6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
12 @c Identifier of the OpenPGP key used to sign tarballs and such.
13 @set OPENPGP-SIGNING-KEY-ID 3CE464558A84FDC69DB40CFB090B11993D9AEBB5
14 @set OPENPGP-SIGNING-KEY-URL https://sv.gnu.org/people/viewgpg.php?user_id=15145
16 @c Base URL for downloads.
17 @set BASE-URL https://ftp.gnu.org/gnu/guix
19 @c The official substitute server used by default.
20 @set SUBSTITUTE-SERVER ci.guix.gnu.org
21 @set SUBSTITUTE-URL https://@value{SUBSTITUTE-SERVER}
24 Copyright @copyright{} 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 Ludovic Courtès@*
25 Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
26 Copyright @copyright{} 2013 Nikita Karetnikov@*
27 Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
28 Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
29 Copyright @copyright{} 2014 Pierre-Antoine Rault@*
30 Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
31 Copyright @copyright{} 2015, 2016, 2017, 2019, 2020, 2021 Leo Famulari@*
32 Copyright @copyright{} 2015, 2016, 2017, 2018, 2019, 2020 Ricardo Wurmus@*
33 Copyright @copyright{} 2016 Ben Woodcroft@*
34 Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
35 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020, 2021 Efraim Flashner@*
36 Copyright @copyright{} 2016 John Darrington@*
37 Copyright @copyright{} 2016, 2017 Nikita Gillmann@*
38 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Jan Nieuwenhuizen@*
39 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Julien Lepiller@*
40 Copyright @copyright{} 2016 Alex ter Weele@*
41 Copyright @copyright{} 2016, 2017, 2018, 2019 Christopher Baines@*
42 Copyright @copyright{} 2017, 2018, 2019 Clément Lassieur@*
43 Copyright @copyright{} 2017, 2018, 2020, 2021 Mathieu Othacehe@*
44 Copyright @copyright{} 2017 Federico Beffa@*
45 Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
46 Copyright @copyright{} 2017 Thomas Danckaert@*
47 Copyright @copyright{} 2017 humanitiesNerd@*
48 Copyright @copyright{} 2017, 2021 Christopher Lemmer Webber@*
49 Copyright @copyright{} 2017, 2018, 2019, 2020 Marius Bakke@*
50 Copyright @copyright{} 2017, 2019, 2020 Hartmut Goebel@*
51 Copyright @copyright{} 2017, 2019, 2020, 2021 Maxim Cournoyer@*
52 Copyright @copyright{} 2017, 2018, 2019, 2020 Tobias Geerinckx-Rice@*
53 Copyright @copyright{} 2017 George Clemmer@*
54 Copyright @copyright{} 2017 Andy Wingo@*
55 Copyright @copyright{} 2017, 2018, 2019, 2020 Arun Isaac@*
56 Copyright @copyright{} 2017 nee@*
57 Copyright @copyright{} 2018 Rutger Helling@*
58 Copyright @copyright{} 2018, 2021 Oleg Pykhalov@*
59 Copyright @copyright{} 2018 Mike Gerwitz@*
60 Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
61 Copyright @copyright{} 2018, 2019 Gábor Boskovits@*
62 Copyright @copyright{} 2018, 2019, 2020 Florian Pelz@*
63 Copyright @copyright{} 2018 Laura Lazzati@*
64 Copyright @copyright{} 2018 Alex Vong@*
65 Copyright @copyright{} 2019 Josh Holland@*
66 Copyright @copyright{} 2019, 2020 Diego Nicola Barbato@*
67 Copyright @copyright{} 2019 Ivan Petkov@*
68 Copyright @copyright{} 2019 Jakob L. Kreuze@*
69 Copyright @copyright{} 2019 Kyle Andrews@*
70 Copyright @copyright{} 2019 Alex Griffin@*
71 Copyright @copyright{} 2019, 2020 Guillaume Le Vaillant@*
72 Copyright @copyright{} 2020 Leo Prikler@*
73 Copyright @copyright{} 2019, 2020 Simon Tournier@*
74 Copyright @copyright{} 2020 Wiktor Żelazny@*
75 Copyright @copyright{} 2020 Damien Cassou@*
76 Copyright @copyright{} 2020 Jakub Kądziołka@*
77 Copyright @copyright{} 2020 Jack Hill@*
78 Copyright @copyright{} 2020 Naga Malleswari@*
79 Copyright @copyright{} 2020 Brice Waegeneire@*
80 Copyright @copyright{} 2020 R Veera Kumar@*
81 Copyright @copyright{} 2020 Pierre Langlois@*
82 Copyright @copyright{} 2020 pinoaffe@*
83 Copyright @copyright{} 2020 André Batista@*
84 Copyright @copyright{} 2020, 2021 Alexandru-Sergiu Marton@*
85 Copyright @copyright{} 2020 raingloom@*
86 Copyright @copyright{} 2020 Daniel Brooks@*
87 Copyright @copyright{} 2020 John Soo@*
88 Copyright @copyright{} 2020 Jonathan Brielmaier@*
89 Copyright @copyright{} 2020 Edgar Vincent@*
91 Permission is granted to copy, distribute and/or modify this document
92 under the terms of the GNU Free Documentation License, Version 1.3 or
93 any later version published by the Free Software Foundation; with no
94 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
95 copy of the license is included in the section entitled ``GNU Free
96 Documentation License''.
99 @dircategory System administration
101 * Guix: (guix). Manage installed software and system configuration.
102 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
103 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
104 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
105 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
106 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
109 @dircategory Software development
111 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
112 * guix build: (guix)Invoking guix build. Building packages.
113 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
117 @title GNU Guix Reference Manual
118 @subtitle Using the GNU Guix Functional Package Manager
119 @author The GNU Guix Developers
122 @vskip 0pt plus 1filll
123 Edition @value{EDITION} @*
131 @c *********************************************************************
135 This document describes GNU Guix version @value{VERSION}, a functional
136 package management tool written for the GNU system.
138 @c TRANSLATORS: You can replace the following paragraph with information on
139 @c how to join your own translation team and how to report issues with the
141 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
142 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
143 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
144 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
145 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
146 would like to translate it in your native language, consider joining
147 @uref{https://translate.fedoraproject.org/projects/guix/documentation-manual,
151 * Introduction:: What is Guix about?
152 * Installation:: Installing Guix.
153 * System Installation:: Installing the whole operating system.
154 * Getting Started:: Your first steps.
155 * Package Management:: Package installation, upgrade, etc.
156 * Channels:: Customizing the package collection.
157 * Development:: Guix-aided software development.
158 * Programming Interface:: Using Guix in Scheme.
159 * Utilities:: Package management commands.
160 * System Configuration:: Configuring the operating system.
161 * Documentation:: Browsing software user manuals.
162 * Installing Debugging Files:: Feeding the debugger.
163 * Security Updates:: Deploying security fixes quickly.
164 * Bootstrapping:: GNU/Linux built from scratch.
165 * Porting:: Targeting another platform or kernel.
166 * Contributing:: Your help needed!
168 * Acknowledgments:: Thanks!
169 * GNU Free Documentation License:: The license of this manual.
170 * Concept Index:: Concepts.
171 * Programming Index:: Data types, functions, and variables.
174 --- The Detailed Node Listing ---
178 * Managing Software the Guix Way:: What's special.
179 * GNU Distribution:: The packages and tools.
183 * Binary Installation:: Getting Guix running in no time!
184 * Requirements:: Software needed to build and run Guix.
185 * Running the Test Suite:: Testing Guix.
186 * Setting Up the Daemon:: Preparing the build daemon's environment.
187 * Invoking guix-daemon:: Running the build daemon.
188 * Application Setup:: Application-specific setup.
189 * Upgrading Guix:: Upgrading Guix and its build daemon.
191 Setting Up the Daemon
193 * Build Environment Setup:: Preparing the isolated build environment.
194 * Daemon Offload Setup:: Offloading builds to remote machines.
195 * SELinux Support:: Using an SELinux policy for the daemon.
199 * Limitations:: What you can expect.
200 * Hardware Considerations:: Supported hardware.
201 * USB Stick and DVD Installation:: Preparing the installation medium.
202 * Preparing for Installation:: Networking, partitioning, etc.
203 * Guided Graphical Installation:: Easy graphical installation.
204 * Manual Installation:: Manual installation for wizards.
205 * After System Installation:: When installation succeeded.
206 * Installing Guix in a VM:: Guix System playground.
207 * Building the Installation Image:: How this comes to be.
211 * Keyboard Layout and Networking and Partitioning:: Initial setup.
212 * Proceeding with the Installation:: Installing.
216 * Features:: How Guix will make your life brighter.
217 * Invoking guix package:: Package installation, removal, etc.
218 * Substitutes:: Downloading pre-built binaries.
219 * Packages with Multiple Outputs:: Single source package, multiple outputs.
220 * Invoking guix gc:: Running the garbage collector.
221 * Invoking guix pull:: Fetching the latest Guix and distribution.
222 * Invoking guix time-machine:: Running an older revision of Guix.
223 * Inferiors:: Interacting with another revision of Guix.
224 * Invoking guix describe:: Display information about your Guix revision.
225 * Invoking guix archive:: Exporting and importing store files.
229 * Official Substitute Server:: One particular source of substitutes.
230 * Substitute Server Authorization:: How to enable or disable substitutes.
231 * Getting Substitutes from Other Servers:: Substitute diversity.
232 * Substitute Authentication:: How Guix verifies substitutes.
233 * Proxy Settings:: How to get substitutes via proxy.
234 * Substitution Failure:: What happens when substitution fails.
235 * On Trusting Binaries:: How can you trust that binary blob?
239 * Specifying Additional Channels:: Extending the package collection.
240 * Using a Custom Guix Channel:: Using a customized Guix.
241 * Replicating Guix:: Running the @emph{exact same} Guix.
242 * Channel Authentication:: How Guix verifies what it fetches.
243 * Creating a Channel:: How to write your custom channel.
244 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
245 * Declaring Channel Dependencies:: How to depend on other channels.
246 * Specifying Channel Authorizations:: Defining channel authors authorizations.
247 * Primary URL:: Distinguishing mirror to original.
248 * Writing Channel News:: Communicating information to channel's users.
249 * Channels with Substitutes:: Using channels with available substitutes.
253 * Invoking guix environment:: Setting up development environments.
254 * Invoking guix pack:: Creating software bundles.
255 * The GCC toolchain:: Working with languages supported by GCC.
256 * Invoking guix git authenticate:: Authenticating Git repositories.
258 Programming Interface
260 * Package Modules:: Packages from the programmer's viewpoint.
261 * Defining Packages:: Defining new packages.
262 * Defining Package Variants:: Customizing packages.
263 * Build Systems:: Specifying how packages are built.
264 * Build Phases:: Phases of the build process of a package.
265 * Build Utilities:: Helpers for your package definitions and more.
266 * The Store:: Manipulating the package store.
267 * Derivations:: Low-level interface to package derivations.
268 * The Store Monad:: Purely functional interface to the store.
269 * G-Expressions:: Manipulating build expressions.
270 * Invoking guix repl:: Programming Guix in Guile.
274 * package Reference:: The package data type.
275 * origin Reference:: The origin data type.
279 * Invoking guix build:: Building packages from the command line.
280 * Invoking guix edit:: Editing package definitions.
281 * Invoking guix download:: Downloading a file and printing its hash.
282 * Invoking guix hash:: Computing the cryptographic hash of a file.
283 * Invoking guix import:: Importing package definitions.
284 * Invoking guix refresh:: Updating package definitions.
285 * Invoking guix lint:: Finding errors in package definitions.
286 * Invoking guix size:: Profiling disk usage.
287 * Invoking guix graph:: Visualizing the graph of packages.
288 * Invoking guix publish:: Sharing substitutes.
289 * Invoking guix challenge:: Challenging substitute servers.
290 * Invoking guix copy:: Copying to and from a remote store.
291 * Invoking guix container:: Process isolation.
292 * Invoking guix weather:: Assessing substitute availability.
293 * Invoking guix processes:: Listing client processes.
295 Invoking @command{guix build}
297 * Common Build Options:: Build options for most commands.
298 * Package Transformation Options:: Creating variants of packages.
299 * Additional Build Options:: Options specific to 'guix build'.
300 * Debugging Build Failures:: Real life packaging experience.
304 * Using the Configuration System:: Customizing your GNU system.
305 * operating-system Reference:: Detail of operating-system declarations.
306 * File Systems:: Configuring file system mounts.
307 * Mapped Devices:: Block device extra processing.
308 * User Accounts:: Specifying user accounts.
309 * Keyboard Layout:: How the system interprets key strokes.
310 * Locales:: Language and cultural convention settings.
311 * Services:: Specifying system services.
312 * Setuid Programs:: Programs running with root privileges.
313 * X.509 Certificates:: Authenticating HTTPS servers.
314 * Name Service Switch:: Configuring libc's name service switch.
315 * Initial RAM Disk:: Linux-Libre bootstrapping.
316 * Bootloader Configuration:: Configuring the boot loader.
317 * Invoking guix system:: Instantiating a system configuration.
318 * Invoking guix deploy:: Deploying a system configuration to a remote host.
319 * Running Guix in a VM:: How to run Guix System in a virtual machine.
320 * Defining Services:: Adding new service definitions.
324 * Base Services:: Essential system services.
325 * Scheduled Job Execution:: The mcron service.
326 * Log Rotation:: The rottlog service.
327 * Networking Services:: Network setup, SSH daemon, etc.
328 * Unattended Upgrades:: Automated system upgrades.
329 * X Window:: Graphical display.
330 * Printing Services:: Local and remote printer support.
331 * Desktop Services:: D-Bus and desktop services.
332 * Sound Services:: ALSA and Pulseaudio services.
333 * Database Services:: SQL databases, key-value stores, etc.
334 * Mail Services:: IMAP, POP3, SMTP, and all that.
335 * Messaging Services:: Messaging services.
336 * Telephony Services:: Telephony services.
337 * Monitoring Services:: Monitoring services.
338 * Kerberos Services:: Kerberos services.
339 * LDAP Services:: LDAP services.
340 * Web Services:: Web servers.
341 * Certificate Services:: TLS certificates via Let's Encrypt.
342 * DNS Services:: DNS daemons.
343 * VPN Services:: VPN daemons.
344 * Network File System:: NFS related services.
345 * Continuous Integration:: The Cuirass service.
346 * Power Management Services:: Extending battery life.
347 * Audio Services:: The MPD.
348 * Virtualization Services:: Virtualization services.
349 * Version Control Services:: Providing remote access to Git repositories.
350 * Game Services:: Game servers.
351 * PAM Mount Service:: Service to mount volumes when logging in.
352 * Guix Services:: Services relating specifically to Guix.
353 * Linux Services:: Services tied to the Linux kernel.
354 * Hurd Services:: Services specific for a Hurd System.
355 * Miscellaneous Services:: Other services.
359 * Service Composition:: The model for composing services.
360 * Service Types and Services:: Types and services.
361 * Service Reference:: API reference.
362 * Shepherd Services:: A particular type of service.
364 Installing Debugging Files
366 * Separate Debug Info:: Installing 'debug' outputs.
367 * Rebuilding Debug Info:: Building missing debug info.
371 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
372 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
377 @c *********************************************************************
379 @chapter Introduction
382 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
383 using the international phonetic alphabet (IPA).} is a package
384 management tool for and distribution of the GNU system.
385 Guix makes it easy for unprivileged
386 users to install, upgrade, or remove software packages, to roll back to a
387 previous package set, to build packages from source, and generally
388 assists with the creation and maintenance of software environments.
391 @cindex GuixSD, now Guix System
392 @cindex Guix System Distribution, now Guix System
393 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
394 complements the available tools without interference (@pxref{Installation}),
395 or you can use it as a standalone operating system distribution,
396 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
397 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
398 group everything under the ``Guix'' banner since, after all, Guix System is
399 readily available through the @command{guix system} command, even if you're
400 using a different distro underneath!}. @xref{GNU Distribution}.
403 * Managing Software the Guix Way:: What's special.
404 * GNU Distribution:: The packages and tools.
407 @node Managing Software the Guix Way
408 @section Managing Software the Guix Way
410 @cindex user interfaces
411 Guix provides a command-line package management interface
412 (@pxref{Package Management}), tools to help with software development
413 (@pxref{Development}), command-line utilities for more advanced usage
414 (@pxref{Utilities}), as well as Scheme programming interfaces
415 (@pxref{Programming Interface}).
417 Its @dfn{build daemon} is responsible for building packages on behalf of
418 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
419 binaries from authorized sources (@pxref{Substitutes}).
421 @cindex extensibility of the distribution
422 @cindex customization, of packages
423 Guix includes package definitions for many GNU and non-GNU packages, all
424 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
425 user's computing freedom}. It is @emph{extensible}: users can write
426 their own package definitions (@pxref{Defining Packages}) and make them
427 available as independent package modules (@pxref{Package Modules}). It
428 is also @emph{customizable}: users can @emph{derive} specialized package
429 definitions from existing ones, including from the command line
430 (@pxref{Package Transformation Options}).
432 @cindex functional package management
434 Under the hood, Guix implements the @dfn{functional package management}
435 discipline pioneered by Nix (@pxref{Acknowledgments}).
436 In Guix, the package build and installation process is seen
437 as a @emph{function}, in the mathematical sense. That function takes inputs,
438 such as build scripts, a compiler, and libraries, and
439 returns an installed package. As a pure function, its result depends
440 solely on its inputs---for instance, it cannot refer to software or
441 scripts that were not explicitly passed as inputs. A build function
442 always produces the same result when passed a given set of inputs. It
443 cannot alter the environment of the running system in
444 any way; for instance, it cannot create, modify, or delete files outside
445 of its build and installation directories. This is achieved by running
446 build processes in isolated environments (or @dfn{containers}), where only their
447 explicit inputs are visible.
450 The result of package build functions is @dfn{cached} in the file
451 system, in a special directory called @dfn{the store} (@pxref{The
452 Store}). Each package is installed in a directory of its own in the
453 store---by default under @file{/gnu/store}. The directory name contains
454 a hash of all the inputs used to build that package; thus, changing an
455 input yields a different directory name.
457 This approach is the foundation for the salient features of Guix: support
458 for transactional package upgrade and rollback, per-user installation, and
459 garbage collection of packages (@pxref{Features}).
462 @node GNU Distribution
463 @section GNU Distribution
466 Guix comes with a distribution of the GNU system consisting entirely of
467 free software@footnote{The term ``free'' here refers to the
468 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
469 users of that software}.}. The
470 distribution can be installed on its own (@pxref{System Installation}),
471 but it is also possible to install Guix as a package manager on top of
472 an installed GNU/Linux system (@pxref{Installation}). When we need to
473 distinguish between the two, we refer to the standalone distribution as
476 The distribution provides core GNU packages such as GNU libc, GCC, and
477 Binutils, as well as many GNU and non-GNU applications. The complete
478 list of available packages can be browsed
479 @url{https://www.gnu.org/software/guix/packages,on-line} or by
480 running @command{guix package} (@pxref{Invoking guix package}):
483 guix package --list-available
486 Our goal is to provide a practical 100% free software distribution of
487 Linux-based and other variants of GNU, with a focus on the promotion and
488 tight integration of GNU components, and an emphasis on programs and
489 tools that help users exert that freedom.
491 Packages are currently available on the following platforms:
496 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel.
499 Intel 32-bit architecture (IA32), Linux-Libre kernel.
502 ARMv7-A architecture with hard float, Thumb-2 and NEON,
503 using the EABI hard-float application binary interface (ABI),
504 and Linux-Libre kernel.
507 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
510 @uref{https://hurd.gnu.org, GNU/Hurd} on the Intel 32-bit architecture
513 This configuration is experimental and under development. The easiest
514 way for you to give it a try is by setting up an instance of
515 @code{hurd-vm-service-type} on your GNU/Linux machine
516 (@pxref{transparent-emulation-qemu, @code{hurd-vm-service-type}}).
517 @xref{Contributing}, on how to help!
519 @item mips64el-linux (deprecated)
520 little-endian 64-bit MIPS processors, specifically the Loongson series,
521 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
522 supported; in particular, there is no ongoing work to ensure that this
523 architecture still works. Should someone decide they wish to revive this
524 architecture then the code is still available.
528 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
529 configuration and Guix takes care of instantiating the configuration in a
530 transactional, reproducible, and stateless fashion (@pxref{System
531 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
532 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
533 Manual}), the well-known GNU utilities and tool chain, as well as the
534 graphical environment or system services of your choice.
536 Guix System is available on all the above platforms except
537 @code{mips64el-linux}.
540 For information on porting to other architectures or kernels,
543 Building this distribution is a cooperative effort, and you are invited
544 to join! @xref{Contributing}, for information about how you can help.
547 @c *********************************************************************
549 @chapter Installation
551 @cindex installing Guix
554 We recommend the use of this
555 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
556 shell installer script} to install Guix on top of a running GNU/Linux system,
557 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
558 with the installation of the package manager, which can be done on top of a
559 running GNU/Linux system. If, instead, you want to install the complete GNU
560 operating system, @pxref{System Installation}.} The script automates the
561 download, installation, and initial configuration of Guix. It should be run
565 @cindex foreign distro
566 @cindex directories related to foreign distro
567 When installed on a foreign distro, GNU@tie{}Guix complements the available
568 tools without interference. Its data lives exclusively in two directories,
569 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
570 such as @file{/etc}, are left untouched.
572 Once installed, Guix can be updated by running @command{guix pull}
573 (@pxref{Invoking guix pull}).
575 If you prefer to perform the installation steps manually or want to tweak
576 them, you may find the following subsections useful. They describe the
577 software requirements of Guix, as well as how to install it manually and get
581 * Binary Installation:: Getting Guix running in no time!
582 * Requirements:: Software needed to build and run Guix.
583 * Running the Test Suite:: Testing Guix.
584 * Setting Up the Daemon:: Preparing the build daemon's environment.
585 * Invoking guix-daemon:: Running the build daemon.
586 * Application Setup:: Application-specific setup.
587 * Upgrading Guix:: Upgrading Guix and its build daemon.
590 @node Binary Installation
591 @section Binary Installation
593 @cindex installing Guix from binaries
594 @cindex installer script
595 This section describes how to install Guix on an arbitrary system from a
596 self-contained tarball providing binaries for Guix and for all its
597 dependencies. This is often quicker than installing from source, which
598 is described in the next sections. The only requirement is to have
601 @c Note duplicated from the ``Installation'' node.
603 We recommend the use of this
604 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
605 shell installer script}. The script automates the download, installation, and
606 initial configuration steps described below. It should be run as the root
607 user. As root, you can thus run this:
611 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
612 chmod +x guix-install.sh
616 When you're done, @pxref{Application Setup} for extra configuration you
617 might need, and @ref{Getting Started} for your first steps!
620 Installing goes along these lines:
624 @cindex downloading Guix binary
625 Download the binary tarball from
626 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
627 where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
628 @code{i686} (32-bits) machine already running the kernel Linux, and so on
629 (@pxref{GNU Distribution}).
631 @c The following is somewhat duplicated in ``System Installation''.
632 Make sure to download the associated @file{.sig} file and to verify the
633 authenticity of the tarball against it, along these lines:
636 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
637 $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
640 If that command fails because you do not have the required public key,
641 then run this command to import it:
644 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
645 -qO - | gpg --import -
649 and rerun the @code{gpg --verify} command.
651 Take note that a warning like ``This key is not certified with a trusted
652 signature!'' is normal.
654 @c end authentication part
657 Now, you need to become the @code{root} user. Depending on your distribution,
658 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
662 # tar --warning=no-timestamp -xf \
663 /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
664 # mv var/guix /var/ && mv gnu /
667 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
668 The latter contains a ready-to-use profile for @code{root} (see next
671 Do @emph{not} unpack the tarball on a working Guix system since that
672 would overwrite its own essential files.
674 The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
675 not emit warnings about ``implausibly old time stamps'' (such
676 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
678 They stem from the fact that all the
679 files in the archive have their modification time set to 1 (which
680 means January 1st, 1970). This is done on purpose to make sure the
681 archive content is independent of its creation time, thus making it
685 Make the profile available under @file{~root/.config/guix/current}, which is
686 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
689 # mkdir -p ~root/.config/guix
690 # ln -sf /var/guix/profiles/per-user/root/current-guix \
691 ~root/.config/guix/current
694 Source @file{etc/profile} to augment @env{PATH} and other relevant
695 environment variables:
698 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
699 source $GUIX_PROFILE/etc/profile
703 Create the group and user accounts for build users as explained below
704 (@pxref{Build Environment Setup}).
707 Run the daemon, and set it to automatically start on boot.
709 If your host distro uses the systemd init system, this can be achieved
712 @c Versions of systemd that supported symlinked service files are not
713 @c yet widely deployed, so we should suggest that users copy the service
716 @c See this thread for more information:
717 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
720 # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
721 ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
723 # systemctl enable --now gnu-store.mount guix-daemon
726 If your host distro uses the Upstart init system:
729 # initctl reload-configuration
730 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
735 Otherwise, you can still start the daemon manually with:
738 # ~root/.config/guix/current/bin/guix-daemon \
739 --build-users-group=guixbuild
743 Make the @command{guix} command available to other users on the machine,
747 # mkdir -p /usr/local/bin
749 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
752 It is also a good idea to make the Info version of this manual available
756 # mkdir -p /usr/local/share/info
757 # cd /usr/local/share/info
758 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
762 That way, assuming @file{/usr/local/share/info} is in the search path,
763 running @command{info guix} will open this manual (@pxref{Other Info
764 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
768 @cindex substitutes, authorization thereof
769 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
770 (@pxref{Substitutes}), authorize them:
773 # guix archive --authorize < \
774 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
778 Each user may need to perform a few additional steps to make their Guix
779 environment ready for use, @pxref{Application Setup}.
782 Voilà, the installation is complete!
784 You can confirm that Guix is working by installing a sample package into
791 The binary installation tarball can be (re)produced and verified simply
792 by running the following command in the Guix source tree:
795 make guix-binary.@var{system}.tar.xz
799 ...@: which, in turn, runs:
802 guix pack -s @var{system} --localstatedir \
803 --profile-name=current-guix guix
806 @xref{Invoking guix pack}, for more info on this handy tool.
809 @section Requirements
811 This section lists requirements when building Guix from source. The
812 build procedure for Guix is the same as for other GNU software, and is
813 not covered here. Please see the files @file{README} and @file{INSTALL}
814 in the Guix source tree for additional details.
816 @cindex official website
817 GNU Guix is available for download from its website at
818 @url{https://www.gnu.org/software/guix/}.
820 GNU Guix depends on the following packages:
823 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x or
825 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
828 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
829 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
830 Guile,, gnutls-guile, GnuTLS-Guile});
832 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
834 @item @uref{https://notabug.org/guile-zlib/guile-zlib, Guile-zlib},
835 version 0.1.0 or later;
836 @item @uref{https://notabug.org/guile-lzlib/guile-lzlib, Guile-lzlib};
837 @item @uref{https://www.nongnu.org/guile-avahi/, Guile-Avahi};
839 @c FIXME: Specify a version number once a release has been made.
840 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, version 0.3.0
842 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON}
844 @item @url{https://www.gnu.org/software/make/, GNU Make}.
847 The following dependencies are optional:
851 @c Note: We need at least 0.13.0 for #:nodelay.
852 Support for build offloading (@pxref{Daemon Offload Setup}) and
853 @command{guix copy} (@pxref{Invoking guix copy}) depends on
854 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
855 version 0.13.0 or later.
858 @uref{https://notabug.org/guile-zstd/guile-zstd, Guile-zstd}, for zstd
859 compression and decompression in @command{guix publish} and for
860 substitutes (@pxref{Invoking guix publish}).
863 @uref{https://ngyro.com/software/guile-semver.html, Guile-Semver} for
864 the @code{crate} importer (@pxref{Invoking guix import}).
867 @uref{https://www.nongnu.org/guile-lib/doc/ref/htmlprag/, Guile-Lib} for
868 the @code{go} importer (@pxref{Invoking guix import}) and for some of
869 the ``updaters'' (@pxref{Invoking guix refresh}).
872 When @url{http://www.bzip.org, libbz2} is available,
873 @command{guix-daemon} can use it to compress build logs.
876 Unless @option{--disable-daemon} was passed to @command{configure}, the
877 following packages are also needed:
880 @item @url{https://gnupg.org/, GNU libgcrypt};
881 @item @url{https://sqlite.org, SQLite 3};
882 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
886 @cindex state directory
887 When configuring Guix on a system that already has a Guix installation,
888 be sure to specify the same state directory as the existing installation
889 using the @option{--localstatedir} option of the @command{configure}
890 script (@pxref{Directory Variables, @code{localstatedir},, standards,
891 GNU Coding Standards}). Usually, this @var{localstatedir} option is
892 set to the value @file{/var}. The @command{configure} script protects
893 against unintended misconfiguration of @var{localstatedir} so you do not
894 inadvertently corrupt your store (@pxref{The Store}).
896 @node Running the Test Suite
897 @section Running the Test Suite
900 After a successful @command{configure} and @code{make} run, it is a good
901 idea to run the test suite. It can help catch issues with the setup or
902 environment, or bugs in Guix itself---and really, reporting test
903 failures is a good way to help improve the software. To run the test
910 Test cases can run in parallel: you can use the @code{-j} option of
911 GNU@tie{}make to speed things up. The first run may take a few minutes
912 on a recent machine; subsequent runs will be faster because the store
913 that is created for test purposes will already have various things in
916 It is also possible to run a subset of the tests by defining the
917 @code{TESTS} makefile variable as in this example:
920 make check TESTS="tests/store.scm tests/cpio.scm"
923 By default, tests results are displayed at a file level. In order to
924 see the details of every individual test cases, it is possible to define
925 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
928 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
931 The underlying SRFI 64 custom Automake test driver used for the 'check'
932 test suite (located at @file{build-aux/test-driver.scm}) also allows
933 selecting which test cases to run at a finer level, via its
934 @option{--select} and @option{--exclude} options. Here's an example, to
935 run all the test cases from the @file{tests/packages.scm} test file
936 whose names start with ``transaction-upgrade-entry'':
939 export SCM_LOG_DRIVER_FLAGS="--select=^transaction-upgrade-entry"
940 make check TESTS="tests/packages.scm"
943 Those wishing to inspect the results of failed tests directly from the
944 command line can add the @option{--errors-only=yes} option to the
945 @code{SCM_LOG_DRIVER_FLAGS} makefile variable and set the @code{VERBOSE}
946 Automake makefile variable, as in:
949 make check SCM_LOG_DRIVER_FLAGS="--brief=no --errors-only=yes" VERBOSE=1
952 The @option{--show-duration=yes} option can be used to print the
953 duration of the individual test cases, when used in combination with
957 make check SCM_LOG_DRIVER_FLAGS="--brief=no --show-duration=yes"
960 @xref{Parallel Test Harness,,,automake,GNU Automake} for more
961 information about the Automake Parallel Test Harness.
963 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
964 @file{test-suite.log} file. Please specify the Guix version being used
965 as well as version numbers of the dependencies (@pxref{Requirements}) in
968 Guix also comes with a whole-system test suite that tests complete
969 Guix System instances. It can only run on systems where
970 Guix is already installed, using:
977 or, again, by defining @code{TESTS} to select a subset of tests to run:
980 make check-system TESTS="basic mcron"
983 These system tests are defined in the @code{(gnu tests @dots{})}
984 modules. They work by running the operating systems under test with
985 lightweight instrumentation in a virtual machine (VM). They can be
986 computationally intensive or rather cheap, depending on whether
987 substitutes are available for their dependencies (@pxref{Substitutes}).
988 Some of them require a lot of storage space to hold VM images.
990 Again in case of test failures, please send @email{bug-guix@@gnu.org}
993 @node Setting Up the Daemon
994 @section Setting Up the Daemon
997 Operations such as building a package or running the garbage collector
998 are all performed by a specialized process, the @dfn{build daemon}, on
999 behalf of clients. Only the daemon may access the store and its
1000 associated database. Thus, any operation that manipulates the store
1001 goes through the daemon. For instance, command-line tools such as
1002 @command{guix package} and @command{guix build} communicate with the
1003 daemon (@i{via} remote procedure calls) to instruct it what to do.
1005 The following sections explain how to prepare the build daemon's
1006 environment. See also @ref{Substitutes}, for information on how to allow
1007 the daemon to download pre-built binaries.
1010 * Build Environment Setup:: Preparing the isolated build environment.
1011 * Daemon Offload Setup:: Offloading builds to remote machines.
1012 * SELinux Support:: Using an SELinux policy for the daemon.
1015 @node Build Environment Setup
1016 @subsection Build Environment Setup
1018 @cindex build environment
1019 In a standard multi-user setup, Guix and its daemon---the
1020 @command{guix-daemon} program---are installed by the system
1021 administrator; @file{/gnu/store} is owned by @code{root} and
1022 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
1023 Guix tools to build packages or otherwise access the store, and the
1024 daemon will do it on their behalf, ensuring that the store is kept in a
1025 consistent state, and allowing built packages to be shared among users.
1028 When @command{guix-daemon} runs as @code{root}, you may not want package
1029 build processes themselves to run as @code{root} too, for obvious
1030 security reasons. To avoid that, a special pool of @dfn{build users}
1031 should be created for use by build processes started by the daemon.
1032 These build users need not have a shell and a home directory: they will
1033 just be used when the daemon drops @code{root} privileges in build
1034 processes. Having several such users allows the daemon to launch
1035 distinct build processes under separate UIDs, which guarantees that they
1036 do not interfere with each other---an essential feature since builds are
1037 regarded as pure functions (@pxref{Introduction}).
1039 On a GNU/Linux system, a build user pool may be created like this (using
1040 Bash syntax and the @code{shadow} commands):
1042 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
1043 @c for why `-G' is needed.
1045 # groupadd --system guixbuild
1046 # for i in `seq -w 1 10`;
1048 useradd -g guixbuild -G guixbuild \
1049 -d /var/empty -s `which nologin` \
1050 -c "Guix build user $i" --system \
1056 The number of build users determines how many build jobs may run in
1057 parallel, as specified by the @option{--max-jobs} option
1058 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
1059 @command{guix system vm} and related commands, you may need to add the
1060 build users to the @code{kvm} group so they can access @file{/dev/kvm},
1061 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
1062 (@pxref{Invoking guix system}).
1064 The @code{guix-daemon} program may then be run as @code{root} with the
1065 following command@footnote{If your machine uses the systemd init system,
1066 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
1067 file in @file{/etc/systemd/system} will ensure that
1068 @command{guix-daemon} is automatically started. Similarly, if your
1069 machine uses the Upstart init system, drop the
1070 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
1071 file in @file{/etc/init}.}:
1074 # guix-daemon --build-users-group=guixbuild
1079 This way, the daemon starts build processes in a chroot, under one of
1080 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
1081 environment contains nothing but:
1083 @c Keep this list in sync with libstore/build.cc! -----------------------
1086 a minimal @code{/dev} directory, created mostly independently from the
1087 host @code{/dev}@footnote{``Mostly'', because while the set of files
1088 that appear in the chroot's @code{/dev} is fixed, most of these files
1089 can only be created if the host has them.};
1092 the @code{/proc} directory; it only shows the processes of the container
1093 since a separate PID name space is used;
1096 @file{/etc/passwd} with an entry for the current user and an entry for
1100 @file{/etc/group} with an entry for the user's group;
1103 @file{/etc/hosts} with an entry that maps @code{localhost} to
1107 a writable @file{/tmp} directory.
1110 You can influence the directory where the daemon stores build trees
1111 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1112 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1113 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1114 This way, the value of @env{TMPDIR} does not leak inside build
1115 environments, which avoids discrepancies in cases where build processes
1116 capture the name of their build tree.
1120 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1121 environment variables for HTTP and HTTPS downloads it performs, be it
1122 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1123 (@pxref{Substitutes}).
1125 If you are installing Guix as an unprivileged user, it is still possible
1126 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1127 However, build processes will not be isolated from one another, and not
1128 from the rest of the system. Thus, build processes may interfere with
1129 each other, and may access programs, libraries, and other files
1130 available on the system---making it much harder to view them as
1131 @emph{pure} functions.
1134 @node Daemon Offload Setup
1135 @subsection Using the Offload Facility
1139 When desired, the build daemon can @dfn{offload} derivation builds to
1140 other machines running Guix, using the @code{offload} @dfn{build
1141 hook}@footnote{This feature is available only when
1142 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1143 present.}. When that feature is enabled, a list of user-specified build
1144 machines is read from @file{/etc/guix/machines.scm}; every time a build
1145 is requested, for instance via @code{guix build}, the daemon attempts to
1146 offload it to one of the machines that satisfy the constraints of the
1147 derivation, in particular its system types---e.g., @code{x86_64-linux}.
1148 A single machine can have multiple system types, either because its
1149 architecture natively supports it, via emulation
1150 (@pxref{transparent-emulation-qemu, Transparent Emulation with QEMU}),
1151 or both. Missing prerequisites for the build are
1152 copied over SSH to the target machine, which then proceeds with the
1153 build; upon success the output(s) of the build are copied back to the
1154 initial machine. The offload facility comes with a basic scheduler that
1155 attempts to select the best machine. The best machine is chosen among
1156 the available machines based on criteria such as:
1160 The availability of a build slot. A build machine can have as many
1161 build slots (connections) as the value of the @code{parallel-builds}
1162 field of its @code{build-machine} object.
1165 Its relative speed, as defined via the @code{speed} field of its
1166 @code{build-machine} object.
1169 Its load. The normalized machine load must be lower than a threshold
1170 value, configurable via the @code{overload-threshold} field of its
1171 @code{build-machine} object.
1174 Disk space availability. More than a 100 MiB must be available.
1177 The @file{/etc/guix/machines.scm} file typically looks like this:
1180 (list (build-machine
1181 (name "eightysix.example.org")
1182 (systems (list "x86_64-linux" "i686-linux"))
1183 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1185 (speed 2.)) ;incredibly fast!
1188 (name "armeight.example.org")
1189 (systems (list "aarch64-linux"))
1190 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1193 (string-append (getenv "HOME")
1194 "/.ssh/identity-for-guix"))))
1198 In the example above we specify a list of two build machines, one for
1199 the @code{x86_64} and @code{i686} architectures and one for the
1200 @code{aarch64} architecture.
1202 In fact, this file is---not surprisingly!---a Scheme file that is
1203 evaluated when the @code{offload} hook is started. Its return value
1204 must be a list of @code{build-machine} objects. While this example
1205 shows a fixed list of build machines, one could imagine, say, using
1206 DNS-SD to return a list of potential build machines discovered in the
1207 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1208 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1211 @deftp {Data Type} build-machine
1212 This data type represents build machines to which the daemon may offload
1213 builds. The important fields are:
1218 The host name of the remote machine.
1221 The system types the remote machine supports---e.g., @code{(list
1222 "x86_64-linux" "i686-linux")}.
1225 The user account to use when connecting to the remote machine over SSH.
1226 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1227 allow non-interactive logins.
1230 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1231 This is used to authenticate the machine when we connect to it. It is a
1232 long string that looks like this:
1235 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1238 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1239 key can be found in a file such as
1240 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1242 If the machine is running the SSH daemon of GNU@tie{}lsh,
1243 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1244 similar file. It can be converted to the OpenSSH format using
1245 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1248 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1249 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1254 A number of optional fields may be specified:
1258 @item @code{port} (default: @code{22})
1259 Port number of SSH server on the machine.
1261 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1262 The SSH private key file to use when connecting to the machine, in
1263 OpenSSH format. This key must not be protected with a passphrase.
1265 Note that the default value is the private key @emph{of the root
1266 account}. Make sure it exists if you use the default.
1268 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1269 @itemx @code{compression-level} (default: @code{3})
1270 The SSH-level compression methods and compression level requested.
1272 Note that offloading relies on SSH compression to reduce bandwidth usage
1273 when transferring files to and from build machines.
1275 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1276 File name of the Unix-domain socket @command{guix-daemon} is listening
1279 @item @code{overload-threshold} (default: @code{0.6})
1280 The load threshold above which a potential offload machine is
1281 disregarded by the offload scheduler. The value roughly translates to
1282 the total processor usage of the build machine, ranging from 0.0 (0%) to
1283 1.0 (100%). It can also be disabled by setting
1284 @code{overload-threshold} to @code{#f}.
1286 @item @code{parallel-builds} (default: @code{1})
1287 The number of builds that may run in parallel on the machine.
1289 @item @code{speed} (default: @code{1.0})
1290 A ``relative speed factor''. The offload scheduler will tend to prefer
1291 machines with a higher speed factor.
1293 @item @code{features} (default: @code{'()})
1294 A list of strings denoting specific features supported by the machine.
1295 An example is @code{"kvm"} for machines that have the KVM Linux modules
1296 and corresponding hardware support. Derivations can request features by
1297 name, and they will be scheduled on matching build machines.
1302 The @command{guix} command must be in the search path on the build
1303 machines. You can check whether this is the case by running:
1306 ssh build-machine guix repl --version
1309 There is one last thing to do once @file{machines.scm} is in place. As
1310 explained above, when offloading, files are transferred back and forth
1311 between the machine stores. For this to work, you first need to
1312 generate a key pair on each machine to allow the daemon to export signed
1313 archives of files from the store (@pxref{Invoking guix archive}):
1316 # guix archive --generate-key
1320 Each build machine must authorize the key of the master machine so that
1321 it accepts store items it receives from the master:
1324 # guix archive --authorize < master-public-key.txt
1328 Likewise, the master machine must authorize the key of each build machine.
1330 All the fuss with keys is here to express pairwise mutual trust
1331 relations between the master and the build machines. Concretely, when
1332 the master receives files from a build machine (and @i{vice versa}), its
1333 build daemon can make sure they are genuine, have not been tampered
1334 with, and that they are signed by an authorized key.
1336 @cindex offload test
1337 To test whether your setup is operational, run this command on the
1344 This will attempt to connect to each of the build machines specified in
1345 @file{/etc/guix/machines.scm}, make sure Guix is
1346 available on each machine, attempt to export to the machine and import
1347 from it, and report any error in the process.
1349 If you want to test a different machine file, just specify it on the
1353 # guix offload test machines-qualif.scm
1356 Last, you can test the subset of the machines whose name matches a
1357 regular expression like this:
1360 # guix offload test machines.scm '\.gnu\.org$'
1363 @cindex offload status
1364 To display the current load of all build hosts, run this command on the
1368 # guix offload status
1372 @node SELinux Support
1373 @subsection SELinux Support
1375 @cindex SELinux, daemon policy
1376 @cindex mandatory access control, SELinux
1377 @cindex security, guix-daemon
1378 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1379 can be installed on a system where SELinux is enabled, in order to label
1380 Guix files and to specify the expected behavior of the daemon. Since
1381 Guix System does not provide an SELinux base policy, the daemon policy cannot
1382 be used on Guix System.
1384 @subsubsection Installing the SELinux policy
1385 @cindex SELinux, policy installation
1386 To install the policy run this command as root:
1389 semodule -i etc/guix-daemon.cil
1392 Then relabel the file system with @code{restorecon} or by a different
1393 mechanism provided by your system.
1395 Once the policy is installed, the file system has been relabeled, and
1396 the daemon has been restarted, it should be running in the
1397 @code{guix_daemon_t} context. You can confirm this with the following
1401 ps -Zax | grep guix-daemon
1404 Monitor the SELinux log files as you run a command like @code{guix build
1405 hello} to convince yourself that SELinux permits all necessary
1408 @subsubsection Limitations
1409 @cindex SELinux, limitations
1411 This policy is not perfect. Here is a list of limitations or quirks
1412 that should be considered when deploying the provided SELinux policy for
1417 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1418 operations involve contexts that have anything to do with
1419 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1420 but it would be preferrable to define socket rules for only this label.
1423 @code{guix gc} cannot access arbitrary links to profiles. By design,
1424 the file label of the destination of a symlink is independent of the
1425 file label of the link itself. Although all profiles under
1426 $localstatedir are labelled, the links to these profiles inherit the
1427 label of the directory they are in. For links in the user’s home
1428 directory this will be @code{user_home_t}. But for links from the root
1429 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1430 directory, etc, this won’t work. @code{guix gc} would be prevented from
1431 reading and following these links.
1434 The daemon’s feature to listen for TCP connections might no longer work.
1435 This might require extra rules, because SELinux treats network sockets
1436 differently from files.
1439 Currently all files with a name matching the regular expression
1440 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1441 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1442 that name in any profile would be permitted to run in the
1443 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1444 build a package that provides this executable and convince a user to
1445 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1446 At that point SELinux could not prevent it from accessing files that are
1447 allowed for processes in that domain.
1449 You will need to relabel the store directory after all upgrades to
1450 @file{guix-daemon}, such as after running @code{guix pull}. Assuming the
1451 store is in @file{/gnu}, you can do this with @code{restorecon -vR /gnu},
1452 or by other means provided by your operating system.
1454 We could generate a much more restrictive policy at installation time,
1455 so that only the @emph{exact} file name of the currently installed
1456 @code{guix-daemon} executable would be labelled with
1457 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1458 The downside is that root would have to install or upgrade the policy at
1459 installation time whenever the Guix package that provides the
1460 effectively running @code{guix-daemon} executable is upgraded.
1463 @node Invoking guix-daemon
1464 @section Invoking @command{guix-daemon}
1466 The @command{guix-daemon} program implements all the functionality to
1467 access the store. This includes launching build processes, running the
1468 garbage collector, querying the availability of a build result, etc. It
1469 is normally run as @code{root} like this:
1472 # guix-daemon --build-users-group=guixbuild
1476 For details on how to set it up, @pxref{Setting Up the Daemon}.
1479 @cindex container, build environment
1480 @cindex build environment
1481 @cindex reproducible builds
1482 By default, @command{guix-daemon} launches build processes under
1483 different UIDs, taken from the build group specified with
1484 @option{--build-users-group}. In addition, each build process is run in a
1485 chroot environment that only contains the subset of the store that the
1486 build process depends on, as specified by its derivation
1487 (@pxref{Programming Interface, derivation}), plus a set of specific
1488 system directories. By default, the latter contains @file{/dev} and
1489 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1490 @dfn{container}: in addition to having its own file system tree, it has
1491 a separate mount name space, its own PID name space, network name space,
1492 etc. This helps achieve reproducible builds (@pxref{Features}).
1494 When the daemon performs a build on behalf of the user, it creates a
1495 build directory under @file{/tmp} or under the directory specified by
1496 its @env{TMPDIR} environment variable. This directory is shared with
1497 the container for the duration of the build, though within the container,
1498 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1500 The build directory is automatically deleted upon completion, unless the
1501 build failed and the client specified @option{--keep-failed}
1502 (@pxref{Common Build Options, @option{--keep-failed}}).
1504 The daemon listens for connections and spawns one sub-process for each session
1505 started by a client (one of the @command{guix} sub-commands). The
1506 @command{guix processes} command allows you to get an overview of the activity
1507 on your system by viewing each of the active sessions and clients.
1508 @xref{Invoking guix processes}, for more information.
1510 The following command-line options are supported:
1513 @item --build-users-group=@var{group}
1514 Take users from @var{group} to run build processes (@pxref{Setting Up
1515 the Daemon, build users}).
1517 @item --no-substitutes
1519 Do not use substitutes for build products. That is, always build things
1520 locally instead of allowing downloads of pre-built binaries
1521 (@pxref{Substitutes}).
1523 When the daemon runs with @option{--no-substitutes}, clients can still
1524 explicitly enable substitution @i{via} the @code{set-build-options}
1525 remote procedure call (@pxref{The Store}).
1527 @anchor{daemon-substitute-urls}
1528 @item --substitute-urls=@var{urls}
1529 Consider @var{urls} the default whitespace-separated list of substitute
1530 source URLs. When this option is omitted,
1531 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1533 This means that substitutes may be downloaded from @var{urls}, as long
1534 as they are signed by a trusted signature (@pxref{Substitutes}).
1536 @xref{Getting Substitutes from Other Servers}, for more information on
1537 how to configure the daemon to get substitutes from other servers.
1541 Do not use offload builds to other machines (@pxref{Daemon Offload
1542 Setup}). That is, always build things locally instead of offloading
1543 builds to remote machines.
1545 @item --cache-failures
1546 Cache build failures. By default, only successful builds are cached.
1548 When this option is used, @command{guix gc --list-failures} can be used
1549 to query the set of store items marked as failed; @command{guix gc
1550 --clear-failures} removes store items from the set of cached failures.
1551 @xref{Invoking guix gc}.
1553 @item --cores=@var{n}
1555 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1558 The default value is @code{0}, but it may be overridden by clients, such
1559 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1562 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1563 in the build process, which can then use it to exploit internal
1564 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1566 @item --max-jobs=@var{n}
1568 Allow at most @var{n} build jobs in parallel. The default value is
1569 @code{1}. Setting it to @code{0} means that no builds will be performed
1570 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1571 Setup}), or simply fail.
1573 @item --max-silent-time=@var{seconds}
1574 When the build or substitution process remains silent for more than
1575 @var{seconds}, terminate it and report a build failure.
1577 The default value is @code{0}, which disables the timeout.
1579 The value specified here can be overridden by clients (@pxref{Common
1580 Build Options, @option{--max-silent-time}}).
1582 @item --timeout=@var{seconds}
1583 Likewise, when the build or substitution process lasts for more than
1584 @var{seconds}, terminate it and report a build failure.
1586 The default value is @code{0}, which disables the timeout.
1588 The value specified here can be overridden by clients (@pxref{Common
1589 Build Options, @option{--timeout}}).
1591 @item --rounds=@var{N}
1592 Build each derivation @var{n} times in a row, and raise an error if
1593 consecutive build results are not bit-for-bit identical. Note that this
1594 setting can be overridden by clients such as @command{guix build}
1595 (@pxref{Invoking guix build}).
1597 When used in conjunction with @option{--keep-failed}, the differing
1598 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1599 This makes it easy to look for differences between the two results.
1602 Produce debugging output.
1604 This is useful to debug daemon start-up issues, but then it may be
1605 overridden by clients, for example the @option{--verbosity} option of
1606 @command{guix build} (@pxref{Invoking guix build}).
1608 @item --chroot-directory=@var{dir}
1609 Add @var{dir} to the build chroot.
1611 Doing this may change the result of build processes---for instance if
1612 they use optional dependencies found in @var{dir} when it is available,
1613 and not otherwise. For that reason, it is not recommended to do so.
1614 Instead, make sure that each derivation declares all the inputs that it
1617 @item --disable-chroot
1618 Disable chroot builds.
1620 Using this option is not recommended since, again, it would allow build
1621 processes to gain access to undeclared dependencies. It is necessary,
1622 though, when @command{guix-daemon} is running under an unprivileged user
1625 @item --log-compression=@var{type}
1626 Compress build logs according to @var{type}, one of @code{gzip},
1627 @code{bzip2}, or @code{none}.
1629 Unless @option{--lose-logs} is used, all the build logs are kept in the
1630 @var{localstatedir}. To save space, the daemon automatically compresses
1631 them with Bzip2 by default.
1633 @item --discover[=yes|no]
1634 Whether to discover substitute servers on the local network using mDNS
1637 This feature is still experimental. However, here are a few
1642 It might be faster/less expensive than fetching from remote servers;
1644 There are no security risks, only genuine substitutes will be used
1645 (@pxref{Substitute Authentication});
1647 An attacker advertising @command{guix publish} on your LAN cannot serve
1648 you malicious binaries, but they can learn what software you’re
1651 Servers may serve substitute over HTTP, unencrypted, so anyone on the
1652 LAN can see what software you’re installing.
1655 It is also possible to enable or disable substitute server discovery at
1656 run-time by running:
1659 herd discover guix-daemon on
1660 herd discover guix-daemon off
1663 @item --disable-deduplication
1664 @cindex deduplication
1665 Disable automatic file ``deduplication'' in the store.
1667 By default, files added to the store are automatically ``deduplicated'':
1668 if a newly added file is identical to another one found in the store,
1669 the daemon makes the new file a hard link to the other file. This can
1670 noticeably reduce disk usage, at the expense of slightly increased
1671 input/output load at the end of a build process. This option disables
1674 @item --gc-keep-outputs[=yes|no]
1675 Tell whether the garbage collector (GC) must keep outputs of live
1679 @cindex garbage collector roots
1680 When set to @code{yes}, the GC will keep the outputs of any live
1681 derivation available in the store---the @file{.drv} files. The default
1682 is @code{no}, meaning that derivation outputs are kept only if they are
1683 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1686 @item --gc-keep-derivations[=yes|no]
1687 Tell whether the garbage collector (GC) must keep derivations
1688 corresponding to live outputs.
1690 When set to @code{yes}, as is the case by default, the GC keeps
1691 derivations---i.e., @file{.drv} files---as long as at least one of their
1692 outputs is live. This allows users to keep track of the origins of
1693 items in their store. Setting it to @code{no} saves a bit of disk
1696 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1697 liveness to flow from outputs to derivations, and setting
1698 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1699 derivations to outputs. When both are set to @code{yes}, the effect is
1700 to keep all the build prerequisites (the sources, compiler, libraries,
1701 and other build-time tools) of live objects in the store, regardless of
1702 whether these prerequisites are reachable from a GC root. This is
1703 convenient for developers since it saves rebuilds or downloads.
1705 @item --impersonate-linux-2.6
1706 On Linux-based systems, impersonate Linux 2.6. This means that the
1707 kernel's @command{uname} system call will report 2.6 as the release number.
1709 This might be helpful to build programs that (usually wrongfully) depend
1710 on the kernel version number.
1713 Do not keep build logs. By default they are kept under
1714 @file{@var{localstatedir}/guix/log}.
1716 @item --system=@var{system}
1717 Assume @var{system} as the current system type. By default it is the
1718 architecture/kernel pair found at configure time, such as
1719 @code{x86_64-linux}.
1721 @item --listen=@var{endpoint}
1722 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1723 as the file name of a Unix-domain socket if it starts with
1724 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1725 host name or host name and port to listen to. Here are a few examples:
1728 @item --listen=/gnu/var/daemon
1729 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1730 creating it if needed.
1732 @item --listen=localhost
1733 @cindex daemon, remote access
1734 @cindex remote access to the daemon
1735 @cindex daemon, cluster setup
1736 @cindex clusters, daemon setup
1737 Listen for TCP connections on the network interface corresponding to
1738 @code{localhost}, on port 44146.
1740 @item --listen=128.0.0.42:1234
1741 Listen for TCP connections on the network interface corresponding to
1742 @code{128.0.0.42}, on port 1234.
1745 This option can be repeated multiple times, in which case
1746 @command{guix-daemon} accepts connections on all the specified
1747 endpoints. Users can tell client commands what endpoint to connect to
1748 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1749 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1752 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1753 @option{--listen=@var{host}} is suitable on local networks, such as
1754 clusters, where only trusted nodes may connect to the build daemon. In
1755 other cases where remote access to the daemon is needed, we recommend
1756 using Unix-domain sockets along with SSH.
1759 When @option{--listen} is omitted, @command{guix-daemon} listens for
1760 connections on the Unix-domain socket located at
1761 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1765 @node Application Setup
1766 @section Application Setup
1768 @cindex foreign distro
1769 When using Guix on top of GNU/Linux distribution other than Guix System---a
1770 so-called @dfn{foreign distro}---a few additional steps are needed to
1771 get everything in place. Here are some of them.
1775 @anchor{locales-and-locpath}
1776 @cindex locales, when not on Guix System
1778 @vindex GUIX_LOCPATH
1779 Packages installed @i{via} Guix will not use the locale data of the
1780 host system. Instead, you must first install one of the locale packages
1781 available with Guix and then define the @env{GUIX_LOCPATH} environment
1785 $ guix install glibc-locales
1786 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1789 Note that the @code{glibc-locales} package contains data for all the
1790 locales supported by the GNU@tie{}libc and weighs in at around
1791 917@tie{}MiB@. Alternatively, the @code{glibc-utf8-locales} is smaller but
1792 limited to a few UTF-8 locales.
1794 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1795 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1796 Manual}). There are two important differences though:
1800 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1801 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1802 to make sure the programs of the foreign distro will not end up loading
1803 incompatible locale data.
1806 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1807 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1808 should your Guix profile contain a mixture of programs linked against
1809 different libc version, each libc version will only try to load locale
1810 data in the right format.
1813 This is important because the locale data format used by different libc
1814 versions may be incompatible.
1816 @subsection Name Service Switch
1818 @cindex name service switch, glibc
1819 @cindex NSS (name service switch), glibc
1820 @cindex nscd (name service caching daemon)
1821 @cindex name service caching daemon (nscd)
1822 When using Guix on a foreign distro, we @emph{strongly recommend} that
1823 the system run the GNU C library's @dfn{name service cache daemon},
1824 @command{nscd}, which should be listening on the
1825 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1826 installed with Guix may fail to look up host names or user accounts, or
1827 may even crash. The next paragraphs explain why.
1829 @cindex @file{nsswitch.conf}
1830 The GNU C library implements a @dfn{name service switch} (NSS), which is
1831 an extensible mechanism for ``name lookups'' in general: host name
1832 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1833 The GNU C Library Reference Manual}).
1835 @cindex Network information service (NIS)
1836 @cindex NIS (Network information service)
1837 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1838 lookup implementations: for example, the @code{nss-mdns} plugin allow
1839 resolution of @code{.local} host names, the @code{nis} plugin allows
1840 user account lookup using the Network information service (NIS), and so
1841 on. These extra ``lookup services'' are configured system-wide in
1842 @file{/etc/nsswitch.conf}, and all the programs running on the system
1843 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1846 When they perform a name lookup---for instance by calling the
1847 @code{getaddrinfo} function in C---applications first try to connect to
1848 the nscd; on success, nscd performs name lookups on their behalf. If
1849 the nscd is not running, then they perform the name lookup by
1850 themselves, by loading the name lookup services into their own address
1851 space and running it. These name lookup services---the
1852 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1853 the host system's C library, rather than from the C library the
1854 application is linked against (the C library coming from Guix).
1856 And this is where the problem is: if your application is linked against
1857 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1858 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1859 likely crash or have its name lookups fail unexpectedly.
1861 Running @command{nscd} on the system, among other advantages, eliminates
1862 this binary incompatibility problem because those @code{libnss_*.so}
1863 files are loaded in the @command{nscd} process, not in applications
1866 @subsection X11 Fonts
1869 The majority of graphical applications use Fontconfig to locate and
1870 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1871 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1872 by default. Thus, to allow graphical applications installed with Guix
1873 to display fonts, you have to install fonts with Guix as well.
1874 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1875 @code{font-gnu-freefont}.
1877 @cindex @code{fc-cache}
1879 Once you have installed or removed fonts, or when you notice an
1880 application that does not find fonts, you may need to install Fontconfig
1881 and to force an update of its font cache by running:
1884 guix install fontconfig
1888 To display text written in Chinese languages, Japanese, or Korean in
1889 graphical applications, consider installing
1890 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1891 has multiple outputs, one per language family (@pxref{Packages with
1892 Multiple Outputs}). For instance, the following command installs fonts
1893 for Chinese languages:
1896 guix install font-adobe-source-han-sans:cn
1899 @cindex @code{xterm}
1900 Older programs such as @command{xterm} do not use Fontconfig and instead
1901 rely on server-side font rendering. Such programs require to specify a
1902 full name of a font using XLFD (X Logical Font Description), like this:
1905 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1908 To be able to use such full names for the TrueType fonts installed in
1909 your Guix profile, you need to extend the font path of the X server:
1911 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1912 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1914 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1917 @cindex @code{xlsfonts}
1918 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1919 to make sure your TrueType fonts are listed there.
1922 @subsection X.509 Certificates
1924 @cindex @code{nss-certs}
1925 The @code{nss-certs} package provides X.509 certificates, which allow
1926 programs to authenticate Web servers accessed over HTTPS.
1928 When using Guix on a foreign distro, you can install this package and
1929 define the relevant environment variables so that packages know where to
1930 look for certificates. @xref{X.509 Certificates}, for detailed
1933 @subsection Emacs Packages
1935 @cindex @code{emacs}
1936 When you install Emacs packages with Guix, the Elisp files are placed
1937 under the @file{share/emacs/site-lisp/} directory of the profile in
1938 which they are installed. The Elisp libraries are made available to
1939 Emacs through the @env{EMACSLOADPATH} environment variable, which is
1940 set when installing Emacs itself.
1942 Additionally, autoload definitions are automatically evaluated at the
1943 initialization of Emacs, by the Guix-specific
1944 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
1945 want to avoid auto-loading the Emacs packages installed with Guix, you
1946 can do so by running Emacs with the @option{--no-site-file} option
1947 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1950 @node Upgrading Guix
1951 @section Upgrading Guix
1953 @cindex Upgrading Guix, on a foreign distro
1955 To upgrade Guix, run:
1961 @xref{Invoking guix pull}, for more information.
1963 @cindex upgrading Guix for the root user, on a foreign distro
1964 @cindex upgrading the Guix daemon, on a foreign distro
1965 @cindex @command{guix pull} for the root user, on a foreign distro
1967 On a foreign distro, you can upgrade the build daemon by running:
1974 followed by (assuming your distro uses the systemd service management
1978 systemctl restart guix-daemon.service
1981 On Guix System, upgrading the daemon is achieved by reconfiguring the
1982 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
1986 @c *********************************************************************
1987 @node System Installation
1988 @chapter System Installation
1990 @cindex installing Guix System
1991 @cindex Guix System, installation
1992 This section explains how to install Guix System
1993 on a machine. Guix, as a package manager, can
1994 also be installed on top of a running GNU/Linux system,
1995 @pxref{Installation}.
1999 @c This paragraph is for people reading this from tty2 of the
2000 @c installation image.
2001 You are reading this documentation with an Info reader. For details on
2002 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
2003 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
2004 Info}. Hit @kbd{l} afterwards to come back here.
2006 Alternatively, run @command{info info} in another tty to keep the manual
2012 * Limitations:: What you can expect.
2013 * Hardware Considerations:: Supported hardware.
2014 * USB Stick and DVD Installation:: Preparing the installation medium.
2015 * Preparing for Installation:: Networking, partitioning, etc.
2016 * Guided Graphical Installation:: Easy graphical installation.
2017 * Manual Installation:: Manual installation for wizards.
2018 * After System Installation:: When installation succeeded.
2019 * Installing Guix in a VM:: Guix System playground.
2020 * Building the Installation Image:: How this comes to be.
2024 @section Limitations
2026 We consider Guix System to be ready for a wide range of ``desktop'' and server
2027 use cases. The reliability guarantees it provides---transactional upgrades
2028 and rollbacks, reproducibility---make it a solid foundation.
2030 Nevertheless, before you proceed with the installation, be aware of the
2031 following noteworthy limitations applicable to version @value{VERSION}:
2035 More and more system services are provided (@pxref{Services}), but some
2039 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
2040 as well as a number of X11 window managers. However, KDE is currently
2044 More than a disclaimer, this is an invitation to report issues (and success
2045 stories!), and to join us in improving it. @xref{Contributing}, for more
2049 @node Hardware Considerations
2050 @section Hardware Considerations
2052 @cindex hardware support on Guix System
2053 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
2054 builds around the kernel Linux-libre, which means that only hardware for
2055 which free software drivers and firmware exist is supported. Nowadays,
2056 a wide range of off-the-shelf hardware is supported on
2057 GNU/Linux-libre---from keyboards to graphics cards to scanners and
2058 Ethernet controllers. Unfortunately, there are still areas where
2059 hardware vendors deny users control over their own computing, and such
2060 hardware is not supported on Guix System.
2062 @cindex WiFi, hardware support
2063 One of the main areas where free drivers or firmware are lacking is WiFi
2064 devices. WiFi devices known to work include those using Atheros chips
2065 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
2066 driver, and those using Broadcom/AirForce chips (BCM43xx with
2067 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
2068 Linux-libre driver. Free firmware exists for both and is available
2069 out-of-the-box on Guix System, as part of @code{%base-firmware}
2070 (@pxref{operating-system Reference, @code{firmware}}).
2072 @cindex RYF, Respects Your Freedom
2073 The @uref{https://www.fsf.org/, Free Software Foundation} runs
2074 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
2075 certification program for hardware products that respect your freedom
2076 and your privacy and ensure that you have control over your device. We
2077 encourage you to check the list of RYF-certified devices.
2079 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
2080 web site. It contains a catalog of hardware devices with information
2081 about their support in GNU/Linux.
2084 @node USB Stick and DVD Installation
2085 @section USB Stick and DVD Installation
2087 An ISO-9660 installation image that can be written to a USB stick or
2088 burnt to a DVD can be downloaded from
2089 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz},
2090 where you can replace @code{x86_64-linux} with one of:
2094 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
2097 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
2100 @c start duplication of authentication part from ``Binary Installation''
2101 Make sure to download the associated @file{.sig} file and to verify the
2102 authenticity of the image against it, along these lines:
2105 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
2106 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
2109 If that command fails because you do not have the required public key,
2110 then run this command to import it:
2113 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
2114 -qO - | gpg --import -
2118 and rerun the @code{gpg --verify} command.
2120 Take note that a warning like ``This key is not certified with a trusted
2121 signature!'' is normal.
2125 This image contains the tools necessary for an installation.
2126 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
2128 @unnumberedsubsec Copying to a USB Stick
2130 To copy the image to a USB stick, follow these steps:
2134 Decompress the image using the @command{xz} command:
2137 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
2141 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
2142 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
2143 copy the image with:
2146 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX status=progress
2150 Access to @file{/dev/sdX} usually requires root privileges.
2153 @unnumberedsubsec Burning on a DVD
2155 To copy the image to a DVD, follow these steps:
2159 Decompress the image using the @command{xz} command:
2162 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
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.
2177 @unnumberedsubsec Booting
2179 Once this is done, you should be able to reboot the system and boot from
2180 the USB stick or DVD@. The latter usually requires you to get in the
2181 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2182 In order to boot from Libreboot, switch to the command mode by pressing
2183 the @kbd{c} key and type @command{search_grub usb}.
2185 @xref{Installing Guix in a VM}, if, instead, you would like to install
2186 Guix System in a virtual machine (VM).
2189 @node Preparing for Installation
2190 @section Preparing for Installation
2192 Once you have booted, you can use the guided graphical installer, which makes
2193 it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
2194 if you are already familiar with GNU/Linux and if you want more control than
2195 what the graphical installer provides, you can choose the ``manual''
2196 installation process (@pxref{Manual Installation}).
2198 The graphical installer is available on TTY1. You can obtain root shells on
2199 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2200 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2201 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2202 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2203 which allows you to select text with the left mouse button and to paste it
2204 with the middle button.
2207 Installation requires access to the Internet so that any missing
2208 dependencies of your system configuration can be downloaded. See the
2209 ``Networking'' section below.
2212 @node Guided Graphical Installation
2213 @section Guided Graphical Installation
2215 The graphical installer is a text-based user interface. It will guide you,
2216 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2218 The first dialog boxes allow you to set up the system as you use it during the
2219 installation: you can choose the language, keyboard layout, and set up
2220 networking, which will be used during the installation. The image below shows
2221 the networking dialog.
2223 @image{images/installer-network,5in,, networking setup with the graphical installer}
2225 Later steps allow you to partition your hard disk, as shown in the image
2226 below, to choose whether or not to use encrypted file systems, to enter the
2227 host name and root password, and to create an additional account, among other
2230 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2232 Note that, at any time, the installer allows you to exit the current
2233 installation step and resume at a previous step, as show in the image below.
2235 @image{images/installer-resume,5in,, resuming the installation process}
2237 Once you're done, the installer produces an operating system configuration and
2238 displays it (@pxref{Using the Configuration System}). At that point you can
2239 hit ``OK'' and installation will proceed. On success, you can reboot into the
2240 new system and enjoy. @xref{After System Installation}, for what's next!
2243 @node Manual Installation
2244 @section Manual Installation
2246 This section describes how you would ``manually'' install GNU@tie{}Guix System
2247 on your machine. This option requires familiarity with GNU/Linux, with the
2248 shell, and with common administration tools. If you think this is not for
2249 you, consider using the guided graphical installer (@pxref{Guided Graphical
2252 The installation system provides root shells on TTYs 3 to 6; press
2253 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2254 many common tools needed to install the system. But it is also a full-blown
2255 Guix System, which means that you can install additional packages, should you
2256 need it, using @command{guix package} (@pxref{Invoking guix package}).
2259 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2260 * Proceeding with the Installation:: Installing.
2263 @node Keyboard Layout and Networking and Partitioning
2264 @subsection Keyboard Layout, Networking, and Partitioning
2266 Before you can install the system, you may want to adjust the keyboard layout,
2267 set up networking, and partition your target hard disk. This section will
2268 guide you through this.
2270 @subsubsection Keyboard Layout
2272 @cindex keyboard layout
2273 The installation image uses the US qwerty keyboard layout. If you want
2274 to change it, you can use the @command{loadkeys} command. For example,
2275 the following command selects the Dvorak keyboard layout:
2281 See the files under @file{/run/current-system/profile/share/keymaps} for
2282 a list of available keyboard layouts. Run @command{man loadkeys} for
2285 @subsubsection Networking
2287 Run the following command to see what your network interfaces are called:
2294 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2300 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2301 Wired interfaces have a name starting with @samp{e}; for example, the
2302 interface corresponding to the first on-board Ethernet controller is
2303 called @samp{eno1}. Wireless interfaces have a name starting with
2304 @samp{w}, like @samp{w1p2s0}.
2307 @item Wired connection
2308 To configure a wired network run the following command, substituting
2309 @var{interface} with the name of the wired interface you want to use.
2312 ifconfig @var{interface} up
2316 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2319 ip link set @var{interface} up
2322 @item Wireless connection
2325 To configure wireless networking, you can create a configuration file
2326 for the @command{wpa_supplicant} configuration tool (its location is not
2327 important) using one of the available text editors such as
2331 nano wpa_supplicant.conf
2334 As an example, the following stanza can go to this file and will work
2335 for many wireless networks, provided you give the actual SSID and
2336 passphrase for the network you are connecting to:
2340 ssid="@var{my-ssid}"
2342 psk="the network's secret passphrase"
2346 Start the wireless service and run it in the background with the
2347 following command (substitute @var{interface} with the name of the
2348 network interface you want to use):
2351 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2354 Run @command{man wpa_supplicant} for more information.
2358 At this point, you need to acquire an IP address. On a network where IP
2359 addresses are automatically assigned @i{via} DHCP, you can run:
2362 dhclient -v @var{interface}
2365 Try to ping a server to see if networking is up and running:
2371 Setting up network access is almost always a requirement because the
2372 image does not contain all the software and tools that may be needed.
2374 @cindex proxy, during system installation
2375 If you need HTTP and HTTPS access to go through a proxy, run the
2379 herd set-http-proxy guix-daemon @var{URL}
2383 where @var{URL} is the proxy URL, for example
2384 @code{http://example.org:8118}.
2386 @cindex installing over SSH
2387 If you want to, you can continue the installation remotely by starting
2391 herd start ssh-daemon
2394 Make sure to either set a password with @command{passwd}, or configure
2395 OpenSSH public key authentication before logging in.
2397 @subsubsection Disk Partitioning
2399 Unless this has already been done, the next step is to partition, and
2400 then format the target partition(s).
2402 The installation image includes several partitioning tools, including
2403 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2404 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2405 the partition layout you want:
2411 If your disk uses the GUID Partition Table (GPT) format and you plan to
2412 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2413 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2416 @cindex EFI, installation
2417 @cindex UEFI, installation
2418 @cindex ESP, EFI system partition
2419 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2420 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2421 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2424 parted /dev/sda set 1 esp on
2428 @vindex grub-bootloader
2429 @vindex grub-efi-bootloader
2430 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2431 @file{/sys/firmware/efi} exists in the installation image, then you should
2432 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2433 Otherwise you should use the BIOS-based GRUB, known as
2434 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2438 Once you are done partitioning the target hard disk drive, you have to
2439 create a file system on the relevant partition(s)@footnote{Currently
2440 Guix System only supports ext4, btrfs, JFS, and F2FS file systems. In
2441 particular, code that reads file system UUIDs and labels only works for these
2442 file system types.}. For the ESP, if you have one and assuming it is
2443 @file{/dev/sda1}, run:
2446 mkfs.fat -F32 /dev/sda1
2449 For the root file system, ext4 is the most widely used format. Other
2450 file systems, such as Btrfs, support compression, which is reported to
2451 nicely complement file deduplication that the daemon performs
2452 independently of the file system (@pxref{Invoking guix-daemon,
2455 Preferably, assign file systems a label so that you can easily and
2456 reliably refer to them in @code{file-system} declarations (@pxref{File
2457 Systems}). This is typically done using the @code{-L} option of
2458 @command{mkfs.ext4} and related commands. So, assuming the target root
2459 partition lives at @file{/dev/sda2}, a file system with the label
2460 @code{my-root} can be created with:
2463 mkfs.ext4 -L my-root /dev/sda2
2466 @cindex encrypted disk
2467 If you are instead planning to encrypt the root partition, you can use
2468 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2469 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2470 @code{man cryptsetup}} for more information). Assuming you want to
2471 store the root partition on @file{/dev/sda2}, the command sequence would
2472 be along these lines:
2475 cryptsetup luksFormat /dev/sda2
2476 cryptsetup open --type luks /dev/sda2 my-partition
2477 mkfs.ext4 -L my-root /dev/mapper/my-partition
2480 Once that is done, mount the target file system under @file{/mnt}
2481 with a command like (again, assuming @code{my-root} is the label of the
2485 mount LABEL=my-root /mnt
2488 Also mount any other file systems you would like to use on the target
2489 system relative to this path. If you have opted for @file{/boot/efi} as an
2490 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2491 found by @code{guix system init} afterwards.
2493 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2494 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2495 sure to initialize them with @command{mkswap}. Assuming you have one
2496 swap partition on @file{/dev/sda3}, you would run:
2503 Alternatively, you may use a swap file. For example, assuming that in
2504 the new system you want to use the file @file{/swapfile} as a swap file,
2505 you would run@footnote{This example will work for many types of file
2506 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2507 btrfs), the required steps may be different. For details, see the
2508 manual pages for @command{mkswap} and @command{swapon}.}:
2511 # This is 10 GiB of swap space. Adjust "count" to change the size.
2512 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2513 # For security, make the file readable and writable only by root.
2514 chmod 600 /mnt/swapfile
2515 mkswap /mnt/swapfile
2516 swapon /mnt/swapfile
2519 Note that if you have encrypted the root partition and created a swap
2520 file in its file system as described above, then the encryption also
2521 protects the swap file, just like any other file in that file system.
2523 @node Proceeding with the Installation
2524 @subsection Proceeding with the Installation
2526 With the target partitions ready and the target root mounted on
2527 @file{/mnt}, we're ready to go. First, run:
2530 herd start cow-store /mnt
2533 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2534 during the installation phase are written to the target disk on @file{/mnt}
2535 rather than kept in memory. This is necessary because the first phase of
2536 the @command{guix system init} command (see below) entails downloads or
2537 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2539 Next, you have to edit a file and
2540 provide the declaration of the operating system to be installed. To
2541 that end, the installation system comes with three text editors. We
2542 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2543 supports syntax highlighting and parentheses matching; other editors
2544 include GNU Zile (an Emacs clone), and
2545 nvi (a clone of the original BSD @command{vi} editor).
2546 We strongly recommend storing that file on the target root file system, say,
2547 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2548 configuration file once you have rebooted into the newly-installed system.
2550 @xref{Using the Configuration System}, for an overview of the
2551 configuration file. The example configurations discussed in that
2552 section are available under @file{/etc/configuration} in the
2553 installation image. Thus, to get started with a system configuration
2554 providing a graphical display server (a ``desktop'' system), you can run
2555 something along these lines:
2559 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2560 # nano /mnt/etc/config.scm
2563 You should pay attention to what your configuration file contains, and
2568 Make sure the @code{bootloader-configuration} form refers to the target
2569 you want to install GRUB on. It should mention @code{grub-bootloader} if
2570 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2571 for newer UEFI systems. For legacy systems, the @code{target} field
2572 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2573 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2574 currently mounted and a @code{file-system} entry is specified in your
2578 Be sure that your file system labels match the value of their respective
2579 @code{device} fields in your @code{file-system} configuration, assuming
2580 your @code{file-system} configuration uses the @code{file-system-label}
2581 procedure in its @code{device} field.
2584 If there are encrypted or RAID partitions, make sure to add a
2585 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2588 Once you are done preparing the configuration file, the new system must
2589 be initialized (remember that the target root file system is mounted
2593 guix system init /mnt/etc/config.scm /mnt
2597 This copies all the necessary files and installs GRUB on
2598 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2599 more information, @pxref{Invoking guix system}. This command may trigger
2600 downloads or builds of missing packages, which can take some time.
2602 Once that command has completed---and hopefully succeeded!---you can run
2603 @command{reboot} and boot into the new system. The @code{root} password
2604 in the new system is initially empty; other users' passwords need to be
2605 initialized by running the @command{passwd} command as @code{root},
2606 unless your configuration specifies otherwise
2607 (@pxref{user-account-password, user account passwords}).
2608 @xref{After System Installation}, for what's next!
2611 @node After System Installation
2612 @section After System Installation
2614 Success, you've now booted into Guix System! From then on, you can update the
2615 system whenever you want by running, say:
2619 sudo guix system reconfigure /etc/config.scm
2623 This builds a new system generation with the latest packages and services
2624 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2625 your system includes the latest security updates (@pxref{Security Updates}).
2627 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2629 @cindex sudo vs. @command{guix pull}
2630 Note that @command{sudo guix} runs your user's @command{guix} command and
2631 @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
2632 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2634 The difference matters here, because @command{guix pull} updates
2635 the @command{guix} command and package definitions only for the user it is run
2636 as. This means that if you choose to use @command{guix system reconfigure} in
2637 root's login shell, you'll need to @command{guix pull} separately.
2640 Now, @pxref{Getting Started}, and
2641 join us on @code{#guix} on the Freenode IRC network or on
2642 @email{guix-devel@@gnu.org} to share your experience!
2645 @node Installing Guix in a VM
2646 @section Installing Guix in a Virtual Machine
2648 @cindex virtual machine, Guix System installation
2649 @cindex virtual private server (VPS)
2650 @cindex VPS (virtual private server)
2651 If you'd like to install Guix System in a virtual machine (VM) or on a
2652 virtual private server (VPS) rather than on your beloved machine, this
2655 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2656 disk image, follow these steps:
2660 First, retrieve and decompress the Guix system installation image as
2661 described previously (@pxref{USB Stick and DVD Installation}).
2664 Create a disk image that will hold the installed system. To make a
2665 qcow2-formatted disk image, use the @command{qemu-img} command:
2668 qemu-img create -f qcow2 guix-system.img 50G
2671 The resulting file will be much smaller than 50 GB (typically less than
2672 1 MB), but it will grow as the virtualized storage device is filled up.
2675 Boot the USB installation image in an VM:
2678 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2679 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2680 -drive file=guix-system.img \
2681 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2684 @code{-enable-kvm} is optional, but significantly improves performance,
2685 @pxref{Running Guix in a VM}.
2688 You're now root in the VM, proceed with the installation process.
2689 @xref{Preparing for Installation}, and follow the instructions.
2692 Once installation is complete, you can boot the system that's on your
2693 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2696 @node Building the Installation Image
2697 @section Building the Installation Image
2699 @cindex installation image
2700 The installation image described above was built using the @command{guix
2701 system} command, specifically:
2704 guix system image -t iso9660 gnu/system/install.scm
2707 Have a look at @file{gnu/system/install.scm} in the source tree,
2708 and see also @ref{Invoking guix system} for more information
2709 about the installation image.
2711 @section Building the Installation Image for ARM Boards
2713 Many ARM boards require a specific variant of the
2714 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2716 If you build a disk image and the bootloader is not available otherwise
2717 (on another boot drive etc), it's advisable to build an image that
2718 includes the bootloader, specifically:
2721 guix system image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2724 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2725 board, a list of possible boards will be printed.
2727 @c *********************************************************************
2728 @node Getting Started
2729 @chapter Getting Started
2731 Presumably, you've reached this section because either you have
2732 installed Guix on top of another distribution (@pxref{Installation}), or
2733 you've installed the standalone Guix System (@pxref{System
2734 Installation}). It's time for you to get started using Guix and this
2735 section aims to help you do that and give you a feel of what it's like.
2737 Guix is about installing software, so probably the first thing you'll
2738 want to do is to actually look for software. Let's say you're looking
2739 for a text editor, you can run:
2742 guix search text editor
2745 This command shows you a number of matching @dfn{packages}, each time
2746 showing the package's name, version, a description, and additional info.
2747 Once you've found out the one you want to use, let's say Emacs (ah ha!),
2748 you can go ahead and install it (run this command as a regular user,
2749 @emph{no need for root privileges}!):
2756 You've installed your first package, congrats! The package is now
2757 visible in your default @dfn{profile}, @file{$HOME/.guix-profile}---a
2758 profile is a directory containing installed packages.
2759 In the process, you've
2760 probably noticed that Guix downloaded pre-built binaries; or, if you
2761 explicitly chose to @emph{not} use pre-built binaries, then probably
2762 Guix is still building software (@pxref{Substitutes}, for more info).
2764 Unless you're using Guix System, the @command{guix install} command must
2765 have printed this hint:
2768 hint: Consider setting the necessary environment variables by running:
2770 GUIX_PROFILE="$HOME/.guix-profile"
2771 . "$GUIX_PROFILE/etc/profile"
2773 Alternately, see `guix package --search-paths -p "$HOME/.guix-profile"'.
2776 Indeed, you must now tell your shell where @command{emacs} and other
2777 programs installed with Guix are to be found. Pasting the two lines
2778 above will do just that: it will add
2779 @code{$HOME/.guix-profile/bin}---which is where the installed package
2780 is---to the @code{PATH} environment variable. You can paste these two
2781 lines in your shell so they take effect right away, but more importantly
2782 you should add them to @file{~/.bash_profile} (or equivalent file if you
2783 do not use Bash) so that environment variables are set next time you
2784 spawn a shell. You only need to do this once and other search paths
2785 environment variables will be taken care of similarly---e.g., if you
2786 eventually install @code{python} and Python libraries, @code{PYTHONPATH}
2789 You can go on installing packages at your will. To list installed
2793 guix package --list-installed
2796 To remove a package, you would unsurprisingly run @command{guix remove}.
2797 A distinguishing feature is the ability to @dfn{roll back} any operation
2798 you made---installation, removal, upgrade---by simply typing:
2801 guix package --roll-back
2804 This is because each operation is in fact a @dfn{transaction} that
2805 creates a new @dfn{generation}. These generations and the difference
2806 between them can be displayed by running:
2809 guix package --list-generations
2812 Now you know the basics of package management!
2814 @quotation Going further
2815 @xref{Package Management}, for more about package management. You may
2816 like @dfn{declarative} package management with @command{guix package
2817 --manifest}, managing separate @dfn{profiles} with @option{--profile},
2818 deleting old generations, collecting garbage, and other nifty features
2819 that will come in handy as you become more familiar with Guix. If you
2820 are a developer, @pxref{Development} for additional tools. And if
2821 you're curious, @pxref{Features}, to peek under the hood.
2824 Once you've installed a set of packages, you will want to periodically
2825 @emph{upgrade} them to the latest and greatest version. To do that, you
2826 will first pull the latest revision of Guix and its package collection:
2832 The end result is a new @command{guix} command, under
2833 @file{~/.config/guix/current/bin}. Unless you're on Guix System, the
2834 first time you run @command{guix pull}, be sure to follow the hint that
2835 the command prints and, similar to what we saw above, paste these two
2836 lines in your terminal and @file{.bash_profile}:
2839 GUIX_PROFILE="$HOME/.config/guix/current"
2840 . "$GUIX_PROFILE/etc/profile"
2844 You must also instruct your shell to point to this new @command{guix}:
2850 At this point, you're running a brand new Guix. You can thus go ahead
2851 and actually upgrade all the packages you previously installed:
2857 As you run this command, you will see that binaries are downloaded (or
2858 perhaps some packages are built), and eventually you end up with the
2859 upgraded packages. Should one of these upgraded packages not be to your
2860 liking, remember you can always roll back!
2862 You can display the exact revision of Guix you're currently using by
2869 The information it displays is @emph{all it takes to reproduce the exact
2870 same Guix}, be it at a different point in time or on a different
2873 @quotation Going further
2874 @xref{Invoking guix pull}, for more information. @xref{Channels}, on
2875 how to specify additional @dfn{channels} to pull packages from, how to
2876 replicate Guix, and more. You may also find @command{time-machine}
2877 handy (@pxref{Invoking guix time-machine}).
2880 If you installed Guix System, one of the first things you'll want to do
2881 is to upgrade your system. Once you've run @command{guix pull} to get
2882 the latest Guix, you can upgrade the system like this:
2885 sudo guix system reconfigure /etc/config.scm
2888 Upon completion, the system runs the latest versions of its software
2889 packages. When you eventually reboot, you'll notice a sub-menu in the
2890 bootloader that reads ``Old system generations'': it's what allows you
2891 to boot @emph{an older generation of your system}, should the latest
2892 generation be ``broken'' or otherwise unsatisfying. Just like for
2893 packages, you can always @emph{roll back} to a previous generation
2894 @emph{of the whole system}:
2897 sudo guix system roll-back
2900 There are many things you'll probably want to tweak on your system:
2901 adding new user accounts, adding new system services, fiddling with the
2902 configuration of those services, etc. The system configuration is
2903 @emph{entirely} described in the @file{/etc/config.scm} file.
2904 @xref{Using the Configuration System}, to learn how to change it.
2906 Now you know enough to get started!
2908 @quotation Resources
2909 The rest of this manual provides a reference for all things Guix. Here
2910 are some additional resources you may find useful:
2914 @xref{Top,,, guix-cookbook, The GNU Guix Cookbook}, for a list of
2915 ``how-to'' style of recipes for a variety of applications.
2918 The @uref{https://guix.gnu.org/guix-refcard.pdf, GNU Guix Reference
2919 Card} lists in two pages most of the commands and options you'll ever
2923 The web site contains @uref{https://guix.gnu.org/en/videos/,
2924 instructional videos} covering topics such as everyday use of Guix, how
2925 to get help, and how to become a contributor.
2928 @xref{Documentation}, to learn how to access documentation on your
2932 We hope you will enjoy Guix as much as the community enjoys building it!
2935 @c *********************************************************************
2936 @node Package Management
2937 @chapter Package Management
2940 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2941 remove software packages, without having to know about their build
2942 procedures or dependencies. Guix also goes beyond this obvious set of
2945 This chapter describes the main features of Guix, as well as the
2946 package management tools it provides. Along with the command-line
2947 interface described below (@pxref{Invoking guix package, @code{guix
2948 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2949 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2950 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2954 guix install emacs-guix
2958 * Features:: How Guix will make your life brighter.
2959 * Invoking guix package:: Package installation, removal, etc.
2960 * Substitutes:: Downloading pre-built binaries.
2961 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2962 * Invoking guix gc:: Running the garbage collector.
2963 * Invoking guix pull:: Fetching the latest Guix and distribution.
2964 * Invoking guix time-machine:: Running an older revision of Guix.
2965 * Inferiors:: Interacting with another revision of Guix.
2966 * Invoking guix describe:: Display information about your Guix revision.
2967 * Invoking guix archive:: Exporting and importing store files.
2973 Here we assume you've already made your first steps with Guix
2974 (@pxref{Getting Started}) and would like to get an overview about what's
2975 going on under the hood.
2977 When using Guix, each package ends up in the @dfn{package store}, in its
2978 own directory---something that resembles
2979 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2981 Instead of referring to these directories, users have their own
2982 @dfn{profile}, which points to the packages that they actually want to
2983 use. These profiles are stored within each user's home directory, at
2984 @code{$HOME/.guix-profile}.
2986 For example, @code{alice} installs GCC 4.7.2. As a result,
2987 @file{/home/alice/.guix-profile/bin/gcc} points to
2988 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2989 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2990 simply continues to point to
2991 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2992 coexist on the same system without any interference.
2994 The @command{guix package} command is the central tool to manage
2995 packages (@pxref{Invoking guix package}). It operates on the per-user
2996 profiles, and can be used @emph{with normal user privileges}.
2998 @cindex transactions
2999 The command provides the obvious install, remove, and upgrade
3000 operations. Each invocation is actually a @emph{transaction}: either
3001 the specified operation succeeds, or nothing happens. Thus, if the
3002 @command{guix package} process is terminated during the transaction,
3003 or if a power outage occurs during the transaction, then the user's
3004 profile remains in its previous state, and remains usable.
3006 In addition, any package transaction may be @emph{rolled back}. So, if,
3007 for example, an upgrade installs a new version of a package that turns
3008 out to have a serious bug, users may roll back to the previous instance
3009 of their profile, which was known to work well. Similarly, the global
3010 system configuration on Guix is subject to
3011 transactional upgrades and roll-back
3012 (@pxref{Using the Configuration System}).
3014 All packages in the package store may be @emph{garbage-collected}.
3015 Guix can determine which packages are still referenced by user
3016 profiles, and remove those that are provably no longer referenced
3017 (@pxref{Invoking guix gc}). Users may also explicitly remove old
3018 generations of their profile so that the packages they refer to can be
3021 @cindex reproducibility
3022 @cindex reproducible builds
3023 Guix takes a @dfn{purely functional} approach to package
3024 management, as described in the introduction (@pxref{Introduction}).
3025 Each @file{/gnu/store} package directory name contains a hash of all the
3026 inputs that were used to build that package---compiler, libraries, build
3027 scripts, etc. This direct correspondence allows users to make sure a
3028 given package installation matches the current state of their
3029 distribution. It also helps maximize @dfn{build reproducibility}:
3030 thanks to the isolated build environments that are used, a given build
3031 is likely to yield bit-identical files when performed on different
3032 machines (@pxref{Invoking guix-daemon, container}).
3035 This foundation allows Guix to support @dfn{transparent binary/source
3036 deployment}. When a pre-built binary for a @file{/gnu/store} item is
3037 available from an external source---a @dfn{substitute}, Guix just
3038 downloads it and unpacks it;
3039 otherwise, it builds the package from source, locally
3040 (@pxref{Substitutes}). Because build results are usually bit-for-bit
3041 reproducible, users do not have to trust servers that provide
3042 substitutes: they can force a local build and @emph{challenge} providers
3043 (@pxref{Invoking guix challenge}).
3045 Control over the build environment is a feature that is also useful for
3046 developers. The @command{guix environment} command allows developers of
3047 a package to quickly set up the right development environment for their
3048 package, without having to manually install the dependencies of the
3049 package into their profile (@pxref{Invoking guix environment}).
3051 @cindex replication, of software environments
3052 @cindex provenance tracking, of software artifacts
3053 All of Guix and its package definitions is version-controlled, and
3054 @command{guix pull} allows you to ``travel in time'' on the history of Guix
3055 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
3056 Guix instance on a different machine or at a later point in time, which in
3057 turn allows you to @emph{replicate complete software environments}, while
3058 retaining precise @dfn{provenance tracking} of the software.
3060 @node Invoking guix package
3061 @section Invoking @command{guix package}
3063 @cindex installing packages
3064 @cindex removing packages
3065 @cindex package installation
3066 @cindex package removal
3068 The @command{guix package} command is the tool that allows users to
3069 install, upgrade, and remove packages, as well as rolling back to
3070 previous configurations. These operations work on a user
3071 @dfn{profile}---a directory of installed packages. Each user has a
3072 default profile in @file{$HOME/.guix-profile}.
3073 The command operates only on the user's own profile,
3074 and works with normal user privileges (@pxref{Features}). Its syntax
3078 guix package @var{options}
3081 @cindex transactions
3082 Primarily, @var{options} specifies the operations to be performed during
3083 the transaction. Upon completion, a new profile is created, but
3084 previous @dfn{generations} of the profile remain available, should the user
3087 For example, to remove @code{lua} and install @code{guile} and
3088 @code{guile-cairo} in a single transaction:
3091 guix package -r lua -i guile guile-cairo
3094 @cindex aliases, for @command{guix package}
3095 For your convenience, we also provide the following aliases:
3099 @command{guix search} is an alias for @command{guix package -s},
3101 @command{guix install} is an alias for @command{guix package -i},
3103 @command{guix remove} is an alias for @command{guix package -r},
3105 @command{guix upgrade} is an alias for @command{guix package -u},
3107 and @command{guix show} is an alias for @command{guix package --show=}.
3110 These aliases are less expressive than @command{guix package} and provide
3111 fewer options, so in some cases you'll probably want to use @command{guix
3114 @command{guix package} also supports a @dfn{declarative approach}
3115 whereby the user specifies the exact set of packages to be available and
3116 passes it @i{via} the @option{--manifest} option
3117 (@pxref{profile-manifest, @option{--manifest}}).
3120 For each user, a symlink to the user's default profile is automatically
3121 created in @file{$HOME/.guix-profile}. This symlink always points to the
3122 current generation of the user's default profile. Thus, users can add
3123 @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
3124 variable, and so on.
3125 @cindex search paths
3126 If you are not using Guix System, consider adding the
3127 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
3128 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
3129 shells get all the right environment variable definitions:
3132 GUIX_PROFILE="$HOME/.guix-profile" ; \
3133 source "$GUIX_PROFILE/etc/profile"
3136 In a multi-user setup, user profiles are stored in a place registered as
3137 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
3138 to (@pxref{Invoking guix gc}). That directory is normally
3139 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
3140 @var{localstatedir} is the value passed to @code{configure} as
3141 @option{--localstatedir}, and @var{user} is the user name. The
3142 @file{per-user} directory is created when @command{guix-daemon} is
3143 started, and the @var{user} sub-directory is created by @command{guix
3146 The @var{options} can be among the following:
3150 @item --install=@var{package} @dots{}
3151 @itemx -i @var{package} @dots{}
3152 Install the specified @var{package}s.
3154 Each @var{package} may specify either a simple package name, such as
3155 @code{guile}, or a package name followed by an at-sign and version number,
3156 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
3157 case, the newest version prefixed by @code{1.8} is selected).
3159 If no version number is specified, the
3160 newest available version will be selected. In addition, @var{package}
3161 may contain a colon, followed by the name of one of the outputs of the
3162 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
3163 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
3164 name (and optionally version) are searched for among the GNU
3165 distribution modules (@pxref{Package Modules}).
3167 @cindex propagated inputs
3168 Sometimes packages have @dfn{propagated inputs}: these are dependencies
3169 that automatically get installed along with the required package
3170 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
3171 @code{package} objects}, for information about propagated inputs in
3172 package definitions).
3174 @anchor{package-cmd-propagated-inputs}
3175 An example is the GNU MPC library: its C header files refer to those of
3176 the GNU MPFR library, which in turn refer to those of the GMP library.
3177 Thus, when installing MPC, the MPFR and GMP libraries also get installed
3178 in the profile; removing MPC also removes MPFR and GMP---unless they had
3179 also been explicitly installed by the user.
3181 Besides, packages sometimes rely on the definition of environment
3182 variables for their search paths (see explanation of
3183 @option{--search-paths} below). Any missing or possibly incorrect
3184 environment variable definitions are reported here.
3186 @item --install-from-expression=@var{exp}
3188 Install the package @var{exp} evaluates to.
3190 @var{exp} must be a Scheme expression that evaluates to a
3191 @code{<package>} object. This option is notably useful to disambiguate
3192 between same-named variants of a package, with expressions such as
3193 @code{(@@ (gnu packages base) guile-final)}.
3195 Note that this option installs the first output of the specified
3196 package, which may be insufficient when needing a specific output of a
3197 multiple-output package.
3199 @item --install-from-file=@var{file}
3200 @itemx -f @var{file}
3201 Install the package that the code within @var{file} evaluates to.
3203 As an example, @var{file} might contain a definition like this
3204 (@pxref{Defining Packages}):
3207 @include package-hello.scm
3210 Developers may find it useful to include such a @file{guix.scm} file
3211 in the root of their project source tree that can be used to test
3212 development snapshots and create reproducible development environments
3213 (@pxref{Invoking guix environment}).
3215 The @var{file} may also contain a JSON representation of one or more
3216 package definitions. Running @code{guix package -f} on
3217 @file{hello.json} with the following contents would result in installing
3218 the package @code{greeter} after building @code{myhello}:
3221 @verbatiminclude package-hello.json
3224 @item --remove=@var{package} @dots{}
3225 @itemx -r @var{package} @dots{}
3226 Remove the specified @var{package}s.
3228 As for @option{--install}, each @var{package} may specify a version number
3229 and/or output name in addition to the package name. For instance,
3230 @samp{-r glibc:debug} would remove the @code{debug} output of
3233 @item --upgrade[=@var{regexp} @dots{}]
3234 @itemx -u [@var{regexp} @dots{}]
3235 @cindex upgrading packages
3236 Upgrade all the installed packages. If one or more @var{regexp}s are
3237 specified, upgrade only installed packages whose name matches a
3238 @var{regexp}. Also see the @option{--do-not-upgrade} option below.
3240 Note that this upgrades package to the latest version of packages found
3241 in the distribution currently installed. To update your distribution,
3242 you should regularly run @command{guix pull} (@pxref{Invoking guix
3245 @cindex package transformations, upgrades
3246 When upgrading, package transformations that were originally applied
3247 when creating the profile are automatically re-applied (@pxref{Package
3248 Transformation Options}). For example, assume you first installed Emacs
3249 from the tip of its development branch with:
3252 guix install emacs-next --with-branch=emacs-next=master
3255 Next time you run @command{guix upgrade}, Guix will again pull the tip
3256 of the Emacs development branch and build @code{emacs-next} from that
3259 Note that transformation options such as @option{--with-branch} and
3260 @option{--with-source} depend on external state; it is up to you to
3261 ensure that they work as expected. You can also discard a
3262 transformations that apply to a package by running:
3265 guix install @var{package}
3268 @item --do-not-upgrade[=@var{regexp} @dots{}]
3269 When used together with the @option{--upgrade} option, do @emph{not}
3270 upgrade any packages whose name matches a @var{regexp}. For example, to
3271 upgrade all packages in the current profile except those containing the
3272 substring ``emacs'':
3275 $ guix package --upgrade . --do-not-upgrade emacs
3278 @item @anchor{profile-manifest}--manifest=@var{file}
3279 @itemx -m @var{file}
3280 @cindex profile declaration
3281 @cindex profile manifest
3282 Create a new generation of the profile from the manifest object
3283 returned by the Scheme code in @var{file}. This option can be repeated
3284 several times, in which case the manifests are concatenated.
3286 This allows you to @emph{declare} the profile's contents rather than
3287 constructing it through a sequence of @option{--install} and similar
3288 commands. The advantage is that @var{file} can be put under version
3289 control, copied to different machines to reproduce the same profile, and
3292 @c FIXME: Add reference to (guix profile) documentation when available.
3293 @var{file} must return a @dfn{manifest} object, which is roughly a list
3296 @findex packages->manifest
3298 (use-package-modules guile emacs)
3303 ;; Use a specific package output.
3304 (list guile-2.0 "debug")))
3307 @findex specifications->manifest
3308 In this example we have to know which modules define the @code{emacs}
3309 and @code{guile-2.0} variables to provide the right
3310 @code{use-package-modules} line, which can be cumbersome. We can
3311 instead provide regular package specifications and let
3312 @code{specifications->manifest} look up the corresponding package
3316 (specifications->manifest
3317 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
3320 @xref{export-manifest, @option{--export-manifest}}, to learn how to
3321 obtain a manifest file from an existing profile.
3324 @cindex rolling back
3325 @cindex undoing transactions
3326 @cindex transactions, undoing
3327 Roll back to the previous @dfn{generation} of the profile---i.e., undo
3328 the last transaction.
3330 When combined with options such as @option{--install}, roll back occurs
3331 before any other actions.
3333 When rolling back from the first generation that actually contains
3334 installed packages, the profile is made to point to the @dfn{zeroth
3335 generation}, which contains no files apart from its own metadata.
3337 After having rolled back, installing, removing, or upgrading packages
3338 overwrites previous future generations. Thus, the history of the
3339 generations in a profile is always linear.
3341 @item --switch-generation=@var{pattern}
3342 @itemx -S @var{pattern}
3344 Switch to a particular generation defined by @var{pattern}.
3346 @var{pattern} may be either a generation number or a number prefixed
3347 with ``+'' or ``-''. The latter means: move forward/backward by a
3348 specified number of generations. For example, if you want to return to
3349 the latest generation after @option{--roll-back}, use
3350 @option{--switch-generation=+1}.
3352 The difference between @option{--roll-back} and
3353 @option{--switch-generation=-1} is that @option{--switch-generation} will
3354 not make a zeroth generation, so if a specified generation does not
3355 exist, the current generation will not be changed.
3357 @item --search-paths[=@var{kind}]
3358 @cindex search paths
3359 Report environment variable definitions, in Bash syntax, that may be
3360 needed in order to use the set of installed packages. These environment
3361 variables are used to specify @dfn{search paths} for files used by some
3362 of the installed packages.
3364 For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
3365 environment variables to be defined so it can look for headers and
3366 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
3367 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
3368 library are installed in the profile, then @option{--search-paths} will
3369 suggest setting these variables to @file{@var{profile}/include} and
3370 @file{@var{profile}/lib}, respectively.
3372 The typical use case is to define these environment variables in the
3376 $ eval `guix package --search-paths`
3379 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
3380 meaning that the returned environment variable definitions will either
3381 be exact settings, or prefixes or suffixes of the current value of these
3382 variables. When omitted, @var{kind} defaults to @code{exact}.
3384 This option can also be used to compute the @emph{combined} search paths
3385 of several profiles. Consider this example:
3388 $ guix package -p foo -i guile
3389 $ guix package -p bar -i guile-json
3390 $ guix package -p foo -p bar --search-paths
3393 The last command above reports about the @env{GUILE_LOAD_PATH}
3394 variable, even though, taken individually, neither @file{foo} nor
3395 @file{bar} would lead to that recommendation.
3398 @cindex profile, choosing
3399 @item --profile=@var{profile}
3400 @itemx -p @var{profile}
3401 Use @var{profile} instead of the user's default profile.
3403 @var{profile} must be the name of a file that will be created upon
3404 completion. Concretely, @var{profile} will be a mere symbolic link
3405 (``symlink'') pointing to the actual profile where packages are
3409 $ guix install hello -p ~/code/my-profile
3411 $ ~/code/my-profile/bin/hello
3415 All it takes to get rid of the profile is to remove this symlink and its
3416 siblings that point to specific generations:
3419 $ rm ~/code/my-profile ~/code/my-profile-*-link
3422 @item --list-profiles
3423 List all the user's profiles:
3426 $ guix package --list-profiles
3427 /home/charlie/.guix-profile
3428 /home/charlie/code/my-profile
3429 /home/charlie/code/devel-profile
3430 /home/charlie/tmp/test
3433 When running as root, list all the profiles of all the users.
3435 @cindex collisions, in a profile
3436 @cindex colliding packages in profiles
3437 @cindex profile collisions
3438 @item --allow-collisions
3439 Allow colliding packages in the new profile. Use at your own risk!
3441 By default, @command{guix package} reports as an error @dfn{collisions}
3442 in the profile. Collisions happen when two or more different versions
3443 or variants of a given package end up in the profile.
3446 Use the bootstrap Guile to build the profile. This option is only
3447 useful to distribution developers.
3451 In addition to these actions, @command{guix package} supports the
3452 following options to query the current state of a profile, or the
3453 availability of packages:
3457 @item --search=@var{regexp}
3458 @itemx -s @var{regexp}
3459 @anchor{guix-search}
3460 @cindex searching for packages
3461 List the available packages whose name, synopsis, or description matches
3462 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3463 Print all the metadata of matching packages in
3464 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3465 GNU recutils manual}).
3467 This allows specific fields to be extracted using the @command{recsel}
3468 command, for instance:
3471 $ guix package -s malloc | recsel -p name,version,relevance
3485 Similarly, to show the name of all the packages available under the
3486 terms of the GNU@tie{}LGPL version 3:
3489 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3496 It is also possible to refine search results using several @code{-s} flags to
3497 @command{guix package}, or several arguments to @command{guix search}. For
3498 example, the following command returns a list of board games (this time using
3499 the @command{guix search} alias):
3502 $ guix search '\<board\>' game | recsel -p name
3507 If we were to omit @code{-s game}, we would also get software packages
3508 that deal with printed circuit boards; removing the angle brackets
3509 around @code{board} would further add packages that have to do with
3512 And now for a more elaborate example. The following command searches
3513 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3514 libraries, and prints the name and synopsis of the matching packages:
3517 $ guix search crypto library | \
3518 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3522 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3523 information on @dfn{selection expressions} for @code{recsel -e}.
3525 @item --show=@var{package}
3526 Show details about @var{package}, taken from the list of available packages, in
3527 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3531 $ guix package --show=python | recsel -p name,version
3539 You may also specify the full name of a package to only get details about a
3540 specific version of it (this time using the @command{guix show} alias):
3542 $ guix show python@@3.4 | recsel -p name,version
3549 @item --list-installed[=@var{regexp}]
3550 @itemx -I [@var{regexp}]
3551 List the currently installed packages in the specified profile, with the
3552 most recently installed packages shown last. When @var{regexp} is
3553 specified, list only installed packages whose name matches @var{regexp}.
3555 For each installed package, print the following items, separated by
3556 tabs: the package name, its version string, the part of the package that
3557 is installed (for instance, @code{out} for the default output,
3558 @code{include} for its headers, etc.), and the path of this package in
3561 @item --list-available[=@var{regexp}]
3562 @itemx -A [@var{regexp}]
3563 List packages currently available in the distribution for this system
3564 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3565 available packages whose name matches @var{regexp}.
3567 For each package, print the following items separated by tabs: its name,
3568 its version string, the parts of the package (@pxref{Packages with
3569 Multiple Outputs}), and the source location of its definition.
3571 @item --list-generations[=@var{pattern}]
3572 @itemx -l [@var{pattern}]
3574 Return a list of generations along with their creation dates; for each
3575 generation, show the installed packages, with the most recently
3576 installed packages shown last. Note that the zeroth generation is never
3579 For each installed package, print the following items, separated by
3580 tabs: the name of a package, its version string, the part of the package
3581 that is installed (@pxref{Packages with Multiple Outputs}), and the
3582 location of this package in the store.
3584 When @var{pattern} is used, the command returns only matching
3585 generations. Valid patterns include:
3588 @item @emph{Integers and comma-separated integers}. Both patterns denote
3589 generation numbers. For instance, @option{--list-generations=1} returns
3592 And @option{--list-generations=1,8,2} outputs three generations in the
3593 specified order. Neither spaces nor trailing commas are allowed.
3595 @item @emph{Ranges}. @option{--list-generations=2..9} prints the
3596 specified generations and everything in between. Note that the start of
3597 a range must be smaller than its end.
3599 It is also possible to omit the endpoint. For example,
3600 @option{--list-generations=2..}, returns all generations starting from the
3603 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3604 or months by passing an integer along with the first letter of the
3605 duration. For example, @option{--list-generations=20d} lists generations
3606 that are up to 20 days old.
3609 @item --delete-generations[=@var{pattern}]
3610 @itemx -d [@var{pattern}]
3611 When @var{pattern} is omitted, delete all generations except the current
3614 This command accepts the same patterns as @option{--list-generations}.
3615 When @var{pattern} is specified, delete the matching generations. When
3616 @var{pattern} specifies a duration, generations @emph{older} than the
3617 specified duration match. For instance, @option{--delete-generations=1m}
3618 deletes generations that are more than one month old.
3620 If the current generation matches, it is @emph{not} deleted. Also, the
3621 zeroth generation is never deleted.
3623 Note that deleting generations prevents rolling back to them.
3624 Consequently, this command must be used with care.
3626 @cindex manifest, exporting
3627 @anchor{export-manifest}
3628 @item --export-manifest
3629 Write to standard output a manifest suitable for @option{--manifest}
3630 corresponding to the chosen profile(s).
3632 This option is meant to help you migrate from the ``imperative''
3633 operating mode---running @command{guix install}, @command{guix upgrade},
3634 etc.---to the declarative mode that @option{--manifest} offers.
3636 Be aware that the resulting manifest @emph{approximates} what your
3637 profile actually contains; for instance, depending on how your profile
3638 was created, it can refer to packages or package versions that are not
3639 exactly what you specified.
3641 Keep in mind that a manifest is purely symbolic: it only contains
3642 package names and possibly versions, and their meaning varies over time.
3643 If you wish to ``pin'' channels to the revisions that were used to build
3644 the profile(s), see @option{--export-channels} below.
3646 @cindex pinning, channel revisions of a profile
3647 @item --export-channels
3648 Write to standard output the list of channels used by the chosen
3649 profile(s), in a format suitable for @command{guix pull --channels} or
3650 @command{guix time-machine --channels} (@pxref{Channels}).
3652 Together with @option{--export-manifest}, this option provides
3653 information allowing you to replicate the current profile
3654 (@pxref{Replicating Guix}).
3656 However, note that the output of this command @emph{approximates} what
3657 was actually used to build this profile. In particular, a single
3658 profile might have been built from several different revisions of the
3659 same channel. In that case, @option{--export-manifest} chooses the last
3660 one and writes the list of other revisions in a comment. If you really
3661 need to pick packages from different channel revisions, you can use
3662 inferiors in your manifest to do so (@pxref{Inferiors}).
3664 Together with @option{--export-manifest}, this is a good starting point
3665 if you are willing to migrate from the ``imperative'' model to the fully
3666 declarative model consisting of a manifest file along with a channels
3667 file pinning the exact channel revision(s) you want.
3670 Finally, since @command{guix package} may actually start build
3671 processes, it supports all the common build options (@pxref{Common Build
3672 Options}). It also supports package transformation options, such as
3673 @option{--with-source}, and preserves them across upgrades
3674 (@pxref{Package Transformation Options}).
3677 @section Substitutes
3680 @cindex pre-built binaries
3681 Guix supports transparent source/binary deployment, which means that it
3682 can either build things locally, or download pre-built items from a
3683 server, or both. We call these pre-built items @dfn{substitutes}---they
3684 are substitutes for local build results. In many cases, downloading a
3685 substitute is much faster than building things locally.
3687 Substitutes can be anything resulting from a derivation build
3688 (@pxref{Derivations}). Of course, in the common case, they are
3689 pre-built package binaries, but source tarballs, for instance, which
3690 also result from derivation builds, can be available as substitutes.
3693 * Official Substitute Server:: One particular source of substitutes.
3694 * Substitute Server Authorization:: How to enable or disable substitutes.
3695 * Getting Substitutes from Other Servers:: Substitute diversity.
3696 * Substitute Authentication:: How Guix verifies substitutes.
3697 * Proxy Settings:: How to get substitutes via proxy.
3698 * Substitution Failure:: What happens when substitution fails.
3699 * On Trusting Binaries:: How can you trust that binary blob?
3702 @node Official Substitute Server
3703 @subsection Official Substitute Server
3706 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3707 that builds packages from Guix continuously for some
3708 architectures, and makes them available as substitutes. This is the
3709 default source of substitutes; it 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 farm 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}} or a
3740 must add its public key to the access control list (ACL) of archive
3741 imports, using the @command{guix archive} command (@pxref{Invoking guix
3742 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3743 be compromised and to serve genuine substitutes.
3746 If you are using Guix System, you can skip this section: Guix System
3747 authorizes substitutes from @code{@value{SUBSTITUTE-SERVER}} by default.
3750 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3751 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3752 the installation prefix of Guix. If you installed Guix from source,
3753 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}.pub
3761 Once this is in place, the output of a command like @code{guix build}
3762 should change from something like:
3765 $ guix build emacs --dry-run
3766 The following derivations would be built:
3767 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3768 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3769 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3770 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3778 $ guix build emacs --dry-run
3779 112.3 MB would be downloaded:
3780 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3781 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3782 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3783 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3788 The text changed from ``The following derivations would be built'' to
3789 ``112.3 MB would be downloaded''. This indicates that substitutes from
3790 @code{@value{SUBSTITUTE-SERVER}} are usable and will be downloaded, when
3791 possible, for future builds.
3793 @cindex substitutes, how to disable
3794 The substitute mechanism can be disabled globally by running
3795 @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
3796 guix-daemon}). It can also be disabled temporarily by passing the
3797 @option{--no-substitutes} option to @command{guix package},
3798 @command{guix build}, and other command-line tools.
3800 @node Getting Substitutes from Other Servers
3801 @subsection Getting Substitutes from Other Servers
3803 @cindex substitute servers, adding more
3804 Guix can look up and fetch substitutes from several servers. This is
3805 useful when you are using packages from additional channels for which
3806 the official server does not have substitutes but another server
3807 provides them. Another situation where this is useful is when you would
3808 prefer to download from your organization's substitute server, resorting
3809 to the official server only as a fallback or dismissing it altogether.
3811 You can give Guix a list of substitute server URLs and it will check
3812 them in the specified order. You also need to explicitly authorize the
3813 public keys of substitute servers to instruct Guix to accept the
3814 substitutes they sign.
3816 On Guix System, this is achieved by modifying the configuration of the
3817 @code{guix} service. Since the @code{guix} service is part of the
3818 default lists of services, @code{%base-services} and
3819 @code{%desktop-services}, you can use @code{modify-services} to change
3820 its configuration and add the URLs and substitute keys that you want
3821 (@pxref{Service Reference, @code{modify-services}}).
3823 As an example, suppose you want to fetch substitutes from
3824 @code{guix.example.org} and to authorize the signing key of that server,
3825 in addition to the default @code{@value{SUBSTITUTE-SERVER}}. The
3826 resulting operating system configuration will look something like:
3832 ;; Assume we're starting from '%desktop-services'. Replace it
3833 ;; with the list of services you're actually using.
3834 (modify-services %desktop-services
3835 (guix-service-type config =>
3839 (append (list "https://guix.example.org")
3840 %default-substitute-urls))
3842 (append (list (local-file "./key.pub"))
3843 %default-authorized-guix-keys)))))))
3846 This assumes that the file @file{key.pub} contains the signing key of
3847 @code{guix.example.org}. With this change in place in your operating
3848 system configuration file (say @file{/etc/config.scm}), you can
3849 reconfigure and restart the @code{guix-daemon} service or reboot so the
3850 changes take effect:
3853 $ sudo guix system reconfigure /etc/config.scm
3854 $ sudo herd restart guix-daemon
3857 If you're running Guix on a ``foreign distro'', you would instead take
3858 the following steps to get substitutes from additional servers:
3862 Edit the service configuration file for @code{guix-daemon}; when using
3863 systemd, this is normally
3864 @file{/etc/systemd/system/guix-daemon.service}. Add the
3865 @option{--substitute-urls} option on the @command{guix-daemon} command
3866 line and list the URLs of interest (@pxref{daemon-substitute-urls,
3867 @code{guix-daemon --substitute-urls}}):
3870 @dots{} --substitute-urls='https://guix.example.org https://@value{SUBSTITUTE-SERVER}'
3874 Restart the daemon. For systemd, it goes like this:
3877 systemctl daemon-reload
3878 systemctl restart guix-daemon.service
3882 Authorize the key of the new server (@pxref{Invoking guix archive}):
3885 guix archive --authorize < key.pub
3888 Again this assumes @file{key.pub} contains the public key that
3889 @code{guix.example.org} uses to sign substitutes.
3892 Now you're all set! Substitutes will be preferably taken from
3893 @code{https://guix.example.org}, using @code{@value{SUBSTITUTE-SERVER}}
3894 as a fallback. Of course you can list as many substitute servers as you
3895 like, with the caveat that substitute lookup can be slowed down if too
3896 many servers need to be contacted.
3898 Note that there are also situations where one may want to add the URL of
3899 a substitute server @emph{without} authorizing its key.
3900 @xref{Substitute Authentication}, to understand this fine point.
3902 @node Substitute Authentication
3903 @subsection Substitute Authentication
3905 @cindex digital signatures
3906 Guix detects and raises an error when attempting to use a substitute
3907 that has been tampered with. Likewise, it ignores substitutes that are
3908 not signed, or that are not signed by one of the keys listed in the ACL.
3910 There is one exception though: if an unauthorized server provides
3911 substitutes that are @emph{bit-for-bit identical} to those provided by
3912 an authorized server, then the unauthorized server becomes eligible for
3913 downloads. For example, assume we have chosen two substitute servers
3917 --substitute-urls="https://a.example.org https://b.example.org"
3921 @cindex reproducible builds
3922 If the ACL contains only the key for @samp{b.example.org}, and if
3923 @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
3924 then Guix will download substitutes from @samp{a.example.org} because it
3925 comes first in the list and can be considered a mirror of
3926 @samp{b.example.org}. In practice, independent build machines usually
3927 produce the same binaries, thanks to bit-reproducible builds (see
3930 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3931 (in other words, the server is not authenticated), contrary to what
3932 HTTPS clients such as Web browsers usually do. This is because Guix
3933 authenticates substitute information itself, as explained above, which
3934 is what we care about (whereas X.509 certificates are about
3935 authenticating bindings between domain names and public keys).
3937 @node Proxy Settings
3938 @subsection Proxy Settings
3942 Substitutes are downloaded over HTTP or HTTPS@. The @env{http_proxy} and
3943 @env{https_proxy} environment variables can be set in the environment of
3944 @command{guix-daemon} and are honored for downloads of substitutes.
3945 Note that the value of those environment variables in the environment
3946 where @command{guix build}, @command{guix package}, and other client
3947 commands are run has @emph{absolutely no effect}.
3949 @node Substitution Failure
3950 @subsection Substitution Failure
3952 Even when a substitute for a derivation is available, sometimes the
3953 substitution attempt will fail. This can happen for a variety of
3954 reasons: the substitute server might be offline, the substitute may
3955 recently have been deleted, the connection might have been interrupted,
3958 When substitutes are enabled and a substitute for a derivation is
3959 available, but the substitution attempt fails, Guix will attempt to
3960 build the derivation locally depending on whether or not
3961 @option{--fallback} was given (@pxref{fallback-option,, common build
3962 option @option{--fallback}}). Specifically, if @option{--fallback} was
3963 omitted, then no local build will be performed, and the derivation is
3964 considered to have failed. However, if @option{--fallback} was given,
3965 then Guix will attempt to build the derivation locally, and the success
3966 or failure of the derivation depends on the success or failure of the
3967 local build. Note that when substitutes are disabled or no substitute
3968 is available for the derivation in question, a local build will
3969 @emph{always} be performed, regardless of whether or not
3970 @option{--fallback} was given.
3972 To get an idea of how many substitutes are available right now, you can
3973 try running the @command{guix weather} command (@pxref{Invoking guix
3974 weather}). This command provides statistics on the substitutes provided
3977 @node On Trusting Binaries
3978 @subsection On Trusting Binaries
3980 @cindex trust, of pre-built binaries
3981 Today, each individual's control over their own computing is at the
3982 mercy of institutions, corporations, and groups with enough power and
3983 determination to subvert the computing infrastructure and exploit its
3984 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3985 convenient, we encourage users to also build on their own, or even run
3986 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3987 interesting target. One way to help is by publishing the software you
3988 build using @command{guix publish} so that others have one more choice
3989 of server to download substitutes from (@pxref{Invoking guix publish}).
3991 Guix has the foundations to maximize build reproducibility
3992 (@pxref{Features}). In most cases, independent builds of a given
3993 package or derivation should yield bit-identical results. Thus, through
3994 a diverse set of independent package builds, we can strengthen the
3995 integrity of our systems. The @command{guix challenge} command aims to
3996 help users assess substitute servers, and to assist developers in
3997 finding out about non-deterministic package builds (@pxref{Invoking guix
3998 challenge}). Similarly, the @option{--check} option of @command{guix
3999 build} allows users to check whether previously-installed substitutes
4000 are genuine by rebuilding them locally (@pxref{build-check,
4001 @command{guix build --check}}).
4003 In the future, we want Guix to have support to publish and retrieve
4004 binaries to/from other users, in a peer-to-peer fashion. If you would
4005 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
4007 @node Packages with Multiple Outputs
4008 @section Packages with Multiple Outputs
4010 @cindex multiple-output packages
4011 @cindex package outputs
4014 Often, packages defined in Guix have a single @dfn{output}---i.e., the
4015 source package leads to exactly one directory in the store. When running
4016 @command{guix install glibc}, one installs the default output of the
4017 GNU libc package; the default output is called @code{out}, but its name
4018 can be omitted as shown in this command. In this particular case, the
4019 default output of @code{glibc} contains all the C header files, shared
4020 libraries, static libraries, Info documentation, and other supporting
4023 Sometimes it is more appropriate to separate the various types of files
4024 produced from a single source package into separate outputs. For
4025 instance, the GLib C library (used by GTK+ and related packages)
4026 installs more than 20 MiB of reference documentation as HTML pages.
4027 To save space for users who do not need it, the documentation goes to a
4028 separate output, called @code{doc}. To install the main GLib output,
4029 which contains everything but the documentation, one would run:
4035 @cindex documentation
4036 The command to install its documentation is:
4039 guix install glib:doc
4042 Some packages install programs with different ``dependency footprints''.
4043 For instance, the WordNet package installs both command-line tools and
4044 graphical user interfaces (GUIs). The former depend solely on the C
4045 library, whereas the latter depend on Tcl/Tk and the underlying X
4046 libraries. In this case, we leave the command-line tools in the default
4047 output, whereas the GUIs are in a separate output. This allows users
4048 who do not need the GUIs to save space. The @command{guix size} command
4049 can help find out about such situations (@pxref{Invoking guix size}).
4050 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
4052 There are several such multiple-output packages in the GNU distribution.
4053 Other conventional output names include @code{lib} for libraries and
4054 possibly header files, @code{bin} for stand-alone programs, and
4055 @code{debug} for debugging information (@pxref{Installing Debugging
4056 Files}). The outputs of a packages are listed in the third column of
4057 the output of @command{guix package --list-available} (@pxref{Invoking
4061 @node Invoking guix gc
4062 @section Invoking @command{guix gc}
4064 @cindex garbage collector
4066 Packages that are installed, but not used, may be @dfn{garbage-collected}.
4067 The @command{guix gc} command allows users to explicitly run the garbage
4068 collector to reclaim space from the @file{/gnu/store} directory. It is
4069 the @emph{only} way to remove files from @file{/gnu/store}---removing
4070 files or directories manually may break it beyond repair!
4073 @cindex garbage collector roots
4074 The garbage collector has a set of known @dfn{roots}: any file under
4075 @file{/gnu/store} reachable from a root is considered @dfn{live} and
4076 cannot be deleted; any other file is considered @dfn{dead} and may be
4077 deleted. The set of garbage collector roots (``GC roots'' for short)
4078 includes default user profiles; by default, the symlinks under
4079 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
4080 added with @command{guix build --root}, for example (@pxref{Invoking
4081 guix build}). The @command{guix gc --list-roots} command lists them.
4083 Prior to running @code{guix gc --collect-garbage} to make space, it is
4084 often useful to remove old generations from user profiles; that way, old
4085 package builds referenced by those generations can be reclaimed. This
4086 is achieved by running @code{guix package --delete-generations}
4087 (@pxref{Invoking guix package}).
4089 Our recommendation is to run a garbage collection periodically, or when
4090 you are short on disk space. For instance, to guarantee that at least
4091 5@tie{}GB are available on your disk, simply run:
4097 It is perfectly safe to run as a non-interactive periodic job
4098 (@pxref{Scheduled Job Execution}, for how to set up such a job).
4099 Running @command{guix gc} with no arguments will collect as
4100 much garbage as it can, but that is often inconvenient: you may find
4101 yourself having to rebuild or re-download software that is ``dead'' from
4102 the GC viewpoint but that is necessary to build other pieces of
4103 software---e.g., the compiler tool chain.
4105 The @command{guix gc} command has three modes of operation: it can be
4106 used to garbage-collect any dead files (the default), to delete specific
4107 files (the @option{--delete} option), to print garbage-collector
4108 information, or for more advanced queries. The garbage collection
4109 options are as follows:
4112 @item --collect-garbage[=@var{min}]
4113 @itemx -C [@var{min}]
4114 Collect garbage---i.e., unreachable @file{/gnu/store} files and
4115 sub-directories. This is the default operation when no option is
4118 When @var{min} is given, stop once @var{min} bytes have been collected.
4119 @var{min} may be a number of bytes, or it may include a unit as a
4120 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
4121 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
4123 When @var{min} is omitted, collect all the garbage.
4125 @item --free-space=@var{free}
4126 @itemx -F @var{free}
4127 Collect garbage until @var{free} space is available under
4128 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
4129 as @code{500MiB}, as described above.
4131 When @var{free} or more is already available in @file{/gnu/store}, do
4132 nothing and exit immediately.
