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 Leo Famulari@*
32 Copyright @copyright{} 2015, 2016, 2017, 2018, 2019, 2020 Ricardo Wurmus@*
33 Copyright @copyright{} 2016 Ben Woodcroft@*
34 Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
35 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Efraim Flashner@*
36 Copyright @copyright{} 2016 John Darrington@*
37 Copyright @copyright{} 2016, 2017 Nikita Gillmann@*
38 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Jan Nieuwenhuizen@*
39 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Julien Lepiller@*
40 Copyright @copyright{} 2016 Alex ter Weele@*
41 Copyright @copyright{} 2016, 2017, 2018, 2019 Christopher Baines@*
42 Copyright @copyright{} 2017, 2018, 2019 Clément Lassieur@*
43 Copyright @copyright{} 2017, 2018, 2020 Mathieu Othacehe@*
44 Copyright @copyright{} 2017 Federico Beffa@*
45 Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
46 Copyright @copyright{} 2017 Thomas Danckaert@*
47 Copyright @copyright{} 2017 humanitiesNerd@*
48 Copyright @copyright{} 2017 Christopher Allan Webber@*
49 Copyright @copyright{} 2017, 2018, 2019, 2020 Marius Bakke@*
50 Copyright @copyright{} 2017, 2019, 2020 Hartmut Goebel@*
51 Copyright @copyright{} 2017, 2019, 2020 Maxim Cournoyer@*
52 Copyright @copyright{} 2017, 2018, 2019, 2020 Tobias Geerinckx-Rice@*
53 Copyright @copyright{} 2017 George Clemmer@*
54 Copyright @copyright{} 2017 Andy Wingo@*
55 Copyright @copyright{} 2017, 2018, 2019, 2020 Arun Isaac@*
56 Copyright @copyright{} 2017 nee@*
57 Copyright @copyright{} 2018 Rutger Helling@*
58 Copyright @copyright{} 2018, 2021 Oleg Pykhalov@*
59 Copyright @copyright{} 2018 Mike Gerwitz@*
60 Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
61 Copyright @copyright{} 2018, 2019 Gábor Boskovits@*
62 Copyright @copyright{} 2018, 2019, 2020 Florian Pelz@*
63 Copyright @copyright{} 2018 Laura Lazzati@*
64 Copyright @copyright{} 2018 Alex Vong@*
65 Copyright @copyright{} 2019 Josh Holland@*
66 Copyright @copyright{} 2019, 2020 Diego Nicola Barbato@*
67 Copyright @copyright{} 2019 Ivan Petkov@*
68 Copyright @copyright{} 2019 Jakob L. Kreuze@*
69 Copyright @copyright{} 2019 Kyle Andrews@*
70 Copyright @copyright{} 2019 Alex Griffin@*
71 Copyright @copyright{} 2019, 2020 Guillaume Le Vaillant@*
72 Copyright @copyright{} 2020 Leo Prikler@*
73 Copyright @copyright{} 2019, 2020 Simon Tournier@*
74 Copyright @copyright{} 2020 Wiktor Żelazny@*
75 Copyright @copyright{} 2020 Damien Cassou@*
76 Copyright @copyright{} 2020 Jakub Kądziołka@*
77 Copyright @copyright{} 2020 Jack Hill@*
78 Copyright @copyright{} 2020 Naga Malleswari@*
79 Copyright @copyright{} 2020 Brice Waegeneire@*
80 Copyright @copyright{} 2020 R Veera Kumar@*
81 Copyright @copyright{} 2020 Pierre Langlois@*
82 Copyright @copyright{} 2020 pinoaffe@*
83 Copyright @copyright{} 2020 André Batista@*
84 Copyright @copyright{} 2020 Alexandru-Sergiu Marton@*
85 Copyright @copyright{} 2020 raingloom@*
86 Copyright @copyright{} 2020 Daniel Brooks@*
87 Copyright @copyright{} 2020 John Soo@*
88 Copyright @copyright{} 2020 Jonathan Brielmaier@*
90 Permission is granted to copy, distribute and/or modify this document
91 under the terms of the GNU Free Documentation License, Version 1.3 or
92 any later version published by the Free Software Foundation; with no
93 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
94 copy of the license is included in the section entitled ``GNU Free
95 Documentation License''.
98 @dircategory System administration
100 * Guix: (guix). Manage installed software and system configuration.
101 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
102 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
103 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
104 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
105 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
108 @dircategory Software development
110 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
111 * guix build: (guix)Invoking guix build. Building packages.
112 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
116 @title GNU Guix Reference Manual
117 @subtitle Using the GNU Guix Functional Package Manager
118 @author The GNU Guix Developers
121 @vskip 0pt plus 1filll
122 Edition @value{EDITION} @*
130 @c *********************************************************************
134 This document describes GNU Guix version @value{VERSION}, a functional
135 package management tool written for the GNU system.
137 @c TRANSLATORS: You can replace the following paragraph with information on
138 @c how to join your own translation team and how to report issues with the
140 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
141 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
142 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
143 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
144 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
145 would like to translate it in your native language, consider joining the
146 @uref{https://translationproject.org/domain/guix-manual.html, Translation
150 * Introduction:: What is Guix about?
151 * Installation:: Installing Guix.
152 * System Installation:: Installing the whole operating system.
153 * Getting Started:: Your first steps.
154 * Package Management:: Package installation, upgrade, etc.
155 * Channels:: Customizing the package collection.
156 * Development:: Guix-aided software development.
157 * Programming Interface:: Using Guix in Scheme.
158 * Utilities:: Package management commands.
159 * System Configuration:: Configuring the operating system.
160 * Documentation:: Browsing software user manuals.
161 * Installing Debugging Files:: Feeding the debugger.
162 * Security Updates:: Deploying security fixes quickly.
163 * Bootstrapping:: GNU/Linux built from scratch.
164 * Porting:: Targeting another platform or kernel.
165 * Contributing:: Your help needed!
167 * Acknowledgments:: Thanks!
168 * GNU Free Documentation License:: The license of this manual.
169 * Concept Index:: Concepts.
170 * Programming Index:: Data types, functions, and variables.
173 --- The Detailed Node Listing ---
177 * Managing Software the Guix Way:: What's special.
178 * GNU Distribution:: The packages and tools.
182 * Binary Installation:: Getting Guix running in no time!
183 * Requirements:: Software needed to build and run Guix.
184 * Running the Test Suite:: Testing Guix.
185 * Setting Up the Daemon:: Preparing the build daemon's environment.
186 * Invoking guix-daemon:: Running the build daemon.
187 * Application Setup:: Application-specific setup.
188 * Upgrading Guix:: Upgrading Guix and its build daemon.
190 Setting Up the Daemon
192 * Build Environment Setup:: Preparing the isolated build environment.
193 * Daemon Offload Setup:: Offloading builds to remote machines.
194 * SELinux Support:: Using an SELinux policy for the daemon.
198 * Limitations:: What you can expect.
199 * Hardware Considerations:: Supported hardware.
200 * USB Stick and DVD Installation:: Preparing the installation medium.
201 * Preparing for Installation:: Networking, partitioning, etc.
202 * Guided Graphical Installation:: Easy graphical installation.
203 * Manual Installation:: Manual installation for wizards.
204 * After System Installation:: When installation succeeded.
205 * Installing Guix in a VM:: Guix System playground.
206 * Building the Installation Image:: How this comes to be.
210 * Keyboard Layout and Networking and Partitioning:: Initial setup.
211 * Proceeding with the Installation:: Installing.
215 * Features:: How Guix will make your life brighter.
216 * Invoking guix package:: Package installation, removal, etc.
217 * Substitutes:: Downloading pre-built binaries.
218 * Packages with Multiple Outputs:: Single source package, multiple outputs.
219 * Invoking guix gc:: Running the garbage collector.
220 * Invoking guix pull:: Fetching the latest Guix and distribution.
221 * Invoking guix time-machine:: Running an older revision of Guix.
222 * Inferiors:: Interacting with another revision of Guix.
223 * Invoking guix describe:: Display information about your Guix revision.
224 * Invoking guix archive:: Exporting and importing store files.
228 * Official Substitute Server:: One particular source of substitutes.
229 * Substitute Server Authorization:: How to enable or disable substitutes.
230 * Getting Substitutes from Other Servers:: Substitute diversity.
231 * Substitute Authentication:: How Guix verifies substitutes.
232 * Proxy Settings:: How to get substitutes via proxy.
233 * Substitution Failure:: What happens when substitution fails.
234 * On Trusting Binaries:: How can you trust that binary blob?
238 * Specifying Additional Channels:: Extending the package collection.
239 * Using a Custom Guix Channel:: Using a customized Guix.
240 * Replicating Guix:: Running the @emph{exact same} Guix.
241 * Channel Authentication:: How Guix verifies what it fetches.
242 * Creating a Channel:: How to write your custom channel.
243 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
244 * Declaring Channel Dependencies:: How to depend on other channels.
245 * Specifying Channel Authorizations:: Defining channel authors authorizations.
246 * Primary URL:: Distinguishing mirror to original.
247 * Writing Channel News:: Communicating information to channel's users.
251 * Invoking guix environment:: Setting up development environments.
252 * Invoking guix pack:: Creating software bundles.
253 * The GCC toolchain:: Working with languages supported by GCC.
254 * Invoking guix git authenticate:: Authenticating Git repositories.
256 Programming Interface
258 * Package Modules:: Packages from the programmer's viewpoint.
259 * Defining Packages:: Defining new packages.
260 * Defining Package Variants:: Customizing packages.
261 * Build Systems:: Specifying how packages are built.
262 * Build Phases:: Phases of the build process of a package.
263 * Build Utilities:: Helpers for your package definitions and more.
264 * The Store:: Manipulating the package store.
265 * Derivations:: Low-level interface to package derivations.
266 * The Store Monad:: Purely functional interface to the store.
267 * G-Expressions:: Manipulating build expressions.
268 * Invoking guix repl:: Programming Guix in Guile.
272 * package Reference:: The package data type.
273 * origin Reference:: The origin data type.
277 * Invoking guix build:: Building packages from the command line.
278 * Invoking guix edit:: Editing package definitions.
279 * Invoking guix download:: Downloading a file and printing its hash.
280 * Invoking guix hash:: Computing the cryptographic hash of a file.
281 * Invoking guix import:: Importing package definitions.
282 * Invoking guix refresh:: Updating package definitions.
283 * Invoking guix lint:: Finding errors in package definitions.
284 * Invoking guix size:: Profiling disk usage.
285 * Invoking guix graph:: Visualizing the graph of packages.
286 * Invoking guix publish:: Sharing substitutes.
287 * Invoking guix challenge:: Challenging substitute servers.
288 * Invoking guix copy:: Copying to and from a remote store.
289 * Invoking guix container:: Process isolation.
290 * Invoking guix weather:: Assessing substitute availability.
291 * Invoking guix processes:: Listing client processes.
293 Invoking @command{guix build}
295 * Common Build Options:: Build options for most commands.
296 * Package Transformation Options:: Creating variants of packages.
297 * Additional Build Options:: Options specific to 'guix build'.
298 * Debugging Build Failures:: Real life packaging experience.
302 * Using the Configuration System:: Customizing your GNU system.
303 * operating-system Reference:: Detail of operating-system declarations.
304 * File Systems:: Configuring file system mounts.
305 * Mapped Devices:: Block device extra processing.
306 * User Accounts:: Specifying user accounts.
307 * Keyboard Layout:: How the system interprets key strokes.
308 * Locales:: Language and cultural convention settings.
309 * Services:: Specifying system services.
310 * Setuid Programs:: Programs running with root privileges.
311 * X.509 Certificates:: Authenticating HTTPS servers.
312 * Name Service Switch:: Configuring libc's name service switch.
313 * Initial RAM Disk:: Linux-Libre bootstrapping.
314 * Bootloader Configuration:: Configuring the boot loader.
315 * Invoking guix system:: Instantiating a system configuration.
316 * Invoking guix deploy:: Deploying a system configuration to a remote host.
317 * Running Guix in a VM:: How to run Guix System in a virtual machine.
318 * Defining Services:: Adding new service definitions.
322 * Base Services:: Essential system services.
323 * Scheduled Job Execution:: The mcron service.
324 * Log Rotation:: The rottlog service.
325 * Networking Services:: Network setup, SSH daemon, etc.
326 * Unattended Upgrades:: Automated system upgrades.
327 * X Window:: Graphical display.
328 * Printing Services:: Local and remote printer support.
329 * Desktop Services:: D-Bus and desktop services.
330 * Sound Services:: ALSA and Pulseaudio services.
331 * Database Services:: SQL databases, key-value stores, etc.
332 * Mail Services:: IMAP, POP3, SMTP, and all that.
333 * Messaging Services:: Messaging services.
334 * Telephony Services:: Telephony services.
335 * Monitoring Services:: Monitoring services.
336 * Kerberos Services:: Kerberos services.
337 * LDAP Services:: LDAP services.
338 * Web Services:: Web servers.
339 * Certificate Services:: TLS certificates via Let's Encrypt.
340 * DNS Services:: DNS daemons.
341 * VPN Services:: VPN daemons.
342 * Network File System:: NFS related services.
343 * Continuous Integration:: The Cuirass service.
344 * Power Management Services:: Extending battery life.
345 * Audio Services:: The MPD.
346 * Virtualization Services:: Virtualization services.
347 * Version Control Services:: Providing remote access to Git repositories.
348 * Game Services:: Game servers.
349 * PAM Mount Service:: Service to mount volumes when logging in.
350 * Guix Services:: Services relating specifically to Guix.
351 * Linux Services:: Services tied to the Linux kernel.
352 * Hurd Services:: Services specific for a Hurd System.
353 * Miscellaneous Services:: Other services.
357 * Service Composition:: The model for composing services.
358 * Service Types and Services:: Types and services.
359 * Service Reference:: API reference.
360 * Shepherd Services:: A particular type of service.
362 Installing Debugging Files
364 * Separate Debug Info:: Installing 'debug' outputs.
365 * Rebuilding Debug Info:: Building missing debug info.
369 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
370 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
375 @c *********************************************************************
377 @chapter Introduction
380 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
381 using the international phonetic alphabet (IPA).} is a package
382 management tool for and distribution of the GNU system.
383 Guix makes it easy for unprivileged
384 users to install, upgrade, or remove software packages, to roll back to a
385 previous package set, to build packages from source, and generally
386 assists with the creation and maintenance of software environments.
389 @cindex GuixSD, now Guix System
390 @cindex Guix System Distribution, now Guix System
391 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
392 complements the available tools without interference (@pxref{Installation}),
393 or you can use it as a standalone operating system distribution,
394 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
395 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
396 group everything under the ``Guix'' banner since, after all, Guix System is
397 readily available through the @command{guix system} command, even if you're
398 using a different distro underneath!}. @xref{GNU Distribution}.
401 * Managing Software the Guix Way:: What's special.
402 * GNU Distribution:: The packages and tools.
405 @node Managing Software the Guix Way
406 @section Managing Software the Guix Way
408 @cindex user interfaces
409 Guix provides a command-line package management interface
410 (@pxref{Package Management}), tools to help with software development
411 (@pxref{Development}), command-line utilities for more advanced usage
412 (@pxref{Utilities}), as well as Scheme programming interfaces
413 (@pxref{Programming Interface}).
415 Its @dfn{build daemon} is responsible for building packages on behalf of
416 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
417 binaries from authorized sources (@pxref{Substitutes}).
419 @cindex extensibility of the distribution
420 @cindex customization, of packages
421 Guix includes package definitions for many GNU and non-GNU packages, all
422 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
423 user's computing freedom}. It is @emph{extensible}: users can write
424 their own package definitions (@pxref{Defining Packages}) and make them
425 available as independent package modules (@pxref{Package Modules}). It
426 is also @emph{customizable}: users can @emph{derive} specialized package
427 definitions from existing ones, including from the command line
428 (@pxref{Package Transformation Options}).
430 @cindex functional package management
432 Under the hood, Guix implements the @dfn{functional package management}
433 discipline pioneered by Nix (@pxref{Acknowledgments}).
434 In Guix, the package build and installation process is seen
435 as a @emph{function}, in the mathematical sense. That function takes inputs,
436 such as build scripts, a compiler, and libraries, and
437 returns an installed package. As a pure function, its result depends
438 solely on its inputs---for instance, it cannot refer to software or
439 scripts that were not explicitly passed as inputs. A build function
440 always produces the same result when passed a given set of inputs. It
441 cannot alter the environment of the running system in
442 any way; for instance, it cannot create, modify, or delete files outside
443 of its build and installation directories. This is achieved by running
444 build processes in isolated environments (or @dfn{containers}), where only their
445 explicit inputs are visible.
448 The result of package build functions is @dfn{cached} in the file
449 system, in a special directory called @dfn{the store} (@pxref{The
450 Store}). Each package is installed in a directory of its own in the
451 store---by default under @file{/gnu/store}. The directory name contains
452 a hash of all the inputs used to build that package; thus, changing an
453 input yields a different directory name.
455 This approach is the foundation for the salient features of Guix: support
456 for transactional package upgrade and rollback, per-user installation, and
457 garbage collection of packages (@pxref{Features}).
460 @node GNU Distribution
461 @section GNU Distribution
464 Guix comes with a distribution of the GNU system consisting entirely of
465 free software@footnote{The term ``free'' here refers to the
466 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
467 users of that software}.}. The
468 distribution can be installed on its own (@pxref{System Installation}),
469 but it is also possible to install Guix as a package manager on top of
470 an installed GNU/Linux system (@pxref{Installation}). When we need to
471 distinguish between the two, we refer to the standalone distribution as
474 The distribution provides core GNU packages such as GNU libc, GCC, and
475 Binutils, as well as many GNU and non-GNU applications. The complete
476 list of available packages can be browsed
477 @url{https://www.gnu.org/software/guix/packages,on-line} or by
478 running @command{guix package} (@pxref{Invoking guix package}):
481 guix package --list-available
484 Our goal is to provide a practical 100% free software distribution of
485 Linux-based and other variants of GNU, with a focus on the promotion and
486 tight integration of GNU components, and an emphasis on programs and
487 tools that help users exert that freedom.
489 Packages are currently available on the following platforms:
494 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel.
497 Intel 32-bit architecture (IA32), Linux-Libre kernel.
500 ARMv7-A architecture with hard float, Thumb-2 and NEON,
501 using the EABI hard-float application binary interface (ABI),
502 and Linux-Libre kernel.
505 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
508 @uref{https://hurd.gnu.org, GNU/Hurd} on the Intel 32-bit architecture
511 This configuration is experimental and under development. The easiest
512 way for you to give it a try is by setting up an instance of
513 @code{hurd-vm-service-type} on your GNU/Linux machine
514 (@pxref{transparent-emulation-qemu, @code{hurd-vm-service-type}}).
515 @xref{Contributing}, on how to help!
517 @item mips64el-linux (deprecated)
518 little-endian 64-bit MIPS processors, specifically the Loongson series,
519 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
520 supported; in particular, there is no ongoing work to ensure that this
521 architecture still works. Should someone decide they wish to revive this
522 architecture then the code is still available.
526 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
527 configuration and Guix takes care of instantiating the configuration in a
528 transactional, reproducible, and stateless fashion (@pxref{System
529 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
530 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
531 Manual}), the well-known GNU utilities and tool chain, as well as the
532 graphical environment or system services of your choice.
534 Guix System is available on all the above platforms except
535 @code{mips64el-linux}.
538 For information on porting to other architectures or kernels,
541 Building this distribution is a cooperative effort, and you are invited
542 to join! @xref{Contributing}, for information about how you can help.
545 @c *********************************************************************
547 @chapter Installation
549 @cindex installing Guix
552 We recommend the use of this
553 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
554 shell installer script} to install Guix on top of a running GNU/Linux system,
555 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
556 with the installation of the package manager, which can be done on top of a
557 running GNU/Linux system. If, instead, you want to install the complete GNU
558 operating system, @pxref{System Installation}.} The script automates the
559 download, installation, and initial configuration of Guix. It should be run
563 @cindex foreign distro
564 @cindex directories related to foreign distro
565 When installed on a foreign distro, GNU@tie{}Guix complements the available
566 tools without interference. Its data lives exclusively in two directories,
567 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
568 such as @file{/etc}, are left untouched.
570 Once installed, Guix can be updated by running @command{guix pull}
571 (@pxref{Invoking guix pull}).
573 If you prefer to perform the installation steps manually or want to tweak
574 them, you may find the following subsections useful. They describe the
575 software requirements of Guix, as well as how to install it manually and get
579 * Binary Installation:: Getting Guix running in no time!
580 * Requirements:: Software needed to build and run Guix.
581 * Running the Test Suite:: Testing Guix.
582 * Setting Up the Daemon:: Preparing the build daemon's environment.
583 * Invoking guix-daemon:: Running the build daemon.
584 * Application Setup:: Application-specific setup.
585 * Upgrading Guix:: Upgrading Guix and its build daemon.
588 @node Binary Installation
589 @section Binary Installation
591 @cindex installing Guix from binaries
592 @cindex installer script
593 This section describes how to install Guix on an arbitrary system from a
594 self-contained tarball providing binaries for Guix and for all its
595 dependencies. This is often quicker than installing from source, which
596 is described in the next sections. The only requirement is to have
599 @c Note duplicated from the ``Installation'' node.
601 We recommend the use of this
602 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
603 shell installer script}. The script automates the download, installation, and
604 initial configuration steps described below. It should be run as the root
605 user. As root, you can thus run this:
609 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
610 chmod +x guix-install.sh
614 When you're done, @pxref{Application Setup} for extra configuration you
615 might need, and @ref{Getting Started} for your first steps!
618 Installing goes along these lines:
622 @cindex downloading Guix binary
623 Download the binary tarball from
624 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
625 where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
626 @code{i686} (32-bits) machine already running the kernel Linux, and so on
627 (@pxref{GNU Distribution}).
629 @c The following is somewhat duplicated in ``System Installation''.
630 Make sure to download the associated @file{.sig} file and to verify the
631 authenticity of the tarball against it, along these lines:
634 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
635 $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
638 If that command fails because you do not have the required public key,
639 then run this command to import it:
642 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
643 -qO - | gpg --import -
647 and rerun the @code{gpg --verify} command.
649 Take note that a warning like ``This key is not certified with a trusted
650 signature!'' is normal.
652 @c end authentication part
655 Now, you need to become the @code{root} user. Depending on your distribution,
656 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
660 # tar --warning=no-timestamp -xf \
661 /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
662 # mv var/guix /var/ && mv gnu /
665 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
666 The latter contains a ready-to-use profile for @code{root} (see next
669 Do @emph{not} unpack the tarball on a working Guix system since that
670 would overwrite its own essential files.
672 The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
673 not emit warnings about ``implausibly old time stamps'' (such
674 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
676 They stem from the fact that all the
677 files in the archive have their modification time set to 1 (which
678 means January 1st, 1970). This is done on purpose to make sure the
679 archive content is independent of its creation time, thus making it
683 Make the profile available under @file{~root/.config/guix/current}, which is
684 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
687 # mkdir -p ~root/.config/guix
688 # ln -sf /var/guix/profiles/per-user/root/current-guix \
689 ~root/.config/guix/current
692 Source @file{etc/profile} to augment @env{PATH} and other relevant
693 environment variables:
696 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
697 source $GUIX_PROFILE/etc/profile
701 Create the group and user accounts for build users as explained below
702 (@pxref{Build Environment Setup}).
705 Run the daemon, and set it to automatically start on boot.
707 If your host distro uses the systemd init system, this can be achieved
710 @c Versions of systemd that supported symlinked service files are not
711 @c yet widely deployed, so we should suggest that users copy the service
714 @c See this thread for more information:
715 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
718 # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
719 ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
721 # systemctl enable --now gnu-store.mount guix-daemon
724 If your host distro uses the Upstart init system:
727 # initctl reload-configuration
728 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
733 Otherwise, you can still start the daemon manually with:
736 # ~root/.config/guix/current/bin/guix-daemon \
737 --build-users-group=guixbuild
741 Make the @command{guix} command available to other users on the machine,
745 # mkdir -p /usr/local/bin
747 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
750 It is also a good idea to make the Info version of this manual available
754 # mkdir -p /usr/local/share/info
755 # cd /usr/local/share/info
756 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
760 That way, assuming @file{/usr/local/share/info} is in the search path,
761 running @command{info guix} will open this manual (@pxref{Other Info
762 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
766 @cindex substitutes, authorization thereof
767 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
768 (@pxref{Substitutes}), authorize them:
771 # guix archive --authorize < \
772 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
776 Each user may need to perform a few additional steps to make their Guix
777 environment ready for use, @pxref{Application Setup}.
780 Voilà, the installation is complete!
782 You can confirm that Guix is working by installing a sample package into
789 The binary installation tarball can be (re)produced and verified simply
790 by running the following command in the Guix source tree:
793 make guix-binary.@var{system}.tar.xz
797 ...@: which, in turn, runs:
800 guix pack -s @var{system} --localstatedir \
801 --profile-name=current-guix guix
804 @xref{Invoking guix pack}, for more info on this handy tool.
807 @section Requirements
809 This section lists requirements when building Guix from source. The
810 build procedure for Guix is the same as for other GNU software, and is
811 not covered here. Please see the files @file{README} and @file{INSTALL}
812 in the Guix source tree for additional details.
814 @cindex official website
815 GNU Guix is available for download from its website at
816 @url{https://www.gnu.org/software/guix/}.
818 GNU Guix depends on the following packages:
821 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x or
823 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
826 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
827 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
828 Guile,, gnutls-guile, GnuTLS-Guile});
830 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
832 @item @uref{https://notabug.org/guile-zlib/guile-zlib, Guile-zlib};
833 @item @uref{https://notabug.org/guile-lzlib/guile-lzlib, Guile-lzlib};
834 @item @uref{https://www.nongnu.org/guile-avahi/, Guile-Avahi};
836 @c FIXME: Specify a version number once a release has been made.
837 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, version 0.3.0
839 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON}
841 @item @url{https://www.gnu.org/software/make/, GNU Make}.
844 The following dependencies are optional:
848 @c Note: We need at least 0.13.0 for #:nodelay.
849 Support for build offloading (@pxref{Daemon Offload Setup}) and
850 @command{guix copy} (@pxref{Invoking guix copy}) depends on
851 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
852 version 0.13.0 or later.
855 @uref{https://ngyro.com/software/guile-semver.html, Guile-Semver} for
856 the @code{crate} importer (@pxref{Invoking guix import}).
859 When @url{http://www.bzip.org, libbz2} is available,
860 @command{guix-daemon} can use it to compress build logs.
863 Unless @option{--disable-daemon} was passed to @command{configure}, the
864 following packages are also needed:
867 @item @url{https://gnupg.org/, GNU libgcrypt};
868 @item @url{https://sqlite.org, SQLite 3};
869 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
873 @cindex state directory
874 When configuring Guix on a system that already has a Guix installation,
875 be sure to specify the same state directory as the existing installation
876 using the @option{--localstatedir} option of the @command{configure}
877 script (@pxref{Directory Variables, @code{localstatedir},, standards,
878 GNU Coding Standards}). Usually, this @var{localstatedir} option is
879 set to the value @file{/var}. The @command{configure} script protects
880 against unintended misconfiguration of @var{localstatedir} so you do not
881 inadvertently corrupt your store (@pxref{The Store}).
883 @node Running the Test Suite
884 @section Running the Test Suite
887 After a successful @command{configure} and @code{make} run, it is a good
888 idea to run the test suite. It can help catch issues with the setup or
889 environment, or bugs in Guix itself---and really, reporting test
890 failures is a good way to help improve the software. To run the test
897 Test cases can run in parallel: you can use the @code{-j} option of
898 GNU@tie{}make to speed things up. The first run may take a few minutes
899 on a recent machine; subsequent runs will be faster because the store
900 that is created for test purposes will already have various things in
903 It is also possible to run a subset of the tests by defining the
904 @code{TESTS} makefile variable as in this example:
907 make check TESTS="tests/store.scm tests/cpio.scm"
910 By default, tests results are displayed at a file level. In order to
911 see the details of every individual test cases, it is possible to define
912 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
915 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
918 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
919 @file{test-suite.log} file. Please specify the Guix version being used
920 as well as version numbers of the dependencies (@pxref{Requirements}) in
923 Guix also comes with a whole-system test suite that tests complete
924 Guix System instances. It can only run on systems where
925 Guix is already installed, using:
932 or, again, by defining @code{TESTS} to select a subset of tests to run:
935 make check-system TESTS="basic mcron"
938 These system tests are defined in the @code{(gnu tests @dots{})}
939 modules. They work by running the operating systems under test with
940 lightweight instrumentation in a virtual machine (VM). They can be
941 computationally intensive or rather cheap, depending on whether
942 substitutes are available for their dependencies (@pxref{Substitutes}).
943 Some of them require a lot of storage space to hold VM images.
945 Again in case of test failures, please send @email{bug-guix@@gnu.org}
948 @node Setting Up the Daemon
949 @section Setting Up the Daemon
952 Operations such as building a package or running the garbage collector
953 are all performed by a specialized process, the @dfn{build daemon}, on
954 behalf of clients. Only the daemon may access the store and its
955 associated database. Thus, any operation that manipulates the store
956 goes through the daemon. For instance, command-line tools such as
957 @command{guix package} and @command{guix build} communicate with the
958 daemon (@i{via} remote procedure calls) to instruct it what to do.
960 The following sections explain how to prepare the build daemon's
961 environment. See also @ref{Substitutes}, for information on how to allow
962 the daemon to download pre-built binaries.
965 * Build Environment Setup:: Preparing the isolated build environment.
966 * Daemon Offload Setup:: Offloading builds to remote machines.
967 * SELinux Support:: Using an SELinux policy for the daemon.
970 @node Build Environment Setup
971 @subsection Build Environment Setup
973 @cindex build environment
974 In a standard multi-user setup, Guix and its daemon---the
975 @command{guix-daemon} program---are installed by the system
976 administrator; @file{/gnu/store} is owned by @code{root} and
977 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
978 Guix tools to build packages or otherwise access the store, and the
979 daemon will do it on their behalf, ensuring that the store is kept in a
980 consistent state, and allowing built packages to be shared among users.
983 When @command{guix-daemon} runs as @code{root}, you may not want package
984 build processes themselves to run as @code{root} too, for obvious
985 security reasons. To avoid that, a special pool of @dfn{build users}
986 should be created for use by build processes started by the daemon.
987 These build users need not have a shell and a home directory: they will
988 just be used when the daemon drops @code{root} privileges in build
989 processes. Having several such users allows the daemon to launch
990 distinct build processes under separate UIDs, which guarantees that they
991 do not interfere with each other---an essential feature since builds are
992 regarded as pure functions (@pxref{Introduction}).
994 On a GNU/Linux system, a build user pool may be created like this (using
995 Bash syntax and the @code{shadow} commands):
997 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
998 @c for why `-G' is needed.
1000 # groupadd --system guixbuild
1001 # for i in `seq -w 1 10`;
1003 useradd -g guixbuild -G guixbuild \
1004 -d /var/empty -s `which nologin` \
1005 -c "Guix build user $i" --system \
1011 The number of build users determines how many build jobs may run in
1012 parallel, as specified by the @option{--max-jobs} option
1013 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
1014 @command{guix system vm} and related commands, you may need to add the
1015 build users to the @code{kvm} group so they can access @file{/dev/kvm},
1016 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
1017 (@pxref{Invoking guix system}).
1019 The @code{guix-daemon} program may then be run as @code{root} with the
1020 following command@footnote{If your machine uses the systemd init system,
1021 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
1022 file in @file{/etc/systemd/system} will ensure that
1023 @command{guix-daemon} is automatically started. Similarly, if your
1024 machine uses the Upstart init system, drop the
1025 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
1026 file in @file{/etc/init}.}:
1029 # guix-daemon --build-users-group=guixbuild
1034 This way, the daemon starts build processes in a chroot, under one of
1035 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
1036 environment contains nothing but:
1038 @c Keep this list in sync with libstore/build.cc! -----------------------
1041 a minimal @code{/dev} directory, created mostly independently from the
1042 host @code{/dev}@footnote{``Mostly'', because while the set of files
1043 that appear in the chroot's @code{/dev} is fixed, most of these files
1044 can only be created if the host has them.};
1047 the @code{/proc} directory; it only shows the processes of the container
1048 since a separate PID name space is used;
1051 @file{/etc/passwd} with an entry for the current user and an entry for
1055 @file{/etc/group} with an entry for the user's group;
1058 @file{/etc/hosts} with an entry that maps @code{localhost} to
1062 a writable @file{/tmp} directory.
1065 You can influence the directory where the daemon stores build trees
1066 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1067 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1068 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1069 This way, the value of @env{TMPDIR} does not leak inside build
1070 environments, which avoids discrepancies in cases where build processes
1071 capture the name of their build tree.
1075 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1076 environment variables for HTTP and HTTPS downloads it performs, be it
1077 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1078 (@pxref{Substitutes}).
1080 If you are installing Guix as an unprivileged user, it is still possible
1081 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1082 However, build processes will not be isolated from one another, and not
1083 from the rest of the system. Thus, build processes may interfere with
1084 each other, and may access programs, libraries, and other files
1085 available on the system---making it much harder to view them as
1086 @emph{pure} functions.
1089 @node Daemon Offload Setup
1090 @subsection Using the Offload Facility
1094 When desired, the build daemon can @dfn{offload} derivation builds to
1095 other machines running Guix, using the @code{offload} @dfn{build
1096 hook}@footnote{This feature is available only when
1097 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1098 present.}. When that feature is enabled, a list of user-specified build
1099 machines is read from @file{/etc/guix/machines.scm}; every time a build
1100 is requested, for instance via @code{guix build}, the daemon attempts to
1101 offload it to one of the machines that satisfy the constraints of the
1102 derivation, in particular its system types---e.g., @code{x86_64-linux}.
1103 A single machine can have multiple system types, either because its
1104 architecture natively supports it, via emulation
1105 (@pxref{transparent-emulation-qemu, Transparent Emulation with QEMU}),
1106 or both. Missing prerequisites for the build are
1107 copied over SSH to the target machine, which then proceeds with the
1108 build; upon success the output(s) of the build are copied back to the
1109 initial machine. The offload facility comes with a basic scheduler that
1110 attempts to select the best machine. The best machine is chosen among
1111 the available machines based on criteria such as:
1115 The availability of a build slot. A build machine can have as many
1116 build slots (connections) as the value of the @code{parallel-builds}
1117 field of its @code{build-machine} object.
1120 Its relative speed, as defined via the @code{speed} field of its
1121 @code{build-machine} object.
1124 Its load. The normalized machine load must be lower than a threshold
1125 value, configurable via the @code{overload-threshold} field of its
1126 @code{build-machine} object.
1129 Disk space availability. More than a 100 MiB must be available.
1132 The @file{/etc/guix/machines.scm} file typically looks like this:
1135 (list (build-machine
1136 (name "eightysix.example.org")
1137 (systems (list "x86_64-linux" "i686-linux"))
1138 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1140 (speed 2.)) ;incredibly fast!
1143 (name "armeight.example.org")
1144 (systems (list "aarch64-linux"))
1145 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1148 (string-append (getenv "HOME")
1149 "/.ssh/identity-for-guix"))))
1153 In the example above we specify a list of two build machines, one for
1154 the @code{x86_64} and @code{i686} architectures and one for the
1155 @code{aarch64} architecture.
1157 In fact, this file is---not surprisingly!---a Scheme file that is
1158 evaluated when the @code{offload} hook is started. Its return value
1159 must be a list of @code{build-machine} objects. While this example
1160 shows a fixed list of build machines, one could imagine, say, using
1161 DNS-SD to return a list of potential build machines discovered in the
1162 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1163 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1166 @deftp {Data Type} build-machine
1167 This data type represents build machines to which the daemon may offload
1168 builds. The important fields are:
1173 The host name of the remote machine.
1176 The system types the remote machine supports---e.g., @code{(list
1177 "x86_64-linux" "i686-linux")}.
1180 The user account to use when connecting to the remote machine over SSH.
1181 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1182 allow non-interactive logins.
1185 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1186 This is used to authenticate the machine when we connect to it. It is a
1187 long string that looks like this:
1190 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1193 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1194 key can be found in a file such as
1195 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1197 If the machine is running the SSH daemon of GNU@tie{}lsh,
1198 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1199 similar file. It can be converted to the OpenSSH format using
1200 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1203 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1204 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1209 A number of optional fields may be specified:
1213 @item @code{port} (default: @code{22})
1214 Port number of SSH server on the machine.
1216 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1217 The SSH private key file to use when connecting to the machine, in
1218 OpenSSH format. This key must not be protected with a passphrase.
1220 Note that the default value is the private key @emph{of the root
1221 account}. Make sure it exists if you use the default.
1223 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1224 @itemx @code{compression-level} (default: @code{3})
1225 The SSH-level compression methods and compression level requested.
1227 Note that offloading relies on SSH compression to reduce bandwidth usage
1228 when transferring files to and from build machines.
1230 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1231 File name of the Unix-domain socket @command{guix-daemon} is listening
1234 @item @code{overload-threshold} (default: @code{0.6})
1235 The load threshold above which a potential offload machine is
1236 disregarded by the offload scheduler. The value roughly translates to
1237 the total processor usage of the build machine, ranging from 0.0 (0%) to
1238 1.0 (100%). It can also be disabled by setting
1239 @code{overload-threshold} to @code{#f}.
1241 @item @code{parallel-builds} (default: @code{1})
1242 The number of builds that may run in parallel on the machine.
1244 @item @code{speed} (default: @code{1.0})
1245 A ``relative speed factor''. The offload scheduler will tend to prefer
1246 machines with a higher speed factor.
1248 @item @code{features} (default: @code{'()})
1249 A list of strings denoting specific features supported by the machine.
1250 An example is @code{"kvm"} for machines that have the KVM Linux modules
1251 and corresponding hardware support. Derivations can request features by
1252 name, and they will be scheduled on matching build machines.
1257 The @command{guix} command must be in the search path on the build
1258 machines. You can check whether this is the case by running:
1261 ssh build-machine guix repl --version
1264 There is one last thing to do once @file{machines.scm} is in place. As
1265 explained above, when offloading, files are transferred back and forth
1266 between the machine stores. For this to work, you first need to
1267 generate a key pair on each machine to allow the daemon to export signed
1268 archives of files from the store (@pxref{Invoking guix archive}):
1271 # guix archive --generate-key
1275 Each build machine must authorize the key of the master machine so that
1276 it accepts store items it receives from the master:
1279 # guix archive --authorize < master-public-key.txt
1283 Likewise, the master machine must authorize the key of each build machine.
1285 All the fuss with keys is here to express pairwise mutual trust
1286 relations between the master and the build machines. Concretely, when
1287 the master receives files from a build machine (and @i{vice versa}), its
1288 build daemon can make sure they are genuine, have not been tampered
1289 with, and that they are signed by an authorized key.
1291 @cindex offload test
1292 To test whether your setup is operational, run this command on the
1299 This will attempt to connect to each of the build machines specified in
1300 @file{/etc/guix/machines.scm}, make sure Guix is
1301 available on each machine, attempt to export to the machine and import
1302 from it, and report any error in the process.
1304 If you want to test a different machine file, just specify it on the
1308 # guix offload test machines-qualif.scm
1311 Last, you can test the subset of the machines whose name matches a
1312 regular expression like this:
1315 # guix offload test machines.scm '\.gnu\.org$'
1318 @cindex offload status
1319 To display the current load of all build hosts, run this command on the
1323 # guix offload status
1327 @node SELinux Support
1328 @subsection SELinux Support
1330 @cindex SELinux, daemon policy
1331 @cindex mandatory access control, SELinux
1332 @cindex security, guix-daemon
1333 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1334 can be installed on a system where SELinux is enabled, in order to label
1335 Guix files and to specify the expected behavior of the daemon. Since
1336 Guix System does not provide an SELinux base policy, the daemon policy cannot
1337 be used on Guix System.
1339 @subsubsection Installing the SELinux policy
1340 @cindex SELinux, policy installation
1341 To install the policy run this command as root:
1344 semodule -i etc/guix-daemon.cil
1347 Then relabel the file system with @code{restorecon} or by a different
1348 mechanism provided by your system.
1350 Once the policy is installed, the file system has been relabeled, and
1351 the daemon has been restarted, it should be running in the
1352 @code{guix_daemon_t} context. You can confirm this with the following
1356 ps -Zax | grep guix-daemon
1359 Monitor the SELinux log files as you run a command like @code{guix build
1360 hello} to convince yourself that SELinux permits all necessary
1363 @subsubsection Limitations
1364 @cindex SELinux, limitations
1366 This policy is not perfect. Here is a list of limitations or quirks
1367 that should be considered when deploying the provided SELinux policy for
1372 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1373 operations involve contexts that have anything to do with
1374 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1375 but it would be preferrable to define socket rules for only this label.
1378 @code{guix gc} cannot access arbitrary links to profiles. By design,
1379 the file label of the destination of a symlink is independent of the
1380 file label of the link itself. Although all profiles under
1381 $localstatedir are labelled, the links to these profiles inherit the
1382 label of the directory they are in. For links in the user’s home
1383 directory this will be @code{user_home_t}. But for links from the root
1384 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1385 directory, etc, this won’t work. @code{guix gc} would be prevented from
1386 reading and following these links.
1389 The daemon’s feature to listen for TCP connections might no longer work.
1390 This might require extra rules, because SELinux treats network sockets
1391 differently from files.
1394 Currently all files with a name matching the regular expression
1395 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1396 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1397 that name in any profile would be permitted to run in the
1398 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1399 build a package that provides this executable and convince a user to
1400 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1401 At that point SELinux could not prevent it from accessing files that are
1402 allowed for processes in that domain.
1404 You will need to relabel the store directory after all upgrades to
1405 @file{guix-daemon}, such as after running @code{guix pull}. Assuming the
1406 store is in @file{/gnu}, you can do this with @code{restorecon -vR /gnu},
1407 or by other means provided by your operating system.
1409 We could generate a much more restrictive policy at installation time,
1410 so that only the @emph{exact} file name of the currently installed
1411 @code{guix-daemon} executable would be labelled with
1412 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1413 The downside is that root would have to install or upgrade the policy at
1414 installation time whenever the Guix package that provides the
1415 effectively running @code{guix-daemon} executable is upgraded.
1418 @node Invoking guix-daemon
1419 @section Invoking @command{guix-daemon}
1421 The @command{guix-daemon} program implements all the functionality to
1422 access the store. This includes launching build processes, running the
1423 garbage collector, querying the availability of a build result, etc. It
1424 is normally run as @code{root} like this:
1427 # guix-daemon --build-users-group=guixbuild
1431 For details on how to set it up, @pxref{Setting Up the Daemon}.
1434 @cindex container, build environment
1435 @cindex build environment
1436 @cindex reproducible builds
1437 By default, @command{guix-daemon} launches build processes under
1438 different UIDs, taken from the build group specified with
1439 @option{--build-users-group}. In addition, each build process is run in a
1440 chroot environment that only contains the subset of the store that the
1441 build process depends on, as specified by its derivation
1442 (@pxref{Programming Interface, derivation}), plus a set of specific
1443 system directories. By default, the latter contains @file{/dev} and
1444 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1445 @dfn{container}: in addition to having its own file system tree, it has
1446 a separate mount name space, its own PID name space, network name space,
1447 etc. This helps achieve reproducible builds (@pxref{Features}).
1449 When the daemon performs a build on behalf of the user, it creates a
1450 build directory under @file{/tmp} or under the directory specified by
1451 its @env{TMPDIR} environment variable. This directory is shared with
1452 the container for the duration of the build, though within the container,
1453 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1455 The build directory is automatically deleted upon completion, unless the
1456 build failed and the client specified @option{--keep-failed}
1457 (@pxref{Invoking guix build, @option{--keep-failed}}).
1459 The daemon listens for connections and spawns one sub-process for each session
1460 started by a client (one of the @command{guix} sub-commands). The
1461 @command{guix processes} command allows you to get an overview of the activity
1462 on your system by viewing each of the active sessions and clients.
1463 @xref{Invoking guix processes}, for more information.
1465 The following command-line options are supported:
1468 @item --build-users-group=@var{group}
1469 Take users from @var{group} to run build processes (@pxref{Setting Up
1470 the Daemon, build users}).
1472 @item --no-substitutes
1474 Do not use substitutes for build products. That is, always build things
1475 locally instead of allowing downloads of pre-built binaries
1476 (@pxref{Substitutes}).
1478 When the daemon runs with @option{--no-substitutes}, clients can still
1479 explicitly enable substitution @i{via} the @code{set-build-options}
1480 remote procedure call (@pxref{The Store}).
1482 @anchor{daemon-substitute-urls}
1483 @item --substitute-urls=@var{urls}
1484 Consider @var{urls} the default whitespace-separated list of substitute
1485 source URLs. When this option is omitted,
1486 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1488 This means that substitutes may be downloaded from @var{urls}, as long
1489 as they are signed by a trusted signature (@pxref{Substitutes}).
1491 @xref{Getting Substitutes from Other Servers}, for more information on
1492 how to configure the daemon to get substitutes from other servers.
1496 Do not use offload builds to other machines (@pxref{Daemon Offload
1497 Setup}). That is, always build things locally instead of offloading
1498 builds to remote machines.
1500 @item --cache-failures
1501 Cache build failures. By default, only successful builds are cached.
1503 When this option is used, @command{guix gc --list-failures} can be used
1504 to query the set of store items marked as failed; @command{guix gc
1505 --clear-failures} removes store items from the set of cached failures.
1506 @xref{Invoking guix gc}.
1508 @item --cores=@var{n}
1510 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1513 The default value is @code{0}, but it may be overridden by clients, such
1514 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1517 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1518 in the build process, which can then use it to exploit internal
1519 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1521 @item --max-jobs=@var{n}
1523 Allow at most @var{n} build jobs in parallel. The default value is
1524 @code{1}. Setting it to @code{0} means that no builds will be performed
1525 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1526 Setup}), or simply fail.
1528 @item --max-silent-time=@var{seconds}
1529 When the build or substitution process remains silent for more than
1530 @var{seconds}, terminate it and report a build failure.
