{knot-resolver-configuration} object as in this example:
26453 (service knot-resolver-service-type
26454 (knot-resolver-configuration
26455 (kresd-config-file (plain-file "kresd.conf" "
26456 net.listen('192.168.0.1', 5353)
26457 user('knot-resolver', 'knot-resolver')
26458 modules = @{ 'hints > iterate', 'stats', 'predict' @}
26459 cache.size = 100 * MB
26463 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
26466 @deftp {Data Type} knot-resolver-configuration
26467 Data type representing the configuration of knot-resolver.
26470 @item @code{package} (default: @var{knot-resolver})
26471 Package object of the knot DNS resolver.
26473 @item @code{kresd-config-file} (default: %kresd.conf)
26474 File-like object of the kresd configuration file to use, by default it
26475 will listen on @code{127.0.0.1} and @code{::1}.
26477 @item @code{garbage-collection-interval} (default: 1000)
26478 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
26484 @subsubheading Dnsmasq Service
26486 @deffn {Scheme Variable} dnsmasq-service-type
26487 This is the type of the dnsmasq service, whose value should be an
26488 @code{dnsmasq-configuration} object as in this example:
26491 (service dnsmasq-service-type
26492 (dnsmasq-configuration
26494 (servers '("192.168.1.1"))))
26498 @deftp {Data Type} dnsmasq-configuration
26499 Data type representing the configuration of dnsmasq.
26502 @item @code{package} (default: @var{dnsmasq})
26503 Package object of the dnsmasq server.
26505 @item @code{no-hosts?} (default: @code{#f})
26506 When true, don't read the hostnames in /etc/hosts.
26508 @item @code{port} (default: @code{53})
26509 The port to listen on. Setting this to zero completely disables DNS
26510 responses, leaving only DHCP and/or TFTP functions.
26512 @item @code{local-service?} (default: @code{#t})
26513 Accept DNS queries only from hosts whose address is on a local subnet,
26514 ie a subnet for which an interface exists on the server.
26516 @item @code{listen-addresses} (default: @code{'()})
26517 Listen on the given IP addresses.
26519 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
26520 The file to read the IP address of the upstream nameservers from.
26522 @item @code{no-resolv?} (default: @code{#f})
26523 When true, don't read @var{resolv-file}.
26525 @item @code{servers} (default: @code{'()})
26526 Specify IP address of upstream servers directly.
26528 @item @code{addresses} (default: @code{'()})
26529 For each entry, specify an IP address to return for any host in the
26530 given domains. Queries in the domains are never forwarded and always
26531 replied to with the specified IP address.
26533 This is useful for redirecting hosts locally, for example:
26536 (service dnsmasq-service-type
26537 (dnsmasq-configuration
26539 '(; Redirect to a local web-server.
26540 "/example.org/127.0.0.1"
26541 ; Redirect subdomain to a specific IP.
26542 "/subdomain.example.org/192.168.1.42"))))
26545 Note that rules in @file{/etc/hosts} take precedence over this.
26547 @item @code{cache-size} (default: @code{150})
26548 Set the size of dnsmasq's cache. Setting the cache size to zero
26551 @item @code{negative-cache?} (default: @code{#t})
26552 When false, disable negative caching.
26554 @item @code{tftp-enable?} (default: @code{#f})
26555 Whether to enable the built-in TFTP server.
26557 @item @code{tftp-no-fail?} (default: @code{#f})
26558 If true, does not fail dnsmasq if the TFTP server could not start up.
26560 @item @code{tftp-single-port?} (default: @code{#f})
26561 Whether to use only one single port for TFTP.
26563 @item @code{tftp-secure?} (default: @code{#f})
26564 If true, only files owned by the user running the dnsmasq process are accessible.
26566 If dnsmasq is being run as root, different rules apply:
26567 @code{tftp-secure?} has no effect, but only files which have the
26568 world-readable bit set are accessible.
26570 @item @code{tftp-max} (default: @code{#f})
26571 If set, sets the maximal number of concurrent connections allowed.
26573 @item @code{tftp-mtu} (default: @code{#f})
26574 If set, sets the MTU for TFTP packets to that value.
26576 @item @code{tftp-no-blocksize?} (default: @code{#f})
26577 If true, stops the TFTP server from negotiating the blocksize with a client.
26579 @item @code{tftp-lowercase?} (default: @code{#f})
26580 Whether to convert all filenames in TFTP requests to lowercase.
26582 @item @code{tftp-port-range} (default: @code{#f})
26583 If set, fixes the dynamical ports (one per client) to the given range
26584 (@code{"<start>,<end>"}).
26586 @item @code{tftp-root} (default: @code{/var/empty,lo})
26587 Look for files to transfer using TFTP relative to the given directory.
26588 When this is set, TFTP paths which include @samp{..} are rejected, to stop clients
26589 getting outside the specified root. Absolute paths (starting with @samp{/}) are
26590 allowed, but they must be within the TFTP-root. If the optional interface
26591 argument is given, the directory is only used for TFTP requests via that
26594 @item @code{tftp-unique-root} (default: @code{#f})
26595 If set, add the IP or hardware address of the TFTP client as a path component
26596 on the end of the TFTP-root. Only valid if a TFTP root is set and the
26597 directory exists. Defaults to adding IP address (in standard dotted-quad
26600 For instance, if @option{--tftp-root} is @samp{/tftp} and client
26601 @samp{1.2.3.4} requests file @file{myfile} then the effective path will
26602 be @file{/tftp/1.2.3.4/myfile} if @file{/tftp/1.2.3.4} exists or
26603 @file{/tftp/myfile} otherwise. When @samp{=mac} is specified it will
26604 append the MAC address instead, using lowercase zero padded digits
26605 separated by dashes, e.g.: @samp{01-02-03-04-aa-bb}. Note that
26606 resolving MAC addresses is only possible if the client is in the local
26607 network or obtained a DHCP lease from dnsmasq.
26612 @subsubheading ddclient Service
26615 The ddclient service described below runs the ddclient daemon, which takes
26616 care of automatically updating DNS entries for service providers such as
26617 @uref{https://dyn.com/dns/, Dyn}.
26619 The following example show instantiates the service with its default
26623 (service ddclient-service-type)
26626 Note that ddclient needs to access credentials that are stored in a
26627 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
26628 @code{secret-file} below). You are expected to create this file manually, in
26629 an ``out-of-band'' fashion (you @emph{could} make this file part of the
26630 service configuration, for instance by using @code{plain-file}, but it will be
26631 world-readable @i{via} @file{/gnu/store}). See the examples in the
26632 @file{share/ddclient} directory of the @code{ddclient} package.
26634 @c %start of fragment
26636 Available @code{ddclient-configuration} fields are:
26638 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
26639 The ddclient package.
26643 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
26644 The period after which ddclient will retry to check IP and domain name.
26646 Defaults to @samp{300}.
26650 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
26651 Use syslog for the output.
26653 Defaults to @samp{#t}.
26657 @deftypevr {@code{ddclient-configuration} parameter} string mail
26660 Defaults to @samp{"root"}.
26664 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
26665 Mail failed update to user.
26667 Defaults to @samp{"root"}.
26671 @deftypevr {@code{ddclient-configuration} parameter} string pid
26672 The ddclient PID file.
26674 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
26678 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
26679 Enable SSL support.
26681 Defaults to @samp{#t}.
26685 @deftypevr {@code{ddclient-configuration} parameter} string user
26686 Specifies the user name or ID that is used when running ddclient
26689 Defaults to @samp{"ddclient"}.
26693 @deftypevr {@code{ddclient-configuration} parameter} string group
26694 Group of the user who will run the ddclient program.
26696 Defaults to @samp{"ddclient"}.
26700 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
26701 Secret file which will be appended to @file{ddclient.conf} file. This
26702 file contains credentials for use by ddclient. You are expected to
26703 create it manually.
26705 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
26709 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
26710 Extra options will be appended to @file{ddclient.conf} file.
26712 Defaults to @samp{()}.
26717 @c %end of fragment
26721 @subsection VPN Services
26722 @cindex VPN (virtual private network)
26723 @cindex virtual private network (VPN)
26725 The @code{(gnu services vpn)} module provides services related to
26726 @dfn{virtual private networks} (VPNs).
26728 @subsubheading OpenVPN
26730 It provides a @emph{client} service for your machine to connect to a
26731 VPN, and a @emph{server} service for your machine to host a VPN@.
26733 @deffn {Scheme Procedure} openvpn-client-service @
26734 [#:config (openvpn-client-configuration)]
26736 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
26739 @deffn {Scheme Procedure} openvpn-server-service @
26740 [#:config (openvpn-server-configuration)]
26742 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
26744 Both can be run simultaneously.
26747 @c %automatically generated documentation
26749 Available @code{openvpn-client-configuration} fields are:
26751 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
26752 The OpenVPN package.
26756 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
26757 The OpenVPN pid file.
26759 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
26763 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
26764 The protocol (UDP or TCP) used to open a channel between clients and
26767 Defaults to @samp{udp}.
26771 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
26772 The device type used to represent the VPN connection.
26774 Defaults to @samp{tun}.
26778 If you do not have some of these files (eg.@: you use a username and
26779 password), you can disable any of the following three fields by setting
26780 it to @code{'disabled}.
26782 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string ca
26783 The certificate authority to check connections against.
26785 Defaults to @samp{"/etc/openvpn/ca.crt"}.
26789 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string cert
26790 The certificate of the machine the daemon is running on. It should be
26791 signed by the authority given in @code{ca}.
26793 Defaults to @samp{"/etc/openvpn/client.crt"}.
26797 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string key
26798 The key of the machine the daemon is running on. It must be the key whose
26799 certificate is @code{cert}.
26801 Defaults to @samp{"/etc/openvpn/client.key"}.
26805 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
26806 Whether to use the lzo compression algorithm.
26808 Defaults to @samp{#t}.
26812 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
26813 Don't re-read key files across SIGUSR1 or --ping-restart.
26815 Defaults to @samp{#t}.
26819 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
26820 Don't close and reopen TUN/TAP device or run up/down scripts across
26821 SIGUSR1 or --ping-restart restarts.
26823 Defaults to @samp{#t}.
26827 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
26828 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
26829 poll/epoll/select prior to the write operation.
26831 Defaults to @samp{#f}.
26834 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
26837 Defaults to @samp{3}.
26841 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
26842 Add an additional layer of HMAC authentication on top of the TLS control
26843 channel to protect against DoS attacks.
26845 Defaults to @samp{#f}.
26849 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
26850 Authenticate with server using username/password. The option is a file
26851 containing username/password on 2 lines. Do not use a file-like object as it
26852 would be added to the store and readable by any user.
26854 Defaults to @samp{'disabled}.
26857 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
26858 Whether to check the server certificate has server usage extension.
26860 Defaults to @samp{#t}.
26864 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
26865 Bind to a specific local port number.
26867 Defaults to @samp{#f}.
26871 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
26872 Retry resolving server address.
26874 Defaults to @samp{#t}.
26878 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
26879 A list of remote servers to connect to.
26881 Defaults to @samp{()}.
26883 Available @code{openvpn-remote-configuration} fields are:
26885 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
26888 Defaults to @samp{"my-server"}.
26892 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
26893 Port number the server listens to.
26895 Defaults to @samp{1194}.
26900 @c %end of automatic openvpn-client documentation
26902 @c %automatically generated documentation
26904 Available @code{openvpn-server-configuration} fields are:
26906 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
26907 The OpenVPN package.
26911 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
26912 The OpenVPN pid file.
26914 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
26918 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
26919 The protocol (UDP or TCP) used to open a channel between clients and
26922 Defaults to @samp{udp}.
26926 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
26927 The device type used to represent the VPN connection.
26929 Defaults to @samp{tun}.
26933 If you do not have some of these files (eg.@: you use a username and
26934 password), you can disable any of the following three fields by setting
26935 it to @code{'disabled}.
26937 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string ca
26938 The certificate authority to check connections against.
26940 Defaults to @samp{"/etc/openvpn/ca.crt"}.
26944 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string cert
26945 The certificate of the machine the daemon is running on. It should be
26946 signed by the authority given in @code{ca}.
26948 Defaults to @samp{"/etc/openvpn/client.crt"}.
26952 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string key
26953 The key of the machine the daemon is running on. It must be the key whose
26954 certificate is @code{cert}.
26956 Defaults to @samp{"/etc/openvpn/client.key"}.
26960 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
26961 Whether to use the lzo compression algorithm.
26963 Defaults to @samp{#t}.
26967 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
26968 Don't re-read key files across SIGUSR1 or --ping-restart.
26970 Defaults to @samp{#t}.
26974 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
26975 Don't close and reopen TUN/TAP device or run up/down scripts across
26976 SIGUSR1 or --ping-restart restarts.
26978 Defaults to @samp{#t}.
26982 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
26983 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
26984 poll/epoll/select prior to the write operation.
26986 Defaults to @samp{#f}.
26989 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
26992 Defaults to @samp{3}.
26996 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
26997 Add an additional layer of HMAC authentication on top of the TLS control
26998 channel to protect against DoS attacks.
27000 Defaults to @samp{#f}.
27004 @deftypevr {@code{openvpn-server-configuration} parameter} number port
27005 Specifies the port number on which the server listens.
27007 Defaults to @samp{1194}.
27011 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
27012 An ip and mask specifying the subnet inside the virtual network.
27014 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
27018 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
27019 A CIDR notation specifying the IPv6 subnet inside the virtual network.
27021 Defaults to @samp{#f}.
27025 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
27026 The Diffie-Hellman parameters file.
27028 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
27032 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
27033 The file that records client IPs.
27035 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
27039 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
27040 When true, the server will act as a gateway for its clients.
27042 Defaults to @samp{#f}.
27046 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
27047 When true, clients are allowed to talk to each other inside the VPN.
27049 Defaults to @samp{#f}.
27053 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
27054 Causes ping-like messages to be sent back and forth over the link so
27055 that each side knows when the other side has gone down. @code{keepalive}
27056 requires a pair. The first element is the period of the ping sending,
27057 and the second element is the timeout before considering the other side
27062 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
27063 The maximum number of clients.
27065 Defaults to @samp{100}.
27069 @deftypevr {@code{openvpn-server-configuration} parameter} string status
27070 The status file. This file shows a small report on current connection.
27071 It is truncated and rewritten every minute.
27073 Defaults to @samp{"/var/run/openvpn/status"}.
27077 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
27078 The list of configuration for some clients.
27080 Defaults to @samp{()}.
27082 Available @code{openvpn-ccd-configuration} fields are:
27084 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
27087 Defaults to @samp{"client"}.
27091 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
27094 Defaults to @samp{#f}.
27098 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
27101 Defaults to @samp{#f}.
27108 @c %end of automatic openvpn-server documentation
27110 @subsubheading Wireguard
27112 @defvr {Scheme Variable} wireguard-service-type
27113 A service type for a Wireguard tunnel interface. Its value must be a
27114 @code{wireguard-configuration} record as in this example:
27117 (service wireguard-service-type
27118 (wireguard-configuration
27123 (endpoint "my.wireguard.com:51820")
27124 (public-key "hzpKg9X1yqu1axN6iJp0mWf6BZGo8m1wteKwtTmDGF4=")
27125 (allowed-ips '("10.0.0.2/32")))))))
27130 @deftp {Data Type} wireguard-configuration
27131 Data type representing the configuration of the Wireguard service.
27134 @item @code{wireguard}
27135 The wireguard package to use for this service.
27137 @item @code{interface} (default: @code{"wg0"})
27138 The interface name for the VPN.
27140 @item @code{addresses} (default: @code{'("10.0.0.1/32")})
27141 The IP addresses to be assigned to the above interface.
27143 @item @code{private-key} (default: @code{"/etc/wireguard/private.key"})
27144 The private key file for the interface. It is automatically generated if
27145 the file does not exist.
27147 @item @code{peers} (default: @code{'()})
27148 The authorized peers on this interface. This is a list of
27149 @var{wireguard-peer} records.
27154 @deftp {Data Type} wireguard-peer
27155 Data type representing a Wireguard peer attached to a given interface.
27161 @item @code{endpoint} (default: @code{#f})
27162 The optional endpoint for the peer, such as
27163 @code{"demo.wireguard.com:51820"}.
27165 @item @code{public-key}
27166 The peer public-key represented as a base64 string.
27168 @item @code{allowed-ips}
27169 A list of IP addresses from which incoming traffic for this peer is
27170 allowed and to which incoming traffic for this peer is directed.
27172 @item @code{keep-alive} (default: @code{#f})
27173 An optional time interval in seconds. A packet will be sent to the
27174 server endpoint once per time interval. This helps receiving
27175 incoming connections from this peer when you are behind a NAT or
27181 @node Network File System
27182 @subsection Network File System
27185 The @code{(gnu services nfs)} module provides the following services,
27186 which are most commonly used in relation to mounting or exporting
27187 directory trees as @dfn{network file systems} (NFS).
27189 While it is possible to use the individual components that together make
27190 up a Network File System service, we recommended to configure an NFS
27191 server with the @code{nfs-service-type}.
27193 @subsubheading NFS Service
27194 @cindex NFS, server
27196 The NFS service takes care of setting up all NFS component services,
27197 kernel configuration file systems, and installs configuration files in
27198 the locations that NFS expects.
27200 @defvr {Scheme Variable} nfs-service-type
27201 A service type for a complete NFS server.
27204 @deftp {Data Type} nfs-configuration
27205 This data type represents the configuration of the NFS service and all
27208 It has the following parameters:
27210 @item @code{nfs-utils} (default: @code{nfs-utils})
27211 The nfs-utils package to use.
27213 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
27214 If a list of string values is provided, the @command{rpc.nfsd} daemon
27215 will be limited to supporting the given versions of the NFS protocol.
27217 @item @code{exports} (default: @code{'()})
27218 This is a list of directories the NFS server should export. Each entry
27219 is a list consisting of two elements: a directory name and a string
27220 containing all options. This is an example in which the directory
27221 @file{/export} is served to all NFS clients as a read-only share:
27227 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
27230 @item @code{rpcmountd-port} (default: @code{#f})
27231 The network port that the @command{rpc.mountd} daemon should use.
27233 @item @code{rpcstatd-port} (default: @code{#f})
27234 The network port that the @command{rpc.statd} daemon should use.
27236 @item @code{rpcbind} (default: @code{rpcbind})
27237 The rpcbind package to use.
27239 @item @code{idmap-domain} (default: @code{"localdomain"})
27240 The local NFSv4 domain name.
27242 @item @code{nfsd-port} (default: @code{2049})
27243 The network port that the @command{nfsd} daemon should use.
27245 @item @code{nfsd-threads} (default: @code{8})
27246 The number of threads used by the @command{nfsd} daemon.
27248 @item @code{nfsd-tcp?} (default: @code{#t})
27249 Whether the @command{nfsd} daemon should listen on a TCP socket.
27251 @item @code{nfsd-udp?} (default: @code{#f})
27252 Whether the @command{nfsd} daemon should listen on a UDP socket.
27254 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
27255 The directory where the pipefs file system is mounted.
27257 @item @code{debug} (default: @code{'()"})
27258 A list of subsystems for which debugging output should be enabled. This
27259 is a list of symbols. Any of these symbols are valid: @code{nfsd},
27260 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
27264 If you don't need a complete NFS service or prefer to build it yourself
27265 you can use the individual component services that are documented below.
27267 @subsubheading RPC Bind Service
27270 The RPC Bind service provides a facility to map program numbers into
27271 universal addresses.
27272 Many NFS related services use this facility. Hence it is automatically
27273 started when a dependent service starts.
27275 @defvr {Scheme Variable} rpcbind-service-type
27276 A service type for the RPC portmapper daemon.
27280 @deftp {Data Type} rpcbind-configuration
27281 Data type representing the configuration of the RPC Bind Service.
27282 This type has the following parameters:
27284 @item @code{rpcbind} (default: @code{rpcbind})
27285 The rpcbind package to use.
27287 @item @code{warm-start?} (default: @code{#t})
27288 If this parameter is @code{#t}, then the daemon will read a
27289 state file on startup thus reloading state information saved by a previous
27295 @subsubheading Pipefs Pseudo File System
27299 The pipefs file system is used to transfer NFS related data
27300 between the kernel and user space programs.
27302 @defvr {Scheme Variable} pipefs-service-type
27303 A service type for the pipefs pseudo file system.
27306 @deftp {Data Type} pipefs-configuration
27307 Data type representing the configuration of the pipefs pseudo file system service.
27308 This type has the following parameters:
27310 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
27311 The directory to which the file system is to be attached.
27316 @subsubheading GSS Daemon Service
27319 @cindex global security system
27321 The @dfn{global security system} (GSS) daemon provides strong security for RPC
27323 Before exchanging RPC requests an RPC client must establish a security
27324 context. Typically this is done using the Kerberos command @command{kinit}
27325 or automatically at login time using PAM services (@pxref{Kerberos Services}).
27327 @defvr {Scheme Variable} gss-service-type
27328 A service type for the Global Security System (GSS) daemon.
27331 @deftp {Data Type} gss-configuration
27332 Data type representing the configuration of the GSS daemon service.
27333 This type has the following parameters:
27335 @item @code{nfs-utils} (default: @code{nfs-utils})
27336 The package in which the @command{rpc.gssd} command is to be found.
27338 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
27339 The directory where the pipefs file system is mounted.
27345 @subsubheading IDMAP Daemon Service
27347 @cindex name mapper
27349 The idmap daemon service provides mapping between user IDs and user names.
27350 Typically it is required in order to access file systems mounted via NFSv4.
27352 @defvr {Scheme Variable} idmap-service-type
27353 A service type for the Identity Mapper (IDMAP) daemon.
27356 @deftp {Data Type} idmap-configuration
27357 Data type representing the configuration of the IDMAP daemon service.
27358 This type has the following parameters:
27360 @item @code{nfs-utils} (default: @code{nfs-utils})
27361 The package in which the @command{rpc.idmapd} command is to be found.
27363 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
27364 The directory where the pipefs file system is mounted.
27366 @item @code{domain} (default: @code{#f})
27367 The local NFSv4 domain name.
27368 This must be a string or @code{#f}.
27369 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
27371 @item @code{verbosity} (default: @code{0})
27372 The verbosity level of the daemon.
27377 @node Continuous Integration
27378 @subsection Continuous Integration
27380 @cindex continuous integration
27381 @uref{https://guix.gnu.org/cuirass/, Cuirass} is a continuous
27382 integration tool for Guix. It can be used both for development and for
27383 providing substitutes to others (@pxref{Substitutes}).
27385 The @code{(gnu services cuirass)} module provides the following service.
27387 @defvr {Scheme Procedure} cuirass-service-type
27388 The type of the Cuirass service. Its value must be a
27389 @code{cuirass-configuration} object, as described below.
27392 To add build jobs, you have to set the @code{specifications} field of
27393 the configuration. For instance, the following example will build all
27394 the packages provided by the @code{my-channel} channel.
27397 (define %cuirass-specs
27398 #~(list (specification
27399 (name "my-channel")
27400 (build '(channels my-channel))
27404 (url "https://my-channel.git"))
27405 %default-channels)))))
27407 (service cuirass-service-type
27408 (cuirass-configuration
27409 (specifications %cuirass-specs)))
27412 To build the @code{linux-libre} package defined by the default Guix
27413 channel, one can use the following configuration.
27416 (define %cuirass-specs
27417 #~(list (specification
27419 (build '(packages "linux-libre")))))
27421 (service cuirass-service-type
27422 (cuirass-configuration
27423 (specifications %cuirass-specs)))
27426 The other configuration possibilities, as well as the specification
27427 record itself are described in the Cuirass manual
27428 (@pxref{Specifications,,, cuirass, Cuirass}).
27430 While information related to build jobs is located directly in the
27431 specifications, global settings for the @command{cuirass} process are
27432 accessible in other @code{cuirass-configuration} fields.
27434 @deftp {Data Type} cuirass-configuration
27435 Data type representing the configuration of Cuirass.
27438 @item @code{cuirass} (default: @code{cuirass})
27439 The Cuirass package to use.
27441 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
27442 Location of the log file.
27444 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
27445 Location of the log file used by the web interface.
27447 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
27448 Location of the repository cache.
27450 @item @code{user} (default: @code{"cuirass"})
27451 Owner of the @code{cuirass} process.
27453 @item @code{group} (default: @code{"cuirass"})
27454 Owner's group of the @code{cuirass} process.
27456 @item @code{interval} (default: @code{60})
27457 Number of seconds between the poll of the repositories followed by the
27460 @item @code{parameters} (default: @code{#f})
27461 Read parameters from the given @var{parameters} file. The supported
27462 parameters are described here (@pxref{Parameters,,, cuirass, Cuirass}).
27464 @item @code{remote-server} (default: @code{#f})
27465 A @code{cuirass-remote-server-configuration} record to use the build
27466 remote mechanism or @code{#f} to use the default build mechanism.
27468 @item @code{database} (default: @code{"dbname=cuirass host=/var/run/postgresql"})
27469 Use @var{database} as the database containing the jobs and the past
27470 build results. Since Cuirass uses PostgreSQL as a database engine,
27471 @var{database} must be a string such as @code{"dbname=cuirass
27474 @item @code{port} (default: @code{8081})
27475 Port number used by the HTTP server.
27477 @item @code{host} (default: @code{"localhost"})
27478 Listen on the network interface for @var{host}. The default is to
27479 accept connections from localhost.
27481 @item @code{specifications} (default: @code{#~'()})
27482 A gexp (@pxref{G-Expressions}) that evaluates to a list of
27483 specifications records. The specification record is described in the
27484 Cuirass manual (@pxref{Specifications,,, cuirass, Cuirass}).
27486 @item @code{use-substitutes?} (default: @code{#f})
27487 This allows using substitutes to avoid building every dependencies of a job
27490 @item @code{one-shot?} (default: @code{#f})
27491 Only evaluate specifications and build derivations once.
27493 @item @code{fallback?} (default: @code{#f})
27494 When substituting a pre-built binary fails, fall back to building
27497 @item @code{extra-options} (default: @code{'()})
27498 Extra options to pass when running the Cuirass processes.
27503 @cindex remote build
27504 @subsubheading Cuirass remote building
27506 Cuirass supports two mechanisms to build derivations.
27509 @item Using the local Guix daemon.
27510 This is the default build mechanism. Once the build jobs are
27511 evaluated, they are sent to the local Guix daemon. Cuirass then
27512 listens to the Guix daemon output to detect the various build events.
27514 @item Using the remote build mechanism.
27515 The build jobs are not submitted to the local Guix daemon. Instead, a
27516 remote server dispatches build requests to the connect remote workers,
27517 according to the build priorities.
27521 To enable this build mode a @code{cuirass-remote-server-configuration}
27522 record must be passed as @code{remote-server} argument of the
27523 @code{cuirass-configuration} record. The
27524 @code{cuirass-remote-server-configuration} record is described below.
27526 This build mode scales way better than the default build mode. This is
27527 the build mode that is used on the GNU Guix build farm at
27528 @url{https://ci.guix.gnu.org}. It should be preferred when using
27529 Cuirass to build large amount of packages.
27531 @deftp {Data Type} cuirass-remote-server-configuration
27532 Data type representing the configuration of the Cuirass remote-server.
27535 @item @code{backend-port} (default: @code{5555})
27536 The TCP port for communicating with @code{remote-worker} processes
27537 using ZMQ. It defaults to @code{5555}.
27539 @item @code{log-port} (default: @code{5556})
27540 The TCP port of the log server. It defaults to @code{5556}.
27542 @item @code{publish-port} (default: @code{5557})
27543 The TCP port of the publish server. It defaults to @code{5557}.
27545 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-server.log"})
27546 Location of the log file.
27548 @item @code{cache} (default: @code{"/var/cache/cuirass/remote"})
27549 Use @var{cache} directory to cache build log files.
27551 @item @code{trigger-url} (default: @code{#f})
27552 Once a substitute is successfully fetched, trigger substitute baking at
27555 @item @code{public-key}
27556 @item @code{private-key}
27557 Use the specific @var{file}s as the public/private key pair used to sign
27558 the store items being published.
27563 At least one remote worker must also be started on any machine of the
27564 local network to actually perform the builds and report their status.
27566 @deftp {Data Type} cuirass-remote-worker-configuration
27567 Data type representing the configuration of the Cuirass remote-worker.
27570 @item @code{cuirass} (default: @code{cuirass})
27571 The Cuirass package to use.
27573 @item @code{workers} (default: @code{1})
27574 Start @var{workers} parallel workers.
27576 @item @code{server} (default: @code{#f})
27577 Do not use Avahi discovery and connect to the given @code{server} IP
27580 @item @code{systems} (default: @code{(list (%current-system))})
27581 Only request builds for the given @var{systems}.
27583 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-worker.log"})
27584 Location of the log file.
27586 @item @code{publish-port} (default: @code{5558})
27587 The TCP port of the publish server. It defaults to @code{5558}.
27589 @item @code{public-key}
27590 @item @code{private-key}
27591 Use the specific @var{file}s as the public/private key pair used to sign
27592 the store items being published.
27597 @subsubheading Laminar
27599 @uref{https://laminar.ohwg.net/, Laminar} is a lightweight and modular
27600 Continuous Integration service. It doesn't have a configuration web UI
27601 instead uses version-controllable configuration files and scripts.
27603 Laminar encourages the use of existing tools such as bash and cron
27604 instead of reinventing them.
27606 @defvr {Scheme Procedure} laminar-service-type
27607 The type of the Laminar service. Its value must be a
27608 @code{laminar-configuration} object, as described below.
27610 All configuration values have defaults, a minimal configuration to get
27611 Laminar running is shown below. By default, the web interface is
27612 available on port 8080.