4134 @item --delete-generations[=@var{duration}]
4135 @itemx -d [@var{duration}]
4136 Before starting the garbage collection process, delete all the generations
4137 older than @var{duration}, for all the user profiles; when run as root, this
4138 applies to all the profiles @emph{of all the users}.
4140 For example, this command deletes all the generations of all your profiles
4141 that are older than 2 months (except generations that are current), and then
4142 proceeds to free space until at least 10 GiB are available:
4145 guix gc -d 2m -F 10G
4150 Attempt to delete all the store files and directories specified as
4151 arguments. This fails if some of the files are not in the store, or if
4152 they are still live.
4154 @item --list-failures
4155 List store items corresponding to cached build failures.
4157 This prints nothing unless the daemon was started with
4158 @option{--cache-failures} (@pxref{Invoking guix-daemon,
4159 @option{--cache-failures}}).
4162 List the GC roots owned by the user; when run as root, list @emph{all} the GC
4166 List store items in use by currently running processes. These store
4167 items are effectively considered GC roots: they cannot be deleted.
4169 @item --clear-failures
4170 Remove the specified store items from the failed-build cache.
4172 Again, this option only makes sense when the daemon is started with
4173 @option{--cache-failures}. Otherwise, it does nothing.
4176 Show the list of dead files and directories still present in the
4177 store---i.e., files and directories no longer reachable from any root.
4180 Show the list of live store files and directories.
4184 In addition, the references among existing store files can be queried:
4190 @cindex package dependencies
4191 List the references (respectively, the referrers) of store files given
4197 List the requisites of the store files passed as arguments. Requisites
4198 include the store files themselves, their references, and the references
4199 of these, recursively. In other words, the returned list is the
4200 @dfn{transitive closure} of the store files.
4202 @xref{Invoking guix size}, for a tool to profile the size of the closure
4203 of an element. @xref{Invoking guix graph}, for a tool to visualize
4204 the graph of references.
4208 Return the derivation(s) leading to the given store items
4209 (@pxref{Derivations}).
4211 For example, this command:
4214 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
4218 returns the @file{.drv} file(s) leading to the @code{emacs} package
4219 installed in your profile.
4221 Note that there may be zero matching @file{.drv} files, for instance
4222 because these files have been garbage-collected. There can also be more
4223 than one matching @file{.drv} due to fixed-output derivations.
4226 Lastly, the following options allow you to check the integrity of the
4227 store and to control disk usage.
4231 @item --verify[=@var{options}]
4232 @cindex integrity, of the store
4233 @cindex integrity checking
4234 Verify the integrity of the store.
4236 By default, make sure that all the store items marked as valid in the
4237 database of the daemon actually exist in @file{/gnu/store}.
4239 When provided, @var{options} must be a comma-separated list containing one
4240 or more of @code{contents} and @code{repair}.
4242 When passing @option{--verify=contents}, the daemon computes the
4243 content hash of each store item and compares it against its hash in the
4244 database. Hash mismatches are reported as data corruptions. Because it
4245 traverses @emph{all the files in the store}, this command can take a
4246 long time, especially on systems with a slow disk drive.
4248 @cindex repairing the store
4249 @cindex corruption, recovering from
4250 Using @option{--verify=repair} or @option{--verify=contents,repair}
4251 causes the daemon to try to repair corrupt store items by fetching
4252 substitutes for them (@pxref{Substitutes}). Because repairing is not
4253 atomic, and thus potentially dangerous, it is available only to the
4254 system administrator. A lightweight alternative, when you know exactly
4255 which items in the store are corrupt, is @command{guix build --repair}
4256 (@pxref{Invoking guix build}).
4259 @cindex deduplication
4260 Optimize the store by hard-linking identical files---this is
4261 @dfn{deduplication}.
4263 The daemon performs deduplication after each successful build or archive
4264 import, unless it was started with @option{--disable-deduplication}
4265 (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
4266 this option is primarily useful when the daemon was running with
4267 @option{--disable-deduplication}.
4271 @node Invoking guix pull
4272 @section Invoking @command{guix pull}
4274 @cindex upgrading Guix
4275 @cindex updating Guix
4276 @cindex @command{guix pull}
4278 @cindex security, @command{guix pull}
4279 @cindex authenticity, of code obtained with @command{guix pull}
4280 Packages are installed or upgraded to the latest version available in
4281 the distribution currently available on your local machine. To update
4282 that distribution, along with the Guix tools, you must run @command{guix
4283 pull}: the command downloads the latest Guix source code and package
4284 descriptions, and deploys it. Source code is downloaded from a
4285 @uref{https://git-scm.com, Git} repository, by default the official
4286 GNU@tie{}Guix repository, though this can be customized. @command{guix
4287 pull} ensures that the code it downloads is @emph{authentic} by
4288 verifying that commits are signed by Guix developers.
4290 Specifically, @command{guix pull} downloads code from the @dfn{channels}
4291 (@pxref{Channels}) specified by one of the followings, in this order:
4295 the @option{--channels} option;
4297 the user's @file{~/.config/guix/channels.scm} file;
4299 the system-wide @file{/etc/guix/channels.scm} file;
4301 the built-in default channels specified in the @code{%default-channels}
4305 On completion, @command{guix package} will use packages and package
4306 versions from this just-retrieved copy of Guix. Not only that, but all
4307 the Guix commands and Scheme modules will also be taken from that latest
4308 version. New @command{guix} sub-commands added by the update also
4311 Any user can update their Guix copy using @command{guix pull}, and the
4312 effect is limited to the user who ran @command{guix pull}. For
4313 instance, when user @code{root} runs @command{guix pull}, this has no
4314 effect on the version of Guix that user @code{alice} sees, and vice
4317 The result of running @command{guix pull} is a @dfn{profile} available
4318 under @file{~/.config/guix/current} containing the latest Guix. Thus,
4319 make sure to add it to the beginning of your search path so that you use
4320 the latest version, and similarly for the Info manual
4321 (@pxref{Documentation}):
4324 export PATH="$HOME/.config/guix/current/bin:$PATH"
4325 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
4328 The @option{--list-generations} or @option{-l} option lists past generations
4329 produced by @command{guix pull}, along with details about their provenance:
4333 Generation 1 Jun 10 2018 00:18:18
4335 repository URL: https://git.savannah.gnu.org/git/guix.git
4336 branch: origin/master
4337 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
4339 Generation 2 Jun 11 2018 11:02:49
4341 repository URL: https://git.savannah.gnu.org/git/guix.git
4342 branch: origin/master
4343 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
4344 2 new packages: keepalived, libnfnetlink
4345 6 packages upgraded: emacs-nix-mode@@2.0.4,
4346 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
4347 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
4349 Generation 3 Jun 13 2018 23:31:07 (current)
4351 repository URL: https://git.savannah.gnu.org/git/guix.git
4352 branch: origin/master
4353 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
4354 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
4355 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
4358 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
4359 describe the current status of Guix.
4361 This @code{~/.config/guix/current} profile works exactly like the profiles
4362 created by @command{guix package} (@pxref{Invoking guix package}). That
4363 is, you can list generations, roll back to the previous
4364 generation---i.e., the previous Guix---and so on:
4367 $ guix pull --roll-back
4368 switched from generation 3 to 2
4369 $ guix pull --delete-generations=1
4370 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4373 You can also use @command{guix package} (@pxref{Invoking guix package})
4374 to manage the profile by naming it explicitly:
4376 $ guix package -p ~/.config/guix/current --roll-back
4377 switched from generation 3 to 2
4378 $ guix package -p ~/.config/guix/current --delete-generations=1
4379 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4382 The @command{guix pull} command is usually invoked with no arguments,
4383 but it supports the following options:
4386 @item --url=@var{url}
4387 @itemx --commit=@var{commit}
4388 @itemx --branch=@var{branch}
4389 Download code for the @code{guix} channel from the specified @var{url}, at the
4390 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4391 string), or @var{branch}.
4393 @cindex @file{channels.scm}, configuration file
4394 @cindex configuration file for channels
4395 These options are provided for convenience, but you can also specify your
4396 configuration in the @file{~/.config/guix/channels.scm} file or using the
4397 @option{--channels} option (see below).
4399 @item --channels=@var{file}
4400 @itemx -C @var{file}
4401 Read the list of channels from @var{file} instead of
4402 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
4403 @var{file} must contain Scheme code that
4404 evaluates to a list of channel objects. @xref{Channels}, for more
4407 @cindex channel news
4410 Display the list of packages added or upgraded since the previous
4411 generation, as well as, occasionally, news written by channel authors
4412 for their users (@pxref{Channels, Writing Channel News}).
4414 The package information is the same as displayed upon @command{guix
4415 pull} completion, but without ellipses; it is also similar to the output
4416 of @command{guix pull -l} for the last generation (see below).
4418 @item --list-generations[=@var{pattern}]
4419 @itemx -l [@var{pattern}]
4420 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
4421 is provided, the subset of generations that match @var{pattern}.
4422 The syntax of @var{pattern} is the same as with @code{guix package
4423 --list-generations} (@pxref{Invoking guix package}).
4426 @cindex rolling back
4427 @cindex undoing transactions
4428 @cindex transactions, undoing
4429 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
4430 undo the last transaction.
4432 @item --switch-generation=@var{pattern}
4433 @itemx -S @var{pattern}
4435 Switch to a particular generation defined by @var{pattern}.
4437 @var{pattern} may be either a generation number or a number prefixed
4438 with ``+'' or ``-''. The latter means: move forward/backward by a
4439 specified number of generations. For example, if you want to return to
4440 the latest generation after @option{--roll-back}, use
4441 @option{--switch-generation=+1}.
4443 @item --delete-generations[=@var{pattern}]
4444 @itemx -d [@var{pattern}]
4445 When @var{pattern} is omitted, delete all generations except the current
4448 This command accepts the same patterns as @option{--list-generations}.
4449 When @var{pattern} is specified, delete the matching generations. When
4450 @var{pattern} specifies a duration, generations @emph{older} than the
4451 specified duration match. For instance, @option{--delete-generations=1m}
4452 deletes generations that are more than one month old.
4454 If the current generation matches, it is @emph{not} deleted.
4456 Note that deleting generations prevents rolling back to them.
4457 Consequently, this command must be used with care.
4459 @xref{Invoking guix describe}, for a way to display information about the
4460 current generation only.
4462 @item --profile=@var{profile}
4463 @itemx -p @var{profile}
4464 Use @var{profile} instead of @file{~/.config/guix/current}.
4468 Show which channel commit(s) would be used and what would be built or
4469 substituted but do not actually do it.
4471 @item --allow-downgrades
4472 Allow pulling older or unrelated revisions of channels than those
4475 @cindex downgrade attacks, protection against
4476 By default, @command{guix pull} protects against so-called ``downgrade
4477 attacks'' whereby the Git repository of a channel would be reset to an
4478 earlier or unrelated revision of itself, potentially leading you to
4479 install older, known-vulnerable versions of software packages.
4482 Make sure you understand its security implications before using
4483 @option{--allow-downgrades}.
4486 @item --disable-authentication
4487 Allow pulling channel code without authenticating it.
4489 @cindex authentication, of channel code
4490 By default, @command{guix pull} authenticates code downloaded from
4491 channels by verifying that its commits are signed by authorized
4492 developers, and raises an error if this is not the case. This option
4493 instructs it to not perform any such verification.
4496 Make sure you understand its security implications before using
4497 @option{--disable-authentication}.
4500 @item --system=@var{system}
4501 @itemx -s @var{system}
4502 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4503 the system type of the build host.
4506 Use the bootstrap Guile to build the latest Guix. This option is only
4507 useful to Guix developers.
4510 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
4511 repository and branch to pull from, as well as @emph{additional} repositories
4512 containing package modules that should be deployed. @xref{Channels}, for more
4515 In addition, @command{guix pull} supports all the common build options
4516 (@pxref{Common Build Options}).
4518 @node Invoking guix time-machine
4519 @section Invoking @command{guix time-machine}
4521 @cindex @command{guix time-machine}
4522 @cindex pinning, channels
4523 @cindex replicating Guix
4524 @cindex reproducibility, of Guix
4526 The @command{guix time-machine} command provides access to other
4527 revisions of Guix, for example to install older versions of packages,
4528 or to reproduce a computation in an identical environment. The revision
4529 of Guix to be used is defined by a commit or by a channel
4530 description file created by @command{guix describe}
4531 (@pxref{Invoking guix describe}).
4533 The general syntax is:
4536 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4539 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4540 @command{guix} command of the specified revision. The @var{options} that define
4541 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4544 @item --url=@var{url}
4545 @itemx --commit=@var{commit}
4546 @itemx --branch=@var{branch}
4547 Use the @code{guix} channel from the specified @var{url}, at the
4548 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4549 string), or @var{branch}.
4551 @item --channels=@var{file}
4552 @itemx -C @var{file}
4553 Read the list of channels from @var{file}. @var{file} must contain
4554 Scheme code that evaluates to a list of channel objects.
4555 @xref{Channels} for more information.
4558 As for @command{guix pull}, the absence of any options means that the
4559 latest commit on the master branch will be used. The command
4562 guix time-machine -- build hello
4565 will thus build the package @code{hello} as defined in the master branch,
4566 which is in general a newer revision of Guix than you have installed.
4567 Time travel works in both directions!
4569 Note that @command{guix time-machine} can trigger builds of channels and
4570 their dependencies, and these are controlled by the standard build
4571 options (@pxref{Common Build Options}).
4576 @c TODO: Remove this once we're more confident about API stability.
4578 The functionality described here is a ``technology preview'' as of version
4579 @value{VERSION}. As such, the interface is subject to change.
4583 @cindex composition of Guix revisions
4584 Sometimes you might need to mix packages from the revision of Guix you're
4585 currently running with packages available in a different revision of Guix.
4586 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4587 revisions in arbitrary ways.
4589 @cindex inferior packages
4590 Technically, an ``inferior'' is essentially a separate Guix process connected
4591 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4592 @code{(guix inferior)} module allows you to create inferiors and to
4593 communicate with them. It also provides a high-level interface to browse and
4594 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4596 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4597 to interact with a separate revision of Guix. For example, let's assume you
4598 want to install in your profile the current @code{guile} package, along with
4599 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4600 because the newer @code{guile-json} has an incompatible API and you want to
4601 run your code against the old API@. To do that, you could write a manifest for
4602 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4603 manifest, you would create an inferior for that old Guix revision you care
4604 about, and you would look up the @code{guile-json} package in the inferior:
4607 (use-modules (guix inferior) (guix channels)
4608 (srfi srfi-1)) ;for 'first'
4611 ;; This is the old revision from which we want to
4612 ;; extract guile-json.
4615 (url "https://git.savannah.gnu.org/git/guix.git")
4617 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4620 ;; An inferior representing the above revision.
4621 (inferior-for-channels channels))
4623 ;; Now create a manifest with the current "guile" package
4624 ;; and the old "guile-json" package.
4626 (list (first (lookup-inferior-packages inferior "guile-json"))
4627 (specification->package "guile")))
4630 On its first run, @command{guix package --manifest} might have to build the
4631 channel you specified before it can create the inferior; subsequent runs will
4632 be much faster because the Guix revision will be cached.
4634 The @code{(guix inferior)} module provides the following procedures to open an
4637 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4638 [#:cache-directory] [#:ttl]
4639 Return an inferior for @var{channels}, a list of channels. Use the cache at
4640 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4641 This procedure opens a new connection to the build daemon.
4643 As a side effect, this procedure may build or substitute binaries for
4644 @var{channels}, which can take time.
4647 @deffn {Scheme Procedure} open-inferior @var{directory} @
4648 [#:command "bin/guix"]
4649 Open the inferior Guix in @var{directory}, running
4650 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4651 the inferior could not be launched.
4654 @cindex inferior packages
4655 The procedures listed below allow you to obtain and manipulate inferior
4658 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4659 Return the list of packages known to @var{inferior}.
4662 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4664 Return the sorted list of inferior packages matching @var{name} in
4665 @var{inferior}, with highest version numbers first. If @var{version} is true,
4666 return only packages with a version number prefixed by @var{version}.
4669 @deffn {Scheme Procedure} inferior-package? @var{obj}
4670 Return true if @var{obj} is an inferior package.
4673 @deffn {Scheme Procedure} inferior-package-name @var{package}
4674 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4675 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4676 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4677 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4678 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4679 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4680 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4681 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4682 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4683 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4684 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4685 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4686 These procedures are the counterpart of package record accessors
4687 (@pxref{package Reference}). Most of them work by querying the inferior
4688 @var{package} comes from, so the inferior must still be live when you call
4692 Inferior packages can be used transparently like any other package or
4693 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4694 transparently handled by the @code{packages->manifest} procedure, which is
4695 commonly use in manifests (@pxref{Invoking guix package, the
4696 @option{--manifest} option of @command{guix package}}). Thus you can insert
4697 an inferior package pretty much anywhere you would insert a regular package:
4698 in manifests, in the @code{packages} field of your @code{operating-system}
4699 declaration, and so on.
4701 @node Invoking guix describe
4702 @section Invoking @command{guix describe}
4704 @cindex reproducibility
4705 @cindex replicating Guix
4706 Often you may want to answer questions like: ``Which revision of Guix am I
4707 using?'' or ``Which channels am I using?'' This is useful information in many
4708 situations: if you want to @emph{replicate} an environment on a different
4709 machine or user account, if you want to report a bug or to determine what
4710 change in the channels you are using caused it, or if you want to record your
4711 system state for reproducibility purposes. The @command{guix describe}
4712 command answers these questions.
4714 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4715 displays the channel(s) that it was built from, including their repository URL
4716 and commit IDs (@pxref{Channels}):
4720 Generation 10 Sep 03 2018 17:32:44 (current)
4722 repository URL: https://git.savannah.gnu.org/git/guix.git
4724 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4727 If you're familiar with the Git version control system, this is similar in
4728 spirit to @command{git describe}; the output is also similar to that of
4729 @command{guix pull --list-generations}, but limited to the current generation
4730 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4731 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4732 information is all it takes to describe the revision of Guix you're using, and
4733 also to replicate it.
4735 To make it easier to replicate Guix, @command{guix describe} can also be asked
4736 to return a list of channels instead of the human-readable description above:
4739 $ guix describe -f channels
4742 (url "https://git.savannah.gnu.org/git/guix.git")
4744 "e0fa68c7718fffd33d81af415279d6ddb518f727")
4746 (make-channel-introduction
4747 "9edb3f66fd807b096b48283debdcddccfea34bad"
4748 (openpgp-fingerprint
4749 "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
4753 You can save this to a file and feed it to @command{guix pull -C} on some
4754 other machine or at a later point in time, which will instantiate @emph{this
4755 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4756 From there on, since you're able to deploy the same revision of Guix, you can
4757 just as well @emph{replicate a complete software environment}. We humbly
4758 think that this is @emph{awesome}, and we hope you'll like it too!
4760 The details of the options supported by @command{guix describe} are as
4764 @item --format=@var{format}
4765 @itemx -f @var{format}
4766 Produce output in the specified @var{format}, one of:
4770 produce human-readable output;
4772 produce a list of channel specifications that can be passed to @command{guix
4773 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4775 @item channels-sans-intro
4776 like @code{channels}, but omit the @code{introduction} field; use it to
4777 produce a channel specification suitable for Guix version 1.1.0 or
4778 earlier---the @code{introduction} field has to do with channel
4779 authentication (@pxref{Channels, Channel Authentication}) and is not
4780 supported by these older versions;
4783 produce a list of channel specifications in JSON format;
4785 produce a list of channel specifications in Recutils format.
4788 @item --list-formats
4789 Display available formats for @option{--format} option.
4791 @item --profile=@var{profile}
4792 @itemx -p @var{profile}
4793 Display information about @var{profile}.
4796 @node Invoking guix archive
4797 @section Invoking @command{guix archive}
4799 @cindex @command{guix archive}
4801 The @command{guix archive} command allows users to @dfn{export} files
4802 from the store into a single archive, and to later @dfn{import} them on
4803 a machine that runs Guix.
4804 In particular, it allows store files to be transferred from one machine
4805 to the store on another machine.
4808 If you're looking for a way to produce archives in a format suitable for
4809 tools other than Guix, @pxref{Invoking guix pack}.
4812 @cindex exporting store items
4813 To export store files as an archive to standard output, run:
4816 guix archive --export @var{options} @var{specifications}...
4819 @var{specifications} may be either store file names or package
4820 specifications, as for @command{guix package} (@pxref{Invoking guix
4821 package}). For instance, the following command creates an archive
4822 containing the @code{gui} output of the @code{git} package and the main
4823 output of @code{emacs}:
4826 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4829 If the specified packages are not built yet, @command{guix archive}
4830 automatically builds them. The build process may be controlled with the
4831 common build options (@pxref{Common Build Options}).
4833 To transfer the @code{emacs} package to a machine connected over SSH,
4837 guix archive --export -r emacs | ssh the-machine guix archive --import
4841 Similarly, a complete user profile may be transferred from one machine
4842 to another like this:
4845 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4846 ssh the-machine guix archive --import
4850 However, note that, in both examples, all of @code{emacs} and the
4851 profile as well as all of their dependencies are transferred (due to
4852 @option{-r}), regardless of what is already available in the store on
4853 the target machine. The @option{--missing} option can help figure out
4854 which items are missing from the target store. The @command{guix copy}
4855 command simplifies and optimizes this whole process, so this is probably
4856 what you should use in this case (@pxref{Invoking guix copy}).
4858 @cindex nar, archive format
4859 @cindex normalized archive (nar)
4860 @cindex nar bundle, archive format
4861 Each store item is written in the @dfn{normalized archive} or @dfn{nar}
4862 format (described below), and the output of @command{guix archive
4863 --export} (and input of @command{guix archive --import}) is a @dfn{nar
4867 comparable in spirit to `tar', but with differences
4868 that make it more appropriate for our purposes. First, rather than
4869 recording all Unix metadata for each file, the nar format only mentions
4870 the file type (regular, directory, or symbolic link); Unix permissions
4871 and owner/group are dismissed. Second, the order in which directory
4872 entries are stored always follows the order of file names according to
4873 the C locale collation order. This makes archive production fully
4876 That nar bundle format is essentially the concatenation of zero or more
4877 nars along with metadata for each store item it contains: its file name,
4878 references, corresponding derivation, and a digital signature.
4880 When exporting, the daemon digitally signs the contents of the archive,
4881 and that digital signature is appended. When importing, the daemon
4882 verifies the signature and rejects the import in case of an invalid
4883 signature or if the signing key is not authorized.
4884 @c FIXME: Add xref to daemon doc about signatures.
4886 The main options are:
4890 Export the specified store files or packages (see below). Write the
4891 resulting archive to the standard output.
4893 Dependencies are @emph{not} included in the output, unless
4894 @option{--recursive} is passed.
4898 When combined with @option{--export}, this instructs @command{guix archive}
4899 to include dependencies of the given items in the archive. Thus, the
4900 resulting archive is self-contained: it contains the closure of the
4901 exported store items.
4904 Read an archive from the standard input, and import the files listed
4905 therein into the store. Abort if the archive has an invalid digital
4906 signature, or if it is signed by a public key not among the authorized
4907 keys (see @option{--authorize} below).
4910 Read a list of store file names from the standard input, one per line,
4911 and write on the standard output the subset of these files missing from
4914 @item --generate-key[=@var{parameters}]
4915 @cindex signing, archives
4916 Generate a new key pair for the daemon. This is a prerequisite before
4917 archives can be exported with @option{--export}. This
4918 operation is usually instantaneous but it can take time if the system's
4919 entropy pool needs to be refilled. On Guix System,
4920 @code{guix-service-type} takes care of generating this key pair the
4923 The generated key pair is typically stored under @file{/etc/guix}, in
4924 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4925 key, which must be kept secret). When @var{parameters} is omitted,
4926 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4927 versions before 1.6.0, it is a 4096-bit RSA key.
4928 Alternatively, @var{parameters} can specify
4929 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4930 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4931 Libgcrypt Reference Manual}).
4934 @cindex authorizing, archives
4935 Authorize imports signed by the public key passed on standard input.
4936 The public key must be in ``s-expression advanced format''---i.e., the
4937 same format as the @file{signing-key.pub} file.
4939 The list of authorized keys is kept in the human-editable file
4940 @file{/etc/guix/acl}. The file contains
4941 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4942 s-expressions''} and is structured as an access-control list in the
4943 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4946 @item --extract=@var{directory}
4947 @itemx -x @var{directory}
4948 Read a single-item archive as served by substitute servers
4949 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4950 low-level operation needed in only very narrow use cases; see below.
4952 For example, the following command extracts the substitute for Emacs
4953 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4957 https://@value{SUBSTITUTE-SERVER}/nar/gzip/@dots{}-emacs-24.5 \
4958 | gunzip | guix archive -x /tmp/emacs
4961 Single-item archives are different from multiple-item archives produced
4962 by @command{guix archive --export}; they contain a single store item,
4963 and they do @emph{not} embed a signature. Thus this operation does
4964 @emph{no} signature verification and its output should be considered
4967 The primary purpose of this operation is to facilitate inspection of
4968 archive contents coming from possibly untrusted substitute servers
4969 (@pxref{Invoking guix challenge}).
4973 Read a single-item archive as served by substitute servers
4974 (@pxref{Substitutes}) and print the list of files it contains, as in
4979 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4980 | lzip -d | guix archive -t
4985 @c *********************************************************************
4990 @cindex @file{channels.scm}, configuration file
4991 @cindex configuration file for channels
4992 @cindex @command{guix pull}, configuration file
4993 @cindex configuration of @command{guix pull}
4994 Guix and its package collection are updated by running @command{guix pull}
4995 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
4996 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
4997 customized by defining @dfn{channels} in the
4998 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
4999 of a Git repository to be deployed, and @command{guix pull} can be instructed
5000 to pull from one or more channels. In other words, channels can be used
5001 to @emph{customize} and to @emph{extend} Guix, as we will see below.
5002 Guix is able to take into account security concerns and deal with authenticated
5006 * Specifying Additional Channels:: Extending the package collection.
5007 * Using a Custom Guix Channel:: Using a customized Guix.
5008 * Replicating Guix:: Running the @emph{exact same} Guix.
5009 * Channel Authentication:: How Guix verifies what it fetches.
5010 * Creating a Channel:: How to write your custom channel.
5011 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
5012 * Declaring Channel Dependencies:: How to depend on other channels.
5013 * Specifying Channel Authorizations:: Defining channel authors authorizations.
5014 * Primary URL:: Distinguishing mirror to original.
5015 * Writing Channel News:: Communicating information to channel's users.
5016 * Channels with Substitutes:: Using channels with available substitutes.
5019 @node Specifying Additional Channels
5020 @section Specifying Additional Channels
5022 @cindex extending the package collection (channels)
5023 @cindex variant packages (channels)
5024 You can specify @emph{additional channels} to pull from. To use a channel, write
5025 @code{~/.config/guix/channels.scm} to instruct @command{guix pull} to pull from it
5026 @emph{in addition} to the default Guix channel(s):
5028 @vindex %default-channels
5030 ;; Add variant packages to those Guix provides.
5032 (name 'variant-packages)
5033 (url "https://example.org/variant-packages.git"))
5038 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
5039 add a channel the list of channels that the variable @code{%default-channels}
5040 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
5041 Manual}). With this file in place, @command{guix pull} builds not only Guix
5042 but also the package modules from your own repository. The result in
5043 @file{~/.config/guix/current} is the union of Guix with your own package
5047 $ guix pull --list-generations
5049 Generation 19 Aug 27 2018 16:20:48
5051 repository URL: https://git.savannah.gnu.org/git/guix.git
5053 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
5054 variant-packages dd3df5e
5055 repository URL: https://example.org/variant-packages.git
5057 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
5058 11 new packages: variant-gimp, variant-emacs-with-cool-features, @dots{}
5059 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
5063 The output of @command{guix pull} above shows that Generation@tie{}19 includes
5064 both Guix and packages from the @code{variant-personal-packages} channel. Among
5065 the new and upgraded packages that are listed, some like @code{variant-gimp} and
5066 @code{variant-emacs-with-cool-features} might come from
5067 @code{variant-packages}, while others come from the Guix default channel.
5069 @node Using a Custom Guix Channel
5070 @section Using a Custom Guix Channel
5072 The channel called @code{guix} specifies where Guix itself---its command-line
5073 tools as well as its package collection---should be downloaded. For instance,
5074 suppose you want to update from another copy of the Guix repository at
5075 @code{example.org}, and specifically the @code{super-hacks} branch, you can
5076 write in @code{~/.config/guix/channels.scm} this specification:
5079 ;; Tell 'guix pull' to use another repo.
5082 (url "https://example.org/another-guix.git")
5083 (branch "super-hacks")))
5087 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
5088 branch of the repository at @code{example.org}. The authentication concern is
5089 addressed below ((@pxref{Channel Authentication}).
5091 @node Replicating Guix
5092 @section Replicating Guix
5094 @cindex pinning, channels
5095 @cindex replicating Guix
5096 @cindex reproducibility, of Guix
5097 The @command{guix pull --list-generations} output above shows precisely which
5098 commits were used to build this instance of Guix. We can thus replicate it,
5099 say, on another machine, by providing a channel specification in
5100 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
5103 ;; Deploy specific commits of my channels of interest.
5106 (url "https://git.savannah.gnu.org/git/guix.git")
5107 (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
5109 (name 'variant-packages)
5110 (url "https://example.org/variant-packages.git")
5111 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
5114 The @command{guix describe --format=channels} command can even generate this
5115 list of channels directly (@pxref{Invoking guix describe}). The resulting
5116 file can be used with the -C options of @command{guix pull}
5117 (@pxref{Invoking guix pull}) or @command{guix time-machine}
5118 (@pxref{Invoking guix time-machine}).
5120 At this point the two machines run the @emph{exact same Guix}, with access to
5121 the @emph{exact same packages}. The output of @command{guix build gimp} on
5122 one machine will be exactly the same, bit for bit, as the output of the same
5123 command on the other machine. It also means both machines have access to all
5124 the source code of Guix and, transitively, to all the source code of every
5127 This gives you super powers, allowing you to track the provenance of binary
5128 artifacts with very fine grain, and to reproduce software environments at
5129 will---some sort of ``meta reproducibility'' capabilities, if you will.
5130 @xref{Inferiors}, for another way to take advantage of these super powers.
5132 @node Channel Authentication
5133 @section Channel Authentication
5135 @anchor{channel-authentication}
5136 @cindex authentication, of channel code
5137 The @command{guix pull} and @command{guix time-machine} commands
5138 @dfn{authenticate} the code retrieved from channels: they make sure each
5139 commit that is fetched is signed by an authorized developer. The goal
5140 is to protect from unauthorized modifications to the channel that would
5141 lead users to run malicious code.
5143 As a user, you must provide a @dfn{channel introduction} in your
5144 channels file so that Guix knows how to authenticate its first commit.
5145 A channel specification, including its introduction, looks something
5150 (name 'some-channel)
5151 (url "https://example.org/some-channel.git")
5153 (make-channel-introduction
5154 "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
5155 (openpgp-fingerprint
5156 "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5159 The specification above shows the name and URL of the channel. The call
5160 to @code{make-channel-introduction} above specifies that authentication
5161 of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
5162 by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
5164 For the main channel, called @code{guix}, you automatically get that
5165 information from your Guix installation. For other channels, include
5166 the channel introduction provided by the channel authors in your
5167 @file{channels.scm} file. Make sure you retrieve the channel
5168 introduction from a trusted source since that is the root of your trust.
5170 If you're curious about the authentication mechanics, read on!
5172 @node Creating a Channel
5173 @section Creating a Channel
5175 @cindex personal packages (channels)
5176 @cindex channels, for personal packages
5177 Let's say you have a bunch of custom package variants or personal packages
5178 that you think would make little sense to contribute to the Guix project, but
5179 would like to have these packages transparently available to you at the
5180 command line. You would first write modules containing those package
5181 definitions (@pxref{Package Modules}), maintain them in a Git repository, and
5182 then you and anyone else can use it as an additional channel to get packages
5185 @c What follows stems from discussions at
5186 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
5187 @c earlier discussions on guix-devel@gnu.org.
5189 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
5190 publish your personal channel to the world, we would like to share a few words
5195 Before publishing a channel, please consider contributing your package
5196 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
5197 to free software of all sorts, and packages in Guix proper are readily
5198 available to all Guix users and benefit from the project's quality assurance
5202 When you maintain package definitions outside Guix, we, Guix developers,
5203 consider that @emph{the compatibility burden is on you}. Remember that
5204 package modules and package definitions are just Scheme code that uses various
5205 programming interfaces (APIs). We want to remain free to change these APIs to
5206 keep improving Guix, possibly in ways that break your channel. We never
5207 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
5211 Corollary: if you're using an external channel and that channel breaks, please
5212 @emph{report the issue to the channel authors}, not to the Guix project.
5215 You've been warned! Having said this, we believe external channels are a
5216 practical way to exert your freedom to augment Guix' package collection and to
5217 share your improvements, which are basic tenets of
5218 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
5219 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
5222 To create a channel, create a Git repository containing your own package
5223 modules and make it available. The repository can contain anything, but a
5224 useful channel will contain Guile modules that export packages. Once you
5225 start using a channel, Guix will behave as if the root directory of that
5226 channel's Git repository has been added to the Guile load path (@pxref{Load
5227 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
5228 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
5229 module, then the module will be available under the name @code{(my-packages
5230 my-tools)}, and you will be able to use it like any other module
5231 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
5233 As a channel author, consider bundling authentication material with your
5234 channel so that users can authenticate it. @xref{Channel
5235 Authentication}, and @ref{Specifying Channel Authorizations}, for info
5239 @node Package Modules in a Sub-directory
5240 @section Package Modules in a Sub-directory
5242 @cindex subdirectory, channels
5243 As a channel author, you may want to keep your channel modules in a
5244 sub-directory. If your modules are in the sub-directory @file{guix}, you must
5245 add a meta-data file @file{.guix-channel} that contains:
5253 @node Declaring Channel Dependencies
5254 @section Declaring Channel Dependencies
5256 @cindex dependencies, channels
5257 @cindex meta-data, channels
5258 Channel authors may decide to augment a package collection provided by other
5259 channels. They can declare their channel to be dependent on other channels in
5260 a meta-data file @file{.guix-channel}, which is to be placed in the root of
5261 the channel repository.
5263 The meta-data file should contain a simple S-expression like this:
5270 (name 'some-collection)
5271 (url "https://example.org/first-collection.git")
5273 ;; The 'introduction' bit below is optional: you would
5274 ;; provide it for dependencies that can be authenticated.
5276 (channel-introduction
5278 (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
5279 (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5281 (name 'some-other-collection)
5282 (url "https://example.org/second-collection.git")
5283 (branch "testing"))))
5286 In the above example this channel is declared to depend on two other channels,
5287 which will both be fetched automatically. The modules provided by the channel
5288 will be compiled in an environment where the modules of all these declared
5289 channels are available.
5291 For the sake of reliability and maintainability, you should avoid dependencies
5292 on channels that you don't control, and you should aim to keep the number of
5293 dependencies to a minimum.
5295 @node Specifying Channel Authorizations
5296 @section Specifying Channel Authorizations
5298 @cindex channel authorizations
5299 @anchor{channel-authorizations}
5300 As we saw above, Guix ensures the source code it pulls from channels
5301 comes from authorized developers. As a channel author, you need to
5302 specify the list of authorized developers in the
5303 @file{.guix-authorizations} file in the channel's Git repository. The
5304 authentication rule is simple: each commit must be signed by a key
5305 listed in the @file{.guix-authorizations} file of its parent
5306 commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
5307 (DAG). Each commit can have zero or more parents; ``regular'' commits
5308 have one parent and merge commits have two parent commits. Read
5309 @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
5310 for Computer Scientists}} for a great overview.} The
5311 @file{.guix-authorizations} file looks like this:
5314 ;; Example '.guix-authorizations' file.
5317 (version 0) ;current file format version
5319 (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
5321 ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
5323 ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
5327 Each fingerprint is followed by optional key/value pairs, as in the
5328 example above. Currently these key/value pairs are ignored.
5330 This authentication rule creates a chicken-and-egg issue: how do we
5331 authenticate the first commit? Related to that: how do we deal with
5332 channels whose repository history contains unsigned commits and lack
5333 @file{.guix-authorizations}? And how do we fork existing channels?
5335 @cindex channel introduction
5336 Channel introductions answer these questions by describing the first
5337 commit of a channel that should be authenticated. The first time a
5338 channel is fetched with @command{guix pull} or @command{guix
5339 time-machine}, the command looks up the introductory commit and verifies
5340 that it is signed by the specified OpenPGP key. From then on, it
5341 authenticates commits according to the rule above.
5343 Additionally, your channel must provide all the OpenPGP keys that were
5344 ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
5345 files, which can be either binary or ``ASCII-armored''. By default,
5346 those @file{.key} files are searched for in the branch named
5347 @code{keyring} but you can specify a different branch name in
5348 @code{.guix-channel} like so:
5353 (keyring-reference "my-keyring-branch"))
5356 To summarize, as the author of a channel, there are three things you have
5357 to do to allow users to authenticate your code:
5361 Export the OpenPGP keys of past and present committers with @command{gpg
5362 --export} and store them in @file{.key} files, by default in a branch
5363 named @code{keyring} (we recommend making it an @dfn{orphan branch}).
5366 Introduce an initial @file{.guix-authorizations} in the channel's
5367 repository. Do that in a signed commit (@pxref{Commit Access}, for
5368 information on how to sign Git commits.)
5371 Advertise the channel introduction, for instance on your channel's web
5372 page. The channel introduction, as we saw above, is the commit/key
5373 pair---i.e., the commit that introduced @file{.guix-authorizations}, and
5374 the fingerprint of the OpenPGP used to sign it.
5377 Before pushing to your public Git repository, you can run @command{guix
5378 git-authenticate} to verify that you did sign all the commits you are
5379 about to push with an authorized key:
5382 guix git authenticate @var{commit} @var{signer}
5386 where @var{commit} and @var{signer} are your channel introduction.
5387 @xref{Invoking guix git authenticate}, for details.
5389 Publishing a signed channel requires discipline: any mistake, such as an
5390 unsigned commit or a commit signed by an unauthorized key, will prevent
5391 users from pulling from your channel---well, that's the whole point of
5392 authentication! Pay attention to merges in particular: merge commits
5393 are considered authentic if and only if they are signed by a key present
5394 in the @file{.guix-authorizations} file of @emph{both} branches.
5397 @section Primary URL
5399 @cindex primary URL, channels
5400 Channel authors can indicate the primary URL of their channel's Git
5401 repository in the @file{.guix-channel} file, like so:
5406 (url "https://example.org/guix.git"))
5409 This allows @command{guix pull} to determine whether it is pulling code
5410 from a mirror of the channel; when that is the case, it warns the user
5411 that the mirror might be stale and displays the primary URL@. That way,
5412 users cannot be tricked into fetching code from a stale mirror that does
5413 not receive security updates.
5415 This feature only makes sense for authenticated repositories, such as
5416 the official @code{guix} channel, for which @command{guix pull} ensures
5417 the code it fetches is authentic.
5419 @node Writing Channel News
5420 @section Writing Channel News
5422 @cindex news, for channels
5423 Channel authors may occasionally want to communicate to their users
5424 information about important changes in the channel. You'd send them all
5425 an email, but that's not convenient.
5427 Instead, channels can provide a @dfn{news file}; when the channel users
5428 run @command{guix pull}, that news file is automatically read and
5429 @command{guix pull --news} can display the announcements that correspond
5430 to the new commits that have been pulled, if any.
5432 To do that, channel authors must first declare the name of the news file
5433 in their @file{.guix-channel} file:
5438 (news-file "etc/news.txt"))
5441 The news file itself, @file{etc/news.txt} in this example, must look
5442 something like this:
5447 (entry (tag "the-bug-fix")
5448 (title (en "Fixed terrible bug")
5450 (body (en "@@emph@{Good news@}! It's fixed!")
5451 (eo "Certe ĝi pli bone funkcias nun!")))
5452 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
5453 (title (en "Added a great package")
5454 (ca "Què vol dir guix?"))
5455 (body (en "Don't miss the @@code@{hello@} package!"))))
5458 While the news file is using the Scheme syntax, avoid naming it with a
5459 @file{.scm} extension or else it will get picked up when building the
5460 channel and yield an error since it is not a valid module.
5461 Alternatively, you can move the channel module to a subdirectory and
5462 store the news file in another directory.
5464 The file consists of a list of @dfn{news entries}. Each entry is
5465 associated with a commit or tag: it describes changes made in this
5466 commit, possibly in preceding commits as well. Users see entries only
5467 the first time they obtain the commit the entry refers to.
5469 The @code{title} field should be a one-line summary while @code{body}
5470 can be arbitrarily long, and both can contain Texinfo markup
5471 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
5472 a list of language tag/message tuples, which allows @command{guix pull}
5473 to display news in the language that corresponds to the user's locale.
5475 If you want to translate news using a gettext-based workflow, you can
5476 extract translatable strings with @command{xgettext} (@pxref{xgettext
5477 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
5478 you write news entries in English first, the command below creates a PO
5479 file containing the strings to translate:
5482 xgettext -o news.po -l scheme -ken etc/news.txt
5485 To sum up, yes, you could use your channel as a blog. But beware, this
5486 is @emph{not quite} what your users might expect.
5488 @node Channels with Substitutes
5489 @section Channels with Substitutes
5491 When running @command{guix pull}, Guix will first compile the
5492 definitions of every available package. This is an expensive operation
5493 for which substitutes (@pxref{Substitutes}) may be available. The
5494 following snippet in @file{channels.scm} will ensure that @command{guix
5495 pull} uses the latest commit with available substitutes for the package
5496 definitions: this is done by querying the continuous integration
5497 server at @url{https://ci.guix.gnu.org}.
5500 (use-modules (guix ci))
5502 (list (channel-with-substitutes-available
5503 %default-guix-channel
5504 "https://ci.guix.gnu.org"))
5507 Note that this does not mean that all the packages that you will
5508 install after running @command{guix pull} will have available
5509 substitutes. It only ensures that @command{guix pull} will not try to
5510 compile package definitions. This is particularly useful when using
5511 machines with limited resources.
5513 @c *********************************************************************
5515 @chapter Development
5517 @cindex software development
5518 If you are a software developer, Guix provides tools that you should find
5519 helpful---independently of the language you're developing in. This is what
5520 this chapter is about.
5522 The @command{guix environment} command provides a convenient way to set up
5523 @dfn{development environments} containing all the dependencies and tools
5524 necessary to work on the software package of your choice. The @command{guix
5525 pack} command allows you to create @dfn{application bundles} that can be
5526 easily distributed to users who do not run Guix.
5529 * Invoking guix environment:: Setting up development environments.
5530 * Invoking guix pack:: Creating software bundles.
5531 * The GCC toolchain:: Working with languages supported by GCC.
5532 * Invoking guix git authenticate:: Authenticating Git repositories.
5535 @node Invoking guix environment
5536 @section Invoking @command{guix environment}
5538 @cindex reproducible build environments
5539 @cindex development environments
5540 @cindex @command{guix environment}
5541 @cindex environment, package build environment
5542 The purpose of @command{guix environment} is to assist hackers in
5543 creating reproducible development environments without polluting their
5544 package profile. The @command{guix environment} tool takes one or more
5545 packages, builds all of their inputs, and creates a shell
5546 environment to use them.
5548 The general syntax is:
5551 guix environment @var{options} @var{package}@dots{}
5554 The following example spawns a new shell set up for the development of
5558 guix environment guile
5561 If the needed dependencies are not built yet, @command{guix environment}
5562 automatically builds them. The environment of the new shell is an
5563 augmented version of the environment that @command{guix environment} was
5564 run in. It contains the necessary search paths for building the given
5565 package added to the existing environment variables. To create
5566 a ``pure'' environment, in which the original environment variables have
5567 been unset, use the @option{--pure} option@footnote{Users sometimes
5568 wrongfully augment environment variables such as @env{PATH} in their
5569 @file{~/.bashrc} file. As a consequence, when @command{guix
5570 environment} launches it, Bash may read @file{~/.bashrc}, thereby
5571 introducing ``impurities'' in these environment variables. It is an
5572 error to define such environment variables in @file{.bashrc}; instead,
5573 they should be defined in @file{.bash_profile}, which is sourced only by
5574 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
5575 Manual}, for details on Bash start-up files.}.
5577 Exiting from a Guix environment is the same as exiting from the shell,
5578 and will place the user back in the old environment before @command{guix
5579 environment} was invoked. The next garbage collection (@pxref{Invoking
5580 guix gc}) will clean up packages that were installed from within the
5581 environment and are no longer used outside of it.
5583 @vindex GUIX_ENVIRONMENT
5584 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
5585 variable in the shell it spawns; its value is the file name of the
5586 profile of this environment. This allows users to, say, define a
5587 specific prompt for development environments in their @file{.bashrc}
5588 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
5591 if [ -n "$GUIX_ENVIRONMENT" ]
5593 export PS1="\u@@\h \w [dev]\$ "
5598 ...@: or to browse the profile:
5601 $ ls "$GUIX_ENVIRONMENT/bin"
5604 Additionally, more than one package may be specified, in which case the
5605 union of the inputs for the given packages are used. For example, the
5606 command below spawns a shell where all of the dependencies of both Guile
5607 and Emacs are available:
5610 guix environment guile emacs
5613 Sometimes an interactive shell session is not desired. An arbitrary
5614 command may be invoked by placing the @code{--} token to separate the
5615 command from the rest of the arguments:
5618 guix environment guile -- make -j4
5621 In other situations, it is more convenient to specify the list of
5622 packages needed in the environment. For example, the following command
5623 runs @command{python} from an environment containing Python@tie{}2.7 and
5627 guix environment --ad-hoc python2-numpy python-2.7 -- python
5630 Furthermore, one might want the dependencies of a package and also some
5631 additional packages that are not build-time or runtime dependencies, but
5632 are useful when developing nonetheless. Because of this, the
5633 @option{--ad-hoc} flag is positional. Packages appearing before
5634 @option{--ad-hoc} are interpreted as packages whose dependencies will be
5635 added to the environment. Packages appearing after are interpreted as
5636 packages that will be added to the environment directly. For example,
5637 the following command creates a Guix development environment that
5638 additionally includes Git and strace:
5641 guix environment --pure guix --ad-hoc git strace
5645 Sometimes it is desirable to isolate the environment as much as
5646 possible, for maximal purity and reproducibility. In particular, when
5647 using Guix on a host distro that is not Guix System, it is desirable to
5648 prevent access to @file{/usr/bin} and other system-wide resources from
5649 the development environment. For example, the following command spawns
5650 a Guile REPL in a ``container'' where only the store and the current
5651 working directory are mounted:
5654 guix environment --ad-hoc --container guile -- guile
5658 The @option{--container} option requires Linux-libre 3.19 or newer.
5661 @cindex certificates
5662 Another typical use case for containers is to run security-sensitive
5663 applications such as a web browser. To run Eolie, we must expose and
5664 share some files and directories; we include @code{nss-certs} and expose
5665 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
5666 @env{DISPLAY} environment variable since containerized graphical
5667 applications won't display without it.
5670 guix environment --preserve='^DISPLAY$' --container --network \
5671 --expose=/etc/machine-id \
5672 --expose=/etc/ssl/certs/ \
5673 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
5674 --ad-hoc eolie nss-certs dbus -- eolie
5677 The available options are summarized below.
5680 @item --root=@var{file}
5681 @itemx -r @var{file}
5682 @cindex persistent environment
5683 @cindex garbage collector root, for environments
5684 Make @var{file} a symlink to the profile for this environment, and
5685 register it as a garbage collector root.
5687 This is useful if you want to protect your environment from garbage
5688 collection, to make it ``persistent''.
5690 When this option is omitted, the environment is protected from garbage
5691 collection only for the duration of the @command{guix environment}
5692 session. This means that next time you recreate the same environment,
5693 you could have to rebuild or re-download packages. @xref{Invoking guix
5694 gc}, for more on GC roots.
5696 @item --expression=@var{expr}
5697 @itemx -e @var{expr}
5698 Create an environment for the package or list of packages that
5699 @var{expr} evaluates to.
5701 For example, running:
5704 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
5707 starts a shell with the environment for this specific variant of the
5713 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
5716 starts a shell with all the base system packages available.
5718 The above commands only use the default output of the given packages.
5719 To select other outputs, two element tuples can be specified:
5722 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
5725 @item --load=@var{file}
5726 @itemx -l @var{file}
5727 Create an environment for the package or list of packages that the code
5728 within @var{file} evaluates to.
5730 As an example, @var{file} might contain a definition like this
5731 (@pxref{Defining Packages}):
5734 @verbatiminclude environment-gdb.scm
5737 @item --manifest=@var{file}
5738 @itemx -m @var{file}
5739 Create an environment for the packages contained in the manifest object
5740 returned by the Scheme code in @var{file}. This option can be repeated
5741 several times, in which case the manifests are concatenated.
5743 This is similar to the same-named option in @command{guix package}
5744 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
5748 Include all specified packages in the resulting environment, as if an
5749 @i{ad hoc} package were defined with them as inputs. This option is
5750 useful for quickly creating an environment without having to write a
5751 package expression to contain the desired inputs.
5753 For instance, the command:
5756 guix environment --ad-hoc guile guile-sdl -- guile
5759 runs @command{guile} in an environment where Guile and Guile-SDL are
5762 Note that this example implicitly asks for the default output of
5763 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
5764 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
5765 of @code{glib} (@pxref{Packages with Multiple Outputs}).
5767 This option may be composed with the default behavior of @command{guix
5768 environment}. Packages appearing before @option{--ad-hoc} are
5769 interpreted as packages whose dependencies will be added to the
5770 environment, the default behavior. Packages appearing after are
5771 interpreted as packages that will be added to the environment directly.
5774 Unset existing environment variables when building the new environment, except
5775 those specified with @option{--preserve} (see below). This has the effect of
5776 creating an environment in which search paths only contain package inputs.
5778 @item --preserve=@var{regexp}
5779 @itemx -E @var{regexp}
5780 When used alongside @option{--pure}, preserve the environment variables
5781 matching @var{regexp}---in other words, put them on a ``white list'' of
5782 environment variables that must be preserved. This option can be repeated
5786 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
5790 This example runs @command{mpirun} in a context where the only environment
5791 variables defined are @env{PATH}, environment variables whose name starts
5792 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
5795 @item --search-paths
5796 Display the environment variable definitions that make up the
5799 @item --system=@var{system}
5800 @itemx -s @var{system}
5801 Attempt to build for @var{system}---e.g., @code{i686-linux}.
5806 Run @var{command} within an isolated container. The current working
5807 directory outside the container is mapped inside the container.
5808 Additionally, unless overridden with @option{--user}, a dummy home
5809 directory is created that matches the current user's home directory, and
5810 @file{/etc/passwd} is configured accordingly.
5812 The spawned process runs as the current user outside the container. Inside
5813 the container, it has the same UID and GID as the current user, unless
5814 @option{--user} is passed (see below).
5818 For containers, share the network namespace with the host system.
5819 Containers created without this flag only have access to the loopback
5822 @item --link-profile
5824 For containers, link the environment profile to @file{~/.guix-profile}
5825 within the container and set @code{GUIX_ENVIRONMENT} to that.
5826 This is equivalent to making @file{~/.guix-profile} a symlink to the
5827 actual profile within the container.
5828 Linking will fail and abort the environment if the directory already
5829 exists, which will certainly be the case if @command{guix environment}
5830 was invoked in the user's home directory.
5832 Certain packages are configured to look in @file{~/.guix-profile} for
5833 configuration files and data;@footnote{For example, the
5834 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
5835 for additional fonts.} @option{--link-profile} allows these programs to
5836 behave as expected within the environment.
5838 @item --user=@var{user}
5839 @itemx -u @var{user}
5840 For containers, use the username @var{user} in place of the current
5841 user. The generated @file{/etc/passwd} entry within the container will
5842 contain the name @var{user}, the home directory will be
5843 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
5844 the UID and GID inside the container are 1000. @var{user}
5845 need not exist on the system.
5847 Additionally, any shared or exposed path (see @option{--share} and
5848 @option{--expose} respectively) whose target is within the current user's
5849 home directory will be remapped relative to @file{/home/USER}; this
5850 includes the automatic mapping of the current working directory.
5853 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
5855 guix environment --container --user=foo \
5856 --expose=$HOME/test \
5857 --expose=/tmp/target=$HOME/target
5860 While this will limit the leaking of user identity through home paths
5861 and each of the user fields, this is only one useful component of a
5862 broader privacy/anonymity solution---not one in and of itself.
5865 For containers, the default behavior is to share the current working
5866 directory with the isolated container and immediately change to that
5867 directory within the container. If this is undesirable,
5868 @option{--no-cwd} will cause the current working directory to @emph{not}
5869 be automatically shared and will change to the user's home directory
5870 within the container instead. See also @option{--user}.
5872 @item --expose=@var{source}[=@var{target}]
5873 @itemx --share=@var{source}[=@var{target}]
5874 For containers, @option{--expose} (resp. @option{--share}) exposes the
5875 file system @var{source} from the host system as the read-only
5876 (resp. writable) file system @var{target} within the container. If
5877 @var{target} is not specified, @var{source} is used as the target mount
5878 point in the container.
5880 The example below spawns a Guile REPL in a container in which the user's
5881 home directory is accessible read-only via the @file{/exchange}
5885 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
5890 @command{guix environment}
5891 also supports all of the common build options that @command{guix
5892 build} supports (@pxref{Common Build Options}) as well as package
5893 transformation options (@pxref{Package Transformation Options}).
5895 @node Invoking guix pack
5896 @section Invoking @command{guix pack}
5898 Occasionally you want to pass software to people who are not (yet!)
5899 lucky enough to be using Guix. You'd tell them to run @command{guix
5900 package -i @var{something}}, but that's not possible in this case. This
5901 is where @command{guix pack} comes in.
5904 If you are looking for ways to exchange binaries among machines that
5905 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5906 publish}, and @ref{Invoking guix archive}.
5911 @cindex application bundle
5912 @cindex software bundle
5913 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5914 @dfn{software bundle}: it creates a tarball or some other archive
5915 containing the binaries of the software you're interested in, and all
5916 its dependencies. The resulting archive can be used on any machine that
5917 does not have Guix, and people can run the exact same binaries as those
5918 you have with Guix. The pack itself is created in a bit-reproducible
5919 fashion, so anyone can verify that it really contains the build results
5920 that you pretend to be shipping.
5922 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5923 their dependencies, you can run:
5926 $ guix pack guile emacs geiser
5928 /gnu/store/@dots{}-pack.tar.gz
5931 The result here is a tarball containing a @file{/gnu/store} directory
5932 with all the relevant packages. The resulting tarball contains a
5933 @dfn{profile} with the three packages of interest; the profile is the
5934 same as would be created by @command{guix package -i}. It is this
5935 mechanism that is used to create Guix's own standalone binary tarball
5936 (@pxref{Binary Installation}).
5938 Users of this pack would have to run
5939 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5940 find inconvenient. To work around it, you can create, say, a
5941 @file{/opt/gnu/bin} symlink to the profile:
5944 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5948 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5950 @cindex relocatable binaries, with @command{guix pack}
5951 What if the recipient of your pack does not have root privileges on
5952 their machine, and thus cannot unpack it in the root file system? In
5953 that case, you will want to use the @option{--relocatable} option (see
5954 below). This option produces @dfn{relocatable binaries}, meaning they
5955 they can be placed anywhere in the file system hierarchy: in the example
5956 above, users can unpack your tarball in their home directory and
5957 directly run @file{./opt/gnu/bin/guile}.
5959 @cindex Docker, build an image with guix pack
5960 Alternatively, you can produce a pack in the Docker image format using
5961 the following command:
5964 guix pack -f docker -S /bin=bin guile guile-readline
5968 The result is a tarball that can be passed to the @command{docker load}
5969 command, followed by @code{docker run}:
5972 docker load < @var{file}
5973 docker run -ti guile-guile-readline /bin/guile
5977 where @var{file} is the image returned by @var{guix pack}, and
5978 @code{guile-guile-readline} is its ``image tag''. See the
5979 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5980 documentation} for more information.
5982 @cindex Singularity, build an image with guix pack
5983 @cindex SquashFS, build an image with guix pack
5984 Yet another option is to produce a SquashFS image with the following
5988 guix pack -f squashfs bash guile emacs geiser
5992 The result is a SquashFS file system image that can either be mounted or
5993 directly be used as a file system container image with the
5994 @uref{https://www.sylabs.io/docs/, Singularity container execution
5995 environment}, using commands like @command{singularity shell} or
5996 @command{singularity exec}.
5998 Several command-line options allow you to customize your pack:
6001 @item --format=@var{format}
6002 @itemx -f @var{format}
6003 Produce a pack in the given @var{format}.
6005 The available formats are:
6009 This is the default format. It produces a tarball containing all the
6010 specified binaries and symlinks.
6013 This produces a tarball that follows the
6014 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
6015 Docker Image Specification}. The ``repository name'' as it appears in
6016 the output of the @command{docker images} command is computed from
6017 package names passed on the command line or in the manifest file.
6020 This produces a SquashFS image containing all the specified binaries and
6021 symlinks, as well as empty mount points for virtual file systems like
6025 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
6026 For that reason, @command{guix pack -f squashfs} always implies @code{-S
6027 /bin=bin}. Thus, your @command{guix pack} invocation must always start
6028 with something like:
6031 guix pack -f squashfs bash @dots{}
6034 If you forget the @code{bash} (or similar) package, @command{singularity
6035 run} and @command{singularity exec} will fail with an unhelpful ``no
6036 such file or directory'' message.
6040 @cindex relocatable binaries
6043 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
6044 anywhere in the file system hierarchy and run from there.
6046 When this option is passed once, the resulting binaries require support for
6047 @dfn{user namespaces} in the kernel Linux; when passed
6048 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
6049 PRoot support, can be thought of as the abbreviation of ``Really
6050 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
6051 other techniques if user namespaces are unavailable, and essentially
6052 work anywhere---see below for the implications.
6054 For example, if you create a pack containing Bash with:
6057 guix pack -RR -S /mybin=bin bash
6061 ...@: you can copy that pack to a machine that lacks Guix, and from your
6062 home directory as a normal user, run:
6070 In that shell, if you type @code{ls /gnu/store}, you'll notice that
6071 @file{/gnu/store} shows up and contains all the dependencies of
6072 @code{bash}, even though the machine actually lacks @file{/gnu/store}
6073 altogether! That is probably the simplest way to deploy Guix-built
6074 software on a non-Guix machine.
6077 By default, relocatable binaries rely on the @dfn{user namespace} feature of
6078 the kernel Linux, which allows unprivileged users to mount or change root.
6079 Old versions of Linux did not support it, and some GNU/Linux distributions
6082 To produce relocatable binaries that work even in the absence of user
6083 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
6084 case, binaries will try user namespace support and fall back to another
6085 @dfn{execution engine} if user namespaces are not supported. The
6086 following execution engines are supported:
6090 Try user namespaces and fall back to PRoot if user namespaces are not
6091 supported (see below).
6094 Try user namespaces and fall back to Fakechroot if user namespaces are
6095 not supported (see below).
6098 Run the program through user namespaces and abort if they are not
6102 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
6103 provides the necessary
6104 support for file system virtualization. It achieves that by using the
6105 @code{ptrace} system call on the running program. This approach has the
6106 advantage to work without requiring special kernel support, but it incurs
6107 run-time overhead every time a system call is made.
6110 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
6111 Fakechroot} virtualizes file system accesses by intercepting calls to C
6112 library functions such as @code{open}, @code{stat}, @code{exec}, and so
6113 on. Unlike PRoot, it incurs very little overhead. However, it does not
6114 always work: for example, some file system accesses made from within the
6115 C library are not intercepted, and file system accesses made @i{via}
6116 direct syscalls are not intercepted either, leading to erratic behavior.
6119 @vindex GUIX_EXECUTION_ENGINE
6120 When running a wrapped program, you can explicitly request one of the
6121 execution engines listed above by setting the
6122 @env{GUIX_EXECUTION_ENGINE} environment variable accordingly.
6125 @cindex entry point, for Docker images
6126 @item --entry-point=@var{command}
6127 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
6128 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
6129 support it. @var{command} must be relative to the profile contained in the
6132 The entry point specifies the command that tools like @code{docker run} or
6133 @code{singularity run} automatically start by default. For example, you can
6137 guix pack -f docker --entry-point=bin/guile guile
6140 The resulting pack can easily be loaded and @code{docker run} with no extra
6141 arguments will spawn @code{bin/guile}:
6144 docker load -i pack.tar.gz
6145 docker run @var{image-id}
6148 @item --expression=@var{expr}
6149 @itemx -e @var{expr}
6150 Consider the package @var{expr} evaluates to.
6152 This has the same purpose as the same-named option in @command{guix
6153 build} (@pxref{Additional Build Options, @option{--expression} in
6154 @command{guix build}}).
6156 @item --manifest=@var{file}
6157 @itemx -m @var{file}
6158 Use the packages contained in the manifest object returned by the Scheme
6159 code in @var{file}. This option can be repeated several times, in which
6160 case the manifests are concatenated.
6162 This has a similar purpose as the same-named option in @command{guix
6163 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
6164 same manifest files. It allows you to define a collection of packages
6165 once and use it both for creating profiles and for creating archives
6166 for use on machines that do not have Guix installed. Note that you can
6167 specify @emph{either} a manifest file @emph{or} a list of packages,
6170 @item --system=@var{system}
6171 @itemx -s @var{system}
6172 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
6173 the system type of the build host.
6175 @item --target=@var{triplet}
6176 @cindex cross-compilation
6177 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
6178 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
6179 configuration triplets,, autoconf, Autoconf}).
6181 @item --compression=@var{tool}
6182 @itemx -C @var{tool}
6183 Compress the resulting tarball using @var{tool}---one of @code{gzip},
6184 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
6187 @item --symlink=@var{spec}
6188 @itemx -S @var{spec}
6189 Add the symlinks specified by @var{spec} to the pack. This option can
6190 appear several times.
6192 @var{spec} has the form @code{@var{source}=@var{target}}, where
6193 @var{source} is the symlink that will be created and @var{target} is the
6196 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
6197 symlink pointing to the @file{bin} sub-directory of the profile.
6199 @item --save-provenance
6200 Save provenance information for the packages passed on the command line.
6201 Provenance information includes the URL and commit of the channels in use
6204 Provenance information is saved in the
6205 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
6206 usual package metadata---the name and version of each package, their
6207 propagated inputs, and so on. It is useful information to the recipient of
6208 the pack, who then knows how the pack was (supposedly) obtained.
6210 This option is not enabled by default because, like timestamps, provenance
6211 information contributes nothing to the build process. In other words, there
6212 is an infinity of channel URLs and commit IDs that can lead to the same pack.
6213 Recording such ``silent'' metadata in the output thus potentially breaks the
6214 source-to-binary bitwise reproducibility property.
6216 @item --root=@var{file}
6217 @itemx -r @var{file}
6218 @cindex garbage collector root, for packs
6219 Make @var{file} a symlink to the resulting pack, and register it as a garbage
6222 @item --localstatedir
6223 @itemx --profile-name=@var{name}
6224 Include the ``local state directory'', @file{/var/guix}, in the resulting
6225 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
6226 profile---by default @var{name} is @code{guix-profile}, which corresponds to
6227 @file{~root/.guix-profile}.
6229 @file{/var/guix} contains the store database (@pxref{The Store}) as well
6230 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
6231 the pack means that the store is ``complete'' and manageable by Guix;
6232 not providing it pack means that the store is ``dead'': items cannot be
6233 added to it or removed from it after extraction of the pack.
6235 One use case for this is the Guix self-contained binary tarball
6236 (@pxref{Binary Installation}).
6240 Print the name of the derivation that builds the pack.
6243 Use the bootstrap binaries to build the pack. This option is only
6244 useful to Guix developers.
6247 In addition, @command{guix pack} supports all the common build options
6248 (@pxref{Common Build Options}) and all the package transformation
6249 options (@pxref{Package Transformation Options}).
6252 @node The GCC toolchain
6253 @section The GCC toolchain
6257 @cindex linker wrapper
6258 @cindex toolchain, for C development
6259 @cindex toolchain, for Fortran development
6261 If you need a complete toolchain for compiling and linking C or C++
6262 source code, use the @code{gcc-toolchain} package. This package
6263 provides a complete GCC toolchain for C/C++ development, including GCC
6264 itself, the GNU C Library (headers and binaries, plus debugging symbols
6265 in the @code{debug} output), Binutils, and a linker wrapper.
6267 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
6268 passed to the linker, add corresponding @code{-rpath} arguments, and
6269 invoke the actual linker with this new set of arguments. You can instruct the
6270 wrapper to refuse to link against libraries not in the store by setting the
6271 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
6273 The package @code{gfortran-toolchain} provides a complete GCC toolchain
6274 for Fortran development. For other languages, please use
6275 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
6278 @node Invoking guix git authenticate
6279 @section Invoking @command{guix git authenticate}
6281 The @command{guix git authenticate} command authenticates a Git checkout
6282 following the same rule as for channels (@pxref{channel-authentication,
6283 channel authentication}). That is, starting from a given commit, it
6284 ensures that all subsequent commits are signed by an OpenPGP key whose
6285 fingerprint appears in the @file{.guix-authorizations} file of its
6288 You will find this command useful if you maintain a channel. But in
6289 fact, this authentication mechanism is useful in a broader context, so
6290 you might want to use it for Git repositories that have nothing to do
6293 The general syntax is:
6296 guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
6299 By default, this command authenticates the Git checkout in the current
6300 directory; it outputs nothing and exits with exit code zero on success
6301 and non-zero on failure. @var{commit} above denotes the first commit
6302 where authentication takes place, and @var{signer} is the OpenPGP
6303 fingerprint of public key used to sign @var{commit}. Together, they
6304 form a ``channel introduction'' (@pxref{channel-authentication, channel
6305 introduction}). The options below allow you to fine-tune the process.
6308 @item --repository=@var{directory}
6309 @itemx -r @var{directory}
6310 Open the Git repository in @var{directory} instead of the current
6313 @item --keyring=@var{reference}
6314 @itemx -k @var{reference}
6315 Load OpenPGP keyring from @var{reference}, the reference of a branch
6316 such as @code{origin/keyring} or @code{my-keyring}. The branch must
6317 contain OpenPGP public keys in @file{.key} files, either in binary form
6318 or ``ASCII-armored''. By default the keyring is loaded from the branch
6319 named @code{keyring}.
6322 Display commit signing statistics upon completion.
6324 @item --cache-key=@var{key}
6325 Previously-authenticated commits are cached in a file under
6326 @file{~/.cache/guix/authentication}. This option forces the cache to be
6327 stored in file @var{key} in that directory.
6329 @item --historical-authorizations=@var{file}
6330 By default, any commit whose parent commit(s) lack the
6331 @file{.guix-authorizations} file is considered inauthentic. In
6332 contrast, this option considers the authorizations in @var{file} for any
6333 commit that lacks @file{.guix-authorizations}. The format of @var{file}
6334 is the same as that of @file{.guix-authorizations}
6335 (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
6339 @c *********************************************************************
6340 @node Programming Interface
6341 @chapter Programming Interface
6343 GNU Guix provides several Scheme programming interfaces (APIs) to
6344 define, build, and query packages. The first interface allows users to
6345 write high-level package definitions. These definitions refer to
6346 familiar packaging concepts, such as the name and version of a package,
6347 its build system, and its dependencies. These definitions can then be
6348 turned into concrete build actions.
6350 Build actions are performed by the Guix daemon, on behalf of users. In a
6351 standard setup, the daemon has write access to the store---the
6352 @file{/gnu/store} directory---whereas users do not. The recommended
6353 setup also has the daemon perform builds in chroots, under specific
6354 build users, to minimize interference with the rest of the system.
6357 Lower-level APIs are available to interact with the daemon and the
6358 store. To instruct the daemon to perform a build action, users actually
6359 provide it with a @dfn{derivation}. A derivation is a low-level
6360 representation of the build actions to be taken, and the environment in
6361 which they should occur---derivations are to package definitions what
6362 assembly is to C programs. The term ``derivation'' comes from the fact
6363 that build results @emph{derive} from them.
6365 This chapter describes all these APIs in turn, starting from high-level
6366 package definitions.
6369 * Package Modules:: Packages from the programmer's viewpoint.
6370 * Defining Packages:: Defining new packages.
6371 * Defining Package Variants:: Customizing packages.
6372 * Build Systems:: Specifying how packages are built.
6373 * Build Phases:: Phases of the build process of a package.
6374 * Build Utilities:: Helpers for your package definitions and more.
6375 * The Store:: Manipulating the package store.
6376 * Derivations:: Low-level interface to package derivations.
6377 * The Store Monad:: Purely functional interface to the store.
6378 * G-Expressions:: Manipulating build expressions.
6379 * Invoking guix repl:: Programming Guix in Guile
6382 @node Package Modules
6383 @section Package Modules
6385 From a programming viewpoint, the package definitions of the
6386 GNU distribution are provided by Guile modules in the @code{(gnu packages
6387 @dots{})} name space@footnote{Note that packages under the @code{(gnu
6388 packages @dots{})} module name space are not necessarily ``GNU
6389 packages''. This module naming scheme follows the usual Guile module
6390 naming convention: @code{gnu} means that these modules are distributed
6391 as part of the GNU system, and @code{packages} identifies modules that
6392 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
6393 Reference Manual}). For instance, the @code{(gnu packages emacs)}
6394 module exports a variable named @code{emacs}, which is bound to a
6395 @code{<package>} object (@pxref{Defining Packages}).
6397 The @code{(gnu packages @dots{})} module name space is
6398 automatically scanned for packages by the command-line tools. For
6399 instance, when running @code{guix install emacs}, all the @code{(gnu
6400 packages @dots{})} modules are scanned until one that exports a package
6401 object whose name is @code{emacs} is found. This package search
6402 facility is implemented in the @code{(gnu packages)} module.
6404 @cindex customization, of packages
6405 @cindex package module search path
6406 Users can store package definitions in modules with different
6407 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
6408 name and module name must match. For instance, the @code{(my-packages
6409 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
6410 relative to the load path specified with @option{--load-path} or
6411 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
6412 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
6413 these package definitions visible to the user interfaces:
6417 By adding the directory containing your package modules to the search path
6418 with the @code{-L} flag of @command{guix package} and other commands
6419 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
6420 environment variable described below.
6423 By defining a @dfn{channel} and configuring @command{guix pull} so that it
6424 pulls from it. A channel is essentially a Git repository containing package
6425 modules. @xref{Channels}, for more information on how to define and use
6429 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
6431 @defvr {Environment Variable} GUIX_PACKAGE_PATH
6432 This is a colon-separated list of directories to search for additional
6433 package modules. Directories listed in this variable take precedence
6434 over the own modules of the distribution.
6437 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
6438 each package is built based solely on other packages in the
6439 distribution. The root of this dependency graph is a small set of
6440 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
6441 bootstrap)} module. For more information on bootstrapping,
6442 @pxref{Bootstrapping}.
6444 @node Defining Packages
6445 @section Defining Packages
6447 The high-level interface to package definitions is implemented in the
6448 @code{(guix packages)} and @code{(guix build-system)} modules. As an
6449 example, the package definition, or @dfn{recipe}, for the GNU Hello
6450 package looks like this:
6453 (define-module (gnu packages hello)
6454 #:use-module (guix packages)
6455 #:use-module (guix download)
6456 #:use-module (guix build-system gnu)
6457 #:use-module (guix licenses)
6458 #:use-module (gnu packages gawk))
6460 (define-public hello
6466 (uri (string-append "mirror://gnu/hello/hello-" version
6470 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
6471 (build-system gnu-build-system)
6472 (arguments '(#:configure-flags '("--enable-silent-rules")))
6473 (inputs `(("gawk" ,gawk)))
6474 (synopsis "Hello, GNU world: An example GNU package")
6475 (description "Guess what GNU Hello prints!")
6476 (home-page "https://www.gnu.org/software/hello/")
6481 Without being a Scheme expert, the reader may have guessed the meaning
6482 of the various fields here. This expression binds the variable
6483 @code{hello} to a @code{<package>} object, which is essentially a record
6484 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
6485 This package object can be inspected using procedures found in the
6486 @code{(guix packages)} module; for instance, @code{(package-name hello)}
6487 returns---surprise!---@code{"hello"}.
6489 With luck, you may be able to import part or all of the definition of
6490 the package you are interested in from another repository, using the
6491 @code{guix import} command (@pxref{Invoking guix import}).
6493 In the example above, @code{hello} is defined in a module of its own,
6494 @code{(gnu packages hello)}. Technically, this is not strictly
6495 necessary, but it is convenient to do so: all the packages defined in
6496 modules under @code{(gnu packages @dots{})} are automatically known to
6497 the command-line tools (@pxref{Package Modules}).
6499 There are a few points worth noting in the above package definition:
6503 The @code{source} field of the package is an @code{<origin>} object
6504 (@pxref{origin Reference}, for the complete reference).
6505 Here, the @code{url-fetch} method from @code{(guix download)} is used,
6506 meaning that the source is a file to be downloaded over FTP or HTTP.
6508 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
6509 the GNU mirrors defined in @code{(guix download)}.
6511 The @code{sha256} field specifies the expected SHA256 hash of the file
6512 being downloaded. It is mandatory, and allows Guix to check the
6513 integrity of the file. The @code{(base32 @dots{})} form introduces the
6514 base32 representation of the hash. You can obtain this information with
6515 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
6516 hash} (@pxref{Invoking guix hash}).
6519 When needed, the @code{origin} form can also have a @code{patches} field
6520 listing patches to be applied, and a @code{snippet} field giving a
6521 Scheme expression to modify the source code.
6524 @cindex GNU Build System
6525 The @code{build-system} field specifies the procedure to build the
6526 package (@pxref{Build Systems}). Here, @code{gnu-build-system}
6527 represents the familiar GNU Build System, where packages may be
6528 configured, built, and installed with the usual @code{./configure &&
6529 make && make check && make install} command sequence.
6531 When you start packaging non-trivial software, you may need tools to
6532 manipulate those build phases, manipulate files, and so on. @xref{Build
6533 Utilities}, for more on this.
6536 The @code{arguments} field specifies options for the build system
6537 (@pxref{Build Systems}). Here it is interpreted by
6538 @code{gnu-build-system} as a request run @file{configure} with the
6539 @option{--enable-silent-rules} flag.
6545 What about these quote (@code{'}) characters? They are Scheme syntax to
6546 introduce a literal list; @code{'} is synonymous with @code{quote}.
6547 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
6548 for details. Here the value of the @code{arguments} field is a list of
6549 arguments passed to the build system down the road, as with @code{apply}
6550 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
6553 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
6554 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
6555 @code{#:configure-flags} is a keyword used to pass a keyword argument
6556 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
6560 The @code{inputs} field specifies inputs to the build process---i.e.,
6561 build-time or run-time dependencies of the package. Here, we define an
6562 input called @code{"gawk"} whose value is that of the @code{gawk}
6563 variable; @code{gawk} is itself bound to a @code{<package>} object.
6565 @cindex backquote (quasiquote)
6568 @cindex comma (unquote)
6572 @findex unquote-splicing
6573 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
6574 us to introduce a literal list in the @code{inputs} field, while
6575 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
6576 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
6579 Note that GCC, Coreutils, Bash, and other essential tools do not need to
6580 be specified as inputs here. Instead, @code{gnu-build-system} takes care
6581 of ensuring that they are present (@pxref{Build Systems}).
6583 However, any other dependencies need to be specified in the
6584 @code{inputs} field. Any dependency not specified here will simply be
6585 unavailable to the build process, possibly leading to a build failure.
6588 @xref{package Reference}, for a full description of possible fields.
6590 Once a package definition is in place, the
6591 package may actually be built using the @code{guix build} command-line
6592 tool (@pxref{Invoking guix build}), troubleshooting any build failures
6593 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
6594 package definition using the @command{guix edit} command
6595 (@pxref{Invoking guix edit}).
6596 @xref{Packaging Guidelines}, for
6597 more information on how to test package definitions, and
6598 @ref{Invoking guix lint}, for information on how to check a definition
6599 for style conformance.
6600 @vindex GUIX_PACKAGE_PATH
6601 Lastly, @pxref{Channels}, for information
6602 on how to extend the distribution by adding your own package definitions
6605 Finally, updating the package definition to a new upstream version
6606 can be partly automated by the @command{guix refresh} command
6607 (@pxref{Invoking guix refresh}).
6609 Behind the scenes, a derivation corresponding to the @code{<package>}
6610 object is first computed by the @code{package-derivation} procedure.
6611 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
6612 The build actions it prescribes may then be realized by using the
6613 @code{build-derivations} procedure (@pxref{The Store}).
6615 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
6616 Return the @code{<derivation>} object of @var{package} for @var{system}
6617 (@pxref{Derivations}).
6619 @var{package} must be a valid @code{<package>} object, and @var{system}
6620 must be a string denoting the target system type---e.g.,
6621 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
6622 must be a connection to the daemon, which operates on the store
6623 (@pxref{The Store}).
6627 @cindex cross-compilation
6628 Similarly, it is possible to compute a derivation that cross-builds a
6629 package for some other system:
6631 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
6632 @var{package} @var{target} [@var{system}]
6633 Return the @code{<derivation>} object of @var{package} cross-built from
6634 @var{system} to @var{target}.
6636 @var{target} must be a valid GNU triplet denoting the target hardware
6637 and operating system, such as @code{"aarch64-linux-gnu"}
6638 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
6641 Once you have package definitions, you can easily define @emph{variants}
6642 of those packages. @xref{Defining Package Variants}, for more on that.
6645 * package Reference:: The package data type.
6646 * origin Reference:: The origin data type.
6650 @node package Reference
6651 @subsection @code{package} Reference
6653 This section summarizes all the options available in @code{package}
6654 declarations (@pxref{Defining Packages}).
6656 @deftp {Data Type} package
6657 This is the data type representing a package recipe.
6661 The name of the package, as a string.
6663 @item @code{version}
6664 The version of the package, as a string.
6667 An object telling how the source code for the package should be
6668 acquired. Most of the time, this is an @code{origin} object, which
6669 denotes a file fetched from the Internet (@pxref{origin Reference}). It
6670 can also be any other ``file-like'' object such as a @code{local-file},
6671 which denotes a file from the local file system (@pxref{G-Expressions,
6672 @code{local-file}}).
6674 @item @code{build-system}
6675 The build system that should be used to build the package (@pxref{Build
6678 @item @code{arguments} (default: @code{'()})
6679 The arguments that should be passed to the build system. This is a
6680 list, typically containing sequential keyword-value pairs.
6682 @item @code{inputs} (default: @code{'()})
6683 @itemx @code{native-inputs} (default: @code{'()})
6684 @itemx @code{propagated-inputs} (default: @code{'()})
6685 @cindex inputs, of packages
6686 These fields list dependencies of the package. Each one is a list of
6687 tuples, where each tuple has a label for the input (a string) as its
6688 first element, a package, origin, or derivation as its second element,
6689 and optionally the name of the output thereof that should be used, which
6690 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
6691 more on package outputs). For example, the list below specifies three
6695 `(("libffi" ,libffi)
6696 ("libunistring" ,libunistring)
6697 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
6700 @cindex cross compilation, package dependencies
6701 The distinction between @code{native-inputs} and @code{inputs} is
6702 necessary when considering cross-compilation. When cross-compiling,
6703 dependencies listed in @code{inputs} are built for the @emph{target}
6704 architecture; conversely, dependencies listed in @code{native-inputs}
6705 are built for the architecture of the @emph{build} machine.
6707 @code{native-inputs} is typically used to list tools needed at
6708 build time, but not at run time, such as Autoconf, Automake, pkg-config,
6709 Gettext, or Bison. @command{guix lint} can report likely mistakes in
6710 this area (@pxref{Invoking guix lint}).
6712 @anchor{package-propagated-inputs}
6713 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
6714 specified packages will be automatically installed to profiles
6715 (@pxref{Features, the role of profiles in Guix}) alongside the package
6716 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
6717 package}}, for information on how @command{guix package} deals with
6720 For example this is necessary when packaging a C/C++ library that needs
6721 headers of another library to compile, or when a pkg-config file refers
6722 to another one @i{via} its @code{Requires} field.
6724 Another example where @code{propagated-inputs} is useful is for languages
6725 that lack a facility to record the run-time search path akin to the
6726 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
6727 more. When packaging libraries written in those languages, ensure they
6728 can find library code they depend on at run time by listing run-time
6729 dependencies in @code{propagated-inputs} rather than @code{inputs}.
6731 @item @code{outputs} (default: @code{'("out")})
6732 The list of output names of the package. @xref{Packages with Multiple
6733 Outputs}, for typical uses of additional outputs.
6735 @item @code{native-search-paths} (default: @code{'()})
6736 @itemx @code{search-paths} (default: @code{'()})
6737 A list of @code{search-path-specification} objects describing
6738 search-path environment variables honored by the package.
6740 @item @code{replacement} (default: @code{#f})
6741 This must be either @code{#f} or a package object that will be used as a
6742 @dfn{replacement} for this package. @xref{Security Updates, grafts},
6745 @item @code{synopsis}
6746 A one-line description of the package.
6748 @item @code{description}
6749 A more elaborate description of the package.
6751 @item @code{license}
6752 @cindex license, of packages
6753 The license of the package; a value from @code{(guix licenses)},
6754 or a list of such values.
6756 @item @code{home-page}
6757 The URL to the home-page of the package, as a string.
6759 @item @code{supported-systems} (default: @code{%supported-systems})
6760 The list of systems supported by the package, as strings of the form
6761 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
6763 @item @code{location} (default: source location of the @code{package} form)
6764 The source location of the package. It is useful to override this when
6765 inheriting from another package, in which case this field is not
6766 automatically corrected.
6770 @deffn {Scheme Syntax} this-package
6771 When used in the @emph{lexical scope} of a package field definition, this
6772 identifier resolves to the package being defined.
6774 The example below shows how to add a package as a native input of itself when
6782 ;; When cross-compiled, Guile, for example, depends on
6783 ;; a native version of itself. Add it here.
6784 (native-inputs (if (%current-target-system)
6785 `(("self" ,this-package))
6789 It is an error to refer to @code{this-package} outside a package definition.
6792 Because packages are regular Scheme objects that capture a complete
6793 dependency graph and associated build procedures, it is often useful to
6794 write procedures that take a package and return a modified version
6795 thereof according to some parameters. Below are a few examples.
6797 @cindex tool chain, choosing a package's tool chain
6798 @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
6799 Return a variant of @var{package} that uses @var{toolchain} instead of
6800 the default GNU C/C++ toolchain. @var{toolchain} must be a list of
6801 inputs (label/package tuples) providing equivalent functionality, such
6802 as the @code{gcc-toolchain} package.
6804 The example below returns a variant of the @code{hello} package built
6805 with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
6806 GNU C Library) instead of the default tool chain:
6809 (let ((toolchain (specification->package "gcc-toolchain@@10")))
6810 (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
6813 The build tool chain is part of the @dfn{implicit inputs} of
6814 packages---it's usually not listed as part of the various ``inputs''
6815 fields and is instead pulled in by the build system. Consequently, this
6816 procedure works by changing the build system of @var{package} so that it
6817 pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
6818 for more on build systems.
6821 @node origin Reference
6822 @subsection @code{origin} Reference
6824 This section documents @dfn{origins}. An @code{origin} declaration
6825 specifies data that must be ``produced''---downloaded, usually---and
6826 whose content hash is known in advance. Origins are primarily used to
6827 represent the source code of packages (@pxref{Defining Packages}). For
6828 that reason, the @code{origin} form allows you to declare patches to
6829 apply to the original source code as well as code snippets to modify it.
6831 @deftp {Data Type} origin
6832 This is the data type representing a source code origin.
6836 An object containing the URI of the source. The object type depends on
6837 the @code{method} (see below). For example, when using the
6838 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
6839 values are: a URL represented as a string, or a list thereof.
6841 @cindex fixed-output derivations, for download
6843 A monadic procedure that handles the given URI@. The procedure must
6844 accept at least three arguments: the value of the @code{uri} field and
6845 the hash algorithm and hash value specified by the @code{hash} field.
6846 It must return a store item or a derivation in the store monad
6847 (@pxref{The Store Monad}); most methods return a fixed-output derivation
6848 (@pxref{Derivations}).
6850 Commonly used methods include @code{url-fetch}, which fetches data from
6851 a URL, and @code{git-fetch}, which fetches data from a Git repository
6855 A bytevector containing the SHA-256 hash of the source. This is
6856 equivalent to providing a @code{content-hash} SHA256 object in the
6857 @code{hash} field described below.
6860 The @code{content-hash} object of the source---see below for how to use
6861 @code{content-hash}.
6863 You can obtain this information using @code{guix download}
6864 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
6867 @item @code{file-name} (default: @code{#f})
6868 The file name under which the source code should be saved. When this is
6869 @code{#f}, a sensible default value will be used in most cases. In case
6870 the source is fetched from a URL, the file name from the URL will be
6871 used. For version control checkouts, it is recommended to provide the
6872 file name explicitly because the default is not very descriptive.
6874 @item @code{patches} (default: @code{'()})
6875 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
6876 file-like objects}) pointing to patches to be applied to the source.
6878 This list of patches must be unconditional. In particular, it cannot
6879 depend on the value of @code{%current-system} or
6880 @code{%current-target-system}.
6882 @item @code{snippet} (default: @code{#f})
6883 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
6884 in the source directory. This is a convenient way to modify the source,
6885 sometimes more convenient than a patch.
6887 @item @code{patch-flags} (default: @code{'("-p1")})
6888 A list of command-line flags that should be passed to the @code{patch}
6891 @item @code{patch-inputs} (default: @code{#f})
6892 Input packages or derivations to the patching process. When this is
6893 @code{#f}, the usual set of inputs necessary for patching are provided,
6894 such as GNU@tie{}Patch.
6896 @item @code{modules} (default: @code{'()})
6897 A list of Guile modules that should be loaded during the patching
6898 process and while running the code in the @code{snippet} field.
6900 @item @code{patch-guile} (default: @code{#f})
6901 The Guile package that should be used in the patching process. When
6902 this is @code{#f}, a sensible default is used.
6906 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
6907 Construct a content hash object for the given @var{algorithm}, and with
6908 @var{value} as its hash value. When @var{algorithm} is omitted, assume
6909 it is @code{sha256}.
6911 @var{value} can be a literal string, in which case it is base32-decoded,
6912 or it can be a bytevector.
6914 The following forms are all equivalent:
6917 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
6918 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
6920 (content-hash (base32
6921 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
6922 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
6926 Technically, @code{content-hash} is currently implemented as a macro.
6927 It performs sanity checks at macro-expansion time, when possible, such
6928 as ensuring that @var{value} has the right size for @var{algorithm}.
6931 As we have seen above, how exactly the data an origin refers to is
6932 retrieved is determined by its @code{method} field. The @code{(guix
6933 download)} module provides the most common method, @code{url-fetch},
6936 @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
6937 [name] [#:executable? #f]
6938 Return a fixed-output derivation that fetches data from @var{url} (a
6939 string, or a list of strings denoting alternate URLs), which is expected
6940 to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
6941 the file name is the base name of URL; optionally, @var{name} can
6942 specify a different file name. When @var{executable?} is true, make the
6943 downloaded file executable.
6945 When one of the URL starts with @code{mirror://}, then its host part is
6946 interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
6948 Alternatively, when URL starts with @code{file://}, return the
6949 corresponding file name in the store.
6952 Likewise, the @code{(guix git-download)} module defines the
6953 @code{git-fetch} origin method, which fetches data from a Git version
6954 control repository, and the @code{git-reference} data type to describe
6955 the repository and revision to fetch.
6957 @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
6958 Return a fixed-output derivation that fetches @var{ref}, a
6959 @code{<git-reference>} object. The output is expected to have recursive
6960 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
6961 the file name, or a generic name if @code{#f}.
6964 @deftp {Data Type} git-reference
6965 This data type represents a Git reference for @code{git-fetch} to
6970 The URL of the Git repository to clone.
6973 This string denotes either the commit to fetch (a hexadecimal string,
6974 either the full SHA1 commit or a ``short'' commit string; the latter is
6975 not recommended) or the tag to fetch.
6977 @item @code{recursive?} (default: @code{#f})
6978 This Boolean indicates whether to recursively fetch Git sub-modules.
6981 The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
6986 (url "https://git.savannah.gnu.org/git/hello.git")
6990 This is equivalent to the reference below, which explicitly names the
6995 (url "https://git.savannah.gnu.org/git/hello.git")
6996 (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
7000 For Mercurial repositories, the module @code{(guix hg-download)} defines
7001 the @code{hg-fetch} origin method and @code{hg-reference} data type for
7002 support of the Mercurial version control system.
7004 @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
7006 Return a fixed-output derivation that fetches @var{ref}, a
7007 @code{<hg-reference>} object. The output is expected to have recursive
7008 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7009 the file name, or a generic name if @code{#false}.
7012 @node Defining Package Variants
7013 @section Defining Package Variants
7015 @cindex customizing packages
7016 @cindex variants, of packages
7017 One of the nice things with Guix is that, given a package definition,
7018 you can easily @emph{derive} variants of that package---for a different
7019 upstream version, with different dependencies, different compilation
7020 options, and so on. Some of these custom packages can be defined
7021 straight from the command line (@pxref{Package Transformation Options}).
7022 This section describes how to define package variants in code. This can
7023 be useful in ``manifests'' (@pxref{profile-manifest,
7024 @option{--manifest}}) and in your own package collection
7025 (@pxref{Creating a Channel}), among others!
7027 @cindex inherit, for package definitions
7028 As discussed earlier, packages are first-class objects in the Scheme
7029 language. The @code{(guix packages)} module provides the @code{package}
7030 construct to define new package objects (@pxref{package Reference}).
7031 The easiest way to define a package variant is using the @code{inherit}
7032 keyword together with @code{package}. This allows you to inherit from a
7033 package definition while overriding the fields you want.
7035 For example, given the @code{hello} variable, which contains a
7036 definition for the current version of GNU@tie{}Hello, here's how you
7037 would define a variant for version 2.2 (released in 2006, it's
7041 (use-modules (gnu packages base)) ;for 'hello'
7049 (uri (string-append "mirror://gnu/hello/hello-" version
7053 "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
7056 The example above corresponds to what the @option{--with-source} package
7057 transformation option does. Essentially @code{hello-2.2} preserves all
7058 the fields of @code{hello}, except @code{version} and @code{source},
7059 which it overrides. Note that the original @code{hello} variable is
7060 still there, in the @code{(gnu packages base)} module, unchanged. When
7061 you define a custom package like this, you are really @emph{adding} a
7062 new package definition; the original one remains available.
7064 You can just as well define variants with a different set of
7065 dependencies than the original package. For example, the default
7066 @code{gdb} package depends on @code{guile}, but since that is an
7067 optional dependency, you can define a variant that removes that
7071 (use-modules (gnu packages gdb) ;for 'gdb'
7072 (srfi srfi-1)) ;for 'alist-delete'
7074 (define gdb-sans-guile
7077 (inputs (alist-delete "guile"
7078 (package-inputs gdb)))))
7081 The @code{alist-delete} call above removes the tuple from the
7082 @code{inputs} field that has @code{"guile"} as its first element
7083 (@pxref{SRFI-1 Association Lists,,, guile, GNU Guile Reference
7086 In some cases, you may find it useful to write functions
7087 (``procedures'', in Scheme parlance) that return a package based on some
7088 parameters. For example, consider the @code{luasocket} library for the
7089 Lua programming language. We want to create @code{luasocket} packages
7090 for major versions of Lua. One way to do that is to define a procedure
7091 that takes a Lua package and returns a @code{luasocket} package that
7095 (define (make-lua-socket name lua)
7096 ;; Return a luasocket package built with LUA.
7100 ;; several fields omitted
7103 (synopsis "Socket library for Lua")))
7105 (define-public lua5.1-socket
7106 (make-lua-socket "lua5.1-socket" lua-5.1))
7108 (define-public lua5.2-socket
7109 (make-lua-socket "lua5.2-socket" lua-5.2))
7112 Here we have defined packages @code{lua5.1-socket} and
7113 @code{lua5.2-socket} by calling @code{make-lua-socket} with different
7114 arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
7115 more info on procedures. Having top-level public definitions for these
7116 two packages means that they can be referred to from the command line
7117 (@pxref{Package Modules}).
7119 @cindex package transformations
7120 These are pretty simple package variants. As a convenience, the
7121 @code{(guix transformations)} module provides a high-level interface
7122 that directly maps to the more sophisticated package transformation
7123 options (@pxref{Package Transformation Options}):
7125 @deffn {Scheme Procedure} options->transformation @var{opts}
7126 Return a procedure that, when passed an object to build (package,
7127 derivation, etc.), applies the transformations specified by @var{opts} and returns
7128 the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
7131 ((with-branch . "guile-gcrypt=master")
7132 (without-tests . "libgcrypt"))
7135 Each symbol names a transformation and the corresponding string is an argument
7136 to that transformation.
7139 For instance, a manifest equivalent to this command:
7143 --with-branch=guile-gcrypt=master \
7144 --with-debug-info=zlib
7148 ... would look like this:
7151 (use-modules (guix transformations))
7154 ;; The package transformation procedure.
7155 (options->transformation
7156 '((with-branch . "guile-gcrypt=master")
7157 (with-debug-info . "zlib"))))
7160 (list (transform (specification->package "guix"))))
7163 @cindex input rewriting
7164 @cindex dependency graph rewriting
7165 The @code{options->transformation} procedure is convenient, but it's
7166 perhaps also not as flexible as you may like. How is it implemented?
7167 The astute reader probably noticed that most package transformation
7168 options go beyond the superficial changes shown in the first examples of
7169 this section: they involve @dfn{input rewriting}, whereby the dependency
7170 graph of a package is rewritten by replacing specific inputs by others.
7172 Dependency graph rewriting, for the purposes of swapping packages in the
7173 graph, is what the @code{package-input-rewriting} procedure in
7174 @code{(guix packages)} implements.
7176 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
7177 [@var{rewrite-name}] [#:deep? #t]
7178 Return a procedure that, when passed a package, replaces its direct and
7179 indirect dependencies, including implicit inputs when @var{deep?} is
7180 true, according to @var{replacements}. @var{replacements} is a list of
7181 package pairs; the first element of each pair is the package to replace,
7182 and the second one is the replacement.
7184 Optionally, @var{rewrite-name} is a one-argument procedure that takes
7185 the name of a package and returns its new name after rewrite.
7189 Consider this example:
7192 (define libressl-instead-of-openssl
7193 ;; This is a procedure to replace OPENSSL by LIBRESSL,
7195 (package-input-rewriting `((,openssl . ,libressl))))
7197 (define git-with-libressl
7198 (libressl-instead-of-openssl git))
7202 Here we first define a rewriting procedure that replaces @var{openssl}
7203 with @var{libressl}. Then we use it to define a @dfn{variant} of the
7204 @var{git} package that uses @var{libressl} instead of @var{openssl}.
7205 This is exactly what the @option{--with-input} command-line option does
7206 (@pxref{Package Transformation Options, @option{--with-input}}).
7208 The following variant of @code{package-input-rewriting} can match packages to
7209 be replaced by name rather than by identity.
7211 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
7212 Return a procedure that, given a package, applies the given
7213 @var{replacements} to all the package graph, including implicit inputs
7214 unless @var{deep?} is false. @var{replacements} is a list of
7215 spec/procedures pair; each spec is a package specification such as
7216 @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
7217 package and returns a replacement for that package.
7220 The example above could be rewritten this way:
7223 (define libressl-instead-of-openssl
7224 ;; Replace all the packages called "openssl" with LibreSSL.
7225 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
7228 The key difference here is that, this time, packages are matched by spec and
7229 not by identity. In other words, any package in the graph that is called
7230 @code{openssl} will be replaced.
7232 A more generic procedure to rewrite a package dependency graph is
7233 @code{package-mapping}: it supports arbitrary changes to nodes in the
7236 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
7237 Return a procedure that, given a package, applies @var{proc} to all the packages
7238 depended on and returns the resulting package. The procedure stops recursion
7239 when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
7240 applied to implicit inputs as well.
7245 @section Build Systems
7247 @cindex build system
7248 Each package definition specifies a @dfn{build system} and arguments for
7249 that build system (@pxref{Defining Packages}). This @code{build-system}
7250 field represents the build procedure of the package, as well as implicit
7251 dependencies of that build procedure.
7253 Build systems are @code{<build-system>} objects. The interface to
7254 create and manipulate them is provided by the @code{(guix build-system)}
7255 module, and actual build systems are exported by specific modules.
7257 @cindex bag (low-level package representation)
7258 Under the hood, build systems first compile package objects to
7259 @dfn{bags}. A @dfn{bag} is like a package, but with less
7260 ornamentation---in other words, a bag is a lower-level representation of
7261 a package, which includes all the inputs of that package, including some
7262 that were implicitly added by the build system. This intermediate
7263 representation is then compiled to a derivation (@pxref{Derivations}).
7264 The @code{package-with-c-toolchain} is an example of a way to change the
7265 implicit inputs that a package's build system pulls in (@pxref{package
7266 Reference, @code{package-with-c-toolchain}}).
7268 Build systems accept an optional list of @dfn{arguments}. In package
7269 definitions, these are passed @i{via} the @code{arguments} field
7270 (@pxref{Defining Packages}). They are typically keyword arguments
7271 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
7272 Guile Reference Manual}). The value of these arguments is usually
7273 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
7274 by the daemon (@pxref{Derivations}).
7276 The main build system is @code{gnu-build-system}, which implements the
7277 standard build procedure for GNU and many other packages. It
7278 is provided by the @code{(guix build-system gnu)} module.
7280 @defvr {Scheme Variable} gnu-build-system
7281 @code{gnu-build-system} represents the GNU Build System, and variants
7282 thereof (@pxref{Configuration, configuration and makefile conventions,,
7283 standards, GNU Coding Standards}).
7285 @cindex build phases
7286 In a nutshell, packages using it are configured, built, and installed with
7287 the usual @code{./configure && make && make check && make install}
7288 command sequence. In practice, a few additional steps are often needed.
7289 All these steps are split up in separate @dfn{phases},
7290 notably@footnote{Please see the @code{(guix build gnu-build-system)}
7291 modules for more details about the build phases.}:
7295 Unpack the source tarball, and change the current directory to the
7296 extracted source tree. If the source is actually a directory, copy it
7297 to the build tree, and enter that directory.
7299 @item patch-source-shebangs
7300 Patch shebangs encountered in source files so they refer to the right
7301 store file names. For instance, this changes @code{#!/bin/sh} to
7302 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
7305 Run the @file{configure} script with a number of default options, such
7306 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
7307 by the @code{#:configure-flags} argument.
7310 Run @code{make} with the list of flags specified with
7311 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
7312 (the default), build with @code{make -j}.
7315 Run @code{make check}, or some other target specified with
7316 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
7317 @code{#:parallel-tests?} argument is true (the default), run @code{make
7321 Run @code{make install} with the flags listed in @code{#:make-flags}.
7323 @item patch-shebangs
7324 Patch shebangs on the installed executable files.
7327 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
7328 is false), copying them to the @code{debug} output when available
7329 (@pxref{Installing Debugging Files}).
7332 @vindex %standard-phases
7333 The build-side module @code{(guix build gnu-build-system)} defines
7334 @code{%standard-phases} as the default list of build phases.
7335 @code{%standard-phases} is a list of symbol/procedure pairs, where the
7336 procedure implements the actual phase.
7338 @xref{Build Phases}, for more info on build phases and ways to customize
7341 In addition, this build system ensures that the ``standard'' environment
7342 for GNU packages is available. This includes tools such as GCC, libc,
7343 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
7344 build-system gnu)} module for a complete list). We call these the
7345 @dfn{implicit inputs} of a package, because package definitions do not
7346 have to mention them.
7349 Other @code{<build-system>} objects are defined to support other
7350 conventions and tools used by free software packages. They inherit most
7351 of @code{gnu-build-system}, and differ mainly in the set of inputs
7352 implicitly added to the build process, and in the list of phases
7353 executed. Some of these build systems are listed below.
7355 @defvr {Scheme Variable} ant-build-system
7356 This variable is exported by @code{(guix build-system ant)}. It
7357 implements the build procedure for Java packages that can be built with
7358 @url{https://ant.apache.org/, Ant build tool}.
7360 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
7361 provided by the @code{icedtea} package to the set of inputs. Different
7362 packages can be specified with the @code{#:ant} and @code{#:jdk}
7363 parameters, respectively.
7365 When the original package does not provide a suitable Ant build file,
7366 the parameter @code{#:jar-name} can be used to generate a minimal Ant
7367 build file @file{build.xml} with tasks to build the specified jar
7368 archive. In this case the parameter @code{#:source-dir} can be used to
7369 specify the source sub-directory, defaulting to ``src''.
7371 The @code{#:main-class} parameter can be used with the minimal ant
7372 buildfile to specify the main class of the resulting jar. This makes the
7373 jar file executable. The @code{#:test-include} parameter can be used to
7374 specify the list of junit tests to run. It defaults to
7375 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
7376 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
7377 because abstract classes cannot be run as tests.
7379 The parameter @code{#:build-target} can be used to specify the Ant task
7380 that should be run during the @code{build} phase. By default the
7381 ``jar'' task will be run.
7385 @defvr {Scheme Variable} android-ndk-build-system
7386 @cindex Android distribution
7387 @cindex Android NDK build system
7388 This variable is exported by @code{(guix build-system android-ndk)}. It
7389 implements a build procedure for Android NDK (native development kit)
7390 packages using a Guix-specific build process.
7392 The build system assumes that packages install their public interface
7393 (header) files to the subdirectory @file{include} of the @code{out} output and
7394 their libraries to the subdirectory @file{lib} the @code{out} output.
7396 It's also assumed that the union of all the dependencies of a package
7397 has no conflicting files.
7399 For the time being, cross-compilation is not supported - so right now
7400 the libraries and header files are assumed to be host tools.
7404 @defvr {Scheme Variable} asdf-build-system/source
7405 @defvrx {Scheme Variable} asdf-build-system/sbcl
7406 @defvrx {Scheme Variable} asdf-build-system/ecl
7408 These variables, exported by @code{(guix build-system asdf)}, implement
7409 build procedures for Common Lisp packages using
7410 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
7411 definition facility for Common Lisp programs and libraries.
7413 The @code{asdf-build-system/source} system installs the packages in
7414 source form, and can be loaded using any common lisp implementation, via
7415 ASDF@. The others, such as @code{asdf-build-system/sbcl}, install binary
7416 systems in the format which a particular implementation understands.
7417 These build systems can also be used to produce executable programs, or
7418 lisp images which contain a set of packages pre-loaded.
7420 The build system uses naming conventions. For binary packages, the
7421 package name should be prefixed with the lisp implementation, such as
7422 @code{sbcl-} for @code{asdf-build-system/sbcl}.
7424 Additionally, the corresponding source package should be labeled using
7425 the same convention as python packages (see @ref{Python Modules}), using
7426 the @code{cl-} prefix.
7428 In order to create executable programs and images, the build-side
7429 procedures @code{build-program} and @code{build-image} can be used.
7430 They should be called in a build phase after the
7431 @code{create-asdf-configuration} phase, so that the system which was
7432 just built can be used within the resulting image. @code{build-program}
7433 requires a list of Common Lisp expressions to be passed as the
7434 @code{#:entry-program} argument.
7436 By default, all the @file{.asd} files present in the sources are read to
7437 find system definitions. The @code{#:asd-files} parameter can be used
7438 to specify the list of @file{.asd} files to read. Furthermore, if the
7439 package defines a system for its tests in a separate file, it will be
7440 loaded before the tests are run if it is specified by the
7441 @code{#:test-asd-file} parameter. If it is not set, the files
7442 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
7443 and @code{test.asd} will be tried if they exist.
7445 If for some reason the package must be named in a different way than the
7446 naming conventions suggest, or if several systems must be compiled, the
7447 @code{#:asd-systems} parameter can be used to specify the list of system
7452 @defvr {Scheme Variable} cargo-build-system
7453 @cindex Rust programming language
7454 @cindex Cargo (Rust build system)
7455 This variable is exported by @code{(guix build-system cargo)}. It
7456 supports builds of packages using Cargo, the build tool of the
7457 @uref{https://www.rust-lang.org, Rust programming language}.
7459 It adds @code{rustc} and @code{cargo} to the set of inputs.
7460 A different Rust package can be specified with the @code{#:rust} parameter.
7462 Regular cargo dependencies should be added to the package definition similarly
7463 to other packages; those needed only at build time to native-inputs, others to
7464 inputs. If you need to add source-only crates then you should add them to via
7465 the @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
7466 spec can be a package or a source definition. Note that the spec must
7467 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
7468 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
7469 should be added to the package definition via the
7470 @code{#:cargo-development-inputs} parameter.
7472 In its @code{configure} phase, this build system will make any source inputs
7473 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
7474 parameters available to cargo. It will also remove an included
7475 @code{Cargo.lock} file to be recreated by @code{cargo} during the
7476 @code{build} phase. The @code{package} phase will run @code{cargo package}
7477 to create a source crate for future use. The @code{install} phase installs
7478 the binaries defined by the crate. Unless @code{install-source? #f} is
7479 defined it will also install a source crate repository of itself and unpacked
7480 sources, to ease in future hacking on rust packages.
7483 @defvr {Scheme Variable} chicken-build-system
7484 This variable is exported by @code{(guix build-system chicken)}. It
7485 builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
7486 ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
7487 gets compiled by a C compiler, in this case GCC.
7489 This build system adds @code{chicken} to the package inputs, as well as
7490 the packages of @code{gnu-build-system}.
7492 The build system can't (yet) deduce the egg's name automatically, so just like
7493 with @code{go-build-system} and its @code{#:import-path}, you should define
7494 @code{#:egg-name} in the package's @code{arguments} field.
7496 For example, if you are packaging the @code{srfi-1} egg:
7499 (arguments '(#:egg-name "srfi-1"))
7502 Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
7503 because CHICKEN doesn't embed absolute references in compiled eggs.
7504 Test dependencies should go to @code{native-inputs}, as usual.
7507 @defvr {Scheme Variable} copy-build-system
7508 This variable is exported by @code{(guix build-system copy)}. It
7509 supports builds of simple packages that don't require much compiling,
7510 mostly just moving files around.
7512 It adds much of the @code{gnu-build-system} packages to the set of
7513 inputs. Because of this, the @code{copy-build-system} does not require
7514 all the boilerplate code often needed for the
7515 @code{trivial-build-system}.
7517 To further simplify the file installation process, an
7518 @code{#:install-plan} argument is exposed to let the packager specify
7519 which files go where. The install plan is a list of @code{(@var{source}
7520 @var{target} [@var{filters}])}. @var{filters} are optional.
7523 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
7525 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
7526 @item Otherwise install @var{source} as @var{target}.
7529 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
7530 the trailing slash of @var{target} is implied with the same meaning
7533 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
7534 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
7535 @code{#:exclude-regexp}, only select files are installed depending on
7536 the filters. Each filters is specified by a list of strings.
7538 @item With @code{#:include}, install all the files which the path suffix matches
7539 at least one of the elements in the given list.
7540 @item With @code{#:include-regexp}, install all the files which the
7541 subpaths match at least one of the regular expressions in the given
7543 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
7544 are the complement of their inclusion counterpart. Without @code{#:include} flags,
7545 install all files but those matching the exclusion filters.
7546 If both inclusions and exclusions are specified, the exclusions are done
7547 on top of the inclusions.
7550 In all cases, the paths relative to @var{source} are preserved within
7557 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
7558 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
7559 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
7560 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
7561 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
7562 @file{share/my-app/sub/file}.
7563 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
7564 @file{share/my-app/file}.
7569 @cindex Clojure (programming language)
7570 @cindex simple Clojure build system
7571 @defvr {Scheme Variable} clojure-build-system
7572 This variable is exported by @code{(guix build-system clojure)}. It implements
7573 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
7574 using plain old @code{compile} in Clojure. Cross-compilation is not supported
7577 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
7578 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
7579 @code{#:zip} parameters, respectively.
7581 A list of source directories, test directories and jar names can be specified
7582 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
7583 parameters, respectively. Compile directory and main class can be specified
7584 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
7585 Other parameters are documented below.
7587 This build system is an extension of @code{ant-build-system}, but with the
7588 following phases changed:
7593 This phase calls @code{compile} in Clojure to compile source files and runs
7594 @command{jar} to create jars from both source files and compiled files
7595 according to the include list and exclude list specified in
7596 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
7597 has priority over the include list. These lists consist of symbols
7598 representing Clojure libraries or the special keyword @code{#:all} representing
7599 all Clojure libraries found under the source directories. The parameter
7600 @code{#:omit-source?} decides if source should be included into the jars.
7603 This phase runs tests according to the include list and exclude list specified
7604 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
7605 meanings are analogous to that of @code{#:aot-include} and
7606 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
7607 stands for all Clojure libraries found under the test directories. The
7608 parameter @code{#:tests?} decides if tests should be run.
7611 This phase installs all jars built previously.
7614 Apart from the above, this build system also contains an additional phase:
7619 This phase installs all top-level files with base name matching
7620 @code{%doc-regex}. A different regex can be specified with the
7621 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
7622 directories specified in @code{#:doc-dirs} are installed as well.
7626 @defvr {Scheme Variable} cmake-build-system
7627 This variable is exported by @code{(guix build-system cmake)}. It
7628 implements the build procedure for packages using the
7629 @url{https://www.cmake.org, CMake build tool}.
7631 It automatically adds the @code{cmake} package to the set of inputs.
7632 Which package is used can be specified with the @code{#:cmake}
7635 The @code{#:configure-flags} parameter is taken as a list of flags
7636 passed to the @command{cmake} command. The @code{#:build-type}
7637 parameter specifies in abstract terms the flags passed to the compiler;
7638 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
7639 debugging information''), which roughly means that code is compiled with
7640 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
7643 @defvr {Scheme Variable} dune-build-system
7644 This variable is exported by @code{(guix build-system dune)}. It
7645 supports builds of packages using @uref{https://dune.build/, Dune}, a build
7646 tool for the OCaml programming language. It is implemented as an extension
7647 of the @code{ocaml-build-system} which is described below. As such, the
7648 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
7651 It automatically adds the @code{dune} package to the set of inputs.
7652 Which package is used can be specified with the @code{#:dune}
7655 There is no @code{configure} phase because dune packages typically don't
7656 need to be configured. The @code{#:build-flags} parameter is taken as a
7657 list of flags passed to the @code{dune} command during the build.
7659 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
7660 command instead of the more recent @code{dune} command while building
7661 a package. Its default value is @code{#f}.
7663 The @code{#:package} parameter can be passed to specify a package name, which
7664 is useful when a package contains multiple packages and you want to build
7665 only one of them. This is equivalent to passing the @code{-p} argument to
7669 @defvr {Scheme Variable} go-build-system
7670 This variable is exported by @code{(guix build-system go)}. It
7671 implements a build procedure for Go packages using the standard
7672 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
7673 Go build mechanisms}.
7675 The user is expected to provide a value for the key @code{#:import-path}
7676 and, in some cases, @code{#:unpack-path}. The
7677 @url{https://golang.org/doc/code.html#ImportPaths, import path}
7678 corresponds to the file system path expected by the package's build
7679 scripts and any referring packages, and provides a unique way to
7680 refer to a Go package. It is typically based on a combination of the
7681 package source code's remote URI and file system hierarchy structure. In
7682 some cases, you will need to unpack the package's source code to a
7683 different directory structure than the one indicated by the import path,
7684 and @code{#:unpack-path} should be used in such cases.
7686 Packages that provide Go libraries should install their source code into
7687 the built output. The key @code{#:install-source?}, which defaults to
7688 @code{#t}, controls whether or not the source code is installed. It can
7689 be set to @code{#f} for packages that only provide executable files.
7692 @defvr {Scheme Variable} glib-or-gtk-build-system
7693 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
7694 is intended for use with packages making use of GLib or GTK+.
7696 This build system adds the following two phases to the ones defined by
7697 @code{gnu-build-system}:
7700 @item glib-or-gtk-wrap
7701 The phase @code{glib-or-gtk-wrap} ensures that programs in
7702 @file{bin/} are able to find GLib ``schemas'' and
7703 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
7704 modules}. This is achieved by wrapping the programs in launch scripts
7705 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
7706 environment variables.
7708 It is possible to exclude specific package outputs from that wrapping
7709 process by listing their names in the
7710 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
7711 when an output is known not to contain any GLib or GTK+ binaries, and
7712 where wrapping would gratuitously add a dependency of that output on
7715 @item glib-or-gtk-compile-schemas
7716 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
7717 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
7718 GSettings schemas} of GLib are compiled. Compilation is performed by the
7719 @command{glib-compile-schemas} program. It is provided by the package
7720 @code{glib:bin} which is automatically imported by the build system.
7721 The @code{glib} package providing @command{glib-compile-schemas} can be
7722 specified with the @code{#:glib} parameter.
7725 Both phases are executed after the @code{install} phase.
7728 @defvr {Scheme Variable} guile-build-system
7729 This build system is for Guile packages that consist exclusively of Scheme
7730 code and that are so lean that they don't even have a makefile, let alone a
7731 @file{configure} script. It compiles Scheme code using @command{guild
7732 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
7733 installs the @file{.scm} and @file{.go} files in the right place. It also
7734 installs documentation.
7736 This build system supports cross-compilation by using the
7737 @option{--target} option of @samp{guild compile}.
7739 Packages built with @code{guile-build-system} must provide a Guile package in
7740 their @code{native-inputs} field.
7743 @defvr {Scheme Variable} julia-build-system
7744 This variable is exported by @code{(guix build-system julia)}. It
7745 implements the build procedure used by @uref{https://julialang.org/,
7746 julia} packages, which essentially is similar to running @samp{julia -e
7747 'using Pkg; Pkg.add(package)'} in an environment where
7748 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
7749 Tests are run by calling @code{/test/runtests.jl}.
7751 The Julia package name is read from the file @file{Project.toml}. This
7752 value can be overridden by passing the argument @code{#:julia-file-name}
7753 (which must be correctly capitalized).
7755 For packages requiring shared library dependencies, you may need to write the
7756 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
7757 variable = /gnu/store/library.so} for each dependency, plus a void function
7758 @code{check_deps() = nothing}.
7760 Some older packages that aren't using @file{Package.toml} yet, will require
7761 this file to be created, too. The function @code{julia-create-package-toml}
7762 helps creating the file. You need to pass the outputs and the source of the
7763 package, it's name (the same as the @code{file-name} parameter), the package
7764 uuid, the package version, and a list of dependencies specified by their name
7768 @defvr {Scheme Variable} maven-build-system
7769 This variable is exported by @code{(guix build-system maven)}. It implements
7770 a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
7771 is a dependency and lifecycle management tool for Java. A user of Maven
7772 specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
7773 When Maven does not have one of the dependencies or plugins in its repository,
7774 it will download them and use them to build the package.
7776 The maven build system ensures that maven will not try to download any
7777 dependency by running in offline mode. Maven will fail if a dependency is
7778 missing. Before running Maven, the @file{pom.xml} (and subprojects) are
7779 modified to specify the version of dependencies and plugins that match the
7780 versions available in the guix build environment. Dependencies and plugins
7781 must be installed in the fake maven repository at @file{lib/m2}, and are
7782 symlinked into a proper repository before maven is run. Maven is instructed
7783 to use that repository for the build and installs built artifacts there.
7784 Changed files are copied to the @file{lib/m2} directory of the package output.
7786 You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
7787 or let the build system use the default @file{pom.xml} file in the sources.
7789 In case you need to specify a dependency's version manually, you can use the
7790 @code{#:local-packages} argument. It takes an association list where the key
7791 is the groupId of the package and its value is an association list where the
7792 key is the artifactId of the package and its value is the version you want to
7793 override in the @file{pom.xml}.
7795 Some packages use dependencies or plugins that are not useful at runtime nor
7796 at build time in Guix. You can alter the @file{pom.xml} file to remove them
7797 using the @code{#:exclude} argument. Its value is an association list where
7798 the key is the groupId of the plugin or dependency you want to remove, and
7799 the value is a list of artifactId you want to remove.
7801 You can override the default @code{jdk} and @code{maven} packages with the
7802 corresponding argument, @code{#:jdk} and @code{#:maven}.
7804 The @code{#:maven-plugins} argument is a list of maven plugins used during
7805 the build, with the same format as the @code{inputs} fields of the package
7806 declaration. Its default value is @code{(default-maven-plugins)} which is
7810 @defvr {Scheme Variable} minify-build-system
7811 This variable is exported by @code{(guix build-system minify)}. It
7812 implements a minification procedure for simple JavaScript packages.
7814 It adds @code{uglify-js} to the set of inputs and uses it to compress
7815 all JavaScript files in the @file{src} directory. A different minifier
7816 package can be specified with the @code{#:uglify-js} parameter, but it
7817 is expected that the package writes the minified code to the standard
7820 When the input JavaScript files are not all located in the @file{src}
7821 directory, the parameter @code{#:javascript-files} can be used to
7822 specify a list of file names to feed to the minifier.
7825 @defvr {Scheme Variable} ocaml-build-system
7826 This variable is exported by @code{(guix build-system ocaml)}. It implements
7827 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
7828 of choosing the correct set of commands to run for each package. OCaml
7829 packages can expect many different commands to be run. This build system will
7832 When the package has a @file{setup.ml} file present at the top-level, it will
7833 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
7834 @code{ocaml setup.ml -install}. The build system will assume that this file
7835 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
7836 care of setting the prefix and enabling tests if they are not disabled. You
7837 can pass configure and build flags with the @code{#:configure-flags} and
7838 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
7839 set of flags used to enable tests. The @code{#:use-make?} key can be used to
7840 bypass this system in the build and install phases.
7842 When the package has a @file{configure} file, it is assumed that it is a
7843 hand-made configure script that requires a different argument format than
7844 in the @code{gnu-build-system}. You can add more flags with the
7845 @code{#:configure-flags} key.
7847 When the package has a @file{Makefile} file (or @code{#:use-make?} is
7848 @code{#t}), it will be used and more flags can be passed to the build and
7849 install phases with the @code{#:make-flags} key.
7851 Finally, some packages do not have these files and use a somewhat standard
7852 location for its build system. In that case, the build system will run
7853 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
7854 providing the path to the required findlib module. Additional flags can
7855 be passed via the @code{#:build-flags} key. Install is taken care of by
7856 @command{opam-installer}. In this case, the @code{opam} package must
7857 be added to the @code{native-inputs} field of the package definition.
7859 Note that most OCaml packages assume they will be installed in the same
7860 directory as OCaml, which is not what we want in guix. In particular, they
7861 will install @file{.so} files in their module's directory, which is usually
7862 fine because it is in the OCaml compiler directory. In guix though, these
7863 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
7864 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
7865 @file{.so} libraries should be installed.
7868 @defvr {Scheme Variable} python-build-system
7869 This variable is exported by @code{(guix build-system python)}. It
7870 implements the more or less standard build procedure used by Python
7871 packages, which consists in running @code{python setup.py build} and
7872 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
7874 For packages that install stand-alone Python programs under @code{bin/},
7875 it takes care of wrapping these programs so that their @env{PYTHONPATH}
7876 environment variable points to all the Python libraries they depend on.
7878 Which Python package is used to perform the build can be specified with
7879 the @code{#:python} parameter. This is a useful way to force a package
7880 to be built for a specific version of the Python interpreter, which
7881 might be necessary if the package is only compatible with a single
7882 interpreter version.
7884 By default guix calls @code{setup.py} under control of
7885 @code{setuptools}, much like @command{pip} does. Some packages are not
7886 compatible with setuptools (and pip), thus you can disable this by
7887 setting the @code{#:use-setuptools?} parameter to @code{#f}.
7890 @defvr {Scheme Variable} perl-build-system
7891 This variable is exported by @code{(guix build-system perl)}. It
7892 implements the standard build procedure for Perl packages, which either
7893 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
7894 followed by @code{Build} and @code{Build install}; or in running
7895 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
7896 @code{make} and @code{make install}, depending on which of
7897 @code{Build.PL} or @code{Makefile.PL} is present in the package
7898 distribution. Preference is given to the former if both @code{Build.PL}
7899 and @code{Makefile.PL} exist in the package distribution. This
7900 preference can be reversed by specifying @code{#t} for the
7901 @code{#:make-maker?} parameter.
7903 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
7904 passes flags specified by the @code{#:make-maker-flags} or
7905 @code{#:module-build-flags} parameter, respectively.
7907 Which Perl package is used can be specified with @code{#:perl}.
7910 @defvr {Scheme Variable} renpy-build-system
7911 This variable is exported by @code{(guix build-system renpy)}. It implements
7912 the more or less standard build procedure used by Ren'py games, which consists
7913 of loading @code{#:game} once, thereby creating bytecode for it.
7915 It further creates a wrapper script in @code{bin/} and a desktop entry in
7916 @code{share/applications}, both of which can be used to launch the game.
7918 Which Ren'py package is used can be specified with @code{#:renpy}.
7919 Games can also be installed in outputs other than ``out'' by using
7923 @defvr {Scheme Variable} qt-build-system
7924 This variable is exported by @code{(guix build-system qt)}. It
7925 is intended for use with applications using Qt or KDE.
7927 This build system adds the following two phases to the ones defined by
7928 @code{cmake-build-system}:
7932 The phase @code{check-setup} prepares the environment for running
7933 the checks as commonly used by Qt test programs.
7934 For now this only sets some environment variables:
7935 @code{QT_QPA_PLATFORM=offscreen},
7936 @code{DBUS_FATAL_WARNINGS=0} and
7937 @code{CTEST_OUTPUT_ON_FAILURE=1}.
7939 This phase is added before the @code{check} phase.
7940 It's a separate phase to ease adjusting if necessary.
7943 The phase @code{qt-wrap}
7944 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
7945 and output. In case some path is found, all programs in the output's
7946 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
7947 are wrapped in scripts defining the necessary environment variables.
7949 It is possible to exclude specific package outputs from that wrapping process
7950 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
7951 This is useful when an output is known not to contain any Qt binaries, and
7952 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
7955 This phase is added after the @code{install} phase.
7959 @defvr {Scheme Variable} r-build-system
7960 This variable is exported by @code{(guix build-system r)}. It
7961 implements the build procedure used by @uref{https://r-project.org, R}
7962 packages, which essentially is little more than running @samp{R CMD
7963 INSTALL --library=/gnu/store/@dots{}} in an environment where
7964 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
7965 run after installation using the R function
7966 @code{tools::testInstalledPackage}.
7969 @defvr {Scheme Variable} rakudo-build-system
7970 This variable is exported by @code{(guix build-system rakudo)}. It
7971 implements the build procedure used by @uref{https://rakudo.org/,
7972 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
7973 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
7974 installs the binaries, library files and the resources, as well as wrap
7975 the files under the @code{bin/} directory. Tests can be skipped by
7976 passing @code{#f} to the @code{tests?} parameter.
7978 Which rakudo package is used can be specified with @code{rakudo}.
7979 Which perl6-tap-harness package used for the tests can be specified with
7980 @code{#:prove6} or removed by passing @code{#f} to the
7981 @code{with-prove6?} parameter.
7982 Which perl6-zef package used for tests and installing can be specified
7983 with @code{#:zef} or removed by passing @code{#f} to the
7984 @code{with-zef?} parameter.
7987 @defvr {Scheme Variable} texlive-build-system
7988 This variable is exported by @code{(guix build-system texlive)}. It is
7989 used to build TeX packages in batch mode with a specified engine. The
7990 build system sets the @env{TEXINPUTS} variable to find all TeX source
7991 files in the inputs.
7993 By default it runs @code{luatex} on all files ending on @code{ins}. A
7994 different engine and format can be specified with the
7995 @code{#:tex-format} argument. Different build targets can be specified
7996 with the @code{#:build-targets} argument, which expects a list of file
7997 names. The build system adds only @code{texlive-bin} and
7998 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
7999 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
8000 and @code{#:texlive-latex-base}, respectively.
8002 The @code{#:tex-directory} parameter tells the build system where to
8003 install the built files under the texmf tree.
8006 @defvr {Scheme Variable} ruby-build-system
8007 This variable is exported by @code{(guix build-system ruby)}. It
8008 implements the RubyGems build procedure used by Ruby packages, which
8009 involves running @code{gem build} followed by @code{gem install}.
8011 The @code{source} field of a package that uses this build system
8012 typically references a gem archive, since this is the format that Ruby
8013 developers use when releasing their software. The build system unpacks
8014 the gem archive, potentially patches the source, runs the test suite,
8015 repackages the gem, and installs it. Additionally, directories and
8016 tarballs may be referenced to allow building unreleased gems from Git or
8017 a traditional source release tarball.