1532 The default value is @code{0}, which disables the timeout.
1534 The value specified here can be overridden by clients (@pxref{Common
1535 Build Options, @option{--max-silent-time}}).
1537 @item --timeout=@var{seconds}
1538 Likewise, when the build or substitution process lasts for more than
1539 @var{seconds}, terminate it and report a build failure.
1541 The default value is @code{0}, which disables the timeout.
1543 The value specified here can be overridden by clients (@pxref{Common
1544 Build Options, @option{--timeout}}).
1546 @item --rounds=@var{N}
1547 Build each derivation @var{n} times in a row, and raise an error if
1548 consecutive build results are not bit-for-bit identical. Note that this
1549 setting can be overridden by clients such as @command{guix build}
1550 (@pxref{Invoking guix build}).
1552 When used in conjunction with @option{--keep-failed}, the differing
1553 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1554 This makes it easy to look for differences between the two results.
1557 Produce debugging output.
1559 This is useful to debug daemon start-up issues, but then it may be
1560 overridden by clients, for example the @option{--verbosity} option of
1561 @command{guix build} (@pxref{Invoking guix build}).
1563 @item --chroot-directory=@var{dir}
1564 Add @var{dir} to the build chroot.
1566 Doing this may change the result of build processes---for instance if
1567 they use optional dependencies found in @var{dir} when it is available,
1568 and not otherwise. For that reason, it is not recommended to do so.
1569 Instead, make sure that each derivation declares all the inputs that it
1572 @item --disable-chroot
1573 Disable chroot builds.
1575 Using this option is not recommended since, again, it would allow build
1576 processes to gain access to undeclared dependencies. It is necessary,
1577 though, when @command{guix-daemon} is running under an unprivileged user
1580 @item --log-compression=@var{type}
1581 Compress build logs according to @var{type}, one of @code{gzip},
1582 @code{bzip2}, or @code{none}.
1584 Unless @option{--lose-logs} is used, all the build logs are kept in the
1585 @var{localstatedir}. To save space, the daemon automatically compresses
1586 them with Bzip2 by default.
1588 @item --discover[=yes|no]
1589 Whether to discover substitute servers on the local network using mDNS
1592 This feature is still experimental. However, here are a few
1597 It might be faster/less expensive than fetching from remote servers;
1599 There are no security risks, only genuine substitutes will be used
1600 (@pxref{Substitute Authentication});
1602 An attacker advertising @command{guix publish} on your LAN cannot serve
1603 you malicious binaries, but they can learn what software you’re
1606 Servers may serve substitute over HTTP, unencrypted, so anyone on the
1607 LAN can see what software you’re installing.
1610 It is also possible to enable or disable substitute server discovery at
1611 run-time by running:
1614 herd discover guix-daemon on
1615 herd discover guix-daemon off
1618 @item --disable-deduplication
1619 @cindex deduplication
1620 Disable automatic file ``deduplication'' in the store.
1622 By default, files added to the store are automatically ``deduplicated'':
1623 if a newly added file is identical to another one found in the store,
1624 the daemon makes the new file a hard link to the other file. This can
1625 noticeably reduce disk usage, at the expense of slightly increased
1626 input/output load at the end of a build process. This option disables
1629 @item --gc-keep-outputs[=yes|no]
1630 Tell whether the garbage collector (GC) must keep outputs of live
1634 @cindex garbage collector roots
1635 When set to @code{yes}, the GC will keep the outputs of any live
1636 derivation available in the store---the @file{.drv} files. The default
1637 is @code{no}, meaning that derivation outputs are kept only if they are
1638 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1641 @item --gc-keep-derivations[=yes|no]
1642 Tell whether the garbage collector (GC) must keep derivations
1643 corresponding to live outputs.
1645 When set to @code{yes}, as is the case by default, the GC keeps
1646 derivations---i.e., @file{.drv} files---as long as at least one of their
1647 outputs is live. This allows users to keep track of the origins of
1648 items in their store. Setting it to @code{no} saves a bit of disk
1651 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1652 liveness to flow from outputs to derivations, and setting
1653 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1654 derivations to outputs. When both are set to @code{yes}, the effect is
1655 to keep all the build prerequisites (the sources, compiler, libraries,
1656 and other build-time tools) of live objects in the store, regardless of
1657 whether these prerequisites are reachable from a GC root. This is
1658 convenient for developers since it saves rebuilds or downloads.
1660 @item --impersonate-linux-2.6
1661 On Linux-based systems, impersonate Linux 2.6. This means that the
1662 kernel's @command{uname} system call will report 2.6 as the release number.
1664 This might be helpful to build programs that (usually wrongfully) depend
1665 on the kernel version number.
1668 Do not keep build logs. By default they are kept under
1669 @file{@var{localstatedir}/guix/log}.
1671 @item --system=@var{system}
1672 Assume @var{system} as the current system type. By default it is the
1673 architecture/kernel pair found at configure time, such as
1674 @code{x86_64-linux}.
1676 @item --listen=@var{endpoint}
1677 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1678 as the file name of a Unix-domain socket if it starts with
1679 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1680 host name or host name and port to listen to. Here are a few examples:
1683 @item --listen=/gnu/var/daemon
1684 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1685 creating it if needed.
1687 @item --listen=localhost
1688 @cindex daemon, remote access
1689 @cindex remote access to the daemon
1690 @cindex daemon, cluster setup
1691 @cindex clusters, daemon setup
1692 Listen for TCP connections on the network interface corresponding to
1693 @code{localhost}, on port 44146.
1695 @item --listen=128.0.0.42:1234
1696 Listen for TCP connections on the network interface corresponding to
1697 @code{128.0.0.42}, on port 1234.
1700 This option can be repeated multiple times, in which case
1701 @command{guix-daemon} accepts connections on all the specified
1702 endpoints. Users can tell client commands what endpoint to connect to
1703 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1704 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1707 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1708 @option{--listen=@var{host}} is suitable on local networks, such as
1709 clusters, where only trusted nodes may connect to the build daemon. In
1710 other cases where remote access to the daemon is needed, we recommend
1711 using Unix-domain sockets along with SSH.
1714 When @option{--listen} is omitted, @command{guix-daemon} listens for
1715 connections on the Unix-domain socket located at
1716 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1720 @node Application Setup
1721 @section Application Setup
1723 @cindex foreign distro
1724 When using Guix on top of GNU/Linux distribution other than Guix System---a
1725 so-called @dfn{foreign distro}---a few additional steps are needed to
1726 get everything in place. Here are some of them.
1730 @anchor{locales-and-locpath}
1731 @cindex locales, when not on Guix System
1733 @vindex GUIX_LOCPATH
1734 Packages installed @i{via} Guix will not use the locale data of the
1735 host system. Instead, you must first install one of the locale packages
1736 available with Guix and then define the @env{GUIX_LOCPATH} environment
1740 $ guix install glibc-locales
1741 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1744 Note that the @code{glibc-locales} package contains data for all the
1745 locales supported by the GNU@tie{}libc and weighs in at around
1746 917@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1747 limited to a few UTF-8 locales.
1749 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1750 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1751 Manual}). There are two important differences though:
1755 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1756 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1757 to make sure the programs of the foreign distro will not end up loading
1758 incompatible locale data.
1761 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1762 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1763 should your Guix profile contain a mixture of programs linked against
1764 different libc version, each libc version will only try to load locale
1765 data in the right format.
1768 This is important because the locale data format used by different libc
1769 versions may be incompatible.
1771 @subsection Name Service Switch
1773 @cindex name service switch, glibc
1774 @cindex NSS (name service switch), glibc
1775 @cindex nscd (name service caching daemon)
1776 @cindex name service caching daemon (nscd)
1777 When using Guix on a foreign distro, we @emph{strongly recommend} that
1778 the system run the GNU C library's @dfn{name service cache daemon},
1779 @command{nscd}, which should be listening on the
1780 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1781 installed with Guix may fail to look up host names or user accounts, or
1782 may even crash. The next paragraphs explain why.
1784 @cindex @file{nsswitch.conf}
1785 The GNU C library implements a @dfn{name service switch} (NSS), which is
1786 an extensible mechanism for ``name lookups'' in general: host name
1787 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1788 The GNU C Library Reference Manual}).
1790 @cindex Network information service (NIS)
1791 @cindex NIS (Network information service)
1792 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1793 lookup implementations: for example, the @code{nss-mdns} plugin allow
1794 resolution of @code{.local} host names, the @code{nis} plugin allows
1795 user account lookup using the Network information service (NIS), and so
1796 on. These extra ``lookup services'' are configured system-wide in
1797 @file{/etc/nsswitch.conf}, and all the programs running on the system
1798 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1801 When they perform a name lookup---for instance by calling the
1802 @code{getaddrinfo} function in C---applications first try to connect to
1803 the nscd; on success, nscd performs name lookups on their behalf. If
1804 the nscd is not running, then they perform the name lookup by
1805 themselves, by loading the name lookup services into their own address
1806 space and running it. These name lookup services---the
1807 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1808 the host system's C library, rather than from the C library the
1809 application is linked against (the C library coming from Guix).
1811 And this is where the problem is: if your application is linked against
1812 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1813 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1814 likely crash or have its name lookups fail unexpectedly.
1816 Running @command{nscd} on the system, among other advantages, eliminates
1817 this binary incompatibility problem because those @code{libnss_*.so}
1818 files are loaded in the @command{nscd} process, not in applications
1821 @subsection X11 Fonts
1824 The majority of graphical applications use Fontconfig to locate and
1825 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1826 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1827 by default. Thus, to allow graphical applications installed with Guix
1828 to display fonts, you have to install fonts with Guix as well.
1829 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1830 @code{font-gnu-freefont}.
1832 @cindex @code{fc-cache}
1834 Once you have installed or removed fonts, or when you notice an
1835 application that does not find fonts, you may need to install Fontconfig
1836 and to force an update of its font cache by running:
1839 guix install fontconfig
1843 To display text written in Chinese languages, Japanese, or Korean in
1844 graphical applications, consider installing
1845 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1846 has multiple outputs, one per language family (@pxref{Packages with
1847 Multiple Outputs}). For instance, the following command installs fonts
1848 for Chinese languages:
1851 guix install font-adobe-source-han-sans:cn
1854 @cindex @code{xterm}
1855 Older programs such as @command{xterm} do not use Fontconfig and instead
1856 rely on server-side font rendering. Such programs require to specify a
1857 full name of a font using XLFD (X Logical Font Description), like this:
1860 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1863 To be able to use such full names for the TrueType fonts installed in
1864 your Guix profile, you need to extend the font path of the X server:
1866 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1867 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1869 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1872 @cindex @code{xlsfonts}
1873 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1874 to make sure your TrueType fonts are listed there.
1877 @subsection X.509 Certificates
1879 @cindex @code{nss-certs}
1880 The @code{nss-certs} package provides X.509 certificates, which allow
1881 programs to authenticate Web servers accessed over HTTPS.
1883 When using Guix on a foreign distro, you can install this package and
1884 define the relevant environment variables so that packages know where to
1885 look for certificates. @xref{X.509 Certificates}, for detailed
1888 @subsection Emacs Packages
1890 @cindex @code{emacs}
1891 When you install Emacs packages with Guix, the Elisp files are placed
1892 under the @file{share/emacs/site-lisp/} directory of the profile in
1893 which they are installed. The Elisp libraries are made available to
1894 Emacs through the @env{EMACSLOADPATH} environment variable, which is
1895 set when installing Emacs itself.
1897 Additionally, autoload definitions are automatically evaluated at the
1898 initialization of Emacs, by the Guix-specific
1899 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
1900 want to avoid auto-loading the Emacs packages installed with Guix, you
1901 can do so by running Emacs with the @option{--no-site-file} option
1902 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1905 @node Upgrading Guix
1906 @section Upgrading Guix
1908 @cindex Upgrading Guix, on a foreign distro
1910 To upgrade Guix, run:
1916 @xref{Invoking guix pull}, for more information.
1918 @cindex upgrading Guix for the root user, on a foreign distro
1919 @cindex upgrading the Guix daemon, on a foreign distro
1920 @cindex @command{guix pull} for the root user, on a foreign distro
1922 On a foreign distro, you can upgrade the build daemon by running:
1929 followed by (assuming your distro uses the systemd service management
1933 systemctl restart guix-daemon.service
1936 On Guix System, upgrading the daemon is achieved by reconfiguring the
1937 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
1941 @c *********************************************************************
1942 @node System Installation
1943 @chapter System Installation
1945 @cindex installing Guix System
1946 @cindex Guix System, installation
1947 This section explains how to install Guix System
1948 on a machine. Guix, as a package manager, can
1949 also be installed on top of a running GNU/Linux system,
1950 @pxref{Installation}.
1954 @c This paragraph is for people reading this from tty2 of the
1955 @c installation image.
1956 You are reading this documentation with an Info reader. For details on
1957 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1958 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1959 Info}. Hit @kbd{l} afterwards to come back here.
1961 Alternatively, run @command{info info} in another tty to keep the manual
1967 * Limitations:: What you can expect.
1968 * Hardware Considerations:: Supported hardware.
1969 * USB Stick and DVD Installation:: Preparing the installation medium.
1970 * Preparing for Installation:: Networking, partitioning, etc.
1971 * Guided Graphical Installation:: Easy graphical installation.
1972 * Manual Installation:: Manual installation for wizards.
1973 * After System Installation:: When installation succeeded.
1974 * Installing Guix in a VM:: Guix System playground.
1975 * Building the Installation Image:: How this comes to be.
1979 @section Limitations
1981 We consider Guix System to be ready for a wide range of ``desktop'' and server
1982 use cases. The reliability guarantees it provides---transactional upgrades
1983 and rollbacks, reproducibility---make it a solid foundation.
1985 Nevertheless, before you proceed with the installation, be aware of the
1986 following noteworthy limitations applicable to version @value{VERSION}:
1990 More and more system services are provided (@pxref{Services}), but some
1994 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1995 as well as a number of X11 window managers. However, KDE is currently
1999 More than a disclaimer, this is an invitation to report issues (and success
2000 stories!), and to join us in improving it. @xref{Contributing}, for more
2004 @node Hardware Considerations
2005 @section Hardware Considerations
2007 @cindex hardware support on Guix System
2008 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
2009 builds around the kernel Linux-libre, which means that only hardware for
2010 which free software drivers and firmware exist is supported. Nowadays,
2011 a wide range of off-the-shelf hardware is supported on
2012 GNU/Linux-libre---from keyboards to graphics cards to scanners and
2013 Ethernet controllers. Unfortunately, there are still areas where
2014 hardware vendors deny users control over their own computing, and such
2015 hardware is not supported on Guix System.
2017 @cindex WiFi, hardware support
2018 One of the main areas where free drivers or firmware are lacking is WiFi
2019 devices. WiFi devices known to work include those using Atheros chips
2020 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
2021 driver, and those using Broadcom/AirForce chips (BCM43xx with
2022 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
2023 Linux-libre driver. Free firmware exists for both and is available
2024 out-of-the-box on Guix System, as part of @code{%base-firmware}
2025 (@pxref{operating-system Reference, @code{firmware}}).
2027 @cindex RYF, Respects Your Freedom
2028 The @uref{https://www.fsf.org/, Free Software Foundation} runs
2029 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
2030 certification program for hardware products that respect your freedom
2031 and your privacy and ensure that you have control over your device. We
2032 encourage you to check the list of RYF-certified devices.
2034 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
2035 web site. It contains a catalog of hardware devices with information
2036 about their support in GNU/Linux.
2039 @node USB Stick and DVD Installation
2040 @section USB Stick and DVD Installation
2042 An ISO-9660 installation image that can be written to a USB stick or
2043 burnt to a DVD can be downloaded from
2044 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz},
2045 where you can replace @code{x86_64-linux} with one of:
2049 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
2052 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
2055 @c start duplication of authentication part from ``Binary Installation''
2056 Make sure to download the associated @file{.sig} file and to verify the
2057 authenticity of the image against it, along these lines:
2060 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
2061 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
2064 If that command fails because you do not have the required public key,
2065 then run this command to import it:
2068 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
2069 -qO - | gpg --import -
2073 and rerun the @code{gpg --verify} command.
2075 Take note that a warning like ``This key is not certified with a trusted
2076 signature!'' is normal.
2080 This image contains the tools necessary for an installation.
2081 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
2083 @unnumberedsubsec Copying to a USB Stick
2085 To copy the image to a USB stick, follow these steps:
2089 Decompress the image using the @command{xz} command:
2092 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
2096 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
2097 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
2098 copy the image with:
2101 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX status=progress
2105 Access to @file{/dev/sdX} usually requires root privileges.
2108 @unnumberedsubsec Burning on a DVD
2110 To copy the image to a DVD, follow these steps:
2114 Decompress the image using the @command{xz} command:
2117 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
2121 Insert a blank DVD into your machine, and determine
2122 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
2123 copy the image with:
2126 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
2129 Access to @file{/dev/srX} usually requires root privileges.
2132 @unnumberedsubsec Booting
2134 Once this is done, you should be able to reboot the system and boot from
2135 the USB stick or DVD. The latter usually requires you to get in the
2136 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2137 In order to boot from Libreboot, switch to the command mode by pressing
2138 the @kbd{c} key and type @command{search_grub usb}.
2140 @xref{Installing Guix in a VM}, if, instead, you would like to install
2141 Guix System in a virtual machine (VM).
2144 @node Preparing for Installation
2145 @section Preparing for Installation
2147 Once you have booted, you can use the guided graphical installer, which makes
2148 it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
2149 if you are already familiar with GNU/Linux and if you want more control than
2150 what the graphical installer provides, you can choose the ``manual''
2151 installation process (@pxref{Manual Installation}).
2153 The graphical installer is available on TTY1. You can obtain root shells on
2154 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2155 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2156 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2157 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2158 which allows you to select text with the left mouse button and to paste it
2159 with the middle button.
2162 Installation requires access to the Internet so that any missing
2163 dependencies of your system configuration can be downloaded. See the
2164 ``Networking'' section below.
2167 @node Guided Graphical Installation
2168 @section Guided Graphical Installation
2170 The graphical installer is a text-based user interface. It will guide you,
2171 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2173 The first dialog boxes allow you to set up the system as you use it during the
2174 installation: you can choose the language, keyboard layout, and set up
2175 networking, which will be used during the installation. The image below shows
2176 the networking dialog.
2178 @image{images/installer-network,5in,, networking setup with the graphical installer}
2180 Later steps allow you to partition your hard disk, as shown in the image
2181 below, to choose whether or not to use encrypted file systems, to enter the
2182 host name and root password, and to create an additional account, among other
2185 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2187 Note that, at any time, the installer allows you to exit the current
2188 installation step and resume at a previous step, as show in the image below.
2190 @image{images/installer-resume,5in,, resuming the installation process}
2192 Once you're done, the installer produces an operating system configuration and
2193 displays it (@pxref{Using the Configuration System}). At that point you can
2194 hit ``OK'' and installation will proceed. On success, you can reboot into the
2195 new system and enjoy. @xref{After System Installation}, for what's next!
2198 @node Manual Installation
2199 @section Manual Installation
2201 This section describes how you would ``manually'' install GNU@tie{}Guix System
2202 on your machine. This option requires familiarity with GNU/Linux, with the
2203 shell, and with common administration tools. If you think this is not for
2204 you, consider using the guided graphical installer (@pxref{Guided Graphical
2207 The installation system provides root shells on TTYs 3 to 6; press
2208 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2209 many common tools needed to install the system. But it is also a full-blown
2210 Guix System, which means that you can install additional packages, should you
2211 need it, using @command{guix package} (@pxref{Invoking guix package}).
2214 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2215 * Proceeding with the Installation:: Installing.
2218 @node Keyboard Layout and Networking and Partitioning
2219 @subsection Keyboard Layout, Networking, and Partitioning
2221 Before you can install the system, you may want to adjust the keyboard layout,
2222 set up networking, and partition your target hard disk. This section will
2223 guide you through this.
2225 @subsubsection Keyboard Layout
2227 @cindex keyboard layout
2228 The installation image uses the US qwerty keyboard layout. If you want
2229 to change it, you can use the @command{loadkeys} command. For example,
2230 the following command selects the Dvorak keyboard layout:
2236 See the files under @file{/run/current-system/profile/share/keymaps} for
2237 a list of available keyboard layouts. Run @command{man loadkeys} for
2240 @subsubsection Networking
2242 Run the following command to see what your network interfaces are called:
2249 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2255 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2256 Wired interfaces have a name starting with @samp{e}; for example, the
2257 interface corresponding to the first on-board Ethernet controller is
2258 called @samp{eno1}. Wireless interfaces have a name starting with
2259 @samp{w}, like @samp{w1p2s0}.
2262 @item Wired connection
2263 To configure a wired network run the following command, substituting
2264 @var{interface} with the name of the wired interface you want to use.
2267 ifconfig @var{interface} up
2271 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2274 ip link set @var{interface} up
2277 @item Wireless connection
2280 To configure wireless networking, you can create a configuration file
2281 for the @command{wpa_supplicant} configuration tool (its location is not
2282 important) using one of the available text editors such as
2286 nano wpa_supplicant.conf
2289 As an example, the following stanza can go to this file and will work
2290 for many wireless networks, provided you give the actual SSID and
2291 passphrase for the network you are connecting to:
2295 ssid="@var{my-ssid}"
2297 psk="the network's secret passphrase"
2301 Start the wireless service and run it in the background with the
2302 following command (substitute @var{interface} with the name of the
2303 network interface you want to use):
2306 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2309 Run @command{man wpa_supplicant} for more information.
2313 At this point, you need to acquire an IP address. On a network where IP
2314 addresses are automatically assigned @i{via} DHCP, you can run:
2317 dhclient -v @var{interface}
2320 Try to ping a server to see if networking is up and running:
2326 Setting up network access is almost always a requirement because the
2327 image does not contain all the software and tools that may be needed.
2329 @cindex proxy, during system installation
2330 If you need HTTP and HTTPS access to go through a proxy, run the
2334 herd set-http-proxy guix-daemon @var{URL}
2338 where @var{URL} is the proxy URL, for example
2339 @code{http://example.org:8118}.
2341 @cindex installing over SSH
2342 If you want to, you can continue the installation remotely by starting
2346 herd start ssh-daemon
2349 Make sure to either set a password with @command{passwd}, or configure
2350 OpenSSH public key authentication before logging in.
2352 @subsubsection Disk Partitioning
2354 Unless this has already been done, the next step is to partition, and
2355 then format the target partition(s).
2357 The installation image includes several partitioning tools, including
2358 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2359 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2360 the partition layout you want:
2366 If your disk uses the GUID Partition Table (GPT) format and you plan to
2367 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2368 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2371 @cindex EFI, installation
2372 @cindex UEFI, installation
2373 @cindex ESP, EFI system partition
2374 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2375 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2376 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2379 parted /dev/sda set 1 esp on
2383 @vindex grub-bootloader
2384 @vindex grub-efi-bootloader
2385 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2386 @file{/sys/firmware/efi} exists in the installation image, then you should
2387 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2388 Otherwise you should use the BIOS-based GRUB, known as
2389 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2393 Once you are done partitioning the target hard disk drive, you have to
2394 create a file system on the relevant partition(s)@footnote{Currently
2395 Guix System only supports ext4, btrfs, JFS, and F2FS file systems. In
2396 particular, code that reads file system UUIDs and labels only works for these
2397 file system types.}. For the ESP, if you have one and assuming it is
2398 @file{/dev/sda1}, run:
2401 mkfs.fat -F32 /dev/sda1
2404 For the root file system, ext4 is the most widely used format. Other
2405 file systems, such as Btrfs, support compression, which is reported to
2406 nicely complement file deduplication that the daemon performs
2407 independently of the file system (@pxref{Invoking guix-daemon,
2410 Preferably, assign file systems a label so that you can easily and
2411 reliably refer to them in @code{file-system} declarations (@pxref{File
2412 Systems}). This is typically done using the @code{-L} option of
2413 @command{mkfs.ext4} and related commands. So, assuming the target root
2414 partition lives at @file{/dev/sda2}, a file system with the label
2415 @code{my-root} can be created with:
2418 mkfs.ext4 -L my-root /dev/sda2
2421 @cindex encrypted disk
2422 If you are instead planning to encrypt the root partition, you can use
2423 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2424 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2425 @code{man cryptsetup}} for more information). Assuming you want to
2426 store the root partition on @file{/dev/sda2}, the command sequence would
2427 be along these lines:
2430 cryptsetup luksFormat /dev/sda2
2431 cryptsetup open --type luks /dev/sda2 my-partition
2432 mkfs.ext4 -L my-root /dev/mapper/my-partition
2435 Once that is done, mount the target file system under @file{/mnt}
2436 with a command like (again, assuming @code{my-root} is the label of the
2440 mount LABEL=my-root /mnt
2443 Also mount any other file systems you would like to use on the target
2444 system relative to this path. If you have opted for @file{/boot/efi} as an
2445 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2446 found by @code{guix system init} afterwards.
2448 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2449 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2450 sure to initialize them with @command{mkswap}. Assuming you have one
2451 swap partition on @file{/dev/sda3}, you would run:
2458 Alternatively, you may use a swap file. For example, assuming that in
2459 the new system you want to use the file @file{/swapfile} as a swap file,
2460 you would run@footnote{This example will work for many types of file
2461 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2462 btrfs), the required steps may be different. For details, see the
2463 manual pages for @command{mkswap} and @command{swapon}.}:
2466 # This is 10 GiB of swap space. Adjust "count" to change the size.
2467 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2468 # For security, make the file readable and writable only by root.
2469 chmod 600 /mnt/swapfile
2470 mkswap /mnt/swapfile
2471 swapon /mnt/swapfile
2474 Note that if you have encrypted the root partition and created a swap
2475 file in its file system as described above, then the encryption also
2476 protects the swap file, just like any other file in that file system.
2478 @node Proceeding with the Installation
2479 @subsection Proceeding with the Installation
2481 With the target partitions ready and the target root mounted on
2482 @file{/mnt}, we're ready to go. First, run:
2485 herd start cow-store /mnt
2488 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2489 during the installation phase are written to the target disk on @file{/mnt}
2490 rather than kept in memory. This is necessary because the first phase of
2491 the @command{guix system init} command (see below) entails downloads or
2492 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2494 Next, you have to edit a file and
2495 provide the declaration of the operating system to be installed. To
2496 that end, the installation system comes with three text editors. We
2497 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2498 supports syntax highlighting and parentheses matching; other editors
2499 include GNU Zile (an Emacs clone), and
2500 nvi (a clone of the original BSD @command{vi} editor).
2501 We strongly recommend storing that file on the target root file system, say,
2502 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2503 configuration file once you have rebooted into the newly-installed system.
2505 @xref{Using the Configuration System}, for an overview of the
2506 configuration file. The example configurations discussed in that
2507 section are available under @file{/etc/configuration} in the
2508 installation image. Thus, to get started with a system configuration
2509 providing a graphical display server (a ``desktop'' system), you can run
2510 something along these lines:
2514 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2515 # nano /mnt/etc/config.scm
2518 You should pay attention to what your configuration file contains, and
2523 Make sure the @code{bootloader-configuration} form refers to the target
2524 you want to install GRUB on. It should mention @code{grub-bootloader} if
2525 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2526 for newer UEFI systems. For legacy systems, the @code{target} field
2527 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2528 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2529 currently mounted and a @code{file-system} entry is specified in your
2533 Be sure that your file system labels match the value of their respective
2534 @code{device} fields in your @code{file-system} configuration, assuming
2535 your @code{file-system} configuration uses the @code{file-system-label}
2536 procedure in its @code{device} field.
2539 If there are encrypted or RAID partitions, make sure to add a
2540 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2543 Once you are done preparing the configuration file, the new system must
2544 be initialized (remember that the target root file system is mounted
2548 guix system init /mnt/etc/config.scm /mnt
2552 This copies all the necessary files and installs GRUB on
2553 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2554 more information, @pxref{Invoking guix system}. This command may trigger
2555 downloads or builds of missing packages, which can take some time.
2557 Once that command has completed---and hopefully succeeded!---you can run
2558 @command{reboot} and boot into the new system. The @code{root} password
2559 in the new system is initially empty; other users' passwords need to be
2560 initialized by running the @command{passwd} command as @code{root},
2561 unless your configuration specifies otherwise
2562 (@pxref{user-account-password, user account passwords}).
2563 @xref{After System Installation}, for what's next!
2566 @node After System Installation
2567 @section After System Installation
2569 Success, you've now booted into Guix System! From then on, you can update the
2570 system whenever you want by running, say:
2574 sudo guix system reconfigure /etc/config.scm
2578 This builds a new system generation with the latest packages and services
2579 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2580 your system includes the latest security updates (@pxref{Security Updates}).
2582 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2584 @cindex sudo vs. @command{guix pull}
2585 Note that @command{sudo guix} runs your user's @command{guix} command and
2586 @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
2587 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2589 The difference matters here, because @command{guix pull} updates
2590 the @command{guix} command and package definitions only for the user it is ran
2591 as. This means that if you choose to use @command{guix system reconfigure} in
2592 root's login shell, you'll need to @command{guix pull} separately.
2595 Now, @pxref{Getting Started}, and
2596 join us on @code{#guix} on the Freenode IRC network or on
2597 @email{guix-devel@@gnu.org} to share your experience!
2600 @node Installing Guix in a VM
2601 @section Installing Guix in a Virtual Machine
2603 @cindex virtual machine, Guix System installation
2604 @cindex virtual private server (VPS)
2605 @cindex VPS (virtual private server)
2606 If you'd like to install Guix System in a virtual machine (VM) or on a
2607 virtual private server (VPS) rather than on your beloved machine, this
2610 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2611 disk image, follow these steps:
2615 First, retrieve and decompress the Guix system installation image as
2616 described previously (@pxref{USB Stick and DVD Installation}).
2619 Create a disk image that will hold the installed system. To make a
2620 qcow2-formatted disk image, use the @command{qemu-img} command:
2623 qemu-img create -f qcow2 guix-system.img 50G
2626 The resulting file will be much smaller than 50 GB (typically less than
2627 1 MB), but it will grow as the virtualized storage device is filled up.
2630 Boot the USB installation image in an VM:
2633 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2634 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2635 -drive file=guix-system.img \
2636 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2639 @code{-enable-kvm} is optional, but significantly improves performance,
2640 @pxref{Running Guix in a VM}.
2643 You're now root in the VM, proceed with the installation process.
2644 @xref{Preparing for Installation}, and follow the instructions.
2647 Once installation is complete, you can boot the system that's on your
2648 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2651 @node Building the Installation Image
2652 @section Building the Installation Image
2654 @cindex installation image
2655 The installation image described above was built using the @command{guix
2656 system} command, specifically:
2659 guix system disk-image -t iso9660 gnu/system/install.scm
2662 Have a look at @file{gnu/system/install.scm} in the source tree,
2663 and see also @ref{Invoking guix system} for more information
2664 about the installation image.
2666 @section Building the Installation Image for ARM Boards
2668 Many ARM boards require a specific variant of the
2669 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2671 If you build a disk image and the bootloader is not available otherwise
2672 (on another boot drive etc), it's advisable to build an image that
2673 includes the bootloader, specifically:
2676 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2679 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2680 board, a list of possible boards will be printed.
2682 @c *********************************************************************
2683 @node Getting Started
2684 @chapter Getting Started
2686 Presumably, you've reached this section because either you have
2687 installed Guix on top of another distribution (@pxref{Installation}), or
2688 you've installed the standalone Guix System (@pxref{System
2689 Installation}). It's time for you to get started using Guix and this
2690 section aims to help you do that and give you a feel of what it's like.
2692 Guix is about installing software, so probably the first thing you'll
2693 want to do is to actually look for software. Let's say you're looking
2694 for a text editor, you can run:
2697 guix search text editor
2700 This command shows you a number of matching @dfn{packages}, each time
2701 showing the package's name, version, a description, and additional info.
2702 Once you've found out the one you want to use, let's say Emacs (ah ha!),
2703 you can go ahead and install it (run this command as a regular user,
2704 @emph{no need for root privileges}!):
2710 You've installed your first package, congrats! In the process, you've
2711 probably noticed that Guix downloaded pre-built binaries; or, if you
2712 explicitly chose to @emph{not} use pre-built binaries, then probably
2713 Guix is still building software (@pxref{Substitutes}, for more info).
2715 Unless you're using Guix System, the @command{guix install} command must
2716 have printed this hint:
2719 hint: Consider setting the necessary environment variables by running:
2721 GUIX_PROFILE="$HOME/.guix-profile"
2722 . "$GUIX_PROFILE/etc/profile"
2724 Alternately, see `guix package --search-paths -p "$HOME/.guix-profile"'.
2727 Indeed, you must now tell your shell where @command{emacs} and other
2728 programs installed with Guix are to be found. Pasting the two lines
2729 above will do just that: it will add
2730 @code{$HOME/.guix-profile/bin}---which is where the installed package
2731 is---to the @code{PATH} environment variable. You can paste these two
2732 lines in your shell so they take effect right away, but more importantly
2733 you should add them to @file{~/.bash_profile} (or equivalent file if you
2734 do not use Bash) so that environment variables are set next time you
2735 spawn a shell. You only need to do this once and other search paths
2736 environment variables will be taken care of similarly---e.g., if you
2737 eventually install @code{python} and Python libraries, @code{PYTHONPATH}
2740 You can go on installing packages at your will. To list installed
2744 guix package --list-installed
2747 To remove a package, you would unsurprisingly run @command{guix remove}.
2748 A distinguishing feature is the ability to @dfn{roll back} any operation
2749 you made---installation, removal, upgrade---by simply typing:
2752 guix package --roll-back
2755 This is because each operation is in fact a @dfn{transaction} that
2756 creates a new @dfn{generation}. These generations and the difference
2757 between them can be displayed by running:
2760 guix package --list-generations
2763 Now you know the basics of package management!
2765 @quotation Going further
2766 @xref{Package Management}, for more about package management. You may
2767 like @dfn{declarative} package management with @command{guix package
2768 --manifest}, managing separate @dfn{profiles} with @option{--profile},
2769 deleting old generations, collecting garbage, and other nifty features
2770 that will come in handy as you become more familiar with Guix. If you
2771 are a developer, @pxref{Development} for additional tools. And if
2772 you're curious, @pxref{Features}, to peek under the hood.
2775 Once you've installed a set of packages, you will want to periodically
2776 @emph{upgrade} them to the latest and greatest version. To do that, you
2777 will first pull the latest revision of Guix and its package collection:
2783 The end result is a new @command{guix} command, under
2784 @file{~/.config/guix/current/bin}. Unless you're on Guix System, the
2785 first time you run @command{guix pull}, be sure to follow the hint that
2786 the command prints and, similar to what we saw above, paste these two
2787 lines in your terminal and @file{.bash_profile}:
2790 GUIX_PROFILE="$HOME/.config/guix/current"
2791 . "$GUIX_PROFILE/etc/profile"
2795 You must also instruct your shell to point to this new @command{guix}:
2801 At this point, you're running a brand new Guix. You can thus go ahead
2802 and actually upgrade all the packages you previously installed:
2808 As you run this command, you will see that binaries are downloaded (or
2809 perhaps some packages are built), and eventually you end up with the
2810 upgraded packages. Should one of these upgraded packages not be to your
2811 liking, remember you can always roll back!
2813 You can display the exact revision of Guix you're currently using by
2820 The information it displays is @emph{all it takes to reproduce the exact
2821 same Guix}, be it at a different point in time or on a different
2824 @quotation Going further
2825 @xref{Invoking guix pull}, for more information. @xref{Channels}, on
2826 how to specify additional @dfn{channels} to pull packages from, how to
2827 replicate Guix, and more. You may also find @command{time-machine}
2828 handy (@pxref{Invoking guix time-machine}).
2831 If you installed Guix System, one of the first things you'll want to do
2832 is to upgrade your system. Once you've run @command{guix pull} to get
2833 the latest Guix, you can upgrade the system like this:
2836 sudo guix system reconfigure /etc/config.scm
2839 Upon completion, the system runs the latest versions of its software
2840 packages. When you eventually reboot, you'll notice a sub-menu in the
2841 bootloader that reads ``Old system generations'': it's what allows you
2842 to boot @emph{an older generation of your system}, should the latest
2843 generation be ``broken'' or otherwise unsatisfying. Just like for
2844 packages, you can always @emph{roll back} to a previous generation
2845 @emph{of the whole system}:
2848 sudo guix system roll-back
2851 There are many things you'll probably want to tweak on your system:
2852 adding new user accounts, adding new system services, fiddling with the
2853 configuration of those services, etc. The system configuration is
2854 @emph{entirely} described in the @file{/etc/config.scm} file.
2855 @xref{Using the Configuration System}, to learn how to change it.
2857 Now you know enough to get started!
2859 @quotation Resources
2860 The rest of this manual provides a reference for all things Guix. Here
2861 are some additional resources you may find useful:
2865 @xref{Top,,, guix-cookbook, The GNU Guix Cookbook}, for a list of
2866 ``how-to'' style of recipes for a variety of applications.
2869 The @uref{https://guix.gnu.org/guix-refcard.pdf, GNU Guix Reference
2870 Card} lists in two pages most of the commands and options you'll ever
2874 The web site contains @uref{https://guix.gnu.org/en/videos/,
2875 instructional videos} covering topics such as everyday use of Guix, how
2876 to get help, and how to become a contributor.
2879 @xref{Documentation}, to learn how to access documentation on your
2883 We hope you will enjoy Guix as much as the community enjoys building it!
2886 @c *********************************************************************
2887 @node Package Management
2888 @chapter Package Management
2891 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2892 remove software packages, without having to know about their build
2893 procedures or dependencies. Guix also goes beyond this obvious set of
2896 This chapter describes the main features of Guix, as well as the
2897 package management tools it provides. Along with the command-line
2898 interface described below (@pxref{Invoking guix package, @code{guix
2899 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2900 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2901 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2905 guix install emacs-guix
2909 * Features:: How Guix will make your life brighter.
2910 * Invoking guix package:: Package installation, removal, etc.
2911 * Substitutes:: Downloading pre-built binaries.
2912 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2913 * Invoking guix gc:: Running the garbage collector.
2914 * Invoking guix pull:: Fetching the latest Guix and distribution.
2915 * Invoking guix time-machine:: Running an older revision of Guix.
2916 * Inferiors:: Interacting with another revision of Guix.
2917 * Invoking guix describe:: Display information about your Guix revision.
2918 * Invoking guix archive:: Exporting and importing store files.
2924 Here we assume you've already made your first steps with Guix
2925 (@pxref{Getting Started}) and would like to get an overview about what's
2926 going on under the hood.
2928 When using Guix, each package ends up in the @dfn{package store}, in its
2929 own directory---something that resembles
2930 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2932 Instead of referring to these directories, users have their own
2933 @dfn{profile}, which points to the packages that they actually want to
2934 use. These profiles are stored within each user's home directory, at
2935 @code{$HOME/.guix-profile}.
2937 For example, @code{alice} installs GCC 4.7.2. As a result,
2938 @file{/home/alice/.guix-profile/bin/gcc} points to
2939 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2940 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2941 simply continues to point to
2942 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2943 coexist on the same system without any interference.
2945 The @command{guix package} command is the central tool to manage
2946 packages (@pxref{Invoking guix package}). It operates on the per-user
2947 profiles, and can be used @emph{with normal user privileges}.
2949 @cindex transactions
2950 The command provides the obvious install, remove, and upgrade
2951 operations. Each invocation is actually a @emph{transaction}: either
2952 the specified operation succeeds, or nothing happens. Thus, if the
2953 @command{guix package} process is terminated during the transaction,
2954 or if a power outage occurs during the transaction, then the user's
2955 profile remains in its previous state, and remains usable.
2957 In addition, any package transaction may be @emph{rolled back}. So, if,
2958 for example, an upgrade installs a new version of a package that turns
2959 out to have a serious bug, users may roll back to the previous instance
2960 of their profile, which was known to work well. Similarly, the global
2961 system configuration on Guix is subject to
2962 transactional upgrades and roll-back
2963 (@pxref{Using the Configuration System}).
2965 All packages in the package store may be @emph{garbage-collected}.
2966 Guix can determine which packages are still referenced by user
2967 profiles, and remove those that are provably no longer referenced
2968 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2969 generations of their profile so that the packages they refer to can be
2972 @cindex reproducibility
2973 @cindex reproducible builds
2974 Guix takes a @dfn{purely functional} approach to package
2975 management, as described in the introduction (@pxref{Introduction}).
2976 Each @file{/gnu/store} package directory name contains a hash of all the
2977 inputs that were used to build that package---compiler, libraries, build
2978 scripts, etc. This direct correspondence allows users to make sure a
2979 given package installation matches the current state of their
2980 distribution. It also helps maximize @dfn{build reproducibility}:
2981 thanks to the isolated build environments that are used, a given build
2982 is likely to yield bit-identical files when performed on different
2983 machines (@pxref{Invoking guix-daemon, container}).
2986 This foundation allows Guix to support @dfn{transparent binary/source
2987 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2988 available from an external source---a @dfn{substitute}, Guix just
2989 downloads it and unpacks it;
2990 otherwise, it builds the package from source, locally
2991 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2992 reproducible, users do not have to trust servers that provide
2993 substitutes: they can force a local build and @emph{challenge} providers
2994 (@pxref{Invoking guix challenge}).
2996 Control over the build environment is a feature that is also useful for
2997 developers. The @command{guix environment} command allows developers of
2998 a package to quickly set up the right development environment for their
2999 package, without having to manually install the dependencies of the
3000 package into their profile (@pxref{Invoking guix environment}).
3002 @cindex replication, of software environments
3003 @cindex provenance tracking, of software artifacts
3004 All of Guix and its package definitions is version-controlled, and
3005 @command{guix pull} allows you to ``travel in time'' on the history of Guix
3006 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
3007 Guix instance on a different machine or at a later point in time, which in
3008 turn allows you to @emph{replicate complete software environments}, while
3009 retaining precise @dfn{provenance tracking} of the software.
3011 @node Invoking guix package
3012 @section Invoking @command{guix package}
3014 @cindex installing packages
3015 @cindex removing packages
3016 @cindex package installation
3017 @cindex package removal
3018 The @command{guix package} command is the tool that allows users to
3019 install, upgrade, and remove packages, as well as rolling back to
3020 previous configurations. It operates only on the user's own profile,
3021 and works with normal user privileges (@pxref{Features}). Its syntax
3025 guix package @var{options}
3028 @cindex transactions
3029 Primarily, @var{options} specifies the operations to be performed during
3030 the transaction. Upon completion, a new profile is created, but
3031 previous @dfn{generations} of the profile remain available, should the user
3034 For example, to remove @code{lua} and install @code{guile} and
3035 @code{guile-cairo} in a single transaction:
3038 guix package -r lua -i guile guile-cairo
3041 @cindex aliases, for @command{guix package}
3042 For your convenience, we also provide the following aliases:
3046 @command{guix search} is an alias for @command{guix package -s},
3048 @command{guix install} is an alias for @command{guix package -i},
3050 @command{guix remove} is an alias for @command{guix package -r},
3052 @command{guix upgrade} is an alias for @command{guix package -u},
3054 and @command{guix show} is an alias for @command{guix package --show=}.
3057 These aliases are less expressive than @command{guix package} and provide
3058 fewer options, so in some cases you'll probably want to use @command{guix
3061 @command{guix package} also supports a @dfn{declarative approach}
3062 whereby the user specifies the exact set of packages to be available and
3063 passes it @i{via} the @option{--manifest} option
3064 (@pxref{profile-manifest, @option{--manifest}}).
3067 For each user, a symlink to the user's default profile is automatically
3068 created in @file{$HOME/.guix-profile}. This symlink always points to the
3069 current generation of the user's default profile. Thus, users can add
3070 @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
3071 variable, and so on.
3072 @cindex search paths
3073 If you are not using Guix System, consider adding the
3074 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
3075 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
3076 shells get all the right environment variable definitions:
3079 GUIX_PROFILE="$HOME/.guix-profile" ; \
3080 source "$HOME/.guix-profile/etc/profile"
3083 In a multi-user setup, user profiles are stored in a place registered as
3084 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
3085 to (@pxref{Invoking guix gc}). That directory is normally
3086 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
3087 @var{localstatedir} is the value passed to @code{configure} as
3088 @option{--localstatedir}, and @var{user} is the user name. The
3089 @file{per-user} directory is created when @command{guix-daemon} is
3090 started, and the @var{user} sub-directory is created by @command{guix
3093 The @var{options} can be among the following:
3097 @item --install=@var{package} @dots{}
3098 @itemx -i @var{package} @dots{}
3099 Install the specified @var{package}s.
3101 Each @var{package} may specify either a simple package name, such as
3102 @code{guile}, or a package name followed by an at-sign and version number,
3103 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
3104 case, the newest version prefixed by @code{1.8} is selected).
3106 If no version number is specified, the
3107 newest available version will be selected. In addition, @var{package}
3108 may contain a colon, followed by the name of one of the outputs of the
3109 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
3110 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
3111 name (and optionally version) are searched for among the GNU
3112 distribution modules (@pxref{Package Modules}).
3114 @cindex propagated inputs
3115 Sometimes packages have @dfn{propagated inputs}: these are dependencies
3116 that automatically get installed along with the required package
3117 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
3118 @code{package} objects}, for information about propagated inputs in
3119 package definitions).
3121 @anchor{package-cmd-propagated-inputs}
3122 An example is the GNU MPC library: its C header files refer to those of
3123 the GNU MPFR library, which in turn refer to those of the GMP library.
3124 Thus, when installing MPC, the MPFR and GMP libraries also get installed
3125 in the profile; removing MPC also removes MPFR and GMP---unless they had
3126 also been explicitly installed by the user.
3128 Besides, packages sometimes rely on the definition of environment
3129 variables for their search paths (see explanation of
3130 @option{--search-paths} below). Any missing or possibly incorrect
3131 environment variable definitions are reported here.
3133 @item --install-from-expression=@var{exp}
3135 Install the package @var{exp} evaluates to.
3137 @var{exp} must be a Scheme expression that evaluates to a
3138 @code{<package>} object. This option is notably useful to disambiguate
3139 between same-named variants of a package, with expressions such as
3140 @code{(@@ (gnu packages base) guile-final)}.
3142 Note that this option installs the first output of the specified
3143 package, which may be insufficient when needing a specific output of a
3144 multiple-output package.