27615 (service laminar-service-type)
27619 @deftp {Data Type} laminar-configuration
27620 Data type representing the configuration of Laminar.
27623 @item @code{laminar} (default: @code{laminar})
27624 The Laminar package to use.
27626 @item @code{home-directory} (default: @code{"/var/lib/laminar"})
27627 The directory for job configurations and run directories.
27629 @item @code{bind-http} (default: @code{"*:8080"})
27630 The interface/port or unix socket on which laminard should listen for
27631 incoming connections to the web frontend.
27633 @item @code{bind-rpc} (default: @code{"unix-abstract:laminar"})
27634 The interface/port or unix socket on which laminard should listen for
27635 incoming commands such as build triggers.
27637 @item @code{title} (default: @code{"Laminar"})
27638 The page title to show in the web frontend.
27640 @item @code{keep-rundirs} (default: @code{0})
27641 Set to an integer defining how many rundirs to keep per job. The
27642 lowest-numbered ones will be deleted. The default is 0, meaning all run
27643 dirs will be immediately deleted.
27645 @item @code{archive-url} (default: @code{#f})
27646 The web frontend served by laminard will use this URL to form links to
27647 artefacts archived jobs.
27649 @item @code{base-url} (default: @code{#f})
27650 Base URL to use for links to laminar itself.
27655 @node Power Management Services
27656 @subsection Power Management Services
27659 @cindex power management with TLP
27660 @subsubheading TLP daemon
27662 The @code{(gnu services pm)} module provides a Guix service definition
27663 for the Linux power management tool TLP.
27665 TLP enables various powersaving modes in userspace and kernel.
27666 Contrary to @code{upower-service}, it is not a passive,
27667 monitoring tool, as it will apply custom settings each time a new power
27668 source is detected. More information can be found at
27669 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
27671 @deffn {Scheme Variable} tlp-service-type
27672 The service type for the TLP tool. The default settings are optimised
27673 for battery life on most systems, but you can tweak them to your heart's
27674 content by adding a valid @code{tlp-configuration}:
27676 (service tlp-service-type
27678 (cpu-scaling-governor-on-ac (list "performance"))
27679 (sched-powersave-on-bat? #t)))
27683 Each parameter definition is preceded by its type; for example,
27684 @samp{boolean foo} indicates that the @code{foo} parameter
27685 should be specified as a boolean. Types starting with
27686 @code{maybe-} denote parameters that won't show up in TLP config file
27687 when their value is @code{'disabled}.
27689 @c The following documentation was initially generated by
27690 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
27691 @c documentation is better, so we shouldn't hesitate to edit below as
27692 @c needed. However if the change you want to make to this documentation
27693 @c can be done in an automated way, it's probably easier to change
27694 @c (generate-documentation) than to make it below and have to deal with
27695 @c the churn as TLP updates.
27697 Available @code{tlp-configuration} fields are:
27699 @deftypevr {@code{tlp-configuration} parameter} package tlp
27704 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
27705 Set to true if you wish to enable TLP.
27707 Defaults to @samp{#t}.
27711 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
27712 Default mode when no power supply can be detected. Alternatives are AC
27715 Defaults to @samp{"AC"}.
27719 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
27720 Number of seconds Linux kernel has to wait after the disk goes idle,
27721 before syncing on AC.
27723 Defaults to @samp{0}.
27727 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
27728 Same as @code{disk-idle-ac} but on BAT mode.
27730 Defaults to @samp{2}.
27734 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
27735 Dirty pages flushing periodicity, expressed in seconds.
27737 Defaults to @samp{15}.
27741 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
27742 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
27744 Defaults to @samp{60}.
27748 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
27749 CPU frequency scaling governor on AC mode. With intel_pstate driver,
27750 alternatives are powersave and performance. With acpi-cpufreq driver,
27751 alternatives are ondemand, powersave, performance and conservative.
27753 Defaults to @samp{disabled}.
27757 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
27758 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
27760 Defaults to @samp{disabled}.
27764 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
27765 Set the min available frequency for the scaling governor on AC.
27767 Defaults to @samp{disabled}.
27771 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
27772 Set the max available frequency for the scaling governor on AC.
27774 Defaults to @samp{disabled}.
27778 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
27779 Set the min available frequency for the scaling governor on BAT.
27781 Defaults to @samp{disabled}.
27785 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
27786 Set the max available frequency for the scaling governor on BAT.
27788 Defaults to @samp{disabled}.
27792 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
27793 Limit the min P-state to control the power dissipation of the CPU, in AC
27794 mode. Values are stated as a percentage of the available performance.
27796 Defaults to @samp{disabled}.
27800 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
27801 Limit the max P-state to control the power dissipation of the CPU, in AC
27802 mode. Values are stated as a percentage of the available performance.
27804 Defaults to @samp{disabled}.
27808 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
27809 Same as @code{cpu-min-perf-on-ac} on BAT mode.
27811 Defaults to @samp{disabled}.
27815 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
27816 Same as @code{cpu-max-perf-on-ac} on BAT mode.
27818 Defaults to @samp{disabled}.
27822 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
27823 Enable CPU turbo boost feature on AC mode.
27825 Defaults to @samp{disabled}.
27829 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
27830 Same as @code{cpu-boost-on-ac?} on BAT mode.
27832 Defaults to @samp{disabled}.
27836 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
27837 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
27838 used under light load conditions.
27840 Defaults to @samp{#f}.
27844 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
27845 Same as @code{sched-powersave-on-ac?} but on BAT mode.
27847 Defaults to @samp{#t}.
27851 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
27852 Enable Linux kernel NMI watchdog.
27854 Defaults to @samp{#f}.
27858 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
27859 For Linux kernels with PHC patch applied, change CPU voltages. An
27860 example value would be @samp{"F:V F:V F:V F:V"}.
27862 Defaults to @samp{disabled}.
27866 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
27867 Set CPU performance versus energy saving policy on AC@. Alternatives are
27868 performance, normal, powersave.
27870 Defaults to @samp{"performance"}.
27874 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
27875 Same as @code{energy-perf-policy-ac} but on BAT mode.
27877 Defaults to @samp{"powersave"}.
27881 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
27886 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
27887 Hard disk advanced power management level.
27891 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
27892 Same as @code{disk-apm-bat} but on BAT mode.
27896 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
27897 Hard disk spin down timeout. One value has to be specified for each
27898 declared hard disk.
27900 Defaults to @samp{disabled}.
27904 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
27905 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
27907 Defaults to @samp{disabled}.
27911 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
27912 Select IO scheduler for disk devices. One value has to be specified for
27913 each declared hard disk. Example alternatives are cfq, deadline and
27916 Defaults to @samp{disabled}.
27920 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
27921 SATA aggressive link power management (ALPM) level. Alternatives are
27922 min_power, medium_power, max_performance.
27924 Defaults to @samp{"max_performance"}.
27928 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
27929 Same as @code{sata-linkpwr-ac} but on BAT mode.
27931 Defaults to @samp{"min_power"}.
27935 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
27936 Exclude specified SATA host devices for link power management.
27938 Defaults to @samp{disabled}.
27942 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
27943 Enable Runtime Power Management for AHCI controller and disks on AC
27946 Defaults to @samp{disabled}.
27950 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
27951 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
27953 Defaults to @samp{disabled}.
27957 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
27958 Seconds of inactivity before disk is suspended.
27960 Defaults to @samp{15}.
27964 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
27965 PCI Express Active State Power Management level. Alternatives are
27966 default, performance, powersave.
27968 Defaults to @samp{"performance"}.
27972 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
27973 Same as @code{pcie-aspm-ac} but on BAT mode.
27975 Defaults to @samp{"powersave"}.
27979 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
27980 Radeon graphics clock speed level. Alternatives are low, mid, high,
27983 Defaults to @samp{"high"}.
27987 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
27988 Same as @code{radeon-power-ac} but on BAT mode.
27990 Defaults to @samp{"low"}.
27994 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
27995 Radeon dynamic power management method (DPM). Alternatives are battery,
27998 Defaults to @samp{"performance"}.
28002 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
28003 Same as @code{radeon-dpm-state-ac} but on BAT mode.
28005 Defaults to @samp{"battery"}.
28009 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
28010 Radeon DPM performance level. Alternatives are auto, low, high.
28012 Defaults to @samp{"auto"}.
28016 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
28017 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
28019 Defaults to @samp{"auto"}.
28023 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
28024 Wifi power saving mode.
28026 Defaults to @samp{#f}.
28030 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
28031 Same as @code{wifi-power-ac?} but on BAT mode.
28033 Defaults to @samp{#t}.
28037 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
28038 Disable wake on LAN.
28040 Defaults to @samp{#t}.
28044 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
28045 Timeout duration in seconds before activating audio power saving on
28046 Intel HDA and AC97 devices. A value of 0 disables power saving.
28048 Defaults to @samp{0}.
28052 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
28053 Same as @code{sound-powersave-ac} but on BAT mode.
28055 Defaults to @samp{1}.
28059 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
28060 Disable controller in powersaving mode on Intel HDA devices.
28062 Defaults to @samp{#t}.
28066 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
28067 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
28068 powered on again by releasing (and reinserting) the eject lever or by
28069 pressing the disc eject button on newer models.
28071 Defaults to @samp{#f}.
28075 @deftypevr {@code{tlp-configuration} parameter} string bay-device
28076 Name of the optical drive device to power off.
28078 Defaults to @samp{"sr0"}.
28082 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
28083 Runtime Power Management for PCI(e) bus devices. Alternatives are on
28086 Defaults to @samp{"on"}.
28090 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
28091 Same as @code{runtime-pm-ac} but on BAT mode.
28093 Defaults to @samp{"auto"}.
28097 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
28098 Runtime Power Management for all PCI(e) bus devices, except blacklisted
28101 Defaults to @samp{#t}.
28105 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
28106 Exclude specified PCI(e) device addresses from Runtime Power Management.
28108 Defaults to @samp{disabled}.
28112 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
28113 Exclude PCI(e) devices assigned to the specified drivers from Runtime
28118 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
28119 Enable USB autosuspend feature.
28121 Defaults to @samp{#t}.
28125 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
28126 Exclude specified devices from USB autosuspend.
28128 Defaults to @samp{disabled}.
28132 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
28133 Exclude WWAN devices from USB autosuspend.
28135 Defaults to @samp{#t}.
28139 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
28140 Include specified devices into USB autosuspend, even if they are already
28141 excluded by the driver or via @code{usb-blacklist-wwan?}.
28143 Defaults to @samp{disabled}.
28147 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
28148 Enable USB autosuspend before shutdown.
28150 Defaults to @samp{disabled}.
28154 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
28155 Restore radio device state (bluetooth, wifi, wwan) from previous
28156 shutdown on system startup.
28158 Defaults to @samp{#f}.
28163 @cindex CPU frequency scaling with thermald
28164 @subsubheading Thermald daemon
28166 The @code{(gnu services pm)} module provides an interface to
28167 thermald, a CPU frequency scaling service which helps prevent overheating.
28169 @defvr {Scheme Variable} thermald-service-type
28170 This is the service type for
28171 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
28172 Thermal Daemon, which is responsible for controlling the thermal state
28173 of processors and preventing overheating.
28176 @deftp {Data Type} thermald-configuration
28177 Data type representing the configuration of @code{thermald-service-type}.
28180 @item @code{ignore-cpuid-check?} (default: @code{#f})
28181 Ignore cpuid check for supported CPU models.
28183 @item @code{thermald} (default: @var{thermald})
28184 Package object of thermald.
28189 @node Audio Services
28190 @subsection Audio Services
28192 The @code{(gnu services audio)} module provides a service to start MPD
28193 (the Music Player Daemon).
28196 @subsubheading Music Player Daemon
28198 The Music Player Daemon (MPD) is a service that can play music while
28199 being controlled from the local machine or over the network by a variety
28202 The following example shows how one might run @code{mpd} as user
28203 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
28206 (service mpd-service-type
28212 @defvr {Scheme Variable} mpd-service-type
28213 The service type for @command{mpd}
28216 @deftp {Data Type} mpd-configuration
28217 Data type representing the configuration of @command{mpd}.
28220 @item @code{user} (default: @code{"mpd"})
28221 The user to run mpd as.
28223 @item @code{music-dir} (default: @code{"~/Music"})
28224 The directory to scan for music files.
28226 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
28227 The directory to store playlists.
28229 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
28230 The location of the music database.
28232 @item @code{state-file} (default: @code{"~/.mpd/state"})
28233 The location of the file that stores current MPD's state.
28235 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
28236 The location of the sticker database.
28238 @item @code{port} (default: @code{"6600"})
28239 The port to run mpd on.
28241 @item @code{address} (default: @code{"any"})
28242 The address that mpd will bind to. To use a Unix domain socket,
28243 an absolute path can be specified here.
28245 @item @code{outputs} (default: @code{"(list (mpd-output))"})
28246 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
28251 @deftp {Data Type} mpd-output
28252 Data type representing an @command{mpd} audio output.
28255 @item @code{name} (default: @code{"MPD"})
28256 The name of the audio output.
28258 @item @code{type} (default: @code{"pulse"})
28259 The type of audio output.
28261 @item @code{enabled?} (default: @code{#t})
28262 Specifies whether this audio output is enabled when MPD is started. By
28263 default, all audio outputs are enabled. This is just the default
28264 setting when there is no state file; with a state file, the previous
28267 @item @code{tags?} (default: @code{#t})
28268 If set to @code{#f}, then MPD will not send tags to this output. This
28269 is only useful for output plugins that can receive tags, for example the
28270 @code{httpd} output plugin.
28272 @item @code{always-on?} (default: @code{#f})
28273 If set to @code{#t}, then MPD attempts to keep this audio output always
28274 open. This may be useful for streaming servers, when you don’t want to
28275 disconnect all listeners even when playback is accidentally stopped.
28277 @item @code{mixer-type}
28278 This field accepts a symbol that specifies which mixer should be used
28279 for this audio output: the @code{hardware} mixer, the @code{software}
28280 mixer, the @code{null} mixer (allows setting the volume, but with no
28281 effect; this can be used as a trick to implement an external mixer
28282 External Mixer) or no mixer (@code{none}).
28284 @item @code{extra-options} (default: @code{'()})
28285 An association list of option symbols to string values to be appended to
28286 the audio output configuration.
28291 The following example shows a configuration of @code{mpd} that provides
28292 an HTTP audio streaming output.
28295 (service mpd-service-type
28303 `((encoder . "vorbis")
28304 (port . "8080"))))))))
28308 @node Virtualization Services
28309 @subsection Virtualization Services
28311 The @code{(gnu services virtualization)} module provides services for
28312 the libvirt and virtlog daemons, as well as other virtualization-related
28315 @subsubheading Libvirt daemon
28317 @code{libvirtd} is the server side daemon component of the libvirt
28318 virtualization management system. This daemon runs on host servers
28319 and performs required management tasks for virtualized guests.
28321 @deffn {Scheme Variable} libvirt-service-type
28322 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
28323 Its value must be a @code{libvirt-configuration}.
28326 (service libvirt-service-type
28327 (libvirt-configuration
28328 (unix-sock-group "libvirt")
28329 (tls-port "16555")))
28333 @c Auto-generated with (generate-libvirt-documentation)
28334 Available @code{libvirt-configuration} fields are:
28336 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
28341 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
28342 Flag listening for secure TLS connections on the public TCP/IP port.
28343 You must set @code{listen} for this to have any effect.
28345 It is necessary to setup a CA and issue server certificates before using
28348 Defaults to @samp{#t}.
28352 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
28353 Listen for unencrypted TCP connections on the public TCP/IP port. You must
28354 set @code{listen} for this to have any effect.
28356 Using the TCP socket requires SASL authentication by default. Only SASL
28357 mechanisms which support data encryption are allowed. This is
28358 DIGEST_MD5 and GSSAPI (Kerberos5).
28360 Defaults to @samp{#f}.
28364 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
28365 Port for accepting secure TLS connections. This can be a port number,
28368 Defaults to @samp{"16514"}.
28372 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
28373 Port for accepting insecure TCP connections. This can be a port number,
28376 Defaults to @samp{"16509"}.
28380 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
28381 IP address or hostname used for client connections.
28383 Defaults to @samp{"0.0.0.0"}.
28387 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
28388 Flag toggling mDNS advertisement of the libvirt service.
28390 Alternatively can disable for all services on a host by stopping the
28393 Defaults to @samp{#f}.
28397 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
28398 Default mDNS advertisement name. This must be unique on the immediate
28401 Defaults to @samp{"Virtualization Host <hostname>"}.
28405 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
28406 UNIX domain socket group ownership. This can be used to allow a
28407 'trusted' set of users access to management capabilities without
28410 Defaults to @samp{"root"}.
28414 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
28415 UNIX socket permissions for the R/O socket. This is used for monitoring
28418 Defaults to @samp{"0777"}.
28422 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
28423 UNIX socket permissions for the R/W socket. Default allows only root.
28424 If PolicyKit is enabled on the socket, the default will change to allow
28425 everyone (eg, 0777)
28427 Defaults to @samp{"0770"}.
28431 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
28432 UNIX socket permissions for the admin socket. Default allows only owner
28433 (root), do not change it unless you are sure to whom you are exposing
28436 Defaults to @samp{"0777"}.
28440 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
28441 The directory in which sockets will be found/created.
28443 Defaults to @samp{"/var/run/libvirt"}.
28447 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
28448 Authentication scheme for UNIX read-only sockets. By default socket
28449 permissions allow anyone to connect
28451 Defaults to @samp{"polkit"}.
28455 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
28456 Authentication scheme for UNIX read-write sockets. By default socket
28457 permissions only allow root. If PolicyKit support was compiled into
28458 libvirt, the default will be to use 'polkit' auth.
28460 Defaults to @samp{"polkit"}.
28464 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
28465 Authentication scheme for TCP sockets. If you don't enable SASL, then
28466 all TCP traffic is cleartext. Don't do this outside of a dev/test
28469 Defaults to @samp{"sasl"}.
28473 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
28474 Authentication scheme for TLS sockets. TLS sockets already have
28475 encryption provided by the TLS layer, and limited authentication is done
28478 It is possible to make use of any SASL authentication mechanism as well,
28479 by using 'sasl' for this option
28481 Defaults to @samp{"none"}.
28485 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
28486 API access control scheme.
28488 By default an authenticated user is allowed access to all APIs. Access
28489 drivers can place restrictions on this.
28491 Defaults to @samp{()}.
28495 @deftypevr {@code{libvirt-configuration} parameter} string key-file
28496 Server key file path. If set to an empty string, then no private key is
28499 Defaults to @samp{""}.
28503 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
28504 Server key file path. If set to an empty string, then no certificate is
28507 Defaults to @samp{""}.
28511 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
28512 Server key file path. If set to an empty string, then no CA certificate
28515 Defaults to @samp{""}.
28519 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
28520 Certificate revocation list path. If set to an empty string, then no
28523 Defaults to @samp{""}.
28527 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
28528 Disable verification of our own server certificates.
28530 When libvirtd starts it performs some sanity checks against its own
28533 Defaults to @samp{#f}.
28537 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
28538 Disable verification of client certificates.
28540 Client certificate verification is the primary authentication mechanism.
28541 Any client which does not present a certificate signed by the CA will be
28544 Defaults to @samp{#f}.
28548 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
28549 Whitelist of allowed x509 Distinguished Name.
28551 Defaults to @samp{()}.
28555 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
28556 Whitelist of allowed SASL usernames. The format for username depends on
28557 the SASL authentication mechanism.
28559 Defaults to @samp{()}.
28563 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
28564 Override the compile time default TLS priority string. The default is
28565 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
28566 is desired for libvirt to deviate from the global default settings.
28568 Defaults to @samp{"NORMAL"}.
28572 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
28573 Maximum number of concurrent client connections to allow over all
28576 Defaults to @samp{5000}.
28580 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
28581 Maximum length of queue of connections waiting to be accepted by the
28582 daemon. Note, that some protocols supporting retransmission may obey
28583 this so that a later reattempt at connection succeeds.
28585 Defaults to @samp{1000}.
28589 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
28590 Maximum length of queue of accepted but not yet authenticated clients.
28591 Set this to zero to turn this feature off
28593 Defaults to @samp{20}.
28597 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
28598 Number of workers to start up initially.
28600 Defaults to @samp{5}.
28604 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
28605 Maximum number of worker threads.
28607 If the number of active clients exceeds @code{min-workers}, then more
28608 threads are spawned, up to max_workers limit. Typically you'd want
28609 max_workers to equal maximum number of clients allowed.
28611 Defaults to @samp{20}.
28615 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
28616 Number of priority workers. If all workers from above pool are stuck,
28617 some calls marked as high priority (notably domainDestroy) can be
28618 executed in this pool.
28620 Defaults to @samp{5}.
28624 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
28625 Total global limit on concurrent RPC calls.
28627 Defaults to @samp{20}.
28631 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
28632 Limit on concurrent requests from a single client connection. To avoid
28633 one client monopolizing the server this should be a small fraction of
28634 the global max_requests and max_workers parameter.
28636 Defaults to @samp{5}.
28640 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
28641 Same as @code{min-workers} but for the admin interface.
28643 Defaults to @samp{1}.
28647 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
28648 Same as @code{max-workers} but for the admin interface.
28650 Defaults to @samp{5}.
28654 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
28655 Same as @code{max-clients} but for the admin interface.
28657 Defaults to @samp{5}.
28661 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
28662 Same as @code{max-queued-clients} but for the admin interface.
28664 Defaults to @samp{5}.
28668 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
28669 Same as @code{max-client-requests} but for the admin interface.
28671 Defaults to @samp{5}.
28675 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
28676 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
28678 Defaults to @samp{3}.
28682 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
28685 A filter allows to select a different logging level for a given category
28686 of logs. The format for a filter is one of:
28697 where @code{name} is a string which is matched against the category
28698 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
28699 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
28700 name in the filter can be a substring of the full category name, in
28701 order to match multiple similar categories), the optional @samp{"+"}
28702 prefix tells libvirt to log stack trace for each message matching name,
28703 and @code{x} is the minimal level where matching messages should be
28721 Multiple filters can be defined in a single filters statement, they just
28722 need to be separated by spaces.
28724 Defaults to @samp{"3:remote 4:event"}.
28728 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
28731 An output is one of the places to save logging information. The format
28732 for an output can be:
28736 output goes to stderr
28738 @item x:syslog:name
28739 use syslog for the output and use the given name as the ident
28741 @item x:file:file_path
28742 output to a file, with the given filepath
28745 output to journald logging system
28749 In all case the x prefix is the minimal level, acting as a filter
28766 Multiple outputs can be defined, they just need to be separated by
28769 Defaults to @samp{"3:stderr"}.
28773 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
28774 Allows usage of the auditing subsystem to be altered
28778 0: disable all auditing
28781 1: enable auditing, only if enabled on host
28784 2: enable auditing, and exit if disabled on host.
28788 Defaults to @samp{1}.
28792 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
28793 Send audit messages via libvirt logging infrastructure.
28795 Defaults to @samp{#f}.
28799 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
28800 Host UUID@. UUID must not have all digits be the same.
28802 Defaults to @samp{""}.
28806 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
28807 Source to read host UUID.
28811 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
28814 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
28818 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
28821 Defaults to @samp{"smbios"}.
28825 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
28826 A keepalive message is sent to a client after @code{keepalive_interval}
28827 seconds of inactivity to check if the client is still responding. If
28828 set to -1, libvirtd will never send keepalive requests; however clients
28829 can still send them and the daemon will send responses.
28831 Defaults to @samp{5}.
28835 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
28836 Maximum number of keepalive messages that are allowed to be sent to the
28837 client without getting any response before the connection is considered
28840 In other words, the connection is automatically closed approximately
28841 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
28842 the last message received from the client. When @code{keepalive-count}
28843 is set to 0, connections will be automatically closed after
28844 @code{keepalive-interval} seconds of inactivity without sending any
28845 keepalive messages.
28847 Defaults to @samp{5}.
28851 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
28852 Same as above but for admin interface.
28854 Defaults to @samp{5}.
28858 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
28859 Same as above but for admin interface.
28861 Defaults to @samp{5}.
28865 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
28866 Timeout for Open vSwitch calls.
28868 The @code{ovs-vsctl} utility is used for the configuration and its
28869 timeout option is set by default to 5 seconds to avoid potential
28870 infinite waits blocking libvirt.
28872 Defaults to @samp{5}.
28876 @c %end of autogenerated docs
28878 @subsubheading Virtlog daemon
28879 The virtlogd service is a server side daemon component of libvirt that is
28880 used to manage logs from virtual machine consoles.
28882 This daemon is not used directly by libvirt client applications, rather it
28883 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
28884 standalone daemon, the main @code{libvirtd} daemon can be restarted without
28885 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
28886 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
28888 @deffn {Scheme Variable} virtlog-service-type
28889 This is the type of the virtlog daemon.
28890 Its value must be a @code{virtlog-configuration}.
28893 (service virtlog-service-type
28894 (virtlog-configuration
28895 (max-clients 1000)))
28899 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
28900 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
28902 Defaults to @samp{3}.
28906 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
28909 A filter allows to select a different logging level for a given category
28910 of logs The format for a filter is one of:
28921 where @code{name} is a string which is matched against the category
28922 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
28923 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
28924 be a substring of the full category name, in order to match multiple
28925 similar categories), the optional "+" prefix tells libvirt to log stack
28926 trace for each message matching name, and @code{x} is the minimal level
28927 where matching messages should be logged:
28944 Multiple filters can be defined in a single filters statement, they just
28945 need to be separated by spaces.
28947 Defaults to @samp{"3:remote 4:event"}.
28951 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
28954 An output is one of the places to save logging information The format
28955 for an output can be:
28959 output goes to stderr
28961 @item x:syslog:name
28962 use syslog for the output and use the given name as the ident
28964 @item x:file:file_path
28965 output to a file, with the given filepath
28968 output to journald logging system
28972 In all case the x prefix is the minimal level, acting as a filter
28989 Multiple outputs can be defined, they just need to be separated by
28992 Defaults to @samp{"3:stderr"}.
28996 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
28997 Maximum number of concurrent client connections to allow over all
29000 Defaults to @samp{1024}.
29004 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
29005 Maximum file size before rolling over.
29007 Defaults to @samp{2MB}
29011 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
29012 Maximum number of backup files to keep.
29014 Defaults to @samp{3}
29018 @anchor{transparent-emulation-qemu}
29019 @subsubheading Transparent Emulation with QEMU
29022 @cindex @code{binfmt_misc}
29023 @code{qemu-binfmt-service-type} provides support for transparent
29024 emulation of program binaries built for different architectures---e.g.,
29025 it allows you to transparently execute an ARMv7 program on an x86_64
29026 machine. It achieves this by combining the @uref{https://www.qemu.org,
29027 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
29028 This feature only allows you to emulate GNU/Linux on a different
29029 architecture, but see below for GNU/Hurd support.
29031 @defvr {Scheme Variable} qemu-binfmt-service-type
29032 This is the type of the QEMU/binfmt service for transparent emulation.
29033 Its value must be a @code{qemu-binfmt-configuration} object, which
29034 specifies the QEMU package to use as well as the architecture we want to
29038 (service qemu-binfmt-service-type
29039 (qemu-binfmt-configuration
29040 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
29043 In this example, we enable transparent emulation for the ARM and aarch64
29044 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
29045 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
29046 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
29049 @deftp {Data Type} qemu-binfmt-configuration
29050 This is the configuration for the @code{qemu-binfmt} service.
29053 @item @code{platforms} (default: @code{'()})
29054 The list of emulated QEMU platforms. Each item must be a @dfn{platform
29055 object} as returned by @code{lookup-qemu-platforms} (see below).
29057 For example, let's suppose you're on an x86_64 machine and you have this
29061 (service qemu-binfmt-service-type
29062 (qemu-binfmt-configuration
29063 (platforms (lookup-qemu-platforms "arm"))))
29069 guix build -s armhf-linux inkscape
29073 and it will build Inkscape for ARMv7 @emph{as if it were a native
29074 build}, transparently using QEMU to emulate the ARMv7 CPU@. Pretty handy
29075 if you'd like to test a package build for an architecture you don't have
29078 @item @code{qemu} (default: @code{qemu})
29079 The QEMU package to use.
29083 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
29084 Return the list of QEMU platform objects corresponding to
29085 @var{platforms}@dots{}. @var{platforms} must be a list of strings
29086 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
29087 @code{"mips64el"}, and so on.
29090 @deffn {Scheme Procedure} qemu-platform? @var{obj}
29091 Return true if @var{obj} is a platform object.
29094 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
29095 Return the name of @var{platform}---a string such as @code{"arm"}.
29099 @subsubheading The Hurd in a Virtual Machine
29101 @cindex @code{hurd}
29105 Service @code{hurd-vm} provides support for running GNU/Hurd in a
29106 virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
29107 to be used on GNU/Linux and the given GNU/Hurd operating system
29108 configuration is cross-compiled. The virtual machine is a Shepherd
29109 service that can be referred to by the names @code{hurd-vm} and
29110 @code{childhurd} and be controlled with commands such as:
29114 herd stop childhurd
29117 When the service is running, you can view its console by connecting to
29118 it with a VNC client, for example with:
29121 guix environment --ad-hoc tigervnc-client -- \
29122 vncviewer localhost:5900
29125 The default configuration (see @code{hurd-vm-configuration} below)
29126 spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
29127 (the virtual machine emulator) redirects to port 10222 on the host.
29128 Thus, you can connect over SSH to the childhurd with:
29131 ssh root@@localhost -p 10022
29134 The childhurd is volatile and stateless: it starts with a fresh root
29135 file system every time you restart it. By default though, all the files
29136 under @file{/etc/childhurd} on the host are copied as is to the root
29137 file system of the childhurd when it boots. This allows you to
29138 initialize ``secrets'' inside the VM: SSH host keys, authorized
29139 substitute keys, and so on---see the explanation of @code{secret-root}
29142 @defvr {Scheme Variable} hurd-vm-service-type
29143 This is the type of the Hurd in a Virtual Machine service. Its value
29144 must be a @code{hurd-vm-configuration} object, which specifies the
29145 operating system (@pxref{operating-system Reference}) and the disk size
29146 for the Hurd Virtual Machine, the QEMU package to use as well as the
29147 options for running it.