8019 Which Ruby package is used can be specified with the @code{#:ruby}
8020 parameter. A list of additional flags to be passed to the @command{gem}
8021 command can be specified with the @code{#:gem-flags} parameter.
8024 @defvr {Scheme Variable} waf-build-system
8025 This variable is exported by @code{(guix build-system waf)}. It
8026 implements a build procedure around the @code{waf} script. The common
8027 phases---@code{configure}, @code{build}, and @code{install}---are
8028 implemented by passing their names as arguments to the @code{waf}
8031 The @code{waf} script is executed by the Python interpreter. Which
8032 Python package is used to run the script can be specified with the
8033 @code{#:python} parameter.
8036 @defvr {Scheme Variable} scons-build-system
8037 This variable is exported by @code{(guix build-system scons)}. It
8038 implements the build procedure used by the SCons software construction
8039 tool. This build system runs @code{scons} to build the package,
8040 @code{scons test} to run tests, and then @code{scons install} to install
8043 Additional flags to be passed to @code{scons} can be specified with the
8044 @code{#:scons-flags} parameter. The default build and install targets
8045 can be overridden with @code{#:build-targets} and
8046 @code{#:install-targets} respectively. The version of Python used to
8047 run SCons can be specified by selecting the appropriate SCons package
8048 with the @code{#:scons} parameter.
8051 @defvr {Scheme Variable} haskell-build-system
8052 This variable is exported by @code{(guix build-system haskell)}. It
8053 implements the Cabal build procedure used by Haskell packages, which
8054 involves running @code{runhaskell Setup.hs configure
8055 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
8056 Instead of installing the package by running @code{runhaskell Setup.hs
8057 install}, to avoid trying to register libraries in the read-only
8058 compiler store directory, the build system uses @code{runhaskell
8059 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
8060 addition, the build system generates the package documentation by
8061 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
8062 is passed. Optional Haddock parameters can be passed with the help of
8063 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
8064 not found, the build system looks for @code{Setup.lhs} instead.
8066 Which Haskell compiler is used can be specified with the @code{#:haskell}
8067 parameter which defaults to @code{ghc}.
8070 @defvr {Scheme Variable} dub-build-system
8071 This variable is exported by @code{(guix build-system dub)}. It
8072 implements the Dub build procedure used by D packages, which
8073 involves running @code{dub build} and @code{dub run}.
8074 Installation is done by copying the files manually.
8076 Which D compiler is used can be specified with the @code{#:ldc}
8077 parameter which defaults to @code{ldc}.
8080 @anchor{emacs-build-system}
8081 @defvr {Scheme Variable} emacs-build-system
8082 This variable is exported by @code{(guix build-system emacs)}. It
8083 implements an installation procedure similar to the packaging system
8084 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
8086 It first creates the @code{@code{package}-autoloads.el} file, then it
8087 byte compiles all Emacs Lisp files. Differently from the Emacs
8088 packaging system, the Info documentation files are moved to the standard
8089 documentation directory and the @file{dir} file is deleted. The Elisp
8090 package files are installed directly under @file{share/emacs/site-lisp}.
8093 @defvr {Scheme Variable} font-build-system
8094 This variable is exported by @code{(guix build-system font)}. It
8095 implements an installation procedure for font packages where upstream
8096 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
8097 need to be copied into place. It copies font files to standard
8098 locations in the output directory.
8101 @defvr {Scheme Variable} meson-build-system
8102 This variable is exported by @code{(guix build-system meson)}. It
8103 implements the build procedure for packages that use
8104 @url{https://mesonbuild.com, Meson} as their build system.
8106 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
8107 of inputs, and they can be changed with the parameters @code{#:meson}
8108 and @code{#:ninja} if needed. The default Meson is
8109 @code{meson-for-build}, which is special because it doesn't clear the
8110 @code{RUNPATH} of binaries and libraries when they are installed.
8112 This build system is an extension of @code{gnu-build-system}, but with the
8113 following phases changed to some specific for Meson:
8118 The phase runs @code{meson} with the flags specified in
8119 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
8120 @code{debugoptimized} unless something else is specified in
8121 @code{#:build-type}.
8124 The phase runs @code{ninja} to build the package in parallel by default, but
8125 this can be changed with @code{#:parallel-build?}.
8128 The phase runs @code{ninja} with the target specified in @code{#:test-target},
8129 which is @code{"test"} by default.
8132 The phase runs @code{ninja install} and can not be changed.
8135 Apart from that, the build system also adds the following phases:
8140 This phase ensures that all binaries can find the libraries they need.
8141 It searches for required libraries in subdirectories of the package being
8142 built, and adds those to @code{RUNPATH} where needed. It also removes
8143 references to libraries left over from the build phase by
8144 @code{meson-for-build}, such as test dependencies, that aren't actually
8145 required for the program to run.
8147 @item glib-or-gtk-wrap
8148 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
8149 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
8151 @item glib-or-gtk-compile-schemas
8152 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
8153 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
8157 @defvr {Scheme Variable} linux-module-build-system
8158 @code{linux-module-build-system} allows building Linux kernel modules.
8160 @cindex build phases
8161 This build system is an extension of @code{gnu-build-system}, but with the
8162 following phases changed:
8167 This phase configures the environment so that the Linux kernel's Makefile
8168 can be used to build the external kernel module.
8171 This phase uses the Linux kernel's Makefile in order to build the external
8175 This phase uses the Linux kernel's Makefile in order to install the external
8179 It is possible and useful to specify the Linux kernel to use for building
8180 the module (in the @code{arguments} form of a package using the
8181 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
8184 @defvr {Scheme Variable} node-build-system
8185 This variable is exported by @code{(guix build-system node)}. It
8186 implements the build procedure used by @uref{https://nodejs.org,
8187 Node.js}, which implements an approximation of the @code{npm install}
8188 command, followed by an @code{npm test} command.
8190 Which Node.js package is used to interpret the @code{npm} commands can
8191 be specified with the @code{#:node} parameter which defaults to
8195 Lastly, for packages that do not need anything as sophisticated, a
8196 ``trivial'' build system is provided. It is trivial in the sense that
8197 it provides basically no support: it does not pull any implicit inputs,
8198 and does not have a notion of build phases.
8200 @defvr {Scheme Variable} trivial-build-system
8201 This variable is exported by @code{(guix build-system trivial)}.
8203 This build system requires a @code{#:builder} argument. This argument
8204 must be a Scheme expression that builds the package output(s)---as
8205 with @code{build-expression->derivation} (@pxref{Derivations,
8206 @code{build-expression->derivation}}).
8210 @section Build Phases
8212 @cindex build phases, for packages
8213 Almost all package build systems implement a notion @dfn{build phases}:
8214 a sequence of actions that the build system executes, when you build the
8215 package, leading to the installed byproducts in the store. A notable
8216 exception is the ``bare-bones'' @code{trivial-build-system}
8217 (@pxref{Build Systems}).
8219 As discussed in the previous section, those build systems provide a
8220 standard list of phases. For @code{gnu-build-system}, the standard
8221 phases include an @code{unpack} phase to unpack the source code tarball,
8222 a @command{configure} phase to run @code{./configure}, a @code{build}
8223 phase to run @command{make}, and (among others) an @code{install} phase
8224 to run @command{make install}; @pxref{Build Systems}, for a more
8225 detailed view of these phases. Likewise, @code{cmake-build-system}
8226 inherits these phases, but its @code{configure} phase runs
8227 @command{cmake} instead of @command{./configure}. Other build systems,
8228 such as @code{python-build-system}, have a wholly different list of
8229 standard phases. All this code runs on the @dfn{build side}: it is
8230 evaluated when you actually build the package, in a dedicated build
8231 process spawned by the build daemon (@pxref{Invoking guix-daemon}).
8233 Build phases are represented as association lists or ``alists''
8234 (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
8235 each key is a symbol for the name of the phase and the associated value
8236 is a procedure that accepts an arbitrary number of arguments. By
8237 convention, those procedures receive information about the build in the
8238 form of @dfn{keyword parameters}, which they can use or ignore.
8240 For example, here is how @code{(guix build gnu-build-system)} defines
8241 @code{%standard-phases}, the variable holding its alist of build
8242 phases@footnote{We present a simplified view of those build phases, but
8243 do take a look at @code{(guix build gnu-build-system)} to see all the
8247 ;; The build phases of 'gnu-build-system'.
8249 (define* (unpack #:key source #:allow-other-keys)
8250 ;; Extract the source tarball.
8251 (invoke "tar" "xvf" source))
8253 (define* (configure #:key outputs #:allow-other-keys)
8254 ;; Run the 'configure' script. Install to output "out".
8255 (let ((out (assoc-ref outputs "out")))
8256 (invoke "./configure"
8257 (string-append "--prefix=" out))))
8259 (define* (build #:allow-other-keys)
8263 (define* (check #:key (test-target "check") (tests? #true)
8265 ;; Run the test suite.
8267 (invoke "make" test-target)
8268 (display "test suite not run\n")))
8270 (define* (install #:allow-other-keys)
8271 ;; Install files to the prefix 'configure' specified.
8272 (invoke "make" "install"))
8274 (define %standard-phases
8275 ;; The list of standard phases (quite a few are omitted
8276 ;; for brevity). Each element is a symbol/procedure pair.
8277 (list (cons 'unpack unpack)
8278 (cons 'configure configure)
8281 (cons 'install install)))
8284 This shows how @code{%standard-phases} is defined as a list of
8285 symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
8286 Manual}). The first pair associates the @code{unpack} procedure with
8287 the @code{unpack} symbol---a name; the second pair defines the
8288 @code{configure} phase similarly, and so on. When building a package
8289 that uses @code{gnu-build-system} with its default list of phases, those
8290 phases are executed sequentially. You can see the name of each phase
8291 started and completed in the build log of packages that you build.
8293 Let's now look at the procedures themselves. Each one is defined with
8294 @code{define*}: @code{#:key} lists keyword parameters the procedure
8295 accepts, possibly with a default value, and @code{#:allow-other-keys}
8296 specifies that other keyword parameters are ignored (@pxref{Optional
8297 Arguments,,, guile, GNU Guile Reference Manual}).
8299 The @code{unpack} procedure honors the @code{source} parameter, which
8300 the build system uses to pass the file name of the source tarball (or
8301 version control checkout), and it ignores other parameters. The
8302 @code{configure} phase only cares about the @code{outputs} parameter, an
8303 alist mapping package output names to their store file name
8304 (@pxref{Packages with Multiple Outputs}). It extracts the file name of
8305 for @code{out}, the default output, and passes it to
8306 @command{./configure} as the installation prefix, meaning that
8307 @command{make install} will eventually copy all the files in that
8308 directory (@pxref{Configuration, configuration and makefile
8309 conventions,, standards, GNU Coding Standards}). @code{build} and
8310 @code{install} ignore all their arguments. @code{check} honors the
8311 @code{test-target} argument, which specifies the name of the Makefile
8312 target to run tests; it prints a message and skips tests when
8313 @code{tests?} is false.
8315 @cindex build phases, customizing
8316 The list of phases used for a particular package can be changed with the
8317 @code{#:phases} parameter of the build system. Changing the set of
8318 build phases boils down to building a new alist of phases based on the
8319 @code{%standard-phases} alist described above. This can be done with
8320 standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
8321 Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
8322 more convenient to do so with @code{modify-phases} (@pxref{Build
8323 Utilities, @code{modify-phases}}).
8325 Here is an example of a package definition that removes the
8326 @code{configure} phase of @code{%standard-phases} and inserts a new
8327 phase before the @code{build} phase, called
8328 @code{set-prefix-in-makefile}:
8331 (define-public example
8334 ;; other fields omitted
8335 (build-system gnu-build-system)
8337 '(#:phases (modify-phases %standard-phases
8339 (add-before 'build 'set-prefix-in-makefile
8340 (lambda* (#:key outputs #:allow-other-keys)
8341 ;; Modify the makefile so that its
8342 ;; 'PREFIX' variable points to "out".
8343 (let ((out (assoc-ref outputs "out")))
8344 (substitute* "Makefile"
8346 (string-append "PREFIX = "
8351 The new phase that is inserted is written as an anonymous procedure,
8352 introduced with @code{lambda*}; it honors the @code{outputs} parameter
8353 we have seen before. @xref{Build Utilities}, for more about the helpers
8354 used by this phase, and for more examples of @code{modify-phases}.
8356 @cindex code staging
8357 @cindex staging, of code
8358 Keep in mind that build phases are code evaluated at the time the
8359 package is actually built. This explains why the whole
8360 @code{modify-phases} expression above is quoted (it comes after the
8361 @code{'} or apostrophe): it is @dfn{staged} for later execution.
8362 @xref{G-Expressions}, for an explanation of code staging and the
8363 @dfn{code strata} involved.
8365 @node Build Utilities
8366 @section Build Utilities
8368 As soon as you start writing non-trivial package definitions
8369 (@pxref{Defining Packages}) or other build actions
8370 (@pxref{G-Expressions}), you will likely start looking for helpers for
8371 ``shell-like'' actions---creating directories, copying and deleting
8372 files recursively, manipulating build phases, and so on. The
8373 @code{(guix build utils)} module provides such utility procedures.
8375 Most build systems load @code{(guix build utils)} (@pxref{Build
8376 Systems}). Thus, when writing custom build phases for your package
8377 definitions, you can usually assume those procedures are in scope.
8379 When writing G-expressions, you can import @code{(guix build utils)} on
8380 the ``build side'' using @code{with-imported-modules} and then put it in
8381 scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
8382 guile, GNU Guile Reference Manual}):
8385 (with-imported-modules '((guix build utils)) ;import it
8386 (computed-file "empty-tree"
8389 (use-modules (guix build utils))
8391 ;; Happily use its 'mkdir-p' procedure.
8392 (mkdir-p (string-append #$output "/a/b/c")))))
8395 The remainder of this section is the reference for most of the utility
8396 procedures provided by @code{(guix build utils)}.
8398 @c TODO Document what's missing.
8400 @subsection Dealing with Store File Names
8402 This section documents procedures that deal with store file names.
8404 @deffn {Scheme Procedure} %store-directory
8405 Return the directory name of the store.
8408 @deffn {Scheme Procedure} store-file-name? @var{file}
8409 Return true if @var{file} is in the store.
8412 @deffn {Scheme Procedure} strip-store-file-name @var{file}
8413 Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
8414 The result is typically a @code{"@var{package}-@var{version}"} string.
8417 @deffn {Scheme Procedure} package-name->name+version @var{name}
8418 Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
8419 values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
8420 unavailable, @var{name} and @code{#f} are returned. The first hyphen
8421 followed by a digit is considered to introduce the version part.
8424 @subsection File Types
8426 The procedures below deal with files and file types.
8428 @deffn {Scheme Procedure} directory-exists? @var{dir}
8429 Return @code{#t} if @var{dir} exists and is a directory.
8432 @deffn {Scheme Procedure} executable-file? @var{file}
8433 Return @code{#t} if @var{file} exists and is executable.
8436 @deffn {Scheme Procedure} symbolic-link? @var{file}
8437 Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
8440 @deffn {Scheme Procedure} elf-file? @var{file}
8441 @deffnx {Scheme Procedure} ar-file? @var{file}
8442 @deffnx {Scheme Procedure} gzip-file? @var{file}
8443 Return @code{#t} if @var{file} is, respectively, an ELF file, an
8444 @code{ar} archive (such as a @file{.a} static library), or a gzip file.
8447 @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
8448 If @var{file} is a gzip file, reset its embedded timestamp (as with
8449 @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
8450 When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
8453 @subsection File Manipulation
8455 The following procedures and macros help create, modify, and delete
8456 files. They provide functionality comparable to common shell utilities
8457 such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
8458 @command{sed}. They complement Guile's extensive, but low-level, file
8459 system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
8461 @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
8462 Run @var{body} with @var{directory} as the process's current directory.
8464 Essentially, this macro changes the current directory to @var{directory}
8465 before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
8466 guile, GNU Guile Reference Manual}). It changes back to the initial
8467 directory when the dynamic extent of @var{body} is left, be it @i{via}
8468 normal procedure return or @i{via} a non-local exit such as an
8472 @deffn {Scheme Procedure} mkdir-p @var{dir}
8473 Create directory @var{dir} and all its ancestors.
8476 @deffn {Scheme Procedure} install-file @var{file} @var{directory}
8477 Create @var{directory} if it does not exist and copy @var{file} in there
8478 under the same name.
8481 @deffn {Scheme Procedure} make-file-writable @var{file}
8482 Make @var{file} writable for its owner.
8485 @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
8486 [#:log (current-output-port)] [#:follow-symlinks? #f] [#:keep-mtime? #f]
8487 Copy @var{source} directory to @var{destination}. Follow symlinks if
8488 @var{follow-symlinks?} is true; otherwise, just preserve them. When
8489 @var{keep-mtime?} is true, keep the modification time of the files in
8490 @var{source} on those of @var{destination}. Write verbose output to the
8494 @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
8495 [#:follow-mounts? #f]
8496 Delete @var{dir} recursively, like @command{rm -rf}, without following
8497 symlinks. Don't follow mount points either, unless @var{follow-mounts?}
8498 is true. Report but ignore errors.
8501 @deffn {Scheme Syntax} substitute* @var{file} @
8502 ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
8503 Substitute @var{regexp} in @var{file} by the string returned by
8504 @var{body}. @var{body} is evaluated with each @var{match-var} bound to
8505 the corresponding positional regexp sub-expression. For example:
8511 (("foo([a-z]+)bar(.*)$" all letters end)
8512 (string-append "baz" letter end)))
8515 Here, anytime a line of @var{file} contains @code{hello}, it is replaced
8516 by @code{good morning}. Anytime a line of @var{file} matches the second
8517 regexp, @code{all} is bound to the complete match, @code{letters} is bound
8518 to the first sub-expression, and @code{end} is bound to the last one.
8520 When one of the @var{match-var} is @code{_}, no variable is bound to the
8521 corresponding match substring.
8523 Alternatively, @var{file} may be a list of file names, in which case
8524 they are all subject to the substitutions.
8526 Be careful about using @code{$} to match the end of a line; by itself it
8527 won't match the terminating newline of a line.
8530 @subsection File Search
8532 @cindex file, searching
8533 This section documents procedures to search and filter files.
8535 @deffn {Scheme Procedure} file-name-predicate @var{regexp}
8536 Return a predicate that returns true when passed a file name whose base
8537 name matches @var{regexp}.
8540 @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
8541 [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
8542 Return the lexicographically sorted list of files under @var{dir} for
8543 which @var{pred} returns true. @var{pred} is passed two arguments: the
8544 absolute file name, and its stat buffer; the default predicate always
8545 returns true. @var{pred} can also be a regular expression, in which
8546 case it is equivalent to @code{(file-name-predicate @var{pred})}.
8547 @var{stat} is used to obtain file information; using @code{lstat} means
8548 that symlinks are not followed. If @var{directories?} is true, then
8549 directories will also be included. If @var{fail-on-error?} is true,
8550 raise an exception upon error.
8553 Here are a few examples where we assume that the current directory is
8554 the root of the Guix source tree:
8557 ;; List all the regular files in the current directory.
8559 @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
8561 ;; List all the .scm files under gnu/services.
8562 (find-files "gnu/services" "\\.scm$")
8563 @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
8565 ;; List ar files in the current directory.
8566 (find-files "." (lambda (file stat) (ar-file? file)))
8567 @result{} ("./libformat.a" "./libstore.a" @dots{})
8570 @deffn {Scheme Procedure} which @var{program}
8571 Return the complete file name for @var{program} as found in
8572 @code{$PATH}, or @code{#f} if @var{program} could not be found.
8575 @subsection Build Phases
8577 @cindex build phases
8578 The @code{(guix build utils)} also contains tools to manipulate build
8579 phases as used by build systems (@pxref{Build Systems}). Build phases
8580 are represented as association lists or ``alists'' (@pxref{Association
8581 Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
8582 naming the phase and the associated value is a procedure (@pxref{Build
8585 Guile core and the @code{(srfi srfi-1)} module both provide tools to
8586 manipulate alists. The @code{(guix build utils)} module complements
8587 those with tools written with build phases in mind.
8589 @cindex build phases, modifying
8590 @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
8591 Modify @var{phases} sequentially as per each @var{clause}, which may
8592 have one of the following forms:
8595 (delete @var{old-phase-name})
8596 (replace @var{old-phase-name} @var{new-phase})
8597 (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
8598 (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
8601 Where every @var{phase-name} above is an expression evaluating to a
8602 symbol, and @var{new-phase} an expression evaluating to a procedure.
8605 The example below is taken from the definition of the @code{grep}
8606 package. It adds a phase to run after the @code{install} phase, called
8607 @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
8608 is for anonymous procedures) that takes a @code{#:outputs} keyword
8609 argument and ignores extra keyword arguments (@pxref{Optional
8610 Arguments,,, guile, GNU Guile Reference Manual}, for more on
8611 @code{lambda*} and optional and keyword arguments.) The phase uses
8612 @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
8613 scripts so that they refer to @code{grep} by its absolute file name:
8616 (modify-phases %standard-phases
8617 (add-after 'install 'fix-egrep-and-fgrep
8618 ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
8619 ;; absolute file name instead of searching for it in $PATH.
8620 (lambda* (#:key outputs #:allow-other-keys)
8621 (let* ((out (assoc-ref outputs "out"))
8622 (bin (string-append out "/bin")))
8623 (substitute* (list (string-append bin "/egrep")
8624 (string-append bin "/fgrep"))
8626 (string-append "exec " bin "/grep")))
8630 In the example below, phases are modified in two ways: the standard
8631 @code{configure} phase is deleted, presumably because the package does
8632 not have a @file{configure} script or anything similar, and the default
8633 @code{install} phase is replaced by one that manually copies the
8634 executable files to be installed:
8637 (modify-phases %standard-phases
8638 (delete 'configure) ;no 'configure' script
8640 (lambda* (#:key outputs #:allow-other-keys)
8641 ;; The package's Makefile doesn't provide an "install"
8642 ;; rule so do it by ourselves.
8643 (let ((bin (string-append (assoc-ref outputs "out")
8645 (install-file "footswitch" bin)
8646 (install-file "scythe" bin)
8650 @c TODO: Add more examples.
8659 Conceptually, the @dfn{store} is the place where derivations that have
8660 been built successfully are stored---by default, @file{/gnu/store}.
8661 Sub-directories in the store are referred to as @dfn{store items} or
8662 sometimes @dfn{store paths}. The store has an associated database that
8663 contains information such as the store paths referred to by each store
8664 path, and the list of @emph{valid} store items---results of successful
8665 builds. This database resides in @file{@var{localstatedir}/guix/db},
8666 where @var{localstatedir} is the state directory specified @i{via}
8667 @option{--localstatedir} at configure time, usually @file{/var}.
8669 The store is @emph{always} accessed by the daemon on behalf of its clients
8670 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
8671 connect to the daemon over a Unix-domain socket, send requests to it,
8672 and read the result---these are remote procedure calls, or RPCs.
8675 Users must @emph{never} modify files under @file{/gnu/store} directly.
8676 This would lead to inconsistencies and break the immutability
8677 assumptions of Guix's functional model (@pxref{Introduction}).
8679 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
8680 how to check the integrity of the store and attempt recovery from
8681 accidental modifications.
8684 The @code{(guix store)} module provides procedures to connect to the
8685 daemon, and to perform RPCs. These are described below. By default,
8686 @code{open-connection}, and thus all the @command{guix} commands,
8687 connect to the local daemon or to the URI specified by the
8688 @env{GUIX_DAEMON_SOCKET} environment variable.
8690 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
8691 When set, the value of this variable should be a file name or a URI
8692 designating the daemon endpoint. When it is a file name, it denotes a
8693 Unix-domain socket to connect to. In addition to file names, the
8694 supported URI schemes are:
8699 These are for Unix-domain sockets.
8700 @code{file:///var/guix/daemon-socket/socket} is equivalent to
8701 @file{/var/guix/daemon-socket/socket}.
8704 @cindex daemon, remote access
8705 @cindex remote access to the daemon
8706 @cindex daemon, cluster setup
8707 @cindex clusters, daemon setup
8708 These URIs denote connections over TCP/IP, without encryption nor
8709 authentication of the remote host. The URI must specify the host name
8710 and optionally a port number (by default port 44146 is used):
8713 guix://master.guix.example.org:1234
8716 This setup is suitable on local networks, such as clusters, where only
8717 trusted nodes may connect to the build daemon at
8718 @code{master.guix.example.org}.
8720 The @option{--listen} option of @command{guix-daemon} can be used to
8721 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
8722 @option{--listen}}).
8725 @cindex SSH access to build daemons
8726 These URIs allow you to connect to a remote daemon over SSH@. This
8727 feature requires Guile-SSH (@pxref{Requirements}) and a working
8728 @command{guile} binary in @env{PATH} on the destination machine. It
8729 supports public key and GSSAPI authentication. A typical URL might look
8733 ssh://charlie@@guix.example.org:22
8736 As for @command{guix copy}, the usual OpenSSH client configuration files
8737 are honored (@pxref{Invoking guix copy}).
8740 Additional URI schemes may be supported in the future.
8742 @c XXX: Remove this note when the protocol incurs fewer round trips
8743 @c and when (guix derivations) no longer relies on file system access.
8745 The ability to connect to remote build daemons is considered
8746 experimental as of @value{VERSION}. Please get in touch with us to
8747 share any problems or suggestions you may have (@pxref{Contributing}).
8751 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
8752 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
8753 @var{reserve-space?} is true, instruct it to reserve a little bit of
8754 extra space on the file system so that the garbage collector can still
8755 operate should the disk become full. Return a server object.
8757 @var{file} defaults to @code{%default-socket-path}, which is the normal
8758 location given the options that were passed to @command{configure}.
8761 @deffn {Scheme Procedure} close-connection @var{server}
8762 Close the connection to @var{server}.
8765 @defvr {Scheme Variable} current-build-output-port
8766 This variable is bound to a SRFI-39 parameter, which refers to the port
8767 where build and error logs sent by the daemon should be written.
8770 Procedures that make RPCs all take a server object as their first
8773 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
8774 @cindex invalid store items
8775 Return @code{#t} when @var{path} designates a valid store item and
8776 @code{#f} otherwise (an invalid item may exist on disk but still be
8777 invalid, for instance because it is the result of an aborted or failed
8780 A @code{&store-protocol-error} condition is raised if @var{path} is not
8781 prefixed by the store directory (@file{/gnu/store}).
8784 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
8785 Add @var{text} under file @var{name} in the store, and return its store
8786 path. @var{references} is the list of store paths referred to by the
8787 resulting store path.
8790 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
8792 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
8793 file names, or derivation/output pairs, using the specified
8794 @var{mode}---@code{(build-mode normal)} by default.
8797 Note that the @code{(guix monads)} module provides a monad as well as
8798 monadic versions of the above procedures, with the goal of making it
8799 more convenient to work with code that accesses the store (@pxref{The
8803 @i{This section is currently incomplete.}
8806 @section Derivations
8809 Low-level build actions and the environment in which they are performed
8810 are represented by @dfn{derivations}. A derivation contains the
8811 following pieces of information:
8815 The outputs of the derivation---derivations produce at least one file or
8816 directory in the store, but may produce more.
8819 @cindex build-time dependencies
8820 @cindex dependencies, build-time
8821 The inputs of the derivations---i.e., its build-time dependencies---which may
8822 be other derivations or plain files in the store (patches, build scripts,
8826 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
8829 The file name of a build script in the store, along with the arguments
8833 A list of environment variables to be defined.
8837 @cindex derivation path
8838 Derivations allow clients of the daemon to communicate build actions to
8839 the store. They exist in two forms: as an in-memory representation,
8840 both on the client- and daemon-side, and as files in the store whose
8841 name end in @file{.drv}---these files are referred to as @dfn{derivation
8842 paths}. Derivations paths can be passed to the @code{build-derivations}
8843 procedure to perform the build actions they prescribe (@pxref{The
8846 @cindex fixed-output derivations
8847 Operations such as file downloads and version-control checkouts for
8848 which the expected content hash is known in advance are modeled as
8849 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
8850 of a fixed-output derivation are independent of its inputs---e.g., a
8851 source code download produces the same result regardless of the download
8852 method and tools being used.
8855 @cindex run-time dependencies
8856 @cindex dependencies, run-time
8857 The outputs of derivations---i.e., the build results---have a set of
8858 @dfn{references}, as reported by the @code{references} RPC or the
8859 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
8860 are the set of run-time dependencies of the build results. References are a
8861 subset of the inputs of the derivation; this subset is automatically computed
8862 by the build daemon by scanning all the files in the outputs.
8864 The @code{(guix derivations)} module provides a representation of
8865 derivations as Scheme objects, along with procedures to create and
8866 otherwise manipulate derivations. The lowest-level primitive to create
8867 a derivation is the @code{derivation} procedure:
8869 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
8870 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
8871 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
8872 [#:system (%current-system)] [#:references-graphs #f] @
8873 [#:allowed-references #f] [#:disallowed-references #f] @
8874 [#:leaked-env-vars #f] [#:local-build? #f] @
8875 [#:substitutable? #t] [#:properties '()]
8876 Build a derivation with the given arguments, and return the resulting
8877 @code{<derivation>} object.
8879 When @var{hash} and @var{hash-algo} are given, a
8880 @dfn{fixed-output derivation} is created---i.e., one whose result is
8881 known in advance, such as a file download. If, in addition,
8882 @var{recursive?} is true, then that fixed output may be an executable
8883 file or a directory and @var{hash} must be the hash of an archive
8884 containing this output.
8886 When @var{references-graphs} is true, it must be a list of file
8887 name/store path pairs. In that case, the reference graph of each store
8888 path is exported in the build environment in the corresponding file, in
8889 a simple text format.
8891 When @var{allowed-references} is true, it must be a list of store items
8892 or outputs that the derivation's output may refer to. Likewise,
8893 @var{disallowed-references}, if true, must be a list of things the
8894 outputs may @emph{not} refer to.
8896 When @var{leaked-env-vars} is true, it must be a list of strings
8897 denoting environment variables that are allowed to ``leak'' from the
8898 daemon's environment to the build environment. This is only applicable
8899 to fixed-output derivations---i.e., when @var{hash} is true. The main
8900 use is to allow variables such as @code{http_proxy} to be passed to
8901 derivations that download files.
8903 When @var{local-build?} is true, declare that the derivation is not a
8904 good candidate for offloading and should rather be built locally
8905 (@pxref{Daemon Offload Setup}). This is the case for small derivations
8906 where the costs of data transfers would outweigh the benefits.
8908 When @var{substitutable?} is false, declare that substitutes of the
8909 derivation's output should not be used (@pxref{Substitutes}). This is
8910 useful, for instance, when building packages that capture details of the
8911 host CPU instruction set.
8913 @var{properties} must be an association list describing ``properties'' of the
8914 derivation. It is kept as-is, uninterpreted, in the derivation.
8918 Here's an example with a shell script as its builder, assuming
8919 @var{store} is an open connection to the daemon, and @var{bash} points
8920 to a Bash executable in the store:
8923 (use-modules (guix utils)
8927 (let ((builder ; add the Bash script to the store
8928 (add-text-to-store store "my-builder.sh"
8929 "echo hello world > $out\n" '())))
8930 (derivation store "foo"
8931 bash `("-e" ,builder)
8932 #:inputs `((,bash) (,builder))
8933 #:env-vars '(("HOME" . "/homeless"))))
8934 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
8937 As can be guessed, this primitive is cumbersome to use directly. A
8938 better approach is to write build scripts in Scheme, of course! The
8939 best course of action for that is to write the build code as a
8940 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
8941 information, @pxref{G-Expressions}.
8943 Once upon a time, @code{gexp->derivation} did not exist and constructing
8944 derivations with build code written in Scheme was achieved with
8945 @code{build-expression->derivation}, documented below. This procedure
8946 is now deprecated in favor of the much nicer @code{gexp->derivation}.
8948 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
8949 @var{name} @var{exp} @
8950 [#:system (%current-system)] [#:inputs '()] @
8951 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
8952 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
8953 [#:references-graphs #f] [#:allowed-references #f] @
8954 [#:disallowed-references #f] @
8955 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
8956 Return a derivation that executes Scheme expression @var{exp} as a
8957 builder for derivation @var{name}. @var{inputs} must be a list of
8958 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
8959 @code{"out"} is assumed. @var{modules} is a list of names of Guile
8960 modules from the current search path to be copied in the store,
8961 compiled, and made available in the load path during the execution of
8962 @var{exp}---e.g., @code{((guix build utils) (guix build
8963 gnu-build-system))}.
8965 @var{exp} is evaluated in an environment where @code{%outputs} is bound
8966 to a list of output/path pairs, and where @code{%build-inputs} is bound
8967 to a list of string/output-path pairs made from @var{inputs}.
8968 Optionally, @var{env-vars} is a list of string pairs specifying the name
8969 and value of environment variables visible to the builder. The builder
8970 terminates by passing the result of @var{exp} to @code{exit}; thus, when
8971 @var{exp} returns @code{#f}, the build is considered to have failed.
8973 @var{exp} is built using @var{guile-for-build} (a derivation). When
8974 @var{guile-for-build} is omitted or is @code{#f}, the value of the
8975 @code{%guile-for-build} fluid is used instead.
8977 See the @code{derivation} procedure for the meaning of
8978 @var{references-graphs}, @var{allowed-references},
8979 @var{disallowed-references}, @var{local-build?}, and
8980 @var{substitutable?}.
8984 Here's an example of a single-output derivation that creates a directory
8985 containing one file:
8988 (let ((builder '(let ((out (assoc-ref %outputs "out")))
8989 (mkdir out) ; create /gnu/store/@dots{}-goo
8990 (call-with-output-file (string-append out "/test")
8992 (display '(hello guix) p))))))
8993 (build-expression->derivation store "goo" builder))
8995 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
8999 @node The Store Monad
9000 @section The Store Monad
9004 The procedures that operate on the store described in the previous
9005 sections all take an open connection to the build daemon as their first
9006 argument. Although the underlying model is functional, they either have
9007 side effects or depend on the current state of the store.
9009 The former is inconvenient: the connection to the build daemon has to be
9010 carried around in all those functions, making it impossible to compose
9011 functions that do not take that parameter with functions that do. The
9012 latter can be problematic: since store operations have side effects
9013 and/or depend on external state, they have to be properly sequenced.
9015 @cindex monadic values
9016 @cindex monadic functions
9017 This is where the @code{(guix monads)} module comes in. This module
9018 provides a framework for working with @dfn{monads}, and a particularly
9019 useful monad for our uses, the @dfn{store monad}. Monads are a
9020 construct that allows two things: associating ``context'' with values
9021 (in our case, the context is the store), and building sequences of
9022 computations (here computations include accesses to the store). Values
9023 in a monad---values that carry this additional context---are called
9024 @dfn{monadic values}; procedures that return such values are called
9025 @dfn{monadic procedures}.
9027 Consider this ``normal'' procedure:
9030 (define (sh-symlink store)
9031 ;; Return a derivation that symlinks the 'bash' executable.
9032 (let* ((drv (package-derivation store bash))
9033 (out (derivation->output-path drv))
9034 (sh (string-append out "/bin/bash")))
9035 (build-expression->derivation store "sh"
9036 `(symlink ,sh %output))))
9039 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
9040 as a monadic function:
9043 (define (sh-symlink)
9044 ;; Same, but return a monadic value.
9045 (mlet %store-monad ((drv (package->derivation bash)))
9046 (gexp->derivation "sh"
9047 #~(symlink (string-append #$drv "/bin/bash")
9051 There are several things to note in the second version: the @code{store}
9052 parameter is now implicit and is ``threaded'' in the calls to the
9053 @code{package->derivation} and @code{gexp->derivation} monadic
9054 procedures, and the monadic value returned by @code{package->derivation}
9055 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
9057 As it turns out, the call to @code{package->derivation} can even be
9058 omitted since it will take place implicitly, as we will see later
9059 (@pxref{G-Expressions}):
9062 (define (sh-symlink)
9063 (gexp->derivation "sh"
9064 #~(symlink (string-append #$bash "/bin/bash")
9069 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
9070 @c for the funny quote.
9071 Calling the monadic @code{sh-symlink} has no effect. As someone once
9072 said, ``you exit a monad like you exit a building on fire: by running''.
9073 So, to exit the monad and get the desired effect, one must use
9074 @code{run-with-store}:
9077 (run-with-store (open-connection) (sh-symlink))
9078 @result{} /gnu/store/...-sh-symlink
9081 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
9082 new ``meta-commands'' to make it easier to deal with monadic procedures:
9083 @code{run-in-store}, and @code{enter-store-monad}. The former is used
9084 to ``run'' a single monadic value through the store:
9087 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
9088 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
9091 The latter enters a recursive REPL, where all the return values are
9092 automatically run through the store:
9095 scheme@@(guile-user)> ,enter-store-monad
9096 store-monad@@(guile-user) [1]> (package->derivation hello)
9097 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
9098 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
9099 $3 = "/gnu/store/@dots{}-foo"
9100 store-monad@@(guile-user) [1]> ,q
9101 scheme@@(guile-user)>
9105 Note that non-monadic values cannot be returned in the
9106 @code{store-monad} REPL.
9108 The main syntactic forms to deal with monads in general are provided by
9109 the @code{(guix monads)} module and are described below.
9111 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
9112 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
9116 @deffn {Scheme Syntax} return @var{val}
9117 Return a monadic value that encapsulates @var{val}.
9120 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
9121 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
9122 procedures @var{mproc}@dots{}@footnote{This operation is commonly
9123 referred to as ``bind'', but that name denotes an unrelated procedure in
9124 Guile. Thus we use this somewhat cryptic symbol inherited from the
9125 Haskell language.}. There can be one @var{mproc} or several of them, as
9130 (with-monad %state-monad
9132 (lambda (x) (return (+ 1 x)))
9133 (lambda (x) (return (* 2 x)))))
9137 @result{} some-state
9141 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
9143 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
9145 Bind the variables @var{var} to the monadic values @var{mval} in
9146 @var{body}, which is a sequence of expressions. As with the bind
9147 operator, this can be thought of as ``unpacking'' the raw, non-monadic
9148 value ``contained'' in @var{mval} and making @var{var} refer to that
9149 raw, non-monadic value within the scope of the @var{body}. The form
9150 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
9151 @var{val}, as per @code{let}. The binding operations occur in sequence
9152 from left to right. The last expression of @var{body} must be a monadic
9153 expression, and its result will become the result of the @code{mlet} or
9154 @code{mlet*} when run in the @var{monad}.
9156 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
9157 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
9160 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
9161 Bind @var{mexp} and the following monadic expressions in sequence,
9162 returning the result of the last expression. Every expression in the
9163 sequence must be a monadic expression.
9165 This is akin to @code{mlet}, except that the return values of the
9166 monadic expressions are ignored. In that sense, it is analogous to
9167 @code{begin}, but applied to monadic expressions.
9170 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
9171 When @var{condition} is true, evaluate the sequence of monadic
9172 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
9173 @var{condition} is false, return @code{*unspecified*} in the current
9174 monad. Every expression in the sequence must be a monadic expression.
9177 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
9178 When @var{condition} is false, evaluate the sequence of monadic
9179 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
9180 @var{condition} is true, return @code{*unspecified*} in the current
9181 monad. Every expression in the sequence must be a monadic expression.
9185 The @code{(guix monads)} module provides the @dfn{state monad}, which
9186 allows an additional value---the state---to be @emph{threaded} through
9187 monadic procedure calls.
9189 @defvr {Scheme Variable} %state-monad
9190 The state monad. Procedures in the state monad can access and change
9191 the state that is threaded.
9193 Consider the example below. The @code{square} procedure returns a value
9194 in the state monad. It returns the square of its argument, but also
9195 increments the current state value:
9199 (mlet %state-monad ((count (current-state)))
9200 (mbegin %state-monad
9201 (set-current-state (+ 1 count))
9204 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
9209 When ``run'' through @code{%state-monad}, we obtain that additional state
9210 value, which is the number of @code{square} calls.
9213 @deffn {Monadic Procedure} current-state
9214 Return the current state as a monadic value.
9217 @deffn {Monadic Procedure} set-current-state @var{value}
9218 Set the current state to @var{value} and return the previous state as a
9222 @deffn {Monadic Procedure} state-push @var{value}
9223 Push @var{value} to the current state, which is assumed to be a list,
9224 and return the previous state as a monadic value.
9227 @deffn {Monadic Procedure} state-pop
9228 Pop a value from the current state and return it as a monadic value.
9229 The state is assumed to be a list.
9232 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
9233 Run monadic value @var{mval} starting with @var{state} as the initial
9234 state. Return two values: the resulting value, and the resulting state.
9237 The main interface to the store monad, provided by the @code{(guix
9238 store)} module, is as follows.
9240 @defvr {Scheme Variable} %store-monad
9241 The store monad---an alias for @code{%state-monad}.
9243 Values in the store monad encapsulate accesses to the store. When its
9244 effect is needed, a value of the store monad must be ``evaluated'' by
9245 passing it to the @code{run-with-store} procedure (see below).
9248 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
9249 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
9250 open store connection.
9253 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
9254 Return as a monadic value the absolute file name in the store of the file
9255 containing @var{text}, a string. @var{references} is a list of store items that the
9256 resulting text file refers to; it defaults to the empty list.
9259 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
9260 Return as a monadic value the absolute file name in the store of the file
9261 containing @var{data}, a bytevector. @var{references} is a list of store
9262 items that the resulting binary file refers to; it defaults to the empty list.
9265 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
9266 [#:recursive? #t] [#:select? (const #t)]
9267 Return the name of @var{file} once interned in the store. Use
9268 @var{name} as its store name, or the basename of @var{file} if
9269 @var{name} is omitted.
9271 When @var{recursive?} is true, the contents of @var{file} are added
9272 recursively; if @var{file} designates a flat file and @var{recursive?}
9273 is true, its contents are added, and its permission bits are kept.
9275 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
9276 @var{stat})} for each directory entry, where @var{file} is the entry's
9277 absolute file name and @var{stat} is the result of @code{lstat}; exclude
9278 entries for which @var{select?} does not return true.
9280 The example below adds a file to the store, under two different names:
9283 (run-with-store (open-connection)
9284 (mlet %store-monad ((a (interned-file "README"))
9285 (b (interned-file "README" "LEGU-MIN")))
9286 (return (list a b))))
9288 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
9293 The @code{(guix packages)} module exports the following package-related
9296 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
9297 [#:system (%current-system)] [#:target #f] @
9300 value in the absolute file name of @var{file} within the @var{output}
9301 directory of @var{package}. When @var{file} is omitted, return the name
9302 of the @var{output} directory of @var{package}. When @var{target} is
9303 true, use it as a cross-compilation target triplet.
9305 Note that this procedure does @emph{not} build @var{package}. Thus, the
9306 result might or might not designate an existing file. We recommend not
9307 using this procedure unless you know what you are doing.
9310 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
9311 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
9312 @var{target} [@var{system}]
9313 Monadic version of @code{package-derivation} and
9314 @code{package-cross-derivation} (@pxref{Defining Packages}).
9319 @section G-Expressions
9321 @cindex G-expression
9322 @cindex build code quoting
9323 So we have ``derivations'', which represent a sequence of build actions
9324 to be performed to produce an item in the store (@pxref{Derivations}).
9325 These build actions are performed when asking the daemon to actually
9326 build the derivations; they are run by the daemon in a container
9327 (@pxref{Invoking guix-daemon}).
9329 @cindex code staging
9330 @cindex staging, of code
9331 @cindex strata of code
9332 It should come as no surprise that we like to write these build actions
9333 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
9334 code@footnote{The term @dfn{stratum} in this context was coined by
9335 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
9336 Kiselyov, who has written insightful
9337 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
9338 on this topic}, refers to this kind of code generation as
9339 @dfn{staging}.}: the ``host code''---code that defines packages, talks
9340 to the daemon, etc.---and the ``build code''---code that actually
9341 performs build actions, such as making directories, invoking
9342 @command{make}, and so on (@pxref{Build Phases}).
9344 To describe a derivation and its build actions, one typically needs to
9345 embed build code inside host code. It boils down to manipulating build
9346 code as data, and the homoiconicity of Scheme---code has a direct
9347 representation as data---comes in handy for that. But we need more than
9348 the normal @code{quasiquote} mechanism in Scheme to construct build
9351 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
9352 S-expressions adapted to build expressions. G-expressions, or
9353 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
9354 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
9355 @code{#$}, and @code{#$@@}), which are comparable to
9356 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
9357 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
9358 GNU Guile Reference Manual}). However, there are major differences:
9362 Gexps are meant to be written to a file and run or manipulated by other
9366 When a high-level object such as a package or derivation is unquoted
9367 inside a gexp, the result is as if its output file name had been
9371 Gexps carry information about the packages or derivations they refer to,
9372 and these dependencies are automatically added as inputs to the build
9373 processes that use them.
9376 @cindex lowering, of high-level objects in gexps
9377 This mechanism is not limited to package and derivation
9378 objects: @dfn{compilers} able to ``lower'' other high-level objects to
9379 derivations or files in the store can be defined,
9380 such that these objects can also be inserted
9381 into gexps. For example, a useful type of high-level objects that can be
9382 inserted in a gexp is ``file-like objects'', which make it easy to
9383 add files to the store and to refer to them in
9384 derivations and such (see @code{local-file} and @code{plain-file}
9387 To illustrate the idea, here is an example of a gexp:
9394 (symlink (string-append #$coreutils "/bin/ls")
9398 This gexp can be passed to @code{gexp->derivation}; we obtain a
9399 derivation that builds a directory containing exactly one symlink to
9400 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
9403 (gexp->derivation "the-thing" build-exp)
9406 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
9407 substituted to the reference to the @var{coreutils} package in the
9408 actual build code, and @var{coreutils} is automatically made an input to
9409 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
9410 output)}) is replaced by a string containing the directory name of the
9411 output of the derivation.
9413 @cindex cross compilation
9414 In a cross-compilation context, it is useful to distinguish between
9415 references to the @emph{native} build of a package---that can run on the
9416 host---versus references to cross builds of a package. To that end, the
9417 @code{#+} plays the same role as @code{#$}, but is a reference to a
9418 native package build:
9421 (gexp->derivation "vi"
9424 (mkdir (string-append #$output "/bin"))
9425 (system* (string-append #+coreutils "/bin/ln")
9427 (string-append #$emacs "/bin/emacs")
9428 (string-append #$output "/bin/vi")))
9429 #:target "aarch64-linux-gnu")
9433 In the example above, the native build of @var{coreutils} is used, so
9434 that @command{ln} can actually run on the host; but then the
9435 cross-compiled build of @var{emacs} is referenced.
9437 @cindex imported modules, for gexps
9438 @findex with-imported-modules
9439 Another gexp feature is @dfn{imported modules}: sometimes you want to be
9440 able to use certain Guile modules from the ``host environment'' in the
9441 gexp, so those modules should be imported in the ``build environment''.
9442 The @code{with-imported-modules} form allows you to express that:
9445 (let ((build (with-imported-modules '((guix build utils))
9447 (use-modules (guix build utils))
9448 (mkdir-p (string-append #$output "/bin"))))))
9449 (gexp->derivation "empty-dir"
9452 (display "success!\n")
9457 In this example, the @code{(guix build utils)} module is automatically
9458 pulled into the isolated build environment of our gexp, such that
9459 @code{(use-modules (guix build utils))} works as expected.
9461 @cindex module closure
9462 @findex source-module-closure
9463 Usually you want the @emph{closure} of the module to be imported---i.e.,
9464 the module itself and all the modules it depends on---rather than just
9465 the module; failing to do that, attempts to use the module will fail
9466 because of missing dependent modules. The @code{source-module-closure}
9467 procedure computes the closure of a module by looking at its source file
9468 headers, which comes in handy in this case:
9471 (use-modules (guix modules)) ;for 'source-module-closure'
9473 (with-imported-modules (source-module-closure
9474 '((guix build utils)
9476 (gexp->derivation "something-with-vms"
9478 (use-modules (guix build utils)
9483 @cindex extensions, for gexps
9484 @findex with-extensions
9485 In the same vein, sometimes you want to import not just pure-Scheme
9486 modules, but also ``extensions'' such as Guile bindings to C libraries
9487 or other ``full-blown'' packages. Say you need the @code{guile-json}
9488 package available on the build side, here's how you would do it:
9491 (use-modules (gnu packages guile)) ;for 'guile-json'
9493 (with-extensions (list guile-json)
9494 (gexp->derivation "something-with-json"
9496 (use-modules (json))
9500 The syntactic form to construct gexps is summarized below.
9502 @deffn {Scheme Syntax} #~@var{exp}
9503 @deffnx {Scheme Syntax} (gexp @var{exp})
9504 Return a G-expression containing @var{exp}. @var{exp} may contain one
9505 or more of the following forms:
9509 @itemx (ungexp @var{obj})
9510 Introduce a reference to @var{obj}. @var{obj} may have one of the
9511 supported types, for example a package or a
9512 derivation, in which case the @code{ungexp} form is replaced by its
9513 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
9515 If @var{obj} is a list, it is traversed and references to supported
9516 objects are substituted similarly.
9518 If @var{obj} is another gexp, its contents are inserted and its
9519 dependencies are added to those of the containing gexp.
9521 If @var{obj} is another kind of object, it is inserted as is.
9523 @item #$@var{obj}:@var{output}
9524 @itemx (ungexp @var{obj} @var{output})
9525 This is like the form above, but referring explicitly to the
9526 @var{output} of @var{obj}---this is useful when @var{obj} produces
9527 multiple outputs (@pxref{Packages with Multiple Outputs}).
9530 @itemx #+@var{obj}:output
9531 @itemx (ungexp-native @var{obj})
9532 @itemx (ungexp-native @var{obj} @var{output})
9533 Same as @code{ungexp}, but produces a reference to the @emph{native}
9534 build of @var{obj} when used in a cross compilation context.
9536 @item #$output[:@var{output}]
9537 @itemx (ungexp output [@var{output}])
9538 Insert a reference to derivation output @var{output}, or to the main
9539 output when @var{output} is omitted.
9541 This only makes sense for gexps passed to @code{gexp->derivation}.
9544 @itemx (ungexp-splicing @var{lst})
9545 Like the above, but splices the contents of @var{lst} inside the
9549 @itemx (ungexp-native-splicing @var{lst})
9550 Like the above, but refers to native builds of the objects listed in
9555 G-expressions created by @code{gexp} or @code{#~} are run-time objects
9556 of the @code{gexp?} type (see below).
9559 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
9560 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
9561 in their execution environment.
9563 Each item in @var{modules} can be the name of a module, such as
9564 @code{(guix build utils)}, or it can be a module name, followed by an
9565 arrow, followed by a file-like object:
9568 `((guix build utils)
9570 ((guix config) => ,(scheme-file "config.scm"
9571 #~(define-module @dots{}))))
9575 In the example above, the first two modules are taken from the search
9576 path, and the last one is created from the given file-like object.
9578 This form has @emph{lexical} scope: it has an effect on the gexps
9579 directly defined in @var{body}@dots{}, but not on those defined, say, in
9580 procedures called from @var{body}@dots{}.
9583 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
9584 Mark the gexps defined in @var{body}@dots{} as requiring
9585 @var{extensions} in their build and execution environment.
9586 @var{extensions} is typically a list of package objects such as those
9587 defined in the @code{(gnu packages guile)} module.
9589 Concretely, the packages listed in @var{extensions} are added to the
9590 load path while compiling imported modules in @var{body}@dots{}; they
9591 are also added to the load path of the gexp returned by
9595 @deffn {Scheme Procedure} gexp? @var{obj}
9596 Return @code{#t} if @var{obj} is a G-expression.
9599 G-expressions are meant to be written to disk, either as code building
9600 some derivation, or as plain files in the store. The monadic procedures
9601 below allow you to do that (@pxref{The Store Monad}, for more
9602 information about monads).
9604 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
9605 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
9606 [#:hash #f] [#:hash-algo #f] @
9607 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
9608 [#:module-path @code{%load-path}] @
9609 [#:effective-version "2.2"] @
9610 [#:references-graphs #f] [#:allowed-references #f] @
9611 [#:disallowed-references #f] @
9612 [#:leaked-env-vars #f] @
9613 [#:script-name (string-append @var{name} "-builder")] @
9614 [#:deprecation-warnings #f] @
9615 [#:local-build? #f] [#:substitutable? #t] @
9616 [#:properties '()] [#:guile-for-build #f]
9617 Return a derivation @var{name} that runs @var{exp} (a gexp) with
9618 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
9619 stored in a file called @var{script-name}. When @var{target} is true,
9620 it is used as the cross-compilation target triplet for packages referred
9623 @var{modules} is deprecated in favor of @code{with-imported-modules}.
9625 make @var{modules} available in the evaluation context of @var{exp};
9626 @var{modules} is a list of names of Guile modules searched in
9627 @var{module-path} to be copied in the store, compiled, and made available in
9628 the load path during the execution of @var{exp}---e.g., @code{((guix
9629 build utils) (guix build gnu-build-system))}.
9631 @var{effective-version} determines the string to use when adding extensions of
9632 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
9634 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
9637 When @var{references-graphs} is true, it must be a list of tuples of one of the
9641 (@var{file-name} @var{package})
9642 (@var{file-name} @var{package} @var{output})
9643 (@var{file-name} @var{derivation})
9644 (@var{file-name} @var{derivation} @var{output})
9645 (@var{file-name} @var{store-item})
9648 The right-hand-side of each element of @var{references-graphs} is automatically made
9649 an input of the build process of @var{exp}. In the build environment, each
9650 @var{file-name} contains the reference graph of the corresponding item, in a simple
9653 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
9654 In the latter case, the list denotes store items that the result is allowed to
9655 refer to. Any reference to another store item will lead to a build error.
9656 Similarly for @var{disallowed-references}, which can list items that must not be
9657 referenced by the outputs.
9659 @var{deprecation-warnings} determines whether to show deprecation warnings while
9660 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
9662 The other arguments are as for @code{derivation} (@pxref{Derivations}).
9665 @cindex file-like objects
9666 The @code{local-file}, @code{plain-file}, @code{computed-file},
9667 @code{program-file}, and @code{scheme-file} procedures below return
9668 @dfn{file-like objects}. That is, when unquoted in a G-expression,
9669 these objects lead to a file in the store. Consider this G-expression:
9672 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
9673 #$(local-file "/tmp/my-nscd.conf"))
9676 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
9677 to the store. Once expanded, for instance @i{via}
9678 @code{gexp->derivation}, the G-expression refers to that copy under
9679 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
9680 does not have any effect on what the G-expression does.
9681 @code{plain-file} can be used similarly; it differs in that the file
9682 content is directly passed as a string.
9684 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
9685 [#:recursive? #f] [#:select? (const #t)]
9686 Return an object representing local file @var{file} to add to the store;
9687 this object can be used in a gexp. If @var{file} is a literal string
9688 denoting a relative file name, it is looked up relative to the source
9689 file where it appears; if @var{file} is not a literal string, it is
9690 looked up relative to the current working directory at run time.
9691 @var{file} will be added to the store under @var{name}--by default the
9692 base name of @var{file}.
9694 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
9695 designates a flat file and @var{recursive?} is true, its contents are added, and its
9696 permission bits are kept.
9698 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
9699 @var{stat})} for each directory entry, where @var{file} is the entry's
9700 absolute file name and @var{stat} is the result of @code{lstat}; exclude
9701 entries for which @var{select?} does not return true.
9703 This is the declarative counterpart of the @code{interned-file} monadic
9704 procedure (@pxref{The Store Monad, @code{interned-file}}).
9707 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
9708 Return an object representing a text file called @var{name} with the given
9709 @var{content} (a string or a bytevector) to be added to the store.
9711 This is the declarative counterpart of @code{text-file}.
9714 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
9717 Return an object representing the store item @var{name}, a file or
9718 directory computed by @var{gexp}. When @var{local-build?} is true (the
9719 default), the derivation is built locally. @var{options} is a list of
9720 additional arguments to pass to @code{gexp->derivation}.
9722 This is the declarative counterpart of @code{gexp->derivation}.
9725 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
9726 [#:guile (default-guile)] [#:module-path %load-path] @
9727 [#:system (%current-system)] [#:target #f]
9728 Return an executable script @var{name} that runs @var{exp} using
9729 @var{guile}, with @var{exp}'s imported modules in its search path.
9730 Look up @var{exp}'s modules in @var{module-path}.
9732 The example below builds a script that simply invokes the @command{ls}
9736 (use-modules (guix gexp) (gnu packages base))
9738 (gexp->script "list-files"
9739 #~(execl #$(file-append coreutils "/bin/ls")
9743 When ``running'' it through the store (@pxref{The Store Monad,
9744 @code{run-with-store}}), we obtain a derivation that produces an
9745 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
9748 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
9750 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
9754 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
9755 [#:guile #f] [#:module-path %load-path]
9756 Return an object representing the executable store item @var{name} that
9757 runs @var{gexp}. @var{guile} is the Guile package used to execute that
9758 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
9760 This is the declarative counterpart of @code{gexp->script}.
9763 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
9764 [#:set-load-path? #t] [#:module-path %load-path] @
9766 [#:guile (default-guile)]
9767 Return a derivation that builds a file @var{name} containing @var{exp}.
9768 When @var{splice?} is true, @var{exp} is considered to be a list of
9769 expressions that will be spliced in the resulting file.
9771 When @var{set-load-path?} is true, emit code in the resulting file to
9772 set @code{%load-path} and @code{%load-compiled-path} to honor
9773 @var{exp}'s imported modules. Look up @var{exp}'s modules in
9776 The resulting file holds references to all the dependencies of @var{exp}
9777 or a subset thereof.
9780 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
9781 [#:splice? #f] [#:set-load-path? #t]
9782 Return an object representing the Scheme file @var{name} that contains
9785 This is the declarative counterpart of @code{gexp->file}.
9788 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
9789 Return as a monadic value a derivation that builds a text file
9790 containing all of @var{text}. @var{text} may list, in addition to
9791 strings, objects of any type that can be used in a gexp: packages,
9792 derivations, local file objects, etc. The resulting store file holds
9793 references to all these.
9795 This variant should be preferred over @code{text-file} anytime the file
9796 to create will reference items from the store. This is typically the
9797 case when building a configuration file that embeds store file names,
9801 (define (profile.sh)
9802 ;; Return the name of a shell script in the store that
9803 ;; initializes the 'PATH' environment variable.
9804 (text-file* "profile.sh"
9805 "export PATH=" coreutils "/bin:"
9806 grep "/bin:" sed "/bin\n"))
9809 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
9810 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
9811 preventing them from being garbage-collected during its lifetime.
9814 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
9815 Return an object representing store file @var{name} containing
9816 @var{text}. @var{text} is a sequence of strings and file-like objects,
9820 (mixed-text-file "profile"
9821 "export PATH=" coreutils "/bin:" grep "/bin")
9824 This is the declarative counterpart of @code{text-file*}.
9827 @deffn {Scheme Procedure} file-union @var{name} @var{files}
9828 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
9829 Each item in @var{files} must be a two-element list where the first element is the
9830 file name to use in the new directory, and the second element is a gexp
9831 denoting the target file. Here's an example:
9835 `(("hosts" ,(plain-file "hosts"
9836 "127.0.0.1 localhost"))
9837 ("bashrc" ,(plain-file "bashrc"
9838 "alias ls='ls --color=auto'"))))
9841 This yields an @code{etc} directory containing these two files.
9844 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
9845 Return a directory that is the union of @var{things}, where @var{things} is a list of
9846 file-like objects denoting directories. For example:
9849 (directory-union "guile+emacs" (list guile emacs))
9852 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
9855 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
9856 Return a file-like object that expands to the concatenation of @var{obj}
9857 and @var{suffix}, where @var{obj} is a lowerable object and each
9858 @var{suffix} is a string.
9860 As an example, consider this gexp:
9863 (gexp->script "run-uname"
9864 #~(system* #$(file-append coreutils
9868 The same effect could be achieved with:
9871 (gexp->script "run-uname"
9872 #~(system* (string-append #$coreutils
9876 There is one difference though: in the @code{file-append} case, the
9877 resulting script contains the absolute file name as a string, whereas in
9878 the second case, the resulting script contains a @code{(string-append
9879 @dots{})} expression to construct the file name @emph{at run time}.
9882 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
9883 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
9884 Bind @var{system} to the currently targeted system---e.g.,
9885 @code{"x86_64-linux"}---within @var{body}.
9887 In the second case, additionally bind @var{target} to the current
9888 cross-compilation target---a GNU triplet such as
9889 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
9892 @code{let-system} is useful in the occasional case where the object
9893 spliced into the gexp depends on the target system, as in this example:
9897 #+(let-system system
9898 (cond ((string-prefix? "armhf-" system)
9899 (file-append qemu "/bin/qemu-system-arm"))
9900 ((string-prefix? "x86_64-" system)
9901 (file-append qemu "/bin/qemu-system-x86_64"))
9904 "-net" "user" #$image)
9908 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
9909 This macro is similar to the @code{parameterize} form for
9910 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
9911 Guile Reference Manual}). The key difference is that it takes effect
9912 when the file-like object returned by @var{exp} is lowered to a
9913 derivation or store item.
9915 A typical use of @code{with-parameters} is to force the system in effect
9919 (with-parameters ((%current-system "i686-linux"))
9923 The example above returns an object that corresponds to the i686 build
9924 of Coreutils, regardless of the current value of @code{%current-system}.
9928 Of course, in addition to gexps embedded in ``host'' code, there are
9929 also modules containing build tools. To make it clear that they are
9930 meant to be used in the build stratum, these modules are kept in the
9931 @code{(guix build @dots{})} name space.
9933 @cindex lowering, of high-level objects in gexps
9934 Internally, high-level objects are @dfn{lowered}, using their compiler,
9935 to either derivations or store items. For instance, lowering a package
9936 yields a derivation, and lowering a @code{plain-file} yields a store
9937 item. This is achieved using the @code{lower-object} monadic procedure.
9939 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
9941 Return as a value in @code{%store-monad} the derivation or store item
9942 corresponding to @var{obj} for @var{system}, cross-compiling for
9943 @var{target} if @var{target} is true. @var{obj} must be an object that
9944 has an associated gexp compiler, such as a @code{<package>}.
9947 @node Invoking guix repl
9948 @section Invoking @command{guix repl}
9950 @cindex REPL, read-eval-print loop, script
9951 The @command{guix repl} command makes it easier to program Guix in Guile
9952 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
9953 programming (@pxref{Using Guile Interactively,,, guile,
9954 GNU Guile Reference Manual}), or by running Guile scripts
9955 (@pxref{Running Guile Scripts,,, guile,
9956 GNU Guile Reference Manual}).
9957 Compared to just launching the @command{guile}
9958 command, @command{guix repl} guarantees that all the Guix modules and all its
9959 dependencies are available in the search path.
9961 The general syntax is:
9964 guix repl @var{options} [@var{file} @var{args}]
9967 When a @var{file} argument is provided, @var{file} is
9968 executed as a Guile scripts:
9971 guix repl my-script.scm
9974 To pass arguments to the script, use @code{--} to prevent them from
9975 being interpreted as arguments to @command{guix repl} itself:
9978 guix repl -- my-script.scm --input=foo.txt
9981 To make a script executable directly from the shell, using the guix
9982 executable that is on the user's search path, add the following two
9983 lines at the top of the script:
9986 @code{#!/usr/bin/env -S guix repl --}
9990 Without a file name argument, a Guile REPL is started:
9994 scheme@@(guile-user)> ,use (gnu packages base)
9995 scheme@@(guile-user)> coreutils
9996 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
10000 In addition, @command{guix repl} implements a simple machine-readable REPL
10001 protocol for use by @code{(guix inferior)}, a facility to interact with
10002 @dfn{inferiors}, separate processes running a potentially different revision
10005 The available options are as follows:
10008 @item --type=@var{type}
10009 @itemx -t @var{type}
10010 Start a REPL of the given @var{TYPE}, which can be one of the following:
10014 This is default, and it spawns a standard full-featured Guile REPL.
10016 Spawn a REPL that uses the machine-readable protocol. This is the protocol
10017 that the @code{(guix inferior)} module speaks.
10020 @item --listen=@var{endpoint}
10021 By default, @command{guix repl} reads from standard input and writes to
10022 standard output. When this option is passed, it will instead listen for
10023 connections on @var{endpoint}. Here are examples of valid options:
10026 @item --listen=tcp:37146
10027 Accept connections on localhost on port 37146.
10029 @item --listen=unix:/tmp/socket
10030 Accept connections on the Unix-domain socket @file{/tmp/socket}.
10033 @item --load-path=@var{directory}
10034 @itemx -L @var{directory}
10035 Add @var{directory} to the front of the package module search path
10036 (@pxref{Package Modules}).
10038 This allows users to define their own packages and make them visible to
10039 the script or REPL.
10042 Inhibit loading of the @file{~/.guile} file. By default, that
10043 configuration file is loaded when spawning a @code{guile} REPL.
10046 @c *********************************************************************
10050 This section describes Guix command-line utilities. Some of them are
10051 primarily targeted at developers and users who write new package
10052 definitions, while others are more generally useful. They complement
10053 the Scheme programming interface of Guix in a convenient way.
10056 * Invoking guix build:: Building packages from the command line.
10057 * Invoking guix edit:: Editing package definitions.
10058 * Invoking guix download:: Downloading a file and printing its hash.
10059 * Invoking guix hash:: Computing the cryptographic hash of a file.
10060 * Invoking guix import:: Importing package definitions.
10061 * Invoking guix refresh:: Updating package definitions.
10062 * Invoking guix lint:: Finding errors in package definitions.
10063 * Invoking guix size:: Profiling disk usage.
10064 * Invoking guix graph:: Visualizing the graph of packages.
10065 * Invoking guix publish:: Sharing substitutes.
10066 * Invoking guix challenge:: Challenging substitute servers.
10067 * Invoking guix copy:: Copying to and from a remote store.
10068 * Invoking guix container:: Process isolation.
10069 * Invoking guix weather:: Assessing substitute availability.
10070 * Invoking guix processes:: Listing client processes.
10073 @node Invoking guix build
10074 @section Invoking @command{guix build}
10076 @cindex package building
10077 @cindex @command{guix build}
10078 The @command{guix build} command builds packages or derivations and
10079 their dependencies, and prints the resulting store paths. Note that it
10080 does not modify the user's profile---this is the job of the
10081 @command{guix package} command (@pxref{Invoking guix package}). Thus,
10082 it is mainly useful for distribution developers.
10084 The general syntax is:
10087 guix build @var{options} @var{package-or-derivation}@dots{}
10090 As an example, the following command builds the latest versions of Emacs
10091 and of Guile, displays their build logs, and finally displays the
10092 resulting directories:
10095 guix build emacs guile
10098 Similarly, the following command builds all the available packages:
10101 guix build --quiet --keep-going \
10102 `guix package -A | cut -f1,2 --output-delimiter=@@`
10105 @var{package-or-derivation} may be either the name of a package found in
10106 the software distribution such as @code{coreutils} or
10107 @code{coreutils@@8.20}, or a derivation such as
10108 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
10109 package with the corresponding name (and optionally version) is searched
10110 for among the GNU distribution modules (@pxref{Package Modules}).
10112 Alternatively, the @option{--expression} option may be used to specify a
10113 Scheme expression that evaluates to a package; this is useful when
10114 disambiguating among several same-named packages or package variants is
10117 There may be zero or more @var{options}. The available options are
10118 described in the subsections below.
10121 * Common Build Options:: Build options for most commands.
10122 * Package Transformation Options:: Creating variants of packages.
10123 * Additional Build Options:: Options specific to 'guix build'.
10124 * Debugging Build Failures:: Real life packaging experience.
10127 @node Common Build Options
10128 @subsection Common Build Options
10130 A number of options that control the build process are common to
10131 @command{guix build} and other commands that can spawn builds, such as
10132 @command{guix package} or @command{guix archive}. These are the
10137 @item --load-path=@var{directory}
10138 @itemx -L @var{directory}
10139 Add @var{directory} to the front of the package module search path
10140 (@pxref{Package Modules}).
10142 This allows users to define their own packages and make them visible to
10143 the command-line tools.
10145 @item --keep-failed
10147 Keep the build tree of failed builds. Thus, if a build fails, its build
10148 tree is kept under @file{/tmp}, in a directory whose name is shown at
10149 the end of the build log. This is useful when debugging build issues.
10150 @xref{Debugging Build Failures}, for tips and tricks on how to debug
10153 This option implies @option{--no-offload}, and it has no effect when
10154 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
10155 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
10159 Keep going when some of the derivations fail to build; return only once
10160 all the builds have either completed or failed.
10162 The default behavior is to stop as soon as one of the specified
10163 derivations has failed.
10167 Do not build the derivations.
10169 @anchor{fallback-option}
10171 When substituting a pre-built binary fails, fall back to building
10172 packages locally (@pxref{Substitution Failure}).
10174 @item --substitute-urls=@var{urls}
10175 @anchor{client-substitute-urls}
10176 Consider @var{urls} the whitespace-separated list of substitute source
10177 URLs, overriding the default list of URLs of @command{guix-daemon}
10178 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
10180 This means that substitutes may be downloaded from @var{urls}, provided
10181 they are signed by a key authorized by the system administrator
10182 (@pxref{Substitutes}).
10184 When @var{urls} is the empty string, substitutes are effectively
10187 @item --no-substitutes
10188 Do not use substitutes for build products. That is, always build things
10189 locally instead of allowing downloads of pre-built binaries
10190 (@pxref{Substitutes}).
10193 Do not ``graft'' packages. In practice, this means that package updates
10194 available as grafts are not applied. @xref{Security Updates}, for more
10195 information on grafts.
10197 @item --rounds=@var{n}
10198 Build each derivation @var{n} times in a row, and raise an error if
10199 consecutive build results are not bit-for-bit identical.
10201 This is a useful way to detect non-deterministic builds processes.
10202 Non-deterministic build processes are a problem because they make it
10203 practically impossible for users to @emph{verify} whether third-party
10204 binaries are genuine. @xref{Invoking guix challenge}, for more.
10206 When used in conjunction with @option{--keep-failed}, the differing
10207 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
10208 This makes it easy to look for differences between the two results.
10211 Do not use offload builds to other machines (@pxref{Daemon Offload
10212 Setup}). That is, always build things locally instead of offloading
10213 builds to remote machines.
10215 @item --max-silent-time=@var{seconds}
10216 When the build or substitution process remains silent for more than
10217 @var{seconds}, terminate it and report a build failure.
10219 By default, the daemon's setting is honored (@pxref{Invoking
10220 guix-daemon, @option{--max-silent-time}}).
10222 @item --timeout=@var{seconds}
10223 Likewise, when the build or substitution process lasts for more than
10224 @var{seconds}, terminate it and report a build failure.
10226 By default, the daemon's setting is honored (@pxref{Invoking
10227 guix-daemon, @option{--timeout}}).
10229 @c Note: This option is actually not part of %standard-build-options but
10230 @c most programs honor it.
10231 @cindex verbosity, of the command-line tools
10232 @cindex build logs, verbosity
10233 @item -v @var{level}
10234 @itemx --verbosity=@var{level}
10235 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
10236 output is produced, 1 is for quiet output, and 2 shows all the build log
10237 output on standard error.
10239 @item --cores=@var{n}
10241 Allow the use of up to @var{n} CPU cores for the build. The special
10242 value @code{0} means to use as many CPU cores as available.
10244 @item --max-jobs=@var{n}
10246 Allow at most @var{n} build jobs in parallel. @xref{Invoking
10247 guix-daemon, @option{--max-jobs}}, for details about this option and the
10248 equivalent @command{guix-daemon} option.
10250 @item --debug=@var{level}
10251 Produce debugging output coming from the build daemon. @var{level} must be an
10252 integer between 0 and 5; higher means more verbose output. Setting a level of
10253 4 or more may be helpful when debugging setup issues with the build daemon.
10257 Behind the scenes, @command{guix build} is essentially an interface to
10258 the @code{package-derivation} procedure of the @code{(guix packages)}
10259 module, and to the @code{build-derivations} procedure of the @code{(guix
10260 derivations)} module.
10262 In addition to options explicitly passed on the command line,
10263 @command{guix build} and other @command{guix} commands that support
10264 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
10266 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
10267 Users can define this variable to a list of command line options that
10268 will automatically be used by @command{guix build} and other
10269 @command{guix} commands that can perform builds, as in the example
10273 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
10276 These options are parsed independently, and the result is appended to
10277 the parsed command-line options.
10281 @node Package Transformation Options
10282 @subsection Package Transformation Options
10284 @cindex package variants
10285 Another set of command-line options supported by @command{guix build}
10286 and also @command{guix package} are @dfn{package transformation
10287 options}. These are options that make it possible to define @dfn{package
10288 variants}---for instance, packages built from different source code.
10289 This is a convenient way to create customized packages on the fly
10290 without having to type in the definitions of package variants
10291 (@pxref{Defining Packages}).
10293 Package transformation options are preserved across upgrades:
10294 @command{guix upgrade} attempts to apply transformation options
10295 initially used when creating the profile to the upgraded packages.
10297 The available options are listed below. Most commands support them and
10298 also support a @option{--help-transform} option that lists all the
10299 available options and a synopsis (these options are not shown in the
10300 @option{--help} output for brevity).
10304 @item --with-source=@var{source}
10305 @itemx --with-source=@var{package}=@var{source}
10306 @itemx --with-source=@var{package}@@@var{version}=@var{source}
10307 Use @var{source} as the source of @var{package}, and @var{version} as
10308 its version number.
10309 @var{source} must be a file name or a URL, as for @command{guix
10310 download} (@pxref{Invoking guix download}).
10312 When @var{package} is omitted,
10313 it is taken to be the package name specified on the
10314 command line that matches the base of @var{source}---e.g.,
10315 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
10316 package is @code{guile}.
10318 Likewise, when @var{version} is omitted, the version string is inferred from
10319 @var{source}; in the previous example, it is @code{2.0.10}.
10321 This option allows users to try out versions of packages other than the
10322 one provided by the distribution. The example below downloads
10323 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
10324 the @code{ed} package:
10327 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
10330 As a developer, @option{--with-source} makes it easy to test release
10334 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
10337 @dots{} or to build from a checkout in a pristine environment:
10340 $ git clone git://git.sv.gnu.org/guix.git
10341 $ guix build guix --with-source=guix@@1.0=./guix
10344 @item --with-input=@var{package}=@var{replacement}
10345 Replace dependency on @var{package} by a dependency on
10346 @var{replacement}. @var{package} must be a package name, and
10347 @var{replacement} must be a package specification such as @code{guile}
10348 or @code{guile@@1.8}.
10350 For instance, the following command builds Guix, but replaces its
10351 dependency on the current stable version of Guile with a dependency on
10352 the legacy version of Guile, @code{guile@@2.0}:
10355 guix build --with-input=guile=guile@@2.0 guix
10358 This is a recursive, deep replacement. So in this example, both
10359 @code{guix} and its dependency @code{guile-json} (which also depends on
10360 @code{guile}) get rebuilt against @code{guile@@2.0}.
10362 This is implemented using the @code{package-input-rewriting} Scheme
10363 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
10365 @item --with-graft=@var{package}=@var{replacement}
10366 This is similar to @option{--with-input} but with an important difference:
10367 instead of rebuilding the whole dependency chain, @var{replacement} is
10368 built and then @dfn{grafted} onto the binaries that were initially
10369 referring to @var{package}. @xref{Security Updates}, for more
10370 information on grafts.
10372 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
10373 and all its dependencies, replacing references to the version of GnuTLS
10374 they currently refer to:
10377 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
10380 This has the advantage of being much faster than rebuilding everything.
10381 But there is a caveat: it works if and only if @var{package} and
10382 @var{replacement} are strictly compatible---for example, if they provide
10383 a library, the application binary interface (ABI) of those libraries
10384 must be compatible. If @var{replacement} is somehow incompatible with
10385 @var{package}, then the resulting package may be unusable. Use with
10388 @cindex debugging info, rebuilding
10389 @item --with-debug-info=@var{package}
10390 Build @var{package} in a way that preserves its debugging info and graft
10391 it onto packages that depend on it. This is useful if @var{package}
10392 does not already provide debugging info as a @code{debug} output
10393 (@pxref{Installing Debugging Files}).
10395 For example, suppose you're experiencing a crash in Inkscape and would
10396 like to see what's up in GLib, a library deep down in Inkscape's
10397 dependency graph. GLib lacks a @code{debug} output, so debugging is
10398 tough. Fortunately, you rebuild GLib with debugging info and tack it on
10402 guix install inkscape --with-debug-info=glib
10405 Only GLib needs to be recompiled so this takes a reasonable amount of
10406 time. @xref{Installing Debugging Files}, for more info.
10409 Under the hood, this option works by passing the @samp{#:strip-binaries?
10410 #f} to the build system of the package of interest (@pxref{Build
10411 Systems}). Most build systems support that option but some do not. In
10412 that case, an error is raised.
10414 Likewise, if a C/C++ package is built without @code{-g} (which is rarely
10415 the case), debugging info will remain unavailable even when
10416 @code{#:strip-binaries?} is false.
10419 @cindex tool chain, changing the build tool chain of a package
10420 @item --with-c-toolchain=@var{package}=@var{toolchain}
10421 This option changes the compilation of @var{package} and everything that
10422 depends on it so that they get built with @var{toolchain} instead of the
10423 default GNU tool chain for C/C++.
10425 Consider this example:
10428 guix build octave-cli \
10429 --with-c-toolchain=fftw=gcc-toolchain@@10 \
10430 --with-c-toolchain=fftwf=gcc-toolchain@@10
10433 The command above builds a variant of the @code{fftw} and @code{fftwf}
10434 packages using version 10 of @code{gcc-toolchain} instead of the default
10435 tool chain, and then builds a variant of the GNU@tie{}Octave
10436 command-line interface using them. GNU@tie{}Octave itself is also built
10437 with @code{gcc-toolchain@@10}.
10439 This other example builds the Hardware Locality (@code{hwloc}) library
10440 and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
10444 guix build --with-c-toolchain=hwloc=clang-toolchain \
10445 intel-mpi-benchmarks
10449 There can be application binary interface (ABI) incompatibilities among
10450 tool chains. This is particularly true of the C++ standard library and
10451 run-time support libraries such as that of OpenMP@. By rebuilding all
10452 dependents with the same tool chain, @option{--with-c-toolchain} minimizes
10453 the risks of incompatibility but cannot entirely eliminate them. Choose
10454 @var{package} wisely.
10457 @item --with-git-url=@var{package}=@var{url}
10458 @cindex Git, using the latest commit
10459 @cindex latest commit, building
10460 Build @var{package} from the latest commit of the @code{master} branch of the
10461 Git repository at @var{url}. Git sub-modules of the repository are fetched,
10464 For example, the following command builds the NumPy Python library against the
10465 latest commit of the master branch of Python itself:
10468 guix build python-numpy \
10469 --with-git-url=python=https://github.com/python/cpython
10472 This option can also be combined with @option{--with-branch} or
10473 @option{--with-commit} (see below).
10475 @cindex continuous integration
10476 Obviously, since it uses the latest commit of the given branch, the result of
10477 such a command varies over time. Nevertheless it is a convenient way to
10478 rebuild entire software stacks against the latest commit of one or more
10479 packages. This is particularly useful in the context of continuous
10482 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
10483 consecutive accesses to the same repository. You may want to clean it up once
10484 in a while to save disk space.
10486 @item --with-branch=@var{package}=@var{branch}
10487 Build @var{package} from the latest commit of @var{branch}. If the
10488 @code{source} field of @var{package} is an origin with the @code{git-fetch}
10489 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
10490 repository URL is taken from that @code{source}. Otherwise you have to use
10491 @option{--with-git-url} to specify the URL of the Git repository.
10493 For instance, the following command builds @code{guile-sqlite3} from the
10494 latest commit of its @code{master} branch, and then builds @code{guix} (which
10495 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
10496 specific @code{guile-sqlite3} build:
10499 guix build --with-branch=guile-sqlite3=master cuirass
10502 @item --with-commit=@var{package}=@var{commit}
10503 This is similar to @option{--with-branch}, except that it builds from
10504 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
10505 Git commit SHA1 identifier or a tag.
10507 @item --with-patch=@var{package}=@var{file}
10508 Add @var{file} to the list of patches applied to @var{package}, where
10509 @var{package} is a spec such as @code{python@@3.8} or @code{glibc}.
10510 @var{file} must contain a patch; it is applied with the flags specified
10511 in the @code{origin} of @var{package} (@pxref{origin Reference}), which
10512 by default includes @code{-p1} (@pxref{patch Directories,,, diffutils,
10513 Comparing and Merging Files}).
10515 As an example, the command below rebuilds Coreutils with the GNU C
10516 Library (glibc) patched with the given patch:
10519 guix build coreutils --with-patch=glibc=./glibc-frob.patch
10522 In this example, glibc itself as well as everything that leads to
10523 Coreutils in the dependency graph is rebuilt.
10525 @cindex upstream, latest version
10526 @item --with-latest=@var{package}
10527 So you like living on the bleeding edge? This option is for you! It
10528 replaces occurrences of @var{package} in the dependency graph with its
10529 latest upstream version, as reported by @command{guix refresh}
10530 (@pxref{Invoking guix refresh}).
10532 It does so by determining the latest upstream release of @var{package}
10533 (if possible), downloading it, and authenticating it @emph{if} it comes
10534 with an OpenPGP signature.
10536 As an example, the command below builds Guix against the latest version
10540 guix build guix --with-latest=guile-json
10543 There are limitations. First, in cases where the tool cannot or does
10544 not know how to authenticate source code, you are at risk of running
10545 malicious code; a warning is emitted in this case. Second, this option
10546 simply changes the source used in the existing package definitions,
10547 which is not always sufficient: there might be additional dependencies
10548 that need to be added, patches to apply, and more generally the quality
10549 assurance work that Guix developers normally do will be missing.
10551 You've been warned! In all the other cases, it's a snappy way to stay
10552 on top. We encourage you to submit patches updating the actual package
10553 definitions once you have successfully tested an upgrade
10554 (@pxref{Contributing}).
10556 @cindex test suite, skipping
10557 @item --without-tests=@var{package}
10558 Build @var{package} without running its tests. This can be useful in
10559 situations where you want to skip the lengthy test suite of a
10560 intermediate package, or if a package's test suite fails in a
10561 non-deterministic fashion. It should be used with care because running
10562 the test suite is a good way to ensure a package is working as intended.
10564 Turning off tests leads to a different store item. Consequently, when
10565 using this option, anything that depends on @var{package} must be
10566 rebuilt, as in this example:
10569 guix install --without-tests=python python-notebook
10572 The command above installs @code{python-notebook} on top of
10573 @code{python} built without running its test suite. To do so, it also
10574 rebuilds everything that depends on @code{python}, including
10575 @code{python-notebook} itself.
10577 Internally, @option{--without-tests} relies on changing the
10578 @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
10579 Systems}). Note that some packages use a customized @code{check} phase
10580 that does not respect a @code{#:tests? #f} setting. Therefore,
10581 @option{--without-tests} has no effect on these packages.
10585 Wondering how to achieve the same effect using Scheme code, for example
10586 in your manifest, or how to write your own package transformation?
10587 @xref{Defining Package Variants}, for an overview of the programming
10588 interfaces available.
10590 @node Additional Build Options
10591 @subsection Additional Build Options
10593 The command-line options presented below are specific to @command{guix
10600 Build quietly, without displaying the build log; this is equivalent to
10601 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
10602 (or similar) and can always be retrieved using the @option{--log-file} option.
10604 @item --file=@var{file}
10605 @itemx -f @var{file}
10606 Build the package, derivation, or other file-like object that the code within
10607 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
10609 As an example, @var{file} might contain a package definition like this
10610 (@pxref{Defining Packages}):
10613 @include package-hello.scm
10616 The @var{file} may also contain a JSON representation of one or more
10617 package definitions. Running @code{guix build -f} on @file{hello.json}
10618 with the following contents would result in building the packages
10619 @code{myhello} and @code{greeter}:
10622 @verbatiminclude package-hello.json
10625 @item --manifest=@var{manifest}
10626 @itemx -m @var{manifest}
10627 Build all packages listed in the given @var{manifest}
10628 (@pxref{profile-manifest, @option{--manifest}}).
10630 @item --expression=@var{expr}
10631 @itemx -e @var{expr}
10632 Build the package or derivation @var{expr} evaluates to.
10634 For example, @var{expr} may be @code{(@@ (gnu packages guile)
10635 guile-1.8)}, which unambiguously designates this specific variant of
10636 version 1.8 of Guile.
10638 Alternatively, @var{expr} may be a G-expression, in which case it is used
10639 as a build program passed to @code{gexp->derivation}
10640 (@pxref{G-Expressions}).
10642 Lastly, @var{expr} may refer to a zero-argument monadic procedure
10643 (@pxref{The Store Monad}). The procedure must return a derivation as a
10644 monadic value, which is then passed through @code{run-with-store}.
10648 Build the source derivations of the packages, rather than the packages
10651 For instance, @code{guix build -S gcc} returns something like
10652 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
10655 The returned source tarball is the result of applying any patches and
10656 code snippets specified in the package @code{origin} (@pxref{Defining
10659 @cindex source, verification
10660 As with other derivations, the result of building a source derivation
10661 can be verified using the @option{--check} option (@pxref{build-check}).
10662 This is useful to validate that a (potentially already built or
10663 substituted, thus cached) package source matches against its declared
10666 Note that @command{guix build -S} compiles the sources only of the
10667 specified packages. They do not include the sources of statically
10668 linked dependencies and by themselves are insufficient for reproducing
10672 Fetch and return the source of @var{package-or-derivation} and all their
10673 dependencies, recursively. This is a handy way to obtain a local copy
10674 of all the source code needed to build @var{packages}, allowing you to
10675 eventually build them even without network access. It is an extension
10676 of the @option{--source} option and can accept one of the following
10677 optional argument values:
10681 This value causes the @option{--sources} option to behave in the same way
10682 as the @option{--source} option.
10685 Build the source derivations of all packages, including any source that
10686 might be listed as @code{inputs}. This is the default value.
10689 $ guix build --sources tzdata
10690 The following derivations will be built:
10691 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
10692 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
10696 Build the source derivations of all packages, as well of all transitive
10697 inputs to the packages. This can be used e.g.@: to
10698 prefetch package source for later offline building.
10701 $ guix build --sources=transitive tzdata
10702 The following derivations will be built:
10703 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
10704 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
10705 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
10706 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
10707 /gnu/store/@dots{}-make-4.1.tar.xz.drv
10708 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
10714 @item --system=@var{system}
10715 @itemx -s @var{system}
10716 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
10717 the system type of the build host. The @command{guix build} command allows
10718 you to repeat this option several times, in which case it builds for all the
10719 specified systems; other commands ignore extraneous @option{-s} options.
10722 The @option{--system} flag is for @emph{native} compilation and must not
10723 be confused with cross-compilation. See @option{--target} below for
10724 information on cross-compilation.
10727 An example use of this is on Linux-based systems, which can emulate
10728 different personalities. For instance, passing
10729 @option{--system=i686-linux} on an @code{x86_64-linux} system or
10730 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
10731 you to build packages in a complete 32-bit environment.
10734 Building for an @code{armhf-linux} system is unconditionally enabled on
10735 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
10736 allow for this functionality, notably the ThunderX.
10739 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
10740 is enabled (@pxref{Virtualization Services,
10741 @code{qemu-binfmt-service-type}}), you can build for any system for
10742 which a QEMU @code{binfmt_misc} handler is installed.
10744 Builds for a system other than that of the machine you are using can
10745 also be offloaded to a remote machine of the right architecture.
10746 @xref{Daemon Offload Setup}, for more information on offloading.
10748 @item --target=@var{triplet}
10749 @cindex cross-compilation
10750 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
10751 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
10752 configuration triplets,, autoconf, Autoconf}).
10754 @anchor{build-check}
10756 @cindex determinism, checking
10757 @cindex reproducibility, checking
10758 Rebuild @var{package-or-derivation}, which are already available in the
10759 store, and raise an error if the build results are not bit-for-bit
10762 This mechanism allows you to check whether previously installed
10763 substitutes are genuine (@pxref{Substitutes}), or whether the build result
10764 of a package is deterministic. @xref{Invoking guix challenge}, for more
10765 background information and tools.
10767 When used in conjunction with @option{--keep-failed}, the differing
10768 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
10769 This makes it easy to look for differences between the two results.
10772 @cindex repairing store items
10773 @cindex corruption, recovering from
10774 Attempt to repair the specified store items, if they are corrupt, by
10775 re-downloading or rebuilding them.
10777 This operation is not atomic and thus restricted to @code{root}.
10779 @item --derivations
10781 Return the derivation paths, not the output paths, of the given
10784 @item --root=@var{file}
10785 @itemx -r @var{file}
10786 @cindex GC roots, adding
10787 @cindex garbage collector roots, adding
10788 Make @var{file} a symlink to the result, and register it as a garbage
10791 Consequently, the results of this @command{guix build} invocation are
10792 protected from garbage collection until @var{file} is removed. When
10793 that option is omitted, build results are eligible for garbage
10794 collection as soon as the build completes. @xref{Invoking guix gc}, for
10798 @cindex build logs, access
10799 Return the build log file names or URLs for the given
10800 @var{package-or-derivation}, or raise an error if build logs are
10803 This works regardless of how packages or derivations are specified. For
10804 instance, the following invocations are equivalent:
10807 guix build --log-file `guix build -d guile`
10808 guix build --log-file `guix build guile`
10809 guix build --log-file guile
10810 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
10813 If a log is unavailable locally, and unless @option{--no-substitutes} is
10814 passed, the command looks for a corresponding log on one of the
10815 substitute servers (as specified with @option{--substitute-urls}).
10817 So for instance, imagine you want to see the build log of GDB on MIPS,
10818 but you are actually on an @code{x86_64} machine:
10821 $ guix build --log-file gdb -s aarch64-linux
10822 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
10825 You can freely access a huge library of build logs!
10828 @node Debugging Build Failures
10829 @subsection Debugging Build Failures
10831 @cindex build failures, debugging
10832 When defining a new package (@pxref{Defining Packages}), you will
10833 probably find yourself spending some time debugging and tweaking the
10834 build until it succeeds. To do that, you need to operate the build
10835 commands yourself in an environment as close as possible to the one the
10838 To that end, the first thing to do is to use the @option{--keep-failed}
10839 or @option{-K} option of @command{guix build}, which will keep the
10840 failed build tree in @file{/tmp} or whatever directory you specified as
10841 @env{TMPDIR} (@pxref{Common Build Options, @option{--keep-failed}}).
10843 From there on, you can @command{cd} to the failed build tree and source
10844 the @file{environment-variables} file, which contains all the
10845 environment variable definitions that were in place when the build
10846 failed. So let's say you're debugging a build failure in package
10847 @code{foo}; a typical session would look like this:
10850 $ guix build foo -K
10851 @dots{} @i{build fails}
10852 $ cd /tmp/guix-build-foo.drv-0
10853 $ source ./environment-variables
10857 Now, you can invoke commands as if you were the daemon (almost) and
10858 troubleshoot your build process.
10860 Sometimes it happens that, for example, a package's tests pass when you
10861 run them manually but they fail when the daemon runs them. This can
10862 happen because the daemon runs builds in containers where, unlike in our
10863 environment above, network access is missing, @file{/bin/sh} does not
10864 exist, etc. (@pxref{Build Environment Setup}).
10866 In such cases, you may need to run inspect the build process from within
10867 a container similar to the one the build daemon creates:
10870 $ guix build -K foo
10872 $ cd /tmp/guix-build-foo.drv-0
10873 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
10874 [env]# source ./environment-variables
10878 Here, @command{guix environment -C} creates a container and spawns a new
10879 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
10880 strace gdb} part adds the @command{strace} and @command{gdb} commands to
10881 the container, which you may find handy while debugging. The
10882 @option{--no-grafts} option makes sure we get the exact same
10883 environment, with ungrafted packages (@pxref{Security Updates}, for more
10886 To get closer to a container like that used by the build daemon, we can
10887 remove @file{/bin/sh}:
10893 (Don't worry, this is harmless: this is all happening in the throw-away
10894 container created by @command{guix environment}.)
10896 The @command{strace} command is probably not in the search path, but we
10900 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
10903 In this way, not only you will have reproduced the environment variables
10904 the daemon uses, you will also be running the build process in a container
10905 similar to the one the daemon uses.
10908 @node Invoking guix edit
10909 @section Invoking @command{guix edit}
10911 @cindex @command{guix edit}
10912 @cindex package definition, editing
10913 So many packages, so many source files! The @command{guix edit} command
10914 facilitates the life of users and packagers by pointing their editor at
10915 the source file containing the definition of the specified packages.
10919 guix edit gcc@@4.9 vim
10923 launches the program specified in the @env{VISUAL} or in the
10924 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
10927 If you are using a Guix Git checkout (@pxref{Building from Git}), or
10928 have created your own packages on @env{GUIX_PACKAGE_PATH}
10929 (@pxref{Package Modules}), you will be able to edit the package
10930 recipes. In other cases, you will be able to examine the read-only recipes
10931 for packages currently in the store.
10933 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
10934 @option{--load-path=@var{directory}} (or in short @option{-L
10935 @var{directory}}) allows you to add @var{directory} to the front of the
10936 package module search path and so make your own packages visible.
10938 @node Invoking guix download
10939 @section Invoking @command{guix download}
10941 @cindex @command{guix download}
10942 @cindex downloading package sources
10943 When writing a package definition, developers typically need to download
10944 a source tarball, compute its SHA256 hash, and write that
10945 hash in the package definition (@pxref{Defining Packages}). The
10946 @command{guix download} tool helps with this task: it downloads a file
10947 from the given URI, adds it to the store, and prints both its file name
10948 in the store and its SHA256 hash.
10950 The fact that the downloaded file is added to the store saves bandwidth:
10951 when the developer eventually tries to build the newly defined package
10952 with @command{guix build}, the source tarball will not have to be
10953 downloaded again because it is already in the store. It is also a
10954 convenient way to temporarily stash files, which may be deleted
10955 eventually (@pxref{Invoking guix gc}).
10957 The @command{guix download} command supports the same URIs as used in
10958 package definitions. In particular, it supports @code{mirror://} URIs.
10959 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
10960 Guile bindings for GnuTLS are available in the user's environment; when
10961 they are not available, an error is raised. @xref{Guile Preparations,
10962 how to install the GnuTLS bindings for Guile,, gnutls-guile,
10963 GnuTLS-Guile}, for more information.
10965 @command{guix download} verifies HTTPS server certificates by loading
10966 the certificates of X.509 authorities from the directory pointed to by
10967 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
10968 Certificates}), unless @option{--no-check-certificate} is used.
10970 The following options are available:
10973 @item --hash=@var{algorithm}
10974 @itemx -H @var{algorithm}
10975 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
10976 hash}, for more information.
10978 @item --format=@var{fmt}
10979 @itemx -f @var{fmt}
10980 Write the hash in the format specified by @var{fmt}. For more
10981 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
10983 @item --no-check-certificate
10984 Do not validate the X.509 certificates of HTTPS servers.
10986 When using this option, you have @emph{absolutely no guarantee} that you
10987 are communicating with the authentic server responsible for the given
10988 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
10990 @item --output=@var{file}
10991 @itemx -o @var{file}
10992 Save the downloaded file to @var{file} instead of adding it to the
10996 @node Invoking guix hash
10997 @section Invoking @command{guix hash}
10999 @cindex @command{guix hash}
11000 The @command{guix hash} command computes the hash of a file.
11001 It is primarily a convenience tool for anyone contributing to the
11002 distribution: it computes the cryptographic hash of a file, which can be
11003 used in the definition of a package (@pxref{Defining Packages}).
11005 The general syntax is:
11008 guix hash @var{option} @var{file}
11011 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
11012 hash of data read from standard input. @command{guix hash} has the
11017 @item --hash=@var{algorithm}
11018 @itemx -H @var{algorithm}
11019 Compute a hash using the specified @var{algorithm}, @code{sha256} by
11022 @var{algorithm} must the name of a cryptographic hash algorithm
11023 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
11024 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
11025 Reference Manual}).
11027 @item --format=@var{fmt}
11028 @itemx -f @var{fmt}
11029 Write the hash in the format specified by @var{fmt}.
11031 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
11032 (@code{hex} and @code{hexadecimal} can be used as well).
11034 If the @option{--format} option is not specified, @command{guix hash}
11035 will output the hash in @code{nix-base32}. This representation is used
11036 in the definitions of packages.
11040 Compute the hash on @var{file} recursively.
11042 In this case, the hash is computed on an archive containing @var{file},
11043 including its children if it is a directory. Some of the metadata of
11044 @var{file} is part of the archive; for instance, when @var{file} is a
11045 regular file, the hash is different depending on whether @var{file} is
11046 executable or not. Metadata such as time stamps has no impact on the
11047 hash (@pxref{Invoking guix archive}).
11048 @c FIXME: Replace xref above with xref to an ``Archive'' section when
11051 @item --exclude-vcs
11053 When combined with @option{--recursive}, exclude version control system
11054 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
11057 As an example, here is how you would compute the hash of a Git checkout,
11058 which is useful when using the @code{git-fetch} method (@pxref{origin
11062 $ git clone http://example.org/foo.git
11068 @node Invoking guix import
11069 @section Invoking @command{guix import}
11071 @cindex importing packages
11072 @cindex package import
11073 @cindex package conversion
11074 @cindex Invoking @command{guix import}
11075 The @command{guix import} command is useful for people who would like to
11076 add a package to the distribution with as little work as
11077 possible---a legitimate demand. The command knows of a few
11078 repositories from which it can ``import'' package metadata. The result
11079 is a package definition, or a template thereof, in the format we know
11080 (@pxref{Defining Packages}).
11082 The general syntax is:
11085 guix import @var{importer} @var{options}@dots{}
11088 @var{importer} specifies the source from which to import package
11089 metadata, and @var{options} specifies a package identifier and other
11090 options specific to @var{importer}.
11092 Some of the importers rely on the ability to run the @command{gpgv} command.
11093 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
11096 Currently, the available ``importers'' are:
11100 Import metadata for the given GNU package. This provides a template
11101 for the latest version of that GNU package, including the hash of its
11102 source tarball, and its canonical synopsis and description.
11104 Additional information such as the package dependencies and its
11105 license needs to be figured out manually.
11107 For example, the following command returns a package definition for
11111 guix import gnu hello
11114 Specific command-line options are:
11117 @item --key-download=@var{policy}
11118 As for @command{guix refresh}, specify the policy to handle missing
11119 OpenPGP keys when verifying the package signature. @xref{Invoking guix
11120 refresh, @option{--key-download}}.
11125 Import metadata from the @uref{https://pypi.python.org/, Python Package
11126 Index}. Information is taken from the JSON-formatted description
11127 available at @code{pypi.python.org} and usually includes all the relevant
11128 information, including package dependencies. For maximum efficiency, it
11129 is recommended to install the @command{unzip} utility, so that the
11130 importer can unzip Python wheels and gather data from them.
11132 The command below imports metadata for the @code{itsdangerous} Python
11136 guix import pypi itsdangerous
11142 Traverse the dependency graph of the given upstream package recursively
11143 and generate package expressions for all those packages that are not yet
11149 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
11150 is taken from the JSON-formatted description available at
11151 @code{rubygems.org} and includes most relevant information, including
11152 runtime dependencies. There are some caveats, however. The metadata
11153 doesn't distinguish between synopses and descriptions, so the same string
11154 is used for both fields. Additionally, the details of non-Ruby
11155 dependencies required to build native extensions is unavailable and left
11156 as an exercise to the packager.
11158 The command below imports metadata for the @code{rails} Ruby package:
11161 guix import gem rails
11167 Traverse the dependency graph of the given upstream package recursively
11168 and generate package expressions for all those packages that are not yet
11174 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
11175 Information is taken from the JSON-formatted metadata provided through
11176 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
11177 relevant information, such as module dependencies. License information
11178 should be checked closely. If Perl is available in the store, then the
11179 @code{corelist} utility will be used to filter core modules out of the
11180 list of dependencies.
11182 The command command below imports metadata for the Acme::Boolean Perl
11186 guix import cpan Acme::Boolean
11191 @cindex Bioconductor
11192 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
11193 central repository for the @uref{https://r-project.org, GNU@tie{}R
11194 statistical and graphical environment}.
11196 Information is extracted from the @file{DESCRIPTION} file of the package.
11198 The command command below imports metadata for the Cairo R package:
11201 guix import cran Cairo
11204 When @option{--recursive} is added, the importer will traverse the
11205 dependency graph of the given upstream package recursively and generate
11206 package expressions for all those packages that are not yet in Guix.
11208 When @option{--style=specification} is added, the importer will generate
11209 package definitions whose inputs are package specifications instead of
11210 references to package variables. This is useful when generated package
11211 definitions are to be appended to existing user modules, as the list of
11212 used package modules need not be changed. The default is
11213 @option{--style=variable}.
11215 When @option{--archive=bioconductor} is added, metadata is imported from
11216 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
11217 packages for the analysis and comprehension of high-throughput
11218 genomic data in bioinformatics.
11220 Information is extracted from the @file{DESCRIPTION} file contained in the
11223 The command below imports metadata for the GenomicRanges R package:
11226 guix import cran --archive=bioconductor GenomicRanges
11229 Finally, you can also import R packages that have not yet been published on
11230 CRAN or Bioconductor as long as they are in a git repository. Use
11231 @option{--archive=git} followed by the URL of the git repository:
11234 guix import cran --archive=git https://github.com/immunogenomics/harmony
11240 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
11241 comprehensive TeX archive network for TeX packages that are part of the
11242 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
11244 Information about the package is obtained through the XML API provided
11245 by CTAN, while the source code is downloaded from the SVN repository of
11246 the Tex Live project. This is done because the CTAN does not keep
11247 versioned archives.
11249 The command command below imports metadata for the @code{fontspec}
11253 guix import texlive fontspec
11256 When @option{--archive=@var{directory}} is added, the source code is
11257 downloaded not from the @file{latex} sub-directory of the
11258 @file{texmf-dist/source} tree in the TeX Live SVN repository, but from
11259 the specified sibling @var{directory} under the same root.
11261 The command below imports metadata for the @code{ifxetex} package from
11262 CTAN while fetching the sources from the directory
11263 @file{texmf/source/generic}:
11266 guix import texlive --archive=generic ifxetex
11270 @cindex JSON, import
11271 Import package metadata from a local JSON file. Consider the following
11272 example package definition in JSON format:
11278 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
11279 "build-system": "gnu",
11280 "home-page": "https://www.gnu.org/software/hello/",
11281 "synopsis": "Hello, GNU world: An example GNU package",
11282 "description": "GNU Hello prints a greeting.",
11283 "license": "GPL-3.0+",
11284 "native-inputs": ["gettext"]
11288 The field names are the same as for the @code{<package>} record
11289 (@xref{Defining Packages}). References to other packages are provided
11290 as JSON lists of quoted package specification strings such as
11291 @code{guile} or @code{guile@@2.0}.
11293 The importer also supports a more explicit source definition using the
11294 common fields for @code{<origin>} records:
11300 "method": "url-fetch",
11301 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
11303 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
11310 The command below reads metadata from the JSON file @code{hello.json}
11311 and outputs a package expression:
11314 guix import json hello.json
11318 Import metadata from a local copy of the source of the
11319 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
11320 relies on the @command{nix-instantiate} command of
11321 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
11322 typically written in a mixture of Nix-language and Bash code. This
11323 command only imports the high-level package structure that is written in
11324 the Nix language. It normally includes all the basic fields of a
11325 package definition.
11327 When importing a GNU package, the synopsis and descriptions are replaced
11328 by their canonical upstream variant.
11330 Usually, you will first need to do:
11333 export NIX_REMOTE=daemon
11337 so that @command{nix-instantiate} does not try to open the Nix database.
11339 As an example, the command below imports the package definition of
11340 LibreOffice (more precisely, it imports the definition of the package
11341 bound to the @code{libreoffice} top-level attribute):
11344 guix import nix ~/path/to/nixpkgs libreoffice
11349 Import metadata from the Haskell community's central package archive
11350 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
11351 Cabal files and includes all the relevant information, including package
11354 Specific command-line options are:
11359 Read a Cabal file from standard input.
11360 @item --no-test-dependencies
11362 Do not include dependencies required only by the test suites.
11363 @item --cabal-environment=@var{alist}
11364 @itemx -e @var{alist}
11365 @var{alist} is a Scheme alist defining the environment in which the
11366 Cabal conditionals are evaluated. The accepted keys are: @code{os},
11367 @code{arch}, @code{impl} and a string representing the name of a flag.
11368 The value associated with a flag has to be either the symbol
11369 @code{true} or @code{false}. The value associated with other keys
11370 has to conform to the Cabal file format definition. The default value
11371 associated with the keys @code{os}, @code{arch} and @code{impl} is
11372 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
11375 Traverse the dependency graph of the given upstream package recursively
11376 and generate package expressions for all those packages that are not yet
11380 The command below imports metadata for the latest version of the
11381 HTTP Haskell package without including test dependencies and
11382 specifying the value of the flag @samp{network-uri} as @code{false}:
11385 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
11388 A specific package version may optionally be specified by following the
11389 package name by an at-sign and a version number as in the following example:
11392 guix import hackage mtl@@2.1.3.1
11397 The @code{stackage} importer is a wrapper around the @code{hackage} one.
11398 It takes a package name, looks up the package version included in a
11399 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
11400 release and uses the @code{hackage} importer to retrieve its metadata.
11401 Note that it is up to you to select an LTS release compatible with the
11402 GHC compiler used by Guix.
11404 Specific command-line options are:
11407 @item --no-test-dependencies
11409 Do not include dependencies required only by the test suites.
11410 @item --lts-version=@var{version}
11411 @itemx -l @var{version}
11412 @var{version} is the desired LTS release version. If omitted the latest
11416 Traverse the dependency graph of the given upstream package recursively
11417 and generate package expressions for all those packages that are not yet
11421 The command below imports metadata for the HTTP Haskell package
11422 included in the LTS Stackage release version 7.18:
11425 guix import stackage --lts-version=7.18 HTTP
11430 Import metadata from an Emacs Lisp Package Archive (ELPA) package
11431 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
11433 Specific command-line options are:
11436 @item --archive=@var{repo}
11437 @itemx -a @var{repo}
11438 @var{repo} identifies the archive repository from which to retrieve the
11439 information. Currently the supported repositories and their identifiers
11443 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
11444 identifier. This is the default.
11446 Packages from @code{elpa.gnu.org} are signed with one of the keys
11447 contained in the GnuPG keyring at
11448 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
11449 @code{emacs} package (@pxref{Package Installation, ELPA package
11450 signatures,, emacs, The GNU Emacs Manual}).
11453 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
11454 @code{melpa-stable} identifier.
11457 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
11463 Traverse the dependency graph of the given upstream package recursively
11464 and generate package expressions for all those packages that are not yet
11470 Import metadata from the crates.io Rust package repository
11471 @uref{https://crates.io, crates.io}, as in this example:
11474 guix import crate blake2-rfc
11477 The crate importer also allows you to specify a version string:
11480 guix import crate constant-time-eq@@0.1.0
11483 Additional options include:
11488 Traverse the dependency graph of the given upstream package recursively
11489 and generate package expressions for all those packages that are not yet
11496 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
11497 repository used by the OCaml community.
11499 Additional options include:
11504 Traverse the dependency graph of the given upstream package recursively
11505 and generate package expressions for all those packages that are not yet
11508 Select the given repository (a repository name). Possible values include:
11510 @item @code{opam}, the default opam repository,
11511 @item @code{coq} or @code{coq-released}, the stable repository for coq packages,
11512 @item @code{coq-core-dev}, the repository that contains development versions of coq,
11513 @item @code{coq-extra-dev}, the repository that contains development versions
11520 Import metadata for a Go module using
11521 @uref{https://proxy.golang.org, proxy.golang.org}.
11523 This importer is highly experimental. See the source code for more info
11524 about the current state.
11527 guix import go gopkg.in/yaml.v2
11530 Additional options include:
11535 Traverse the dependency graph of the given upstream package recursively
11536 and generate package expressions for all those packages that are not yet
11541 The structure of the @command{guix import} code is modular. It would be
11542 useful to have more importers for other package formats, and your help
11543 is welcome here (@pxref{Contributing}).
11545 @node Invoking guix refresh
11546 @section Invoking @command{guix refresh}
11548 @cindex @command {guix refresh}
11549 The primary audience of the @command{guix refresh} command is developers
11550 of the GNU software distribution. By default, it reports any packages
11551 provided by the distribution that are outdated compared to the latest
11552 upstream version, like this:
11556 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
11557 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
11560 Alternatively, one can specify packages to consider, in which case a
11561 warning is emitted for packages that lack an updater:
11564 $ guix refresh coreutils guile guile-ssh
11565 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
11566 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
11569 @command{guix refresh} browses the upstream repository of each package and determines
11570 the highest version number of the releases therein. The command
11571 knows how to update specific types of packages: GNU packages, ELPA
11572 packages, etc.---see the documentation for @option{--type} below. There
11573 are many packages, though, for which it lacks a method to determine
11574 whether a new upstream release is available. However, the mechanism is
11575 extensible, so feel free to get in touch with us to add a new method!
11580 Consider the packages specified, and all the packages upon which they depend.
11583 $ guix refresh --recursive coreutils
11584 gnu/packages/acl.scm:40:13: acl would be upgraded from 2.2.53 to 2.3.1
11585 gnu/packages/m4.scm:30:12: 1.4.18 is already the latest version of m4
11586 gnu/packages/xml.scm:68:2: warning: no updater for expat
11587 gnu/packages/multiprecision.scm:40:12: 6.1.2 is already the latest version of gmp
11593 Sometimes the upstream name differs from the package name used in Guix,
11594 and @command{guix refresh} needs a little help. Most updaters honor the
11595 @code{upstream-name} property in package definitions, which can be used
11599 (define-public network-manager
11601 (name "network-manager")
11603 (properties '((upstream-name . "NetworkManager")))))
11606 When passed @option{--update}, it modifies distribution source files to
11607 update the version numbers and source tarball hashes of those package
11608 recipes (@pxref{Defining Packages}). This is achieved by downloading
11609 each package's latest source tarball and its associated OpenPGP
11610 signature, authenticating the downloaded tarball against its signature
11611 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
11612 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
11615 key used to sign the tarball is missing from the user's keyring, an
11616 attempt is made to automatically retrieve it from a public key server;
11617 when this is successful, the key is added to the user's keyring; otherwise,
11618 @command{guix refresh} reports an error.
11620 The following options are supported:
11624 @item --expression=@var{expr}
11625 @itemx -e @var{expr}
11626 Consider the package @var{expr} evaluates to.
11628 This is useful to precisely refer to a package, as in this example:
11631 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
11634 This command lists the dependents of the ``final'' libc (essentially all
11639 Update distribution source files (package recipes) in place. This is
11640 usually run from a checkout of the Guix source tree (@pxref{Running
11641 Guix Before It Is Installed}):
11644 $ ./pre-inst-env guix refresh -s non-core -u
11647 @xref{Defining Packages}, for more information on package definitions.
11649 @item --select=[@var{subset}]
11650 @itemx -s @var{subset}
11651 Select all the packages in @var{subset}, one of @code{core} or
11654 The @code{core} subset refers to all the packages at the core of the
11655 distribution---i.e., packages that are used to build ``everything
11656 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
11657 changing one of these packages in the distribution entails a rebuild of
11658 all the others. Thus, such updates are an inconvenience to users in
11659 terms of build time or bandwidth used to achieve the upgrade.
11661 The @code{non-core} subset refers to the remaining packages. It is
11662 typically useful in cases where an update of the core packages would be
11665 @item --manifest=@var{file}
11666 @itemx -m @var{file}
11667 Select all the packages from the manifest in @var{file}. This is useful to
11668 check if any packages of the user manifest can be updated.
11670 @item --type=@var{updater}
11671 @itemx -t @var{updater}
11672 Select only packages handled by @var{updater} (may be a comma-separated
11673 list of updaters). Currently, @var{updater} may be one of:
11677 the updater for GNU packages;
11679 the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
11681 the updater for GNOME packages;
11683 the updater for KDE packages;
11685 the updater for X.org packages;
11687 the updater for packages hosted on kernel.org;
11689 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
11691 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
11693 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
11695 the updater for @uref{https://www.cpan.org/, CPAN} packages;
11697 the updater for @uref{https://pypi.python.org, PyPI} packages.
11699 the updater for @uref{https://rubygems.org, RubyGems} packages.
11701 the updater for @uref{https://github.com, GitHub} packages.
11703 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
11705 the updater for @uref{https://www.stackage.org, Stackage} packages.
11707 the updater for @uref{https://crates.io, Crates} packages.
11709 the updater for @uref{https://launchpad.net, Launchpad} packages.
11711 a generic updater that crawls the HTML page where the source tarball of
11712 the package is hosted, when applicable.
11715 For instance, the following command only checks for updates of Emacs
11716 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
11719 $ guix refresh --type=elpa,cran
11720 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
11721 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
11726 In addition, @command{guix refresh} can be passed one or more package
11727 names, as in this example:
11730 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
11734 The command above specifically updates the @code{emacs} and
11735 @code{idutils} packages. The @option{--select} option would have no
11736 effect in this case.
11738 When considering whether to upgrade a package, it is sometimes
11739 convenient to know which packages would be affected by the upgrade and
11740 should be checked for compatibility. For this the following option may
11741 be used when passing @command{guix refresh} one or more package names:
11745 @item --list-updaters
11747 List available updaters and exit (see @option{--type} above).
11749 For each updater, display the fraction of packages it covers; at the
11750 end, display the fraction of packages covered by all these updaters.
11752 @item --list-dependent
11754 List top-level dependent packages that would need to be rebuilt as a
11755 result of upgrading one or more packages.
11757 @xref{Invoking guix graph, the @code{reverse-package} type of
11758 @command{guix graph}}, for information on how to visualize the list of
11759 dependents of a package.
11763 Be aware that the @option{--list-dependent} option only
11764 @emph{approximates} the rebuilds that would be required as a result of
11765 an upgrade. More rebuilds might be required under some circumstances.
11768 $ guix refresh --list-dependent flex
11769 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
11770 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
11773 The command above lists a set of packages that could be built to check
11774 for compatibility with an upgraded @code{flex} package.
11778 @item --list-transitive
11779 List all the packages which one or more packages depend upon.
11782 $ guix refresh --list-transitive flex
11783 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
11784 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{}
11789 The command above lists a set of packages which, when changed, would cause
11790 @code{flex} to be rebuilt.
11792 The following options can be used to customize GnuPG operation:
11796 @item --gpg=@var{command}
11797 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
11798 for in @code{$PATH}.
11800 @item --keyring=@var{file}
11801 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
11802 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
11803 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
11804 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
11805 information on a tool to manipulate keybox files).
11807 When this option is omitted, @command{guix refresh} uses
11808 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
11809 signing keys. OpenPGP signatures are checked against keys from this keyring;
11810 missing keys are downloaded to this keyring as well (see
11811 @option{--key-download} below).
11813 You can export keys from your default GPG keyring into a keybox file using
11814 commands like this one:
11817 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
11820 Likewise, you can fetch keys to a specific keybox file like this:
11823 gpg --no-default-keyring --keyring mykeyring.kbx \
11824 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
11827 @xref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
11828 Privacy Guard}, for more information on GPG's @option{--keyring} option.
11830 @item --key-download=@var{policy}
11831 Handle missing OpenPGP keys according to @var{policy}, which may be one
11836 Always download missing OpenPGP keys from the key server, and add them
11837 to the user's GnuPG keyring.
11840 Never try to download missing OpenPGP keys. Instead just bail out.
11843 When a package signed with an unknown OpenPGP key is encountered, ask
11844 the user whether to download it or not. This is the default behavior.
11847 @item --key-server=@var{host}
11848 Use @var{host} as the OpenPGP key server when importing a public key.
11850 @item --load-path=@var{directory}
11851 Add @var{directory} to the front of the package module search path
11852 (@pxref{Package Modules}).
11854 This allows users to define their own packages and make them visible to
11855 the command-line tools.
11859 The @code{github} updater uses the
11860 @uref{https://developer.github.com/v3/, GitHub API} to query for new
11861 releases. When used repeatedly e.g.@: when refreshing all packages,
11862 GitHub will eventually refuse to answer any further API requests. By
11863 default 60 API requests per hour are allowed, and a full refresh on all
11864 GitHub packages in Guix requires more than this. Authentication with
11865 GitHub through the use of an API token alleviates these limits. To use
11866 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
11867 token procured from @uref{https://github.com/settings/tokens} or
11871 @node Invoking guix lint
11872 @section Invoking @command{guix lint}
11874 @cindex @command{guix lint}
11875 @cindex package, checking for errors
11876 The @command{guix lint} command is meant to help package developers avoid
11877 common errors and use a consistent style. It runs a number of checks on
11878 a given set of packages in order to find common mistakes in their
11879 definitions. Available @dfn{checkers} include (see
11880 @option{--list-checkers} for a complete list):
11885 Validate certain typographical and stylistic rules about package
11886 descriptions and synopses.
11888 @item inputs-should-be-native
11889 Identify inputs that should most likely be native inputs.
11895 @itemx source-file-name
11896 Probe @code{home-page} and @code{source} URLs and report those that are
11897 invalid. Suggest a @code{mirror://} URL when applicable. If the
11898 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
11899 URL@. Check that the source file name is meaningful, e.g.@: is not just a
11900 version number or ``git-checkout'', without a declared @code{file-name}
11901 (@pxref{origin Reference}).
11903 @item source-unstable-tarball
11904 Parse the @code{source} URL to determine if a tarball from GitHub is
11905 autogenerated or if it is a release tarball. Unfortunately GitHub's
11906 autogenerated tarballs are sometimes regenerated.
11909 Check that the derivation of the given packages can be successfully
11910 computed for all the supported systems (@pxref{Derivations}).
11912 @item profile-collisions
11913 Check whether installing the given packages in a profile would lead to
11914 collisions. Collisions occur when several packages with the same name
11915 but a different version or a different store file name are propagated.
11916 @xref{package Reference, @code{propagated-inputs}}, for more information
11917 on propagated inputs.
11920 @cindex Software Heritage, source code archive
11921 @cindex archival of source code, Software Heritage
11922 Checks whether the package's source code is archived at
11923 @uref{https://www.softwareheritage.org, Software Heritage}.
11925 When the source code that is not archived comes from a version-control system
11926 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
11927 ``save'' request so that it eventually archives it. This ensures that the
11928 source will remain available in the long term, and that Guix can fall back to
11929 Software Heritage should the source code disappear from its original host.
11930 The status of recent ``save'' requests can be
11931 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
11933 When source code is a tarball obtained with @code{url-fetch}, simply print a
11934 message when it is not archived. As of this writing, Software Heritage does
11935 not allow requests to save arbitrary tarballs; we are working on ways to
11936 ensure that non-VCS source code is also archived.
11939 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
11940 request rate per IP address}. When the limit is reached, @command{guix lint}
11941 prints a message and the @code{archival} checker stops doing anything until
11942 that limit has been reset.
11945 @cindex security vulnerabilities
11946 @cindex CVE, Common Vulnerabilities and Exposures
11947 Report known vulnerabilities found in the Common Vulnerabilities and
11948 Exposures (CVE) databases of the current and past year
11949 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
11952 To view information about a particular vulnerability, visit pages such as:
11956 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
11958 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
11962 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
11963 @code{CVE-2015-7554}.
11965 Package developers can specify in package recipes the
11966 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
11967 name and version of the package when they differ from the name or version
11968 that Guix uses, as in this example:
11974 ;; CPE calls this package "grub2".
11975 (properties '((cpe-name . "grub2")
11976 (cpe-version . "2.3"))))
11979 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
11980 Some entries in the CVE database do not specify which version of a
11981 package they apply to, and would thus ``stick around'' forever. Package
11982 developers who found CVE alerts and verified they can be ignored can
11983 declare them as in this example:
11989 ;; These CVEs no longer apply and can be safely ignored.
11990 (properties `((lint-hidden-cve . ("CVE-2011-0433"
11993 "CVE-2011-5244")))))
11997 Warn about obvious source code formatting issues: trailing white space,
11998 use of tabulations, etc.
12001 The general syntax is:
12004 guix lint @var{options} @var{package}@dots{}
12007 If no package is given on the command line, then all packages are checked.
12008 The @var{options} may be zero or more of the following:
12011 @item --list-checkers
12013 List and describe all the available checkers that will be run on packages
12018 Only enable the checkers specified in a comma-separated list using the
12019 names returned by @option{--list-checkers}.
12023 Only disable the checkers specified in a comma-separated list using the
12024 names returned by @option{--list-checkers}.
12028 Only enable the checkers that do not depend on Internet access.
12030 @item --load-path=@var{directory}
12031 @itemx -L @var{directory}
12032 Add @var{directory} to the front of the package module search path
12033 (@pxref{Package Modules}).
12035 This allows users to define their own packages and make them visible to
12036 the command-line tools.
12040 @node Invoking guix size
12041 @section Invoking @command{guix size}
12044 @cindex package size
12046 @cindex @command{guix size}
12047 The @command{guix size} command helps package developers profile the
12048 disk usage of packages. It is easy to overlook the impact of an
12049 additional dependency added to a package, or the impact of using a
12050 single output for a package that could easily be split (@pxref{Packages
12051 with Multiple Outputs}). Such are the typical issues that
12052 @command{guix size} can highlight.
12054 The command can be passed one or more package specifications
12055 such as @code{gcc@@4.8}
12056 or @code{guile:debug}, or a file name in the store. Consider this
12060 $ guix size coreutils
12061 store item total self
12062 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
12063 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
12064 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
12065 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
12066 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
12067 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
12068 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
12069 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
12074 The store items listed here constitute the @dfn{transitive closure} of
12075 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
12076 would be returned by:
12079 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
12082 Here the output shows three columns next to store items. The first column,
12083 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
12084 the store item---that is, its own size plus the size of all its
12085 dependencies. The next column, labeled ``self'', shows the size of the
12086 item itself. The last column shows the ratio of the size of the item
12087 itself to the space occupied by all the items listed here.
12089 In this example, we see that the closure of Coreutils weighs in at
12090 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
12091 libraries. (That libc and GCC's libraries represent a large fraction of
12092 the closure is not a problem @i{per se} because they are always available
12093 on the system anyway.)
12095 Since the command also accepts store file names, assessing the size of
12096 a build result is straightforward:
12099 guix size $(guix system build config.scm)
12102 When the package(s) passed to @command{guix size} are available in the
12103 store@footnote{More precisely, @command{guix size} looks for the
12104 @emph{ungrafted} variant of the given package(s), as returned by
12105 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
12106 for information on grafts.}, @command{guix size} queries the daemon to determine its
12107 dependencies, and measures its size in the store, similar to @command{du
12108 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
12111 When the given packages are @emph{not} in the store, @command{guix size}
12112 reports information based on the available substitutes
12113 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
12114 store items that are not even on disk, only available remotely.
12116 You can also specify several package names:
12119 $ guix size coreutils grep sed bash
12120 store item total self
12121 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
12122 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
12123 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
12124 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
12130 In this example we see that the combination of the four packages takes
12131 102.3@tie{}MiB in total, which is much less than the sum of each closure
12132 since they have a lot of dependencies in common.
12134 When looking at the profile returned by @command{guix size}, you may
12135 find yourself wondering why a given package shows up in the profile at
12136 all. To understand it, you can use @command{guix graph --path -t
12137 references} to display the shortest path between the two packages
12138 (@pxref{Invoking guix graph}).
12140 The available options are:
12144 @item --substitute-urls=@var{urls}
12145 Use substitute information from @var{urls}.
12146 @xref{client-substitute-urls, the same option for @code{guix build}}.
12148 @item --sort=@var{key}
12149 Sort lines according to @var{key}, one of the following options:
12153 the size of each item (the default);
12155 the total size of the item's closure.
12158 @item --map-file=@var{file}
12159 Write a graphical map of disk usage in PNG format to @var{file}.
12161 For the example above, the map looks like this:
12163 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
12164 produced by @command{guix size}}
12166 This option requires that
12167 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
12168 installed and visible in Guile's module search path. When that is not
12169 the case, @command{guix size} fails as it tries to load it.
12171 @item --system=@var{system}
12172 @itemx -s @var{system}
12173 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
12175 @item --load-path=@var{directory}
12176 @itemx -L @var{directory}
12177 Add @var{directory} to the front of the package module search path
12178 (@pxref{Package Modules}).
12180 This allows users to define their own packages and make them visible to
12181 the command-line tools.