3146 @item --install-from-file=@var{file}
3147 @itemx -f @var{file}
3148 Install the package that the code within @var{file} evaluates to.
3150 As an example, @var{file} might contain a definition like this
3151 (@pxref{Defining Packages}):
3154 @include package-hello.scm
3157 Developers may find it useful to include such a @file{guix.scm} file
3158 in the root of their project source tree that can be used to test
3159 development snapshots and create reproducible development environments
3160 (@pxref{Invoking guix environment}).
3162 The @var{file} may also contain a JSON representation of one or more
3163 package definitions. Running @code{guix package -f} on
3164 @file{hello.json} with the following contents would result in installing
3165 the package @code{greeter} after building @code{myhello}:
3168 @verbatiminclude package-hello.json
3171 @item --remove=@var{package} @dots{}
3172 @itemx -r @var{package} @dots{}
3173 Remove the specified @var{package}s.
3175 As for @option{--install}, each @var{package} may specify a version number
3176 and/or output name in addition to the package name. For instance,
3177 @samp{-r glibc:debug} would remove the @code{debug} output of
3180 @item --upgrade[=@var{regexp} @dots{}]
3181 @itemx -u [@var{regexp} @dots{}]
3182 @cindex upgrading packages
3183 Upgrade all the installed packages. If one or more @var{regexp}s are
3184 specified, upgrade only installed packages whose name matches a
3185 @var{regexp}. Also see the @option{--do-not-upgrade} option below.
3187 Note that this upgrades package to the latest version of packages found
3188 in the distribution currently installed. To update your distribution,
3189 you should regularly run @command{guix pull} (@pxref{Invoking guix
3192 @cindex package transformations, upgrades
3193 When upgrading, package transformations that were originally applied
3194 when creating the profile are automatically re-applied (@pxref{Package
3195 Transformation Options}). For example, assume you first installed Emacs
3196 from the tip of its development branch with:
3199 guix install emacs-next --with-branch=emacs-next=master
3202 Next time you run @command{guix upgrade}, Guix will again pull the tip
3203 of the Emacs development branch and build @code{emacs-next} from that
3206 Note that transformation options such as @option{--with-branch} and
3207 @option{--with-source} depend on external state; it is up to you to
3208 ensure that they work as expected. You can also discard a
3209 transformations that apply to a package by running:
3212 guix install @var{package}
3215 @item --do-not-upgrade[=@var{regexp} @dots{}]
3216 When used together with the @option{--upgrade} option, do @emph{not}
3217 upgrade any packages whose name matches a @var{regexp}. For example, to
3218 upgrade all packages in the current profile except those containing the
3219 substring ``emacs'':
3222 $ guix package --upgrade . --do-not-upgrade emacs
3225 @item @anchor{profile-manifest}--manifest=@var{file}
3226 @itemx -m @var{file}
3227 @cindex profile declaration
3228 @cindex profile manifest
3229 Create a new generation of the profile from the manifest object
3230 returned by the Scheme code in @var{file}. This option can be repeated
3231 several times, in which case the manifests are concatenated.
3233 This allows you to @emph{declare} the profile's contents rather than
3234 constructing it through a sequence of @option{--install} and similar
3235 commands. The advantage is that @var{file} can be put under version
3236 control, copied to different machines to reproduce the same profile, and
3239 @c FIXME: Add reference to (guix profile) documentation when available.
3240 @var{file} must return a @dfn{manifest} object, which is roughly a list
3243 @findex packages->manifest
3245 (use-package-modules guile emacs)
3250 ;; Use a specific package output.
3251 (list guile-2.0 "debug")))
3254 @findex specifications->manifest
3255 In this example we have to know which modules define the @code{emacs}
3256 and @code{guile-2.0} variables to provide the right
3257 @code{use-package-modules} line, which can be cumbersome. We can
3258 instead provide regular package specifications and let
3259 @code{specifications->manifest} look up the corresponding package
3263 (specifications->manifest
3264 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
3268 @cindex rolling back
3269 @cindex undoing transactions
3270 @cindex transactions, undoing
3271 Roll back to the previous @dfn{generation} of the profile---i.e., undo
3272 the last transaction.
3274 When combined with options such as @option{--install}, roll back occurs
3275 before any other actions.
3277 When rolling back from the first generation that actually contains
3278 installed packages, the profile is made to point to the @dfn{zeroth
3279 generation}, which contains no files apart from its own metadata.
3281 After having rolled back, installing, removing, or upgrading packages
3282 overwrites previous future generations. Thus, the history of the
3283 generations in a profile is always linear.
3285 @item --switch-generation=@var{pattern}
3286 @itemx -S @var{pattern}
3288 Switch to a particular generation defined by @var{pattern}.
3290 @var{pattern} may be either a generation number or a number prefixed
3291 with ``+'' or ``-''. The latter means: move forward/backward by a
3292 specified number of generations. For example, if you want to return to
3293 the latest generation after @option{--roll-back}, use
3294 @option{--switch-generation=+1}.
3296 The difference between @option{--roll-back} and
3297 @option{--switch-generation=-1} is that @option{--switch-generation} will
3298 not make a zeroth generation, so if a specified generation does not
3299 exist, the current generation will not be changed.
3301 @item --search-paths[=@var{kind}]
3302 @cindex search paths
3303 Report environment variable definitions, in Bash syntax, that may be
3304 needed in order to use the set of installed packages. These environment
3305 variables are used to specify @dfn{search paths} for files used by some
3306 of the installed packages.
3308 For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
3309 environment variables to be defined so it can look for headers and
3310 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
3311 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
3312 library are installed in the profile, then @option{--search-paths} will
3313 suggest setting these variables to @file{@var{profile}/include} and
3314 @file{@var{profile}/lib}, respectively.
3316 The typical use case is to define these environment variables in the
3320 $ eval `guix package --search-paths`
3323 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
3324 meaning that the returned environment variable definitions will either
3325 be exact settings, or prefixes or suffixes of the current value of these
3326 variables. When omitted, @var{kind} defaults to @code{exact}.
3328 This option can also be used to compute the @emph{combined} search paths
3329 of several profiles. Consider this example:
3332 $ guix package -p foo -i guile
3333 $ guix package -p bar -i guile-json
3334 $ guix package -p foo -p bar --search-paths
3337 The last command above reports about the @env{GUILE_LOAD_PATH}
3338 variable, even though, taken individually, neither @file{foo} nor
3339 @file{bar} would lead to that recommendation.
3342 @item --profile=@var{profile}
3343 @itemx -p @var{profile}
3344 Use @var{profile} instead of the user's default profile.
3346 @var{profile} must be the name of a file that will be created upon
3347 completion. Concretely, @var{profile} will be a mere symbolic link
3348 (``symlink'') pointing to the actual profile where packages are
3352 $ guix install hello -p ~/code/my-profile
3354 $ ~/code/my-profile/bin/hello
3358 All it takes to get rid of the profile is to remove this symlink and its
3359 siblings that point to specific generations:
3362 $ rm ~/code/my-profile ~/code/my-profile-*-link
3365 @item --list-profiles
3366 List all the user's profiles:
3369 $ guix package --list-profiles
3370 /home/charlie/.guix-profile
3371 /home/charlie/code/my-profile
3372 /home/charlie/code/devel-profile
3373 /home/charlie/tmp/test
3376 When running as root, list all the profiles of all the users.
3378 @cindex collisions, in a profile
3379 @cindex colliding packages in profiles
3380 @cindex profile collisions
3381 @item --allow-collisions
3382 Allow colliding packages in the new profile. Use at your own risk!
3384 By default, @command{guix package} reports as an error @dfn{collisions}
3385 in the profile. Collisions happen when two or more different versions
3386 or variants of a given package end up in the profile.
3389 Use the bootstrap Guile to build the profile. This option is only
3390 useful to distribution developers.
3394 In addition to these actions, @command{guix package} supports the
3395 following options to query the current state of a profile, or the
3396 availability of packages:
3400 @item --search=@var{regexp}
3401 @itemx -s @var{regexp}
3402 @anchor{guix-search}
3403 @cindex searching for packages
3404 List the available packages whose name, synopsis, or description matches
3405 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3406 Print all the metadata of matching packages in
3407 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3408 GNU recutils manual}).
3410 This allows specific fields to be extracted using the @command{recsel}
3411 command, for instance:
3414 $ guix package -s malloc | recsel -p name,version,relevance
3428 Similarly, to show the name of all the packages available under the
3429 terms of the GNU@tie{}LGPL version 3:
3432 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3439 It is also possible to refine search results using several @code{-s} flags to
3440 @command{guix package}, or several arguments to @command{guix search}. For
3441 example, the following command returns a list of board games (this time using
3442 the @command{guix search} alias):
3445 $ guix search '\<board\>' game | recsel -p name
3450 If we were to omit @code{-s game}, we would also get software packages
3451 that deal with printed circuit boards; removing the angle brackets
3452 around @code{board} would further add packages that have to do with
3455 And now for a more elaborate example. The following command searches
3456 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3457 libraries, and prints the name and synopsis of the matching packages:
3460 $ guix search crypto library | \
3461 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3465 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3466 information on @dfn{selection expressions} for @code{recsel -e}.
3468 @item --show=@var{package}
3469 Show details about @var{package}, taken from the list of available packages, in
3470 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3474 $ guix package --show=python | recsel -p name,version
3482 You may also specify the full name of a package to only get details about a
3483 specific version of it (this time using the @command{guix show} alias):
3485 $ guix show python@@3.4 | recsel -p name,version
3492 @item --list-installed[=@var{regexp}]
3493 @itemx -I [@var{regexp}]
3494 List the currently installed packages in the specified profile, with the
3495 most recently installed packages shown last. When @var{regexp} is
3496 specified, list only installed packages whose name matches @var{regexp}.
3498 For each installed package, print the following items, separated by
3499 tabs: the package name, its version string, the part of the package that
3500 is installed (for instance, @code{out} for the default output,
3501 @code{include} for its headers, etc.), and the path of this package in
3504 @item --list-available[=@var{regexp}]
3505 @itemx -A [@var{regexp}]
3506 List packages currently available in the distribution for this system
3507 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3508 available packages whose name matches @var{regexp}.
3510 For each package, print the following items separated by tabs: its name,
3511 its version string, the parts of the package (@pxref{Packages with
3512 Multiple Outputs}), and the source location of its definition.
3514 @item --list-generations[=@var{pattern}]
3515 @itemx -l [@var{pattern}]
3517 Return a list of generations along with their creation dates; for each
3518 generation, show the installed packages, with the most recently
3519 installed packages shown last. Note that the zeroth generation is never
3522 For each installed package, print the following items, separated by
3523 tabs: the name of a package, its version string, the part of the package
3524 that is installed (@pxref{Packages with Multiple Outputs}), and the
3525 location of this package in the store.
3527 When @var{pattern} is used, the command returns only matching
3528 generations. Valid patterns include:
3531 @item @emph{Integers and comma-separated integers}. Both patterns denote
3532 generation numbers. For instance, @option{--list-generations=1} returns
3535 And @option{--list-generations=1,8,2} outputs three generations in the
3536 specified order. Neither spaces nor trailing commas are allowed.
3538 @item @emph{Ranges}. @option{--list-generations=2..9} prints the
3539 specified generations and everything in between. Note that the start of
3540 a range must be smaller than its end.
3542 It is also possible to omit the endpoint. For example,
3543 @option{--list-generations=2..}, returns all generations starting from the
3546 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3547 or months by passing an integer along with the first letter of the
3548 duration. For example, @option{--list-generations=20d} lists generations
3549 that are up to 20 days old.
3552 @item --delete-generations[=@var{pattern}]
3553 @itemx -d [@var{pattern}]
3554 When @var{pattern} is omitted, delete all generations except the current
3557 This command accepts the same patterns as @option{--list-generations}.
3558 When @var{pattern} is specified, delete the matching generations. When
3559 @var{pattern} specifies a duration, generations @emph{older} than the
3560 specified duration match. For instance, @option{--delete-generations=1m}
3561 deletes generations that are more than one month old.
3563 If the current generation matches, it is @emph{not} deleted. Also, the
3564 zeroth generation is never deleted.
3566 Note that deleting generations prevents rolling back to them.
3567 Consequently, this command must be used with care.
3571 Finally, since @command{guix package} may actually start build
3572 processes, it supports all the common build options (@pxref{Common Build
3573 Options}). It also supports package transformation options, such as
3574 @option{--with-source} (@pxref{Package Transformation Options}).
3575 However, note that package transformations are lost when upgrading; to
3576 preserve transformations across upgrades, you should define your own
3577 package variant in a Guile module and add it to @env{GUIX_PACKAGE_PATH}
3578 (@pxref{Defining Packages}).
3581 @section Substitutes
3584 @cindex pre-built binaries
3585 Guix supports transparent source/binary deployment, which means that it
3586 can either build things locally, or download pre-built items from a
3587 server, or both. We call these pre-built items @dfn{substitutes}---they
3588 are substitutes for local build results. In many cases, downloading a
3589 substitute is much faster than building things locally.
3591 Substitutes can be anything resulting from a derivation build
3592 (@pxref{Derivations}). Of course, in the common case, they are
3593 pre-built package binaries, but source tarballs, for instance, which
3594 also result from derivation builds, can be available as substitutes.
3597 * Official Substitute Server:: One particular source of substitutes.
3598 * Substitute Server Authorization:: How to enable or disable substitutes.
3599 * Getting Substitutes from Other Servers:: Substitute diversity.
3600 * Substitute Authentication:: How Guix verifies substitutes.
3601 * Proxy Settings:: How to get substitutes via proxy.
3602 * Substitution Failure:: What happens when substitution fails.
3603 * On Trusting Binaries:: How can you trust that binary blob?
3606 @node Official Substitute Server
3607 @subsection Official Substitute Server
3610 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3611 that builds packages from Guix continuously for some
3612 architectures, and makes them available as substitutes. This is the
3613 default source of substitutes; it can be overridden by passing the
3614 @option{--substitute-urls} option either to @command{guix-daemon}
3615 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3616 or to client tools such as @command{guix package}
3617 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3620 Substitute URLs can be either HTTP or HTTPS.
3621 HTTPS is recommended because communications are encrypted; conversely,
3622 using HTTP makes all communications visible to an eavesdropper, who
3623 could use the information gathered to determine, for instance, whether
3624 your system has unpatched security vulnerabilities.
3626 Substitutes from the official build farm are enabled by default when
3627 using Guix System (@pxref{GNU Distribution}). However,
3628 they are disabled by default when using Guix on a foreign distribution,
3629 unless you have explicitly enabled them via one of the recommended
3630 installation steps (@pxref{Installation}). The following paragraphs
3631 describe how to enable or disable substitutes for the official build
3632 farm; the same procedure can also be used to enable substitutes for any
3633 other substitute server.
3635 @node Substitute Server Authorization
3636 @subsection Substitute Server Authorization
3639 @cindex substitutes, authorization thereof
3640 @cindex access control list (ACL), for substitutes
3641 @cindex ACL (access control list), for substitutes
3642 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3644 must add its public key to the access control list (ACL) of archive
3645 imports, using the @command{guix archive} command (@pxref{Invoking guix
3646 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3647 be compromised and to serve genuine substitutes.
3650 If you are using Guix System, you can skip this section: Guix System
3651 authorizes substitutes from @code{@value{SUBSTITUTE-SERVER}} by default.
3654 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3655 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3656 the installation prefix of Guix. If you installed Guix from source,
3657 make sure you checked the GPG signature of
3658 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3659 Then, you can run something like this:
3662 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3665 Once this is in place, the output of a command like @code{guix build}
3666 should change from something like:
3669 $ guix build emacs --dry-run
3670 The following derivations would be built:
3671 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3672 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3673 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3674 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3682 $ guix build emacs --dry-run
3683 112.3 MB would be downloaded:
3684 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3685 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3686 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3687 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3692 The text changed from ``The following derivations would be built'' to
3693 ``112.3 MB would be downloaded''. This indicates that substitutes from
3694 @code{@value{SUBSTITUTE-SERVER}} are usable and will be downloaded, when
3695 possible, for future builds.
3697 @cindex substitutes, how to disable
3698 The substitute mechanism can be disabled globally by running
3699 @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
3700 guix-daemon}). It can also be disabled temporarily by passing the
3701 @option{--no-substitutes} option to @command{guix package},
3702 @command{guix build}, and other command-line tools.
3704 @node Getting Substitutes from Other Servers
3705 @subsection Getting Substitutes from Other Servers
3707 @cindex substitute servers, adding more
3708 Guix can look up and fetch substitutes from several servers. This is
3709 useful when you are using packages from additional channels for which
3710 the official server does not have substitutes but another server
3711 provides them. Another situation where this is useful is when you would
3712 prefer to download from your organization's substitute server, resorting
3713 to the official server only as a fallback or dismissing it altogether.
3715 You can give Guix a list of substitute server URLs and it will check
3716 them in the specified order. You also need to explicitly authorize the
3717 public keys of substitute servers to instruct Guix to accept the
3718 substitutes they sign.
3720 On Guix System, this is achieved by modifying the configuration of the
3721 @code{guix} service. Since the @code{guix} service is part of the
3722 default lists of services, @code{%base-services} and
3723 @code{%desktop-services}, you can use @code{modify-services} to change
3724 its configuration and add the URLs and substitute keys that you want
3725 (@pxref{Service Reference, @code{modify-services}}).
3727 As an example, suppose you want to fetch substitutes from
3728 @code{guix.example.org} and to authorize the signing key of that server,
3729 in addition to the default @code{@value{SUBSTITUTE-SERVER}}. The
3730 resulting operating system configuration will look something like:
3736 ;; Assume we're starting from '%desktop-services'. Replace it
3737 ;; with the list of services you're actually using.
3738 (modify-services %desktop-services
3739 (guix-service-type config =>
3743 (append (list "https://guix.example.org")
3744 %default-substitute-urls))
3746 (append (list (local-file "./key.pub"))
3747 %default-authorized-guix-keys)))))))
3750 This assumes that the file @file{key.pub} contains the signing key of
3751 @code{guix.example.org}. With this change in place in your operating
3752 system configuration file (say @file{/etc/config.scm}), you can
3753 reconfigure and restart the @code{guix-daemon} service or reboot so the
3754 changes take effect:
3757 $ sudo guix system reconfigure /etc/config.scm
3758 $ sudo herd restart guix-daemon
3761 If you're running Guix on a ``foreign distro'', you would instead take
3762 the following steps to get substitutes from additional servers:
3766 Edit the service configuration file for @code{guix-daemon}; when using
3767 systemd, this is normally
3768 @file{/etc/systemd/system/guix-daemon.service}. Add the
3769 @option{--substitute-urls} option on the @command{guix-daemon} command
3770 line and list the URLs of interest (@pxref{daemon-substitute-urls,
3771 @code{guix-daemon --substitute-urls}}):
3774 @dots{} --substitute-urls='https://guix.example.org https://@value{SUBSTITUTE-SERVER}'
3778 Restart the daemon. For systemd, it goes like this:
3781 systemctl daemon-reload
3782 systemctl restart guix-daemon.service
3786 Authorize the key of the new server (@pxref{Invoking guix archive}):
3789 guix archive --authorize < key.pub
3792 Again this assumes @file{key.pub} contains the public key that
3793 @code{guix.example.org} uses to sign substitutes.
3796 Now you're all set! Substitutes will be preferably taken from
3797 @code{https://guix.example.org}, using @code{@value{SUBSTITUTE-SERVER}}
3798 as a fallback. Of course you can list as many substitute servers as you
3799 like, with the caveat that substitute lookup can be slowed down if too
3800 many servers need to be contacted.
3802 Note that there are also situations where one may want to add the URL of
3803 a substitute server @emph{without} authorizing its key.
3804 @xref{Substitute Authentication}, to understand this fine point.
3806 @node Substitute Authentication
3807 @subsection Substitute Authentication
3809 @cindex digital signatures
3810 Guix detects and raises an error when attempting to use a substitute
3811 that has been tampered with. Likewise, it ignores substitutes that are
3812 not signed, or that are not signed by one of the keys listed in the ACL.
3814 There is one exception though: if an unauthorized server provides
3815 substitutes that are @emph{bit-for-bit identical} to those provided by
3816 an authorized server, then the unauthorized server becomes eligible for
3817 downloads. For example, assume we have chosen two substitute servers
3821 --substitute-urls="https://a.example.org https://b.example.org"
3825 @cindex reproducible builds
3826 If the ACL contains only the key for @samp{b.example.org}, and if
3827 @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
3828 then Guix will download substitutes from @samp{a.example.org} because it
3829 comes first in the list and can be considered a mirror of
3830 @samp{b.example.org}. In practice, independent build machines usually
3831 produce the same binaries, thanks to bit-reproducible builds (see
3834 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3835 (in other words, the server is not authenticated), contrary to what
3836 HTTPS clients such as Web browsers usually do. This is because Guix
3837 authenticates substitute information itself, as explained above, which
3838 is what we care about (whereas X.509 certificates are about
3839 authenticating bindings between domain names and public keys).
3841 @node Proxy Settings
3842 @subsection Proxy Settings
3846 Substitutes are downloaded over HTTP or HTTPS. The @env{http_proxy} and
3847 @env{https_proxy} environment variables can be set in the environment of
3848 @command{guix-daemon} and are honored for downloads of substitutes.
3849 Note that the value of those environment variables in the environment
3850 where @command{guix build}, @command{guix package}, and other client
3851 commands are run has @emph{absolutely no effect}.
3853 @node Substitution Failure
3854 @subsection Substitution Failure
3856 Even when a substitute for a derivation is available, sometimes the
3857 substitution attempt will fail. This can happen for a variety of
3858 reasons: the substitute server might be offline, the substitute may
3859 recently have been deleted, the connection might have been interrupted,
3862 When substitutes are enabled and a substitute for a derivation is
3863 available, but the substitution attempt fails, Guix will attempt to
3864 build the derivation locally depending on whether or not
3865 @option{--fallback} was given (@pxref{fallback-option,, common build
3866 option @option{--fallback}}). Specifically, if @option{--fallback} was
3867 omitted, then no local build will be performed, and the derivation is
3868 considered to have failed. However, if @option{--fallback} was given,
3869 then Guix will attempt to build the derivation locally, and the success
3870 or failure of the derivation depends on the success or failure of the
3871 local build. Note that when substitutes are disabled or no substitute
3872 is available for the derivation in question, a local build will
3873 @emph{always} be performed, regardless of whether or not
3874 @option{--fallback} was given.
3876 To get an idea of how many substitutes are available right now, you can
3877 try running the @command{guix weather} command (@pxref{Invoking guix
3878 weather}). This command provides statistics on the substitutes provided
3881 @node On Trusting Binaries
3882 @subsection On Trusting Binaries
3884 @cindex trust, of pre-built binaries
3885 Today, each individual's control over their own computing is at the
3886 mercy of institutions, corporations, and groups with enough power and
3887 determination to subvert the computing infrastructure and exploit its
3888 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3889 convenient, we encourage users to also build on their own, or even run
3890 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3891 interesting target. One way to help is by publishing the software you
3892 build using @command{guix publish} so that others have one more choice
3893 of server to download substitutes from (@pxref{Invoking guix publish}).
3895 Guix has the foundations to maximize build reproducibility
3896 (@pxref{Features}). In most cases, independent builds of a given
3897 package or derivation should yield bit-identical results. Thus, through
3898 a diverse set of independent package builds, we can strengthen the
3899 integrity of our systems. The @command{guix challenge} command aims to
3900 help users assess substitute servers, and to assist developers in
3901 finding out about non-deterministic package builds (@pxref{Invoking guix
3902 challenge}). Similarly, the @option{--check} option of @command{guix
3903 build} allows users to check whether previously-installed substitutes
3904 are genuine by rebuilding them locally (@pxref{build-check,
3905 @command{guix build --check}}).
3907 In the future, we want Guix to have support to publish and retrieve
3908 binaries to/from other users, in a peer-to-peer fashion. If you would
3909 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3911 @node Packages with Multiple Outputs
3912 @section Packages with Multiple Outputs
3914 @cindex multiple-output packages
3915 @cindex package outputs
3918 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3919 source package leads to exactly one directory in the store. When running
3920 @command{guix install glibc}, one installs the default output of the
3921 GNU libc package; the default output is called @code{out}, but its name
3922 can be omitted as shown in this command. In this particular case, the
3923 default output of @code{glibc} contains all the C header files, shared
3924 libraries, static libraries, Info documentation, and other supporting
3927 Sometimes it is more appropriate to separate the various types of files
3928 produced from a single source package into separate outputs. For
3929 instance, the GLib C library (used by GTK+ and related packages)
3930 installs more than 20 MiB of reference documentation as HTML pages.
3931 To save space for users who do not need it, the documentation goes to a
3932 separate output, called @code{doc}. To install the main GLib output,
3933 which contains everything but the documentation, one would run:
3939 @cindex documentation
3940 The command to install its documentation is:
3943 guix install glib:doc
3946 Some packages install programs with different ``dependency footprints''.
3947 For instance, the WordNet package installs both command-line tools and
3948 graphical user interfaces (GUIs). The former depend solely on the C
3949 library, whereas the latter depend on Tcl/Tk and the underlying X
3950 libraries. In this case, we leave the command-line tools in the default
3951 output, whereas the GUIs are in a separate output. This allows users
3952 who do not need the GUIs to save space. The @command{guix size} command
3953 can help find out about such situations (@pxref{Invoking guix size}).
3954 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3956 There are several such multiple-output packages in the GNU distribution.
3957 Other conventional output names include @code{lib} for libraries and
3958 possibly header files, @code{bin} for stand-alone programs, and
3959 @code{debug} for debugging information (@pxref{Installing Debugging
3960 Files}). The outputs of a packages are listed in the third column of
3961 the output of @command{guix package --list-available} (@pxref{Invoking
3965 @node Invoking guix gc
3966 @section Invoking @command{guix gc}
3968 @cindex garbage collector
3970 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3971 The @command{guix gc} command allows users to explicitly run the garbage
3972 collector to reclaim space from the @file{/gnu/store} directory. It is
3973 the @emph{only} way to remove files from @file{/gnu/store}---removing
3974 files or directories manually may break it beyond repair!
3977 @cindex garbage collector roots
3978 The garbage collector has a set of known @dfn{roots}: any file under
3979 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3980 cannot be deleted; any other file is considered @dfn{dead} and may be
3981 deleted. The set of garbage collector roots (``GC roots'' for short)
3982 includes default user profiles; by default, the symlinks under
3983 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3984 added with @command{guix build --root}, for example (@pxref{Invoking
3985 guix build}). The @command{guix gc --list-roots} command lists them.
3987 Prior to running @code{guix gc --collect-garbage} to make space, it is
3988 often useful to remove old generations from user profiles; that way, old
3989 package builds referenced by those generations can be reclaimed. This
3990 is achieved by running @code{guix package --delete-generations}
3991 (@pxref{Invoking guix package}).
3993 Our recommendation is to run a garbage collection periodically, or when
3994 you are short on disk space. For instance, to guarantee that at least
3995 5@tie{}GB are available on your disk, simply run:
4001 It is perfectly safe to run as a non-interactive periodic job
4002 (@pxref{Scheduled Job Execution}, for how to set up such a job).
4003 Running @command{guix gc} with no arguments will collect as
4004 much garbage as it can, but that is often inconvenient: you may find
4005 yourself having to rebuild or re-download software that is ``dead'' from
4006 the GC viewpoint but that is necessary to build other pieces of
4007 software---e.g., the compiler tool chain.
4009 The @command{guix gc} command has three modes of operation: it can be
4010 used to garbage-collect any dead files (the default), to delete specific
4011 files (the @option{--delete} option), to print garbage-collector
4012 information, or for more advanced queries. The garbage collection
4013 options are as follows:
4016 @item --collect-garbage[=@var{min}]
4017 @itemx -C [@var{min}]
4018 Collect garbage---i.e., unreachable @file{/gnu/store} files and
4019 sub-directories. This is the default operation when no option is
4022 When @var{min} is given, stop once @var{min} bytes have been collected.
4023 @var{min} may be a number of bytes, or it may include a unit as a
4024 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
4025 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
4027 When @var{min} is omitted, collect all the garbage.
4029 @item --free-space=@var{free}
4030 @itemx -F @var{free}
4031 Collect garbage until @var{free} space is available under
4032 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
4033 as @code{500MiB}, as described above.
4035 When @var{free} or more is already available in @file{/gnu/store}, do
4036 nothing and exit immediately.
4038 @item --delete-generations[=@var{duration}]
4039 @itemx -d [@var{duration}]
4040 Before starting the garbage collection process, delete all the generations
4041 older than @var{duration}, for all the user profiles; when run as root, this
4042 applies to all the profiles @emph{of all the users}.
4044 For example, this command deletes all the generations of all your profiles
4045 that are older than 2 months (except generations that are current), and then
4046 proceeds to free space until at least 10 GiB are available:
4049 guix gc -d 2m -F 10G
4054 Attempt to delete all the store files and directories specified as
4055 arguments. This fails if some of the files are not in the store, or if
4056 they are still live.
4058 @item --list-failures
4059 List store items corresponding to cached build failures.
4061 This prints nothing unless the daemon was started with
4062 @option{--cache-failures} (@pxref{Invoking guix-daemon,
4063 @option{--cache-failures}}).
4066 List the GC roots owned by the user; when run as root, list @emph{all} the GC
4070 List store items in use by currently running processes. These store
4071 items are effectively considered GC roots: they cannot be deleted.
4073 @item --clear-failures
4074 Remove the specified store items from the failed-build cache.
4076 Again, this option only makes sense when the daemon is started with
4077 @option{--cache-failures}. Otherwise, it does nothing.
4080 Show the list of dead files and directories still present in the
4081 store---i.e., files and directories no longer reachable from any root.
4084 Show the list of live store files and directories.
4088 In addition, the references among existing store files can be queried:
4094 @cindex package dependencies
4095 List the references (respectively, the referrers) of store files given
4101 List the requisites of the store files passed as arguments. Requisites
4102 include the store files themselves, their references, and the references
4103 of these, recursively. In other words, the returned list is the
4104 @dfn{transitive closure} of the store files.
4106 @xref{Invoking guix size}, for a tool to profile the size of the closure
4107 of an element. @xref{Invoking guix graph}, for a tool to visualize
4108 the graph of references.
4112 Return the derivation(s) leading to the given store items
4113 (@pxref{Derivations}).
4115 For example, this command:
4118 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
4122 returns the @file{.drv} file(s) leading to the @code{emacs} package
4123 installed in your profile.
4125 Note that there may be zero matching @file{.drv} files, for instance
4126 because these files have been garbage-collected. There can also be more
4127 than one matching @file{.drv} due to fixed-output derivations.
4130 Lastly, the following options allow you to check the integrity of the
4131 store and to control disk usage.
4135 @item --verify[=@var{options}]
4136 @cindex integrity, of the store
4137 @cindex integrity checking
4138 Verify the integrity of the store.
4140 By default, make sure that all the store items marked as valid in the
4141 database of the daemon actually exist in @file{/gnu/store}.
4143 When provided, @var{options} must be a comma-separated list containing one
4144 or more of @code{contents} and @code{repair}.
4146 When passing @option{--verify=contents}, the daemon computes the
4147 content hash of each store item and compares it against its hash in the
4148 database. Hash mismatches are reported as data corruptions. Because it
4149 traverses @emph{all the files in the store}, this command can take a
4150 long time, especially on systems with a slow disk drive.
4152 @cindex repairing the store
4153 @cindex corruption, recovering from
4154 Using @option{--verify=repair} or @option{--verify=contents,repair}
4155 causes the daemon to try to repair corrupt store items by fetching
4156 substitutes for them (@pxref{Substitutes}). Because repairing is not
4157 atomic, and thus potentially dangerous, it is available only to the
4158 system administrator. A lightweight alternative, when you know exactly
4159 which items in the store are corrupt, is @command{guix build --repair}
4160 (@pxref{Invoking guix build}).
4163 @cindex deduplication
4164 Optimize the store by hard-linking identical files---this is
4165 @dfn{deduplication}.
4167 The daemon performs deduplication after each successful build or archive
4168 import, unless it was started with @option{--disable-deduplication}
4169 (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
4170 this option is primarily useful when the daemon was running with
4171 @option{--disable-deduplication}.
4175 @node Invoking guix pull
4176 @section Invoking @command{guix pull}
4178 @cindex upgrading Guix
4179 @cindex updating Guix
4180 @cindex @command{guix pull}
4182 @cindex security, @command{guix pull}
4183 @cindex authenticity, of code obtained with @command{guix pull}
4184 Packages are installed or upgraded to the latest version available in
4185 the distribution currently available on your local machine. To update
4186 that distribution, along with the Guix tools, you must run @command{guix
4187 pull}: the command downloads the latest Guix source code and package
4188 descriptions, and deploys it. Source code is downloaded from a
4189 @uref{https://git-scm.com, Git} repository, by default the official
4190 GNU@tie{}Guix repository, though this can be customized. @command{guix
4191 pull} ensures that the code it downloads is @emph{authentic} by
4192 verifying that commits are signed by Guix developers.
4194 Specifically, @command{guix pull} downloads code from the @dfn{channels}
4195 (@pxref{Channels}) specified by one of the followings, in this order:
4199 the @option{--channels} option;
4201 the user's @file{~/.config/guix/channels.scm} file;
4203 the system-wide @file{/etc/guix/channels.scm} file;
4205 the built-in default channels specified in the @code{%default-channels}
4209 On completion, @command{guix package} will use packages and package
4210 versions from this just-retrieved copy of Guix. Not only that, but all
4211 the Guix commands and Scheme modules will also be taken from that latest
4212 version. New @command{guix} sub-commands added by the update also
4215 Any user can update their Guix copy using @command{guix pull}, and the
4216 effect is limited to the user who ran @command{guix pull}. For
4217 instance, when user @code{root} runs @command{guix pull}, this has no
4218 effect on the version of Guix that user @code{alice} sees, and vice
4221 The result of running @command{guix pull} is a @dfn{profile} available
4222 under @file{~/.config/guix/current} containing the latest Guix. Thus,
4223 make sure to add it to the beginning of your search path so that you use
4224 the latest version, and similarly for the Info manual
4225 (@pxref{Documentation}):
4228 export PATH="$HOME/.config/guix/current/bin:$PATH"
4229 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
4232 The @option{--list-generations} or @option{-l} option lists past generations
4233 produced by @command{guix pull}, along with details about their provenance:
4237 Generation 1 Jun 10 2018 00:18:18
4239 repository URL: https://git.savannah.gnu.org/git/guix.git
4240 branch: origin/master
4241 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
4243 Generation 2 Jun 11 2018 11:02:49
4245 repository URL: https://git.savannah.gnu.org/git/guix.git
4246 branch: origin/master
4247 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
4248 2 new packages: keepalived, libnfnetlink
4249 6 packages upgraded: emacs-nix-mode@@2.0.4,
4250 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
4251 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
4253 Generation 3 Jun 13 2018 23:31:07 (current)
4255 repository URL: https://git.savannah.gnu.org/git/guix.git
4256 branch: origin/master
4257 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
4258 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
4259 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
4262 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
4263 describe the current status of Guix.
4265 This @code{~/.config/guix/current} profile works exactly like the profiles
4266 created by @command{guix package} (@pxref{Invoking guix package}). That
4267 is, you can list generations, roll back to the previous
4268 generation---i.e., the previous Guix---and so on:
4271 $ guix pull --roll-back
4272 switched from generation 3 to 2
4273 $ guix pull --delete-generations=1
4274 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4277 You can also use @command{guix package} (@pxref{Invoking guix package})
4278 to manage the profile by naming it explicitly:
4280 $ guix package -p ~/.config/guix/current --roll-back
4281 switched from generation 3 to 2
4282 $ guix package -p ~/.config/guix/current --delete-generations=1
4283 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4286 The @command{guix pull} command is usually invoked with no arguments,
4287 but it supports the following options:
4290 @item --url=@var{url}
4291 @itemx --commit=@var{commit}
4292 @itemx --branch=@var{branch}
4293 Download code for the @code{guix} channel from the specified @var{url}, at the
4294 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4295 string), or @var{branch}.
4297 @cindex @file{channels.scm}, configuration file
4298 @cindex configuration file for channels
4299 These options are provided for convenience, but you can also specify your
4300 configuration in the @file{~/.config/guix/channels.scm} file or using the
4301 @option{--channels} option (see below).
4303 @item --channels=@var{file}
4304 @itemx -C @var{file}
4305 Read the list of channels from @var{file} instead of
4306 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
4307 @var{file} must contain Scheme code that
4308 evaluates to a list of channel objects. @xref{Channels}, for more
4311 @cindex channel news
4314 Display the list of packages added or upgraded since the previous
4315 generation, as well as, occasionally, news written by channel authors
4316 for their users (@pxref{Channels, Writing Channel News}).
4318 The package information is the same as displayed upon @command{guix
4319 pull} completion, but without ellipses; it is also similar to the output
4320 of @command{guix pull -l} for the last generation (see below).
4322 @item --list-generations[=@var{pattern}]
4323 @itemx -l [@var{pattern}]
4324 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
4325 is provided, the subset of generations that match @var{pattern}.
4326 The syntax of @var{pattern} is the same as with @code{guix package
4327 --list-generations} (@pxref{Invoking guix package}).
4330 @cindex rolling back
4331 @cindex undoing transactions
4332 @cindex transactions, undoing
4333 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
4334 undo the last transaction.
4336 @item --switch-generation=@var{pattern}
4337 @itemx -S @var{pattern}
4339 Switch to a particular generation defined by @var{pattern}.
4341 @var{pattern} may be either a generation number or a number prefixed
4342 with ``+'' or ``-''. The latter means: move forward/backward by a
4343 specified number of generations. For example, if you want to return to
4344 the latest generation after @option{--roll-back}, use
4345 @option{--switch-generation=+1}.
4347 @item --delete-generations[=@var{pattern}]
4348 @itemx -d [@var{pattern}]
4349 When @var{pattern} is omitted, delete all generations except the current
4352 This command accepts the same patterns as @option{--list-generations}.
4353 When @var{pattern} is specified, delete the matching generations. When
4354 @var{pattern} specifies a duration, generations @emph{older} than the
4355 specified duration match. For instance, @option{--delete-generations=1m}
4356 deletes generations that are more than one month old.
4358 If the current generation matches, it is @emph{not} deleted.
4360 Note that deleting generations prevents rolling back to them.
4361 Consequently, this command must be used with care.
4363 @xref{Invoking guix describe}, for a way to display information about the
4364 current generation only.
4366 @item --profile=@var{profile}
4367 @itemx -p @var{profile}
4368 Use @var{profile} instead of @file{~/.config/guix/current}.
4372 Show which channel commit(s) would be used and what would be built or
4373 substituted but do not actually do it.
4375 @item --allow-downgrades
4376 Allow pulling older or unrelated revisions of channels than those
4379 @cindex downgrade attacks, protection against
4380 By default, @command{guix pull} protects against so-called ``downgrade
4381 attacks'' whereby the Git repository of a channel would be reset to an
4382 earlier or unrelated revision of itself, potentially leading you to
4383 install older, known-vulnerable versions of software packages.
4386 Make sure you understand its security implications before using
4387 @option{--allow-downgrades}.
4390 @item --disable-authentication
4391 Allow pulling channel code without authenticating it.
4393 @cindex authentication, of channel code
4394 By default, @command{guix pull} authenticates code downloaded from
4395 channels by verifying that its commits are signed by authorized
4396 developers, and raises an error if this is not the case. This option
4397 instructs it to not perform any such verification.
4400 Make sure you understand its security implications before using
4401 @option{--disable-authentication}.
4404 @item --system=@var{system}
4405 @itemx -s @var{system}
4406 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4407 the system type of the build host.
4410 Use the bootstrap Guile to build the latest Guix. This option is only
4411 useful to Guix developers.
4414 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
4415 repository and branch to pull from, as well as @emph{additional} repositories
4416 containing package modules that should be deployed. @xref{Channels}, for more
4419 In addition, @command{guix pull} supports all the common build options
4420 (@pxref{Common Build Options}).
4422 @node Invoking guix time-machine
4423 @section Invoking @command{guix time-machine}
4425 @cindex @command{guix time-machine}
4426 @cindex pinning, channels
4427 @cindex replicating Guix
4428 @cindex reproducibility, of Guix
4430 The @command{guix time-machine} command provides access to other
4431 revisions of Guix, for example to install older versions of packages,
4432 or to reproduce a computation in an identical environment. The revision
4433 of Guix to be used is defined by a commit or by a channel
4434 description file created by @command{guix describe}
4435 (@pxref{Invoking guix describe}).
4437 The general syntax is:
4440 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4443 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4444 @command{guix} command of the specified revision. The @var{options} that define
4445 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4448 @item --url=@var{url}
4449 @itemx --commit=@var{commit}
4450 @itemx --branch=@var{branch}
4451 Use the @code{guix} channel from the specified @var{url}, at the
4452 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4453 string), or @var{branch}.
4455 @item --channels=@var{file}
4456 @itemx -C @var{file}
4457 Read the list of channels from @var{file}. @var{file} must contain
4458 Scheme code that evaluates to a list of channel objects.
4459 @xref{Channels} for more information.
4462 As for @command{guix pull}, the absence of any options means that the
4463 latest commit on the master branch will be used. The command
4466 guix time-machine -- build hello
4469 will thus build the package @code{hello} as defined in the master branch,
4470 which is in general a newer revision of Guix than you have installed.
4471 Time travel works in both directions!
4473 Note that @command{guix time-machine} can trigger builds of channels and
4474 their dependencies, and these are controlled by the standard build
4475 options (@pxref{Common Build Options}).
4480 @c TODO: Remove this once we're more confident about API stability.
4482 The functionality described here is a ``technology preview'' as of version
4483 @value{VERSION}. As such, the interface is subject to change.
4487 @cindex composition of Guix revisions
4488 Sometimes you might need to mix packages from the revision of Guix you're
4489 currently running with packages available in a different revision of Guix.
4490 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4491 revisions in arbitrary ways.
4493 @cindex inferior packages
4494 Technically, an ``inferior'' is essentially a separate Guix process connected
4495 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4496 @code{(guix inferior)} module allows you to create inferiors and to
4497 communicate with them. It also provides a high-level interface to browse and
4498 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4500 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4501 to interact with a separate revision of Guix. For example, let's assume you
4502 want to install in your profile the current @code{guile} package, along with
4503 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4504 because the newer @code{guile-json} has an incompatible API and you want to
4505 run your code against the old API@. To do that, you could write a manifest for
4506 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4507 manifest, you would create an inferior for that old Guix revision you care
4508 about, and you would look up the @code{guile-json} package in the inferior:
4511 (use-modules (guix inferior) (guix channels)
4512 (srfi srfi-1)) ;for 'first'
4515 ;; This is the old revision from which we want to
4516 ;; extract guile-json.
4519 (url "https://git.savannah.gnu.org/git/guix.git")
4521 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4524 ;; An inferior representing the above revision.
4525 (inferior-for-channels channels))
4527 ;; Now create a manifest with the current "guile" package
4528 ;; and the old "guile-json" package.
4530 (list (first (lookup-inferior-packages inferior "guile-json"))
4531 (specification->package "guile")))
4534 On its first run, @command{guix package --manifest} might have to build the
4535 channel you specified before it can create the inferior; subsequent runs will
4536 be much faster because the Guix revision will be cached.
4538 The @code{(guix inferior)} module provides the following procedures to open an
4541 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4542 [#:cache-directory] [#:ttl]
4543 Return an inferior for @var{channels}, a list of channels. Use the cache at
4544 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4545 This procedure opens a new connection to the build daemon.
4547 As a side effect, this procedure may build or substitute binaries for
4548 @var{channels}, which can take time.
4551 @deffn {Scheme Procedure} open-inferior @var{directory} @
4552 [#:command "bin/guix"]
4553 Open the inferior Guix in @var{directory}, running
4554 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4555 the inferior could not be launched.
4558 @cindex inferior packages
4559 The procedures listed below allow you to obtain and manipulate inferior
4562 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4563 Return the list of packages known to @var{inferior}.
4566 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4568 Return the sorted list of inferior packages matching @var{name} in
4569 @var{inferior}, with highest version numbers first. If @var{version} is true,
4570 return only packages with a version number prefixed by @var{version}.
4573 @deffn {Scheme Procedure} inferior-package? @var{obj}
4574 Return true if @var{obj} is an inferior package.
4577 @deffn {Scheme Procedure} inferior-package-name @var{package}
4578 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4579 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4580 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4581 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4582 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4583 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4584 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4585 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4586 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4587 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4588 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4589 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4590 These procedures are the counterpart of package record accessors
4591 (@pxref{package Reference}). Most of them work by querying the inferior
4592 @var{package} comes from, so the inferior must still be live when you call
4596 Inferior packages can be used transparently like any other package or
4597 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4598 transparently handled by the @code{packages->manifest} procedure, which is
4599 commonly use in manifests (@pxref{Invoking guix package, the
4600 @option{--manifest} option of @command{guix package}}). Thus you can insert
4601 an inferior package pretty much anywhere you would insert a regular package:
4602 in manifests, in the @code{packages} field of your @code{operating-system}
4603 declaration, and so on.
4605 @node Invoking guix describe
4606 @section Invoking @command{guix describe}
4608 @cindex reproducibility
4609 @cindex replicating Guix
4610 Often you may want to answer questions like: ``Which revision of Guix am I
4611 using?'' or ``Which channels am I using?'' This is useful information in many
4612 situations: if you want to @emph{replicate} an environment on a different
4613 machine or user account, if you want to report a bug or to determine what
4614 change in the channels you are using caused it, or if you want to record your
4615 system state for reproducibility purposes. The @command{guix describe}
4616 command answers these questions.
4618 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4619 displays the channel(s) that it was built from, including their repository URL
4620 and commit IDs (@pxref{Channels}):
4624 Generation 10 Sep 03 2018 17:32:44 (current)
4626 repository URL: https://git.savannah.gnu.org/git/guix.git
4628 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4631 If you're familiar with the Git version control system, this is similar in
4632 spirit to @command{git describe}; the output is also similar to that of
4633 @command{guix pull --list-generations}, but limited to the current generation
4634 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4635 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4636 information is all it takes to describe the revision of Guix you're using, and
4637 also to replicate it.