29152 (service hurd-vm-service-type
29153 (hurd-vm-configuration
29154 (disk-size (* 5000 (expt 2 20))) ;5G
29155 (memory-size 1024))) ;1024MiB
29158 would create a disk image big enough to build GNU@tie{}Hello, with some
29162 @deftp {Data Type} hurd-vm-configuration
29163 The data type representing the configuration for
29164 @code{hurd-vm-service-type}.
29167 @item @code{os} (default: @var{%hurd-vm-operating-system})
29168 The operating system to instantiate. This default is bare-bones with a
29169 permissive OpenSSH secure shell daemon listening on port 2222
29170 (@pxref{Networking Services, @code{openssh-service-type}}).
29172 @item @code{qemu} (default: @code{qemu-minimal})
29173 The QEMU package to use.
29175 @item @code{image} (default: @var{hurd-vm-disk-image})
29176 The procedure used to build the disk-image built from this
29179 @item @code{disk-size} (default: @code{'guess})
29180 The size of the disk image.
29182 @item @code{memory-size} (default: @code{512})
29183 The memory size of the Virtual Machine in mebibytes.
29185 @item @code{options} (default: @code{'("--snapshot")})
29186 The extra options for running QEMU.
29188 @item @code{id} (default: @code{#f})
29189 If set, a non-zero positive integer used to parameterize Childhurd
29190 instances. It is appended to the service's name,
29191 e.g. @code{childhurd1}.
29193 @item @code{net-options} (default: @var{hurd-vm-net-options})
29194 The procedure used to produce the list of QEMU networking options.
29196 By default, it produces
29199 '("--device" "rtl8139,netdev=net0"
29200 "--netdev" (string-append
29202 "hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004,"
29203 "hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222,"
29204 "hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900"))
29207 with forwarded ports:
29210 @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
29211 @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
29212 @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
29215 @item @code{secret-root} (default: @file{/etc/childhurd})
29216 The root directory with out-of-band secrets to be installed into the
29217 childhurd once it runs. Childhurds are volatile which means that on
29218 every startup, secrets such as the SSH host keys and Guix signing key
29221 If the @file{/etc/childhurd} directory does not exist, the
29222 @code{secret-service} running in the Childhurd will be sent an empty
29225 By default, the service automatically populates @file{/etc/childhurd}
29226 with the following non-volatile secrets, unless they already exist:
29229 /etc/childhurd/etc/guix/acl
29230 /etc/childhurd/etc/guix/signing-key.pub
29231 /etc/childhurd/etc/guix/signing-key.sec
29232 /etc/childhurd/etc/ssh/ssh_host_ed25519_key
29233 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
29234 /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
29235 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
29238 These files are automatically sent to the guest Hurd VM when it boots,
29239 including permissions.
29241 @cindex childhurd, offloading
29242 @cindex Hurd, offloading
29243 Having these files in place means that only a couple of things are
29244 missing to allow the host to offload @code{i586-gnu} builds to the
29249 Authorizing the childhurd's key on the host so that the host accepts
29250 build results coming from the childhurd, which can be done like so:
29253 guix archive --authorize < \
29254 /etc/childhurd/etc/guix/signing-key.pub
29258 Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
29262 We're working towards making that happen automatically---get in touch
29263 with us at @email{guix-devel@@gnu.org} to discuss it!
29267 Note that by default the VM image is volatile, i.e., once stopped the
29268 contents are lost. If you want a stateful image instead, override the
29269 configuration's @code{image} and @code{options} without
29270 the @code{--snapshot} flag using something along these lines:
29273 (service hurd-vm-service-type
29274 (hurd-vm-configuration
29275 (image (const "/out/of/store/writable/hurd.img"))
29279 @subsubheading Ganeti
29284 This service is considered experimental. Configuration options may be changed
29285 in a backwards-incompatible manner, and not all features have been thorougly
29286 tested. Users of this service are encouraged to share their experience at
29287 @email{guix-devel@@gnu.org}.
29290 Ganeti is a virtual machine management system. It is designed to keep virtual
29291 machines running on a cluster of servers even in the event of hardware failures,
29292 and to make maintenance and recovery tasks easy. It consists of multiple
29293 services which are described later in this section. In addition to the Ganeti
29294 service, you will need the OpenSSH service (@pxref{Networking Services,
29295 @code{openssh-service-type}}), and update the @file{/etc/hosts} file
29296 (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
29297 and address (or use a DNS server).
29299 All nodes participating in a Ganeti cluster should have the same Ganeti and
29300 @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
29301 cluster node that supports multiple storage backends, and installs the
29302 @code{debootstrap} and @code{guix} @dfn{OS providers}:
29305 (use-package-modules virtualization)
29306 (use-service-modules base ganeti networking ssh)
29309 (host-name "node1")
29310 (hosts-file (plain-file "hosts" (format #f "
29311 127.0.0.1 localhost
29314 192.168.1.200 ganeti.example.com
29315 192.168.1.201 node1.example.com node1
29316 192.168.1.202 node2.example.com node2
29319 ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
29320 ;; in order to use the "plain", "drbd" and "rbd" storage backends.
29321 (packages (append (map specification->package
29322 '("qemu" "lvm2" "drbd-utils" "ceph"
29323 ;; Add the debootstrap and guix OS providers.
29324 "ganeti-instance-guix" "ganeti-instance-debootstrap"))
29327 (append (list (static-networking-service "eth0" "192.168.1.201"
29328 #:netmask "255.255.255.0"
29329 #:gateway "192.168.1.254"
29330 #:name-servers '("192.168.1.252"
29333 ;; Ganeti uses SSH to communicate between nodes.
29334 (service openssh-service-type
29335 (openssh-configuration
29336 (permit-root-login 'without-password)))
29338 (service ganeti-service-type
29339 (ganeti-configuration
29340 ;; This list specifies allowed file system paths
29341 ;; for storing virtual machine images.
29342 (file-storage-paths '("/srv/ganeti/file-storage"))
29343 ;; This variable configures a single "variant" for
29344 ;; both Debootstrap and Guix that works with KVM.
29345 (os %default-ganeti-os))))
29349 Users are advised to read the
29350 @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
29351 administrators guide} to learn about the various cluster options and
29352 day-to-day operations. There is also a
29353 @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
29354 describing how to configure and initialize a small cluster.
29356 @defvr {Scheme Variable} ganeti-service-type
29357 This is a service type that includes all the various services that Ganeti
29360 Its value is a @code{ganeti-configuration} object that defines the package
29361 to use for CLI operations, as well as configuration for the various daemons.
29362 Allowed file storage paths and available guest operating systems are also
29363 configured through this data type.
29366 @deftp {Data Type} ganeti-configuration
29367 The @code{ganeti} service takes the following configuration options:
29370 @item @code{ganeti} (default: @code{ganeti})
29371 The @code{ganeti} package to use. It will be installed to the system profile
29372 and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
29373 that the value specified here does not affect the other services as each refer
29374 to a specific @code{ganeti} package (see below).
29376 @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
29377 @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
29378 @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
29379 @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
29380 @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
29381 @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
29382 @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
29383 @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
29384 @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
29385 @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
29387 These options control the various daemons and cron jobs that are distributed
29388 with Ganeti. The possible values for these are described in detail below.
29389 To override a setting, you must use the configuration type for that service:
29392 (service ganeti-service-type
29393 (ganeti-configuration
29394 (rapi-configuration
29395 (ganeti-rapi-configuration
29396 (interface "eth1"))))
29397 (watcher-configuration
29398 (ganeti-watcher-configuration
29399 (rapi-ip "10.0.0.1"))))
29402 @item @code{file-storage-paths} (default: @code{'()})
29403 List of allowed directories for file storage backend.
29405 @item @code{os} (default: @code{%default-ganeti-os})
29406 List of @code{<ganeti-os>} records.
29409 In essence @code{ganeti-service-type} is shorthand for declaring each service
29413 (service ganeti-noded-service-type)
29414 (service ganeti-confd-service-type)
29415 (service ganeti-wconfd-service-type)
29416 (service ganeti-luxid-service-type)
29417 (service ganeti-kvmd-service-type)
29418 (service ganeti-mond-service-type)
29419 (service ganeti-metad-service-type)
29420 (service ganeti-watcher-service-type)
29421 (service ganeti-cleaner-service-type)
29424 Plus a service extension for @code{etc-service-type} that configures the file
29425 storage backend and OS variants.
29429 @deftp {Data Type} ganeti-os
29430 This data type is suitable for passing to the @code{os} parameter of
29431 @code{ganeti-configuration}. It takes the following parameters:
29435 The name for this OS provider. It is only used to specify where the
29436 configuration ends up. Setting it to ``debootstrap'' will create
29437 @file{/etc/ganeti/instance-debootstrap}.
29439 @item @code{extension}
29440 The file extension for variants of this OS type. For example
29441 @file{.conf} or @file{.scm}.
29443 @item @code{variants} (default: @code{'()})
29444 List of @code{ganeti-os-variant} objects for this OS.
29449 @deftp {Data Type} ganeti-os-variant
29450 This is the data type for a Ganeti OS variant. It takes the following
29455 The name of this variant.
29457 @item @code{configuration}
29458 A configuration file for this variant.
29462 @defvr {Scheme Variable} %default-debootstrap-hooks
29463 This variable contains hooks to configure networking and the GRUB bootloader.
29466 @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
29467 This variable contains a list of packages suitable for a fully-virtualized guest.
29470 @deftp {Data Type} debootstrap-configuration
29472 This data type creates configuration files suitable for the debootstrap OS provider.
29475 @item @code{hooks} (default: @code{%default-debootstrap-hooks})
29476 When not @code{#f}, this must be a G-expression that specifies a directory with
29477 scripts that will run when the OS is installed. It can also be a list of
29478 @code{(name . file-like)} pairs. For example:
29481 `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
29484 That will create a directory with one executable named @code{99-hello-world}
29485 and run it every time this variant is installed. If set to @code{#f}, hooks
29486 in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
29487 @item @code{proxy} (default: @code{#f})
29488 Optional HTTP proxy to use.
29489 @item @code{mirror} (default: @code{#f})
29490 The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
29491 The default varies depending on the distribution.
29492 @item @code{arch} (default: @code{#f})
29493 The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
29494 on an AArch64 host. Default is to use the current system architecture.
29495 @item @code{suite} (default: @code{"stable"})
29496 When set, this must be a Debian distribution ``suite'' such as @code{buster}
29497 or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
29498 @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
29499 List of extra packages that will get installed by dpkg in addition
29500 to the minimal system.
29501 @item @code{components} (default: @code{#f})
29502 When set, must be a list of Debian repository ``components''. For example
29503 @code{'("main" "contrib")}.
29504 @item @code{generate-cache?} (default: @code{#t})
29505 Whether to automatically cache the generated debootstrap archive.
29506 @item @code{clean-cache} (default: @code{14})
29507 Discard the cache after this amount of days. Use @code{#f} to never
29509 @item @code{partition-style} (default: @code{'msdos})
29510 The type of partition to create. When set, it must be one of
29511 @code{'msdos}, @code{'none} or a string.
29512 @item @code{partition-alignment} (default: @code{2048})
29513 Alignment of the partition in sectors.
29517 @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
29518 This is a helper procedure that creates a @code{ganeti-os-variant} record. It
29519 takes two parameters: a name and a @code{debootstrap-configuration} object.
29522 @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
29523 This is a helper procedure that creates a @code{ganeti-os} record. It takes
29524 a list of variants created with @code{debootstrap-variant}.
29527 @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
29528 This is a helper procedure that creates a @code{ganeti-os-variant} record for
29529 use with the Guix OS provider. It takes a name and a G-expression that returns
29530 a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
29531 Guix System configuration.
29534 @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
29535 This is a helper procedure that creates a @code{ganeti-os} record. It
29536 takes a list of variants produced by @code{guix-variant}.
29539 @defvr {Scheme Variable} %default-debootstrap-variants
29540 This is a convenience variable to make the debootstrap provider work
29541 ``out of the box'' without users having to declare variants manually. It
29542 contains a single debootstrap variant with the default configuration:
29545 (list (debootstrap-variant
29547 (debootstrap-configuration)))
29551 @defvr {Scheme Variable} %default-guix-variants
29552 This is a convenience variable to make the Guix OS provider work without
29553 additional configuration. It creates a virtual machine that has an SSH
29554 server, a serial console, and authorizes the Ganeti hosts SSH keys.
29557 (list (guix-variant
29559 (file-append ganeti-instance-guix
29560 "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
29564 Users can implement support for OS providers unbeknownst to Guix by extending
29565 the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
29571 (extension ".conf")
29573 (list (ganeti-os-variant
29575 (configuration (plain-file "bar" "this is fine"))))))
29578 That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
29579 to a file in the store with contents @code{this is fine}. It also creates
29580 @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
29582 Obviously this may not work for all OS providers out there. If you find the
29583 interface limiting, please reach out to @email{guix-devel@@gnu.org}.
29585 The rest of this section documents the various services that are included by
29586 @code{ganeti-service-type}.
29588 @defvr {Scheme Variable} ganeti-noded-service-type
29589 @command{ganeti-noded} is the daemon responsible for node-specific functions
29590 within the Ganeti system. The value of this service must be a
29591 @code{ganeti-noded-configuration} object.
29594 @deftp {Data Type} ganeti-noded-configuration
29595 This is the configuration for the @code{ganeti-noded} service.
29598 @item @code{ganeti} (default: @code{ganeti})
29599 The @code{ganeti} package to use for this service.
29601 @item @code{port} (default: @code{1811})
29602 The TCP port on which the node daemon listens for network requests.
29604 @item @code{address} (default: @code{"0.0.0.0"})
29605 The network address that the daemon will bind to. The default address means
29606 bind to all available addresses.
29608 @item @code{interface} (default: @code{#f})
29609 When this is set, it must be a specific network interface (e.g.@: @code{eth0})
29610 that the daemon will bind to.
29612 @item @code{max-clients} (default: @code{20})
29613 This sets a limit on the maximum number of simultaneous client connections
29614 that the daemon will handle. Connections above this count are accepted, but
29615 no responses will be sent until enough connections have closed.
29617 @item @code{ssl?} (default: @code{#t})
29618 Whether to use SSL/TLS to encrypt network communications. The certificate
29619 is automatically provisioned by the cluster and can be rotated with
29620 @command{gnt-cluster renew-crypto}.
29622 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
29623 This can be used to provide a specific encryption key for TLS communications.
29625 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
29626 This can be used to provide a specific certificate for TLS communications.
29628 @item @code{debug?} (default: @code{#f})
29629 When true, the daemon performs additional logging for debugging purposes.
29630 Note that this will leak encryption details to the log files, use with caution.
29635 @defvr {Scheme Variable} ganeti-confd-service-type
29636 @command{ganeti-confd} answers queries related to the configuration of a
29637 Ganeti cluster. The purpose of this daemon is to have a highly available
29638 and fast way to query cluster configuration values. It is automatically
29639 active on all @dfn{master candidates}. The value of this service must be a
29640 @code{ganeti-confd-configuration} object.
29644 @deftp {Data Type} ganeti-confd-configuration
29645 This is the configuration for the @code{ganeti-confd} service.
29648 @item @code{ganeti} (default: @code{ganeti})
29649 The @code{ganeti} package to use for this service.
29651 @item @code{port} (default: @code{1814})
29652 The UDP port on which to listen for network requests.
29654 @item @code{address} (default: @code{"0.0.0.0"})
29655 Network address that the daemon will bind to.
29657 @item @code{debug?} (default: @code{#f})
29658 When true, the daemon performs additional logging for debugging purposes.
29663 @defvr {Scheme Variable} ganeti-wconfd-service-type
29664 @command{ganeti-wconfd} is the daemon that has authoritative knowledge
29665 about the cluster configuration and is the only entity that can accept
29666 changes to it. All jobs that need to modify the configuration will do so
29667 by sending appropriate requests to this daemon. It only runs on the
29668 @dfn{master node} and will automatically disable itself on other nodes.
29670 The value of this service must be a
29671 @code{ganeti-wconfd-configuration} object.
29674 @deftp {Data Type} ganeti-wconfd-configuration
29675 This is the configuration for the @code{ganeti-wconfd} service.
29678 @item @code{ganeti} (default: @code{ganeti})
29679 The @code{ganeti} package to use for this service.
29681 @item @code{no-voting?} (default: @code{#f})
29682 The daemon will refuse to start if the majority of cluster nodes does not
29683 agree that it is running on the master node. Set to @code{#t} to start
29684 even if a quorum can not be reached (dangerous, use with caution).
29686 @item @code{debug?} (default: @code{#f})
29687 When true, the daemon performs additional logging for debugging purposes.
29692 @defvr {Scheme Variable} ganeti-luxid-service-type
29693 @command{ganeti-luxid} is a daemon used to answer queries related to the
29694 configuration and the current live state of a Ganeti cluster. Additionally,
29695 it is the authoritative daemon for the Ganeti job queue. Jobs can be
29696 submitted via this daemon and it schedules and starts them.
29698 It takes a @code{ganeti-luxid-configuration} object.
29701 @deftp {Data Type} ganeti-luxid-configuration
29702 This is the configuration for the @code{ganeti-wconfd} service.
29705 @item @code{ganeti} (default: @code{ganeti})
29706 The @code{ganeti} package to use for this service.
29708 @item @code{no-voting?} (default: @code{#f})
29709 The daemon will refuse to start if it cannot verify that the majority of
29710 cluster nodes believes that it is running on the master node. Set to
29711 @code{#t} to ignore such checks and start anyway (this can be dangerous).
29713 @item @code{debug?} (default: @code{#f})
29714 When true, the daemon performs additional logging for debugging purposes.
29719 @defvr {Scheme Variable} ganeti-rapi-service-type
29720 @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
29721 the master node and can be used to perform cluster actions programmatically
29722 via a JSON-based RPC protocol.
29724 Most query operations are allowed without authentication (unless
29725 @var{require-authentication?} is set), whereas write operations require
29726 explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
29727 the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
29728 API documentation} for more information.
29730 The value of this service must be a @code{ganeti-rapi-configuration} object.
29733 @deftp {Data Type} ganeti-rapi-configuration
29734 This is the configuration for the @code{ganeti-rapi} service.
29737 @item @code{ganeti} (default: @code{ganeti})
29738 The @code{ganeti} package to use for this service.
29740 @item @code{require-authentication?} (default: @code{#f})
29741 Whether to require authentication even for read-only operations.
29743 @item @code{port} (default: @code{5080})
29744 The TCP port on which to listen to API requests.
29746 @item @code{address} (default: @code{"0.0.0.0"})
29747 The network address that the service will bind to. By default it listens
29748 on all configured addresses.
29750 @item @code{interface} (default: @code{#f})
29751 When set, it must specify a specific network interface such as @code{eth0}
29752 that the daemon will bind to.
29754 @item @code{max-clients} (default: @code{20})
29755 The maximum number of simultaneous client requests to handle. Further
29756 connections are allowed, but no responses are sent until enough connections
29759 @item @code{ssl?} (default: @code{#t})
29760 Whether to use SSL/TLS encryption on the RAPI port.
29762 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
29763 This can be used to provide a specific encryption key for TLS communications.
29765 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
29766 This can be used to provide a specific certificate for TLS communications.
29768 @item @code{debug?} (default: @code{#f})
29769 When true, the daemon performs additional logging for debugging purposes.
29770 Note that this will leak encryption details to the log files, use with caution.
29775 @defvr {Scheme Variable} ganeti-kvmd-service-type
29776 @command{ganeti-kvmd} is responsible for determining whether a given KVM
29777 instance was shut down by an administrator or a user. Normally Ganeti will
29778 restart an instance that was not stopped through Ganeti itself. If the
29779 cluster option @code{user_shutdown} is true, this daemon monitors the
29780 @code{QMP} socket provided by QEMU and listens for shutdown events, and
29781 marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
29782 it shuts down gracefully by itself.
29784 It takes a @code{ganeti-kvmd-configuration} object.
29787 @deftp {Data Type} ganeti-kvmd-configuration
29790 @item @code{ganeti} (default: @code{ganeti})
29791 The @code{ganeti} package to use for this service.
29793 @item @code{debug?} (default: @code{#f})
29794 When true, the daemon performs additional logging for debugging purposes.
29799 @defvr {Scheme Variable} ganeti-mond-service-type
29800 @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
29801 functionality. It is responsible for running data collectors and publish the
29802 collected information through a HTTP interface.
29804 It takes a @code{ganeti-mond-configuration} object.
29807 @deftp {Data Type} ganeti-mond-configuration
29810 @item @code{ganeti} (default: @code{ganeti})
29811 The @code{ganeti} package to use for this service.
29813 @item @code{port} (default: @code{1815})
29814 The port on which the daemon will listen.
29816 @item @code{address} (default: @code{"0.0.0.0"})
29817 The network address that the daemon will bind to. By default it binds to all
29818 available interfaces.
29820 @item @code{debug?} (default: @code{#f})
29821 When true, the daemon performs additional logging for debugging purposes.
29826 @defvr {Scheme Variable} ganeti-metad-service-type
29827 @command{ganeti-metad} is an optional daemon that can be used to provide
29828 information about the cluster to instances or OS install scripts.
29830 It takes a @code{ganeti-metad-configuration} object.
29833 @deftp {Data Type} ganeti-metad-configuration
29836 @item @code{ganeti} (default: @code{ganeti})
29837 The @code{ganeti} package to use for this service.
29839 @item @code{port} (default: @code{80})
29840 The port on which the daemon will listen.
29842 @item @code{address} (default: @code{#f})
29843 If set, the daemon will bind to this address only. If left unset, the behavior
29844 depends on the cluster configuration.
29846 @item @code{debug?} (default: @code{#f})
29847 When true, the daemon performs additional logging for debugging purposes.
29852 @defvr {Scheme Variable} ganeti-watcher-service-type
29853 @command{ganeti-watcher} is a script designed to run periodically and ensure
29854 the health of a cluster. It will automatically restart instances that have
29855 stopped without Ganeti's consent, and repairs DRBD links in case a node has
29856 rebooted. It also archives old cluster jobs and restarts Ganeti daemons
29857 that are not running. If the cluster parameter @code{ensure_node_health}
29858 is set, the watcher will also shutdown instances and DRBD devices if the
29859 node it is running on is declared offline by known master candidates.
29861 It can be paused on all nodes with @command{gnt-cluster watcher pause}.
29863 The service takes a @code{ganeti-watcher-configuration} object.
29866 @deftp {Data Type} ganeti-watcher-configuration
29869 @item @code{ganeti} (default: @code{ganeti})
29870 The @code{ganeti} package to use for this service.
29872 @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
29873 How often to run the script. The default is every five minutes.
29875 @item @code{rapi-ip} (default: @code{#f})
29876 This option needs to be specified only if the RAPI daemon is configured to use
29877 a particular interface or address. By default the cluster address is used.
29879 @item @code{job-age} (default: @code{(* 6 3600)})
29880 Archive cluster jobs older than this age, specified in seconds. The default
29881 is 6 hours. This keeps @command{gnt-job list} manageable.
29883 @item @code{verify-disks?} (default: @code{#t})
29884 If this is @code{#f}, the watcher will not try to repair broken DRBD links
29885 automatically. Administrators will need to use @command{gnt-cluster verify-disks}
29888 @item @code{debug?} (default: @code{#f})
29889 When @code{#t}, the script performs additional logging for debugging purposes.
29894 @defvr {Scheme Variable} ganeti-cleaner-service-type
29895 @command{ganeti-cleaner} is a script designed to run periodically and remove
29896 old files from the cluster. This service type controls two @dfn{cron jobs}:
29897 one intended for the master node that permanently purges old cluster jobs,
29898 and one intended for every node that removes expired X509 certificates, keys,
29899 and outdated @command{ganeti-watcher} information. Like all Ganeti services,
29900 it is safe to include even on non-master nodes as it will disable itself as
29903 It takes a @code{ganeti-cleaner-configuration} object.
29906 @deftp {Data Type} ganeti-cleaner-configuration
29909 @item @code{ganeti} (default: @code{ganeti})
29910 The @code{ganeti} package to use for the @command{gnt-cleaner} command.
29912 @item @code{master-schedule} (default: @code{"45 1 * * *"})
29913 How often to run the master cleaning job. The default is once per day, at
29916 @item @code{node-schedule} (default: @code{"45 2 * * *"})
29917 How often to run the node cleaning job. The default is once per day, at
29923 @node Version Control Services
29924 @subsection Version Control Services
29926 The @code{(gnu services version-control)} module provides a service to
29927 allow remote access to local Git repositories. There are three options:
29928 the @code{git-daemon-service}, which provides access to repositories via
29929 the @code{git://} unsecured TCP-based protocol, extending the
29930 @code{nginx} web server to proxy some requests to
29931 @code{git-http-backend}, or providing a web interface with
29932 @code{cgit-service-type}.
29934 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
29936 Return a service that runs @command{git daemon}, a simple TCP server to
29937 expose repositories over the Git protocol for anonymous access.
29939 The optional @var{config} argument should be a
29940 @code{<git-daemon-configuration>} object, by default it allows read-only
29941 access to exported@footnote{By creating the magic file
29942 @file{git-daemon-export-ok} in the repository directory.} repositories under
29947 @deftp {Data Type} git-daemon-configuration
29948 Data type representing the configuration for @code{git-daemon-service}.
29951 @item @code{package} (default: @code{git})
29952 Package object of the Git distributed version control system.
29954 @item @code{export-all?} (default: @code{#f})
29955 Whether to allow access for all Git repositories, even if they do not
29956 have the @file{git-daemon-export-ok} file.
29958 @item @code{base-path} (default: @file{/srv/git})
29959 Whether to remap all the path requests as relative to the given path.
29960 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
29961 @samp{example.com}, then if you later try to pull
29962 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
29963 path as @file{/srv/git/hello.git}.
29965 @item @code{user-path} (default: @code{#f})
29966 Whether to allow @code{~user} notation to be used in requests. When
29967 specified with empty string, requests to
29968 @indicateurl{git://host/~alice/foo} is taken as a request to access
29969 @code{foo} repository in the home directory of user @code{alice}. If
29970 @code{(user-path "@var{path}")} is specified, the same request is taken
29971 as a request to access @file{@var{path}/foo} repository in the home
29972 directory of user @code{alice}.
29974 @item @code{listen} (default: @code{'()})
29975 Whether to listen on specific IP addresses or hostnames, defaults to
29978 @item @code{port} (default: @code{#f})
29979 Whether to listen on an alternative port, which defaults to 9418.
29981 @item @code{whitelist} (default: @code{'()})
29982 If not empty, only allow access to this list of directories.
29984 @item @code{extra-options} (default: @code{'()})
29985 Extra options will be passed to @command{git daemon}, please run
29986 @command{man git-daemon} for more information.
29991 The @code{git://} protocol lacks authentication. When you pull from a
29992 repository fetched via @code{git://}, you don't know whether the data you
29993 receive was modified or is even coming from the specified host, and your
29994 connection is subject to eavesdropping. It's better to use an authenticated
29995 and encrypted transport, such as @code{https}. Although Git allows you
29996 to serve repositories using unsophisticated file-based web servers,
29997 there is a faster protocol implemented by the @code{git-http-backend}
29998 program. This program is the back-end of a proper Git web service. It
29999 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
30000 on running the necessary @code{fcgiwrap} daemon.
30002 Guix has a separate configuration data type for serving Git repositories
30005 @deftp {Data Type} git-http-configuration
30006 Data type representing the configuration for a future
30007 @code{git-http-service-type}; can currently be used to configure Nginx
30008 through @code{git-http-nginx-location-configuration}.
30011 @item @code{package} (default: @var{git})
30012 Package object of the Git distributed version control system.
30014 @item @code{git-root} (default: @file{/srv/git})
30015 Directory containing the Git repositories to expose to the world.
30017 @item @code{export-all?} (default: @code{#f})
30018 Whether to expose access for all Git repositories in @var{git-root},
30019 even if they do not have the @file{git-daemon-export-ok} file.
30021 @item @code{uri-path} (default: @samp{/git/})
30022 Path prefix for Git access. With the default @samp{/git/} prefix, this
30023 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
30024 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
30025 with this prefix are not passed on to this Git instance.
30027 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
30028 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
30033 There is no @code{git-http-service-type}, currently; instead you can
30034 create an @code{nginx-location-configuration} from a
30035 @code{git-http-configuration} and then add that location to a web
30038 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
30039 [config=(git-http-configuration)]
30040 Compute an @code{nginx-location-configuration} that corresponds to the
30041 given Git http configuration. An example nginx service definition to
30042 serve the default @file{/srv/git} over HTTPS might be:
30045 (service nginx-service-type
30046 (nginx-configuration
30049 (nginx-server-configuration
30050 (listen '("443 ssl"))
30051 (server-name "git.my-host.org")
30053 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
30054 (ssl-certificate-key
30055 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
30058 (git-http-nginx-location-configuration
30059 (git-http-configuration (uri-path "/"))))))))))
30062 This example assumes that you are using Let's Encrypt to get your TLS
30063 certificate. @xref{Certificate Services}. The default @code{certbot}
30064 service will redirect all HTTP traffic on @code{git.my-host.org} to
30065 HTTPS@. You will also need to add an @code{fcgiwrap} proxy to your
30066 system services. @xref{Web Services}.
30069 @subsubheading Cgit Service
30071 @cindex Cgit service
30072 @cindex Git, web interface
30073 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
30074 repositories written in C.
30076 The following example will configure the service with default values.
30077 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
30080 (service cgit-service-type)
30083 The @code{file-object} type designates either a file-like object
30084 (@pxref{G-Expressions, file-like objects}) or a string.