12184 @node Invoking guix graph
12185 @section Invoking @command{guix graph}
12188 @cindex @command{guix graph}
12189 @cindex package dependencies
12190 Packages and their dependencies form a @dfn{graph}, specifically a
12191 directed acyclic graph (DAG). It can quickly become difficult to have a
12192 mental model of the package DAG, so the @command{guix graph} command
12193 provides a visual representation of the DAG@. By default,
12194 @command{guix graph} emits a DAG representation in the input format of
12195 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
12196 directly to the @command{dot} command of Graphviz. It can also emit an
12197 HTML page with embedded JavaScript code to display a ``chord diagram''
12198 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
12199 emit Cypher queries to construct a graph in a graph database supporting
12200 the @uref{https://www.opencypher.org/, openCypher} query language. With
12201 @option{--path}, it simply displays the shortest path between two
12202 packages. The general syntax is:
12205 guix graph @var{options} @var{package}@dots{}
12208 For example, the following command generates a PDF file representing the
12209 package DAG for the GNU@tie{}Core Utilities, showing its build-time
12213 guix graph coreutils | dot -Tpdf > dag.pdf
12216 The output looks like this:
12218 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
12220 Nice little graph, no?
12222 You may find it more pleasant to navigate the graph interactively with
12223 @command{xdot} (from the @code{xdot} package):
12226 guix graph coreutils | xdot -
12229 But there is more than one graph! The one above is concise: it is the
12230 graph of package objects, omitting implicit inputs such as GCC, libc,
12231 grep, etc. It is often useful to have such a concise graph, but
12232 sometimes one may want to see more details. @command{guix graph} supports
12233 several types of graphs, allowing you to choose the level of detail:
12237 This is the default type used in the example above. It shows the DAG of
12238 package objects, excluding implicit dependencies. It is concise, but
12239 filters out many details.
12241 @item reverse-package
12242 This shows the @emph{reverse} DAG of packages. For example:
12245 guix graph --type=reverse-package ocaml
12248 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
12249 you are also interested in cases where OCaml is an implicit dependency, see
12250 @code{reverse-bag} below).
12252 Note that for core packages this can yield huge graphs. If all you want
12253 is to know the number of packages that depend on a given package, use
12254 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
12255 @option{--list-dependent}}).
12258 This is the package DAG, @emph{including} implicit inputs.
12260 For instance, the following command:
12263 guix graph --type=bag-emerged coreutils
12266 ...@: yields this bigger graph:
12268 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
12270 At the bottom of the graph, we see all the implicit inputs of
12271 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
12273 Now, note that the dependencies of these implicit inputs---that is, the
12274 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
12275 here, for conciseness.
12278 Similar to @code{bag-emerged}, but this time including all the bootstrap
12281 @item bag-with-origins
12282 Similar to @code{bag}, but also showing origins and their dependencies.
12285 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
12286 it also takes implicit dependencies into account. For example:
12289 guix graph -t reverse-bag dune
12293 ...@: yields the graph of all packages that depend on Dune, directly or
12294 indirectly. Since Dune is an @emph{implicit} dependency of many packages
12295 @i{via} @code{dune-build-system}, this shows a large number of packages,
12296 whereas @code{reverse-package} would show very few if any.
12299 This is the most detailed representation: It shows the DAG of
12300 derivations (@pxref{Derivations}) and plain store items. Compared to
12301 the above representation, many additional nodes are visible, including
12302 build scripts, patches, Guile modules, etc.
12304 For this type of graph, it is also possible to pass a @file{.drv} file
12305 name instead of a package name, as in:
12308 guix graph -t derivation `guix system build -d my-config.scm`
12312 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
12313 For example, the following command shows the graph for the package
12314 module that defines the @code{guile} package:
12317 guix graph -t module guile | xdot -
12321 All the types above correspond to @emph{build-time dependencies}. The
12322 following graph type represents the @emph{run-time dependencies}:
12326 This is the graph of @dfn{references} of a package output, as returned
12327 by @command{guix gc --references} (@pxref{Invoking guix gc}).
12329 If the given package output is not available in the store, @command{guix
12330 graph} attempts to obtain dependency information from substitutes.
12332 Here you can also pass a store file name instead of a package name. For
12333 example, the command below produces the reference graph of your profile
12334 (which can be big!):
12337 guix graph -t references `readlink -f ~/.guix-profile`
12341 This is the graph of the @dfn{referrers} of a store item, as returned by
12342 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
12344 This relies exclusively on local information from your store. For
12345 instance, let us suppose that the current Inkscape is available in 10
12346 profiles on your machine; @command{guix graph -t referrers inkscape}
12347 will show a graph rooted at Inkscape and with those 10 profiles linked
12350 It can help determine what is preventing a store item from being garbage
12355 @cindex shortest path, between packages
12356 Often, the graph of the package you are interested in does not fit on
12357 your screen, and anyway all you want to know is @emph{why} that package
12358 actually depends on some seemingly unrelated package. The
12359 @option{--path} option instructs @command{guix graph} to display the
12360 shortest path between two packages (or derivations, or store items,
12364 $ guix graph --path emacs libunistring
12367 libunistring@@0.9.10
12368 $ guix graph --path -t derivation emacs libunistring
12369 /gnu/store/@dots{}-emacs-26.3.drv
12370 /gnu/store/@dots{}-mailutils-3.9.drv
12371 /gnu/store/@dots{}-libunistring-0.9.10.drv
12372 $ guix graph --path -t references emacs libunistring
12373 /gnu/store/@dots{}-emacs-26.3
12374 /gnu/store/@dots{}-libidn2-2.2.0
12375 /gnu/store/@dots{}-libunistring-0.9.10
12378 The available options are the following:
12381 @item --type=@var{type}
12382 @itemx -t @var{type}
12383 Produce a graph output of @var{type}, where @var{type} must be one of
12384 the values listed above.
12387 List the supported graph types.
12389 @item --backend=@var{backend}
12390 @itemx -b @var{backend}
12391 Produce a graph using the selected @var{backend}.
12393 @item --list-backends
12394 List the supported graph backends.
12396 Currently, the available backends are Graphviz and d3.js.
12399 Display the shortest path between two nodes of the type specified by
12400 @option{--type}. The example below shows the shortest path between
12401 @code{libreoffice} and @code{llvm} according to the references of
12402 @code{libreoffice}:
12405 $ guix graph --path -t references libreoffice llvm
12406 /gnu/store/@dots{}-libreoffice-6.4.2.2
12407 /gnu/store/@dots{}-libepoxy-1.5.4
12408 /gnu/store/@dots{}-mesa-19.3.4
12409 /gnu/store/@dots{}-llvm-9.0.1
12412 @item --expression=@var{expr}
12413 @itemx -e @var{expr}
12414 Consider the package @var{expr} evaluates to.
12416 This is useful to precisely refer to a package, as in this example:
12419 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
12422 @item --system=@var{system}
12423 @itemx -s @var{system}
12424 Display the graph for @var{system}---e.g., @code{i686-linux}.
12426 The package dependency graph is largely architecture-independent, but there
12427 are some architecture-dependent bits that this option allows you to visualize.
12429 @item --load-path=@var{directory}
12430 @itemx -L @var{directory}
12431 Add @var{directory} to the front of the package module search path
12432 (@pxref{Package Modules}).
12434 This allows users to define their own packages and make them visible to
12435 the command-line tools.
12438 On top of that, @command{guix graph} supports all the usual package
12439 transformation options (@pxref{Package Transformation Options}). This
12440 makes it easy to view the effect of a graph-rewriting transformation
12441 such as @option{--with-input}. For example, the command below outputs
12442 the graph of @code{git} once @code{openssl} has been replaced by
12443 @code{libressl} everywhere in the graph:
12446 guix graph git --with-input=openssl=libressl
12449 So many possibilities, so much fun!
12451 @node Invoking guix publish
12452 @section Invoking @command{guix publish}
12454 @cindex @command{guix publish}
12455 The purpose of @command{guix publish} is to enable users to easily share
12456 their store with others, who can then use it as a substitute server
12457 (@pxref{Substitutes}).
12459 When @command{guix publish} runs, it spawns an HTTP server which allows
12460 anyone with network access to obtain substitutes from it. This means
12461 that any machine running Guix can also act as if it were a build farm,
12462 since the HTTP interface is compatible with Cuirass, the software behind
12463 the @code{@value{SUBSTITUTE-SERVER}} build farm.
12465 For security, each substitute is signed, allowing recipients to check
12466 their authenticity and integrity (@pxref{Substitutes}). Because
12467 @command{guix publish} uses the signing key of the system, which is only
12468 readable by the system administrator, it must be started as root; the
12469 @option{--user} option makes it drop root privileges early on.
12471 The signing key pair must be generated before @command{guix publish} is
12472 launched, using @command{guix archive --generate-key} (@pxref{Invoking
12475 When the @option{--advertise} option is passed, the server advertises
12476 its availability on the local network using multicast DNS (mDNS) and DNS
12477 service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
12478 guile-avahi, Using Avahi in Guile Scheme Programs}).
12480 The general syntax is:
12483 guix publish @var{options}@dots{}
12486 Running @command{guix publish} without any additional arguments will
12487 spawn an HTTP server on port 8080:
12493 Once a publishing server has been authorized, the daemon may download
12494 substitutes from it. @xref{Getting Substitutes from Other Servers}.
12496 By default, @command{guix publish} compresses archives on the fly as it
12497 serves them. This ``on-the-fly'' mode is convenient in that it requires
12498 no setup and is immediately available. However, when serving lots of
12499 clients, we recommend using the @option{--cache} option, which enables
12500 caching of the archives before they are sent to clients---see below for
12501 details. The @command{guix weather} command provides a handy way to
12502 check what a server provides (@pxref{Invoking guix weather}).
12504 As a bonus, @command{guix publish} also serves as a content-addressed
12505 mirror for source files referenced in @code{origin} records
12506 (@pxref{origin Reference}). For instance, assuming @command{guix
12507 publish} is running on @code{example.org}, the following URL returns the
12508 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
12509 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
12512 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
12515 Obviously, these URLs only work for files that are in the store; in
12516 other cases, they return 404 (``Not Found'').
12518 @cindex build logs, publication
12519 Build logs are available from @code{/log} URLs like:
12522 http://example.org/log/gwspk@dots{}-guile-2.2.3
12526 When @command{guix-daemon} is configured to save compressed build logs,
12527 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
12528 URLs return the compressed log as-is, with an appropriate
12529 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
12530 running @command{guix-daemon} with @option{--log-compression=gzip} since
12531 Web browsers can automatically decompress it, which is not the case with
12534 The following options are available:
12537 @item --port=@var{port}
12538 @itemx -p @var{port}
12539 Listen for HTTP requests on @var{port}.
12541 @item --listen=@var{host}
12542 Listen on the network interface for @var{host}. The default is to
12543 accept connections from any interface.
12545 @item --user=@var{user}
12546 @itemx -u @var{user}
12547 Change privileges to @var{user} as soon as possible---i.e., once the
12548 server socket is open and the signing key has been read.
12550 @item --compression[=@var{method}[:@var{level}]]
12551 @itemx -C [@var{method}[:@var{level}]]
12552 Compress data using the given @var{method} and @var{level}. @var{method} is
12553 one of @code{lzip}, @code{zstd}, and @code{gzip}; when @var{method} is
12554 omitted, @code{gzip} is used.
12556 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
12557 to different compression levels: 1 is the fastest, and 9 is the best
12558 (CPU-intensive). The default is 3.
12560 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a
12561 small increase in CPU usage; see
12562 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip
12563 Web page}. However, @code{lzip} achieves low decompression throughput
12564 (on the order of 50@tie{}MiB/s on modern hardware), which can be a
12565 bottleneck for someone who downloads over a fast network connection.
12567 The compression ratio of @code{zstd} is between that of @code{lzip} and
12568 that of @code{gzip}; its main advantage is a
12569 @uref{https://facebook.github.io/zstd/,high decompression speed}.
12571 Unless @option{--cache} is used, compression occurs on the fly and
12572 the compressed streams are not
12573 cached. Thus, to reduce load on the machine that runs @command{guix
12574 publish}, it may be a good idea to choose a low compression level, to
12575 run @command{guix publish} behind a caching proxy, or to use
12576 @option{--cache}. Using @option{--cache} has the advantage that it
12577 allows @command{guix publish} to add @code{Content-Length} HTTP header
12580 This option can be repeated, in which case every substitute gets compressed
12581 using all the selected methods, and all of them are advertised. This is
12582 useful when users may not support all the compression methods: they can select
12583 the one they support.
12585 @item --cache=@var{directory}
12586 @itemx -c @var{directory}
12587 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
12588 and only serve archives that are in cache.
12590 When this option is omitted, archives and meta-data are created
12591 on-the-fly. This can reduce the available bandwidth, especially when
12592 compression is enabled, since this may become CPU-bound. Another
12593 drawback of the default mode is that the length of archives is not known
12594 in advance, so @command{guix publish} does not add a
12595 @code{Content-Length} HTTP header to its responses, which in turn
12596 prevents clients from knowing the amount of data being downloaded.
12598 Conversely, when @option{--cache} is used, the first request for a store
12599 item (@i{via} a @code{.narinfo} URL) triggers a
12600 background process to @dfn{bake} the archive---computing its
12601 @code{.narinfo} and compressing the archive, if needed. Once the
12602 archive is cached in @var{directory}, subsequent requests succeed and
12603 are served directly from the cache, which guarantees that clients get
12604 the best possible bandwidth.
12606 That first @code{.narinfo} request nonetheless returns 200, provided the
12607 requested store item is ``small enough'', below the cache bypass
12608 threshold---see @option{--cache-bypass-threshold} below. That way,
12609 clients do not have to wait until the archive is baked. For larger
12610 store items, the first @code{.narinfo} request returns 404, meaning that
12611 clients have to wait until the archive is baked.
12613 The ``baking'' process is performed by worker threads. By default, one
12614 thread per CPU core is created, but this can be customized. See
12615 @option{--workers} below.
12617 When @option{--ttl} is used, cached entries are automatically deleted
12618 when they have expired.
12620 @item --workers=@var{N}
12621 When @option{--cache} is used, request the allocation of @var{N} worker
12622 threads to ``bake'' archives.
12624 @item --ttl=@var{ttl}
12625 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
12626 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
12627 days, @code{1m} means 1 month, and so on.
12629 This allows the user's Guix to keep substitute information in cache for
12630 @var{ttl}. However, note that @code{guix publish} does not itself
12631 guarantee that the store items it provides will indeed remain available
12632 for as long as @var{ttl}.
12634 Additionally, when @option{--cache} is used, cached entries that have
12635 not been accessed for @var{ttl} and that no longer have a corresponding
12636 item in the store, may be deleted.
12638 @item --cache-bypass-threshold=@var{size}
12639 When used in conjunction with @option{--cache}, store items smaller than
12640 @var{size} are immediately available, even when they are not yet in
12641 cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
12642 for megabytes and so on. The default is @code{10M}.
12644 ``Cache bypass'' allows you to reduce the publication delay for clients
12645 at the expense of possibly additional I/O and CPU use on the server
12646 side: depending on the client access patterns, those store items can end
12647 up being baked several times until a copy is available in cache.
12649 Increasing the threshold may be useful for sites that have few users, or
12650 to guarantee that users get substitutes even for store items that are
12653 @item --nar-path=@var{path}
12654 Use @var{path} as the prefix for the URLs of ``nar'' files
12655 (@pxref{Invoking guix archive, normalized archives}).
12657 By default, nars are served at a URL such as
12658 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
12659 change the @code{/nar} part to @var{path}.
12661 @item --public-key=@var{file}
12662 @itemx --private-key=@var{file}
12663 Use the specific @var{file}s as the public/private key pair used to sign
12664 the store items being published.
12666 The files must correspond to the same key pair (the private key is used
12667 for signing and the public key is merely advertised in the signature
12668 metadata). They must contain keys in the canonical s-expression format
12669 as produced by @command{guix archive --generate-key} (@pxref{Invoking
12670 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
12671 @file{/etc/guix/signing-key.sec} are used.
12673 @item --repl[=@var{port}]
12674 @itemx -r [@var{port}]
12675 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
12676 Reference Manual}) on @var{port} (37146 by default). This is used
12677 primarily for debugging a running @command{guix publish} server.
12680 Enabling @command{guix publish} on Guix System is a one-liner: just
12681 instantiate a @code{guix-publish-service-type} service in the @code{services} field
12682 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
12683 @code{guix-publish-service-type}}).
12685 If you are instead running Guix on a ``foreign distro'', follow these
12690 If your host distro uses the systemd init system:
12693 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
12694 /etc/systemd/system/
12695 # systemctl start guix-publish && systemctl enable guix-publish
12699 If your host distro uses the Upstart init system:
12702 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
12703 # start guix-publish
12707 Otherwise, proceed similarly with your distro's init system.
12710 @node Invoking guix challenge
12711 @section Invoking @command{guix challenge}
12713 @cindex reproducible builds
12714 @cindex verifiable builds
12715 @cindex @command{guix challenge}
12717 Do the binaries provided by this server really correspond to the source
12718 code it claims to build? Is a package build process deterministic?
12719 These are the questions the @command{guix challenge} command attempts to
12722 The former is obviously an important question: Before using a substitute
12723 server (@pxref{Substitutes}), one had better @emph{verify} that it
12724 provides the right binaries, and thus @emph{challenge} it. The latter
12725 is what enables the former: If package builds are deterministic, then
12726 independent builds of the package should yield the exact same result,
12727 bit for bit; if a server provides a binary different from the one
12728 obtained locally, it may be either corrupt or malicious.
12730 We know that the hash that shows up in @file{/gnu/store} file names is
12731 the hash of all the inputs of the process that built the file or
12732 directory---compilers, libraries, build scripts,
12733 etc. (@pxref{Introduction}). Assuming deterministic build processes,
12734 one store file name should map to exactly one build output.
12735 @command{guix challenge} checks whether there is, indeed, a single
12736 mapping by comparing the build outputs of several independent builds of
12737 any given store item.
12739 The command output looks like this:
12742 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
12743 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
12744 updating list of substitutes from 'https://guix.example.org'... 100.0%
12745 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
12746 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
12747 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
12748 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
12750 /lib/libcrypto.so.1.1
12753 /gnu/store/@dots{}-git-2.5.0 contents differ:
12754 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
12755 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
12756 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
12758 /libexec/git-core/git-fsck
12760 /gnu/store/@dots{}-pius-2.1.1 contents differ:
12761 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
12762 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
12763 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
12765 /share/man/man1/pius.1.gz
12769 6,406 store items were analyzed:
12770 - 4,749 (74.1%) were identical
12771 - 525 (8.2%) differed
12772 - 1,132 (17.7%) were inconclusive
12776 In this example, @command{guix challenge} first scans the store to
12777 determine the set of locally-built derivations---as opposed to store
12778 items that were downloaded from a substitute server---and then queries
12779 all the substitute servers. It then reports those store items for which
12780 the servers obtained a result different from the local build.
12782 @cindex non-determinism, in package builds
12783 As an example, @code{guix.example.org} always gets a different answer.
12784 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
12785 case of Git. This might indicate that the build process of Git is
12786 non-deterministic, meaning that its output varies as a function of
12787 various things that Guix does not fully control, in spite of building
12788 packages in isolated environments (@pxref{Features}). Most common
12789 sources of non-determinism include the addition of timestamps in build
12790 results, the inclusion of random numbers, and directory listings sorted
12791 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
12794 To find out what is wrong with this Git binary, the easiest approach is
12798 guix challenge git \
12799 --diff=diffoscope \
12800 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
12803 This automatically invokes @command{diffoscope}, which displays detailed
12804 information about files that differ.
12806 Alternatively, we can do something along these lines (@pxref{Invoking guix
12810 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-git-2.5.0 \
12811 | lzip -d | guix archive -x /tmp/git
12812 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
12815 This command shows the difference between the files resulting from the
12816 local build, and the files resulting from the build on
12817 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
12818 diffutils, Comparing and Merging Files}). The @command{diff} command
12819 works great for text files. When binary files differ, a better option
12820 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
12821 visualize differences for all kinds of files.
12823 Once you have done that work, you can tell whether the differences are due
12824 to a non-deterministic build process or to a malicious server. We try
12825 hard to remove sources of non-determinism in packages to make it easier
12826 to verify substitutes, but of course, this is a process that
12827 involves not just Guix, but a large part of the free software community.
12828 In the meantime, @command{guix challenge} is one tool to help address
12831 If you are writing packages for Guix, you are encouraged to check
12832 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
12833 same build result as you did with:
12836 $ guix challenge @var{package}
12840 where @var{package} is a package specification such as
12841 @code{guile@@2.0} or @code{glibc:debug}.
12843 The general syntax is:
12846 guix challenge @var{options} [@var{packages}@dots{}]
12849 When a difference is found between the hash of a locally-built item and
12850 that of a server-provided substitute, or among substitutes provided by
12851 different servers, the command displays it as in the example above and
12852 its exit code is 2 (other non-zero exit codes denote other kinds of
12855 The one option that matters is:
12859 @item --substitute-urls=@var{urls}
12860 Consider @var{urls} the whitespace-separated list of substitute source
12861 URLs to compare to.
12863 @item --diff=@var{mode}
12864 Upon mismatches, show differences according to @var{mode}, one of:
12867 @item @code{simple} (the default)
12868 Show the list of files that differ.
12870 @item @code{diffoscope}
12871 @itemx @var{command}
12872 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
12873 two directories whose contents do not match.
12875 When @var{command} is an absolute file name, run @var{command} instead
12879 Do not show further details about the differences.
12882 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
12883 downloads the store items from the given substitute servers so that it
12888 Show details about matches (identical contents) in addition to
12889 information about mismatches.
12893 @node Invoking guix copy
12894 @section Invoking @command{guix copy}
12896 @cindex copy, of store items, over SSH
12897 @cindex SSH, copy of store items
12898 @cindex sharing store items across machines
12899 @cindex transferring store items across machines
12900 The @command{guix copy} command copies items from the store of one
12901 machine to that of another machine over a secure shell (SSH)
12902 connection@footnote{This command is available only when Guile-SSH was
12903 found. @xref{Requirements}, for details.}. For example, the following
12904 command copies the @code{coreutils} package, the user's profile, and all
12905 their dependencies over to @var{host}, logged in as @var{user}:
12908 guix copy --to=@var{user}@@@var{host} \
12909 coreutils `readlink -f ~/.guix-profile`
12912 If some of the items to be copied are already present on @var{host},
12913 they are not actually sent.
12915 The command below retrieves @code{libreoffice} and @code{gimp} from
12916 @var{host}, assuming they are available there:
12919 guix copy --from=@var{host} libreoffice gimp
12922 The SSH connection is established using the Guile-SSH client, which is
12923 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
12924 @file{~/.ssh/config}, and uses the SSH agent for authentication.
12926 The key used to sign items that are sent must be accepted by the remote
12927 machine. Likewise, the key used by the remote machine to sign items you
12928 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
12929 own daemon. @xref{Invoking guix archive}, for more information about
12930 store item authentication.
12932 The general syntax is:
12935 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
12938 You must always specify one of the following options:
12941 @item --to=@var{spec}
12942 @itemx --from=@var{spec}
12943 Specify the host to send to or receive from. @var{spec} must be an SSH
12944 spec such as @code{example.org}, @code{charlie@@example.org}, or
12945 @code{charlie@@example.org:2222}.
12948 The @var{items} can be either package names, such as @code{gimp}, or
12949 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
12951 When specifying the name of a package to send, it is first built if
12952 needed, unless @option{--dry-run} was specified. Common build options
12953 are supported (@pxref{Common Build Options}).
12956 @node Invoking guix container
12957 @section Invoking @command{guix container}
12959 @cindex @command{guix container}
12961 As of version @value{VERSION}, this tool is experimental. The interface
12962 is subject to radical change in the future.
12965 The purpose of @command{guix container} is to manipulate processes
12966 running within an isolated environment, commonly known as a
12967 ``container'', typically created by the @command{guix environment}
12968 (@pxref{Invoking guix environment}) and @command{guix system container}
12969 (@pxref{Invoking guix system}) commands.
12971 The general syntax is:
12974 guix container @var{action} @var{options}@dots{}
12977 @var{action} specifies the operation to perform with a container, and
12978 @var{options} specifies the context-specific arguments for the action.
12980 The following actions are available:
12984 Execute a command within the context of a running container.
12989 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
12992 @var{pid} specifies the process ID of the running container.
12993 @var{program} specifies an executable file name within the root file
12994 system of the container. @var{arguments} are the additional options that
12995 will be passed to @var{program}.
12997 The following command launches an interactive login shell inside a
12998 Guix system container, started by @command{guix system container}, and whose
12999 process ID is 9001:
13002 guix container exec 9001 /run/current-system/profile/bin/bash --login
13005 Note that the @var{pid} cannot be the parent process of a container. It
13006 must be PID 1 of the container or one of its child processes.
13010 @node Invoking guix weather
13011 @section Invoking @command{guix weather}
13013 Occasionally you're grumpy because substitutes are lacking and you end
13014 up building packages by yourself (@pxref{Substitutes}). The
13015 @command{guix weather} command reports on substitute availability on the
13016 specified servers so you can have an idea of whether you'll be grumpy
13017 today. It can sometimes be useful info as a user, but it is primarily
13018 useful to people running @command{guix publish} (@pxref{Invoking guix
13021 @cindex statistics, for substitutes
13022 @cindex availability of substitutes
13023 @cindex substitute availability
13024 @cindex weather, substitute availability
13025 Here's a sample run:
13028 $ guix weather --substitute-urls=https://guix.example.org
13029 computing 5,872 package derivations for x86_64-linux...
13030 looking for 6,128 store items on https://guix.example.org..
13031 updating list of substitutes from 'https://guix.example.org'... 100.0%
13032 https://guix.example.org
13033 43.4% substitutes available (2,658 out of 6,128)
13034 7,032.5 MiB of nars (compressed)
13035 19,824.2 MiB on disk (uncompressed)
13036 0.030 seconds per request (182.9 seconds in total)
13037 33.5 requests per second
13039 9.8% (342 out of 3,470) of the missing items are queued
13041 x86_64-linux: 518 (59.7%)
13042 i686-linux: 221 (25.5%)
13043 aarch64-linux: 128 (14.8%)
13044 build rate: 23.41 builds per hour
13045 x86_64-linux: 11.16 builds per hour
13046 i686-linux: 6.03 builds per hour
13047 aarch64-linux: 6.41 builds per hour
13050 @cindex continuous integration, statistics
13051 As you can see, it reports the fraction of all the packages for which
13052 substitutes are available on the server---regardless of whether
13053 substitutes are enabled, and regardless of whether this server's signing
13054 key is authorized. It also reports the size of the compressed archives
13055 (``nars'') provided by the server, the size the corresponding store
13056 items occupy in the store (assuming deduplication is turned off), and
13057 the server's throughput. The second part gives continuous integration
13058 (CI) statistics, if the server supports it. In addition, using the
13059 @option{--coverage} option, @command{guix weather} can list ``important''
13060 package substitutes missing on the server (see below).
13062 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
13063 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
13064 challenge}, it ignores signatures on those substitutes, which is
13065 innocuous since the command only gathers statistics and cannot install
13068 The general syntax is:
13071 guix weather @var{options}@dots{} [@var{packages}@dots{}]
13074 When @var{packages} is omitted, @command{guix weather} checks the availability
13075 of substitutes for @emph{all} the packages, or for those specified with
13076 @option{--manifest}; otherwise it only considers the specified packages. It
13077 is also possible to query specific system types with @option{--system}.
13078 @command{guix weather} exits with a non-zero code when the fraction of
13079 available substitutes is below 100%.
13081 The available options are listed below.
13084 @item --substitute-urls=@var{urls}
13085 @var{urls} is the space-separated list of substitute server URLs to
13086 query. When this option is omitted, the default set of substitute
13087 servers is queried.
13089 @item --system=@var{system}
13090 @itemx -s @var{system}
13091 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
13092 option can be repeated, in which case @command{guix weather} will query
13093 substitutes for several system types.
13095 @item --manifest=@var{file}
13096 Instead of querying substitutes for all the packages, only ask for those
13097 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
13098 with the @code{-m} option of @command{guix package} (@pxref{Invoking
13101 This option can be repeated several times, in which case the manifests
13104 @item --coverage[=@var{count}]
13105 @itemx -c [@var{count}]
13106 Report on substitute coverage for packages: list packages with at least
13107 @var{count} dependents (zero by default) for which substitutes are
13108 unavailable. Dependent packages themselves are not listed: if @var{b} depends
13109 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
13110 @var{b} usually lacks substitutes as well. The result looks like this:
13113 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
13114 computing 8,983 package derivations for x86_64-linux...
13115 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
13116 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
13117 @value{SUBSTITUTE-URL}
13118 64.7% substitutes available (6,047 out of 9,343)
13120 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
13121 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
13122 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
13123 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
13127 What this example shows is that @code{kcoreaddons} and presumably the 58
13128 packages that depend on it have no substitutes at
13129 @code{@value{SUBSTITUTE-SERVER}}; likewise for @code{qgpgme} and the 46
13130 packages that depend on it.
13132 If you are a Guix developer, or if you are taking care of this build farm,
13133 you'll probably want to have a closer look at these packages: they may simply
13136 @item --display-missing
13137 Display the list of store items for which substitutes are missing.
13140 @node Invoking guix processes
13141 @section Invoking @command{guix processes}
13143 The @command{guix processes} command can be useful to developers and system
13144 administrators, especially on multi-user machines and on build farms: it lists
13145 the current sessions (connections to the daemon), as well as information about
13146 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
13147 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
13148 listed.}. Here's an example of the information it returns:
13151 $ sudo guix processes
13154 ClientCommand: guix environment --ad-hoc python
13158 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
13162 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
13163 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
13164 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
13165 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
13167 ChildCommand: guix offload x86_64-linux 7200 1 28800
13169 ChildCommand: guix offload x86_64-linux 7200 1 28800
13171 ChildCommand: guix offload x86_64-linux 7200 1 28800
13174 In this example we see that @command{guix-daemon} has three clients:
13175 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
13176 integration tool; their process identifier (PID) is given by the
13177 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
13178 @command{guix-daemon} sub-process of this particular session.
13180 The @code{LockHeld} fields show which store items are currently locked
13181 by this session, which corresponds to store items being built or
13182 substituted (the @code{LockHeld} field is not displayed when
13183 @command{guix processes} is not running as root). Last, by looking at
13184 the @code{ChildPID} and @code{ChildCommand} fields, we understand that
13185 these three builds are being offloaded (@pxref{Daemon Offload Setup}).
13187 The output is in Recutils format so we can use the handy @command{recsel}
13188 command to select sessions of interest (@pxref{Selection Expressions,,,
13189 recutils, GNU recutils manual}). As an example, the command shows the command
13190 line and PID of the client that triggered the build of a Perl package:
13193 $ sudo guix processes | \
13194 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
13196 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
13199 Additional options are listed below.
13202 @item --format=@var{format}
13203 @itemx -f @var{format}
13204 Produce output in the specified @var{format}, one of:
13208 The default option. It outputs a set of Session recutils records
13209 that include each @code{ChildProcess} as a field.
13212 Normalize the output records into record sets (@pxref{Record Sets,,,
13213 recutils, GNU recutils manual}). Normalizing into record sets allows
13214 joins across record types. The example below lists the PID of each
13215 @code{ChildProcess} and the associated PID for @code{Session} that
13216 spawned the @code{ChildProcess} where the @code{Session} was started
13217 using @command{guix build}.
13220 $ guix processes --format=normalized | \
13224 -p Session.PID,PID \
13225 -e 'Session.ClientCommand ~ "guix build"'
13238 @node System Configuration
13239 @chapter System Configuration
13241 @cindex system configuration
13242 Guix System supports a consistent whole-system configuration
13243 mechanism. By that we mean that all aspects of the global system
13244 configuration---such as the available system services, timezone and
13245 locale settings, user accounts---are declared in a single place. Such
13246 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
13248 One of the advantages of putting all the system configuration under the
13249 control of Guix is that it supports transactional system upgrades, and
13250 makes it possible to roll back to a previous system instantiation,
13251 should something go wrong with the new one (@pxref{Features}). Another
13252 advantage is that it makes it easy to replicate the exact same configuration
13253 across different machines, or at different points in time, without
13254 having to resort to additional administration tools layered on top of
13255 the own tools of the system.
13256 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
13258 This section describes this mechanism. First we focus on the system
13259 administrator's viewpoint---explaining how the system is configured and
13260 instantiated. Then we show how this mechanism can be extended, for
13261 instance to support new system services.
13264 * Using the Configuration System:: Customizing your GNU system.
13265 * operating-system Reference:: Detail of operating-system declarations.
13266 * File Systems:: Configuring file system mounts.
13267 * Mapped Devices:: Block device extra processing.
13268 * User Accounts:: Specifying user accounts.
13269 * Keyboard Layout:: How the system interprets key strokes.
13270 * Locales:: Language and cultural convention settings.
13271 * Services:: Specifying system services.
13272 * Setuid Programs:: Programs running with root privileges.
13273 * X.509 Certificates:: Authenticating HTTPS servers.
13274 * Name Service Switch:: Configuring libc's name service switch.
13275 * Initial RAM Disk:: Linux-Libre bootstrapping.
13276 * Bootloader Configuration:: Configuring the boot loader.
13277 * Invoking guix system:: Instantiating a system configuration.
13278 * Invoking guix deploy:: Deploying a system configuration to a remote host.
13279 * Running Guix in a VM:: How to run Guix System in a virtual machine.
13280 * Defining Services:: Adding new service definitions.
13283 @node Using the Configuration System
13284 @section Using the Configuration System
13286 The operating system is configured by providing an
13287 @code{operating-system} declaration in a file that can then be passed to
13288 the @command{guix system} command (@pxref{Invoking guix system}). A
13289 simple setup, with the default system services, the default Linux-Libre
13290 kernel, initial RAM disk, and boot loader looks like this:
13292 @findex operating-system
13294 @include os-config-bare-bones.texi
13297 This example should be self-describing. Some of the fields defined
13298 above, such as @code{host-name} and @code{bootloader}, are mandatory.
13299 Others, such as @code{packages} and @code{services}, can be omitted, in
13300 which case they get a default value.
13302 Below we discuss the effect of some of the most important fields
13303 (@pxref{operating-system Reference}, for details about all the available
13304 fields), and how to @dfn{instantiate} the operating system using
13305 @command{guix system}.
13307 @unnumberedsubsec Bootloader
13309 @cindex legacy boot, on Intel machines
13310 @cindex BIOS boot, on Intel machines
13313 The @code{bootloader} field describes the method that will be used to boot
13314 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
13315 mode, as in the example above. However, more recent machines rely instead on
13316 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
13317 the @code{bootloader} field should contain something along these lines:
13320 (bootloader-configuration
13321 (bootloader grub-efi-bootloader)
13322 (target "/boot/efi"))
13325 @xref{Bootloader Configuration}, for more information on the available
13326 configuration options.
13328 @unnumberedsubsec Globally-Visible Packages
13330 @vindex %base-packages
13331 The @code{packages} field lists packages that will be globally visible
13332 on the system, for all user accounts---i.e., in every user's @env{PATH}
13333 environment variable---in addition to the per-user profiles
13334 (@pxref{Invoking guix package}). The @code{%base-packages} variable
13335 provides all the tools one would expect for basic user and administrator
13336 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
13337 the GNU Zile lightweight text editor, @command{find}, @command{grep},
13338 etc. The example above adds GNU@tie{}Screen to those,
13339 taken from the @code{(gnu packages screen)}
13340 module (@pxref{Package Modules}). The
13341 @code{(list package output)} syntax can be used to add a specific output
13345 (use-modules (gnu packages))
13346 (use-modules (gnu packages dns))
13350 (packages (cons (list bind "utils")
13354 @findex specification->package
13355 Referring to packages by variable name, like @code{bind} above, has
13356 the advantage of being unambiguous; it also allows typos and such to be
13357 diagnosed right away as ``unbound variables''. The downside is that one
13358 needs to know which module defines which package, and to augment the
13359 @code{use-package-modules} line accordingly. To avoid that, one can use
13360 the @code{specification->package} procedure of the @code{(gnu packages)}
13361 module, which returns the best package for a given name or name and
13365 (use-modules (gnu packages))
13369 (packages (append (map specification->package
13370 '("tcpdump" "htop" "gnupg@@2.0"))
13374 @unnumberedsubsec System Services
13377 @vindex %base-services
13378 The @code{services} field lists @dfn{system services} to be made
13379 available when the system starts (@pxref{Services}).
13380 The @code{operating-system} declaration above specifies that, in
13381 addition to the basic services, we want the OpenSSH secure shell
13382 daemon listening on port 2222 (@pxref{Networking Services,
13383 @code{openssh-service-type}}). Under the hood,
13384 @code{openssh-service-type} arranges so that @command{sshd} is started with the
13385 right command-line options, possibly with supporting configuration files
13386 generated as needed (@pxref{Defining Services}).
13388 @cindex customization, of services
13389 @findex modify-services
13390 Occasionally, instead of using the base services as is, you will want to
13391 customize them. To do this, use @code{modify-services} (@pxref{Service
13392 Reference, @code{modify-services}}) to modify the list.
13394 For example, suppose you want to modify @code{guix-daemon} and Mingetty
13395 (the console log-in) in the @code{%base-services} list (@pxref{Base
13396 Services, @code{%base-services}}). To do that, you can write the
13397 following in your operating system declaration:
13400 (define %my-services
13401 ;; My very own list of services.
13402 (modify-services %base-services
13403 (guix-service-type config =>
13404 (guix-configuration
13406 ;; Fetch substitutes from example.org.
13408 (list "https://example.org/guix"
13409 "https://ci.guix.gnu.org"))))
13410 (mingetty-service-type config =>
13411 (mingetty-configuration
13413 ;; Automatially log in as "guest".
13414 (auto-login "guest")))))
13418 (services %my-services))
13421 This changes the configuration---i.e., the service parameters---of the
13422 @code{guix-service-type} instance, and that of all the
13423 @code{mingetty-service-type} instances in the @code{%base-services} list.
13424 Observe how this is accomplished: first, we arrange for the original
13425 configuration to be bound to the identifier @code{config} in the
13426 @var{body}, and then we write the @var{body} so that it evaluates to the
13427 desired configuration. In particular, notice how we use @code{inherit}
13428 to create a new configuration which has the same values as the old
13429 configuration, but with a few modifications.
13431 @cindex encrypted disk
13432 The configuration for a typical ``desktop'' usage, with an encrypted
13433 root partition, the X11 display
13434 server, GNOME and Xfce (users can choose which of these desktop
13435 environments to use at the log-in screen by pressing @kbd{F1}), network
13436 management, power management, and more, would look like this:
13439 @include os-config-desktop.texi
13442 A graphical system with a choice of lightweight window managers
13443 instead of full-blown desktop environments would look like this:
13446 @include os-config-lightweight-desktop.texi
13449 This example refers to the @file{/boot/efi} file system by its UUID,
13450 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
13451 as returned by the @command{blkid} command.
13453 @xref{Desktop Services}, for the exact list of services provided by
13454 @code{%desktop-services}. @xref{X.509 Certificates}, for background
13455 information about the @code{nss-certs} package that is used here.
13457 Again, @code{%desktop-services} is just a list of service objects. If
13458 you want to remove services from there, you can do so using the
13459 procedures for list filtering (@pxref{SRFI-1 Filtering and
13460 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
13461 following expression returns a list that contains all the services in
13462 @code{%desktop-services} minus the Avahi service:
13465 (remove (lambda (service)
13466 (eq? (service-kind service) avahi-service-type))
13470 @unnumberedsubsec Instantiating the System
13472 Assuming the @code{operating-system} declaration
13473 is stored in the @file{my-system-config.scm}
13474 file, the @command{guix system reconfigure my-system-config.scm} command
13475 instantiates that configuration, and makes it the default GRUB boot
13476 entry (@pxref{Invoking guix system}).
13478 The normal way to change the system configuration is by updating this
13479 file and re-running @command{guix system reconfigure}. One should never
13480 have to touch files in @file{/etc} or to run commands that modify the
13481 system state such as @command{useradd} or @command{grub-install}. In
13482 fact, you must avoid that since that would not only void your warranty
13483 but also prevent you from rolling back to previous versions of your
13484 system, should you ever need to.
13486 @cindex roll-back, of the operating system
13487 Speaking of roll-back, each time you run @command{guix system
13488 reconfigure}, a new @dfn{generation} of the system is created---without
13489 modifying or deleting previous generations. Old system generations get
13490 an entry in the bootloader boot menu, allowing you to boot them in case
13491 something went wrong with the latest generation. Reassuring, no? The
13492 @command{guix system list-generations} command lists the system
13493 generations available on disk. It is also possible to roll back the
13494 system via the commands @command{guix system roll-back} and
13495 @command{guix system switch-generation}.
13497 Although the @command{guix system reconfigure} command will not modify
13498 previous generations, you must take care when the current generation is not
13499 the latest (e.g., after invoking @command{guix system roll-back}), since
13500 the operation might overwrite a later generation (@pxref{Invoking guix
13503 @unnumberedsubsec The Programming Interface
13505 At the Scheme level, the bulk of an @code{operating-system} declaration
13506 is instantiated with the following monadic procedure (@pxref{The Store
13509 @deffn {Monadic Procedure} operating-system-derivation os
13510 Return a derivation that builds @var{os}, an @code{operating-system}
13511 object (@pxref{Derivations}).
13513 The output of the derivation is a single directory that refers to all
13514 the packages, configuration files, and other supporting files needed to
13515 instantiate @var{os}.
13518 This procedure is provided by the @code{(gnu system)} module. Along
13519 with @code{(gnu services)} (@pxref{Services}), this module contains the
13520 guts of Guix System. Make sure to visit it!
13523 @node operating-system Reference
13524 @section @code{operating-system} Reference
13526 This section summarizes all the options available in
13527 @code{operating-system} declarations (@pxref{Using the Configuration
13530 @deftp {Data Type} operating-system
13531 This is the data type representing an operating system configuration.
13532 By that, we mean all the global system configuration, not per-user
13533 configuration (@pxref{Using the Configuration System}).
13536 @item @code{kernel} (default: @code{linux-libre})
13537 The package object of the operating system kernel to
13538 use@footnote{Currently only the Linux-libre kernel is fully supported.
13539 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
13540 available when building a virtual machine disk image.}.
13543 @item @code{hurd} (default: @code{#f})
13544 The package object of the Hurd to be started by the kernel. When this
13545 field is set, produce a GNU/Hurd operating system. In that case,
13546 @code{kernel} must also be set to the @code{gnumach} package---the
13547 microkernel the Hurd runs on.
13550 This feature is experimental and only supported for disk images.
13553 @item @code{kernel-loadable-modules} (default: '())
13554 A list of objects (usually packages) to collect loadable kernel modules
13555 from--e.g. @code{(list ddcci-driver-linux)}.
13557 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
13558 List of strings or gexps representing additional arguments to pass on
13559 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
13561 @item @code{bootloader}
13562 The system bootloader configuration object. @xref{Bootloader Configuration}.
13565 This is the label (a string) as it appears in the bootloader's menu entry.
13566 The default label includes the kernel name and version.
13568 @item @code{keyboard-layout} (default: @code{#f})
13569 This field specifies the keyboard layout to use in the console. It can be
13570 either @code{#f}, in which case the default keyboard layout is used (usually
13571 US English), or a @code{<keyboard-layout>} record. @xref{Keyboard Layout},
13572 for more information.
13574 This keyboard layout is in effect as soon as the kernel has booted. For
13575 instance, it is the keyboard layout in effect when you type a passphrase if
13576 your root file system is on a @code{luks-device-mapping} mapped device
13577 (@pxref{Mapped Devices}).
13580 This does @emph{not} specify the keyboard layout used by the bootloader, nor
13581 that used by the graphical display server. @xref{Bootloader Configuration},
13582 for information on how to specify the bootloader's keyboard layout. @xref{X
13583 Window}, for information on how to specify the keyboard layout used by the X
13587 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
13589 @cindex initial RAM disk
13590 The list of Linux kernel modules that need to be available in the
13591 initial RAM disk. @xref{Initial RAM Disk}.
13593 @item @code{initrd} (default: @code{base-initrd})
13594 A procedure that returns an initial RAM disk for the Linux
13595 kernel. This field is provided to support low-level customization and
13596 should rarely be needed for casual use. @xref{Initial RAM Disk}.
13598 @item @code{firmware} (default: @code{%base-firmware})
13600 List of firmware packages loadable by the operating system kernel.
13602 The default includes firmware needed for Atheros- and Broadcom-based
13603 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
13604 respectively). @xref{Hardware Considerations}, for more info on
13605 supported hardware.
13607 @item @code{host-name}
13610 @item @code{hosts-file}
13612 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
13613 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
13614 Reference Manual}). The default is a file with entries for
13615 @code{localhost} and @var{host-name}.
13617 @item @code{mapped-devices} (default: @code{'()})
13618 A list of mapped devices. @xref{Mapped Devices}.
13620 @item @code{file-systems}
13621 A list of file systems. @xref{File Systems}.
13623 @cindex swap devices
13625 @item @code{swap-devices} (default: @code{'()})
13626 A list of UUIDs, file system labels, or strings identifying devices or
13627 files to be used for ``swap
13628 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
13629 Manual}). Here are some examples:
13632 @item (list (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb"))
13633 Use the swap partition with the given UUID@. You can learn the UUID of a
13634 Linux swap partition by running @command{swaplabel @var{device}}, where
13635 @var{device} is the @file{/dev} file name of that partition.
13637 @item (list (file-system-label "swap"))
13638 Use the partition with label @code{swap}. Again, the
13639 @command{swaplabel} command allows you to view and change the label of a
13640 Linux swap partition.
13642 @item (list "/swapfile")
13643 Use the file @file{/swapfile} as swap space.
13645 @item (list "/dev/sda3" "/dev/sdb2")
13646 Use the @file{/dev/sda3} and @file{/dev/sdb2} partitions as swap space.
13647 We recommend referring to swap devices by UUIDs or labels as shown above
13651 It is possible to specify a swap file in a file system on a mapped
13652 device (under @file{/dev/mapper}), provided that the necessary device
13653 mapping and file system are also specified. @xref{Mapped Devices} and
13654 @ref{File Systems}.
13656 @item @code{users} (default: @code{%base-user-accounts})
13657 @itemx @code{groups} (default: @code{%base-groups})
13658 List of user accounts and groups. @xref{User Accounts}.
13660 If the @code{users} list lacks a user account with UID@tie{}0, a
13661 ``root'' account with UID@tie{}0 is automatically added.
13663 @item @code{skeletons} (default: @code{(default-skeletons)})
13664 A list of target file name/file-like object tuples (@pxref{G-Expressions,
13665 file-like objects}). These are the skeleton files that will be added to
13666 the home directory of newly-created user accounts.
13668 For instance, a valid value may look like this:
13671 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
13672 (".guile" ,(plain-file "guile"
13673 "(use-modules (ice-9 readline))
13674 (activate-readline)")))
13677 @item @code{issue} (default: @code{%default-issue})
13678 A string denoting the contents of the @file{/etc/issue} file, which is
13679 displayed when users log in on a text console.
13681 @item @code{packages} (default: @code{%base-packages})
13682 A list of packages to be installed in the global profile, which is accessible
13683 at @file{/run/current-system/profile}. Each element is either a package
13684 variable or a package/output tuple. Here's a simple example of both:
13687 (cons* git ; the default "out" output
13688 (list git "send-email") ; another output of git
13689 %base-packages) ; the default set
13692 The default set includes core utilities and it is good practice to
13693 install non-core utilities in user profiles (@pxref{Invoking guix
13696 @item @code{timezone}
13697 A timezone identifying string---e.g., @code{"Europe/Paris"}.
13699 You can run the @command{tzselect} command to find out which timezone
13700 string corresponds to your region. Choosing an invalid timezone name
13701 causes @command{guix system} to fail.
13703 @item @code{locale} (default: @code{"en_US.utf8"})
13704 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
13705 Library Reference Manual}). @xref{Locales}, for more information.
13707 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
13708 The list of locale definitions to be compiled and that may be used at
13709 run time. @xref{Locales}.
13711 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
13712 The list of GNU@tie{}libc packages whose locale data and tools are used
13713 to build the locale definitions. @xref{Locales}, for compatibility
13714 considerations that justify this option.
13716 @item @code{name-service-switch} (default: @code{%default-nss})
13717 Configuration of the libc name service switch (NSS)---a
13718 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
13721 @item @code{services} (default: @code{%base-services})
13722 A list of service objects denoting system services. @xref{Services}.
13724 @cindex essential services
13725 @item @code{essential-services} (default: ...)
13726 The list of ``essential services''---i.e., things like instances of
13727 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
13728 Reference}), which are derived from the operating system definition itself.
13729 As a user you should @emph{never} need to touch this field.
13731 @item @code{pam-services} (default: @code{(base-pam-services)})
13733 @cindex pluggable authentication modules
13734 Linux @dfn{pluggable authentication module} (PAM) services.
13735 @c FIXME: Add xref to PAM services section.
13737 @item @code{setuid-programs} (default: @code{%setuid-programs})
13738 List of string-valued G-expressions denoting setuid programs.
13739 @xref{Setuid Programs}.
13741 @item @code{sudoers-file} (default: @code{%sudoers-specification})
13742 @cindex sudoers file
13743 The contents of the @file{/etc/sudoers} file as a file-like object
13744 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
13746 This file specifies which users can use the @command{sudo} command, what
13747 they are allowed to do, and what privileges they may gain. The default
13748 is that only @code{root} and members of the @code{wheel} group may use
13753 @deffn {Scheme Syntax} this-operating-system
13754 When used in the @emph{lexical scope} of an operating system field definition,
13755 this identifier resolves to the operating system being defined.
13757 The example below shows how to refer to the operating system being defined in
13758 the definition of the @code{label} field:
13761 (use-modules (gnu) (guix))
13765 (label (package-full-name
13766 (operating-system-kernel this-operating-system))))
13769 It is an error to refer to @code{this-operating-system} outside an operating
13776 @section File Systems
13778 The list of file systems to be mounted is specified in the
13779 @code{file-systems} field of the operating system declaration
13780 (@pxref{Using the Configuration System}). Each file system is declared
13781 using the @code{file-system} form, like this:
13785 (mount-point "/home")
13786 (device "/dev/sda3")
13790 As usual, some of the fields are mandatory---those shown in the example
13791 above---while others can be omitted. These are described below.
13793 @deftp {Data Type} file-system
13794 Objects of this type represent file systems to be mounted. They
13795 contain the following members:
13799 This is a string specifying the type of the file system---e.g.,
13802 @item @code{mount-point}
13803 This designates the place where the file system is to be mounted.
13805 @item @code{device}
13806 This names the ``source'' of the file system. It can be one of three
13807 things: a file system label, a file system UUID, or the name of a
13808 @file{/dev} node. Labels and UUIDs offer a way to refer to file
13809 systems without having to hard-code their actual device
13810 name@footnote{Note that, while it is tempting to use
13811 @file{/dev/disk/by-uuid} and similar device names to achieve the same
13812 result, this is not recommended: These special device nodes are created
13813 by the udev daemon and may be unavailable at the time the device is
13816 @findex file-system-label
13817 File system labels are created using the @code{file-system-label}
13818 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
13819 plain strings. Here's an example of a file system referred to by its
13820 label, as shown by the @command{e2label} command:
13824 (mount-point "/home")
13826 (device (file-system-label "my-home")))
13830 UUIDs are converted from their string representation (as shown by the
13831 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
13832 @code{uuid} form expects 16-byte UUIDs as defined in
13833 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
13834 form of UUID used by the ext2 family of file systems and others, but it
13835 is different from ``UUIDs'' found in FAT file systems, for instance.},
13840 (mount-point "/home")
13842 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
13845 When the source of a file system is a mapped device (@pxref{Mapped
13846 Devices}), its @code{device} field @emph{must} refer to the mapped
13847 device name---e.g., @file{"/dev/mapper/root-partition"}.
13848 This is required so that
13849 the system knows that mounting the file system depends on having the
13850 corresponding device mapping established.
13852 @item @code{flags} (default: @code{'()})
13853 This is a list of symbols denoting mount flags. Recognized flags
13854 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
13855 access to special files), @code{no-suid} (ignore setuid and setgid
13856 bits), @code{no-atime} (do not update file access times),
13857 @code{strict-atime} (update file access time), @code{lazy-time} (only
13858 update time on the in-memory version of the file inode), and
13859 @code{no-exec} (disallow program execution).
13860 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
13861 Manual}, for more information on these flags.
13863 @item @code{options} (default: @code{#f})
13864 This is either @code{#f}, or a string denoting mount options passed to
13865 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
13866 Library Reference Manual}, for details and run @command{man 8 mount} for
13867 options for various file systems. Note that the
13868 @code{file-system-options->alist} and @code{alist->file-system-options}
13869 procedures from @code{(gnu system file-systems)} can be used to convert
13870 file system options given as an association list to the string
13871 representation, and vice-versa.
13873 @item @code{mount?} (default: @code{#t})
13874 This value indicates whether to automatically mount the file system when
13875 the system is brought up. When set to @code{#f}, the file system gets
13876 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
13877 is not automatically mounted.
13879 @item @code{needed-for-boot?} (default: @code{#f})
13880 This Boolean value indicates whether the file system is needed when
13881 booting. If that is true, then the file system is mounted when the
13882 initial RAM disk (initrd) is loaded. This is always the case, for
13883 instance, for the root file system.
13885 @item @code{check?} (default: @code{#t})
13886 This Boolean indicates whether the file system needs to be checked for
13887 errors before being mounted.
13889 @item @code{create-mount-point?} (default: @code{#f})
13890 When true, the mount point is created if it does not exist yet.
13892 @item @code{mount-may-fail?} (default: @code{#f})
13893 When true, this indicates that mounting this file system can fail but
13894 that should not be considered an error. This is useful in unusual
13895 cases; an example of this is @code{efivarfs}, a file system that can
13896 only be mounted on EFI/UEFI systems.
13898 @item @code{dependencies} (default: @code{'()})
13899 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
13900 representing file systems that must be mounted or mapped devices that
13901 must be opened before (and unmounted or closed after) this one.
13903 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
13904 a dependency of @file{/sys/fs/cgroup/cpu} and
13905 @file{/sys/fs/cgroup/memory}.
13907 Another example is a file system that depends on a mapped device, for
13908 example for an encrypted partition (@pxref{Mapped Devices}).
13912 @deffn {Scheme Procedure} file-system-label @var{str}
13913 This procedure returns an opaque file system label from @var{str}, a
13917 (file-system-label "home")
13918 @result{} #<file-system-label "home">
13921 File system labels are used to refer to file systems by label rather
13922 than by device name. See above for examples.
13925 The @code{(gnu system file-systems)} exports the following useful
13928 @defvr {Scheme Variable} %base-file-systems
13929 These are essential file systems that are required on normal systems,
13930 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
13931 below). Operating system declarations should always contain at least
13935 @defvr {Scheme Variable} %pseudo-terminal-file-system
13936 This is the file system to be mounted as @file{/dev/pts}. It supports
13937 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
13938 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
13939 Manual}). Pseudo-terminals are used by terminal emulators such as
13943 @defvr {Scheme Variable} %shared-memory-file-system
13944 This file system is mounted as @file{/dev/shm} and is used to support
13945 memory sharing across processes (@pxref{Memory-mapped I/O,
13946 @code{shm_open},, libc, The GNU C Library Reference Manual}).
13949 @defvr {Scheme Variable} %immutable-store
13950 This file system performs a read-only ``bind mount'' of
13951 @file{/gnu/store}, making it read-only for all the users including
13952 @code{root}. This prevents against accidental modification by software
13953 running as @code{root} or by system administrators.
13955 The daemon itself is still able to write to the store: it remounts it
13956 read-write in its own ``name space.''
13959 @defvr {Scheme Variable} %binary-format-file-system
13960 The @code{binfmt_misc} file system, which allows handling of arbitrary
13961 executable file types to be delegated to user space. This requires the
13962 @code{binfmt.ko} kernel module to be loaded.
13965 @defvr {Scheme Variable} %fuse-control-file-system
13966 The @code{fusectl} file system, which allows unprivileged users to mount
13967 and unmount user-space FUSE file systems. This requires the
13968 @code{fuse.ko} kernel module to be loaded.
13971 The @code{(gnu system uuid)} module provides tools to deal with file
13972 system ``unique identifiers'' (UUIDs).
13974 @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
13975 Return an opaque UUID (unique identifier) object of the given @var{type}
13976 (a symbol) by parsing @var{str} (a string):
13979 (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
13980 @result{} #<<uuid> type: dce bv: @dots{}>
13982 (uuid "1234-ABCD" 'fat)
13983 @result{} #<<uuid> type: fat bv: @dots{}>
13986 @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
13987 @code{ntfs}, or one of the commonly found synonyms for these.
13989 UUIDs are another way to unambiguously refer to file systems in
13990 operating system configuration. See the examples above.
13994 @node Btrfs file system
13995 @subsection Btrfs file system
13997 The Btrfs has special features, such as subvolumes, that merit being
13998 explained in more details. The following section attempts to cover
13999 basic as well as complex uses of a Btrfs file system with the Guix
14002 In its simplest usage, a Btrfs file system can be described, for
14007 (mount-point "/home")
14009 (device (file-system-label "my-home")))
14012 The example below is more complex, as it makes use of a Btrfs
14013 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
14014 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
14015 dependency on @code{mapped-devices}):
14019 (device (file-system-label "my-btrfs-pool"))
14022 (options "subvol=rootfs")
14023 (dependencies mapped-devices))
14026 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
14027 top level during the early boot, and rely on their configuration to
14028 refer to the correct subvolume path within that top level. The
14029 bootloaders operating in this way typically produce their configuration
14030 on a running system where the Btrfs partitions are already mounted and
14031 where the subvolume information is readily available. As an example,
14032 @command{grub-mkconfig}, the configuration generator command shipped
14033 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
14034 path of a subvolume.
14036 The Guix System produces a bootloader configuration using the operating
14037 system configuration as its sole input; it is therefore necessary to
14038 extract the subvolume name on which @file{/gnu/store} lives (if any)
14039 from that operating system configuration. To better illustrate,
14040 consider a subvolume named 'rootfs' which contains the root file system
14041 data. In such situation, the GRUB bootloader would only see the top
14042 level of the root Btrfs partition, e.g.:
14046 ├── rootfs (subvolume directory)
14047 ├── gnu (normal directory)
14048 ├── store (normal directory)
14052 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
14053 of the kernel, initrd binaries and any other files referred to in the
14054 GRUB configuration that must be found during the early boot.
14056 The next example shows a nested hierarchy of subvolumes and
14061 ├── rootfs (subvolume)
14062 ├── gnu (normal directory)
14063 ├── store (subvolume)
14067 This scenario would work without mounting the 'store' subvolume.
14068 Mounting 'rootfs' is sufficient, since the subvolume name matches its
14069 intended mount point in the file system hierarchy. Alternatively, the
14070 'store' subvolume could be referred to by setting the @code{subvol}
14071 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
14073 Finally, a more contrived example of nested subvolumes:
14077 ├── root-snapshots (subvolume)
14078 ├── root-current (subvolume)
14079 ├── guix-store (subvolume)
14083 Here, the 'guix-store' subvolume doesn't match its intended mount point,
14084 so it is necessary to mount it. The subvolume must be fully specified,
14085 by passing its file name to the @code{subvol} option. To illustrate,
14086 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
14087 a file system declaration such as:
14091 (device (file-system-label "btrfs-pool-1"))
14092 (mount-point "/gnu/store")
14094 (options "subvol=root-snapshots/root-current/guix-store,\
14095 compress-force=zstd,space_cache=v2"))
14098 @node Mapped Devices
14099 @section Mapped Devices
14101 @cindex device mapping
14102 @cindex mapped devices
14103 The Linux kernel has a notion of @dfn{device mapping}: a block device,
14104 such as a hard disk partition, can be @dfn{mapped} into another device,
14105 usually in @code{/dev/mapper/},
14106 with additional processing over the data that flows through
14107 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
14108 concept of a ``mapped device'' and that of a file system: both boil down
14109 to @emph{translating} input/output operations made on a file to
14110 operations on its backing store. Thus, the Hurd implements mapped
14111 devices, like file systems, using the generic @dfn{translator} mechanism
14112 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
14113 typical example is encryption device mapping: all writes to the mapped
14114 device are encrypted, and all reads are deciphered, transparently.
14115 Guix extends this notion by considering any device or set of devices that
14116 are @dfn{transformed} in some way to create a new device; for instance,
14117 RAID devices are obtained by @dfn{assembling} several other devices, such
14118 as hard disks or partitions, into a new one that behaves as one partition.
14120 Mapped devices are declared using the @code{mapped-device} form,
14121 defined as follows; for examples, see below.
14123 @deftp {Data Type} mapped-device
14124 Objects of this type represent device mappings that will be made when
14125 the system boots up.
14129 This is either a string specifying the name of the block device to be mapped,
14130 such as @code{"/dev/sda3"}, or a list of such strings when several devices
14131 need to be assembled for creating a new one. In case of LVM this is a
14132 string specifying name of the volume group to be mapped.
14135 This string specifies the name of the resulting mapped device. For
14136 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
14137 specifying @code{"my-partition"} leads to the creation of
14138 the @code{"/dev/mapper/my-partition"} device.
14139 For RAID devices of type @code{raid-device-mapping}, the full device name
14140 such as @code{"/dev/md0"} needs to be given.
14141 LVM logical volumes of type @code{lvm-device-mapping} need to
14142 be specified as @code{"VGNAME-LVNAME"}.
14145 This list of strings specifies names of the resulting mapped devices in case
14146 there are several. The format is identical to @var{target}.
14149 This must be a @code{mapped-device-kind} object, which specifies how
14150 @var{source} is mapped to @var{target}.
14154 @defvr {Scheme Variable} luks-device-mapping
14155 This defines LUKS block device encryption using the @command{cryptsetup}
14156 command from the package with the same name. It relies on the
14157 @code{dm-crypt} Linux kernel module.
14160 @defvr {Scheme Variable} raid-device-mapping
14161 This defines a RAID device, which is assembled using the @code{mdadm}
14162 command from the package with the same name. It requires a Linux kernel
14163 module for the appropriate RAID level to be loaded, such as @code{raid456}
14164 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
14167 @cindex LVM, logical volume manager
14168 @defvr {Scheme Variable} lvm-device-mapping
14169 This defines one or more logical volumes for the Linux
14170 @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
14171 The volume group is activated by the @command{vgchange} command from the
14172 @code{lvm2} package.
14175 @cindex disk encryption
14177 The following example specifies a mapping from @file{/dev/sda3} to
14178 @file{/dev/mapper/home} using LUKS---the
14179 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
14180 standard mechanism for disk encryption.
14181 The @file{/dev/mapper/home}
14182 device can then be used as the @code{device} of a @code{file-system}
14183 declaration (@pxref{File Systems}).
14187 (source "/dev/sda3")
14189 (type luks-device-mapping))
14192 Alternatively, to become independent of device numbering, one may obtain
14193 the LUKS UUID (@dfn{unique identifier}) of the source device by a
14197 cryptsetup luksUUID /dev/sda3
14200 and use it as follows:
14204 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
14206 (type luks-device-mapping))
14209 @cindex swap encryption
14210 It is also desirable to encrypt swap space, since swap space may contain
14211 sensitive data. One way to accomplish that is to use a swap file in a
14212 file system on a device mapped via LUKS encryption. In this way, the
14213 swap file is encrypted because the entire device is encrypted.
14214 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
14216 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
14217 may be declared as follows:
14221 (source (list "/dev/sda1" "/dev/sdb1"))
14222 (target "/dev/md0")
14223 (type raid-device-mapping))
14226 The @file{/dev/md0} device can then be used as the @code{device} of a
14227 @code{file-system} declaration (@pxref{File Systems}).
14228 Note that the RAID level need not be given; it is chosen during the
14229 initial creation and formatting of the RAID device and is determined
14230 automatically later.
14232 LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
14233 be declared as follows:
14238 (targets (list "vg0-alpha" "vg0-beta"))
14239 (type lvm-device-mapping))
14242 Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
14243 then be used as the @code{device} of a @code{file-system} declaration
14244 (@pxref{File Systems}).
14246 @node User Accounts
14247 @section User Accounts
14251 @cindex user accounts
14252 User accounts and groups are entirely managed through the
14253 @code{operating-system} declaration. They are specified with the
14254 @code{user-account} and @code{user-group} forms:
14260 (supplementary-groups '("wheel" ;allow use of sudo, etc.
14261 "audio" ;sound card
14262 "video" ;video devices such as webcams
14263 "cdrom")) ;the good ol' CD-ROM
14264 (comment "Bob's sister"))
14267 Here's a user account that uses a different shell and a custom home
14268 directory (the default would be @file{"/home/bob"}):
14274 (comment "Alice's bro")
14275 (shell (file-append zsh "/bin/zsh"))
14276 (home-directory "/home/robert"))
14279 When booting or upon completion of @command{guix system reconfigure},
14280 the system ensures that only the user accounts and groups specified in
14281 the @code{operating-system} declaration exist, and with the specified
14282 properties. Thus, account or group creations or modifications made by
14283 directly invoking commands such as @command{useradd} are lost upon
14284 reconfiguration or reboot. This ensures that the system remains exactly
14287 @deftp {Data Type} user-account
14288 Objects of this type represent user accounts. The following members may
14293 The name of the user account.
14297 This is the name (a string) or identifier (a number) of the user group
14298 this account belongs to.
14300 @item @code{supplementary-groups} (default: @code{'()})
14301 Optionally, this can be defined as a list of group names that this
14302 account belongs to.
14304 @item @code{uid} (default: @code{#f})
14305 This is the user ID for this account (a number), or @code{#f}. In the
14306 latter case, a number is automatically chosen by the system when the
14307 account is created.
14309 @item @code{comment} (default: @code{""})
14310 A comment about the account, such as the account owner's full name.
14312 @item @code{home-directory}
14313 This is the name of the home directory for the account.
14315 @item @code{create-home-directory?} (default: @code{#t})
14316 Indicates whether the home directory of this account should be created
14317 if it does not exist yet.
14319 @item @code{shell} (default: Bash)
14320 This is a G-expression denoting the file name of a program to be used as
14321 the shell (@pxref{G-Expressions}). For example, you would refer to the
14322 Bash executable like this:
14325 (file-append bash "/bin/bash")
14329 ... and to the Zsh executable like that:
14332 (file-append zsh "/bin/zsh")
14335 @item @code{system?} (default: @code{#f})
14336 This Boolean value indicates whether the account is a ``system''
14337 account. System accounts are sometimes treated specially; for instance,
14338 graphical login managers do not list them.
14340 @anchor{user-account-password}
14341 @cindex password, for user accounts
14342 @item @code{password} (default: @code{#f})
14343 You would normally leave this field to @code{#f}, initialize user
14344 passwords as @code{root} with the @command{passwd} command, and then let
14345 users change it with @command{passwd}. Passwords set with
14346 @command{passwd} are of course preserved across reboot and
14349 If you @emph{do} want to set an initial password for an account, then
14350 this field must contain the encrypted password, as a string. You can use the
14351 @code{crypt} procedure for this purpose:
14358 ;; Specify a SHA-512-hashed initial password.
14359 (password (crypt "InitialPassword!" "$6$abc")))
14363 The hash of this initial password will be available in a file in
14364 @file{/gnu/store}, readable by all the users, so this method must be used with
14368 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
14369 more information on password encryption, and @ref{Encryption,,, guile, GNU
14370 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
14376 User group declarations are even simpler:
14379 (user-group (name "students"))
14382 @deftp {Data Type} user-group
14383 This type is for, well, user groups. There are just a few fields:
14387 The name of the group.
14389 @item @code{id} (default: @code{#f})
14390 The group identifier (a number). If @code{#f}, a new number is
14391 automatically allocated when the group is created.
14393 @item @code{system?} (default: @code{#f})
14394 This Boolean value indicates whether the group is a ``system'' group.
14395 System groups have low numerical IDs.
14397 @item @code{password} (default: @code{#f})
14398 What, user groups can have a password? Well, apparently yes. Unless
14399 @code{#f}, this field specifies the password of the group.
14404 For convenience, a variable lists all the basic user groups one may
14407 @defvr {Scheme Variable} %base-groups
14408 This is the list of basic user groups that users and/or packages expect
14409 to be present on the system. This includes groups such as ``root'',
14410 ``wheel'', and ``users'', as well as groups used to control access to
14411 specific devices such as ``audio'', ``disk'', and ``cdrom''.
14414 @defvr {Scheme Variable} %base-user-accounts
14415 This is the list of basic system accounts that programs may expect to
14416 find on a GNU/Linux system, such as the ``nobody'' account.
14418 Note that the ``root'' account is not included here. It is a
14419 special-case and is automatically added whether or not it is specified.
14422 @node Keyboard Layout
14423 @section Keyboard Layout
14425 @cindex keyboard layout
14427 To specify what each key of your keyboard does, you need to tell the operating
14428 system what @dfn{keyboard layout} you want to use. The default, when nothing
14429 is specified, is the US English QWERTY layout for 105-key PC keyboards.
14430 However, German speakers will usually prefer the German QWERTZ layout, French
14431 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
14432 or bépo, and they might even want to further customize the effect of some of
14433 the keys. This section explains how to get that done.
14435 @cindex keyboard layout, definition
14436 There are three components that will want to know about your keyboard layout:
14440 The @emph{bootloader} may want to know what keyboard layout you want to use
14441 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
14442 you want, for instance, to make sure that you can type the passphrase of your
14443 encrypted root partition using the right layout.
14446 The @emph{operating system kernel}, Linux, will need that so that the console
14447 is properly configured (@pxref{operating-system Reference,
14448 @code{keyboard-layout}}).
14451 The @emph{graphical display server}, usually Xorg, also has its own idea of
14452 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
14455 Guix allows you to configure all three separately but, fortunately, it allows
14456 you to share the same keyboard layout for all three components.
14458 @cindex XKB, keyboard layouts
14459 Keyboard layouts are represented by records created by the
14460 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
14461 the X Keyboard extension (XKB), each layout has four attributes: a name (often
14462 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
14463 optional variant name, an optional keyboard model name, and a possibly empty
14464 list of additional options. In most cases the layout name is all you care
14467 @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
14468 [#:model] [#:options '()]
14469 Return a new keyboard layout with the given @var{name} and @var{variant}.
14471 @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
14472 string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
14473 @code{xkeyboard-config} package for valid options.
14476 Here are a few examples:
14479 ;; The German QWERTZ layout. Here we assume a standard
14480 ;; "pc105" keyboard model.
14481 (keyboard-layout "de")
14483 ;; The bépo variant of the French layout.
14484 (keyboard-layout "fr" "bepo")
14486 ;; The Catalan layout.
14487 (keyboard-layout "es" "cat")
14489 ;; Arabic layout with "Alt-Shift" to switch to US layout.
14490 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
14492 ;; The Latin American Spanish layout. In addition, the
14493 ;; "Caps Lock" key is used as an additional "Ctrl" key,
14494 ;; and the "Menu" key is used as a "Compose" key to enter
14495 ;; accented letters.
14496 (keyboard-layout "latam"
14497 #:options '("ctrl:nocaps" "compose:menu"))
14499 ;; The Russian layout for a ThinkPad keyboard.
14500 (keyboard-layout "ru" #:model "thinkpad")
14502 ;; The "US international" layout, which is the US layout plus
14503 ;; dead keys to enter accented characters. This is for an
14504 ;; Apple MacBook keyboard.
14505 (keyboard-layout "us" "intl" #:model "macbook78")
14508 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
14509 for a complete list of supported layouts, variants, and models.
14511 @cindex keyboard layout, configuration
14512 Let's say you want your system to use the Turkish keyboard layout throughout
14513 your system---bootloader, console, and Xorg. Here's what your system
14514 configuration would look like:
14516 @findex set-xorg-configuration
14518 ;; Using the Turkish layout for the bootloader, the console,
14523 (keyboard-layout (keyboard-layout "tr")) ;for the console
14524 (bootloader (bootloader-configuration
14525 (bootloader grub-efi-bootloader)
14526 (target "/boot/efi")
14527 (keyboard-layout keyboard-layout))) ;for GRUB
14528 (services (cons (set-xorg-configuration
14529 (xorg-configuration ;for Xorg
14530 (keyboard-layout keyboard-layout)))
14531 %desktop-services)))
14534 In the example above, for GRUB and for Xorg, we just refer to the
14535 @code{keyboard-layout} field defined above, but we could just as well refer to
14536 a different layout. The @code{set-xorg-configuration} procedure communicates
14537 the desired Xorg configuration to the graphical log-in manager, by default
14540 We've discussed how to specify the @emph{default} keyboard layout of your
14541 system when it starts, but you can also adjust it at run time:
14545 If you're using GNOME, its settings panel has a ``Region & Language'' entry
14546 where you can select one or more keyboard layouts.
14549 Under Xorg, the @command{setxkbmap} command (from the same-named package)
14550 allows you to change the current layout. For example, this is how you would
14551 change the layout to US Dvorak:
14554 setxkbmap us dvorak
14558 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
14559 console. However, note that @code{loadkeys} does @emph{not} use the XKB
14560 keyboard layout categorization described above. The command below loads the
14561 French bépo layout:
14572 A @dfn{locale} defines cultural conventions for a particular language
14573 and region of the world (@pxref{Locales,,, libc, The GNU C Library
14574 Reference Manual}). Each locale has a name that typically has the form
14575 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
14576 @code{fr_LU.utf8} designates the locale for the French language, with
14577 cultural conventions from Luxembourg, and using the UTF-8 encoding.
14579 @cindex locale definition
14580 Usually, you will want to specify the default locale for the machine
14581 using the @code{locale} field of the @code{operating-system} declaration
14582 (@pxref{operating-system Reference, @code{locale}}).
14584 The selected locale is automatically added to the @dfn{locale
14585 definitions} known to the system if needed, with its codeset inferred
14586 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
14587 @code{UTF-8} codeset. Additional locale definitions can be specified in
14588 the @code{locale-definitions} slot of @code{operating-system}---this is
14589 useful, for instance, if the codeset could not be inferred from the
14590 locale name. The default set of locale definitions includes some widely
14591 used locales, but not all the available locales, in order to save space.
14593 For instance, to add the North Frisian locale for Germany, the value of
14597 (cons (locale-definition
14598 (name "fy_DE.utf8") (source "fy_DE"))
14599 %default-locale-definitions)
14602 Likewise, to save space, one might want @code{locale-definitions} to
14603 list only the locales that are actually used, as in:
14606 (list (locale-definition
14607 (name "ja_JP.eucjp") (source "ja_JP")
14608 (charset "EUC-JP")))
14612 The compiled locale definitions are available at
14613 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
14614 version, which is the default location where the GNU@tie{}libc provided
14615 by Guix looks for locale data. This can be overridden using the
14616 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
14617 @env{LOCPATH} and locale packages}).
14619 The @code{locale-definition} form is provided by the @code{(gnu system
14620 locale)} module. Details are given below.
14622 @deftp {Data Type} locale-definition
14623 This is the data type of a locale definition.
14628 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
14629 Reference Manual}, for more information on locale names.
14631 @item @code{source}
14632 The name of the source for that locale. This is typically the
14633 @code{@var{language}_@var{territory}} part of the locale name.
14635 @item @code{charset} (default: @code{"UTF-8"})
14636 The ``character set'' or ``code set'' for that locale,
14637 @uref{https://www.iana.org/assignments/character-sets, as defined by
14643 @defvr {Scheme Variable} %default-locale-definitions
14644 A list of commonly used UTF-8 locales, used as the default
14645 value of the @code{locale-definitions} field of @code{operating-system}
14648 @cindex locale name
14649 @cindex normalized codeset in locale names
14650 These locale definitions use the @dfn{normalized codeset} for the part
14651 that follows the dot in the name (@pxref{Using gettextized software,
14652 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
14653 instance it has @code{uk_UA.utf8} but @emph{not}, say,
14654 @code{uk_UA.UTF-8}.
14657 @subsection Locale Data Compatibility Considerations
14659 @cindex incompatibility, of locale data
14660 @code{operating-system} declarations provide a @code{locale-libcs} field
14661 to specify the GNU@tie{}libc packages that are used to compile locale
14662 declarations (@pxref{operating-system Reference}). ``Why would I
14663 care?'', you may ask. Well, it turns out that the binary format of
14664 locale data is occasionally incompatible from one libc version to
14667 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
14668 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
14669 For instance, a program linked against libc version 2.21 is unable to
14670 read locale data produced with libc 2.22; worse, that program
14671 @emph{aborts} instead of simply ignoring the incompatible locale
14672 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
14673 the incompatible locale data, which is already an improvement.}.
14674 Similarly, a program linked against libc 2.22 can read most, but not
14675 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
14676 data is incompatible); thus calls to @code{setlocale} may fail, but
14677 programs will not abort.
14679 The ``problem'' with Guix is that users have a lot of freedom: They can
14680 choose whether and when to upgrade software in their profiles, and might
14681 be using a libc version different from the one the system administrator
14682 used to build the system-wide locale data.
14684 Fortunately, unprivileged users can also install their own locale data
14685 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
14686 @env{GUIX_LOCPATH} and locale packages}).
14688 Still, it is best if the system-wide locale data at
14689 @file{/run/current-system/locale} is built for all the libc versions
14690 actually in use on the system, so that all the programs can access
14691 it---this is especially crucial on a multi-user system. To do that, the
14692 administrator can specify several libc packages in the
14693 @code{locale-libcs} field of @code{operating-system}:
14696 (use-package-modules base)
14700 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
14703 This example would lead to a system containing locale definitions for
14704 both libc 2.21 and the current version of libc in
14705 @file{/run/current-system/locale}.
14711 @cindex system services
14712 An important part of preparing an @code{operating-system} declaration is
14713 listing @dfn{system services} and their configuration (@pxref{Using the
14714 Configuration System}). System services are typically daemons launched
14715 when the system boots, or other actions needed at that time---e.g.,
14716 configuring network access.
14718 Guix has a broad definition of ``service'' (@pxref{Service
14719 Composition}), but many services are managed by the GNU@tie{}Shepherd
14720 (@pxref{Shepherd Services}). On a running system, the @command{herd}
14721 command allows you to list the available services, show their status,
14722 start and stop them, or do other specific operations (@pxref{Jump
14723 Start,,, shepherd, The GNU Shepherd Manual}). For example:
14729 The above command, run as @code{root}, lists the currently defined
14730 services. The @command{herd doc} command shows a synopsis of the given
14731 service and its associated actions:
14735 Run libc's name service cache daemon (nscd).
14737 # herd doc nscd action invalidate
14738 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
14741 The @command{start}, @command{stop}, and @command{restart} sub-commands
14742 have the effect you would expect. For instance, the commands below stop
14743 the nscd service and restart the Xorg display server:
14747 Service nscd has been stopped.
14748 # herd restart xorg-server
14749 Service xorg-server has been stopped.
14750 Service xorg-server has been started.
14753 The following sections document the available services, starting with
14754 the core services, that may be used in an @code{operating-system}
14758 * Base Services:: Essential system services.
14759 * Scheduled Job Execution:: The mcron service.
14760 * Log Rotation:: The rottlog service.
14761 * Networking Services:: Network setup, SSH daemon, etc.
14762 * Unattended Upgrades:: Automated system upgrades.
14763 * X Window:: Graphical display.
14764 * Printing Services:: Local and remote printer support.
14765 * Desktop Services:: D-Bus and desktop services.
14766 * Sound Services:: ALSA and Pulseaudio services.
14767 * Database Services:: SQL databases, key-value stores, etc.
14768 * Mail Services:: IMAP, POP3, SMTP, and all that.
14769 * Messaging Services:: Messaging services.
14770 * Telephony Services:: Telephony services.
14771 * File-Sharing Services:: File-sharing services.
14772 * Monitoring Services:: Monitoring services.
14773 * Kerberos Services:: Kerberos services.
14774 * LDAP Services:: LDAP services.
14775 * Web Services:: Web servers.
14776 * Certificate Services:: TLS certificates via Let's Encrypt.
14777 * DNS Services:: DNS daemons.
14778 * VPN Services:: VPN daemons.
14779 * Network File System:: NFS related services.
14780 * Continuous Integration:: The Cuirass service.
14781 * Power Management Services:: Extending battery life.
14782 * Audio Services:: The MPD.
14783 * Virtualization Services:: Virtualization services.
14784 * Version Control Services:: Providing remote access to Git repositories.
14785 * Game Services:: Game servers.
14786 * PAM Mount Service:: Service to mount volumes when logging in.
14787 * Guix Services:: Services relating specifically to Guix.
14788 * Linux Services:: Services tied to the Linux kernel.
14789 * Hurd Services:: Services specific for a Hurd System.
14790 * Miscellaneous Services:: Other services.
14793 @node Base Services
14794 @subsection Base Services
14796 The @code{(gnu services base)} module provides definitions for the basic
14797 services that one expects from the system. The services exported by
14798 this module are listed below.
14800 @defvr {Scheme Variable} %base-services
14801 This variable contains a list of basic services (@pxref{Service Types
14802 and Services}, for more information on service objects) one would
14803 expect from the system: a login service (mingetty) on each tty, syslogd,
14804 the libc name service cache daemon (nscd), the udev device manager, and
14807 This is the default value of the @code{services} field of
14808 @code{operating-system} declarations. Usually, when customizing a
14809 system, you will want to append services to @code{%base-services}, like
14813 (append (list (service avahi-service-type)
14814 (service openssh-service-type))
14819 @defvr {Scheme Variable} special-files-service-type
14820 This is the service that sets up ``special files'' such as
14821 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
14823 The value associated with @code{special-files-service-type} services
14824 must be a list of tuples where the first element is the ``special file''
14825 and the second element is its target. By default it is:
14827 @cindex @file{/bin/sh}
14828 @cindex @file{sh}, in @file{/bin}
14830 `(("/bin/sh" ,(file-append bash "/bin/sh")))
14833 @cindex @file{/usr/bin/env}
14834 @cindex @file{env}, in @file{/usr/bin}
14835 If you want to add, say, @code{/usr/bin/env} to your system, you can
14839 `(("/bin/sh" ,(file-append bash "/bin/sh"))
14840 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
14843 Since this is part of @code{%base-services}, you can use
14844 @code{modify-services} to customize the set of special files
14845 (@pxref{Service Reference, @code{modify-services}}). But the simple way
14846 to add a special file is @i{via} the @code{extra-special-file} procedure
14850 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
14851 Use @var{target} as the ``special file'' @var{file}.
14853 For example, adding the following lines to the @code{services} field of
14854 your operating system declaration leads to a @file{/usr/bin/env}
14858 (extra-special-file "/usr/bin/env"
14859 (file-append coreutils "/bin/env"))
14863 @deffn {Scheme Procedure} host-name-service @var{name}
14864 Return a service that sets the host name to @var{name}.
14867 @defvr {Scheme Variable} console-font-service-type
14868 Install the given fonts on the specified ttys (fonts are per
14869 virtual console on the kernel Linux). The value of this service is a list of
14870 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
14871 package or any valid argument to @command{setfont}, as in this example:
14874 `(("tty1" . "LatGrkCyr-8x16")
14875 ("tty2" . ,(file-append
14877 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
14878 ("tty3" . ,(file-append
14880 "/share/consolefonts/ter-132n"))) ; for HDPI
14884 @deffn {Scheme Procedure} login-service @var{config}
14885 Return a service to run login according to @var{config}, a
14886 @code{<login-configuration>} object, which specifies the message of the day,
14887 among other things.
14890 @deftp {Data Type} login-configuration
14891 This is the data type representing the configuration of login.
14896 @cindex message of the day
14897 A file-like object containing the ``message of the day''.
14899 @item @code{allow-empty-passwords?} (default: @code{#t})
14900 Allow empty passwords by default so that first-time users can log in when
14901 the 'root' account has just been created.
14906 @deffn {Scheme Procedure} mingetty-service @var{config}
14907 Return a service to run mingetty according to @var{config}, a
14908 @code{<mingetty-configuration>} object, which specifies the tty to run, among
14912 @deftp {Data Type} mingetty-configuration
14913 This is the data type representing the configuration of Mingetty, which
14914 provides the default implementation of virtual console log-in.
14919 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
14921 @item @code{auto-login} (default: @code{#f})
14922 When true, this field must be a string denoting the user name under
14923 which the system automatically logs in. When it is @code{#f}, a
14924 user name and password must be entered to log in.
14926 @item @code{login-program} (default: @code{#f})
14927 This must be either @code{#f}, in which case the default log-in program
14928 is used (@command{login} from the Shadow tool suite), or a gexp denoting
14929 the name of the log-in program.
14931 @item @code{login-pause?} (default: @code{#f})
14932 When set to @code{#t} in conjunction with @var{auto-login}, the user
14933 will have to press a key before the log-in shell is launched.
14935 @item @code{clear-on-logout?} (default: @code{#t})
14936 When set to @code{#t}, the screen will be cleared after logout.
14938 @item @code{mingetty} (default: @var{mingetty})
14939 The Mingetty package to use.
14944 @deffn {Scheme Procedure} agetty-service @var{config}
14945 Return a service to run agetty according to @var{config}, an
14946 @code{<agetty-configuration>} object, which specifies the tty to run,
14947 among other things.
14950 @deftp {Data Type} agetty-configuration
14951 This is the data type representing the configuration of agetty, which
14952 implements virtual and serial console log-in. See the @code{agetty(8)}
14953 man page for more information.
14958 The name of the console this agetty runs on, as a string---e.g.,
14959 @code{"ttyS0"}. This argument is optional, it will default to
14960 a reasonable default serial port used by the kernel Linux.
14962 For this, if there is a value for an option @code{agetty.tty} in the kernel
14963 command line, agetty will extract the device name of the serial port
14964 from it and use that.
14966 If not and if there is a value for an option @code{console} with a tty in
14967 the Linux command line, agetty will extract the device name of the
14968 serial port from it and use that.
14970 In both cases, agetty will leave the other serial device settings
14971 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
14974 @item @code{baud-rate} (default: @code{#f})
14975 A string containing a comma-separated list of one or more baud rates, in
14978 @item @code{term} (default: @code{#f})
14979 A string containing the value used for the @env{TERM} environment
14982 @item @code{eight-bits?} (default: @code{#f})
14983 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
14986 @item @code{auto-login} (default: @code{#f})
14987 When passed a login name, as a string, the specified user will be logged
14988 in automatically without prompting for their login name or password.
14990 @item @code{no-reset?} (default: @code{#f})
14991 When @code{#t}, don't reset terminal cflags (control modes).
14993 @item @code{host} (default: @code{#f})
14994 This accepts a string containing the ``login_host'', which will be written
14995 into the @file{/var/run/utmpx} file.
14997 @item @code{remote?} (default: @code{#f})
14998 When set to @code{#t} in conjunction with @var{host}, this will add an
14999 @code{-r} fakehost option to the command line of the login program
15000 specified in @var{login-program}.
15002 @item @code{flow-control?} (default: @code{#f})
15003 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
15005 @item @code{no-issue?} (default: @code{#f})
15006 When set to @code{#t}, the contents of the @file{/etc/issue} file will
15007 not be displayed before presenting the login prompt.
15009 @item @code{init-string} (default: @code{#f})
15010 This accepts a string that will be sent to the tty or modem before
15011 sending anything else. It can be used to initialize a modem.
15013 @item @code{no-clear?} (default: @code{#f})
15014 When set to @code{#t}, agetty will not clear the screen before showing
15017 @item @code{login-program} (default: (file-append shadow "/bin/login"))
15018 This must be either a gexp denoting the name of a log-in program, or
15019 unset, in which case the default value is the @command{login} from the
15022 @item @code{local-line} (default: @code{#f})
15023 Control the CLOCAL line flag. This accepts one of three symbols as
15024 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
15025 the default value chosen by agetty is @code{'auto}.
15027 @item @code{extract-baud?} (default: @code{#f})
15028 When set to @code{#t}, instruct agetty to try to extract the baud rate
15029 from the status messages produced by certain types of modems.
15031 @item @code{skip-login?} (default: @code{#f})
15032 When set to @code{#t}, do not prompt the user for a login name. This
15033 can be used with @var{login-program} field to use non-standard login
15036 @item @code{no-newline?} (default: @code{#f})
15037 When set to @code{#t}, do not print a newline before printing the
15038 @file{/etc/issue} file.
15040 @c Is this dangerous only when used with login-program, or always?
15041 @item @code{login-options} (default: @code{#f})
15042 This option accepts a string containing options that are passed to the
15043 login program. When used with the @var{login-program}, be aware that a
15044 malicious user could try to enter a login name containing embedded
15045 options that could be parsed by the login program.
15047 @item @code{login-pause} (default: @code{#f})
15048 When set to @code{#t}, wait for any key before showing the login prompt.
15049 This can be used in conjunction with @var{auto-login} to save memory by
15050 lazily spawning shells.
15052 @item @code{chroot} (default: @code{#f})
15053 Change root to the specified directory. This option accepts a directory
15056 @item @code{hangup?} (default: @code{#f})
15057 Use the Linux system call @code{vhangup} to do a virtual hangup of the
15058 specified terminal.
15060 @item @code{keep-baud?} (default: @code{#f})
15061 When set to @code{#t}, try to keep the existing baud rate. The baud
15062 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
15065 @item @code{timeout} (default: @code{#f})
15066 When set to an integer value, terminate if no user name could be read
15067 within @var{timeout} seconds.
15069 @item @code{detect-case?} (default: @code{#f})
15070 When set to @code{#t}, turn on support for detecting an uppercase-only
15071 terminal. This setting will detect a login name containing only
15072 uppercase letters as indicating an uppercase-only terminal and turn on
15073 some upper-to-lower case conversions. Note that this will not support
15074 Unicode characters.
15076 @item @code{wait-cr?} (default: @code{#f})
15077 When set to @code{#t}, wait for the user or modem to send a
15078 carriage-return or linefeed character before displaying
15079 @file{/etc/issue} or login prompt. This is typically used with the
15080 @var{init-string} option.
15082 @item @code{no-hints?} (default: @code{#f})
15083 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
15086 @item @code{no-hostname?} (default: @code{#f})
15087 By default, the hostname is printed. When this option is set to
15088 @code{#t}, no hostname will be shown at all.
15090 @item @code{long-hostname?} (default: @code{#f})
15091 By default, the hostname is only printed until the first dot. When this
15092 option is set to @code{#t}, the fully qualified hostname by
15093 @code{gethostname} or @code{getaddrinfo} is shown.
15095 @item @code{erase-characters} (default: @code{#f})
15096 This option accepts a string of additional characters that should be
15097 interpreted as backspace when the user types their login name.
15099 @item @code{kill-characters} (default: @code{#f})
15100 This option accepts a string that should be interpreted to mean ``ignore
15101 all previous characters'' (also called a ``kill'' character) when the user
15102 types their login name.
15104 @item @code{chdir} (default: @code{#f})
15105 This option accepts, as a string, a directory path that will be changed
15108 @item @code{delay} (default: @code{#f})
15109 This options accepts, as an integer, the number of seconds to sleep
15110 before opening the tty and displaying the login prompt.
15112 @item @code{nice} (default: @code{#f})
15113 This option accepts, as an integer, the nice value with which to run the
15114 @command{login} program.
15116 @item @code{extra-options} (default: @code{'()})
15117 This option provides an ``escape hatch'' for the user to provide arbitrary
15118 command-line arguments to @command{agetty} as a list of strings.
15123 @deffn {Scheme Procedure} kmscon-service-type @var{config}
15124 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
15125 according to @var{config}, a @code{<kmscon-configuration>} object, which
15126 specifies the tty to run, among other things.
15129 @deftp {Data Type} kmscon-configuration
15130 This is the data type representing the configuration of Kmscon, which
15131 implements virtual console log-in.
15135 @item @code{virtual-terminal}
15136 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
15138 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
15139 A gexp denoting the name of the log-in program. The default log-in program is
15140 @command{login} from the Shadow tool suite.
15142 @item @code{login-arguments} (default: @code{'("-p")})
15143 A list of arguments to pass to @command{login}.
15145 @item @code{auto-login} (default: @code{#f})
15146 When passed a login name, as a string, the specified user will be logged
15147 in automatically without prompting for their login name or password.
15149 @item @code{hardware-acceleration?} (default: #f)
15150 Whether to use hardware acceleration.
15152 @item @code{kmscon} (default: @var{kmscon})
15153 The Kmscon package to use.
15158 @cindex name service cache daemon
15160 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
15161 [#:name-services '()]
15162 Return a service that runs the libc name service cache daemon (nscd) with the
15163 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
15164 Service Switch}, for an example.
15166 For convenience, the Shepherd service for nscd provides the following actions:
15170 @cindex cache invalidation, nscd
15171 @cindex nscd, cache invalidation
15172 This invalidate the given cache. For instance, running:
15175 herd invalidate nscd hosts
15179 invalidates the host name lookup cache of nscd.
15182 Running @command{herd statistics nscd} displays information about nscd usage
15188 @defvr {Scheme Variable} %nscd-default-configuration
15189 This is the default @code{<nscd-configuration>} value (see below) used
15190 by @code{nscd-service}. It uses the caches defined by
15191 @code{%nscd-default-caches}; see below.
15194 @deftp {Data Type} nscd-configuration
15195 This is the data type representing the name service cache daemon (nscd)
15200 @item @code{name-services} (default: @code{'()})
15201 List of packages denoting @dfn{name services} that must be visible to
15202 the nscd---e.g., @code{(list @var{nss-mdns})}.
15204 @item @code{glibc} (default: @var{glibc})
15205 Package object denoting the GNU C Library providing the @command{nscd}
15208 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
15209 Name of the nscd log file. This is where debugging output goes when
15210 @code{debug-level} is strictly positive.
15212 @item @code{debug-level} (default: @code{0})
15213 Integer denoting the debugging levels. Higher numbers mean that more
15214 debugging output is logged.
15216 @item @code{caches} (default: @code{%nscd-default-caches})
15217 List of @code{<nscd-cache>} objects denoting things to be cached; see
15223 @deftp {Data Type} nscd-cache
15224 Data type representing a cache database of nscd and its parameters.
15228 @item @code{database}
15229 This is a symbol representing the name of the database to be cached.
15230 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
15231 @code{services}, which designate the corresponding NSS database
15232 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
15234 @item @code{positive-time-to-live}
15235 @itemx @code{negative-time-to-live} (default: @code{20})
15236 A number representing the number of seconds during which a positive or
15237 negative lookup result remains in cache.
15239 @item @code{check-files?} (default: @code{#t})
15240 Whether to check for updates of the files corresponding to
15243 For instance, when @var{database} is @code{hosts}, setting this flag
15244 instructs nscd to check for updates in @file{/etc/hosts} and to take
15247 @item @code{persistent?} (default: @code{#t})
15248 Whether the cache should be stored persistently on disk.
15250 @item @code{shared?} (default: @code{#t})
15251 Whether the cache should be shared among users.
15253 @item @code{max-database-size} (default: 32@tie{}MiB)
15254 Maximum size in bytes of the database cache.
15256 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
15257 @c settings, so leave them out.
15262 @defvr {Scheme Variable} %nscd-default-caches
15263 List of @code{<nscd-cache>} objects used by default by
15264 @code{nscd-configuration} (see above).
15266 It enables persistent and aggressive caching of service and host name
15267 lookups. The latter provides better host name lookup performance,
15268 resilience in the face of unreliable name servers, and also better
15269 privacy---often the result of host name lookups is in local cache, so
15270 external name servers do not even need to be queried.
15273 @anchor{syslog-configuration-type}
15276 @deftp {Data Type} syslog-configuration
15277 This data type represents the configuration of the syslog daemon.
15280 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
15281 The syslog daemon to use.
15283 @item @code{config-file} (default: @code{%default-syslog.conf})
15284 The syslog configuration file to use.
15289 @anchor{syslog-service}
15291 @deffn {Scheme Procedure} syslog-service @var{config}
15292 Return a service that runs a syslog daemon according to @var{config}.
15294 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
15295 information on the configuration file syntax.
15298 @defvr {Scheme Variable} guix-service-type
15299 This is the type of the service that runs the build daemon,
15300 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
15301 @code{guix-configuration} record as described below.
15304 @anchor{guix-configuration-type}
15305 @deftp {Data Type} guix-configuration
15306 This data type represents the configuration of the Guix build daemon.
15307 @xref{Invoking guix-daemon}, for more information.
15310 @item @code{guix} (default: @var{guix})
15311 The Guix package to use.
15313 @item @code{build-group} (default: @code{"guixbuild"})
15314 Name of the group for build user accounts.
15316 @item @code{build-accounts} (default: @code{10})
15317 Number of build user accounts to create.
15319 @item @code{authorize-key?} (default: @code{#t})
15320 @cindex substitutes, authorization thereof
15321 Whether to authorize the substitute keys listed in
15322 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
15323 (@pxref{Substitutes}).
15325 When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
15326 changed by invoking @command{guix archive --authorize}. You must
15327 instead adjust @code{guix-configuration} as you wish and reconfigure the
15328 system. This ensures that your operating system configuration file is
15332 When booting or reconfiguring to a system where @code{authorize-key?}
15333 is true, the existing @file{/etc/guix/acl} file is backed up as
15334 @file{/etc/guix/acl.bak} if it was determined to be a manually modified
15335 file. This is to facilitate migration from earlier versions, which
15336 allowed for in-place modifications to @file{/etc/guix/acl}.
15339 @vindex %default-authorized-guix-keys
15340 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
15341 The list of authorized key files for archive imports, as a list of
15342 string-valued gexps (@pxref{Invoking guix archive}). By default, it
15343 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
15344 See @code{substitute-urls} below for an example on how to change it.
15346 @item @code{use-substitutes?} (default: @code{#t})
15347 Whether to use substitutes.
15349 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
15350 The list of URLs where to look for substitutes by default.
15352 Suppose you would like to fetch substitutes from @code{guix.example.org}
15353 in addition to @code{@value{SUBSTITUTE-SERVER}}. You will need to do
15354 two things: (1) add @code{guix.example.org} to @code{substitute-urls},
15355 and (2) authorize its signing key, having done appropriate checks
15356 (@pxref{Substitute Server Authorization}). The configuration below does
15360 (guix-configuration
15362 (append (list "https://guix.example.org")
15363 %default-substitute-urls))
15365 (append (list (local-file "./guix.example.org-key.pub"))
15366 %default-authorized-guix-keys)))
15369 This example assumes that the file @file{./guix.example.org-key.pub}
15370 contains the public key that @code{guix.example.org} uses to sign
15373 @item @code{max-silent-time} (default: @code{0})
15374 @itemx @code{timeout} (default: @code{0})
15375 The number of seconds of silence and the number of seconds of activity,
15376 respectively, after which a build process times out. A value of zero
15377 disables the timeout.
15379 @item @code{log-compression} (default: @code{'bzip2})
15380 The type of compression used for build logs---one of @code{gzip},
15381 @code{bzip2}, or @code{none}.
15383 @item @code{discover?} (default: @code{#f})
15384 Whether to discover substitute servers on the local network using mDNS
15387 @item @code{extra-options} (default: @code{'()})
15388 List of extra command-line options for @command{guix-daemon}.
15390 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
15391 File where @command{guix-daemon}'s standard output and standard error
15394 @cindex HTTP proxy, for @code{guix-daemon}
15395 @cindex proxy, for @code{guix-daemon} HTTP access
15396 @item @code{http-proxy} (default: @code{#f})
15397 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
15398 derivations and substitutes.
15400 It is also possible to change the daemon's proxy at run time through the
15401 @code{set-http-proxy} action, which restarts it:
15404 herd set-http-proxy guix-daemon http://localhost:8118
15407 To clear the proxy settings, run:
15410 herd set-http-proxy guix-daemon
15413 @item @code{tmpdir} (default: @code{#f})
15414 A directory path where the @command{guix-daemon} will perform builds.
15419 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
15420 Run @var{udev}, which populates the @file{/dev} directory dynamically.
15421 udev rules can be provided as a list of files through the @var{rules}
15422 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
15423 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
15424 creation of such rule files.
15426 The @command{herd rules udev} command, as root, returns the name of the
15427 directory containing all the active udev rules.
15430 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
15431 Return a udev-rule file named @var{file-name} containing the rules
15432 defined by the @var{contents} literal.
15434 In the following example, a rule for a USB device is defined to be
15435 stored in the file @file{90-usb-thing.rules}. The rule runs a script
15436 upon detecting a USB device with a given product identifier.
15439 (define %example-udev-rule
15441 "90-usb-thing.rules"
15442 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
15443 "ATTR@{product@}==\"Example\", "
15444 "RUN+=\"/path/to/script\"")))
15448 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
15449 [#:groups @var{groups}]
15450 Return a service that extends @code{udev-service-type } with @var{rules}
15451 and @code{account-service-type} with @var{groups} as system groups.
15452 This works by creating a singleton service type
15453 @code{@var{name}-udev-rules}, of which the returned service is an
15456 Here we show how it can be used to extend @code{udev-service-type} with the
15457 previously defined rule @code{%example-udev-rule}.
15463 (cons (udev-rules-service 'usb-thing %example-udev-rule)
15464 %desktop-services)))
15468 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
15469 Return a udev file named @var{file-name} containing the rules defined
15470 within @var{file}, a file-like object.
15472 The following example showcases how we can use an existing rule file.
15475 (use-modules (guix download) ;for url-fetch
15476 (guix packages) ;for origin
15479 (define %android-udev-rules
15481 "51-android-udev.rules"
15482 (let ((version "20170910"))
15485 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
15486 "android-udev-rules/" version "/51-android.rules"))
15488 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
15492 Additionally, Guix package definitions can be included in @var{rules} in
15493 order to extend the udev rules with the definitions found under their
15494 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
15495 @var{file->udev-rule} example, we could have used the
15496 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
15497 packages android)} module.
15499 The following example shows how to use the @var{android-udev-rules}
15500 package so that the Android tool @command{adb} can detect devices
15501 without root privileges. It also details how to create the
15502 @code{adbusers} group, which is required for the proper functioning of
15503 the rules defined within the @code{android-udev-rules} package. To
15504 create such a group, we must define it both as part of the
15505 @code{supplementary-groups} of our @code{user-account} declaration, as
15506 well as in the @var{groups} of the @code{udev-rules-service} procedure.
15509 (use-modules (gnu packages android) ;for android-udev-rules
15510 (gnu system shadow) ;for user-group
15515 (users (cons (user-account
15517 (supplementary-groups
15518 '("adbusers" ;for adb
15519 "wheel" "netdev" "audio" "video")))))
15522 (cons (udev-rules-service 'android android-udev-rules
15523 #:groups '("adbusers"))
15524 %desktop-services)))
15527 @defvr {Scheme Variable} urandom-seed-service-type
15528 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
15529 when rebooting. It also tries to seed @file{/dev/urandom} from
15530 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
15534 @defvr {Scheme Variable} %random-seed-file
15535 This is the name of the file where some random bytes are saved by
15536 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
15537 It defaults to @file{/var/lib/random-seed}.
15542 @defvr {Scheme Variable} gpm-service-type
15543 This is the type of the service that runs GPM, the @dfn{general-purpose
15544 mouse daemon}, which provides mouse support to the Linux console. GPM
15545 allows users to use the mouse in the console, notably to select, copy,
15548 The value for services of this type must be a @code{gpm-configuration}
15549 (see below). This service is not part of @code{%base-services}.
15552 @deftp {Data Type} gpm-configuration
15553 Data type representing the configuration of GPM.
15556 @item @code{options} (default: @code{%default-gpm-options})
15557 Command-line options passed to @command{gpm}. The default set of
15558 options instruct @command{gpm} to listen to mouse events on
15559 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
15562 @item @code{gpm} (default: @code{gpm})
15563 The GPM package to use.
15568 @anchor{guix-publish-service-type}
15569 @deffn {Scheme Variable} guix-publish-service-type
15570 This is the service type for @command{guix publish} (@pxref{Invoking
15571 guix publish}). Its value must be a @code{guix-publish-configuration}
15572 object, as described below.
15574 This assumes that @file{/etc/guix} already contains a signing key pair as
15575 created by @command{guix archive --generate-key} (@pxref{Invoking guix
15576 archive}). If that is not the case, the service will fail to start.
15579 @deftp {Data Type} guix-publish-configuration
15580 Data type representing the configuration of the @code{guix publish}
15584 @item @code{guix} (default: @code{guix})
15585 The Guix package to use.
15587 @item @code{port} (default: @code{80})
15588 The TCP port to listen for connections.
15590 @item @code{host} (default: @code{"localhost"})
15591 The host (and thus, network interface) to listen to. Use
15592 @code{"0.0.0.0"} to listen on all the network interfaces.
15594 @item @code{advertise?} (default: @code{#f})
15595 When true, advertise the service on the local network @i{via} the DNS-SD
15596 protocol, using Avahi.
15598 This allows neighboring Guix devices with discovery on (see
15599 @code{guix-configuration} above) to discover this @command{guix publish}
15600 instance and to automatically download substitutes from it.
15602 @item @code{compression} (default: @code{'(("gzip" 3))})
15603 This is a list of compression method/level tuple used when compressing
15604 substitutes. For example, to compress all substitutes with @emph{both} lzip
15605 at level 7 and gzip at level 9, write:
15608 '(("lzip" 7) ("gzip" 9))
15611 Level 9 achieves the best compression ratio at the expense of increased CPU
15612 usage, whereas level 1 achieves fast compression. @xref{Invoking guix
15613 publish}, for more information on the available compression methods and
15614 the tradeoffs involved.
15616 An empty list disables compression altogether.
15618 @item @code{nar-path} (default: @code{"nar"})
15619 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
15620 publish, @option{--nar-path}}, for details.
15622 @item @code{cache} (default: @code{#f})
15623 When it is @code{#f}, disable caching and instead generate archives on
15624 demand. Otherwise, this should be the name of a directory---e.g.,
15625 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
15626 archives and meta-data ready to be sent. @xref{Invoking guix publish,
15627 @option{--cache}}, for more information on the tradeoffs involved.
15629 @item @code{workers} (default: @code{#f})
15630 When it is an integer, this is the number of worker threads used for
15631 caching; when @code{#f}, the number of processors is used.
15632 @xref{Invoking guix publish, @option{--workers}}, for more information.
15634 @item @code{cache-bypass-threshold} (default: 10 MiB)
15635 When @code{cache} is true, this is the maximum size in bytes of a store
15636 item for which @command{guix publish} may bypass its cache in case of a
15637 cache miss. @xref{Invoking guix publish,
15638 @option{--cache-bypass-threshold}}, for more information.
15640 @item @code{ttl} (default: @code{#f})
15641 When it is an integer, this denotes the @dfn{time-to-live} in seconds
15642 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
15643 for more information.
15647 @anchor{rngd-service}
15648 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
15649 [#:device "/dev/hwrng"]
15650 Return a service that runs the @command{rngd} program from @var{rng-tools}
15651 to add @var{device} to the kernel's entropy pool. The service will fail if
15652 @var{device} does not exist.
15655 @anchor{pam-limits-service}
15656 @cindex session limits
15662 @cindex open file descriptors
15663 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
15665 Return a service that installs a configuration file for the
15666 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
15667 @code{pam_limits} module}. The procedure optionally takes a list of
15668 @code{pam-limits-entry} values, which can be used to specify
15669 @code{ulimit} limits and @code{nice} priority limits to user sessions.
15671 The following limits definition sets two hard and soft limits for all
15672 login sessions of users in the @code{realtime} group:
15675 (pam-limits-service
15677 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
15678 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
15681 The first entry increases the maximum realtime priority for
15682 non-privileged processes; the second entry lifts any restriction of the
15683 maximum address space that can be locked in memory. These settings are
15684 commonly used for real-time audio systems.
15686 Another useful example is raising the maximum number of open file
15687 descriptors that can be used:
15690 (pam-limits-service
15692 (pam-limits-entry "*" 'both 'nofile 100000)))
15695 In the above example, the asterisk means the limit should apply to any
15696 user. It is important to ensure the chosen value doesn't exceed the
15697 maximum system value visible in the @file{/proc/sys/fs/file-max} file,
15698 else the users would be prevented from login in. For more information
15699 about the Pluggable Authentication Module (PAM) limits, refer to the
15700 @samp{pam_limits} man page from the @code{linux-pam} package.
15703 @node Scheduled Job Execution
15704 @subsection Scheduled Job Execution
15708 @cindex scheduling jobs
15709 The @code{(gnu services mcron)} module provides an interface to
15710 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
15711 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
15712 Unix @command{cron} daemon; the main difference is that it is
15713 implemented in Guile Scheme, which provides a lot of flexibility when
15714 specifying the scheduling of jobs and their actions.
15716 The example below defines an operating system that runs the
15717 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
15718 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
15719 well as the @command{mkid} command on behalf of an unprivileged user
15720 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
15721 gexps to introduce job definitions that are passed to mcron
15722 (@pxref{G-Expressions}).
15725 (use-modules (guix) (gnu) (gnu services mcron))
15726 (use-package-modules base idutils)
15728 (define updatedb-job
15729 ;; Run 'updatedb' at 3AM every day. Here we write the
15730 ;; job's action as a Scheme procedure.
15731 #~(job '(next-hour '(3))
15733 (execl (string-append #$findutils "/bin/updatedb")
15735 "--prunepaths=/tmp /var/tmp /gnu/store"))))
15737 (define garbage-collector-job
15738 ;; Collect garbage 5 minutes after midnight every day.
15739 ;; The job's action is a shell command.
15740 #~(job "5 0 * * *" ;Vixie cron syntax
15743 (define idutils-job
15744 ;; Update the index database as user "charlie" at 12:15PM
15745 ;; and 19:15PM. This runs from the user's home directory.
15746 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
15747 (string-append #$idutils "/bin/mkid src")
15753 ;; %BASE-SERVICES already includes an instance of
15754 ;; 'mcron-service-type', which we extend with additional
15755 ;; jobs using 'simple-service'.
15756 (services (cons (simple-service 'my-cron-jobs
15758 (list garbage-collector-job
15764 For more complex jobs defined in Scheme where you need control over the top
15765 level, for instance to introduce a @code{use-modules} form, you can move your
15766 code to a separate program using the @code{program-file} procedure of the
15767 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
15771 (define %battery-alert-job
15772 ;; Beep when the battery percentage falls below %MIN-LEVEL.
15774 '(next-minute (range 0 60 1))
15776 "battery-alert.scm"
15777 (with-imported-modules (source-module-closure
15778 '((guix build utils)))
15780 (use-modules (guix build utils)
15783 (ice-9 textual-ports)
15786 (define %min-level 20)
15788 (setenv "LC_ALL" "C") ;ensure English output
15789 (and-let* ((input-pipe (open-pipe*
15791 #$(file-append acpi "/bin/acpi")))
15792 (output (get-string-all input-pipe))
15793 (m (string-match "Discharging, ([0-9]+)%" output))
15794 (level (string->number (match:substring m 1)))
15795 ((< level %min-level)))
15796 (format #t "warning: Battery level is low (~a%)~%" level)
15797 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
15800 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
15801 for more information on mcron job specifications. Below is the
15802 reference of the mcron service.
15804 On a running system, you can use the @code{schedule} action of the service to
15805 visualize the mcron jobs that will be executed next:
15808 # herd schedule mcron
15812 The example above lists the next five tasks that will be executed, but you can
15813 also specify the number of tasks to display:
15816 # herd schedule mcron 10
15819 @defvr {Scheme Variable} mcron-service-type
15820 This is the type of the @code{mcron} service, whose value is an
15821 @code{mcron-configuration} object.
15823 This service type can be the target of a service extension that provides
15824 it additional job specifications (@pxref{Service Composition}). In
15825 other words, it is possible to define services that provide additional
15829 @deftp {Data Type} mcron-configuration
15830 Data type representing the configuration of mcron.
15833 @item @code{mcron} (default: @var{mcron})
15834 The mcron package to use.
15837 This is a list of gexps (@pxref{G-Expressions}), where each gexp
15838 corresponds to an mcron job specification (@pxref{Syntax, mcron job
15839 specifications,, mcron, GNU@tie{}mcron}).
15845 @subsection Log Rotation
15848 @cindex log rotation
15850 Log files such as those found in @file{/var/log} tend to grow endlessly,
15851 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
15852 their contents in separate files, possibly compressed. The @code{(gnu
15853 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
15854 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
15856 This service is part of @code{%base-services}, and thus enabled by
15857 default, with the default settings, for commonly encountered log files.
15858 The example below shows how to extend it with an additional
15859 @dfn{rotation}, should you need to do that (usually, services that
15860 produce log files already take care of that):
15863 (use-modules (guix) (gnu))
15864 (use-service-modules admin)
15866 (define my-log-files
15867 ;; Log files that I want to rotate.
15868 '("/var/log/something.log" "/var/log/another.log"))
15872 (services (cons (simple-service 'rotate-my-stuff
15873 rottlog-service-type
15874 (list (log-rotation
15876 (files my-log-files))))
15880 @defvr {Scheme Variable} rottlog-service-type
15881 This is the type of the Rottlog service, whose value is a
15882 @code{rottlog-configuration} object.
15884 Other services can extend this one with new @code{log-rotation} objects
15885 (see below), thereby augmenting the set of files to be rotated.
15887 This service type can define mcron jobs (@pxref{Scheduled Job
15888 Execution}) to run the rottlog service.
15891 @deftp {Data Type} rottlog-configuration
15892 Data type representing the configuration of rottlog.
15895 @item @code{rottlog} (default: @code{rottlog})
15896 The Rottlog package to use.
15898 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
15899 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
15900 rottlog, GNU Rot[t]log Manual}).
15902 @item @code{rotations} (default: @code{%default-rotations})
15903 A list of @code{log-rotation} objects as defined below.
15906 This is a list of gexps where each gexp corresponds to an mcron job
15907 specification (@pxref{Scheduled Job Execution}).
15911 @deftp {Data Type} log-rotation
15912 Data type representing the rotation of a group of log files.
15914 Taking an example from the Rottlog manual (@pxref{Period Related File
15915 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
15921 (files '("/var/log/apache/*"))
15922 (options '("storedir apache-archives"
15928 The list of fields is as follows:
15931 @item @code{frequency} (default: @code{'weekly})
15932 The log rotation frequency, a symbol.
15935 The list of files or file glob patterns to rotate.
15937 @item @code{options} (default: @code{'()})
15938 The list of rottlog options for this rotation (@pxref{Configuration
15939 parameters,,, rottlog, GNU Rot[t]lg Manual}).
15941 @item @code{post-rotate} (default: @code{#f})
15942 Either @code{#f} or a gexp to execute once the rotation has completed.
15946 @defvr {Scheme Variable} %default-rotations
15947 Specifies weekly rotation of @code{%rotated-files} and of
15948 @file{/var/log/guix-daemon.log}.
15951 @defvr {Scheme Variable} %rotated-files
15952 The list of syslog-controlled files to be rotated. By default it is:
15953 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
15954 "/var/log/maillog")}.
15957 @node Networking Services
15958 @subsection Networking Services
15960 The @code{(gnu services networking)} module provides services to configure
15961 the network interface.
15963 @cindex DHCP, networking service
15964 @defvr {Scheme Variable} dhcp-client-service-type
15965 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
15966 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
15967 is the DHCP client package to use, @code{isc-dhcp} by default.
15970 @deffn {Scheme Procedure} dhcpd-service-type
15971 This type defines a service that runs a DHCP daemon. To create a
15972 service of this type, you must supply a @code{<dhcpd-configuration>}.
15976 (service dhcpd-service-type
15977 (dhcpd-configuration
15978 (config-file (local-file "my-dhcpd.conf"))
15979 (interfaces '("enp0s25"))))
15983 @deftp {Data Type} dhcpd-configuration
15985 @item @code{package} (default: @code{isc-dhcp})
15986 The package that provides the DHCP daemon. This package is expected to
15987 provide the daemon at @file{sbin/dhcpd} relative to its output
15988 directory. The default package is the
15989 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
15990 @item @code{config-file} (default: @code{#f})
15991 The configuration file to use. This is required. It will be passed to
15992 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
15993 object (@pxref{G-Expressions, file-like objects}). See @code{man
15994 dhcpd.conf} for details on the configuration file syntax.
15995 @item @code{version} (default: @code{"4"})
15996 The DHCP version to use. The ISC DHCP server supports the values ``4'',
15997 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
15998 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
16000 @item @code{run-directory} (default: @code{"/run/dhcpd"})
16001 The run directory to use. At service activation time, this directory
16002 will be created if it does not exist.
16003 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
16004 The PID file to use. This corresponds to the @code{-pf} option of
16005 @code{dhcpd}. See @code{man dhcpd} for details.
16006 @item @code{interfaces} (default: @code{'()})
16007 The names of the network interfaces on which dhcpd should listen for
16008 broadcasts. If this list is not empty, then its elements (which must be
16009 strings) will be appended to the @code{dhcpd} invocation when starting
16010 the daemon. It may not be necessary to explicitly specify any
16011 interfaces here; see @code{man dhcpd} for details.
16015 @defvr {Scheme Variable} static-networking-service-type
16016 This is the type for statically-configured network interfaces.
16017 @c TODO Document <static-networking> data structures.
16020 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
16021 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
16022 [#:requirement @code{'(udev)}]
16023 Return a service that starts @var{interface} with address @var{ip}. If
16024 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
16025 it must be a string specifying the default network gateway. @var{requirement}
16026 can be used to declare a dependency on another service before configuring the
16029 This procedure can be called several times, one for each network
16030 interface of interest. Behind the scenes what it does is extend
16031 @code{static-networking-service-type} with additional network interfaces
16037 (static-networking-service "eno1" "192.168.1.82"
16038 #:gateway "192.168.1.2"
16039 #:name-servers '("192.168.1.2"))
16046 @cindex network management
16047 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
16048 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
16049 management daemon that aims to simplify wired and wireless networking.
16051 This service adds the @var{wicd} package to the global profile, providing
16052 several commands to interact with the daemon and configure networking:
16053 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
16054 and @command{wicd-curses} user interfaces.
16057 @cindex ModemManager
16059 @defvr {Scheme Variable} modem-manager-service-type
16060 This is the service type for the
16061 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
16062 service. The value for this service type is a
16063 @code{modem-manager-configuration} record.
16065 This service is part of @code{%desktop-services} (@pxref{Desktop
16069 @deftp {Data Type} modem-manager-configuration
16070 Data type representing the configuration of ModemManager.
16073 @item @code{modem-manager} (default: @code{modem-manager})
16074 The ModemManager package to use.
16079 @cindex USB_ModeSwitch
16080 @cindex Modeswitching
16082 @defvr {Scheme Variable} usb-modeswitch-service-type
16083 This is the service type for the
16084 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch}
16085 service. The value for this service type is
16086 a @code{usb-modeswitch-configuration} record.
16088 When plugged in, some USB modems (and other USB devices) initially present
16089 themselves as a read-only storage medium and not as a modem. They need to be
16090 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
16091 installs udev rules to automatically modeswitch these devices when they are
16094 This service is part of @code{%desktop-services} (@pxref{Desktop
16098 @deftp {Data Type} usb-modeswitch-configuration
16099 Data type representing the configuration of USB_ModeSwitch.
16102 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
16103 The USB_ModeSwitch package providing the binaries for modeswitching.
16105 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
16106 The package providing the device data and udev rules file used by
16109 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
16110 Which config file to use for the USB_ModeSwitch dispatcher. By default the
16111 config file shipped with USB_ModeSwitch is used which disables logging to
16112 @file{/var/log} among other default settings. If set to @code{#f}, no config
16118 @cindex NetworkManager
16120 @defvr {Scheme Variable} network-manager-service-type
16121 This is the service type for the
16122 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
16123 service. The value for this service type is a
16124 @code{network-manager-configuration} record.
16126 This service is part of @code{%desktop-services} (@pxref{Desktop
16130 @deftp {Data Type} network-manager-configuration
16131 Data type representing the configuration of NetworkManager.
16134 @item @code{network-manager} (default: @code{network-manager})
16135 The NetworkManager package to use.
16137 @item @code{dns} (default: @code{"default"})
16138 Processing mode for DNS, which affects how NetworkManager uses the
16139 @code{resolv.conf} configuration file.
16143 NetworkManager will update @code{resolv.conf} to reflect the nameservers
16144 provided by currently active connections.
16147 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
16148 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
16149 then update @code{resolv.conf} to point to the local nameserver.
16151 With this setting, you can share your network connection. For example when
16152 you want to share your network connection to another laptop @i{via} an
16153 Ethernet cable, you can open @command{nm-connection-editor} and configure the
16154 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
16155 and reestablish the connection (or reboot).
16157 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
16158 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
16159 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
16160 browser on your host system, or connect to the VM @i{via} SSH
16161 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
16162 host-to-guest connection, run this command once:
16165 nmcli connection add type tun \
16166 connection.interface-name tap0 \
16167 tun.mode tap tun.owner $(id -u) \
16168 ipv4.method shared \
16169 ipv4.addresses 172.28.112.1/24
16172 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
16173 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
16174 @command{qemu-system-...}.
16177 NetworkManager will not modify @code{resolv.conf}.
16180 @item @code{vpn-plugins} (default: @code{'()})
16181 This is the list of available plugins for virtual private networks
16182 (VPNs). An example of this is the @code{network-manager-openvpn}
16183 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
16189 @deffn {Scheme Variable} connman-service-type
16190 This is the service type to run @url{https://01.org/connman,Connman},
16191 a network connection manager.
16193 Its value must be an
16194 @code{connman-configuration} record as in this example:
16197 (service connman-service-type
16198 (connman-configuration
16199 (disable-vpn? #t)))
16202 See below for details about @code{connman-configuration}.
16205 @deftp {Data Type} connman-configuration
16206 Data Type representing the configuration of connman.
16209 @item @code{connman} (default: @var{connman})
16210 The connman package to use.
16212 @item @code{disable-vpn?} (default: @code{#f})
16213 When true, disable connman's vpn plugin.
16217 @cindex WPA Supplicant
16218 @defvr {Scheme Variable} wpa-supplicant-service-type
16219 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
16220 supplicant}, an authentication daemon required to authenticate against
16221 encrypted WiFi or ethernet networks.
16224 @deftp {Data Type} wpa-supplicant-configuration
16225 Data type representing the configuration of WPA Supplicant.
16227 It takes the following parameters:
16230 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
16231 The WPA Supplicant package to use.
16233 @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
16234 List of services that should be started before WPA Supplicant starts.
16236 @item @code{dbus?} (default: @code{#t})
16237 Whether to listen for requests on D-Bus.
16239 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
16240 Where to store the PID file.
16242 @item @code{interface} (default: @code{#f})
16243 If this is set, it must specify the name of a network interface that
16244 WPA supplicant will control.
16246 @item @code{config-file} (default: @code{#f})
16247 Optional configuration file to use.
16249 @item @code{extra-options} (default: @code{'()})
16250 List of additional command-line arguments to pass to the daemon.
16254 @cindex hostapd service, for Wi-Fi access points
16255 @cindex Wi-Fi access points, hostapd service
16256 @defvr {Scheme Variable} hostapd-service-type
16257 This is the service type to run the @uref{https://w1.fi/hostapd/,
16258 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
16259 authentication servers. Its associated value must be a
16260 @code{hostapd-configuration} as shown below:
16263 ;; Use wlan1 to run the access point for "My Network".
16264 (service hostapd-service-type
16265 (hostapd-configuration
16266 (interface "wlan1")
16267 (ssid "My Network")
16272 @deftp {Data Type} hostapd-configuration
16273 This data type represents the configuration of the hostapd service, with
16274 the following fields:
16277 @item @code{package} (default: @code{hostapd})
16278 The hostapd package to use.
16280 @item @code{interface} (default: @code{"wlan0"})
16281 The network interface to run the WiFi access point.
16284 The SSID (@dfn{service set identifier}), a string that identifies this
16287 @item @code{broadcast-ssid?} (default: @code{#t})
16288 Whether to broadcast this SSID.
16290 @item @code{channel} (default: @code{1})
16291 The WiFi channel to use.
16293 @item @code{driver} (default: @code{"nl80211"})
16294 The driver interface type. @code{"nl80211"} is used with all Linux
16295 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
16296 RADIUS server that does # not control any wireless/wired driver.
16298 @item @code{extra-settings} (default: @code{""})
16299 Extra settings to append as-is to the hostapd configuration file. See
16300 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
16301 configuration file reference.
16305 @defvr {Scheme Variable} simulated-wifi-service-type
16306 This is the type of a service to simulate WiFi networking, which can be
16307 useful in virtual machines for testing purposes. The service loads the
16309 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
16310 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
16311 network that can be seen on @code{wlan0}, by default.