4639 To make it easier to replicate Guix, @command{guix describe} can also be asked
4640 to return a list of channels instead of the human-readable description above:
4643 $ guix describe -f channels
4646 (url "https://git.savannah.gnu.org/git/guix.git")
4648 "e0fa68c7718fffd33d81af415279d6ddb518f727")
4650 (make-channel-introduction
4651 "9edb3f66fd807b096b48283debdcddccfea34bad"
4652 (openpgp-fingerprint
4653 "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
4657 You can save this to a file and feed it to @command{guix pull -C} on some
4658 other machine or at a later point in time, which will instantiate @emph{this
4659 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4660 From there on, since you're able to deploy the same revision of Guix, you can
4661 just as well @emph{replicate a complete software environment}. We humbly
4662 think that this is @emph{awesome}, and we hope you'll like it too!
4664 The details of the options supported by @command{guix describe} are as
4668 @item --format=@var{format}
4669 @itemx -f @var{format}
4670 Produce output in the specified @var{format}, one of:
4674 produce human-readable output;
4676 produce a list of channel specifications that can be passed to @command{guix
4677 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4679 @item channels-sans-intro
4680 like @code{channels}, but omit the @code{introduction} field; use it to
4681 produce a channel specification suitable for Guix version 1.1.0 or
4682 earlier---the @code{introduction} field has to do with channel
4683 authentication (@pxref{Channels, Channel Authentication}) and is not
4684 supported by these older versions;
4687 produce a list of channel specifications in JSON format;
4689 produce a list of channel specifications in Recutils format.
4692 @item --list-formats
4693 Display available formats for @option{--format} option.
4695 @item --profile=@var{profile}
4696 @itemx -p @var{profile}
4697 Display information about @var{profile}.
4700 @node Invoking guix archive
4701 @section Invoking @command{guix archive}
4703 @cindex @command{guix archive}
4705 The @command{guix archive} command allows users to @dfn{export} files
4706 from the store into a single archive, and to later @dfn{import} them on
4707 a machine that runs Guix.
4708 In particular, it allows store files to be transferred from one machine
4709 to the store on another machine.
4712 If you're looking for a way to produce archives in a format suitable for
4713 tools other than Guix, @pxref{Invoking guix pack}.
4716 @cindex exporting store items
4717 To export store files as an archive to standard output, run:
4720 guix archive --export @var{options} @var{specifications}...
4723 @var{specifications} may be either store file names or package
4724 specifications, as for @command{guix package} (@pxref{Invoking guix
4725 package}). For instance, the following command creates an archive
4726 containing the @code{gui} output of the @code{git} package and the main
4727 output of @code{emacs}:
4730 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4733 If the specified packages are not built yet, @command{guix archive}
4734 automatically builds them. The build process may be controlled with the
4735 common build options (@pxref{Common Build Options}).
4737 To transfer the @code{emacs} package to a machine connected over SSH,
4741 guix archive --export -r emacs | ssh the-machine guix archive --import
4745 Similarly, a complete user profile may be transferred from one machine
4746 to another like this:
4749 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4750 ssh the-machine guix archive --import
4754 However, note that, in both examples, all of @code{emacs} and the
4755 profile as well as all of their dependencies are transferred (due to
4756 @option{-r}), regardless of what is already available in the store on
4757 the target machine. The @option{--missing} option can help figure out
4758 which items are missing from the target store. The @command{guix copy}
4759 command simplifies and optimizes this whole process, so this is probably
4760 what you should use in this case (@pxref{Invoking guix copy}).
4762 @cindex nar, archive format
4763 @cindex normalized archive (nar)
4764 @cindex nar bundle, archive format
4765 Each store item is written in the @dfn{normalized archive} or @dfn{nar}
4766 format (described below), and the output of @command{guix archive
4767 --export} (and input of @command{guix archive --import}) is a @dfn{nar
4771 comparable in spirit to `tar', but with differences
4772 that make it more appropriate for our purposes. First, rather than
4773 recording all Unix metadata for each file, the nar format only mentions
4774 the file type (regular, directory, or symbolic link); Unix permissions
4775 and owner/group are dismissed. Second, the order in which directory
4776 entries are stored always follows the order of file names according to
4777 the C locale collation order. This makes archive production fully
4780 That nar bundle format is essentially the concatenation of zero or more
4781 nars along with metadata for each store item it contains: its file name,
4782 references, corresponding derivation, and a digital signature.
4784 When exporting, the daemon digitally signs the contents of the archive,
4785 and that digital signature is appended. When importing, the daemon
4786 verifies the signature and rejects the import in case of an invalid
4787 signature or if the signing key is not authorized.
4788 @c FIXME: Add xref to daemon doc about signatures.
4790 The main options are:
4794 Export the specified store files or packages (see below). Write the
4795 resulting archive to the standard output.
4797 Dependencies are @emph{not} included in the output, unless
4798 @option{--recursive} is passed.
4802 When combined with @option{--export}, this instructs @command{guix archive}
4803 to include dependencies of the given items in the archive. Thus, the
4804 resulting archive is self-contained: it contains the closure of the
4805 exported store items.
4808 Read an archive from the standard input, and import the files listed
4809 therein into the store. Abort if the archive has an invalid digital
4810 signature, or if it is signed by a public key not among the authorized
4811 keys (see @option{--authorize} below).
4814 Read a list of store file names from the standard input, one per line,
4815 and write on the standard output the subset of these files missing from
4818 @item --generate-key[=@var{parameters}]
4819 @cindex signing, archives
4820 Generate a new key pair for the daemon. This is a prerequisite before
4821 archives can be exported with @option{--export}. This
4822 operation is usually instantaneous but it can take time if the system's
4823 entropy pool needs to be refilled. On Guix System,
4824 @code{guix-service-type} takes care of generating this key pair the
4827 The generated key pair is typically stored under @file{/etc/guix}, in
4828 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4829 key, which must be kept secret). When @var{parameters} is omitted,
4830 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4831 versions before 1.6.0, it is a 4096-bit RSA key.
4832 Alternatively, @var{parameters} can specify
4833 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4834 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4835 Libgcrypt Reference Manual}).
4838 @cindex authorizing, archives
4839 Authorize imports signed by the public key passed on standard input.
4840 The public key must be in ``s-expression advanced format''---i.e., the
4841 same format as the @file{signing-key.pub} file.
4843 The list of authorized keys is kept in the human-editable file
4844 @file{/etc/guix/acl}. The file contains
4845 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4846 s-expressions''} and is structured as an access-control list in the
4847 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4850 @item --extract=@var{directory}
4851 @itemx -x @var{directory}
4852 Read a single-item archive as served by substitute servers
4853 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4854 low-level operation needed in only very narrow use cases; see below.
4856 For example, the following command extracts the substitute for Emacs
4857 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4861 https://@value{SUBSTITUTE-SERVER}/nar/gzip/@dots{}-emacs-24.5 \
4862 | gunzip | guix archive -x /tmp/emacs
4865 Single-item archives are different from multiple-item archives produced
4866 by @command{guix archive --export}; they contain a single store item,
4867 and they do @emph{not} embed a signature. Thus this operation does
4868 @emph{no} signature verification and its output should be considered
4871 The primary purpose of this operation is to facilitate inspection of
4872 archive contents coming from possibly untrusted substitute servers
4873 (@pxref{Invoking guix challenge}).
4877 Read a single-item archive as served by substitute servers
4878 (@pxref{Substitutes}) and print the list of files it contains, as in
4883 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4884 | lzip -d | guix archive -t
4889 @c *********************************************************************
4894 @cindex @file{channels.scm}, configuration file
4895 @cindex configuration file for channels
4896 @cindex @command{guix pull}, configuration file
4897 @cindex configuration of @command{guix pull}
4898 Guix and its package collection are updated by running @command{guix pull}
4899 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
4900 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
4901 customized by defining @dfn{channels} in the
4902 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
4903 of a Git repository to be deployed, and @command{guix pull} can be instructed
4904 to pull from one or more channels. In other words, channels can be used
4905 to @emph{customize} and to @emph{extend} Guix, as we will see below.
4906 Guix is able to take into account security concerns and deal with authenticated
4910 * Specifying Additional Channels:: Extending the package collection.
4911 * Using a Custom Guix Channel:: Using a customized Guix.
4912 * Replicating Guix:: Running the @emph{exact same} Guix.
4913 * Channel Authentication:: How Guix verifies what it fetches.
4914 * Creating a Channel:: How to write your custom channel.
4915 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
4916 * Declaring Channel Dependencies:: How to depend on other channels.
4917 * Specifying Channel Authorizations:: Defining channel authors authorizations.
4918 * Primary URL:: Distinguishing mirror to original.
4919 * Writing Channel News:: Communicating information to channel's users.
4922 @node Specifying Additional Channels
4923 @section Specifying Additional Channels
4925 @cindex extending the package collection (channels)
4926 @cindex variant packages (channels)
4927 You can specify @emph{additional channels} to pull from. To use a channel, write
4928 @code{~/.config/guix/channels.scm} to instruct @command{guix pull} to pull from it
4929 @emph{in addition} to the default Guix channel(s):
4931 @vindex %default-channels
4933 ;; Add variant packages to those Guix provides.
4935 (name 'variant-packages)
4936 (url "https://example.org/variant-packages.git"))
4941 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
4942 add a channel the list of channels that the variable @code{%default-channels}
4943 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
4944 Manual}). With this file in place, @command{guix pull} builds not only Guix
4945 but also the package modules from your own repository. The result in
4946 @file{~/.config/guix/current} is the union of Guix with your own package
4950 $ guix pull --list-generations
4952 Generation 19 Aug 27 2018 16:20:48
4954 repository URL: https://git.savannah.gnu.org/git/guix.git
4956 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
4957 variant-packages dd3df5e
4958 repository URL: https://example.org/variant-packages.git
4960 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
4961 11 new packages: variant-gimp, variant-emacs-with-cool-features, @dots{}
4962 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
4966 The output of @command{guix pull} above shows that Generation@tie{}19 includes
4967 both Guix and packages from the @code{variant-personal-packages} channel. Among
4968 the new and upgraded packages that are listed, some like @code{variant-gimp} and
4969 @code{variant-emacs-with-cool-features} might come from
4970 @code{variant-packages}, while others come from the Guix default channel.
4972 @node Using a Custom Guix Channel
4973 @section Using a Custom Guix Channel
4975 The channel called @code{guix} specifies where Guix itself---its command-line
4976 tools as well as its package collection---should be downloaded. For instance,
4977 suppose you want to update from another copy of the Guix repository at
4978 @code{example.org}, and specifically the @code{super-hacks} branch, you can
4979 write in @code{~/.config/guix/channels.scm} this specification:
4982 ;; Tell 'guix pull' to use another repo.
4985 (url "https://example.org/another-guix.git")
4986 (branch "super-hacks")))
4990 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
4991 branch of the repository at @code{example.org}. The authentication concern is
4992 addressed below ((@pxref{Channel Authentication}).
4994 @node Replicating Guix
4995 @section Replicating Guix
4997 @cindex pinning, channels
4998 @cindex replicating Guix
4999 @cindex reproducibility, of Guix
5000 The @command{guix pull --list-generations} output above shows precisely which
5001 commits were used to build this instance of Guix. We can thus replicate it,
5002 say, on another machine, by providing a channel specification in
5003 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
5006 ;; Deploy specific commits of my channels of interest.
5009 (url "https://git.savannah.gnu.org/git/guix.git")
5010 (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
5012 (name 'variant-packages)
5013 (url "https://example.org/variant-packages.git")
5014 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
5017 The @command{guix describe --format=channels} command can even generate this
5018 list of channels directly (@pxref{Invoking guix describe}). The resulting
5019 file can be used with the -C options of @command{guix pull}
5020 (@pxref{Invoking guix pull}) or @command{guix time-machine}
5021 (@pxref{Invoking guix time-machine}).
5023 At this point the two machines run the @emph{exact same Guix}, with access to
5024 the @emph{exact same packages}. The output of @command{guix build gimp} on
5025 one machine will be exactly the same, bit for bit, as the output of the same
5026 command on the other machine. It also means both machines have access to all
5027 the source code of Guix and, transitively, to all the source code of every
5030 This gives you super powers, allowing you to track the provenance of binary
5031 artifacts with very fine grain, and to reproduce software environments at
5032 will---some sort of ``meta reproducibility'' capabilities, if you will.
5033 @xref{Inferiors}, for another way to take advantage of these super powers.
5035 @node Channel Authentication
5036 @section Channel Authentication
5038 @anchor{channel-authentication}
5039 @cindex authentication, of channel code
5040 The @command{guix pull} and @command{guix time-machine} commands
5041 @dfn{authenticate} the code retrieved from channels: they make sure each
5042 commit that is fetched is signed by an authorized developer. The goal
5043 is to protect from unauthorized modifications to the channel that would
5044 lead users to run malicious code.
5046 As a user, you must provide a @dfn{channel introduction} in your
5047 channels file so that Guix knows how to authenticate its first commit.
5048 A channel specification, including its introduction, looks something
5053 (name 'some-channel)
5054 (url "https://example.org/some-channel.git")
5056 (make-channel-introduction
5057 "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
5058 (openpgp-fingerprint
5059 "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5062 The specification above shows the name and URL of the channel. The call
5063 to @code{make-channel-introduction} above specifies that authentication
5064 of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
5065 by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
5067 For the main channel, called @code{guix}, you automatically get that
5068 information from your Guix installation. For other channels, include
5069 the channel introduction provided by the channel authors in your
5070 @file{channels.scm} file. Make sure you retrieve the channel
5071 introduction from a trusted source since that is the root of your trust.
5073 If you're curious about the authentication mechanics, read on!
5075 @node Creating a Channel
5076 @section Creating a Channel
5078 @cindex personal packages (channels)
5079 @cindex channels, for personal packages
5080 Let's say you have a bunch of custom package variants or personal packages
5081 that you think would make little sense to contribute to the Guix project, but
5082 would like to have these packages transparently available to you at the
5083 command line. You would first write modules containing those package
5084 definitions (@pxref{Package Modules}), maintain them in a Git repository, and
5085 then you and anyone else can use it as an additional channel to get packages
5088 @c What follows stems from discussions at
5089 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
5090 @c earlier discussions on guix-devel@gnu.org.
5092 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
5093 publish your personal channel to the world, we would like to share a few words
5098 Before publishing a channel, please consider contributing your package
5099 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
5100 to free software of all sorts, and packages in Guix proper are readily
5101 available to all Guix users and benefit from the project's quality assurance
5105 When you maintain package definitions outside Guix, we, Guix developers,
5106 consider that @emph{the compatibility burden is on you}. Remember that
5107 package modules and package definitions are just Scheme code that uses various
5108 programming interfaces (APIs). We want to remain free to change these APIs to
5109 keep improving Guix, possibly in ways that break your channel. We never
5110 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
5114 Corollary: if you're using an external channel and that channel breaks, please
5115 @emph{report the issue to the channel authors}, not to the Guix project.
5118 You've been warned! Having said this, we believe external channels are a
5119 practical way to exert your freedom to augment Guix' package collection and to
5120 share your improvements, which are basic tenets of
5121 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
5122 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
5125 To create a channel, create a Git repository containing your own package
5126 modules and make it available. The repository can contain anything, but a
5127 useful channel will contain Guile modules that export packages. Once you
5128 start using a channel, Guix will behave as if the root directory of that
5129 channel's Git repository has been added to the Guile load path (@pxref{Load
5130 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
5131 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
5132 module, then the module will be available under the name @code{(my-packages
5133 my-tools)}, and you will be able to use it like any other module
5134 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
5136 As a channel author, consider bundling authentication material with your
5137 channel so that users can authenticate it. @xref{Channel
5138 Authentication}, and @ref{Specifying Channel Authorizations}, for info
5142 @node Package Modules in a Sub-directory
5143 @section Package Modules in a Sub-directory
5145 @cindex subdirectory, channels
5146 As a channel author, you may want to keep your channel modules in a
5147 sub-directory. If your modules are in the sub-directory @file{guix}, you must
5148 add a meta-data file @file{.guix-channel} that contains:
5156 @node Declaring Channel Dependencies
5157 @section Declaring Channel Dependencies
5159 @cindex dependencies, channels
5160 @cindex meta-data, channels
5161 Channel authors may decide to augment a package collection provided by other
5162 channels. They can declare their channel to be dependent on other channels in
5163 a meta-data file @file{.guix-channel}, which is to be placed in the root of
5164 the channel repository.
5166 The meta-data file should contain a simple S-expression like this:
5173 (name 'some-collection)
5174 (url "https://example.org/first-collection.git")
5176 ;; The 'introduction' bit below is optional: you would
5177 ;; provide it for dependencies that can be authenticated.
5179 (channel-introduction
5181 (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
5182 (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5184 (name 'some-other-collection)
5185 (url "https://example.org/second-collection.git")
5186 (branch "testing"))))
5189 In the above example this channel is declared to depend on two other channels,
5190 which will both be fetched automatically. The modules provided by the channel
5191 will be compiled in an environment where the modules of all these declared
5192 channels are available.
5194 For the sake of reliability and maintainability, you should avoid dependencies
5195 on channels that you don't control, and you should aim to keep the number of
5196 dependencies to a minimum.
5198 @node Specifying Channel Authorizations
5199 @section Specifying Channel Authorizations
5201 @cindex channel authorizations
5202 @anchor{channel-authorizations}
5203 As we saw above, Guix ensures the source code it pulls from channels
5204 comes from authorized developers. As a channel author, you need to
5205 specify the list of authorized developers in the
5206 @file{.guix-authorizations} file in the channel's Git repository. The
5207 authentication rule is simple: each commit must be signed by a key
5208 listed in the @file{.guix-authorizations} file of its parent
5209 commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
5210 (DAG). Each commit can have zero or more parents; ``regular'' commits
5211 have one parent and merge commits have two parent commits. Read
5212 @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
5213 for Computer Scientists}} for a great overview.} The
5214 @file{.guix-authorizations} file looks like this:
5217 ;; Example '.guix-authorizations' file.
5220 (version 0) ;current file format version
5222 (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
5224 ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
5226 ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
5230 Each fingerprint is followed by optional key/value pairs, as in the
5231 example above. Currently these key/value pairs are ignored.
5233 This authentication rule creates a chicken-and-egg issue: how do we
5234 authenticate the first commit? Related to that: how do we deal with
5235 channels whose repository history contains unsigned commits and lack
5236 @file{.guix-authorizations}? And how do we fork existing channels?
5238 @cindex channel introduction
5239 Channel introductions answer these questions by describing the first
5240 commit of a channel that should be authenticated. The first time a
5241 channel is fetched with @command{guix pull} or @command{guix
5242 time-machine}, the command looks up the introductory commit and verifies
5243 that it is signed by the specified OpenPGP key. From then on, it
5244 authenticates commits according to the rule above.
5246 Additionally, your channel must provide all the OpenPGP keys that were
5247 ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
5248 files, which can be either binary or ``ASCII-armored''. By default,
5249 those @file{.key} files are searched for in the branch named
5250 @code{keyring} but you can specify a different branch name in
5251 @code{.guix-channel} like so:
5256 (keyring-reference "my-keyring-branch"))
5259 To summarize, as the author of a channel, there are three things you have
5260 to do to allow users to authenticate your code:
5264 Export the OpenPGP keys of past and present committers with @command{gpg
5265 --export} and store them in @file{.key} files, by default in a branch
5266 named @code{keyring} (we recommend making it an @dfn{orphan branch}).
5269 Introduce an initial @file{.guix-authorizations} in the channel's
5270 repository. Do that in a signed commit (@pxref{Commit Access}, for
5271 information on how to sign Git commits.)
5274 Advertise the channel introduction, for instance on your channel's web
5275 page. The channel introduction, as we saw above, is the commit/key
5276 pair---i.e., the commit that introduced @file{.guix-authorizations}, and
5277 the fingerprint of the OpenPGP used to sign it.
5280 Before pushing to your public Git repository, you can run @command{guix
5281 git-authenticate} to verify that you did sign all the commits you are
5282 about to push with an authorized key:
5285 guix git authenticate @var{commit} @var{signer}
5289 where @var{commit} and @var{signer} are your channel introduction.
5290 @xref{Invoking guix git authenticate}, for details.
5292 Publishing a signed channel requires discipline: any mistake, such as an
5293 unsigned commit or a commit signed by an unauthorized key, will prevent
5294 users from pulling from your channel---well, that's the whole point of
5295 authentication! Pay attention to merges in particular: merge commits
5296 are considered authentic if and only if they are signed by a key present
5297 in the @file{.guix-authorizations} file of @emph{both} branches.
5300 @section Primary URL
5302 @cindex primary URL, channels
5303 Channel authors can indicate the primary URL of their channel's Git
5304 repository in the @file{.guix-channel} file, like so:
5309 (url "https://example.org/guix.git"))
5312 This allows @command{guix pull} to determine whether it is pulling code
5313 from a mirror of the channel; when that is the case, it warns the user
5314 that the mirror might be stale and displays the primary URL. That way,
5315 users cannot be tricked into fetching code from a stale mirror that does
5316 not receive security updates.
5318 This feature only makes sense for authenticated repositories, such as
5319 the official @code{guix} channel, for which @command{guix pull} ensures
5320 the code it fetches is authentic.
5322 @node Writing Channel News
5323 @section Writing Channel News
5325 @cindex news, for channels
5326 Channel authors may occasionally want to communicate to their users
5327 information about important changes in the channel. You'd send them all
5328 an email, but that's not convenient.
5330 Instead, channels can provide a @dfn{news file}; when the channel users
5331 run @command{guix pull}, that news file is automatically read and
5332 @command{guix pull --news} can display the announcements that correspond
5333 to the new commits that have been pulled, if any.
5335 To do that, channel authors must first declare the name of the news file
5336 in their @file{.guix-channel} file:
5341 (news-file "etc/news.txt"))
5344 The news file itself, @file{etc/news.txt} in this example, must look
5345 something like this:
5350 (entry (tag "the-bug-fix")
5351 (title (en "Fixed terrible bug")
5353 (body (en "@@emph@{Good news@}! It's fixed!")
5354 (eo "Certe ĝi pli bone funkcias nun!")))
5355 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
5356 (title (en "Added a great package")
5357 (ca "Què vol dir guix?"))
5358 (body (en "Don't miss the @@code@{hello@} package!"))))
5361 While the news file is using the Scheme syntax, avoid naming it with a
5362 @file{.scm} extension or else it will get picked up when building the
5363 channel and yield an error since it is not a valid module.
5364 Alternatively, you can move the channel module to a subdirectory and
5365 store the news file in another directory.
5367 The file consists of a list of @dfn{news entries}. Each entry is
5368 associated with a commit or tag: it describes changes made in this
5369 commit, possibly in preceding commits as well. Users see entries only
5370 the first time they obtain the commit the entry refers to.
5372 The @code{title} field should be a one-line summary while @code{body}
5373 can be arbitrarily long, and both can contain Texinfo markup
5374 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
5375 a list of language tag/message tuples, which allows @command{guix pull}
5376 to display news in the language that corresponds to the user's locale.
5378 If you want to translate news using a gettext-based workflow, you can
5379 extract translatable strings with @command{xgettext} (@pxref{xgettext
5380 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
5381 you write news entries in English first, the command below creates a PO
5382 file containing the strings to translate:
5385 xgettext -o news.po -l scheme -ken etc/news.txt
5388 To sum up, yes, you could use your channel as a blog. But beware, this
5389 is @emph{not quite} what your users might expect.
5392 @c *********************************************************************
5394 @chapter Development
5396 @cindex software development
5397 If you are a software developer, Guix provides tools that you should find
5398 helpful---independently of the language you're developing in. This is what
5399 this chapter is about.
5401 The @command{guix environment} command provides a convenient way to set up
5402 @dfn{development environments} containing all the dependencies and tools
5403 necessary to work on the software package of your choice. The @command{guix
5404 pack} command allows you to create @dfn{application bundles} that can be
5405 easily distributed to users who do not run Guix.
5408 * Invoking guix environment:: Setting up development environments.
5409 * Invoking guix pack:: Creating software bundles.
5410 * The GCC toolchain:: Working with languages supported by GCC.
5411 * Invoking guix git authenticate:: Authenticating Git repositories.
5414 @node Invoking guix environment
5415 @section Invoking @command{guix environment}
5417 @cindex reproducible build environments
5418 @cindex development environments
5419 @cindex @command{guix environment}
5420 @cindex environment, package build environment
5421 The purpose of @command{guix environment} is to assist hackers in
5422 creating reproducible development environments without polluting their
5423 package profile. The @command{guix environment} tool takes one or more
5424 packages, builds all of their inputs, and creates a shell
5425 environment to use them.
5427 The general syntax is:
5430 guix environment @var{options} @var{package}@dots{}
5433 The following example spawns a new shell set up for the development of
5437 guix environment guile
5440 If the needed dependencies are not built yet, @command{guix environment}
5441 automatically builds them. The environment of the new shell is an
5442 augmented version of the environment that @command{guix environment} was
5443 run in. It contains the necessary search paths for building the given
5444 package added to the existing environment variables. To create
5445 a ``pure'' environment, in which the original environment variables have
5446 been unset, use the @option{--pure} option@footnote{Users sometimes
5447 wrongfully augment environment variables such as @env{PATH} in their
5448 @file{~/.bashrc} file. As a consequence, when @command{guix
5449 environment} launches it, Bash may read @file{~/.bashrc}, thereby
5450 introducing ``impurities'' in these environment variables. It is an
5451 error to define such environment variables in @file{.bashrc}; instead,
5452 they should be defined in @file{.bash_profile}, which is sourced only by
5453 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
5454 Manual}, for details on Bash start-up files.}.
5456 @vindex GUIX_ENVIRONMENT
5457 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
5458 variable in the shell it spawns; its value is the file name of the
5459 profile of this environment. This allows users to, say, define a
5460 specific prompt for development environments in their @file{.bashrc}
5461 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
5464 if [ -n "$GUIX_ENVIRONMENT" ]
5466 export PS1="\u@@\h \w [dev]\$ "
5471 ...@: or to browse the profile:
5474 $ ls "$GUIX_ENVIRONMENT/bin"
5477 Additionally, more than one package may be specified, in which case the
5478 union of the inputs for the given packages are used. For example, the
5479 command below spawns a shell where all of the dependencies of both Guile
5480 and Emacs are available:
5483 guix environment guile emacs
5486 Sometimes an interactive shell session is not desired. An arbitrary
5487 command may be invoked by placing the @code{--} token to separate the
5488 command from the rest of the arguments:
5491 guix environment guile -- make -j4
5494 In other situations, it is more convenient to specify the list of
5495 packages needed in the environment. For example, the following command
5496 runs @command{python} from an environment containing Python@tie{}2.7 and
5500 guix environment --ad-hoc python2-numpy python-2.7 -- python
5503 Furthermore, one might want the dependencies of a package and also some
5504 additional packages that are not build-time or runtime dependencies, but
5505 are useful when developing nonetheless. Because of this, the
5506 @option{--ad-hoc} flag is positional. Packages appearing before
5507 @option{--ad-hoc} are interpreted as packages whose dependencies will be
5508 added to the environment. Packages appearing after are interpreted as
5509 packages that will be added to the environment directly. For example,
5510 the following command creates a Guix development environment that
5511 additionally includes Git and strace:
5514 guix environment --pure guix --ad-hoc git strace
5518 Sometimes it is desirable to isolate the environment as much as
5519 possible, for maximal purity and reproducibility. In particular, when
5520 using Guix on a host distro that is not Guix System, it is desirable to
5521 prevent access to @file{/usr/bin} and other system-wide resources from
5522 the development environment. For example, the following command spawns
5523 a Guile REPL in a ``container'' where only the store and the current
5524 working directory are mounted:
5527 guix environment --ad-hoc --container guile -- guile
5531 The @option{--container} option requires Linux-libre 3.19 or newer.
5534 @cindex certificates
5535 Another typical use case for containers is to run security-sensitive
5536 applications such as a web browser. To run Eolie, we must expose and
5537 share some files and directories; we include @code{nss-certs} and expose
5538 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
5539 @env{DISPLAY} environment variable since containerized graphical
5540 applications won't display without it.
5543 guix environment --preserve='^DISPLAY$' --container --network \
5544 --expose=/etc/machine-id \
5545 --expose=/etc/ssl/certs/ \
5546 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
5547 --ad-hoc eolie nss-certs dbus -- eolie
5550 The available options are summarized below.
5553 @item --root=@var{file}
5554 @itemx -r @var{file}
5555 @cindex persistent environment
5556 @cindex garbage collector root, for environments
5557 Make @var{file} a symlink to the profile for this environment, and
5558 register it as a garbage collector root.
5560 This is useful if you want to protect your environment from garbage
5561 collection, to make it ``persistent''.
5563 When this option is omitted, the environment is protected from garbage
5564 collection only for the duration of the @command{guix environment}
5565 session. This means that next time you recreate the same environment,
5566 you could have to rebuild or re-download packages. @xref{Invoking guix
5567 gc}, for more on GC roots.
5569 @item --expression=@var{expr}
5570 @itemx -e @var{expr}
5571 Create an environment for the package or list of packages that
5572 @var{expr} evaluates to.
5574 For example, running:
5577 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
5580 starts a shell with the environment for this specific variant of the
5586 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
5589 starts a shell with all the base system packages available.
5591 The above commands only use the default output of the given packages.
5592 To select other outputs, two element tuples can be specified:
5595 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
5598 @item --load=@var{file}
5599 @itemx -l @var{file}
5600 Create an environment for the package or list of packages that the code
5601 within @var{file} evaluates to.
5603 As an example, @var{file} might contain a definition like this
5604 (@pxref{Defining Packages}):
5607 @verbatiminclude environment-gdb.scm
5610 @item --manifest=@var{file}
5611 @itemx -m @var{file}
5612 Create an environment for the packages contained in the manifest object
5613 returned by the Scheme code in @var{file}. This option can be repeated
5614 several times, in which case the manifests are concatenated.
5616 This is similar to the same-named option in @command{guix package}
5617 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
5621 Include all specified packages in the resulting environment, as if an
5622 @i{ad hoc} package were defined with them as inputs. This option is
5623 useful for quickly creating an environment without having to write a
5624 package expression to contain the desired inputs.
5626 For instance, the command:
5629 guix environment --ad-hoc guile guile-sdl -- guile
5632 runs @command{guile} in an environment where Guile and Guile-SDL are
5635 Note that this example implicitly asks for the default output of
5636 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
5637 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
5638 of @code{glib} (@pxref{Packages with Multiple Outputs}).
5640 This option may be composed with the default behavior of @command{guix
5641 environment}. Packages appearing before @option{--ad-hoc} are
5642 interpreted as packages whose dependencies will be added to the
5643 environment, the default behavior. Packages appearing after are
5644 interpreted as packages that will be added to the environment directly.
5647 Unset existing environment variables when building the new environment, except
5648 those specified with @option{--preserve} (see below). This has the effect of
5649 creating an environment in which search paths only contain package inputs.
5651 @item --preserve=@var{regexp}
5652 @itemx -E @var{regexp}
5653 When used alongside @option{--pure}, preserve the environment variables
5654 matching @var{regexp}---in other words, put them on a ``white list'' of
5655 environment variables that must be preserved. This option can be repeated
5659 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
5663 This example runs @command{mpirun} in a context where the only environment
5664 variables defined are @env{PATH}, environment variables whose name starts
5665 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
5668 @item --search-paths
5669 Display the environment variable definitions that make up the
5672 @item --system=@var{system}
5673 @itemx -s @var{system}
5674 Attempt to build for @var{system}---e.g., @code{i686-linux}.
5679 Run @var{command} within an isolated container. The current working
5680 directory outside the container is mapped inside the container.
5681 Additionally, unless overridden with @option{--user}, a dummy home
5682 directory is created that matches the current user's home directory, and
5683 @file{/etc/passwd} is configured accordingly.
5685 The spawned process runs as the current user outside the container. Inside
5686 the container, it has the same UID and GID as the current user, unless
5687 @option{--user} is passed (see below).
5691 For containers, share the network namespace with the host system.
5692 Containers created without this flag only have access to the loopback
5695 @item --link-profile
5697 For containers, link the environment profile to @file{~/.guix-profile}
5698 within the container and set @code{GUIX_ENVIRONMENT} to that.
5699 This is equivalent to making @file{~/.guix-profile} a symlink to the
5700 actual profile within the container.
5701 Linking will fail and abort the environment if the directory already
5702 exists, which will certainly be the case if @command{guix environment}
5703 was invoked in the user's home directory.
5705 Certain packages are configured to look in @file{~/.guix-profile} for
5706 configuration files and data;@footnote{For example, the
5707 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
5708 for additional fonts.} @option{--link-profile} allows these programs to
5709 behave as expected within the environment.
5711 @item --user=@var{user}
5712 @itemx -u @var{user}
5713 For containers, use the username @var{user} in place of the current
5714 user. The generated @file{/etc/passwd} entry within the container will
5715 contain the name @var{user}, the home directory will be
5716 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
5717 the UID and GID inside the container are 1000. @var{user}
5718 need not exist on the system.
5720 Additionally, any shared or exposed path (see @option{--share} and
5721 @option{--expose} respectively) whose target is within the current user's
5722 home directory will be remapped relative to @file{/home/USER}; this
5723 includes the automatic mapping of the current working directory.
5726 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
5728 guix environment --container --user=foo \
5729 --expose=$HOME/test \
5730 --expose=/tmp/target=$HOME/target
5733 While this will limit the leaking of user identity through home paths
5734 and each of the user fields, this is only one useful component of a
5735 broader privacy/anonymity solution---not one in and of itself.
5738 For containers, the default behavior is to share the current working
5739 directory with the isolated container and immediately change to that
5740 directory within the container. If this is undesirable,
5741 @option{--no-cwd} will cause the current working directory to @emph{not}
5742 be automatically shared and will change to the user's home directory
5743 within the container instead. See also @option{--user}.
5745 @item --expose=@var{source}[=@var{target}]
5746 @itemx --share=@var{source}[=@var{target}]
5747 For containers, @option{--expose} (resp. @option{--share}) exposes the
5748 file system @var{source} from the host system as the read-only
5749 (resp. writable) file system @var{target} within the container. If
5750 @var{target} is not specified, @var{source} is used as the target mount
5751 point in the container.
5753 The example below spawns a Guile REPL in a container in which the user's
5754 home directory is accessible read-only via the @file{/exchange}
5758 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
5763 @command{guix environment}
5764 also supports all of the common build options that @command{guix
5765 build} supports (@pxref{Common Build Options}) as well as package
5766 transformation options (@pxref{Package Transformation Options}).
5768 @node Invoking guix pack
5769 @section Invoking @command{guix pack}
5771 Occasionally you want to pass software to people who are not (yet!)
5772 lucky enough to be using Guix. You'd tell them to run @command{guix
5773 package -i @var{something}}, but that's not possible in this case. This
5774 is where @command{guix pack} comes in.
5777 If you are looking for ways to exchange binaries among machines that
5778 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5779 publish}, and @ref{Invoking guix archive}.
5784 @cindex application bundle
5785 @cindex software bundle
5786 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5787 @dfn{software bundle}: it creates a tarball or some other archive
5788 containing the binaries of the software you're interested in, and all
5789 its dependencies. The resulting archive can be used on any machine that
5790 does not have Guix, and people can run the exact same binaries as those
5791 you have with Guix. The pack itself is created in a bit-reproducible
5792 fashion, so anyone can verify that it really contains the build results
5793 that you pretend to be shipping.
5795 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5796 their dependencies, you can run:
5799 $ guix pack guile emacs geiser
5801 /gnu/store/@dots{}-pack.tar.gz
5804 The result here is a tarball containing a @file{/gnu/store} directory
5805 with all the relevant packages. The resulting tarball contains a
5806 @dfn{profile} with the three packages of interest; the profile is the
5807 same as would be created by @command{guix package -i}. It is this
5808 mechanism that is used to create Guix's own standalone binary tarball
5809 (@pxref{Binary Installation}).
5811 Users of this pack would have to run
5812 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5813 find inconvenient. To work around it, you can create, say, a
5814 @file{/opt/gnu/bin} symlink to the profile:
5817 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5821 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5823 @cindex relocatable binaries, with @command{guix pack}
5824 What if the recipient of your pack does not have root privileges on
5825 their machine, and thus cannot unpack it in the root file system? In
5826 that case, you will want to use the @option{--relocatable} option (see
5827 below). This option produces @dfn{relocatable binaries}, meaning they
5828 they can be placed anywhere in the file system hierarchy: in the example
5829 above, users can unpack your tarball in their home directory and
5830 directly run @file{./opt/gnu/bin/guile}.
5832 @cindex Docker, build an image with guix pack
5833 Alternatively, you can produce a pack in the Docker image format using
5834 the following command:
5837 guix pack -f docker -S /bin=bin guile guile-readline
5841 The result is a tarball that can be passed to the @command{docker load}
5842 command, followed by @code{docker run}:
5845 docker load < @var{file}
5846 docker run -ti guile-guile-readline /bin/guile
5850 where @var{file} is the image returned by @var{guix pack}, and
5851 @code{guile-guile-readline} is its ``image tag''. See the
5852 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5853 documentation} for more information.
5855 @cindex Singularity, build an image with guix pack
5856 @cindex SquashFS, build an image with guix pack
5857 Yet another option is to produce a SquashFS image with the following
5861 guix pack -f squashfs bash guile emacs geiser
5865 The result is a SquashFS file system image that can either be mounted or
5866 directly be used as a file system container image with the
5867 @uref{https://www.sylabs.io/docs/, Singularity container execution
5868 environment}, using commands like @command{singularity shell} or
5869 @command{singularity exec}.
5871 Several command-line options allow you to customize your pack:
5874 @item --format=@var{format}
5875 @itemx -f @var{format}
5876 Produce a pack in the given @var{format}.
5878 The available formats are:
5882 This is the default format. It produces a tarball containing all the
5883 specified binaries and symlinks.
5886 This produces a tarball that follows the
5887 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
5888 Docker Image Specification}. The ``repository name'' as it appears in
5889 the output of the @command{docker images} command is computed from
5890 package names passed on the command line or in the manifest file.
5893 This produces a SquashFS image containing all the specified binaries and
5894 symlinks, as well as empty mount points for virtual file systems like
5898 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
5899 For that reason, @command{guix pack -f squashfs} always implies @code{-S
5900 /bin=bin}. Thus, your @command{guix pack} invocation must always start
5901 with something like:
5904 guix pack -f squashfs bash @dots{}
5907 If you forget the @code{bash} (or similar) package, @command{singularity
5908 run} and @command{singularity exec} will fail with an unhelpful ``no
5909 such file or directory'' message.
5913 @cindex relocatable binaries
5916 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
5917 anywhere in the file system hierarchy and run from there.
5919 When this option is passed once, the resulting binaries require support for
5920 @dfn{user namespaces} in the kernel Linux; when passed
5921 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
5922 PRoot support, can be thought of as the abbreviation of ``Really
5923 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
5924 other techniques if user namespaces are unavailable, and essentially
5925 work anywhere---see below for the implications.
5927 For example, if you create a pack containing Bash with:
5930 guix pack -RR -S /mybin=bin bash
5934 ...@: you can copy that pack to a machine that lacks Guix, and from your
5935 home directory as a normal user, run:
5943 In that shell, if you type @code{ls /gnu/store}, you'll notice that
5944 @file{/gnu/store} shows up and contains all the dependencies of
5945 @code{bash}, even though the machine actually lacks @file{/gnu/store}
5946 altogether! That is probably the simplest way to deploy Guix-built
5947 software on a non-Guix machine.
5950 By default, relocatable binaries rely on the @dfn{user namespace} feature of
5951 the kernel Linux, which allows unprivileged users to mount or change root.
5952 Old versions of Linux did not support it, and some GNU/Linux distributions
5955 To produce relocatable binaries that work even in the absence of user
5956 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
5957 case, binaries will try user namespace support and fall back to another
5958 @dfn{execution engine} if user namespaces are not supported. The
5959 following execution engines are supported:
5963 Try user namespaces and fall back to PRoot if user namespaces are not
5964 supported (see below).
5967 Try user namespaces and fall back to Fakechroot if user namespaces are
5968 not supported (see below).
5971 Run the program through user namespaces and abort if they are not
5975 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
5976 provides the necessary
5977 support for file system virtualization. It achieves that by using the
5978 @code{ptrace} system call on the running program. This approach has the
5979 advantage to work without requiring special kernel support, but it incurs
5980 run-time overhead every time a system call is made.
5983 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
5984 Fakechroot} virtualizes file system accesses by intercepting calls to C
5985 library functions such as @code{open}, @code{stat}, @code{exec}, and so
5986 on. Unlike PRoot, it incurs very little overhead. However, it does not
5987 always work: for example, some file system accesses made from within the
5988 C library are not intercepted, and file system accesses made @i{via}
5989 direct syscalls are not intercepted either, leading to erratic behavior.
5992 @vindex GUIX_EXECUTION_ENGINE
5993 When running a wrapped program, you can explicitly request one of the
5994 execution engines listed above by setting the
5995 @env{GUIX_EXECUTION_ENGINE} environment variable accordingly.
5998 @cindex entry point, for Docker images
5999 @item --entry-point=@var{command}
6000 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
6001 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
6002 support it. @var{command} must be relative to the profile contained in the
6005 The entry point specifies the command that tools like @code{docker run} or
6006 @code{singularity run} automatically start by default. For example, you can
6010 guix pack -f docker --entry-point=bin/guile guile
6013 The resulting pack can easily be loaded and @code{docker run} with no extra
6014 arguments will spawn @code{bin/guile}:
6017 docker load -i pack.tar.gz
6018 docker run @var{image-id}
6021 @item --expression=@var{expr}
6022 @itemx -e @var{expr}
6023 Consider the package @var{expr} evaluates to.
6025 This has the same purpose as the same-named option in @command{guix
6026 build} (@pxref{Additional Build Options, @option{--expression} in
6027 @command{guix build}}).
6029 @item --manifest=@var{file}
6030 @itemx -m @var{file}
6031 Use the packages contained in the manifest object returned by the Scheme
6032 code in @var{file}. This option can be repeated several times, in which
6033 case the manifests are concatenated.
6035 This has a similar purpose as the same-named option in @command{guix
6036 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
6037 same manifest files. It allows you to define a collection of packages
6038 once and use it both for creating profiles and for creating archives
6039 for use on machines that do not have Guix installed. Note that you can
6040 specify @emph{either} a manifest file @emph{or} a list of packages,
6043 @item --system=@var{system}
6044 @itemx -s @var{system}
6045 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
6046 the system type of the build host.
6048 @item --target=@var{triplet}
6049 @cindex cross-compilation
6050 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
6051 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
6052 configuration triplets,, autoconf, Autoconf}).
6054 @item --compression=@var{tool}
6055 @itemx -C @var{tool}
6056 Compress the resulting tarball using @var{tool}---one of @code{gzip},
6057 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
6060 @item --symlink=@var{spec}
6061 @itemx -S @var{spec}
6062 Add the symlinks specified by @var{spec} to the pack. This option can
6063 appear several times.
6065 @var{spec} has the form @code{@var{source}=@var{target}}, where
6066 @var{source} is the symlink that will be created and @var{target} is the
6069 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
6070 symlink pointing to the @file{bin} sub-directory of the profile.
6072 @item --save-provenance
6073 Save provenance information for the packages passed on the command line.
6074 Provenance information includes the URL and commit of the channels in use
6077 Provenance information is saved in the
6078 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
6079 usual package metadata---the name and version of each package, their
6080 propagated inputs, and so on. It is useful information to the recipient of
6081 the pack, who then knows how the pack was (supposedly) obtained.
6083 This option is not enabled by default because, like timestamps, provenance
6084 information contributes nothing to the build process. In other words, there
6085 is an infinity of channel URLs and commit IDs that can lead to the same pack.
6086 Recording such ``silent'' metadata in the output thus potentially breaks the
6087 source-to-binary bitwise reproducibility property.
6089 @item --root=@var{file}
6090 @itemx -r @var{file}
6091 @cindex garbage collector root, for packs
6092 Make @var{file} a symlink to the resulting pack, and register it as a garbage
6095 @item --localstatedir
6096 @itemx --profile-name=@var{name}
6097 Include the ``local state directory'', @file{/var/guix}, in the resulting
6098 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
6099 profile---by default @var{name} is @code{guix-profile}, which corresponds to
6100 @file{~root/.guix-profile}.
6102 @file{/var/guix} contains the store database (@pxref{The Store}) as well
6103 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
6104 the pack means that the store is ``complete'' and manageable by Guix;
6105 not providing it pack means that the store is ``dead'': items cannot be
6106 added to it or removed from it after extraction of the pack.
6108 One use case for this is the Guix self-contained binary tarball
6109 (@pxref{Binary Installation}).
6113 Print the name of the derivation that builds the pack.
6116 Use the bootstrap binaries to build the pack. This option is only
6117 useful to Guix developers.
6120 In addition, @command{guix pack} supports all the common build options
6121 (@pxref{Common Build Options}) and all the package transformation
6122 options (@pxref{Package Transformation Options}).
6125 @node The GCC toolchain
6126 @section The GCC toolchain
6130 @cindex linker wrapper
6131 @cindex toolchain, for C development
6132 @cindex toolchain, for Fortran development
6134 If you need a complete toolchain for compiling and linking C or C++
6135 source code, use the @code{gcc-toolchain} package. This package
6136 provides a complete GCC toolchain for C/C++ development, including GCC
6137 itself, the GNU C Library (headers and binaries, plus debugging symbols
6138 in the @code{debug} output), Binutils, and a linker wrapper.