30086 @c %start of fragment
30088 Available @code{cgit-configuration} fields are:
30090 @deftypevr {@code{cgit-configuration} parameter} package package
30095 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
30096 NGINX configuration.
30100 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
30101 Specifies a command which will be invoked to format the content of about
30102 pages (both top-level and for each repository).
30104 Defaults to @samp{""}.
30108 @deftypevr {@code{cgit-configuration} parameter} string agefile
30109 Specifies a path, relative to each repository path, which can be used to
30110 specify the date and time of the youngest commit in the repository.
30112 Defaults to @samp{""}.
30116 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
30117 Specifies a command that will be invoked for authenticating repository
30120 Defaults to @samp{""}.
30124 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
30125 Flag which, when set to @samp{age}, enables date ordering in the branch
30126 ref list, and when set @samp{name} enables ordering by branch name.
30128 Defaults to @samp{"name"}.
30132 @deftypevr {@code{cgit-configuration} parameter} string cache-root
30133 Path used to store the cgit cache entries.
30135 Defaults to @samp{"/var/cache/cgit"}.
30139 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
30140 Number which specifies the time-to-live, in minutes, for the cached
30141 version of repository pages accessed with a fixed SHA1.
30143 Defaults to @samp{-1}.
30147 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
30148 Number which specifies the time-to-live, in minutes, for the cached
30149 version of repository pages accessed without a fixed SHA1.
30151 Defaults to @samp{5}.
30155 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
30156 Number which specifies the time-to-live, in minutes, for the cached
30157 version of the repository summary page.
30159 Defaults to @samp{5}.
30163 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
30164 Number which specifies the time-to-live, in minutes, for the cached
30165 version of the repository index page.
30167 Defaults to @samp{5}.
30171 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
30172 Number which specifies the time-to-live, in minutes, for the result of
30173 scanning a path for Git repositories.
30175 Defaults to @samp{15}.
30179 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
30180 Number which specifies the time-to-live, in minutes, for the cached
30181 version of the repository about page.
30183 Defaults to @samp{15}.
30187 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
30188 Number which specifies the time-to-live, in minutes, for the cached
30189 version of snapshots.
30191 Defaults to @samp{5}.
30195 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
30196 The maximum number of entries in the cgit cache. When set to @samp{0},
30197 caching is disabled.
30199 Defaults to @samp{0}.
30203 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
30204 Sort items in the repo list case sensitively.
30206 Defaults to @samp{#t}.
30210 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
30211 List of common prefixes which, when combined with a repository URL,
30212 generates valid clone URLs for the repository.
30214 Defaults to @samp{()}.
30218 @deftypevr {@code{cgit-configuration} parameter} list clone-url
30219 List of @code{clone-url} templates.
30221 Defaults to @samp{()}.
30225 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
30226 Command which will be invoked to format commit messages.
30228 Defaults to @samp{""}.
30232 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
30233 Flag which, when set to @samp{date}, enables strict date ordering in the
30234 commit log, and when set to @samp{topo} enables strict topological
30237 Defaults to @samp{"git log"}.
30241 @deftypevr {@code{cgit-configuration} parameter} file-object css
30242 URL which specifies the css document to include in all cgit pages.
30244 Defaults to @samp{"/share/cgit/cgit.css"}.
30248 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
30249 Specifies a command which will be invoked to format names and email
30250 address of committers, authors, and taggers, as represented in various
30251 places throughout the cgit interface.
30253 Defaults to @samp{""}.
30257 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
30258 Flag which, when set to @samp{#t}, will make cgit generate a HTML
30259 fragment suitable for embedding in other HTML pages.
30261 Defaults to @samp{#f}.
30265 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
30266 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
30267 commit history graph to the left of the commit messages in the
30268 repository log page.
30270 Defaults to @samp{#f}.
30274 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
30275 Flag which, when set to @samp{#t}, allows all filter settings to be
30276 overridden in repository-specific cgitrc files.
30278 Defaults to @samp{#f}.
30282 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
30283 Flag which, when set to @samp{#t}, allows users to follow a file in the
30286 Defaults to @samp{#f}.
30290 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
30291 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
30294 Defaults to @samp{#t}.
30298 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
30299 Flag which, when set to @samp{#t}, will make cgit generate extra links
30300 "summary", "commit", "tree" for each repo in the repository index.
30302 Defaults to @samp{#f}.
30306 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
30307 Flag which, when set to @samp{#t}, will make cgit display the owner of
30308 each repo in the repository index.
30310 Defaults to @samp{#t}.
30314 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
30315 Flag which, when set to @samp{#t}, will make cgit print the number of
30316 modified files for each commit on the repository log page.
30318 Defaults to @samp{#f}.
30322 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
30323 Flag which, when set to @samp{#t}, will make cgit print the number of
30324 added and removed lines for each commit on the repository log page.
30326 Defaults to @samp{#f}.
30330 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
30331 Flag which, when set to @code{#t}, will make cgit display remote
30332 branches in the summary and refs views.
30334 Defaults to @samp{#f}.
30338 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
30339 Flag which, when set to @code{1}, will make cgit use the subject of the
30340 parent commit as link text when generating links to parent commits in
30343 Defaults to @samp{#f}.
30347 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
30348 Flag which, when set to @samp{#t}, will make cgit use the subject of the
30349 parent commit as link text when generating links to parent commits in
30352 Defaults to @samp{#f}.
30356 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
30357 Flag which, when set to @samp{#t}, will make cgit generate linenumber
30358 links for plaintext blobs printed in the tree view.
30360 Defaults to @samp{#t}.
30364 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
30365 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
30366 set any repo specific settings.
30368 Defaults to @samp{#f}.
30372 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
30373 URL used as link to a shortcut icon for cgit.
30375 Defaults to @samp{"/favicon.ico"}.
30379 @deftypevr {@code{cgit-configuration} parameter} string footer
30380 The content of the file specified with this option will be included
30381 verbatim at the bottom of all pages (i.e.@: it replaces the standard
30382 "generated by..."@: message).
30384 Defaults to @samp{""}.
30388 @deftypevr {@code{cgit-configuration} parameter} string head-include
30389 The content of the file specified with this option will be included
30390 verbatim in the HTML HEAD section on all pages.
30392 Defaults to @samp{""}.
30396 @deftypevr {@code{cgit-configuration} parameter} string header
30397 The content of the file specified with this option will be included
30398 verbatim at the top of all pages.
30400 Defaults to @samp{""}.
30404 @deftypevr {@code{cgit-configuration} parameter} file-object include
30405 Name of a configfile to include before the rest of the current config-
30408 Defaults to @samp{""}.
30412 @deftypevr {@code{cgit-configuration} parameter} string index-header
30413 The content of the file specified with this option will be included
30414 verbatim above the repository index.
30416 Defaults to @samp{""}.
30420 @deftypevr {@code{cgit-configuration} parameter} string index-info
30421 The content of the file specified with this option will be included
30422 verbatim below the heading on the repository index page.
30424 Defaults to @samp{""}.
30428 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
30429 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
30430 in the servers timezone.
30432 Defaults to @samp{#f}.
30436 @deftypevr {@code{cgit-configuration} parameter} file-object logo
30437 URL which specifies the source of an image which will be used as a logo
30440 Defaults to @samp{"/share/cgit/cgit.png"}.
30444 @deftypevr {@code{cgit-configuration} parameter} string logo-link
30445 URL loaded when clicking on the cgit logo image.
30447 Defaults to @samp{""}.
30451 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
30452 Command which will be invoked to format the Owner column of the main
30455 Defaults to @samp{""}.
30459 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
30460 Number of items to display in atom feeds view.
30462 Defaults to @samp{10}.
30466 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
30467 Number of entries to list per page in "log" view.
30469 Defaults to @samp{50}.
30473 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
30474 Number of commit message characters to display in "log" view.
30476 Defaults to @samp{80}.
30480 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
30481 Specifies the number of entries to list per page on the repository index
30484 Defaults to @samp{50}.
30488 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
30489 Specifies the maximum number of repo description characters to display
30490 on the repository index page.
30492 Defaults to @samp{80}.
30496 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
30497 Specifies the maximum size of a blob to display HTML for in KBytes.
30499 Defaults to @samp{0}.
30503 @deftypevr {@code{cgit-configuration} parameter} string max-stats
30504 Maximum statistics period. Valid values are @samp{week},@samp{month},
30505 @samp{quarter} and @samp{year}.
30507 Defaults to @samp{""}.
30511 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
30512 Mimetype for the specified filename extension.
30514 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
30515 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
30516 "image/png") (svg "image/svg+xml"))}.
30520 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
30521 Specifies the file to use for automatic mimetype lookup.
30523 Defaults to @samp{""}.
30527 @deftypevr {@code{cgit-configuration} parameter} string module-link
30528 Text which will be used as the formatstring for a hyperlink when a
30529 submodule is printed in a directory listing.
30531 Defaults to @samp{""}.
30535 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
30536 If set to the value @samp{#t} caching will be disabled.
30538 Defaults to @samp{#f}.
30542 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
30543 If set to @samp{#t} showing full author email addresses will be
30546 Defaults to @samp{#f}.
30550 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
30551 Flag which, when set to @samp{#t}, will make cgit omit the standard
30552 header on all pages.
30554 Defaults to @samp{#f}.
30558 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
30559 A list of subdirectories inside of @code{repository-directory}, relative
30560 to it, that should loaded as Git repositories. An empty list means that
30561 all subdirectories will be loaded.
30563 Defaults to @samp{()}.
30567 @deftypevr {@code{cgit-configuration} parameter} file-object readme
30568 Text which will be used as default value for @code{cgit-repo-readme}.
30570 Defaults to @samp{""}.
30574 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
30575 If set to @code{#t} and @code{repository-directory} is enabled, if any
30576 repositories are found with a suffix of @code{.git}, this suffix will be
30577 removed for the URL and name.
30579 Defaults to @samp{#f}.
30583 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
30584 Maximum number of files to consider when detecting renames.
30586 Defaults to @samp{-1}.
30590 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
30591 The way in which repositories in each section are sorted.
30593 Defaults to @samp{""}.
30597 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
30598 Text used as content for the @code{robots} meta-tag.
30600 Defaults to @samp{("noindex" "nofollow")}.
30604 @deftypevr {@code{cgit-configuration} parameter} string root-desc
30605 Text printed below the heading on the repository index page.
30607 Defaults to @samp{"a fast webinterface for the git dscm"}.
30611 @deftypevr {@code{cgit-configuration} parameter} string root-readme
30612 The content of the file specified with this option will be included
30613 verbatim below the ``about'' link on the repository index page.
30615 Defaults to @samp{""}.
30619 @deftypevr {@code{cgit-configuration} parameter} string root-title
30620 Text printed as heading on the repository index page.
30622 Defaults to @samp{""}.
30626 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
30627 If set to @samp{#t} and repository-directory is enabled,
30628 repository-directory will recurse into directories whose name starts
30629 with a period. Otherwise, repository-directory will stay away from such
30630 directories, considered as ``hidden''. Note that this does not apply to
30631 the @file{.git} directory in non-bare repos.
30633 Defaults to @samp{#f}.
30637 @deftypevr {@code{cgit-configuration} parameter} list snapshots
30638 Text which specifies the default set of snapshot formats that cgit
30639 generates links for.
30641 Defaults to @samp{()}.
30645 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
30646 Name of the directory to scan for repositories (represents
30649 Defaults to @samp{"/srv/git"}.
30653 @deftypevr {@code{cgit-configuration} parameter} string section
30654 The name of the current repository section - all repositories defined
30655 after this option will inherit the current section name.
30657 Defaults to @samp{""}.
30661 @deftypevr {@code{cgit-configuration} parameter} string section-sort
30662 Flag which, when set to @samp{1}, will sort the sections on the
30663 repository listing by name.
30665 Defaults to @samp{""}.
30669 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
30670 A number which, if defined prior to repository-directory, specifies how
30671 many path elements from each repo path to use as a default section name.
30673 Defaults to @samp{0}.
30677 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
30678 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
30681 Defaults to @samp{#f}.
30685 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
30686 Specifies a command which will be invoked to format plaintext blobs in
30689 Defaults to @samp{""}.
30693 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
30694 Specifies the number of branches to display in the repository ``summary''
30697 Defaults to @samp{10}.
30701 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
30702 Specifies the number of log entries to display in the repository
30705 Defaults to @samp{10}.
30709 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
30710 Specifies the number of tags to display in the repository ``summary''
30713 Defaults to @samp{10}.
30717 @deftypevr {@code{cgit-configuration} parameter} string strict-export
30718 Filename which, if specified, needs to be present within the repository
30719 for cgit to allow access to that repository.
30721 Defaults to @samp{""}.
30725 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
30726 URL which, if specified, will be used as root for all cgit links.
30728 Defaults to @samp{"/"}.
30732 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
30733 A list of @dfn{cgit-repo} records to use with config.
30735 Defaults to @samp{()}.
30737 Available @code{repository-cgit-configuration} fields are:
30739 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
30740 A mask of snapshot formats for this repo that cgit generates links for,
30741 restricted by the global @code{snapshots} setting.
30743 Defaults to @samp{()}.
30747 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
30748 Override the default @code{source-filter}.
30750 Defaults to @samp{""}.
30754 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
30755 The relative URL used to access the repository.
30757 Defaults to @samp{""}.
30761 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
30762 Override the default @code{about-filter}.
30764 Defaults to @samp{""}.
30768 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
30769 Flag which, when set to @samp{age}, enables date ordering in the branch
30770 ref list, and when set to @samp{name} enables ordering by branch name.
30772 Defaults to @samp{""}.
30776 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
30777 A list of URLs which can be used to clone repo.
30779 Defaults to @samp{()}.
30783 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
30784 Override the default @code{commit-filter}.
30786 Defaults to @samp{""}.
30790 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
30791 Flag which, when set to @samp{date}, enables strict date ordering in the
30792 commit log, and when set to @samp{topo} enables strict topological
30795 Defaults to @samp{""}.
30799 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
30800 The name of the default branch for this repository. If no such branch
30801 exists in the repository, the first branch name (when sorted) is used as
30802 default instead. By default branch pointed to by HEAD, or ``master'' if
30803 there is no suitable HEAD.
30805 Defaults to @samp{""}.
30809 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
30810 The value to show as repository description.
30812 Defaults to @samp{""}.
30816 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
30817 The value to show as repository homepage.
30819 Defaults to @samp{""}.
30823 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
30824 Override the default @code{email-filter}.
30826 Defaults to @samp{""}.
30830 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
30831 A flag which can be used to disable the global setting
30832 @code{enable-commit-graph?}.
30834 Defaults to @samp{disabled}.
30838 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
30839 A flag which can be used to disable the global setting
30840 @code{enable-log-filecount?}.
30842 Defaults to @samp{disabled}.
30846 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
30847 A flag which can be used to disable the global setting
30848 @code{enable-log-linecount?}.
30850 Defaults to @samp{disabled}.
30854 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
30855 Flag which, when set to @code{#t}, will make cgit display remote
30856 branches in the summary and refs views.
30858 Defaults to @samp{disabled}.
30862 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
30863 A flag which can be used to override the global setting
30864 @code{enable-subject-links?}.
30866 Defaults to @samp{disabled}.
30870 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
30871 A flag which can be used to override the global setting
30872 @code{enable-html-serving?}.
30874 Defaults to @samp{disabled}.
30878 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
30879 Flag which, when set to @code{#t}, hides the repository from the
30882 Defaults to @samp{#f}.
30886 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
30887 Flag which, when set to @samp{#t}, ignores the repository.
30889 Defaults to @samp{#f}.
30893 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
30894 URL which specifies the source of an image which will be used as a logo
30895 on this repo’s pages.
30897 Defaults to @samp{""}.
30901 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
30902 URL loaded when clicking on the cgit logo image.
30904 Defaults to @samp{""}.
30908 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
30909 Override the default @code{owner-filter}.
30911 Defaults to @samp{""}.
30915 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
30916 Text which will be used as the formatstring for a hyperlink when a
30917 submodule is printed in a directory listing. The arguments for the
30918 formatstring are the path and SHA1 of the submodule commit.
30920 Defaults to @samp{""}.
30924 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
30925 Text which will be used as the formatstring for a hyperlink when a
30926 submodule with the specified subdirectory path is printed in a directory
30929 Defaults to @samp{()}.
30933 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
30934 Override the default maximum statistics period.
30936 Defaults to @samp{""}.
30940 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
30941 The value to show as repository name.
30943 Defaults to @samp{""}.
30947 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
30948 A value used to identify the owner of the repository.
30950 Defaults to @samp{""}.
30954 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
30955 An absolute path to the repository directory.
30957 Defaults to @samp{""}.
30961 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
30962 A path (relative to repo) which specifies a file to include verbatim as
30963 the ``About'' page for this repo.
30965 Defaults to @samp{""}.
30969 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
30970 The name of the current repository section - all repositories defined
30971 after this option will inherit the current section name.
30973 Defaults to @samp{""}.
30977 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
30978 Extra options will be appended to cgitrc file.
30980 Defaults to @samp{()}.
30986 @deftypevr {@code{cgit-configuration} parameter} list extra-options
30987 Extra options will be appended to cgitrc file.
30989 Defaults to @samp{()}.
30994 @c %end of fragment
30996 However, it could be that you just want to get a @code{cgitrc} up and
30997 running. In that case, you can pass an @code{opaque-cgit-configuration}
30998 as a record to @code{cgit-service-type}. As its name indicates, an
30999 opaque configuration does not have easy reflective capabilities.
31001 Available @code{opaque-cgit-configuration} fields are:
31003 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
31007 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
31008 The contents of the @code{cgitrc}, as a string.
31011 For example, if your @code{cgitrc} is just the empty string, you
31012 could instantiate a cgit service like this:
31015 (service cgit-service-type
31016 (opaque-cgit-configuration
31020 @subsubheading Gitolite Service
31022 @cindex Gitolite service
31023 @cindex Git, hosting
31024 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
31025 repositories on a central server.
31027 Gitolite can handle multiple repositories and users, and supports flexible
31028 configuration of the permissions for the users on the repositories.
31030 The following example will configure Gitolite using the default @code{git}
31031 user, and the provided SSH public key.
31034 (service gitolite-service-type
31035 (gitolite-configuration
31036 (admin-pubkey (plain-file
31038 "ssh-rsa AAAA... guix@@example.com"))))
31041 Gitolite is configured through a special admin repository which you can clone,
31042 for example, if you setup Gitolite on @code{example.com}, you would run the
31043 following command to clone the admin repository.
31046 git clone git@@example.com:gitolite-admin
31049 When the Gitolite service is activated, the provided @code{admin-pubkey} will
31050 be inserted in to the @file{keydir} directory in the gitolite-admin
31051 repository. If this results in a change in the repository, it will be
31052 committed using the message ``gitolite setup by GNU Guix''.
31054 @deftp {Data Type} gitolite-configuration
31055 Data type representing the configuration for @code{gitolite-service-type}.
31058 @item @code{package} (default: @var{gitolite})
31059 Gitolite package to use.
31061 @item @code{user} (default: @var{git})
31062 User to use for Gitolite. This will be user that you use when accessing
31065 @item @code{group} (default: @var{git})
31066 Group to use for Gitolite.
31068 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
31069 Directory in which to store the Gitolite configuration and repositories.
31071 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
31072 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
31073 representing the configuration for Gitolite.
31075 @item @code{admin-pubkey} (default: @var{#f})
31076 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
31077 setup Gitolite. This will be inserted in to the @file{keydir} directory
31078 within the gitolite-admin repository.
31080 To specify the SSH key as a string, use the @code{plain-file} function.
31083 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
31089 @deftp {Data Type} gitolite-rc-file
31090 Data type representing the Gitolite RC file.
31093 @item @code{umask} (default: @code{#o0077})
31094 This controls the permissions Gitolite sets on the repositories and their
31097 A value like @code{#o0027} will give read access to the group used by Gitolite
31098 (by default: @code{git}). This is necessary when using Gitolite with software
31099 like cgit or gitweb.
31101 @item @code{git-config-keys} (default: @code{""})
31102 Gitolite allows you to set git config values using the @samp{config}
31103 keyword. This setting allows control over the config keys to accept.
31105 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
31106 Set the role names allowed to be used by users running the perms command.
31108 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
31109 This setting controls the commands and features to enable within Gitolite.
31115 @node Game Services
31116 @subsection Game Services
31118 @subsubheading The Battle for Wesnoth Service
31120 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
31121 based tactical strategy game, with several single player campaigns, and
31122 multiplayer games (both networked and local).
31124 @defvar {Scheme Variable} wesnothd-service-type
31125 Service type for the wesnothd service. Its value must be a
31126 @code{wesnothd-configuration} object. To run wesnothd in the default
31127 configuration, instantiate it as:
31130 (service wesnothd-service-type)
31134 @deftp {Data Type} wesnothd-configuration
31135 Data type representing the configuration of @command{wesnothd}.
31138 @item @code{package} (default: @code{wesnoth-server})
31139 The wesnoth server package to use.
31141 @item @code{port} (default: @code{15000})
31142 The port to bind the server to.
31147 @node PAM Mount Service
31148 @subsection PAM Mount Service
31151 The @code{(gnu services pam-mount)} module provides a service allowing
31152 users to mount volumes when they log in. It should be able to mount any
31153 volume format supported by the system.
31155 @defvar {Scheme Variable} pam-mount-service-type
31156 Service type for PAM Mount support.
31159 @deftp {Data Type} pam-mount-configuration
31160 Data type representing the configuration of PAM Mount.
31162 It takes the following parameters:
31166 The configuration rules that will be used to generate
31167 @file{/etc/security/pam_mount.conf.xml}.
31169 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
31170 Guile Reference Manual}), and the default ones don't mount anything for
31174 `((debug (@@ (enable "0")))
31175 (mntoptions (@@ (allow ,(string-join
31176 '("nosuid" "nodev" "loop"
31177 "encryption" "fsck" "nonempty"
31178 "allow_root" "allow_other")
31180 (mntoptions (@@ (require "nosuid,nodev")))
31181 (logout (@@ (wait "0")
31185 (mkmountpoint (@@ (enable "1")
31189 Some @code{volume} elements must be added to automatically mount volumes
31190 at login. Here's an example allowing the user @code{alice} to mount her
31191 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
31192 the partition where he stores his data:
31195 (define pam-mount-rules
31196 `((debug (@@ (enable "0")))
31197 (volume (@@ (user "alice")
31200 (mountpoint "/home/alice")))
31201 (volume (@@ (user "bob")
31204 (mountpoint "/home/bob/data")
31205 (options "defaults,autodefrag,compress")))
31206 (mntoptions (@@ (allow ,(string-join
31207 '("nosuid" "nodev" "loop"
31208 "encryption" "fsck" "nonempty"
31209 "allow_root" "allow_other")
31211 (mntoptions (@@ (require "nosuid,nodev")))
31212 (logout (@@ (wait "0")
31216 (mkmountpoint (@@ (enable "1")
31217 (remove "true")))))
31219 (service pam-mount-service-type
31220 (pam-mount-configuration
31221 (rules pam-mount-rules)))
31224 The complete list of possible options can be found in the man page for
31225 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
31230 @node Guix Services
31231 @subsection Guix Services
31233 @subsubheading Guix Build Coordinator
31234 The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
31235 Coordinator} aids in distributing derivation builds among machines
31236 running an @dfn{agent}. The build daemon is still used to build the
31237 derivations, but the Guix Build Coordinator manages allocating builds
31238 and working with the results.
31241 This service is considered experimental. Configuration options may be
31242 changed in a backwards-incompatible manner, and not all features have
31243 been thorougly tested.
31246 The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
31247 more connected @dfn{agent} processes. The coordinator process handles
31248 clients submitting builds, and allocating builds to agents. The agent
31249 processes talk to a build daemon to actually perform the builds, then
31250 send the results back to the coordinator.
31252 There is a script to run the coordinator component of the Guix Build
31253 Coordinator, but the Guix service uses a custom Guile script instead, to
31254 provide better integration with G-expressions used in the configuration.
31256 @defvar {Scheme Variable} guix-build-coordinator-service-type
31257 Service type for the Guix Build Coordinator. Its value must be a
31258 @code{guix-build-coordinator-configuration} object.
31261 @deftp {Data Type} guix-build-coordinator-configuration
31262 Data type representing the configuration of the Guix Build Coordinator.
31265 @item @code{package} (default: @code{guix-build-coordinator})
31266 The Guix Build Coordinator package to use.
31268 @item @code{user} (default: @code{"guix-build-coordinator"})
31269 The system user to run the service as.
31271 @item @code{group} (default: @code{"guix-build-coordinator"})
31272 The system group to run the service as.
31274 @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
31275 The URI to use for the database.
31277 @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
31278 The URI describing how to listen to requests from agent processes.
31280 @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
31281 The URI describing how to listen to requests from clients. The client
31282 API allows submitting builds and currently isn't authenticated, so take
31283 care when configuring this value.
31285 @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
31286 A G-expression for the allocation strategy to be used. This is a
31287 procedure that takes the datastore as an argument and populates the
31288 allocation plan in the database.
31290 @item @code{hooks} (default: @var{'()})
31291 An association list of hooks. These provide a way to execute arbitrary
31292 code upon certain events, like a build result being processed.
31294 @item @code{guile} (default: @code{guile-3.0-latest})
31295 The Guile package with which to run the Guix Build Coordinator.
31300 @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
31301 Service type for a Guix Build Coordinator agent. Its value must be a
31302 @code{guix-build-coordinator-agent-configuration} object.
31305 @deftp {Data Type} guix-build-coordinator-agent-configuration
31306 Data type representing the configuration a Guix Build Coordinator agent.
31309 @item @code{package} (default: @code{guix-build-coordinator})
31310 The Guix Build Coordinator package to use.
31312 @item @code{user} (default: @code{"guix-build-coordinator-agent"})
31313 The system user to run the service as.
31315 @item @code{coordinator} (default: @code{"http://localhost:8745"})
31316 The URI to use when connecting to the coordinator.
31318 @item @code{authentication}
31319 Record describing how this agent should authenticate with the
31320 coordinator. Possible record types are described below.
31322 @item @code{systems} (default: @code{#f})
31323 The systems for which this agent should fetch builds. The agent process
31324 will use the current system it's running on as the default.
31326 @item @code{max-parallel-builds} (default: @code{1})
31327 The number of builds to perform in parallel.
31329 @item @code{max-1min-load-average} (default: @code{#f})
31330 Load average value to look at when considering starting new builds, if
31331 the 1 minute load average exceeds this value, the agent will wait before
31332 starting new builds.
31334 This will be unspecified if the value is @code{#f}, and the agent will
31335 use the number of cores reported by the system as the max 1 minute load
31338 @item @code{derivation-substitute-urls} (default: @code{#f})
31339 URLs from which to attempt to fetch substitutes for derivations, if the
31340 derivations aren't already available.
31342 @item @code{non-derivation-substitute-urls} (default: @code{#f})
31343 URLs from which to attempt to fetch substitutes for build inputs, if the
31344 input store items aren't already available.
31349 @deftp {Data Type} guix-build-coordinator-agent-password-auth
31350 Data type representing an agent authenticating with a coordinator via a
31355 The UUID of the agent. This should be generated by the coordinator
31356 process, stored in the coordinator database, and used by the intended
31359 @item @code{password}
31360 The password to use when connecting to the coordinator.
31365 @deftp {Data Type} guix-build-coordinator-agent-password-file-auth
31366 Data type representing an agent authenticating with a coordinator via a
31367 UUID and password read from a file.
31371 The UUID of the agent. This should be generated by the coordinator
31372 process, stored in the coordinator database, and used by the intended
31375 @item @code{password-file}
31376 A file containing the password to use when connecting to the
31382 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth
31383 Data type representing an agent authenticating with a coordinator via a
31384 dynamic auth token and agent name.
31387 @item @code{agent-name}
31388 Name of an agent, this is used to match up to an existing entry in the
31389 database if there is one. When no existing entry is found, a new entry
31390 is automatically added.
31393 Dynamic auth token, this is created and stored in the coordinator
31394 database, and is used by the agent to authenticate.
31399 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth-with-file
31400 Data type representing an agent authenticating with a coordinator via a
31401 dynamic auth token read from a file and agent name.
31404 @item @code{agent-name}
31405 Name of an agent, this is used to match up to an existing entry in the
31406 database if there is one. When no existing entry is found, a new entry
31407 is automatically added.
31409 @item @code{token-file}
31410 File containing the dynamic auth token, this is created and stored in
31411 the coordinator database, and is used by the agent to authenticate.
31416 The Guix Build Coordinator package contains a script to query an
31417 instance of the Guix Data Service for derivations to build, and then
31418 submit builds for those derivations to the coordinator. The service
31419 type below assists in running this script. This is an additional tool
31420 that may be useful when building derivations contained within an
31421 instance of the Guix Data Service.
31423 @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
31424 Service type for the
31425 guix-build-coordinator-queue-builds-from-guix-data-service script. Its
31426 value must be a @code{guix-build-coordinator-queue-builds-configuration}
31430 @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
31431 Data type representing the options to the queue builds from guix data
31435 @item @code{package} (default: @code{guix-build-coordinator})
31436 The Guix Build Coordinator package to use.
31438 @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
31439 The system user to run the service as.
31441 @item @code{coordinator} (default: @code{"http://localhost:8746"})
31442 The URI to use when connecting to the coordinator.
31444 @item @code{systems} (default: @code{#f})
31445 The systems for which to fetch derivations to build.
31447 @item @code{systems-and-targets} (default: @code{#f})
31448 An association list of system and target pairs for which to fetch
31449 derivations to build.
31451 @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
31452 The Guix Data Service instance from which to query to find out about
31453 derivations to build.
31455 @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
31456 A file to record which commits have been processed, to avoid needlessly
31457 processing them again if the service is restarted.