16313 The service's value is a @code{hostapd-configuration} record.
16317 @defvr {Scheme Variable} iptables-service-type
16318 This is the service type to set up an iptables configuration. iptables is a
16319 packet filtering framework supported by the Linux kernel. This service
16320 supports configuring iptables for both IPv4 and IPv6. A simple example
16321 configuration rejecting all incoming connections except those to the ssh port
16325 (service iptables-service-type
16326 (iptables-configuration
16327 (ipv4-rules (plain-file "iptables.rules" "*filter
16331 -A INPUT -p tcp --dport 22 -j ACCEPT
16332 -A INPUT -j REJECT --reject-with icmp-port-unreachable
16335 (ipv6-rules (plain-file "ip6tables.rules" "*filter
16339 -A INPUT -p tcp --dport 22 -j ACCEPT
16340 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
16346 @deftp {Data Type} iptables-configuration
16347 The data type representing the configuration of iptables.
16350 @item @code{iptables} (default: @code{iptables})
16351 The iptables package that provides @code{iptables-restore} and
16352 @code{ip6tables-restore}.
16353 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
16354 The iptables rules to use. It will be passed to @code{iptables-restore}.
16355 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
16357 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
16358 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
16359 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
16365 @defvr {Scheme Variable} nftables-service-type
16366 This is the service type to set up a nftables configuration. nftables is a
16367 netfilter project that aims to replace the existing iptables, ip6tables,
16368 arptables and ebtables framework. It provides a new packet filtering
16369 framework, a new user-space utility @command{nft}, and a compatibility layer
16370 for iptables. This service comes with a default ruleset
16371 @code{%default-nftables-ruleset} that rejecting all incomming connections
16372 except those to the ssh port 22. To use it, simply write:
16375 (service nftables-service-type)
16379 @deftp {Data Type} nftables-configuration
16380 The data type representing the configuration of nftables.
16383 @item @code{package} (default: @code{nftables})
16384 The nftables package that provides @command{nft}.
16385 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
16386 The nftables ruleset to use. This may be any ``file-like'' object
16387 (@pxref{G-Expressions, file-like objects}).
16391 @cindex NTP (Network Time Protocol), service
16392 @cindex ntpd, service for the Network Time Protocol daemon
16393 @cindex real time clock
16394 @defvr {Scheme Variable} ntp-service-type
16395 This is the type of the service running the @uref{https://www.ntp.org,
16396 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
16397 system clock synchronized with that of the specified NTP servers.
16399 The value of this service is an @code{ntpd-configuration} object, as described
16403 @deftp {Data Type} ntp-configuration
16404 This is the data type for the NTP service configuration.
16407 @item @code{servers} (default: @code{%ntp-servers})
16408 This is the list of servers (@code{<ntp-server>} records) with which
16409 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
16412 @item @code{allow-large-adjustment?} (default: @code{#t})
16413 This determines whether @command{ntpd} is allowed to make an initial
16414 adjustment of more than 1,000 seconds.
16416 @item @code{ntp} (default: @code{ntp})
16417 The NTP package to use.
16421 @defvr {Scheme Variable} %ntp-servers
16422 List of host names used as the default NTP servers. These are servers of the
16423 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
16426 @deftp {Data Type} ntp-server
16427 The data type representing the configuration of a NTP server.
16430 @item @code{type} (default: @code{'server})
16431 The type of the NTP server, given as a symbol. One of @code{'pool},
16432 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
16434 @item @code{address}
16435 The address of the server, as a string.
16437 @item @code{options}
16438 NTPD options to use with that specific server, given as a list of option names
16439 and/or of option names and values tuples. The following example define a server
16440 to use with the options @option{iburst} and @option{prefer}, as well as
16441 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
16446 (address "some.ntp.server.org")
16447 (options `(iburst (version 3) (maxpoll 16) prefer))))
16453 @deffn {Scheme Procedure} openntpd-service-type
16454 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
16455 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
16456 clock synchronized with that of the given servers.
16460 openntpd-service-type
16461 (openntpd-configuration
16462 (listen-on '("127.0.0.1" "::1"))
16463 (sensor '("udcf0 correction 70000"))
16464 (constraint-from '("www.gnu.org"))
16465 (constraints-from '("https://www.google.com/"))))
16470 @defvr {Scheme Variable} %openntpd-servers
16471 This variable is a list of the server addresses defined in
16472 @code{%ntp-servers}.
16475 @deftp {Data Type} openntpd-configuration
16477 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
16478 The openntpd executable to use.
16479 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
16480 A list of local IP addresses or hostnames the ntpd daemon should listen on.
16481 @item @code{query-from} (default: @code{'()})
16482 A list of local IP address the ntpd daemon should use for outgoing queries.
16483 @item @code{sensor} (default: @code{'()})
16484 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
16485 will listen to each sensor that actually exists and ignore non-existent ones.
16486 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
16488 @item @code{server} (default: @code{'()})
16489 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
16490 @item @code{servers} (default: @code{%openntp-servers})
16491 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
16492 @item @code{constraint-from} (default: @code{'()})
16493 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
16494 This time information is not used for precision but acts as an authenticated
16495 constraint, thereby reducing the impact of unauthenticated NTP
16496 man-in-the-middle attacks.
16497 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
16499 @item @code{constraints-from} (default: @code{'()})
16500 As with constraint from, specify a list of URLs, IP addresses or hostnames of
16501 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
16502 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
16507 @deffn {Scheme variable} inetd-service-type
16508 This service runs the @command{inetd} (@pxref{inetd invocation,,,
16509 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
16510 connections on internet sockets, and lazily starts the specified server
16511 program when a connection is made on one of these sockets.
16513 The value of this service is an @code{inetd-configuration} object. The
16514 following example configures the @command{inetd} daemon to provide the
16515 built-in @command{echo} service, as well as an smtp service which
16516 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
16517 gateway @code{hostname}:
16522 (inetd-configuration
16526 (socket-type 'stream)
16533 (socket-type 'stream)
16537 (program (file-append openssh "/bin/ssh"))
16539 '("ssh" "-qT" "-i" "/path/to/ssh_key"
16540 "-W" "smtp-server:25" "user@@hostname")))))))
16543 See below for more details about @code{inetd-configuration}.
16546 @deftp {Data Type} inetd-configuration
16547 Data type representing the configuration of @command{inetd}.
16550 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
16551 The @command{inetd} executable to use.
16553 @item @code{entries} (default: @code{'()})
16554 A list of @command{inetd} service entries. Each entry should be created
16555 by the @code{inetd-entry} constructor.
16559 @deftp {Data Type} inetd-entry
16560 Data type representing an entry in the @command{inetd} configuration.
16561 Each entry corresponds to a socket where @command{inetd} will listen for
16565 @item @code{node} (default: @code{#f})
16566 Optional string, a comma-separated list of local addresses
16567 @command{inetd} should use when listening for this service.
16568 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
16569 description of all options.
16571 A string, the name must correspond to an entry in @code{/etc/services}.
16572 @item @code{socket-type}
16573 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
16575 @item @code{protocol}
16576 A string, must correspond to an entry in @code{/etc/protocols}.
16577 @item @code{wait?} (default: @code{#t})
16578 Whether @command{inetd} should wait for the server to exit before
16579 listening to new service requests.
16581 A string containing the user (and, optionally, group) name of the user
16582 as whom the server should run. The group name can be specified in a
16583 suffix, separated by a colon or period, i.e.@: @code{"user"},
16584 @code{"user:group"} or @code{"user.group"}.
16585 @item @code{program} (default: @code{"internal"})
16586 The server program which will serve the requests, or @code{"internal"}
16587 if @command{inetd} should use a built-in service.
16588 @item @code{arguments} (default: @code{'()})
16589 A list strings or file-like objects, which are the server program's
16590 arguments, starting with the zeroth argument, i.e.@: the name of the
16591 program itself. For @command{inetd}'s internal services, this entry
16592 must be @code{'()} or @code{'("internal")}.
16595 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
16596 detailed discussion of each configuration field.
16600 @defvr {Scheme Variable} tor-service-type
16601 This is the type for a service that runs the @uref{https://torproject.org,
16602 Tor} anonymous networking daemon. The service is configured using a
16603 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
16604 @code{tor} unprivileged user, which is a member of the @code{tor} group.
16608 @deftp {Data Type} tor-configuration
16610 @item @code{tor} (default: @code{tor})
16611 The package that provides the Tor daemon. This package is expected to provide
16612 the daemon at @file{bin/tor} relative to its output directory. The default
16613 package is the @uref{https://www.torproject.org, Tor Project's}
16616 @item @code{config-file} (default: @code{(plain-file "empty" "")})
16617 The configuration file to use. It will be appended to a default configuration
16618 file, and the final configuration file will be passed to @code{tor} via its
16619 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
16620 file-like objects}). See @code{man tor} for details on the configuration file
16623 @item @code{hidden-services} (default: @code{'()})
16624 The list of @code{<hidden-service>} records to use. For any hidden service
16625 you include in this list, appropriate configuration to enable the hidden
16626 service will be automatically added to the default configuration file. You
16627 may conveniently create @code{<hidden-service>} records using the
16628 @code{tor-hidden-service} procedure described below.
16630 @item @code{socks-socket-type} (default: @code{'tcp})
16631 The default socket type that Tor should use for its SOCKS socket. This must
16632 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
16633 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
16634 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
16635 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
16638 If you want to customize the SOCKS socket in more detail, leave
16639 @code{socks-socket-type} at its default value of @code{'tcp} and use
16640 @code{config-file} to override the default by providing your own
16641 @code{SocksPort} option.
16643 @item @code{control-socket?} (default: @code{#f})
16644 Whether or not to provide a ``control socket'' by which Tor can be
16645 controlled to, for instance, dynamically instantiate tor onion services.
16646 If @code{#t}, Tor will listen for control commands on the UNIX domain socket
16647 @file{/var/run/tor/control-sock}, which will be made writable by members of the
16653 @cindex hidden service
16654 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
16655 Define a new Tor @dfn{hidden service} called @var{name} and implementing
16656 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
16659 '((22 "127.0.0.1:22")
16660 (80 "127.0.0.1:8080"))
16663 In this example, port 22 of the hidden service is mapped to local port 22, and
16664 port 80 is mapped to local port 8080.
16666 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
16667 the @file{hostname} file contains the @code{.onion} host name for the hidden
16670 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
16671 project's documentation} for more information.
16674 The @code{(gnu services rsync)} module provides the following services:
16676 You might want an rsync daemon if you have files that you want available
16677 so anyone (or just yourself) can download existing files or upload new
16680 @deffn {Scheme Variable} rsync-service-type
16681 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
16682 The value for this service type is a
16683 @command{rsync-configuration} record as in this example:
16686 (service rsync-service-type)
16689 See below for details about @code{rsync-configuration}.
16692 @deftp {Data Type} rsync-configuration
16693 Data type representing the configuration for @code{rsync-service}.
16696 @item @code{package} (default: @var{rsync})
16697 @code{rsync} package to use.
16699 @item @code{port-number} (default: @code{873})
16700 TCP port on which @command{rsync} listens for incoming connections. If port
16701 is less than @code{1024} @command{rsync} needs to be started as the
16702 @code{root} user and group.
16704 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
16705 Name of the file where @command{rsync} writes its PID.
16707 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
16708 Name of the file where @command{rsync} writes its lock file.
16710 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
16711 Name of the file where @command{rsync} writes its log file.
16713 @item @code{use-chroot?} (default: @var{#t})
16714 Whether to use chroot for @command{rsync} shared directory.
16716 @item @code{share-path} (default: @file{/srv/rsync})
16717 Location of the @command{rsync} shared directory.
16719 @item @code{share-comment} (default: @code{"Rsync share"})
16720 Comment of the @command{rsync} shared directory.
16722 @item @code{read-only?} (default: @var{#f})
16723 Read-write permissions to shared directory.
16725 @item @code{timeout} (default: @code{300})
16726 I/O timeout in seconds.
16728 @item @code{user} (default: @var{"root"})
16729 Owner of the @code{rsync} process.
16731 @item @code{group} (default: @var{"root"})
16732 Group of the @code{rsync} process.
16734 @item @code{uid} (default: @var{"rsyncd"})
16735 User name or user ID that file transfers to and from that module should take
16736 place as when the daemon was run as @code{root}.
16738 @item @code{gid} (default: @var{"rsyncd"})
16739 Group name or group ID that will be used when accessing the module.
16744 The @code{(gnu services syncthing)} module provides the following services:
16747 You might want a syncthing daemon if you have files between two or more
16748 computers and want to sync them in real time, safely protected from
16751 @deffn {Scheme Variable} syncthing-service-type
16752 This is the service type for the @uref{https://syncthing.net/,
16753 syncthing} daemon, The value for this service type is a
16754 @command{syncthing-configuration} record as in this example:
16757 (service syncthing-service-type
16758 (syncthing-configuration (user "alice")))
16761 See below for details about @code{syncthing-configuration}.
16763 @deftp {Data Type} syncthing-configuration
16764 Data type representing the configuration for @code{syncthing-service-type}.
16767 @item @code{syncthing} (default: @var{syncthing})
16768 @code{syncthing} package to use.
16770 @item @code{arguments} (default: @var{'()})
16771 List of command-line arguments passing to @code{syncthing} binary.
16773 @item @code{logflags} (default: @var{0})
16774 Sum of loging flags, see
16775 @uref{https://docs.syncthing.net/users/syncthing.html#cmdoption-logflags, Syncthing documentation logflags}.
16777 @item @code{user} (default: @var{#f})
16778 The user as which the Syncthing service is to be run.
16779 This assumes that the specified user exists.
16781 @item @code{group} (default: @var{"users"})
16782 The group as which the Syncthing service is to be run.
16783 This assumes that the specified group exists.
16785 @item @code{home} (default: @var{#f})
16786 Common configuration and data directory. The default configuration
16787 directory is @file{$HOME} of the specified Syncthing @code{user}.
16793 Furthermore, @code{(gnu services ssh)} provides the following services.
16797 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
16798 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
16799 [#:allow-empty-passwords? #f] [#:root-login? #f] @
16800 [#:syslog-output? #t] [#:x11-forwarding? #t] @
16801 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
16802 [#:public-key-authentication? #t] [#:initialize? #t]
16803 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
16804 @var{host-key} must designate a file containing the host key, and readable
16807 When @var{daemonic?} is true, @command{lshd} will detach from the
16808 controlling terminal and log its output to syslogd, unless one sets
16809 @var{syslog-output?} to false. Obviously, it also makes lsh-service
16810 depend on existence of syslogd service. When @var{pid-file?} is true,
16811 @command{lshd} writes its PID to the file called @var{pid-file}.
16813 When @var{initialize?} is true, automatically create the seed and host key
16814 upon service activation if they do not exist yet. This may take long and
16815 require interaction.
16817 When @var{initialize?} is false, it is up to the user to initialize the
16818 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
16819 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
16820 basics,,, lsh, LSH Manual}).
16822 When @var{interfaces} is empty, lshd listens for connections on all the
16823 network interfaces; otherwise, @var{interfaces} must be a list of host names
16826 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
16827 passwords, and @var{root-login?} specifies whether to accept log-ins as
16830 The other options should be self-descriptive.
16835 @deffn {Scheme Variable} openssh-service-type
16836 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
16837 shell daemon, @command{sshd}. Its value must be an
16838 @code{openssh-configuration} record as in this example:
16841 (service openssh-service-type
16842 (openssh-configuration
16843 (x11-forwarding? #t)
16844 (permit-root-login 'without-password)
16846 `(("alice" ,(local-file "alice.pub"))
16847 ("bob" ,(local-file "bob.pub"))))))
16850 See below for details about @code{openssh-configuration}.
16852 This service can be extended with extra authorized keys, as in this
16856 (service-extension openssh-service-type
16857 (const `(("charlie"
16858 ,(local-file "charlie.pub")))))
16862 @deftp {Data Type} openssh-configuration
16863 This is the configuration record for OpenSSH's @command{sshd}.
16866 @item @code{openssh} (default @var{openssh})
16867 The Openssh package to use.
16869 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
16870 Name of the file where @command{sshd} writes its PID.
16872 @item @code{port-number} (default: @code{22})
16873 TCP port on which @command{sshd} listens for incoming connections.
16875 @item @code{permit-root-login} (default: @code{#f})
16876 This field determines whether and when to allow logins as root. If
16877 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
16878 If it's the symbol @code{'without-password}, then root logins are
16879 permitted but not with password-based authentication.
16881 @item @code{allow-empty-passwords?} (default: @code{#f})
16882 When true, users with empty passwords may log in. When false, they may
16885 @item @code{password-authentication?} (default: @code{#t})
16886 When true, users may log in with their password. When false, they have
16887 other authentication methods.
16889 @item @code{public-key-authentication?} (default: @code{#t})
16890 When true, users may log in using public key authentication. When
16891 false, users have to use other authentication method.
16893 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
16894 This is used only by protocol version 2.
16896 @item @code{x11-forwarding?} (default: @code{#f})
16897 When true, forwarding of X11 graphical client connections is
16898 enabled---in other words, @command{ssh} options @option{-X} and
16899 @option{-Y} will work.
16901 @item @code{allow-agent-forwarding?} (default: @code{#t})
16902 Whether to allow agent forwarding.
16904 @item @code{allow-tcp-forwarding?} (default: @code{#t})
16905 Whether to allow TCP forwarding.
16907 @item @code{gateway-ports?} (default: @code{#f})
16908 Whether to allow gateway ports.
16910 @item @code{challenge-response-authentication?} (default: @code{#f})
16911 Specifies whether challenge response authentication is allowed (e.g.@: via
16914 @item @code{use-pam?} (default: @code{#t})
16915 Enables the Pluggable Authentication Module interface. If set to
16916 @code{#t}, this will enable PAM authentication using
16917 @code{challenge-response-authentication?} and
16918 @code{password-authentication?}, in addition to PAM account and session
16919 module processing for all authentication types.
16921 Because PAM challenge response authentication usually serves an
16922 equivalent role to password authentication, you should disable either
16923 @code{challenge-response-authentication?} or
16924 @code{password-authentication?}.
16926 @item @code{print-last-log?} (default: @code{#t})
16927 Specifies whether @command{sshd} should print the date and time of the
16928 last user login when a user logs in interactively.
16930 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
16931 Configures external subsystems (e.g.@: file transfer daemon).
16933 This is a list of two-element lists, each of which containing the
16934 subsystem name and a command (with optional arguments) to execute upon
16937 The command @command{internal-sftp} implements an in-process SFTP
16938 server. Alternatively, one can specify the @command{sftp-server} command:
16940 (service openssh-service-type
16941 (openssh-configuration
16943 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
16946 @item @code{accepted-environment} (default: @code{'()})
16947 List of strings describing which environment variables may be exported.
16949 Each string gets on its own line. See the @code{AcceptEnv} option in
16950 @code{man sshd_config}.
16952 This example allows ssh-clients to export the @env{COLORTERM} variable.
16953 It is set by terminal emulators, which support colors. You can use it in
16954 your shell's resource file to enable colors for the prompt and commands
16955 if this variable is set.
16958 (service openssh-service-type
16959 (openssh-configuration
16960 (accepted-environment '("COLORTERM"))))
16963 @item @code{authorized-keys} (default: @code{'()})
16964 @cindex authorized keys, SSH
16965 @cindex SSH authorized keys
16966 This is the list of authorized keys. Each element of the list is a user
16967 name followed by one or more file-like objects that represent SSH public
16971 (openssh-configuration
16973 `(("rekado" ,(local-file "rekado.pub"))
16974 ("chris" ,(local-file "chris.pub"))
16975 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
16979 registers the specified public keys for user accounts @code{rekado},
16980 @code{chris}, and @code{root}.
16982 Additional authorized keys can be specified @i{via}
16983 @code{service-extension}.
16985 Note that this does @emph{not} interfere with the use of
16986 @file{~/.ssh/authorized_keys}.
16988 @item @code{log-level} (default: @code{'info})
16989 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
16990 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
16991 page for @file{sshd_config} for the full list of level names.
16993 @item @code{extra-content} (default: @code{""})
16994 This field can be used to append arbitrary text to the configuration file. It
16995 is especially useful for elaborate configurations that cannot be expressed
16996 otherwise. This configuration, for example, would generally disable root
16997 logins, but permit them from one specific IP address:
17000 (openssh-configuration
17002 Match Address 192.168.0.1
17003 PermitRootLogin yes"))
17009 @deffn {Scheme Procedure} dropbear-service [@var{config}]
17010 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
17011 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
17014 For example, to specify a Dropbear service listening on port 1234, add
17015 this call to the operating system's @code{services} field:
17018 (dropbear-service (dropbear-configuration
17019 (port-number 1234)))
17023 @deftp {Data Type} dropbear-configuration
17024 This data type represents the configuration of a Dropbear SSH daemon.
17027 @item @code{dropbear} (default: @var{dropbear})
17028 The Dropbear package to use.
17030 @item @code{port-number} (default: 22)
17031 The TCP port where the daemon waits for incoming connections.
17033 @item @code{syslog-output?} (default: @code{#t})
17034 Whether to enable syslog output.
17036 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
17037 File name of the daemon's PID file.
17039 @item @code{root-login?} (default: @code{#f})
17040 Whether to allow @code{root} logins.
17042 @item @code{allow-empty-passwords?} (default: @code{#f})
17043 Whether to allow empty passwords.
17045 @item @code{password-authentication?} (default: @code{#t})
17046 Whether to enable password-based authentication.
17051 @deffn {Scheme Variable} autossh-service-type
17052 This is the type for the @uref{https://www.harding.motd.ca/autossh,
17053 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
17054 restarting it as necessary should it die or stop passing traffic.
17055 AutoSSH can be run manually from the command-line by passing arguments
17056 to the binary @command{autossh} from the package @code{autossh}, but it
17057 can also be run as a Guix service. This latter use case is documented
17060 AutoSSH can be used to forward local traffic to a remote machine using
17061 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
17064 For example, to specify a service running autossh as the user
17065 @code{pino} and forwarding all local connections to port @code{8081} to
17066 @code{remote:8081} using an SSH tunnel, add this call to the operating
17067 system's @code{services} field:
17070 (service autossh-service-type
17071 (autossh-configuration
17073 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
17077 @deftp {Data Type} autossh-configuration
17078 This data type represents the configuration of an AutoSSH service.
17082 @item @code{user} (default @code{"autossh"})
17083 The user as which the AutoSSH service is to be run.
17084 This assumes that the specified user exists.
17086 @item @code{poll} (default @code{600})
17087 Specifies the connection poll time in seconds.
17089 @item @code{first-poll} (default @code{#f})
17090 Specifies how many seconds AutoSSH waits before the first connection
17091 test. After this first test, polling is resumed at the pace defined in
17092 @code{poll}. When set to @code{#f}, the first poll is not treated
17093 specially and will also use the connection poll specified in
17096 @item @code{gate-time} (default @code{30})
17097 Specifies how many seconds an SSH connection must be active before it is
17098 considered successful.
17100 @item @code{log-level} (default @code{1})
17101 The log level, corresponding to the levels used by syslog---so @code{0}
17102 is the most silent while @code{7} is the chattiest.
17104 @item @code{max-start} (default @code{#f})
17105 The maximum number of times SSH may be (re)started before AutoSSH exits.
17106 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
17108 @item @code{message} (default @code{""})
17109 The message to append to the echo message sent when testing connections.
17111 @item @code{port} (default @code{"0"})
17112 The ports used for monitoring the connection. When set to @code{"0"},
17113 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
17114 a positive integer, ports @var{n} and @var{n}+1 are used for
17115 monitoring the connection, such that port @var{n} is the base
17116 monitoring port and @code{n+1} is the echo port. When set to
17117 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
17118 integers, the ports @var{n} and @var{m} are used for monitoring the
17119 connection, such that port @var{n} is the base monitoring port and
17120 @var{m} is the echo port.
17122 @item @code{ssh-options} (default @code{'()})
17123 The list of command-line arguments to pass to @command{ssh} when it is
17124 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
17125 may cause undefined behaviour.
17131 @deffn {Scheme Variable} webssh-service-type
17132 This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
17133 program that runs a web SSH client. WebSSH can be run manually from the
17134 command-line by passing arguments to the binary @command{wssh} from the
17135 package @code{webssh}, but it can also be run as a Guix service. This
17136 latter use case is documented here.
17138 For example, to specify a service running WebSSH on loopback interface
17139 on port @code{8888} with reject policy with a list of allowed to
17140 connection hosts, and NGINX as a reverse-proxy to this service listening
17141 for HTTPS connection, add this call to the operating system's
17142 @code{services} field:
17145 (service webssh-service-type
17146 (webssh-configuration (address "127.0.0.1")
17149 (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
17150 "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
17152 (service nginx-service-type
17153 (nginx-configuration
17156 (nginx-server-configuration
17157 (inherit %webssh-configuration-nginx)
17158 (server-name '("webssh.example.com"))
17159 (listen '("443 ssl"))
17160 (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
17161 (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
17163 (cons (nginx-location-configuration
17164 (uri "/.well-known")
17165 (body '("root /var/www;")))
17166 (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
17170 @deftp {Data Type} webssh-configuration
17171 Data type representing the configuration for @code{webssh-service}.
17174 @item @code{package} (default: @var{webssh})
17175 @code{webssh} package to use.
17177 @item @code{user-name} (default: @var{"webssh"})
17178 User name or user ID that file transfers to and from that module should take
17181 @item @code{group-name} (default: @var{"webssh"})
17182 Group name or group ID that will be used when accessing the module.
17184 @item @code{address} (default: @var{#f})
17185 IP address on which @command{webssh} listens for incoming connections.
17187 @item @code{port} (default: @var{8888})
17188 TCP port on which @command{webssh} listens for incoming connections.
17190 @item @code{policy} (default: @var{#f})
17191 Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
17193 @item @code{known-hosts} (default: @var{'()})
17194 List of hosts which allowed for SSH connection from @command{webssh}.
17196 @item @code{log-file} (default: @file{"/var/log/webssh.log"})
17197 Name of the file where @command{webssh} writes its log file.
17199 @item @code{log-level} (default: @var{#f})
17205 @defvr {Scheme Variable} %facebook-host-aliases
17206 This variable contains a string for use in @file{/etc/hosts}
17207 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
17208 line contains a entry that maps a known server name of the Facebook
17209 on-line service---e.g., @code{www.facebook.com}---to the local
17210 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
17212 This variable is typically used in the @code{hosts-file} field of an
17213 @code{operating-system} declaration (@pxref{operating-system Reference,
17214 @file{/etc/hosts}}):
17217 (use-modules (gnu) (guix))
17220 (host-name "mymachine")
17223 ;; Create a /etc/hosts file with aliases for "localhost"
17224 ;; and "mymachine", as well as for Facebook servers.
17225 (plain-file "hosts"
17226 (string-append (local-host-aliases host-name)
17227 %facebook-host-aliases))))
17230 This mechanism can prevent programs running locally, such as Web
17231 browsers, from accessing Facebook.
17234 The @code{(gnu services avahi)} provides the following definition.
17236 @defvr {Scheme Variable} avahi-service-type
17237 This is the service that runs @command{avahi-daemon}, a system-wide
17238 mDNS/DNS-SD responder that allows for service discovery and
17239 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
17240 Its value must be an @code{avahi-configuration} record---see below.
17242 This service extends the name service cache daemon (nscd) so that it can
17243 resolve @code{.local} host names using
17244 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
17245 Service Switch}, for information on host name resolution.
17247 Additionally, add the @var{avahi} package to the system profile so that
17248 commands such as @command{avahi-browse} are directly usable.
17251 @deftp {Data Type} avahi-configuration
17252 Data type representation the configuration for Avahi.
17256 @item @code{host-name} (default: @code{#f})
17257 If different from @code{#f}, use that as the host name to
17258 publish for this machine; otherwise, use the machine's actual host name.
17260 @item @code{publish?} (default: @code{#t})
17261 When true, allow host names and services to be published (broadcast) over the
17264 @item @code{publish-workstation?} (default: @code{#t})
17265 When true, @command{avahi-daemon} publishes the machine's host name and IP
17266 address via mDNS on the local network. To view the host names published on
17267 your local network, you can run:
17270 avahi-browse _workstation._tcp
17273 @item @code{wide-area?} (default: @code{#f})
17274 When true, DNS-SD over unicast DNS is enabled.
17276 @item @code{ipv4?} (default: @code{#t})
17277 @itemx @code{ipv6?} (default: @code{#t})
17278 These fields determine whether to use IPv4/IPv6 sockets.
17280 @item @code{domains-to-browse} (default: @code{'()})
17281 This is a list of domains to browse.
17285 @deffn {Scheme Variable} openvswitch-service-type
17286 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
17287 service, whose value should be an @code{openvswitch-configuration}
17291 @deftp {Data Type} openvswitch-configuration
17292 Data type representing the configuration of Open vSwitch, a multilayer
17293 virtual switch which is designed to enable massive network automation
17294 through programmatic extension.
17297 @item @code{package} (default: @var{openvswitch})
17298 Package object of the Open vSwitch.
17303 @defvr {Scheme Variable} pagekite-service-type
17304 This is the service type for the @uref{https://pagekite.net, PageKite} service,
17305 a tunneling solution for making localhost servers publicly visible, even from
17306 behind restrictive firewalls or NAT without forwarded ports. The value for
17307 this service type is a @code{pagekite-configuration} record.
17309 Here's an example exposing the local HTTP and SSH daemons:
17312 (service pagekite-service-type
17313 (pagekite-configuration
17314 (kites '("http:@@kitename:localhost:80:@@kitesecret"
17315 "raw/22:@@kitename:localhost:22:@@kitesecret"))
17316 (extra-file "/etc/pagekite.rc")))
17320 @deftp {Data Type} pagekite-configuration
17321 Data type representing the configuration of PageKite.
17324 @item @code{package} (default: @var{pagekite})
17325 Package object of PageKite.
17327 @item @code{kitename} (default: @code{#f})
17328 PageKite name for authenticating to the frontend server.
17330 @item @code{kitesecret} (default: @code{#f})
17331 Shared secret for authenticating to the frontend server. You should probably
17332 put this inside @code{extra-file} instead.
17334 @item @code{frontend} (default: @code{#f})
17335 Connect to the named PageKite frontend server instead of the
17336 @uref{https://pagekite.net,,pagekite.net} service.
17338 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
17339 List of service kites to use. Exposes HTTP on port 80 by default. The format
17340 is @code{proto:kitename:host:port:secret}.
17342 @item @code{extra-file} (default: @code{#f})
17343 Extra configuration file to read, which you are expected to create manually.
17344 Use this to add additional options and manage shared secrets out-of-band.
17349 @defvr {Scheme Variable} yggdrasil-service-type
17350 The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
17351 Yggdrasil network}, an early-stage implementation of a fully end-to-end
17352 encrypted IPv6 network.
17355 Yggdrasil provides name-independent routing with cryptographically generated
17356 addresses. Static addressing means you can keep the same address as long as
17357 you want, even if you move to a new location, or generate a new address (by
17358 generating new keys) whenever you want.
17359 @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
17362 Pass it a value of @code{yggdrasil-configuration} to connect it to public
17363 peers and/or local peers.
17365 Here is an example using public peers and a static address. The static
17366 signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
17367 (the default value for @code{config-file}).
17370 ;; part of the operating-system declaration
17371 (service yggdrasil-service-type
17372 (yggdrasil-configuration
17373 (autoconf? #f) ;; use only the public peers
17376 ;; https://github.com/yggdrasil-network/public-peers
17377 '((peers . #("tcp://1.2.3.4:1337"))))
17378 ;; /etc/yggdrasil-private.conf is the default value for config-file
17382 # sample content for /etc/yggdrasil-private.conf
17384 # Your public encryption key. Your peers may ask you for this to put
17385 # into their AllowedEncryptionPublicKeys configuration.
17386 EncryptionPublicKey: 378dc5...
17388 # Your private encryption key. DO NOT share this with anyone!
17389 EncryptionPrivateKey: 0777...
17391 # Your public signing key. You should not ordinarily need to share
17392 # this with anyone.
17393 SigningPublicKey: e1664...
17395 # Your private signing key. DO NOT share this with anyone!
17396 SigningPrivateKey: 0589d...
17401 @deftp {Data Type} yggdrasil-configuration
17402 Data type representing the configuration of Yggdrasil.
17405 @item @code{package} (default: @code{yggdrasil})
17406 Package object of Yggdrasil.
17408 @item @code{json-config} (default: @code{'()})
17409 Contents of @file{/etc/yggdrasil.conf}. Will be merged with
17410 @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
17411 the Guix store, which is readable to all users. @strong{Do not store your
17412 private keys in it}. See the output of @code{yggdrasil -genconf} for a
17413 quick overview of valid keys and their default values.
17415 @item @code{autoconf?} (default: @code{#f})
17416 Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
17417 and peer with IPv6 neighbors.
17419 @item @code{log-level} (default: @code{'info})
17420 How much detail to include in logs. Use @code{'debug} for more detail.
17422 @item @code{log-to} (default: @code{'stdout})
17423 Where to send logs. By default, the service logs standard output to
17424 @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
17425 sends output to the running syslog service.
17427 @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
17428 What HJSON file to load sensitive data from. This is where private keys
17429 should be stored, which are necessary to specify if you don't want a
17430 randomized address after each restart. Use @code{#f} to disable. Options
17431 defined in this file take precedence over @code{json-config}. Use the output
17432 of @code{yggdrasil -genconf} as a starting point. To configure a static
17433 address, delete everything except these options:
17436 @item @code{EncryptionPublicKey}
17437 @item @code{EncryptionPrivateKey}
17438 @item @code{SigningPublicKey}
17439 @item @code{SigningPrivateKey}
17445 @deffn {Scheme Variable} keepalived-service-type
17446 This is the type for the @uref{https://www.keepalived.org/, Keepalived}
17447 routing software, @command{keepalived}. Its value must be an
17448 @code{keepalived-configuration} record as in this example for master
17452 (service keepalived-service-type
17453 (keepalived-configuration
17454 (config-file (local-file "keepalived-master.conf"))))
17457 where @file{keepalived-master.conf}:
17460 vrrp_instance my-group @{
17463 virtual_router_id 100
17465 unicast_peer @{ 10.0.0.2 @}
17466 virtual_ipaddress @{
17472 and for backup machine:
17475 (service keepalived-service-type
17476 (keepalived-configuration
17477 (config-file (local-file "keepalived-backup.conf"))))
17480 where @file{keepalived-backup.conf}:
17483 vrrp_instance my-group @{
17486 virtual_router_id 100
17488 unicast_peer @{ 10.0.0.3 @}
17489 virtual_ipaddress @{
17496 @node Unattended Upgrades
17497 @subsection Unattended Upgrades
17499 @cindex unattended upgrades
17500 @cindex upgrades, unattended
17501 Guix provides a service to perform @emph{unattended upgrades}:
17502 periodically, the system automatically reconfigures itself from the
17503 latest Guix. Guix System has several properties that make unattended
17508 upgrades are transactional (either the upgrade succeeds or it fails, but
17509 you cannot end up with an ``in-between'' system state);
17511 the upgrade log is kept---you can view it with @command{guix system
17512 list-generations}---and you can roll back to any previous generation,
17513 should the upgraded system fail to behave as intended;
17515 channel code is authenticated so you know you can only run genuine code
17516 (@pxref{Channels});
17518 @command{guix system reconfigure} prevents downgrades, which makes it
17519 immune to @dfn{downgrade attacks}.
17522 To set up unattended upgrades, add an instance of
17523 @code{unattended-upgrade-service-type} like the one below to the list of
17524 your operating system services:
17527 (service unattended-upgrade-service-type)
17530 The defaults above set up weekly upgrades: every Sunday at midnight.
17531 You do not need to provide the operating system configuration file: it
17532 uses @file{/run/current-system/configuration.scm}, which ensures it
17533 always uses your latest configuration---@pxref{provenance-service-type},
17534 for more information about this file.
17536 There are several things that can be configured, in particular the
17537 periodicity and services (daemons) to be restarted upon completion.
17538 When the upgrade is successful, the service takes care of deleting
17539 system generations older that some threshold, as per @command{guix
17540 system delete-generations}. See the reference below for details.
17542 To ensure that upgrades are actually happening, you can run
17543 @command{guix system describe}. To investigate upgrade failures, visit
17544 the unattended upgrade log file (see below).
17546 @defvr {Scheme Variable} unattended-upgrade-service-type
17547 This is the service type for unattended upgrades. It sets up an mcron
17548 job (@pxref{Scheduled Job Execution}) that runs @command{guix system
17549 reconfigure} from the latest version of the specified channels.
17551 Its value must be a @code{unattended-upgrade-configuration} record (see
17555 @deftp {Data Type} unattended-upgrade-configuration
17556 This data type represents the configuration of the unattended upgrade
17557 service. The following fields are available:
17560 @item @code{schedule} (default: @code{"30 01 * * 0"})
17561 This is the schedule of upgrades, expressed as a gexp containing an
17562 mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
17563 mcron, GNU@tie{}mcron}).
17565 @item @code{channels} (default: @code{#~%default-channels})
17566 This gexp specifies the channels to use for the upgrade
17567 (@pxref{Channels}). By default, the tip of the official @code{guix}
17570 @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
17571 This field specifies the operating system configuration file to use.
17572 The default is to reuse the config file of the current configuration.
17574 There are cases, though, where referring to
17575 @file{/run/current-system/configuration.scm} is not enough, for instance
17576 because that file refers to extra files (SSH public keys, extra
17577 configuration files, etc.) @i{via} @code{local-file} and similar
17578 constructs. For those cases, we recommend something along these lines:
17581 (unattended-upgrade-configuration
17582 (operating-system-file
17583 (file-append (local-file "." "config-dir" #:recursive? #t)
17587 The effect here is to import all of the current directory into the
17588 store, and to refer to @file{config.scm} within that directory.
17589 Therefore, uses of @code{local-file} within @file{config.scm} will work
17590 as expected. @xref{G-Expressions}, for information about
17591 @code{local-file} and @code{file-append}.
17593 @item @code{services-to-restart} (default: @code{'(mcron)})
17594 This field specifies the Shepherd services to restart when the upgrade
17597 Those services are restarted right away upon completion, as with
17598 @command{herd restart}, which ensures that the latest version is
17599 running---remember that by default @command{guix system reconfigure}
17600 only restarts services that are not currently running, which is
17601 conservative: it minimizes disruption but leaves outdated services
17604 Use @command{herd status} to find out candidates for restarting.
17605 @xref{Services}, for general information about services. Common
17606 services to restart would include @code{ntpd} and @code{ssh-daemon}.
17608 By default, the @code{mcron} service is restarted. This ensures that
17609 the latest version of the unattended upgrade job will be used next time.
17611 @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
17612 This is the expiration time in seconds for system generations. System
17613 generations older that this amount of time are deleted with
17614 @command{guix system delete-generations} when an upgrade completes.
17617 The unattended upgrade service does not run the garbage collector. You
17618 will probably want to set up your own mcron job to run @command{guix gc}
17622 @item @code{maximum-duration} (default: @code{3600})
17623 Maximum duration in seconds for the upgrade; past that time, the upgrade
17626 This is primarily useful to ensure the upgrade does not end up
17627 rebuilding or re-downloading ``the world''.
17629 @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
17630 File where unattended upgrades are logged.
17635 @subsection X Window
17638 @cindex X Window System
17639 @cindex login manager
17640 Support for the X Window graphical display system---specifically
17641 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
17642 there is no @code{xorg-service} procedure. Instead, the X server is
17643 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
17646 @cindex GNOME, login manager
17647 GDM of course allows users to log in into window managers and desktop
17648 environments other than GNOME; for those using GNOME, GDM is required for
17649 features such as automatic screen locking.
17651 @cindex window manager
17652 To use X11, you must install at least one @dfn{window manager}---for
17653 example the @code{windowmaker} or @code{openbox} packages---preferably
17654 by adding it to the @code{packages} field of your operating system
17655 definition (@pxref{operating-system Reference, system-wide packages}).
17657 @defvr {Scheme Variable} gdm-service-type
17658 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
17659 Desktop Manager} (GDM), a program that manages graphical display servers and
17660 handles graphical user logins. Its value must be a @code{gdm-configuration}
17663 @cindex session types (X11)
17664 @cindex X11 session types
17665 GDM looks for @dfn{session types} described by the @file{.desktop} files in
17666 @file{/run/current-system/profile/share/xsessions} and allows users to choose
17667 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
17668 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
17669 set of packages automatically makes them available at the log-in screen.
17671 In addition, @file{~/.xsession} files are honored. When available,
17672 @file{~/.xsession} must be an executable that starts a window manager
17673 and/or other X clients.
17676 @deftp {Data Type} gdm-configuration
17678 @item @code{auto-login?} (default: @code{#f})
17679 @itemx @code{default-user} (default: @code{#f})
17680 When @code{auto-login?} is false, GDM presents a log-in screen.
17682 When @code{auto-login?} is true, GDM logs in directly as
17683 @code{default-user}.
17685 @item @code{debug?} (default: @code{#f})
17686 When true, GDM writes debug messages to its log.
17688 @item @code{gnome-shell-assets} (default: ...)
17689 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
17691 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
17692 Configuration of the Xorg graphical server.
17694 @item @code{xsession} (default: @code{(xinitrc)})
17695 Script to run before starting a X session.
17697 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
17698 File name of the @code{dbus-daemon} executable.
17700 @item @code{gdm} (default: @code{gdm})
17701 The GDM package to use.
17705 @defvr {Scheme Variable} slim-service-type
17706 This is the type for the SLiM graphical login manager for X11.
17708 Like GDM, SLiM looks for session types described by @file{.desktop} files and
17709 allows users to choose a session from the log-in screen using @kbd{F1}. It
17710 also honors @file{~/.xsession} files.
17712 Unlike GDM, SLiM does not spawn the user session on a different VT after
17713 logging in, which means that you can only start one graphical session. If you
17714 want to be able to run multiple graphical sessions at the same time you have
17715 to add multiple SLiM services to your system services. The following example
17716 shows how to replace the default GDM service with two SLiM services on tty7
17720 (use-modules (gnu services)
17721 (gnu services desktop)
17722 (gnu services xorg)
17723 (srfi srfi-1)) ;for 'remove'
17727 (services (cons* (service slim-service-type (slim-configuration
17730 (service slim-service-type (slim-configuration
17733 (remove (lambda (service)
17734 (eq? (service-kind service) gdm-service-type))
17735 %desktop-services))))
17740 @deftp {Data Type} slim-configuration
17741 Data type representing the configuration of @code{slim-service-type}.
17744 @item @code{allow-empty-passwords?} (default: @code{#t})
17745 Whether to allow logins with empty passwords.
17747 @item @code{auto-login?} (default: @code{#f})
17748 @itemx @code{default-user} (default: @code{""})
17749 When @code{auto-login?} is false, SLiM presents a log-in screen.
17751 When @code{auto-login?} is true, SLiM logs in directly as
17752 @code{default-user}.
17754 @item @code{theme} (default: @code{%default-slim-theme})
17755 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
17756 The graphical theme to use and its name.
17758 @item @code{auto-login-session} (default: @code{#f})
17759 If true, this must be the name of the executable to start as the default
17760 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
17762 If false, a session described by one of the available @file{.desktop}
17763 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
17767 You must install at least one window manager in the system profile or in
17768 your user profile. Failing to do that, if @code{auto-login-session} is
17769 false, you will be unable to log in.
17772 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
17773 Configuration of the Xorg graphical server.
17775 @item @code{display} (default @code{":0"})
17776 The display on which to start the Xorg graphical server.
17778 @item @code{vt} (default @code{"vt7"})
17779 The VT on which to start the Xorg graphical server.
17781 @item @code{xauth} (default: @code{xauth})
17782 The XAuth package to use.
17784 @item @code{shepherd} (default: @code{shepherd})
17785 The Shepherd package used when invoking @command{halt} and
17788 @item @code{sessreg} (default: @code{sessreg})
17789 The sessreg package used in order to register the session.
17791 @item @code{slim} (default: @code{slim})
17792 The SLiM package to use.
17796 @defvr {Scheme Variable} %default-theme
17797 @defvrx {Scheme Variable} %default-theme-name
17798 The default SLiM theme and its name.
17802 @deftp {Data Type} sddm-configuration
17803 This is the data type representing the SDDM service configuration.
17806 @item @code{display-server} (default: "x11")
17807 Select display server to use for the greeter. Valid values are
17808 @samp{"x11"} or @samp{"wayland"}.
17810 @item @code{numlock} (default: "on")
17811 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
17813 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
17814 Command to run when halting.
17816 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
17817 Command to run when rebooting.
17819 @item @code{theme} (default "maldives")
17820 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
17821 @samp{"maldives"} or @samp{"maya"}.
17823 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
17824 Directory to look for themes.
17826 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
17827 Directory to look for faces.
17829 @item @code{default-path} (default "/run/current-system/profile/bin")
17830 Default PATH to use.
17832 @item @code{minimum-uid} (default: 1000)
17833 Minimum UID displayed in SDDM and allowed for log-in.
17835 @item @code{maximum-uid} (default: 2000)
17836 Maximum UID to display in SDDM.
17838 @item @code{remember-last-user?} (default #t)
17839 Remember last user.
17841 @item @code{remember-last-session?} (default #t)
17842 Remember last session.
17844 @item @code{hide-users} (default "")
17845 Usernames to hide from SDDM greeter.
17847 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
17848 Users with shells listed will be hidden from the SDDM greeter.
17850 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
17851 Script to run before starting a wayland session.
17853 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
17854 Directory to look for desktop files starting wayland sessions.
17856 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
17857 Configuration of the Xorg graphical server.
17859 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
17862 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
17865 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
17866 Script to run after starting xorg-server.
17868 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
17869 Script to run before stopping xorg-server.
17871 @item @code{xsession-command} (default: @code{xinitrc})
17872 Script to run before starting a X session.
17874 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
17875 Directory to look for desktop files starting X sessions.
17877 @item @code{minimum-vt} (default: 7)
17880 @item @code{auto-login-user} (default "")
17881 User to use for auto-login.
17883 @item @code{auto-login-session} (default "")
17884 Desktop file to use for auto-login.
17886 @item @code{relogin?} (default #f)
17887 Relogin after logout.
17892 @cindex login manager
17894 @defvr {Scheme Variable} sddm-service-type
17895 This is the type of the service to run the
17896 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
17897 must be a @code{sddm-configuration} record (see below).
17899 Here's an example use:
17902 (service sddm-service-type
17903 (sddm-configuration
17904 (auto-login-user "alice")
17905 (auto-login-session "xfce.desktop")))
17909 @deftp {Data Type} sddm-configuration
17910 This data type represents the configuration of the SDDM login manager.
17911 The available fields are:
17914 @item @code{sddm} (default: @code{sddm})
17915 The SDDM package to use.
17917 @item @code{display-server} (default: @code{"x11"})
17918 This must be either @code{"x11"} or @code{"wayland"}.
17920 @c FIXME: Add more fields.
17922 @item @code{auto-login-user} (default: @code{""})
17923 If non-empty, this is the user account under which to log in
17926 @item @code{auto-login-session} (default: @code{""})
17927 If non-empty, this is the @file{.desktop} file name to use as the
17928 auto-login session.
17932 @cindex Xorg, configuration
17933 @deftp {Data Type} xorg-configuration
17934 This data type represents the configuration of the Xorg graphical display
17935 server. Note that there is no Xorg service; instead, the X server is started
17936 by a ``display manager'' such as GDM, SDDM, and SLiM@. Thus, the configuration
17937 of these display managers aggregates an @code{xorg-configuration} record.
17940 @item @code{modules} (default: @code{%default-xorg-modules})
17941 This is a list of @dfn{module packages} loaded by the Xorg
17942 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
17944 @item @code{fonts} (default: @code{%default-xorg-fonts})
17945 This is a list of font directories to add to the server's @dfn{font path}.
17947 @item @code{drivers} (default: @code{'()})
17948 This must be either the empty list, in which case Xorg chooses a graphics
17949 driver automatically, or a list of driver names that will be tried in this
17950 order---e.g., @code{("modesetting" "vesa")}.
17952 @item @code{resolutions} (default: @code{'()})
17953 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
17954 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
17957 @cindex keyboard layout, for Xorg
17958 @cindex keymap, for Xorg
17959 @item @code{keyboard-layout} (default: @code{#f})
17960 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
17961 English (``qwerty'') for a 105-key PC keyboard.
17963 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
17964 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
17965 information on how to specify the keyboard layout.
17967 @item @code{extra-config} (default: @code{'()})
17968 This is a list of strings or objects appended to the configuration file. It
17969 is used to pass extra text to be added verbatim to the configuration file.
17971 @item @code{server} (default: @code{xorg-server})
17972 This is the package providing the Xorg server.
17974 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
17975 This is the list of command-line arguments to pass to the X server. The
17976 default is @code{-nolisten tcp}.
17980 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
17981 [@var{login-manager-service-type}]
17982 Tell the log-in manager (of type @var{login-manager-service-type}) to use
17983 @var{config}, an @code{<xorg-configuration>} record.
17985 Since the Xorg configuration is embedded in the log-in manager's
17986 configuration---e.g., @code{gdm-configuration}---this procedure provides a
17987 shorthand to set the Xorg configuration.
17990 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
17991 Return a @code{startx} script in which the modules, fonts, etc. specified
17992 in @var{config}, are available. The result should be used in place of
17995 Usually the X server is started by a login manager.
17999 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
18000 Add @var{package}, a package for a screen locker or screen saver whose
18001 command is @var{program}, to the set of setuid programs and add a PAM entry
18002 for it. For example:
18005 (screen-locker-service xlockmore "xlock")
18008 makes the good ol' XlockMore usable.
18012 @node Printing Services
18013 @subsection Printing Services
18015 @cindex printer support with CUPS
18016 The @code{(gnu services cups)} module provides a Guix service definition
18017 for the CUPS printing service. To add printer support to a Guix
18018 system, add a @code{cups-service} to the operating system definition:
18020 @deffn {Scheme Variable} cups-service-type
18021 The service type for the CUPS print server. Its value should be a valid
18022 CUPS configuration (see below). To use the default settings, simply
18025 (service cups-service-type)
18029 The CUPS configuration controls the basic things about your CUPS
18030 installation: what interfaces it listens on, what to do if a print job
18031 fails, how much logging to do, and so on. To actually add a printer,
18032 you have to visit the @url{http://localhost:631} URL, or use a tool such
18033 as GNOME's printer configuration services. By default, configuring a
18034 CUPS service will generate a self-signed certificate if needed, for
18035 secure connections to the print server.
18037 Suppose you want to enable the Web interface of CUPS and also add
18038 support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
18039 package and for HP printers @i{via} the @code{hplip-minimal} package.
18040 You can do that directly, like this (you need to use the
18041 @code{(gnu packages cups)} module):
18044 (service cups-service-type
18045 (cups-configuration
18046 (web-interface? #t)
18048 (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
18051 Note: If you wish to use the Qt5 based GUI which comes with the hplip
18052 package then it is suggested that you install the @code{hplip} package,
18053 either in your OS configuration file or as your user.
18055 The available configuration parameters follow. Each parameter
18056 definition is preceded by its type; for example, @samp{string-list foo}
18057 indicates that the @code{foo} parameter should be specified as a list of
18058 strings. There is also a way to specify the configuration as a string,
18059 if you have an old @code{cupsd.conf} file that you want to port over
18060 from some other system; see the end for more details.
18062 @c The following documentation was initially generated by
18063 @c (generate-documentation) in (gnu services cups). Manually maintained
18064 @c documentation is better, so we shouldn't hesitate to edit below as
18065 @c needed. However if the change you want to make to this documentation
18066 @c can be done in an automated way, it's probably easier to change
18067 @c (generate-documentation) than to make it below and have to deal with
18068 @c the churn as CUPS updates.
18071 Available @code{cups-configuration} fields are:
18073 @deftypevr {@code{cups-configuration} parameter} package cups
18077 @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list brlaser cups-filters epson-inkjet-printer-escpr foomatic-filters hplip-minimal splix)})
18078 Drivers and other extensions to the CUPS package.
18081 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
18082 Configuration of where to write logs, what directories to use for print
18083 spools, and related privileged configuration parameters.
18085 Available @code{files-configuration} fields are:
18087 @deftypevr {@code{files-configuration} parameter} log-location access-log
18088 Defines the access log filename. Specifying a blank filename disables
18089 access log generation. The value @code{stderr} causes log entries to be
18090 sent to the standard error file when the scheduler is running in the
18091 foreground, or to the system log daemon when run in the background. The
18092 value @code{syslog} causes log entries to be sent to the system log
18093 daemon. The server name may be included in filenames using the string
18094 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
18096 Defaults to @samp{"/var/log/cups/access_log"}.
18099 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
18100 Where CUPS should cache data.
18102 Defaults to @samp{"/var/cache/cups"}.
18105 @deftypevr {@code{files-configuration} parameter} string config-file-perm
18106 Specifies the permissions for all configuration files that the scheduler
18109 Note that the permissions for the printers.conf file are currently
18110 masked to only allow access from the scheduler user (typically root).
18111 This is done because printer device URIs sometimes contain sensitive
18112 authentication information that should not be generally known on the
18113 system. There is no way to disable this security feature.
18115 Defaults to @samp{"0640"}.
18118 @deftypevr {@code{files-configuration} parameter} log-location error-log
18119 Defines the error log filename. Specifying a blank filename disables
18120 error log generation. The value @code{stderr} causes log entries to be
18121 sent to the standard error file when the scheduler is running in the
18122 foreground, or to the system log daemon when run in the background. The
18123 value @code{syslog} causes log entries to be sent to the system log
18124 daemon. The server name may be included in filenames using the string
18125 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
18127 Defaults to @samp{"/var/log/cups/error_log"}.
18130 @deftypevr {@code{files-configuration} parameter} string fatal-errors
18131 Specifies which errors are fatal, causing the scheduler to exit. The
18136 No errors are fatal.
18139 All of the errors below are fatal.
18142 Browsing initialization errors are fatal, for example failed connections
18143 to the DNS-SD daemon.
18146 Configuration file syntax errors are fatal.
18149 Listen or Port errors are fatal, except for IPv6 failures on the
18150 loopback or @code{any} addresses.
18153 Log file creation or write errors are fatal.
18156 Bad startup file permissions are fatal, for example shared TLS
18157 certificate and key files with world-read permissions.
18160 Defaults to @samp{"all -browse"}.
18163 @deftypevr {@code{files-configuration} parameter} boolean file-device?
18164 Specifies whether the file pseudo-device can be used for new printer
18165 queues. The URI @uref{file:///dev/null} is always allowed.
18167 Defaults to @samp{#f}.
18170 @deftypevr {@code{files-configuration} parameter} string group
18171 Specifies the group name or ID that will be used when executing external
18174 Defaults to @samp{"lp"}.
18177 @deftypevr {@code{files-configuration} parameter} string log-file-perm
18178 Specifies the permissions for all log files that the scheduler writes.
18180 Defaults to @samp{"0644"}.
18183 @deftypevr {@code{files-configuration} parameter} log-location page-log
18184 Defines the page log filename. Specifying a blank filename disables
18185 page log generation. The value @code{stderr} causes log entries to be
18186 sent to the standard error file when the scheduler is running in the
18187 foreground, or to the system log daemon when run in the background. The
18188 value @code{syslog} causes log entries to be sent to the system log
18189 daemon. The server name may be included in filenames using the string
18190 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
18192 Defaults to @samp{"/var/log/cups/page_log"}.
18195 @deftypevr {@code{files-configuration} parameter} string remote-root
18196 Specifies the username that is associated with unauthenticated accesses
18197 by clients claiming to be the root user. The default is @code{remroot}.
18199 Defaults to @samp{"remroot"}.
18202 @deftypevr {@code{files-configuration} parameter} file-name request-root
18203 Specifies the directory that contains print jobs and other HTTP request
18206 Defaults to @samp{"/var/spool/cups"}.
18209 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
18210 Specifies the level of security sandboxing that is applied to print
18211 filters, backends, and other child processes of the scheduler; either
18212 @code{relaxed} or @code{strict}. This directive is currently only
18213 used/supported on macOS.
18215 Defaults to @samp{strict}.
18218 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
18219 Specifies the location of TLS certificates and private keys. CUPS will
18220 look for public and private keys in this directory: @file{.crt} files
18221 for PEM-encoded certificates and corresponding @file{.key} files for
18222 PEM-encoded private keys.
18224 Defaults to @samp{"/etc/cups/ssl"}.
18227 @deftypevr {@code{files-configuration} parameter} file-name server-root
18228 Specifies the directory containing the server configuration files.
18230 Defaults to @samp{"/etc/cups"}.
18233 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
18234 Specifies whether the scheduler calls fsync(2) after writing
18235 configuration or state files.
18237 Defaults to @samp{#f}.
18240 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
18241 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
18244 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
18245 Specifies the directory where temporary files are stored.
18247 Defaults to @samp{"/var/spool/cups/tmp"}.
18250 @deftypevr {@code{files-configuration} parameter} string user
18251 Specifies the user name or ID that is used when running external
18254 Defaults to @samp{"lp"}.
18257 @deftypevr {@code{files-configuration} parameter} string set-env
18258 Set the specified environment variable to be passed to child processes.
18260 Defaults to @samp{"variable value"}.
18264 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
18265 Specifies the logging level for the AccessLog file. The @code{config}
18266 level logs when printers and classes are added, deleted, or modified and
18267 when configuration files are accessed or updated. The @code{actions}
18268 level logs when print jobs are submitted, held, released, modified, or
18269 canceled, and any of the conditions for @code{config}. The @code{all}
18270 level logs all requests.
18272 Defaults to @samp{actions}.
18275 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
18276 Specifies whether to purge job history data automatically when it is no
18277 longer required for quotas.
18279 Defaults to @samp{#f}.
18282 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
18283 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
18284 For example, @samp{"_cups" "_print"} will tell network clients that both
18285 CUPS sharing and IPP Everywhere are supported.
18287 Defaults to @samp{"_cups"}.
18290 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
18291 Specifies which protocols to use for local printer sharing.
18293 Defaults to @samp{dnssd}.
18296 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
18297 Specifies whether the CUPS web interface is advertised.
18299 Defaults to @samp{#f}.
18302 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
18303 Specifies whether shared printers are advertised.
18305 Defaults to @samp{#f}.
18308 @deftypevr {@code{cups-configuration} parameter} string classification
18309 Specifies the security classification of the server. Any valid banner
18310 name can be used, including @samp{"classified"}, @samp{"confidential"},
18311 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
18312 banner can be omitted to disable secure printing functions.
18314 Defaults to @samp{""}.
18317 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
18318 Specifies whether users may override the classification (cover page) of
18319 individual print jobs using the @code{job-sheets} option.
18321 Defaults to @samp{#f}.
18324 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
18325 Specifies the default type of authentication to use.
18327 Defaults to @samp{Basic}.
18330 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
18331 Specifies whether encryption will be used for authenticated requests.
18333 Defaults to @samp{Required}.
18336 @deftypevr {@code{cups-configuration} parameter} string default-language
18337 Specifies the default language to use for text and web content.
18339 Defaults to @samp{"en"}.
18342 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
18343 Specifies the default paper size for new print queues. @samp{"Auto"}
18344 uses a locale-specific default, while @samp{"None"} specifies there is
18345 no default paper size. Specific size names are typically
18346 @samp{"Letter"} or @samp{"A4"}.
18348 Defaults to @samp{"Auto"}.
18351 @deftypevr {@code{cups-configuration} parameter} string default-policy
18352 Specifies the default access policy to use.
18354 Defaults to @samp{"default"}.
18357 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
18358 Specifies whether local printers are shared by default.
18360 Defaults to @samp{#t}.
18363 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
18364 Specifies the delay for updating of configuration and state files, in
18365 seconds. A value of 0 causes the update to happen as soon as possible,
18366 typically within a few milliseconds.
18368 Defaults to @samp{30}.
18371 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
18372 Specifies what to do when an error occurs. Possible values are
18373 @code{abort-job}, which will discard the failed print job;
18374 @code{retry-job}, which will retry the job at a later time;
18375 @code{retry-current-job}, which retries the failed job immediately; and
18376 @code{stop-printer}, which stops the printer.
18378 Defaults to @samp{stop-printer}.
18381 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
18382 Specifies the maximum cost of filters that are run concurrently, which
18383 can be used to minimize disk, memory, and CPU resource problems. A
18384 limit of 0 disables filter limiting. An average print to a
18385 non-PostScript printer needs a filter limit of about 200. A PostScript
18386 printer needs about half that (100). Setting the limit below these
18387 thresholds will effectively limit the scheduler to printing a single job
18390 Defaults to @samp{0}.
18393 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
18394 Specifies the scheduling priority of filters that are run to print a
18395 job. The nice value ranges from 0, the highest priority, to 19, the
18398 Defaults to @samp{0}.
18401 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
18402 Specifies whether to do reverse lookups on connecting clients. The
18403 @code{double} setting causes @code{cupsd} to verify that the hostname
18404 resolved from the address matches one of the addresses returned for that
18405 hostname. Double lookups also prevent clients with unregistered
18406 addresses from connecting to your server. Only set this option to
18407 @code{#t} or @code{double} if absolutely required.
18409 Defaults to @samp{#f}.
18412 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
18413 Specifies the number of seconds to wait before killing the filters and
18414 backend associated with a canceled or held job.
18416 Defaults to @samp{30}.
18419 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
18420 Specifies the interval between retries of jobs in seconds. This is
18421 typically used for fax queues but can also be used with normal print
18422 queues whose error policy is @code{retry-job} or
18423 @code{retry-current-job}.
18425 Defaults to @samp{30}.
18428 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
18429 Specifies the number of retries that are done for jobs. This is
18430 typically used for fax queues but can also be used with normal print
18431 queues whose error policy is @code{retry-job} or
18432 @code{retry-current-job}.
18434 Defaults to @samp{5}.
18437 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
18438 Specifies whether to support HTTP keep-alive connections.
18440 Defaults to @samp{#t}.
18443 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
18444 Specifies how long an idle client connection remains open, in seconds.
18446 Defaults to @samp{30}.
18449 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
18450 Specifies the maximum size of print files, IPP requests, and HTML form
18451 data. A limit of 0 disables the limit check.
18453 Defaults to @samp{0}.
18456 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
18457 Listens on the specified interfaces for connections. Valid values are
18458 of the form @var{address}:@var{port}, where @var{address} is either an
18459 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
18460 indicate all addresses. Values can also be file names of local UNIX
18461 domain sockets. The Listen directive is similar to the Port directive
18462 but allows you to restrict access to specific interfaces or networks.
18465 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
18466 Specifies the number of pending connections that will be allowed. This
18467 normally only affects very busy servers that have reached the MaxClients
18468 limit, but can also be triggered by large numbers of simultaneous
18469 connections. When the limit is reached, the operating system will
18470 refuse additional connections until the scheduler can accept the pending
18473 Defaults to @samp{128}.
18476 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
18477 Specifies a set of additional access controls.
18479 Available @code{location-access-controls} fields are:
18481 @deftypevr {@code{location-access-controls} parameter} file-name path
18482 Specifies the URI path to which the access control applies.
18485 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
18486 Access controls for all access to this path, in the same format as the
18487 @code{access-controls} of @code{operation-access-control}.
18489 Defaults to @samp{()}.
18492 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
18493 Access controls for method-specific access to this path.
18495 Defaults to @samp{()}.
18497 Available @code{method-access-controls} fields are:
18499 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
18500 If @code{#t}, apply access controls to all methods except the listed
18501 methods. Otherwise apply to only the listed methods.
18503 Defaults to @samp{#f}.
18506 @deftypevr {@code{method-access-controls} parameter} method-list methods
18507 Methods to which this access control applies.
18509 Defaults to @samp{()}.
18512 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
18513 Access control directives, as a list of strings. Each string should be
18514 one directive, such as @samp{"Order allow,deny"}.
18516 Defaults to @samp{()}.
18521 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
18522 Specifies the number of debugging messages that are retained for logging
18523 if an error occurs in a print job. Debug messages are logged regardless
18524 of the LogLevel setting.
18526 Defaults to @samp{100}.
18529 @deftypevr {@code{cups-configuration} parameter} log-level log-level
18530 Specifies the level of logging for the ErrorLog file. The value
18531 @code{none} stops all logging while @code{debug2} logs everything.
18533 Defaults to @samp{info}.
18536 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
18537 Specifies the format of the date and time in the log files. The value
18538 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
18540 Defaults to @samp{standard}.
18543 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
18544 Specifies the maximum number of simultaneous clients that are allowed by
18547 Defaults to @samp{100}.
18550 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
18551 Specifies the maximum number of simultaneous clients that are allowed
18552 from a single address.
18554 Defaults to @samp{100}.
18557 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
18558 Specifies the maximum number of copies that a user can print of each
18561 Defaults to @samp{9999}.
18564 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
18565 Specifies the maximum time a job may remain in the @code{indefinite}
18566 hold state before it is canceled. A value of 0 disables cancellation of
18569 Defaults to @samp{0}.
18572 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
18573 Specifies the maximum number of simultaneous jobs that are allowed. Set
18574 to 0 to allow an unlimited number of jobs.
18576 Defaults to @samp{500}.
18579 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
18580 Specifies the maximum number of simultaneous jobs that are allowed per
18581 printer. A value of 0 allows up to MaxJobs jobs per printer.
18583 Defaults to @samp{0}.
18586 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
18587 Specifies the maximum number of simultaneous jobs that are allowed per
18588 user. A value of 0 allows up to MaxJobs jobs per user.
18590 Defaults to @samp{0}.
18593 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
18594 Specifies the maximum time a job may take to print before it is
18595 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
18597 Defaults to @samp{10800}.
18600 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
18601 Specifies the maximum size of the log files before they are rotated, in
18602 bytes. The value 0 disables log rotation.
18604 Defaults to @samp{1048576}.
18607 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
18608 Specifies the maximum amount of time to allow between files in a
18609 multiple file print job, in seconds.
18611 Defaults to @samp{300}.
18614 @deftypevr {@code{cups-configuration} parameter} string page-log-format
18615 Specifies the format of PageLog lines. Sequences beginning with percent
18616 (@samp{%}) characters are replaced with the corresponding information,
18617 while all other characters are copied literally. The following percent
18618 sequences are recognized:
18622 insert a single percent character
18625 insert the value of the specified IPP attribute
18628 insert the number of copies for the current page
18631 insert the current page number
18634 insert the current date and time in common log format
18640 insert the printer name
18643 insert the username
18646 A value of the empty string disables page logging. The string @code{%p
18647 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
18648 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
18651 Defaults to @samp{""}.
18654 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
18655 Passes the specified environment variable(s) to child processes; a list
18658 Defaults to @samp{()}.
18661 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
18662 Specifies named access control policies.
18664 Available @code{policy-configuration} fields are:
18666 @deftypevr {@code{policy-configuration} parameter} string name
18667 Name of the policy.
18670 @deftypevr {@code{policy-configuration} parameter} string job-private-access
18671 Specifies an access list for a job's private values. @code{@@ACL} maps
18672 to the printer's requesting-user-name-allowed or
18673 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
18674 owner. @code{@@SYSTEM} maps to the groups listed for the
18675 @code{system-group} field of the @code{files-config} configuration,
18676 which is reified into the @code{cups-files.conf(5)} file. Other
18677 possible elements of the access list include specific user names, and
18678 @code{@@@var{group}} to indicate members of a specific group. The
18679 access list may also be simply @code{all} or @code{default}.
18681 Defaults to @samp{"@@OWNER @@SYSTEM"}.
18684 @deftypevr {@code{policy-configuration} parameter} string job-private-values
18685 Specifies the list of job values to make private, or @code{all},
18686 @code{default}, or @code{none}.
18688 Defaults to @samp{"job-name job-originating-host-name
18689 job-originating-user-name phone"}.
18692 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
18693 Specifies an access list for a subscription's private values.
18694 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
18695 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
18696 owner. @code{@@SYSTEM} maps to the groups listed for the
18697 @code{system-group} field of the @code{files-config} configuration,
18698 which is reified into the @code{cups-files.conf(5)} file. Other
18699 possible elements of the access list include specific user names, and
18700 @code{@@@var{group}} to indicate members of a specific group. The
18701 access list may also be simply @code{all} or @code{default}.
18703 Defaults to @samp{"@@OWNER @@SYSTEM"}.
18706 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
18707 Specifies the list of job values to make private, or @code{all},
18708 @code{default}, or @code{none}.
18710 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
18711 notify-subscriber-user-name notify-user-data"}.
18714 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
18715 Access control by IPP operation.
18717 Defaults to @samp{()}.
18721 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
18722 Specifies whether job files (documents) are preserved after a job is
18723 printed. If a numeric value is specified, job files are preserved for
18724 the indicated number of seconds after printing. Otherwise a boolean
18725 value applies indefinitely.
18727 Defaults to @samp{86400}.
18730 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
18731 Specifies whether the job history is preserved after a job is printed.
18732 If a numeric value is specified, the job history is preserved for the
18733 indicated number of seconds after printing. If @code{#t}, the job
18734 history is preserved until the MaxJobs limit is reached.
18736 Defaults to @samp{#t}.
18739 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
18740 Specifies the amount of time to wait for job completion before
18741 restarting the scheduler.
18743 Defaults to @samp{30}.
18746 @deftypevr {@code{cups-configuration} parameter} string rip-cache
18747 Specifies the maximum amount of memory to use when converting documents
18748 into bitmaps for a printer.
18750 Defaults to @samp{"128m"}.
18753 @deftypevr {@code{cups-configuration} parameter} string server-admin
18754 Specifies the email address of the server administrator.
18756 Defaults to @samp{"root@@localhost.localdomain"}.
18759 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
18760 The ServerAlias directive is used for HTTP Host header validation when
18761 clients connect to the scheduler from external interfaces. Using the
18762 special name @code{*} can expose your system to known browser-based DNS
18763 rebinding attacks, even when accessing sites through a firewall. If the
18764 auto-discovery of alternate names does not work, we recommend listing
18765 each alternate name with a ServerAlias directive instead of using
18768 Defaults to @samp{*}.
18771 @deftypevr {@code{cups-configuration} parameter} string server-name
18772 Specifies the fully-qualified host name of the server.
18774 Defaults to @samp{"localhost"}.
18777 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
18778 Specifies what information is included in the Server header of HTTP
18779 responses. @code{None} disables the Server header. @code{ProductOnly}
18780 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
18781 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
18782 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
18783 the output of the @code{uname} command. @code{Full} reports @code{CUPS
18784 2.0.0 (@var{uname}) IPP/2.0}.
18786 Defaults to @samp{Minimal}.
18789 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
18790 Listens on the specified interfaces for encrypted connections. Valid
18791 values are of the form @var{address}:@var{port}, where @var{address} is
18792 either an IPv6 address enclosed in brackets, an IPv4 address, or
18793 @code{*} to indicate all addresses.
18795 Defaults to @samp{()}.
18798 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
18799 Sets encryption options. By default, CUPS only supports encryption
18800 using TLS v1.0 or higher using known secure cipher suites. Security is
18801 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
18802 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
18803 suites, which are required for some older clients. The @code{AllowSSL3} option
18804 enables SSL v3.0, which is required for some older clients that do not support
18805 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
18806 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
18807 protocol version to TLS v1.1.
18809 Defaults to @samp{()}.
18812 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
18813 Specifies whether the scheduler requires clients to strictly adhere to
18814 the IPP specifications.
18816 Defaults to @samp{#f}.
18819 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
18820 Specifies the HTTP request timeout, in seconds.
18822 Defaults to @samp{300}.
18826 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
18827 Specifies whether the web interface is enabled.
18829 Defaults to @samp{#f}.
18832 At this point you're probably thinking ``oh dear, Guix manual, I like
18833 you but you can stop already with the configuration options''. Indeed.
18834 However, one more point: it could be that you have an existing
18835 @code{cupsd.conf} that you want to use. In that case, you can pass an
18836 @code{opaque-cups-configuration} as the configuration of a
18837 @code{cups-service-type}.
18839 Available @code{opaque-cups-configuration} fields are:
18841 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
18845 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
18846 The contents of the @code{cupsd.conf}, as a string.
18849 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
18850 The contents of the @code{cups-files.conf} file, as a string.
18853 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
18854 strings of the same name, you could instantiate a CUPS service like
18858 (service cups-service-type
18859 (opaque-cups-configuration
18860 (cupsd.conf cupsd.conf)
18861 (cups-files.conf cups-files.conf)))
18865 @node Desktop Services
18866 @subsection Desktop Services
18868 The @code{(gnu services desktop)} module provides services that are
18869 usually useful in the context of a ``desktop'' setup---that is, on a
18870 machine running a graphical display server, possibly with graphical user
18871 interfaces, etc. It also defines services that provide specific desktop
18872 environments like GNOME, Xfce or MATE.
18874 To simplify things, the module defines a variable containing the set of
18875 services that users typically expect on a machine with a graphical
18876 environment and networking:
18878 @defvr {Scheme Variable} %desktop-services
18879 This is a list of services that builds upon @code{%base-services} and
18880 adds or adjusts services for a typical ``desktop'' setup.
18882 In particular, it adds a graphical login manager (@pxref{X Window,
18883 @code{gdm-service-type}}), screen lockers, a network management tool
18884 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
18885 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
18886 energy and color management services, the @code{elogind} login and seat
18887 manager, the Polkit privilege service, the GeoClue location service, the
18888 AccountsService daemon that allows authorized users change system passwords,
18889 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
18890 name service switch service configured to be able to use @code{nss-mdns}
18891 (@pxref{Name Service Switch, mDNS}).
18894 The @code{%desktop-services} variable can be used as the @code{services}
18895 field of an @code{operating-system} declaration (@pxref{operating-system
18896 Reference, @code{services}}).
18898 Additionally, the @code{gnome-desktop-service-type},
18899 @code{xfce-desktop-service}, @code{mate-desktop-service-type},
18900 @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
18901 procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
18902 ``add GNOME'' means that system-level services like the backlight adjustment
18903 helpers and the power management utilities are added to the system, extending
18904 @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
18905 elevated privileges on a limited number of special-purpose system interfaces.
18906 Additionally, adding a service made by @code{gnome-desktop-service-type} adds
18907 the GNOME metapackage to the system profile. Likewise, adding the Xfce
18908 service not only adds the @code{xfce} metapackage to the system profile, but
18909 it also gives the Thunar file manager the ability to open a ``root-mode'' file
18910 management window, if the user authenticates using the administrator's
18911 password via the standard polkit graphical interface. To ``add MATE'' means
18912 that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
18913 to operate with elevated privileges on a limited number of special-purpose
18914 system interfaces. Additionally, adding a service of type
18915 @code{mate-desktop-service-type} adds the MATE metapackage to the system
18916 profile. ``Adding Enlightenment'' means that @code{dbus} is extended
18917 appropriately, and several of Enlightenment's binaries are set as setuid,
18918 allowing Enlightenment's screen locker and other functionality to work as
18921 The desktop environments in Guix use the Xorg display server by
18922 default. If you'd like to use the newer display server protocol
18923 called Wayland, you need to use the @code{sddm-service} instead of
18924 GDM as the graphical login manager. You should then
18925 select the ``GNOME (Wayland)'' session in SDDM@. Alternatively you can
18926 also try starting GNOME on Wayland manually from a TTY with the
18927 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
18928 gnome-session``. Currently only GNOME has support for Wayland.
18930 @defvr {Scheme Variable} gnome-desktop-service-type
18931 This is the type of the service that adds the @uref{https://www.gnome.org,
18932 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
18933 object (see below).
18935 This service adds the @code{gnome} package to the system profile, and extends
18936 polkit with the actions from @code{gnome-settings-daemon}.
18939 @deftp {Data Type} gnome-desktop-configuration
18940 Configuration record for the GNOME desktop environment.
18943 @item @code{gnome} (default: @code{gnome})
18944 The GNOME package to use.
18948 @defvr {Scheme Variable} xfce-desktop-service-type
18949 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
18950 desktop environment. Its value is an @code{xfce-desktop-configuration} object
18953 This service adds the @code{xfce} package to the system profile, and
18954 extends polkit with the ability for @code{thunar} to manipulate the file
18955 system as root from within a user session, after the user has authenticated
18956 with the administrator's password.
18958 Note that @code{xfce4-panel} and its plugin packages should be installed in
18959 the same profile to ensure compatibility. When using this service, you should
18960 add extra plugins (@code{xfce4-whiskermenu-plugin},
18961 @code{xfce4-weather-plugin}, etc.) to the @code{packages} field of your
18962 @code{operating-system}.
18965 @deftp {Data Type} xfce-desktop-configuration
18966 Configuration record for the Xfce desktop environment.
18969 @item @code{xfce} (default: @code{xfce})
18970 The Xfce package to use.
18974 @deffn {Scheme Variable} mate-desktop-service-type
18975 This is the type of the service that runs the @uref{https://mate-desktop.org/,
18976 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
18977 object (see below).
18979 This service adds the @code{mate} package to the system
18980 profile, and extends polkit with the actions from
18981 @code{mate-settings-daemon}.
18984 @deftp {Data Type} mate-desktop-configuration
18985 Configuration record for the MATE desktop environment.
18988 @item @code{mate} (default: @code{mate})
18989 The MATE package to use.
18993 @deffn {Scheme Variable} lxqt-desktop-service-type
18994 This is the type of the service that runs the @uref{https://lxqt.github.io,
18995 LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
18996 object (see below).
18998 This service adds the @code{lxqt} package to the system
19002 @deftp {Data Type} lxqt-desktop-configuration
19003 Configuration record for the LXQt desktop environment.
19006 @item @code{lxqt} (default: @code{lxqt})
19007 The LXQT package to use.
19011 @deffn {Scheme Variable} enlightenment-desktop-service-type
19012 Return a service that adds the @code{enlightenment} package to the system
19013 profile, and extends dbus with actions from @code{efl}.
19016 @deftp {Data Type} enlightenment-desktop-service-configuration
19018 @item @code{enlightenment} (default: @code{enlightenment})
19019 The enlightenment package to use.
19023 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
19024 the default @code{%desktop-services} variable doesn't include any of
19025 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
19026 @code{%desktop-services} in the @code{services} field of your
19027 @code{operating-system}:
19030 (use-modules (gnu))
19031 (use-service-modules desktop)
19034 ;; cons* adds items to the list given as its last argument.
19035 (services (cons* (service gnome-desktop-service-type)
19036 (service xfce-desktop-service)
19037 %desktop-services))
19041 These desktop environments will then be available as options in the
19042 graphical login window.
19044 The actual service definitions included in @code{%desktop-services} and
19045 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
19046 are described below.
19048 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
19049 Return a service that runs the ``system bus'', using @var{dbus}, with
19050 support for @var{services}.
19052 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
19053 facility. Its system bus is used to allow system services to communicate
19054 and to be notified of system-wide events.
19056 @var{services} must be a list of packages that provide an
19057 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
19058 and policy files. For example, to allow avahi-daemon to use the system bus,
19059 @var{services} must be equal to @code{(list avahi)}.
19062 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
19063 Return a service that runs the @code{elogind} login and
19064 seat management daemon. @uref{https://github.com/elogind/elogind,
19065 Elogind} exposes a D-Bus interface that can be used to know which users
19066 are logged in, know what kind of sessions they have open, suspend the
19067 system, inhibit system suspend, reboot the system, and other tasks.
19069 Elogind handles most system-level power events for a computer, for
19070 example suspending the system when a lid is closed, or shutting it down
19071 when the power button is pressed.
19073 The @var{config} keyword argument specifies the configuration for
19074 elogind, and should be the result of an @code{(elogind-configuration
19075 (@var{parameter} @var{value})...)} invocation. Available parameters and
19076 their default values are:
19079 @item kill-user-processes?
19081 @item kill-only-users
19083 @item kill-exclude-users
19085 @item inhibit-delay-max-seconds
19087 @item handle-power-key
19089 @item handle-suspend-key
19091 @item handle-hibernate-key
19093 @item handle-lid-switch
19095 @item handle-lid-switch-docked
19097 @item handle-lid-switch-external-power
19099 @item power-key-ignore-inhibited?
19101 @item suspend-key-ignore-inhibited?
19103 @item hibernate-key-ignore-inhibited?
19105 @item lid-switch-ignore-inhibited?
19107 @item holdoff-timeout-seconds
19111 @item idle-action-seconds
19113 @item runtime-directory-size-percent
19115 @item runtime-directory-size
19119 @item suspend-state
19120 @code{("mem" "standby" "freeze")}
19123 @item hibernate-state
19125 @item hibernate-mode
19126 @code{("platform" "shutdown")}
19127 @item hybrid-sleep-state
19129 @item hybrid-sleep-mode
19130 @code{("suspend" "platform" "shutdown")}
19134 @deffn {Scheme Procedure} accountsservice-service @
19135 [#:accountsservice @var{accountsservice}]
19136 Return a service that runs AccountsService, a system service that can
19137 list available accounts, change their passwords, and so on.
19138 AccountsService integrates with PolicyKit to enable unprivileged users
19139 to acquire the capability to modify their system configuration.
19140 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
19141 accountsservice web site} for more information.
19143 The @var{accountsservice} keyword argument is the @code{accountsservice}
19144 package to expose as a service.
19147 @deffn {Scheme Procedure} polkit-service @
19148 [#:polkit @var{polkit}]
19149 Return a service that runs the
19150 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
19151 management service}, which allows system administrators to grant access to
19152 privileged operations in a structured way. By querying the Polkit service, a
19153 privileged system component can know when it should grant additional
19154 capabilities to ordinary users. For example, an ordinary user can be granted
19155 the capability to suspend the system if the user is logged in locally.
19158 @defvr {Scheme Variable} polkit-wheel-service
19159 Service that adds the @code{wheel} group as admins to the Polkit
19160 service. This makes it so that users in the @code{wheel} group are queried
19161 for their own passwords when performing administrative actions instead of
19162 @code{root}'s, similar to the behaviour used by @code{sudo}.
19165 @defvr {Scheme Variable} upower-service-type
19166 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
19167 system-wide monitor for power consumption and battery levels, with the given
19168 configuration settings.
19170 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
19171 notably used by GNOME.
19174 @deftp {Data Type} upower-configuration
19175 Data type representation the configuration for UPower.
19179 @item @code{upower} (default: @var{upower})
19180 Package to use for @code{upower}.
19182 @item @code{watts-up-pro?} (default: @code{#f})
19183 Enable the Watts Up Pro device.
19185 @item @code{poll-batteries?} (default: @code{#t})
19186 Enable polling the kernel for battery level changes.
19188 @item @code{ignore-lid?} (default: @code{#f})
19189 Ignore the lid state, this can be useful if it's incorrect on a device.
19191 @item @code{use-percentage-for-policy?} (default: @code{#f})
19192 Whether battery percentage based policy should be used. The default is to use
19193 the time left, change to @code{#t} to use the percentage.
19195 @item @code{percentage-low} (default: @code{10})
19196 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
19197 at which the battery is considered low.
19199 @item @code{percentage-critical} (default: @code{3})
19200 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
19201 at which the battery is considered critical.
19203 @item @code{percentage-action} (default: @code{2})
19204 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
19205 at which action will be taken.
19207 @item @code{time-low} (default: @code{1200})
19208 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
19209 seconds at which the battery is considered low.
19211 @item @code{time-critical} (default: @code{300})
19212 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
19213 seconds at which the battery is considered critical.
19215 @item @code{time-action} (default: @code{120})
19216 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
19217 seconds at which action will be taken.
19219 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
19220 The action taken when @code{percentage-action} or @code{time-action} is
19221 reached (depending on the configuration of @code{use-percentage-for-policy?}).
19223 Possible values are:
19233 @code{'hybrid-sleep}.
19239 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
19240 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
19241 UDisks}, a @dfn{disk management} daemon that provides user interfaces
19242 with notifications and ways to mount/unmount disks. Programs that talk
19243 to UDisks include the @command{udisksctl} command, part of UDisks, and
19244 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
19245 it will only be able to use the file-system utilities installed in the
19246 system profile. For example if you want to be able to mount NTFS
19247 file-systems in read and write fashion, you'll need to have
19248 @code{ntfs-3g} installed system-wide.
19251 @deffn {Scheme Variable} colord-service-type
19252 This is the type of the service that runs @command{colord}, a system
19253 service with a D-Bus
19254 interface to manage the color profiles of input and output devices such as
19255 screens and scanners. It is notably used by the GNOME Color Manager graphical
19256 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
19257 site} for more information.
19260 @cindex scanner access
19261 @defvr {Scheme Variable} sane-service-type
19262 This service provides access to scanners @i{via}
19263 @uref{http://www.sane-project.org, SANE} by installing the necessary
19264 udev rules. It is included in @code{%desktop-services} (@pxref{Desktop
19265 Services}) and relies by default on @code{sane-backends-minimal} package
19266 (see below) for hardware support.
19269 @defvr {Scheme Variable} sane-backends-minimal
19270 The default package which the @code{sane-service-type} installs. It
19271 supports many recent scanners.
19274 @defvr {Scheme Variable} sane-backends
19275 This package includes support for all scanners that
19276 @code{sane-backends-minimal} supports, plus older Hewlett-Packard
19277 scanners supported by @code{hplip} package. In order to use this on
19278 a system which relies on @code{%desktop-services}, you may use
19279 @code{modify-services} (@pxref{Service Reference,
19280 @code{modify-services}}) as illustrated below:
19283 (use-modules (gnu))
19284 (use-service-modules
19287 (use-package-modules
19291 (define %my-desktop-services
19292 ;; List of desktop services that supports a broader range of scanners.
19293 (modify-services %desktop-services
19294 (sane-service-type _ => sane-backends)))
19298 (services %my-desktop-services)
19302 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
19303 Return a configuration allowing an application to access GeoClue
19304 location data. @var{name} is the Desktop ID of the application, without
19305 the @code{.desktop} part. If @var{allowed?} is true, the application
19306 will have access to location information by default. The boolean
19307 @var{system?} value indicates whether an application is a system component
19308 or not. Finally @var{users} is a list of UIDs of all users for which
19309 this application is allowed location info access. An empty users list
19310 means that all users are allowed.
19313 @defvr {Scheme Variable} %standard-geoclue-applications
19314 The standard list of well-known GeoClue application configurations,
19315 granting authority to the GNOME date-and-time utility to ask for the
19316 current location in order to set the time zone, and allowing the
19317 IceCat and Epiphany web browsers to request location information.
19318 IceCat and Epiphany both query the user before allowing a web page to
19319 know the user's location.
19322 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
19323 [#:whitelist '()] @
19324 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
19325 [#:submit-data? #f]
19326 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
19327 [#:submission-nick "geoclue"] @
19328 [#:applications %standard-geoclue-applications]
19329 Return a service that runs the GeoClue location service. This service
19330 provides a D-Bus interface to allow applications to request access to a
19331 user's physical location, and optionally to add information to online
19332 location databases. See
19333 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
19334 web site} for more information.
19337 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
19338 [@w{#:auto-enable? #f}]
19339 Return a service that runs the @command{bluetoothd} daemon, which
19340 manages all the Bluetooth devices and provides a number of D-Bus
19341 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
19342 powered automatically at boot, which can be useful when using a
19343 bluetooth keyboard or mouse.
19345 Users need to be in the @code{lp} group to access the D-Bus service.
19348 @defvr {Scheme Variable} gnome-keyring-service-type
19349 This is the type of the service that adds the
19350 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
19351 value is a @code{gnome-keyring-configuration} object (see below).
19353 This service adds the @code{gnome-keyring} package to the system profile
19354 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
19355 a user's login keyring when they log in or setting its password with passwd.
19358 @deftp {Data Type} gnome-keyring-configuration
19359 Configuration record for the GNOME Keyring service.
19362 @item @code{keyring} (default: @code{gnome-keyring})
19363 The GNOME keyring package to use.
19365 @item @code{pam-services}
19366 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
19367 services to extend, where @var{service} is the name of an existing
19368 service to extend and @var{kind} is one of @code{login} or
19371 If @code{login} is given, it adds an optional
19372 @code{pam_gnome_keyring.so} to the auth block without arguments and to
19373 the session block with @code{auto_start}. If @code{passwd} is given, it
19374 adds an optional @code{pam_gnome_keyring.so} to the password block
19377 By default, this field contains ``gdm-password'' with the value @code{login}
19378 and ``passwd'' is with the value @code{passwd}.
19383 @node Sound Services
19384 @subsection Sound Services
19386 @cindex sound support
19388 @cindex PulseAudio, sound support
19390 The @code{(gnu services sound)} module provides a service to configure the
19391 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
19392 preferred ALSA output driver.
19394 @deffn {Scheme Variable} alsa-service-type
19395 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
19396 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
19397 configuration file. The value for this type is a @command{alsa-configuration}
19398 record as in this example:
19401 (service alsa-service-type)
19404 See below for details about @code{alsa-configuration}.
19407 @deftp {Data Type} alsa-configuration
19408 Data type representing the configuration for @code{alsa-service}.
19411 @item @code{alsa-plugins} (default: @var{alsa-plugins})
19412 @code{alsa-plugins} package to use.
19414 @item @code{pulseaudio?} (default: @var{#t})
19415 Whether ALSA applications should transparently be made to use the
19416 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
19418 Using PulseAudio allows you to run several sound-producing applications
19419 at the same time and to individual control them @i{via}
19420 @command{pavucontrol}, among other things.
19422 @item @code{extra-options} (default: @var{""})
19423 String to append to the @file{/etc/asound.conf} file.
19428 Individual users who want to override the system configuration of ALSA can do
19429 it with the @file{~/.asoundrc} file:
19432 # In guix, we have to specify the absolute path for plugins.
19434 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
19437 # Routing ALSA to jack:
19438 # <http://jackaudio.org/faq/routing_alsa.html>.
19442 0 system:playback_1
19443 1 system:playback_2
19460 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
19463 @deffn {Scheme Variable} pulseaudio-service-type
19464 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
19465 sound server. It exists to allow system overrides of the default settings
19466 via @code{pulseaudio-configuration}, see below.
19469 This service overrides per-user configuration files. If you want
19470 PulseAudio to honor configuration files in @file{~/.config/pulse} you
19471 have to unset the environment variables @env{PULSE_CONFIG} and
19472 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
19476 This service on its own does not ensure, that the @code{pulseaudio} package
19477 exists on your machine. It merely adds configuration files for it, as
19478 detailed below. In the (admittedly unlikely) case, that you find yourself
19479 without a @code{pulseaudio} package, consider enabling it through the
19480 @code{alsa-service-type} above.
19484 @deftp {Data Type} pulseaudio-configuration
19485 Data type representing the configuration for @code{pulseaudio-service}.
19488 @item @code{client-conf} (default: @code{'()})
19489 List of settings to set in @file{client.conf}.
19490 Accepts a list of strings or a symbol-value pairs. A string will be
19491 inserted as-is with a newline added. A pair will be formatted as
19492 ``key = value'', again with a newline added.
19494 @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
19495 List of settings to set in @file{daemon.conf}, formatted just like
19498 @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
19499 Script file to use as @file{default.pa}.
19501 @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
19502 Script file to use as @file{system.pa}.
19506 @deffn {Scheme Variable} ladspa-service-type
19507 This service sets the @var{LADSPA_PATH} variable, so that programs, which
19508 respect it, e.g. PulseAudio, can load LADSPA plugins.
19510 The following example will setup the service to enable modules from the
19511 @code{swh-plugins} package:
19514 (service ladspa-service-type
19515 (ladspa-configuration (plugins (list swh-plugins))))
19518 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
19523 @node Database Services
19524 @subsection Database Services
19528 The @code{(gnu services databases)} module provides the following services.
19530 @subsubheading PostgreSQL
19532 The following example describes a PostgreSQL service with the default
19536 (service postgresql-service-type
19537 (postgresql-configuration
19538 (postgresql postgresql-10)))
19541 If the services fails to start, it may be due to an incompatible
19542 cluster already present in @var{data-directory}. Adjust it (or, if you
19543 don't need the cluster anymore, delete @var{data-directory}), then
19544 restart the service.
19546 Peer authentication is used by default and the @code{postgres} user
19547 account has no shell, which prevents the direct execution of @code{psql}
19548 commands as this user. To use @code{psql}, you can temporarily log in
19549 as @code{postgres} using a shell, create a PostgreSQL superuser with the
19550 same name as one of the system users and then create the associated
19554 sudo -u postgres -s /bin/sh
19555 createuser --interactive
19556 createdb $MY_USER_LOGIN # Replace appropriately.
19559 @deftp {Data Type} postgresql-configuration
19560 Data type representing the configuration for the
19561 @code{postgresql-service-type}.
19564 @item @code{postgresql}
19565 PostgreSQL package to use for the service.
19567 @item @code{port} (default: @code{5432})
19568 Port on which PostgreSQL should listen.
19570 @item @code{locale} (default: @code{"en_US.utf8"})
19571 Locale to use as the default when creating the database cluster.
19573 @item @code{config-file} (default: @code{(postgresql-config-file)})
19574 The configuration file to use when running PostgreSQL@. The default
19575 behaviour uses the postgresql-config-file record with the default values
19578 @item @code{log-directory} (default: @code{"/var/log/postgresql"})
19579 The directory where @command{pg_ctl} output will be written in a file
19580 named @code{"pg_ctl.log"}. This file can be useful to debug PostgreSQL
19581 configuration errors for instance.
19583 @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
19584 Directory in which to store the data.
19586 @item @code{extension-packages} (default: @code{'()})
19587 @cindex postgresql extension-packages
19588 Additional extensions are loaded from packages listed in
19589 @var{extension-packages}. Extensions are available at runtime. For instance,
19590 to create a geographic database using the @code{postgis} extension, a user can
19591 configure the postgresql-service as in this example:
19595 (use-package-modules databases geo)
19599 ;; postgresql is required to run `psql' but postgis is not required for
19600 ;; proper operation.
19601 (packages (cons* postgresql %base-packages))
19604 (service postgresql-service-type
19605 (postgresql-configuration
19606 (postgresql postgresql-10)
19607 (extension-packages (list postgis))))
19611 Then the extension becomes visible and you can initialise an empty geographic
19612 database in this way:
19616 > create database postgistest;
19617 > \connect postgistest;
19618 > create extension postgis;
19619 > create extension postgis_topology;
19622 There is no need to add this field for contrib extensions such as hstore or
19623 dblink as they are already loadable by postgresql. This field is only
19624 required to add extensions provided by other packages.
19629 @deftp {Data Type} postgresql-config-file
19630 Data type representing the PostgreSQL configuration file. As shown in
19631 the following example, this can be used to customize the configuration
19632 of PostgreSQL@. Note that you can use any G-expression or filename in
19633 place of this record, if you already have a configuration file you'd
19634 like to use for example.
19637 (service postgresql-service-type
19638 (postgresql-configuration
19640 (postgresql-config-file
19641 (log-destination "stderr")
19643 (plain-file "pg_hba.conf"
19645 local all all trust
19646 host all all 127.0.0.1/32 md5
19647 host all all ::1/128 md5"))
19649 '(("session_preload_libraries" "auto_explain")
19650 ("random_page_cost" 2)
19651 ("auto_explain.log_min_duration" "100 ms")
19652 ("work_mem" "500 MB")
19653 ("logging_collector" #t)
19654 ("log_directory" "/var/log/postgresql")))))))
19658 @item @code{log-destination} (default: @code{"syslog"})
19659 The logging method to use for PostgreSQL@. Multiple values are accepted,
19660 separated by commas.
19662 @item @code{hba-file} (default: @code{%default-postgres-hba})
19663 Filename or G-expression for the host-based authentication
19666 @item @code{ident-file} (default: @code{%default-postgres-ident})
19667 Filename or G-expression for the user name mapping configuration.
19669 @item @code{socket-directory} (default: @code{"/var/run/postgresql"})
19670 Specifies the directory of the Unix-domain socket(s) on which PostgreSQL
19671 is to listen for connections from client applications. If set to
19672 @code{#false} PostgreSQL does not listen on any Unix-domain sockets, in
19673 which case only TCP/IP sockets can be used to connect to the server.
19675 @item @code{extra-config} (default: @code{'()})
19676 List of additional keys and values to include in the PostgreSQL config
19677 file. Each entry in the list should be a list where the first element
19678 is the key, and the remaining elements are the values.
19680 The values can be numbers, booleans or strings and will be mapped to
19681 PostgreSQL parameters types @code{Boolean}, @code{String},
19682 @code{Numeric}, @code{Numeric with Unit} and @code{Enumerated} described
19683 @uref{https://www.postgresql.org/docs/current/config-setting.html,
19689 @deffn {Scheme Variable} postgresql-role-service-type
19690 This service allows to create PostgreSQL roles and databases after
19691 PostgreSQL service start. Here is an example of its use.
19694 (service postgresql-role-service-type
19695 (postgresql-role-configuration
19697 (list (postgresql-role
19699 (create-database? #t))))))
19702 This service can be extended with extra roles, as in this
19706 (service-extension postgresql-role-service-type
19707 (const (postgresql-role
19709 (create-database? #t))))
19713 @deftp {Data Type} postgresql-role
19714 PostgreSQL manages database access permissions using the concept of
19715 roles. A role can be thought of as either a database user, or a group
19716 of database users, depending on how the role is set up. Roles can own
19717 database objects (for example, tables) and can assign privileges on
19718 those objects to other roles to control who has access to which objects.
19724 @item @code{permissions} (default: @code{'(createdb login)})
19725 The role permissions list. Supported permissions are @code{bypassrls},
19726 @code{createdb}, @code{createrole}, @code{login}, @code{replication} and
19729 @item @code{create-database?} (default: @code{#f})
19730 Whether to create a database with the same name as the role.
19735 @deftp {Data Type} postgresql-role-configuration
19736 Data type representing the configuration of
19737 @var{postgresql-role-service-type}.
19740 @item @code{host} (default: @code{"/var/run/postgresql"})
19741 The PostgreSQL host to connect to.
19743 @item @code{log} (default: @code{"/var/log/postgresql_roles.log"})
19744 File name of the log file.
19746 @item @code{roles} (default: @code{'()})
19747 The initial PostgreSQL roles to create.
19751 @subsubheading MariaDB/MySQL
19753 @defvr {Scheme Variable} mysql-service-type
19754 This is the service type for a MySQL or MariaDB database server. Its value
19755 is a @code{mysql-configuration} object that specifies which package to use,
19756 as well as various settings for the @command{mysqld} daemon.
19759 @deftp {Data Type} mysql-configuration
19760 Data type representing the configuration of @var{mysql-service-type}.
19763 @item @code{mysql} (default: @var{mariadb})
19764 Package object of the MySQL database server, can be either @var{mariadb}
19767 For MySQL, a temporary root password will be displayed at activation time.
19768 For MariaDB, the root password is empty.
19770 @item @code{bind-address} (default: @code{"127.0.0.1"})
19771 The IP on which to listen for network connections. Use @code{"0.0.0.0"}
19772 to bind to all available network interfaces.
19774 @item @code{port} (default: @code{3306})
19775 TCP port on which the database server listens for incoming connections.
19777 @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
19778 Socket file to use for local (non-network) connections.
19780 @item @code{extra-content} (default: @code{""})
19781 Additional settings for the @file{my.cnf} configuration file.
19783 @item @code{auto-upgrade?} (default: @code{#t})
19784 Whether to automatically run @command{mysql_upgrade} after starting the
19785 service. This is necessary to upgrade the @dfn{system schema} after
19786 ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
19787 be disabled if you would rather do that manually.
19792 @subsubheading Memcached
19794 @defvr {Scheme Variable} memcached-service-type
19795 This is the service type for the @uref{https://memcached.org/,
19796 Memcached} service, which provides a distributed in memory cache. The
19797 value for the service type is a @code{memcached-configuration} object.
19801 (service memcached-service-type)
19804 @deftp {Data Type} memcached-configuration
19805 Data type representing the configuration of memcached.
19808 @item @code{memcached} (default: @code{memcached})
19809 The Memcached package to use.
19811 @item @code{interfaces} (default: @code{'("0.0.0.0")})
19812 Network interfaces on which to listen.
19814 @item @code{tcp-port} (default: @code{11211})
19815 Port on which to accept connections.
19817 @item @code{udp-port} (default: @code{11211})
19818 Port on which to accept UDP connections on, a value of 0 will disable
19819 listening on a UDP socket.
19821 @item @code{additional-options} (default: @code{'()})
19822 Additional command line options to pass to @code{memcached}.
19826 @subsubheading Redis
19828 @defvr {Scheme Variable} redis-service-type
19829 This is the service type for the @uref{https://redis.io/, Redis}
19830 key/value store, whose value is a @code{redis-configuration} object.
19833 @deftp {Data Type} redis-configuration
19834 Data type representing the configuration of redis.
19837 @item @code{redis} (default: @code{redis})
19838 The Redis package to use.
19840 @item @code{bind} (default: @code{"127.0.0.1"})
19841 Network interface on which to listen.
19843 @item @code{port} (default: @code{6379})
19844 Port on which to accept connections on, a value of 0 will disable
19845 listening on a TCP socket.
19847 @item @code{working-directory} (default: @code{"/var/lib/redis"})
19848 Directory in which to store the database and related files.
19852 @node Mail Services
19853 @subsection Mail Services
19857 The @code{(gnu services mail)} module provides Guix service definitions
19858 for email services: IMAP, POP3, and LMTP servers, as well as mail
19859 transport agents (MTAs). Lots of acronyms! These services are detailed
19860 in the subsections below.
19862 @subsubheading Dovecot Service
19864 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
19865 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
19868 By default, Dovecot does not need much configuration; the default
19869 configuration object created by @code{(dovecot-configuration)} will
19870 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
19871 certificate will be generated for TLS-protected connections, though
19872 Dovecot will also listen on cleartext ports by default. There are a
19873 number of options, though, which mail administrators might need to change,
19874 and as is the case with other services, Guix allows the system
19875 administrator to specify these parameters via a uniform Scheme interface.
19877 For example, to specify that mail is located at @code{maildir~/.mail},
19878 one would instantiate the Dovecot service like this:
19881 (dovecot-service #:config
19882 (dovecot-configuration
19883 (mail-location "maildir:~/.mail")))
19886 The available configuration parameters follow. Each parameter
19887 definition is preceded by its type; for example, @samp{string-list foo}
19888 indicates that the @code{foo} parameter should be specified as a list of
19889 strings. There is also a way to specify the configuration as a string,
19890 if you have an old @code{dovecot.conf} file that you want to port over
19891 from some other system; see the end for more details.
19893 @c The following documentation was initially generated by
19894 @c (generate-documentation) in (gnu services mail). Manually maintained
19895 @c documentation is better, so we shouldn't hesitate to edit below as
19896 @c needed. However if the change you want to make to this documentation
19897 @c can be done in an automated way, it's probably easier to change
19898 @c (generate-documentation) than to make it below and have to deal with
19899 @c the churn as dovecot updates.
19901 Available @code{dovecot-configuration} fields are:
19903 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
19904 The dovecot package.
19907 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
19908 A list of IPs or hosts where to listen for connections. @samp{*}
19909 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
19910 interfaces. If you want to specify non-default ports or anything more
19911 complex, customize the address and port fields of the
19912 @samp{inet-listener} of the specific services you are interested in.
19915 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
19916 List of protocols we want to serve. Available protocols include
19917 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
19919 Available @code{protocol-configuration} fields are:
19921 @deftypevr {@code{protocol-configuration} parameter} string name
19922 The name of the protocol.
19925 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
19926 UNIX socket path to the master authentication server to find users.
19927 This is used by imap (for shared users) and lda.
19928 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
19931 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
19932 Space separated list of plugins to load.
19935 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
19936 Maximum number of IMAP connections allowed for a user from each IP
19937 address. NOTE: The username is compared case-sensitively.
19938 Defaults to @samp{10}.
19943 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
19944 List of services to enable. Available services include @samp{imap},
19945 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
19948 Available @code{service-configuration} fields are:
19950 @deftypevr {@code{service-configuration} parameter} string kind
19951 The service kind. Valid values include @code{director},
19952 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
19953 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
19954 @code{tcpwrap}, @code{quota-warning}, or anything else.
19957 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
19958 Listeners for the service. A listener is either a
19959 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
19960 an @code{inet-listener-configuration}.
19961 Defaults to @samp{()}.
19963 Available @code{unix-listener-configuration} fields are:
19965 @deftypevr {@code{unix-listener-configuration} parameter} string path
19966 Path to the file, relative to @code{base-dir} field. This is also used as
19970 @deftypevr {@code{unix-listener-configuration} parameter} string mode
19971 The access mode for the socket.
19972 Defaults to @samp{"0600"}.
19975 @deftypevr {@code{unix-listener-configuration} parameter} string user
19976 The user to own the socket.
19977 Defaults to @samp{""}.
19980 @deftypevr {@code{unix-listener-configuration} parameter} string group
19981 The group to own the socket.
19982 Defaults to @samp{""}.
19986 Available @code{fifo-listener-configuration} fields are:
19988 @deftypevr {@code{fifo-listener-configuration} parameter} string path
19989 Path to the file, relative to @code{base-dir} field. This is also used as
19993 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
19994 The access mode for the socket.
19995 Defaults to @samp{"0600"}.
19998 @deftypevr {@code{fifo-listener-configuration} parameter} string user
19999 The user to own the socket.
20000 Defaults to @samp{""}.
20003 @deftypevr {@code{fifo-listener-configuration} parameter} string group
20004 The group to own the socket.
20005 Defaults to @samp{""}.
20009 Available @code{inet-listener-configuration} fields are:
20011 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
20012 The protocol to listen for.
20015 @deftypevr {@code{inet-listener-configuration} parameter} string address
20016 The address on which to listen, or empty for all addresses.
20017 Defaults to @samp{""}.
20020 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
20021 The port on which to listen.
20024 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
20025 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
20027 Defaults to @samp{#t}.
20032 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
20033 Maximum number of simultaneous client connections per process. Once
20034 this number of connections is received, the next incoming connection
20035 will prompt Dovecot to spawn another process. If set to 0,
20036 @code{default-client-limit} is used instead.
20038 Defaults to @samp{0}.
20042 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
20043 Number of connections to handle before starting a new process.
20044 Typically the only useful values are 0 (unlimited) or 1. 1 is more
20045 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
20046 Defaults to @samp{1}.
20050 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
20051 Maximum number of processes that can exist for this service. If set to
20052 0, @code{default-process-limit} is used instead.
20054 Defaults to @samp{0}.
20058 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
20059 Number of processes to always keep waiting for more connections.
20060 Defaults to @samp{0}.
20063 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
20064 If you set @samp{service-count 0}, you probably need to grow
20066 Defaults to @samp{256000000}.
20071 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
20072 Dict configuration, as created by the @code{dict-configuration}
20075 Available @code{dict-configuration} fields are:
20077 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
20078 A list of key-value pairs that this dict should hold.
20079 Defaults to @samp{()}.
20084 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
20085 A list of passdb configurations, each one created by the
20086 @code{passdb-configuration} constructor.
20088 Available @code{passdb-configuration} fields are:
20090 @deftypevr {@code{passdb-configuration} parameter} string driver
20091 The driver that the passdb should use. Valid values include
20092 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
20094 Defaults to @samp{"pam"}.
20097 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
20098 Space separated list of arguments to the passdb driver.
20099 Defaults to @samp{""}.
20104 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
20105 List of userdb configurations, each one created by the
20106 @code{userdb-configuration} constructor.
20108 Available @code{userdb-configuration} fields are:
20110 @deftypevr {@code{userdb-configuration} parameter} string driver
20111 The driver that the userdb should use. Valid values include
20112 @samp{passwd} and @samp{static}.
20113 Defaults to @samp{"passwd"}.
20116 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
20117 Space separated list of arguments to the userdb driver.
20118 Defaults to @samp{""}.
20121 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
20122 Override fields from passwd.
20123 Defaults to @samp{()}.
20128 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
20129 Plug-in configuration, created by the @code{plugin-configuration}
20133 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
20134 List of namespaces. Each item in the list is created by the
20135 @code{namespace-configuration} constructor.
20137 Available @code{namespace-configuration} fields are:
20139 @deftypevr {@code{namespace-configuration} parameter} string name
20140 Name for this namespace.
20143 @deftypevr {@code{namespace-configuration} parameter} string type
20144 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
20145 Defaults to @samp{"private"}.
20148 @deftypevr {@code{namespace-configuration} parameter} string separator
20149 Hierarchy separator to use. You should use the same separator for
20150 all namespaces or some clients get confused. @samp{/} is usually a good
20151 one. The default however depends on the underlying mail storage
20153 Defaults to @samp{""}.
20156 @deftypevr {@code{namespace-configuration} parameter} string prefix
20157 Prefix required to access this namespace. This needs to be
20158 different for all namespaces. For example @samp{Public/}.
20159 Defaults to @samp{""}.
20162 @deftypevr {@code{namespace-configuration} parameter} string location
20163 Physical location of the mailbox. This is in the same format as
20164 mail_location, which is also the default for it.
20165 Defaults to @samp{""}.
20168 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
20169 There can be only one INBOX, and this setting defines which
20171 Defaults to @samp{#f}.
20174 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
20175 If namespace is hidden, it's not advertised to clients via NAMESPACE
20176 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
20177 useful when converting from another server with different namespaces
20178 which you want to deprecate but still keep working. For example you can
20179 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
20181 Defaults to @samp{#f}.
20184 @deftypevr {@code{namespace-configuration} parameter} boolean list?
20185 Show the mailboxes under this namespace with the LIST command. This
20186 makes the namespace visible for clients that do not support the NAMESPACE
20187 extension. The special @code{children} value lists child mailboxes, but
20188 hides the namespace prefix.
20189 Defaults to @samp{#t}.
20192 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
20193 Namespace handles its own subscriptions. If set to @code{#f}, the
20194 parent namespace handles them. The empty prefix should always have this
20196 Defaults to @samp{#t}.
20199 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
20200 List of predefined mailboxes in this namespace.
20201 Defaults to @samp{()}.
20203 Available @code{mailbox-configuration} fields are:
20205 @deftypevr {@code{mailbox-configuration} parameter} string name
20206 Name for this mailbox.
20209 @deftypevr {@code{mailbox-configuration} parameter} string auto
20210 @samp{create} will automatically create this mailbox.
20211 @samp{subscribe} will both create and subscribe to the mailbox.
20212 Defaults to @samp{"no"}.
20215 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
20216 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
20217 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
20218 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
20219 Defaults to @samp{()}.
20226 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
20227 Base directory where to store runtime data.
20228 Defaults to @samp{"/var/run/dovecot/"}.
20231 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
20232 Greeting message for clients.
20233 Defaults to @samp{"Dovecot ready."}.
20236 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
20237 List of trusted network ranges. Connections from these IPs are
20238 allowed to override their IP addresses and ports (for logging and for
20239 authentication checks). @samp{disable-plaintext-auth} is also ignored
20240 for these networks. Typically you would specify your IMAP proxy servers
20242 Defaults to @samp{()}.
20245 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
20246 List of login access check sockets (e.g.@: tcpwrap).
20247 Defaults to @samp{()}.
20250 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
20251 Show more verbose process titles (in ps). Currently shows user name
20252 and IP address. Useful for seeing who is actually using the IMAP
20253 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
20255 Defaults to @samp{#f}.
20258 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
20259 Should all processes be killed when Dovecot master process shuts down.
20260 Setting this to @code{#f} means that Dovecot can be upgraded without
20261 forcing existing client connections to close (although that could also
20262 be a problem if the upgrade is e.g.@: due to a security fix).
20263 Defaults to @samp{#t}.
20266 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
20267 If non-zero, run mail commands via this many connections to doveadm
20268 server, instead of running them directly in the same process.
20269 Defaults to @samp{0}.
20272 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
20273 UNIX socket or host:port used for connecting to doveadm server.
20274 Defaults to @samp{"doveadm-server"}.
20277 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
20278 List of environment variables that are preserved on Dovecot startup
20279 and passed down to all of its child processes. You can also give
20280 key=value pairs to always set specific settings.
20283 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
20284 Disable LOGIN command and all other plaintext authentications unless
20285 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
20286 matches the local IP (i.e.@: you're connecting from the same computer),
20287 the connection is considered secure and plaintext authentication is
20288 allowed. See also ssl=required setting.
20289 Defaults to @samp{#t}.
20292 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
20293 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
20294 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
20295 for caching to be used.
20296 Defaults to @samp{0}.
20299 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
20300 Time to live for cached data. After TTL expires the cached record
20301 is no longer used, *except* if the main database lookup returns internal
20302 failure. We also try to handle password changes automatically: If
20303 user's previous authentication was successful, but this one wasn't, the
20304 cache isn't used. For now this works only with plaintext
20306 Defaults to @samp{"1 hour"}.
20309 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
20310 TTL for negative hits (user not found, password mismatch).
20311 0 disables caching them completely.
20312 Defaults to @samp{"1 hour"}.
20315 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
20316 List of realms for SASL authentication mechanisms that need them.
20317 You can leave it empty if you don't want to support multiple realms.
20318 Many clients simply use the first one listed here, so keep the default
20320 Defaults to @samp{()}.
20323 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
20324 Default realm/domain to use if none was specified. This is used for
20325 both SASL realms and appending @@domain to username in plaintext
20327 Defaults to @samp{""}.
20330 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
20331 List of allowed characters in username. If the user-given username
20332 contains a character not listed in here, the login automatically fails.
20333 This is just an extra check to make sure user can't exploit any
20334 potential quote escaping vulnerabilities with SQL/LDAP databases. If
20335 you want to allow all characters, set this value to empty.
20336 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
20339 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
20340 Username character translations before it's looked up from
20341 databases. The value contains series of from -> to characters. For
20342 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
20343 translated to @samp{@@}.
20344 Defaults to @samp{""}.
20347 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
20348 Username formatting before it's looked up from databases. You can
20349 use the standard variables here, e.g.@: %Lu would lowercase the username,
20350 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
20351 change the @samp{@@} into @samp{-AT-}. This translation is done after
20352 @samp{auth-username-translation} changes.
20353 Defaults to @samp{"%Lu"}.
20356 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
20357 If you want to allow master users to log in by specifying the master
20358 username within the normal username string (i.e.@: not using SASL
20359 mechanism's support for it), you can specify the separator character
20360 here. The format is then <username><separator><master username>.
20361 UW-IMAP uses @samp{*} as the separator, so that could be a good
20363 Defaults to @samp{""}.
20366 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
20367 Username to use for users logging in with ANONYMOUS SASL
20369 Defaults to @samp{"anonymous"}.
20372 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
20373 Maximum number of dovecot-auth worker processes. They're used to
20374 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
20375 They're automatically created and destroyed as needed.
20376 Defaults to @samp{30}.
20379 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
20380 Host name to use in GSSAPI principal names. The default is to use
20381 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
20382 allow all keytab entries.
20383 Defaults to @samp{""}.
20386 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
20387 Kerberos keytab to use for the GSSAPI mechanism. Will use the
20388 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
20389 need to change the auth service to run as root to be able to read this
20391 Defaults to @samp{""}.
20394 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
20395 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
20396 and @samp{ntlm-auth} helper.
20397 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
20398 Defaults to @samp{#f}.
20401 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
20402 Path for Samba's @samp{ntlm-auth} helper binary.
20403 Defaults to @samp{"/usr/bin/ntlm_auth"}.
20406 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
20407 Time to delay before replying to failed authentications.
20408 Defaults to @samp{"2 secs"}.
20411 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
20412 Require a valid SSL client certificate or the authentication
20414 Defaults to @samp{#f}.
20417 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
20418 Take the username from client's SSL certificate, using
20419 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
20421 Defaults to @samp{#f}.
20424 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
20425 List of wanted authentication mechanisms. Supported mechanisms are:
20426 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
20427 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
20428 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
20429 @samp{disable-plaintext-auth} setting.
20432 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
20433 List of IPs or hostnames to all director servers, including ourself.
20434 Ports can be specified as ip:port. The default port is the same as what
20435 director service's @samp{inet-listener} is using.
20436 Defaults to @samp{()}.
20439 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
20440 List of IPs or hostnames to all backend mail servers. Ranges are
20441 allowed too, like 10.0.0.10-10.0.0.30.
20442 Defaults to @samp{()}.
20445 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
20446 How long to redirect users to a specific server after it no longer
20447 has any connections.
20448 Defaults to @samp{"15 min"}.
20451 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
20452 How the username is translated before being hashed. Useful values
20453 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
20454 are shared within domain.
20455 Defaults to @samp{"%Lu"}.
20458 @deftypevr {@code{dovecot-configuration} parameter} string log-path
20459 Log file to use for error messages. @samp{syslog} logs to syslog,
20460 @samp{/dev/stderr} logs to stderr.
20461 Defaults to @samp{"syslog"}.
20464 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
20465 Log file to use for informational messages. Defaults to
20467 Defaults to @samp{""}.
20470 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
20471 Log file to use for debug messages. Defaults to
20472 @samp{info-log-path}.
20473 Defaults to @samp{""}.
20476 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
20477 Syslog facility to use if you're logging to syslog. Usually if you
20478 don't want to use @samp{mail}, you'll use local0..local7. Also other
20479 standard facilities are supported.
20480 Defaults to @samp{"mail"}.
20483 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
20484 Log unsuccessful authentication attempts and the reasons why they
20486 Defaults to @samp{#f}.
20489 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
20490 In case of password mismatches, log the attempted password. Valid
20491 values are no, plain and sha1. sha1 can be useful for detecting brute
20492 force password attempts vs. user simply trying the same password over
20493 and over again. You can also truncate the value to n chars by appending
20494 ":n" (e.g.@: sha1:6).
20495 Defaults to @samp{"no"}.
20498 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
20499 Even more verbose logging for debugging purposes. Shows for example
20501 Defaults to @samp{#f}.
20504 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
20505 In case of password mismatches, log the passwords and used scheme so
20506 the problem can be debugged. Enabling this also enables
20508 Defaults to @samp{#f}.
20511 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
20512 Enable mail process debugging. This can help you figure out why
20513 Dovecot isn't finding your mails.
20514 Defaults to @samp{#f}.
20517 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
20518 Show protocol level SSL errors.
20519 Defaults to @samp{#f}.
20522 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
20523 Prefix for each line written to log file. % codes are in
20524 strftime(3) format.
20525 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
20528 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
20529 List of elements we want to log. The elements which have a
20530 non-empty variable value are joined together to form a comma-separated
20534 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
20535 Login log format. %s contains @samp{login-log-format-elements}
20536 string, %$ contains the data we want to log.
20537 Defaults to @samp{"%$: %s"}.
20540 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
20541 Log prefix for mail processes. See doc/wiki/Variables.txt for list
20542 of possible variables you can use.
20543 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
20546 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
20547 Format to use for logging mail deliveries. You can use variables:
20550 Delivery status message (e.g.@: @samp{saved to INBOX})
20562 Defaults to @samp{"msgid=%m: %$"}.
20565 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
20566 Location for users' mailboxes. The default is empty, which means
20567 that Dovecot tries to find the mailboxes automatically. This won't work
20568 if the user doesn't yet have any mail, so you should explicitly tell
20569 Dovecot the full location.
20571 If you're using mbox, giving a path to the INBOX
20572 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
20573 where the other mailboxes are kept. This is called the @emph{root mail
20574 directory}, and it must be the first path given in the
20575 @samp{mail-location} setting.
20577 There are a few special variables you can use, e.g.:
20583 user part in user@@domain, same as %u if there's no domain
20585 domain part in user@@domain, empty if there's no domain
20590 See doc/wiki/Variables.txt for full list. Some examples:
20592 @item maildir:~/Maildir
20593 @item mbox:~/mail:INBOX=/var/mail/%u
20594 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
20596 Defaults to @samp{""}.
20599 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
20600 System user and group used to access mails. If you use multiple,
20601 userdb can override these by returning uid or gid fields. You can use
20602 either numbers or names. <doc/wiki/UserIds.txt>.
20603 Defaults to @samp{""}.
20606 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
20608 Defaults to @samp{""}.
20611 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
20612 Group to enable temporarily for privileged operations. Currently
20613 this is used only with INBOX when either its initial creation or
20614 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
20616 Defaults to @samp{""}.
20619 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
20620 Grant access to these supplementary groups for mail processes.
20621 Typically these are used to set up access to shared mailboxes. Note
20622 that it may be dangerous to set these if users can create symlinks
20623 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
20624 could allow a user to delete others' mailboxes, or @code{ln -s
20625 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
20629 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
20630 Allow full file system access to clients. There's no access checks
20631 other than what the operating system does for the active UID/GID@. It
20632 works with both maildir and mboxes, allowing you to prefix mailboxes
20633 names with e.g.@: @file{/path/} or @file{~user/}.
20634 Defaults to @samp{#f}.
20637 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
20638 Don't use @code{mmap()} at all. This is required if you store indexes to
20639 shared file systems (NFS or clustered file system).
20640 Defaults to @samp{#f}.
20643 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
20644 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
20645 supports @samp{O_EXCL} since version 3, so this should be safe to use
20646 nowadays by default.
20647 Defaults to @samp{#t}.
20650 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
20651 When to use fsync() or fdatasync() calls:
20654 Whenever necessary to avoid losing important data
20656 Useful with e.g.@: NFS when @code{write()}s are delayed
20658 Never use it (best performance, but crashes can lose data).
20660 Defaults to @samp{"optimized"}.
20663 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
20664 Mail storage exists in NFS@. Set this to yes to make Dovecot flush
20665 NFS caches whenever needed. If you're using only a single mail server
20667 Defaults to @samp{#f}.
20670 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
20671 Mail index files also exist in NFS@. Setting this to yes requires
20672 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
20673 Defaults to @samp{#f}.
20676 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
20677 Locking method for index files. Alternatives are fcntl, flock and
20678 dotlock. Dotlocking uses some tricks which may create more disk I/O
20679 than other locking methods. NFS users: flock doesn't work, remember to
20680 change @samp{mmap-disable}.
20681 Defaults to @samp{"fcntl"}.
20684 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
20685 Directory in which LDA/LMTP temporarily stores incoming mails >128
20687 Defaults to @samp{"/tmp"}.
20690 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
20691 Valid UID range for users. This is mostly to make sure that users can't
20692 log in as daemons or other system users. Note that denying root logins is
20693 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
20695 Defaults to @samp{500}.
20698 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
20700 Defaults to @samp{0}.
20703 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
20704 Valid GID range for users. Users having non-valid GID as primary group ID
20705 aren't allowed to log in. If user belongs to supplementary groups with
20706 non-valid GIDs, those groups are not set.
20707 Defaults to @samp{1}.
20710 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
20712 Defaults to @samp{0}.
20715 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
20716 Maximum allowed length for mail keyword name. It's only forced when
20717 trying to create new keywords.
20718 Defaults to @samp{50}.
20721 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
20722 List of directories under which chrooting is allowed for mail
20723 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
20724 too). This setting doesn't affect @samp{login-chroot}
20725 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
20726 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
20727 which local users can modify, that may lead to root exploit. Usually
20728 this should be done only if you don't allow shell access for users.
20729 <doc/wiki/Chrooting.txt>.
20730 Defaults to @samp{()}.
20733 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
20734 Default chroot directory for mail processes. This can be overridden
20735 for specific users in user database by giving @samp{/./} in user's home
20736 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
20737 there is no real need to do chrooting, Dovecot doesn't allow users to
20738 access files outside their mail directory anyway. If your home
20739 directories are prefixed with the chroot directory, append @samp{/.} to
20740 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
20741 Defaults to @samp{""}.
20744 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
20745 UNIX socket path to master authentication server to find users.
20746 This is used by imap (for shared users) and lda.
20747 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
20750 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
20751 Directory where to look up mail plugins.
20752 Defaults to @samp{"/usr/lib/dovecot"}.
20755 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
20756 List of plugins to load for all services. Plugins specific to IMAP,
20757 LDA, etc.@: are added to this list in their own .conf files.
20758 Defaults to @samp{()}.
20761 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
20762 The minimum number of mails in a mailbox before updates are done to
20763 cache file. This allows optimizing Dovecot's behavior to do less disk
20764 writes at the cost of more disk reads.
20765 Defaults to @samp{0}.
20768 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
20769 When IDLE command is running, mailbox is checked once in a while to
20770 see if there are any new mails or other changes. This setting defines
20771 the minimum time to wait between those checks. Dovecot can also use
20772 dnotify, inotify and kqueue to find out immediately when changes
20774 Defaults to @samp{"30 secs"}.
20777 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
20778 Save mails with CR+LF instead of plain LF@. This makes sending those
20779 mails take less CPU, especially with sendfile() syscall with Linux and
20780 FreeBSD@. But it also creates a bit more disk I/O which may just make it
20781 slower. Also note that if other software reads the mboxes/maildirs,
20782 they may handle the extra CRs wrong and cause problems.
20783 Defaults to @samp{#f}.
20786 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
20787 By default LIST command returns all entries in maildir beginning
20788 with a dot. Enabling this option makes Dovecot return only entries
20789 which are directories. This is done by stat()ing each entry, so it
20790 causes more disk I/O.