6140 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
6141 passed to the linker, add corresponding @code{-rpath} arguments, and
6142 invoke the actual linker with this new set of arguments. You can instruct the
6143 wrapper to refuse to link against libraries not in the store by setting the
6144 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
6146 The package @code{gfortran-toolchain} provides a complete GCC toolchain
6147 for Fortran development. For other languages, please use
6148 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
6151 @node Invoking guix git authenticate
6152 @section Invoking @command{guix git authenticate}
6154 The @command{guix git authenticate} command authenticates a Git checkout
6155 following the same rule as for channels (@pxref{channel-authentication,
6156 channel authentication}). That is, starting from a given commit, it
6157 ensures that all subsequent commits are signed by an OpenPGP key whose
6158 fingerprint appears in the @file{.guix-authorizations} file of its
6161 You will find this command useful if you maintain a channel. But in
6162 fact, this authentication mechanism is useful in a broader context, so
6163 you might want to use it for Git repositories that have nothing to do
6166 The general syntax is:
6169 guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
6172 By default, this command authenticates the Git checkout in the current
6173 directory; it outputs nothing and exits with exit code zero on success
6174 and non-zero on failure. @var{commit} above denotes the first commit
6175 where authentication takes place, and @var{signer} is the OpenPGP
6176 fingerprint of public key used to sign @var{commit}. Together, they
6177 form a ``channel introduction'' (@pxref{channel-authentication, channel
6178 introduction}). The options below allow you to fine-tune the process.
6181 @item --repository=@var{directory}
6182 @itemx -r @var{directory}
6183 Open the Git repository in @var{directory} instead of the current
6186 @item --keyring=@var{reference}
6187 @itemx -k @var{reference}
6188 Load OpenPGP keyring from @var{reference}, the reference of a branch
6189 such as @code{origin/keyring} or @code{my-keyring}. The branch must
6190 contain OpenPGP public keys in @file{.key} files, either in binary form
6191 or ``ASCII-armored''. By default the keyring is loaded from the branch
6192 named @code{keyring}.
6195 Display commit signing statistics upon completion.
6197 @item --cache-key=@var{key}
6198 Previously-authenticated commits are cached in a file under
6199 @file{~/.cache/guix/authentication}. This option forces the cache to be
6200 stored in file @var{key} in that directory.
6202 @item --historical-authorizations=@var{file}
6203 By default, any commit whose parent commit(s) lack the
6204 @file{.guix-authorizations} file is considered inauthentic. In
6205 contrast, this option considers the authorizations in @var{file} for any
6206 commit that lacks @file{.guix-authorizations}. The format of @var{file}
6207 is the same as that of @file{.guix-authorizations}
6208 (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
6212 @c *********************************************************************
6213 @node Programming Interface
6214 @chapter Programming Interface
6216 GNU Guix provides several Scheme programming interfaces (APIs) to
6217 define, build, and query packages. The first interface allows users to
6218 write high-level package definitions. These definitions refer to
6219 familiar packaging concepts, such as the name and version of a package,
6220 its build system, and its dependencies. These definitions can then be
6221 turned into concrete build actions.
6223 Build actions are performed by the Guix daemon, on behalf of users. In a
6224 standard setup, the daemon has write access to the store---the
6225 @file{/gnu/store} directory---whereas users do not. The recommended
6226 setup also has the daemon perform builds in chroots, under specific
6227 build users, to minimize interference with the rest of the system.
6230 Lower-level APIs are available to interact with the daemon and the
6231 store. To instruct the daemon to perform a build action, users actually
6232 provide it with a @dfn{derivation}. A derivation is a low-level
6233 representation of the build actions to be taken, and the environment in
6234 which they should occur---derivations are to package definitions what
6235 assembly is to C programs. The term ``derivation'' comes from the fact
6236 that build results @emph{derive} from them.
6238 This chapter describes all these APIs in turn, starting from high-level
6239 package definitions.
6242 * Package Modules:: Packages from the programmer's viewpoint.
6243 * Defining Packages:: Defining new packages.
6244 * Defining Package Variants:: Customizing packages.
6245 * Build Systems:: Specifying how packages are built.
6246 * Build Phases:: Phases of the build process of a package.
6247 * Build Utilities:: Helpers for your package definitions and more.
6248 * The Store:: Manipulating the package store.
6249 * Derivations:: Low-level interface to package derivations.
6250 * The Store Monad:: Purely functional interface to the store.
6251 * G-Expressions:: Manipulating build expressions.
6252 * Invoking guix repl:: Programming Guix in Guile
6255 @node Package Modules
6256 @section Package Modules
6258 From a programming viewpoint, the package definitions of the
6259 GNU distribution are provided by Guile modules in the @code{(gnu packages
6260 @dots{})} name space@footnote{Note that packages under the @code{(gnu
6261 packages @dots{})} module name space are not necessarily ``GNU
6262 packages''. This module naming scheme follows the usual Guile module
6263 naming convention: @code{gnu} means that these modules are distributed
6264 as part of the GNU system, and @code{packages} identifies modules that
6265 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
6266 Reference Manual}). For instance, the @code{(gnu packages emacs)}
6267 module exports a variable named @code{emacs}, which is bound to a
6268 @code{<package>} object (@pxref{Defining Packages}).
6270 The @code{(gnu packages @dots{})} module name space is
6271 automatically scanned for packages by the command-line tools. For
6272 instance, when running @code{guix install emacs}, all the @code{(gnu
6273 packages @dots{})} modules are scanned until one that exports a package
6274 object whose name is @code{emacs} is found. This package search
6275 facility is implemented in the @code{(gnu packages)} module.
6277 @cindex customization, of packages
6278 @cindex package module search path
6279 Users can store package definitions in modules with different
6280 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
6281 name and module name must match. For instance, the @code{(my-packages
6282 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
6283 relative to the load path specified with @option{--load-path} or
6284 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
6285 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
6286 these package definitions visible to the user interfaces:
6290 By adding the directory containing your package modules to the search path
6291 with the @code{-L} flag of @command{guix package} and other commands
6292 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
6293 environment variable described below.
6296 By defining a @dfn{channel} and configuring @command{guix pull} so that it
6297 pulls from it. A channel is essentially a Git repository containing package
6298 modules. @xref{Channels}, for more information on how to define and use
6302 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
6304 @defvr {Environment Variable} GUIX_PACKAGE_PATH
6305 This is a colon-separated list of directories to search for additional
6306 package modules. Directories listed in this variable take precedence
6307 over the own modules of the distribution.
6310 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
6311 each package is built based solely on other packages in the
6312 distribution. The root of this dependency graph is a small set of
6313 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
6314 bootstrap)} module. For more information on bootstrapping,
6315 @pxref{Bootstrapping}.
6317 @node Defining Packages
6318 @section Defining Packages
6320 The high-level interface to package definitions is implemented in the
6321 @code{(guix packages)} and @code{(guix build-system)} modules. As an
6322 example, the package definition, or @dfn{recipe}, for the GNU Hello
6323 package looks like this:
6326 (define-module (gnu packages hello)
6327 #:use-module (guix packages)
6328 #:use-module (guix download)
6329 #:use-module (guix build-system gnu)
6330 #:use-module (guix licenses)
6331 #:use-module (gnu packages gawk))
6333 (define-public hello
6339 (uri (string-append "mirror://gnu/hello/hello-" version
6343 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
6344 (build-system gnu-build-system)
6345 (arguments '(#:configure-flags '("--enable-silent-rules")))
6346 (inputs `(("gawk" ,gawk)))
6347 (synopsis "Hello, GNU world: An example GNU package")
6348 (description "Guess what GNU Hello prints!")
6349 (home-page "https://www.gnu.org/software/hello/")
6354 Without being a Scheme expert, the reader may have guessed the meaning
6355 of the various fields here. This expression binds the variable
6356 @code{hello} to a @code{<package>} object, which is essentially a record
6357 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
6358 This package object can be inspected using procedures found in the
6359 @code{(guix packages)} module; for instance, @code{(package-name hello)}
6360 returns---surprise!---@code{"hello"}.
6362 With luck, you may be able to import part or all of the definition of
6363 the package you are interested in from another repository, using the
6364 @code{guix import} command (@pxref{Invoking guix import}).
6366 In the example above, @code{hello} is defined in a module of its own,
6367 @code{(gnu packages hello)}. Technically, this is not strictly
6368 necessary, but it is convenient to do so: all the packages defined in
6369 modules under @code{(gnu packages @dots{})} are automatically known to
6370 the command-line tools (@pxref{Package Modules}).
6372 There are a few points worth noting in the above package definition:
6376 The @code{source} field of the package is an @code{<origin>} object
6377 (@pxref{origin Reference}, for the complete reference).
6378 Here, the @code{url-fetch} method from @code{(guix download)} is used,
6379 meaning that the source is a file to be downloaded over FTP or HTTP.
6381 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
6382 the GNU mirrors defined in @code{(guix download)}.
6384 The @code{sha256} field specifies the expected SHA256 hash of the file
6385 being downloaded. It is mandatory, and allows Guix to check the
6386 integrity of the file. The @code{(base32 @dots{})} form introduces the
6387 base32 representation of the hash. You can obtain this information with
6388 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
6389 hash} (@pxref{Invoking guix hash}).
6392 When needed, the @code{origin} form can also have a @code{patches} field
6393 listing patches to be applied, and a @code{snippet} field giving a
6394 Scheme expression to modify the source code.
6397 @cindex GNU Build System
6398 The @code{build-system} field specifies the procedure to build the
6399 package (@pxref{Build Systems}). Here, @code{gnu-build-system}
6400 represents the familiar GNU Build System, where packages may be
6401 configured, built, and installed with the usual @code{./configure &&
6402 make && make check && make install} command sequence.
6404 When you start packaging non-trivial software, you may need tools to
6405 manipulate those build phases, manipulate files, and so on. @xref{Build
6406 Utilities}, for more on this.
6409 The @code{arguments} field specifies options for the build system
6410 (@pxref{Build Systems}). Here it is interpreted by
6411 @code{gnu-build-system} as a request run @file{configure} with the
6412 @option{--enable-silent-rules} flag.
6418 What about these quote (@code{'}) characters? They are Scheme syntax to
6419 introduce a literal list; @code{'} is synonymous with @code{quote}.
6420 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
6421 for details. Here the value of the @code{arguments} field is a list of
6422 arguments passed to the build system down the road, as with @code{apply}
6423 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
6426 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
6427 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
6428 @code{#:configure-flags} is a keyword used to pass a keyword argument
6429 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
6433 The @code{inputs} field specifies inputs to the build process---i.e.,
6434 build-time or run-time dependencies of the package. Here, we define an
6435 input called @code{"gawk"} whose value is that of the @code{gawk}
6436 variable; @code{gawk} is itself bound to a @code{<package>} object.
6438 @cindex backquote (quasiquote)
6441 @cindex comma (unquote)
6445 @findex unquote-splicing
6446 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
6447 us to introduce a literal list in the @code{inputs} field, while
6448 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
6449 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
6452 Note that GCC, Coreutils, Bash, and other essential tools do not need to
6453 be specified as inputs here. Instead, @code{gnu-build-system} takes care
6454 of ensuring that they are present (@pxref{Build Systems}).
6456 However, any other dependencies need to be specified in the
6457 @code{inputs} field. Any dependency not specified here will simply be
6458 unavailable to the build process, possibly leading to a build failure.
6461 @xref{package Reference}, for a full description of possible fields.
6463 Once a package definition is in place, the
6464 package may actually be built using the @code{guix build} command-line
6465 tool (@pxref{Invoking guix build}), troubleshooting any build failures
6466 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
6467 package definition using the @command{guix edit} command
6468 (@pxref{Invoking guix edit}).
6469 @xref{Packaging Guidelines}, for
6470 more information on how to test package definitions, and
6471 @ref{Invoking guix lint}, for information on how to check a definition
6472 for style conformance.
6473 @vindex GUIX_PACKAGE_PATH
6474 Lastly, @pxref{Channels}, for information
6475 on how to extend the distribution by adding your own package definitions
6478 Finally, updating the package definition to a new upstream version
6479 can be partly automated by the @command{guix refresh} command
6480 (@pxref{Invoking guix refresh}).
6482 Behind the scenes, a derivation corresponding to the @code{<package>}
6483 object is first computed by the @code{package-derivation} procedure.
6484 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
6485 The build actions it prescribes may then be realized by using the
6486 @code{build-derivations} procedure (@pxref{The Store}).
6488 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
6489 Return the @code{<derivation>} object of @var{package} for @var{system}
6490 (@pxref{Derivations}).
6492 @var{package} must be a valid @code{<package>} object, and @var{system}
6493 must be a string denoting the target system type---e.g.,
6494 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
6495 must be a connection to the daemon, which operates on the store
6496 (@pxref{The Store}).
6500 @cindex cross-compilation
6501 Similarly, it is possible to compute a derivation that cross-builds a
6502 package for some other system:
6504 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
6505 @var{package} @var{target} [@var{system}]
6506 Return the @code{<derivation>} object of @var{package} cross-built from
6507 @var{system} to @var{target}.
6509 @var{target} must be a valid GNU triplet denoting the target hardware
6510 and operating system, such as @code{"aarch64-linux-gnu"}
6511 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
6514 Once you have package definitions, you can easily define @emph{variants}
6515 of those packages. @xref{Defining Package Variants}, for more on that.
6518 * package Reference:: The package data type.
6519 * origin Reference:: The origin data type.
6523 @node package Reference
6524 @subsection @code{package} Reference
6526 This section summarizes all the options available in @code{package}
6527 declarations (@pxref{Defining Packages}).
6529 @deftp {Data Type} package
6530 This is the data type representing a package recipe.
6534 The name of the package, as a string.
6536 @item @code{version}
6537 The version of the package, as a string.
6540 An object telling how the source code for the package should be
6541 acquired. Most of the time, this is an @code{origin} object, which
6542 denotes a file fetched from the Internet (@pxref{origin Reference}). It
6543 can also be any other ``file-like'' object such as a @code{local-file},
6544 which denotes a file from the local file system (@pxref{G-Expressions,
6545 @code{local-file}}).
6547 @item @code{build-system}
6548 The build system that should be used to build the package (@pxref{Build
6551 @item @code{arguments} (default: @code{'()})
6552 The arguments that should be passed to the build system. This is a
6553 list, typically containing sequential keyword-value pairs.
6555 @item @code{inputs} (default: @code{'()})
6556 @itemx @code{native-inputs} (default: @code{'()})
6557 @itemx @code{propagated-inputs} (default: @code{'()})
6558 @cindex inputs, of packages
6559 These fields list dependencies of the package. Each one is a list of
6560 tuples, where each tuple has a label for the input (a string) as its
6561 first element, a package, origin, or derivation as its second element,
6562 and optionally the name of the output thereof that should be used, which
6563 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
6564 more on package outputs). For example, the list below specifies three
6568 `(("libffi" ,libffi)
6569 ("libunistring" ,libunistring)
6570 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
6573 @cindex cross compilation, package dependencies
6574 The distinction between @code{native-inputs} and @code{inputs} is
6575 necessary when considering cross-compilation. When cross-compiling,
6576 dependencies listed in @code{inputs} are built for the @emph{target}
6577 architecture; conversely, dependencies listed in @code{native-inputs}
6578 are built for the architecture of the @emph{build} machine.
6580 @code{native-inputs} is typically used to list tools needed at
6581 build time, but not at run time, such as Autoconf, Automake, pkg-config,
6582 Gettext, or Bison. @command{guix lint} can report likely mistakes in
6583 this area (@pxref{Invoking guix lint}).
6585 @anchor{package-propagated-inputs}
6586 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
6587 specified packages will be automatically installed to profiles
6588 (@pxref{Features, the role of profiles in Guix}) alongside the package
6589 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
6590 package}}, for information on how @command{guix package} deals with
6593 For example this is necessary when packaging a C/C++ library that needs
6594 headers of another library to compile, or when a pkg-config file refers
6595 to another one @i{via} its @code{Requires} field.
6597 Another example where @code{propagated-inputs} is useful is for languages
6598 that lack a facility to record the run-time search path akin to the
6599 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
6600 more. When packaging libraries written in those languages, ensure they
6601 can find library code they depend on at run time by listing run-time
6602 dependencies in @code{propagated-inputs} rather than @code{inputs}.
6604 @item @code{outputs} (default: @code{'("out")})
6605 The list of output names of the package. @xref{Packages with Multiple
6606 Outputs}, for typical uses of additional outputs.
6608 @item @code{native-search-paths} (default: @code{'()})
6609 @itemx @code{search-paths} (default: @code{'()})
6610 A list of @code{search-path-specification} objects describing
6611 search-path environment variables honored by the package.
6613 @item @code{replacement} (default: @code{#f})
6614 This must be either @code{#f} or a package object that will be used as a
6615 @dfn{replacement} for this package. @xref{Security Updates, grafts},
6618 @item @code{synopsis}
6619 A one-line description of the package.
6621 @item @code{description}
6622 A more elaborate description of the package.
6624 @item @code{license}
6625 @cindex license, of packages
6626 The license of the package; a value from @code{(guix licenses)},
6627 or a list of such values.
6629 @item @code{home-page}
6630 The URL to the home-page of the package, as a string.
6632 @item @code{supported-systems} (default: @code{%supported-systems})
6633 The list of systems supported by the package, as strings of the form
6634 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
6636 @item @code{location} (default: source location of the @code{package} form)
6637 The source location of the package. It is useful to override this when
6638 inheriting from another package, in which case this field is not
6639 automatically corrected.
6643 @deffn {Scheme Syntax} this-package
6644 When used in the @emph{lexical scope} of a package field definition, this
6645 identifier resolves to the package being defined.
6647 The example below shows how to add a package as a native input of itself when
6655 ;; When cross-compiled, Guile, for example, depends on
6656 ;; a native version of itself. Add it here.
6657 (native-inputs (if (%current-target-system)
6658 `(("self" ,this-package))
6662 It is an error to refer to @code{this-package} outside a package definition.
6665 Because packages are regular Scheme objects that capture a complete
6666 dependency graph and associated build procedures, it is often useful to
6667 write procedures that take a package and return a modified version
6668 thereof according to some parameters. Below are a few examples.
6670 @cindex tool chain, choosing a package's tool chain
6671 @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
6672 Return a variant of @var{package} that uses @var{toolchain} instead of
6673 the default GNU C/C++ toolchain. @var{toolchain} must be a list of
6674 inputs (label/package tuples) providing equivalent functionality, such
6675 as the @code{gcc-toolchain} package.
6677 The example below returns a variant of the @code{hello} package built
6678 with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
6679 GNU C Library) instead of the default tool chain:
6682 (let ((toolchain (specification->package "gcc-toolchain@@10")))
6683 (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
6686 The build tool chain is part of the @dfn{implicit inputs} of
6687 packages---it's usually not listed as part of the various ``inputs''
6688 fields and is instead pulled in by the build system. Consequently, this
6689 procedure works by changing the build system of @var{package} so that it
6690 pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
6691 for more on build systems.
6694 @node origin Reference
6695 @subsection @code{origin} Reference
6697 This section documents @dfn{origins}. An @code{origin} declaration
6698 specifies data that must be ``produced''---downloaded, usually---and
6699 whose content hash is known in advance. Origins are primarily used to
6700 represent the source code of packages (@pxref{Defining Packages}). For
6701 that reason, the @code{origin} form allows you to declare patches to
6702 apply to the original source code as well as code snippets to modify it.
6704 @deftp {Data Type} origin
6705 This is the data type representing a source code origin.
6709 An object containing the URI of the source. The object type depends on
6710 the @code{method} (see below). For example, when using the
6711 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
6712 values are: a URL represented as a string, or a list thereof.
6714 @cindex fixed-output derivations, for download
6716 A monadic procedure that handles the given URI. The procedure must
6717 accept at least three arguments: the value of the @code{uri} field and
6718 the hash algorithm and hash value specified by the @code{hash} field.
6719 It must return a store item or a derivation in the store monad
6720 (@pxref{The Store Monad}); most methods return a fixed-output derivation
6721 (@pxref{Derivations}).
6723 Commonly used methods include @code{url-fetch}, which fetches data from
6724 a URL, and @code{git-fetch}, which fetches data from a Git repository
6728 A bytevector containing the SHA-256 hash of the source. This is
6729 equivalent to providing a @code{content-hash} SHA256 object in the
6730 @code{hash} field described below.
6733 The @code{content-hash} object of the source---see below for how to use
6734 @code{content-hash}.
6736 You can obtain this information using @code{guix download}
6737 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
6740 @item @code{file-name} (default: @code{#f})
6741 The file name under which the source code should be saved. When this is
6742 @code{#f}, a sensible default value will be used in most cases. In case
6743 the source is fetched from a URL, the file name from the URL will be
6744 used. For version control checkouts, it is recommended to provide the
6745 file name explicitly because the default is not very descriptive.
6747 @item @code{patches} (default: @code{'()})
6748 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
6749 file-like objects}) pointing to patches to be applied to the source.
6751 This list of patches must be unconditional. In particular, it cannot
6752 depend on the value of @code{%current-system} or
6753 @code{%current-target-system}.
6755 @item @code{snippet} (default: @code{#f})
6756 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
6757 in the source directory. This is a convenient way to modify the source,
6758 sometimes more convenient than a patch.
6760 @item @code{patch-flags} (default: @code{'("-p1")})
6761 A list of command-line flags that should be passed to the @code{patch}
6764 @item @code{patch-inputs} (default: @code{#f})
6765 Input packages or derivations to the patching process. When this is
6766 @code{#f}, the usual set of inputs necessary for patching are provided,
6767 such as GNU@tie{}Patch.
6769 @item @code{modules} (default: @code{'()})
6770 A list of Guile modules that should be loaded during the patching
6771 process and while running the code in the @code{snippet} field.
6773 @item @code{patch-guile} (default: @code{#f})
6774 The Guile package that should be used in the patching process. When
6775 this is @code{#f}, a sensible default is used.
6779 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
6780 Construct a content hash object for the given @var{algorithm}, and with
6781 @var{value} as its hash value. When @var{algorithm} is omitted, assume
6782 it is @code{sha256}.
6784 @var{value} can be a literal string, in which case it is base32-decoded,
6785 or it can be a bytevector.
6787 The following forms are all equivalent:
6790 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
6791 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
6793 (content-hash (base32
6794 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
6795 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
6799 Technically, @code{content-hash} is currently implemented as a macro.
6800 It performs sanity checks at macro-expansion time, when possible, such
6801 as ensuring that @var{value} has the right size for @var{algorithm}.
6804 As we have seen above, how exactly the data an origin refers to is
6805 retrieved is determined by its @code{method} field. The @code{(guix
6806 download)} module provides the most common method, @code{url-fetch},
6809 @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
6810 [name] [#:executable? #f]
6811 Return a fixed-output derivation that fetches data from @var{url} (a
6812 string, or a list of strings denoting alternate URLs), which is expected
6813 to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
6814 the file name is the base name of URL; optionally, @var{name} can
6815 specify a different file name. When @var{executable?} is true, make the
6816 downloaded file executable.
6818 When one of the URL starts with @code{mirror://}, then its host part is
6819 interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
6821 Alternatively, when URL starts with @code{file://}, return the
6822 corresponding file name in the store.
6825 Likewise, the @code{(guix git-download)} module defines the
6826 @code{git-fetch} origin method, which fetches data from a Git version
6827 control repository, and the @code{git-reference} data type to describe
6828 the repository and revision to fetch.
6830 @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
6831 Return a fixed-output derivation that fetches @var{ref}, a
6832 @code{<git-reference>} object. The output is expected to have recursive
6833 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
6834 the file name, or a generic name if @code{#f}.
6837 @deftp {Data Type} git-reference
6838 This data type represents a Git reference for @code{git-fetch} to
6843 The URL of the Git repository to clone.
6846 This string denotes either the commit to fetch (a hexadecimal string,
6847 either the full SHA1 commit or a ``short'' commit string; the latter is
6848 not recommended) or the tag to fetch.
6850 @item @code{recursive?} (default: @code{#f})
6851 This Boolean indicates whether to recursively fetch Git sub-modules.
6854 The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
6859 (url "https://git.savannah.gnu.org/git/hello.git")
6863 This is equivalent to the reference below, which explicitly names the
6868 (url "https://git.savannah.gnu.org/git/hello.git")
6869 (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
6873 For Mercurial repositories, the module @code{(guix hg-download)} defines
6874 the @code{hg-fetch} origin method and @code{hg-reference} data type for
6875 support of the Mercurial version control system.
6877 @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
6879 Return a fixed-output derivation that fetches @var{ref}, a
6880 @code{<hg-reference>} object. The output is expected to have recursive
6881 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
6882 the file name, or a generic name if @code{#false}.
6885 @node Defining Package Variants
6886 @section Defining Package Variants
6888 @cindex customizing packages
6889 @cindex variants, of packages
6890 One of the nice things with Guix is that, given a package definition,
6891 you can easily @emph{derive} variants of that package---for a different
6892 upstream version, with different dependencies, different compilation
6893 options, and so on. Some of these custom packages can be defined
6894 straight from the command line (@pxref{Package Transformation Options}).
6895 This section describes how to define package variants in code. This can
6896 be useful in ``manifests'' (@pxref{profile-manifest,
6897 @option{--manifest}}) and in your own package collection
6898 (@pxref{Creating a Channel}), among others!
6900 @cindex inherit, for package definitions
6901 As discussed earlier, packages are first-class objects in the Scheme
6902 language. The @code{(guix packages)} module provides the @code{package}
6903 construct to define new package objects (@pxref{package Reference}).
6904 The easiest way to define a package variant is using the @code{inherit}
6905 keyword together with @code{package}. This allows you to inherit from a
6906 package definition while overriding the fields you want.
6908 For example, given the @code{hello} variable, which contains a
6909 definition for the current version of GNU@tie{}Hello, here's how you
6910 would define a variant for version 2.2 (released in 2006, it's
6914 (use-modules (gnu packages base)) ;for 'hello'
6922 (uri (string-append "mirror://gnu/hello/hello-" version
6926 "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
6929 The example above corresponds to what the @option{--with-source} package
6930 transformation option does. Essentially @code{hello-2.2} preserves all
6931 the fields of @code{hello}, except @code{version} and @code{source},
6932 which it overrides. Note that the original @code{hello} variable is
6933 still there, in the @code{(gnu packages base)} module, unchanged. When
6934 you define a custom package like this, you are really @emph{adding} a
6935 new package definition; the original one remains available.
6937 You can just as well define variants with a different set of
6938 dependencies than the original package. For example, the default
6939 @code{gdb} package depends on @code{guile}, but since that is an
6940 optional dependency, you can define a variant that removes that
6944 (use-modules (gnu packages gdb) ;for 'gdb'
6945 (srfi srfi-1)) ;for 'alist-delete'
6947 (define gdb-sans-guile
6950 (inputs (alist-delete "guile"
6951 (package-inputs gdb)))))
6954 The @code{alist-delete} call above removes the tuple from the
6955 @code{inputs} field that has @code{"guile"} as its first element
6956 (@pxref{SRFI-1 Association Lists,,, guile, GNU Guile Reference
6959 In some cases, you may find it useful to write functions
6960 (``procedures'', in Scheme parlance) that return a package based on some
6961 parameters. For example, consider the @code{luasocket} library for the
6962 Lua programming language. We want to create @code{luasocket} packages
6963 for major versions of Lua. One way to do that is to define a procedure
6964 that takes a Lua package and returns a @code{luasocket} package that
6968 (define (make-lua-socket name lua)
6969 ;; Return a luasocket package built with LUA.
6973 ;; several fields omitted
6976 (synopsis "Socket library for Lua")))
6978 (define-public lua5.1-socket
6979 (make-lua-socket "lua5.1-socket" lua-5.1))
6981 (define-public lua5.2-socket
6982 (make-lua-socket "lua5.2-socket" lua-5.2))
6985 Here we have defined packages @code{lua5.1-socket} and
6986 @code{lua5.2-socket} by calling @code{make-lua-socket} with different
6987 arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
6988 more info on procedures. Having top-level public definitions for these
6989 two packages means that they can be referred to from the command line
6990 (@pxref{Package Modules}).
6992 @cindex package transformations
6993 These are pretty simple package variants. As a convenience, the
6994 @code{(guix transformations)} module provides a high-level interface
6995 that directly maps to the more sophisticated package transformation
6996 options (@pxref{Package Transformation Options}):
6998 @deffn {Scheme Procedure} options->transformation @var{opts}
6999 Return a procedure that, when passed an object to build (package,
7000 derivation, etc.), applies the transformations specified by @var{opts} and returns
7001 the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
7004 ((with-branch . "guile-gcrypt=master")
7005 (without-tests . "libgcrypt"))
7008 Each symbol names a transformation and the corresponding string is an argument
7009 to that transformation.
7012 For instance, a manifest equivalent to this command:
7016 --with-branch=guile-gcrypt=master \
7017 --with-debug-info=zlib
7021 ... would look like this:
7024 (use-modules (guix transformations))
7027 ;; The package transformation procedure.
7028 (options->transformation
7029 '((with-branch . "guile-gcrypt=master")
7030 (with-debug-info . "zlib"))))
7033 (list (transform (specification->package "guix"))))
7036 @cindex input rewriting
7037 @cindex dependency graph rewriting
7038 The @code{options->transformation} procedure is convenient, but it's
7039 perhaps also not as flexible as you may like. How is it implemented?
7040 The astute reader probably noticed that most package transformation
7041 options go beyond the superficial changes shown in the first examples of
7042 this section: they involve @dfn{input rewriting}, whereby the dependency
7043 graph of a package is rewritten by replacing specific inputs by others.
7045 Dependency graph rewriting, for the purposes of swapping packages in the
7046 graph, is what the @code{package-input-rewriting} procedure in
7047 @code{(guix packages)} implements.
7049 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
7050 [@var{rewrite-name}] [#:deep? #t]
7051 Return a procedure that, when passed a package, replaces its direct and
7052 indirect dependencies, including implicit inputs when @var{deep?} is
7053 true, according to @var{replacements}. @var{replacements} is a list of
7054 package pairs; the first element of each pair is the package to replace,
7055 and the second one is the replacement.
7057 Optionally, @var{rewrite-name} is a one-argument procedure that takes
7058 the name of a package and returns its new name after rewrite.
7062 Consider this example:
7065 (define libressl-instead-of-openssl
7066 ;; This is a procedure to replace OPENSSL by LIBRESSL,
7068 (package-input-rewriting `((,openssl . ,libressl))))
7070 (define git-with-libressl
7071 (libressl-instead-of-openssl git))
7075 Here we first define a rewriting procedure that replaces @var{openssl}
7076 with @var{libressl}. Then we use it to define a @dfn{variant} of the
7077 @var{git} package that uses @var{libressl} instead of @var{openssl}.
7078 This is exactly what the @option{--with-input} command-line option does
7079 (@pxref{Package Transformation Options, @option{--with-input}}).
7081 The following variant of @code{package-input-rewriting} can match packages to
7082 be replaced by name rather than by identity.
7084 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
7085 Return a procedure that, given a package, applies the given
7086 @var{replacements} to all the package graph, including implicit inputs
7087 unless @var{deep?} is false. @var{replacements} is a list of
7088 spec/procedures pair; each spec is a package specification such as
7089 @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
7090 package and returns a replacement for that package.
7093 The example above could be rewritten this way:
7096 (define libressl-instead-of-openssl
7097 ;; Replace all the packages called "openssl" with LibreSSL.
7098 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
7101 The key difference here is that, this time, packages are matched by spec and
7102 not by identity. In other words, any package in the graph that is called
7103 @code{openssl} will be replaced.
7105 A more generic procedure to rewrite a package dependency graph is
7106 @code{package-mapping}: it supports arbitrary changes to nodes in the
7109 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
7110 Return a procedure that, given a package, applies @var{proc} to all the packages
7111 depended on and returns the resulting package. The procedure stops recursion
7112 when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
7113 applied to implicit inputs as well.
7118 @section Build Systems
7120 @cindex build system
7121 Each package definition specifies a @dfn{build system} and arguments for
7122 that build system (@pxref{Defining Packages}). This @code{build-system}
7123 field represents the build procedure of the package, as well as implicit
7124 dependencies of that build procedure.
7126 Build systems are @code{<build-system>} objects. The interface to
7127 create and manipulate them is provided by the @code{(guix build-system)}
7128 module, and actual build systems are exported by specific modules.
7130 @cindex bag (low-level package representation)
7131 Under the hood, build systems first compile package objects to
7132 @dfn{bags}. A @dfn{bag} is like a package, but with less
7133 ornamentation---in other words, a bag is a lower-level representation of
7134 a package, which includes all the inputs of that package, including some
7135 that were implicitly added by the build system. This intermediate
7136 representation is then compiled to a derivation (@pxref{Derivations}).
7137 The @code{package-with-c-toolchain} is an example of a way to change the
7138 implicit inputs that a package's build system pulls in (@pxref{package
7139 Reference, @code{package-with-c-toolchain}}).
7141 Build systems accept an optional list of @dfn{arguments}. In package
7142 definitions, these are passed @i{via} the @code{arguments} field
7143 (@pxref{Defining Packages}). They are typically keyword arguments
7144 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
7145 Guile Reference Manual}). The value of these arguments is usually
7146 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
7147 by the daemon (@pxref{Derivations}).
7149 The main build system is @code{gnu-build-system}, which implements the
7150 standard build procedure for GNU and many other packages. It
7151 is provided by the @code{(guix build-system gnu)} module.
7153 @defvr {Scheme Variable} gnu-build-system
7154 @code{gnu-build-system} represents the GNU Build System, and variants
7155 thereof (@pxref{Configuration, configuration and makefile conventions,,
7156 standards, GNU Coding Standards}).
7158 @cindex build phases
7159 In a nutshell, packages using it are configured, built, and installed with
7160 the usual @code{./configure && make && make check && make install}
7161 command sequence. In practice, a few additional steps are often needed.
7162 All these steps are split up in separate @dfn{phases},
7163 notably@footnote{Please see the @code{(guix build gnu-build-system)}
7164 modules for more details about the build phases.}:
7168 Unpack the source tarball, and change the current directory to the
7169 extracted source tree. If the source is actually a directory, copy it
7170 to the build tree, and enter that directory.
7172 @item patch-source-shebangs
7173 Patch shebangs encountered in source files so they refer to the right
7174 store file names. For instance, this changes @code{#!/bin/sh} to
7175 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
7178 Run the @file{configure} script with a number of default options, such
7179 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
7180 by the @code{#:configure-flags} argument.
7183 Run @code{make} with the list of flags specified with
7184 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
7185 (the default), build with @code{make -j}.
7188 Run @code{make check}, or some other target specified with
7189 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
7190 @code{#:parallel-tests?} argument is true (the default), run @code{make
7194 Run @code{make install} with the flags listed in @code{#:make-flags}.
7196 @item patch-shebangs
7197 Patch shebangs on the installed executable files.
7200 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
7201 is false), copying them to the @code{debug} output when available
7202 (@pxref{Installing Debugging Files}).
7205 @vindex %standard-phases
7206 The build-side module @code{(guix build gnu-build-system)} defines
7207 @code{%standard-phases} as the default list of build phases.
7208 @code{%standard-phases} is a list of symbol/procedure pairs, where the
7209 procedure implements the actual phase.
7211 @xref{Build Phases}, for more info on build phases and ways to customize
7214 In addition, this build system ensures that the ``standard'' environment
7215 for GNU packages is available. This includes tools such as GCC, libc,
7216 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
7217 build-system gnu)} module for a complete list). We call these the
7218 @dfn{implicit inputs} of a package, because package definitions do not
7219 have to mention them.
7222 Other @code{<build-system>} objects are defined to support other
7223 conventions and tools used by free software packages. They inherit most
7224 of @code{gnu-build-system}, and differ mainly in the set of inputs
7225 implicitly added to the build process, and in the list of phases
7226 executed. Some of these build systems are listed below.
7228 @defvr {Scheme Variable} ant-build-system
7229 This variable is exported by @code{(guix build-system ant)}. It
7230 implements the build procedure for Java packages that can be built with
7231 @url{https://ant.apache.org/, Ant build tool}.
7233 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
7234 provided by the @code{icedtea} package to the set of inputs. Different
7235 packages can be specified with the @code{#:ant} and @code{#:jdk}
7236 parameters, respectively.
7238 When the original package does not provide a suitable Ant build file,
7239 the parameter @code{#:jar-name} can be used to generate a minimal Ant
7240 build file @file{build.xml} with tasks to build the specified jar
7241 archive. In this case the parameter @code{#:source-dir} can be used to
7242 specify the source sub-directory, defaulting to ``src''.
7244 The @code{#:main-class} parameter can be used with the minimal ant
7245 buildfile to specify the main class of the resulting jar. This makes the
7246 jar file executable. The @code{#:test-include} parameter can be used to
7247 specify the list of junit tests to run. It defaults to
7248 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
7249 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
7250 because abstract classes cannot be run as tests.
7252 The parameter @code{#:build-target} can be used to specify the Ant task
7253 that should be run during the @code{build} phase. By default the
7254 ``jar'' task will be run.
7258 @defvr {Scheme Variable} android-ndk-build-system
7259 @cindex Android distribution
7260 @cindex Android NDK build system
7261 This variable is exported by @code{(guix build-system android-ndk)}. It
7262 implements a build procedure for Android NDK (native development kit)
7263 packages using a Guix-specific build process.
7265 The build system assumes that packages install their public interface
7266 (header) files to the subdirectory @file{include} of the @code{out} output and
7267 their libraries to the subdirectory @file{lib} the @code{out} output.
7269 It's also assumed that the union of all the dependencies of a package
7270 has no conflicting files.
7272 For the time being, cross-compilation is not supported - so right now
7273 the libraries and header files are assumed to be host tools.
7277 @defvr {Scheme Variable} asdf-build-system/source
7278 @defvrx {Scheme Variable} asdf-build-system/sbcl
7279 @defvrx {Scheme Variable} asdf-build-system/ecl
7281 These variables, exported by @code{(guix build-system asdf)}, implement
7282 build procedures for Common Lisp packages using
7283 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
7284 definition facility for Common Lisp programs and libraries.
7286 The @code{asdf-build-system/source} system installs the packages in
7287 source form, and can be loaded using any common lisp implementation, via
7288 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
7289 systems in the format which a particular implementation understands.
7290 These build systems can also be used to produce executable programs, or
7291 lisp images which contain a set of packages pre-loaded.
7293 The build system uses naming conventions. For binary packages, the
7294 package name should be prefixed with the lisp implementation, such as
7295 @code{sbcl-} for @code{asdf-build-system/sbcl}.
7297 Additionally, the corresponding source package should be labeled using
7298 the same convention as python packages (see @ref{Python Modules}), using
7299 the @code{cl-} prefix.
7301 In order to create executable programs and images, the build-side
7302 procedures @code{build-program} and @code{build-image} can be used.
7303 They should be called in a build phase after the
7304 @code{create-asdf-configuration} phase, so that the system which was
7305 just built can be used within the resulting image. @code{build-program}
7306 requires a list of Common Lisp expressions to be passed as the
7307 @code{#:entry-program} argument.
7309 By default, all the @file{.asd} files present in the sources are read to
7310 find system definitions. The @code{#:asd-files} parameter can be used
7311 to specify the list of @file{.asd} files to read. Furthermore, if the
7312 package defines a system for its tests in a separate file, it will be
7313 loaded before the tests are run if it is specified by the
7314 @code{#:test-asd-file} parameter. If it is not set, the files
7315 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
7316 and @code{test.asd} will be tried if they exist.
7318 If for some reason the package must be named in a different way than the
7319 naming conventions suggest, or if several systems must be compiled, the
7320 @code{#:asd-systems} parameter can be used to specify the list of system
7325 @defvr {Scheme Variable} cargo-build-system
7326 @cindex Rust programming language
7327 @cindex Cargo (Rust build system)
7328 This variable is exported by @code{(guix build-system cargo)}. It
7329 supports builds of packages using Cargo, the build tool of the
7330 @uref{https://www.rust-lang.org, Rust programming language}.
7332 It adds @code{rustc} and @code{cargo} to the set of inputs.
7333 A different Rust package can be specified with the @code{#:rust} parameter.
7335 Regular cargo dependencies should be added to the package definition via the
7336 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
7337 spec can be a package or a source definition. Note that the spec must
7338 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
7339 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
7340 should be added to the package definition via the
7341 @code{#:cargo-development-inputs} parameter.
7343 In its @code{configure} phase, this build system will make any source inputs
7344 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
7345 parameters available to cargo. It will also remove an included
7346 @code{Cargo.lock} file to be recreated by @code{cargo} during the
7347 @code{build} phase. The @code{install} phase installs the binaries
7348 defined by the crate.
7351 @defvr {Scheme Variable} chicken-build-system
7352 This variable is exported by @code{(guix build-system chicken)}. It
7353 builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
7354 ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
7355 gets compiled by a C compiler, in this case GCC.
7357 This build system adds @code{chicken} to the package inputs, as well as
7358 the packages of @code{gnu-build-system}.
7360 The build system can't (yet) deduce the egg's name automatically, so just like
7361 with @code{go-build-system} and its @code{#:import-path}, you should define
7362 @code{#:egg-name} in the package's @code{arguments} field.
7364 For example, if you are packaging the @code{srfi-1} egg:
7367 (arguments '(#:egg-name "srfi-1"))
7370 Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
7371 because CHICKEN doesn't embed absolute references in compiled eggs.
7372 Test dependencies should go to @code{native-inputs}, as usual.
7375 @defvr {Scheme Variable} copy-build-system
7376 This variable is exported by @code{(guix build-system copy)}. It
7377 supports builds of simple packages that don't require much compiling,
7378 mostly just moving files around.
7380 It adds much of the @code{gnu-build-system} packages to the set of
7381 inputs. Because of this, the @code{copy-build-system} does not require
7382 all the boilerplate code often needed for the
7383 @code{trivial-build-system}.
7385 To further simplify the file installation process, an
7386 @code{#:install-plan} argument is exposed to let the packager specify
7387 which files go where. The install plan is a list of @code{(@var{source}
7388 @var{target} [@var{filters}])}. @var{filters} are optional.
7391 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
7393 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
7394 @item Otherwise install @var{source} as @var{target}.
7397 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
7398 the trailing slash of @var{target} is implied with the same meaning
7401 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
7402 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
7403 @code{#:exclude-regexp}, only select files are installed depending on
7404 the filters. Each filters is specified by a list of strings.
7406 @item With @code{#:include}, install all the files which the path suffix matches
7407 at least one of the elements in the given list.
7408 @item With @code{#:include-regexp}, install all the files which the
7409 subpaths match at least one of the regular expressions in the given
7411 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
7412 are the complement of their inclusion counterpart. Without @code{#:include} flags,
7413 install all files but those matching the exclusion filters.
7414 If both inclusions and exclusions are specified, the exclusions are done
7415 on top of the inclusions.
7418 In all cases, the paths relative to @var{source} are preserved within
7425 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
7426 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
7427 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
7428 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
7429 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
7430 @file{share/my-app/sub/file}.
7431 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
7432 @file{share/my-app/file}.
7437 @cindex Clojure (programming language)
7438 @cindex simple Clojure build system
7439 @defvr {Scheme Variable} clojure-build-system
7440 This variable is exported by @code{(guix build-system clojure)}. It implements
7441 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
7442 using plain old @code{compile} in Clojure. Cross-compilation is not supported
7445 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
7446 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
7447 @code{#:zip} parameters, respectively.
7449 A list of source directories, test directories and jar names can be specified
7450 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
7451 parameters, respectively. Compile directory and main class can be specified
7452 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
7453 Other parameters are documented below.
7455 This build system is an extension of @code{ant-build-system}, but with the
7456 following phases changed:
7461 This phase calls @code{compile} in Clojure to compile source files and runs
7462 @command{jar} to create jars from both source files and compiled files
7463 according to the include list and exclude list specified in
7464 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
7465 has priority over the include list. These lists consist of symbols
7466 representing Clojure libraries or the special keyword @code{#:all} representing
7467 all Clojure libraries found under the source directories. The parameter
7468 @code{#:omit-source?} decides if source should be included into the jars.
7471 This phase runs tests according to the include list and exclude list specified
7472 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
7473 meanings are analogous to that of @code{#:aot-include} and
7474 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
7475 stands for all Clojure libraries found under the test directories. The
7476 parameter @code{#:tests?} decides if tests should be run.
7479 This phase installs all jars built previously.
7482 Apart from the above, this build system also contains an additional phase:
7487 This phase installs all top-level files with base name matching
7488 @code{%doc-regex}. A different regex can be specified with the
7489 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
7490 directories specified in @code{#:doc-dirs} are installed as well.
7494 @defvr {Scheme Variable} cmake-build-system
7495 This variable is exported by @code{(guix build-system cmake)}. It
7496 implements the build procedure for packages using the
7497 @url{https://www.cmake.org, CMake build tool}.
7499 It automatically adds the @code{cmake} package to the set of inputs.
7500 Which package is used can be specified with the @code{#:cmake}
7503 The @code{#:configure-flags} parameter is taken as a list of flags
7504 passed to the @command{cmake} command. The @code{#:build-type}
7505 parameter specifies in abstract terms the flags passed to the compiler;
7506 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
7507 debugging information''), which roughly means that code is compiled with
7508 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
7511 @defvr {Scheme Variable} dune-build-system
7512 This variable is exported by @code{(guix build-system dune)}. It
7513 supports builds of packages using @uref{https://dune.build/, Dune}, a build
7514 tool for the OCaml programming language. It is implemented as an extension
7515 of the @code{ocaml-build-system} which is described below. As such, the
7516 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
7519 It automatically adds the @code{dune} package to the set of inputs.
7520 Which package is used can be specified with the @code{#:dune}
7523 There is no @code{configure} phase because dune packages typically don't
7524 need to be configured. The @code{#:build-flags} parameter is taken as a
7525 list of flags passed to the @code{dune} command during the build.
7527 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
7528 command instead of the more recent @code{dune} command while building
7529 a package. Its default value is @code{#f}.
7531 The @code{#:package} parameter can be passed to specify a package name, which
7532 is useful when a package contains multiple packages and you want to build
7533 only one of them. This is equivalent to passing the @code{-p} argument to
7537 @defvr {Scheme Variable} go-build-system
7538 This variable is exported by @code{(guix build-system go)}. It
7539 implements a build procedure for Go packages using the standard
7540 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
7541 Go build mechanisms}.
7543 The user is expected to provide a value for the key @code{#:import-path}
7544 and, in some cases, @code{#:unpack-path}. The
7545 @url{https://golang.org/doc/code.html#ImportPaths, import path}
7546 corresponds to the file system path expected by the package's build
7547 scripts and any referring packages, and provides a unique way to
7548 refer to a Go package. It is typically based on a combination of the
7549 package source code's remote URI and file system hierarchy structure. In
7550 some cases, you will need to unpack the package's source code to a
7551 different directory structure than the one indicated by the import path,
7552 and @code{#:unpack-path} should be used in such cases.