31462 @subsubheading Guix Data Service
31463 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
31464 and provides data about GNU Guix. This includes information about
31465 packages, derivations and lint warnings.
31467 The data is stored in a PostgreSQL database, and available through a web
31470 @defvar {Scheme Variable} guix-data-service-type
31471 Service type for the Guix Data Service. Its value must be a
31472 @code{guix-data-service-configuration} object. The service optionally
31473 extends the getmail service, as the guix-commits mailing list is used to
31474 find out about changes in the Guix git repository.
31477 @deftp {Data Type} guix-data-service-configuration
31478 Data type representing the configuration of the Guix Data Service.
31481 @item @code{package} (default: @code{guix-data-service})
31482 The Guix Data Service package to use.
31484 @item @code{user} (default: @code{"guix-data-service"})
31485 The system user to run the service as.
31487 @item @code{group} (default: @code{"guix-data-service"})
31488 The system group to run the service as.
31490 @item @code{port} (default: @code{8765})
31491 The port to bind the web service to.
31493 @item @code{host} (default: @code{"127.0.0.1"})
31494 The host to bind the web service to.
31496 @item @code{getmail-idle-mailboxes} (default: @code{#f})
31497 If set, this is the list of mailboxes that the getmail service will be
31498 configured to listen to.
31500 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
31501 If set, this is the @code{getmail-retriever-configuration} object with
31502 which to configure getmail to fetch mail from the guix-commits mailing
31505 @item @code{extra-options} (default: @var{'()})
31506 Extra command line options for @code{guix-data-service}.
31508 @item @code{extra-process-jobs-options} (default: @var{'()})
31509 Extra command line options for @code{guix-data-service-process-jobs}.
31514 @node Linux Services
31515 @subsection Linux Services
31518 @cindex out of memory killer
31520 @cindex early out of memory daemon
31521 @subsubheading Early OOM Service
31523 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
31524 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
31525 space and provides a more responsive and configurable alternative to the
31526 in-kernel OOM killer. It is useful to prevent the system from becoming
31527 unresponsive when it runs out of memory.
31529 @deffn {Scheme Variable} earlyoom-service-type
31530 The service type for running @command{earlyoom}, the Early OOM daemon.
31531 Its value must be a @code{earlyoom-configuration} object, described
31532 below. The service can be instantiated in its default configuration
31536 (service earlyoom-service-type)
31540 @deftp {Data Type} earlyoom-configuration
31541 This is the configuration record for the @code{earlyoom-service-type}.
31544 @item @code{earlyoom} (default: @var{earlyoom})
31545 The Earlyoom package to use.
31547 @item @code{minimum-available-memory} (default: @code{10})
31548 The threshold for the minimum @emph{available} memory, in percentages.
31550 @item @code{minimum-free-swap} (default: @code{10})
31551 The threshold for the minimum free swap memory, in percentages.
31553 @item @code{prefer-regexp} (default: @code{#f})
31554 A regular expression (as a string) to match the names of the processes
31555 that should be preferably killed.
31557 @item @code{avoid-regexp} (default: @code{#f})
31558 A regular expression (as a string) to match the names of the processes
31559 that should @emph{not} be killed.
31561 @item @code{memory-report-interval} (default: @code{0})
31562 The interval in seconds at which a memory report is printed. It is
31563 disabled by default.
31565 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
31566 A boolean indicating whether the positive adjustments set in
31567 @file{/proc/*/oom_score_adj} should be ignored.
31569 @item @code{show-debug-messages?} (default: @code{#f})
31570 A boolean indicating whether debug messages should be printed. The logs
31571 are saved at @file{/var/log/earlyoom.log}.
31573 @item @code{send-notification-command} (default: @code{#f})
31574 This can be used to provide a custom command used for sending
31580 @cindex kernel module loader
31581 @subsubheading Kernel Module Loader Service
31583 The kernel module loader service allows one to load loadable kernel
31584 modules at boot. This is especially useful for modules that don't
31585 autoload and need to be manually loaded, as is the case with
31588 @deffn {Scheme Variable} kernel-module-loader-service-type
31589 The service type for loading loadable kernel modules at boot with
31590 @command{modprobe}. Its value must be a list of strings representing
31591 module names. For example loading the drivers provided by
31592 @code{ddcci-driver-linux}, in debugging mode by passing some module
31593 parameters, can be done as follow:
31596 (use-modules (gnu) (gnu services))
31597 (use-package-modules linux)
31598 (use-service-modules linux)
31600 (define ddcci-config
31601 (plain-file "ddcci.conf"
31602 "options ddcci dyndbg delay=120"))
31606 (services (cons* (service kernel-module-loader-service-type
31607 '("ddcci" "ddcci_backlight"))
31608 (simple-service 'ddcci-config etc-service-type
31609 (list `("modprobe.d/ddcci.conf"
31612 (kernel-loadable-modules (list ddcci-driver-linux)))
31617 @cindex Platform Reliability, Availability and Serviceability daemon
31618 @subsubheading Rasdaemon Service
31620 The Rasdaemon service provides a daemon which monitors platform
31621 @acronym{RAS, Reliability@comma{} Availability@comma{} and Serviceability} reports from
31622 Linux kernel trace events, logging them to syslogd.
31624 Reliability, Availability and Serviceability is a concept used on servers meant
31625 to measure their robustness.
31627 @strong{Relability} is the probability that a system will produce correct
31631 @item Generally measured as Mean Time Between Failures (MTBF), and
31632 @item Enhanced by features that help to avoid, detect and repair hardware
31636 @strong{Availability} is the probability that a system is operational at a
31640 @item Generally measured as a percentage of downtime per a period of time, and
31641 @item Often uses mechanisms to detect and correct hardware faults in runtime.
31644 @strong{Serviceability} is the simplicity and speed with which a system can be
31645 repaired or maintained:
31648 @item Generally measured on Mean Time Between Repair (MTBR).
31652 Among the monitoring measures, the most usual ones include:
31655 @item CPU – detect errors at instruction execution and at L1/L2/L3 caches;
31656 @item Memory – add error correction logic (ECC) to detect and correct errors;
31657 @item I/O – add CRC checksums for transferred data;
31658 @item Storage – RAID, journal file systems, checksums, Self-Monitoring,
31659 Analysis and Reporting Technology (SMART).
31662 By monitoring the number of occurrences of error detections, it is possible to
31663 identify if the probability of hardware errors is increasing, and, on such
31664 case, do a preventive maintenance to replace a degraded component while those
31665 errors are correctable.
31667 For detailed information about the types of error events gathered and how to
31668 make sense of them, see the kernel administrator's guide at
31669 @url{https://www.kernel.org/doc/html/latest/admin-guide/ras.html}.
31671 @defvr {Scheme Variable} rasdaemon-service-type
31672 Service type for the @command{rasdaemon} service. It accepts a
31673 @code{rasdaemon-configuration} object. Instantiating like
31676 (service rasdaemon-service-type)
31679 will load with a default configuration, which monitors all events and logs to
31683 @deftp {Data Type} rasdaemon-configuration
31684 The data type representing the configuration of @command{rasdaemon}.
31687 @item @code{record?} (default: @code{#f})
31689 A boolean indicating whether to record the events in an SQLite database. This
31690 provides a more structured access to the information contained in the log file.
31691 The database location is hard-coded to @file{/var/lib/rasdaemon/ras-mc_event.db}.
31697 @cindex compressed swap
31698 @cindex Compressed RAM-based block devices
31699 @subsubheading Zram Device Service
31701 The Zram device service provides a compressed swap device in system
31702 memory. The Linux Kernel documentation has more information about
31703 @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
31706 @deffn {Scheme Variable} zram-device-service-type
31707 This service creates the zram block device, formats it as swap and
31708 enables it as a swap device. The service's value is a
31709 @code{zram-device-configuration} record.
31711 @deftp {Data Type} zram-device-configuration
31712 This is the data type representing the configuration for the zram-device
31716 @item @code{size} (default @code{"1G"})
31717 This is the amount of space you wish to provide for the zram device. It
31718 accepts a string and can be a number of bytes or use a suffix, eg.:
31719 @code{"512M"} or @code{1024000}.
31720 @item @code{compression-algorithm} (default @code{'lzo})
31721 This is the compression algorithm you wish to use. It is difficult to
31722 list all the possible compression options, but common ones supported by
31723 Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
31724 @item @code{memory-limit} (default @code{0})
31725 This is the maximum amount of memory which the zram device can use.
31726 Setting it to '0' disables the limit. While it is generally expected
31727 that compression will be 2:1, it is possible that uncompressable data
31728 can be written to swap and this is a method to limit how much memory can
31729 be used. It accepts a string and can be a number of bytes or use a
31730 suffix, eg.: @code{"2G"}.
31731 @item @code{priority} (default @code{-1})
31732 This is the priority of the swap device created from the zram device.
31733 @code{swapon} accepts values between -1 and 32767, with higher values
31734 indicating higher priority. Higher priority swap will generally be used
31741 @node Hurd Services
31742 @subsection Hurd Services
31744 @defvr {Scheme Variable} hurd-console-service-type
31745 This service starts the fancy @code{VGA} console client on the Hurd.
31747 The service's value is a @code{hurd-console-configuration} record.
31750 @deftp {Data Type} hurd-console-configuration
31751 This is the data type representing the configuration for the
31752 hurd-console-service.
31755 @item @code{hurd} (default: @var{hurd})
31756 The Hurd package to use.
31760 @defvr {Scheme Variable} hurd-getty-service-type
31761 This service starts a tty using the Hurd @code{getty} program.
31763 The service's value is a @code{hurd-getty-configuration} record.
31766 @deftp {Data Type} hurd-getty-configuration
31767 This is the data type representing the configuration for the
31768 hurd-getty-service.
31771 @item @code{hurd} (default: @var{hurd})
31772 The Hurd package to use.
31775 The name of the console this Getty runs on---e.g., @code{"tty1"}.
31777 @item @code{baud-rate} (default: @code{38400})
31778 An integer specifying the baud rate of the tty.
31783 @node Miscellaneous Services
31784 @subsection Miscellaneous Services
31786 @cindex fingerprint
31787 @subsubheading Fingerprint Service
31789 The @code{(gnu services authentication)} module provides a DBus service to
31790 read and identify fingerprints via a fingerprint sensor.
31792 @defvr {Scheme Variable} fprintd-service-type
31793 The service type for @command{fprintd}, which provides the fingerprint
31794 reading capability.
31797 (service fprintd-service-type)
31802 @subsubheading System Control Service
31804 The @code{(gnu services sysctl)} provides a service to configure kernel
31805 parameters at boot.
31807 @defvr {Scheme Variable} sysctl-service-type
31808 The service type for @command{sysctl}, which modifies kernel parameters
31809 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
31813 (service sysctl-service-type
31814 (sysctl-configuration
31815 (settings '(("net.ipv4.ip_forward" . "1")))))
31818 Since @code{sysctl-service-type} is used in the default lists of
31819 services, @code{%base-services} and @code{%desktop-services}, you can
31820 use @code{modify-services} to change its configuration and add the
31821 kernel parameters that you want (@pxref{Service Reference,
31822 @code{modify-services}}).
31825 (modify-services %base-services
31826 (sysctl-service-type config =>
31827 (sysctl-configuration
31828 (settings (append '(("net.ipv4.ip_forward" . "1"))
31829 %default-sysctl-settings)))))
31834 @deftp {Data Type} sysctl-configuration
31835 The data type representing the configuration of @command{sysctl}.
31838 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
31839 The @command{sysctl} executable to use.
31841 @item @code{settings} (default: @code{%default-sysctl-settings})
31842 An association list specifies kernel parameters and their values.
31846 @defvr {Scheme Variable} %default-sysctl-settings
31847 An association list specifying the default @command{sysctl} parameters
31852 @subsubheading PC/SC Smart Card Daemon Service
31854 The @code{(gnu services security-token)} module provides the following service
31855 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
31856 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
31857 manager that coordinates communications with smart card readers, smart cards
31858 and cryptographic tokens that are connected to the system.
31860 @defvr {Scheme Variable} pcscd-service-type
31861 Service type for the @command{pcscd} service. Its value must be a
31862 @code{pcscd-configuration} object. To run pcscd in the default
31863 configuration, instantiate it as:
31866 (service pcscd-service-type)
31870 @deftp {Data Type} pcscd-configuration
31871 The data type representing the configuration of @command{pcscd}.
31874 @item @code{pcsc-lite} (default: @code{pcsc-lite})
31875 The pcsc-lite package that provides pcscd.
31876 @item @code{usb-drivers} (default: @code{(list ccid)})
31877 List of packages that provide USB drivers to pcscd. Drivers are expected to be
31878 under @file{pcsc/drivers} in the store directory of the package.
31883 @subsubheading Lirc Service
31885 The @code{(gnu services lirc)} module provides the following service.
31887 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
31888 [#:device #f] [#:driver #f] [#:config-file #f] @
31889 [#:extra-options '()]
31890 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
31891 decodes infrared signals from remote controls.
31893 Optionally, @var{device}, @var{driver} and @var{config-file}
31894 (configuration file name) may be specified. See @command{lircd} manual
31897 Finally, @var{extra-options} is a list of additional command-line options
31898 passed to @command{lircd}.
31902 @subsubheading Spice Service
31904 The @code{(gnu services spice)} module provides the following service.
31906 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
31907 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
31908 that enables sharing the clipboard with a vm and setting the guest display
31909 resolution when the graphical console window resizes.
31912 @cindex inputattach
31913 @subsubheading inputattach Service
31915 @cindex tablet input, for Xorg
31916 @cindex touchscreen input, for Xorg
31917 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
31918 use input devices such as Wacom tablets, touchscreens, or joysticks with the
31919 Xorg display server.
31921 @deffn {Scheme Variable} inputattach-service-type
31922 Type of a service that runs @command{inputattach} on a device and
31923 dispatches events from it.
31926 @deftp {Data Type} inputattach-configuration
31928 @item @code{device-type} (default: @code{"wacom"})
31929 The type of device to connect to. Run @command{inputattach --help}, from the
31930 @code{inputattach} package, to see the list of supported device types.
31932 @item @code{device} (default: @code{"/dev/ttyS0"})
31933 The device file to connect to the device.
31935 @item @code{baud-rate} (default: @code{#f})
31936 Baud rate to use for the serial connection.
31937 Should be a number or @code{#f}.
31939 @item @code{log-file} (default: @code{#f})
31940 If true, this must be the name of a file to log messages to.
31944 @subsubheading Dictionary Service
31946 The @code{(gnu services dict)} module provides the following service:
31948 @defvr {Scheme Variable} dicod-service-type
31949 This is the type of the service that runs the @command{dicod} daemon, an
31950 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
31953 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
31954 Return a service that runs the @command{dicod} daemon, an implementation
31955 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
31957 The optional @var{config} argument specifies the configuration for
31958 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
31959 default it serves the GNU Collaborative International Dictionary of English.
31961 You can add @command{open localhost} to your @file{~/.dico} file to make
31962 @code{localhost} the default server for @command{dico} client
31963 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
31966 @deftp {Data Type} dicod-configuration
31967 Data type representing the configuration of dicod.
31970 @item @code{dico} (default: @var{dico})
31971 Package object of the GNU Dico dictionary server.
31973 @item @code{interfaces} (default: @var{'("localhost")})
31974 This is the list of IP addresses and ports and possibly socket file
31975 names to listen to (@pxref{Server Settings, @code{listen} directive,,
31976 dico, GNU Dico Manual}).
31978 @item @code{handlers} (default: @var{'()})
31979 List of @code{<dicod-handler>} objects denoting handlers (module instances).
31981 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
31982 List of @code{<dicod-database>} objects denoting dictionaries to be served.
31986 @deftp {Data Type} dicod-handler
31987 Data type representing a dictionary handler (module instance).
31991 Name of the handler (module instance).
31993 @item @code{module} (default: @var{#f})
31994 Name of the dicod module of the handler (instance). If it is @code{#f},
31995 the module has the same name as the handler.
31996 (@pxref{Modules,,, dico, GNU Dico Manual}).
31998 @item @code{options}
31999 List of strings or gexps representing the arguments for the module handler
32003 @deftp {Data Type} dicod-database
32004 Data type representing a dictionary database.
32008 Name of the database, will be used in DICT commands.
32010 @item @code{handler}
32011 Name of the dicod handler (module instance) used by this database
32012 (@pxref{Handlers,,, dico, GNU Dico Manual}).
32014 @item @code{complex?} (default: @var{#f})
32015 Whether the database configuration complex. The complex configuration
32016 will need a corresponding @code{<dicod-handler>} object, otherwise not.
32018 @item @code{options}
32019 List of strings or gexps representing the arguments for the database
32020 (@pxref{Databases,,, dico, GNU Dico Manual}).
32024 @defvr {Scheme Variable} %dicod-database:gcide
32025 A @code{<dicod-database>} object serving the GNU Collaborative International
32026 Dictionary of English using the @code{gcide} package.
32029 The following is an example @code{dicod-service} configuration.
32032 (dicod-service #:config
32033 (dicod-configuration
32034 (handlers (list (dicod-handler
32038 (list #~(string-append "dbdir=" #$wordnet))))))
32039 (databases (list (dicod-database
32042 (handler "wordnet")
32043 (options '("database=wn")))
32044 %dicod-database:gcide))))
32048 @subsubheading Docker Service
32050 The @code{(gnu services docker)} module provides the following services.
32052 @defvr {Scheme Variable} docker-service-type
32054 This is the type of the service that runs @url{https://www.docker.com,Docker},
32055 a daemon that can execute application bundles (sometimes referred to as
32056 ``containers'') in isolated environments.
32060 @deftp {Data Type} docker-configuration
32061 This is the data type representing the configuration of Docker and Containerd.
32065 @item @code{package} (default: @code{docker})
32066 The Docker daemon package to use.
32068 @item @code{package} (default: @code{docker-cli})
32069 The Docker client package to use.
32071 @item @code{containerd} (default: @var{containerd})
32072 The Containerd package to use.
32074 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
32075 The Docker user-land networking proxy package to use.
32077 @item @code{enable-proxy?} (default @code{#t})
32078 Enable or disable the use of the Docker user-land networking proxy.
32080 @item @code{debug?} (default @code{#f})
32081 Enable or disable debug output.
32083 @item @code{enable-iptables?} (default @code{#t})
32084 Enable or disable the addition of iptables rules.
32089 @cindex Singularity, container service
32090 @defvr {Scheme Variable} singularity-service-type
32091 This is the type of the service that allows you to run
32092 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
32093 create and run application bundles (aka. ``containers''). The value for this
32094 service is the Singularity package to use.
32096 The service does not install a daemon; instead, it installs helper programs as
32097 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
32098 @command{singularity run} and similar commands.
32102 @subsubheading Auditd Service
32104 The @code{(gnu services auditd)} module provides the following service.
32106 @defvr {Scheme Variable} auditd-service-type
32108 This is the type of the service that runs
32109 @url{https://people.redhat.com/sgrubb/audit/,auditd},
32110 a daemon that tracks security-relevant information on your system.
32112 Examples of things that can be tracked:
32122 Failed login attempts
32129 @command{auditctl} from the @code{audit} package can be used in order
32130 to add or remove events to be tracked (until the next reboot).
32131 In order to permanently track events, put the command line arguments
32132 of auditctl into a file called @code{audit.rules} in the configuration
32133 directory (see below).
32134 @command{aureport} from the @code{audit} package can be used in order
32135 to view a report of all recorded events.
32136 The audit daemon by default logs into the file
32137 @file{/var/log/audit.log}.
32141 @deftp {Data Type} auditd-configuration
32142 This is the data type representing the configuration of auditd.
32146 @item @code{audit} (default: @code{audit})
32147 The audit package to use.
32149 @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
32150 The directory containing the configuration file for the audit package, which
32151 must be named @code{auditd.conf}, and optionally some audit rules to
32152 instantiate on startup.
32158 @subsubheading R-Shiny service
32160 The @code{(gnu services science)} module provides the following service.
32162 @defvr {Scheme Variable} rshiny-service-type
32164 This is a type of service which is used to run a webapp created with
32165 @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
32166 variable and runs the provided script to call @code{runApp}.
32168 @deftp {Data Type} rshiny-configuration
32169 This is the data type representing the configuration of rshiny.
32173 @item @code{package} (default: @code{r-shiny})
32174 The package to use.
32176 @item @code{binary} (defaunlt @code{"rshiny"})
32177 The name of the binary or shell script located at @code{package/bin/} to
32178 run when the service is run.
32180 The common way to create this file is as follows:
32184 (let* ((out (assoc-ref %outputs "out"))
32185 (targetdir (string-append out "/share/" ,name))
32186 (app (string-append out "/bin/" ,name))
32187 (Rbin (string-append (assoc-ref %build-inputs "r-min")
32190 (mkdir-p (string-append out "/bin"))
32191 (call-with-output-file app
32197 runApp(launch.browser=0, port=4202)~%\n"
32206 @subsubheading Nix service
32208 The @code{(gnu services nix)} module provides the following service.
32210 @defvr {Scheme Variable} nix-service-type
32212 This is the type of the service that runs build daemon of the
32213 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
32217 (use-modules (gnu))
32218 (use-service-modules nix)
32219 (use-package-modules package-management)
32223 (packages (append (list nix)
32226 (services (append (list (service nix-service-type))
32230 After @command{guix system reconfigure} configure Nix for your user:
32233 @item Add a Nix channel and update it. See
32234 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
32236 @item Create a symlink to your profile and activate Nix profile:
32240 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
32241 $ source /run/current-system/profile/etc/profile.d/nix.sh
32246 @deftp {Data Type} nix-configuration
32247 This data type represents the configuration of the Nix daemon.
32250 @item @code{nix} (default: @code{nix})
32251 The Nix package to use.
32253 @item @code{sandbox} (default: @code{#t})
32254 Specifies whether builds are sandboxed by default.
32256 @item @code{build-sandbox-items} (default: @code{'()})
32257 This is a list of strings or objects appended to the
32258 @code{build-sandbox-items} field of the configuration file.
32260 @item @code{extra-config} (default: @code{'()})
32261 This is a list of strings or objects appended to the configuration file.
32262 It is used to pass extra text to be added verbatim to the configuration
32265 @item @code{extra-options} (default: @code{'()})
32266 Extra command line options for @code{nix-service-type}.
32270 @node Setuid Programs
32271 @section Setuid Programs
32273 @cindex setuid programs
32274 Some programs need to run with ``root'' privileges, even when they are
32275 launched by unprivileged users. A notorious example is the
32276 @command{passwd} program, which users can run to change their
32277 password, and which needs to access the @file{/etc/passwd} and
32278 @file{/etc/shadow} files---something normally restricted to root, for
32279 obvious security reasons. To address that, these executables are
32280 @dfn{setuid-root}, meaning that they always run with root privileges
32281 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
32282 for more info about the setuid mechanism).
32284 The store itself @emph{cannot} contain setuid programs: that would be a
32285 security issue since any user on the system can write derivations that
32286 populate the store (@pxref{The Store}). Thus, a different mechanism is
32287 used: instead of changing the setuid bit directly on files that are in
32288 the store, we let the system administrator @emph{declare} which programs
32289 should be setuid root.
32291 The @code{setuid-programs} field of an @code{operating-system}
32292 declaration contains a list of G-expressions denoting the names of
32293 programs to be setuid-root (@pxref{Using the Configuration System}).
32294 For instance, the @command{passwd} program, which is part of the Shadow
32295 package, can be designated by this G-expression (@pxref{G-Expressions}):
32298 #~(string-append #$shadow "/bin/passwd")
32301 A default set of setuid programs is defined by the
32302 @code{%setuid-programs} variable of the @code{(gnu system)} module.
32304 @defvr {Scheme Variable} %setuid-programs
32305 A list of G-expressions denoting common programs that are setuid-root.
32307 The list includes commands such as @command{passwd}, @command{ping},
32308 @command{su}, and @command{sudo}.
32311 Under the hood, the actual setuid programs are created in the
32312 @file{/run/setuid-programs} directory at system activation time. The
32313 files in this directory refer to the ``real'' binaries, which are in the
32316 @node X.509 Certificates
32317 @section X.509 Certificates
32319 @cindex HTTPS, certificates
32320 @cindex X.509 certificates
32322 Web servers available over HTTPS (that is, HTTP over the transport-layer
32323 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
32324 that the client can then use to @emph{authenticate} the server. To do
32325 that, clients verify that the server's certificate is signed by a
32326 so-called @dfn{certificate authority} (CA). But to verify the CA's
32327 signature, clients must have first acquired the CA's certificate.
32329 Web browsers such as GNU@tie{}IceCat include their own set of CA
32330 certificates, such that they are able to verify CA signatures
32333 However, most other programs that can talk HTTPS---@command{wget},
32334 @command{git}, @command{w3m}, etc.---need to be told where CA
32335 certificates can be found.
32337 @cindex @code{nss-certs}
32338 In Guix, this is done by adding a package that provides certificates
32339 to the @code{packages} field of the @code{operating-system} declaration
32340 (@pxref{operating-system Reference}). Guix includes one such package,
32341 @code{nss-certs}, which is a set of CA certificates provided as part of
32342 Mozilla's Network Security Services.
32344 Note that it is @emph{not} part of @code{%base-packages}, so you need to
32345 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
32346 most applications and libraries look for certificates by default, points
32347 to the certificates installed globally.
32349 Unprivileged users, including users of Guix on a foreign distro,
32350 can also install their own certificate package in
32351 their profile. A number of environment variables need to be defined so
32352 that applications and libraries know where to find them. Namely, the
32353 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
32354 variables. Some applications add their own environment variables; for
32355 instance, the Git version control system honors the certificate bundle
32356 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
32357 would typically run something like:
32360 guix install nss-certs
32361 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
32362 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
32363 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
32366 As another example, R requires the @env{CURL_CA_BUNDLE} environment
32367 variable to point to a certificate bundle, so you would have to run
32368 something like this:
32371 guix install nss-certs
32372 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
32375 For other applications you may want to look up the required environment
32376 variable in the relevant documentation.
32379 @node Name Service Switch
32380 @section Name Service Switch
32382 @cindex name service switch
32384 The @code{(gnu system nss)} module provides bindings to the
32385 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
32386 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
32387 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
32388 extended with new ``name'' lookup methods for system databases, which
32389 includes host names, service names, user accounts, and more (@pxref{Name
32390 Service Switch, System Databases and Name Service Switch,, libc, The GNU
32391 C Library Reference Manual}).
32393 The NSS configuration specifies, for each system database, which lookup
32394 method is to be used, and how the various methods are chained
32395 together---for instance, under which circumstances NSS should try the
32396 next method in the list. The NSS configuration is given in the
32397 @code{name-service-switch} field of @code{operating-system} declarations
32398 (@pxref{operating-system Reference, @code{name-service-switch}}).
32401 @cindex .local, host name lookup
32402 As an example, the declaration below configures the NSS to use the
32403 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
32404 back-end}, which supports host name lookups over multicast DNS (mDNS)
32405 for host names ending in @code{.local}:
32408 (name-service-switch
32409 (hosts (list %files ;first, check /etc/hosts
32411 ;; If the above did not succeed, try
32412 ;; with 'mdns_minimal'.
32414 (name "mdns_minimal")
32416 ;; 'mdns_minimal' is authoritative for
32417 ;; '.local'. When it returns "not found",
32418 ;; no need to try the next methods.
32419 (reaction (lookup-specification
32420 (not-found => return))))
32422 ;; Then fall back to DNS.
32426 ;; Finally, try with the "full" 'mdns'.
32431 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
32432 contains this configuration, so you will not have to type it if all you
32433 want is to have @code{.local} host lookup working.
32435 Note that, in this case, in addition to setting the
32436 @code{name-service-switch} of the @code{operating-system} declaration,
32437 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
32438 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
32439 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
32440 to the name service cache daemon (@pxref{Base Services,
32441 @code{nscd-service}}).
32443 For convenience, the following variables provide typical NSS
32446 @defvr {Scheme Variable} %default-nss
32447 This is the default name service switch configuration, a
32448 @code{name-service-switch} object.
32451 @defvr {Scheme Variable} %mdns-host-lookup-nss
32452 This is the name service switch configuration with support for host name
32453 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
32456 The reference for name service switch configuration is given below. It
32457 is a direct mapping of the configuration file format of the C library , so
32458 please refer to the C library manual for more information (@pxref{NSS
32459 Configuration File,,, libc, The GNU C Library Reference Manual}).
32460 Compared to the configuration file format of libc NSS, it has the advantage
32461 not only of adding this warm parenthetic feel that we like, but also
32462 static checks: you will know about syntax errors and typos as soon as you
32463 run @command{guix system}.
32465 @deftp {Data Type} name-service-switch
32467 This is the data type representation the configuration of libc's name
32468 service switch (NSS). Each field below represents one of the supported
32485 The system databases handled by the NSS@. Each of these fields must be a
32486 list of @code{<name-service>} objects (see below).
32490 @deftp {Data Type} name-service
32492 This is the data type representing an actual name service and the
32493 associated lookup action.
32497 A string denoting the name service (@pxref{Services in the NSS
32498 configuration,,, libc, The GNU C Library Reference Manual}).
32500 Note that name services listed here must be visible to nscd. This is
32501 achieved by passing the @code{#:name-services} argument to
32502 @code{nscd-service} the list of packages providing the needed name
32503 services (@pxref{Base Services, @code{nscd-service}}).
32506 An action specified using the @code{lookup-specification} macro
32507 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
32508 Reference Manual}). For example:
32511 (lookup-specification (unavailable => continue)
32512 (success => return))
32517 @node Initial RAM Disk
32518 @section Initial RAM Disk
32521 @cindex initial RAM disk
32522 For bootstrapping purposes, the Linux-Libre kernel is passed an
32523 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
32524 root file system as well as an initialization script. The latter is
32525 responsible for mounting the real root file system, and for loading any
32526 kernel modules that may be needed to achieve that.