20791 (For systems setting struct @samp{dirent->d_type} this check is free
20792 and it's done always regardless of this setting).
20793 Defaults to @samp{#f}.
20796 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
20797 When copying a message, do it with hard links whenever possible.
20798 This makes the performance much better, and it's unlikely to have any
20800 Defaults to @samp{#t}.
20803 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
20804 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
20805 directory only when its mtime changes unexpectedly or when we can't find
20806 the mail otherwise.
20807 Defaults to @samp{#f}.
20810 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
20811 Which locking methods to use for locking mbox. There are four
20816 Create <mailbox>.lock file. This is the oldest and most NFS-safe
20817 solution. If you want to use /var/mail/ like directory, the users will
20818 need write access to that directory.
20820 Same as dotlock, but if it fails because of permissions or because there
20821 isn't enough disk space, just skip it.
20823 Use this if possible. Works with NFS too if lockd is used.
20825 May not exist in all systems. Doesn't work with NFS.
20827 May not exist in all systems. Doesn't work with NFS.
20830 You can use multiple locking methods; if you do the order they're declared
20831 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
20832 locking methods as well. Some operating systems don't allow using some of
20833 them simultaneously.
20836 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
20840 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
20841 Maximum time to wait for lock (all of them) before aborting.
20842 Defaults to @samp{"5 mins"}.
20845 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
20846 If dotlock exists but the mailbox isn't modified in any way,
20847 override the lock file after this much time.
20848 Defaults to @samp{"2 mins"}.
20851 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
20852 When mbox changes unexpectedly we have to fully read it to find out
20853 what changed. If the mbox is large this can take a long time. Since
20854 the change is usually just a newly appended mail, it'd be faster to
20855 simply read the new mails. If this setting is enabled, Dovecot does
20856 this but still safely fallbacks to re-reading the whole mbox file
20857 whenever something in mbox isn't how it's expected to be. The only real
20858 downside to this setting is that if some other MUA changes message
20859 flags, Dovecot doesn't notice it immediately. Note that a full sync is
20860 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
20861 Defaults to @samp{#t}.
20864 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
20865 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
20866 EXAMINE, EXPUNGE or CHECK commands. If this is set,
20867 @samp{mbox-dirty-syncs} is ignored.
20868 Defaults to @samp{#f}.
20871 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
20872 Delay writing mbox headers until doing a full write sync (EXPUNGE
20873 and CHECK commands and when closing the mailbox). This is especially
20874 useful for POP3 where clients often delete all mails. The downside is
20875 that our changes aren't immediately visible to other MUAs.
20876 Defaults to @samp{#t}.
20879 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
20880 If mbox size is smaller than this (e.g.@: 100k), don't write index
20881 files. If an index file already exists it's still read, just not
20883 Defaults to @samp{0}.
20886 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
20887 Maximum dbox file size until it's rotated.
20888 Defaults to @samp{10000000}.
20891 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
20892 Maximum dbox file age until it's rotated. Typically in days. Day
20893 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
20895 Defaults to @samp{"1d"}.
20898 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
20899 When creating new mdbox files, immediately preallocate their size to
20900 @samp{mdbox-rotate-size}. This setting currently works only in Linux
20901 with some file systems (ext4, xfs).
20902 Defaults to @samp{#f}.
20905 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
20906 sdbox and mdbox support saving mail attachments to external files,
20907 which also allows single instance storage for them. Other backends
20908 don't support this for now.
20910 WARNING: This feature hasn't been tested much yet. Use at your own risk.
20912 Directory root where to store mail attachments. Disabled, if empty.
20913 Defaults to @samp{""}.
20916 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
20917 Attachments smaller than this aren't saved externally. It's also
20918 possible to write a plugin to disable saving specific attachments
20920 Defaults to @samp{128000}.
20923 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
20924 File system backend to use for saving attachments:
20927 No SiS done by Dovecot (but this might help FS's own deduplication)
20929 SiS with immediate byte-by-byte comparison during saving
20930 @item sis-queue posix
20931 SiS with delayed comparison and deduplication.
20933 Defaults to @samp{"sis posix"}.
20936 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
20937 Hash format to use in attachment filenames. You can add any text and
20938 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
20939 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
20940 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
20941 Defaults to @samp{"%@{sha1@}"}.
20944 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
20946 Defaults to @samp{100}.
20949 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
20951 Defaults to @samp{1000}.
20954 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
20955 Default VSZ (virtual memory size) limit for service processes.
20956 This is mainly intended to catch and kill processes that leak memory
20957 before they eat up everything.
20958 Defaults to @samp{256000000}.
20961 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
20962 Login user is internally used by login processes. This is the most
20963 untrusted user in Dovecot system. It shouldn't have access to anything
20965 Defaults to @samp{"dovenull"}.
20968 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
20969 Internal user is used by unprivileged processes. It should be
20970 separate from login user, so that login processes can't disturb other
20972 Defaults to @samp{"dovecot"}.
20975 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
20976 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
20977 Defaults to @samp{"required"}.
20980 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
20981 PEM encoded X.509 SSL/TLS certificate (public key).
20982 Defaults to @samp{"</etc/dovecot/default.pem"}.
20985 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
20986 PEM encoded SSL/TLS private key. The key is opened before
20987 dropping root privileges, so keep the key file unreadable by anyone but
20989 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
20992 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
20993 If key file is password protected, give the password here.
20994 Alternatively give it when starting dovecot with -p parameter. Since
20995 this file is often world-readable, you may want to place this setting
20996 instead to a different.
20997 Defaults to @samp{""}.
21000 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
21001 PEM encoded trusted certificate authority. Set this only if you
21002 intend to use @samp{ssl-verify-client-cert? #t}. The file should
21003 contain the CA certificate(s) followed by the matching
21004 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
21005 Defaults to @samp{""}.
21008 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
21009 Require that CRL check succeeds for client certificates.
21010 Defaults to @samp{#t}.
21013 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
21014 Request client to send a certificate. If you also want to require
21015 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
21016 Defaults to @samp{#f}.
21019 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
21020 Which field from certificate to use for username. commonName and
21021 x500UniqueIdentifier are the usual choices. You'll also need to set
21022 @samp{auth-ssl-username-from-cert? #t}.
21023 Defaults to @samp{"commonName"}.
21026 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
21027 Minimum SSL protocol version to accept.
21028 Defaults to @samp{"TLSv1"}.
21031 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
21032 SSL ciphers to use.
21033 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
21036 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
21037 SSL crypto device to use, for valid values run "openssl engine".
21038 Defaults to @samp{""}.
21041 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
21042 Address to use when sending rejection mails.
21043 %d expands to recipient domain.
21044 Defaults to @samp{"postmaster@@%d"}.
21047 @deftypevr {@code{dovecot-configuration} parameter} string hostname
21048 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
21049 and in LMTP replies. Default is the system's real hostname@@domain.
21050 Defaults to @samp{""}.
21053 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
21054 If user is over quota, return with temporary failure instead of
21056 Defaults to @samp{#f}.
21059 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
21060 Binary to use for sending mails.
21061 Defaults to @samp{"/usr/sbin/sendmail"}.
21064 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
21065 If non-empty, send mails via this SMTP host[:port] instead of
21067 Defaults to @samp{""}.
21070 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
21071 Subject: header to use for rejection mails. You can use the same
21072 variables as for @samp{rejection-reason} below.
21073 Defaults to @samp{"Rejected: %s"}.
21076 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
21077 Human readable error message for rejection mails. You can use
21090 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
21093 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
21094 Delimiter character between local-part and detail in email
21096 Defaults to @samp{"+"}.
21099 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
21100 Header where the original recipient address (SMTP's RCPT TO:
21101 address) is taken from if not available elsewhere. With dovecot-lda -a
21102 parameter overrides this. A commonly used header for this is
21104 Defaults to @samp{""}.
21107 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
21108 Should saving a mail to a nonexistent mailbox automatically create
21110 Defaults to @samp{#f}.
21113 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
21114 Should automatically created mailboxes be also automatically
21116 Defaults to @samp{#f}.
21119 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
21120 Maximum IMAP command line length. Some clients generate very long
21121 command lines with huge mailboxes, so you may need to raise this if you
21122 get "Too long argument" or "IMAP command line too large" errors
21124 Defaults to @samp{64000}.
21127 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
21128 IMAP logout format string:
21131 total number of bytes read from client
21133 total number of bytes sent to client.
21135 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
21136 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@}"}.
21139 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
21140 Override the IMAP CAPABILITY response. If the value begins with '+',
21141 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
21142 Defaults to @samp{""}.
21145 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
21146 How long to wait between "OK Still here" notifications when client
21148 Defaults to @samp{"2 mins"}.
21151 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
21152 ID field names and values to send to clients. Using * as the value
21153 makes Dovecot use the default value. The following fields have default
21154 values currently: name, version, os, os-version, support-url,
21156 Defaults to @samp{""}.
21159 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
21160 ID fields sent by client to log. * means everything.
21161 Defaults to @samp{""}.
21164 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
21165 Workarounds for various client bugs:
21168 @item delay-newmail
21169 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
21170 CHECK commands. Some clients ignore them otherwise, for example OSX
21171 Mail (<v2.1). Outlook Express breaks more badly though, without this it
21172 may show user "Message no longer in server" errors. Note that OE6
21173 still breaks even with this workaround if synchronization is set to
21176 @item tb-extra-mailbox-sep
21177 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
21178 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
21179 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
21181 @item tb-lsub-flags
21182 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
21183 This makes Thunderbird realize they aren't selectable and show them
21184 greyed out, instead of only later giving "not selectable" popup error.
21186 Defaults to @samp{()}.
21189 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
21190 Host allowed in URLAUTH URLs sent by client. "*" allows all.
21191 Defaults to @samp{""}.
21195 Whew! Lots of configuration options. The nice thing about it though is
21196 that Guix has a complete interface to Dovecot's configuration
21197 language. This allows not only a nice way to declare configurations,
21198 but also offers reflective capabilities as well: users can write code to
21199 inspect and transform configurations from within Scheme.
21201 However, it could be that you just want to get a @code{dovecot.conf} up
21202 and running. In that case, you can pass an
21203 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
21204 @code{dovecot-service}. As its name indicates, an opaque configuration
21205 does not have easy reflective capabilities.
21207 Available @code{opaque-dovecot-configuration} fields are:
21209 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
21210 The dovecot package.
21213 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
21214 The contents of the @code{dovecot.conf}, as a string.
21217 For example, if your @code{dovecot.conf} is just the empty string, you
21218 could instantiate a dovecot service like this:
21221 (dovecot-service #:config
21222 (opaque-dovecot-configuration
21226 @subsubheading OpenSMTPD Service
21228 @deffn {Scheme Variable} opensmtpd-service-type
21229 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
21230 service, whose value should be an @code{opensmtpd-configuration} object
21231 as in this example:
21234 (service opensmtpd-service-type
21235 (opensmtpd-configuration
21236 (config-file (local-file "./my-smtpd.conf"))))
21240 @deftp {Data Type} opensmtpd-configuration
21241 Data type representing the configuration of opensmtpd.
21244 @item @code{package} (default: @var{opensmtpd})
21245 Package object of the OpenSMTPD SMTP server.
21247 @item @code{config-file} (default: @code{%default-opensmtpd-file})
21248 File-like object of the OpenSMTPD configuration file to use. By default
21249 it listens on the loopback network interface, and allows for mail from
21250 users and daemons on the local machine, as well as permitting email to
21251 remote servers. Run @command{man smtpd.conf} for more information.
21256 @subsubheading Exim Service
21258 @cindex mail transfer agent (MTA)
21259 @cindex MTA (mail transfer agent)
21262 @deffn {Scheme Variable} exim-service-type
21263 This is the type of the @uref{https://exim.org, Exim} mail transfer
21264 agent (MTA), whose value should be an @code{exim-configuration} object
21265 as in this example:
21268 (service exim-service-type
21269 (exim-configuration
21270 (config-file (local-file "./my-exim.conf"))))
21274 In order to use an @code{exim-service-type} service you must also have a
21275 @code{mail-aliases-service-type} service present in your
21276 @code{operating-system} (even if it has no aliases).
21278 @deftp {Data Type} exim-configuration
21279 Data type representing the configuration of exim.
21282 @item @code{package} (default: @var{exim})
21283 Package object of the Exim server.
21285 @item @code{config-file} (default: @code{#f})
21286 File-like object of the Exim configuration file to use. If its value is
21287 @code{#f} then use the default configuration file from the package
21288 provided in @code{package}. The resulting configuration file is loaded
21289 after setting the @code{exim_user} and @code{exim_group} configuration
21295 @subsubheading Getmail service
21300 @deffn {Scheme Variable} getmail-service-type
21301 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
21302 mail retriever, whose value should be an @code{getmail-configuration}.
21305 Available @code{getmail-configuration} fields are:
21307 @deftypevr {@code{getmail-configuration} parameter} symbol name
21308 A symbol to identify the getmail service.
21310 Defaults to @samp{"unset"}.
21314 @deftypevr {@code{getmail-configuration} parameter} package package
21315 The getmail package to use.
21319 @deftypevr {@code{getmail-configuration} parameter} string user
21320 The user to run getmail as.
21322 Defaults to @samp{"getmail"}.
21326 @deftypevr {@code{getmail-configuration} parameter} string group
21327 The group to run getmail as.
21329 Defaults to @samp{"getmail"}.
21333 @deftypevr {@code{getmail-configuration} parameter} string directory
21334 The getmail directory to use.
21336 Defaults to @samp{"/var/lib/getmail/default"}.
21340 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
21341 The getmail configuration file to use.
21343 Available @code{getmail-configuration-file} fields are:
21345 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
21346 What mail account to retrieve mail from, and how to access that account.
21348 Available @code{getmail-retriever-configuration} fields are:
21350 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
21351 The type of mail retriever to use. Valid values include @samp{passwd}
21354 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
21358 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
21359 Username to login to the mail server with.
21361 Defaults to @samp{unset}.
21365 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
21366 Username to login to the mail server with.
21368 Defaults to @samp{unset}.
21372 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
21373 Port number to connect to.
21375 Defaults to @samp{#f}.
21379 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
21380 Override fields from passwd.
21382 Defaults to @samp{""}.
21386 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
21387 Override fields from passwd.
21389 Defaults to @samp{()}.
21393 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
21394 PEM-formatted key file to use for the TLS negotiation.
21396 Defaults to @samp{""}.
21400 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
21401 PEM-formatted certificate file to use for the TLS negotiation.
21403 Defaults to @samp{""}.
21407 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
21408 CA certificates to use.
21410 Defaults to @samp{""}.
21414 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
21415 Extra retriever parameters.
21417 Defaults to @samp{()}.
21423 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
21424 What to do with retrieved messages.
21426 Available @code{getmail-destination-configuration} fields are:
21428 @deftypevr {@code{getmail-destination-configuration} parameter} string type
21429 The type of mail destination. Valid values include @samp{Maildir},
21430 @samp{Mboxrd} and @samp{MDA_external}.
21432 Defaults to @samp{unset}.
21436 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
21437 The path option for the mail destination. The behaviour depends on the
21440 Defaults to @samp{""}.
21444 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
21445 Extra destination parameters
21447 Defaults to @samp{()}.
21453 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
21456 Available @code{getmail-options-configuration} fields are:
21458 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
21459 If set to @samp{0}, getmail will only print warnings and errors. A
21460 value of @samp{1} means that messages will be printed about retrieving
21461 and deleting messages. If set to @samp{2}, getmail will print messages
21462 about each of it's actions.
21464 Defaults to @samp{1}.
21468 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
21469 If true, getmail will retrieve all available messages. Otherwise it
21470 will only retrieve messages it hasn't seen previously.
21472 Defaults to @samp{#t}.
21476 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
21477 If set to true, messages will be deleted from the server after
21478 retrieving and successfully delivering them. Otherwise, messages will
21479 be left on the server.
21481 Defaults to @samp{#f}.
21485 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
21486 Getmail will delete messages this number of days after seeing them, if
21487 they have been delivered. This means messages will be left on the
21488 server this number of days after delivering them. A value of @samp{0}
21489 disabled this feature.
21491 Defaults to @samp{0}.
21495 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
21496 Delete messages larger than this of bytes after retrieving them, even if
21497 the delete and delete-after options are disabled. A value of @samp{0}
21498 disables this feature.
21500 Defaults to @samp{0}.
21504 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
21505 Retrieve messages totalling up to this number of bytes before closing
21506 the session with the server. A value of @samp{0} disables this feature.
21508 Defaults to @samp{0}.
21512 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
21513 Don't retrieve messages larger than this number of bytes. A value of
21514 @samp{0} disables this feature.
21516 Defaults to @samp{0}.
21520 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
21521 If true, getmail will add a Delivered-To header to messages.
21523 Defaults to @samp{#t}.
21527 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
21528 If set, getmail adds a Received header to the messages.
21530 Defaults to @samp{#t}.
21534 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
21535 Getmail will record a log of its actions to the named file. A value of
21536 @samp{""} disables this feature.
21538 Defaults to @samp{""}.
21542 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
21543 If true, getmail will record a log of its actions using the system
21546 Defaults to @samp{#f}.
21550 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
21551 If true, getmail will log information about messages not retrieved and
21552 the reason for not retrieving them, as well as starting and ending
21555 Defaults to @samp{#f}.
21559 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
21560 Extra options to include.
21562 Defaults to @samp{()}.
21570 @deftypevr {@code{getmail-configuration} parameter} list idle
21571 A list of mailboxes that getmail should wait on the server for new mail
21572 notifications. This depends on the server supporting the IDLE
21575 Defaults to @samp{()}.
21579 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
21580 Environment variables to set for getmail.
21582 Defaults to @samp{()}.
21586 @subsubheading Mail Aliases Service
21588 @cindex email aliases
21589 @cindex aliases, for email addresses
21591 @deffn {Scheme Variable} mail-aliases-service-type
21592 This is the type of the service which provides @code{/etc/aliases},
21593 specifying how to deliver mail to users on this system.
21596 (service mail-aliases-service-type
21597 '(("postmaster" "bob")
21598 ("bob" "bob@@example.com" "bob@@example2.com")))
21602 The configuration for a @code{mail-aliases-service-type} service is an
21603 association list denoting how to deliver mail that comes to this
21604 system. Each entry is of the form @code{(alias addresses ...)}, with
21605 @code{alias} specifying the local alias and @code{addresses} specifying
21606 where to deliver this user's mail.
21608 The aliases aren't required to exist as users on the local system. In
21609 the above example, there doesn't need to be a @code{postmaster} entry in
21610 the @code{operating-system}'s @code{user-accounts} in order to deliver
21611 the @code{postmaster} mail to @code{bob} (which subsequently would
21612 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
21614 @subsubheading GNU Mailutils IMAP4 Daemon
21615 @cindex GNU Mailutils IMAP4 Daemon
21617 @deffn {Scheme Variable} imap4d-service-type
21618 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
21619 mailutils, GNU Mailutils Manual}), whose value should be an
21620 @code{imap4d-configuration} object as in this example:
21623 (service imap4d-service-type
21624 (imap4d-configuration
21625 (config-file (local-file "imap4d.conf"))))
21629 @deftp {Data Type} imap4d-configuration
21630 Data type representing the configuration of @command{imap4d}.
21633 @item @code{package} (default: @code{mailutils})
21634 The package that provides @command{imap4d}.
21636 @item @code{config-file} (default: @code{%default-imap4d-config-file})
21637 File-like object of the configuration file to use, by default it will listen
21638 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
21639 Mailutils Manual}, for details.
21644 @subsubheading Radicale Service
21648 @deffn {Scheme Variable} radicale-service-type
21649 This is the type of the @uref{https://radicale.org, Radicale} CalDAV/CardDAV
21650 server whose value should be a @code{radicale-configuration}.
21653 @deftp {Data Type} radicale-configuration
21654 Data type representing the configuration of @command{radicale}.
21657 @item @code{package} (default: @code{radicale})
21658 The package that provides @command{radicale}.
21660 @item @code{config-file} (default: @code{%default-radicale-config-file})
21661 File-like object of the configuration file to use, by default it will listen
21662 on TCP port 5232 of @code{localhost} and use the @code{htpasswd} file at
21663 @file{/var/lib/radicale/users} with no (@code{plain}) encryption.
21668 @node Messaging Services
21669 @subsection Messaging Services
21674 The @code{(gnu services messaging)} module provides Guix service
21675 definitions for messaging services. Currently it provides the following
21678 @subsubheading Prosody Service
21680 @deffn {Scheme Variable} prosody-service-type
21681 This is the type for the @uref{https://prosody.im, Prosody XMPP
21682 communication server}. Its value must be a @code{prosody-configuration}
21683 record as in this example:
21686 (service prosody-service-type
21687 (prosody-configuration
21688 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
21691 (int-component-configuration
21692 (hostname "conference.example.net")
21694 (mod-muc (mod-muc-configuration)))))
21697 (virtualhost-configuration
21698 (domain "example.net"))))))
21701 See below for details about @code{prosody-configuration}.
21705 By default, Prosody does not need much configuration. Only one
21706 @code{virtualhosts} field is needed: it specifies the domain you wish
21709 You can perform various sanity checks on the generated configuration
21710 with the @code{prosodyctl check} command.
21712 Prosodyctl will also help you to import certificates from the
21713 @code{letsencrypt} directory so that the @code{prosody} user can access
21714 them. See @url{https://prosody.im/doc/letsencrypt}.
21717 prosodyctl --root cert import /etc/letsencrypt/live
21720 The available configuration parameters follow. Each parameter
21721 definition is preceded by its type; for example, @samp{string-list foo}
21722 indicates that the @code{foo} parameter should be specified as a list of
21723 strings. Types starting with @code{maybe-} denote parameters that won't
21724 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
21726 There is also a way to specify the configuration as a string, if you
21727 have an old @code{prosody.cfg.lua} file that you want to port over from
21728 some other system; see the end for more details.
21730 The @code{file-object} type designates either a file-like object
21731 (@pxref{G-Expressions, file-like objects}) or a file name.
21733 @c The following documentation was initially generated by
21734 @c (generate-documentation) in (gnu services messaging). Manually maintained
21735 @c documentation is better, so we shouldn't hesitate to edit below as
21736 @c needed. However if the change you want to make to this documentation
21737 @c can be done in an automated way, it's probably easier to change
21738 @c (generate-documentation) than to make it below and have to deal with
21739 @c the churn as Prosody updates.
21741 Available @code{prosody-configuration} fields are:
21743 @deftypevr {@code{prosody-configuration} parameter} package prosody
21744 The Prosody package.
21747 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
21748 Location of the Prosody data storage directory. See
21749 @url{https://prosody.im/doc/configure}.
21750 Defaults to @samp{"/var/lib/prosody"}.
21753 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
21754 Additional plugin directories. They are searched in all the specified
21755 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
21756 Defaults to @samp{()}.
21759 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
21760 Every virtual host and component needs a certificate so that clients and
21761 servers can securely verify its identity. Prosody will automatically load
21762 certificates/keys from the directory specified here.
21763 Defaults to @samp{"/etc/prosody/certs"}.
21766 @deftypevr {@code{prosody-configuration} parameter} string-list admins
21767 This is a list of accounts that are admins for the server. Note that you
21768 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
21769 @url{https://prosody.im/doc/creating_accounts}.
21770 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
21771 Defaults to @samp{()}.
21774 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
21775 Enable use of libevent for better performance under high load. See
21776 @url{https://prosody.im/doc/libevent}.
21777 Defaults to @samp{#f}.
21780 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
21781 This is the list of modules Prosody will load on startup. It looks for
21782 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
21783 Documentation on modules can be found at:
21784 @url{https://prosody.im/doc/modules}.
21785 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
21788 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
21789 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
21790 should you want to disable them then add them to this list.
21791 Defaults to @samp{()}.
21794 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
21795 Path to a text file where the shared groups are defined. If this path is
21796 empty then @samp{mod_groups} does nothing. See
21797 @url{https://prosody.im/doc/modules/mod_groups}.
21798 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
21801 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
21802 Disable account creation by default, for security. See
21803 @url{https://prosody.im/doc/creating_accounts}.
21804 Defaults to @samp{#f}.
21807 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
21808 These are the SSL/TLS-related settings. Most of them are disabled so to
21809 use Prosody's defaults. If you do not completely understand these options, do
21810 not add them to your config, it is easy to lower the security of your server
21811 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
21813 Available @code{ssl-configuration} fields are:
21815 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
21816 This determines what handshake to use.
21819 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
21820 Path to your private key file.
21823 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
21824 Path to your certificate file.
21827 @deftypevr {@code{ssl-configuration} parameter} file-object capath
21828 Path to directory containing root certificates that you wish Prosody to
21829 trust when verifying the certificates of remote servers.
21830 Defaults to @samp{"/etc/ssl/certs"}.
21833 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
21834 Path to a file containing root certificates that you wish Prosody to trust.
21835 Similar to @code{capath} but with all certificates concatenated together.
21838 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
21839 A list of verification options (these mostly map to OpenSSL's
21840 @code{set_verify()} flags).
21843 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
21844 A list of general options relating to SSL/TLS@. These map to OpenSSL's
21845 @code{set_options()}. For a full list of options available in LuaSec, see the
21849 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
21850 How long a chain of certificate authorities to check when looking for a
21851 trusted root certificate.
21854 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
21855 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
21856 clients, and in what order.
21859 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
21860 A path to a file containing parameters for Diffie-Hellman key exchange. You
21861 can create such a file with:
21862 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
21865 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
21866 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
21867 @samp{"secp384r1"}.
21870 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
21871 A list of ``extra'' verification options.
21874 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
21875 Password for encrypted private keys.
21880 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
21881 Whether to force all client-to-server connections to be encrypted or not.
21882 See @url{https://prosody.im/doc/modules/mod_tls}.
21883 Defaults to @samp{#f}.
21886 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
21887 Set of mechanisms that will never be offered. See
21888 @url{https://prosody.im/doc/modules/mod_saslauth}.
21889 Defaults to @samp{("DIGEST-MD5")}.
21892 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
21893 Whether to force all server-to-server connections to be encrypted or not.
21894 See @url{https://prosody.im/doc/modules/mod_tls}.
21895 Defaults to @samp{#f}.
21898 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
21899 Whether to require encryption and certificate authentication. This
21900 provides ideal security, but requires servers you communicate with to support
21901 encryption AND present valid, trusted certificates. See
21902 @url{https://prosody.im/doc/s2s#security}.
21903 Defaults to @samp{#f}.
21906 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
21907 Many servers don't support encryption or have invalid or self-signed
21908 certificates. You can list domains here that will not be required to
21909 authenticate using certificates. They will be authenticated using DNS@. See
21910 @url{https://prosody.im/doc/s2s#security}.
21911 Defaults to @samp{()}.
21914 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
21915 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
21916 valid certificates for some domains by specifying a list here. See
21917 @url{https://prosody.im/doc/s2s#security}.
21918 Defaults to @samp{()}.
21921 @deftypevr {@code{prosody-configuration} parameter} string authentication
21922 Select the authentication backend to use. The default provider stores
21923 passwords in plaintext and uses Prosody's configured data storage to store the
21924 authentication data. If you do not trust your server please see
21925 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
21926 about using the hashed backend. See also
21927 @url{https://prosody.im/doc/authentication}
21928 Defaults to @samp{"internal_plain"}.
21931 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
21932 Set logging options. Advanced logging configuration is not yet supported
21933 by the Prosody service. See @url{https://prosody.im/doc/logging}.
21934 Defaults to @samp{"*syslog"}.
21937 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
21938 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
21939 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
21942 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
21943 Maximum allowed size of the HTTP body (in bytes).
21946 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
21947 Some modules expose their own URL in various ways. This URL is built
21948 from the protocol, host and port used. If Prosody sits behind a proxy, the
21949 public URL will be @code{http-external-url} instead. See
21950 @url{https://prosody.im/doc/http#external_url}.
21953 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
21954 A host in Prosody is a domain on which user accounts can be created. For
21955 example if you want your users to have addresses like
21956 @samp{"john.smith@@example.com"} then you need to add a host
21957 @samp{"example.com"}. All options in this list will apply only to this host.
21959 Note: the name @emph{virtual} host is used in configuration to avoid confusion with
21960 the actual physical host that Prosody is installed on. A single Prosody
21961 instance can serve many domains, each one defined as a VirtualHost entry in
21962 Prosody's configuration. Conversely a server that hosts a single domain would
21963 have just one VirtualHost entry.
21965 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
21967 Available @code{virtualhost-configuration} fields are:
21969 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:
21970 @deftypevr {@code{virtualhost-configuration} parameter} string domain
21971 Domain you wish Prosody to serve.
21976 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
21977 Components are extra services on a server which are available to clients,
21978 usually on a subdomain of the main server (such as
21979 @samp{"mycomponent.example.com"}). Example components might be chatroom
21980 servers, user directories, or gateways to other protocols.
21982 Internal components are implemented with Prosody-specific plugins. To add an
21983 internal component, you simply fill the hostname field, and the plugin you wish
21984 to use for the component.
21986 See @url{https://prosody.im/doc/components}.
21987 Defaults to @samp{()}.
21989 Available @code{int-component-configuration} fields are:
21991 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:
21992 @deftypevr {@code{int-component-configuration} parameter} string hostname
21993 Hostname of the component.
21996 @deftypevr {@code{int-component-configuration} parameter} string plugin
21997 Plugin you wish to use for the component.
22000 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
22001 Multi-user chat (MUC) is Prosody's module for allowing you to create
22002 hosted chatrooms/conferences for XMPP users.
22004 General information on setting up and using multi-user chatrooms can be found
22005 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
22006 which you should read if you are new to XMPP chatrooms.
22008 See also @url{https://prosody.im/doc/modules/mod_muc}.
22010 Available @code{mod-muc-configuration} fields are:
22012 @deftypevr {@code{mod-muc-configuration} parameter} string name
22013 The name to return in service discovery responses.
22014 Defaults to @samp{"Prosody Chatrooms"}.
22017 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
22018 If @samp{#t}, this will only allow admins to create new chatrooms.
22019 Otherwise anyone can create a room. The value @samp{"local"} restricts room
22020 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
22021 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
22022 restricts to service administrators only.
22023 Defaults to @samp{#f}.
22026 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
22027 Maximum number of history messages that will be sent to the member that has
22028 just joined the room.
22029 Defaults to @samp{20}.
22036 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
22037 External components use XEP-0114, which most standalone components
22038 support. To add an external component, you simply fill the hostname field. See
22039 @url{https://prosody.im/doc/components}.
22040 Defaults to @samp{()}.
22042 Available @code{ext-component-configuration} fields are:
22044 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:
22045 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
22046 Password which the component will use to log in.
22049 @deftypevr {@code{ext-component-configuration} parameter} string hostname
22050 Hostname of the component.
22055 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
22056 Port(s) Prosody listens on for component connections.
22057 Defaults to @samp{(5347)}.
22060 @deftypevr {@code{prosody-configuration} parameter} string component-interface
22061 Interface Prosody listens on for component connections.
22062 Defaults to @samp{"127.0.0.1"}.
22065 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
22066 Raw content that will be added to the configuration file.
22069 It could be that you just want to get a @code{prosody.cfg.lua}
22070 up and running. In that case, you can pass an
22071 @code{opaque-prosody-configuration} record as the value of
22072 @code{prosody-service-type}. As its name indicates, an opaque configuration
22073 does not have easy reflective capabilities.
22074 Available @code{opaque-prosody-configuration} fields are:
22076 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
22077 The prosody package.
22080 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
22081 The contents of the @code{prosody.cfg.lua} to use.
22084 For example, if your @code{prosody.cfg.lua} is just the empty
22085 string, you could instantiate a prosody service like this:
22088 (service prosody-service-type
22089 (opaque-prosody-configuration
22090 (prosody.cfg.lua "")))
22093 @c end of Prosody auto-generated documentation
22095 @subsubheading BitlBee Service
22097 @cindex IRC (Internet Relay Chat)
22098 @cindex IRC gateway
22099 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
22100 interface to a variety of messaging protocols such as XMPP.
22102 @defvr {Scheme Variable} bitlbee-service-type
22103 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
22104 gateway daemon. Its value is a @code{bitlbee-configuration} (see
22107 To have BitlBee listen on port 6667 on localhost, add this line to your
22111 (service bitlbee-service-type)
22115 @deftp {Data Type} bitlbee-configuration
22116 This is the configuration for BitlBee, with the following fields:
22119 @item @code{interface} (default: @code{"127.0.0.1"})
22120 @itemx @code{port} (default: @code{6667})
22121 Listen on the network interface corresponding to the IP address
22122 specified in @var{interface}, on @var{port}.
22124 When @var{interface} is @code{127.0.0.1}, only local clients can
22125 connect; when it is @code{0.0.0.0}, connections can come from any
22126 networking interface.
22128 @item @code{bitlbee} (default: @code{bitlbee})
22129 The BitlBee package to use.
22131 @item @code{plugins} (default: @code{'()})
22132 List of plugin packages to use---e.g., @code{bitlbee-discord}.
22134 @item @code{extra-settings} (default: @code{""})
22135 Configuration snippet added as-is to the BitlBee configuration file.
22139 @subsubheading Quassel Service
22141 @cindex IRC (Internet Relay Chat)
22142 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
22143 meaning that one or more clients can attach to and detach from the
22146 @defvr {Scheme Variable} quassel-service-type
22147 This is the service type for the @url{https://quassel-irc.org/,Quassel}
22148 IRC backend daemon. Its value is a @code{quassel-configuration}
22152 @deftp {Data Type} quassel-configuration
22153 This is the configuration for Quassel, with the following fields:
22156 @item @code{quassel} (default: @code{quassel})
22157 The Quassel package to use.
22159 @item @code{interface} (default: @code{"::,0.0.0.0"})
22160 @item @code{port} (default: @code{4242})
22161 Listen on the network interface(s) corresponding to the IPv4 or IPv6
22162 interfaces specified in the comma delimited @var{interface}, on
22165 @item @code{loglevel} (default: @code{"Info"})
22166 The level of logging desired. Accepted values are Debug, Info, Warning
22171 @node Telephony Services
22172 @subsection Telephony Services
22174 @cindex Murmur (VoIP server)
22175 @cindex VoIP server
22176 This section describes how to set up and run a Murmur server. Murmur is
22177 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
22180 @deftp {Data Type} murmur-configuration
22181 The service type for the Murmur server. An example configuration can
22185 (service murmur-service-type
22186 (murmur-configuration
22188 "Welcome to this Mumble server running on Guix!")
22189 (cert-required? #t) ;disallow text password logins
22190 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
22191 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
22194 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
22195 password with the command that is printed during the activation phase.
22197 It is recommended to register a normal Mumble user account
22198 and grant it admin or moderator rights.
22199 You can use the @code{mumble} client to
22200 login as new normal user, register yourself, and log out.
22201 For the next step login with the name @code{SuperUser} use
22202 the @code{SuperUser} password that you set previously,
22203 and grant your newly registered mumble user administrator or moderator
22204 rights and create some channels.
22206 Available @code{murmur-configuration} fields are:
22209 @item @code{package} (default: @code{mumble})
22210 Package that contains @code{bin/murmurd}.
22212 @item @code{user} (default: @code{"murmur"})
22213 User who will run the Murmur server.
22215 @item @code{group} (default: @code{"murmur"})
22216 Group of the user who will run the murmur server.
22218 @item @code{port} (default: @code{64738})
22219 Port on which the server will listen.
22221 @item @code{welcome-text} (default: @code{""})
22222 Welcome text sent to clients when they connect.
22224 @item @code{server-password} (default: @code{""})
22225 Password the clients have to enter in order to connect.
22227 @item @code{max-users} (default: @code{100})
22228 Maximum of users that can be connected to the server at once.
22230 @item @code{max-user-bandwidth} (default: @code{#f})
22231 Maximum voice traffic a user can send per second.
22233 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
22234 File name of the sqlite database.
22235 The service's user will become the owner of the directory.
22237 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
22238 File name of the log file.
22239 The service's user will become the owner of the directory.
22241 @item @code{autoban-attempts} (default: @code{10})
22242 Maximum number of logins a user can make in @code{autoban-timeframe}
22243 without getting auto banned for @code{autoban-time}.
22245 @item @code{autoban-timeframe} (default: @code{120})
22246 Timeframe for autoban in seconds.
22248 @item @code{autoban-time} (default: @code{300})
22249 Amount of time in seconds for which a client gets banned
22250 when violating the autoban limits.
22252 @item @code{opus-threshold} (default: @code{100})
22253 Percentage of clients that need to support opus
22254 before switching over to opus audio codec.
22256 @item @code{channel-nesting-limit} (default: @code{10})
22257 How deep channels can be nested at maximum.
22259 @item @code{channelname-regex} (default: @code{#f})
22260 A string in form of a Qt regular expression that channel names must conform to.
22262 @item @code{username-regex} (default: @code{#f})
22263 A string in form of a Qt regular expression that user names must conform to.
22265 @item @code{text-message-length} (default: @code{5000})
22266 Maximum size in bytes that a user can send in one text chat message.
22268 @item @code{image-message-length} (default: @code{(* 128 1024)})
22269 Maximum size in bytes that a user can send in one image message.
22271 @item @code{cert-required?} (default: @code{#f})
22272 If it is set to @code{#t} clients that use weak password authentication
22273 will not be accepted. Users must have completed the certificate wizard to join.
22275 @item @code{remember-channel?} (default: @code{#f})
22276 Should murmur remember the last channel each user was in when they disconnected
22277 and put them into the remembered channel when they rejoin.
22279 @item @code{allow-html?} (default: @code{#f})
22280 Should html be allowed in text messages, user comments, and channel descriptions.
22282 @item @code{allow-ping?} (default: @code{#f})
22283 Setting to true exposes the current user count, the maximum user count, and
22284 the server's maximum bandwidth per client to unauthenticated users. In the
22285 Mumble client, this information is shown in the Connect dialog.
22287 Disabling this setting will prevent public listing of the server.
22289 @item @code{bonjour?} (default: @code{#f})
22290 Should the server advertise itself in the local network through the bonjour protocol.
22292 @item @code{send-version?} (default: @code{#f})
22293 Should the murmur server version be exposed in ping requests.
22295 @item @code{log-days} (default: @code{31})
22296 Murmur also stores logs in the database, which are accessible via RPC.
22297 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
22298 or -1 to disable logging to the database.
22300 @item @code{obfuscate-ips?} (default: @code{#t})
22301 Should logged ips be obfuscated to protect the privacy of users.
22303 @item @code{ssl-cert} (default: @code{#f})
22304 File name of the SSL/TLS certificate used for encrypted connections.
22307 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
22309 @item @code{ssl-key} (default: @code{#f})
22310 Filepath to the ssl private key used for encrypted connections.
22312 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
22315 @item @code{ssl-dh-params} (default: @code{#f})
22316 File name of a PEM-encoded file with Diffie-Hellman parameters
22317 for the SSL/TLS encryption. Alternatively you set it to
22318 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
22319 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
22321 @item @code{ssl-ciphers} (default: @code{#f})
22322 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
22325 This option is specified using
22326 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
22327 OpenSSL cipher list notation}.
22329 It is recommended that you try your cipher string using 'openssl ciphers <string>'
22330 before setting it here, to get a feel for which cipher suites you will get.
22331 After setting this option, it is recommend that you inspect your Murmur log
22332 to ensure that Murmur is using the cipher suites that you expected it to.
22334 Note: Changing this option may impact the backwards compatibility of your
22335 Murmur server, and can remove the ability for older Mumble clients to be able
22338 @item @code{public-registration} (default: @code{#f})
22339 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
22341 You can optionally register your server in the public server list that the
22342 @code{mumble} client shows on startup.
22343 You cannot register your server if you have set a @code{server-password},
22344 or set @code{allow-ping} to @code{#f}.
22346 It might take a few hours until it shows up in the public list.
22348 @item @code{file} (default: @code{#f})
22349 Optional alternative override for this configuration.
22353 @deftp {Data Type} murmur-public-registration-configuration
22354 Configuration for public registration of a murmur service.
22358 This is a display name for your server. Not to be confused with the hostname.
22360 @item @code{password}
22361 A password to identify your registration.
22362 Subsequent updates will need the same password. Don't lose your password.
22365 This should be a @code{http://} or @code{https://} link to your web
22368 @item @code{hostname} (default: @code{#f})
22369 By default your server will be listed by its IP address.
22370 If it is set your server will be linked by this host name instead.
22376 @node File-Sharing Services
22377 @subsection File-Sharing Services
22379 The @code{(gnu services file-sharing)} module provides services that
22380 assist with transferring files over peer-to-peer file-sharing networks.
22382 @subsubheading Transmission Daemon Service
22384 @uref{https://transmissionbt.com/, Transmission} is a flexible
22385 BitTorrent client that offers a variety of graphical and command-line
22386 interfaces. A @code{transmission-daemon-service-type} service provides
22387 Transmission's headless variant, @command{transmission-daemon}, as a
22388 system service, allowing users to share files via BitTorrent even when
22389 they are not logged in.
22391 @deffn {Scheme Variable} transmission-daemon-service-type
22392 The service type for the Transmission Daemon BitTorrent client. Its
22393 value must be a @code{transmission-daemon-configuration} object as in
22397 (service transmission-daemon-service-type
22398 (transmission-daemon-configuration
22399 ;; Restrict access to the RPC ("control") interface
22400 (rpc-authentication-required? #t)
22401 (rpc-username "transmission")
22403 (transmission-password-hash
22404 "transmission" ; desired password
22405 "uKd1uMs9")) ; arbitrary salt value
22407 ;; Accept requests from this and other hosts on the
22409 (rpc-whitelist-enabled? #t)
22410 (rpc-whitelist '("::1" "127.0.0.1" "192.168.0.*"))
22412 ;; Limit bandwidth use during work hours
22413 (alt-speed-down (* 1024 2)) ; 2 MB/s
22414 (alt-speed-up 512) ; 512 kB/s
22416 (alt-speed-time-enabled? #t)
22417 (alt-speed-time-day 'weekdays)
22418 (alt-speed-time-begin
22419 (+ (* 60 8) 30)) ; 8:30 am
22420 (alt-speed-time-end
22421 (+ (* 60 (+ 12 5)) 30)))) ; 5:30 pm
22425 Once the service is started, users can interact with the daemon through
22426 its Web interface (at @code{http://localhost:9091/}) or by using the
22427 @command{transmission-remote} command-line tool, available in the
22428 @code{transmission} package. (Emacs users may want to also consider the
22429 @code{emacs-transmission} package.) Both communicate with the daemon
22430 through its remote procedure call (RPC) interface, which by default is
22431 available to all users on the system; you may wish to change this by
22432 assigning values to the @code{rpc-authentication-required?},
22433 @code{rpc-username} and @code{rpc-password} settings, as shown in the
22434 example above and documented further below.
22436 The value for @code{rpc-password} must be a password hash of the type
22437 generated and used by Transmission clients. This can be copied verbatim
22438 from an existing @file{settings.json} file, if another Transmission
22439 client is already being used. Otherwise, the
22440 @code{transmission-password-hash} and @code{transmission-random-salt}
22441 procedures provided by this module can be used to obtain a suitable hash
22444 @deffn {Scheme Procedure} transmission-password-hash @var{password} @var{salt}
22445 Returns a string containing the result of hashing @var{password}
22446 together with @var{salt}, in the format recognized by Transmission
22447 clients for their @code{rpc-password} configuration setting.
22449 @var{salt} must be an eight-character string. The
22450 @code{transmission-random-salt} procedure can be used to generate a
22451 suitable salt value at random.
22454 @deffn {Scheme Procedure} transmission-random-salt
22455 Returns a string containing a random, eight-character salt value of the
22456 type generated and used by Transmission clients, suitable for passing to
22457 the @code{transmission-password-hash} procedure.
22460 These procedures are accessible from within a Guile REPL started with
22461 the @command{guix repl} command (@pxref{Invoking guix repl}). This is
22462 useful for obtaining a random salt value to provide as the second
22463 parameter to `transmission-password-hash`, as in this example session:
22467 scheme@@(guix-user)> ,use (gnu services file-sharing)
22468 scheme@@(guix-user)> (transmission-random-salt)
22472 Alternatively, a complete password hash can generated in a single step:
22475 scheme@@(guix-user)> (transmission-password-hash "transmission"
22476 (transmission-random-salt))
22477 $2 = "@{c8bbc6d1740cd8dc819a6e25563b67812c1c19c9VtFPfdsX"
22480 The resulting string can be used as-is for the value of
22481 @code{rpc-password}, allowing the password to be kept hidden even in the
22482 operating-system configuration.
22484 Torrent files downloaded by the daemon are directly accessible only to
22485 users in the ``transmission'' user group, who receive read-only access
22486 to the directory specified by the @code{download-dir} configuration
22487 setting (and also the directory specified by @code{incomplete-dir}, if
22488 @code{incomplete-dir-enabled?} is @code{#t}). Downloaded files can be
22489 moved to another directory or deleted altogether using
22490 @command{transmission-remote} with its @code{--move} and
22491 @code{--remove-and-delete} options.
22493 If the @code{watch-dir-enabled?} setting is set to @code{#t}, users in
22494 the ``transmission'' group are able also to place @file{.torrent} files
22495 in the directory specified by @code{watch-dir} to have the corresponding
22496 torrents added by the daemon. (The @code{trash-original-torrent-files?}
22497 setting controls whether the daemon deletes these files after processing
22500 Some of the daemon's configuration settings can be changed temporarily
22501 by @command{transmission-remote} and similar tools. To undo these
22502 changes, use the service's @code{reload} action to have the daemon
22503 reload its settings from disk:
22506 # herd reload transmission-daemon
22509 The full set of available configuration settings is defined by the
22510 @code{transmission-daemon-configuration} data type.
22512 @deftp {Data Type} transmission-daemon-configuration
22513 The data type representing configuration settings for Transmission
22514 Daemon. These correspond directly to the settings recognized by
22515 Transmission clients in their @file{settings.json} file.
22518 @c The following documentation was initially generated by
22519 @c (generate-transmission-daemon-documentation) in (gnu services
22520 @c file-sharing). Manually maintained documentation is better, so we
22521 @c shouldn't hesitate to edit below as needed. However if the change
22522 @c you want to make to this documentation can be done in an automated
22523 @c way, it's probably easier to change (generate-documentation) than to
22524 @c make it below and have to deal with the churn as Transmission Daemon
22527 @c %start of fragment
22529 Available @code{transmission-daemon-configuration} fields are:
22531 @deftypevr {@code{transmission-daemon-configuration} parameter} package transmission
22532 The Transmission package to use.
22536 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer stop-wait-period
22537 The period, in seconds, to wait when stopping the service for
22538 @command{transmission-daemon} to exit before killing its process. This
22539 allows the daemon time to complete its housekeeping and send a final
22540 update to trackers as it shuts down. On slow hosts, or hosts with a
22541 slow network connection, this value may need to be increased.
22543 Defaults to @samp{10}.
22547 @deftypevr {@code{transmission-daemon-configuration} parameter} string download-dir
22548 The directory to which torrent files are downloaded.
22550 Defaults to @samp{"/var/lib/transmission-daemon/downloads"}.
22554 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean incomplete-dir-enabled?
22555 If @code{#t}, files will be held in @code{incomplete-dir} while their
22556 torrent is being downloaded, then moved to @code{download-dir} once the
22557 torrent is complete. Otherwise, files for all torrents (including those
22558 still being downloaded) will be placed in @code{download-dir}.
22560 Defaults to @samp{#f}.
22564 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string incomplete-dir
22565 The directory in which files from incompletely downloaded torrents will
22566 be held when @code{incomplete-dir-enabled?} is @code{#t}.
22568 Defaults to @samp{disabled}.
22572 @deftypevr {@code{transmission-daemon-configuration} parameter} umask umask
22573 The file mode creation mask used for downloaded files. (See the
22574 @command{umask} man page for more information.)
22576 Defaults to @samp{18}.
22580 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rename-partial-files?
22581 When @code{#t}, ``.part'' is appended to the name of partially
22584 Defaults to @samp{#t}.
22588 @deftypevr {@code{transmission-daemon-configuration} parameter} preallocation-mode preallocation
22589 The mode by which space should be preallocated for downloaded files, one
22590 of @code{none}, @code{fast} (or @code{sparse}) and @code{full}.
22591 Specifying @code{full} will minimize disk fragmentation at a cost to
22592 file-creation speed.
22594 Defaults to @samp{fast}.
22598 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean watch-dir-enabled?
22599 If @code{#t}, the directory specified by @code{watch-dir} will be
22600 watched for new @file{.torrent} files and the torrents they describe
22601 added automatically (and the original files removed, if
22602 @code{trash-original-torrent-files?} is @code{#t}).
22604 Defaults to @samp{#f}.
22608 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string watch-dir
22609 The directory to be watched for @file{.torrent} files indicating new
22610 torrents to be added, when @code{watch-dir-enabled} is @code{#t}.
22612 Defaults to @samp{disabled}.
22616 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean trash-original-torrent-files?
22617 When @code{#t}, @file{.torrent} files will be deleted from the watch
22618 directory once their torrent has been added (see
22619 @code{watch-directory-enabled?}).
22621 Defaults to @samp{#f}.
22625 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-down-enabled?
22626 When @code{#t}, the daemon's download speed will be limited to the rate
22627 specified by @code{speed-limit-down}.
22629 Defaults to @samp{#f}.
22633 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-down
22634 The default global-maximum download speed, in kilobytes per second.
22636 Defaults to @samp{100}.
22640 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-up-enabled?
22641 When @code{#t}, the daemon's upload speed will be limited to the rate
22642 specified by @code{speed-limit-up}.
22644 Defaults to @samp{#f}.
22648 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-up
22649 The default global-maximum upload speed, in kilobytes per second.
22651 Defaults to @samp{100}.
22655 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-enabled?
22656 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
22657 @code{alt-speed-up} are used (in place of @code{speed-limit-down} and
22658 @code{speed-limit-up}, if they are enabled) to constrain the daemon's
22659 bandwidth usage. This can be scheduled to occur automatically at
22660 certain times during the week; see @code{alt-speed-time-enabled?}.
22662 Defaults to @samp{#f}.
22666 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-down
22667 The alternate global-maximum download speed, in kilobytes per second.
22669 Defaults to @samp{50}.
22673 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-up
22674 The alternate global-maximum upload speed, in kilobytes per second.
22676 Defaults to @samp{50}.
22680 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-time-enabled?
22681 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
22682 @code{alt-speed-up} will be enabled automatically during the periods
22683 specified by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
22684 @code{alt-time-speed-end}.
22686 Defaults to @samp{#f}.
22690 @deftypevr {@code{transmission-daemon-configuration} parameter} day-list alt-speed-time-day
22691 The days of the week on which the alternate-speed schedule should be
22692 used, specified either as a list of days (@code{sunday}, @code{monday},
22693 and so on) or using one of the symbols @code{weekdays}, @code{weekends}
22696 Defaults to @samp{all}.
22700 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-begin
22701 The time of day at which to enable the alternate speed limits, expressed
22702 as a number of minutes since midnight.
22704 Defaults to @samp{540}.
22708 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-end
22709 The time of day at which to disable the alternate speed limits,
22710 expressed as a number of minutes since midnight.
22712 Defaults to @samp{1020}.
22716 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv4
22717 The IP address at which to listen for peer connections, or ``0.0.0.0''
22718 to listen at all available IP addresses.
22720 Defaults to @samp{"0.0.0.0"}.
22724 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv6
22725 The IPv6 address at which to listen for peer connections, or ``::'' to
22726 listen at all available IPv6 addresses.
22728 Defaults to @samp{"::"}.
22732 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean peer-port-random-on-start?
22733 If @code{#t}, when the daemon starts it will select a port at random on
22734 which to listen for peer connections, from the range specified
22735 (inclusively) by @code{peer-port-random-low} and
22736 @code{peer-port-random-high}. Otherwise, it listens on the port
22737 specified by @code{peer-port}.
22739 Defaults to @samp{#f}.
22743 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-low
22744 The lowest selectable port number when @code{peer-port-random-on-start?}
22747 Defaults to @samp{49152}.
22751 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-high
22752 The highest selectable port number when @code{peer-port-random-on-start}
22755 Defaults to @samp{65535}.
22759 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port
22760 The port on which to listen for peer connections when
22761 @code{peer-port-random-on-start?} is @code{#f}.
22763 Defaults to @samp{51413}.
22767 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean port-forwarding-enabled?
22768 If @code{#t}, the daemon will attempt to configure port-forwarding on an
22769 upstream gateway automatically using @acronym{UPnP} and
22772 Defaults to @samp{#t}.
22776 @deftypevr {@code{transmission-daemon-configuration} parameter} encryption-mode encryption
22777 The encryption preference for peer connections, one of
22778 @code{prefer-unencrypted-connections},
22779 @code{prefer-encrypted-connections} or
22780 @code{require-encrypted-connections}.
22782 Defaults to @samp{prefer-encrypted-connections}.
22786 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string peer-congestion-algorithm
22787 The TCP congestion-control algorithm to use for peer connections,
22788 specified using a string recognized by the operating system in calls to
22789 @code{setsockopt} (or set to @code{disabled}, in which case the
22790 operating-system default is used).
22792 Note that on GNU/Linux systems, the kernel must be configured to allow
22793 processes to use a congestion-control algorithm not in the default set;
22794 otherwise, it will deny these requests with ``Operation not permitted''.
22795 To see which algorithms are available on your system and which are
22796 currently permitted for use, look at the contents of the files
22797 @file{tcp_available_congestion_control} and
22798 @file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
22801 As an example, to have Transmission Daemon use
22802 @uref{http://www-ece.rice.edu/networks/TCP-LP/,the TCP Low Priority
22803 congestion-control algorithm}, you'll need to modify your kernel
22804 configuration to build in support for the algorithm, then update your
22805 operating-system configuration to allow its use by adding a
22806 @code{sysctl-service-type} service (or updating the existing one's
22807 configuration) with lines like the following:
22810 (service sysctl-service-type
22811 (sysctl-configuration
22813 ("net.ipv4.tcp_allowed_congestion_control" .
22814 "reno cubic lp"))))
22817 The Transmission Daemon configuration can then be updated with
22820 (peer-congestion-algorithm "lp")
22823 and the system reconfigured to have the changes take effect.
22825 Defaults to @samp{disabled}.
22829 @deftypevr {@code{transmission-daemon-configuration} parameter} tcp-type-of-service peer-socket-tos
22830 The type of service to request in outgoing @acronym{TCP} packets, one of
22831 @code{default}, @code{low-cost}, @code{throughput}, @code{low-delay} and
22832 @code{reliability}.
22834 Defaults to @samp{default}.
22838 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-global
22839 The global limit on the number of connected peers.
22841 Defaults to @samp{200}.
22845 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-per-torrent
22846 The per-torrent limit on the number of connected peers.
22848 Defaults to @samp{50}.
22852 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer upload-slots-per-torrent
22853 The maximum number of peers to which the daemon will upload data
22854 simultaneously for each torrent.
22856 Defaults to @samp{14}.
22860 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-id-ttl-hours
22861 The maximum lifespan, in hours, of the peer ID associated with each
22862 public torrent before it is regenerated.
22864 Defaults to @samp{6}.
22868 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean blocklist-enabled?
22869 When @code{#t}, the daemon will ignore peers mentioned in the blocklist
22870 it has most recently downloaded from @code{blocklist-url}.
22872 Defaults to @samp{#f}.
22876 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string blocklist-url
22877 The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
22878 @file{.dat} format) to be periodically downloaded and applied when
22879 @code{blocklist-enabled?} is @code{#t}.
22881 Defaults to @samp{disabled}.
22885 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean download-queue-enabled?
22886 If @code{#t}, the daemon will be limited to downloading at most
22887 @code{download-queue-size} non-stalled torrents simultaneously.
22889 Defaults to @samp{#t}.
22893 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer download-queue-size
22894 The size of the daemon's download queue, which limits the number of
22895 non-stalled torrents it will download at any one time when
22896 @code{download-queue-enabled?} is @code{#t}.
22898 Defaults to @samp{5}.
22902 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean seed-queue-enabled?
22903 If @code{#t}, the daemon will be limited to seeding at most
22904 @code{seed-queue-size} non-stalled torrents simultaneously.
22906 Defaults to @samp{#f}.
22910 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer seed-queue-size
22911 The size of the daemon's seed queue, which limits the number of
22912 non-stalled torrents it will seed at any one time when
22913 @code{seed-queue-enabled?} is @code{#t}.
22915 Defaults to @samp{10}.
22919 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean queue-stalled-enabled?
22920 When @code{#t}, the daemon will consider torrents for which it has not
22921 shared data in the past @code{queue-stalled-minutes} minutes to be
22922 stalled and not count them against its @code{download-queue-size} and
22923 @code{seed-queue-size} limits.
22925 Defaults to @samp{#t}.
22929 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer queue-stalled-minutes
22930 The maximum period, in minutes, a torrent may be idle before it is
22931 considered to be stalled, when @code{queue-stalled-enabled?} is
22934 Defaults to @samp{30}.
22938 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean ratio-limit-enabled?
22939 When @code{#t}, a torrent being seeded will automatically be paused once
22940 it reaches the ratio specified by @code{ratio-limit}.
22942 Defaults to @samp{#f}.
22946 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-rational ratio-limit
22947 The ratio at which a torrent being seeded will be paused, when
22948 @code{ratio-limit-enabled?} is @code{#t}.
22950 Defaults to @samp{2.0}.
22954 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean idle-seeding-limit-enabled?
22955 When @code{#t}, a torrent being seeded will automatically be paused once
22956 it has been idle for @code{idle-seeding-limit} minutes.
22958 Defaults to @samp{#f}.
22962 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer idle-seeding-limit
22963 The maximum period, in minutes, a torrent being seeded may be idle
22964 before it is paused, when @code{idle-seeding-limit-enabled?} is
22967 Defaults to @samp{30}.
22971 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean dht-enabled?
22972 Enable @uref{http://bittorrent.org/beps/bep_0005.html,the distributed
22973 hash table (@acronym{DHT}) protocol}, which supports the use of
22974 trackerless torrents.
22976 Defaults to @samp{#t}.
22980 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean lpd-enabled?
22981 Enable @uref{https://en.wikipedia.org/wiki/Local_Peer_Discovery,local
22982 peer discovery} (@acronym{LPD}), which allows the discovery of peers on
22983 the local network and may reduce the amount of data sent over the public
22986 Defaults to @samp{#f}.
22990 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean pex-enabled?
22991 Enable @uref{https://en.wikipedia.org/wiki/Peer_exchange,peer exchange}
22992 (@acronym{PEX}), which reduces the daemon's reliance on external
22993 trackers and may improve its performance.
22995 Defaults to @samp{#t}.
22999 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean utp-enabled?
23000 Enable @uref{http://bittorrent.org/beps/bep_0029.html,the micro
23001 transport protocol} (@acronym{uTP}), which aims to reduce the impact of
23002 BitTorrent traffic on other users of the local network while maintaining
23003 full utilization of the available bandwidth.
23005 Defaults to @samp{#t}.
23009 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-enabled?
23010 If @code{#t}, enable the remote procedure call (@acronym{RPC})
23011 interface, which allows remote control of the daemon via its Web
23012 interface, the @command{transmission-remote} command-line client, and
23015 Defaults to @samp{#t}.
23019 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-bind-address
23020 The IP address at which to listen for @acronym{RPC} connections, or
23021 ``0.0.0.0'' to listen at all available IP addresses.
23023 Defaults to @samp{"0.0.0.0"}.
23027 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number rpc-port
23028 The port on which to listen for @acronym{RPC} connections.
23030 Defaults to @samp{9091}.
23034 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-url
23035 The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.
23037 Defaults to @samp{"/transmission/"}.
23041 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-authentication-required?
23042 When @code{#t}, clients must authenticate (see @code{rpc-username} and
23043 @code{rpc-password}) when using the @acronym{RPC} interface. Note this
23044 has the side effect of disabling host-name whitelisting (see
23045 @code{rpc-host-whitelist-enabled?}.
23047 Defaults to @samp{#f}.
23051 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string rpc-username
23052 The username required by clients to access the @acronym{RPC} interface
23053 when @code{rpc-authentication-required?} is @code{#t}.
23055 Defaults to @samp{disabled}.
23059 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-transmission-password-hash rpc-password
23060 The password required by clients to access the @acronym{RPC} interface
23061 when @code{rpc-authentication-required?} is @code{#t}. This must be
23062 specified using a password hash in the format recognized by Transmission
23063 clients, either copied from an existing @file{settings.json} file or
23064 generated using the @code{transmission-password-hash} procedure.
23066 Defaults to @samp{disabled}.
23070 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-whitelist-enabled?
23071 When @code{#t}, @acronym{RPC} requests will be accepted only when they
23072 originate from an address specified in @code{rpc-whitelist}.
23074 Defaults to @samp{#t}.
23078 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-whitelist
23079 The list of IP and IPv6 addresses from which @acronym{RPC} requests will
23080 be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards
23081 may be specified using @samp{*}.
23083 Defaults to @samp{("127.0.0.1" "::1")}.
23087 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-host-whitelist-enabled?
23088 When @code{#t}, @acronym{RPC} requests will be accepted only when they
23089 are addressed to a host named in @code{rpc-host-whitelist}. Note that
23090 requests to ``localhost'' or ``localhost.'', or to a numeric address,
23091 are always accepted regardless of these settings.
23093 Note also this functionality is disabled when
23094 @code{rpc-authentication-required?} is @code{#t}.
23096 Defaults to @samp{#t}.
23100 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-host-whitelist
23101 The list of host names recognized by the @acronym{RPC} server when
23102 @code{rpc-host-whitelist-enabled?} is @code{#t}.
23104 Defaults to @samp{()}.
23108 @deftypevr {@code{transmission-daemon-configuration} parameter} message-level message-level
23109 The minimum severity level of messages to be logged (to
23110 @file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
23111 logging), @code{error}, @code{info} and @code{debug}.
23113 Defaults to @samp{info}.
23117 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean start-added-torrents?
23118 When @code{#t}, torrents are started as soon as they are added;
23119 otherwise, they are added in ``paused'' state.
23121 Defaults to @samp{#t}.
23125 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean script-torrent-done-enabled?
23126 When @code{#t}, the script specified by
23127 @code{script-torrent-done-filename} will be invoked each time a torrent
23130 Defaults to @samp{#f}.
23134 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-file-object script-torrent-done-filename
23135 A file name or file-like object specifying a script to run each time a
23136 torrent completes, when @code{script-torrent-done-enabled?} is
23139 Defaults to @samp{disabled}.
23143 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean scrape-paused-torrents-enabled?
23144 When @code{#t}, the daemon will scrape trackers for a torrent even when
23145 the torrent is paused.
23147 Defaults to @samp{#t}.
23151 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer cache-size-mb
23152 The amount of memory, in megabytes, to allocate for the daemon's
23153 in-memory cache. A larger value may increase performance by reducing
23154 the frequency of disk I/O.
23156 Defaults to @samp{4}.
23160 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean prefetch-enabled?
23161 When @code{#t}, the daemon will try to improve I/O performance by
23162 hinting to the operating system which data is likely to be read next
23163 from disk to satisfy requests from peers.
23165 Defaults to @samp{#t}.
23170 @c %end of fragment
23174 @node Monitoring Services
23175 @subsection Monitoring Services
23177 @subsubheading Tailon Service
23179 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
23180 viewing and searching log files.
23182 The following example will configure the service with default values.
23183 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
23186 (service tailon-service-type)
23189 The following example customises more of the Tailon configuration,
23190 adding @command{sed} to the list of allowed commands.
23193 (service tailon-service-type
23194 (tailon-configuration
23196 (tailon-configuration-file
23197 (allowed-commands '("tail" "grep" "awk" "sed"))))))
23201 @deftp {Data Type} tailon-configuration
23202 Data type representing the configuration of Tailon.
23203 This type has the following parameters:
23206 @item @code{config-file} (default: @code{(tailon-configuration-file)})
23207 The configuration file to use for Tailon. This can be set to a
23208 @dfn{tailon-configuration-file} record value, or any gexp
23209 (@pxref{G-Expressions}).
23211 For example, to instead use a local file, the @code{local-file} function
23215 (service tailon-service-type
23216 (tailon-configuration
23217 (config-file (local-file "./my-tailon.conf"))))
23220 @item @code{package} (default: @code{tailon})
23221 The tailon package to use.
23226 @deftp {Data Type} tailon-configuration-file
23227 Data type representing the configuration options for Tailon.
23228 This type has the following parameters:
23231 @item @code{files} (default: @code{(list "/var/log")})
23232 List of files to display. The list can include strings for a single file
23233 or directory, or a list, where the first item is the name of a
23234 subsection, and the remaining items are the files or directories in that
23237 @item @code{bind} (default: @code{"localhost:8080"})
23238 Address and port to which Tailon should bind on.
23240 @item @code{relative-root} (default: @code{#f})
23241 URL path to use for Tailon, set to @code{#f} to not use a path.
23243 @item @code{allow-transfers?} (default: @code{#t})
23244 Allow downloading the log files in the web interface.
23246 @item @code{follow-names?} (default: @code{#t})
23247 Allow tailing of not-yet existent files.
23249 @item @code{tail-lines} (default: @code{200})
23250 Number of lines to read initially from each file.
23252 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
23253 Commands to allow running. By default, @code{sed} is disabled.
23255 @item @code{debug?} (default: @code{#f})
23256 Set @code{debug?} to @code{#t} to show debug messages.
23258 @item @code{wrap-lines} (default: @code{#t})
23259 Initial line wrapping state in the web interface. Set to @code{#t} to
23260 initially wrap lines (the default), or to @code{#f} to initially not
23263 @item @code{http-auth} (default: @code{#f})
23264 HTTP authentication type to use. Set to @code{#f} to disable
23265 authentication (the default). Supported values are @code{"digest"} or
23268 @item @code{users} (default: @code{#f})
23269 If HTTP authentication is enabled (see @code{http-auth}), access will be
23270 restricted to the credentials provided here. To configure users, use a
23271 list of pairs, where the first element of the pair is the username, and
23272 the 2nd element of the pair is the password.
23275 (tailon-configuration-file
23276 (http-auth "basic")
23277 (users '(("user1" . "password1")
23278 ("user2" . "password2"))))
23285 @subsubheading Darkstat Service
23287 Darkstat is a packet sniffer that captures network traffic, calculates
23288 statistics about usage, and serves reports over HTTP.
23290 @defvar {Scheme Variable} darkstat-service-type
23291 This is the service type for the
23292 @uref{https://unix4lyfe.org/darkstat/, darkstat}
23293 service, its value must be a @code{darkstat-configuration} record as in
23297 (service darkstat-service-type
23298 (darkstat-configuration
23299 (interface "eno1")))
23303 @deftp {Data Type} darkstat-configuration
23304 Data type representing the configuration of @command{darkstat}.
23307 @item @code{package} (default: @code{darkstat})
23308 The darkstat package to use.
23310 @item @code{interface}
23311 Capture traffic on the specified network interface.
23313 @item @code{port} (default: @code{"667"})
23314 Bind the web interface to the specified port.
23316 @item @code{bind-address} (default: @code{"127.0.0.1"})
23317 Bind the web interface to the specified address.
23319 @item @code{base} (default: @code{"/"})
23320 Specify the path of the base URL@. This can be useful if
23321 @command{darkstat} is accessed via a reverse proxy.
23326 @subsubheading Prometheus Node Exporter Service
23328 @cindex prometheus-node-exporter
23329 The Prometheus ``node exporter'' makes hardware and operating system statistics
23330 provided by the Linux kernel available for the Prometheus monitoring system.
23331 This service should be deployed on all physical nodes and virtual machines,
23332 where monitoring these statistics is desirable.
23334 @defvar {Scheme variable} prometheus-node-exporter-service-type
23335 This is the service type for the
23336 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
23337 service, its value must be a @code{prometheus-node-exporter-configuration}.
23340 (service prometheus-node-exporter-service-type)
23344 @deftp {Data Type} prometheus-node-exporter-configuration
23345 Data type representing the configuration of @command{node_exporter}.
23348 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
23349 The prometheus-node-exporter package to use.
23351 @item @code{web-listen-address} (default: @code{":9100"})
23352 Bind the web interface to the specified address.
23354 @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
23355 This directory can be used to export metrics specific to this machine.
23356 Files containing metrics in the text format, with the filename ending in
23357 @code{.prom} should be placed in this directory.
23359 @item @code{extra-options} (default: @code{'()})
23360 Extra options to pass to the Prometheus node exporter.
23365 @subsubheading Zabbix server
23366 @cindex zabbix zabbix-server
23367 Zabbix provides monitoring metrics, among others network utilization, CPU load
23368 and disk space consumption:
23371 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
23372 @item Auto-discovery of servers and network devices and interfaces.
23373 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
23374 @item Distributed monitoring with centralized web administration.
23375 @item Native high performance agents.
23376 @item SLA, and ITIL KPI metrics on reporting.
23377 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
23378 @item Remote command execution through Zabbix proxies.
23381 @c %start of fragment
23383 Available @code{zabbix-server-configuration} fields are:
23385 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
23386 The zabbix-server package.
23390 @deftypevr {@code{zabbix-server-configuration} parameter} string user
23391 User who will run the Zabbix server.
23393 Defaults to @samp{"zabbix"}.
23397 @deftypevr {@code{zabbix-server-configuration} parameter} group group
23398 Group who will run the Zabbix server.
23400 Defaults to @samp{"zabbix"}.
23404 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
23405 Database host name.
23407 Defaults to @samp{"127.0.0.1"}.
23411 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
23414 Defaults to @samp{"zabbix"}.
23418 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
23421 Defaults to @samp{"zabbix"}.
23425 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
23426 Database password. Please, use @code{include-files} with
23427 @code{DBPassword=SECRET} inside a specified file instead.
23429 Defaults to @samp{""}.
23433 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
23436 Defaults to @samp{5432}.
23440 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
23441 Specifies where log messages are written to:
23445 @code{system} - syslog.
23448 @code{file} - file specified with @code{log-file} parameter.
23451 @code{console} - standard output.
23455 Defaults to @samp{""}.
23459 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
23460 Log file name for @code{log-type} @code{file} parameter.
23462 Defaults to @samp{"/var/log/zabbix/server.log"}.
23466 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
23469 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
23473 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
23474 The location of certificate authority (CA) files for SSL server
23475 certificate verification.
23477 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
23481 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
23482 Location of SSL client certificates.
23484 Defaults to @samp{"/etc/ssl/certs"}.
23488 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
23489 Extra options will be appended to Zabbix server configuration file.
23491 Defaults to @samp{""}.
23495 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
23496 You may include individual files or all files in a directory in the
23497 configuration file.
23499 Defaults to @samp{()}.
23503 @c %end of fragment
23505 @subsubheading Zabbix agent
23506 @cindex zabbix zabbix-agent
23508 Zabbix agent gathers information for Zabbix server.
23510 @c %start of fragment
23512 Available @code{zabbix-agent-configuration} fields are:
23514 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
23515 The zabbix-agent package.
23519 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
23520 User who will run the Zabbix agent.
23522 Defaults to @samp{"zabbix"}.
23526 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
23527 Group who will run the Zabbix agent.
23529 Defaults to @samp{"zabbix"}.
23533 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
23534 Unique, case sensitive hostname which is required for active checks and
23535 must match hostname as configured on the server.
23537 Defaults to @samp{""}.
23541 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
23542 Specifies where log messages are written to:
23546 @code{system} - syslog.
23549 @code{file} - file specified with @code{log-file} parameter.
23552 @code{console} - standard output.
23556 Defaults to @samp{""}.
23560 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
23561 Log file name for @code{log-type} @code{file} parameter.
23563 Defaults to @samp{"/var/log/zabbix/agent.log"}.
23567 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
23570 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
23574 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
23575 List of IP addresses, optionally in CIDR notation, or hostnames of
23576 Zabbix servers and Zabbix proxies. Incoming connections will be
23577 accepted only from the hosts listed here.
23579 Defaults to @samp{("127.0.0.1")}.
23583 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
23584 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
23585 proxies for active checks. If port is not specified, default port is
23586 used. If this parameter is not specified, active checks are disabled.
23588 Defaults to @samp{("127.0.0.1")}.
23592 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
23593 Extra options will be appended to Zabbix server configuration file.
23595 Defaults to @samp{""}.
23599 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
23600 You may include individual files or all files in a directory in the
23601 configuration file.
23603 Defaults to @samp{()}.
23607 @c %end of fragment
23609 @subsubheading Zabbix front-end
23610 @cindex zabbix zabbix-front-end
23612 This service provides a WEB interface to Zabbix server.
23614 @c %start of fragment
23616 Available @code{zabbix-front-end-configuration} fields are:
23618 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
23619 NGINX configuration.
23623 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
23624 Database host name.
23626 Defaults to @samp{"localhost"}.
23630 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
23633 Defaults to @samp{5432}.
23637 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
23640 Defaults to @samp{"zabbix"}.
23644 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
23647 Defaults to @samp{"zabbix"}.
23651 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
23652 Database password. Please, use @code{db-secret-file} instead.
23654 Defaults to @samp{""}.
23658 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
23659 Secret file containing the credentials for the Zabbix front-end. The value
23660 must be a local file name, not a G-expression. You are expected to create
23661 this file manually. Its contents will be copied into @file{zabbix.conf.php}
23662 as the value of @code{$DB['PASSWORD']}.
23664 Defaults to @samp{""}.
23668 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
23669 Zabbix server hostname.
23671 Defaults to @samp{"localhost"}.
23675 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
23676 Zabbix server port.
23678 Defaults to @samp{10051}.
23683 @c %end of fragment
23685 @node Kerberos Services
23686 @subsection Kerberos Services
23689 The @code{(gnu services kerberos)} module provides services relating to
23690 the authentication protocol @dfn{Kerberos}.
23692 @subsubheading Krb5 Service
23694 Programs using a Kerberos client library normally
23695 expect a configuration file in @file{/etc/krb5.conf}.
23696 This service generates such a file from a definition provided in the
23697 operating system declaration.
23698 It does not cause any daemon to be started.
23700 No ``keytab'' files are provided by this service---you must explicitly create them.
23701 This service is known to work with the MIT client library, @code{mit-krb5}.
23702 Other implementations have not been tested.
23704 @defvr {Scheme Variable} krb5-service-type
23705 A service type for Kerberos 5 clients.
23709 Here is an example of its use:
23711 (service krb5-service-type
23712 (krb5-configuration
23713 (default-realm "EXAMPLE.COM")
23714 (allow-weak-crypto? #t)
23717 (name "EXAMPLE.COM")
23718 (admin-server "groucho.example.com")
23719 (kdc "karl.example.com"))
23722 (admin-server "kerb-admin.argrx.edu")
23723 (kdc "keys.argrx.edu"))))))
23727 This example provides a Kerberos@tie{}5 client configuration which:
23729 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
23730 of which have distinct administration servers and key distribution centers;
23731 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
23732 specified by clients;
23733 @item Accepts services which only support encryption types known to be weak.
23736 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
23737 Only the most commonly used ones are described here.
23738 For a full list, and more detailed explanation of each, see the MIT
23739 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
23743 @deftp {Data Type} krb5-realm
23744 @cindex realm, kerberos
23747 This field is a string identifying the name of the realm.
23748 A common convention is to use the fully qualified DNS name of your organization,
23749 converted to upper case.
23751 @item @code{admin-server}
23752 This field is a string identifying the host where the administration server is
23756 This field is a string identifying the key distribution center
23761 @deftp {Data Type} krb5-configuration
23764 @item @code{allow-weak-crypto?} (default: @code{#f})
23765 If this flag is @code{#t} then services which only offer encryption algorithms
23766 known to be weak will be accepted.
23768 @item @code{default-realm} (default: @code{#f})
23769 This field should be a string identifying the default Kerberos
23770 realm for the client.
23771 You should set this field to the name of your Kerberos realm.
23772 If this value is @code{#f}
23773 then a realm must be specified with every Kerberos principal when invoking programs
23774 such as @command{kinit}.
23776 @item @code{realms}
23777 This should be a non-empty list of @code{krb5-realm} objects, which clients may
23779 Normally, one of them will have a @code{name} field matching the @code{default-realm}
23785 @subsubheading PAM krb5 Service
23788 The @code{pam-krb5} service allows for login authentication and password
23789 management via Kerberos.
23790 You will need this service if you want PAM enabled applications to authenticate
23791 users using Kerberos.
23793 @defvr {Scheme Variable} pam-krb5-service-type
23794 A service type for the Kerberos 5 PAM module.
23797 @deftp {Data Type} pam-krb5-configuration
23798 Data type representing the configuration of the Kerberos 5 PAM module.
23799 This type has the following parameters:
23801 @item @code{pam-krb5} (default: @code{pam-krb5})
23802 The pam-krb5 package to use.
23804 @item @code{minimum-uid} (default: @code{1000})
23805 The smallest user ID for which Kerberos authentications should be attempted.
23806 Local accounts with lower values will silently fail to authenticate.
23811 @node LDAP Services
23812 @subsection LDAP Services
23814 @cindex nslcd, LDAP service
23816 The @code{(gnu services authentication)} module provides the
23817 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
23818 server. In addition to configuring the service itself, you may want to add
23819 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
23820 Switch} for detailed information.
23822 Here is a simple operating system declaration with a default configuration of
23823 the @code{nslcd-service-type} and a Name Service Switch configuration that
23824 consults the @code{ldap} name service last:
23827 (use-service-modules authentication)
23828 (use-modules (gnu system nss))
23834 (service nslcd-service-type)
23835 (service dhcp-client-service-type)
23837 (name-service-switch
23838 (let ((services (list (name-service (name "db"))
23839 (name-service (name "files"))
23840 (name-service (name "ldap")))))
23841 (name-service-switch
23842 (inherit %mdns-host-lookup-nss)
23843 (password services)
23846 (netgroup services)
23847 (gshadow services)))))
23850 @c %start of generated documentation for nslcd-configuration
23852 Available @code{nslcd-configuration} fields are:
23854 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
23855 The @code{nss-pam-ldapd} package to use.
23859 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
23860 The number of threads to start that can handle requests and perform LDAP
23861 queries. Each thread opens a separate connection to the LDAP server.
23862 The default is to start 5 threads.
23864 Defaults to @samp{disabled}.
23868 @deftypevr {@code{nslcd-configuration} parameter} string uid
23869 This specifies the user id with which the daemon should be run.
23871 Defaults to @samp{"nslcd"}.
23875 @deftypevr {@code{nslcd-configuration} parameter} string gid
23876 This specifies the group id with which the daemon should be run.
23878 Defaults to @samp{"nslcd"}.
23882 @deftypevr {@code{nslcd-configuration} parameter} log-option log
23883 This option controls the way logging is done via a list containing
23884 SCHEME and LEVEL@. The SCHEME argument may either be the symbols
23885 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
23886 argument is optional and specifies the log level. The log level may be
23887 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
23888 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
23889 specified log level or higher are logged.
23891 Defaults to @samp{("/var/log/nslcd" info)}.
23895 @deftypevr {@code{nslcd-configuration} parameter} list uri
23896 The list of LDAP server URIs. Normally, only the first server will be
23897 used with the following servers as fall-back.
23899 Defaults to @samp{("ldap://localhost:389/")}.
23903 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
23904 The version of the LDAP protocol to use. The default is to use the
23905 maximum version supported by the LDAP library.
23907 Defaults to @samp{disabled}.
23911 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
23912 Specifies the distinguished name with which to bind to the directory
23913 server for lookups. The default is to bind anonymously.
23915 Defaults to @samp{disabled}.
23919 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
23920 Specifies the credentials with which to bind. This option is only
23921 applicable when used with binddn.
23923 Defaults to @samp{disabled}.
23927 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
23928 Specifies the distinguished name to use when the root user tries to
23929 modify a user's password using the PAM module.
23931 Defaults to @samp{disabled}.
23935 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
23936 Specifies the credentials with which to bind if the root user tries to
23937 change a user's password. This option is only applicable when used with
23940 Defaults to @samp{disabled}.
23944 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
23945 Specifies the SASL mechanism to be used when performing SASL
23948 Defaults to @samp{disabled}.
23952 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
23953 Specifies the SASL realm to be used when performing SASL authentication.
23955 Defaults to @samp{disabled}.
23959 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
23960 Specifies the authentication identity to be used when performing SASL
23963 Defaults to @samp{disabled}.
23967 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
23968 Specifies the authorization identity to be used when performing SASL
23971 Defaults to @samp{disabled}.
23975 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
23976 Determines whether the LDAP server host name should be canonicalised. If
23977 this is enabled the LDAP library will do a reverse host name lookup. By
23978 default, it is left up to the LDAP library whether this check is
23981 Defaults to @samp{disabled}.
23985 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
23986 Set the name for the GSS-API Kerberos credentials cache.
23988 Defaults to @samp{disabled}.
23992 @deftypevr {@code{nslcd-configuration} parameter} string base
23993 The directory search base.
23995 Defaults to @samp{"dc=example,dc=com"}.
23999 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
24000 Specifies the search scope (subtree, onelevel, base or children). The
24001 default scope is subtree; base scope is almost never useful for name
24002 service lookups; children scope is not supported on all servers.
24004 Defaults to @samp{(subtree)}.
24008 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
24009 Specifies the policy for dereferencing aliases. The default policy is
24010 to never dereference aliases.
24012 Defaults to @samp{disabled}.
24016 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
24017 Specifies whether automatic referral chasing should be enabled. The
24018 default behaviour is to chase referrals.
24020 Defaults to @samp{disabled}.
24024 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
24025 This option allows for custom attributes to be looked up instead of the
24026 default RFC 2307 attributes. It is a list of maps, each consisting of
24027 the name of a map, the RFC 2307 attribute to match and the query
24028 expression for the attribute as it is available in the directory.
24030 Defaults to @samp{()}.
24034 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
24035 A list of filters consisting of the name of a map to which the filter
24036 applies and an LDAP search filter expression.
24038 Defaults to @samp{()}.
24042 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
24043 Specifies the time limit in seconds to use when connecting to the
24044 directory server. The default value is 10 seconds.
24046 Defaults to @samp{disabled}.
24050 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
24051 Specifies the time limit (in seconds) to wait for a response from the
24052 LDAP server. A value of zero, which is the default, is to wait
24053 indefinitely for searches to be completed.
24055 Defaults to @samp{disabled}.
24059 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
24060 Specifies the period if inactivity (in seconds) after which the con‐
24061 nection to the LDAP server will be closed. The default is not to time
24064 Defaults to @samp{disabled}.
24068 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
24069 Specifies the number of seconds to sleep when connecting to all LDAP
24070 servers fails. By default one second is waited between the first
24071 failure and the first retry.
24073 Defaults to @samp{disabled}.
24077 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
24078 Specifies the time after which the LDAP server is considered to be
24079 permanently unavailable. Once this time is reached retries will be done
24080 only once per this time period. The default value is 10 seconds.
24082 Defaults to @samp{disabled}.
24086 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
24087 Specifies whether to use SSL/TLS or not (the default is not to). If
24088 'start-tls is specified then StartTLS is used rather than raw LDAP over
24091 Defaults to @samp{disabled}.
24095 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
24096 Specifies what checks to perform on a server-supplied certificate. The
24097 meaning of the values is described in the ldap.conf(5) manual page.
24099 Defaults to @samp{disabled}.
24103 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
24104 Specifies the directory containing X.509 certificates for peer authen‐
24105 tication. This parameter is ignored when using GnuTLS.
24107 Defaults to @samp{disabled}.
24111 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
24112 Specifies the path to the X.509 certificate for peer authentication.
24114 Defaults to @samp{disabled}.
24118 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
24119 Specifies the path to an entropy source. This parameter is ignored when
24122 Defaults to @samp{disabled}.
24126 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
24127 Specifies the ciphers to use for TLS as a string.
24129 Defaults to @samp{disabled}.
24133 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
24134 Specifies the path to the file containing the local certificate for
24135 client TLS authentication.
24137 Defaults to @samp{disabled}.
24141 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
24142 Specifies the path to the file containing the private key for client TLS
24145 Defaults to @samp{disabled}.
24149 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
24150 Set this to a number greater than 0 to request paged results from the
24151 LDAP server in accordance with RFC2696. The default (0) is to not
24152 request paged results.
24154 Defaults to @samp{disabled}.
24158 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
24159 This option prevents group membership lookups through LDAP for the
24160 specified users. Alternatively, the value 'all-local may be used. With
24161 that value nslcd builds a full list of non-LDAP users on startup.
24163 Defaults to @samp{disabled}.
24167 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
24168 This option ensures that LDAP users with a numeric user id lower than
24169 the specified value are ignored.
24171 Defaults to @samp{disabled}.
24175 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
24176 This option specifies an offset that is added to all LDAP numeric user
24177 ids. This can be used to avoid user id collisions with local users.
24179 Defaults to @samp{disabled}.
24183 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
24184 This option specifies an offset that is added to all LDAP numeric group
24185 ids. This can be used to avoid user id collisions with local groups.
24187 Defaults to @samp{disabled}.
24191 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
24192 If this option is set, the member attribute of a group may point to
24193 another group. Members of nested groups are also returned in the higher
24194 level group and parent groups are returned when finding groups for a
24195 specific user. The default is not to perform extra searches for nested
24198 Defaults to @samp{disabled}.
24202 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
24203 If this option is set, the group member list is not retrieved when
24204 looking up groups. Lookups for finding which groups a user belongs to
24205 will remain functional so the user will likely still get the correct
24206 groups assigned on login.
24208 Defaults to @samp{disabled}.
24212 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
24213 If this option is set, functions which cause all user/group entries to
24214 be loaded from the directory will not succeed in doing so. This can
24215 dramatically reduce LDAP server load in situations where there are a
24216 great number of users and/or groups. This option is not recommended for
24217 most configurations.
24219 Defaults to @samp{disabled}.
24223 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
24224 This option can be used to specify how user and group names are verified
24225 within the system. This pattern is used to check all user and group
24226 names that are requested and returned from LDAP.
24228 Defaults to @samp{disabled}.
24232 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
24233 This specifies whether or not to perform searches using case-insensitive
24234 matching. Enabling this could open up the system to authorization
24235 bypass vulnerabilities and introduce nscd cache poisoning
24236 vulnerabilities which allow denial of service.
24238 Defaults to @samp{disabled}.
24242 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
24243 This option specifies whether password policy controls are requested and
24244 handled from the LDAP server when performing user authentication.
24246 Defaults to @samp{disabled}.
24250 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
24251 By default nslcd performs an LDAP search with the user's credentials
24252 after BIND (authentication) to ensure that the BIND operation was
24253 successful. The default search is a simple check to see if the user's
24254 DN exists. A search filter can be specified that will be used instead.
24255 It should return at least one entry.
24257 Defaults to @samp{disabled}.
24261 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
24262 This option allows flexible fine tuning of the authorisation check that
24263 should be performed. The search filter specified is executed and if any
24264 entries match, access is granted, otherwise access is denied.
24266 Defaults to @samp{disabled}.
24270 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
24271 If this option is set password modification using pam_ldap will be
24272 denied and the specified message will be presented to the user instead.
24273 The message can be used to direct the user to an alternative means of
24274 changing their password.
24276 Defaults to @samp{disabled}.
24280 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
24281 List of pam service names for which LDAP authentication should suffice.
24283 Defaults to @samp{()}.
24287 @c %end of generated documentation for nslcd-configuration
24291 @subsection Web Services
24296 The @code{(gnu services web)} module provides the Apache HTTP Server,
24297 the nginx web server, and also a fastcgi wrapper daemon.
24299 @subsubheading Apache HTTP Server
24301 @deffn {Scheme Variable} httpd-service-type
24302 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
24303 (@dfn{httpd}). The value for this service type is a
24304 @code{httpd-configuration} record.
24306 A simple example configuration is given below.
24309 (service httpd-service-type
24310 (httpd-configuration
24313 (server-name "www.example.com")
24314 (document-root "/srv/http/www.example.com")))))
24317 Other services can also extend the @code{httpd-service-type} to add to
24321 (simple-service 'www.example.com-server httpd-service-type
24325 (list (string-join '("ServerName www.example.com"
24326 "DocumentRoot /srv/http/www.example.com")
24331 The details for the @code{httpd-configuration}, @code{httpd-module},
24332 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
24335 @deffn {Data Type} httpd-configuration
24336 This data type represents the configuration for the httpd service.
24339 @item @code{package} (default: @code{httpd})
24340 The httpd package to use.
24342 @item @code{pid-file} (default: @code{"/var/run/httpd"})
24343 The pid file used by the shepherd-service.
24345 @item @code{config} (default: @code{(httpd-config-file)})
24346 The configuration file to use with the httpd service. The default value
24347 is a @code{httpd-config-file} record, but this can also be a different
24348 G-expression that generates a file, for example a @code{plain-file}. A
24349 file outside of the store can also be specified through a string.
24354 @deffn {Data Type} httpd-module
24355 This data type represents a module for the httpd service.
24359 The name of the module.
24362 The file for the module. This can be relative to the httpd package being
24363 used, the absolute location of a file, or a G-expression for a file
24364 within the store, for example @code{(file-append mod-wsgi
24365 "/modules/mod_wsgi.so")}.
24370 @defvr {Scheme Variable} %default-httpd-modules
24371 A default list of @code{httpd-module} objects.
24374 @deffn {Data Type} httpd-config-file
24375 This data type represents a configuration file for the httpd service.
24378 @item @code{modules} (default: @code{%default-httpd-modules})
24379 The modules to load. Additional modules can be added here, or loaded by
24380 additional configuration.
24382 For example, in order to handle requests for PHP files, you can use Apache’s
24383 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
24386 (service httpd-service-type
24387 (httpd-configuration
24392 (name "proxy_module")
24393 (file "modules/mod_proxy.so"))
24395 (name "proxy_fcgi_module")
24396 (file "modules/mod_proxy_fcgi.so"))
24397 %default-httpd-modules))
24398 (extra-config (list "\
24399 <FilesMatch \\.php$>
24400 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
24401 </FilesMatch>"))))))
24402 (service php-fpm-service-type
24403 (php-fpm-configuration
24404 (socket "/var/run/php-fpm.sock")
24405 (socket-group "httpd")))
24408 @item @code{server-root} (default: @code{httpd})
24409 The @code{ServerRoot} in the configuration file, defaults to the httpd
24410 package. Directives including @code{Include} and @code{LoadModule} are
24411 taken as relative to the server root.
24413 @item @code{server-name} (default: @code{#f})
24414 The @code{ServerName} in the configuration file, used to specify the
24415 request scheme, hostname and port that the server uses to identify
24418 This doesn't need to be set in the server config, and can be specified
24419 in virtual hosts. The default is @code{#f} to not specify a
24422 @item @code{document-root} (default: @code{"/srv/http"})
24423 The @code{DocumentRoot} from which files will be served.
24425 @item @code{listen} (default: @code{'("80")})
24426 The list of values for the @code{Listen} directives in the config
24427 file. The value should be a list of strings, when each string can
24428 specify the port number to listen on, and optionally the IP address and
24431 @item @code{pid-file} (default: @code{"/var/run/httpd"})
24432 The @code{PidFile} to use. This should match the @code{pid-file} set in
24433 the @code{httpd-configuration} so that the Shepherd service is
24434 configured correctly.
24436 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
24437 The @code{ErrorLog} to which the server will log errors.
24439 @item @code{user} (default: @code{"httpd"})
24440 The @code{User} which the server will answer requests as.
24442 @item @code{group} (default: @code{"httpd"})
24443 The @code{Group} which the server will answer requests as.
24445 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
24446 A flat list of strings and G-expressions which will be added to the end
24447 of the configuration file.
24449 Any values which the service is extended with will be appended to this
24455 @deffn {Data Type} httpd-virtualhost
24456 This data type represents a virtualhost configuration block for the httpd service.
24458 These should be added to the extra-config for the httpd-service.
24461 (simple-service 'www.example.com-server httpd-service-type
24465 (list (string-join '("ServerName www.example.com"
24466 "DocumentRoot /srv/http/www.example.com")
24471 @item @code{addresses-and-ports}
24472 The addresses and ports for the @code{VirtualHost} directive.
24474 @item @code{contents}
24475 The contents of the @code{VirtualHost} directive, this should be a list
24476 of strings and G-expressions.
24481 @subsubheading NGINX
24483 @deffn {Scheme Variable} nginx-service-type
24484 Service type for the @uref{https://nginx.org/,NGinx} web server. The
24485 value for this service type is a @code{<nginx-configuration>} record.
24487 A simple example configuration is given below.
24490 (service nginx-service-type
24491 (nginx-configuration
24493 (list (nginx-server-configuration
24494 (server-name '("www.example.com"))
24495 (root "/srv/http/www.example.com"))))))
24498 In addition to adding server blocks to the service configuration
24499 directly, this service can be extended by other services to add server
24500 blocks, as in this example:
24503 (simple-service 'my-extra-server nginx-service-type
24504 (list (nginx-server-configuration
24505 (root "/srv/http/extra-website")
24506 (try-files (list "$uri" "$uri/index.html")))))
24510 At startup, @command{nginx} has not yet read its configuration file, so
24511 it uses a default file to log error messages. If it fails to load its
24512 configuration file, that is where error messages are logged. After the
24513 configuration file is loaded, the default error log file changes as per
24514 configuration. In our case, startup error messages can be found in
24515 @file{/var/run/nginx/logs/error.log}, and after configuration in
24516 @file{/var/log/nginx/error.log}. The second location can be changed
24517 with the @var{log-directory} configuration option.
24519 @deffn {Data Type} nginx-configuration
24520 This data type represents the configuration for NGinx. Some
24521 configuration can be done through this and the other provided record
24522 types, or alternatively, a config file can be provided.
24525 @item @code{nginx} (default: @code{nginx})
24526 The nginx package to use.
24528 @item @code{log-directory} (default: @code{"/var/log/nginx"})
24529 The directory to which NGinx will write log files.
24531 @item @code{run-directory} (default: @code{"/var/run/nginx"})
24532 The directory in which NGinx will create a pid file, and write temporary
24535 @item @code{server-blocks} (default: @code{'()})
24536 A list of @dfn{server blocks} to create in the generated configuration
24537 file, the elements should be of type
24538 @code{<nginx-server-configuration>}.
24540 The following example would setup NGinx to serve @code{www.example.com}
24541 from the @code{/srv/http/www.example.com} directory, without using
24544 (service nginx-service-type
24545 (nginx-configuration
24547 (list (nginx-server-configuration
24548 (server-name '("www.example.com"))
24549 (root "/srv/http/www.example.com"))))))
24552 @item @code{upstream-blocks} (default: @code{'()})
24553 A list of @dfn{upstream blocks} to create in the generated configuration
24554 file, the elements should be of type
24555 @code{<nginx-upstream-configuration>}.
24557 Configuring upstreams through the @code{upstream-blocks} can be useful
24558 when combined with @code{locations} in the
24559 @code{<nginx-server-configuration>} records. The following example
24560 creates a server configuration with one location configuration, that
24561 will proxy requests to a upstream configuration, which will handle
24562 requests with two servers.
24567 (nginx-configuration
24569 (list (nginx-server-configuration
24570 (server-name '("www.example.com"))
24571 (root "/srv/http/www.example.com")
24574 (nginx-location-configuration
24576 (body '("proxy_pass http://server-proxy;"))))))))
24578 (list (nginx-upstream-configuration
24579 (name "server-proxy")
24580 (servers (list "server1.example.com"
24581 "server2.example.com")))))))
24584 @item @code{file} (default: @code{#f})
24585 If a configuration @var{file} is provided, this will be used, rather than
24586 generating a configuration file from the provided @code{log-directory},
24587 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
24588 proper operation, these arguments should match what is in @var{file} to ensure
24589 that the directories are created when the service is activated.
24591 This can be useful if you have an existing configuration file, or it's
24592 not possible to do what is required through the other parts of the
24593 nginx-configuration record.
24595 @item @code{server-names-hash-bucket-size} (default: @code{#f})
24596 Bucket size for the server names hash tables, defaults to @code{#f} to
24597 use the size of the processors cache line.
24599 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
24600 Maximum bucket size for the server names hash tables.
24602 @item @code{modules} (default: @code{'()})
24603 List of nginx dynamic modules to load. This should be a list of file
24604 names of loadable modules, as in this example:
24609 (file-append nginx-accept-language-module "\
24610 /etc/nginx/modules/ngx_http_accept_language_module.so")
24611 (file-append nginx-lua-module "\
24612 /etc/nginx/modules/ngx_http_lua_module.so")))
24615 @item @code{lua-package-path} (default: @code{'()})
24616 List of nginx lua packages to load. This should be a list of package
24617 names of loadable lua modules, as in this example:
24620 (lua-package-path (list lua-resty-core
24627 @item @code{lua-package-cpath} (default: @code{'()})
24628 List of nginx lua C packages to load. This should be a list of package
24629 names of loadable lua C modules, as in this example:
24632 (lua-package-cpath (list lua-resty-signal))
24635 @item @code{global-directives} (default: @code{'((events . ()))})
24636 Association list of global directives for the top level of the nginx
24637 configuration. Values may themselves be association lists.
24641 `((worker_processes . 16)
24643 (events . ((worker_connections . 1024)))))
24646 @item @code{extra-content} (default: @code{""})
24647 Extra content for the @code{http} block. Should be string or a string
24648 valued G-expression.
24653 @deftp {Data Type} nginx-server-configuration
24654 Data type representing the configuration of an nginx server block.
24655 This type has the following parameters:
24658 @item @code{listen} (default: @code{'("80" "443 ssl")})
24659 Each @code{listen} directive sets the address and port for IP, or the
24660 path for a UNIX-domain socket on which the server will accept requests.
24661 Both address and port, or only address or only port can be specified.
24662 An address may also be a hostname, for example:
24665 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
24668 @item @code{server-name} (default: @code{(list 'default)})
24669 A list of server names this server represents. @code{'default} represents the
24670 default server for connections matching no other server.
24672 @item @code{root} (default: @code{"/srv/http"})
24673 Root of the website nginx will serve.
24675 @item @code{locations} (default: @code{'()})
24676 A list of @dfn{nginx-location-configuration} or
24677 @dfn{nginx-named-location-configuration} records to use within this
24680 @item @code{index} (default: @code{(list "index.html")})
24681 Index files to look for when clients ask for a directory. If it cannot be found,
24682 Nginx will send the list of files in the directory.
24684 @item @code{try-files} (default: @code{'()})
24685 A list of files whose existence is checked in the specified order.
24686 @code{nginx} will use the first file it finds to process the request.
24688 @item @code{ssl-certificate} (default: @code{#f})
24689 Where to find the certificate for secure connections. Set it to @code{#f} if
24690 you don't have a certificate or you don't want to use HTTPS.
24692 @item @code{ssl-certificate-key} (default: @code{#f})
24693 Where to find the private key for secure connections. Set it to @code{#f} if
24694 you don't have a key or you don't want to use HTTPS.
24696 @item @code{server-tokens?} (default: @code{#f})
24697 Whether the server should add its configuration to response.
24699 @item @code{raw-content} (default: @code{'()})
24700 A list of raw lines added to the server block.
24705 @deftp {Data Type} nginx-upstream-configuration
24706 Data type representing the configuration of an nginx @code{upstream}
24707 block. This type has the following parameters:
24711 Name for this group of servers.
24713 @item @code{servers}
24714 Specify the addresses of the servers in the group. The address can be
24715 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
24716 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
24717 prefix @samp{unix:}. For addresses using an IP address or domain name,
24718 the default port is 80, and a different port can be specified
24724 @deftp {Data Type} nginx-location-configuration
24725 Data type representing the configuration of an nginx @code{location}
24726 block. This type has the following parameters:
24730 URI which this location block matches.
24732 @anchor{nginx-location-configuration body}
24734 Body of the location block, specified as a list of strings. This can contain
24736 configuration directives. For example, to pass requests to a upstream
24737 server group defined using an @code{nginx-upstream-configuration} block,
24738 the following directive would be specified in the body @samp{(list "proxy_pass
24739 http://upstream-name;")}.
24744 @deftp {Data Type} nginx-named-location-configuration
24745 Data type representing the configuration of an nginx named location
24746 block. Named location blocks are used for request redirection, and not
24747 used for regular request processing. This type has the following
24752 Name to identify this location block.
24755 @xref{nginx-location-configuration body}, as the body for named location
24756 blocks can be used in a similar way to the
24757 @code{nginx-location-configuration body}. One restriction is that the
24758 body of a named location block cannot contain location blocks.
24763 @subsubheading Varnish Cache
24765 Varnish is a fast cache server that sits in between web applications
24766 and end users. It proxies requests from clients and caches the
24767 accessed URLs such that multiple requests for the same resource only
24768 creates one request to the back-end.
24770 @defvr {Scheme Variable} varnish-service-type
24771 Service type for the Varnish daemon.
24774 @deftp {Data Type} varnish-configuration
24775 Data type representing the @code{varnish} service configuration.
24776 This type has the following parameters:
24779 @item @code{package} (default: @code{varnish})
24780 The Varnish package to use.
24782 @item @code{name} (default: @code{"default"})
24783 A name for this Varnish instance. Varnish will create a directory in
24784 @file{/var/varnish/} with this name and keep temporary files there. If
24785 the name starts with a forward slash, it is interpreted as an absolute
24788 Pass the @code{-n} argument to other Varnish programs to connect to the
24789 named instance, e.g.@: @command{varnishncsa -n default}.
24791 @item @code{backend} (default: @code{"localhost:8080"})
24792 The backend to use. This option has no effect if @code{vcl} is set.
24794 @item @code{vcl} (default: #f)
24795 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
24796 is @code{#f}, Varnish will proxy @code{backend} using the default
24797 configuration. Otherwise this must be a file-like object with valid
24800 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
24801 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
24802 can do something along these lines:
24805 (define %gnu-mirror
24806 (plain-file "gnu.vcl"
24808 backend gnu @{ .host = \"www.gnu.org\"; @}"))
24812 (services (cons (service varnish-service-type
24813 (varnish-configuration
24815 (vcl %gnu-mirror)))
24819 The configuration of an already running Varnish instance can be inspected
24820 and changed using the @command{varnishadm} program.
24822 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
24823 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
24824 comprehensive documentation on Varnish and its configuration language.
24826 @item @code{listen} (default: @code{'("localhost:80")})
24827 List of addresses Varnish will listen on.
24829 @item @code{storage} (default: @code{'("malloc,128m")})
24830 List of storage backends that will be available in VCL.
24832 @item @code{parameters} (default: @code{'()})
24833 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
24835 @item @code{extra-options} (default: @code{'()})
24836 Additional arguments to pass to the @command{varnishd} process.
24841 @subsubheading Patchwork
24843 Patchwork is a patch tracking system. It can collect patches sent to a
24844 mailing list, and display them in a web interface.
24846 @defvr {Scheme Variable} patchwork-service-type
24847 Service type for Patchwork.
24850 The following example is an example of a minimal service for Patchwork, for
24851 the @code{patchwork.example.com} domain.
24854 (service patchwork-service-type
24855 (patchwork-configuration
24856 (domain "patchwork.example.com")
24858 (patchwork-settings-module
24859 (allowed-hosts (list domain))
24860 (default-from-email "patchwork@@patchwork.example.com")))
24861 (getmail-retriever-config
24862 (getmail-retriever-configuration
24863 (type "SimpleIMAPSSLRetriever")
24864 (server "imap.example.com")
24866 (username "patchwork")
24868 (list (file-append coreutils "/bin/cat")
24869 "/etc/getmail-patchwork-imap-password"))
24871 '((mailboxes . ("Patches"))))))))
24875 There are three records for configuring the Patchwork service. The
24876 @code{<patchwork-configuration>} relates to the configuration for Patchwork
24877 within the HTTPD service.
24879 The @code{settings-module} field within the @code{<patchwork-configuration>}
24880 record can be populated with the @code{<patchwork-settings-module>} record,
24881 which describes a settings module that is generated within the Guix store.
24883 For the @code{database-configuration} field within the
24884 @code{<patchwork-settings-module>}, the
24885 @code{<patchwork-database-configuration>} must be used.
24887 @deftp {Data Type} patchwork-configuration
24888 Data type representing the Patchwork service configuration. This type has the
24889 following parameters:
24892 @item @code{patchwork} (default: @code{patchwork})
24893 The Patchwork package to use.
24895 @item @code{domain}
24896 The domain to use for Patchwork, this is used in the HTTPD service virtual
24899 @item @code{settings-module}
24900 The settings module to use for Patchwork. As a Django application, Patchwork
24901 is configured with a Python module containing the settings. This can either be
24902 an instance of the @code{<patchwork-settings-module>} record, any other record
24903 that represents the settings in the store, or a directory outside of the
24906 @item @code{static-path} (default: @code{"/static/"})
24907 The path under which the HTTPD service should serve the static files.
24909 @item @code{getmail-retriever-config}
24910 The getmail-retriever-configuration record value to use with
24911 Patchwork. Getmail will be configured with this value, the messages will be
24912 delivered to Patchwork.
24917 @deftp {Data Type} patchwork-settings-module
24918 Data type representing a settings module for Patchwork. Some of these
24919 settings relate directly to Patchwork, but others relate to Django, the web
24920 framework used by Patchwork, or the Django Rest Framework library. This type
24921 has the following parameters:
24924 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
24925 The database connection settings used for Patchwork. See the
24926 @code{<patchwork-database-configuration>} record type for more information.
24928 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
24929 Patchwork, as a Django web application uses a secret key for cryptographically
24930 signing values. This file should contain a unique unpredictable value.
24932 If this file does not exist, it will be created and populated with a random
24933 value by the patchwork-setup shepherd service.
24935 This setting relates to Django.
24937 @item @code{allowed-hosts}
24938 A list of valid hosts for this Patchwork service. This should at least include
24939 the domain specified in the @code{<patchwork-configuration>} record.
24941 This is a Django setting.
24943 @item @code{default-from-email}
24944 The email address from which Patchwork should send email by default.
24946 This is a Patchwork setting.
24948 @item @code{static-url} (default: @code{#f})
24949 The URL to use when serving static assets. It can be part of a URL, or a full
24950 URL, but must end in a @code{/}.
24952 If the default value is used, the @code{static-path} value from the
24953 @code{<patchwork-configuration>} record will be used.
24955 This is a Django setting.
24957 @item @code{admins} (default: @code{'()})
24958 Email addresses to send the details of errors that occur. Each value should
24959 be a list containing two elements, the name and then the email address.
24961 This is a Django setting.
24963 @item @code{debug?} (default: @code{#f})
24964 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
24965 messages will be shown.
24967 This is a Django setting.
24969 @item @code{enable-rest-api?} (default: @code{#t})
24970 Whether to enable the Patchwork REST API.
24972 This is a Patchwork setting.
24974 @item @code{enable-xmlrpc?} (default: @code{#t})
24975 Whether to enable the XML RPC API.
24977 This is a Patchwork setting.
24979 @item @code{force-https-links?} (default: @code{#t})
24980 Whether to use HTTPS links on Patchwork pages.
24982 This is a Patchwork setting.
24984 @item @code{extra-settings} (default: @code{""})
24985 Extra code to place at the end of the Patchwork settings module.
24990 @deftp {Data Type} patchwork-database-configuration
24991 Data type representing the database configuration for Patchwork.
24994 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
24995 The database engine to use.
24997 @item @code{name} (default: @code{"patchwork"})
24998 The name of the database to use.
25000 @item @code{user} (default: @code{"httpd"})
25001 The user to connect to the database as.
25003 @item @code{password} (default: @code{""})
25004 The password to use when connecting to the database.
25006 @item @code{host} (default: @code{""})
25007 The host to make the database connection to.
25009 @item @code{port} (default: @code{""})
25010 The port on which to connect to the database.
25015 @subsubheading Mumi
25017 @cindex Mumi, Debbugs Web interface
25018 @cindex Debbugs, Mumi Web interface
25019 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
25020 Web interface to the Debbugs bug tracker, by default for
25021 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
25022 but it also fetches and indexes mail retrieved from Debbugs.
25024 @defvr {Scheme Variable} mumi-service-type
25025 This is the service type for Mumi.
25028 @deftp {Data Type} mumi-configuration
25029 Data type representing the Mumi service configuration. This type has the
25033 @item @code{mumi} (default: @code{mumi})
25034 The Mumi package to use.
25036 @item @code{mailer?} (default: @code{#true})
25037 Whether to enable or disable the mailer component.
25039 @item @code{mumi-configuration-sender}
25040 The email address used as the sender for comments.
25042 @item @code{mumi-configuration-smtp}
25043 A URI to configure the SMTP settings for Mailutils. This could be
25044 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
25045 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
25046 mailutils, GNU@tie{}Mailutils}.
25052 @subsubheading FastCGI
25055 FastCGI is an interface between the front-end and the back-end of a web
25056 service. It is a somewhat legacy facility; new web services should
25057 generally just talk HTTP between the front-end and the back-end.
25058 However there are a number of back-end services such as PHP or the
25059 optimized HTTP Git repository access that use FastCGI, so we have
25060 support for it in Guix.
25062 To use FastCGI, you configure the front-end web server (e.g., nginx) to
25063 dispatch some subset of its requests to the fastcgi backend, which
25064 listens on a local TCP or UNIX socket. There is an intermediary
25065 @code{fcgiwrap} program that sits between the actual backend process and
25066 the web server. The front-end indicates which backend program to run,
25067 passing that information to the @code{fcgiwrap} process.
25069 @defvr {Scheme Variable} fcgiwrap-service-type
25070 A service type for the @code{fcgiwrap} FastCGI proxy.
25073 @deftp {Data Type} fcgiwrap-configuration
25074 Data type representing the configuration of the @code{fcgiwrap} service.
25075 This type has the following parameters:
25077 @item @code{package} (default: @code{fcgiwrap})
25078 The fcgiwrap package to use.
25080 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
25081 The socket on which the @code{fcgiwrap} process should listen, as a
25082 string. Valid @var{socket} values include
25083 @code{unix:@var{/path/to/unix/socket}},
25084 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
25085 @code{tcp6:[@var{ipv6_addr}]:port}.
25087 @item @code{user} (default: @code{fcgiwrap})
25088 @itemx @code{group} (default: @code{fcgiwrap})
25089 The user and group names, as strings, under which to run the
25090 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
25091 the user asks for the specific user or group names @code{fcgiwrap} that
25092 the corresponding user and/or group is present on the system.
25094 It is possible to configure a FastCGI-backed web service to pass HTTP
25095 authentication information from the front-end to the back-end, and to
25096 allow @code{fcgiwrap} to run the back-end process as a corresponding
25097 local user. To enable this capability on the back-end, run
25098 @code{fcgiwrap} as the @code{root} user and group. Note that this
25099 capability also has to be configured on the front-end as well.
25104 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
25105 with some additional features useful for sites of any size.
25107 These features include:
25109 @item Adaptive process spawning
25110 @item Basic statistics (similar to Apache's mod_status)
25111 @item Advanced process management with graceful stop/start
25112 @item Ability to start workers with different uid/gid/chroot/environment
25113 and different php.ini (replaces safe_mode)
25114 @item Stdout & stderr logging
25115 @item Emergency restart in case of accidental opcode cache destruction
25116 @item Accelerated upload support
25117 @item Support for a "slowlog"
25118 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
25119 a special function to finish request & flush all data while continuing to do
25120 something time-consuming (video converting, stats processing, etc.)
25122 ...@: and much more.
25124 @defvr {Scheme Variable} php-fpm-service-type
25125 A Service type for @code{php-fpm}.
25128 @deftp {Data Type} php-fpm-configuration
25129 Data Type for php-fpm service configuration.
25131 @item @code{php} (default: @code{php})
25132 The php package to use.
25133 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
25134 The address on which to accept FastCGI requests. Valid syntaxes are:
25136 @item @code{"ip.add.re.ss:port"}
25137 Listen on a TCP socket to a specific address on a specific port.
25138 @item @code{"port"}
25139 Listen on a TCP socket to all addresses on a specific port.
25140 @item @code{"/path/to/unix/socket"}
25141 Listen on a unix socket.
25144 @item @code{user} (default: @code{php-fpm})
25145 User who will own the php worker processes.
25146 @item @code{group} (default: @code{php-fpm})
25147 Group of the worker processes.
25148 @item @code{socket-user} (default: @code{php-fpm})
25149 User who can speak to the php-fpm socket.
25150 @item @code{socket-group} (default: @code{nginx})
25151 Group that can speak to the php-fpm socket.
25152 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
25153 The process id of the php-fpm process is written to this file
25154 once the service has started.
25155 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
25156 Log for the php-fpm master process.
25157 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
25158 Detailed settings for the php-fpm process manager.
25161 @item @code{<php-fpm-dynamic-process-manager-configuration>}
25162 @item @code{<php-fpm-static-process-manager-configuration>}
25163 @item @code{<php-fpm-on-demand-process-manager-configuration>}
25165 @item @code{display-errors} (default @code{#f})
25166 Determines whether php errors and warning should be sent to clients
25167 and displayed in their browsers.
25168 This is useful for local php development, but a security risk for public sites,
25169 as error messages can reveal passwords and personal data.
25170 @item @code{timezone} (default @code{#f})
25171 Specifies @code{php_admin_value[date.timezone]} parameter.
25172 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
25173 This file will log the @code{stderr} outputs of php worker processes.
25174 Can be set to @code{#f} to disable logging.
25175 @item @code{file} (default @code{#f})
25176 An optional override of the whole configuration.
25177 You can use the @code{mixed-text-file} function or an absolute filepath for it.
25178 @item @code{php-ini-file} (default @code{#f})
25179 An optional override of the default php settings.
25180 It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
25181 You can use the @code{mixed-text-file} function or an absolute filepath for it.
25183 For local development it is useful to set a higher timeout and memory
25184 limit for spawned php processes. This be accomplished with the
25185 following operating system configuration snippet:
25187 (define %local-php-ini
25188 (plain-file "php.ini"
25190 max_execution_time = 1800"))
25194 (services (cons (service php-fpm-service-type
25195 (php-fpm-configuration
25196 (php-ini-file %local-php-ini)))
25200 Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
25201 directives} for comprehensive documentation on the acceptable
25202 @file{php.ini} directives.
25206 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
25207 Data Type for the @code{dynamic} php-fpm process manager. With the
25208 @code{dynamic} process manager, spare worker processes are kept around
25209 based on it's configured limits.
25211 @item @code{max-children} (default: @code{5})
25212 Maximum of worker processes.
25213 @item @code{start-servers} (default: @code{2})
25214 How many worker processes should be started on start-up.
25215 @item @code{min-spare-servers} (default: @code{1})
25216 How many spare worker processes should be kept around at minimum.
25217 @item @code{max-spare-servers} (default: @code{3})
25218 How many spare worker processes should be kept around at maximum.
25222 @deftp {Data type} php-fpm-static-process-manager-configuration
25223 Data Type for the @code{static} php-fpm process manager. With the
25224 @code{static} process manager, an unchanging number of worker processes
25227 @item @code{max-children} (default: @code{5})
25228 Maximum of worker processes.
25232 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
25233 Data Type for the @code{on-demand} php-fpm process manager. With the
25234 @code{on-demand} process manager, worker processes are only created as
25237 @item @code{max-children} (default: @code{5})
25238 Maximum of worker processes.
25239 @item @code{process-idle-timeout} (default: @code{10})
25240 The time in seconds after which a process with no requests is killed.
25245 @deffn {Scheme Procedure} nginx-php-location @
25246 [#:nginx-package nginx] @
25247 [socket (string-append "/var/run/php" @
25248 (version-major (package-version php)) @
25250 A helper function to quickly add php to an @code{nginx-server-configuration}.
25253 A simple services setup for nginx with php can look like this:
25255 (services (cons* (service dhcp-client-service-type)
25256 (service php-fpm-service-type)
25257 (service nginx-service-type
25258 (nginx-server-configuration
25259 (server-name '("example.com"))
25260 (root "/srv/http/")
25262 (list (nginx-php-location)))
25264 (ssl-certificate #f)
25265 (ssl-certificate-key #f)))
25269 @cindex cat-avatar-generator
25270 The cat avatar generator is a simple service to demonstrate the use of php-fpm
25271 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
25272 the hash of a user's email address.
25274 @deffn {Scheme Procedure} cat-avatar-generator-service @
25275 [#:cache-dir "/var/cache/cat-avatar-generator"] @
25276 [#:package cat-avatar-generator] @
25277 [#:configuration (nginx-server-configuration)]
25278 Returns an nginx-server-configuration that inherits @code{configuration}. It
25279 extends the nginx configuration to add a server block that serves @code{package},
25280 a version of cat-avatar-generator. During execution, cat-avatar-generator will
25281 be able to use @code{cache-dir} as its cache directory.
25284 A simple setup for cat-avatar-generator can look like this:
25286 (services (cons* (cat-avatar-generator-service
25288 (nginx-server-configuration
25289 (server-name '("example.com"))))
25294 @subsubheading Hpcguix-web
25296 @cindex hpcguix-web
25297 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
25298 program is a customizable web interface to browse Guix packages,
25299 initially designed for users of high-performance computing (HPC)
25302 @defvr {Scheme Variable} hpcguix-web-service-type
25303 The service type for @code{hpcguix-web}.
25306 @deftp {Data Type} hpcguix-web-configuration
25307 Data type for the hpcguix-web service configuration.
25311 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
25312 configuration. The main items available in this spec are:
25315 @item @code{title-prefix} (default: @code{"hpcguix | "})
25316 The page title prefix.
25318 @item @code{guix-command} (default: @code{"guix"})
25319 The @command{guix} command.
25321 @item @code{package-filter-proc} (default: @code{(const #t)})
25322 A procedure specifying how to filter packages that are displayed.
25324 @item @code{package-page-extension-proc} (default: @code{(const '())})
25325 Extension package for @code{hpcguix-web}.
25327 @item @code{menu} (default: @code{'()})
25328 Additional entry in page @code{menu}.
25330 @item @code{channels} (default: @code{%default-channels})
25331 List of channels from which the package list is built (@pxref{Channels}).
25333 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
25334 The expiration time, in seconds, after which the package list is rebuilt from
25335 the latest instances of the given channels.
25338 See the hpcguix-web repository for a
25339 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
25342 @item @code{package} (default: @code{hpcguix-web})
25343 The hpcguix-web package to use.
25347 A typical hpcguix-web service declaration looks like this:
25350 (service hpcguix-web-service-type
25351 (hpcguix-web-configuration
25353 #~(define site-config
25354 (hpcweb-configuration
25355 (title-prefix "Guix-HPC - ")
25356 (menu '(("/about" "ABOUT"))))))))
25360 The hpcguix-web service periodically updates the package list it publishes by
25361 pulling channels from Git. To that end, it needs to access X.509 certificates
25362 so that it can authenticate Git servers when communicating over HTTPS, and it
25363 assumes that @file{/etc/ssl/certs} contains those certificates.
25365 Thus, make sure to add @code{nss-certs} or another certificate package to the
25366 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
25367 more information on X.509 certificates.
25370 @subsubheading gmnisrv
25373 The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
25374 simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
25376 @deffn {Scheme Variable} gmnisrv-service-type
25377 This is the type of the gmnisrv service, whose value should be a
25378 @code{gmnisrv-configuration} object, as in this example:
25381 (service gmnisrv-service-type
25382 (gmnisrv-configuration
25383 (config-file (local-file "./my-gmnisrv.ini"))))
25387 @deftp {Data Type} gmnisrv-configuration
25388 Data type representing the configuration of gmnisrv.
25391 @item @code{package} (default: @var{gmnisrv})
25392 Package object of the gmnisrv server.
25394 @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
25395 File-like object of the gmnisrv configuration file to use. The default
25396 configuration listens on port 1965 and serves files from
25397 @file{/srv/gemini}. Certificates are stored in
25398 @file{/var/lib/gemini/certs}. For more information, run @command{man
25399 gmnisrv} and @command{man gmnisrv.ini}.
25404 @subsubheading Agate
25407 The @uref{gemini://qwertqwefsday.eu/agate.gmi, Agate}
25408 (@uref{https://github.com/mbrubeck/agate, GitHub page over HTTPS})
25409 program is a simple @uref{https://gemini.circumlunar.space/, Gemini}
25410 protocol server written in Rust.
25412 @deffn {Scheme Variable} agate-service-type
25413 This is the type of the agate service, whose value should be an
25414 @code{agate-service-type} object, as in this example:
25417 (service agate-service-type
25418 (agate-configuration
25419 (content "/srv/gemini")
25420 (cert "/srv/cert.pem")
25421 (key "/srv/key.rsa")))
25424 The example above represents the minimal tweaking necessary to get Agate
25425 up and running. Specifying the path to the certificate and key is
25426 always necessary, as the Gemini protocol requires TLS by default.
25428 To obtain a certificate and a key, you could, for example, use OpenSSL,
25429 running a command similar to the following example:
25432 openssl req -x509 -newkey rsa:4096 -keyout key.rsa -out cert.pem \
25433 -days 3650 -nodes -subj "/CN=example.com"
25436 Of course, you'll have to replace @i{example.com} with your own domain
25437 name, and then point the Agate configuration towards the path of the
25438 generated key and certificate.
25442 @deftp {Data Type} agate-configuration
25443 Data type representing the configuration of Agate.
25446 @item @code{package} (default: @code{agate})
25447 The package object of the Agate server.
25449 @item @code{content} (default: @file{"/srv/gemini"})
25450 The directory from which Agate will serve files.
25452 @item @code{cert} (default: @code{#f})
25453 The path to the TLS certificate PEM file to be used for encrypted
25454 connections. Must be filled in with a value from the user.
25456 @item @code{key} (default: @code{#f})
25457 The path to the PKCS8 private key file to be used for encrypted
25458 connections. Must be filled in with a value from the user.
25460 @item @code{addr} (default: @code{'("0.0.0.0:1965" "[::]:1965")})
25461 A list of the addresses to listen on.
25463 @item @code{hostname} (default: @code{#f})
25464 The domain name of this Gemini server. Optional.
25466 @item @code{lang} (default: @code{#f})
25467 RFC 4646 language code(s) for text/gemini documents. Optional.
25469 @item @code{silent?} (default: @code{#f})
25470 Set to @code{#t} to disable logging output.
25472 @item @code{serve-secret?} (default: @code{#f})
25473 Set to @code{#t} to serve secret files (files/directories starting with
25476 @item @code{log-ip?} (default: @code{#t})
25477 Whether or not to output IP addresses when logging.
25479 @item @code{user} (default: @code{"agate"})
25480 Owner of the @code{agate} process.
25482 @item @code{group} (default: @code{"agate"})
25483 Owner's group of the @code{agate} process.
25485 @item @code{log-file} (default: @file{"/var/log/agate.log"})
25486 The file which should store the logging output of Agate.
25491 @node Certificate Services
25492 @subsection Certificate Services
25495 @cindex HTTP, HTTPS
25496 @cindex Let's Encrypt
25497 @cindex TLS certificates
25498 The @code{(gnu services certbot)} module provides a service to
25499 automatically obtain a valid TLS certificate from the Let's Encrypt
25500 certificate authority. These certificates can then be used to serve
25501 content securely over HTTPS or other TLS-based protocols, with the
25502 knowledge that the client will be able to verify the server's
25505 @url{https://letsencrypt.org/, Let's Encrypt} provides the
25506 @code{certbot} tool to automate the certification process. This tool
25507 first securely generates a key on the server. It then makes a request
25508 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
25509 checks that the request originates from the host in question by using a
25510 challenge-response protocol, requiring the server to provide its
25511 response over HTTP@. If that protocol completes successfully, the CA
25512 signs the key, resulting in a certificate. That certificate is valid
25513 for a limited period of time, and therefore to continue to provide TLS
25514 services, the server needs to periodically ask the CA to renew its
25517 The certbot service automates this process: the initial key
25518 generation, the initial certification request to the Let's Encrypt
25519 service, the web server challenge/response integration, writing the
25520 certificate to disk, the automated periodic renewals, and the deployment
25521 tasks associated with the renewal (e.g.@: reloading services, copying keys
25522 with different permissions).
25524 Certbot is run twice a day, at a random minute within the hour. It
25525 won't do anything until your certificates are due for renewal or
25526 revoked, but running it regularly would give your service a chance of
25527 staying online in case a Let's Encrypt-initiated revocation happened for
25530 By using this service, you agree to the ACME Subscriber Agreement, which
25531 can be found there:
25532 @url{https://acme-v01.api.letsencrypt.org/directory}.