7554 Packages that provide Go libraries should install their source code into
7555 the built output. The key @code{#:install-source?}, which defaults to
7556 @code{#t}, controls whether or not the source code is installed. It can
7557 be set to @code{#f} for packages that only provide executable files.
7560 @defvr {Scheme Variable} glib-or-gtk-build-system
7561 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
7562 is intended for use with packages making use of GLib or GTK+.
7564 This build system adds the following two phases to the ones defined by
7565 @code{gnu-build-system}:
7568 @item glib-or-gtk-wrap
7569 The phase @code{glib-or-gtk-wrap} ensures that programs in
7570 @file{bin/} are able to find GLib ``schemas'' and
7571 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
7572 modules}. This is achieved by wrapping the programs in launch scripts
7573 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
7574 environment variables.
7576 It is possible to exclude specific package outputs from that wrapping
7577 process by listing their names in the
7578 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
7579 when an output is known not to contain any GLib or GTK+ binaries, and
7580 where wrapping would gratuitously add a dependency of that output on
7583 @item glib-or-gtk-compile-schemas
7584 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
7585 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
7586 GSettings schemas} of GLib are compiled. Compilation is performed by the
7587 @command{glib-compile-schemas} program. It is provided by the package
7588 @code{glib:bin} which is automatically imported by the build system.
7589 The @code{glib} package providing @command{glib-compile-schemas} can be
7590 specified with the @code{#:glib} parameter.
7593 Both phases are executed after the @code{install} phase.
7596 @defvr {Scheme Variable} guile-build-system
7597 This build system is for Guile packages that consist exclusively of Scheme
7598 code and that are so lean that they don't even have a makefile, let alone a
7599 @file{configure} script. It compiles Scheme code using @command{guild
7600 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
7601 installs the @file{.scm} and @file{.go} files in the right place. It also
7602 installs documentation.
7604 This build system supports cross-compilation by using the
7605 @option{--target} option of @samp{guild compile}.
7607 Packages built with @code{guile-build-system} must provide a Guile package in
7608 their @code{native-inputs} field.
7611 @defvr {Scheme Variable} julia-build-system
7612 This variable is exported by @code{(guix build-system julia)}. It
7613 implements the build procedure used by @uref{https://julialang.org/,
7614 julia} packages, which essentially is similar to running @samp{julia -e
7615 'using Pkg; Pkg.add(package)'} in an environment where
7616 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
7617 Tests are run with @code{Pkg.test}.
7619 Julia packages require the source @code{file-name} to be the real name of the
7620 package, correctly capitalized.
7622 For packages requiring shared library dependencies, you may need to write the
7623 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
7624 variable = /gnu/store/library.so} for each dependency, plus a void function
7625 @code{check_deps() = nothing}.
7627 Some older packages that aren't using @file{Package.toml} yet, will require
7628 this file to be created, too. The function @code{julia-create-package-toml}
7629 helps creating the file. You need to pass the outputs and the source of the
7630 package, it's name (the same as the @code{file-name} parameter), the package
7631 uuid, the package version, and a list of dependencies specified by their name
7635 @defvr {Scheme Variable} maven-build-system
7636 This variable is exported by @code{(guix build-system maven)}. It implements
7637 a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
7638 is a dependency and lifecycle management tool for Java. A user of Maven
7639 specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
7640 When Maven does not have one of the dependencies or plugins in its repository,
7641 it will download them and use them to build the package.
7643 The maven build system ensures that maven will not try to download any
7644 dependency by running in offline mode. Maven will fail if a dependency is
7645 missing. Before running Maven, the @file{pom.xml} (and subprojects) are
7646 modified to specify the version of dependencies and plugins that match the
7647 versions available in the guix build environment. Dependencies and plugins
7648 must be installed in the fake maven repository at @file{lib/m2}, and are
7649 symlinked into a proper repository before maven is run. Maven is instructed
7650 to use that repository for the build and installs built artifacts there.
7651 Changed files are copied to the @file{lib/m2} directory of the package output.
7653 You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
7654 or let the build system use the default @file{pom.xml} file in the sources.
7656 In case you need to specify a dependency's version manually, you can use the
7657 @code{#:local-packages} argument. It takes an association list where the key
7658 is the groupId of the package and its value is an association list where the
7659 key is the artifactId of the package and its value is the version you want to
7660 override in the @file{pom.xml}.
7662 Some packages use dependencies or plugins that are not useful at runtime nor
7663 at build time in Guix. You can alter the @file{pom.xml} file to remove them
7664 using the @code{#:exclude} argument. Its value is an association list where
7665 the key is the groupId of the plugin or dependency you want to remove, and
7666 the value is a list of artifactId you want to remove.
7668 You can override the default @code{jdk} and @code{maven} packages with the
7669 corresponding argument, @code{#:jdk} and @code{#:maven}.
7671 The @code{#:maven-plugins} argument is a list of maven plugins used during
7672 the build, with the same format as the @code{inputs} fields of the package
7673 declaration. Its default value is @code{(default-maven-plugins)} which is
7677 @defvr {Scheme Variable} minify-build-system
7678 This variable is exported by @code{(guix build-system minify)}. It
7679 implements a minification procedure for simple JavaScript packages.
7681 It adds @code{uglify-js} to the set of inputs and uses it to compress
7682 all JavaScript files in the @file{src} directory. A different minifier
7683 package can be specified with the @code{#:uglify-js} parameter, but it
7684 is expected that the package writes the minified code to the standard
7687 When the input JavaScript files are not all located in the @file{src}
7688 directory, the parameter @code{#:javascript-files} can be used to
7689 specify a list of file names to feed to the minifier.
7692 @defvr {Scheme Variable} ocaml-build-system
7693 This variable is exported by @code{(guix build-system ocaml)}. It implements
7694 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
7695 of choosing the correct set of commands to run for each package. OCaml
7696 packages can expect many different commands to be run. This build system will
7699 When the package has a @file{setup.ml} file present at the top-level, it will
7700 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
7701 @code{ocaml setup.ml -install}. The build system will assume that this file
7702 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
7703 care of setting the prefix and enabling tests if they are not disabled. You
7704 can pass configure and build flags with the @code{#:configure-flags} and
7705 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
7706 set of flags used to enable tests. The @code{#:use-make?} key can be used to
7707 bypass this system in the build and install phases.
7709 When the package has a @file{configure} file, it is assumed that it is a
7710 hand-made configure script that requires a different argument format than
7711 in the @code{gnu-build-system}. You can add more flags with the
7712 @code{#:configure-flags} key.
7714 When the package has a @file{Makefile} file (or @code{#:use-make?} is
7715 @code{#t}), it will be used and more flags can be passed to the build and
7716 install phases with the @code{#:make-flags} key.
7718 Finally, some packages do not have these files and use a somewhat standard
7719 location for its build system. In that case, the build system will run
7720 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
7721 providing the path to the required findlib module. Additional flags can
7722 be passed via the @code{#:build-flags} key. Install is taken care of by
7723 @command{opam-installer}. In this case, the @code{opam} package must
7724 be added to the @code{native-inputs} field of the package definition.
7726 Note that most OCaml packages assume they will be installed in the same
7727 directory as OCaml, which is not what we want in guix. In particular, they
7728 will install @file{.so} files in their module's directory, which is usually
7729 fine because it is in the OCaml compiler directory. In guix though, these
7730 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
7731 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
7732 @file{.so} libraries should be installed.
7735 @defvr {Scheme Variable} python-build-system
7736 This variable is exported by @code{(guix build-system python)}. It
7737 implements the more or less standard build procedure used by Python
7738 packages, which consists in running @code{python setup.py build} and
7739 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
7741 For packages that install stand-alone Python programs under @code{bin/},
7742 it takes care of wrapping these programs so that their @env{PYTHONPATH}
7743 environment variable points to all the Python libraries they depend on.
7745 Which Python package is used to perform the build can be specified with
7746 the @code{#:python} parameter. This is a useful way to force a package
7747 to be built for a specific version of the Python interpreter, which
7748 might be necessary if the package is only compatible with a single
7749 interpreter version.
7751 By default guix calls @code{setup.py} under control of
7752 @code{setuptools}, much like @command{pip} does. Some packages are not
7753 compatible with setuptools (and pip), thus you can disable this by
7754 setting the @code{#:use-setuptools?} parameter to @code{#f}.
7757 @defvr {Scheme Variable} perl-build-system
7758 This variable is exported by @code{(guix build-system perl)}. It
7759 implements the standard build procedure for Perl packages, which either
7760 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
7761 followed by @code{Build} and @code{Build install}; or in running
7762 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
7763 @code{make} and @code{make install}, depending on which of
7764 @code{Build.PL} or @code{Makefile.PL} is present in the package
7765 distribution. Preference is given to the former if both @code{Build.PL}
7766 and @code{Makefile.PL} exist in the package distribution. This
7767 preference can be reversed by specifying @code{#t} for the
7768 @code{#:make-maker?} parameter.
7770 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
7771 passes flags specified by the @code{#:make-maker-flags} or
7772 @code{#:module-build-flags} parameter, respectively.
7774 Which Perl package is used can be specified with @code{#:perl}.
7777 @defvr {Scheme Variable} qt-build-system
7778 This variable is exported by @code{(guix build-system qt)}. It
7779 is intended for use with applications using Qt or KDE.
7781 This build system adds the following two phases to the ones defined by
7782 @code{cmake-build-system}:
7786 The phase @code{check-setup} prepares the environment for running
7787 the checks as commonly used by Qt test programs.
7788 For now this only sets some environment variables:
7789 @code{QT_QPA_PLATFORM=offscreen},
7790 @code{DBUS_FATAL_WARNINGS=0} and
7791 @code{CTEST_OUTPUT_ON_FAILURE=1}.
7793 This phase is added before the @code{check} phase.
7794 It's a separate phase to ease adjusting if necessary.
7797 The phase @code{qt-wrap}
7798 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
7799 and output. In case some path is found, all programs in the output's
7800 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
7801 are wrapped in scripts defining the necessary environment variables.
7803 It is possible to exclude specific package outputs from that wrapping process
7804 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
7805 This is useful when an output is known not to contain any Qt binaries, and
7806 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
7809 This phase is added after the @code{install} phase.
7813 @defvr {Scheme Variable} r-build-system
7814 This variable is exported by @code{(guix build-system r)}. It
7815 implements the build procedure used by @uref{https://r-project.org, R}
7816 packages, which essentially is little more than running @samp{R CMD
7817 INSTALL --library=/gnu/store/@dots{}} in an environment where
7818 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
7819 run after installation using the R function
7820 @code{tools::testInstalledPackage}.
7823 @defvr {Scheme Variable} rakudo-build-system
7824 This variable is exported by @code{(guix build-system rakudo)}. It
7825 implements the build procedure used by @uref{https://rakudo.org/,
7826 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
7827 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
7828 installs the binaries, library files and the resources, as well as wrap
7829 the files under the @code{bin/} directory. Tests can be skipped by
7830 passing @code{#f} to the @code{tests?} parameter.
7832 Which rakudo package is used can be specified with @code{rakudo}.
7833 Which perl6-tap-harness package used for the tests can be specified with
7834 @code{#:prove6} or removed by passing @code{#f} to the
7835 @code{with-prove6?} parameter.
7836 Which perl6-zef package used for tests and installing can be specified
7837 with @code{#:zef} or removed by passing @code{#f} to the
7838 @code{with-zef?} parameter.
7841 @defvr {Scheme Variable} texlive-build-system
7842 This variable is exported by @code{(guix build-system texlive)}. It is
7843 used to build TeX packages in batch mode with a specified engine. The
7844 build system sets the @env{TEXINPUTS} variable to find all TeX source
7845 files in the inputs.
7847 By default it runs @code{luatex} on all files ending on @code{ins}. A
7848 different engine and format can be specified with the
7849 @code{#:tex-format} argument. Different build targets can be specified
7850 with the @code{#:build-targets} argument, which expects a list of file
7851 names. The build system adds only @code{texlive-bin} and
7852 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
7853 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
7854 and @code{#:texlive-latex-base}, respectively.
7856 The @code{#:tex-directory} parameter tells the build system where to
7857 install the built files under the texmf tree.
7860 @defvr {Scheme Variable} ruby-build-system
7861 This variable is exported by @code{(guix build-system ruby)}. It
7862 implements the RubyGems build procedure used by Ruby packages, which
7863 involves running @code{gem build} followed by @code{gem install}.
7865 The @code{source} field of a package that uses this build system
7866 typically references a gem archive, since this is the format that Ruby
7867 developers use when releasing their software. The build system unpacks
7868 the gem archive, potentially patches the source, runs the test suite,
7869 repackages the gem, and installs it. Additionally, directories and
7870 tarballs may be referenced to allow building unreleased gems from Git or
7871 a traditional source release tarball.
7873 Which Ruby package is used can be specified with the @code{#:ruby}
7874 parameter. A list of additional flags to be passed to the @command{gem}
7875 command can be specified with the @code{#:gem-flags} parameter.
7878 @defvr {Scheme Variable} waf-build-system
7879 This variable is exported by @code{(guix build-system waf)}. It
7880 implements a build procedure around the @code{waf} script. The common
7881 phases---@code{configure}, @code{build}, and @code{install}---are
7882 implemented by passing their names as arguments to the @code{waf}
7885 The @code{waf} script is executed by the Python interpreter. Which
7886 Python package is used to run the script can be specified with the
7887 @code{#:python} parameter.
7890 @defvr {Scheme Variable} scons-build-system
7891 This variable is exported by @code{(guix build-system scons)}. It
7892 implements the build procedure used by the SCons software construction
7893 tool. This build system runs @code{scons} to build the package,
7894 @code{scons test} to run tests, and then @code{scons install} to install
7897 Additional flags to be passed to @code{scons} can be specified with the
7898 @code{#:scons-flags} parameter. The default build and install targets
7899 can be overridden with @code{#:build-targets} and
7900 @code{#:install-targets} respectively. The version of Python used to
7901 run SCons can be specified by selecting the appropriate SCons package
7902 with the @code{#:scons} parameter.
7905 @defvr {Scheme Variable} haskell-build-system
7906 This variable is exported by @code{(guix build-system haskell)}. It
7907 implements the Cabal build procedure used by Haskell packages, which
7908 involves running @code{runhaskell Setup.hs configure
7909 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
7910 Instead of installing the package by running @code{runhaskell Setup.hs
7911 install}, to avoid trying to register libraries in the read-only
7912 compiler store directory, the build system uses @code{runhaskell
7913 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
7914 addition, the build system generates the package documentation by
7915 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
7916 is passed. Optional Haddock parameters can be passed with the help of
7917 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
7918 not found, the build system looks for @code{Setup.lhs} instead.
7920 Which Haskell compiler is used can be specified with the @code{#:haskell}
7921 parameter which defaults to @code{ghc}.
7924 @defvr {Scheme Variable} dub-build-system
7925 This variable is exported by @code{(guix build-system dub)}. It
7926 implements the Dub build procedure used by D packages, which
7927 involves running @code{dub build} and @code{dub run}.
7928 Installation is done by copying the files manually.
7930 Which D compiler is used can be specified with the @code{#:ldc}
7931 parameter which defaults to @code{ldc}.
7934 @anchor{emacs-build-system}
7935 @defvr {Scheme Variable} emacs-build-system
7936 This variable is exported by @code{(guix build-system emacs)}. It
7937 implements an installation procedure similar to the packaging system
7938 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
7940 It first creates the @code{@code{package}-autoloads.el} file, then it
7941 byte compiles all Emacs Lisp files. Differently from the Emacs
7942 packaging system, the Info documentation files are moved to the standard
7943 documentation directory and the @file{dir} file is deleted. The Elisp
7944 package files are installed directly under @file{share/emacs/site-lisp}.
7947 @defvr {Scheme Variable} font-build-system
7948 This variable is exported by @code{(guix build-system font)}. It
7949 implements an installation procedure for font packages where upstream
7950 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
7951 need to be copied into place. It copies font files to standard
7952 locations in the output directory.
7955 @defvr {Scheme Variable} meson-build-system
7956 This variable is exported by @code{(guix build-system meson)}. It
7957 implements the build procedure for packages that use
7958 @url{https://mesonbuild.com, Meson} as their build system.
7960 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
7961 of inputs, and they can be changed with the parameters @code{#:meson}
7962 and @code{#:ninja} if needed. The default Meson is
7963 @code{meson-for-build}, which is special because it doesn't clear the
7964 @code{RUNPATH} of binaries and libraries when they are installed.
7966 This build system is an extension of @code{gnu-build-system}, but with the
7967 following phases changed to some specific for Meson:
7972 The phase runs @code{meson} with the flags specified in
7973 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
7974 @code{debugoptimized} unless something else is specified in
7975 @code{#:build-type}.
7978 The phase runs @code{ninja} to build the package in parallel by default, but
7979 this can be changed with @code{#:parallel-build?}.
7982 The phase runs @code{ninja} with the target specified in @code{#:test-target},
7983 which is @code{"test"} by default.
7986 The phase runs @code{ninja install} and can not be changed.
7989 Apart from that, the build system also adds the following phases:
7994 This phase ensures that all binaries can find the libraries they need.
7995 It searches for required libraries in subdirectories of the package being
7996 built, and adds those to @code{RUNPATH} where needed. It also removes
7997 references to libraries left over from the build phase by
7998 @code{meson-for-build}, such as test dependencies, that aren't actually
7999 required for the program to run.
8001 @item glib-or-gtk-wrap
8002 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
8003 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
8005 @item glib-or-gtk-compile-schemas
8006 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
8007 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
8011 @defvr {Scheme Variable} linux-module-build-system
8012 @code{linux-module-build-system} allows building Linux kernel modules.
8014 @cindex build phases
8015 This build system is an extension of @code{gnu-build-system}, but with the
8016 following phases changed:
8021 This phase configures the environment so that the Linux kernel's Makefile
8022 can be used to build the external kernel module.
8025 This phase uses the Linux kernel's Makefile in order to build the external
8029 This phase uses the Linux kernel's Makefile in order to install the external
8033 It is possible and useful to specify the Linux kernel to use for building
8034 the module (in the @code{arguments} form of a package using the
8035 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
8038 @defvr {Scheme Variable} node-build-system
8039 This variable is exported by @code{(guix build-system node)}. It
8040 implements the build procedure used by @uref{https://nodejs.org,
8041 Node.js}, which implements an approximation of the @code{npm install}
8042 command, followed by an @code{npm test} command.
8044 Which Node.js package is used to interpret the @code{npm} commands can
8045 be specified with the @code{#:node} parameter which defaults to
8049 Lastly, for packages that do not need anything as sophisticated, a
8050 ``trivial'' build system is provided. It is trivial in the sense that
8051 it provides basically no support: it does not pull any implicit inputs,
8052 and does not have a notion of build phases.
8054 @defvr {Scheme Variable} trivial-build-system
8055 This variable is exported by @code{(guix build-system trivial)}.
8057 This build system requires a @code{#:builder} argument. This argument
8058 must be a Scheme expression that builds the package output(s)---as
8059 with @code{build-expression->derivation} (@pxref{Derivations,
8060 @code{build-expression->derivation}}).
8064 @section Build Phases
8066 @cindex build phases, for packages
8067 Almost all package build systems implement a notion @dfn{build phases}:
8068 a sequence of actions that the build system executes, when you build the
8069 package, leading to the installed byproducts in the store. A notable
8070 exception is the ``bare-bones'' @code{trivial-build-system}
8071 (@pxref{Build Systems}).
8073 As discussed in the previous section, those build systems provide a
8074 standard list of phases. For @code{gnu-build-system}, the standard
8075 phases include an @code{unpack} phase to unpack the source code tarball,
8076 a @command{configure} phase to run @code{./configure}, a @code{build}
8077 phase to run @command{make}, and (among others) an @code{install} phase
8078 to run @command{make install}; @pxref{Build Systems}, for a more
8079 detailed view of these phases. Likewise, @code{cmake-build-system}
8080 inherits these phases, but its @code{configure} phase runs
8081 @command{cmake} instead of @command{./configure}. Other build systems,
8082 such as @code{python-build-system}, have a wholly different list of
8083 standard phases. All this code runs on the @dfn{build side}: it is
8084 evaluated when you actually build the package, in a dedicated build
8085 process spawned by the build daemon (@pxref{Invoking guix-daemon}).
8087 Build phases are represented as association lists or ``alists''
8088 (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
8089 each key is a symbol for the name of the phase and the associated value
8090 is a procedure that accepts an arbitrary number of arguments. By
8091 convention, those procedures receive information about the build in the
8092 form of @dfn{keyword parameters}, which they can use or ignore.
8094 For example, here is how @code{(guix build gnu-build-system)} defines
8095 @code{%standard-phases}, the variable holding its alist of build
8096 phases@footnote{We present a simplified view of those build phases, but
8097 do take a look at @code{(guix build gnu-build-system)} to see all the
8101 ;; The build phases of 'gnu-build-system'.
8103 (define* (unpack #:key source #:allow-other-keys)
8104 ;; Extract the source tarball.
8105 (invoke "tar" "xvf" source))
8107 (define* (configure #:key outputs #:allow-other-keys)
8108 ;; Run the 'configure' script. Install to output "out".
8109 (let ((out (assoc-ref outputs "out")))
8110 (invoke "./configure"
8111 (string-append "--prefix=" out))))
8113 (define* (build #:allow-other-keys)
8117 (define* (check #:key (test-target "check") (tests? #true)
8119 ;; Run the test suite.
8121 (invoke "make" test-target)
8122 (display "test suite not run\n")))
8124 (define* (install #:allow-other-keys)
8125 ;; Install files to the prefix 'configure' specified.
8126 (invoke "make" "install"))
8128 (define %standard-phases
8129 ;; The list of standard phases (quite a few are omitted
8130 ;; for brevity). Each element is a symbol/procedure pair.
8131 (list (cons 'unpack unpack)
8132 (cons 'configure configure)
8135 (cons 'install install)))
8138 This shows how @code{%standard-phases} is defined as a list of
8139 symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
8140 Manual}). The first pair associates the @code{unpack} procedure with
8141 the @code{unpack} symbol---a name; the second pair defines the
8142 @code{configure} phase similarly, and so on. When building a package
8143 that uses @code{gnu-build-system} with its default list of phases, those
8144 phases are executed sequentially. You can see the name of each phase
8145 started and completed in the build log of packages that you build.
8147 Let's now look at the procedures themselves. Each one is defined with
8148 @code{define*}: @code{#:key} lists keyword parameters the procedure
8149 accepts, possibly with a default value, and @code{#:allow-other-keys}
8150 specifies that other keyword parameters are ignored (@pxref{Optional
8151 Arguments,,, guile, GNU Guile Reference Manual}).
8153 The @code{unpack} procedure honors the @code{source} parameter, which
8154 the build system uses to pass the file name of the source tarball (or
8155 version control checkout), and it ignores other parameters. The
8156 @code{configure} phase only cares about the @code{outputs} parameter, an
8157 alist mapping package output names to their store file name
8158 (@pxref{Packages with Multiple Outputs}). It extracts the file name of
8159 for @code{out}, the default output, and passes it to
8160 @command{./configure} as the installation prefix, meaning that
8161 @command{make install} will eventually copy all the files in that
8162 directory (@pxref{Configuration, configuration and makefile
8163 conventions,, standards, GNU Coding Standards}). @code{build} and
8164 @code{install} ignore all their arguments. @code{check} honors the
8165 @code{test-target} argument, which specifies the name of the Makefile
8166 target to run tests; it prints a message and skips tests when
8167 @code{tests?} is false.
8169 @cindex build phases, customizing
8170 The list of phases used for a particular package can be changed with the
8171 @code{#:phases} parameter of the build system. Changing the set of
8172 build phases boils down to building a new alist of phases based on the
8173 @code{%standard-phases} alist described above. This can be done with
8174 standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
8175 Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
8176 more convenient to do so with @code{modify-phases} (@pxref{Build
8177 Utilities, @code{modify-phases}}).
8179 Here is an example of a package definition that removes the
8180 @code{configure} phase of @code{%standard-phases} and inserts a new
8181 phase before the @code{build} phase, called
8182 @code{set-prefix-in-makefile}:
8185 (define-public example
8188 ;; other fields omitted
8189 (build-system gnu-build-system)
8191 '(#:phases (modify-phases %standard-phases
8193 (add-before 'build 'set-prefix-in-makefile
8194 (lambda* (#:key outputs #:allow-other-keys)
8195 ;; Modify the makefile so that its
8196 ;; 'PREFIX' variable points to "out".
8197 (let ((out (assoc-ref outputs "out")))
8198 (substitute* "Makefile"
8200 (string-append "PREFIX = "
8205 The new phase that is inserted is written as an anonymous procedure,
8206 introduced with @code{lambda*}; it honors the @code{outputs} parameter
8207 we have seen before. @xref{Build Utilities}, for more about the helpers
8208 used by this phase, and for more examples of @code{modify-phases}.
8210 @cindex code staging
8211 @cindex staging, of code
8212 Keep in mind that build phases are code evaluated at the time the
8213 package is actually built. This explains why the whole
8214 @code{modify-phases} expression above is quoted (it comes after the
8215 @code{'} or apostrophe): it is @dfn{staged} for later execution.
8216 @xref{G-Expressions}, for an explanation of code staging and the
8217 @dfn{code strata} involved.
8219 @node Build Utilities
8220 @section Build Utilities
8222 As soon as you start writing non-trivial package definitions
8223 (@pxref{Defining Packages}) or other build actions
8224 (@pxref{G-Expressions}), you will likely start looking for helpers for
8225 ``shell-like'' actions---creating directories, copying and deleting
8226 files recursively, manipulating build phases, and so on. The
8227 @code{(guix build utils)} module provides such utility procedures.
8229 Most build systems load @code{(guix build utils)} (@pxref{Build
8230 Systems}). Thus, when writing custom build phases for your package
8231 definitions, you can usually assume those procedures are in scope.
8233 When writing G-expressions, you can import @code{(guix build utils)} on
8234 the ``build side'' using @code{with-imported-modules} and then put it in
8235 scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
8236 guile, GNU Guile Reference Manual}):
8239 (with-imported-modules '((guix build utils)) ;import it
8240 (computed-file "empty-tree"
8243 (use-modules (guix build utils))
8245 ;; Happily use its 'mkdir-p' procedure.
8246 (mkdir-p (string-append #$output "/a/b/c")))))
8249 The remainder of this section is the reference for most of the utility
8250 procedures provided by @code{(guix build utils)}.
8252 @c TODO Document what's missing.
8254 @subsection Dealing with Store File Names
8256 This section documents procedures that deal with store file names.
8258 @deffn {Scheme Procedure} %store-directory
8259 Return the directory name of the store.
8262 @deffn {Scheme Procedure} store-file-name? @var{file}
8263 Return true if @var{file} is in the store.
8266 @deffn {Scheme Procedure} strip-store-file-name @var{file}
8267 Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
8268 The result is typically a @code{"@var{package}-@var{version}"} string.
8271 @deffn {Scheme Procedure} package-name->name+version @var{name}
8272 Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
8273 values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
8274 unavailable, @var{name} and @code{#f} are returned. The first hyphen
8275 followed by a digit is considered to introduce the version part.
8278 @subsection File Types
8280 The procedures below deal with files and file types.
8282 @deffn {Scheme Procedure} directory-exists? @var{dir}
8283 Return @code{#t} if @var{dir} exists and is a directory.
8286 @deffn {Scheme Procedure} executable-file? @var{file}
8287 Return @code{#t} if @var{file} exists and is executable.
8290 @deffn {Scheme Procedure} symbolic-link? @var{file}
8291 Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
8294 @deffn {Scheme Procedure} elf-file? @var{file}
8295 @deffnx {Scheme Procedure} ar-file? @var{file}
8296 @deffnx {Scheme Procedure} gzip-file? @var{file}
8297 Return @code{#t} if @var{file} is, respectively, an ELF file, an
8298 @code{ar} archive (such as a @file{.a} static library), or a gzip file.
8301 @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
8302 If @var{file} is a gzip file, reset its embedded timestamp (as with
8303 @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
8304 When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
8307 @subsection File Manipulation
8309 The following procedures and macros help create, modify, and delete
8310 files. They provide functionality comparable to common shell utilities
8311 such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
8312 @command{sed}. They complement Guile's extensive, but low-level, file
8313 system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
8315 @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
8316 Run @var{body} with @var{directory} as the process's current directory.
8318 Essentially, this macro changes the current directory to @var{directory}
8319 before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
8320 guile, GNU Guile Reference Manual}). It changes back to the initial
8321 directory when the dynamic extent of @var{body} is left, be it @i{via}
8322 normal procedure return or @i{via} a non-local exit such as an
8326 @deffn {Scheme Procedure} mkdir-p @var{dir}
8327 Create directory @var{dir} and all its ancestors.
8330 @deffn {Scheme Procedure} install-file @var{file} @var{directory}
8331 Create @var{directory} if it does not exist and copy @var{file} in there
8332 under the same name.
8335 @deffn {Scheme Procedure} make-file-writable @var{file}
8336 Make @var{file} writable for its owner.
8339 @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
8340 [#:log (current-output-port)] [#:follow-symlinks? #f] [#:keep-mtime? #f]
8341 Copy @var{source} directory to @var{destination}. Follow symlinks if
8342 @var{follow-symlinks?} is true; otherwise, just preserve them. When
8343 @var{keep-mtime?} is true, keep the modification time of the files in
8344 @var{source} on those of @var{destination}. Write verbose output to the
8348 @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
8349 [#:follow-mounts? #f]
8350 Delete @var{dir} recursively, like @command{rm -rf}, without following
8351 symlinks. Don't follow mount points either, unless @var{follow-mounts?}
8352 is true. Report but ignore errors.
8355 @deffn {Scheme Syntax} substitute* @var{file} @
8356 ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
8357 Substitute @var{regexp} in @var{file} by the string returned by
8358 @var{body}. @var{body} is evaluated with each @var{match-var} bound to
8359 the corresponding positional regexp sub-expression. For example:
8365 (("foo([a-z]+)bar(.*)$" all letters end)
8366 (string-append "baz" letter end)))
8369 Here, anytime a line of @var{file} contains @code{hello}, it is replaced
8370 by @code{good morning}. Anytime a line of @var{file} matches the second
8371 regexp, @code{all} is bound to the complete match, @code{letters} is bound
8372 to the first sub-expression, and @code{end} is bound to the last one.
8374 When one of the @var{match-var} is @code{_}, no variable is bound to the
8375 corresponding match substring.
8377 Alternatively, @var{file} may be a list of file names, in which case
8378 they are all subject to the substitutions.
8380 Be careful about using @code{$} to match the end of a line; by itself it
8381 won't match the terminating newline of a line.
8384 @subsection File Search
8386 @cindex file, searching
8387 This section documents procedures to search and filter files.
8389 @deffn {Scheme Procedure} file-name-predicate @var{regexp}
8390 Return a predicate that returns true when passed a file name whose base
8391 name matches @var{regexp}.
8394 @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
8395 [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
8396 Return the lexicographically sorted list of files under @var{dir} for
8397 which @var{pred} returns true. @var{pred} is passed two arguments: the
8398 absolute file name, and its stat buffer; the default predicate always
8399 returns true. @var{pred} can also be a regular expression, in which
8400 case it is equivalent to @code{(file-name-predicate @var{pred})}.
8401 @var{stat} is used to obtain file information; using @code{lstat} means
8402 that symlinks are not followed. If @var{directories?} is true, then
8403 directories will also be included. If @var{fail-on-error?} is true,
8404 raise an exception upon error.
8407 Here are a few examples where we assume that the current directory is
8408 the root of the Guix source tree:
8411 ;; List all the regular files in the current directory.
8413 @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
8415 ;; List all the .scm files under gnu/services.
8416 (find-files "gnu/services" "\\.scm$")
8417 @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
8419 ;; List ar files in the current directory.
8420 (find-files "." (lambda (file stat) (ar-file? file)))
8421 @result{} ("./libformat.a" "./libstore.a" @dots{})
8424 @deffn {Scheme Procedure} which @var{program}
8425 Return the complete file name for @var{program} as found in
8426 @code{$PATH}, or @code{#f} if @var{program} could not be found.
8429 @subsection Build Phases
8431 @cindex build phases
8432 The @code{(guix build utils)} also contains tools to manipulate build
8433 phases as used by build systems (@pxref{Build Systems}). Build phases
8434 are represented as association lists or ``alists'' (@pxref{Association
8435 Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
8436 naming the phase and the associated value is a procedure (@pxref{Build
8439 Guile core and the @code{(srfi srfi-1)} module both provide tools to
8440 manipulate alists. The @code{(guix build utils)} module complements
8441 those with tools written with build phases in mind.
8443 @cindex build phases, modifying
8444 @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
8445 Modify @var{phases} sequentially as per each @var{clause}, which may
8446 have one of the following forms:
8449 (delete @var{old-phase-name})
8450 (replace @var{old-phase-name} @var{new-phase})
8451 (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
8452 (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
8455 Where every @var{phase-name} above is an expression evaluating to a
8456 symbol, and @var{new-phase} an expression evaluating to a procedure.
8459 The example below is taken from the definition of the @code{grep}
8460 package. It adds a phase to run after the @code{install} phase, called
8461 @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
8462 is for anonymous procedures) that takes a @code{#:outputs} keyword
8463 argument and ignores extra keyword arguments (@pxref{Optional
8464 Arguments,,, guile, GNU Guile Reference Manual}, for more on
8465 @code{lambda*} and optional and keyword arguments.) The phase uses
8466 @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
8467 scripts so that they refer to @code{grep} by its absolute file name:
8470 (modify-phases %standard-phases
8471 (add-after 'install 'fix-egrep-and-fgrep
8472 ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
8473 ;; absolute file name instead of searching for it in $PATH.
8474 (lambda* (#:key outputs #:allow-other-keys)
8475 (let* ((out (assoc-ref outputs "out"))
8476 (bin (string-append out "/bin")))
8477 (substitute* (list (string-append bin "/egrep")
8478 (string-append bin "/fgrep"))
8480 (string-append "exec " bin "/grep")))
8484 In the example below, phases are modified in two ways: the standard
8485 @code{configure} phase is deleted, presumably because the package does
8486 not have a @file{configure} script or anything similar, and the default
8487 @code{install} phase is replaced by one that manually copies the
8488 executable files to be installed:
8491 (modify-phases %standard-phases
8492 (delete 'configure) ;no 'configure' script
8494 (lambda* (#:key outputs #:allow-other-keys)
8495 ;; The package's Makefile doesn't provide an "install"
8496 ;; rule so do it by ourselves.
8497 (let ((bin (string-append (assoc-ref outputs "out")
8499 (install-file "footswitch" bin)
8500 (install-file "scythe" bin)
8504 @c TODO: Add more examples.
8513 Conceptually, the @dfn{store} is the place where derivations that have
8514 been built successfully are stored---by default, @file{/gnu/store}.
8515 Sub-directories in the store are referred to as @dfn{store items} or
8516 sometimes @dfn{store paths}. The store has an associated database that
8517 contains information such as the store paths referred to by each store
8518 path, and the list of @emph{valid} store items---results of successful
8519 builds. This database resides in @file{@var{localstatedir}/guix/db},
8520 where @var{localstatedir} is the state directory specified @i{via}
8521 @option{--localstatedir} at configure time, usually @file{/var}.
8523 The store is @emph{always} accessed by the daemon on behalf of its clients
8524 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
8525 connect to the daemon over a Unix-domain socket, send requests to it,
8526 and read the result---these are remote procedure calls, or RPCs.
8529 Users must @emph{never} modify files under @file{/gnu/store} directly.
8530 This would lead to inconsistencies and break the immutability
8531 assumptions of Guix's functional model (@pxref{Introduction}).
8533 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
8534 how to check the integrity of the store and attempt recovery from
8535 accidental modifications.
8538 The @code{(guix store)} module provides procedures to connect to the
8539 daemon, and to perform RPCs. These are described below. By default,
8540 @code{open-connection}, and thus all the @command{guix} commands,
8541 connect to the local daemon or to the URI specified by the
8542 @env{GUIX_DAEMON_SOCKET} environment variable.
8544 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
8545 When set, the value of this variable should be a file name or a URI
8546 designating the daemon endpoint. When it is a file name, it denotes a
8547 Unix-domain socket to connect to. In addition to file names, the
8548 supported URI schemes are:
8553 These are for Unix-domain sockets.
8554 @code{file:///var/guix/daemon-socket/socket} is equivalent to
8555 @file{/var/guix/daemon-socket/socket}.
8558 @cindex daemon, remote access
8559 @cindex remote access to the daemon
8560 @cindex daemon, cluster setup
8561 @cindex clusters, daemon setup
8562 These URIs denote connections over TCP/IP, without encryption nor
8563 authentication of the remote host. The URI must specify the host name
8564 and optionally a port number (by default port 44146 is used):
8567 guix://master.guix.example.org:1234
8570 This setup is suitable on local networks, such as clusters, where only
8571 trusted nodes may connect to the build daemon at
8572 @code{master.guix.example.org}.
8574 The @option{--listen} option of @command{guix-daemon} can be used to
8575 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
8576 @option{--listen}}).
8579 @cindex SSH access to build daemons
8580 These URIs allow you to connect to a remote daemon over SSH. This
8581 feature requires Guile-SSH (@pxref{Requirements}) and a working
8582 @command{guile} binary in @env{PATH} on the destination machine. It
8583 supports public key and GSSAPI authentication. A typical URL might look
8587 ssh://charlie@@guix.example.org:22
8590 As for @command{guix copy}, the usual OpenSSH client configuration files
8591 are honored (@pxref{Invoking guix copy}).
8594 Additional URI schemes may be supported in the future.
8596 @c XXX: Remove this note when the protocol incurs fewer round trips
8597 @c and when (guix derivations) no longer relies on file system access.
8599 The ability to connect to remote build daemons is considered
8600 experimental as of @value{VERSION}. Please get in touch with us to
8601 share any problems or suggestions you may have (@pxref{Contributing}).
8605 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
8606 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
8607 @var{reserve-space?} is true, instruct it to reserve a little bit of
8608 extra space on the file system so that the garbage collector can still
8609 operate should the disk become full. Return a server object.
8611 @var{file} defaults to @code{%default-socket-path}, which is the normal
8612 location given the options that were passed to @command{configure}.
8615 @deffn {Scheme Procedure} close-connection @var{server}
8616 Close the connection to @var{server}.
8619 @defvr {Scheme Variable} current-build-output-port
8620 This variable is bound to a SRFI-39 parameter, which refers to the port
8621 where build and error logs sent by the daemon should be written.
8624 Procedures that make RPCs all take a server object as their first
8627 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
8628 @cindex invalid store items
8629 Return @code{#t} when @var{path} designates a valid store item and
8630 @code{#f} otherwise (an invalid item may exist on disk but still be
8631 invalid, for instance because it is the result of an aborted or failed
8634 A @code{&store-protocol-error} condition is raised if @var{path} is not
8635 prefixed by the store directory (@file{/gnu/store}).
8638 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
8639 Add @var{text} under file @var{name} in the store, and return its store
8640 path. @var{references} is the list of store paths referred to by the
8641 resulting store path.
8644 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
8646 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
8647 file names, or derivation/output pairs, using the specified
8648 @var{mode}---@code{(build-mode normal)} by default.
8651 Note that the @code{(guix monads)} module provides a monad as well as
8652 monadic versions of the above procedures, with the goal of making it
8653 more convenient to work with code that accesses the store (@pxref{The
8657 @i{This section is currently incomplete.}
8660 @section Derivations
8663 Low-level build actions and the environment in which they are performed
8664 are represented by @dfn{derivations}. A derivation contains the
8665 following pieces of information:
8669 The outputs of the derivation---derivations produce at least one file or
8670 directory in the store, but may produce more.
8673 @cindex build-time dependencies
8674 @cindex dependencies, build-time
8675 The inputs of the derivations---i.e., its build-time dependencies---which may
8676 be other derivations or plain files in the store (patches, build scripts,
8680 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
8683 The file name of a build script in the store, along with the arguments
8687 A list of environment variables to be defined.
8691 @cindex derivation path
8692 Derivations allow clients of the daemon to communicate build actions to
8693 the store. They exist in two forms: as an in-memory representation,
8694 both on the client- and daemon-side, and as files in the store whose
8695 name end in @file{.drv}---these files are referred to as @dfn{derivation
8696 paths}. Derivations paths can be passed to the @code{build-derivations}
8697 procedure to perform the build actions they prescribe (@pxref{The
8700 @cindex fixed-output derivations
8701 Operations such as file downloads and version-control checkouts for
8702 which the expected content hash is known in advance are modeled as
8703 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
8704 of a fixed-output derivation are independent of its inputs---e.g., a
8705 source code download produces the same result regardless of the download
8706 method and tools being used.
8709 @cindex run-time dependencies
8710 @cindex dependencies, run-time
8711 The outputs of derivations---i.e., the build results---have a set of
8712 @dfn{references}, as reported by the @code{references} RPC or the
8713 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
8714 are the set of run-time dependencies of the build results. References are a
8715 subset of the inputs of the derivation; this subset is automatically computed
8716 by the build daemon by scanning all the files in the outputs.
8718 The @code{(guix derivations)} module provides a representation of
8719 derivations as Scheme objects, along with procedures to create and
8720 otherwise manipulate derivations. The lowest-level primitive to create
8721 a derivation is the @code{derivation} procedure:
8723 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
8724 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
8725 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
8726 [#:system (%current-system)] [#:references-graphs #f] @
8727 [#:allowed-references #f] [#:disallowed-references #f] @
8728 [#:leaked-env-vars #f] [#:local-build? #f] @
8729 [#:substitutable? #t] [#:properties '()]
8730 Build a derivation with the given arguments, and return the resulting
8731 @code{<derivation>} object.
8733 When @var{hash} and @var{hash-algo} are given, a
8734 @dfn{fixed-output derivation} is created---i.e., one whose result is
8735 known in advance, such as a file download. If, in addition,
8736 @var{recursive?} is true, then that fixed output may be an executable
8737 file or a directory and @var{hash} must be the hash of an archive
8738 containing this output.
8740 When @var{references-graphs} is true, it must be a list of file
8741 name/store path pairs. In that case, the reference graph of each store
8742 path is exported in the build environment in the corresponding file, in
8743 a simple text format.
8745 When @var{allowed-references} is true, it must be a list of store items
8746 or outputs that the derivation's output may refer to. Likewise,
8747 @var{disallowed-references}, if true, must be a list of things the
8748 outputs may @emph{not} refer to.
8750 When @var{leaked-env-vars} is true, it must be a list of strings
8751 denoting environment variables that are allowed to ``leak'' from the
8752 daemon's environment to the build environment. This is only applicable
8753 to fixed-output derivations---i.e., when @var{hash} is true. The main
8754 use is to allow variables such as @code{http_proxy} to be passed to
8755 derivations that download files.
8757 When @var{local-build?} is true, declare that the derivation is not a
8758 good candidate for offloading and should rather be built locally
8759 (@pxref{Daemon Offload Setup}). This is the case for small derivations
8760 where the costs of data transfers would outweigh the benefits.
8762 When @var{substitutable?} is false, declare that substitutes of the
8763 derivation's output should not be used (@pxref{Substitutes}). This is
8764 useful, for instance, when building packages that capture details of the
8765 host CPU instruction set.
8767 @var{properties} must be an association list describing ``properties'' of the
8768 derivation. It is kept as-is, uninterpreted, in the derivation.
8772 Here's an example with a shell script as its builder, assuming
8773 @var{store} is an open connection to the daemon, and @var{bash} points
8774 to a Bash executable in the store:
8777 (use-modules (guix utils)
8781 (let ((builder ; add the Bash script to the store
8782 (add-text-to-store store "my-builder.sh"
8783 "echo hello world > $out\n" '())))
8784 (derivation store "foo"
8785 bash `("-e" ,builder)
8786 #:inputs `((,bash) (,builder))
8787 #:env-vars '(("HOME" . "/homeless"))))
8788 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
8791 As can be guessed, this primitive is cumbersome to use directly. A
8792 better approach is to write build scripts in Scheme, of course! The
8793 best course of action for that is to write the build code as a
8794 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
8795 information, @pxref{G-Expressions}.
8797 Once upon a time, @code{gexp->derivation} did not exist and constructing
8798 derivations with build code written in Scheme was achieved with
8799 @code{build-expression->derivation}, documented below. This procedure
8800 is now deprecated in favor of the much nicer @code{gexp->derivation}.
8802 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
8803 @var{name} @var{exp} @
8804 [#:system (%current-system)] [#:inputs '()] @
8805 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
8806 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
8807 [#:references-graphs #f] [#:allowed-references #f] @
8808 [#:disallowed-references #f] @
8809 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
8810 Return a derivation that executes Scheme expression @var{exp} as a
8811 builder for derivation @var{name}. @var{inputs} must be a list of
8812 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
8813 @code{"out"} is assumed. @var{modules} is a list of names of Guile
8814 modules from the current search path to be copied in the store,
8815 compiled, and made available in the load path during the execution of
8816 @var{exp}---e.g., @code{((guix build utils) (guix build
8817 gnu-build-system))}.
8819 @var{exp} is evaluated in an environment where @code{%outputs} is bound
8820 to a list of output/path pairs, and where @code{%build-inputs} is bound
8821 to a list of string/output-path pairs made from @var{inputs}.
8822 Optionally, @var{env-vars} is a list of string pairs specifying the name
8823 and value of environment variables visible to the builder. The builder
8824 terminates by passing the result of @var{exp} to @code{exit}; thus, when
8825 @var{exp} returns @code{#f}, the build is considered to have failed.
8827 @var{exp} is built using @var{guile-for-build} (a derivation). When
8828 @var{guile-for-build} is omitted or is @code{#f}, the value of the
8829 @code{%guile-for-build} fluid is used instead.
8831 See the @code{derivation} procedure for the meaning of
8832 @var{references-graphs}, @var{allowed-references},
8833 @var{disallowed-references}, @var{local-build?}, and
8834 @var{substitutable?}.