32528 The @code{initrd-modules} field of an @code{operating-system}
32529 declaration allows you to specify Linux-libre kernel modules that must
32530 be available in the initrd. In particular, this is where you would list
32531 modules needed to actually drive the hard disk where your root partition
32532 is---although the default value of @code{initrd-modules} should cover
32533 most use cases. For example, assuming you need the @code{megaraid_sas}
32534 module in addition to the default modules to be able to access your root
32535 file system, you would write:
32540 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
32543 @defvr {Scheme Variable} %base-initrd-modules
32544 This is the list of kernel modules included in the initrd by default.
32547 Furthermore, if you need lower-level customization, the @code{initrd}
32548 field of an @code{operating-system} declaration allows
32549 you to specify which initrd you would like to use. The @code{(gnu
32550 system linux-initrd)} module provides three ways to build an initrd: the
32551 high-level @code{base-initrd} procedure and the low-level
32552 @code{raw-initrd} and @code{expression->initrd} procedures.
32554 The @code{base-initrd} procedure is intended to cover most common uses.
32555 For example, if you want to add a bunch of kernel modules to be loaded
32556 at boot time, you can define the @code{initrd} field of the operating
32557 system declaration like this:
32560 (initrd (lambda (file-systems . rest)
32561 ;; Create a standard initrd but set up networking
32562 ;; with the parameters QEMU expects by default.
32563 (apply base-initrd file-systems
32564 #:qemu-networking? #t
32568 The @code{base-initrd} procedure also handles common use cases that
32569 involves using the system as a QEMU guest, or as a ``live'' system with
32570 volatile root file system.
32572 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
32573 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
32574 such as trying to guess which kernel modules and packages should be included
32575 to the initrd. An example use of @code{raw-initrd} is when a user has
32576 a custom Linux kernel configuration and default kernel modules included by
32577 @code{base-initrd} are not available.
32579 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
32580 honors several options passed on the Linux kernel command line
32581 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
32582 @code{-append} option of QEMU), notably:
32585 @item --load=@var{boot}
32586 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
32587 program, once it has mounted the root file system.
32589 Guix uses this option to yield control to a boot program that runs the
32590 service activation programs and then spawns the GNU@tie{}Shepherd, the
32591 initialization system.
32593 @item --root=@var{root}
32594 Mount @var{root} as the root file system. @var{root} can be a device
32595 name like @code{/dev/sda1}, a file system label, or a file system UUID.
32596 When unspecified, the device name from the root file system of the
32597 operating system declaration is used.
32599 @item --system=@var{system}
32600 Have @file{/run/booted-system} and @file{/run/current-system} point to
32603 @item modprobe.blacklist=@var{modules}@dots{}
32604 @cindex module, black-listing
32605 @cindex black list, of kernel modules
32606 Instruct the initial RAM disk as well as the @command{modprobe} command
32607 (from the kmod package) to refuse to load @var{modules}. @var{modules}
32608 must be a comma-separated list of module names---e.g.,
32609 @code{usbkbd,9pnet}.
32612 Start a read-eval-print loop (REPL) from the initial RAM disk before it
32613 tries to load kernel modules and to mount the root file system. Our
32614 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
32615 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
32616 Manual}, for more information on Guile's REPL.
32620 Now that you know all the features that initial RAM disks produced by
32621 @code{base-initrd} and @code{raw-initrd} provide,
32622 here is how to use it and customize it further.
32625 @cindex initial RAM disk
32626 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
32627 [#:linux-modules '()] [#:mapped-devices '()] @
32628 [#:keyboard-layout #f] @
32629 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
32630 Return a derivation that builds a raw initrd. @var{file-systems} is
32631 a list of file systems to be mounted by the initrd, possibly in addition to
32632 the root file system specified on the kernel command line via @option{--root}.
32633 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
32634 @var{mapped-devices} is a list of device mappings to realize before
32635 @var{file-systems} are mounted (@pxref{Mapped Devices}).
32636 @var{helper-packages} is a list of packages to be copied in the initrd.
32638 include @code{e2fsck/static} or other packages needed by the initrd to check
32639 the root file system.
32641 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
32642 the desired console keyboard layout. This is done before @var{mapped-devices}
32643 are set up and before @var{file-systems} are mounted such that, should the
32644 user need to enter a passphrase or use the REPL, this happens using the
32645 intended keyboard layout.
32647 When @var{qemu-networking?} is true, set up networking with the standard QEMU
32648 parameters. When @var{virtio?} is true, load additional modules so that the
32649 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
32651 When @var{volatile-root?} is true, the root file system is writable but any changes
32655 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
32656 [#:mapped-devices '()] [#:keyboard-layout #f] @
32657 [#:qemu-networking? #f] [#:volatile-root? #f] @
32658 [#:linux-modules '()]
32659 Return as a file-like object a generic initrd, with kernel
32660 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
32661 mounted by the initrd, possibly in addition to the root file system specified
32662 on the kernel command line via @option{--root}. @var{mapped-devices} is a list of device
32663 mappings to realize before @var{file-systems} are mounted.
32665 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
32666 the desired console keyboard layout. This is done before @var{mapped-devices}
32667 are set up and before @var{file-systems} are mounted such that, should the
32668 user need to enter a passphrase or use the REPL, this happens using the
32669 intended keyboard layout.
32671 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
32673 The initrd is automatically populated with all the kernel modules necessary
32674 for @var{file-systems} and for the given options. Additional kernel
32675 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
32676 loaded at boot time in the order in which they appear.
32679 Needless to say, the initrds we produce and use embed a
32680 statically-linked Guile, and the initialization program is a Guile
32681 program. That gives a lot of flexibility. The
32682 @code{expression->initrd} procedure builds such an initrd, given the
32683 program to run in that initrd.
32685 @deffn {Scheme Procedure} expression->initrd @var{exp} @
32686 [#:guile %guile-3.0-static-stripped] [#:name "guile-initrd"]
32687 Return as a file-like object a Linux initrd (a gzipped cpio archive)
32688 containing @var{guile} and that evaluates @var{exp}, a G-expression,
32689 upon booting. All the derivations referenced by @var{exp} are
32690 automatically copied to the initrd.
32693 @node Bootloader Configuration
32694 @section Bootloader Configuration
32697 @cindex boot loader
32699 The operating system supports multiple bootloaders. The bootloader is
32700 configured using @code{bootloader-configuration} declaration. All the
32701 fields of this structure are bootloader agnostic except for one field,
32702 @code{bootloader} that indicates the bootloader to be configured and
32705 Some of the bootloaders do not honor every field of
32706 @code{bootloader-configuration}. For instance, the extlinux
32707 bootloader does not support themes and thus ignores the @code{theme}
32710 @deftp {Data Type} bootloader-configuration
32711 The type of a bootloader configuration declaration.
32715 @item @code{bootloader}
32716 @cindex EFI, bootloader
32717 @cindex UEFI, bootloader
32718 @cindex BIOS, bootloader
32719 The bootloader to use, as a @code{bootloader} object. For now
32720 @code{grub-bootloader}, @code{grub-efi-bootloader},
32721 @code{grub-efi-netboot-bootloader}, @code{extlinux-bootloader} and
32722 @code{u-boot-bootloader} are supported.
32724 @cindex ARM, bootloaders
32725 @cindex AArch64, bootloaders
32726 Available bootloaders are described in @code{(gnu bootloader @dots{})}
32727 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
32728 of bootloaders for a wide range of ARM and AArch64 systems, using the
32729 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
32731 @vindex grub-efi-bootloader
32732 @code{grub-efi-bootloader} allows to boot on modern systems using the
32733 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
32734 use if the installation image contains a @file{/sys/firmware/efi} directory
32735 when you boot it on your system.
32737 @vindex grub-bootloader
32738 @code{grub-bootloader} allows you to boot in particular Intel-based machines
32739 in ``legacy'' BIOS mode.
32741 @vindex grub-efi-netboot-bootloader
32742 @code{grub-efi-netboot-bootloader} allows you to boot your system over network
32743 through TFTP@. In combination with an NFS root file system this allows you to
32744 build a diskless Guix system.
32746 The installation of the @code{grub-efi-netboot-bootloader} generates the content
32747 of the TFTP root directory at @code{target}
32748 (@pxref{Bootloader Configuration, @code{target}}), to be served by a TFTP server.
32749 You may want to mount your TFTP server directory onto @code{target} to move the
32750 required files to the TFTP server automatically.
32752 If you plan to use an NFS root file system as well (actually if you mount the
32753 store from an NFS share), then the TFTP server needs to serve the file
32754 @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
32755 image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
32756 initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
32757 files from the store will be accessed by GRUB through TFTP with their normal
32758 store path, for example as
32759 @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
32761 Two symlinks are created to make this possible. The first symlink is
32762 @code{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
32763 @file{../../../boot/grub/grub.cfg},
32764 where @code{target} may be @file{/boot}. In this case the link is not leaving
32765 the served TFTP root directory, but otherwise it does. The second link is
32766 @code{target}@file{/gnu/store} and points to @file{../gnu/store}. This link
32767 is leaving the served TFTP root directory.
32769 The assumption behind all this is that you have an NFS server exporting the root
32770 file system for your Guix system, and additionally a TFTP server exporting your
32771 @code{target} directory—usually @file{/boot}—from that same root file system for
32772 your Guix system. In this constellation the symlinks will work.
32774 For other constellations you will have to program your own bootloader installer,
32775 which then takes care to make necessary files from the store accessible through
32776 TFTP, for example by copying them into the TFTP root directory at @code{target}.
32778 It is important to note that symlinks pointing outside the TFTP root directory
32779 may need to be allowed in the configuration of your TFTP server. Further the
32780 store link exposes the whole store through TFTP@. Both points need to be
32781 considered carefully for security aspects.
32783 Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
32784 NFS servers, you also need a properly configured DHCP server to make the booting
32785 over netboot possible. For all this we can currently only recommend you to look
32786 for instructions about @acronym{PXE, Preboot eXecution Environment}.
32788 @item @code{target}
32789 This is a string denoting the target onto which to install the
32792 The interpretation depends on the bootloader in question. For
32793 @code{grub-bootloader}, for example, it should be a device name understood by
32794 the bootloader @command{installer} command, such as @code{/dev/sda} or
32795 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
32796 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
32797 system, usually @file{/boot/efi}. For @code{grub-efi-netboot-bootloader},
32798 @code{target} should be the mount point corresponding to the TFTP root
32799 directory of your TFTP server.
32801 @item @code{menu-entries} (default: @code{()})
32802 A possibly empty list of @code{menu-entry} objects (see below), denoting
32803 entries to appear in the bootloader menu, in addition to the current
32804 system entry and the entry pointing to previous system generations.
32806 @item @code{default-entry} (default: @code{0})
32807 The index of the default boot menu entry. Index 0 is for the entry of the
32810 @item @code{timeout} (default: @code{5})
32811 The number of seconds to wait for keyboard input before booting. Set to
32812 0 to boot immediately, and to -1 to wait indefinitely.
32814 @cindex keyboard layout, for the bootloader
32815 @item @code{keyboard-layout} (default: @code{#f})
32816 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
32817 layout, usually US@tie{}English (``qwerty'').
32819 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
32823 This option is currently ignored by bootloaders other than @code{grub} and
32827 @item @code{theme} (default: @var{#f})
32828 The bootloader theme object describing the theme to use. If no theme
32829 is provided, some bootloaders might use a default theme, that's true
32832 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
32833 The output terminals used for the bootloader boot menu, as a list of
32834 symbols. GRUB accepts the values: @code{console}, @code{serial},
32835 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
32836 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
32837 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
32838 configuration,,, grub,GNU GRUB manual}).
32840 @item @code{terminal-inputs} (default: @code{'()})
32841 The input terminals used for the bootloader boot menu, as a list of
32842 symbols. For GRUB, the default is the native platform terminal as
32843 determined at run-time. GRUB accepts the values: @code{console},
32844 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
32845 @code{usb_keyboard}. This field corresponds to the GRUB variable
32846 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
32849 @item @code{serial-unit} (default: @code{#f})
32850 The serial unit used by the bootloader, as an integer from 0 to 3.
32851 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
32852 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
32854 @item @code{serial-speed} (default: @code{#f})
32855 The speed of the serial interface, as an integer. For GRUB, the
32856 default value is chosen at run-time; currently GRUB chooses
32857 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
32864 Should you want to list additional boot menu entries @i{via} the
32865 @code{menu-entries} field above, you will need to create them with the
32866 @code{menu-entry} form. For example, imagine you want to be able to
32867 boot another distro (hard to imagine!), you can define a menu entry
32872 (label "The Other Distro")
32873 (linux "/boot/old/vmlinux-2.6.32")
32874 (linux-arguments '("root=/dev/sda2"))
32875 (initrd "/boot/old/initrd"))
32880 @deftp {Data Type} menu-entry
32881 The type of an entry in the bootloader menu.
32886 The label to show in the menu---e.g., @code{"GNU"}.
32888 @item @code{linux} (default: @code{#f})
32889 The Linux kernel image to boot, for example:
32892 (file-append linux-libre "/bzImage")
32895 For GRUB, it is also possible to specify a device explicitly in the
32896 file path using GRUB's device naming convention (@pxref{Naming
32897 convention,,, grub, GNU GRUB manual}), for example:
32900 "(hd0,msdos1)/boot/vmlinuz"
32903 If the device is specified explicitly as above, then the @code{device}
32904 field is ignored entirely.
32906 @item @code{linux-arguments} (default: @code{()})
32907 The list of extra Linux kernel command-line arguments---e.g.,
32908 @code{("console=ttyS0")}.
32910 @item @code{initrd} (default: @code{#f})
32911 A G-Expression or string denoting the file name of the initial RAM disk
32912 to use (@pxref{G-Expressions}).
32914 @item @code{device} (default: @code{#f})
32915 The device where the kernel and initrd are to be found---i.e., for GRUB,
32916 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
32918 This may be a file system label (a string), a file system UUID (a
32919 bytevector, @pxref{File Systems}), or @code{#f}, in which case
32920 the bootloader will search the device containing the file specified by
32921 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
32922 must @emph{not} be an OS device name such as @file{/dev/sda1}.
32924 @item @code{multiboot-kernel} (default: @code{#f})
32925 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
32926 manual}). When this field is set, a Multiboot menu-entry is generated.
32930 (file-append mach "/boot/gnumach")
32933 @item @code{multiboot-arguments} (default: @code{()})
32934 The list of extra command-line arguments for the multiboot-kernel.
32936 @item @code{multiboot-modules} (default: @code{()})
32937 The list of commands for loading Multiboot modules. For example:
32940 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
32942 (list (file-append libc "/lib/ld.so.1") "exec"
32952 @c FIXME: Write documentation once it's stable.
32953 For now only GRUB has theme support. GRUB themes are created using
32954 the @code{grub-theme} form, which is not fully documented yet.
32956 @deftp {Data Type} grub-theme
32957 Data type representing the configuration of the GRUB theme.
32960 @item @code{gfxmode} (default: @code{'("auto")})
32961 The GRUB @code{gfxmode} to set (a list of screen resolution strings,
32962 @pxref{gfxmode,,, grub, GNU GRUB manual}).
32966 @deffn {Scheme Procedure} grub-theme
32967 Return the default GRUB theme used by the operating system if no
32968 @code{theme} field is specified in @code{bootloader-configuration}
32971 It comes with a fancy background image displaying the GNU and Guix
32975 For example, to override the default resolution, you may use something
32980 (bootloader-configuration
32983 (inherit (grub-theme))
32984 (gfxmode '("1024x786x32" "auto"))))))
32987 @node Invoking guix system
32988 @section Invoking @code{guix system}
32990 Once you have written an operating system declaration as seen in the
32991 previous section, it can be @dfn{instantiated} using the @command{guix
32992 system} command. The synopsis is:
32995 guix system @var{options}@dots{} @var{action} @var{file}
32998 @var{file} must be the name of a file containing an
32999 @code{operating-system} declaration. @var{action} specifies how the
33000 operating system is instantiated. Currently the following values are
33005 Display available service type definitions that match the given regular
33006 expressions, sorted by relevance:
33012 $ guix system search console
33013 name: console-fonts
33014 location: gnu/services/base.scm:806:2
33015 extends: shepherd-root
33016 description: Install the given fonts on the specified ttys (fonts are per
33017 + virtual console on GNU/Linux). The value of this service is a list of
33018 + tty/font pairs. The font can be the name of a font provided by the `kbd'
33019 + package or any valid argument to `setfont', as in this example:
33021 + '(("tty1" . "LatGrkCyr-8x16")
33022 + ("tty2" . (file-append
33024 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
33025 + ("tty3" . (file-append
33027 + "/share/consolefonts/ter-132n"))) ; for HDPI
33031 location: gnu/services/base.scm:1190:2
33032 extends: shepherd-root
33033 description: Provide console login using the `mingetty' program.
33037 location: gnu/services/base.scm:860:2
33039 description: Provide a console log-in service as specified by its
33040 + configuration value, a `login-configuration' object.
33046 As for @command{guix package --search}, the result is written in
33047 @code{recutils} format, which makes it easy to filter the output
33048 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
33051 Build the operating system described in @var{file}, activate it, and
33052 switch to it@footnote{This action (and the related actions
33053 @code{switch-generation} and @code{roll-back}) are usable only on
33054 systems already running Guix System.}.
33057 @c The paragraph below refers to the problem discussed at
33058 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
33059 It is highly recommended to run @command{guix pull} once before you run
33060 @command{guix system reconfigure} for the first time (@pxref{Invoking
33061 guix pull}). Failing to do that you would see an older version of Guix
33062 once @command{reconfigure} has completed.
33065 This effects all the configuration specified in @var{file}: user
33066 accounts, system services, global package list, setuid programs, etc.
33067 The command starts system services specified in @var{file} that are not
33068 currently running; if a service is currently running this command will
33069 arrange for it to be upgraded the next time it is stopped (e.g.@: by
33070 @code{herd stop X} or @code{herd restart X}).
33072 This command creates a new generation whose number is one greater than
33073 the current generation (as reported by @command{guix system
33074 list-generations}). If that generation already exists, it will be
33075 overwritten. This behavior mirrors that of @command{guix package}
33076 (@pxref{Invoking guix package}).
33078 It also adds a bootloader menu entry for the new OS configuration,
33079 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
33080 entries for older configurations to a submenu, allowing you to choose
33081 an older system generation at boot time should you need it.
33083 @cindex provenance tracking, of the operating system
33084 Upon completion, the new system is deployed under
33085 @file{/run/current-system}. This directory contains @dfn{provenance
33086 meta-data}: the list of channels in use (@pxref{Channels}) and
33087 @var{file} itself, when available. You can view it by running:
33090 guix system describe
33093 This information is useful should you later want to inspect how this
33094 particular generation was built. In fact, assuming @var{file} is
33095 self-contained, you can later rebuild generation @var{n} of your
33096 operating system with:
33099 guix time-machine \
33100 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
33101 system reconfigure \
33102 /var/guix/profiles/system-@var{n}-link/configuration.scm
33105 You can think of it as some sort of built-in version control! Your
33106 system is not just a binary artifact: @emph{it carries its own source}.
33107 @xref{Service Reference, @code{provenance-service-type}}, for more
33108 information on provenance tracking.
33110 By default, @command{reconfigure} @emph{prevents you from downgrading
33111 your system}, which could (re)introduce security vulnerabilities and
33112 also cause problems with ``stateful'' services such as database
33113 management systems. You can override that behavior by passing
33114 @option{--allow-downgrades}.
33116 @item switch-generation
33117 @cindex generations
33118 Switch to an existing system generation. This action atomically
33119 switches the system profile to the specified system generation. It
33120 also rearranges the system's existing bootloader menu entries. It
33121 makes the menu entry for the specified system generation the default,
33122 and it moves the entries for the other generations to a submenu, if
33123 supported by the bootloader being used. The next time the system
33124 boots, it will use the specified system generation.
33126 The bootloader itself is not being reinstalled when using this
33127 command. Thus, the installed bootloader is used with an updated
33128 configuration file.
33130 The target generation can be specified explicitly by its generation
33131 number. For example, the following invocation would switch to system
33135 guix system switch-generation 7
33138 The target generation can also be specified relative to the current
33139 generation with the form @code{+N} or @code{-N}, where @code{+3} means
33140 ``3 generations ahead of the current generation,'' and @code{-1} means
33141 ``1 generation prior to the current generation.'' When specifying a
33142 negative value such as @code{-1}, you must precede it with @code{--} to
33143 prevent it from being parsed as an option. For example:
33146 guix system switch-generation -- -1
33149 Currently, the effect of invoking this action is @emph{only} to switch
33150 the system profile to an existing generation and rearrange the
33151 bootloader menu entries. To actually start using the target system
33152 generation, you must reboot after running this action. In the future,
33153 it will be updated to do the same things as @command{reconfigure},
33154 like activating and deactivating services.
33156 This action will fail if the specified generation does not exist.
33159 @cindex rolling back
33160 Switch to the preceding system generation. The next time the system
33161 boots, it will use the preceding system generation. This is the inverse
33162 of @command{reconfigure}, and it is exactly the same as invoking
33163 @command{switch-generation} with an argument of @code{-1}.
33165 Currently, as with @command{switch-generation}, you must reboot after
33166 running this action to actually start using the preceding system
33169 @item delete-generations
33170 @cindex deleting system generations
33171 @cindex saving space
33172 Delete system generations, making them candidates for garbage collection
33173 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
33176 This works in the same way as @samp{guix package --delete-generations}
33177 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
33178 arguments, all system generations but the current one are deleted:
33181 guix system delete-generations
33184 You can also select the generations you want to delete. The example below
33185 deletes all the system generations that are more than two month old:
33188 guix system delete-generations 2m
33191 Running this command automatically reinstalls the bootloader with an updated
33192 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
33193 longer lists the generations that have been deleted.
33196 Build the derivation of the operating system, which includes all the
33197 configuration files and programs needed to boot and run the system.
33198 This action does not actually install anything.
33201 Populate the given directory with all the files necessary to run the
33202 operating system specified in @var{file}. This is useful for first-time
33203 installations of Guix System. For instance:
33206 guix system init my-os-config.scm /mnt
33209 copies to @file{/mnt} all the store items required by the configuration
33210 specified in @file{my-os-config.scm}. This includes configuration
33211 files, packages, and so on. It also creates other essential files
33212 needed for the system to operate correctly---e.g., the @file{/etc},
33213 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
33215 This command also installs bootloader on the target specified in
33216 @file{my-os-config}, unless the @option{--no-bootloader} option was
33220 @cindex virtual machine
33222 @anchor{guix system vm}
33223 Build a virtual machine that contains the operating system declared in
33224 @var{file}, and return a script to run that virtual machine (VM).
33227 The @code{vm} action and others below
33228 can use KVM support in the Linux-libre kernel. Specifically, if the
33229 machine has hardware virtualization support, the corresponding
33230 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
33231 must exist and be readable and writable by the user and by the
33232 build users of the daemon (@pxref{Build Environment Setup}).
33235 Arguments given to the script are passed to QEMU as in the example
33236 below, which enables networking and requests 1@tie{}GiB of RAM for the
33240 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -nic user,model=virtio-net-pci
33243 The VM shares its store with the host system.
33245 Additional file systems can be shared between the host and the VM using
33246 the @option{--share} and @option{--expose} command-line options: the former
33247 specifies a directory to be shared with write access, while the latter
33248 provides read-only access to the shared directory.
33250 The example below creates a VM in which the user's home directory is
33251 accessible read-only, and where the @file{/exchange} directory is a
33252 read-write mapping of @file{$HOME/tmp} on the host:
33255 guix system vm my-config.scm \
33256 --expose=$HOME --share=$HOME/tmp=/exchange
33259 On GNU/Linux, the default is to boot directly to the kernel; this has
33260 the advantage of requiring only a very tiny root disk image since the
33261 store of the host can then be mounted.
33263 The @option{--full-boot} option forces a complete boot sequence, starting
33264 with the bootloader. This requires more disk space since a root image
33265 containing at least the kernel, initrd, and bootloader data files must
33266 be created. The @option{--image-size} option can be used to specify the
33269 @cindex System images, creation in various formats
33270 @cindex Creating system images in various formats
33272 @itemx docker-image
33273 Return a virtual machine, disk image, or Docker image of the operating
33274 system declared in @var{file} that stands alone. By default,
33275 @command{guix system} estimates the size of the image needed to store
33276 the system, but you can use the @option{--image-size} option to specify
33277 a value. Docker images are built to contain exactly what they need, so
33278 the @option{--image-size} option is ignored in the case of
33279 @code{docker-image}.
33281 @cindex image, creating disk images
33282 The @code{image} command can produce various image types. The
33283 image type can be selected using the @option{--image-type} option. It
33284 defaults to @code{efi-raw}. When its value is @code{iso9660}, the
33285 @option{--label} option can be used to specify a volume ID with
33286 @code{image}. By default, the root file system of a disk image is
33287 mounted non-volatile; the @option{--volatile} option can be provided to
33288 make it volatile instead. When using @code{image}, the bootloader
33289 installed on the generated image is taken from the provided
33290 @code{operating-system} definition. The following example demonstrates
33291 how to generate an image that uses the @code{grub-efi-bootloader}
33292 bootloader and boot it with QEMU:
33295 image=$(guix system image --image-type=qcow2 \
33296 gnu/system/examples/lightweight-desktop.tmpl)
33297 cp $image /tmp/my-image.qcow2
33298 chmod +w /tmp/my-image.qcow2
33299 qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
33300 -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
33303 When using the @code{efi-raw} image type, a raw disk image is produced;
33304 it can be copied as is to a USB stick, for instance. Assuming
33305 @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
33306 the image to it using the following command:
33309 # dd if=$(guix system image my-os.scm) of=/dev/sdc status=progress
33312 The @code{--list-image-types} command lists all the available image
33315 @cindex creating virtual machine images
33316 When using the @code{qcow2} image type, the returned image is in qcow2
33317 format, which the QEMU emulator can efficiently use. @xref{Running Guix
33318 in a VM}, for more information on how to run the image in a virtual
33319 machine. The @code{grub-bootloader} bootloader is always used
33320 independently of what is declared in the @code{operating-system} file
33321 passed as argument. This is to make it easier to work with QEMU, which
33322 uses the SeaBIOS BIOS by default, expecting a bootloader to be installed
33323 in the Master Boot Record (MBR).
33325 @cindex docker-image, creating docker images
33326 When using @code{docker-image}, a Docker image is produced. Guix builds
33327 the image from scratch, not from a pre-existing Docker base image. As a
33328 result, it contains @emph{exactly} what you define in the operating
33329 system configuration file. You can then load the image and launch a
33330 Docker container using commands like the following:
33333 image_id="$(docker load < guix-system-docker-image.tar.gz)"
33334 container_id="$(docker create $image_id)"
33335 docker start $container_id
33338 This command starts a new Docker container from the specified image. It
33339 will boot the Guix system in the usual manner, which means it will
33340 start any services you have defined in the operating system
33341 configuration. You can get an interactive shell running in the container
33342 using @command{docker exec}:
33345 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
33348 Depending on what you run in the Docker container, it
33349 may be necessary to give the container additional permissions. For
33350 example, if you intend to build software using Guix inside of the Docker
33351 container, you may need to pass the @option{--privileged} option to
33352 @code{docker create}.
33354 Last, the @option{--network} option applies to @command{guix system
33355 docker-image}: it produces an image where network is supposedly shared
33356 with the host, and thus without services like nscd or NetworkManager.
33359 Return a script to run the operating system declared in @var{file}
33360 within a container. Containers are a set of lightweight isolation
33361 mechanisms provided by the kernel Linux-libre. Containers are
33362 substantially less resource-demanding than full virtual machines since
33363 the kernel, shared objects, and other resources can be shared with the
33364 host system; this also means they provide thinner isolation.
33366 Currently, the script must be run as root in order to support more than
33367 a single user and group. The container shares its store with the host
33370 As with the @code{vm} action (@pxref{guix system vm}), additional file
33371 systems to be shared between the host and container can be specified
33372 using the @option{--share} and @option{--expose} options:
33375 guix system container my-config.scm \
33376 --expose=$HOME --share=$HOME/tmp=/exchange
33380 This option requires Linux-libre 3.19 or newer.
33385 @var{options} can contain any of the common build options (@pxref{Common
33386 Build Options}). In addition, @var{options} can contain one of the
33390 @item --expression=@var{expr}
33391 @itemx -e @var{expr}
33392 Consider the operating-system @var{expr} evaluates to.
33393 This is an alternative to specifying a file which evaluates to an
33395 This is used to generate the Guix system installer @pxref{Building the
33396 Installation Image}).
33398 @item --system=@var{system}
33399 @itemx -s @var{system}
33400 Attempt to build for @var{system} instead of the host system type.
33401 This works as per @command{guix build} (@pxref{Invoking guix build}).
33405 Return the derivation file name of the given operating system without
33408 @cindex provenance tracking, of the operating system
33409 @item --save-provenance
33410 As discussed above, @command{guix system init} and @command{guix system
33411 reconfigure} always save provenance information @i{via} a dedicated
33412 service (@pxref{Service Reference, @code{provenance-service-type}}).
33413 However, other commands don't do that by default. If you wish to, say,
33414 create a virtual machine image that contains provenance information, you
33418 guix system image -t qcow2 --save-provenance config.scm
33421 That way, the resulting image will effectively ``embed its own source''
33422 in the form of meta-data in @file{/run/current-system}. With that
33423 information, one can rebuild the image to make sure it really contains
33424 what it pretends to contain; or they could use that to derive a variant
33427 @item --image-type=@var{type}
33428 @itemx -t @var{type}
33429 For the @code{image} action, create an image with given @var{type}.
33431 When this option is omitted, @command{guix system} uses the
33432 @code{efi-raw} image type.