25534 @defvr {Scheme Variable} certbot-service-type
25535 A service type for the @code{certbot} Let's Encrypt client. Its value
25536 must be a @code{certbot-configuration} record as in this example:
25539 (define %nginx-deploy-hook
25541 "nginx-deploy-hook"
25542 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
25543 (kill pid SIGHUP))))
25545 (service certbot-service-type
25546 (certbot-configuration
25547 (email "foo@@example.net")
25550 (certificate-configuration
25551 (domains '("example.net" "www.example.net"))
25552 (deploy-hook %nginx-deploy-hook))
25553 (certificate-configuration
25554 (domains '("bar.example.net")))))))
25557 See below for details about @code{certbot-configuration}.
25560 @deftp {Data Type} certbot-configuration
25561 Data type representing the configuration of the @code{certbot} service.
25562 This type has the following parameters:
25565 @item @code{package} (default: @code{certbot})
25566 The certbot package to use.
25568 @item @code{webroot} (default: @code{/var/www})
25569 The directory from which to serve the Let's Encrypt challenge/response
25572 @item @code{certificates} (default: @code{()})
25573 A list of @code{certificates-configuration}s for which to generate
25574 certificates and request signatures. Each certificate has a @code{name}
25575 and several @code{domains}.
25577 @item @code{email} (default: @code{#f})
25578 Optional email address used for registration and recovery contact.
25579 Setting this is encouraged as it allows you to receive important
25580 notifications about the account and issued certificates.
25582 @item @code{server} (default: @code{#f})
25583 Optional URL of ACME server. Setting this overrides certbot's default,
25584 which is the Let's Encrypt server.
25586 @item @code{rsa-key-size} (default: @code{2048})
25587 Size of the RSA key.
25589 @item @code{default-location} (default: @i{see below})
25590 The default @code{nginx-location-configuration}. Because @code{certbot}
25591 needs to be able to serve challenges and responses, it needs to be able
25592 to run a web server. It does so by extending the @code{nginx} web
25593 service with an @code{nginx-server-configuration} listening on the
25594 @var{domains} on port 80, and which has a
25595 @code{nginx-location-configuration} for the @code{/.well-known/} URI
25596 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
25597 these nginx configuration data types.
25599 Requests to other URL paths will be matched by the
25600 @code{default-location}, which if present is added to all
25601 @code{nginx-server-configuration}s.
25603 By default, the @code{default-location} will issue a redirect from
25604 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
25605 you to define what to serve on your site via @code{https}.
25607 Pass @code{#f} to not issue a default location.
25611 @deftp {Data Type} certificate-configuration
25612 Data type representing the configuration of a certificate.
25613 This type has the following parameters:
25616 @item @code{name} (default: @i{see below})
25617 This name is used by Certbot for housekeeping and in file paths; it
25618 doesn't affect the content of the certificate itself. To see
25619 certificate names, run @code{certbot certificates}.
25621 Its default is the first provided domain.
25623 @item @code{domains} (default: @code{()})
25624 The first domain provided will be the subject CN of the certificate, and
25625 all domains will be Subject Alternative Names on the certificate.
25627 @item @code{challenge} (default: @code{#f})
25628 The challenge type that has to be run by certbot. If @code{#f} is specified,
25629 default to the HTTP challenge. If a value is specified, defaults to the
25630 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
25631 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
25632 and gives Let's Encrypt permission to log the public IP address of the
25633 requesting machine.
25635 @item @code{authentication-hook} (default: @code{#f})
25636 Command to be run in a shell once for each certificate challenge to be
25637 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
25638 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
25639 contains the validation string and @code{$CERTBOT_TOKEN} contains the
25640 file name of the resource requested when performing an HTTP-01 challenge.
25642 @item @code{cleanup-hook} (default: @code{#f})
25643 Command to be run in a shell once for each certificate challenge that
25644 have been answered by the @code{auth-hook}. For this command, the shell
25645 variables available in the @code{auth-hook} script are still available, and
25646 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
25647 of the @code{auth-hook} script.
25649 @item @code{deploy-hook} (default: @code{#f})
25650 Command to be run in a shell once for each successfully issued
25651 certificate. For this command, the shell variable
25652 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
25653 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
25654 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
25655 contain a space-delimited list of renewed certificate domains (for
25656 example, @samp{"example.com www.example.com"}.
25661 For each @code{certificate-configuration}, the certificate is saved to
25662 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
25663 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
25665 @subsection DNS Services
25666 @cindex DNS (domain name system)
25667 @cindex domain name system (DNS)
25669 The @code{(gnu services dns)} module provides services related to the
25670 @dfn{domain name system} (DNS). It provides a server service for hosting
25671 an @emph{authoritative} DNS server for multiple zones, slave or master.
25672 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
25673 caching and forwarding DNS server for the LAN, which uses
25674 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
25676 @subsubheading Knot Service
25678 An example configuration of an authoritative server for two zones, one master
25682 (define-zone-entries example.org.zone
25683 ;; Name TTL Class Type Data
25684 ("@@" "" "IN" "A" "127.0.0.1")
25685 ("@@" "" "IN" "NS" "ns")
25686 ("ns" "" "IN" "A" "127.0.0.1"))
25688 (define master-zone
25689 (knot-zone-configuration
25690 (domain "example.org")
25692 (origin "example.org")
25693 (entries example.org.zone)))))
25696 (knot-zone-configuration
25697 (domain "plop.org")
25698 (dnssec-policy "default")
25699 (master (list "plop-master"))))
25701 (define plop-master
25702 (knot-remote-configuration
25704 (address (list "208.76.58.171"))))
25708 (services (cons* (service knot-service-type
25709 (knot-configuration
25710 (remotes (list plop-master))
25711 (zones (list master-zone slave-zone))))
25716 @deffn {Scheme Variable} knot-service-type
25717 This is the type for the Knot DNS server.
25719 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
25720 zones, that is to say domain names you would buy from a registrar. This server
25721 is not a resolver, meaning that it can only resolve names for which it is
25722 authoritative. This server can be configured to serve zones as a master server
25723 or a slave server as a per-zone basis. Slave zones will get their data from
25724 masters, and will serve it as an authoritative server. From the point of view
25725 of a resolver, there is no difference between master and slave.
25727 The following data types are used to configure the Knot DNS server:
25730 @deftp {Data Type} knot-key-configuration
25731 Data type representing a key.
25732 This type has the following parameters:
25735 @item @code{id} (default: @code{""})
25736 An identifier for other configuration fields to refer to this key. IDs must
25737 be unique and must not be empty.
25739 @item @code{algorithm} (default: @code{#f})
25740 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
25741 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
25742 and @code{'hmac-sha512}.
25744 @item @code{secret} (default: @code{""})
25745 The secret key itself.
25750 @deftp {Data Type} knot-acl-configuration
25751 Data type representing an Access Control List (ACL) configuration.
25752 This type has the following parameters:
25755 @item @code{id} (default: @code{""})
25756 An identifier for other configuration fields to refer to this key. IDs must be
25757 unique and must not be empty.
25759 @item @code{address} (default: @code{'()})
25760 An ordered list of IP addresses, network subnets, or network ranges represented
25761 with strings. The query must match one of them. Empty value means that
25762 address match is not required.
25764 @item @code{key} (default: @code{'()})
25765 An ordered list of references to keys represented with strings. The string
25766 must match a key ID defined in a @code{knot-key-configuration}. No key means
25767 that a key is not require to match that ACL.
25769 @item @code{action} (default: @code{'()})
25770 An ordered list of actions that are permitted or forbidden by this ACL@. Possible
25771 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
25772 and @code{'update}.
25774 @item @code{deny?} (default: @code{#f})
25775 When true, the ACL defines restrictions. Listed actions are forbidden. When
25776 false, listed actions are allowed.
25781 @deftp {Data Type} zone-entry
25782 Data type representing a record entry in a zone file.
25783 This type has the following parameters:
25786 @item @code{name} (default: @code{"@@"})
25787 The name of the record. @code{"@@"} refers to the origin of the zone. Names
25788 are relative to the origin of the zone. For example, in the @code{example.org}
25789 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
25790 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
25791 refers to @code{ns.example.org}.
25793 @item @code{ttl} (default: @code{""})
25794 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
25796 @item @code{class} (default: @code{"IN"})
25797 The class of the record. Knot currently supports only @code{"IN"} and
25798 partially @code{"CH"}.
25800 @item @code{type} (default: @code{"A"})
25801 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
25802 address), NS (Name Server) and MX (Mail eXchange). Many other types are
25805 @item @code{data} (default: @code{""})
25806 The data contained in the record. For instance an IP address associated with
25807 an A record, or a domain name associated with an NS record. Remember that
25808 domain names are relative to the origin unless they end with a dot.
25813 @deftp {Data Type} zone-file
25814 Data type representing the content of a zone file.
25815 This type has the following parameters:
25818 @item @code{entries} (default: @code{'()})
25819 The list of entries. The SOA record is taken care of, so you don't need to
25820 put it in the list of entries. This list should probably contain an entry
25821 for your primary authoritative DNS server. Other than using a list of entries
25822 directly, you can use @code{define-zone-entries} to define a object containing
25823 the list of entries more easily, that you can later pass to the @code{entries}
25824 field of the @code{zone-file}.
25826 @item @code{origin} (default: @code{""})
25827 The name of your zone. This parameter cannot be empty.
25829 @item @code{ns} (default: @code{"ns"})
25830 The domain of your primary authoritative DNS server. The name is relative to
25831 the origin, unless it ends with a dot. It is mandatory that this primary
25832 DNS server corresponds to an NS record in the zone and that it is associated
25833 to an IP address in the list of entries.
25835 @item @code{mail} (default: @code{"hostmaster"})
25836 An email address people can contact you at, as the owner of the zone. This
25837 is translated as @code{<mail>@@<origin>}.
25839 @item @code{serial} (default: @code{1})
25840 The serial number of the zone. As this is used to keep track of changes by
25841 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
25842 Always increment it when you make a change in your zone.
25844 @item @code{refresh} (default: @code{(* 2 24 3600)})
25845 The frequency at which slaves will do a zone transfer. This value is a number
25846 of seconds. It can be computed by multiplications or with
25847 @code{(string->duration)}.
25849 @item @code{retry} (default: @code{(* 15 60)})
25850 The period after which a slave will retry to contact its master when it fails
25851 to do so a first time.
25853 @item @code{expiry} (default: @code{(* 14 24 3600)})
25854 Default TTL of records. Existing records are considered correct for at most
25855 this amount of time. After this period, resolvers will invalidate their cache
25856 and check again that it still exists.
25858 @item @code{nx} (default: @code{3600})
25859 Default TTL of inexistant records. This delay is usually short because you want
25860 your new domains to reach everyone quickly.
25865 @deftp {Data Type} knot-remote-configuration
25866 Data type representing a remote configuration.
25867 This type has the following parameters:
25870 @item @code{id} (default: @code{""})
25871 An identifier for other configuration fields to refer to this remote. IDs must
25872 be unique and must not be empty.
25874 @item @code{address} (default: @code{'()})
25875 An ordered list of destination IP addresses. Addresses are tried in sequence.
25876 An optional port can be given with the @@ separator. For instance:
25877 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
25879 @item @code{via} (default: @code{'()})
25880 An ordered list of source IP addresses. An empty list will have Knot choose
25881 an appropriate source IP@. An optional port can be given with the @@ separator.
25882 The default is to choose at random.
25884 @item @code{key} (default: @code{#f})
25885 A reference to a key, that is a string containing the identifier of a key
25886 defined in a @code{knot-key-configuration} field.
25891 @deftp {Data Type} knot-keystore-configuration
25892 Data type representing a keystore to hold dnssec keys.
25893 This type has the following parameters:
25896 @item @code{id} (default: @code{""})
25897 The id of the keystore. It must not be empty.
25899 @item @code{backend} (default: @code{'pem})
25900 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
25902 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
25903 The configuration string of the backend. An example for the PKCS#11 is:
25904 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
25905 For the pem backend, the string represents a path in the file system.
25910 @deftp {Data Type} knot-policy-configuration
25911 Data type representing a dnssec policy. Knot DNS is able to automatically
25912 sign your zones. It can either generate and manage your keys automatically or
25913 use keys that you generate.
25915 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
25916 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
25917 zone. In order to be trusted, the KSK needs to be present in the parent zone
25918 (usually a top-level domain). If your registrar supports dnssec, you will
25919 have to send them your KSK's hash so they can add a DS record in their zone.
25920 This is not automated and need to be done each time you change your KSK.
25922 The policy also defines the lifetime of keys. Usually, ZSK can be changed
25923 easily and use weaker cryptographic functions (they use lower parameters) in
25924 order to sign records quickly, so they are changed often. The KSK however
25925 requires manual interaction with the registrar, so they are changed less often
25926 and use stronger parameters because they sign only one record.
25928 This type has the following parameters:
25931 @item @code{id} (default: @code{""})
25932 The id of the policy. It must not be empty.
25934 @item @code{keystore} (default: @code{"default"})
25935 A reference to a keystore, that is a string containing the identifier of a
25936 keystore defined in a @code{knot-keystore-configuration} field. The
25937 @code{"default"} identifier means the default keystore (a kasp database that
25938 was setup by this service).
25940 @item @code{manual?} (default: @code{#f})
25941 Whether the key management is manual or automatic.
25943 @item @code{single-type-signing?} (default: @code{#f})
25944 When @code{#t}, use the Single-Type Signing Scheme.
25946 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
25947 An algorithm of signing keys and issued signatures.
25949 @item @code{ksk-size} (default: @code{256})
25950 The length of the KSK@. Note that this value is correct for the default
25951 algorithm, but would be unsecure for other algorithms.
25953 @item @code{zsk-size} (default: @code{256})
25954 The length of the ZSK@. Note that this value is correct for the default
25955 algorithm, but would be unsecure for other algorithms.
25957 @item @code{dnskey-ttl} (default: @code{'default})
25958 The TTL value for DNSKEY records added into zone apex. The special
25959 @code{'default} value means same as the zone SOA TTL.
25961 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
25962 The period between ZSK publication and the next rollover initiation.
25964 @item @code{propagation-delay} (default: @code{(* 24 3600)})
25965 An extra delay added for each key rollover step. This value should be high
25966 enough to cover propagation of data from the master server to all slaves.
25968 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
25969 A validity period of newly issued signatures.
25971 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
25972 A period how long before a signature expiration the signature will be refreshed.
25974 @item @code{nsec3?} (default: @code{#f})
25975 When @code{#t}, NSEC3 will be used instead of NSEC.
25977 @item @code{nsec3-iterations} (default: @code{5})
25978 The number of additional times the hashing is performed.
25980 @item @code{nsec3-salt-length} (default: @code{8})
25981 The length of a salt field in octets, which is appended to the original owner
25982 name before hashing.
25984 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
25985 The validity period of newly issued salt field.
25990 @deftp {Data Type} knot-zone-configuration
25991 Data type representing a zone served by Knot.
25992 This type has the following parameters:
25995 @item @code{domain} (default: @code{""})
25996 The domain served by this configuration. It must not be empty.
25998 @item @code{file} (default: @code{""})
25999 The file where this zone is saved. This parameter is ignored by master zones.
26000 Empty means default location that depends on the domain name.
26002 @item @code{zone} (default: @code{(zone-file)})
26003 The content of the zone file. This parameter is ignored by slave zones. It
26004 must contain a zone-file record.
26006 @item @code{master} (default: @code{'()})
26007 A list of master remotes. When empty, this zone is a master. When set, this
26008 zone is a slave. This is a list of remotes identifiers.
26010 @item @code{ddns-master} (default: @code{#f})
26011 The main master. When empty, it defaults to the first master in the list of
26014 @item @code{notify} (default: @code{'()})
26015 A list of slave remote identifiers.
26017 @item @code{acl} (default: @code{'()})
26018 A list of acl identifiers.
26020 @item @code{semantic-checks?} (default: @code{#f})
26021 When set, this adds more semantic checks to the zone.
26023 @item @code{disable-any?} (default: @code{#f})
26024 When set, this forbids queries of the ANY type.
26026 @item @code{zonefile-sync} (default: @code{0})
26027 The delay between a modification in memory and on disk. 0 means immediate
26030 @item @code{zonefile-load} (default: @code{#f})
26031 The way the zone file contents are applied during zone load. Possible values
26035 @item @code{#f} for using the default value from Knot,
26036 @item @code{'none} for not using the zone file at all,
26037 @item @code{'difference} for computing the difference between already available
26038 contents and zone contents and applying it to the current zone contents,
26039 @item @code{'difference-no-serial} for the same as @code{'difference}, but
26040 ignoring the SOA serial in the zone file, while the server takes care of it
26042 @item @code{'whole} for loading zone contents from the zone file.
26045 @item @code{journal-content} (default: @code{#f})
26046 The way the journal is used to store zone and its changes. Possible values
26047 are @code{'none} to not use it at all, @code{'changes} to store changes and
26048 @code{'all} to store contents. @code{#f} does not set this option, so the
26049 default value from Knot is used.
26051 @item @code{max-journal-usage} (default: @code{#f})
26052 The maximum size for the journal on disk. @code{#f} does not set this option,
26053 so the default value from Knot is used.
26055 @item @code{max-journal-depth} (default: @code{#f})
26056 The maximum size of the history. @code{#f} does not set this option, so the
26057 default value from Knot is used.
26059 @item @code{max-zone-size} (default: @code{#f})
26060 The maximum size of the zone file. This limit is enforced for incoming
26061 transfer and updates. @code{#f} does not set this option, so the default
26062 value from Knot is used.
26064 @item @code{dnssec-policy} (default: @code{#f})
26065 A reference to a @code{knot-policy-configuration} record, or the special
26066 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
26069 @item @code{serial-policy} (default: @code{'increment})
26070 A policy between @code{'increment} and @code{'unixtime}.
26075 @deftp {Data Type} knot-configuration
26076 Data type representing the Knot configuration.
26077 This type has the following parameters:
26080 @item @code{knot} (default: @code{knot})
26083 @item @code{run-directory} (default: @code{"/var/run/knot"})
26084 The run directory. This directory will be used for pid file and sockets.
26086 @item @code{includes} (default: @code{'()})
26087 A list of strings or file-like objects denoting other files that must be
26088 included at the top of the configuration file.
26090 @cindex secrets, Knot service
26091 This can be used to manage secrets out-of-band. For example, secret
26092 keys may be stored in an out-of-band file not managed by Guix, and
26093 thus not visible in @file{/gnu/store}---e.g., you could store secret
26094 key configuration in @file{/etc/knot/secrets.conf} and add this file
26095 to the @code{includes} list.
26097 One can generate a secret tsig key (for nsupdate and zone transfers with the
26098 keymgr command from the knot package. Note that the package is not automatically
26099 installed by the service. The following example shows how to generate a new
26103 keymgr -t mysecret > /etc/knot/secrets.conf
26104 chmod 600 /etc/knot/secrets.conf
26107 Also note that the generated key will be named @var{mysecret}, so it is the
26108 name that needs to be used in the @var{key} field of the
26109 @code{knot-acl-configuration} record and in other places that need to refer
26112 It can also be used to add configuration not supported by this interface.
26114 @item @code{listen-v4} (default: @code{"0.0.0.0"})
26115 An ip address on which to listen.
26117 @item @code{listen-v6} (default: @code{"::"})
26118 An ip address on which to listen.
26120 @item @code{listen-port} (default: @code{53})
26121 A port on which to listen.
26123 @item @code{keys} (default: @code{'()})
26124 The list of knot-key-configuration used by this configuration.
26126 @item @code{acls} (default: @code{'()})
26127 The list of knot-acl-configuration used by this configuration.
26129 @item @code{remotes} (default: @code{'()})
26130 The list of knot-remote-configuration used by this configuration.
26132 @item @code{zones} (default: @code{'()})
26133 The list of knot-zone-configuration used by this configuration.
26138 @subsubheading Knot Resolver Service
26140 @deffn {Scheme Variable} knot-resolver-service-type
26141 This is the type of the knot resolver service, whose value should be
26142 an @code{knot-resolver-configuration} object as in this example:
26145 (service knot-resolver-service-type
26146 (knot-resolver-configuration
26147 (kresd-config-file (plain-file "kresd.conf" "
26148 net.listen('192.168.0.1', 5353)
26149 user('knot-resolver', 'knot-resolver')
26150 modules = @{ 'hints > iterate', 'stats', 'predict' @}
26151 cache.size = 100 * MB
26155 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
26158 @deftp {Data Type} knot-resolver-configuration
26159 Data type representing the configuration of knot-resolver.
26162 @item @code{package} (default: @var{knot-resolver})
26163 Package object of the knot DNS resolver.
26165 @item @code{kresd-config-file} (default: %kresd.conf)
26166 File-like object of the kresd configuration file to use, by default it
26167 will listen on @code{127.0.0.1} and @code{::1}.
26169 @item @code{garbage-collection-interval} (default: 1000)
26170 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
26176 @subsubheading Dnsmasq Service
26178 @deffn {Scheme Variable} dnsmasq-service-type
26179 This is the type of the dnsmasq service, whose value should be an
26180 @code{dnsmasq-configuration} object as in this example:
26183 (service dnsmasq-service-type
26184 (dnsmasq-configuration
26186 (servers '("192.168.1.1"))))
26190 @deftp {Data Type} dnsmasq-configuration
26191 Data type representing the configuration of dnsmasq.
26194 @item @code{package} (default: @var{dnsmasq})
26195 Package object of the dnsmasq server.
26197 @item @code{no-hosts?} (default: @code{#f})
26198 When true, don't read the hostnames in /etc/hosts.
26200 @item @code{port} (default: @code{53})
26201 The port to listen on. Setting this to zero completely disables DNS
26202 responses, leaving only DHCP and/or TFTP functions.
26204 @item @code{local-service?} (default: @code{#t})
26205 Accept DNS queries only from hosts whose address is on a local subnet,
26206 ie a subnet for which an interface exists on the server.
26208 @item @code{listen-addresses} (default: @code{'()})
26209 Listen on the given IP addresses.
26211 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
26212 The file to read the IP address of the upstream nameservers from.
26214 @item @code{no-resolv?} (default: @code{#f})
26215 When true, don't read @var{resolv-file}.
26217 @item @code{servers} (default: @code{'()})
26218 Specify IP address of upstream servers directly.
26220 @item @code{addresses} (default: @code{'()})
26221 For each entry, specify an IP address to return for any host in the
26222 given domains. Queries in the domains are never forwarded and always
26223 replied to with the specified IP address.
26225 This is useful for redirecting hosts locally, for example:
26228 (service dnsmasq-service-type
26229 (dnsmasq-configuration
26231 '(; Redirect to a local web-server.
26232 "/example.org/127.0.0.1"
26233 ; Redirect subdomain to a specific IP.
26234 "/subdomain.example.org/192.168.1.42"))))
26237 Note that rules in @file{/etc/hosts} take precedence over this.
26239 @item @code{cache-size} (default: @code{150})
26240 Set the size of dnsmasq's cache. Setting the cache size to zero
26243 @item @code{negative-cache?} (default: @code{#t})
26244 When false, disable negative caching.
26246 @item @code{tftp-enable?} (default: @code{#f})
26247 Whether to enable the built-in TFTP server.
26249 @item @code{tftp-no-fail?} (default: @code{#f})
26250 If true, does not fail dnsmasq if the TFTP server could not start up.
26252 @item @code{tftp-single-port?} (default: @code{#f})
26253 Whether to use only one single port for TFTP.
26255 @item @code{tftp-secure?} (default: @code{#f})
26256 If true, only files owned by the user running the dnsmasq process are accessible.
26258 If dnsmasq is being run as root, different rules apply:
26259 @code{tftp-secure?} has no effect, but only files which have the
26260 world-readable bit set are accessible.
26262 @item @code{tftp-max} (default: @code{#f})
26263 If set, sets the maximal number of concurrent connections allowed.
26265 @item @code{tftp-mtu} (default: @code{#f})
26266 If set, sets the MTU for TFTP packets to that value.
26268 @item @code{tftp-no-blocksize?} (default: @code{#f})
26269 If true, stops the TFTP server from negotiating the blocksize with a client.
26271 @item @code{tftp-lowercase?} (default: @code{#f})
26272 Whether to convert all filenames in TFTP requests to lowercase.
26274 @item @code{tftp-port-range} (default: @code{#f})
26275 If set, fixes the dynamical ports (one per client) to the given range
26276 (@code{"<start>,<end>"}).
26278 @item @code{tftp-root} (default: @code{/var/empty,lo})
26279 Look for files to transfer using TFTP relative to the given directory.
26280 When this is set, TFTP paths which include @samp{..} are rejected, to stop clients
26281 getting outside the specified root. Absolute paths (starting with @samp{/}) are
26282 allowed, but they must be within the TFTP-root. If the optional interface
26283 argument is given, the directory is only used for TFTP requests via that
26286 @item @code{tftp-unique-root} (default: @code{#f})
26287 If set, add the IP or hardware address of the TFTP client as a path component
26288 on the end of the TFTP-root. Only valid if a TFTP root is set and the
26289 directory exists. Defaults to adding IP address (in standard dotted-quad
26292 For instance, if @option{--tftp-root} is @samp{/tftp} and client
26293 @samp{1.2.3.4} requests file @file{myfile} then the effective path will
26294 be @file{/tftp/1.2.3.4/myfile} if @file{/tftp/1.2.3.4} exists or
26295 @file{/tftp/myfile} otherwise. When @samp{=mac} is specified it will
26296 append the MAC address instead, using lowercase zero padded digits
26297 separated by dashes, e.g.: @samp{01-02-03-04-aa-bb}. Note that
26298 resolving MAC addresses is only possible if the client is in the local
26299 network or obtained a DHCP lease from dnsmasq.
26304 @subsubheading ddclient Service
26307 The ddclient service described below runs the ddclient daemon, which takes
26308 care of automatically updating DNS entries for service providers such as
26309 @uref{https://dyn.com/dns/, Dyn}.
26311 The following example show instantiates the service with its default
26315 (service ddclient-service-type)
26318 Note that ddclient needs to access credentials that are stored in a
26319 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
26320 @code{secret-file} below). You are expected to create this file manually, in
26321 an ``out-of-band'' fashion (you @emph{could} make this file part of the
26322 service configuration, for instance by using @code{plain-file}, but it will be
26323 world-readable @i{via} @file{/gnu/store}). See the examples in the
26324 @file{share/ddclient} directory of the @code{ddclient} package.
26326 @c %start of fragment
26328 Available @code{ddclient-configuration} fields are:
26330 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
26331 The ddclient package.
26335 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
26336 The period after which ddclient will retry to check IP and domain name.
26338 Defaults to @samp{300}.
26342 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
26343 Use syslog for the output.
26345 Defaults to @samp{#t}.
26349 @deftypevr {@code{ddclient-configuration} parameter} string mail
26352 Defaults to @samp{"root"}.
26356 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
26357 Mail failed update to user.
26359 Defaults to @samp{"root"}.
26363 @deftypevr {@code{ddclient-configuration} parameter} string pid
26364 The ddclient PID file.
26366 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
26370 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
26371 Enable SSL support.
26373 Defaults to @samp{#t}.
26377 @deftypevr {@code{ddclient-configuration} parameter} string user
26378 Specifies the user name or ID that is used when running ddclient
26381 Defaults to @samp{"ddclient"}.
26385 @deftypevr {@code{ddclient-configuration} parameter} string group
26386 Group of the user who will run the ddclient program.
26388 Defaults to @samp{"ddclient"}.
26392 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
26393 Secret file which will be appended to @file{ddclient.conf} file. This
26394 file contains credentials for use by ddclient. You are expected to
26395 create it manually.
26397 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
26401 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
26402 Extra options will be appended to @file{ddclient.conf} file.
26404 Defaults to @samp{()}.
26409 @c %end of fragment
26413 @subsection VPN Services
26414 @cindex VPN (virtual private network)
26415 @cindex virtual private network (VPN)
26417 The @code{(gnu services vpn)} module provides services related to
26418 @dfn{virtual private networks} (VPNs).
26420 @subsubheading OpenVPN
26422 It provides a @emph{client} service for your machine to connect to a
26423 VPN, and a @emph{server} service for your machine to host a VPN@.
26425 @deffn {Scheme Procedure} openvpn-client-service @
26426 [#:config (openvpn-client-configuration)]
26428 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
26431 @deffn {Scheme Procedure} openvpn-server-service @
26432 [#:config (openvpn-server-configuration)]
26434 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
26436 Both can be run simultaneously.
26439 @c %automatically generated documentation
26441 Available @code{openvpn-client-configuration} fields are:
26443 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
26444 The OpenVPN package.
26448 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
26449 The OpenVPN pid file.
26451 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
26455 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
26456 The protocol (UDP or TCP) used to open a channel between clients and
26459 Defaults to @samp{udp}.
26463 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
26464 The device type used to represent the VPN connection.
26466 Defaults to @samp{tun}.
26470 If you do not have some of these files (eg.@: you use a username and
26471 password), you can disable any of the following three fields by setting
26472 it to @code{'disabled}.
26474 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string ca
26475 The certificate authority to check connections against.
26477 Defaults to @samp{"/etc/openvpn/ca.crt"}.
26481 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string cert
26482 The certificate of the machine the daemon is running on. It should be
26483 signed by the authority given in @code{ca}.
26485 Defaults to @samp{"/etc/openvpn/client.crt"}.
26489 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string key
26490 The key of the machine the daemon is running on. It must be the key whose
26491 certificate is @code{cert}.
26493 Defaults to @samp{"/etc/openvpn/client.key"}.
26497 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
26498 Whether to use the lzo compression algorithm.
26500 Defaults to @samp{#t}.
26504 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
26505 Don't re-read key files across SIGUSR1 or --ping-restart.
26507 Defaults to @samp{#t}.
26511 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
26512 Don't close and reopen TUN/TAP device or run up/down scripts across
26513 SIGUSR1 or --ping-restart restarts.
26515 Defaults to @samp{#t}.
26519 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
26520 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
26521 poll/epoll/select prior to the write operation.
26523 Defaults to @samp{#f}.
26526 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
26529 Defaults to @samp{3}.
26533 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
26534 Add an additional layer of HMAC authentication on top of the TLS control
26535 channel to protect against DoS attacks.
26537 Defaults to @samp{#f}.
26541 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
26542 Authenticate with server using username/password. The option is a file
26543 containing username/password on 2 lines. Do not use a file-like object as it
26544 would be added to the store and readable by any user.
26546 Defaults to @samp{'disabled}.
26549 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
26550 Whether to check the server certificate has server usage extension.
26552 Defaults to @samp{#t}.
26556 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
26557 Bind to a specific local port number.
26559 Defaults to @samp{#f}.
26563 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
26564 Retry resolving server address.
26566 Defaults to @samp{#t}.
26570 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
26571 A list of remote servers to connect to.
26573 Defaults to @samp{()}.
26575 Available @code{openvpn-remote-configuration} fields are:
26577 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
26580 Defaults to @samp{"my-server"}.
26584 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
26585 Port number the server listens to.
26587 Defaults to @samp{1194}.
26592 @c %end of automatic openvpn-client documentation
26594 @c %automatically generated documentation
26596 Available @code{openvpn-server-configuration} fields are:
26598 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
26599 The OpenVPN package.
26603 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
26604 The OpenVPN pid file.
26606 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
26610 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
26611 The protocol (UDP or TCP) used to open a channel between clients and
26614 Defaults to @samp{udp}.
26618 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
26619 The device type used to represent the VPN connection.
26621 Defaults to @samp{tun}.
26625 If you do not have some of these files (eg.@: you use a username and
26626 password), you can disable any of the following three fields by setting
26627 it to @code{'disabled}.
26629 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string ca
26630 The certificate authority to check connections against.
26632 Defaults to @samp{"/etc/openvpn/ca.crt"}.
26636 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string cert
26637 The certificate of the machine the daemon is running on. It should be
26638 signed by the authority given in @code{ca}.
26640 Defaults to @samp{"/etc/openvpn/client.crt"}.
26644 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string key
26645 The key of the machine the daemon is running on. It must be the key whose
26646 certificate is @code{cert}.
26648 Defaults to @samp{"/etc/openvpn/client.key"}.
26652 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
26653 Whether to use the lzo compression algorithm.
26655 Defaults to @samp{#t}.
26659 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
26660 Don't re-read key files across SIGUSR1 or --ping-restart.
26662 Defaults to @samp{#t}.
26666 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
26667 Don't close and reopen TUN/TAP device or run up/down scripts across
26668 SIGUSR1 or --ping-restart restarts.
26670 Defaults to @samp{#t}.
26674 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
26675 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
26676 poll/epoll/select prior to the write operation.
26678 Defaults to @samp{#f}.
26681 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
26684 Defaults to @samp{3}.
26688 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
26689 Add an additional layer of HMAC authentication on top of the TLS control
26690 channel to protect against DoS attacks.
26692 Defaults to @samp{#f}.
26696 @deftypevr {@code{openvpn-server-configuration} parameter} number port
26697 Specifies the port number on which the server listens.
26699 Defaults to @samp{1194}.
26703 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
26704 An ip and mask specifying the subnet inside the virtual network.
26706 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
26710 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
26711 A CIDR notation specifying the IPv6 subnet inside the virtual network.
26713 Defaults to @samp{#f}.
26717 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
26718 The Diffie-Hellman parameters file.
26720 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
26724 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
26725 The file that records client IPs.
26727 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
26731 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
26732 When true, the server will act as a gateway for its clients.
26734 Defaults to @samp{#f}.
26738 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
26739 When true, clients are allowed to talk to each other inside the VPN.
26741 Defaults to @samp{#f}.
26745 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
26746 Causes ping-like messages to be sent back and forth over the link so
26747 that each side knows when the other side has gone down. @code{keepalive}
26748 requires a pair. The first element is the period of the ping sending,
26749 and the second element is the timeout before considering the other side
26754 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
26755 The maximum number of clients.
26757 Defaults to @samp{100}.
26761 @deftypevr {@code{openvpn-server-configuration} parameter} string status
26762 The status file. This file shows a small report on current connection.
26763 It is truncated and rewritten every minute.
26765 Defaults to @samp{"/var/run/openvpn/status"}.
26769 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
26770 The list of configuration for some clients.
26772 Defaults to @samp{()}.
26774 Available @code{openvpn-ccd-configuration} fields are:
26776 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
26779 Defaults to @samp{"client"}.
26783 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
26786 Defaults to @samp{#f}.
26790 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
26793 Defaults to @samp{#f}.
26800 @c %end of automatic openvpn-server documentation
26802 @subsubheading Wireguard
26804 @defvr {Scheme Variable} wireguard-service-type
26805 A service type for a Wireguard tunnel interface. Its value must be a
26806 @code{wireguard-configuration} record as in this example:
26809 (service wireguard-service-type
26810 (wireguard-configuration
26815 (endpoint "my.wireguard.com:51820")
26816 (public-key "hzpKg9X1yqu1axN6iJp0mWf6BZGo8m1wteKwtTmDGF4=")
26817 (allowed-ips '("10.0.0.2/32")))))))
26822 @deftp {Data Type} wireguard-configuration
26823 Data type representing the configuration of the Wireguard service.
26826 @item @code{wireguard}
26827 The wireguard package to use for this service.
26829 @item @code{interface} (default: @code{"wg0"})
26830 The interface name for the VPN.
26832 @item @code{addresses} (default: @code{'("10.0.0.1/32")})
26833 The IP addresses to be assigned to the above interface.
26835 @item @code{private-key} (default: @code{"/etc/wireguard/private.key"})
26836 The private key file for the interface. It is automatically generated if
26837 the file does not exist.
26839 @item @code{peers} (default: @code{'()})
26840 The authorized peers on this interface. This is a list of
26841 @var{wireguard-peer} records.
26846 @deftp {Data Type} wireguard-peer
26847 Data type representing a Wireguard peer attached to a given interface.
26853 @item @code{endpoint} (default: @code{#f})
26854 The optional endpoint for the peer, such as
26855 @code{"demo.wireguard.com:51820"}.
26857 @item @code{public-key}
26858 The peer public-key represented as a base64 string.
26860 @item @code{allowed-ips}
26861 A list of IP addresses from which incoming traffic for this peer is
26862 allowed and to which incoming traffic for this peer is directed.
26867 @node Network File System
26868 @subsection Network File System
26871 The @code{(gnu services nfs)} module provides the following services,
26872 which are most commonly used in relation to mounting or exporting
26873 directory trees as @dfn{network file systems} (NFS).
26875 While it is possible to use the individual components that together make
26876 up a Network File System service, we recommended to configure an NFS
26877 server with the @code{nfs-service-type}.
26879 @subsubheading NFS Service
26880 @cindex NFS, server
26882 The NFS service takes care of setting up all NFS component services,
26883 kernel configuration file systems, and installs configuration files in
26884 the locations that NFS expects.
26886 @defvr {Scheme Variable} nfs-service-type
26887 A service type for a complete NFS server.
26890 @deftp {Data Type} nfs-configuration
26891 This data type represents the configuration of the NFS service and all
26894 It has the following parameters:
26896 @item @code{nfs-utils} (default: @code{nfs-utils})
26897 The nfs-utils package to use.
26899 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
26900 If a list of string values is provided, the @command{rpc.nfsd} daemon
26901 will be limited to supporting the given versions of the NFS protocol.
26903 @item @code{exports} (default: @code{'()})
26904 This is a list of directories the NFS server should export. Each entry
26905 is a list consisting of two elements: a directory name and a string
26906 containing all options. This is an example in which the directory
26907 @file{/export} is served to all NFS clients as a read-only share:
26913 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
26916 @item @code{rpcmountd-port} (default: @code{#f})
26917 The network port that the @command{rpc.mountd} daemon should use.
26919 @item @code{rpcstatd-port} (default: @code{#f})
26920 The network port that the @command{rpc.statd} daemon should use.
26922 @item @code{rpcbind} (default: @code{rpcbind})
26923 The rpcbind package to use.
26925 @item @code{idmap-domain} (default: @code{"localdomain"})
26926 The local NFSv4 domain name.
26928 @item @code{nfsd-port} (default: @code{2049})
26929 The network port that the @command{nfsd} daemon should use.
26931 @item @code{nfsd-threads} (default: @code{8})
26932 The number of threads used by the @command{nfsd} daemon.
26934 @item @code{nfsd-tcp?} (default: @code{#t})
26935 Whether the @command{nfsd} daemon should listen on a TCP socket.
26937 @item @code{nfsd-udp?} (default: @code{#f})
26938 Whether the @command{nfsd} daemon should listen on a UDP socket.
26940 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
26941 The directory where the pipefs file system is mounted.
26943 @item @code{debug} (default: @code{'()"})
26944 A list of subsystems for which debugging output should be enabled. This
26945 is a list of symbols. Any of these symbols are valid: @code{nfsd},
26946 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
26950 If you don't need a complete NFS service or prefer to build it yourself
26951 you can use the individual component services that are documented below.
26953 @subsubheading RPC Bind Service
26956 The RPC Bind service provides a facility to map program numbers into
26957 universal addresses.
26958 Many NFS related services use this facility. Hence it is automatically
26959 started when a dependent service starts.
26961 @defvr {Scheme Variable} rpcbind-service-type
26962 A service type for the RPC portmapper daemon.
26966 @deftp {Data Type} rpcbind-configuration
26967 Data type representing the configuration of the RPC Bind Service.
26968 This type has the following parameters:
26970 @item @code{rpcbind} (default: @code{rpcbind})
26971 The rpcbind package to use.
26973 @item @code{warm-start?} (default: @code{#t})
26974 If this parameter is @code{#t}, then the daemon will read a
26975 state file on startup thus reloading state information saved by a previous
26981 @subsubheading Pipefs Pseudo File System
26985 The pipefs file system is used to transfer NFS related data
26986 between the kernel and user space programs.
26988 @defvr {Scheme Variable} pipefs-service-type
26989 A service type for the pipefs pseudo file system.
26992 @deftp {Data Type} pipefs-configuration
26993 Data type representing the configuration of the pipefs pseudo file system service.
26994 This type has the following parameters:
26996 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
26997 The directory to which the file system is to be attached.
27002 @subsubheading GSS Daemon Service
27005 @cindex global security system
27007 The @dfn{global security system} (GSS) daemon provides strong security for RPC
27009 Before exchanging RPC requests an RPC client must establish a security
27010 context. Typically this is done using the Kerberos command @command{kinit}
27011 or automatically at login time using PAM services (@pxref{Kerberos Services}).
27013 @defvr {Scheme Variable} gss-service-type
27014 A service type for the Global Security System (GSS) daemon.
27017 @deftp {Data Type} gss-configuration
27018 Data type representing the configuration of the GSS daemon service.
27019 This type has the following parameters:
27021 @item @code{nfs-utils} (default: @code{nfs-utils})
27022 The package in which the @command{rpc.gssd} command is to be found.
27024 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
27025 The directory where the pipefs file system is mounted.
27031 @subsubheading IDMAP Daemon Service
27033 @cindex name mapper
27035 The idmap daemon service provides mapping between user IDs and user names.
27036 Typically it is required in order to access file systems mounted via NFSv4.
27038 @defvr {Scheme Variable} idmap-service-type
27039 A service type for the Identity Mapper (IDMAP) daemon.
27042 @deftp {Data Type} idmap-configuration
27043 Data type representing the configuration of the IDMAP daemon service.
27044 This type has the following parameters:
27046 @item @code{nfs-utils} (default: @code{nfs-utils})
27047 The package in which the @command{rpc.idmapd} command is to be found.
27049 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
27050 The directory where the pipefs file system is mounted.
27052 @item @code{domain} (default: @code{#f})
27053 The local NFSv4 domain name.
27054 This must be a string or @code{#f}.
27055 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
27057 @item @code{verbosity} (default: @code{0})
27058 The verbosity level of the daemon.
27063 @node Continuous Integration
27064 @subsection Continuous Integration
27066 @cindex continuous integration
27067 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
27068 continuous integration tool for Guix. It can be used both for development and
27069 for providing substitutes to others (@pxref{Substitutes}).
27071 The @code{(gnu services cuirass)} module provides the following service.
27073 @defvr {Scheme Procedure} cuirass-service-type
27074 The type of the Cuirass service. Its value must be a
27075 @code{cuirass-configuration} object, as described below.
27078 To add build jobs, you have to set the @code{specifications} field of the
27079 configuration. Here is an example of a service that polls the Guix repository
27080 and builds the packages from a manifest. Some of the packages are defined in
27081 the @code{"custom-packages"} input, which is the equivalent of
27082 @env{GUIX_PACKAGE_PATH}.
27085 (define %cuirass-specs
27087 '((#:name . "my-manifest")
27088 (#:load-path-inputs . ("guix"))
27089 (#:package-path-inputs . ("custom-packages"))
27090 (#:proc-input . "guix")
27091 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
27092 (#:proc . cuirass-jobs)
27093 (#:proc-args . ((subset . "manifests")
27094 (systems . ("x86_64-linux"))
27095 (manifests . (("config" . "guix/manifest.scm")))))
27096 (#:inputs . (((#:name . "guix")
27097 (#:url . "git://git.savannah.gnu.org/guix.git")
27098 (#:load-path . ".")
27099 (#:branch . "master")
27100 (#:no-compile? . #t))
27101 ((#:name . "config")
27102 (#:url . "https://git.example.org/config.git")
27103 (#:load-path . ".")
27104 (#:branch . "master")
27105 (#:no-compile? . #t))
27106 ((#:name . "custom-packages")
27107 (#:url . "https://git.example.org/custom-packages.git")
27108 (#:load-path . ".")
27109 (#:branch . "master")
27110 (#:no-compile? . #t)))))))
27112 (service cuirass-service-type
27113 (cuirass-configuration
27114 (specifications %cuirass-specs)))
27117 While information related to build jobs is located directly in the
27118 specifications, global settings for the @command{cuirass} process are
27119 accessible in other @code{cuirass-configuration} fields.
27121 @deftp {Data Type} cuirass-configuration
27122 Data type representing the configuration of Cuirass.
27125 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
27126 Location of the log file.
27128 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
27129 Location of the log file used by the web interface.
27131 @item @code{queries-log-file} (default: @code{#f})
27132 Location of the SQL queries log file. By default, SQL queries logging is
27135 @item @code{web-queries-log-file} (default: @code{#f})
27136 Location of the web SQL queries log file. By default, web SQL queries
27137 logging is disabled.
27139 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
27140 Location of the repository cache.
27142 @item @code{user} (default: @code{"cuirass"})
27143 Owner of the @code{cuirass} process.
27145 @item @code{group} (default: @code{"cuirass"})
27146 Owner's group of the @code{cuirass} process.
27148 @item @code{interval} (default: @code{60})
27149 Number of seconds between the poll of the repositories followed by the
27152 @item @code{queue-size} (default: @code{1})
27153 Size of the database writer queue.
27155 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
27156 Location of sqlite database which contains the build results and previously
27157 added specifications.
27159 @item @code{ttl} (default: @code{(* 30 24 3600)})
27160 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
27161 are registered for build results. This means that build results are protected
27162 from garbage collection for at least @var{ttl} seconds.
27164 @item @code{port} (default: @code{8081})
27165 Port number used by the HTTP server.
27167 @item @code{host} (default: @code{"localhost"})
27168 Listen on the network interface for @var{host}. The default is to
27169 accept connections from localhost.
27171 @item @code{specifications} (default: @code{#~'()})
27172 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
27173 where a specification is an association list
27174 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
27175 keys are keywords (@code{#:keyword-example}) as shown in the example
27178 @item @code{use-substitutes?} (default: @code{#f})
27179 This allows using substitutes to avoid building every dependencies of a job
27182 @item @code{one-shot?} (default: @code{#f})
27183 Only evaluate specifications and build derivations once.
27185 @item @code{fallback?} (default: @code{#f})
27186 When substituting a pre-built binary fails, fall back to building
27189 @item @code{extra-options} (default: @code{'()})
27190 Extra options to pass when running the Cuirass processes.
27192 @item @code{cuirass} (default: @code{cuirass})
27193 The Cuirass package to use.
27197 @cindex simple cuirass
27198 @subsubheading Simple Cuirass
27200 The Cuirass service configuration described above can be a little
27201 intimidating. In particular, getting the right @code{specifications}
27202 can prove difficult. The @code{simple-cuirass-configuration->specs}
27203 procedure offers a way to generate those @code{specifications} and thus
27204 setup a continuous integration server more readily.
27206 @deffn {Scheme Procedure} simple-cuirass-configuration->specs @var{configuration}
27207 This procedure takes a @code{simple-cuirass-configuration} record as
27208 argument and returns the corresponding Cuirass specifications gexp.
27211 @deftp {Data Type} simple-cuirass-configuration
27212 Data type representing the configuration of a simple Cuirass instance.
27215 @item @code{build} (default: @code{all})
27216 The packages to be built by Cuirass. It defaults to @code{all}, which
27217 means that all the discovered packages in the subsequent @code{channels}
27218 field are to be selected.
27220 It is also possible to set this field to a list of @code{build-manifest}
27221 records, so that only the packages that are part of the declared
27222 manifests are built. This record is described below.
27224 @deftp {Data Type} build-manifest
27226 @item @code{channel-name}
27227 The name of the channel where the manifest is located.
27229 @item @code{manifest}
27230 The manifest path inside the channel.
27235 @item @code{channels} (default: @code{%default-channels})
27236 The channels to be fetched by Cuirass (@pxref{Channels}).
27238 @item @code{non-package-channels} (default: @code{'()})
27239 List the channel names that must not be searched for packages. That is
27240 often the case for the channel containing the manifest.
27242 @item @code{systems} (default: @code{(list (%current-system))})
27243 Build every discovered package for each system in this list. By default
27244 only the current system is selected.
27249 Here is an example of how to setup a Cuirass instance that builds all
27250 the packages declared by Guix and a user repository. The package list
27251 is re-evaluated each time a commit is pushed in one of the declared
27255 (service cuirass-service-type
27256 (cuirass-configuration
27258 (simple-cuirass-configuration->specs
27259 (simple-cuirass-configuration
27261 (channels (cons (channel
27263 (url "https://my-git-repo/guix.git"))
27264 %default-channels)))))))
27267 In the same spirit, this builds all the packages that are part of the
27268 @code{guix} or @code{my-guix} channels and declared in the manifest
27269 located in the @code{conf} channel.
27272 (service cuirass-service-type
27273 (cuirass-configuration
27275 (simple-cuirass-configuration->specs
27276 (simple-cuirass-configuration
27279 (channel-name 'conf)
27280 (manifest "guix/manifest.scm"))))
27281 (channels (cons* (channel
27283 (url "https://my-git-repo/guix.git"))
27286 (url "https://my-git-repo/conf.git"))
27287 %default-channels))
27288 (non-package-channels '(conf)))))))
27291 Finally, @code{simple-cuirass-services} takes as a second optional
27292 argument a @code{cuirass-configuration} record. It can be used to
27293 customize the configuration of the Cuirass instance.
27296 (simple-cuirass-services
27297 (simple-cuirass-configuration
27299 (channels (cons (channel
27301 (url "https://my-git-repo/guix.git"))
27302 %default-channels))
27303 (non-package-channels '(conf)))
27304 (cuirass-configuration
27305 (inherit %default-cuirass-config)
27306 (host "0.0.0.0"))) ;listen on all interfaces.
27309 @node Power Management Services
27310 @subsection Power Management Services
27313 @cindex power management with TLP
27314 @subsubheading TLP daemon
27316 The @code{(gnu services pm)} module provides a Guix service definition
27317 for the Linux power management tool TLP.
27319 TLP enables various powersaving modes in userspace and kernel.
27320 Contrary to @code{upower-service}, it is not a passive,
27321 monitoring tool, as it will apply custom settings each time a new power
27322 source is detected. More information can be found at
27323 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
27325 @deffn {Scheme Variable} tlp-service-type
27326 The service type for the TLP tool. The default settings are optimised
27327 for battery life on most systems, but you can tweak them to your heart's
27328 content by adding a valid @code{tlp-configuration}:
27330 (service tlp-service-type
27332 (cpu-scaling-governor-on-ac (list "performance"))
27333 (sched-powersave-on-bat? #t)))
27337 Each parameter definition is preceded by its type; for example,
27338 @samp{boolean foo} indicates that the @code{foo} parameter
27339 should be specified as a boolean. Types starting with
27340 @code{maybe-} denote parameters that won't show up in TLP config file
27341 when their value is @code{'disabled}.
27343 @c The following documentation was initially generated by
27344 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
27345 @c documentation is better, so we shouldn't hesitate to edit below as
27346 @c needed. However if the change you want to make to this documentation
27347 @c can be done in an automated way, it's probably easier to change
27348 @c (generate-documentation) than to make it below and have to deal with
27349 @c the churn as TLP updates.
27351 Available @code{tlp-configuration} fields are:
27353 @deftypevr {@code{tlp-configuration} parameter} package tlp
27358 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
27359 Set to true if you wish to enable TLP.
27361 Defaults to @samp{#t}.
27365 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
27366 Default mode when no power supply can be detected. Alternatives are AC
27369 Defaults to @samp{"AC"}.
27373 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
27374 Number of seconds Linux kernel has to wait after the disk goes idle,
27375 before syncing on AC.
27377 Defaults to @samp{0}.
27381 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
27382 Same as @code{disk-idle-ac} but on BAT mode.
27384 Defaults to @samp{2}.
27388 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
27389 Dirty pages flushing periodicity, expressed in seconds.
27391 Defaults to @samp{15}.
27395 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
27396 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
27398 Defaults to @samp{60}.
27402 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
27403 CPU frequency scaling governor on AC mode. With intel_pstate driver,
27404 alternatives are powersave and performance. With acpi-cpufreq driver,
27405 alternatives are ondemand, powersave, performance and conservative.
27407 Defaults to @samp{disabled}.
27411 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
27412 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
27414 Defaults to @samp{disabled}.
27418 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
27419 Set the min available frequency for the scaling governor on AC.
27421 Defaults to @samp{disabled}.
27425 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
27426 Set the max available frequency for the scaling governor on AC.
27428 Defaults to @samp{disabled}.
27432 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
27433 Set the min available frequency for the scaling governor on BAT.
27435 Defaults to @samp{disabled}.
27439 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
27440 Set the max available frequency for the scaling governor on BAT.
27442 Defaults to @samp{disabled}.
27446 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
27447 Limit the min P-state to control the power dissipation of the CPU, in AC
27448 mode. Values are stated as a percentage of the available performance.
27450 Defaults to @samp{disabled}.
27454 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
27455 Limit the max P-state to control the power dissipation of the CPU, in AC
27456 mode. Values are stated as a percentage of the available performance.
27458 Defaults to @samp{disabled}.
27462 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
27463 Same as @code{cpu-min-perf-on-ac} on BAT mode.
27465 Defaults to @samp{disabled}.
27469 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
27470 Same as @code{cpu-max-perf-on-ac} on BAT mode.
27472 Defaults to @samp{disabled}.
27476 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
27477 Enable CPU turbo boost feature on AC mode.
27479 Defaults to @samp{disabled}.
27483 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
27484 Same as @code{cpu-boost-on-ac?} on BAT mode.
27486 Defaults to @samp{disabled}.
27490 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
27491 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
27492 used under light load conditions.
27494 Defaults to @samp{#f}.
27498 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
27499 Same as @code{sched-powersave-on-ac?} but on BAT mode.
27501 Defaults to @samp{#t}.
27505 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
27506 Enable Linux kernel NMI watchdog.
27508 Defaults to @samp{#f}.
27512 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
27513 For Linux kernels with PHC patch applied, change CPU voltages. An
27514 example value would be @samp{"F:V F:V F:V F:V"}.
27516 Defaults to @samp{disabled}.
27520 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
27521 Set CPU performance versus energy saving policy on AC@. Alternatives are
27522 performance, normal, powersave.
27524 Defaults to @samp{"performance"}.
27528 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
27529 Same as @code{energy-perf-policy-ac} but on BAT mode.
27531 Defaults to @samp{"powersave"}.
27535 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
27540 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
27541 Hard disk advanced power management level.
27545 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
27546 Same as @code{disk-apm-bat} but on BAT mode.
27550 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
27551 Hard disk spin down timeout. One value has to be specified for each
27552 declared hard disk.
27554 Defaults to @samp{disabled}.
27558 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
27559 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
27561 Defaults to @samp{disabled}.
27565 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
27566 Select IO scheduler for disk devices. One value has to be specified for
27567 each declared hard disk. Example alternatives are cfq, deadline and
27570 Defaults to @samp{disabled}.
27574 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
27575 SATA aggressive link power management (ALPM) level. Alternatives are
27576 min_power, medium_power, max_performance.
27578 Defaults to @samp{"max_performance"}.
27582 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
27583 Same as @code{sata-linkpwr-ac} but on BAT mode.
27585 Defaults to @samp{"min_power"}.
27589 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
27590 Exclude specified SATA host devices for link power management.
27592 Defaults to @samp{disabled}.
27596 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
27597 Enable Runtime Power Management for AHCI controller and disks on AC
27600 Defaults to @samp{disabled}.
27604 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
27605 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
27607 Defaults to @samp{disabled}.
27611 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
27612 Seconds of inactivity before disk is suspended.
27614 Defaults to @samp{15}.
27618 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
27619 PCI Express Active State Power Management level. Alternatives are
27620 default, performance, powersave.
27622 Defaults to @samp{"performance"}.
27626 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
27627 Same as @code{pcie-aspm-ac} but on BAT mode.
27629 Defaults to @samp{"powersave"}.
27633 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
27634 Radeon graphics clock speed level. Alternatives are low, mid, high,
27637 Defaults to @samp{"high"}.
27641 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
27642 Same as @code{radeon-power-ac} but on BAT mode.
27644 Defaults to @samp{"low"}.
27648 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
27649 Radeon dynamic power management method (DPM). Alternatives are battery,
27652 Defaults to @samp{"performance"}.
27656 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
27657 Same as @code{radeon-dpm-state-ac} but on BAT mode.
27659 Defaults to @samp{"battery"}.
27663 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
27664 Radeon DPM performance level. Alternatives are auto, low, high.
27666 Defaults to @samp{"auto"}.
27670 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
27671 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
27673 Defaults to @samp{"auto"}.
27677 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
27678 Wifi power saving mode.
27680 Defaults to @samp{#f}.
27684 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
27685 Same as @code{wifi-power-ac?} but on BAT mode.
27687 Defaults to @samp{#t}.
27691 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
27692 Disable wake on LAN.
27694 Defaults to @samp{#t}.
27698 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
27699 Timeout duration in seconds before activating audio power saving on
27700 Intel HDA and AC97 devices. A value of 0 disables power saving.
27702 Defaults to @samp{0}.
27706 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
27707 Same as @code{sound-powersave-ac} but on BAT mode.
27709 Defaults to @samp{1}.
27713 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
27714 Disable controller in powersaving mode on Intel HDA devices.
27716 Defaults to @samp{#t}.
27720 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
27721 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
27722 powered on again by releasing (and reinserting) the eject lever or by
27723 pressing the disc eject button on newer models.
27725 Defaults to @samp{#f}.
27729 @deftypevr {@code{tlp-configuration} parameter} string bay-device
27730 Name of the optical drive device to power off.
27732 Defaults to @samp{"sr0"}.
27736 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
27737 Runtime Power Management for PCI(e) bus devices. Alternatives are on
27740 Defaults to @samp{"on"}.
27744 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
27745 Same as @code{runtime-pm-ac} but on BAT mode.
27747 Defaults to @samp{"auto"}.
27751 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
27752 Runtime Power Management for all PCI(e) bus devices, except blacklisted
27755 Defaults to @samp{#t}.
27759 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
27760 Exclude specified PCI(e) device addresses from Runtime Power Management.
27762 Defaults to @samp{disabled}.
27766 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
27767 Exclude PCI(e) devices assigned to the specified drivers from Runtime
27772 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
27773 Enable USB autosuspend feature.
27775 Defaults to @samp{#t}.
27779 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
27780 Exclude specified devices from USB autosuspend.
27782 Defaults to @samp{disabled}.
27786 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
27787 Exclude WWAN devices from USB autosuspend.
27789 Defaults to @samp{#t}.
27793 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
27794 Include specified devices into USB autosuspend, even if they are already
27795 excluded by the driver or via @code{usb-blacklist-wwan?}.
27797 Defaults to @samp{disabled}.
27801 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
27802 Enable USB autosuspend before shutdown.
27804 Defaults to @samp{disabled}.
27808 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
27809 Restore radio device state (bluetooth, wifi, wwan) from previous
27810 shutdown on system startup.
27812 Defaults to @samp{#f}.
27817 @cindex CPU frequency scaling with thermald
27818 @subsubheading Thermald daemon
27820 The @code{(gnu services pm)} module provides an interface to
27821 thermald, a CPU frequency scaling service which helps prevent overheating.
27823 @defvr {Scheme Variable} thermald-service-type
27824 This is the service type for
27825 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
27826 Thermal Daemon, which is responsible for controlling the thermal state
27827 of processors and preventing overheating.
27830 @deftp {Data Type} thermald-configuration
27831 Data type representing the configuration of @code{thermald-service-type}.
27834 @item @code{ignore-cpuid-check?} (default: @code{#f})
27835 Ignore cpuid check for supported CPU models.
27837 @item @code{thermald} (default: @var{thermald})
27838 Package object of thermald.
27843 @node Audio Services
27844 @subsection Audio Services
27846 The @code{(gnu services audio)} module provides a service to start MPD
27847 (the Music Player Daemon).
27850 @subsubheading Music Player Daemon
27852 The Music Player Daemon (MPD) is a service that can play music while
27853 being controlled from the local machine or over the network by a variety
27856 The following example shows how one might run @code{mpd} as user
27857 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
27860 (service mpd-service-type
27866 @defvr {Scheme Variable} mpd-service-type
27867 The service type for @command{mpd}
27870 @deftp {Data Type} mpd-configuration
27871 Data type representing the configuration of @command{mpd}.
27874 @item @code{user} (default: @code{"mpd"})
27875 The user to run mpd as.
27877 @item @code{music-dir} (default: @code{"~/Music"})
27878 The directory to scan for music files.
27880 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
27881 The directory to store playlists.
27883 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
27884 The location of the music database.
27886 @item @code{state-file} (default: @code{"~/.mpd/state"})
27887 The location of the file that stores current MPD's state.
27889 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
27890 The location of the sticker database.
27892 @item @code{port} (default: @code{"6600"})
27893 The port to run mpd on.
27895 @item @code{address} (default: @code{"any"})
27896 The address that mpd will bind to. To use a Unix domain socket,
27897 an absolute path can be specified here.
27899 @item @code{outputs} (default: @code{"(list (mpd-output))"})
27900 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
27905 @deftp {Data Type} mpd-output
27906 Data type representing an @command{mpd} audio output.
27909 @item @code{name} (default: @code{"MPD"})
27910 The name of the audio output.
27912 @item @code{type} (default: @code{"pulse"})
27913 The type of audio output.
27915 @item @code{enabled?} (default: @code{#t})
27916 Specifies whether this audio output is enabled when MPD is started. By
27917 default, all audio outputs are enabled. This is just the default
27918 setting when there is no state file; with a state file, the previous
27921 @item @code{tags?} (default: @code{#t})
27922 If set to @code{#f}, then MPD will not send tags to this output. This
27923 is only useful for output plugins that can receive tags, for example the
27924 @code{httpd} output plugin.
27926 @item @code{always-on?} (default: @code{#f})
27927 If set to @code{#t}, then MPD attempts to keep this audio output always
27928 open. This may be useful for streaming servers, when you don’t want to
27929 disconnect all listeners even when playback is accidentally stopped.
27931 @item @code{mixer-type}
27932 This field accepts a symbol that specifies which mixer should be used
27933 for this audio output: the @code{hardware} mixer, the @code{software}
27934 mixer, the @code{null} mixer (allows setting the volume, but with no
27935 effect; this can be used as a trick to implement an external mixer
27936 External Mixer) or no mixer (@code{none}).
27938 @item @code{extra-options} (default: @code{'()})
27939 An association list of option symbols to string values to be appended to
27940 the audio output configuration.
27945 The following example shows a configuration of @code{mpd} that provides
27946 an HTTP audio streaming output.
27949 (service mpd-service-type
27957 `((encoder . "vorbis")
27958 (port . "8080"))))))))
27962 @node Virtualization Services
27963 @subsection Virtualization Services
27965 The @code{(gnu services virtualization)} module provides services for
27966 the libvirt and virtlog daemons, as well as other virtualization-related
27969 @subsubheading Libvirt daemon
27971 @code{libvirtd} is the server side daemon component of the libvirt
27972 virtualization management system. This daemon runs on host servers
27973 and performs required management tasks for virtualized guests.
27975 @deffn {Scheme Variable} libvirt-service-type
27976 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
27977 Its value must be a @code{libvirt-configuration}.
27980 (service libvirt-service-type
27981 (libvirt-configuration
27982 (unix-sock-group "libvirt")
27983 (tls-port "16555")))
27987 @c Auto-generated with (generate-libvirt-documentation)
27988 Available @code{libvirt-configuration} fields are:
27990 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
27995 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
27996 Flag listening for secure TLS connections on the public TCP/IP port.
27997 You must set @code{listen} for this to have any effect.
27999 It is necessary to setup a CA and issue server certificates before using
28002 Defaults to @samp{#t}.
28006 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
28007 Listen for unencrypted TCP connections on the public TCP/IP port. You must
28008 set @code{listen} for this to have any effect.
28010 Using the TCP socket requires SASL authentication by default. Only SASL
28011 mechanisms which support data encryption are allowed. This is
28012 DIGEST_MD5 and GSSAPI (Kerberos5).
28014 Defaults to @samp{#f}.
28018 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
28019 Port for accepting secure TLS connections. This can be a port number,
28022 Defaults to @samp{"16514"}.
28026 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
28027 Port for accepting insecure TCP connections. This can be a port number,
28030 Defaults to @samp{"16509"}.
28034 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
28035 IP address or hostname used for client connections.
28037 Defaults to @samp{"0.0.0.0"}.
28041 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
28042 Flag toggling mDNS advertisement of the libvirt service.
28044 Alternatively can disable for all services on a host by stopping the
28047 Defaults to @samp{#f}.
28051 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
28052 Default mDNS advertisement name. This must be unique on the immediate
28055 Defaults to @samp{"Virtualization Host <hostname>"}.
28059 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
28060 UNIX domain socket group ownership. This can be used to allow a
28061 'trusted' set of users access to management capabilities without
28064 Defaults to @samp{"root"}.
28068 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
28069 UNIX socket permissions for the R/O socket. This is used for monitoring
28072 Defaults to @samp{"0777"}.
28076 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
28077 UNIX socket permissions for the R/W socket. Default allows only root.
28078 If PolicyKit is enabled on the socket, the default will change to allow
28079 everyone (eg, 0777)
28081 Defaults to @samp{"0770"}.
28085 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
28086 UNIX socket permissions for the admin socket. Default allows only owner
28087 (root), do not change it unless you are sure to whom you are exposing
28090 Defaults to @samp{"0777"}.
28094 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
28095 The directory in which sockets will be found/created.
28097 Defaults to @samp{"/var/run/libvirt"}.
28101 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
28102 Authentication scheme for UNIX read-only sockets. By default socket
28103 permissions allow anyone to connect
28105 Defaults to @samp{"polkit"}.
28109 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
28110 Authentication scheme for UNIX read-write sockets. By default socket
28111 permissions only allow root. If PolicyKit support was compiled into
28112 libvirt, the default will be to use 'polkit' auth.
28114 Defaults to @samp{"polkit"}.
28118 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
28119 Authentication scheme for TCP sockets. If you don't enable SASL, then
28120 all TCP traffic is cleartext. Don't do this outside of a dev/test
28123 Defaults to @samp{"sasl"}.
28127 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
28128 Authentication scheme for TLS sockets. TLS sockets already have
28129 encryption provided by the TLS layer, and limited authentication is done
28132 It is possible to make use of any SASL authentication mechanism as well,
28133 by using 'sasl' for this option
28135 Defaults to @samp{"none"}.
28139 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
28140 API access control scheme.
28142 By default an authenticated user is allowed access to all APIs. Access
28143 drivers can place restrictions on this.
28145 Defaults to @samp{()}.
28149 @deftypevr {@code{libvirt-configuration} parameter} string key-file
28150 Server key file path. If set to an empty string, then no private key is
28153 Defaults to @samp{""}.
28157 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
28158 Server key file path. If set to an empty string, then no certificate is
28161 Defaults to @samp{""}.
28165 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
28166 Server key file path. If set to an empty string, then no CA certificate
28169 Defaults to @samp{""}.
28173 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
28174 Certificate revocation list path. If set to an empty string, then no
28177 Defaults to @samp{""}.
28181 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
28182 Disable verification of our own server certificates.
28184 When libvirtd starts it performs some sanity checks against its own
28187 Defaults to @samp{#f}.
28191 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
28192 Disable verification of client certificates.
28194 Client certificate verification is the primary authentication mechanism.
28195 Any client which does not present a certificate signed by the CA will be
28198 Defaults to @samp{#f}.
28202 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
28203 Whitelist of allowed x509 Distinguished Name.
28205 Defaults to @samp{()}.
28209 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
28210 Whitelist of allowed SASL usernames. The format for username depends on
28211 the SASL authentication mechanism.
28213 Defaults to @samp{()}.
28217 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
28218 Override the compile time default TLS priority string. The default is
28219 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
28220 is desired for libvirt to deviate from the global default settings.
28222 Defaults to @samp{"NORMAL"}.
28226 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
28227 Maximum number of concurrent client connections to allow over all
28230 Defaults to @samp{5000}.
28234 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
28235 Maximum length of queue of connections waiting to be accepted by the
28236 daemon. Note, that some protocols supporting retransmission may obey
28237 this so that a later reattempt at connection succeeds.
28239 Defaults to @samp{1000}.
28243 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
28244 Maximum length of queue of accepted but not yet authenticated clients.
28245 Set this to zero to turn this feature off
28247 Defaults to @samp{20}.
28251 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
28252 Number of workers to start up initially.
28254 Defaults to @samp{5}.
28258 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
28259 Maximum number of worker threads.
28261 If the number of active clients exceeds @code{min-workers}, then more
28262 threads are spawned, up to max_workers limit. Typically you'd want
28263 max_workers to equal maximum number of clients allowed.
28265 Defaults to @samp{20}.
28269 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
28270 Number of priority workers. If all workers from above pool are stuck,
28271 some calls marked as high priority (notably domainDestroy) can be
28272 executed in this pool.
28274 Defaults to @samp{5}.
28278 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
28279 Total global limit on concurrent RPC calls.
28281 Defaults to @samp{20}.
28285 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
28286 Limit on concurrent requests from a single client connection. To avoid
28287 one client monopolizing the server this should be a small fraction of
28288 the global max_requests and max_workers parameter.
28290 Defaults to @samp{5}.
28294 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
28295 Same as @code{min-workers} but for the admin interface.
28297 Defaults to @samp{1}.
28301 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
28302 Same as @code{max-workers} but for the admin interface.
28304 Defaults to @samp{5}.
28308 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
28309 Same as @code{max-clients} but for the admin interface.
28311 Defaults to @samp{5}.
28315 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
28316 Same as @code{max-queued-clients} but for the admin interface.
28318 Defaults to @samp{5}.
28322 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
28323 Same as @code{max-client-requests} but for the admin interface.
28325 Defaults to @samp{5}.
28329 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
28330 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
28332 Defaults to @samp{3}.
28336 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
28339 A filter allows to select a different logging level for a given category
28340 of logs. The format for a filter is one of:
28351 where @code{name} is a string which is matched against the category
28352 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
28353 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
28354 name in the filter can be a substring of the full category name, in
28355 order to match multiple similar categories), the optional @samp{"+"}
28356 prefix tells libvirt to log stack trace for each message matching name,
28357 and @code{x} is the minimal level where matching messages should be
28375 Multiple filters can be defined in a single filters statement, they just
28376 need to be separated by spaces.
28378 Defaults to @samp{"3:remote 4:event"}.
28382 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
28385 An output is one of the places to save logging information. The format
28386 for an output can be:
28390 output goes to stderr
28392 @item x:syslog:name
28393 use syslog for the output and use the given name as the ident
28395 @item x:file:file_path
28396 output to a file, with the given filepath
28399 output to journald logging system
28403 In all case the x prefix is the minimal level, acting as a filter
28420 Multiple outputs can be defined, they just need to be separated by
28423 Defaults to @samp{"3:stderr"}.
28427 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
28428 Allows usage of the auditing subsystem to be altered
28432 0: disable all auditing
28435 1: enable auditing, only if enabled on host
28438 2: enable auditing, and exit if disabled on host.
28442 Defaults to @samp{1}.
28446 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
28447 Send audit messages via libvirt logging infrastructure.
28449 Defaults to @samp{#f}.
28453 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
28454 Host UUID@. UUID must not have all digits be the same.
28456 Defaults to @samp{""}.
28460 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
28461 Source to read host UUID.
28465 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
28468 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
28472 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
28475 Defaults to @samp{"smbios"}.
28479 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
28480 A keepalive message is sent to a client after @code{keepalive_interval}
28481 seconds of inactivity to check if the client is still responding. If
28482 set to -1, libvirtd will never send keepalive requests; however clients
28483 can still send them and the daemon will send responses.
28485 Defaults to @samp{5}.
28489 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
28490 Maximum number of keepalive messages that are allowed to be sent to the
28491 client without getting any response before the connection is considered
28494 In other words, the connection is automatically closed approximately
28495 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
28496 the last message received from the client. When @code{keepalive-count}
28497 is set to 0, connections will be automatically closed after
28498 @code{keepalive-interval} seconds of inactivity without sending any
28499 keepalive messages.
28501 Defaults to @samp{5}.
28505 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
28506 Same as above but for admin interface.
28508 Defaults to @samp{5}.
28512 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
28513 Same as above but for admin interface.
28515 Defaults to @samp{5}.
28519 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
28520 Timeout for Open vSwitch calls.
28522 The @code{ovs-vsctl} utility is used for the configuration and its
28523 timeout option is set by default to 5 seconds to avoid potential
28524 infinite waits blocking libvirt.
28526 Defaults to @samp{5}.
28530 @c %end of autogenerated docs
28532 @subsubheading Virtlog daemon
28533 The virtlogd service is a server side daemon component of libvirt that is
28534 used to manage logs from virtual machine consoles.
28536 This daemon is not used directly by libvirt client applications, rather it
28537 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
28538 standalone daemon, the main @code{libvirtd} daemon can be restarted without
28539 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
28540 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
28542 @deffn {Scheme Variable} virtlog-service-type
28543 This is the type of the virtlog daemon.
28544 Its value must be a @code{virtlog-configuration}.
28547 (service virtlog-service-type
28548 (virtlog-configuration
28549 (max-clients 1000)))
28553 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
28554 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
28556 Defaults to @samp{3}.
28560 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
28563 A filter allows to select a different logging level for a given category
28564 of logs The format for a filter is one of:
28575 where @code{name} is a string which is matched against the category
28576 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
28577 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
28578 be a substring of the full category name, in order to match multiple
28579 similar categories), the optional "+" prefix tells libvirt to log stack
28580 trace for each message matching name, and @code{x} is the minimal level
28581 where matching messages should be logged:
28598 Multiple filters can be defined in a single filters statement, they just
28599 need to be separated by spaces.
28601 Defaults to @samp{"3:remote 4:event"}.
28605 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
28608 An output is one of the places to save logging information The format
28609 for an output can be:
28613 output goes to stderr
28615 @item x:syslog:name
28616 use syslog for the output and use the given name as the ident
28618 @item x:file:file_path
28619 output to a file, with the given filepath
28622 output to journald logging system
28626 In all case the x prefix is the minimal level, acting as a filter
28643 Multiple outputs can be defined, they just need to be separated by
28646 Defaults to @samp{"3:stderr"}.
28650 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
28651 Maximum number of concurrent client connections to allow over all
28654 Defaults to @samp{1024}.
28658 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
28659 Maximum file size before rolling over.
28661 Defaults to @samp{2MB}
28665 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
28666 Maximum number of backup files to keep.
28668 Defaults to @samp{3}
28672 @anchor{transparent-emulation-qemu}
28673 @subsubheading Transparent Emulation with QEMU
28676 @cindex @code{binfmt_misc}
28677 @code{qemu-binfmt-service-type} provides support for transparent
28678 emulation of program binaries built for different architectures---e.g.,
28679 it allows you to transparently execute an ARMv7 program on an x86_64
28680 machine. It achieves this by combining the @uref{https://www.qemu.org,
28681 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
28682 This feature only allows you to emulate GNU/Linux on a different
28683 architecture, but see below for GNU/Hurd support.
28685 @defvr {Scheme Variable} qemu-binfmt-service-type
28686 This is the type of the QEMU/binfmt service for transparent emulation.
28687 Its value must be a @code{qemu-binfmt-configuration} object, which
28688 specifies the QEMU package to use as well as the architecture we want to
28692 (service qemu-binfmt-service-type
28693 (qemu-binfmt-configuration
28694 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
28697 In this example, we enable transparent emulation for the ARM and aarch64
28698 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
28699 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
28700 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
28703 @deftp {Data Type} qemu-binfmt-configuration
28704 This is the configuration for the @code{qemu-binfmt} service.
28707 @item @code{platforms} (default: @code{'()})
28708 The list of emulated QEMU platforms. Each item must be a @dfn{platform
28709 object} as returned by @code{lookup-qemu-platforms} (see below).
28711 For example, let's suppose you're on an x86_64 machine and you have this
28715 (service qemu-binfmt-service-type
28716 (qemu-binfmt-configuration
28717 (platforms (lookup-qemu-platforms "arm"))
28723 guix build -s armhf-linux inkscape
28727 and it will build Inkscape for ARMv7 @emph{as if it were a native
28728 build}, transparently using QEMU to emulate the ARMv7 CPU@. Pretty handy
28729 if you'd like to test a package build for an architecture you don't have
28732 @item @code{qemu} (default: @code{qemu})
28733 The QEMU package to use.
28737 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
28738 Return the list of QEMU platform objects corresponding to
28739 @var{platforms}@dots{}. @var{platforms} must be a list of strings
28740 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
28741 @code{"mips64el"}, and so on.
28744 @deffn {Scheme Procedure} qemu-platform? @var{obj}
28745 Return true if @var{obj} is a platform object.
28748 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
28749 Return the name of @var{platform}---a string such as @code{"arm"}.
28753 @subsubheading The Hurd in a Virtual Machine
28755 @cindex @code{hurd}
28759 Service @code{hurd-vm} provides support for running GNU/Hurd in a
28760 virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
28761 to be used on GNU/Linux and the given GNU/Hurd operating system
28762 configuration is cross-compiled. The virtual machine is a Shepherd
28763 service that can be referred to by the names @code{hurd-vm} and
28764 @code{childhurd} and be controlled with commands such as:
28768 herd stop childhurd
28771 When the service is running, you can view its console by connecting to
28772 it with a VNC client, for example with:
28775 guix environment --ad-hoc tigervnc-client -- \
28776 vncviewer localhost:5900
28779 The default configuration (see @code{hurd-vm-configuration} below)
28780 spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
28781 (the virtual machine emulator) redirects to port 10222 on the host.
28782 Thus, you can connect over SSH to the childhurd with:
28785 ssh root@@localhost -p 10022
28788 The childhurd is volatile and stateless: it starts with a fresh root
28789 file system every time you restart it. By default though, all the files
28790 under @file{/etc/childhurd} on the host are copied as is to the root
28791 file system of the childhurd when it boots. This allows you to
28792 initialize ``secrets'' inside the VM: SSH host keys, authorized
28793 substitute keys, and so on---see the explanation of @code{secret-root}
28796 @defvr {Scheme Variable} hurd-vm-service-type
28797 This is the type of the Hurd in a Virtual Machine service. Its value
28798 must be a @code{hurd-vm-configuration} object, which specifies the
28799 operating system (@pxref{operating-system Reference}) and the disk size
28800 for the Hurd Virtual Machine, the QEMU package to use as well as the
28801 options for running it.
28806 (service hurd-vm-service-type
28807 (hurd-vm-configuration
28808 (disk-size (* 5000 (expt 2 20))) ;5G
28809 (memory-size 1024))) ;1024MiB
28812 would create a disk image big enough to build GNU@tie{}Hello, with some
28816 @deftp {Data Type} hurd-vm-configuration
28817 The data type representing the configuration for
28818 @code{hurd-vm-service-type}.
28821 @item @code{os} (default: @var{%hurd-vm-operating-system})
28822 The operating system to instantiate. This default is bare-bones with a
28823 permissive OpenSSH secure shell daemon listening on port 2222
28824 (@pxref{Networking Services, @code{openssh-service-type}}).
28826 @item @code{qemu} (default: @code{qemu-minimal})
28827 The QEMU package to use.
28829 @item @code{image} (default: @var{hurd-vm-disk-image})
28830 The procedure used to build the disk-image built from this
28833 @item @code{disk-size} (default: @code{'guess})
28834 The size of the disk image.
28836 @item @code{memory-size} (default: @code{512})
28837 The memory size of the Virtual Machine in mebibytes.
28839 @item @code{options} (default: @code{'("--snapshot")})
28840 The extra options for running QEMU.
28842 @item @code{id} (default: @code{#f})
28843 If set, a non-zero positive integer used to parameterize Childhurd
28844 instances. It is appended to the service's name,
28845 e.g. @code{childhurd1}.
28847 @item @code{net-options} (default: @var{hurd-vm-net-options})
28848 The procedure used to produce the list of QEMU networking options.
28850 By default, it produces
28853 '("--device" "rtl8139,netdev=net0"
28854 "--netdev" "user,id=net0\
28855 ,hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004\
28856 ,hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222\
28857 ,hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900")
28860 with forwarded ports:
28863 @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
28864 @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
28865 @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
28868 @item @code{secret-root} (default: @file{/etc/childhurd})
28869 The root directory with out-of-band secrets to be installed into the
28870 childhurd once it runs. Childhurds are volatile which means that on
28871 every startup, secrets such as the SSH host keys and Guix signing key
28874 If the @file{/etc/childhurd} directory does not exist, the
28875 @code{secret-service} running in the Childhurd will be sent an empty
28878 By default, the service automatically populates @file{/etc/childhurd}
28879 with the following non-volatile secrets, unless they already exist:
28882 /etc/childhurd/etc/guix/acl
28883 /etc/childhurd/etc/guix/signing-key.pub
28884 /etc/childhurd/etc/guix/signing-key.sec
28885 /etc/childhurd/etc/ssh/ssh_host_ed25519_key
28886 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
28887 /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
28888 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
28891 These files are automatically sent to the guest Hurd VM when it boots,
28892 including permissions.
28894 @cindex childhurd, offloading
28895 @cindex Hurd, offloading
28896 Having these files in place means that only a couple of things are
28897 missing to allow the host to offload @code{i586-gnu} builds to the
28902 Authorizing the childhurd's key on the host so that the host accepts
28903 build results coming from the childhurd, which can be done like so:
28906 guix archive --authorize < \
28907 /etc/childhurd/etc/guix/signing-key.pub
28911 Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
28915 We're working towards making that happen automatically---get in touch
28916 with us at @email{guix-devel@@gnu.org} to discuss it!
28920 Note that by default the VM image is volatile, i.e., once stopped the
28921 contents are lost. If you want a stateful image instead, override the
28922 configuration's @code{image} and @code{options} without
28923 the @code{--snapshot} flag using something along these lines:
28926 (service hurd-vm-service-type
28927 (hurd-vm-configuration
28928 (image (const "/out/of/store/writable/hurd.img"))
28932 @subsubheading Ganeti
28937 This service is considered experimental. Configuration options may be changed
28938 in a backwards-incompatible manner, and not all features have been thorougly
28939 tested. Users of this service are encouraged to share their experience at
28940 @email{guix-devel@@gnu.org}.
28943 Ganeti is a virtual machine management system. It is designed to keep virtual
28944 machines running on a cluster of servers even in the event of hardware failures,
28945 and to make maintenance and recovery tasks easy. It consists of multiple
28946 services which are described later in this section. In addition to the Ganeti
28947 service, you will need the OpenSSH service (@pxref{Networking Services,
28948 @code{openssh-service-type}}), and update the @file{/etc/hosts} file
28949 (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
28950 and address (or use a DNS server).
28952 All nodes participating in a Ganeti cluster should have the same Ganeti and
28953 @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
28954 cluster node that supports multiple storage backends, and installs the
28955 @code{debootstrap} and @code{guix} @dfn{OS providers}:
28958 (use-package-modules virtualization)
28959 (use-service-modules base ganeti networking ssh)
28962 (host-name "node1")
28963 (hosts-file (plain-file "hosts" (format #f "
28964 127.0.0.1 localhost
28967 192.168.1.200 ganeti.example.com
28968 192.168.1.201 node1.example.com node1
28969 192.168.1.202 node2.example.com node2
28972 ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
28973 ;; in order to use the "plain", "drbd" and "rbd" storage backends.
28974 (packages (append (map specification->package
28975 '("qemu" "lvm2" "drbd-utils" "ceph"
28976 ;; Add the debootstrap and guix OS providers.
28977 "ganeti-instance-guix" "ganeti-instance-debootstrap"))
28980 (append (list (static-networking-service "eth0" "192.168.1.201"
28981 #:netmask "255.255.255.0"
28982 #:gateway "192.168.1.254"
28983 #:name-servers '("192.168.1.252"
28986 ;; Ganeti uses SSH to communicate between nodes.
28987 (service openssh-service-type
28988 (openssh-configuration
28989 (permit-root-login 'without-password)))
28991 (service ganeti-service-type
28992 (ganeti-configuration
28993 ;; This list specifies allowed file system paths
28994 ;; for storing virtual machine images.
28995 (file-storage-paths '("/srv/ganeti/file-storage"))
28996 ;; This variable configures a single "variant" for
28997 ;; both Debootstrap and Guix that works with KVM.
28998 (os %default-ganeti-os))))
29002 Users are advised to read the
29003 @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
29004 administrators guide} to learn about the various cluster options and
29005 day-to-day operations. There is also a
29006 @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
29007 describing how to configure and initialize a small cluster.
29009 @defvr {Scheme Variable} ganeti-service-type
29010 This is a service type that includes all the various services that Ganeti
29013 Its value is a @code{ganeti-configuration} object that defines the package
29014 to use for CLI operations, as well as configuration for the various daemons.
29015 Allowed file storage paths and available guest operating systems are also
29016 configured through this data type.
29019 @deftp {Data Type} ganeti-configuration
29020 The @code{ganeti} service takes the following configuration options:
29023 @item @code{ganeti} (default: @code{ganeti})
29024 The @code{ganeti} package to use. It will be installed to the system profile
29025 and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
29026 that the value specified here does not affect the other services as each refer
29027 to a specific @code{ganeti} package (see below).
29029 @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
29030 @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
29031 @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
29032 @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
29033 @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
29034 @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
29035 @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
29036 @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
29037 @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
29038 @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
29040 These options control the various daemons and cron jobs that are distributed
29041 with Ganeti. The possible values for these are described in detail below.
29042 To override a setting, you must use the configuration type for that service:
29045 (service ganeti-service-type
29046 (ganeti-configuration
29047 (rapi-configuration
29048 (ganeti-rapi-configuration
29049 (interface "eth1"))))
29050 (watcher-configuration
29051 (ganeti-watcher-configuration
29052 (rapi-ip "10.0.0.1"))))
29055 @item @code{file-storage-paths} (default: @code{'()})
29056 List of allowed directories for file storage backend.
29058 @item @code{os} (default: @code{%default-ganeti-os})
29059 List of @code{<ganeti-os>} records.
29062 In essence @code{ganeti-service-type} is shorthand for declaring each service
29066 (service ganeti-noded-service-type)
29067 (service ganeti-confd-service-type)
29068 (service ganeti-wconfd-service-type)
29069 (service ganeti-luxid-service-type)
29070 (service ganeti-kvmd-service-type)
29071 (service ganeti-mond-service-type)
29072 (service ganeti-metad-service-type)
29073 (service ganeti-watcher-service-type)
29074 (service ganeti-cleaner-service-type)
29077 Plus a service extension for @code{etc-service-type} that configures the file
29078 storage backend and OS variants.
29082 @deftp {Data Type} ganeti-os
29083 This data type is suitable for passing to the @code{os} parameter of
29084 @code{ganeti-configuration}. It takes the following parameters:
29088 The name for this OS provider. It is only used to specify where the
29089 configuration ends up. Setting it to ``debootstrap'' will create
29090 @file{/etc/ganeti/instance-debootstrap}.
29092 @item @code{extension}
29093 The file extension for variants of this OS type. For example
29094 @file{.conf} or @file{.scm}.
29096 @item @code{variants} (default: @code{'()})
29097 List of @code{ganeti-os-variant} objects for this OS.
29102 @deftp {Data Type} ganeti-os-variant
29103 This is the data type for a Ganeti OS variant. It takes the following
29108 The name of this variant.
29110 @item @code{configuration}
29111 A configuration file for this variant.
29115 @defvr {Scheme Variable} %default-debootstrap-hooks
29116 This variable contains hooks to configure networking and the GRUB bootloader.
29119 @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
29120 This variable contains a list of packages suitable for a fully-virtualized guest.
29123 @deftp {Data Type} debootstrap-configuration
29125 This data type creates configuration files suitable for the debootstrap OS provider.
29128 @item @code{hooks} (default: @code{%default-debootstrap-hooks})
29129 When not @code{#f}, this must be a G-expression that specifies a directory with
29130 scripts that will run when the OS is installed. It can also be a list of
29131 @code{(name . file-like)} pairs. For example:
29134 `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
29137 That will create a directory with one executable named @code{99-hello-world}
29138 and run it every time this variant is installed. If set to @code{#f}, hooks
29139 in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
29140 @item @code{proxy} (default: @code{#f})
29141 Optional HTTP proxy to use.
29142 @item @code{mirror} (default: @code{#f})
29143 The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
29144 The default varies depending on the distribution.
29145 @item @code{arch} (default: @code{#f})
29146 The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
29147 on an AArch64 host. Default is to use the current system architecture.
29148 @item @code{suite} (default: @code{"stable"})
29149 When set, this must be a Debian distribution ``suite'' such as @code{buster}
29150 or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
29151 @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
29152 List of extra packages that will get installed by dpkg in addition
29153 to the minimal system.
29154 @item @code{components} (default: @code{#f})
29155 When set, must be a list of Debian repository ``components''. For example
29156 @code{'("main" "contrib")}.
29157 @item @code{generate-cache?} (default: @code{#t})
29158 Whether to automatically cache the generated debootstrap archive.
29159 @item @code{clean-cache} (default: @code{14})
29160 Discard the cache after this amount of days. Use @code{#f} to never
29162 @item @code{partition-style} (default: @code{'msdos})
29163 The type of partition to create. When set, it must be one of
29164 @code{'msdos}, @code{'none} or a string.
29165 @item @code{partition-alignment} (default: @code{2048})
29166 Alignment of the partition in sectors.
29170 @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
29171 This is a helper procedure that creates a @code{ganeti-os-variant} record. It
29172 takes two parameters: a name and a @code{debootstrap-configuration} object.
29175 @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
29176 This is a helper procedure that creates a @code{ganeti-os} record. It takes
29177 a list of variants created with @code{debootstrap-variant}.
29180 @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
29181 This is a helper procedure that creates a @code{ganeti-os-variant} record for
29182 use with the Guix OS provider. It takes a name and a G-expression that returns
29183 a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
29184 Guix System configuration.
29187 @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
29188 This is a helper procedure that creates a @code{ganeti-os} record. It
29189 takes a list of variants produced by @code{guix-variant}.
29192 @defvr {Scheme Variable} %default-debootstrap-variants
29193 This is a convenience variable to make the debootstrap provider work
29194 ``out of the box'' without users having to declare variants manually. It
29195 contains a single debootstrap variant with the default configuration:
29198 (list (debootstrap-variant
29200 (debootstrap-configuration)))
29204 @defvr {Scheme Variable} %default-guix-variants
29205 This is a convenience variable to make the Guix OS provider work without
29206 additional configuration. It creates a virtual machine that has an SSH
29207 server, a serial console, and authorizes the Ganeti hosts SSH keys.
29210 (list (guix-variant
29212 (file-append ganeti-instance-guix
29213 "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
29217 Users can implement support for OS providers unbeknownst to Guix by extending
29218 the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
29224 (extension ".conf")
29226 (list (ganeti-os-variant
29228 (configuration (plain-file "bar" "this is fine"))))))
29231 That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
29232 to a file in the store with contents @code{this is fine}. It also creates
29233 @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
29235 Obviously this may not work for all OS providers out there. If you find the
29236 interface limiting, please reach out to @email{guix-devel@@gnu.org}.
29238 The rest of this section documents the various services that are included by
29239 @code{ganeti-service-type}.
29241 @defvr {Scheme Variable} ganeti-noded-service-type
29242 @command{ganeti-noded} is the daemon responsible for node-specific functions
29243 within the Ganeti system. The value of this service must be a
29244 @code{ganeti-noded-configuration} object.
29247 @deftp {Data Type} ganeti-noded-configuration
29248 This is the configuration for the @code{ganeti-noded} service.
29251 @item @code{ganeti} (default: @code{ganeti})
29252 The @code{ganeti} package to use for this service.
29254 @item @code{port} (default: @code{1811})
29255 The TCP port on which the node daemon listens for network requests.
29257 @item @code{address} (default: @code{"0.0.0.0"})
29258 The network address that the daemon will bind to. The default address means
29259 bind to all available addresses.
29261 @item @code{interface} (default: @code{#f})
29262 When this is set, it must be a specific network interface (e.g.@: @code{eth0})
29263 that the daemon will bind to.
29265 @item @code{max-clients} (default: @code{20})
29266 This sets a limit on the maximum number of simultaneous client connections
29267 that the daemon will handle. Connections above this count are accepted, but
29268 no responses will be sent until enough connections have closed.
29270 @item @code{ssl?} (default: @code{#t})
29271 Whether to use SSL/TLS to encrypt network communications. The certificate
29272 is automatically provisioned by the cluster and can be rotated with
29273 @command{gnt-cluster renew-crypto}.
29275 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
29276 This can be used to provide a specific encryption key for TLS communications.
29278 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
29279 This can be used to provide a specific certificate for TLS communications.
29281 @item @code{debug?} (default: @code{#f})
29282 When true, the daemon performs additional logging for debugging purposes.
29283 Note that this will leak encryption details to the log files, use with caution.
29288 @defvr {Scheme Variable} ganeti-confd-service-type
29289 @command{ganeti-confd} answers queries related to the configuration of a
29290 Ganeti cluster. The purpose of this daemon is to have a highly available
29291 and fast way to query cluster configuration values. It is automatically
29292 active on all @dfn{master candidates}. The value of this service must be a
29293 @code{ganeti-confd-configuration} object.
29297 @deftp {Data Type} ganeti-confd-configuration
29298 This is the configuration for the @code{ganeti-confd} service.
29301 @item @code{ganeti} (default: @code{ganeti})
29302 The @code{ganeti} package to use for this service.
29304 @item @code{port} (default: @code{1814})
29305 The UDP port on which to listen for network requests.
29307 @item @code{address} (default: @code{"0.0.0.0"})
29308 Network address that the daemon will bind to.
29310 @item @code{debug?} (default: @code{#f})
29311 When true, the daemon performs additional logging for debugging purposes.
29316 @defvr {Scheme Variable} ganeti-wconfd-service-type
29317 @command{ganeti-wconfd} is the daemon that has authoritative knowledge
29318 about the cluster configuration and is the only entity that can accept
29319 changes to it. All jobs that need to modify the configuration will do so
29320 by sending appropriate requests to this daemon. It only runs on the
29321 @dfn{master node} and will automatically disable itself on other nodes.
29323 The value of this service must be a
29324 @code{ganeti-wconfd-configuration} object.
29327 @deftp {Data Type} ganeti-wconfd-configuration
29328 This is the configuration for the @code{ganeti-wconfd} service.
29331 @item @code{ganeti} (default: @code{ganeti})
29332 The @code{ganeti} package to use for this service.
29334 @item @code{no-voting?} (default: @code{#f})
29335 The daemon will refuse to start if the majority of cluster nodes does not
29336 agree that it is running on the master node. Set to @code{#t} to start
29337 even if a quorum can not be reached (dangerous, use with caution).
29339 @item @code{debug?} (default: @code{#f})
29340 When true, the daemon performs additional logging for debugging purposes.
29345 @defvr {Scheme Variable} ganeti-luxid-service-type
29346 @command{ganeti-luxid} is a daemon used to answer queries related to the
29347 configuration and the current live state of a Ganeti cluster. Additionally,
29348 it is the authoritative daemon for the Ganeti job queue. Jobs can be
29349 submitted via this daemon and it schedules and starts them.
29351 It takes a @code{ganeti-luxid-configuration} object.
29354 @deftp {Data Type} ganeti-luxid-configuration
29355 This is the configuration for the @code{ganeti-wconfd} service.
29358 @item @code{ganeti} (default: @code{ganeti})
29359 The @code{ganeti} package to use for this service.
29361 @item @code{no-voting?} (default: @code{#f})
29362 The daemon will refuse to start if it cannot verify that the majority of
29363 cluster nodes believes that it is running on the master node. Set to
29364 @code{#t} to ignore such checks and start anyway (this can be dangerous).
29366 @item @code{debug?} (default: @code{#f})
29367 When true, the daemon performs additional logging for debugging purposes.
29372 @defvr {Scheme Variable} ganeti-rapi-service-type
29373 @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
29374 the master node and can be used to perform cluster actions programmatically
29375 via a JSON-based RPC protocol.
29377 Most query operations are allowed without authentication (unless
29378 @var{require-authentication?} is set), whereas write operations require
29379 explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
29380 the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
29381 API documentation} for more information.
29383 The value of this service must be a @code{ganeti-rapi-configuration} object.
29386 @deftp {Data Type} ganeti-rapi-configuration
29387 This is the configuration for the @code{ganeti-rapi} service.
29390 @item @code{ganeti} (default: @code{ganeti})
29391 The @code{ganeti} package to use for this service.
29393 @item @code{require-authentication?} (default: @code{#f})
29394 Whether to require authentication even for read-only operations.
29396 @item @code{port} (default: @code{5080})
29397 The TCP port on which to listen to API requests.
29399 @item @code{address} (default: @code{"0.0.0.0"})
29400 The network address that the service will bind to. By default it listens
29401 on all configured addresses.
29403 @item @code{interface} (default: @code{#f})
29404 When set, it must specify a specific network interface such as @code{eth0}
29405 that the daemon will bind to.
29407 @item @code{max-clients} (default: @code{20})
29408 The maximum number of simultaneous client requests to handle. Further
29409 connections are allowed, but no responses are sent until enough connections
29412 @item @code{ssl?} (default: @code{#t})
29413 Whether to use SSL/TLS encryption on the RAPI port.
29415 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
29416 This can be used to provide a specific encryption key for TLS communications.
29418 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
29419 This can be used to provide a specific certificate for TLS communications.
29421 @item @code{debug?} (default: @code{#f})
29422 When true, the daemon performs additional logging for debugging purposes.
29423 Note that this will leak encryption details to the log files, use with caution.
29428 @defvr {Scheme Variable} ganeti-kvmd-service-type
29429 @command{ganeti-kvmd} is responsible for determining whether a given KVM
29430 instance was shut down by an administrator or a user. Normally Ganeti will
29431 restart an instance that was not stopped through Ganeti itself. If the
29432 cluster option @code{user_shutdown} is true, this daemon monitors the
29433 @code{QMP} socket provided by QEMU and listens for shutdown events, and
29434 marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
29435 it shuts down gracefully by itself.
29437 It takes a @code{ganeti-kvmd-configuration} object.
29440 @deftp {Data Type} ganeti-kvmd-configuration
29443 @item @code{ganeti} (default: @code{ganeti})
29444 The @code{ganeti} package to use for this service.
29446 @item @code{debug?} (default: @code{#f})
29447 When true, the daemon performs additional logging for debugging purposes.
29452 @defvr {Scheme Variable} ganeti-mond-service-type
29453 @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
29454 functionality. It is responsible for running data collectors and publish the
29455 collected information through a HTTP interface.
29457 It takes a @code{ganeti-mond-configuration} object.
29460 @deftp {Data Type} ganeti-mond-configuration
29463 @item @code{ganeti} (default: @code{ganeti})
29464 The @code{ganeti} package to use for this service.
29466 @item @code{port} (default: @code{1815})
29467 The port on which the daemon will listen.
29469 @item @code{address} (default: @code{"0.0.0.0"})
29470 The network address that the daemon will bind to. By default it binds to all
29471 available interfaces.
29473 @item @code{debug?} (default: @code{#f})
29474 When true, the daemon performs additional logging for debugging purposes.
29479 @defvr {Scheme Variable} ganeti-metad-service-type
29480 @command{ganeti-metad} is an optional daemon that can be used to provide
29481 information about the cluster to instances or OS install scripts.
29483 It takes a @code{ganeti-metad-configuration} object.
29486 @deftp {Data Type} ganeti-metad-configuration
29489 @item @code{ganeti} (default: @code{ganeti})
29490 The @code{ganeti} package to use for this service.
29492 @item @code{port} (default: @code{80})
29493 The port on which the daemon will listen.
29495 @item @code{address} (default: @code{#f})
29496 If set, the daemon will bind to this address only. If left unset, the behavior
29497 depends on the cluster configuration.
29499 @item @code{debug?} (default: @code{#f})
29500 When true, the daemon performs additional logging for debugging purposes.
29505 @defvr {Scheme Variable} ganeti-watcher-service-type
29506 @command{ganeti-watcher} is a script designed to run periodically and ensure
29507 the health of a cluster. It will automatically restart instances that have
29508 stopped without Ganeti's consent, and repairs DRBD links in case a node has
29509 rebooted. It also archives old cluster jobs and restarts Ganeti daemons
29510 that are not running. If the cluster parameter @code{ensure_node_health}
29511 is set, the watcher will also shutdown instances and DRBD devices if the
29512 node it is running on is declared offline by known master candidates.
29514 It can be paused on all nodes with @command{gnt-cluster watcher pause}.
29516 The service takes a @code{ganeti-watcher-configuration} object.
29519 @deftp {Data Type} ganeti-watcher-configuration
29522 @item @code{ganeti} (default: @code{ganeti})
29523 The @code{ganeti} package to use for this service.
29525 @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
29526 How often to run the script. The default is every five minutes.
29528 @item @code{rapi-ip} (default: @code{#f})
29529 This option needs to be specified only if the RAPI daemon is configured to use
29530 a particular interface or address. By default the cluster address is used.
29532 @item @code{job-age} (default: @code{(* 6 3600)})
29533 Archive cluster jobs older than this age, specified in seconds. The default
29534 is 6 hours. This keeps @command{gnt-job list} manageable.
29536 @item @code{verify-disks?} (default: @code{#t})
29537 If this is @code{#f}, the watcher will not try to repair broken DRBD links
29538 automatically. Administrators will need to use @command{gnt-cluster verify-disks}
29541 @item @code{debug?} (default: @code{#f})
29542 When @code{#t}, the script performs additional logging for debugging purposes.
29547 @defvr {Scheme Variable} ganeti-cleaner-service-type
29548 @command{ganeti-cleaner} is a script designed to run periodically and remove
29549 old files from the cluster. This service type controls two @dfn{cron jobs}:
29550 one intended for the master node that permanently purges old cluster jobs,
29551 and one intended for every node that removes expired X509 certificates, keys,
29552 and outdated @command{ganeti-watcher} information. Like all Ganeti services,
29553 it is safe to include even on non-master nodes as it will disable itself as
29556 It takes a @code{ganeti-cleaner-configuration} object.
29559 @deftp {Data Type} ganeti-cleaner-configuration
29562 @item @code{ganeti} (default: @code{ganeti})
29563 The @code{ganeti} package to use for the @command{gnt-cleaner} command.
29565 @item @code{master-schedule} (default: @code{"45 1 * * *"})
29566 How often to run the master cleaning job. The default is once per day, at
29569 @item @code{node-schedule} (default: @code{"45 2 * * *"})
29570 How often to run the node cleaning job. The default is once per day, at
29576 @node Version Control Services
29577 @subsection Version Control Services
29579 The @code{(gnu services version-control)} module provides a service to
29580 allow remote access to local Git repositories. There are three options:
29581 the @code{git-daemon-service}, which provides access to repositories via
29582 the @code{git://} unsecured TCP-based protocol, extending the
29583 @code{nginx} web server to proxy some requests to
29584 @code{git-http-backend}, or providing a web interface with
29585 @code{cgit-service-type}.
29587 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
29589 Return a service that runs @command{git daemon}, a simple TCP server to
29590 expose repositories over the Git protocol for anonymous access.
29592 The optional @var{config} argument should be a
29593 @code{<git-daemon-configuration>} object, by default it allows read-only
29594 access to exported@footnote{By creating the magic file
29595 @file{git-daemon-export-ok} in the repository directory.} repositories under
29600 @deftp {Data Type} git-daemon-configuration
29601 Data type representing the configuration for @code{git-daemon-service}.
29604 @item @code{package} (default: @code{git})
29605 Package object of the Git distributed version control system.
29607 @item @code{export-all?} (default: @code{#f})
29608 Whether to allow access for all Git repositories, even if they do not
29609 have the @file{git-daemon-export-ok} file.
29611 @item @code{base-path} (default: @file{/srv/git})
29612 Whether to remap all the path requests as relative to the given path.
29613 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
29614 @samp{example.com}, then if you later try to pull
29615 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
29616 path as @file{/srv/git/hello.git}.
29618 @item @code{user-path} (default: @code{#f})
29619 Whether to allow @code{~user} notation to be used in requests. When
29620 specified with empty string, requests to
29621 @indicateurl{git://host/~alice/foo} is taken as a request to access
29622 @code{foo} repository in the home directory of user @code{alice}. If
29623 @code{(user-path "@var{path}")} is specified, the same request is taken
29624 as a request to access @file{@var{path}/foo} repository in the home
29625 directory of user @code{alice}.
29627 @item @code{listen} (default: @code{'()})
29628 Whether to listen on specific IP addresses or hostnames, defaults to
29631 @item @code{port} (default: @code{#f})
29632 Whether to listen on an alternative port, which defaults to 9418.
29634 @item @code{whitelist} (default: @code{'()})
29635 If not empty, only allow access to this list of directories.
29637 @item @code{extra-options} (default: @code{'()})
29638 Extra options will be passed to @command{git daemon}, please run
29639 @command{man git-daemon} for more information.
29644 The @code{git://} protocol lacks authentication. When you pull from a
29645 repository fetched via @code{git://}, you don't know whether the data you
29646 receive was modified or is even coming from the specified host, and your
29647 connection is subject to eavesdropping. It's better to use an authenticated
29648 and encrypted transport, such as @code{https}. Although Git allows you
29649 to serve repositories using unsophisticated file-based web servers,
29650 there is a faster protocol implemented by the @code{git-http-backend}
29651 program. This program is the back-end of a proper Git web service. It
29652 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
29653 on running the necessary @code{fcgiwrap} daemon.
29655 Guix has a separate configuration data type for serving Git repositories
29658 @deftp {Data Type} git-http-configuration
29659 Data type representing the configuration for a future
29660 @code{git-http-service-type}; can currently be used to configure Nginx
29661 through @code{git-http-nginx-location-configuration}.
29664 @item @code{package} (default: @var{git})
29665 Package object of the Git distributed version control system.
29667 @item @code{git-root} (default: @file{/srv/git})
29668 Directory containing the Git repositories to expose to the world.
29670 @item @code{export-all?} (default: @code{#f})
29671 Whether to expose access for all Git repositories in @var{git-root},
29672 even if they do not have the @file{git-daemon-export-ok} file.
29674 @item @code{uri-path} (default: @samp{/git/})
29675 Path prefix for Git access. With the default @samp{/git/} prefix, this
29676 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
29677 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
29678 with this prefix are not passed on to this Git instance.
29680 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
29681 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
29686 There is no @code{git-http-service-type}, currently; instead you can
29687 create an @code{nginx-location-configuration} from a
29688 @code{git-http-configuration} and then add that location to a web
29691 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
29692 [config=(git-http-configuration)]
29693 Compute an @code{nginx-location-configuration} that corresponds to the
29694 given Git http configuration. An example nginx service definition to
29695 serve the default @file{/srv/git} over HTTPS might be:
29698 (service nginx-service-type
29699 (nginx-configuration
29702 (nginx-server-configuration
29703 (listen '("443 ssl"))
29704 (server-name "git.my-host.org")
29706 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
29707 (ssl-certificate-key
29708 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
29711 (git-http-nginx-location-configuration
29712 (git-http-configuration (uri-path "/"))))))))))
29715 This example assumes that you are using Let's Encrypt to get your TLS
29716 certificate. @xref{Certificate Services}. The default @code{certbot}
29717 service will redirect all HTTP traffic on @code{git.my-host.org} to
29718 HTTPS@. You will also need to add an @code{fcgiwrap} proxy to your
29719 system services. @xref{Web Services}.
29722 @subsubheading Cgit Service
29724 @cindex Cgit service
29725 @cindex Git, web interface
29726 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
29727 repositories written in C.
29729 The following example will configure the service with default values.
29730 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
29733 (service cgit-service-type)
29736 The @code{file-object} type designates either a file-like object
29737 (@pxref{G-Expressions, file-like objects}) or a string.
29739 @c %start of fragment
29741 Available @code{cgit-configuration} fields are:
29743 @deftypevr {@code{cgit-configuration} parameter} package package
29748 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
29749 NGINX configuration.
29753 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
29754 Specifies a command which will be invoked to format the content of about
29755 pages (both top-level and for each repository).
29757 Defaults to @samp{""}.
29761 @deftypevr {@code{cgit-configuration} parameter} string agefile
29762 Specifies a path, relative to each repository path, which can be used to
29763 specify the date and time of the youngest commit in the repository.
29765 Defaults to @samp{""}.
29769 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
29770 Specifies a command that will be invoked for authenticating repository
29773 Defaults to @samp{""}.
29777 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
29778 Flag which, when set to @samp{age}, enables date ordering in the branch
29779 ref list, and when set @samp{name} enables ordering by branch name.
29781 Defaults to @samp{"name"}.
29785 @deftypevr {@code{cgit-configuration} parameter} string cache-root
29786 Path used to store the cgit cache entries.
29788 Defaults to @samp{"/var/cache/cgit"}.
29792 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
29793 Number which specifies the time-to-live, in minutes, for the cached
29794 version of repository pages accessed with a fixed SHA1.
29796 Defaults to @samp{-1}.
29800 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
29801 Number which specifies the time-to-live, in minutes, for the cached
29802 version of repository pages accessed without a fixed SHA1.
29804 Defaults to @samp{5}.
29808 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
29809 Number which specifies the time-to-live, in minutes, for the cached
29810 version of the repository summary page.
29812 Defaults to @samp{5}.
29816 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
29817 Number which specifies the time-to-live, in minutes, for the cached
29818 version of the repository index page.
29820 Defaults to @samp{5}.
29824 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
29825 Number which specifies the time-to-live, in minutes, for the result of
29826 scanning a path for Git repositories.
29828 Defaults to @samp{15}.
29832 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
29833 Number which specifies the time-to-live, in minutes, for the cached
29834 version of the repository about page.
29836 Defaults to @samp{15}.
29840 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
29841 Number which specifies the time-to-live, in minutes, for the cached
29842 version of snapshots.
29844 Defaults to @samp{5}.
29848 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
29849 The maximum number of entries in the cgit cache. When set to @samp{0},
29850 caching is disabled.
29852 Defaults to @samp{0}.
29856 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
29857 Sort items in the repo list case sensitively.
29859 Defaults to @samp{#t}.
29863 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
29864 List of common prefixes which, when combined with a repository URL,
29865 generates valid clone URLs for the repository.
29867 Defaults to @samp{()}.
29871 @deftypevr {@code{cgit-configuration} parameter} list clone-url
29872 List of @code{clone-url} templates.
29874 Defaults to @samp{()}.
29878 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
29879 Command which will be invoked to format commit messages.
29881 Defaults to @samp{""}.
29885 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
29886 Flag which, when set to @samp{date}, enables strict date ordering in the
29887 commit log, and when set to @samp{topo} enables strict topological
29890 Defaults to @samp{"git log"}.
29894 @deftypevr {@code{cgit-configuration} parameter} file-object css
29895 URL which specifies the css document to include in all cgit pages.
29897 Defaults to @samp{"/share/cgit/cgit.css"}.
29901 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
29902 Specifies a command which will be invoked to format names and email
29903 address of committers, authors, and taggers, as represented in various
29904 places throughout the cgit interface.
29906 Defaults to @samp{""}.
29910 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
29911 Flag which, when set to @samp{#t}, will make cgit generate a HTML
29912 fragment suitable for embedding in other HTML pages.
29914 Defaults to @samp{#f}.
29918 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
29919 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
29920 commit history graph to the left of the commit messages in the
29921 repository log page.
29923 Defaults to @samp{#f}.
29927 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
29928 Flag which, when set to @samp{#t}, allows all filter settings to be
29929 overridden in repository-specific cgitrc files.
29931 Defaults to @samp{#f}.
29935 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
29936 Flag which, when set to @samp{#t}, allows users to follow a file in the
29939 Defaults to @samp{#f}.
29943 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
29944 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
29947 Defaults to @samp{#t}.
29951 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
29952 Flag which, when set to @samp{#t}, will make cgit generate extra links
29953 "summary", "commit", "tree" for each repo in the repository index.
29955 Defaults to @samp{#f}.
29959 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
29960 Flag which, when set to @samp{#t}, will make cgit display the owner of
29961 each repo in the repository index.
29963 Defaults to @samp{#t}.
29967 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
29968 Flag which, when set to @samp{#t}, will make cgit print the number of
29969 modified files for each commit on the repository log page.
29971 Defaults to @samp{#f}.
29975 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
29976 Flag which, when set to @samp{#t}, will make cgit print the number of
29977 added and removed lines for each commit on the repository log page.
29979 Defaults to @samp{#f}.
29983 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
29984 Flag which, when set to @code{#t}, will make cgit display remote
29985 branches in the summary and refs views.
29987 Defaults to @samp{#f}.
29991 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
29992 Flag which, when set to @code{1}, will make cgit use the subject of the
29993 parent commit as link text when generating links to parent commits in
29996 Defaults to @samp{#f}.
30000 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
30001 Flag which, when set to @samp{#t}, will make cgit use the subject of the
30002 parent commit as link text when generating links to parent commits in
30005 Defaults to @samp{#f}.
30009 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
30010 Flag which, when set to @samp{#t}, will make cgit generate linenumber
30011 links for plaintext blobs printed in the tree view.
30013 Defaults to @samp{#t}.
30017 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
30018 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
30019 set any repo specific settings.
30021 Defaults to @samp{#f}.
30025 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
30026 URL used as link to a shortcut icon for cgit.
30028 Defaults to @samp{"/favicon.ico"}.
30032 @deftypevr {@code{cgit-configuration} parameter} string footer
30033 The content of the file specified with this option will be included
30034 verbatim at the bottom of all pages (i.e.@: it replaces the standard
30035 "generated by..."@: message).
30037 Defaults to @samp{""}.
30041 @deftypevr {@code{cgit-configuration} parameter} string head-include
30042 The content of the file specified with this option will be included
30043 verbatim in the HTML HEAD section on all pages.
30045 Defaults to @samp{""}.
30049 @deftypevr {@code{cgit-configuration} parameter} string header
30050 The content of the file specified with this option will be included
30051 verbatim at the top of all pages.
30053 Defaults to @samp{""}.
30057 @deftypevr {@code{cgit-configuration} parameter} file-object include
30058 Name of a configfile to include before the rest of the current config-
30061 Defaults to @samp{""}.
30065 @deftypevr {@code{cgit-configuration} parameter} string index-header
30066 The content of the file specified with this option will be included
30067 verbatim above the repository index.
30069 Defaults to @samp{""}.
30073 @deftypevr {@code{cgit-configuration} parameter} string index-info
30074 The content of the file specified with this option will be included
30075 verbatim below the heading on the repository index page.
30077 Defaults to @samp{""}.
30081 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
30082 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
30083 in the servers timezone.
30085 Defaults to @samp{#f}.
30089 @deftypevr {@code{cgit-configuration} parameter} file-object logo
30090 URL which specifies the source of an image which will be used as a logo
30093 Defaults to @samp{"/share/cgit/cgit.png"}.
30097 @deftypevr {@code{cgit-configuration} parameter} string logo-link
30098 URL loaded when clicking on the cgit logo image.
30100 Defaults to @samp{""}.
30104 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
30105 Command which will be invoked to format the Owner column of the main
30108 Defaults to @samp{""}.
30112 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
30113 Number of items to display in atom feeds view.
30115 Defaults to @samp{10}.
30119 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
30120 Number of entries to list per page in "log" view.
30122 Defaults to @samp{50}.
30126 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
30127 Number of commit message characters to display in "log" view.
30129 Defaults to @samp{80}.
30133 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
30134 Specifies the number of entries to list per page on the repository index
30137 Defaults to @samp{50}.
30141 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
30142 Specifies the maximum number of repo description characters to display
30143 on the repository index page.
30145 Defaults to @samp{80}.
30149 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
30150 Specifies the maximum size of a blob to display HTML for in KBytes.
30152 Defaults to @samp{0}.
30156 @deftypevr {@code{cgit-configuration} parameter} string max-stats
30157 Maximum statistics period. Valid values are @samp{week},@samp{month},
30158 @samp{quarter} and @samp{year}.
30160 Defaults to @samp{""}.
30164 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
30165 Mimetype for the specified filename extension.
30167 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
30168 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
30169 "image/png") (svg "image/svg+xml"))}.
30173 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
30174 Specifies the file to use for automatic mimetype lookup.
30176 Defaults to @samp{""}.
30180 @deftypevr {@code{cgit-configuration} parameter} string module-link
30181 Text which will be used as the formatstring for a hyperlink when a
30182 submodule is printed in a directory listing.
30184 Defaults to @samp{""}.
30188 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
30189 If set to the value @samp{#t} caching will be disabled.
30191 Defaults to @samp{#f}.
30195 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
30196 If set to @samp{#t} showing full author email addresses will be
30199 Defaults to @samp{#f}.
30203 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
30204 Flag which, when set to @samp{#t}, will make cgit omit the standard
30205 header on all pages.
30207 Defaults to @samp{#f}.
30211 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
30212 A list of subdirectories inside of @code{repository-directory}, relative
30213 to it, that should loaded as Git repositories. An empty list means that
30214 all subdirectories will be loaded.
30216 Defaults to @samp{()}.
30220 @deftypevr {@code{cgit-configuration} parameter} file-object readme
30221 Text which will be used as default value for @code{cgit-repo-readme}.
30223 Defaults to @samp{""}.
30227 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
30228 If set to @code{#t} and @code{repository-directory} is enabled, if any
30229 repositories are found with a suffix of @code{.git}, this suffix will be
30230 removed for the URL and name.
30232 Defaults to @samp{#f}.
30236 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
30237 Maximum number of files to consider when detecting renames.
30239 Defaults to @samp{-1}.
30243 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
30244 The way in which repositories in each section are sorted.
30246 Defaults to @samp{""}.
30250 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
30251 Text used as content for the @code{robots} meta-tag.
30253 Defaults to @samp{("noindex" "nofollow")}.
30257 @deftypevr {@code{cgit-configuration} parameter} string root-desc
30258 Text printed below the heading on the repository index page.
30260 Defaults to @samp{"a fast webinterface for the git dscm"}.
30264 @deftypevr {@code{cgit-configuration} parameter} string root-readme
30265 The content of the file specified with this option will be included
30266 verbatim below the ``about'' link on the repository index page.
30268 Defaults to @samp{""}.
30272 @deftypevr {@code{cgit-configuration} parameter} string root-title
30273 Text printed as heading on the repository index page.
30275 Defaults to @samp{""}.
30279 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
30280 If set to @samp{#t} and repository-directory is enabled,
30281 repository-directory will recurse into directories whose name starts
30282 with a period. Otherwise, repository-directory will stay away from such
30283 directories, considered as ``hidden''. Note that this does not apply to
30284 the @file{.git} directory in non-bare repos.
30286 Defaults to @samp{#f}.
30290 @deftypevr {@code{cgit-configuration} parameter} list snapshots
30291 Text which specifies the default set of snapshot formats that cgit
30292 generates links for.
30294 Defaults to @samp{()}.
30298 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
30299 Name of the directory to scan for repositories (represents
30302 Defaults to @samp{"/srv/git"}.
30306 @deftypevr {@code{cgit-configuration} parameter} string section
30307 The name of the current repository section - all repositories defined
30308 after this option will inherit the current section name.
30310 Defaults to @samp{""}.
30314 @deftypevr {@code{cgit-configuration} parameter} string section-sort
30315 Flag which, when set to @samp{1}, will sort the sections on the
30316 repository listing by name.
30318 Defaults to @samp{""}.
30322 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
30323 A number which, if defined prior to repository-directory, specifies how
30324 many path elements from each repo path to use as a default section name.
30326 Defaults to @samp{0}.
30330 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
30331 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
30334 Defaults to @samp{#f}.
30338 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
30339 Specifies a command which will be invoked to format plaintext blobs in
30342 Defaults to @samp{""}.
30346 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
30347 Specifies the number of branches to display in the repository ``summary''
30350 Defaults to @samp{10}.
30354 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
30355 Specifies the number of log entries to display in the repository
30358 Defaults to @samp{10}.
30362 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
30363 Specifies the number of tags to display in the repository ``summary''
30366 Defaults to @samp{10}.
30370 @deftypevr {@code{cgit-configuration} parameter} string strict-export
30371 Filename which, if specified, needs to be present within the repository
30372 for cgit to allow access to that repository.
30374 Defaults to @samp{""}.
30378 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
30379 URL which, if specified, will be used as root for all cgit links.
30381 Defaults to @samp{"/"}.
30385 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
30386 A list of @dfn{cgit-repo} records to use with config.
30388 Defaults to @samp{()}.
30390 Available @code{repository-cgit-configuration} fields are:
30392 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
30393 A mask of snapshot formats for this repo that cgit generates links for,
30394 restricted by the global @code{snapshots} setting.
30396 Defaults to @samp{()}.
30400 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
30401 Override the default @code{source-filter}.
30403 Defaults to @samp{""}.
30407 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
30408 The relative URL used to access the repository.
30410 Defaults to @samp{""}.
30414 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
30415 Override the default @code{about-filter}.
30417 Defaults to @samp{""}.
30421 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
30422 Flag which, when set to @samp{age}, enables date ordering in the branch
30423 ref list, and when set to @samp{name} enables ordering by branch name.
30425 Defaults to @samp{""}.
30429 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
30430 A list of URLs which can be used to clone repo.
30432 Defaults to @samp{()}.
30436 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
30437 Override the default @code{commit-filter}.
30439 Defaults to @samp{""}.
30443 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
30444 Flag which, when set to @samp{date}, enables strict date ordering in the
30445 commit log, and when set to @samp{topo} enables strict topological
30448 Defaults to @samp{""}.
30452 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
30453 The name of the default branch for this repository. If no such branch
30454 exists in the repository, the first branch name (when sorted) is used as
30455 default instead. By default branch pointed to by HEAD, or ``master'' if
30456 there is no suitable HEAD.
30458 Defaults to @samp{""}.
30462 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
30463 The value to show as repository description.
30465 Defaults to @samp{""}.
30469 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
30470 The value to show as repository homepage.
30472 Defaults to @samp{""}.
30476 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
30477 Override the default @code{email-filter}.
30479 Defaults to @samp{""}.
30483 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
30484 A flag which can be used to disable the global setting
30485 @code{enable-commit-graph?}.
30487 Defaults to @samp{disabled}.
30491 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
30492 A flag which can be used to disable the global setting
30493 @code{enable-log-filecount?}.
30495 Defaults to @samp{disabled}.
30499 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
30500 A flag which can be used to disable the global setting
30501 @code{enable-log-linecount?}.
30503 Defaults to @samp{disabled}.
30507 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
30508 Flag which, when set to @code{#t}, will make cgit display remote
30509 branches in the summary and refs views.
30511 Defaults to @samp{disabled}.
30515 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
30516 A flag which can be used to override the global setting
30517 @code{enable-subject-links?}.
30519 Defaults to @samp{disabled}.
30523 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
30524 A flag which can be used to override the global setting
30525 @code{enable-html-serving?}.
30527 Defaults to @samp{disabled}.
30531 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
30532 Flag which, when set to @code{#t}, hides the repository from the
30535 Defaults to @samp{#f}.
30539 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
30540 Flag which, when set to @samp{#t}, ignores the repository.
30542 Defaults to @samp{#f}.
30546 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
30547 URL which specifies the source of an image which will be used as a logo
30548 on this repo’s pages.
30550 Defaults to @samp{""}.
30554 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
30555 URL loaded when clicking on the cgit logo image.
30557 Defaults to @samp{""}.
30561 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
30562 Override the default @code{owner-filter}.
30564 Defaults to @samp{""}.
30568 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
30569 Text which will be used as the formatstring for a hyperlink when a
30570 submodule is printed in a directory listing. The arguments for the
30571 formatstring are the path and SHA1 of the submodule commit.
30573 Defaults to @samp{""}.
30577 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
30578 Text which will be used as the formatstring for a hyperlink when a
30579 submodule with the specified subdirectory path is printed in a directory
30582 Defaults to @samp{()}.
30586 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
30587 Override the default maximum statistics period.
30589 Defaults to @samp{""}.
30593 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
30594 The value to show as repository name.
30596 Defaults to @samp{""}.
30600 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
30601 A value used to identify the owner of the repository.
30603 Defaults to @samp{""}.
30607 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
30608 An absolute path to the repository directory.
30610 Defaults to @samp{""}.
30614 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
30615 A path (relative to repo) which specifies a file to include verbatim as
30616 the ``About'' page for this repo.
30618 Defaults to @samp{""}.
30622 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
30623 The name of the current repository section - all repositories defined
30624 after this option will inherit the current section name.
30626 Defaults to @samp{""}.
30630 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
30631 Extra options will be appended to cgitrc file.
30633 Defaults to @samp{()}.
30639 @deftypevr {@code{cgit-configuration} parameter} list extra-options
30640 Extra options will be appended to cgitrc file.
30642 Defaults to @samp{()}.
30647 @c %end of fragment
30649 However, it could be that you just want to get a @code{cgitrc} up and
30650 running. In that case, you can pass an @code{opaque-cgit-configuration}
30651 as a record to @code{cgit-service-type}. As its name indicates, an
30652 opaque configuration does not have easy reflective capabilities.
30654 Available @code{opaque-cgit-configuration} fields are:
30656 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
30660 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
30661 The contents of the @code{cgitrc}, as a string.
30664 For example, if your @code{cgitrc} is just the empty string, you
30665 could instantiate a cgit service like this:
30668 (service cgit-service-type
30669 (opaque-cgit-configuration
30673 @subsubheading Gitolite Service
30675 @cindex Gitolite service
30676 @cindex Git, hosting
30677 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
30678 repositories on a central server.