8838 Here's an example of a single-output derivation that creates a directory
8839 containing one file:
8842 (let ((builder '(let ((out (assoc-ref %outputs "out")))
8843 (mkdir out) ; create /gnu/store/@dots{}-goo
8844 (call-with-output-file (string-append out "/test")
8846 (display '(hello guix) p))))))
8847 (build-expression->derivation store "goo" builder))
8849 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
8853 @node The Store Monad
8854 @section The Store Monad
8858 The procedures that operate on the store described in the previous
8859 sections all take an open connection to the build daemon as their first
8860 argument. Although the underlying model is functional, they either have
8861 side effects or depend on the current state of the store.
8863 The former is inconvenient: the connection to the build daemon has to be
8864 carried around in all those functions, making it impossible to compose
8865 functions that do not take that parameter with functions that do. The
8866 latter can be problematic: since store operations have side effects
8867 and/or depend on external state, they have to be properly sequenced.
8869 @cindex monadic values
8870 @cindex monadic functions
8871 This is where the @code{(guix monads)} module comes in. This module
8872 provides a framework for working with @dfn{monads}, and a particularly
8873 useful monad for our uses, the @dfn{store monad}. Monads are a
8874 construct that allows two things: associating ``context'' with values
8875 (in our case, the context is the store), and building sequences of
8876 computations (here computations include accesses to the store). Values
8877 in a monad---values that carry this additional context---are called
8878 @dfn{monadic values}; procedures that return such values are called
8879 @dfn{monadic procedures}.
8881 Consider this ``normal'' procedure:
8884 (define (sh-symlink store)
8885 ;; Return a derivation that symlinks the 'bash' executable.
8886 (let* ((drv (package-derivation store bash))
8887 (out (derivation->output-path drv))
8888 (sh (string-append out "/bin/bash")))
8889 (build-expression->derivation store "sh"
8890 `(symlink ,sh %output))))
8893 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
8894 as a monadic function:
8897 (define (sh-symlink)
8898 ;; Same, but return a monadic value.
8899 (mlet %store-monad ((drv (package->derivation bash)))
8900 (gexp->derivation "sh"
8901 #~(symlink (string-append #$drv "/bin/bash")
8905 There are several things to note in the second version: the @code{store}
8906 parameter is now implicit and is ``threaded'' in the calls to the
8907 @code{package->derivation} and @code{gexp->derivation} monadic
8908 procedures, and the monadic value returned by @code{package->derivation}
8909 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
8911 As it turns out, the call to @code{package->derivation} can even be
8912 omitted since it will take place implicitly, as we will see later
8913 (@pxref{G-Expressions}):
8916 (define (sh-symlink)
8917 (gexp->derivation "sh"
8918 #~(symlink (string-append #$bash "/bin/bash")
8923 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
8924 @c for the funny quote.
8925 Calling the monadic @code{sh-symlink} has no effect. As someone once
8926 said, ``you exit a monad like you exit a building on fire: by running''.
8927 So, to exit the monad and get the desired effect, one must use
8928 @code{run-with-store}:
8931 (run-with-store (open-connection) (sh-symlink))
8932 @result{} /gnu/store/...-sh-symlink
8935 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
8936 new ``meta-commands'' to make it easier to deal with monadic procedures:
8937 @code{run-in-store}, and @code{enter-store-monad}. The former is used
8938 to ``run'' a single monadic value through the store:
8941 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
8942 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
8945 The latter enters a recursive REPL, where all the return values are
8946 automatically run through the store:
8949 scheme@@(guile-user)> ,enter-store-monad
8950 store-monad@@(guile-user) [1]> (package->derivation hello)
8951 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
8952 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
8953 $3 = "/gnu/store/@dots{}-foo"
8954 store-monad@@(guile-user) [1]> ,q
8955 scheme@@(guile-user)>
8959 Note that non-monadic values cannot be returned in the
8960 @code{store-monad} REPL.
8962 The main syntactic forms to deal with monads in general are provided by
8963 the @code{(guix monads)} module and are described below.
8965 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
8966 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
8970 @deffn {Scheme Syntax} return @var{val}
8971 Return a monadic value that encapsulates @var{val}.
8974 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
8975 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
8976 procedures @var{mproc}@dots{}@footnote{This operation is commonly
8977 referred to as ``bind'', but that name denotes an unrelated procedure in
8978 Guile. Thus we use this somewhat cryptic symbol inherited from the
8979 Haskell language.}. There can be one @var{mproc} or several of them, as
8984 (with-monad %state-monad
8986 (lambda (x) (return (+ 1 x)))
8987 (lambda (x) (return (* 2 x)))))
8991 @result{} some-state
8995 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
8997 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
8999 Bind the variables @var{var} to the monadic values @var{mval} in
9000 @var{body}, which is a sequence of expressions. As with the bind
9001 operator, this can be thought of as ``unpacking'' the raw, non-monadic
9002 value ``contained'' in @var{mval} and making @var{var} refer to that
9003 raw, non-monadic value within the scope of the @var{body}. The form
9004 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
9005 @var{val}, as per @code{let}. The binding operations occur in sequence
9006 from left to right. The last expression of @var{body} must be a monadic
9007 expression, and its result will become the result of the @code{mlet} or
9008 @code{mlet*} when run in the @var{monad}.
9010 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
9011 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
9014 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
9015 Bind @var{mexp} and the following monadic expressions in sequence,
9016 returning the result of the last expression. Every expression in the
9017 sequence must be a monadic expression.
9019 This is akin to @code{mlet}, except that the return values of the
9020 monadic expressions are ignored. In that sense, it is analogous to
9021 @code{begin}, but applied to monadic expressions.
9024 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
9025 When @var{condition} is true, evaluate the sequence of monadic
9026 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
9027 @var{condition} is false, return @code{*unspecified*} in the current
9028 monad. Every expression in the sequence must be a monadic expression.
9031 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
9032 When @var{condition} is false, evaluate the sequence of monadic
9033 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
9034 @var{condition} is true, return @code{*unspecified*} in the current
9035 monad. Every expression in the sequence must be a monadic expression.
9039 The @code{(guix monads)} module provides the @dfn{state monad}, which
9040 allows an additional value---the state---to be @emph{threaded} through
9041 monadic procedure calls.
9043 @defvr {Scheme Variable} %state-monad
9044 The state monad. Procedures in the state monad can access and change
9045 the state that is threaded.
9047 Consider the example below. The @code{square} procedure returns a value
9048 in the state monad. It returns the square of its argument, but also
9049 increments the current state value:
9053 (mlet %state-monad ((count (current-state)))
9054 (mbegin %state-monad
9055 (set-current-state (+ 1 count))
9058 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
9063 When ``run'' through @code{%state-monad}, we obtain that additional state
9064 value, which is the number of @code{square} calls.
9067 @deffn {Monadic Procedure} current-state
9068 Return the current state as a monadic value.
9071 @deffn {Monadic Procedure} set-current-state @var{value}
9072 Set the current state to @var{value} and return the previous state as a
9076 @deffn {Monadic Procedure} state-push @var{value}
9077 Push @var{value} to the current state, which is assumed to be a list,
9078 and return the previous state as a monadic value.
9081 @deffn {Monadic Procedure} state-pop
9082 Pop a value from the current state and return it as a monadic value.
9083 The state is assumed to be a list.
9086 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
9087 Run monadic value @var{mval} starting with @var{state} as the initial
9088 state. Return two values: the resulting value, and the resulting state.
9091 The main interface to the store monad, provided by the @code{(guix
9092 store)} module, is as follows.
9094 @defvr {Scheme Variable} %store-monad
9095 The store monad---an alias for @code{%state-monad}.
9097 Values in the store monad encapsulate accesses to the store. When its
9098 effect is needed, a value of the store monad must be ``evaluated'' by
9099 passing it to the @code{run-with-store} procedure (see below).
9102 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
9103 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
9104 open store connection.
9107 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
9108 Return as a monadic value the absolute file name in the store of the file
9109 containing @var{text}, a string. @var{references} is a list of store items that the
9110 resulting text file refers to; it defaults to the empty list.
9113 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
9114 Return as a monadic value the absolute file name in the store of the file
9115 containing @var{data}, a bytevector. @var{references} is a list of store
9116 items that the resulting binary file refers to; it defaults to the empty list.
9119 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
9120 [#:recursive? #t] [#:select? (const #t)]
9121 Return the name of @var{file} once interned in the store. Use
9122 @var{name} as its store name, or the basename of @var{file} if
9123 @var{name} is omitted.
9125 When @var{recursive?} is true, the contents of @var{file} are added
9126 recursively; if @var{file} designates a flat file and @var{recursive?}
9127 is true, its contents are added, and its permission bits are kept.
9129 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
9130 @var{stat})} for each directory entry, where @var{file} is the entry's
9131 absolute file name and @var{stat} is the result of @code{lstat}; exclude
9132 entries for which @var{select?} does not return true.
9134 The example below adds a file to the store, under two different names:
9137 (run-with-store (open-connection)
9138 (mlet %store-monad ((a (interned-file "README"))
9139 (b (interned-file "README" "LEGU-MIN")))
9140 (return (list a b))))
9142 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
9147 The @code{(guix packages)} module exports the following package-related
9150 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
9151 [#:system (%current-system)] [#:target #f] @
9154 value in the absolute file name of @var{file} within the @var{output}
9155 directory of @var{package}. When @var{file} is omitted, return the name
9156 of the @var{output} directory of @var{package}. When @var{target} is
9157 true, use it as a cross-compilation target triplet.
9159 Note that this procedure does @emph{not} build @var{package}. Thus, the
9160 result might or might not designate an existing file. We recommend not
9161 using this procedure unless you know what you are doing.
9164 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
9165 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
9166 @var{target} [@var{system}]
9167 Monadic version of @code{package-derivation} and
9168 @code{package-cross-derivation} (@pxref{Defining Packages}).
9173 @section G-Expressions
9175 @cindex G-expression
9176 @cindex build code quoting
9177 So we have ``derivations'', which represent a sequence of build actions
9178 to be performed to produce an item in the store (@pxref{Derivations}).
9179 These build actions are performed when asking the daemon to actually
9180 build the derivations; they are run by the daemon in a container
9181 (@pxref{Invoking guix-daemon}).
9183 @cindex code staging
9184 @cindex staging, of code
9185 @cindex strata of code
9186 It should come as no surprise that we like to write these build actions
9187 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
9188 code@footnote{The term @dfn{stratum} in this context was coined by
9189 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
9190 Kiselyov, who has written insightful
9191 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
9192 on this topic}, refers to this kind of code generation as
9193 @dfn{staging}.}: the ``host code''---code that defines packages, talks
9194 to the daemon, etc.---and the ``build code''---code that actually
9195 performs build actions, such as making directories, invoking
9196 @command{make}, and so on (@pxref{Build Phases}).
9198 To describe a derivation and its build actions, one typically needs to
9199 embed build code inside host code. It boils down to manipulating build
9200 code as data, and the homoiconicity of Scheme---code has a direct
9201 representation as data---comes in handy for that. But we need more than
9202 the normal @code{quasiquote} mechanism in Scheme to construct build
9205 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
9206 S-expressions adapted to build expressions. G-expressions, or
9207 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
9208 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
9209 @code{#$}, and @code{#$@@}), which are comparable to
9210 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
9211 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
9212 GNU Guile Reference Manual}). However, there are major differences:
9216 Gexps are meant to be written to a file and run or manipulated by other
9220 When a high-level object such as a package or derivation is unquoted
9221 inside a gexp, the result is as if its output file name had been
9225 Gexps carry information about the packages or derivations they refer to,
9226 and these dependencies are automatically added as inputs to the build
9227 processes that use them.
9230 @cindex lowering, of high-level objects in gexps
9231 This mechanism is not limited to package and derivation
9232 objects: @dfn{compilers} able to ``lower'' other high-level objects to
9233 derivations or files in the store can be defined,
9234 such that these objects can also be inserted
9235 into gexps. For example, a useful type of high-level objects that can be
9236 inserted in a gexp is ``file-like objects'', which make it easy to
9237 add files to the store and to refer to them in
9238 derivations and such (see @code{local-file} and @code{plain-file}
9241 To illustrate the idea, here is an example of a gexp:
9248 (symlink (string-append #$coreutils "/bin/ls")
9252 This gexp can be passed to @code{gexp->derivation}; we obtain a
9253 derivation that builds a directory containing exactly one symlink to
9254 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
9257 (gexp->derivation "the-thing" build-exp)
9260 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
9261 substituted to the reference to the @var{coreutils} package in the
9262 actual build code, and @var{coreutils} is automatically made an input to
9263 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
9264 output)}) is replaced by a string containing the directory name of the
9265 output of the derivation.
9267 @cindex cross compilation
9268 In a cross-compilation context, it is useful to distinguish between
9269 references to the @emph{native} build of a package---that can run on the
9270 host---versus references to cross builds of a package. To that end, the
9271 @code{#+} plays the same role as @code{#$}, but is a reference to a
9272 native package build:
9275 (gexp->derivation "vi"
9278 (mkdir (string-append #$output "/bin"))
9279 (system* (string-append #+coreutils "/bin/ln")
9281 (string-append #$emacs "/bin/emacs")
9282 (string-append #$output "/bin/vi")))
9283 #:target "aarch64-linux-gnu")
9287 In the example above, the native build of @var{coreutils} is used, so
9288 that @command{ln} can actually run on the host; but then the
9289 cross-compiled build of @var{emacs} is referenced.
9291 @cindex imported modules, for gexps
9292 @findex with-imported-modules
9293 Another gexp feature is @dfn{imported modules}: sometimes you want to be
9294 able to use certain Guile modules from the ``host environment'' in the
9295 gexp, so those modules should be imported in the ``build environment''.
9296 The @code{with-imported-modules} form allows you to express that:
9299 (let ((build (with-imported-modules '((guix build utils))
9301 (use-modules (guix build utils))
9302 (mkdir-p (string-append #$output "/bin"))))))
9303 (gexp->derivation "empty-dir"
9306 (display "success!\n")
9311 In this example, the @code{(guix build utils)} module is automatically
9312 pulled into the isolated build environment of our gexp, such that
9313 @code{(use-modules (guix build utils))} works as expected.
9315 @cindex module closure
9316 @findex source-module-closure
9317 Usually you want the @emph{closure} of the module to be imported---i.e.,
9318 the module itself and all the modules it depends on---rather than just
9319 the module; failing to do that, attempts to use the module will fail
9320 because of missing dependent modules. The @code{source-module-closure}
9321 procedure computes the closure of a module by looking at its source file
9322 headers, which comes in handy in this case:
9325 (use-modules (guix modules)) ;for 'source-module-closure'
9327 (with-imported-modules (source-module-closure
9328 '((guix build utils)
9330 (gexp->derivation "something-with-vms"
9332 (use-modules (guix build utils)
9337 @cindex extensions, for gexps
9338 @findex with-extensions
9339 In the same vein, sometimes you want to import not just pure-Scheme
9340 modules, but also ``extensions'' such as Guile bindings to C libraries
9341 or other ``full-blown'' packages. Say you need the @code{guile-json}
9342 package available on the build side, here's how you would do it:
9345 (use-modules (gnu packages guile)) ;for 'guile-json'
9347 (with-extensions (list guile-json)
9348 (gexp->derivation "something-with-json"
9350 (use-modules (json))
9354 The syntactic form to construct gexps is summarized below.
9356 @deffn {Scheme Syntax} #~@var{exp}
9357 @deffnx {Scheme Syntax} (gexp @var{exp})
9358 Return a G-expression containing @var{exp}. @var{exp} may contain one
9359 or more of the following forms:
9363 @itemx (ungexp @var{obj})
9364 Introduce a reference to @var{obj}. @var{obj} may have one of the
9365 supported types, for example a package or a
9366 derivation, in which case the @code{ungexp} form is replaced by its
9367 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
9369 If @var{obj} is a list, it is traversed and references to supported
9370 objects are substituted similarly.
9372 If @var{obj} is another gexp, its contents are inserted and its
9373 dependencies are added to those of the containing gexp.
9375 If @var{obj} is another kind of object, it is inserted as is.
9377 @item #$@var{obj}:@var{output}
9378 @itemx (ungexp @var{obj} @var{output})
9379 This is like the form above, but referring explicitly to the
9380 @var{output} of @var{obj}---this is useful when @var{obj} produces
9381 multiple outputs (@pxref{Packages with Multiple Outputs}).
9384 @itemx #+@var{obj}:output
9385 @itemx (ungexp-native @var{obj})
9386 @itemx (ungexp-native @var{obj} @var{output})
9387 Same as @code{ungexp}, but produces a reference to the @emph{native}
9388 build of @var{obj} when used in a cross compilation context.
9390 @item #$output[:@var{output}]
9391 @itemx (ungexp output [@var{output}])
9392 Insert a reference to derivation output @var{output}, or to the main
9393 output when @var{output} is omitted.
9395 This only makes sense for gexps passed to @code{gexp->derivation}.
9398 @itemx (ungexp-splicing @var{lst})
9399 Like the above, but splices the contents of @var{lst} inside the
9403 @itemx (ungexp-native-splicing @var{lst})
9404 Like the above, but refers to native builds of the objects listed in
9409 G-expressions created by @code{gexp} or @code{#~} are run-time objects
9410 of the @code{gexp?} type (see below).
9413 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
9414 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
9415 in their execution environment.
9417 Each item in @var{modules} can be the name of a module, such as
9418 @code{(guix build utils)}, or it can be a module name, followed by an
9419 arrow, followed by a file-like object:
9422 `((guix build utils)
9424 ((guix config) => ,(scheme-file "config.scm"
9425 #~(define-module @dots{}))))
9429 In the example above, the first two modules are taken from the search
9430 path, and the last one is created from the given file-like object.
9432 This form has @emph{lexical} scope: it has an effect on the gexps
9433 directly defined in @var{body}@dots{}, but not on those defined, say, in
9434 procedures called from @var{body}@dots{}.
9437 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
9438 Mark the gexps defined in @var{body}@dots{} as requiring
9439 @var{extensions} in their build and execution environment.
9440 @var{extensions} is typically a list of package objects such as those
9441 defined in the @code{(gnu packages guile)} module.
9443 Concretely, the packages listed in @var{extensions} are added to the
9444 load path while compiling imported modules in @var{body}@dots{}; they
9445 are also added to the load path of the gexp returned by
9449 @deffn {Scheme Procedure} gexp? @var{obj}
9450 Return @code{#t} if @var{obj} is a G-expression.
9453 G-expressions are meant to be written to disk, either as code building
9454 some derivation, or as plain files in the store. The monadic procedures
9455 below allow you to do that (@pxref{The Store Monad}, for more
9456 information about monads).
9458 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
9459 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
9460 [#:hash #f] [#:hash-algo #f] @
9461 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
9462 [#:module-path @code{%load-path}] @
9463 [#:effective-version "2.2"] @
9464 [#:references-graphs #f] [#:allowed-references #f] @
9465 [#:disallowed-references #f] @
9466 [#:leaked-env-vars #f] @
9467 [#:script-name (string-append @var{name} "-builder")] @
9468 [#:deprecation-warnings #f] @
9469 [#:local-build? #f] [#:substitutable? #t] @
9470 [#:properties '()] [#:guile-for-build #f]
9471 Return a derivation @var{name} that runs @var{exp} (a gexp) with
9472 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
9473 stored in a file called @var{script-name}. When @var{target} is true,
9474 it is used as the cross-compilation target triplet for packages referred
9477 @var{modules} is deprecated in favor of @code{with-imported-modules}.
9479 make @var{modules} available in the evaluation context of @var{exp};
9480 @var{modules} is a list of names of Guile modules searched in
9481 @var{module-path} to be copied in the store, compiled, and made available in
9482 the load path during the execution of @var{exp}---e.g., @code{((guix
9483 build utils) (guix build gnu-build-system))}.
9485 @var{effective-version} determines the string to use when adding extensions of
9486 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
9488 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
9491 When @var{references-graphs} is true, it must be a list of tuples of one of the
9495 (@var{file-name} @var{package})
9496 (@var{file-name} @var{package} @var{output})
9497 (@var{file-name} @var{derivation})
9498 (@var{file-name} @var{derivation} @var{output})
9499 (@var{file-name} @var{store-item})
9502 The right-hand-side of each element of @var{references-graphs} is automatically made
9503 an input of the build process of @var{exp}. In the build environment, each
9504 @var{file-name} contains the reference graph of the corresponding item, in a simple
9507 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
9508 In the latter case, the list denotes store items that the result is allowed to
9509 refer to. Any reference to another store item will lead to a build error.
9510 Similarly for @var{disallowed-references}, which can list items that must not be
9511 referenced by the outputs.
9513 @var{deprecation-warnings} determines whether to show deprecation warnings while
9514 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
9516 The other arguments are as for @code{derivation} (@pxref{Derivations}).
9519 @cindex file-like objects
9520 The @code{local-file}, @code{plain-file}, @code{computed-file},
9521 @code{program-file}, and @code{scheme-file} procedures below return
9522 @dfn{file-like objects}. That is, when unquoted in a G-expression,
9523 these objects lead to a file in the store. Consider this G-expression:
9526 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
9527 #$(local-file "/tmp/my-nscd.conf"))
9530 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
9531 to the store. Once expanded, for instance @i{via}
9532 @code{gexp->derivation}, the G-expression refers to that copy under
9533 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
9534 does not have any effect on what the G-expression does.
9535 @code{plain-file} can be used similarly; it differs in that the file
9536 content is directly passed as a string.
9538 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
9539 [#:recursive? #f] [#:select? (const #t)]
9540 Return an object representing local file @var{file} to add to the store;
9541 this object can be used in a gexp. If @var{file} is a literal string
9542 denoting a relative file name, it is looked up relative to the source
9543 file where it appears; if @var{file} is not a literal string, it is
9544 looked up relative to the current working directory at run time.
9545 @var{file} will be added to the store under @var{name}--by default the
9546 base name of @var{file}.
9548 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
9549 designates a flat file and @var{recursive?} is true, its contents are added, and its
9550 permission bits are kept.
9552 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
9553 @var{stat})} for each directory entry, where @var{file} is the entry's
9554 absolute file name and @var{stat} is the result of @code{lstat}; exclude
9555 entries for which @var{select?} does not return true.
9557 This is the declarative counterpart of the @code{interned-file} monadic
9558 procedure (@pxref{The Store Monad, @code{interned-file}}).
9561 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
9562 Return an object representing a text file called @var{name} with the given
9563 @var{content} (a string or a bytevector) to be added to the store.
9565 This is the declarative counterpart of @code{text-file}.
9568 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
9571 Return an object representing the store item @var{name}, a file or
9572 directory computed by @var{gexp}. When @var{local-build?} is true (the
9573 default), the derivation is built locally. @var{options} is a list of
9574 additional arguments to pass to @code{gexp->derivation}.
9576 This is the declarative counterpart of @code{gexp->derivation}.
9579 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
9580 [#:guile (default-guile)] [#:module-path %load-path] @
9581 [#:system (%current-system)] [#:target #f]
9582 Return an executable script @var{name} that runs @var{exp} using
9583 @var{guile}, with @var{exp}'s imported modules in its search path.
9584 Look up @var{exp}'s modules in @var{module-path}.
9586 The example below builds a script that simply invokes the @command{ls}
9590 (use-modules (guix gexp) (gnu packages base))
9592 (gexp->script "list-files"
9593 #~(execl #$(file-append coreutils "/bin/ls")
9597 When ``running'' it through the store (@pxref{The Store Monad,
9598 @code{run-with-store}}), we obtain a derivation that produces an
9599 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
9602 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
9604 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
9608 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
9609 [#:guile #f] [#:module-path %load-path]
9610 Return an object representing the executable store item @var{name} that
9611 runs @var{gexp}. @var{guile} is the Guile package used to execute that
9612 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
9614 This is the declarative counterpart of @code{gexp->script}.
9617 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
9618 [#:set-load-path? #t] [#:module-path %load-path] @
9620 [#:guile (default-guile)]
9621 Return a derivation that builds a file @var{name} containing @var{exp}.
9622 When @var{splice?} is true, @var{exp} is considered to be a list of
9623 expressions that will be spliced in the resulting file.
9625 When @var{set-load-path?} is true, emit code in the resulting file to
9626 set @code{%load-path} and @code{%load-compiled-path} to honor
9627 @var{exp}'s imported modules. Look up @var{exp}'s modules in
9630 The resulting file holds references to all the dependencies of @var{exp}
9631 or a subset thereof.
9634 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
9635 [#:splice? #f] [#:set-load-path? #t]
9636 Return an object representing the Scheme file @var{name} that contains
9639 This is the declarative counterpart of @code{gexp->file}.
9642 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
9643 Return as a monadic value a derivation that builds a text file
9644 containing all of @var{text}. @var{text} may list, in addition to
9645 strings, objects of any type that can be used in a gexp: packages,
9646 derivations, local file objects, etc. The resulting store file holds
9647 references to all these.
9649 This variant should be preferred over @code{text-file} anytime the file
9650 to create will reference items from the store. This is typically the
9651 case when building a configuration file that embeds store file names,
9655 (define (profile.sh)
9656 ;; Return the name of a shell script in the store that
9657 ;; initializes the 'PATH' environment variable.
9658 (text-file* "profile.sh"
9659 "export PATH=" coreutils "/bin:"
9660 grep "/bin:" sed "/bin\n"))
9663 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
9664 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
9665 preventing them from being garbage-collected during its lifetime.
9668 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
9669 Return an object representing store file @var{name} containing
9670 @var{text}. @var{text} is a sequence of strings and file-like objects,
9674 (mixed-text-file "profile"
9675 "export PATH=" coreutils "/bin:" grep "/bin")
9678 This is the declarative counterpart of @code{text-file*}.
9681 @deffn {Scheme Procedure} file-union @var{name} @var{files}
9682 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
9683 Each item in @var{files} must be a two-element list where the first element is the
9684 file name to use in the new directory, and the second element is a gexp
9685 denoting the target file. Here's an example:
9689 `(("hosts" ,(plain-file "hosts"
9690 "127.0.0.1 localhost"))
9691 ("bashrc" ,(plain-file "bashrc"
9692 "alias ls='ls --color=auto'"))))
9695 This yields an @code{etc} directory containing these two files.
9698 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
9699 Return a directory that is the union of @var{things}, where @var{things} is a list of
9700 file-like objects denoting directories. For example:
9703 (directory-union "guile+emacs" (list guile emacs))
9706 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
9709 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
9710 Return a file-like object that expands to the concatenation of @var{obj}
9711 and @var{suffix}, where @var{obj} is a lowerable object and each
9712 @var{suffix} is a string.
9714 As an example, consider this gexp:
9717 (gexp->script "run-uname"
9718 #~(system* #$(file-append coreutils
9722 The same effect could be achieved with:
9725 (gexp->script "run-uname"
9726 #~(system* (string-append #$coreutils
9730 There is one difference though: in the @code{file-append} case, the
9731 resulting script contains the absolute file name as a string, whereas in
9732 the second case, the resulting script contains a @code{(string-append
9733 @dots{})} expression to construct the file name @emph{at run time}.
9736 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
9737 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
9738 Bind @var{system} to the currently targeted system---e.g.,
9739 @code{"x86_64-linux"}---within @var{body}.
9741 In the second case, additionally bind @var{target} to the current
9742 cross-compilation target---a GNU triplet such as
9743 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
9746 @code{let-system} is useful in the occasional case where the object
9747 spliced into the gexp depends on the target system, as in this example:
9751 #+(let-system system
9752 (cond ((string-prefix? "armhf-" system)
9753 (file-append qemu "/bin/qemu-system-arm"))
9754 ((string-prefix? "x86_64-" system)
9755 (file-append qemu "/bin/qemu-system-x86_64"))
9758 "-net" "user" #$image)
9762 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
9763 This macro is similar to the @code{parameterize} form for
9764 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
9765 Guile Reference Manual}). The key difference is that it takes effect
9766 when the file-like object returned by @var{exp} is lowered to a
9767 derivation or store item.
9769 A typical use of @code{with-parameters} is to force the system in effect
9773 (with-parameters ((%current-system "i686-linux"))
9777 The example above returns an object that corresponds to the i686 build
9778 of Coreutils, regardless of the current value of @code{%current-system}.
9782 Of course, in addition to gexps embedded in ``host'' code, there are
9783 also modules containing build tools. To make it clear that they are
9784 meant to be used in the build stratum, these modules are kept in the
9785 @code{(guix build @dots{})} name space.
9787 @cindex lowering, of high-level objects in gexps
9788 Internally, high-level objects are @dfn{lowered}, using their compiler,
9789 to either derivations or store items. For instance, lowering a package
9790 yields a derivation, and lowering a @code{plain-file} yields a store
9791 item. This is achieved using the @code{lower-object} monadic procedure.
9793 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
9795 Return as a value in @code{%store-monad} the derivation or store item
9796 corresponding to @var{obj} for @var{system}, cross-compiling for
9797 @var{target} if @var{target} is true. @var{obj} must be an object that
9798 has an associated gexp compiler, such as a @code{<package>}.
9801 @node Invoking guix repl
9802 @section Invoking @command{guix repl}
9804 @cindex REPL, read-eval-print loop, script
9805 The @command{guix repl} command makes it easier to program Guix in Guile
9806 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
9807 programming (@pxref{Using Guile Interactively,,, guile,
9808 GNU Guile Reference Manual}), or by running Guile scripts
9809 (@pxref{Running Guile Scripts,,, guile,
9810 GNU Guile Reference Manual}).
9811 Compared to just launching the @command{guile}
9812 command, @command{guix repl} guarantees that all the Guix modules and all its
9813 dependencies are available in the search path.
9815 The general syntax is:
9818 guix repl @var{options} [@var{file} @var{args}]
9821 When a @var{file} argument is provided, @var{file} is
9822 executed as a Guile scripts:
9825 guix repl my-script.scm
9828 To pass arguments to the script, use @code{--} to prevent them from
9829 being interpreted as arguments to @command{guix repl} itself:
9832 guix repl -- my-script.scm --input=foo.txt
9835 To make a script executable directly from the shell, using the guix
9836 executable that is on the user's search path, add the following two
9837 lines at the top of the script:
9840 @code{#!/usr/bin/env -S guix repl --}
9844 Without a file name argument, a Guile REPL is started:
9848 scheme@@(guile-user)> ,use (gnu packages base)
9849 scheme@@(guile-user)> coreutils
9850 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
9854 In addition, @command{guix repl} implements a simple machine-readable REPL
9855 protocol for use by @code{(guix inferior)}, a facility to interact with
9856 @dfn{inferiors}, separate processes running a potentially different revision
9859 The available options are as follows:
9862 @item --type=@var{type}
9863 @itemx -t @var{type}
9864 Start a REPL of the given @var{TYPE}, which can be one of the following:
9868 This is default, and it spawns a standard full-featured Guile REPL.
9870 Spawn a REPL that uses the machine-readable protocol. This is the protocol
9871 that the @code{(guix inferior)} module speaks.
9874 @item --listen=@var{endpoint}
9875 By default, @command{guix repl} reads from standard input and writes to
9876 standard output. When this option is passed, it will instead listen for
9877 connections on @var{endpoint}. Here are examples of valid options:
9880 @item --listen=tcp:37146
9881 Accept connections on localhost on port 37146.
9883 @item --listen=unix:/tmp/socket
9884 Accept connections on the Unix-domain socket @file{/tmp/socket}.
9887 @item --load-path=@var{directory}
9888 @itemx -L @var{directory}
9889 Add @var{directory} to the front of the package module search path
9890 (@pxref{Package Modules}).
9892 This allows users to define their own packages and make them visible to
9896 Inhibit loading of the @file{~/.guile} file. By default, that
9897 configuration file is loaded when spawning a @code{guile} REPL.
9900 @c *********************************************************************
9904 This section describes Guix command-line utilities. Some of them are
9905 primarily targeted at developers and users who write new package
9906 definitions, while others are more generally useful. They complement
9907 the Scheme programming interface of Guix in a convenient way.
9910 * Invoking guix build:: Building packages from the command line.
9911 * Invoking guix edit:: Editing package definitions.
9912 * Invoking guix download:: Downloading a file and printing its hash.
9913 * Invoking guix hash:: Computing the cryptographic hash of a file.
9914 * Invoking guix import:: Importing package definitions.
9915 * Invoking guix refresh:: Updating package definitions.
9916 * Invoking guix lint:: Finding errors in package definitions.
9917 * Invoking guix size:: Profiling disk usage.
9918 * Invoking guix graph:: Visualizing the graph of packages.
9919 * Invoking guix publish:: Sharing substitutes.
9920 * Invoking guix challenge:: Challenging substitute servers.
9921 * Invoking guix copy:: Copying to and from a remote store.
9922 * Invoking guix container:: Process isolation.
9923 * Invoking guix weather:: Assessing substitute availability.
9924 * Invoking guix processes:: Listing client processes.
9927 @node Invoking guix build
9928 @section Invoking @command{guix build}
9930 @cindex package building
9931 @cindex @command{guix build}
9932 The @command{guix build} command builds packages or derivations and
9933 their dependencies, and prints the resulting store paths. Note that it
9934 does not modify the user's profile---this is the job of the
9935 @command{guix package} command (@pxref{Invoking guix package}). Thus,
9936 it is mainly useful for distribution developers.
9938 The general syntax is:
9941 guix build @var{options} @var{package-or-derivation}@dots{}
9944 As an example, the following command builds the latest versions of Emacs
9945 and of Guile, displays their build logs, and finally displays the
9946 resulting directories:
9949 guix build emacs guile
9952 Similarly, the following command builds all the available packages:
9955 guix build --quiet --keep-going \
9956 `guix package -A | cut -f1,2 --output-delimiter=@@`
9959 @var{package-or-derivation} may be either the name of a package found in
9960 the software distribution such as @code{coreutils} or
9961 @code{coreutils@@8.20}, or a derivation such as
9962 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
9963 package with the corresponding name (and optionally version) is searched
9964 for among the GNU distribution modules (@pxref{Package Modules}).
9966 Alternatively, the @option{--expression} option may be used to specify a
9967 Scheme expression that evaluates to a package; this is useful when
9968 disambiguating among several same-named packages or package variants is
9971 There may be zero or more @var{options}. The available options are
9972 described in the subsections below.
9975 * Common Build Options:: Build options for most commands.
9976 * Package Transformation Options:: Creating variants of packages.
9977 * Additional Build Options:: Options specific to 'guix build'.
9978 * Debugging Build Failures:: Real life packaging experience.
9981 @node Common Build Options
9982 @subsection Common Build Options
9984 A number of options that control the build process are common to
9985 @command{guix build} and other commands that can spawn builds, such as
9986 @command{guix package} or @command{guix archive}. These are the
9991 @item --load-path=@var{directory}
9992 @itemx -L @var{directory}
9993 Add @var{directory} to the front of the package module search path
9994 (@pxref{Package Modules}).
9996 This allows users to define their own packages and make them visible to
9997 the command-line tools.
10001 Keep the build tree of failed builds. Thus, if a build fails, its build
10002 tree is kept under @file{/tmp}, in a directory whose name is shown at
10003 the end of the build log. This is useful when debugging build issues.
10004 @xref{Debugging Build Failures}, for tips and tricks on how to debug
10007 This option implies @option{--no-offload}, and it has no effect when
10008 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
10009 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
10013 Keep going when some of the derivations fail to build; return only once
10014 all the builds have either completed or failed.
10016 The default behavior is to stop as soon as one of the specified
10017 derivations has failed.
10021 Do not build the derivations.
10023 @anchor{fallback-option}
10025 When substituting a pre-built binary fails, fall back to building
10026 packages locally (@pxref{Substitution Failure}).
10028 @item --substitute-urls=@var{urls}
10029 @anchor{client-substitute-urls}
10030 Consider @var{urls} the whitespace-separated list of substitute source
10031 URLs, overriding the default list of URLs of @command{guix-daemon}
10032 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
10034 This means that substitutes may be downloaded from @var{urls}, provided
10035 they are signed by a key authorized by the system administrator
10036 (@pxref{Substitutes}).
10038 When @var{urls} is the empty string, substitutes are effectively
10041 @item --no-substitutes
10042 Do not use substitutes for build products. That is, always build things
10043 locally instead of allowing downloads of pre-built binaries
10044 (@pxref{Substitutes}).
10047 Do not ``graft'' packages. In practice, this means that package updates
10048 available as grafts are not applied. @xref{Security Updates}, for more
10049 information on grafts.
10051 @item --rounds=@var{n}
10052 Build each derivation @var{n} times in a row, and raise an error if
10053 consecutive build results are not bit-for-bit identical.
10055 This is a useful way to detect non-deterministic builds processes.
10056 Non-deterministic build processes are a problem because they make it
10057 practically impossible for users to @emph{verify} whether third-party
10058 binaries are genuine. @xref{Invoking guix challenge}, for more.
10060 When used in conjunction with @option{--keep-failed}, the differing
10061 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
10062 This makes it easy to look for differences between the two results.
10065 Do not use offload builds to other machines (@pxref{Daemon Offload
10066 Setup}). That is, always build things locally instead of offloading
10067 builds to remote machines.
10069 @item --max-silent-time=@var{seconds}
10070 When the build or substitution process remains silent for more than
10071 @var{seconds}, terminate it and report a build failure.
10073 By default, the daemon's setting is honored (@pxref{Invoking
10074 guix-daemon, @option{--max-silent-time}}).
10076 @item --timeout=@var{seconds}
10077 Likewise, when the build or substitution process lasts for more than
10078 @var{seconds}, terminate it and report a build failure.
10080 By default, the daemon's setting is honored (@pxref{Invoking
10081 guix-daemon, @option{--timeout}}).
10083 @c Note: This option is actually not part of %standard-build-options but
10084 @c most programs honor it.
10085 @cindex verbosity, of the command-line tools
10086 @cindex build logs, verbosity
10087 @item -v @var{level}
10088 @itemx --verbosity=@var{level}
10089 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
10090 output is produced, 1 is for quiet output, and 2 shows all the build log
10091 output on standard error.
10093 @item --cores=@var{n}
10095 Allow the use of up to @var{n} CPU cores for the build. The special
10096 value @code{0} means to use as many CPU cores as available.
10098 @item --max-jobs=@var{n}
10100 Allow at most @var{n} build jobs in parallel. @xref{Invoking
10101 guix-daemon, @option{--max-jobs}}, for details about this option and the
10102 equivalent @command{guix-daemon} option.
10104 @item --debug=@var{level}
10105 Produce debugging output coming from the build daemon. @var{level} must be an
10106 integer between 0 and 5; higher means more verbose output. Setting a level of
10107 4 or more may be helpful when debugging setup issues with the build daemon.
10111 Behind the scenes, @command{guix build} is essentially an interface to
10112 the @code{package-derivation} procedure of the @code{(guix packages)}
10113 module, and to the @code{build-derivations} procedure of the @code{(guix
10114 derivations)} module.
10116 In addition to options explicitly passed on the command line,
10117 @command{guix build} and other @command{guix} commands that support
10118 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
10120 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
10121 Users can define this variable to a list of command line options that
10122 will automatically be used by @command{guix build} and other
10123 @command{guix} commands that can perform builds, as in the example
10127 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
10130 These options are parsed independently, and the result is appended to
10131 the parsed command-line options.
10135 @node Package Transformation Options
10136 @subsection Package Transformation Options
10138 @cindex package variants
10139 Another set of command-line options supported by @command{guix build}
10140 and also @command{guix package} are @dfn{package transformation
10141 options}. These are options that make it possible to define @dfn{package
10142 variants}---for instance, packages built from different source code.
10143 This is a convenient way to create customized packages on the fly
10144 without having to type in the definitions of package variants
10145 (@pxref{Defining Packages}).
10147 Package transformation options are preserved across upgrades:
10148 @command{guix upgrade} attempts to apply transformation options
10149 initially used when creating the profile to the upgraded packages.
10151 The available options are listed below. Most commands support them and
10152 also support a @option{--help-transform} option that lists all the
10153 available options and a synopsis (these options are not shown in the
10154 @option{--help} output for brevity).
10158 @item --with-source=@var{source}
10159 @itemx --with-source=@var{package}=@var{source}
10160 @itemx --with-source=@var{package}@@@var{version}=@var{source}
10161 Use @var{source} as the source of @var{package}, and @var{version} as
10162 its version number.
10163 @var{source} must be a file name or a URL, as for @command{guix
10164 download} (@pxref{Invoking guix download}).
10166 When @var{package} is omitted,
10167 it is taken to be the package name specified on the
10168 command line that matches the base of @var{source}---e.g.,
10169 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
10170 package is @code{guile}.
10172 Likewise, when @var{version} is omitted, the version string is inferred from
10173 @var{source}; in the previous example, it is @code{2.0.10}.
10175 This option allows users to try out versions of packages other than the
10176 one provided by the distribution. The example below downloads
10177 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
10178 the @code{ed} package:
10181 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
10184 As a developer, @option{--with-source} makes it easy to test release
10188 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
10191 @dots{} or to build from a checkout in a pristine environment:
10194 $ git clone git://git.sv.gnu.org/guix.git
10195 $ guix build guix --with-source=guix@@1.0=./guix
10198 @item --with-input=@var{package}=@var{replacement}
10199 Replace dependency on @var{package} by a dependency on
10200 @var{replacement}. @var{package} must be a package name, and
10201 @var{replacement} must be a package specification such as @code{guile}
10202 or @code{guile@@1.8}.
10204 For instance, the following command builds Guix, but replaces its
10205 dependency on the current stable version of Guile with a dependency on
10206 the legacy version of Guile, @code{guile@@2.0}:
10209 guix build --with-input=guile=guile@@2.0 guix
10212 This is a recursive, deep replacement. So in this example, both
10213 @code{guix} and its dependency @code{guile-json} (which also depends on
10214 @code{guile}) get rebuilt against @code{guile@@2.0}.
10216 This is implemented using the @code{package-input-rewriting} Scheme
10217 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
10219 @item --with-graft=@var{package}=@var{replacement}
10220 This is similar to @option{--with-input} but with an important difference:
10221 instead of rebuilding the whole dependency chain, @var{replacement} is
10222 built and then @dfn{grafted} onto the binaries that were initially
10223 referring to @var{package}. @xref{Security Updates}, for more
10224 information on grafts.
10226 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
10227 and all its dependencies, replacing references to the version of GnuTLS
10228 they currently refer to:
10231 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
10234 This has the advantage of being much faster than rebuilding everything.
10235 But there is a caveat: it works if and only if @var{package} and
10236 @var{replacement} are strictly compatible---for example, if they provide
10237 a library, the application binary interface (ABI) of those libraries
10238 must be compatible. If @var{replacement} is somehow incompatible with
10239 @var{package}, then the resulting package may be unusable. Use with
10242 @cindex debugging info, rebuilding
10243 @item --with-debug-info=@var{package}
10244 Build @var{package} in a way that preserves its debugging info and graft
10245 it onto packages that depend on it. This is useful if @var{package}
10246 does not already provide debugging info as a @code{debug} output
10247 (@pxref{Installing Debugging Files}).
10249 For example, suppose you're experiencing a crash in Inkscape and would
10250 like to see what's up in GLib, a library deep down in Inkscape's
10251 dependency graph. GLib lacks a @code{debug} output, so debugging is
10252 tough. Fortunately, you rebuild GLib with debugging info and tack it on
10256 guix install inkscape --with-debug-info=glib
10259 Only GLib needs to be recompiled so this takes a reasonable amount of
10260 time. @xref{Installing Debugging Files}, for more info.
10263 Under the hood, this option works by passing the @samp{#:strip-binaries?
10264 #f} to the build system of the package of interest (@pxref{Build
10265 Systems}). Most build systems support that option but some do not. In
10266 that case, an error is raised.
10268 Likewise, if a C/C++ package is built without @code{-g} (which is rarely
10269 the case), debugging info will remain unavailable even when
10270 @code{#:strip-binaries?} is false.
10273 @cindex tool chain, changing the build tool chain of a package
10274 @item --with-c-toolchain=@var{package}=@var{toolchain}
10275 This option changes the compilation of @var{package} and everything that
10276 depends on it so that they get built with @var{toolchain} instead of the
10277 default GNU tool chain for C/C++.
10279 Consider this example:
10282 guix build octave-cli \
10283 --with-c-toolchain=fftw=gcc-toolchain@@10 \
10284 --with-c-toolchain=fftwf=gcc-toolchain@@10
10287 The command above builds a variant of the @code{fftw} and @code{fftwf}
10288 packages using version 10 of @code{gcc-toolchain} instead of the default
10289 tool chain, and then builds a variant of the GNU@tie{}Octave
10290 command-line interface using them. GNU@tie{}Octave itself is also built
10291 with @code{gcc-toolchain@@10}.
10293 This other example builds the Hardware Locality (@code{hwloc}) library
10294 and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
10298 guix build --with-c-toolchain=hwloc=clang-toolchain \
10299 intel-mpi-benchmarks
10303 There can be application binary interface (ABI) incompatibilities among
10304 tool chains. This is particularly true of the C++ standard library and
10305 run-time support libraries such as that of OpenMP. By rebuilding all
10306 dependents with the same tool chain, @option{--with-c-toolchain} minimizes
10307 the risks of incompatibility but cannot entirely eliminate them. Choose
10308 @var{package} wisely.
10311 @item --with-git-url=@var{package}=@var{url}
10312 @cindex Git, using the latest commit
10313 @cindex latest commit, building
10314 Build @var{package} from the latest commit of the @code{master} branch of the
10315 Git repository at @var{url}. Git sub-modules of the repository are fetched,
10318 For example, the following command builds the NumPy Python library against the
10319 latest commit of the master branch of Python itself:
10322 guix build python-numpy \
10323 --with-git-url=python=https://github.com/python/cpython
10326 This option can also be combined with @option{--with-branch} or
10327 @option{--with-commit} (see below).
10329 @cindex continuous integration
10330 Obviously, since it uses the latest commit of the given branch, the result of
10331 such a command varies over time. Nevertheless it is a convenient way to
10332 rebuild entire software stacks against the latest commit of one or more
10333 packages. This is particularly useful in the context of continuous
10336 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
10337 consecutive accesses to the same repository. You may want to clean it up once
10338 in a while to save disk space.
10340 @item --with-branch=@var{package}=@var{branch}
10341 Build @var{package} from the latest commit of @var{branch}. If the
10342 @code{source} field of @var{package} is an origin with the @code{git-fetch}
10343 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
10344 repository URL is taken from that @code{source}. Otherwise you have to use
10345 @option{--with-git-url} to specify the URL of the Git repository.