33434 @cindex ISO-9660 format
33435 @cindex CD image format
33436 @cindex DVD image format
33437 @option{--image-type=iso9660} produces an ISO-9660 image, suitable
33438 for burning on CDs and DVDs.
33440 @item --image-size=@var{size}
33441 For the @code{image} action, create an image of the given @var{size}.
33442 @var{size} may be a number of bytes, or it may include a unit as a
33443 suffix (@pxref{Block size, size specifications,, coreutils, GNU
33446 When this option is omitted, @command{guix system} computes an estimate
33447 of the image size as a function of the size of the system declared in
33452 For the @code{container} action, allow containers to access the host network,
33453 that is, do not create a network namespace.
33455 @item --root=@var{file}
33456 @itemx -r @var{file}
33457 Make @var{file} a symlink to the result, and register it as a garbage
33460 @item --skip-checks
33461 Skip pre-installation safety checks.
33463 By default, @command{guix system init} and @command{guix system
33464 reconfigure} perform safety checks: they make sure the file systems that
33465 appear in the @code{operating-system} declaration actually exist
33466 (@pxref{File Systems}), and that any Linux kernel modules that may be
33467 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
33468 RAM Disk}). Passing this option skips these tests altogether.
33470 @item --allow-downgrades
33471 Instruct @command{guix system reconfigure} to allow system downgrades.
33473 By default, @command{reconfigure} prevents you from downgrading your
33474 system. It achieves that by comparing the provenance info of your
33475 system (shown by @command{guix system describe}) with that of your
33476 @command{guix} command (shown by @command{guix describe}). If the
33477 commits for @command{guix} are not descendants of those used for your
33478 system, @command{guix system reconfigure} errors out. Passing
33479 @option{--allow-downgrades} allows you to bypass these checks.
33482 Make sure you understand its security implications before using
33483 @option{--allow-downgrades}.
33487 @cindex on-error strategy
33488 @cindex error strategy
33489 @item --on-error=@var{strategy}
33490 Apply @var{strategy} when an error occurs when reading @var{file}.
33491 @var{strategy} may be one of the following:
33494 @item nothing-special
33495 Report the error concisely and exit. This is the default strategy.
33498 Likewise, but also display a backtrace.
33501 Report the error and enter Guile's debugger. From there, you can run
33502 commands such as @code{,bt} to get a backtrace, @code{,locals} to
33503 display local variable values, and more generally inspect the state of the
33504 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
33505 a list of available debugging commands.
33509 Once you have built, configured, re-configured, and re-re-configured
33510 your Guix installation, you may find it useful to list the operating
33511 system generations available on disk---and that you can choose from the
33512 bootloader boot menu:
33517 Describe the current system generation: its file name, the kernel and
33518 bootloader used, etc., as well as provenance information when available.
33520 @item list-generations
33521 List a summary of each generation of the operating system available on
33522 disk, in a human-readable way. This is similar to the
33523 @option{--list-generations} option of @command{guix package}
33524 (@pxref{Invoking guix package}).
33526 Optionally, one can specify a pattern, with the same syntax that is used
33527 in @command{guix package --list-generations}, to restrict the list of
33528 generations displayed. For instance, the following command displays
33529 generations that are up to 10 days old:
33532 $ guix system list-generations 10d
33537 The @command{guix system} command has even more to offer! The following
33538 sub-commands allow you to visualize how your system services relate to
33541 @anchor{system-extension-graph}
33544 @item extension-graph
33545 Emit to standard output the @dfn{service
33546 extension graph} of the operating system defined in @var{file}
33547 (@pxref{Service Composition}, for more information on service
33548 extensions). By default the output is in Dot/Graphviz format, but you
33549 can choose a different format with @option{--graph-backend}, as with
33550 @command{guix graph} (@pxref{Invoking guix graph, @option{--backend}}):
33555 $ guix system extension-graph @var{file} | xdot -
33558 shows the extension relations among services.
33560 @anchor{system-shepherd-graph}
33561 @item shepherd-graph
33562 Emit to standard output the @dfn{dependency
33563 graph} of shepherd services of the operating system defined in
33564 @var{file}. @xref{Shepherd Services}, for more information and for an
33567 Again, the default output format is Dot/Graphviz, but you can pass
33568 @option{--graph-backend} to select a different one.
33572 @node Invoking guix deploy
33573 @section Invoking @code{guix deploy}
33575 We've already seen @code{operating-system} declarations used to manage a
33576 machine's configuration locally. Suppose you need to configure multiple
33577 machines, though---perhaps you're managing a service on the web that's
33578 comprised of several servers. @command{guix deploy} enables you to use those
33579 same @code{operating-system} declarations to manage multiple remote hosts at
33580 once as a logical ``deployment''.
33583 The functionality described in this section is still under development
33584 and is subject to change. Get in touch with us on
33585 @email{guix-devel@@gnu.org}!
33589 guix deploy @var{file}
33592 Such an invocation will deploy the machines that the code within @var{file}
33593 evaluates to. As an example, @var{file} might contain a definition like this:
33596 ;; This is a Guix deployment of a "bare bones" setup, with
33597 ;; no X11 display server, to a machine with an SSH daemon
33598 ;; listening on localhost:2222. A configuration such as this
33599 ;; may be appropriate for virtual machine with ports
33600 ;; forwarded to the host's loopback interface.
33602 (use-service-modules networking ssh)
33603 (use-package-modules bootloaders)
33607 (host-name "gnu-deployed")
33608 (timezone "Etc/UTC")
33609 (bootloader (bootloader-configuration
33610 (bootloader grub-bootloader)
33611 (target "/dev/vda")
33612 (terminal-outputs '(console))))
33613 (file-systems (cons (file-system
33615 (device "/dev/vda1")
33617 %base-file-systems))
33619 (append (list (service dhcp-client-service-type)
33620 (service openssh-service-type
33621 (openssh-configuration
33622 (permit-root-login #t)
33623 (allow-empty-passwords? #t))))
33627 (operating-system %system)
33628 (environment managed-host-environment-type)
33629 (configuration (machine-ssh-configuration
33630 (host-name "localhost")
33631 (system "x86_64-linux")
33633 (identity "./id_rsa")
33637 The file should evaluate to a list of @var{machine} objects. This example,
33638 upon being deployed, will create a new generation on the remote system
33639 realizing the @code{operating-system} declaration @code{%system}.
33640 @code{environment} and @code{configuration} specify how the machine should be
33641 provisioned---that is, how the computing resources should be created and
33642 managed. The above example does not create any resources, as a
33643 @code{'managed-host} is a machine that is already running the Guix system and
33644 available over the network. This is a particularly simple case; a more
33645 complex deployment may involve, for example, starting virtual machines through
33646 a Virtual Private Server (VPS) provider. In such a case, a different
33647 @var{environment} type would be used.
33649 Do note that you first need to generate a key pair on the coordinator machine
33650 to allow the daemon to export signed archives of files from the store
33651 (@pxref{Invoking guix archive}), though this step is automatic on Guix
33655 # guix archive --generate-key
33659 Each target machine must authorize the key of the master machine so that it
33660 accepts store items it receives from the coordinator:
33663 # guix archive --authorize < coordinator-public-key.txt
33666 @code{user}, in this example, specifies the name of the user account to log in
33667 as to perform the deployment. Its default value is @code{root}, but root
33668 login over SSH may be forbidden in some cases. To work around this,
33669 @command{guix deploy} can log in as an unprivileged user and employ
33670 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
33671 currently installed on the remote and can be invoked non-interactively as
33672 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
33673 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
33674 be accomplished with the following operating system configuration snippet:
33678 (gnu system)) ;for %sudoers-specification
33680 (define %user "username")
33685 (plain-file "sudoers"
33686 (string-append (plain-file-content %sudoers-specification)
33687 (format #f "~a ALL = NOPASSWD: ALL~%"
33692 For more information regarding the format of the @file{sudoers} file,
33693 consult @command{man sudoers}.
33695 @deftp {Data Type} machine
33696 This is the data type representing a single machine in a heterogeneous Guix
33700 @item @code{operating-system}
33701 The object of the operating system configuration to deploy.
33703 @item @code{environment}
33704 An @code{environment-type} describing how the machine should be provisioned.
33706 @item @code{configuration} (default: @code{#f})
33707 An object describing the configuration for the machine's @code{environment}.
33708 If the @code{environment} has a default configuration, @code{#f} may be used.
33709 If @code{#f} is used for an environment with no default configuration,
33710 however, an error will be thrown.
33714 @deftp {Data Type} machine-ssh-configuration
33715 This is the data type representing the SSH client parameters for a machine
33716 with an @code{environment} of @code{managed-host-environment-type}.
33719 @item @code{host-name}
33720 @item @code{build-locally?} (default: @code{#t})
33721 If false, system derivations will be built on the machine being deployed to.
33722 @item @code{system}
33723 The system type describing the architecture of the machine being deployed
33724 to---e.g., @code{"x86_64-linux"}.
33725 @item @code{authorize?} (default: @code{#t})
33726 If true, the coordinator's signing key will be added to the remote's ACL
33728 @item @code{port} (default: @code{22})
33729 @item @code{user} (default: @code{"root"})
33730 @item @code{identity} (default: @code{#f})
33731 If specified, the path to the SSH private key to use to authenticate with the
33734 @item @code{host-key} (default: @code{#f})
33735 This should be the SSH host key of the machine, which looks like this:
33738 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
33741 When @code{host-key} is @code{#f}, the server is authenticated against
33742 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
33745 @item @code{allow-downgrades?} (default: @code{#f})
33746 Whether to allow potential downgrades.
33748 Like @command{guix system reconfigure}, @command{guix deploy} compares
33749 the channel commits currently deployed on the remote host (as returned
33750 by @command{guix system describe}) to those currently in use (as
33751 returned by @command{guix describe}) to determine whether commits
33752 currently in use are descendants of those deployed. When this is not
33753 the case and @code{allow-downgrades?} is false, it raises an error.
33754 This ensures you do not accidentally downgrade remote machines.
33758 @deftp {Data Type} digital-ocean-configuration
33759 This is the data type describing the Droplet that should be created for a
33760 machine with an @code{environment} of @code{digital-ocean-environment-type}.
33763 @item @code{ssh-key}
33764 The path to the SSH private key to use to authenticate with the remote
33765 host. In the future, this field may not exist.
33767 A list of string ``tags'' that uniquely identify the machine. Must be given
33768 such that no two machines in the deployment have the same set of tags.
33769 @item @code{region}
33770 A Digital Ocean region slug, such as @code{"nyc3"}.
33772 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
33773 @item @code{enable-ipv6?}
33774 Whether or not the droplet should be created with IPv6 networking.
33778 @node Running Guix in a VM
33779 @section Running Guix in a Virtual Machine
33781 @cindex virtual machine
33782 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM
33783 image distributed at
33784 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.qcow2}.
33785 This image is a compressed image in QCOW format. You can pass it to an
33786 emulator such as @uref{https://qemu.org/, QEMU} (see below for details).
33788 This image boots the Xfce graphical environment and it contains some
33789 commonly used tools. You can install more software in the image by running
33790 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
33791 also reconfigure the system based on its initial configuration file available
33792 as @file{/run/current-system/configuration.scm} (@pxref{Using the
33793 Configuration System}).
33795 Instead of using this pre-built image, one can also build their own
33796 image using @command{guix system image} (@pxref{Invoking guix system}).
33799 If you built your own image, you must copy it out of the store
33800 (@pxref{The Store}) and give yourself permission to write to the copy
33801 before you can use it. When invoking QEMU, you must choose a system
33802 emulator that is suitable for your hardware platform. Here is a minimal
33803 QEMU invocation that will boot the result of @command{guix system
33804 image -t qcow2} on x86_64 hardware:
33807 $ qemu-system-x86_64 \
33808 -nic user,model=virtio-net-pci \
33809 -enable-kvm -m 1024 \
33810 -device virtio-blk,drive=myhd \
33811 -drive if=none,file=/tmp/qemu-image,id=myhd
33814 Here is what each of these options means:
33817 @item qemu-system-x86_64
33818 This specifies the hardware platform to emulate. This should match the
33821 @item -nic user,model=virtio-net-pci
33822 Enable the unprivileged user-mode network stack. The guest OS can
33823 access the host but not vice versa. This is the simplest way to get the
33824 guest OS online. @code{model} specifies which network device to emulate:
33825 @code{virtio-net-pci} is a special device made for virtualized operating
33826 systems and recommended for most uses. Assuming your hardware platform is
33827 x86_64, you can get a list of available NIC models by running
33828 @command{qemu-system-x86_64 -nic model=help}.
33831 If your system has hardware virtualization extensions, enabling the
33832 virtual machine support (KVM) of the Linux kernel will make things run
33835 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
33837 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
33838 which may be insufficient for some operations.
33840 @item -device virtio-blk,drive=myhd
33841 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
33842 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
33843 better performance than if it were emulating a complete disk drive. See the
33844 QEMU and KVM documentation for more info.
33846 @item -drive if=none,file=/tmp/qemu-image,id=myhd
33847 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
33848 store of the ``myhd'' drive.
33851 The default @command{run-vm.sh} script that is returned by an invocation of
33852 @command{guix system vm} does not add a @command{-nic user} flag by default.
33853 To get network access from within the vm add the @code{(dhcp-client-service)}
33854 to your system definition and start the VM using
33855 @command{$(guix system vm config.scm) -nic user}. An important caveat of using
33856 @command{-nic user} for networking is that @command{ping} will not work, because
33857 it uses the ICMP protocol. You'll have to use a different command to check for
33858 network connectivity, for example @command{guix download}.
33860 @subsection Connecting Through SSH
33864 To enable SSH inside a VM you need to add an SSH server like
33865 @code{openssh-service-type} to your VM (@pxref{Networking Services,
33866 @code{openssh-service-type}}). In addition you need to forward the SSH port,
33867 22 by default, to the host. You can do this with
33870 $(guix system vm config.scm) -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
33873 To connect to the VM you can run
33876 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022 localhost
33879 The @command{-p} tells @command{ssh} the port you want to connect to.
33880 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
33881 every time you modify your @command{config.scm} file and the
33882 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
33883 connection to an unknown host every time you connect.
33886 If you find the above @samp{hostfwd} example not to be working (e.g.,
33887 your SSH client hangs attempting to connect to the mapped port of your
33888 VM), make sure that your Guix System VM has networking support, such as
33889 by using the @code{dhcp-client-service-type} service type.
33892 @subsection Using @command{virt-viewer} with Spice
33894 As an alternative to the default @command{qemu} graphical client you can
33895 use the @command{remote-viewer} from the @command{virt-viewer} package. To
33896 connect pass the @command{-spice port=5930,disable-ticketing} flag to
33897 @command{qemu}. See previous section for further information on how to do this.
33899 Spice also allows you to do some nice stuff like share your clipboard with your
33900 VM@. To enable that you'll also have to pass the following flags to @command{qemu}:
33903 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
33904 -chardev spicevmc,name=vdagent,id=vdagent
33905 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
33906 name=com.redhat.spice.0
33909 You'll also need to add the @code{(spice-vdagent-service)} to your
33910 system definition (@pxref{Miscellaneous Services, Spice service}).
33912 @node Defining Services
33913 @section Defining Services
33915 The previous sections show the available services and how one can combine
33916 them in an @code{operating-system} declaration. But how do we define
33917 them in the first place? And what is a service anyway?
33920 * Service Composition:: The model for composing services.
33921 * Service Types and Services:: Types and services.
33922 * Service Reference:: API reference.
33923 * Shepherd Services:: A particular type of service.
33926 @node Service Composition
33927 @subsection Service Composition
33931 Here we define a @dfn{service} as, broadly, something that extends the
33932 functionality of the operating system. Often a service is a process---a
33933 @dfn{daemon}---started when the system boots: a secure shell server, a
33934 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
33935 whose execution can be triggered by another daemon---e.g., an FTP server
33936 started by @command{inetd} or a D-Bus service activated by
33937 @command{dbus-daemon}. Occasionally, a service does not map to a
33938 daemon. For instance, the ``account'' service collects user accounts
33939 and makes sure they exist when the system runs; the ``udev'' service
33940 collects device management rules and makes them available to the eudev
33941 daemon; the @file{/etc} service populates the @file{/etc} directory
33944 @cindex service extensions
33945 Guix system services are connected by @dfn{extensions}. For instance, the
33946 secure shell service @emph{extends} the Shepherd---the
33947 initialization system, running as PID@tie{}1---by giving it the command
33948 lines to start and stop the secure shell daemon (@pxref{Networking
33949 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
33950 service by passing it its @file{.service} specification, and extends the
33951 udev service by passing it device management rules (@pxref{Desktop
33952 Services, @code{upower-service}}); the Guix daemon service extends the
33953 Shepherd by passing it the command lines to start and stop the daemon,
33954 and extends the account service by passing it a list of required build
33955 user accounts (@pxref{Base Services}).
33957 All in all, services and their ``extends'' relations form a directed
33958 acyclic graph (DAG). If we represent services as boxes and extensions
33959 as arrows, a typical system might provide something like this:
33961 @image{images/service-graph,,5in,Typical service extension graph.}
33963 @cindex system service
33964 At the bottom, we see the @dfn{system service}, which produces the
33965 directory containing everything to run and boot the system, as returned
33966 by the @command{guix system build} command. @xref{Service Reference},
33967 to learn about the other service types shown here.
33968 @xref{system-extension-graph, the @command{guix system extension-graph}
33969 command}, for information on how to generate this representation for a
33970 particular operating system definition.
33972 @cindex service types
33973 Technically, developers can define @dfn{service types} to express these
33974 relations. There can be any number of services of a given type on the
33975 system---for instance, a system running two instances of the GNU secure
33976 shell server (lsh) has two instances of @code{lsh-service-type}, with
33977 different parameters.
33979 The following section describes the programming interface for service
33980 types and services.
33982 @node Service Types and Services
33983 @subsection Service Types and Services
33985 A @dfn{service type} is a node in the DAG described above. Let us start
33986 with a simple example, the service type for the Guix build daemon
33987 (@pxref{Invoking guix-daemon}):
33990 (define guix-service-type
33994 (list (service-extension shepherd-root-service-type guix-shepherd-service)
33995 (service-extension account-service-type guix-accounts)
33996 (service-extension activation-service-type guix-activation)))
33997 (default-value (guix-configuration))))
34001 It defines three things:
34005 A name, whose sole purpose is to make inspection and debugging easier.
34008 A list of @dfn{service extensions}, where each extension designates the
34009 target service type and a procedure that, given the parameters of the
34010 service, returns a list of objects to extend the service of that type.
34012 Every service type has at least one service extension. The only
34013 exception is the @dfn{boot service type}, which is the ultimate service.
34016 Optionally, a default value for instances of this type.
34019 In this example, @code{guix-service-type} extends three services:
34022 @item shepherd-root-service-type
34023 The @code{guix-shepherd-service} procedure defines how the Shepherd
34024 service is extended. Namely, it returns a @code{<shepherd-service>}
34025 object that defines how @command{guix-daemon} is started and stopped
34026 (@pxref{Shepherd Services}).
34028 @item account-service-type
34029 This extension for this service is computed by @code{guix-accounts},
34030 which returns a list of @code{user-group} and @code{user-account}
34031 objects representing the build user accounts (@pxref{Invoking
34034 @item activation-service-type
34035 Here @code{guix-activation} is a procedure that returns a gexp, which is
34036 a code snippet to run at ``activation time''---e.g., when the service is
34040 A service of this type is instantiated like this:
34043 (service guix-service-type
34044 (guix-configuration
34046 (extra-options '("--gc-keep-derivations"))))
34049 The second argument to the @code{service} form is a value representing
34050 the parameters of this specific service instance.
34051 @xref{guix-configuration-type, @code{guix-configuration}}, for
34052 information about the @code{guix-configuration} data type. When the
34053 value is omitted, the default value specified by
34054 @code{guix-service-type} is used:
34057 (service guix-service-type)
34060 @code{guix-service-type} is quite simple because it extends other
34061 services but is not extensible itself.
34063 @c @subsubsubsection Extensible Service Types
34065 The service type for an @emph{extensible} service looks like this:
34068 (define udev-service-type
34069 (service-type (name 'udev)
34071 (list (service-extension shepherd-root-service-type
34072 udev-shepherd-service)))
34074 (compose concatenate) ;concatenate the list of rules
34075 (extend (lambda (config rules)
34077 (($ <udev-configuration> udev initial-rules)
34078 (udev-configuration
34079 (udev udev) ;the udev package to use
34080 (rules (append initial-rules rules)))))))))
34083 This is the service type for the
34084 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
34085 management daemon}. Compared to the previous example, in addition to an
34086 extension of @code{shepherd-root-service-type}, we see two new fields:
34090 This is the procedure to @dfn{compose} the list of extensions to
34091 services of this type.
34093 Services can extend the udev service by passing it lists of rules; we
34094 compose those extensions simply by concatenating them.
34097 This procedure defines how the value of the service is @dfn{extended} with
34098 the composition of the extensions.
34100 Udev extensions are composed into a list of rules, but the udev service
34101 value is itself a @code{<udev-configuration>} record. So here, we
34102 extend that record by appending the list of rules it contains to the
34103 list of contributed rules.
34106 This is a string giving an overview of the service type. The string can
34107 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
34108 @command{guix system search} command searches these strings and displays
34109 them (@pxref{Invoking guix system}).
34112 There can be only one instance of an extensible service type such as
34113 @code{udev-service-type}. If there were more, the
34114 @code{service-extension} specifications would be ambiguous.
34116 Still here? The next section provides a reference of the programming
34117 interface for services.
34119 @node Service Reference
34120 @subsection Service Reference
34122 We have seen an overview of service types (@pxref{Service Types and
34123 Services}). This section provides a reference on how to manipulate
34124 services and service types. This interface is provided by the
34125 @code{(gnu services)} module.
34127 @deffn {Scheme Procedure} service @var{type} [@var{value}]
34128 Return a new service of @var{type}, a @code{<service-type>} object (see
34129 below). @var{value} can be any object; it represents the parameters of
34130 this particular service instance.
34132 When @var{value} is omitted, the default value specified by @var{type}
34133 is used; if @var{type} does not specify a default value, an error is
34136 For instance, this:
34139 (service openssh-service-type)
34143 is equivalent to this:
34146 (service openssh-service-type
34147 (openssh-configuration))
34150 In both cases the result is an instance of @code{openssh-service-type}
34151 with the default configuration.
34154 @deffn {Scheme Procedure} service? @var{obj}
34155 Return true if @var{obj} is a service.
34158 @deffn {Scheme Procedure} service-kind @var{service}
34159 Return the type of @var{service}---i.e., a @code{<service-type>} object.
34162 @deffn {Scheme Procedure} service-value @var{service}
34163 Return the value associated with @var{service}. It represents its
34167 Here is an example of how a service is created and manipulated:
34171 (service nginx-service-type
34172 (nginx-configuration
34174 (log-directory log-directory)
34175 (run-directory run-directory)
34176 (file config-file))))
34181 (eq? (service-kind s) nginx-service-type)
34185 The @code{modify-services} form provides a handy way to change the
34186 parameters of some of the services of a list such as
34187 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
34188 evaluates to a list of services. Of course, you could always use
34189 standard list combinators such as @code{map} and @code{fold} to do that
34190 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
34191 @code{modify-services} simply provides a more concise form for this
34194 @deffn {Scheme Syntax} modify-services @var{services} @
34195 (@var{type} @var{variable} => @var{body}) @dots{}
34197 Modify the services listed in @var{services} according to the given
34198 clauses. Each clause has the form:
34201 (@var{type} @var{variable} => @var{body})
34204 where @var{type} is a service type---e.g.,
34205 @code{guix-service-type}---and @var{variable} is an identifier that is
34206 bound within the @var{body} to the service parameters---e.g., a
34207 @code{guix-configuration} instance---of the original service of that
34210 The @var{body} should evaluate to the new service parameters, which will
34211 be used to configure the new service. This new service will replace the
34212 original in the resulting list. Because a service's service parameters
34213 are created using @code{define-record-type*}, you can write a succinct
34214 @var{body} that evaluates to the new service parameters by using the
34215 @code{inherit} feature that @code{define-record-type*} provides.
34217 @xref{Using the Configuration System}, for example usage.
34221 Next comes the programming interface for service types. This is
34222 something you want to know when writing new service definitions, but not
34223 necessarily when simply looking for ways to customize your
34224 @code{operating-system} declaration.
34226 @deftp {Data Type} service-type
34227 @cindex service type
34228 This is the representation of a @dfn{service type} (@pxref{Service Types
34233 This is a symbol, used only to simplify inspection and debugging.
34235 @item @code{extensions}
34236 A non-empty list of @code{<service-extension>} objects (see below).
34238 @item @code{compose} (default: @code{#f})
34239 If this is @code{#f}, then the service type denotes services that cannot
34240 be extended---i.e., services that do not receive ``values'' from other
34243 Otherwise, it must be a one-argument procedure. The procedure is called
34244 by @code{fold-services} and is passed a list of values collected from
34245 extensions. It may return any single value.
34247 @item @code{extend} (default: @code{#f})
34248 If this is @code{#f}, services of this type cannot be extended.
34250 Otherwise, it must be a two-argument procedure: @code{fold-services}
34251 calls it, passing it the initial value of the service as the first
34252 argument and the result of applying @code{compose} to the extension
34253 values as the second argument. It must return a value that is a valid
34254 parameter value for the service instance.
34256 @item @code{description}
34257 This is a string, possibly using Texinfo markup, describing in a couple
34258 of sentences what the service is about. This string allows users to
34259 find about the service through @command{guix system search}
34260 (@pxref{Invoking guix system}).
34262 @item @code{default-value} (default: @code{&no-default-value})
34263 The default value associated for instances of this service type. This
34264 allows users to use the @code{service} form without its second argument:
34267 (service @var{type})
34270 The returned service in this case has the default value specified by
34274 @xref{Service Types and Services}, for examples.
34277 @deffn {Scheme Procedure} service-extension @var{target-type} @
34279 Return a new extension for services of type @var{target-type}.
34280 @var{compute} must be a one-argument procedure: @code{fold-services}
34281 calls it, passing it the value associated with the service that provides
34282 the extension; it must return a valid value for the target service.
34285 @deffn {Scheme Procedure} service-extension? @var{obj}
34286 Return true if @var{obj} is a service extension.
34289 Occasionally, you might want to simply extend an existing service. This
34290 involves creating a new service type and specifying the extension of
34291 interest, which can be verbose; the @code{simple-service} procedure
34292 provides a shorthand for this.
34294 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
34295 Return a service that extends @var{target} with @var{value}. This works
34296 by creating a singleton service type @var{name}, of which the returned
34297 service is an instance.
34299 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
34303 (simple-service 'my-mcron-job mcron-service-type
34304 #~(job '(next-hour (3)) "guix gc -F 2G"))
34308 At the core of the service abstraction lies the @code{fold-services}
34309 procedure, which is responsible for ``compiling'' a list of services
34310 down to a single directory that contains everything needed to boot and
34311 run the system---the directory shown by the @command{guix system build}
34312 command (@pxref{Invoking guix system}). In essence, it propagates
34313 service extensions down the service graph, updating each node parameters
34314 on the way, until it reaches the root node.
34316 @deffn {Scheme Procedure} fold-services @var{services} @
34317 [#:target-type @var{system-service-type}]
34318 Fold @var{services} by propagating their extensions down to the root of
34319 type @var{target-type}; return the root service adjusted accordingly.
34322 Lastly, the @code{(gnu services)} module also defines several essential
34323 service types, some of which are listed below.
34325 @defvr {Scheme Variable} system-service-type
34326 This is the root of the service graph. It produces the system directory
34327 as returned by the @command{guix system build} command.
34330 @defvr {Scheme Variable} boot-service-type
34331 The type of the ``boot service'', which produces the @dfn{boot script}.
34332 The boot script is what the initial RAM disk runs when booting.
34335 @defvr {Scheme Variable} etc-service-type
34336 The type of the @file{/etc} service. This service is used to create
34337 files under @file{/etc} and can be extended by
34338 passing it name/file tuples such as:
34341 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
34344 In this example, the effect would be to add an @file{/etc/issue} file
34345 pointing to the given file.
34348 @defvr {Scheme Variable} setuid-program-service-type
34349 Type for the ``setuid-program service''. This service collects lists of
34350 executable file names, passed as gexps, and adds them to the set of
34351 setuid-root programs on the system (@pxref{Setuid Programs}).
34354 @defvr {Scheme Variable} profile-service-type
34355 Type of the service that populates the @dfn{system profile}---i.e., the
34356 programs under @file{/run/current-system/profile}. Other services can
34357 extend it by passing it lists of packages to add to the system profile.
34360 @cindex provenance tracking, of the operating system
34361 @anchor{provenance-service-type}
34362 @defvr {Scheme Variable} provenance-service-type
34363 This is the type of the service that records @dfn{provenance meta-data}
34364 in the system itself. It creates several files under
34365 @file{/run/current-system}:
34369 This is a ``channel file'' that can be passed to @command{guix pull -C}
34370 or @command{guix time-machine -C}, and which describes the channels used
34371 to build the system, if that information was available
34372 (@pxref{Channels}).
34374 @item configuration.scm
34375 This is the file that was passed as the value for this
34376 @code{provenance-service-type} service. By default, @command{guix
34377 system reconfigure} automatically passes the OS configuration file it
34378 received on the command line.
34381 This contains the same information as the two other files but in a
34382 format that is more readily processable.
34385 In general, these two pieces of information (channels and configuration
34386 file) are enough to reproduce the operating system ``from source''.
34389 This information is necessary to rebuild your operating system, but it
34390 is not always sufficient. In particular, @file{configuration.scm}
34391 itself is insufficient if it is not self-contained---if it refers to
34392 external Guile modules or to extra files. If you want
34393 @file{configuration.scm} to be self-contained, we recommend that modules
34394 or files it refers to be part of a channel.