30680 Gitolite can handle multiple repositories and users, and supports flexible
30681 configuration of the permissions for the users on the repositories.
30683 The following example will configure Gitolite using the default @code{git}
30684 user, and the provided SSH public key.
30687 (service gitolite-service-type
30688 (gitolite-configuration
30689 (admin-pubkey (plain-file
30691 "ssh-rsa AAAA... guix@@example.com"))))
30694 Gitolite is configured through a special admin repository which you can clone,
30695 for example, if you setup Gitolite on @code{example.com}, you would run the
30696 following command to clone the admin repository.
30699 git clone git@@example.com:gitolite-admin
30702 When the Gitolite service is activated, the provided @code{admin-pubkey} will
30703 be inserted in to the @file{keydir} directory in the gitolite-admin
30704 repository. If this results in a change in the repository, it will be
30705 committed using the message ``gitolite setup by GNU Guix''.
30707 @deftp {Data Type} gitolite-configuration
30708 Data type representing the configuration for @code{gitolite-service-type}.
30711 @item @code{package} (default: @var{gitolite})
30712 Gitolite package to use.
30714 @item @code{user} (default: @var{git})
30715 User to use for Gitolite. This will be user that you use when accessing
30718 @item @code{group} (default: @var{git})
30719 Group to use for Gitolite.
30721 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
30722 Directory in which to store the Gitolite configuration and repositories.
30724 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
30725 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
30726 representing the configuration for Gitolite.
30728 @item @code{admin-pubkey} (default: @var{#f})
30729 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
30730 setup Gitolite. This will be inserted in to the @file{keydir} directory
30731 within the gitolite-admin repository.
30733 To specify the SSH key as a string, use the @code{plain-file} function.
30736 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
30742 @deftp {Data Type} gitolite-rc-file
30743 Data type representing the Gitolite RC file.
30746 @item @code{umask} (default: @code{#o0077})
30747 This controls the permissions Gitolite sets on the repositories and their
30750 A value like @code{#o0027} will give read access to the group used by Gitolite
30751 (by default: @code{git}). This is necessary when using Gitolite with software
30752 like cgit or gitweb.
30754 @item @code{git-config-keys} (default: @code{""})
30755 Gitolite allows you to set git config values using the @samp{config}
30756 keyword. This setting allows control over the config keys to accept.
30758 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
30759 Set the role names allowed to be used by users running the perms command.
30761 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
30762 This setting controls the commands and features to enable within Gitolite.
30768 @node Game Services
30769 @subsection Game Services
30771 @subsubheading The Battle for Wesnoth Service
30773 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
30774 based tactical strategy game, with several single player campaigns, and
30775 multiplayer games (both networked and local).
30777 @defvar {Scheme Variable} wesnothd-service-type
30778 Service type for the wesnothd service. Its value must be a
30779 @code{wesnothd-configuration} object. To run wesnothd in the default
30780 configuration, instantiate it as:
30783 (service wesnothd-service-type)
30787 @deftp {Data Type} wesnothd-configuration
30788 Data type representing the configuration of @command{wesnothd}.
30791 @item @code{package} (default: @code{wesnoth-server})
30792 The wesnoth server package to use.
30794 @item @code{port} (default: @code{15000})
30795 The port to bind the server to.
30800 @node PAM Mount Service
30801 @subsection PAM Mount Service
30804 The @code{(gnu services pam-mount)} module provides a service allowing
30805 users to mount volumes when they log in. It should be able to mount any
30806 volume format supported by the system.
30808 @defvar {Scheme Variable} pam-mount-service-type
30809 Service type for PAM Mount support.
30812 @deftp {Data Type} pam-mount-configuration
30813 Data type representing the configuration of PAM Mount.
30815 It takes the following parameters:
30819 The configuration rules that will be used to generate
30820 @file{/etc/security/pam_mount.conf.xml}.
30822 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
30823 Guile Reference Manual}), and the default ones don't mount anything for
30827 `((debug (@@ (enable "0")))
30828 (mntoptions (@@ (allow ,(string-join
30829 '("nosuid" "nodev" "loop"
30830 "encryption" "fsck" "nonempty"
30831 "allow_root" "allow_other")
30833 (mntoptions (@@ (require "nosuid,nodev")))
30834 (logout (@@ (wait "0")
30838 (mkmountpoint (@@ (enable "1")
30842 Some @code{volume} elements must be added to automatically mount volumes
30843 at login. Here's an example allowing the user @code{alice} to mount her
30844 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
30845 the partition where he stores his data:
30848 (define pam-mount-rules
30849 `((debug (@@ (enable "0")))
30850 (volume (@@ (user "alice")
30853 (mountpoint "/home/alice")))
30854 (volume (@@ (user "bob")
30857 (mountpoint "/home/bob/data")
30858 (options "defaults,autodefrag,compress")))
30859 (mntoptions (@@ (allow ,(string-join
30860 '("nosuid" "nodev" "loop"
30861 "encryption" "fsck" "nonempty"
30862 "allow_root" "allow_other")
30864 (mntoptions (@@ (require "nosuid,nodev")))
30865 (logout (@@ (wait "0")
30869 (mkmountpoint (@@ (enable "1")
30870 (remove "true")))))
30872 (service pam-mount-service-type
30873 (pam-mount-configuration
30874 (rules pam-mount-rules)))
30877 The complete list of possible options can be found in the man page for
30878 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
30883 @node Guix Services
30884 @subsection Guix Services
30886 @subsubheading Guix Build Coordinator
30887 The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
30888 Coordinator} aids in distributing derivation builds among machines
30889 running an @dfn{agent}. The build daemon is still used to build the
30890 derivations, but the Guix Build Coordinator manages allocating builds
30891 and working with the results.
30894 This service is considered experimental. Configuration options may be
30895 changed in a backwards-incompatible manner, and not all features have
30896 been thorougly tested.
30899 The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
30900 more connected @dfn{agent} processes. The coordinator process handles
30901 clients submitting builds, and allocating builds to agents. The agent
30902 processes talk to a build daemon to actually perform the builds, then
30903 send the results back to the coordinator.
30905 There is a script to run the coordinator component of the Guix Build
30906 Coordinator, but the Guix service uses a custom Guile script instead, to
30907 provide better integration with G-expressions used in the configuration.
30909 @defvar {Scheme Variable} guix-build-coordinator-service-type
30910 Service type for the Guix Build Coordinator. Its value must be a
30911 @code{guix-build-coordinator-configuration} object.
30914 @deftp {Data Type} guix-build-coordinator-configuration
30915 Data type representing the configuration of the Guix Build Coordinator.
30918 @item @code{package} (default: @code{guix-build-coordinator})
30919 The Guix Build Coordinator package to use.
30921 @item @code{user} (default: @code{"guix-build-coordinator"})
30922 The system user to run the service as.
30924 @item @code{group} (default: @code{"guix-build-coordinator"})
30925 The system group to run the service as.
30927 @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
30928 The URI to use for the database.
30930 @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
30931 The URI describing how to listen to requests from agent processes.
30933 @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
30934 The URI describing how to listen to requests from clients. The client
30935 API allows submitting builds and currently isn't authenticated, so take
30936 care when configuring this value.
30938 @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
30939 A G-expression for the allocation strategy to be used. This is a
30940 procedure that takes the datastore as an argument and populates the
30941 allocation plan in the database.
30943 @item @code{hooks} (default: @var{'()})
30944 An association list of hooks. These provide a way to execute arbitrary
30945 code upon certain events, like a build result being processed.
30947 @item @code{guile} (default: @code{guile-3.0-latest})
30948 The Guile package with which to run the Guix Build Coordinator.
30953 @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
30954 Service type for a Guix Build Coordinator agent. Its value must be a
30955 @code{guix-build-coordinator-agent-configuration} object.
30958 @deftp {Data Type} guix-build-coordinator-agent-configuration
30959 Data type representing the configuration a Guix Build Coordinator agent.
30962 @item @code{package} (default: @code{guix-build-coordinator})
30963 The Guix Build Coordinator package to use.
30965 @item @code{user} (default: @code{"guix-build-coordinator-agent"})
30966 The system user to run the service as.
30968 @item @code{coordinator} (default: @code{"http://localhost:8745"})
30969 The URI to use when connecting to the coordinator.
30971 @item @code{authentication}
30972 Record describing how this agent should authenticate with the
30973 coordinator. Possible record types are described below.
30975 @item @code{systems} (default: @code{#f})
30976 The systems for which this agent should fetch builds. The agent process
30977 will use the current system it's running on as the default.
30979 @item @code{max-parallel-builds} (default: @code{1})
30980 The number of builds to perform in parallel.
30982 @item @code{derivation-substitute-urls} (default: @code{#f})
30983 URLs from which to attempt to fetch substitutes for derivations, if the
30984 derivations aren't already available.
30986 @item @code{non-derivation-substitute-urls} (default: @code{#f})
30987 URLs from which to attempt to fetch substitutes for build inputs, if the
30988 input store items aren't already available.
30993 @deftp {Data Type} guix-build-coordinator-agent-password-auth
30994 Data type representing an agent authenticating with a coordinator via a
30999 The UUID of the agent. This should be generated by the coordinator
31000 process, stored in the coordinator database, and used by the intended
31003 @item @code{password}
31004 The password to use when connecting to the coordinator.
31009 @deftp {Data Type} guix-build-coordinator-agent-password-file-auth
31010 Data type representing an agent authenticating with a coordinator via a
31011 UUID and password read from a file.
31015 The UUID of the agent. This should be generated by the coordinator
31016 process, stored in the coordinator database, and used by the intended
31019 @item @code{password-file}
31020 A file containing the password to use when connecting to the
31026 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth
31027 Data type representing an agent authenticating with a coordinator via a
31028 dyanmic auth token and agent name.
31031 @item @code{agent-name}
31032 Name of an agent, this is used to match up to an existing entry in the
31033 database if there is one. When no existing entry is found, a new entry
31034 is automatically added.
31037 Dynamic auth token, this is created and stored in the coordinator
31038 database, and is used by the agent to authenticate.
31043 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth-with-file
31044 Data type representing an agent authenticating with a coordinator via a
31045 dyanmic auth token read from a file and agent name.
31048 @item @code{agent-name}
31049 Name of an agent, this is used to match up to an existing entry in the
31050 database if there is one. When no existing entry is found, a new entry
31051 is automatically added.
31053 @item @code{token-file}
31054 File containing the dynamic auth token, this is created and stored in
31055 the coordinator database, and is used by the agent to authenticate.
31060 The Guix Build Coordinator package contains a script to query an
31061 instance of the Guix Data Service for derivations to build, and then
31062 submit builds for those derivations to the coordinator. The service
31063 type below assists in running this script. This is an additional tool
31064 that may be useful when building derivations contained within an
31065 instance of the Guix Data Service.
31067 @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
31068 Service type for the
31069 guix-build-coordinator-queue-builds-from-guix-data-service script. Its
31070 value must be a @code{guix-build-coordinator-queue-builds-configuration}
31074 @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
31075 Data type representing the options to the queue builds from guix data
31079 @item @code{package} (default: @code{guix-build-coordinator})
31080 The Guix Build Coordinator package to use.
31082 @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
31083 The system user to run the service as.
31085 @item @code{coordinator} (default: @code{"http://localhost:8745"})
31086 The URI to use when connecting to the coordinator.
31088 @item @code{systems} (default: @code{#f})
31089 The systems for which to fetch derivations to build.
31091 @item @code{systems-and-targets} (default: @code{#f})
31092 An association list of system and target pairs for which to fetch
31093 derivations to build.
31095 @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
31096 The Guix Data Service instance from which to query to find out about
31097 derivations to build.
31099 @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
31100 A file to record which commits have been processed, to avoid needlessly
31101 processing them again if the service is restarted.
31106 @subsubheading Guix Data Service
31107 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
31108 and provides data about GNU Guix. This includes information about
31109 packages, derivations and lint warnings.
31111 The data is stored in a PostgreSQL database, and available through a web
31114 @defvar {Scheme Variable} guix-data-service-type
31115 Service type for the Guix Data Service. Its value must be a
31116 @code{guix-data-service-configuration} object. The service optionally
31117 extends the getmail service, as the guix-commits mailing list is used to
31118 find out about changes in the Guix git repository.
31121 @deftp {Data Type} guix-data-service-configuration
31122 Data type representing the configuration of the Guix Data Service.
31125 @item @code{package} (default: @code{guix-data-service})
31126 The Guix Data Service package to use.
31128 @item @code{user} (default: @code{"guix-data-service"})
31129 The system user to run the service as.
31131 @item @code{group} (default: @code{"guix-data-service"})
31132 The system group to run the service as.
31134 @item @code{port} (default: @code{8765})
31135 The port to bind the web service to.
31137 @item @code{host} (default: @code{"127.0.0.1"})
31138 The host to bind the web service to.
31140 @item @code{getmail-idle-mailboxes} (default: @code{#f})
31141 If set, this is the list of mailboxes that the getmail service will be
31142 configured to listen to.
31144 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
31145 If set, this is the @code{getmail-retriever-configuration} object with
31146 which to configure getmail to fetch mail from the guix-commits mailing
31149 @item @code{extra-options} (default: @var{'()})
31150 Extra command line options for @code{guix-data-service}.
31152 @item @code{extra-process-jobs-options} (default: @var{'()})
31153 Extra command line options for @code{guix-data-service-process-jobs}.
31158 @node Linux Services
31159 @subsection Linux Services
31162 @cindex out of memory killer
31164 @cindex early out of memory daemon
31165 @subsubheading Early OOM Service
31167 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
31168 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
31169 space and provides a more responsive and configurable alternative to the
31170 in-kernel OOM killer. It is useful to prevent the system from becoming
31171 unresponsive when it runs out of memory.
31173 @deffn {Scheme Variable} earlyoom-service-type
31174 The service type for running @command{earlyoom}, the Early OOM daemon.
31175 Its value must be a @code{earlyoom-configuration} object, described
31176 below. The service can be instantiated in its default configuration
31180 (service earlyoom-service-type)
31184 @deftp {Data Type} earlyoom-configuration
31185 This is the configuration record for the @code{earlyoom-service-type}.
31188 @item @code{earlyoom} (default: @var{earlyoom})
31189 The Earlyoom package to use.
31191 @item @code{minimum-available-memory} (default: @code{10})
31192 The threshold for the minimum @emph{available} memory, in percentages.
31194 @item @code{minimum-free-swap} (default: @code{10})
31195 The threshold for the minimum free swap memory, in percentages.
31197 @item @code{prefer-regexp} (default: @code{#f})
31198 A regular expression (as a string) to match the names of the processes
31199 that should be preferably killed.
31201 @item @code{avoid-regexp} (default: @code{#f})
31202 A regular expression (as a string) to match the names of the processes
31203 that should @emph{not} be killed.
31205 @item @code{memory-report-interval} (default: @code{0})
31206 The interval in seconds at which a memory report is printed. It is
31207 disabled by default.
31209 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
31210 A boolean indicating whether the positive adjustments set in
31211 @file{/proc/*/oom_score_adj} should be ignored.
31213 @item @code{show-debug-messages?} (default: @code{#f})
31214 A boolean indicating whether debug messages should be printed. The logs
31215 are saved at @file{/var/log/earlyoom.log}.
31217 @item @code{send-notification-command} (default: @code{#f})
31218 This can be used to provide a custom command used for sending
31224 @cindex kernel module loader
31225 @subsubheading Kernel Module Loader Service
31227 The kernel module loader service allows one to load loadable kernel
31228 modules at boot. This is especially useful for modules that don't
31229 autoload and need to be manually loaded, as it's the case with
31232 @deffn {Scheme Variable} kernel-module-loader-service-type
31233 The service type for loading loadable kernel modules at boot with
31234 @command{modprobe}. Its value must be a list of strings representing
31235 module names. For example loading the drivers provided by
31236 @code{ddcci-driver-linux}, in debugging mode by passing some module
31237 parameters, can be done as follow:
31240 (use-modules (gnu) (gnu services))
31241 (use-package-modules linux)
31242 (use-service-modules linux)
31244 (define ddcci-config
31245 (plain-file "ddcci.conf"
31246 "options ddcci dyndbg delay=120"))
31250 (services (cons* (service kernel-module-loader-service-type
31251 '("ddcci" "ddcci_backlight"))
31252 (simple-service 'ddcci-config etc-service-type
31253 (list `("modprobe.d/ddcci.conf"
31256 (kernel-loadable-modules (list ddcci-driver-linux)))
31261 @cindex compressed swap
31262 @cindex Compressed RAM-based block devices
31263 @subsubheading Zram Device Service
31265 The Zram device service provides a compressed swap device in system
31266 memory. The Linux Kernel documentation has more information about
31267 @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
31270 @deffn {Scheme Variable} zram-device-service-type
31271 This service creates the zram block device, formats it as swap and
31272 enables it as a swap device. The service's value is a
31273 @code{zram-device-configuration} record.
31275 @deftp {Data Type} zram-device-configuration
31276 This is the data type representing the configuration for the zram-device
31280 @item @code{size} (default @code{"1G"})
31281 This is the amount of space you wish to provide for the zram device. It
31282 accepts a string and can be a number of bytes or use a suffix, eg.:
31283 @code{"512M"} or @code{1024000}.
31284 @item @code{compression-algorithm} (default @code{'lzo})
31285 This is the compression algorithm you wish to use. It is difficult to
31286 list all the possible compression options, but common ones supported by
31287 Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
31288 @item @code{memory-limit} (default @code{0})
31289 This is the maximum amount of memory which the zram device can use.
31290 Setting it to '0' disables the limit. While it is generally expected
31291 that compression will be 2:1, it is possible that uncompressable data
31292 can be written to swap and this is a method to limit how much memory can
31293 be used. It accepts a string and can be a number of bytes or use a
31294 suffix, eg.: @code{"2G"}.
31295 @item @code{priority} (default @code{-1})
31296 This is the priority of the swap device created from the zram device.
31297 @code{swapon} accepts values between -1 and 32767, with higher values
31298 indicating higher priority. Higher priority swap will generally be used
31305 @node Hurd Services
31306 @subsection Hurd Services
31308 @defvr {Scheme Variable} hurd-console-service-type
31309 This service starts the fancy @code{VGA} console client on the Hurd.
31311 The service's value is a @code{hurd-console-configuration} record.
31314 @deftp {Data Type} hurd-console-configuration
31315 This is the data type representing the configuration for the
31316 hurd-console-service.
31319 @item @code{hurd} (default: @var{hurd})
31320 The Hurd package to use.
31324 @defvr {Scheme Variable} hurd-getty-service-type
31325 This service starts a tty using the Hurd @code{getty} program.
31327 The service's value is a @code{hurd-getty-configuration} record.
31330 @deftp {Data Type} hurd-getty-configuration
31331 This is the data type representing the configuration for the
31332 hurd-getty-service.
31335 @item @code{hurd} (default: @var{hurd})
31336 The Hurd package to use.
31339 The name of the console this Getty runs on---e.g., @code{"tty1"}.
31341 @item @code{baud-rate} (default: @code{38400})
31342 An integer specifying the baud rate of the tty.
31347 @node Miscellaneous Services
31348 @subsection Miscellaneous Services
31350 @cindex fingerprint
31351 @subsubheading Fingerprint Service
31353 The @code{(gnu services authentication)} module provides a DBus service to
31354 read and identify fingerprints via a fingerprint sensor.
31356 @defvr {Scheme Variable} fprintd-service-type
31357 The service type for @command{fprintd}, which provides the fingerprint
31358 reading capability.
31361 (service fprintd-service-type)
31366 @subsubheading System Control Service
31368 The @code{(gnu services sysctl)} provides a service to configure kernel
31369 parameters at boot.
31371 @defvr {Scheme Variable} sysctl-service-type
31372 The service type for @command{sysctl}, which modifies kernel parameters
31373 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
31377 (service sysctl-service-type
31378 (sysctl-configuration
31379 (settings '(("net.ipv4.ip_forward" . "1")))))
31383 @deftp {Data Type} sysctl-configuration
31384 The data type representing the configuration of @command{sysctl}.
31387 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
31388 The @command{sysctl} executable to use.
31390 @item @code{settings} (default: @code{'()})
31391 An association list specifies kernel parameters and their values.
31396 @subsubheading PC/SC Smart Card Daemon Service
31398 The @code{(gnu services security-token)} module provides the following service
31399 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
31400 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
31401 manager that coordinates communications with smart card readers, smart cards
31402 and cryptographic tokens that are connected to the system.
31404 @defvr {Scheme Variable} pcscd-service-type
31405 Service type for the @command{pcscd} service. Its value must be a
31406 @code{pcscd-configuration} object. To run pcscd in the default
31407 configuration, instantiate it as:
31410 (service pcscd-service-type)
31414 @deftp {Data Type} pcscd-configuration
31415 The data type representing the configuration of @command{pcscd}.
31418 @item @code{pcsc-lite} (default: @code{pcsc-lite})
31419 The pcsc-lite package that provides pcscd.
31420 @item @code{usb-drivers} (default: @code{(list ccid)})
31421 List of packages that provide USB drivers to pcscd. Drivers are expected to be
31422 under @file{pcsc/drivers} in the store directory of the package.
31427 @subsubheading Lirc Service
31429 The @code{(gnu services lirc)} module provides the following service.
31431 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
31432 [#:device #f] [#:driver #f] [#:config-file #f] @
31433 [#:extra-options '()]
31434 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
31435 decodes infrared signals from remote controls.
31437 Optionally, @var{device}, @var{driver} and @var{config-file}
31438 (configuration file name) may be specified. See @command{lircd} manual
31441 Finally, @var{extra-options} is a list of additional command-line options
31442 passed to @command{lircd}.
31446 @subsubheading Spice Service
31448 The @code{(gnu services spice)} module provides the following service.
31450 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
31451 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
31452 that enables sharing the clipboard with a vm and setting the guest display
31453 resolution when the graphical console window resizes.
31456 @cindex inputattach
31457 @subsubheading inputattach Service
31459 @cindex tablet input, for Xorg
31460 @cindex touchscreen input, for Xorg
31461 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
31462 use input devices such as Wacom tablets, touchscreens, or joysticks with the
31463 Xorg display server.
31465 @deffn {Scheme Variable} inputattach-service-type
31466 Type of a service that runs @command{inputattach} on a device and
31467 dispatches events from it.
31470 @deftp {Data Type} inputattach-configuration
31472 @item @code{device-type} (default: @code{"wacom"})
31473 The type of device to connect to. Run @command{inputattach --help}, from the
31474 @code{inputattach} package, to see the list of supported device types.
31476 @item @code{device} (default: @code{"/dev/ttyS0"})
31477 The device file to connect to the device.
31479 @item @code{baud-rate} (default: @code{#f})
31480 Baud rate to use for the serial connection.
31481 Should be a number or @code{#f}.
31483 @item @code{log-file} (default: @code{#f})
31484 If true, this must be the name of a file to log messages to.
31488 @subsubheading Dictionary Service
31490 The @code{(gnu services dict)} module provides the following service:
31492 @defvr {Scheme Variable} dicod-service-type
31493 This is the type of the service that runs the @command{dicod} daemon, an
31494 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
31497 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
31498 Return a service that runs the @command{dicod} daemon, an implementation
31499 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
31501 The optional @var{config} argument specifies the configuration for
31502 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
31503 default it serves the GNU Collaborative International Dictionary of English.
31505 You can add @command{open localhost} to your @file{~/.dico} file to make
31506 @code{localhost} the default server for @command{dico} client
31507 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
31510 @deftp {Data Type} dicod-configuration
31511 Data type representing the configuration of dicod.
31514 @item @code{dico} (default: @var{dico})
31515 Package object of the GNU Dico dictionary server.
31517 @item @code{interfaces} (default: @var{'("localhost")})
31518 This is the list of IP addresses and ports and possibly socket file
31519 names to listen to (@pxref{Server Settings, @code{listen} directive,,
31520 dico, GNU Dico Manual}).
31522 @item @code{handlers} (default: @var{'()})
31523 List of @code{<dicod-handler>} objects denoting handlers (module instances).
31525 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
31526 List of @code{<dicod-database>} objects denoting dictionaries to be served.
31530 @deftp {Data Type} dicod-handler
31531 Data type representing a dictionary handler (module instance).
31535 Name of the handler (module instance).
31537 @item @code{module} (default: @var{#f})
31538 Name of the dicod module of the handler (instance). If it is @code{#f},
31539 the module has the same name as the handler.
31540 (@pxref{Modules,,, dico, GNU Dico Manual}).
31542 @item @code{options}
31543 List of strings or gexps representing the arguments for the module handler
31547 @deftp {Data Type} dicod-database
31548 Data type representing a dictionary database.
31552 Name of the database, will be used in DICT commands.
31554 @item @code{handler}
31555 Name of the dicod handler (module instance) used by this database
31556 (@pxref{Handlers,,, dico, GNU Dico Manual}).
31558 @item @code{complex?} (default: @var{#f})
31559 Whether the database configuration complex. The complex configuration
31560 will need a corresponding @code{<dicod-handler>} object, otherwise not.
31562 @item @code{options}
31563 List of strings or gexps representing the arguments for the database
31564 (@pxref{Databases,,, dico, GNU Dico Manual}).
31568 @defvr {Scheme Variable} %dicod-database:gcide
31569 A @code{<dicod-database>} object serving the GNU Collaborative International
31570 Dictionary of English using the @code{gcide} package.
31573 The following is an example @code{dicod-service} configuration.
31576 (dicod-service #:config
31577 (dicod-configuration
31578 (handlers (list (dicod-handler
31582 (list #~(string-append "dbdir=" #$wordnet))))))
31583 (databases (list (dicod-database
31586 (handler "wordnet")
31587 (options '("database=wn")))
31588 %dicod-database:gcide))))
31592 @subsubheading Docker Service
31594 The @code{(gnu services docker)} module provides the following services.
31596 @defvr {Scheme Variable} docker-service-type
31598 This is the type of the service that runs @url{https://www.docker.com,Docker},
31599 a daemon that can execute application bundles (sometimes referred to as
31600 ``containers'') in isolated environments.
31604 @deftp {Data Type} docker-configuration
31605 This is the data type representing the configuration of Docker and Containerd.
31609 @item @code{package} (default: @code{docker})
31610 The Docker daemon package to use.
31612 @item @code{package} (default: @code{docker-cli})
31613 The Docker client package to use.
31615 @item @code{containerd} (default: @var{containerd})
31616 The Containerd package to use.
31618 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
31619 The Docker user-land networking proxy package to use.
31621 @item @code{enable-proxy?} (default @code{#t})
31622 Enable or disable the use of the Docker user-land networking proxy.
31624 @item @code{debug?} (default @code{#f})
31625 Enable or disable debug output.
31627 @item @code{enable-iptables?} (default @code{#t})
31628 Enable or disable the addition of iptables rules.
31633 @cindex Singularity, container service
31634 @defvr {Scheme Variable} singularity-service-type
31635 This is the type of the service that allows you to run
31636 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
31637 create and run application bundles (aka. ``containers''). The value for this
31638 service is the Singularity package to use.
31640 The service does not install a daemon; instead, it installs helper programs as
31641 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
31642 @command{singularity run} and similar commands.
31646 @subsubheading Auditd Service
31648 The @code{(gnu services auditd)} module provides the following service.
31650 @defvr {Scheme Variable} auditd-service-type
31652 This is the type of the service that runs
31653 @url{https://people.redhat.com/sgrubb/audit/,auditd},
31654 a daemon that tracks security-relevant information on your system.
31656 Examples of things that can be tracked:
31666 Failed login attempts
31673 @command{auditctl} from the @code{audit} package can be used in order
31674 to add or remove events to be tracked (until the next reboot).
31675 In order to permanently track events, put the command line arguments
31676 of auditctl into a file called @code{audit.rules} in the configuration
31677 directory (see below).
31678 @command{aureport} from the @code{audit} package can be used in order
31679 to view a report of all recorded events.
31680 The audit daemon by default logs into the file
31681 @file{/var/log/audit.log}.
31685 @deftp {Data Type} auditd-configuration
31686 This is the data type representing the configuration of auditd.
31690 @item @code{audit} (default: @code{audit})
31691 The audit package to use.
31693 @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
31694 The directory containing the configuration file for the audit package, which
31695 must be named @code{auditd.conf}, and optionally some audit rules to
31696 instantiate on startup.
31702 @subsubheading R-Shiny service
31704 The @code{(gnu services science)} module provides the following service.
31706 @defvr {Scheme Variable} rshiny-service-type
31708 This is a type of service which is used to run a webapp created with
31709 @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
31710 variable and runs the provided script to call @code{runApp}.
31712 @deftp {Data Type} rshiny-configuration
31713 This is the data type representing the configuration of rshiny.
31717 @item @code{package} (default: @code{r-shiny})
31718 The package to use.
31720 @item @code{binary} (defaunlt @code{"rshiny"})
31721 The name of the binary or shell script located at @code{package/bin/} to
31722 run when the service is run.
31724 The common way to create this file is as follows:
31728 (let* ((out (assoc-ref %outputs "out"))
31729 (targetdir (string-append out "/share/" ,name))
31730 (app (string-append out "/bin/" ,name))
31731 (Rbin (string-append (assoc-ref %build-inputs "r-min")
31734 (mkdir-p (string-append out "/bin"))
31735 (call-with-output-file app
31741 runApp(launch.browser=0, port=4202)~%\n"
31750 @subsubheading Nix service
31752 The @code{(gnu services nix)} module provides the following service.
31754 @defvr {Scheme Variable} nix-service-type
31756 This is the type of the service that runs build daemon of the
31757 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
31761 (use-modules (gnu))
31762 (use-service-modules nix)
31763 (use-package-modules package-management)
31767 (packages (append (list nix)
31770 (services (append (list (service nix-service-type))
31774 After @command{guix system reconfigure} configure Nix for your user:
31777 @item Add a Nix channel and update it. See
31778 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
31780 @item Create a symlink to your profile and activate Nix profile:
31784 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
31785 $ source /run/current-system/profile/etc/profile.d/nix.sh
31790 @deftp {Data Type} nix-configuration
31791 This data type represents the configuration of the Nix daemon.
31794 @item @code{nix} (default: @code{nix})
31795 The Nix package to use.
31797 @item @code{sandbox} (default: @code{#t})
31798 Specifies whether builds are sandboxed by default.
31800 @item @code{build-sandbox-items} (default: @code{'()})
31801 This is a list of strings or objects appended to the
31802 @code{build-sandbox-items} field of the configuration file.
31804 @item @code{extra-config} (default: @code{'()})
31805 This is a list of strings or objects appended to the configuration file.
31806 It is used to pass extra text to be added verbatim to the configuration
31809 @item @code{extra-options} (default: @code{'()})
31810 Extra command line options for @code{nix-service-type}.
31814 @node Setuid Programs
31815 @section Setuid Programs
31817 @cindex setuid programs
31818 Some programs need to run with ``root'' privileges, even when they are
31819 launched by unprivileged users. A notorious example is the
31820 @command{passwd} program, which users can run to change their
31821 password, and which needs to access the @file{/etc/passwd} and
31822 @file{/etc/shadow} files---something normally restricted to root, for
31823 obvious security reasons. To address that, these executables are
31824 @dfn{setuid-root}, meaning that they always run with root privileges
31825 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
31826 for more info about the setuid mechanism).
31828 The store itself @emph{cannot} contain setuid programs: that would be a
31829 security issue since any user on the system can write derivations that
31830 populate the store (@pxref{The Store}). Thus, a different mechanism is
31831 used: instead of changing the setuid bit directly on files that are in
31832 the store, we let the system administrator @emph{declare} which programs
31833 should be setuid root.
31835 The @code{setuid-programs} field of an @code{operating-system}
31836 declaration contains a list of G-expressions denoting the names of
31837 programs to be setuid-root (@pxref{Using the Configuration System}).
31838 For instance, the @command{passwd} program, which is part of the Shadow
31839 package, can be designated by this G-expression (@pxref{G-Expressions}):
31842 #~(string-append #$shadow "/bin/passwd")
31845 A default set of setuid programs is defined by the
31846 @code{%setuid-programs} variable of the @code{(gnu system)} module.
31848 @defvr {Scheme Variable} %setuid-programs
31849 A list of G-expressions denoting common programs that are setuid-root.
31851 The list includes commands such as @command{passwd}, @command{ping},
31852 @command{su}, and @command{sudo}.
31855 Under the hood, the actual setuid programs are created in the
31856 @file{/run/setuid-programs} directory at system activation time. The
31857 files in this directory refer to the ``real'' binaries, which are in the
31860 @node X.509 Certificates
31861 @section X.509 Certificates
31863 @cindex HTTPS, certificates
31864 @cindex X.509 certificates
31866 Web servers available over HTTPS (that is, HTTP over the transport-layer
31867 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
31868 that the client can then use to @emph{authenticate} the server. To do
31869 that, clients verify that the server's certificate is signed by a
31870 so-called @dfn{certificate authority} (CA). But to verify the CA's
31871 signature, clients must have first acquired the CA's certificate.
31873 Web browsers such as GNU@tie{}IceCat include their own set of CA
31874 certificates, such that they are able to verify CA signatures
31877 However, most other programs that can talk HTTPS---@command{wget},
31878 @command{git}, @command{w3m}, etc.---need to be told where CA
31879 certificates can be found.
31881 @cindex @code{nss-certs}
31882 In Guix, this is done by adding a package that provides certificates
31883 to the @code{packages} field of the @code{operating-system} declaration
31884 (@pxref{operating-system Reference}). Guix includes one such package,
31885 @code{nss-certs}, which is a set of CA certificates provided as part of
31886 Mozilla's Network Security Services.
31888 Note that it is @emph{not} part of @code{%base-packages}, so you need to
31889 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
31890 most applications and libraries look for certificates by default, points
31891 to the certificates installed globally.
31893 Unprivileged users, including users of Guix on a foreign distro,
31894 can also install their own certificate package in
31895 their profile. A number of environment variables need to be defined so
31896 that applications and libraries know where to find them. Namely, the
31897 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
31898 variables. Some applications add their own environment variables; for
31899 instance, the Git version control system honors the certificate bundle
31900 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
31901 would typically run something like:
31904 guix install nss-certs
31905 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
31906 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
31907 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
31910 As another example, R requires the @env{CURL_CA_BUNDLE} environment
31911 variable to point to a certificate bundle, so you would have to run
31912 something like this:
31915 guix install nss-certs
31916 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
31919 For other applications you may want to look up the required environment
31920 variable in the relevant documentation.
31923 @node Name Service Switch
31924 @section Name Service Switch
31926 @cindex name service switch
31928 The @code{(gnu system nss)} module provides bindings to the
31929 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
31930 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
31931 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
31932 extended with new ``name'' lookup methods for system databases, which
31933 includes host names, service names, user accounts, and more (@pxref{Name
31934 Service Switch, System Databases and Name Service Switch,, libc, The GNU
31935 C Library Reference Manual}).
31937 The NSS configuration specifies, for each system database, which lookup
31938 method is to be used, and how the various methods are chained
31939 together---for instance, under which circumstances NSS should try the
31940 next method in the list. The NSS configuration is given in the
31941 @code{name-service-switch} field of @code{operating-system} declarations
31942 (@pxref{operating-system Reference, @code{name-service-switch}}).
31945 @cindex .local, host name lookup
31946 As an example, the declaration below configures the NSS to use the
31947 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
31948 back-end}, which supports host name lookups over multicast DNS (mDNS)
31949 for host names ending in @code{.local}:
31952 (name-service-switch
31953 (hosts (list %files ;first, check /etc/hosts
31955 ;; If the above did not succeed, try
31956 ;; with 'mdns_minimal'.
31958 (name "mdns_minimal")
31960 ;; 'mdns_minimal' is authoritative for
31961 ;; '.local'. When it returns "not found",
31962 ;; no need to try the next methods.
31963 (reaction (lookup-specification
31964 (not-found => return))))
31966 ;; Then fall back to DNS.
31970 ;; Finally, try with the "full" 'mdns'.
31975 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
31976 contains this configuration, so you will not have to type it if all you
31977 want is to have @code{.local} host lookup working.
31979 Note that, in this case, in addition to setting the
31980 @code{name-service-switch} of the @code{operating-system} declaration,
31981 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
31982 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
31983 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
31984 to the name service cache daemon (@pxref{Base Services,
31985 @code{nscd-service}}).
31987 For convenience, the following variables provide typical NSS
31990 @defvr {Scheme Variable} %default-nss
31991 This is the default name service switch configuration, a
31992 @code{name-service-switch} object.
31995 @defvr {Scheme Variable} %mdns-host-lookup-nss
31996 This is the name service switch configuration with support for host name
31997 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
32000 The reference for name service switch configuration is given below. It
32001 is a direct mapping of the configuration file format of the C library , so
32002 please refer to the C library manual for more information (@pxref{NSS
32003 Configuration File,,, libc, The GNU C Library Reference Manual}).
32004 Compared to the configuration file format of libc NSS, it has the advantage
32005 not only of adding this warm parenthetic feel that we like, but also
32006 static checks: you will know about syntax errors and typos as soon as you
32007 run @command{guix system}.
32009 @deftp {Data Type} name-service-switch
32011 This is the data type representation the configuration of libc's name
32012 service switch (NSS). Each field below represents one of the supported
32029 The system databases handled by the NSS@. Each of these fields must be a
32030 list of @code{<name-service>} objects (see below).
32034 @deftp {Data Type} name-service
32036 This is the data type representing an actual name service and the
32037 associated lookup action.
32041 A string denoting the name service (@pxref{Services in the NSS
32042 configuration,,, libc, The GNU C Library Reference Manual}).
32044 Note that name services listed here must be visible to nscd. This is
32045 achieved by passing the @code{#:name-services} argument to
32046 @code{nscd-service} the list of packages providing the needed name
32047 services (@pxref{Base Services, @code{nscd-service}}).
32050 An action specified using the @code{lookup-specification} macro
32051 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
32052 Reference Manual}). For example:
32055 (lookup-specification (unavailable => continue)
32056 (success => return))
32061 @node Initial RAM Disk
32062 @section Initial RAM Disk
32065 @cindex initial RAM disk
32066 For bootstrapping purposes, the Linux-Libre kernel is passed an
32067 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
32068 root file system as well as an initialization script. The latter is
32069 responsible for mounting the real root file system, and for loading any
32070 kernel modules that may be needed to achieve that.
32072 The @code{initrd-modules} field of an @code{operating-system}
32073 declaration allows you to specify Linux-libre kernel modules that must
32074 be available in the initrd. In particular, this is where you would list
32075 modules needed to actually drive the hard disk where your root partition
32076 is---although the default value of @code{initrd-modules} should cover
32077 most use cases. For example, assuming you need the @code{megaraid_sas}
32078 module in addition to the default modules to be able to access your root
32079 file system, you would write:
32084 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
32087 @defvr {Scheme Variable} %base-initrd-modules
32088 This is the list of kernel modules included in the initrd by default.
32091 Furthermore, if you need lower-level customization, the @code{initrd}
32092 field of an @code{operating-system} declaration allows
32093 you to specify which initrd you would like to use. The @code{(gnu
32094 system linux-initrd)} module provides three ways to build an initrd: the
32095 high-level @code{base-initrd} procedure and the low-level
32096 @code{raw-initrd} and @code{expression->initrd} procedures.
32098 The @code{base-initrd} procedure is intended to cover most common uses.
32099 For example, if you want to add a bunch of kernel modules to be loaded
32100 at boot time, you can define the @code{initrd} field of the operating
32101 system declaration like this:
32104 (initrd (lambda (file-systems . rest)
32105 ;; Create a standard initrd but set up networking
32106 ;; with the parameters QEMU expects by default.
32107 (apply base-initrd file-systems
32108 #:qemu-networking? #t
32112 The @code{base-initrd} procedure also handles common use cases that
32113 involves using the system as a QEMU guest, or as a ``live'' system with
32114 volatile root file system.
32116 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
32117 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
32118 such as trying to guess which kernel modules and packages should be included
32119 to the initrd. An example use of @code{raw-initrd} is when a user has
32120 a custom Linux kernel configuration and default kernel modules included by
32121 @code{base-initrd} are not available.
32123 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
32124 honors several options passed on the Linux kernel command line
32125 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
32126 @code{-append} option of QEMU), notably:
32129 @item --load=@var{boot}
32130 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
32131 program, once it has mounted the root file system.
32133 Guix uses this option to yield control to a boot program that runs the
32134 service activation programs and then spawns the GNU@tie{}Shepherd, the
32135 initialization system.
32137 @item --root=@var{root}
32138 Mount @var{root} as the root file system. @var{root} can be a device
32139 name like @code{/dev/sda1}, a file system label, or a file system UUID.
32140 When unspecified, the device name from the root file system of the
32141 operating system declaration is used.
32143 @item --system=@var{system}
32144 Have @file{/run/booted-system} and @file{/run/current-system} point to
32147 @item modprobe.blacklist=@var{modules}@dots{}
32148 @cindex module, black-listing
32149 @cindex black list, of kernel modules
32150 Instruct the initial RAM disk as well as the @command{modprobe} command
32151 (from the kmod package) to refuse to load @var{modules}. @var{modules}
32152 must be a comma-separated list of module names---e.g.,
32153 @code{usbkbd,9pnet}.
32156 Start a read-eval-print loop (REPL) from the initial RAM disk before it
32157 tries to load kernel modules and to mount the root file system. Our
32158 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
32159 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
32160 Manual}, for more information on Guile's REPL.
32164 Now that you know all the features that initial RAM disks produced by
32165 @code{base-initrd} and @code{raw-initrd} provide,
32166 here is how to use it and customize it further.
32169 @cindex initial RAM disk
32170 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
32171 [#:linux-modules '()] [#:mapped-devices '()] @
32172 [#:keyboard-layout #f] @
32173 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
32174 Return a derivation that builds a raw initrd. @var{file-systems} is
32175 a list of file systems to be mounted by the initrd, possibly in addition to
32176 the root file system specified on the kernel command line via @option{--root}.
32177 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
32178 @var{mapped-devices} is a list of device mappings to realize before
32179 @var{file-systems} are mounted (@pxref{Mapped Devices}).
32180 @var{helper-packages} is a list of packages to be copied in the initrd.
32182 include @code{e2fsck/static} or other packages needed by the initrd to check
32183 the root file system.
32185 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
32186 the desired console keyboard layout. This is done before @var{mapped-devices}
32187 are set up and before @var{file-systems} are mounted such that, should the
32188 user need to enter a passphrase or use the REPL, this happens using the
32189 intended keyboard layout.
32191 When @var{qemu-networking?} is true, set up networking with the standard QEMU
32192 parameters. When @var{virtio?} is true, load additional modules so that the
32193 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
32195 When @var{volatile-root?} is true, the root file system is writable but any changes
32199 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
32200 [#:mapped-devices '()] [#:keyboard-layout #f] @
32201 [#:qemu-networking? #f] [#:volatile-root? #f] @
32202 [#:linux-modules '()]
32203 Return as a file-like object a generic initrd, with kernel
32204 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
32205 mounted by the initrd, possibly in addition to the root file system specified
32206 on the kernel command line via @option{--root}. @var{mapped-devices} is a list of device
32207 mappings to realize before @var{file-systems} are mounted.
32209 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
32210 the desired console keyboard layout. This is done before @var{mapped-devices}
32211 are set up and before @var{file-systems} are mounted such that, should the
32212 user need to enter a passphrase or use the REPL, this happens using the
32213 intended keyboard layout.
32215 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
32217 The initrd is automatically populated with all the kernel modules necessary
32218 for @var{file-systems} and for the given options. Additional kernel
32219 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
32220 loaded at boot time in the order in which they appear.
32223 Needless to say, the initrds we produce and use embed a
32224 statically-linked Guile, and the initialization program is a Guile
32225 program. That gives a lot of flexibility. The
32226 @code{expression->initrd} procedure builds such an initrd, given the
32227 program to run in that initrd.
32229 @deffn {Scheme Procedure} expression->initrd @var{exp} @
32230 [#:guile %guile-3.0-static-stripped] [#:name "guile-initrd"]
32231 Return as a file-like object a Linux initrd (a gzipped cpio archive)
32232 containing @var{guile} and that evaluates @var{exp}, a G-expression,
32233 upon booting. All the derivations referenced by @var{exp} are
32234 automatically copied to the initrd.
32237 @node Bootloader Configuration
32238 @section Bootloader Configuration
32241 @cindex boot loader
32243 The operating system supports multiple bootloaders. The bootloader is
32244 configured using @code{bootloader-configuration} declaration. All the
32245 fields of this structure are bootloader agnostic except for one field,
32246 @code{bootloader} that indicates the bootloader to be configured and
32249 Some of the bootloaders do not honor every field of
32250 @code{bootloader-configuration}. For instance, the extlinux
32251 bootloader does not support themes and thus ignores the @code{theme}
32254 @deftp {Data Type} bootloader-configuration
32255 The type of a bootloader configuration declaration.
32259 @item @code{bootloader}
32260 @cindex EFI, bootloader
32261 @cindex UEFI, bootloader
32262 @cindex BIOS, bootloader
32263 The bootloader to use, as a @code{bootloader} object. For now
32264 @code{grub-bootloader}, @code{grub-efi-bootloader},
32265 @code{grub-efi-netboot-bootloader}, @code{extlinux-bootloader} and
32266 @code{u-boot-bootloader} are supported.
32268 @cindex ARM, bootloaders
32269 @cindex AArch64, bootloaders
32270 Available bootloaders are described in @code{(gnu bootloader @dots{})}
32271 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
32272 of bootloaders for a wide range of ARM and AArch64 systems, using the
32273 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
32275 @vindex grub-efi-bootloader
32276 @code{grub-efi-bootloader} allows to boot on modern systems using the
32277 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
32278 use if the installation image contains a @file{/sys/firmware/efi} directory
32279 when you boot it on your system.
32281 @vindex grub-bootloader
32282 @code{grub-bootloader} allows you to boot in particular Intel-based machines
32283 in ``legacy'' BIOS mode.
32285 @vindex grub-efi-netboot-bootloader
32286 @code{grub-efi-netboot-bootloader} allows you to boot your system over network
32287 through TFTP@. In combination with an NFS root file system this allows you to
32288 build a diskless Guix system.
32290 The installation of the @code{grub-efi-netboot-bootloader} generates the content
32291 of the TFTP root directory at @code{target}
32292 (@pxref{Bootloader Configuration, @code{target}}), to be served by a TFTP server.
32293 You may want to mount your TFTP server directory onto @code{target} to move the
32294 required files to the TFTP server automatically.
32296 If you plan to use an NFS root file system as well (actually if you mount the
32297 store from an NFS share), then the TFTP server needs to serve the file
32298 @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
32299 image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
32300 initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
32301 files from the store will be accessed by GRUB through TFTP with their normal
32302 store path, for example as
32303 @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
32305 Two symlinks are created to make this possible. The first symlink is
32306 @code{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
32307 @file{../../../boot/grub/grub.cfg},
32308 where @code{target} may be @file{/boot}. In this case the link is not leaving
32309 the served TFTP root directory, but otherwise it does. The second link is
32310 @code{target}@file{/gnu/store} and points to @file{../gnu/store}. This link
32311 is leaving the served TFTP root directory.
32313 The assumption behind all this is that you have an NFS server exporting the root
32314 file system for your Guix system, and additionally a TFTP server exporting your
32315 @code{target} directory—usually @file{/boot}—from that same root file system for
32316 your Guix system. In this constellation the symlinks will work.
32318 For other constellations you will have to program your own bootloader installer,
32319 which then takes care to make necessary files from the store accessible through
32320 TFTP, for example by copying them into the TFTP root directory at @code{target}.
32322 It is important to note that symlinks pointing outside the TFTP root directory
32323 may need to be allowed in the configuration of your TFTP server. Further the
32324 store link exposes the whole store through TFTP@. Both points need to be
32325 considered carefully for security aspects.
32327 Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
32328 NFS servers, you also need a properly configured DHCP server to make the booting
32329 over netboot possible. For all this we can currently only recommend you to look
32330 for instructions about @acronym{PXE, Preboot eXecution Environment}.
32332 @item @code{target}
32333 This is a string denoting the target onto which to install the
32336 The interpretation depends on the bootloader in question. For
32337 @code{grub-bootloader}, for example, it should be a device name understood by
32338 the bootloader @command{installer} command, such as @code{/dev/sda} or
32339 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
32340 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
32341 system, usually @file{/boot/efi}. For @code{grub-efi-netboot-bootloader},
32342 @code{target} should be the mount point corresponding to the TFTP root
32343 directory of your TFTP server.
32345 @item @code{menu-entries} (default: @code{()})
32346 A possibly empty list of @code{menu-entry} objects (see below), denoting
32347 entries to appear in the bootloader menu, in addition to the current
32348 system entry and the entry pointing to previous system generations.
32350 @item @code{default-entry} (default: @code{0})
32351 The index of the default boot menu entry. Index 0 is for the entry of the
32354 @item @code{timeout} (default: @code{5})
32355 The number of seconds to wait for keyboard input before booting. Set to
32356 0 to boot immediately, and to -1 to wait indefinitely.
32358 @cindex keyboard layout, for the bootloader
32359 @item @code{keyboard-layout} (default: @code{#f})
32360 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
32361 layout, usually US@tie{}English (``qwerty'').
32363 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
32367 This option is currently ignored by bootloaders other than @code{grub} and
32371 @item @code{theme} (default: @var{#f})
32372 The bootloader theme object describing the theme to use. If no theme
32373 is provided, some bootloaders might use a default theme, that's true
32376 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
32377 The output terminals used for the bootloader boot menu, as a list of
32378 symbols. GRUB accepts the values: @code{console}, @code{serial},
32379 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
32380 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
32381 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
32382 configuration,,, grub,GNU GRUB manual}).
32384 @item @code{terminal-inputs} (default: @code{'()})
32385 The input terminals used for the bootloader boot menu, as a list of
32386 symbols. For GRUB, the default is the native platform terminal as
32387 determined at run-time. GRUB accepts the values: @code{console},
32388 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
32389 @code{usb_keyboard}. This field corresponds to the GRUB variable
32390 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
32393 @item @code{serial-unit} (default: @code{#f})
32394 The serial unit used by the bootloader, as an integer from 0 to 3.
32395 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
32396 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
32398 @item @code{serial-speed} (default: @code{#f})
32399 The speed of the serial interface, as an integer. For GRUB, the
32400 default value is chosen at run-time; currently GRUB chooses
32401 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
32408 Should you want to list additional boot menu entries @i{via} the
32409 @code{menu-entries} field above, you will need to create them with the
32410 @code{menu-entry} form. For example, imagine you want to be able to
32411 boot another distro (hard to imagine!), you can define a menu entry
32416 (label "The Other Distro")
32417 (linux "/boot/old/vmlinux-2.6.32")
32418 (linux-arguments '("root=/dev/sda2"))
32419 (initrd "/boot/old/initrd"))
32424 @deftp {Data Type} menu-entry
32425 The type of an entry in the bootloader menu.
32430 The label to show in the menu---e.g., @code{"GNU"}.
32432 @item @code{linux} (default: @code{#f})
32433 The Linux kernel image to boot, for example:
32436 (file-append linux-libre "/bzImage")
32439 For GRUB, it is also possible to specify a device explicitly in the
32440 file path using GRUB's device naming convention (@pxref{Naming
32441 convention,,, grub, GNU GRUB manual}), for example:
32444 "(hd0,msdos1)/boot/vmlinuz"
32447 If the device is specified explicitly as above, then the @code{device}
32448 field is ignored entirely.
32450 @item @code{linux-arguments} (default: @code{()})
32451 The list of extra Linux kernel command-line arguments---e.g.,
32452 @code{("console=ttyS0")}.
32454 @item @code{initrd} (default: @code{#f})
32455 A G-Expression or string denoting the file name of the initial RAM disk
32456 to use (@pxref{G-Expressions}).
32458 @item @code{device} (default: @code{#f})
32459 The device where the kernel and initrd are to be found---i.e., for GRUB,
32460 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
32462 This may be a file system label (a string), a file system UUID (a
32463 bytevector, @pxref{File Systems}), or @code{#f}, in which case
32464 the bootloader will search the device containing the file specified by
32465 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
32466 must @emph{not} be an OS device name such as @file{/dev/sda1}.
32468 @item @code{multiboot-kernel} (default: @code{#f})
32469 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
32470 manual}). When this field is set, a Multiboot menu-entry is generated.
32474 (file-append mach "/boot/gnumach")
32477 @item @code{multiboot-arguments} (default: @code{()})
32478 The list of extra command-line arguments for the multiboot-kernel.
32480 @item @code{multiboot-modules} (default: @code{()})
32481 The list of commands for loading Multiboot modules. For example:
32484 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
32486 (list (file-append libc "/lib/ld.so.1") "exec"
32496 @c FIXME: Write documentation once it's stable.
32497 For now only GRUB has theme support. GRUB themes are created using
32498 the @code{grub-theme} form, which is not fully documented yet.
32500 @deftp {Data Type} grub-theme
32501 Data type representing the configuration of the GRUB theme.
32504 @item @code{gfxmode} (default: @code{'("auto")})
32505 The GRUB @code{gfxmode} to set (a list of screen resolution strings,
32506 @pxref{gfxmode,,, grub, GNU GRUB manual}).
32510 @deffn {Scheme Procedure} grub-theme
32511 Return the default GRUB theme used by the operating system if no
32512 @code{theme} field is specified in @code{bootloader-configuration}
32515 It comes with a fancy background image displaying the GNU and Guix
32519 For example, to override the default resolution, you may use something
32524 (bootloader-configuration
32527 (inherit (grub-theme))
32528 (gfxmode '("1024x786x32" "auto"))))))
32531 @node Invoking guix system
32532 @section Invoking @code{guix system}
32534 Once you have written an operating system declaration as seen in the
32535 previous section, it can be @dfn{instantiated} using the @command{guix
32536 system} command. The synopsis is:
32539 guix system @var{options}@dots{} @var{action} @var{file}
32542 @var{file} must be the name of a file containing an
32543 @code{operating-system} declaration. @var{action} specifies how the
32544 operating system is instantiated. Currently the following values are
32549 Display available service type definitions that match the given regular
32550 expressions, sorted by relevance:
32556 $ guix system search console
32557 name: console-fonts
32558 location: gnu/services/base.scm:806:2
32559 extends: shepherd-root
32560 description: Install the given fonts on the specified ttys (fonts are per
32561 + virtual console on GNU/Linux). The value of this service is a list of
32562 + tty/font pairs. The font can be the name of a font provided by the `kbd'
32563 + package or any valid argument to `setfont', as in this example:
32565 + '(("tty1" . "LatGrkCyr-8x16")
32566 + ("tty2" . (file-append
32568 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
32569 + ("tty3" . (file-append
32571 + "/share/consolefonts/ter-132n"))) ; for HDPI
32575 location: gnu/services/base.scm:1190:2
32576 extends: shepherd-root
32577 description: Provide console login using the `mingetty' program.
32581 location: gnu/services/base.scm:860:2
32583 description: Provide a console log-in service as specified by its
32584 + configuration value, a `login-configuration' object.
32590 As for @command{guix package --search}, the result is written in
32591 @code{recutils} format, which makes it easy to filter the output
32592 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
32595 Build the operating system described in @var{file}, activate it, and
32596 switch to it@footnote{This action (and the related actions
32597 @code{switch-generation} and @code{roll-back}) are usable only on
32598 systems already running Guix System.}.
32601 @c The paragraph below refers to the problem discussed at
32602 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
32603 It is highly recommended to run @command{guix pull} once before you run
32604 @command{guix system reconfigure} for the first time (@pxref{Invoking
32605 guix pull}). Failing to do that you would see an older version of Guix
32606 once @command{reconfigure} has completed.
32609 This effects all the configuration specified in @var{file}: user
32610 accounts, system services, global package list, setuid programs, etc.
32611 The command starts system services specified in @var{file} that are not
32612 currently running; if a service is currently running this command will
32613 arrange for it to be upgraded the next time it is stopped (e.g.@: by
32614 @code{herd stop X} or @code{herd restart X}).
32616 This command creates a new generation whose number is one greater than
32617 the current generation (as reported by @command{guix system
32618 list-generations}). If that generation already exists, it will be
32619 overwritten. This behavior mirrors that of @command{guix package}
32620 (@pxref{Invoking guix package}).
32622 It also adds a bootloader menu entry for the new OS configuration,
32623 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
32624 entries for older configurations to a submenu, allowing you to choose
32625 an older system generation at boot time should you need it.
32627 @cindex provenance tracking, of the operating system
32628 Upon completion, the new system is deployed under
32629 @file{/run/current-system}. This directory contains @dfn{provenance
32630 meta-data}: the list of channels in use (@pxref{Channels}) and
32631 @var{file} itself, when available. You can view it by running:
32634 guix system describe
32637 This information is useful should you later want to inspect how this
32638 particular generation was built. In fact, assuming @var{file} is
32639 self-contained, you can later rebuild generation @var{n} of your
32640 operating system with:
32643 guix time-machine \
32644 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
32645 system reconfigure \
32646 /var/guix/profiles/system-@var{n}-link/configuration.scm
32649 You can think of it as some sort of built-in version control! Your
32650 system is not just a binary artifact: @emph{it carries its own source}.
32651 @xref{Service Reference, @code{provenance-service-type}}, for more
32652 information on provenance tracking.
32654 By default, @command{reconfigure} @emph{prevents you from downgrading
32655 your system}, which could (re)introduce security vulnerabilities and
32656 also cause problems with ``stateful'' services such as database
32657 management systems. You can override that behavior by passing
32658 @option{--allow-downgrades}.
32660 @item switch-generation
32661 @cindex generations
32662 Switch to an existing system generation. This action atomically
32663 switches the system profile to the specified system generation. It
32664 also rearranges the system's existing bootloader menu entries. It
32665 makes the menu entry for the specified system generation the default,
32666 and it moves the entries for the other generations to a submenu, if
32667 supported by the bootloader being used. The next time the system
32668 boots, it will use the specified system generation.
32670 The bootloader itself is not being reinstalled when using this
32671 command. Thus, the installed bootloader is used with an updated
32672 configuration file.
32674 The target generation can be specified explicitly by its generation
32675 number. For example, the following invocation would switch to system
32679 guix system switch-generation 7
32682 The target generation can also be specified relative to the current
32683 generation with the form @code{+N} or @code{-N}, where @code{+3} means
32684 ``3 generations ahead of the current generation,'' and @code{-1} means
32685 ``1 generation prior to the current generation.'' When specifying a
32686 negative value such as @code{-1}, you must precede it with @code{--} to
32687 prevent it from being parsed as an option. For example:
32690 guix system switch-generation -- -1
32693 Currently, the effect of invoking this action is @emph{only} to switch
32694 the system profile to an existing generation and rearrange the
32695 bootloader menu entries. To actually start using the target system
32696 generation, you must reboot after running this action. In the future,
32697 it will be updated to do the same things as @command{reconfigure},
32698 like activating and deactivating services.
32700 This action will fail if the specified generation does not exist.
32703 @cindex rolling back
32704 Switch to the preceding system generation. The next time the system
32705 boots, it will use the preceding system generation. This is the inverse
32706 of @command{reconfigure}, and it is exactly the same as invoking
32707 @command{switch-generation} with an argument of @code{-1}.
32709 Currently, as with @command{switch-generation}, you must reboot after
32710 running this action to actually start using the preceding system
32713 @item delete-generations
32714 @cindex deleting system generations
32715 @cindex saving space
32716 Delete system generations, making them candidates for garbage collection
32717 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
32720 This works in the same way as @samp{guix package --delete-generations}
32721 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
32722 arguments, all system generations but the current one are deleted:
32725 guix system delete-generations
32728 You can also select the generations you want to delete. The example below
32729 deletes all the system generations that are more than two month old:
32732 guix system delete-generations 2m
32735 Running this command automatically reinstalls the bootloader with an updated
32736 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
32737 longer lists the generations that have been deleted.
32740 Build the derivation of the operating system, which includes all the
32741 configuration files and programs needed to boot and run the system.
32742 This action does not actually install anything.
32745 Populate the given directory with all the files necessary to run the
32746 operating system specified in @var{file}. This is useful for first-time
32747 installations of Guix System. For instance:
32750 guix system init my-os-config.scm /mnt
32753 copies to @file{/mnt} all the store items required by the configuration
32754 specified in @file{my-os-config.scm}. This includes configuration
32755 files, packages, and so on. It also creates other essential files
32756 needed for the system to operate correctly---e.g., the @file{/etc},
32757 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
32759 This command also installs bootloader on the target specified in
32760 @file{my-os-config}, unless the @option{--no-bootloader} option was
32764 @cindex virtual machine
32766 @anchor{guix system vm}
32767 Build a virtual machine that contains the operating system declared in
32768 @var{file}, and return a script to run that virtual machine (VM).
32771 The @code{vm} action and others below
32772 can use KVM support in the Linux-libre kernel. Specifically, if the
32773 machine has hardware virtualization support, the corresponding
32774 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
32775 must exist and be readable and writable by the user and by the
32776 build users of the daemon (@pxref{Build Environment Setup}).
32779 Arguments given to the script are passed to QEMU as in the example
32780 below, which enables networking and requests 1@tie{}GiB of RAM for the
32784 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
32787 The VM shares its store with the host system.
32789 Additional file systems can be shared between the host and the VM using
32790 the @option{--share} and @option{--expose} command-line options: the former
32791 specifies a directory to be shared with write access, while the latter
32792 provides read-only access to the shared directory.
32794 The example below creates a VM in which the user's home directory is
32795 accessible read-only, and where the @file{/exchange} directory is a
32796 read-write mapping of @file{$HOME/tmp} on the host:
32799 guix system vm my-config.scm \
32800 --expose=$HOME --share=$HOME/tmp=/exchange
32803 On GNU/Linux, the default is to boot directly to the kernel; this has
32804 the advantage of requiring only a very tiny root disk image since the
32805 store of the host can then be mounted.
32807 The @option{--full-boot} option forces a complete boot sequence, starting
32808 with the bootloader. This requires more disk space since a root image
32809 containing at least the kernel, initrd, and bootloader data files must
32810 be created. The @option{--image-size} option can be used to specify the
32813 @cindex System images, creation in various formats
32814 @cindex Creating system images in various formats
32816 @itemx docker-image
32817 Return a virtual machine, disk image, or Docker image of the operating
32818 system declared in @var{file} that stands alone. By default,
32819 @command{guix system} estimates the size of the image needed to store
32820 the system, but you can use the @option{--image-size} option to specify
32821 a value. Docker images are built to contain exactly what they need, so
32822 the @option{--image-size} option is ignored in the case of
32823 @code{docker-image}.
32825 @cindex image, creating disk images
32826 The @code{image} command can produce various image types. The
32827 image type can be selected using the @option{--image-type} option. It
32828 defaults to @code{efi-raw}. When its value is @code{iso9660}, the
32829 @option{--label} option can be used to specify a volume ID with
32830 @code{image}. By default, the root file system of a disk image is
32831 mounted non-volatile; the @option{--volatile} option can be provided to
32832 make it volatile instead. When using @code{image}, the bootloader
32833 installed on the generated image is taken from the provided
32834 @code{operating-system} definition. The following example demonstrates
32835 how to generate an image that uses the @code{grub-efi-bootloader}
32836 bootloader and boot it with QEMU:
32839 image=$(guix system image --image-type=qcow2 \
32840 gnu/system/examples/lightweight-desktop.tmpl)
32841 cp $image /tmp/my-image.qcow2
32842 chmod +w /tmp/my-image.qcow2
32843 qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
32844 -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
32847 When using the @code{efi-raw} image type, a raw disk image is produced;
32848 it can be copied as is to a USB stick, for instance. Assuming
32849 @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
32850 the image to it using the following command:
32853 # dd if=$(guix system image my-os.scm) of=/dev/sdc status=progress
32856 The @code{--list-image-types} command lists all the available image
32859 @cindex creating virtual machine images
32860 When using the @code{qcow2} image type, the returned image is in qcow2
32861 format, which the QEMU emulator can efficiently use. @xref{Running Guix
32862 in a VM}, for more information on how to run the image in a virtual
32863 machine. The @code{grub-bootloader} bootloader is always used
32864 independently of what is declared in the @code{operating-system} file
32865 passed as argument. This is to make it easier to work with QEMU, which
32866 uses the SeaBIOS BIOS by default, expecting a bootloader to be installed
32867 in the Master Boot Record (MBR).
32869 @cindex docker-image, creating docker images
32870 When using @code{docker-image}, a Docker image is produced. Guix builds
32871 the image from scratch, not from a pre-existing Docker base image. As a
32872 result, it contains @emph{exactly} what you define in the operating
32873 system configuration file. You can then load the image and launch a
32874 Docker container using commands like the following:
32877 image_id="`docker load < guix-system-docker-image.tar.gz`"
32878 container_id="`docker create $image_id`"
32879 docker start $container_id
32882 This command starts a new Docker container from the specified image. It
32883 will boot the Guix system in the usual manner, which means it will
32884 start any services you have defined in the operating system
32885 configuration. You can get an interactive shell running in the container
32886 using @command{docker exec}:
32889 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
32892 Depending on what you run in the Docker container, it
32893 may be necessary to give the container additional permissions. For
32894 example, if you intend to build software using Guix inside of the Docker
32895 container, you may need to pass the @option{--privileged} option to
32896 @code{docker create}.
32898 Last, the @option{--network} option applies to @command{guix system
32899 docker-image}: it produces an image where network is supposedly shared
32900 with the host, and thus without services like nscd or NetworkManager.
32903 Return a script to run the operating system declared in @var{file}
32904 within a container. Containers are a set of lightweight isolation
32905 mechanisms provided by the kernel Linux-libre. Containers are
32906 substantially less resource-demanding than full virtual machines since
32907 the kernel, shared objects, and other resources can be shared with the
32908 host system; this also means they provide thinner isolation.
32910 Currently, the script must be run as root in order to support more than
32911 a single user and group. The container shares its store with the host
32914 As with the @code{vm} action (@pxref{guix system vm}), additional file
32915 systems to be shared between the host and container can be specified
32916 using the @option{--share} and @option{--expose} options:
32919 guix system container my-config.scm \
32920 --expose=$HOME --share=$HOME/tmp=/exchange
32924 This option requires Linux-libre 3.19 or newer.
32929 @var{options} can contain any of the common build options (@pxref{Common
32930 Build Options}). In addition, @var{options} can contain one of the
32934 @item --expression=@var{expr}
32935 @itemx -e @var{expr}
32936 Consider the operating-system @var{expr} evaluates to.
32937 This is an alternative to specifying a file which evaluates to an
32939 This is used to generate the Guix system installer @pxref{Building the
32940 Installation Image}).
32942 @item --system=@var{system}
32943 @itemx -s @var{system}
32944 Attempt to build for @var{system} instead of the host system type.
32945 This works as per @command{guix build} (@pxref{Invoking guix build}).
32949 Return the derivation file name of the given operating system without
32952 @cindex provenance tracking, of the operating system
32953 @item --save-provenance
32954 As discussed above, @command{guix system init} and @command{guix system
32955 reconfigure} always save provenance information @i{via} a dedicated
32956 service (@pxref{Service Reference, @code{provenance-service-type}}).
32957 However, other commands don't do that by default. If you wish to, say,
32958 create a virtual machine image that contains provenance information, you
32962 guix system image -t qcow2 --save-provenance config.scm
32965 That way, the resulting image will effectively ``embed its own source''
32966 in the form of meta-data in @file{/run/current-system}. With that
32967 information, one can rebuild the image to make sure it really contains
32968 what it pretends to contain; or they could use that to derive a variant
32971 @item --image-type=@var{type}
32972 @itemx -t @var{type}
32973 For the @code{image} action, create an image with given @var{type}.
32975 When this option is omitted, @command{guix system} uses the
32976 @code{efi-raw} image type.
32978 @cindex ISO-9660 format
32979 @cindex CD image format
32980 @cindex DVD image format
32981 @option{--image-type=iso9660} produces an ISO-9660 image, suitable
32982 for burning on CDs and DVDs.
32984 @item --image-size=@var{size}
32985 For the @code{image} action, create an image of the given @var{size}.
32986 @var{size} may be a number of bytes, or it may include a unit as a
32987 suffix (@pxref{Block size, size specifications,, coreutils, GNU
32990 When this option is omitted, @command{guix system} computes an estimate
32991 of the image size as a function of the size of the system declared in
32996 For the @code{container} action, allow containers to access the host network,
32997 that is, do not create a network namespace.
32999 @item --root=@var{file}
33000 @itemx -r @var{file}
33001 Make @var{file} a symlink to the result, and register it as a garbage
33004 @item --skip-checks
33005 Skip pre-installation safety checks.
33007 By default, @command{guix system init} and @command{guix system
33008 reconfigure} perform safety checks: they make sure the file systems that
33009 appear in the @code{operating-system} declaration actually exist
33010 (@pxref{File Systems}), and that any Linux kernel modules that may be
33011 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
33012 RAM Disk}). Passing this option skips these tests altogether.
33014 @item --allow-downgrades
33015 Instruct @command{guix system reconfigure} to allow system downgrades.
33017 By default, @command{reconfigure} prevents you from downgrading your
33018 system. It achieves that by comparing the provenance info of your
33019 system (shown by @command{guix system describe}) with that of your
33020 @command{guix} command (shown by @command{guix describe}). If the
33021 commits for @command{guix} are not descendants of those used for your
33022 system, @command{guix system reconfigure} errors out. Passing
33023 @option{--allow-downgrades} allows you to bypass these checks.
33026 Make sure you understand its security implications before using
33027 @option{--allow-downgrades}.
33031 @cindex on-error strategy
33032 @cindex error strategy
33033 @item --on-error=@var{strategy}
33034 Apply @var{strategy} when an error occurs when reading @var{file}.
33035 @var{strategy} may be one of the following:
33038 @item nothing-special
33039 Report the error concisely and exit. This is the default strategy.
33042 Likewise, but also display a backtrace.
33045 Report the error and enter Guile's debugger. From there, you can run
33046 commands such as @code{,bt} to get a backtrace, @code{,locals} to
33047 display local variable values, and more generally inspect the state of the
33048 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
33049 a list of available debugging commands.
33053 Once you have built, configured, re-configured, and re-re-configured
33054 your Guix installation, you may find it useful to list the operating
33055 system generations available on disk---and that you can choose from the
33056 bootloader boot menu:
33061 Describe the current system generation: its file name, the kernel and
33062 bootloader used, etc., as well as provenance information when available.
33064 @item list-generations
33065 List a summary of each generation of the operating system available on
33066 disk, in a human-readable way. This is similar to the
33067 @option{--list-generations} option of @command{guix package}
33068 (@pxref{Invoking guix package}).
33070 Optionally, one can specify a pattern, with the same syntax that is used
33071 in @command{guix package --list-generations}, to restrict the list of
33072 generations displayed. For instance, the following command displays
33073 generations that are up to 10 days old:
33076 $ guix system list-generations 10d
33081 The @command{guix system} command has even more to offer! The following
33082 sub-commands allow you to visualize how your system services relate to
33085 @anchor{system-extension-graph}
33088 @item extension-graph
33089 Emit to standard output the @dfn{service
33090 extension graph} of the operating system defined in @var{file}
33091 (@pxref{Service Composition}, for more information on service
33092 extensions). By default the output is in Dot/Graphviz format, but you
33093 can choose a different format with @option{--graph-backend}, as with
33094 @command{guix graph} (@pxref{Invoking guix graph, @option{--backend}}):
33099 $ guix system extension-graph @var{file} | xdot -
33102 shows the extension relations among services.
33104 @anchor{system-shepherd-graph}
33105 @item shepherd-graph
33106 Emit to standard output the @dfn{dependency
33107 graph} of shepherd services of the operating system defined in
33108 @var{file}. @xref{Shepherd Services}, for more information and for an
33111 Again, the default output format is Dot/Graphviz, but you can pass
33112 @option{--graph-backend} to select a different one.
33116 @node Invoking guix deploy
33117 @section Invoking @code{guix deploy}
33119 We've already seen @code{operating-system} declarations used to manage a
33120 machine's configuration locally. Suppose you need to configure multiple
33121 machines, though---perhaps you're managing a service on the web that's
33122 comprised of several servers. @command{guix deploy} enables you to use those
33123 same @code{operating-system} declarations to manage multiple remote hosts at
33124 once as a logical ``deployment''.
33127 The functionality described in this section is still under development
33128 and is subject to change. Get in touch with us on
33129 @email{guix-devel@@gnu.org}!
33133 guix deploy @var{file}
33136 Such an invocation will deploy the machines that the code within @var{file}
33137 evaluates to. As an example, @var{file} might contain a definition like this:
33140 ;; This is a Guix deployment of a "bare bones" setup, with
33141 ;; no X11 display server, to a machine with an SSH daemon
33142 ;; listening on localhost:2222. A configuration such as this
33143 ;; may be appropriate for virtual machine with ports
33144 ;; forwarded to the host's loopback interface.
33146 (use-service-modules networking ssh)
33147 (use-package-modules bootloaders)
33151 (host-name "gnu-deployed")
33152 (timezone "Etc/UTC")
33153 (bootloader (bootloader-configuration
33154 (bootloader grub-bootloader)
33155 (target "/dev/vda")
33156 (terminal-outputs '(console))))
33157 (file-systems (cons (file-system
33159 (device "/dev/vda1")
33161 %base-file-systems))
33163 (append (list (service dhcp-client-service-type)
33164 (service openssh-service-type
33165 (openssh-configuration
33166 (permit-root-login #t)
33167 (allow-empty-passwords? #t))))
33171 (operating-system %system)
33172 (environment managed-host-environment-type)
33173 (configuration (machine-ssh-configuration
33174 (host-name "localhost")
33175 (system "x86_64-linux")
33177 (identity "./id_rsa")
33181 The file should evaluate to a list of @var{machine} objects. This example,
33182 upon being deployed, will create a new generation on the remote system
33183 realizing the @code{operating-system} declaration @code{%system}.
33184 @code{environment} and @code{configuration} specify how the machine should be
33185 provisioned---that is, how the computing resources should be created and
33186 managed. The above example does not create any resources, as a
33187 @code{'managed-host} is a machine that is already running the Guix system and
33188 available over the network. This is a particularly simple case; a more
33189 complex deployment may involve, for example, starting virtual machines through
33190 a Virtual Private Server (VPS) provider. In such a case, a different
33191 @var{environment} type would be used.
33193 Do note that you first need to generate a key pair on the coordinator machine
33194 to allow the daemon to export signed archives of files from the store
33195 (@pxref{Invoking guix archive}), though this step is automatic on Guix
33199 # guix archive --generate-key
33203 Each target machine must authorize the key of the master machine so that it
33204 accepts store items it receives from the coordinator:
33207 # guix archive --authorize < coordinator-public-key.txt
33210 @code{user}, in this example, specifies the name of the user account to log in
33211 as to perform the deployment. Its default value is @code{root}, but root
33212 login over SSH may be forbidden in some cases. To work around this,
33213 @command{guix deploy} can log in as an unprivileged user and employ
33214 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
33215 currently installed on the remote and can be invoked non-interactively as
33216 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
33217 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
33218 be accomplished with the following operating system configuration snippet:
33222 (gnu system)) ;for %sudoers-specification
33224 (define %user "username")
33229 (plain-file "sudoers"
33230 (string-append (plain-file-content %sudoers-specification)
33231 (format #f "~a ALL = NOPASSWD: ALL~%"
33236 For more information regarding the format of the @file{sudoers} file,
33237 consult @command{man sudoers}.
33239 @deftp {Data Type} machine
33240 This is the data type representing a single machine in a heterogeneous Guix
33244 @item @code{operating-system}
33245 The object of the operating system configuration to deploy.
33247 @item @code{environment}
33248 An @code{environment-type} describing how the machine should be provisioned.
33250 @item @code{configuration} (default: @code{#f})
33251 An object describing the configuration for the machine's @code{environment}.
33252 If the @code{environment} has a default configuration, @code{#f} may be used.
33253 If @code{#f} is used for an environment with no default configuration,
33254 however, an error will be thrown.
33258 @deftp {Data Type} machine-ssh-configuration
33259 This is the data type representing the SSH client parameters for a machine
33260 with an @code{environment} of @code{managed-host-environment-type}.
33263 @item @code{host-name}
33264 @item @code{build-locally?} (default: @code{#t})
33265 If false, system derivations will be built on the machine being deployed to.
33266 @item @code{system}
33267 The system type describing the architecture of the machine being deployed
33268 to---e.g., @code{"x86_64-linux"}.
33269 @item @code{authorize?} (default: @code{#t})
33270 If true, the coordinator's signing key will be added to the remote's ACL
33272 @item @code{port} (default: @code{22})
33273 @item @code{user} (default: @code{"root"})
33274 @item @code{identity} (default: @code{#f})
33275 If specified, the path to the SSH private key to use to authenticate with the
33278 @item @code{host-key} (default: @code{#f})
33279 This should be the SSH host key of the machine, which looks like this:
33282 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
33285 When @code{host-key} is @code{#f}, the server is authenticated against
33286 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
33289 @item @code{allow-downgrades?} (default: @code{#f})
33290 Whether to allow potential downgrades.
33292 Like @command{guix system reconfigure}, @command{guix deploy} compares
33293 the channel commits currently deployed on the remote host (as returned
33294 by @command{guix system describe}) to those currently in use (as
33295 returned by @command{guix describe}) to determine whether commits
33296 currently in use are descendants of those deployed. When this is not
33297 the case and @code{allow-downgrades?} is false, it raises an error.
33298 This ensures you do not accidentally downgrade remote machines.
33302 @deftp {Data Type} digital-ocean-configuration
33303 This is the data type describing the Droplet that should be created for a
33304 machine with an @code{environment} of @code{digital-ocean-environment-type}.
33307 @item @code{ssh-key}
33308 The path to the SSH private key to use to authenticate with the remote
33309 host. In the future, this field may not exist.
33311 A list of string ``tags'' that uniquely identify the machine. Must be given
33312 such that no two machines in the deployment have the same set of tags.
33313 @item @code{region}
33314 A Digital Ocean region slug, such as @code{"nyc3"}.
33316 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
33317 @item @code{enable-ipv6?}
33318 Whether or not the droplet should be created with IPv6 networking.
33322 @node Running Guix in a VM
33323 @section Running Guix in a Virtual Machine
33325 @cindex virtual machine
33326 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
33328 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
33329 This image is a compressed image in QCOW format. You will first need to
33330 decompress with @command{xz -d}, and then you can pass it to an emulator such
33331 as QEMU (see below for details).
33333 This image boots the Xfce graphical environment and it contains some
33334 commonly used tools. You can install more software in the image by running
33335 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
33336 also reconfigure the system based on its initial configuration file available
33337 as @file{/run/current-system/configuration.scm} (@pxref{Using the
33338 Configuration System}).
33340 Instead of using this pre-built image, one can also build their own virtual
33341 machine image using @command{guix system vm-image} (@pxref{Invoking guix
33342 system}). The returned image is in qcow2 format, which the
33343 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
33346 If you built your own image, you must copy it out of the store
33347 (@pxref{The Store}) and give yourself permission to write to the copy
33348 before you can use it. When invoking QEMU, you must choose a system
33349 emulator that is suitable for your hardware platform. Here is a minimal
33350 QEMU invocation that will boot the result of @command{guix system
33351 image -t qcow2} on x86_64 hardware:
33354 $ qemu-system-x86_64 \
33355 -nic user,model=virtio-net-pci \
33356 -enable-kvm -m 1024 \
33357 -device virtio-blk,drive=myhd \
33358 -drive if=none,file=/tmp/qemu-image,id=myhd
33361 Here is what each of these options means:
33364 @item qemu-system-x86_64
33365 This specifies the hardware platform to emulate. This should match the
33368 @item -nic user,model=virtio-net-pci
33369 Enable the unprivileged user-mode network stack. The guest OS can
33370 access the host but not vice versa. This is the simplest way to get the
33371 guest OS online. @code{model} specifies which network device to emulate:
33372 @code{virtio-net-pci} is a special device made for virtualized operating
33373 systems and recommended for most uses. Assuming your hardware platform is
33374 x86_64, you can get a list of available NIC models by running
33375 @command{qemu-system-x86_64 -nic model=help}.
33378 If your system has hardware virtualization extensions, enabling the
33379 virtual machine support (KVM) of the Linux kernel will make things run
33382 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
33384 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
33385 which may be insufficient for some operations.
33387 @item -device virtio-blk,drive=myhd
33388 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
33389 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
33390 better performance than if it were emulating a complete disk drive. See the
33391 QEMU and KVM documentation for more info.
33393 @item -drive if=none,file=/tmp/qemu-image,id=myhd
33394 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
33395 store of the ``myhd'' drive.
33398 The default @command{run-vm.sh} script that is returned by an invocation of
33399 @command{guix system vm} does not add a @command{-nic user} flag by default.
33400 To get network access from within the vm add the @code{(dhcp-client-service)}
33401 to your system definition and start the VM using
33402 @command{`guix system vm config.scm` -nic user}. An important caveat of using
33403 @command{-nic user} for networking is that @command{ping} will not work, because
33404 it uses the ICMP protocol. You'll have to use a different command to check for
33405 network connectivity, for example @command{guix download}.
33407 @subsection Connecting Through SSH
33411 To enable SSH inside a VM you need to add an SSH server like
33412 @code{openssh-service-type} to your VM (@pxref{Networking Services,
33413 @code{openssh-service-type}}). In addition you need to forward the SSH port,
33414 22 by default, to the host. You can do this with
33417 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
33420 To connect to the VM you can run
33423 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
33426 The @command{-p} tells @command{ssh} the port you want to connect to.
33427 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
33428 every time you modify your @command{config.scm} file and the
33429 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
33430 connection to an unknown host every time you connect.
33432 @subsection Using @command{virt-viewer} with Spice
33434 As an alternative to the default @command{qemu} graphical client you can
33435 use the @command{remote-viewer} from the @command{virt-viewer} package. To
33436 connect pass the @command{-spice port=5930,disable-ticketing} flag to
33437 @command{qemu}. See previous section for further information on how to do this.
33439 Spice also allows you to do some nice stuff like share your clipboard with your
33440 VM@. To enable that you'll also have to pass the following flags to @command{qemu}:
33443 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
33444 -chardev spicevmc,name=vdagent,id=vdagent
33445 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
33446 name=com.redhat.spice.0
33449 You'll also need to add the @code{(spice-vdagent-service)} to your
33450 system definition (@pxref{Miscellaneous Services, Spice service}).
33452 @node Defining Services
33453 @section Defining Services
33455 The previous sections show the available services and how one can combine
33456 them in an @code{operating-system} declaration. But how do we define
33457 them in the first place? And what is a service anyway?
33460 * Service Composition:: The model for composing services.
33461 * Service Types and Services:: Types and services.
33462 * Service Reference:: API reference.
33463 * Shepherd Services:: A particular type of service.
33466 @node Service Composition
33467 @subsection Service Composition
33471 Here we define a @dfn{service} as, broadly, something that extends the
33472 functionality of the operating system. Often a service is a process---a
33473 @dfn{daemon}---started when the system boots: a secure shell server, a
33474 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
33475 whose execution can be triggered by another daemon---e.g., an FTP server
33476 started by @command{inetd} or a D-Bus service activated by
33477 @command{dbus-daemon}. Occasionally, a service does not map to a
33478 daemon. For instance, the ``account'' service collects user accounts
33479 and makes sure they exist when the system runs; the ``udev'' service
33480 collects device management rules and makes them available to the eudev
33481 daemon; the @file{/etc} service populates the @file{/etc} directory
33484 @cindex service extensions
33485 Guix system services are connected by @dfn{extensions}. For instance, the
33486 secure shell service @emph{extends} the Shepherd---the
33487 initialization system, running as PID@tie{}1---by giving it the command
33488 lines to start and stop the secure shell daemon (@pxref{Networking
33489 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
33490 service by passing it its @file{.service} specification, and extends the
33491 udev service by passing it device management rules (@pxref{Desktop
33492 Services, @code{upower-service}}); the Guix daemon service extends the
33493 Shepherd by passing it the command lines to start and stop the daemon,
33494 and extends the account service by passing it a list of required build
33495 user accounts (@pxref{Base Services}).
33497 All in all, services and their ``extends'' relations form a directed
33498 acyclic graph (DAG). If we represent services as boxes and extensions
33499 as arrows, a typical system might provide something like this:
33501 @image{images/service-graph,,5in,Typical service extension graph.}
33503 @cindex system service
33504 At the bottom, we see the @dfn{system service}, which produces the
33505 directory containing everything to run and boot the system, as returned
33506 by the @command{guix system build} command. @xref{Service Reference},
33507 to learn about the other service types shown here.
33508 @xref{system-extension-graph, the @command{guix system extension-graph}
33509 command}, for information on how to generate this representation for a
33510 particular operating system definition.
33512 @cindex service types
33513 Technically, developers can define @dfn{service types} to express these
33514 relations. There can be any number of services of a given type on the
33515 system---for instance, a system running two instances of the GNU secure
33516 shell server (lsh) has two instances of @code{lsh-service-type}, with
33517 different parameters.
33519 The following section describes the programming interface for service
33520 types and services.
33522 @node Service Types and Services
33523 @subsection Service Types and Services
33525 A @dfn{service type} is a node in the DAG described above. Let us start
33526 with a simple example, the service type for the Guix build daemon
33527 (@pxref{Invoking guix-daemon}):
33530 (define guix-service-type
33534 (list (service-extension shepherd-root-service-type guix-shepherd-service)
33535 (service-extension account-service-type guix-accounts)
33536 (service-extension activation-service-type guix-activation)))
33537 (default-value (guix-configuration))))
33541 It defines three things:
33545 A name, whose sole purpose is to make inspection and debugging easier.
33548 A list of @dfn{service extensions}, where each extension designates the
33549 target service type and a procedure that, given the parameters of the
33550 service, returns a list of objects to extend the service of that type.
33552 Every service type has at least one service extension. The only
33553 exception is the @dfn{boot service type}, which is the ultimate service.
33556 Optionally, a default value for instances of this type.
33559 In this example, @code{guix-service-type} extends three services:
33562 @item shepherd-root-service-type
33563 The @code{guix-shepherd-service} procedure defines how the Shepherd
33564 service is extended. Namely, it returns a @code{<shepherd-service>}
33565 object that defines how @command{guix-daemon} is started and stopped
33566 (@pxref{Shepherd Services}).
33568 @item account-service-type
33569 This extension for this service is computed by @code{guix-accounts},
33570 which returns a list of @code{user-group} and @code{user-account}
33571 objects representing the build user accounts (@pxref{Invoking
33574 @item activation-service-type
33575 Here @code{guix-activation} is a procedure that returns a gexp, which is
33576 a code snippet to run at ``activation time''---e.g., when the service is
33580 A service of this type is instantiated like this:
33583 (service guix-service-type
33584 (guix-configuration
33586 (extra-options '("--gc-keep-derivations"))))
33589 The second argument to the @code{service} form is a value representing
33590 the parameters of this specific service instance.
33591 @xref{guix-configuration-type, @code{guix-configuration}}, for
33592 information about the @code{guix-configuration} data type. When the
33593 value is omitted, the default value specified by
33594 @code{guix-service-type} is used:
33597 (service guix-service-type)
33600 @code{guix-service-type} is quite simple because it extends other
33601 services but is not extensible itself.
33603 @c @subsubsubsection Extensible Service Types
33605 The service type for an @emph{extensible} service looks like this:
33608 (define udev-service-type
33609 (service-type (name 'udev)
33611 (list (service-extension shepherd-root-service-type
33612 udev-shepherd-service)))
33614 (compose concatenate) ;concatenate the list of rules
33615 (extend (lambda (config rules)
33617 (($ <udev-configuration> udev initial-rules)
33618 (udev-configuration
33619 (udev udev) ;the udev package to use
33620 (rules (append initial-rules rules)))))))))
33623 This is the service type for the
33624 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
33625 management daemon}. Compared to the previous example, in addition to an
33626 extension of @code{shepherd-root-service-type}, we see two new fields:
33630 This is the procedure to @dfn{compose} the list of extensions to
33631 services of this type.
33633 Services can extend the udev service by passing it lists of rules; we
33634 compose those extensions simply by concatenating them.
33637 This procedure defines how the value of the service is @dfn{extended} with
33638 the composition of the extensions.
33640 Udev extensions are composed into a list of rules, but the udev service
33641 value is itself a @code{<udev-configuration>} record. So here, we
33642 extend that record by appending the list of rules it contains to the
33643 list of contributed rules.
33646 This is a string giving an overview of the service type. The string can
33647 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
33648 @command{guix system search} command searches these strings and displays
33649 them (@pxref{Invoking guix system}).
33652 There can be only one instance of an extensible service type such as
33653 @code{udev-service-type}. If there were more, the
33654 @code{service-extension} specifications would be ambiguous.
33656 Still here? The next section provides a reference of the programming
33657 interface for services.
33659 @node Service Reference
33660 @subsection Service Reference
33662 We have seen an overview of service types (@pxref{Service Types and
33663 Services}). This section provides a reference on how to manipulate
33664 services and service types. This interface is provided by the
33665 @code{(gnu services)} module.
33667 @deffn {Scheme Procedure} service @var{type} [@var{value}]
33668 Return a new service of @var{type}, a @code{<service-type>} object (see
33669 below). @var{value} can be any object; it represents the parameters of
33670 this particular service instance.
33672 When @var{value} is omitted, the default value specified by @var{type}
33673 is used; if @var{type} does not specify a default value, an error is
33676 For instance, this:
33679 (service openssh-service-type)
33683 is equivalent to this:
33686 (service openssh-service-type
33687 (openssh-configuration))
33690 In both cases the result is an instance of @code{openssh-service-type}
33691 with the default configuration.
33694 @deffn {Scheme Procedure} service? @var{obj}
33695 Return true if @var{obj} is a service.
33698 @deffn {Scheme Procedure} service-kind @var{service}
33699 Return the type of @var{service}---i.e., a @code{<service-type>} object.
33702 @deffn {Scheme Procedure} service-value @var{service}
33703 Return the value associated with @var{service}. It represents its
33707 Here is an example of how a service is created and manipulated:
33711 (service nginx-service-type
33712 (nginx-configuration
33714 (log-directory log-directory)
33715 (run-directory run-directory)
33716 (file config-file))))
33721 (eq? (service-kind s) nginx-service-type)
33725 The @code{modify-services} form provides a handy way to change the
33726 parameters of some of the services of a list such as
33727 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
33728 evaluates to a list of services. Of course, you could always use
33729 standard list combinators such as @code{map} and @code{fold} to do that
33730 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
33731 @code{modify-services} simply provides a more concise form for this
33734 @deffn {Scheme Syntax} modify-services @var{services} @
33735 (@var{type} @var{variable} => @var{body}) @dots{}
33737 Modify the services listed in @var{services} according to the given
33738 clauses. Each clause has the form:
33741 (@var{type} @var{variable} => @var{body})
33744 where @var{type} is a service type---e.g.,
33745 @code{guix-service-type}---and @var{variable} is an identifier that is
33746 bound within the @var{body} to the service parameters---e.g., a
33747 @code{guix-configuration} instance---of the original service of that
33750 The @var{body} should evaluate to the new service parameters, which will
33751 be used to configure the new service. This new service will replace the
33752 original in the resulting list. Because a service's service parameters
33753 are created using @code{define-record-type*}, you can write a succinct
33754 @var{body} that evaluates to the new service parameters by using the
33755 @code{inherit} feature that @code{define-record-type*} provides.
33757 @xref{Using the Configuration System}, for example usage.
33761 Next comes the programming interface for service types. This is
33762 something you want to know when writing new service definitions, but not
33763 necessarily when simply looking for ways to customize your
33764 @code{operating-system} declaration.
33766 @deftp {Data Type} service-type
33767 @cindex service type
33768 This is the representation of a @dfn{service type} (@pxref{Service Types
33773 This is a symbol, used only to simplify inspection and debugging.
33775 @item @code{extensions}
33776 A non-empty list of @code{<service-extension>} objects (see below).
33778 @item @code{compose} (default: @code{#f})
33779 If this is @code{#f}, then the service type denotes services that cannot
33780 be extended---i.e., services that do not receive ``values'' from other
33783 Otherwise, it must be a one-argument procedure. The procedure is called
33784 by @code{fold-services} and is passed a list of values collected from
33785 extensions. It may return any single value.
33787 @item @code{extend} (default: @code{#f})
33788 If this is @code{#f}, services of this type cannot be extended.
33790 Otherwise, it must be a two-argument procedure: @code{fold-services}
33791 calls it, passing it the initial value of the service as the first
33792 argument and the result of applying @code{compose} to the extension
33793 values as the second argument. It must return a value that is a valid
33794 parameter value for the service instance.
33796 @item @code{description}
33797 This is a string, possibly using Texinfo markup, describing in a couple
33798 of sentences what the service is about. This string allows users to
33799 find about the service through @command{guix system search}
33800 (@pxref{Invoking guix system}).
33802 @item @code{default-value} (default: @code{&no-default-value})
33803 The default value associated for instances of this service type. This
33804 allows users to use the @code{service} form without its second argument:
33807 (service @var{type})
33810 The returned service in this case has the default value specified by
33814 @xref{Service Types and Services}, for examples.
33817 @deffn {Scheme Procedure} service-extension @var{target-type} @
33819 Return a new extension for services of type @var{target-type}.
33820 @var{compute} must be a one-argument procedure: @code{fold-services}
33821 calls it, passing it the value associated with the service that provides
33822 the extension; it must return a valid value for the target service.
33825 @deffn {Scheme Procedure} service-extension? @var{obj}
33826 Return true if @var{obj} is a service extension.
33829 Occasionally, you might want to simply extend an existing service. This
33830 involves creating a new service type and specifying the extension of
33831 interest, which can be verbose; the @code{simple-service} procedure
33832 provides a shorthand for this.
33834 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
33835 Return a service that extends @var{target} with @var{value}. This works
33836 by creating a singleton service type @var{name}, of which the returned
33837 service is an instance.
33839 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
33843 (simple-service 'my-mcron-job mcron-service-type
33844 #~(job '(next-hour (3)) "guix gc -F 2G"))
33848 At the core of the service abstraction lies the @code{fold-services}
33849 procedure, which is responsible for ``compiling'' a list of services
33850 down to a single directory that contains everything needed to boot and
33851 run the system---the directory shown by the @command{guix system build}
33852 command (@pxref{Invoking guix system}). In essence, it propagates
33853 service extensions down the service graph, updating each node parameters
33854 on the way, until it reaches the root node.
33856 @deffn {Scheme Procedure} fold-services @var{services} @
33857 [#:target-type @var{system-service-type}]
33858 Fold @var{services} by propagating their extensions down to the root of
33859 type @var{target-type}; return the root service adjusted accordingly.
33862 Lastly, the @code{(gnu services)} module also defines several essential
33863 service types, some of which are listed below.
33865 @defvr {Scheme Variable} system-service-type
33866 This is the root of the service graph. It produces the system directory
33867 as returned by the @command{guix system build} command.
33870 @defvr {Scheme Variable} boot-service-type
33871 The type of the ``boot service'', which produces the @dfn{boot script}.
33872 The boot script is what the initial RAM disk runs when booting.
33875 @defvr {Scheme Variable} etc-service-type
33876 The type of the @file{/etc} service. This service is used to create
33877 files under @file{/etc} and can be extended by
33878 passing it name/file tuples such as:
33881 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
33884 In this example, the effect would be to add an @file{/etc/issue} file
33885 pointing to the given file.
33888 @defvr {Scheme Variable} setuid-program-service-type
33889 Type for the ``setuid-program service''. This service collects lists of
33890 executable file names, passed as gexps, and adds them to the set of
33891 setuid-root programs on the system (@pxref{Setuid Programs}).
33894 @defvr {Scheme Variable} profile-service-type
33895 Type of the service that populates the @dfn{system profile}---i.e., the
33896 programs under @file{/run/current-system/profile}. Other services can
33897 extend it by passing it lists of packages to add to the system profile.
33900 @cindex provenance tracking, of the operating system
33901 @anchor{provenance-service-type}
33902 @defvr {Scheme Variable} provenance-service-type
33903 This is the type of the service that records @dfn{provenance meta-data}
33904 in the system itself. It creates several files under
33905 @file{/run/current-system}:
33909 This is a ``channel file'' that can be passed to @command{guix pull -C}
33910 or @command{guix time-machine -C}, and which describes the channels used
33911 to build the system, if that information was available
33912 (@pxref{Channels}).
33914 @item configuration.scm
33915 This is the file that was passed as the value for this
33916 @code{provenance-service-type} service. By default, @command{guix
33917 system reconfigure} automatically passes the OS configuration file it
33918 received on the command line.
33921 This contains the same information as the two other files but in a
33922 format that is more readily processable.
33925 In general, these two pieces of information (channels and configuration
33926 file) are enough to reproduce the operating system ``from source''.
33929 This information is necessary to rebuild your operating system, but it
33930 is not always sufficient. In particular, @file{configuration.scm}
33931 itself is insufficient if it is not self-contained---if it refers to
33932 external Guile modules or to extra files. If you want
33933 @file{configuration.scm} to be self-contained, we recommend that modules
33934 or files it refers to be part of a channel.
33936 Besides, provenance meta-data is ``silent'' in the sense that it does
33937 not change the bits contained in your system, @emph{except for the
33938 meta-data bits themselves}. Two different OS configurations or sets of
33939 channels can lead to the same system, bit-for-bit; when
33940 @code{provenance-service-type} is used, these two systems will have
33941 different meta-data and thus different store file names, which makes
33942 comparison less trivial.
33945 This service is automatically added to your operating system
33946 configuration when you use @command{guix system reconfigure},
33947 @command{guix system init}, or @command{guix deploy}.
33950 @node Shepherd Services
33951 @subsection Shepherd Services
33953 @cindex shepherd services
33955 @cindex init system
33956 The @code{(gnu services shepherd)} module provides a way to define
33957 services managed by the GNU@tie{}Shepherd, which is the
33958 initialization system---the first process that is started when the
33959 system boots, also known as PID@tie{}1
33960 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
33962 Services in the Shepherd can depend on each other. For instance, the
33963 SSH daemon may need to be started after the syslog daemon has been
33964 started, which in turn can only happen once all the file systems have
33965 been mounted. The simple operating system defined earlier (@pxref{Using
33966 the Configuration System}) results in a service graph like this:
33968 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
33970 You can actually generate such a graph for any operating system
33971 definition using the @command{guix system shepherd-graph} command
33972 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
33974 The @code{%shepherd-root-service} is a service object representing
33975 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
33976 by passing it lists of @code{<shepherd-service>} objects.
33978 @deftp {Data Type} shepherd-service
33979 The data type representing a service managed by the Shepherd.
33982 @item @code{provision}
33983 This is a list of symbols denoting what the service provides.
33985 These are the names that may be passed to @command{herd start},
33986 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
33987 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
33988 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
33990 @item @code{requirement} (default: @code{'()})
33991 List of symbols denoting the Shepherd services this one depends on.
33993 @cindex one-shot services, for the Shepherd
33994 @item @code{one-shot?} (default: @code{#f})
33995 Whether this service is @dfn{one-shot}. One-shot services stop immediately
33996 after their @code{start} action has completed. @xref{Slots of services,,,
33997 shepherd, The GNU Shepherd Manual}, for more info.
33999 @item @code{respawn?} (default: @code{#t})
34000 Whether to restart the service when it stops, for instance when the
34001 underlying process dies.
34004 @itemx @code{stop} (default: @code{#~(const #f)})
34005 The @code{start} and @code{stop} fields refer to the Shepherd's
34006 facilities to start and stop processes (@pxref{Service De- and
34007 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
34008 G-expressions that get expanded in the Shepherd configuration file
34009 (@pxref{G-Expressions}).
34011 @item @code{actions} (default: @code{'()})
34012 @cindex actions, of Shepherd services
34013 This is a list of @code{shepherd-action} objects (see below) defining
34014 @dfn{actions} supported by the service, in addition to the standard
34015 @code{start} and @code{stop} actions. Actions listed here become available as
34016 @command{herd} sub-commands:
34019 herd @var{action} @var{service} [@var{arguments}@dots{}]
34022 @item @code{auto-start?} (default: @code{#t})
34023 Whether this service should be started automatically by the Shepherd. If it
34024 is @code{#f} the service has to be started manually with @code{herd start}.
34026 @item @code{documentation}
34027 A documentation string, as shown when running:
34030 herd doc @var{service-name}
34033 where @var{service-name} is one of the symbols in @code{provision}
34034 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
34036 @item @code{modules} (default: @code{%default-modules})
34037 This is the list of modules that must be in scope when @code{start} and
34038 @code{stop} are evaluated.
34043 @deftp {Data Type} shepherd-action
34044 This is the data type that defines additional actions implemented by a
34045 Shepherd service (see above).
34049 Symbol naming the action.
34051 @item documentation
34052 This is a documentation string for the action. It can be viewed by running:
34055 herd doc @var{service} action @var{action}
34059 This should be a gexp that evaluates to a procedure of at least one argument,
34060 which is the ``running value'' of the service (@pxref{Slots of services,,,
34061 shepherd, The GNU Shepherd Manual}).
34064 The following example defines an action called @code{say-hello} that kindly
34070 (documentation "Say hi!")
34071 (procedure #~(lambda (running . args)
34072 (format #t "Hello, friend! arguments: ~s\n"
34077 Assuming this action is added to the @code{example} service, then you can do:
34080 # herd say-hello example
34081 Hello, friend! arguments: ()
34082 # herd say-hello example a b c
34083 Hello, friend! arguments: ("a" "b" "c")
34086 This, as you can see, is a fairly sophisticated way to say hello.
34087 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
34091 @defvr {Scheme Variable} shepherd-root-service-type
34092 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
34094 This is the service type that extensions target when they want to create
34095 shepherd services (@pxref{Service Types and Services}, for an example).
34096 Each extension must pass a list of @code{<shepherd-service>}. Its
34097 value must be a @code{shepherd-configuration}, as described below.
34100 @deftp {Data Type} shepherd-configuration
34101 This data type represents the Shepherd's configuration.
34104 @item shepherd (default: @code{shepherd})
34105 The Shepherd package to use.
34107 @item services (default: @code{'()})
34108 A list of @code{<shepherd-service>} to start.
34109 You should probably use the service extension
34110 mechanism instead (@pxref{Shepherd Services}).
34114 The following example specifies the Shepherd package for the operating
34120 (services (append (list openssh-service-type))
34124 ;; Use own Shepherd package.
34125 (essential-services
34126 (modify-services (operating-system-default-essential-services
34127 this-operating-system)
34128 (shepherd-root-service-type config => (shepherd-configuration
34130 (shepherd my-shepherd))))))
34133 @defvr {Scheme Variable} %shepherd-root-service
34134 This service represents PID@tie{}1.
34138 @node Documentation
34139 @chapter Documentation
34141 @cindex documentation, searching for
34142 @cindex searching for documentation
34143 @cindex Info, documentation format
34145 @cindex manual pages
34146 In most cases packages installed with Guix come with documentation.
34147 There are two main documentation formats: ``Info'', a browseable
34148 hypertext format used for GNU software, and ``manual pages'' (or ``man
34149 pages''), the linear documentation format traditionally found on Unix.
34150 Info manuals are accessed with the @command{info} command or with Emacs,
34151 and man pages are accessed using @command{man}.
34153 You can look for documentation of software installed on your system by
34154 keyword. For example, the following command searches for information
34155 about ``TLS'' in Info manuals:
34159 "(emacs)Network Security" -- STARTTLS
34160 "(emacs)Network Security" -- TLS
34161 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
34162 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
34167 The command below searches for the same keyword in man pages:
34171 SSL (7) - OpenSSL SSL/TLS library
34172 certtool (1) - GnuTLS certificate tool
34176 These searches are purely local to your computer so you have the
34177 guarantee that documentation you find corresponds to what you have
34178 actually installed, you can access it off-line, and your privacy is
34181 Once you have these results, you can view the relevant documentation by
34185 $ info "(gnutls)Core TLS API"
34195 Info manuals contain sections and indices as well as hyperlinks like
34196 those found in Web pages. The @command{info} reader (@pxref{Top, Info
34197 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
34198 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
34199 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
34200 Introduction}, for an introduction to Info navigation.
34202 @node Installing Debugging Files
34203 @chapter Installing Debugging Files
34205 @cindex debugging files
34206 Program binaries, as produced by the GCC compilers for instance, are
34207 typically written in the ELF format, with a section containing
34208 @dfn{debugging information}. Debugging information is what allows the
34209 debugger, GDB, to map binary code to source code; it is required to
34210 debug a compiled program in good conditions.
34212 This chapter explains how to use separate debug info when packages
34213 provide it, and how to rebuild packages with debug info when it's
34217 * Separate Debug Info:: Installing 'debug' outputs.
34218 * Rebuilding Debug Info:: Building missing debug info.
34221 @node Separate Debug Info
34222 @section Separate Debug Info
34224 The problem with debugging information is that is takes up a fair amount
34225 of disk space. For example, debugging information for the GNU C Library
34226 weighs in at more than 60 MiB@. Thus, as a user, keeping all the
34227 debugging info of all the installed programs is usually not an option.
34228 Yet, space savings should not come at the cost of an impediment to
34229 debugging---especially in the GNU system, which should make it easier
34230 for users to exert their computing freedom (@pxref{GNU Distribution}).
34232 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
34233 mechanism that allows users to get the best of both worlds: debugging
34234 information can be stripped from the binaries and stored in separate
34235 files. GDB is then able to load debugging information from those files,
34236 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
34239 The GNU distribution takes advantage of this by storing debugging
34240 information in the @code{lib/debug} sub-directory of a separate package
34241 output unimaginatively called @code{debug} (@pxref{Packages with
34242 Multiple Outputs}). Users can choose to install the @code{debug} output
34243 of a package when they need it. For instance, the following command
34244 installs the debugging information for the GNU C Library and for GNU
34248 guix install glibc:debug guile:debug
34251 GDB must then be told to look for debug files in the user's profile, by
34252 setting the @code{debug-file-directory} variable (consider setting it
34253 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
34257 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
34260 From there on, GDB will pick up debugging information from the
34261 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
34263 In addition, you will most likely want GDB to be able to show the source
34264 code being debugged. To do that, you will have to unpack the source
34265 code of the package of interest (obtained with @code{guix build
34266 --source}, @pxref{Invoking guix build}), and to point GDB to that source
34267 directory using the @code{directory} command (@pxref{Source Path,
34268 @code{directory},, gdb, Debugging with GDB}).
34270 @c XXX: keep me up-to-date
34271 The @code{debug} output mechanism in Guix is implemented by the
34272 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
34273 opt-in---debugging information is available only for the packages with
34274 definitions explicitly declaring a @code{debug} output. To check
34275 whether a package has a @code{debug} output, use @command{guix package
34276 --list-available} (@pxref{Invoking guix package}).
34278 Read on for how to deal with packages lacking a @code{debug} output.
34280 @node Rebuilding Debug Info
34281 @section Rebuilding Debug Info
34283 @cindex debugging info, rebuilding
34284 As we saw above, some packages, but not all, provide debugging info in a
34285 @code{debug} output. What can you do when debugging info is missing?
34286 The @option{--with-debug-info} option provides a solution to that: it
34287 allows you to rebuild the package(s) for which debugging info is
34288 missing---and only those---and to graft those onto the application
34289 you're debugging. Thus, while it's not as fast as installing a
34290 @code{debug} output, it is relatively inexpensive.
34292 Let's illustrate that. Suppose you're experiencing a bug in Inkscape
34293 and would like to see what's going on in GLib, a library that's deep
34294 down in its dependency graph. As it turns out, GLib does not have a
34295 @code{debug} output and the backtrace GDB shows is all sadness:
34299 #0 0x00007ffff5f92190 in g_getenv ()
34300 from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
34301 #1 0x00007ffff608a7d6 in gobject_init_ctor ()
34302 from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
34303 #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
34304 env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
34305 #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
34309 To address that, you install Inkscape linked against a variant GLib that
34310 contains debug info:
34313 guix install inkscape --with-debug-info=glib
34316 This time, debugging will be a whole lot nicer:
34319 $ gdb --args sh -c 'exec inkscape'
34322 Function "g_getenv" not defined.
34323 Make breakpoint pending on future shared library load? (y or [n]) y
34324 Breakpoint 1 (g_getenv) pending.
34326 Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
34329 #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
34330 #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
34331 #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
34332 #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
34333 env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
34339 Note that there can be packages for which @option{--with-debug-info}
34340 will not have the desired effect. @xref{Package Transformation Options,
34341 @option{--with-debug-info}}, for more information.
34343 @node Security Updates
34344 @chapter Security Updates
34346 @cindex security updates
34347 @cindex security vulnerabilities
34348 Occasionally, important security vulnerabilities are discovered in software
34349 packages and must be patched. Guix developers try hard to keep track of
34350 known vulnerabilities and to apply fixes as soon as possible in the
34351 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
34352 containing only security updates). The @command{guix lint} tool helps
34353 developers find out about vulnerable versions of software packages in the
34358 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
34359 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
34360 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
34364 @xref{Invoking guix lint}, for more information.
34366 Guix follows a functional
34367 package management discipline (@pxref{Introduction}), which implies
34368 that, when a package is changed, @emph{every package that depends on it}
34369 must be rebuilt. This can significantly slow down the deployment of
34370 fixes in core packages such as libc or Bash, since basically the whole
34371 distribution would need to be rebuilt. Using pre-built binaries helps
34372 (@pxref{Substitutes}), but deployment may still take more time than
34376 To address this, Guix implements @dfn{grafts}, a mechanism that allows
34377 for fast deployment of critical updates without the costs associated
34378 with a whole-distribution rebuild. The idea is to rebuild only the
34379 package that needs to be patched, and then to ``graft'' it onto packages
34380 explicitly installed by the user and that were previously referring to
34381 the original package. The cost of grafting is typically very low, and
34382 order of magnitudes lower than a full rebuild of the dependency chain.
34384 @cindex replacements of packages, for grafts
34385 For instance, suppose a security update needs to be applied to Bash.
34386 Guix developers will provide a package definition for the ``fixed''
34387 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
34388 Packages}). Then, the original package definition is augmented with a
34389 @code{replacement} field pointing to the package containing the bug fix:
34396 (replacement bash-fixed)))
34399 From there on, any package depending directly or indirectly on Bash---as
34400 reported by @command{guix gc --requisites} (@pxref{Invoking guix
34401 gc})---that is installed is automatically ``rewritten'' to refer to
34402 @code{bash-fixed} instead of @code{bash}. This grafting process takes
34403 time proportional to the size of the package, usually less than a
34404 minute for an ``average'' package on a recent machine. Grafting is
34405 recursive: when an indirect dependency requires grafting, then grafting
34406 ``propagates'' up to the package that the user is installing.
34408 Currently, the length of the name and version of the graft and that of
34409 the package it replaces (@code{bash-fixed} and @code{bash} in the example
34410 above) must be equal. This restriction mostly comes from the fact that
34411 grafting works by patching files, including binary files, directly.
34412 Other restrictions may apply: for instance, when adding a graft to a
34413 package providing a shared library, the original shared library and its
34414 replacement must have the same @code{SONAME} and be binary-compatible.
34416 The @option{--no-grafts} command-line option allows you to forcefully
34417 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
34421 guix build bash --no-grafts
34425 returns the store file name of the original Bash, whereas:
34432 returns the store file name of the ``fixed'', replacement Bash. This
34433 allows you to distinguish between the two variants of Bash.
34435 To verify which Bash your whole profile refers to, you can run
34436 (@pxref{Invoking guix gc}):
34439 guix gc -R `readlink -f ~/.guix-profile` | grep bash
34443 @dots{} and compare the store file names that you get with those above.
34444 Likewise for a complete Guix system generation:
34447 guix gc -R `guix system build my-config.scm` | grep bash
34450 Lastly, to check which Bash running processes are using, you can use the
34451 @command{lsof} command:
34454 lsof | grep /gnu/store/.*bash
34458 @node Bootstrapping
34459 @chapter Bootstrapping
34461 @c Adapted from the ELS 2013 paper.
34463 @cindex bootstrapping
34465 Bootstrapping in our context refers to how the distribution gets built
34466 ``from nothing''. Remember that the build environment of a derivation
34467 contains nothing but its declared inputs (@pxref{Introduction}). So
34468 there's an obvious chicken-and-egg problem: how does the first package
34469 get built? How does the first compiler get compiled?
34471 It is tempting to think of this question as one that only die-hard
34472 hackers may care about. However, while the answer to that question is
34473 technical in nature, its implications are wide-ranging. How the
34474 distribution is bootstrapped defines the extent to which we, as
34475 individuals and as a collective of users and hackers, can trust the
34476 software we run. It is a central concern from the standpoint of
34477 @emph{security} and from a @emph{user freedom} viewpoint.
34479 @cindex bootstrap binaries
34480 The GNU system is primarily made of C code, with libc at its core. The
34481 GNU build system itself assumes the availability of a Bourne shell and
34482 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
34483 `grep'. Furthermore, build programs---programs that run
34484 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
34485 (@pxref{Derivations}). Consequently, to be able to build anything at
34486 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
34487 Binutils, libc, and the other packages mentioned above---the
34488 @dfn{bootstrap binaries}.
34490 These bootstrap binaries are ``taken for granted'', though we can also
34491 re-create them if needed (@pxref{Preparing to Use the Bootstrap
34495 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
34496 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
34499 @node Reduced Binary Seed Bootstrap
34500 @section The Reduced Binary Seed Bootstrap
34502 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
34503 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
34504 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
34505 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
34506 ``taken for granted.''
34508 Taking the bootstrap binaries for granted means that we consider them to
34509 be a correct and trustworthy ``seed'' for building the complete system.
34510 Therein lies a problem: the combined size of these bootstrap binaries is
34511 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
34512 or even inspecting these is next to impossible.
34514 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
34515 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
34516 Source Bootstrap'' and while we are working towards that goal it would
34517 be hyperbole to use that term for what we do now.}.
34519 The Reduced Binary Seed bootstrap removes the most critical tools---from a
34520 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
34521 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
34522 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
34523 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
34525 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
34526 C Library are built from source. From here on the more traditional
34527 bootstrap process resumes. This approach has reduced the bootstrap
34528 binaries in size to about 145MB in Guix v1.1.
34530 The next step that Guix has taken is to replace the shell and all its
34531 utilities with implementations in Guile Scheme, the @emph{Scheme-only
34532 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
34533 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
34534 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
34535 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
34536 removed are now built from source.
34538 Building the GNU System from source is currently only possible by adding
34539 some historical GNU packages as intermediate steps@footnote{Packages
34540 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
34541 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
34542 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
34543 and GNU packages become more bootstrappable again (e.g., new releases of
34544 GNU Sed will also ship as gzipped tarballs again, as alternative to the
34545 hard to bootstrap @code{xz}-compression), this set of added packages can
34546 hopefully be reduced again.
34548 The graph below shows the resulting dependency graph for
34549 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
34550 traditional bootstrap of the rest of the Guix System.
34552 @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
34553 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
34555 The only significant binary bootstrap seeds that remain@footnote{
34556 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
34557 together with @code{mes}.} are a Scheme intepreter and a Scheme
34558 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
34559 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
34560 to get Guile running.}.
34562 This further reduction has brought down the size of the binary seed to
34563 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
34565 Work is ongoing to remove all binary blobs from our free software
34566 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
34567 is work to bring these bootstraps to the @code{arm-linux} and
34568 @code{aarch64-linux} architectures and to the Hurd.
34570 If you are interested, join us on @samp{#bootstrappable} on the Freenode
34571 IRC network or discuss on @email{bug-mes@@gnu.org} or
34572 @email{gash-devel@@nongnu.org}.
34574 @node Preparing to Use the Bootstrap Binaries
34575 @section Preparing to Use the Bootstrap Binaries
34577 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
34578 @c large image, it's hard to scroll. Oh well.
34579 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
34581 The figure above shows the very beginning of the dependency graph of the
34582 distribution, corresponding to the package definitions of the @code{(gnu
34583 packages bootstrap)} module. A similar figure can be generated with
34584 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
34587 guix graph -t derivation \
34588 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
34589 | dot -Tps > gcc.ps
34592 or, for the further Reduced Binary Seed bootstrap
34595 guix graph -t derivation \
34596 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
34597 | dot -Tps > mes.ps
34600 At this level of detail, things are
34601 slightly complex. First, Guile itself consists of an ELF executable,
34602 along with many source and compiled Scheme files that are dynamically
34603 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
34604 tarball shown in this graph. This tarball is part of Guix's ``source''
34605 distribution, and gets inserted into the store with @code{add-to-store}
34606 (@pxref{The Store}).
34608 But how do we write a derivation that unpacks this tarball and adds it
34609 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
34610 derivation---the first one that gets built---uses @code{bash} as its
34611 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
34612 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
34613 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
34614 the Guix source distribution, whose sole purpose is to allow the Guile
34615 tarball to be unpacked.
34617 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
34618 Guile that can be used to run subsequent build programs. Its first task
34619 is to download tarballs containing the other pre-built binaries---this
34620 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
34621 @code{ftp-client.scm} are used for this purpose. The
34622 @code{module-import.drv} derivations import those modules in a directory
34623 in the store, using the original layout. The
34624 @code{module-import-compiled.drv} derivations compile those modules, and
34625 write them in an output directory with the right layout. This
34626 corresponds to the @code{#:modules} argument of
34627 @code{build-expression->derivation} (@pxref{Derivations}).
34629 Finally, the various tarballs are unpacked by the derivations
34630 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
34631 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
34632 point we have a working C tool chain.
34634 @unnumberedsec Building the Build Tools
34636 Bootstrapping is complete when we have a full tool chain that does not
34637 depend on the pre-built bootstrap tools discussed above. This
34638 no-dependency requirement is verified by checking whether the files of
34639 the final tool chain contain references to the @file{/gnu/store}
34640 directories of the bootstrap inputs. The process that leads to this
34641 ``final'' tool chain is described by the package definitions found in
34642 the @code{(gnu packages commencement)} module.
34644 The @command{guix graph} command allows us to ``zoom out'' compared to
34645 the graph above, by looking at the level of package objects instead of
34646 individual derivations---remember that a package may translate to
34647 several derivations, typically one derivation to download its source,
34648 one to build the Guile modules it needs, and one to actually build the
34649 package from source. The command:
34652 guix graph -t bag \
34653 -e '(@@@@ (gnu packages commencement)
34654 glibc-final-with-bootstrap-bash)' | xdot -
34658 displays the dependency graph leading to the ``final'' C
34659 library@footnote{You may notice the @code{glibc-intermediate} label,
34660 suggesting that it is not @emph{quite} final, but as a good
34661 approximation, we will consider it final.}, depicted below.
34663 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
34665 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
34666 The first tool that gets built with the bootstrap binaries is
34667 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
34668 for all the following packages. From there Findutils and Diffutils get
34671 Then come the first-stage Binutils and GCC, built as pseudo cross
34672 tools---i.e., with @option{--target} equal to @option{--host}. They are
34673 used to build libc. Thanks to this cross-build trick, this libc is
34674 guaranteed not to hold any reference to the initial tool chain.
34676 From there the final Binutils and GCC (not shown above) are built. GCC
34677 uses @command{ld} from the final Binutils, and links programs against
34678 the just-built libc. This tool chain is used to build the other
34679 packages used by Guix and by the GNU Build System: Guile, Bash,
34682 And voilà! At this point we have the complete set of build tools that
34683 the GNU Build System expects. These are in the @code{%final-inputs}
34684 variable of the @code{(gnu packages commencement)} module, and are
34685 implicitly used by any package that uses @code{gnu-build-system}
34686 (@pxref{Build Systems, @code{gnu-build-system}}).
34689 @unnumberedsec Building the Bootstrap Binaries
34691 @cindex bootstrap binaries
34692 Because the final tool chain does not depend on the bootstrap binaries,
34693 those rarely need to be updated. Nevertheless, it is useful to have an
34694 automated way to produce them, should an update occur, and this is what
34695 the @code{(gnu packages make-bootstrap)} module provides.
34697 The following command builds the tarballs containing the bootstrap binaries
34698 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
34699 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
34700 and Guile, and a tarball containing a mixture of Coreutils and other basic
34701 command-line tools):
34704 guix build bootstrap-tarballs
34707 The generated tarballs are those that should be referred to in the
34708 @code{(gnu packages bootstrap)} module mentioned at the beginning of
34711 Still here? Then perhaps by now you've started to wonder: when do we
34712 reach a fixed point? That is an interesting question! The answer is
34713 unknown, but if you would like to investigate further (and have
34714 significant computational and storage resources to do so), then let us
34717 @unnumberedsec Reducing the Set of Bootstrap Binaries
34719 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
34720 binary code! Why is that a problem? It's a problem because these big chunks
34721 of binary code are practically non-auditable, which makes it hard to establish
34722 what source code produced them. Every unauditable binary also leaves us
34723 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
34724 paper @emph{Reflections on Trusting Trust}.
34726 This is mitigated by the fact that our bootstrap binaries were generated
34727 from an earlier Guix revision. Nevertheless it lacks the level of
34728 transparency that we get in the rest of the package dependency graph,
34729 where Guix always gives us a source-to-binary mapping. Thus, our goal
34730 is to reduce the set of bootstrap binaries to the bare minimum.
34732 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
34733 on-going projects to do that. One of these is about replacing the
34734 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
34735 of increasing complexity, which could be built from source starting from
34736 a simple and auditable assembler.
34738 Our first major achievement is the replacement of of GCC, the GNU C Library
34739 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
34740 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
34741 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
34742 bootstrapped yet and thus we inject them as binary seeds. We call this the
34743 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
34744 binaries! Also, it has eliminated the C compiler binary; i686-linux and
34745 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
34747 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
34748 also looking at any other bootstrap binaries. Your help is welcome!
34751 @chapter Porting to a New Platform
34753 As discussed above, the GNU distribution is self-contained, and
34754 self-containment is achieved by relying on pre-built ``bootstrap
34755 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
34756 operating system kernel, CPU architecture, and application binary
34757 interface (ABI). Thus, to port the distribution to a platform that is
34758 not yet supported, one must build those bootstrap binaries, and update
34759 the @code{(gnu packages bootstrap)} module to use them on that platform.
34761 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
34762 When everything goes well, and assuming the GNU tool chain supports the
34763 target platform, this can be as simple as running a command like this
34767 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
34770 For this to work, the @code{glibc-dynamic-linker} procedure in
34771 @code{(gnu packages bootstrap)} must be augmented to return the right
34772 file name for libc's dynamic linker on that platform; likewise,
34773 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
34774 taught about the new platform.
34776 Once these are built, the @code{(gnu packages bootstrap)} module needs
34777 to be updated to refer to these binaries on the target platform. That
34778 is, the hashes and URLs of the bootstrap tarballs for the new platform
34779 must be added alongside those of the currently supported platforms. The
34780 bootstrap Guile tarball is treated specially: it is expected to be
34781 available locally, and @file{gnu/local.mk} has rules to download it for
34782 the supported architectures; a rule for the new platform must be added
34785 In practice, there may be some complications. First, it may be that the
34786 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
34787 above) is not recognized by all the GNU tools. Typically, glibc
34788 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
34789 configure flag (see @code{gcc.scm} for examples of how to handle this).
34790 Second, some of the required packages could fail to build for that
34791 platform. Lastly, the generated binaries could be broken for some
34794 @c *********************************************************************
34795 @include contributing.texi
34797 @c *********************************************************************
34798 @node Acknowledgments
34799 @chapter Acknowledgments
34801 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
34802 which was designed and
34803 implemented by Eelco Dolstra, with contributions from other people (see
34804 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
34805 management, and promoted unprecedented features, such as transactional
34806 package upgrades and rollbacks, per-user profiles, and referentially
34807 transparent build processes. Without this work, Guix would not exist.
34809 The Nix-based software distributions, Nixpkgs and NixOS, have also been
34810 an inspiration for Guix.
34812 GNU@tie{}Guix itself is a collective work with contributions from a
34813 number of people. See the @file{AUTHORS} file in Guix for more
34814 information on these fine people. The @file{THANKS} file lists people
34815 who have helped by reporting bugs, taking care of the infrastructure,
34816 providing artwork and themes, making suggestions, and more---thank you!
34819 @c *********************************************************************
34820 @node GNU Free Documentation License
34821 @appendix GNU Free Documentation License
34822 @cindex license, GNU Free Documentation License
34823 @include fdl-1.3.texi
34825 @c *********************************************************************
34826 @node Concept Index
34827 @unnumbered Concept Index
34830 @node Programming Index
34831 @unnumbered Programming Index
34832 @syncodeindex tp fn
34833 @syncodeindex vr fn
34838 @c Local Variables:
34839 @c ispell-local-dictionary: "american";