34396 Besides, provenance meta-data is ``silent'' in the sense that it does
34397 not change the bits contained in your system, @emph{except for the
34398 meta-data bits themselves}. Two different OS configurations or sets of
34399 channels can lead to the same system, bit-for-bit; when
34400 @code{provenance-service-type} is used, these two systems will have
34401 different meta-data and thus different store file names, which makes
34402 comparison less trivial.
34405 This service is automatically added to your operating system
34406 configuration when you use @command{guix system reconfigure},
34407 @command{guix system init}, or @command{guix deploy}.
34410 @defvr {Scheme Variable} linux-loadable-module-service-type
34411 Type of the service that collects lists of packages containing
34412 kernel-loadable modules, and adds them to the set of kernel-loadable
34415 This service type is intended to be extended by other service types,
34419 (simple-service 'installing-module
34420 linux-loadable-module-service-type
34421 (list module-to-install-1
34422 module-to-install-2))
34425 This does not actually load modules at bootup, only adds it to the
34426 kernel profile so that it @emph{can} be loaded by other means.
34429 @node Shepherd Services
34430 @subsection Shepherd Services
34432 @cindex shepherd services
34434 @cindex init system
34435 The @code{(gnu services shepherd)} module provides a way to define
34436 services managed by the GNU@tie{}Shepherd, which is the
34437 initialization system---the first process that is started when the
34438 system boots, also known as PID@tie{}1
34439 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
34441 Services in the Shepherd can depend on each other. For instance, the
34442 SSH daemon may need to be started after the syslog daemon has been
34443 started, which in turn can only happen once all the file systems have
34444 been mounted. The simple operating system defined earlier (@pxref{Using
34445 the Configuration System}) results in a service graph like this:
34447 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
34449 You can actually generate such a graph for any operating system
34450 definition using the @command{guix system shepherd-graph} command
34451 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
34453 The @code{%shepherd-root-service} is a service object representing
34454 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
34455 by passing it lists of @code{<shepherd-service>} objects.
34457 @deftp {Data Type} shepherd-service
34458 The data type representing a service managed by the Shepherd.
34461 @item @code{provision}
34462 This is a list of symbols denoting what the service provides.
34464 These are the names that may be passed to @command{herd start},
34465 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
34466 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
34467 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
34469 @item @code{requirement} (default: @code{'()})
34470 List of symbols denoting the Shepherd services this one depends on.
34472 @cindex one-shot services, for the Shepherd
34473 @item @code{one-shot?} (default: @code{#f})
34474 Whether this service is @dfn{one-shot}. One-shot services stop immediately
34475 after their @code{start} action has completed. @xref{Slots of services,,,
34476 shepherd, The GNU Shepherd Manual}, for more info.
34478 @item @code{respawn?} (default: @code{#t})
34479 Whether to restart the service when it stops, for instance when the
34480 underlying process dies.
34483 @itemx @code{stop} (default: @code{#~(const #f)})
34484 The @code{start} and @code{stop} fields refer to the Shepherd's
34485 facilities to start and stop processes (@pxref{Service De- and
34486 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
34487 G-expressions that get expanded in the Shepherd configuration file
34488 (@pxref{G-Expressions}).
34490 @item @code{actions} (default: @code{'()})
34491 @cindex actions, of Shepherd services
34492 This is a list of @code{shepherd-action} objects (see below) defining
34493 @dfn{actions} supported by the service, in addition to the standard
34494 @code{start} and @code{stop} actions. Actions listed here become available as
34495 @command{herd} sub-commands:
34498 herd @var{action} @var{service} [@var{arguments}@dots{}]
34501 @item @code{auto-start?} (default: @code{#t})
34502 Whether this service should be started automatically by the Shepherd. If it
34503 is @code{#f} the service has to be started manually with @code{herd start}.
34505 @item @code{documentation}
34506 A documentation string, as shown when running:
34509 herd doc @var{service-name}
34512 where @var{service-name} is one of the symbols in @code{provision}
34513 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
34515 @item @code{modules} (default: @code{%default-modules})
34516 This is the list of modules that must be in scope when @code{start} and
34517 @code{stop} are evaluated.
34522 The example below defines a Shepherd service that spawns
34523 @command{syslogd}, the system logger from the GNU Networking Utilities
34524 (@pxref{syslogd invocation, @command{syslogd},, inetutils, GNU
34528 (let ((config (plain-file "syslogd.conf" "@dots{}")))
34530 (documentation "Run the syslog daemon (syslogd).")
34531 (provision '(syslogd))
34532 (requirement '(user-processes))
34533 (start #~(make-forkexec-constructor
34534 (list #$(file-append inetutils "/libexec/syslogd")
34535 "--rcfile" #$config)
34536 #:pid-file "/var/run/syslog.pid"))
34537 (stop #~(make-kill-destructor))))
34540 Key elements in this example are the @code{start} and @code{stop}
34541 fields: they are @dfn{staged} code snippets that use the
34542 @code{make-forkexec-constructor} procedure provided by the Shepherd and
34543 its dual, @code{make-kill-destructor} (@pxref{Service De- and
34544 Constructors,,, shepherd, The GNU Shepherd Manual}). The @code{start}
34545 field will have @command{shepherd} spawn @command{syslogd} with the
34546 given option; note that we pass @code{config} after @option{--rcfile},
34547 which is a configuration file declared above (contents of this file are
34548 omitted). Likewise, the @code{stop} field tells how this service is to
34549 be stopped; in this case, it is stopped by making the @code{kill} system
34550 call on its PID@. Code staging is achieved using G-expressions:
34551 @code{#~} stages code, while @code{#$} ``escapes'' back to host code
34552 (@pxref{G-Expressions}).
34554 @deftp {Data Type} shepherd-action
34555 This is the data type that defines additional actions implemented by a
34556 Shepherd service (see above).
34560 Symbol naming the action.
34562 @item documentation
34563 This is a documentation string for the action. It can be viewed by running:
34566 herd doc @var{service} action @var{action}
34570 This should be a gexp that evaluates to a procedure of at least one argument,
34571 which is the ``running value'' of the service (@pxref{Slots of services,,,
34572 shepherd, The GNU Shepherd Manual}).
34575 The following example defines an action called @code{say-hello} that kindly
34581 (documentation "Say hi!")
34582 (procedure #~(lambda (running . args)
34583 (format #t "Hello, friend! arguments: ~s\n"
34588 Assuming this action is added to the @code{example} service, then you can do:
34591 # herd say-hello example
34592 Hello, friend! arguments: ()
34593 # herd say-hello example a b c
34594 Hello, friend! arguments: ("a" "b" "c")
34597 This, as you can see, is a fairly sophisticated way to say hello.
34598 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
34602 @defvr {Scheme Variable} shepherd-root-service-type
34603 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
34605 This is the service type that extensions target when they want to create
34606 shepherd services (@pxref{Service Types and Services}, for an example).
34607 Each extension must pass a list of @code{<shepherd-service>}. Its
34608 value must be a @code{shepherd-configuration}, as described below.
34611 @deftp {Data Type} shepherd-configuration
34612 This data type represents the Shepherd's configuration.
34615 @item shepherd (default: @code{shepherd})
34616 The Shepherd package to use.
34618 @item services (default: @code{'()})
34619 A list of @code{<shepherd-service>} to start.
34620 You should probably use the service extension
34621 mechanism instead (@pxref{Shepherd Services}).
34625 The following example specifies the Shepherd package for the operating
34631 (services (append (list openssh-service-type))
34635 ;; Use own Shepherd package.
34636 (essential-services
34637 (modify-services (operating-system-default-essential-services
34638 this-operating-system)
34639 (shepherd-root-service-type config => (shepherd-configuration
34641 (shepherd my-shepherd))))))
34644 @defvr {Scheme Variable} %shepherd-root-service
34645 This service represents PID@tie{}1.
34649 @node Documentation
34650 @chapter Documentation
34652 @cindex documentation, searching for
34653 @cindex searching for documentation
34654 @cindex Info, documentation format
34656 @cindex manual pages
34657 In most cases packages installed with Guix come with documentation.
34658 There are two main documentation formats: ``Info'', a browsable
34659 hypertext format used for GNU software, and ``manual pages'' (or ``man
34660 pages''), the linear documentation format traditionally found on Unix.
34661 Info manuals are accessed with the @command{info} command or with Emacs,
34662 and man pages are accessed using @command{man}.
34664 You can look for documentation of software installed on your system by
34665 keyword. For example, the following command searches for information
34666 about ``TLS'' in Info manuals:
34670 "(emacs)Network Security" -- STARTTLS
34671 "(emacs)Network Security" -- TLS
34672 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
34673 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
34678 The command below searches for the same keyword in man pages:
34682 SSL (7) - OpenSSL SSL/TLS library
34683 certtool (1) - GnuTLS certificate tool
34687 These searches are purely local to your computer so you have the
34688 guarantee that documentation you find corresponds to what you have
34689 actually installed, you can access it off-line, and your privacy is
34692 Once you have these results, you can view the relevant documentation by
34696 $ info "(gnutls)Core TLS API"
34706 Info manuals contain sections and indices as well as hyperlinks like
34707 those found in Web pages. The @command{info} reader (@pxref{Top, Info
34708 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
34709 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
34710 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
34711 Introduction}, for an introduction to Info navigation.
34713 @node Installing Debugging Files
34714 @chapter Installing Debugging Files
34716 @cindex debugging files
34717 Program binaries, as produced by the GCC compilers for instance, are
34718 typically written in the ELF format, with a section containing
34719 @dfn{debugging information}. Debugging information is what allows the
34720 debugger, GDB, to map binary code to source code; it is required to
34721 debug a compiled program in good conditions.
34723 This chapter explains how to use separate debug info when packages
34724 provide it, and how to rebuild packages with debug info when it's
34728 * Separate Debug Info:: Installing 'debug' outputs.
34729 * Rebuilding Debug Info:: Building missing debug info.
34732 @node Separate Debug Info
34733 @section Separate Debug Info
34735 The problem with debugging information is that is takes up a fair amount
34736 of disk space. For example, debugging information for the GNU C Library
34737 weighs in at more than 60 MiB@. Thus, as a user, keeping all the
34738 debugging info of all the installed programs is usually not an option.
34739 Yet, space savings should not come at the cost of an impediment to
34740 debugging---especially in the GNU system, which should make it easier
34741 for users to exert their computing freedom (@pxref{GNU Distribution}).
34743 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
34744 mechanism that allows users to get the best of both worlds: debugging
34745 information can be stripped from the binaries and stored in separate
34746 files. GDB is then able to load debugging information from those files,
34747 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
34750 The GNU distribution takes advantage of this by storing debugging
34751 information in the @code{lib/debug} sub-directory of a separate package
34752 output unimaginatively called @code{debug} (@pxref{Packages with
34753 Multiple Outputs}). Users can choose to install the @code{debug} output
34754 of a package when they need it. For instance, the following command
34755 installs the debugging information for the GNU C Library and for GNU
34759 guix install glibc:debug guile:debug
34762 GDB must then be told to look for debug files in the user's profile, by
34763 setting the @code{debug-file-directory} variable (consider setting it
34764 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
34768 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
34771 From there on, GDB will pick up debugging information from the
34772 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
34774 In addition, you will most likely want GDB to be able to show the source
34775 code being debugged. To do that, you will have to unpack the source
34776 code of the package of interest (obtained with @code{guix build
34777 --source}, @pxref{Invoking guix build}), and to point GDB to that source
34778 directory using the @code{directory} command (@pxref{Source Path,
34779 @code{directory},, gdb, Debugging with GDB}).
34781 @c XXX: keep me up-to-date
34782 The @code{debug} output mechanism in Guix is implemented by the
34783 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
34784 opt-in---debugging information is available only for the packages with
34785 definitions explicitly declaring a @code{debug} output. To check
34786 whether a package has a @code{debug} output, use @command{guix package
34787 --list-available} (@pxref{Invoking guix package}).
34789 Read on for how to deal with packages lacking a @code{debug} output.
34791 @node Rebuilding Debug Info
34792 @section Rebuilding Debug Info
34794 @cindex debugging info, rebuilding
34795 As we saw above, some packages, but not all, provide debugging info in a
34796 @code{debug} output. What can you do when debugging info is missing?
34797 The @option{--with-debug-info} option provides a solution to that: it
34798 allows you to rebuild the package(s) for which debugging info is
34799 missing---and only those---and to graft those onto the application
34800 you're debugging. Thus, while it's not as fast as installing a
34801 @code{debug} output, it is relatively inexpensive.
34803 Let's illustrate that. Suppose you're experiencing a bug in Inkscape
34804 and would like to see what's going on in GLib, a library that's deep
34805 down in its dependency graph. As it turns out, GLib does not have a
34806 @code{debug} output and the backtrace GDB shows is all sadness:
34810 #0 0x00007ffff5f92190 in g_getenv ()
34811 from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
34812 #1 0x00007ffff608a7d6 in gobject_init_ctor ()
34813 from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
34814 #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
34815 env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
34816 #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
34820 To address that, you install Inkscape linked against a variant GLib that
34821 contains debug info:
34824 guix install inkscape --with-debug-info=glib
34827 This time, debugging will be a whole lot nicer:
34830 $ gdb --args sh -c 'exec inkscape'
34833 Function "g_getenv" not defined.
34834 Make breakpoint pending on future shared library load? (y or [n]) y
34835 Breakpoint 1 (g_getenv) pending.
34837 Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
34840 #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
34841 #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
34842 #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
34843 #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
34844 env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
34850 Note that there can be packages for which @option{--with-debug-info}
34851 will not have the desired effect. @xref{Package Transformation Options,
34852 @option{--with-debug-info}}, for more information.
34854 @node Security Updates
34855 @chapter Security Updates
34857 @cindex security updates
34858 @cindex security vulnerabilities
34859 Occasionally, important security vulnerabilities are discovered in software
34860 packages and must be patched. Guix developers try hard to keep track of
34861 known vulnerabilities and to apply fixes as soon as possible in the
34862 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
34863 containing only security updates). The @command{guix lint} tool helps
34864 developers find out about vulnerable versions of software packages in the
34869 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
34870 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
34871 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
34875 @xref{Invoking guix lint}, for more information.
34877 Guix follows a functional
34878 package management discipline (@pxref{Introduction}), which implies
34879 that, when a package is changed, @emph{every package that depends on it}
34880 must be rebuilt. This can significantly slow down the deployment of
34881 fixes in core packages such as libc or Bash, since basically the whole
34882 distribution would need to be rebuilt. Using pre-built binaries helps
34883 (@pxref{Substitutes}), but deployment may still take more time than
34887 To address this, Guix implements @dfn{grafts}, a mechanism that allows
34888 for fast deployment of critical updates without the costs associated
34889 with a whole-distribution rebuild. The idea is to rebuild only the
34890 package that needs to be patched, and then to ``graft'' it onto packages
34891 explicitly installed by the user and that were previously referring to
34892 the original package. The cost of grafting is typically very low, and
34893 order of magnitudes lower than a full rebuild of the dependency chain.
34895 @cindex replacements of packages, for grafts
34896 For instance, suppose a security update needs to be applied to Bash.
34897 Guix developers will provide a package definition for the ``fixed''
34898 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
34899 Packages}). Then, the original package definition is augmented with a
34900 @code{replacement} field pointing to the package containing the bug fix:
34907 (replacement bash-fixed)))
34910 From there on, any package depending directly or indirectly on Bash---as
34911 reported by @command{guix gc --requisites} (@pxref{Invoking guix
34912 gc})---that is installed is automatically ``rewritten'' to refer to
34913 @code{bash-fixed} instead of @code{bash}. This grafting process takes
34914 time proportional to the size of the package, usually less than a
34915 minute for an ``average'' package on a recent machine. Grafting is
34916 recursive: when an indirect dependency requires grafting, then grafting
34917 ``propagates'' up to the package that the user is installing.
34919 Currently, the length of the name and version of the graft and that of
34920 the package it replaces (@code{bash-fixed} and @code{bash} in the example
34921 above) must be equal. This restriction mostly comes from the fact that
34922 grafting works by patching files, including binary files, directly.
34923 Other restrictions may apply: for instance, when adding a graft to a
34924 package providing a shared library, the original shared library and its
34925 replacement must have the same @code{SONAME} and be binary-compatible.
34927 The @option{--no-grafts} command-line option allows you to forcefully
34928 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
34932 guix build bash --no-grafts
34936 returns the store file name of the original Bash, whereas:
34943 returns the store file name of the ``fixed'', replacement Bash. This
34944 allows you to distinguish between the two variants of Bash.
34946 To verify which Bash your whole profile refers to, you can run
34947 (@pxref{Invoking guix gc}):
34950 guix gc -R $(readlink -f ~/.guix-profile) | grep bash
34954 @dots{} and compare the store file names that you get with those above.
34955 Likewise for a complete Guix system generation:
34958 guix gc -R $(guix system build my-config.scm) | grep bash
34961 Lastly, to check which Bash running processes are using, you can use the
34962 @command{lsof} command:
34965 lsof | grep /gnu/store/.*bash
34969 @node Bootstrapping
34970 @chapter Bootstrapping
34972 @c Adapted from the ELS 2013 paper.
34974 @cindex bootstrapping
34976 Bootstrapping in our context refers to how the distribution gets built
34977 ``from nothing''. Remember that the build environment of a derivation
34978 contains nothing but its declared inputs (@pxref{Introduction}). So
34979 there's an obvious chicken-and-egg problem: how does the first package
34980 get built? How does the first compiler get compiled?
34982 It is tempting to think of this question as one that only die-hard
34983 hackers may care about. However, while the answer to that question is
34984 technical in nature, its implications are wide-ranging. How the
34985 distribution is bootstrapped defines the extent to which we, as
34986 individuals and as a collective of users and hackers, can trust the
34987 software we run. It is a central concern from the standpoint of
34988 @emph{security} and from a @emph{user freedom} viewpoint.
34990 @cindex bootstrap binaries
34991 The GNU system is primarily made of C code, with libc at its core. The
34992 GNU build system itself assumes the availability of a Bourne shell and
34993 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
34994 `grep'. Furthermore, build programs---programs that run
34995 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
34996 (@pxref{Derivations}). Consequently, to be able to build anything at
34997 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
34998 Binutils, libc, and the other packages mentioned above---the
34999 @dfn{bootstrap binaries}.
35001 These bootstrap binaries are ``taken for granted'', though we can also
35002 re-create them if needed (@pxref{Preparing to Use the Bootstrap
35006 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
35007 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
35010 @node Reduced Binary Seed Bootstrap
35011 @section The Reduced Binary Seed Bootstrap
35013 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
35014 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
35015 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
35016 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
35017 ``taken for granted.''
35019 Taking the bootstrap binaries for granted means that we consider them to
35020 be a correct and trustworthy ``seed'' for building the complete system.
35021 Therein lies a problem: the combined size of these bootstrap binaries is
35022 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
35023 or even inspecting these is next to impossible.
35025 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
35026 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
35027 Source Bootstrap'' and while we are working towards that goal it would
35028 be hyperbole to use that term for what we do now.}.
35030 The Reduced Binary Seed bootstrap removes the most critical tools---from a
35031 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
35032 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
35033 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
35034 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
35036 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
35037 C Library are built from source. From here on the more traditional
35038 bootstrap process resumes. This approach has reduced the bootstrap
35039 binaries in size to about 145MB in Guix v1.1.
35041 The next step that Guix has taken is to replace the shell and all its
35042 utilities with implementations in Guile Scheme, the @emph{Scheme-only
35043 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
35044 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
35045 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
35046 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
35047 removed are now built from source.
35049 Building the GNU System from source is currently only possible by adding
35050 some historical GNU packages as intermediate steps@footnote{Packages
35051 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
35052 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
35053 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
35054 and GNU packages become more bootstrappable again (e.g., new releases of
35055 GNU Sed will also ship as gzipped tarballs again, as alternative to the
35056 hard to bootstrap @code{xz}-compression), this set of added packages can
35057 hopefully be reduced again.
35059 The graph below shows the resulting dependency graph for
35060 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
35061 traditional bootstrap of the rest of the Guix System.
35063 @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
35064 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
35066 The only significant binary bootstrap seeds that remain@footnote{
35067 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
35068 together with @code{mes}.} are a Scheme interpreter and a Scheme
35069 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
35070 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
35071 to get Guile running.}.
35073 This further reduction has brought down the size of the binary seed to
35074 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
35076 Work is ongoing to remove all binary blobs from our free software
35077 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
35078 is work to bring these bootstraps to the @code{arm-linux} and
35079 @code{aarch64-linux} architectures and to the Hurd.
35081 If you are interested, join us on @samp{#bootstrappable} on the Freenode
35082 IRC network or discuss on @email{bug-mes@@gnu.org} or
35083 @email{gash-devel@@nongnu.org}.
35085 @node Preparing to Use the Bootstrap Binaries
35086 @section Preparing to Use the Bootstrap Binaries
35088 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
35089 @c large image, it's hard to scroll. Oh well.
35090 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
35092 The figure above shows the very beginning of the dependency graph of the
35093 distribution, corresponding to the package definitions of the @code{(gnu
35094 packages bootstrap)} module. A similar figure can be generated with
35095 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
35098 guix graph -t derivation \
35099 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
35100 | dot -Tps > gcc.ps
35103 or, for the further Reduced Binary Seed bootstrap
35106 guix graph -t derivation \
35107 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
35108 | dot -Tps > mes.ps
35111 At this level of detail, things are
35112 slightly complex. First, Guile itself consists of an ELF executable,
35113 along with many source and compiled Scheme files that are dynamically
35114 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
35115 tarball shown in this graph. This tarball is part of Guix's ``source''
35116 distribution, and gets inserted into the store with @code{add-to-store}
35117 (@pxref{The Store}).
35119 But how do we write a derivation that unpacks this tarball and adds it
35120 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
35121 derivation---the first one that gets built---uses @code{bash} as its
35122 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
35123 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
35124 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
35125 the Guix source distribution, whose sole purpose is to allow the Guile
35126 tarball to be unpacked.
35128 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
35129 Guile that can be used to run subsequent build programs. Its first task
35130 is to download tarballs containing the other pre-built binaries---this
35131 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
35132 @code{ftp-client.scm} are used for this purpose. The
35133 @code{module-import.drv} derivations import those modules in a directory
35134 in the store, using the original layout. The
35135 @code{module-import-compiled.drv} derivations compile those modules, and
35136 write them in an output directory with the right layout. This
35137 corresponds to the @code{#:modules} argument of
35138 @code{build-expression->derivation} (@pxref{Derivations}).
35140 Finally, the various tarballs are unpacked by the derivations
35141 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
35142 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
35143 point we have a working C tool chain.
35145 @unnumberedsec Building the Build Tools
35147 Bootstrapping is complete when we have a full tool chain that does not
35148 depend on the pre-built bootstrap tools discussed above. This
35149 no-dependency requirement is verified by checking whether the files of
35150 the final tool chain contain references to the @file{/gnu/store}
35151 directories of the bootstrap inputs. The process that leads to this
35152 ``final'' tool chain is described by the package definitions found in
35153 the @code{(gnu packages commencement)} module.
35155 The @command{guix graph} command allows us to ``zoom out'' compared to
35156 the graph above, by looking at the level of package objects instead of
35157 individual derivations---remember that a package may translate to
35158 several derivations, typically one derivation to download its source,
35159 one to build the Guile modules it needs, and one to actually build the
35160 package from source. The command:
35163 guix graph -t bag \
35164 -e '(@@@@ (gnu packages commencement)
35165 glibc-final-with-bootstrap-bash)' | xdot -
35169 displays the dependency graph leading to the ``final'' C
35170 library@footnote{You may notice the @code{glibc-intermediate} label,
35171 suggesting that it is not @emph{quite} final, but as a good
35172 approximation, we will consider it final.}, depicted below.
35174 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
35176 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
35177 The first tool that gets built with the bootstrap binaries is
35178 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
35179 for all the following packages. From there Findutils and Diffutils get
35182 Then come the first-stage Binutils and GCC, built as pseudo cross
35183 tools---i.e., with @option{--target} equal to @option{--host}. They are
35184 used to build libc. Thanks to this cross-build trick, this libc is
35185 guaranteed not to hold any reference to the initial tool chain.
35187 From there the final Binutils and GCC (not shown above) are built. GCC
35188 uses @command{ld} from the final Binutils, and links programs against
35189 the just-built libc. This tool chain is used to build the other
35190 packages used by Guix and by the GNU Build System: Guile, Bash,
35193 And voilà! At this point we have the complete set of build tools that
35194 the GNU Build System expects. These are in the @code{%final-inputs}
35195 variable of the @code{(gnu packages commencement)} module, and are
35196 implicitly used by any package that uses @code{gnu-build-system}
35197 (@pxref{Build Systems, @code{gnu-build-system}}).
35200 @unnumberedsec Building the Bootstrap Binaries
35202 @cindex bootstrap binaries
35203 Because the final tool chain does not depend on the bootstrap binaries,
35204 those rarely need to be updated. Nevertheless, it is useful to have an
35205 automated way to produce them, should an update occur, and this is what
35206 the @code{(gnu packages make-bootstrap)} module provides.
35208 The following command builds the tarballs containing the bootstrap binaries
35209 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
35210 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
35211 and Guile, and a tarball containing a mixture of Coreutils and other basic
35212 command-line tools):
35215 guix build bootstrap-tarballs
35218 The generated tarballs are those that should be referred to in the
35219 @code{(gnu packages bootstrap)} module mentioned at the beginning of
35222 Still here? Then perhaps by now you've started to wonder: when do we
35223 reach a fixed point? That is an interesting question! The answer is
35224 unknown, but if you would like to investigate further (and have
35225 significant computational and storage resources to do so), then let us
35228 @unnumberedsec Reducing the Set of Bootstrap Binaries
35230 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
35231 binary code! Why is that a problem? It's a problem because these big chunks
35232 of binary code are practically non-auditable, which makes it hard to establish
35233 what source code produced them. Every unauditable binary also leaves us
35234 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
35235 paper @emph{Reflections on Trusting Trust}.
35237 This is mitigated by the fact that our bootstrap binaries were generated
35238 from an earlier Guix revision. Nevertheless it lacks the level of
35239 transparency that we get in the rest of the package dependency graph,
35240 where Guix always gives us a source-to-binary mapping. Thus, our goal
35241 is to reduce the set of bootstrap binaries to the bare minimum.
35243 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
35244 on-going projects to do that. One of these is about replacing the
35245 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
35246 of increasing complexity, which could be built from source starting from
35247 a simple and auditable assembler.
35249 Our first major achievement is the replacement of of GCC, the GNU C Library
35250 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
35251 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
35252 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
35253 bootstrapped yet and thus we inject them as binary seeds. We call this the
35254 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
35255 binaries! Also, it has eliminated the C compiler binary; i686-linux and
35256 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
35258 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
35259 also looking at any other bootstrap binaries. Your help is welcome!
35262 @chapter Porting to a New Platform
35264 As discussed above, the GNU distribution is self-contained, and
35265 self-containment is achieved by relying on pre-built ``bootstrap
35266 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
35267 operating system kernel, CPU architecture, and application binary
35268 interface (ABI). Thus, to port the distribution to a platform that is
35269 not yet supported, one must build those bootstrap binaries, and update
35270 the @code{(gnu packages bootstrap)} module to use them on that platform.
35272 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
35273 When everything goes well, and assuming the GNU tool chain supports the
35274 target platform, this can be as simple as running a command like this
35278 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
35281 For this to work, the @code{glibc-dynamic-linker} procedure in
35282 @code{(gnu packages bootstrap)} must be augmented to return the right
35283 file name for libc's dynamic linker on that platform; likewise,
35284 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
35285 taught about the new platform.
35287 Once these are built, the @code{(gnu packages bootstrap)} module needs
35288 to be updated to refer to these binaries on the target platform. That
35289 is, the hashes and URLs of the bootstrap tarballs for the new platform
35290 must be added alongside those of the currently supported platforms. The
35291 bootstrap Guile tarball is treated specially: it is expected to be
35292 available locally, and @file{gnu/local.mk} has rules to download it for
35293 the supported architectures; a rule for the new platform must be added
35296 In practice, there may be some complications. First, it may be that the
35297 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
35298 above) is not recognized by all the GNU tools. Typically, glibc
35299 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
35300 configure flag (see @code{gcc.scm} for examples of how to handle this).
35301 Second, some of the required packages could fail to build for that
35302 platform. Lastly, the generated binaries could be broken for some
35305 @c *********************************************************************
35306 @include contributing.texi
35308 @c *********************************************************************
35309 @node Acknowledgments
35310 @chapter Acknowledgments
35312 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
35313 which was designed and
35314 implemented by Eelco Dolstra, with contributions from other people (see
35315 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
35316 management, and promoted unprecedented features, such as transactional
35317 package upgrades and rollbacks, per-user profiles, and referentially
35318 transparent build processes. Without this work, Guix would not exist.
35320 The Nix-based software distributions, Nixpkgs and NixOS, have also been
35321 an inspiration for Guix.
35323 GNU@tie{}Guix itself is a collective work with contributions from a
35324 number of people. See the @file{AUTHORS} file in Guix for more
35325 information on these fine people. The @file{THANKS} file lists people
35326 who have helped by reporting bugs, taking care of the infrastructure,
35327 providing artwork and themes, making suggestions, and more---thank you!
35330 @c *********************************************************************
35331 @node GNU Free Documentation License
35332 @appendix GNU Free Documentation License
35333 @cindex license, GNU Free Documentation License
35334 @include fdl-1.3.texi
35336 @c *********************************************************************
35337 @node Concept Index
35338 @unnumbered Concept Index
35341 @node Programming Index
35342 @unnumbered Programming Index
35343 @syncodeindex tp fn
35344 @syncodeindex vr fn
35349 @c Local Variables:
35350 @c ispell-local-dictionary: "american";