10347 For instance, the following command builds @code{guile-sqlite3} from the
10348 latest commit of its @code{master} branch, and then builds @code{guix} (which
10349 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
10350 specific @code{guile-sqlite3} build:
10353 guix build --with-branch=guile-sqlite3=master cuirass
10356 @item --with-commit=@var{package}=@var{commit}
10357 This is similar to @option{--with-branch}, except that it builds from
10358 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
10359 Git commit SHA1 identifier or a tag.
10361 @item --with-patch=@var{package}=@var{file}
10362 Add @var{file} to the list of patches applied to @var{package}, where
10363 @var{package} is a spec such as @code{python@@3.8} or @code{glibc}.
10364 @var{file} must contain a patch; it is applied with the flags specified
10365 in the @code{origin} of @var{package} (@pxref{origin Reference}), which
10366 by default includes @code{-p1} (@pxref{patch Directories,,, diffutils,
10367 Comparing and Merging Files}).
10369 As an example, the command below rebuilds Coreutils with the GNU C
10370 Library (glibc) patched with the given patch:
10373 guix build coreutils --with-patch=glibc=./glibc-frob.patch
10376 In this example, glibc itself as well as everything that leads to
10377 Coreutils in the dependency graph is rebuilt.
10379 @cindex test suite, skipping
10380 @item --without-tests=@var{package}
10381 Build @var{package} without running its tests. This can be useful in
10382 situations where you want to skip the lengthy test suite of a
10383 intermediate package, or if a package's test suite fails in a
10384 non-deterministic fashion. It should be used with care because running
10385 the test suite is a good way to ensure a package is working as intended.
10387 Turning off tests leads to a different store item. Consequently, when
10388 using this option, anything that depends on @var{package} must be
10389 rebuilt, as in this example:
10392 guix install --without-tests=python python-notebook
10395 The command above installs @code{python-notebook} on top of
10396 @code{python} built without running its test suite. To do so, it also
10397 rebuilds everything that depends on @code{python}, including
10398 @code{python-notebook} itself.
10400 Internally, @option{--without-tests} relies on changing the
10401 @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
10402 Systems}). Note that some packages use a customized @code{check} phase
10403 that does not respect a @code{#:tests? #f} setting. Therefore,
10404 @option{--without-tests} has no effect on these packages.
10408 Wondering how to achieve the same effect using Scheme code, for example
10409 in your manifest, or how to write your own package transformation?
10410 @xref{Defining Package Variants}, for an overview of the programming
10411 interfaces available.
10413 @node Additional Build Options
10414 @subsection Additional Build Options
10416 The command-line options presented below are specific to @command{guix
10423 Build quietly, without displaying the build log; this is equivalent to
10424 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
10425 (or similar) and can always be retrieved using the @option{--log-file} option.
10427 @item --file=@var{file}
10428 @itemx -f @var{file}
10429 Build the package, derivation, or other file-like object that the code within
10430 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
10432 As an example, @var{file} might contain a package definition like this
10433 (@pxref{Defining Packages}):
10436 @include package-hello.scm
10439 The @var{file} may also contain a JSON representation of one or more
10440 package definitions. Running @code{guix build -f} on @file{hello.json}
10441 with the following contents would result in building the packages
10442 @code{myhello} and @code{greeter}:
10445 @verbatiminclude package-hello.json
10448 @item --manifest=@var{manifest}
10449 @itemx -m @var{manifest}
10450 Build all packages listed in the given @var{manifest}
10451 (@pxref{profile-manifest, @option{--manifest}}).
10453 @item --expression=@var{expr}
10454 @itemx -e @var{expr}
10455 Build the package or derivation @var{expr} evaluates to.
10457 For example, @var{expr} may be @code{(@@ (gnu packages guile)
10458 guile-1.8)}, which unambiguously designates this specific variant of
10459 version 1.8 of Guile.
10461 Alternatively, @var{expr} may be a G-expression, in which case it is used
10462 as a build program passed to @code{gexp->derivation}
10463 (@pxref{G-Expressions}).
10465 Lastly, @var{expr} may refer to a zero-argument monadic procedure
10466 (@pxref{The Store Monad}). The procedure must return a derivation as a
10467 monadic value, which is then passed through @code{run-with-store}.
10471 Build the source derivations of the packages, rather than the packages
10474 For instance, @code{guix build -S gcc} returns something like
10475 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
10478 The returned source tarball is the result of applying any patches and
10479 code snippets specified in the package @code{origin} (@pxref{Defining
10482 @cindex source, verification
10483 As with other derivations, the result of building a source derivation
10484 can be verified using the @option{--check} option (@pxref{build-check}).
10485 This is useful to validate that a (potentially already built or
10486 substituted, thus cached) package source matches against its declared
10489 Note that @command{guix build -S} compiles the sources only of the
10490 specified packages. They do not include the sources of statically
10491 linked dependencies and by themselves are insufficient for reproducing
10495 Fetch and return the source of @var{package-or-derivation} and all their
10496 dependencies, recursively. This is a handy way to obtain a local copy
10497 of all the source code needed to build @var{packages}, allowing you to
10498 eventually build them even without network access. It is an extension
10499 of the @option{--source} option and can accept one of the following
10500 optional argument values:
10504 This value causes the @option{--sources} option to behave in the same way
10505 as the @option{--source} option.
10508 Build the source derivations of all packages, including any source that
10509 might be listed as @code{inputs}. This is the default value.
10512 $ guix build --sources tzdata
10513 The following derivations will be built:
10514 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
10515 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
10519 Build the source derivations of all packages, as well of all transitive
10520 inputs to the packages. This can be used e.g.@: to
10521 prefetch package source for later offline building.
10524 $ guix build --sources=transitive tzdata
10525 The following derivations will be built:
10526 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
10527 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
10528 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
10529 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
10530 /gnu/store/@dots{}-make-4.1.tar.xz.drv
10531 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
10537 @item --system=@var{system}
10538 @itemx -s @var{system}
10539 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
10540 the system type of the build host. The @command{guix build} command allows
10541 you to repeat this option several times, in which case it builds for all the
10542 specified systems; other commands ignore extraneous @option{-s} options.
10545 The @option{--system} flag is for @emph{native} compilation and must not
10546 be confused with cross-compilation. See @option{--target} below for
10547 information on cross-compilation.
10550 An example use of this is on Linux-based systems, which can emulate
10551 different personalities. For instance, passing
10552 @option{--system=i686-linux} on an @code{x86_64-linux} system or
10553 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
10554 you to build packages in a complete 32-bit environment.
10557 Building for an @code{armhf-linux} system is unconditionally enabled on
10558 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
10559 allow for this functionality, notably the ThunderX.
10562 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
10563 is enabled (@pxref{Virtualization Services,
10564 @code{qemu-binfmt-service-type}}), you can build for any system for
10565 which a QEMU @code{binfmt_misc} handler is installed.
10567 Builds for a system other than that of the machine you are using can
10568 also be offloaded to a remote machine of the right architecture.
10569 @xref{Daemon Offload Setup}, for more information on offloading.
10571 @item --target=@var{triplet}
10572 @cindex cross-compilation
10573 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
10574 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
10575 configuration triplets,, autoconf, Autoconf}).
10577 @anchor{build-check}
10579 @cindex determinism, checking
10580 @cindex reproducibility, checking
10581 Rebuild @var{package-or-derivation}, which are already available in the
10582 store, and raise an error if the build results are not bit-for-bit
10585 This mechanism allows you to check whether previously installed
10586 substitutes are genuine (@pxref{Substitutes}), or whether the build result
10587 of a package is deterministic. @xref{Invoking guix challenge}, for more
10588 background information and tools.
10590 When used in conjunction with @option{--keep-failed}, the differing
10591 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
10592 This makes it easy to look for differences between the two results.
10595 @cindex repairing store items
10596 @cindex corruption, recovering from
10597 Attempt to repair the specified store items, if they are corrupt, by
10598 re-downloading or rebuilding them.
10600 This operation is not atomic and thus restricted to @code{root}.
10602 @item --derivations
10604 Return the derivation paths, not the output paths, of the given
10607 @item --root=@var{file}
10608 @itemx -r @var{file}
10609 @cindex GC roots, adding
10610 @cindex garbage collector roots, adding
10611 Make @var{file} a symlink to the result, and register it as a garbage
10614 Consequently, the results of this @command{guix build} invocation are
10615 protected from garbage collection until @var{file} is removed. When
10616 that option is omitted, build results are eligible for garbage
10617 collection as soon as the build completes. @xref{Invoking guix gc}, for
10621 @cindex build logs, access
10622 Return the build log file names or URLs for the given
10623 @var{package-or-derivation}, or raise an error if build logs are
10626 This works regardless of how packages or derivations are specified. For
10627 instance, the following invocations are equivalent:
10630 guix build --log-file `guix build -d guile`
10631 guix build --log-file `guix build guile`
10632 guix build --log-file guile
10633 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
10636 If a log is unavailable locally, and unless @option{--no-substitutes} is
10637 passed, the command looks for a corresponding log on one of the
10638 substitute servers (as specified with @option{--substitute-urls}).
10640 So for instance, imagine you want to see the build log of GDB on MIPS,
10641 but you are actually on an @code{x86_64} machine:
10644 $ guix build --log-file gdb -s aarch64-linux
10645 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
10648 You can freely access a huge library of build logs!
10651 @node Debugging Build Failures
10652 @subsection Debugging Build Failures
10654 @cindex build failures, debugging
10655 When defining a new package (@pxref{Defining Packages}), you will
10656 probably find yourself spending some time debugging and tweaking the
10657 build until it succeeds. To do that, you need to operate the build
10658 commands yourself in an environment as close as possible to the one the
10661 To that end, the first thing to do is to use the @option{--keep-failed}
10662 or @option{-K} option of @command{guix build}, which will keep the
10663 failed build tree in @file{/tmp} or whatever directory you specified as
10664 @env{TMPDIR} (@pxref{Invoking guix build, @option{--keep-failed}}).
10666 From there on, you can @command{cd} to the failed build tree and source
10667 the @file{environment-variables} file, which contains all the
10668 environment variable definitions that were in place when the build
10669 failed. So let's say you're debugging a build failure in package
10670 @code{foo}; a typical session would look like this:
10673 $ guix build foo -K
10674 @dots{} @i{build fails}
10675 $ cd /tmp/guix-build-foo.drv-0
10676 $ source ./environment-variables
10680 Now, you can invoke commands as if you were the daemon (almost) and
10681 troubleshoot your build process.
10683 Sometimes it happens that, for example, a package's tests pass when you
10684 run them manually but they fail when the daemon runs them. This can
10685 happen because the daemon runs builds in containers where, unlike in our
10686 environment above, network access is missing, @file{/bin/sh} does not
10687 exist, etc. (@pxref{Build Environment Setup}).
10689 In such cases, you may need to run inspect the build process from within
10690 a container similar to the one the build daemon creates:
10693 $ guix build -K foo
10695 $ cd /tmp/guix-build-foo.drv-0
10696 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
10697 [env]# source ./environment-variables
10701 Here, @command{guix environment -C} creates a container and spawns a new
10702 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
10703 strace gdb} part adds the @command{strace} and @command{gdb} commands to
10704 the container, which you may find handy while debugging. The
10705 @option{--no-grafts} option makes sure we get the exact same
10706 environment, with ungrafted packages (@pxref{Security Updates}, for more
10709 To get closer to a container like that used by the build daemon, we can
10710 remove @file{/bin/sh}:
10716 (Don't worry, this is harmless: this is all happening in the throw-away
10717 container created by @command{guix environment}.)
10719 The @command{strace} command is probably not in the search path, but we
10723 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
10726 In this way, not only you will have reproduced the environment variables
10727 the daemon uses, you will also be running the build process in a container
10728 similar to the one the daemon uses.
10731 @node Invoking guix edit
10732 @section Invoking @command{guix edit}
10734 @cindex @command{guix edit}
10735 @cindex package definition, editing
10736 So many packages, so many source files! The @command{guix edit} command
10737 facilitates the life of users and packagers by pointing their editor at
10738 the source file containing the definition of the specified packages.
10742 guix edit gcc@@4.9 vim
10746 launches the program specified in the @env{VISUAL} or in the
10747 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
10750 If you are using a Guix Git checkout (@pxref{Building from Git}), or
10751 have created your own packages on @env{GUIX_PACKAGE_PATH}
10752 (@pxref{Package Modules}), you will be able to edit the package
10753 recipes. In other cases, you will be able to examine the read-only recipes
10754 for packages currently in the store.
10756 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
10757 @option{--load-path=@var{directory}} (or in short @option{-L
10758 @var{directory}}) allows you to add @var{directory} to the front of the
10759 package module search path and so make your own packages visible.
10761 @node Invoking guix download
10762 @section Invoking @command{guix download}
10764 @cindex @command{guix download}
10765 @cindex downloading package sources
10766 When writing a package definition, developers typically need to download
10767 a source tarball, compute its SHA256 hash, and write that
10768 hash in the package definition (@pxref{Defining Packages}). The
10769 @command{guix download} tool helps with this task: it downloads a file
10770 from the given URI, adds it to the store, and prints both its file name
10771 in the store and its SHA256 hash.
10773 The fact that the downloaded file is added to the store saves bandwidth:
10774 when the developer eventually tries to build the newly defined package
10775 with @command{guix build}, the source tarball will not have to be
10776 downloaded again because it is already in the store. It is also a
10777 convenient way to temporarily stash files, which may be deleted
10778 eventually (@pxref{Invoking guix gc}).
10780 The @command{guix download} command supports the same URIs as used in
10781 package definitions. In particular, it supports @code{mirror://} URIs.
10782 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
10783 Guile bindings for GnuTLS are available in the user's environment; when
10784 they are not available, an error is raised. @xref{Guile Preparations,
10785 how to install the GnuTLS bindings for Guile,, gnutls-guile,
10786 GnuTLS-Guile}, for more information.
10788 @command{guix download} verifies HTTPS server certificates by loading
10789 the certificates of X.509 authorities from the directory pointed to by
10790 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
10791 Certificates}), unless @option{--no-check-certificate} is used.
10793 The following options are available:
10796 @item --hash=@var{algorithm}
10797 @itemx -H @var{algorithm}
10798 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
10799 hash}, for more information.
10801 @item --format=@var{fmt}
10802 @itemx -f @var{fmt}
10803 Write the hash in the format specified by @var{fmt}. For more
10804 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
10806 @item --no-check-certificate
10807 Do not validate the X.509 certificates of HTTPS servers.
10809 When using this option, you have @emph{absolutely no guarantee} that you
10810 are communicating with the authentic server responsible for the given
10811 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
10813 @item --output=@var{file}
10814 @itemx -o @var{file}
10815 Save the downloaded file to @var{file} instead of adding it to the
10819 @node Invoking guix hash
10820 @section Invoking @command{guix hash}
10822 @cindex @command{guix hash}
10823 The @command{guix hash} command computes the hash of a file.
10824 It is primarily a convenience tool for anyone contributing to the
10825 distribution: it computes the cryptographic hash of a file, which can be
10826 used in the definition of a package (@pxref{Defining Packages}).
10828 The general syntax is:
10831 guix hash @var{option} @var{file}
10834 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
10835 hash of data read from standard input. @command{guix hash} has the
10840 @item --hash=@var{algorithm}
10841 @itemx -H @var{algorithm}
10842 Compute a hash using the specified @var{algorithm}, @code{sha256} by
10845 @var{algorithm} must the name of a cryptographic hash algorithm
10846 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
10847 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
10848 Reference Manual}).
10850 @item --format=@var{fmt}
10851 @itemx -f @var{fmt}
10852 Write the hash in the format specified by @var{fmt}.
10854 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
10855 (@code{hex} and @code{hexadecimal} can be used as well).
10857 If the @option{--format} option is not specified, @command{guix hash}
10858 will output the hash in @code{nix-base32}. This representation is used
10859 in the definitions of packages.
10863 Compute the hash on @var{file} recursively.
10865 In this case, the hash is computed on an archive containing @var{file},
10866 including its children if it is a directory. Some of the metadata of
10867 @var{file} is part of the archive; for instance, when @var{file} is a
10868 regular file, the hash is different depending on whether @var{file} is
10869 executable or not. Metadata such as time stamps has no impact on the
10870 hash (@pxref{Invoking guix archive}).
10871 @c FIXME: Replace xref above with xref to an ``Archive'' section when
10874 @item --exclude-vcs
10876 When combined with @option{--recursive}, exclude version control system
10877 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
10880 As an example, here is how you would compute the hash of a Git checkout,
10881 which is useful when using the @code{git-fetch} method (@pxref{origin
10885 $ git clone http://example.org/foo.git
10891 @node Invoking guix import
10892 @section Invoking @command{guix import}
10894 @cindex importing packages
10895 @cindex package import
10896 @cindex package conversion
10897 @cindex Invoking @command{guix import}
10898 The @command{guix import} command is useful for people who would like to
10899 add a package to the distribution with as little work as
10900 possible---a legitimate demand. The command knows of a few
10901 repositories from which it can ``import'' package metadata. The result
10902 is a package definition, or a template thereof, in the format we know
10903 (@pxref{Defining Packages}).
10905 The general syntax is:
10908 guix import @var{importer} @var{options}@dots{}
10911 @var{importer} specifies the source from which to import package
10912 metadata, and @var{options} specifies a package identifier and other
10913 options specific to @var{importer}.
10915 Some of the importers rely on the ability to run the @command{gpgv} command.
10916 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
10919 Currently, the available ``importers'' are:
10923 Import metadata for the given GNU package. This provides a template
10924 for the latest version of that GNU package, including the hash of its
10925 source tarball, and its canonical synopsis and description.
10927 Additional information such as the package dependencies and its
10928 license needs to be figured out manually.
10930 For example, the following command returns a package definition for
10934 guix import gnu hello
10937 Specific command-line options are:
10940 @item --key-download=@var{policy}
10941 As for @command{guix refresh}, specify the policy to handle missing
10942 OpenPGP keys when verifying the package signature. @xref{Invoking guix
10943 refresh, @option{--key-download}}.
10948 Import metadata from the @uref{https://pypi.python.org/, Python Package
10949 Index}. Information is taken from the JSON-formatted description
10950 available at @code{pypi.python.org} and usually includes all the relevant
10951 information, including package dependencies. For maximum efficiency, it
10952 is recommended to install the @command{unzip} utility, so that the
10953 importer can unzip Python wheels and gather data from them.
10955 The command below imports metadata for the @code{itsdangerous} Python
10959 guix import pypi itsdangerous
10965 Traverse the dependency graph of the given upstream package recursively
10966 and generate package expressions for all those packages that are not yet
10972 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
10973 is taken from the JSON-formatted description available at
10974 @code{rubygems.org} and includes most relevant information, including
10975 runtime dependencies. There are some caveats, however. The metadata
10976 doesn't distinguish between synopses and descriptions, so the same string
10977 is used for both fields. Additionally, the details of non-Ruby
10978 dependencies required to build native extensions is unavailable and left
10979 as an exercise to the packager.
10981 The command below imports metadata for the @code{rails} Ruby package:
10984 guix import gem rails
10990 Traverse the dependency graph of the given upstream package recursively
10991 and generate package expressions for all those packages that are not yet
10997 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
10998 Information is taken from the JSON-formatted metadata provided through
10999 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
11000 relevant information, such as module dependencies. License information
11001 should be checked closely. If Perl is available in the store, then the
11002 @code{corelist} utility will be used to filter core modules out of the
11003 list of dependencies.
11005 The command command below imports metadata for the Acme::Boolean Perl
11009 guix import cpan Acme::Boolean
11014 @cindex Bioconductor
11015 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
11016 central repository for the @uref{https://r-project.org, GNU@tie{}R
11017 statistical and graphical environment}.
11019 Information is extracted from the @file{DESCRIPTION} file of the package.
11021 The command command below imports metadata for the Cairo R package:
11024 guix import cran Cairo
11027 When @option{--recursive} is added, the importer will traverse the
11028 dependency graph of the given upstream package recursively and generate
11029 package expressions for all those packages that are not yet in Guix.
11031 When @option{--style=specification} is added, the importer will generate
11032 package definitions whose inputs are package specifications instead of
11033 references to package variables. This is useful when generated package
11034 definitions are to be appended to existing user modules, as the list of
11035 used package modules need not be changed. The default is
11036 @option{--style=variable}.
11038 When @option{--archive=bioconductor} is added, metadata is imported from
11039 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
11040 packages for the analysis and comprehension of high-throughput
11041 genomic data in bioinformatics.
11043 Information is extracted from the @file{DESCRIPTION} file contained in the
11046 The command below imports metadata for the GenomicRanges R package:
11049 guix import cran --archive=bioconductor GenomicRanges
11052 Finally, you can also import R packages that have not yet been published on
11053 CRAN or Bioconductor as long as they are in a git repository. Use
11054 @option{--archive=git} followed by the URL of the git repository:
11057 guix import cran --archive=git https://github.com/immunogenomics/harmony
11063 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
11064 comprehensive TeX archive network for TeX packages that are part of the
11065 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
11067 Information about the package is obtained through the XML API provided
11068 by CTAN, while the source code is downloaded from the SVN repository of
11069 the Tex Live project. This is done because the CTAN does not keep
11070 versioned archives.
11072 The command command below imports metadata for the @code{fontspec}
11076 guix import texlive fontspec
11079 When @option{--archive=@var{directory}} is added, the source code is
11080 downloaded not from the @file{latex} sub-directory of the
11081 @file{texmf-dist/source} tree in the TeX Live SVN repository, but from
11082 the specified sibling @var{directory} under the same root.
11084 The command below imports metadata for the @code{ifxetex} package from
11085 CTAN while fetching the sources from the directory
11086 @file{texmf/source/generic}:
11089 guix import texlive --archive=generic ifxetex
11093 @cindex JSON, import
11094 Import package metadata from a local JSON file. Consider the following
11095 example package definition in JSON format:
11101 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
11102 "build-system": "gnu",
11103 "home-page": "https://www.gnu.org/software/hello/",
11104 "synopsis": "Hello, GNU world: An example GNU package",
11105 "description": "GNU Hello prints a greeting.",
11106 "license": "GPL-3.0+",
11107 "native-inputs": ["gettext"]
11111 The field names are the same as for the @code{<package>} record
11112 (@xref{Defining Packages}). References to other packages are provided
11113 as JSON lists of quoted package specification strings such as
11114 @code{guile} or @code{guile@@2.0}.
11116 The importer also supports a more explicit source definition using the
11117 common fields for @code{<origin>} records:
11123 "method": "url-fetch",
11124 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
11126 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
11133 The command below reads metadata from the JSON file @code{hello.json}
11134 and outputs a package expression:
11137 guix import json hello.json
11141 Import metadata from a local copy of the source of the
11142 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
11143 relies on the @command{nix-instantiate} command of
11144 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
11145 typically written in a mixture of Nix-language and Bash code. This
11146 command only imports the high-level package structure that is written in
11147 the Nix language. It normally includes all the basic fields of a
11148 package definition.
11150 When importing a GNU package, the synopsis and descriptions are replaced
11151 by their canonical upstream variant.
11153 Usually, you will first need to do:
11156 export NIX_REMOTE=daemon
11160 so that @command{nix-instantiate} does not try to open the Nix database.
11162 As an example, the command below imports the package definition of
11163 LibreOffice (more precisely, it imports the definition of the package
11164 bound to the @code{libreoffice} top-level attribute):
11167 guix import nix ~/path/to/nixpkgs libreoffice
11172 Import metadata from the Haskell community's central package archive
11173 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
11174 Cabal files and includes all the relevant information, including package
11177 Specific command-line options are:
11182 Read a Cabal file from standard input.
11183 @item --no-test-dependencies
11185 Do not include dependencies required only by the test suites.
11186 @item --cabal-environment=@var{alist}
11187 @itemx -e @var{alist}
11188 @var{alist} is a Scheme alist defining the environment in which the
11189 Cabal conditionals are evaluated. The accepted keys are: @code{os},
11190 @code{arch}, @code{impl} and a string representing the name of a flag.
11191 The value associated with a flag has to be either the symbol
11192 @code{true} or @code{false}. The value associated with other keys
11193 has to conform to the Cabal file format definition. The default value
11194 associated with the keys @code{os}, @code{arch} and @code{impl} is
11195 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
11198 Traverse the dependency graph of the given upstream package recursively
11199 and generate package expressions for all those packages that are not yet
11203 The command below imports metadata for the latest version of the
11204 HTTP Haskell package without including test dependencies and
11205 specifying the value of the flag @samp{network-uri} as @code{false}:
11208 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
11211 A specific package version may optionally be specified by following the
11212 package name by an at-sign and a version number as in the following example:
11215 guix import hackage mtl@@2.1.3.1
11220 The @code{stackage} importer is a wrapper around the @code{hackage} one.
11221 It takes a package name, looks up the package version included in a
11222 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
11223 release and uses the @code{hackage} importer to retrieve its metadata.
11224 Note that it is up to you to select an LTS release compatible with the
11225 GHC compiler used by Guix.
11227 Specific command-line options are:
11230 @item --no-test-dependencies
11232 Do not include dependencies required only by the test suites.
11233 @item --lts-version=@var{version}
11234 @itemx -l @var{version}
11235 @var{version} is the desired LTS release version. If omitted the latest
11239 Traverse the dependency graph of the given upstream package recursively
11240 and generate package expressions for all those packages that are not yet
11244 The command below imports metadata for the HTTP Haskell package
11245 included in the LTS Stackage release version 7.18:
11248 guix import stackage --lts-version=7.18 HTTP
11253 Import metadata from an Emacs Lisp Package Archive (ELPA) package
11254 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
11256 Specific command-line options are:
11259 @item --archive=@var{repo}
11260 @itemx -a @var{repo}
11261 @var{repo} identifies the archive repository from which to retrieve the
11262 information. Currently the supported repositories and their identifiers
11266 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
11267 identifier. This is the default.
11269 Packages from @code{elpa.gnu.org} are signed with one of the keys
11270 contained in the GnuPG keyring at
11271 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
11272 @code{emacs} package (@pxref{Package Installation, ELPA package
11273 signatures,, emacs, The GNU Emacs Manual}).
11276 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
11277 @code{melpa-stable} identifier.
11280 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
11286 Traverse the dependency graph of the given upstream package recursively
11287 and generate package expressions for all those packages that are not yet
11293 Import metadata from the crates.io Rust package repository
11294 @uref{https://crates.io, crates.io}, as in this example:
11297 guix import crate blake2-rfc
11300 The crate importer also allows you to specify a version string:
11303 guix import crate constant-time-eq@@0.1.0
11306 Additional options include:
11311 Traverse the dependency graph of the given upstream package recursively
11312 and generate package expressions for all those packages that are not yet
11319 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
11320 repository used by the OCaml community.
11322 Additional options include:
11327 Traverse the dependency graph of the given upstream package recursively
11328 and generate package expressions for all those packages that are not yet
11331 Select the given repository (a repository name). Possible values include:
11333 @item @code{opam}, the default opam repository,
11334 @item @code{coq} or @code{coq-released}, the stable repository for coq packages,
11335 @item @code{coq-core-dev}, the repository that contains development versions of coq,
11336 @item @code{coq-extra-dev}, the repository that contains development versions
11342 The structure of the @command{guix import} code is modular. It would be
11343 useful to have more importers for other package formats, and your help
11344 is welcome here (@pxref{Contributing}).
11346 @node Invoking guix refresh
11347 @section Invoking @command{guix refresh}
11349 @cindex @command {guix refresh}
11350 The primary audience of the @command{guix refresh} command is developers
11351 of the GNU software distribution. By default, it reports any packages
11352 provided by the distribution that are outdated compared to the latest
11353 upstream version, like this:
11357 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
11358 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
11361 Alternatively, one can specify packages to consider, in which case a
11362 warning is emitted for packages that lack an updater:
11365 $ guix refresh coreutils guile guile-ssh
11366 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
11367 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
11370 @command{guix refresh} browses the upstream repository of each package and determines
11371 the highest version number of the releases therein. The command
11372 knows how to update specific types of packages: GNU packages, ELPA
11373 packages, etc.---see the documentation for @option{--type} below. There
11374 are many packages, though, for which it lacks a method to determine
11375 whether a new upstream release is available. However, the mechanism is
11376 extensible, so feel free to get in touch with us to add a new method!
11381 Consider the packages specified, and all the packages upon which they depend.
11384 $ guix refresh --recursive coreutils
11385 gnu/packages/acl.scm:35:2: warning: no updater for acl
11386 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
11387 gnu/packages/xml.scm:68:2: warning: no updater for expat
11388 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
11394 Sometimes the upstream name differs from the package name used in Guix,
11395 and @command{guix refresh} needs a little help. Most updaters honor the
11396 @code{upstream-name} property in package definitions, which can be used
11400 (define-public network-manager
11402 (name "network-manager")
11404 (properties '((upstream-name . "NetworkManager")))))
11407 When passed @option{--update}, it modifies distribution source files to
11408 update the version numbers and source tarball hashes of those package
11409 recipes (@pxref{Defining Packages}). This is achieved by downloading
11410 each package's latest source tarball and its associated OpenPGP
11411 signature, authenticating the downloaded tarball against its signature
11412 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
11413 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
11416 key used to sign the tarball is missing from the user's keyring, an
11417 attempt is made to automatically retrieve it from a public key server;
11418 when this is successful, the key is added to the user's keyring; otherwise,
11419 @command{guix refresh} reports an error.
11421 The following options are supported:
11425 @item --expression=@var{expr}
11426 @itemx -e @var{expr}
11427 Consider the package @var{expr} evaluates to.
11429 This is useful to precisely refer to a package, as in this example:
11432 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
11435 This command lists the dependents of the ``final'' libc (essentially all
11440 Update distribution source files (package recipes) in place. This is
11441 usually run from a checkout of the Guix source tree (@pxref{Running
11442 Guix Before It Is Installed}):
11445 $ ./pre-inst-env guix refresh -s non-core -u
11448 @xref{Defining Packages}, for more information on package definitions.
11450 @item --select=[@var{subset}]
11451 @itemx -s @var{subset}
11452 Select all the packages in @var{subset}, one of @code{core} or
11455 The @code{core} subset refers to all the packages at the core of the
11456 distribution---i.e., packages that are used to build ``everything
11457 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
11458 changing one of these packages in the distribution entails a rebuild of
11459 all the others. Thus, such updates are an inconvenience to users in
11460 terms of build time or bandwidth used to achieve the upgrade.
11462 The @code{non-core} subset refers to the remaining packages. It is
11463 typically useful in cases where an update of the core packages would be
11466 @item --manifest=@var{file}
11467 @itemx -m @var{file}
11468 Select all the packages from the manifest in @var{file}. This is useful to
11469 check if any packages of the user manifest can be updated.
11471 @item --type=@var{updater}
11472 @itemx -t @var{updater}
11473 Select only packages handled by @var{updater} (may be a comma-separated
11474 list of updaters). Currently, @var{updater} may be one of:
11478 the updater for GNU packages;
11480 the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
11482 the updater for GNOME packages;
11484 the updater for KDE packages;
11486 the updater for X.org packages;
11488 the updater for packages hosted on kernel.org;
11490 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
11492 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
11494 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
11496 the updater for @uref{https://www.cpan.org/, CPAN} packages;
11498 the updater for @uref{https://pypi.python.org, PyPI} packages.
11500 the updater for @uref{https://rubygems.org, RubyGems} packages.
11502 the updater for @uref{https://github.com, GitHub} packages.
11504 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
11506 the updater for @uref{https://www.stackage.org, Stackage} packages.
11508 the updater for @uref{https://crates.io, Crates} packages.
11510 the updater for @uref{https://launchpad.net, Launchpad} packages.
11513 For instance, the following command only checks for updates of Emacs
11514 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
11517 $ guix refresh --type=elpa,cran
11518 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
11519 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
11524 In addition, @command{guix refresh} can be passed one or more package
11525 names, as in this example:
11528 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
11532 The command above specifically updates the @code{emacs} and
11533 @code{idutils} packages. The @option{--select} option would have no
11534 effect in this case.
11536 When considering whether to upgrade a package, it is sometimes
11537 convenient to know which packages would be affected by the upgrade and
11538 should be checked for compatibility. For this the following option may
11539 be used when passing @command{guix refresh} one or more package names:
11543 @item --list-updaters
11545 List available updaters and exit (see @option{--type} above).
11547 For each updater, display the fraction of packages it covers; at the
11548 end, display the fraction of packages covered by all these updaters.
11550 @item --list-dependent
11552 List top-level dependent packages that would need to be rebuilt as a
11553 result of upgrading one or more packages.
11555 @xref{Invoking guix graph, the @code{reverse-package} type of
11556 @command{guix graph}}, for information on how to visualize the list of
11557 dependents of a package.
11561 Be aware that the @option{--list-dependent} option only
11562 @emph{approximates} the rebuilds that would be required as a result of
11563 an upgrade. More rebuilds might be required under some circumstances.
11566 $ guix refresh --list-dependent flex
11567 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
11568 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
11571 The command above lists a set of packages that could be built to check
11572 for compatibility with an upgraded @code{flex} package.
11576 @item --list-transitive
11577 List all the packages which one or more packages depend upon.
11580 $ guix refresh --list-transitive flex
11581 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
11582 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{}
11587 The command above lists a set of packages which, when changed, would cause
11588 @code{flex} to be rebuilt.
11590 The following options can be used to customize GnuPG operation:
11594 @item --gpg=@var{command}
11595 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
11596 for in @code{$PATH}.
11598 @item --keyring=@var{file}
11599 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
11600 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
11601 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
11602 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
11603 information on a tool to manipulate keybox files).
11605 When this option is omitted, @command{guix refresh} uses
11606 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
11607 signing keys. OpenPGP signatures are checked against keys from this keyring;
11608 missing keys are downloaded to this keyring as well (see
11609 @option{--key-download} below).
11611 You can export keys from your default GPG keyring into a keybox file using
11612 commands like this one:
11615 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
11618 Likewise, you can fetch keys to a specific keybox file like this:
11621 gpg --no-default-keyring --keyring mykeyring.kbx \
11622 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
11625 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
11626 Privacy Guard}, for more information on GPG's @option{--keyring} option.
11628 @item --key-download=@var{policy}
11629 Handle missing OpenPGP keys according to @var{policy}, which may be one
11634 Always download missing OpenPGP keys from the key server, and add them
11635 to the user's GnuPG keyring.
11638 Never try to download missing OpenPGP keys. Instead just bail out.
11641 When a package signed with an unknown OpenPGP key is encountered, ask
11642 the user whether to download it or not. This is the default behavior.
11645 @item --key-server=@var{host}
11646 Use @var{host} as the OpenPGP key server when importing a public key.
11648 @item --load-path=@var{directory}
11649 Add @var{directory} to the front of the package module search path
11650 (@pxref{Package Modules}).
11652 This allows users to define their own packages and make them visible to
11653 the command-line tools.
11657 The @code{github} updater uses the
11658 @uref{https://developer.github.com/v3/, GitHub API} to query for new
11659 releases. When used repeatedly e.g.@: when refreshing all packages,
11660 GitHub will eventually refuse to answer any further API requests. By
11661 default 60 API requests per hour are allowed, and a full refresh on all
11662 GitHub packages in Guix requires more than this. Authentication with
11663 GitHub through the use of an API token alleviates these limits. To use
11664 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
11665 token procured from @uref{https://github.com/settings/tokens} or
11669 @node Invoking guix lint
11670 @section Invoking @command{guix lint}
11672 @cindex @command{guix lint}
11673 @cindex package, checking for errors
11674 The @command{guix lint} command is meant to help package developers avoid
11675 common errors and use a consistent style. It runs a number of checks on
11676 a given set of packages in order to find common mistakes in their
11677 definitions. Available @dfn{checkers} include (see
11678 @option{--list-checkers} for a complete list):
11683 Validate certain typographical and stylistic rules about package
11684 descriptions and synopses.
11686 @item inputs-should-be-native
11687 Identify inputs that should most likely be native inputs.
11693 @itemx source-file-name
11694 Probe @code{home-page} and @code{source} URLs and report those that are
11695 invalid. Suggest a @code{mirror://} URL when applicable. If the
11696 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
11697 URL. Check that the source file name is meaningful, e.g.@: is not just a
11698 version number or ``git-checkout'', without a declared @code{file-name}
11699 (@pxref{origin Reference}).
11701 @item source-unstable-tarball
11702 Parse the @code{source} URL to determine if a tarball from GitHub is
11703 autogenerated or if it is a release tarball. Unfortunately GitHub's
11704 autogenerated tarballs are sometimes regenerated.
11707 Check that the derivation of the given packages can be successfully
11708 computed for all the supported systems (@pxref{Derivations}).
11710 @item profile-collisions
11711 Check whether installing the given packages in a profile would lead to
11712 collisions. Collisions occur when several packages with the same name
11713 but a different version or a different store file name are propagated.
11714 @xref{package Reference, @code{propagated-inputs}}, for more information
11715 on propagated inputs.
11718 @cindex Software Heritage, source code archive
11719 @cindex archival of source code, Software Heritage
11720 Checks whether the package's source code is archived at
11721 @uref{https://www.softwareheritage.org, Software Heritage}.
11723 When the source code that is not archived comes from a version-control system
11724 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
11725 ``save'' request so that it eventually archives it. This ensures that the
11726 source will remain available in the long term, and that Guix can fall back to
11727 Software Heritage should the source code disappear from its original host.
11728 The status of recent ``save'' requests can be
11729 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
11731 When source code is a tarball obtained with @code{url-fetch}, simply print a
11732 message when it is not archived. As of this writing, Software Heritage does
11733 not allow requests to save arbitrary tarballs; we are working on ways to
11734 ensure that non-VCS source code is also archived.
11737 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
11738 request rate per IP address}. When the limit is reached, @command{guix lint}
11739 prints a message and the @code{archival} checker stops doing anything until
11740 that limit has been reset.
11743 @cindex security vulnerabilities
11744 @cindex CVE, Common Vulnerabilities and Exposures
11745 Report known vulnerabilities found in the Common Vulnerabilities and
11746 Exposures (CVE) databases of the current and past year
11747 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
11750 To view information about a particular vulnerability, visit pages such as:
11754 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
11756 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
11760 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
11761 @code{CVE-2015-7554}.
11763 Package developers can specify in package recipes the
11764 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
11765 name and version of the package when they differ from the name or version
11766 that Guix uses, as in this example:
11772 ;; CPE calls this package "grub2".
11773 (properties '((cpe-name . "grub2")
11774 (cpe-version . "2.3"))))
11777 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
11778 Some entries in the CVE database do not specify which version of a
11779 package they apply to, and would thus ``stick around'' forever. Package
11780 developers who found CVE alerts and verified they can be ignored can
11781 declare them as in this example:
11787 ;; These CVEs no longer apply and can be safely ignored.
11788 (properties `((lint-hidden-cve . ("CVE-2011-0433"
11791 "CVE-2011-5244")))))
11795 Warn about obvious source code formatting issues: trailing white space,
11796 use of tabulations, etc.
11799 The general syntax is:
11802 guix lint @var{options} @var{package}@dots{}
11805 If no package is given on the command line, then all packages are checked.
11806 The @var{options} may be zero or more of the following:
11809 @item --list-checkers
11811 List and describe all the available checkers that will be run on packages
11816 Only enable the checkers specified in a comma-separated list using the
11817 names returned by @option{--list-checkers}.
11821 Only disable the checkers specified in a comma-separated list using the
11822 names returned by @option{--list-checkers}.
11826 Only enable the checkers that do not depend on Internet access.
11828 @item --load-path=@var{directory}
11829 @itemx -L @var{directory}
11830 Add @var{directory} to the front of the package module search path
11831 (@pxref{Package Modules}).
11833 This allows users to define their own packages and make them visible to
11834 the command-line tools.
11838 @node Invoking guix size
11839 @section Invoking @command{guix size}
11842 @cindex package size
11844 @cindex @command{guix size}
11845 The @command{guix size} command helps package developers profile the
11846 disk usage of packages. It is easy to overlook the impact of an
11847 additional dependency added to a package, or the impact of using a
11848 single output for a package that could easily be split (@pxref{Packages
11849 with Multiple Outputs}). Such are the typical issues that
11850 @command{guix size} can highlight.
11852 The command can be passed one or more package specifications
11853 such as @code{gcc@@4.8}
11854 or @code{guile:debug}, or a file name in the store. Consider this
11858 $ guix size coreutils
11859 store item total self
11860 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
11861 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
11862 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
11863 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
11864 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
11865 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
11866 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
11867 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
11872 The store items listed here constitute the @dfn{transitive closure} of
11873 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
11874 would be returned by:
11877 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
11880 Here the output shows three columns next to store items. The first column,
11881 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
11882 the store item---that is, its own size plus the size of all its
11883 dependencies. The next column, labeled ``self'', shows the size of the
11884 item itself. The last column shows the ratio of the size of the item
11885 itself to the space occupied by all the items listed here.
11887 In this example, we see that the closure of Coreutils weighs in at
11888 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
11889 libraries. (That libc and GCC's libraries represent a large fraction of
11890 the closure is not a problem @i{per se} because they are always available
11891 on the system anyway.)
11893 Since the command also accepts store file names, assessing the size of
11894 a build result is straightforward:
11897 guix size $(guix system build config.scm)
11900 When the package(s) passed to @command{guix size} are available in the
11901 store@footnote{More precisely, @command{guix size} looks for the
11902 @emph{ungrafted} variant of the given package(s), as returned by
11903 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
11904 for information on grafts.}, @command{guix size} queries the daemon to determine its
11905 dependencies, and measures its size in the store, similar to @command{du
11906 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
11909 When the given packages are @emph{not} in the store, @command{guix size}
11910 reports information based on the available substitutes
11911 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
11912 store items that are not even on disk, only available remotely.
11914 You can also specify several package names:
11917 $ guix size coreutils grep sed bash
11918 store item total self
11919 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
11920 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
11921 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
11922 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
11928 In this example we see that the combination of the four packages takes
11929 102.3@tie{}MiB in total, which is much less than the sum of each closure
11930 since they have a lot of dependencies in common.
11932 When looking at the profile returned by @command{guix size}, you may
11933 find yourself wondering why a given package shows up in the profile at
11934 all. To understand it, you can use @command{guix graph --path -t
11935 references} to display the shortest path between the two packages
11936 (@pxref{Invoking guix graph}).
11938 The available options are:
11942 @item --substitute-urls=@var{urls}
11943 Use substitute information from @var{urls}.
11944 @xref{client-substitute-urls, the same option for @code{guix build}}.
11946 @item --sort=@var{key}
11947 Sort lines according to @var{key}, one of the following options:
11951 the size of each item (the default);
11953 the total size of the item's closure.
11956 @item --map-file=@var{file}
11957 Write a graphical map of disk usage in PNG format to @var{file}.
11959 For the example above, the map looks like this:
11961 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
11962 produced by @command{guix size}}
11964 This option requires that
11965 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
11966 installed and visible in Guile's module search path. When that is not
11967 the case, @command{guix size} fails as it tries to load it.
11969 @item --system=@var{system}
11970 @itemx -s @var{system}
11971 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
11973 @item --load-path=@var{directory}
11974 @itemx -L @var{directory}
11975 Add @var{directory} to the front of the package module search path
11976 (@pxref{Package Modules}).
11978 This allows users to define their own packages and make them visible to
11979 the command-line tools.
11982 @node Invoking guix graph
11983 @section Invoking @command{guix graph}
11986 @cindex @command{guix graph}
11987 @cindex package dependencies
11988 Packages and their dependencies form a @dfn{graph}, specifically a
11989 directed acyclic graph (DAG). It can quickly become difficult to have a
11990 mental model of the package DAG, so the @command{guix graph} command
11991 provides a visual representation of the DAG. By default,
11992 @command{guix graph} emits a DAG representation in the input format of
11993 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
11994 directly to the @command{dot} command of Graphviz. It can also emit an
11995 HTML page with embedded JavaScript code to display a ``chord diagram''
11996 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
11997 emit Cypher queries to construct a graph in a graph database supporting
11998 the @uref{https://www.opencypher.org/, openCypher} query language. With
11999 @option{--path}, it simply displays the shortest path between two
12000 packages. The general syntax is:
12003 guix graph @var{options} @var{package}@dots{}
12006 For example, the following command generates a PDF file representing the
12007 package DAG for the GNU@tie{}Core Utilities, showing its build-time
12011 guix graph coreutils | dot -Tpdf > dag.pdf
12014 The output looks like this:
12016 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
12018 Nice little graph, no?
12020 You may find it more pleasant to navigate the graph interactively with
12021 @command{xdot} (from the @code{xdot} package):
12024 guix graph coreutils | xdot -
12027 But there is more than one graph! The one above is concise: it is the
12028 graph of package objects, omitting implicit inputs such as GCC, libc,
12029 grep, etc. It is often useful to have such a concise graph, but
12030 sometimes one may want to see more details. @command{guix graph} supports
12031 several types of graphs, allowing you to choose the level of detail:
12035 This is the default type used in the example above. It shows the DAG of
12036 package objects, excluding implicit dependencies. It is concise, but
12037 filters out many details.
12039 @item reverse-package
12040 This shows the @emph{reverse} DAG of packages. For example:
12043 guix graph --type=reverse-package ocaml
12046 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
12047 you are also interested in cases where OCaml is an implicit dependency, see
12048 @code{reverse-bag} below).
12050 Note that for core packages this can yield huge graphs. If all you want
12051 is to know the number of packages that depend on a given package, use
12052 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
12053 @option{--list-dependent}}).
12056 This is the package DAG, @emph{including} implicit inputs.
12058 For instance, the following command:
12061 guix graph --type=bag-emerged coreutils
12064 ...@: yields this bigger graph:
12066 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
12068 At the bottom of the graph, we see all the implicit inputs of
12069 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
12071 Now, note that the dependencies of these implicit inputs---that is, the
12072 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
12073 here, for conciseness.
12076 Similar to @code{bag-emerged}, but this time including all the bootstrap
12079 @item bag-with-origins
12080 Similar to @code{bag}, but also showing origins and their dependencies.
12083 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
12084 it also takes implicit dependencies into account. For example:
12087 guix graph -t reverse-bag dune
12091 ...@: yields the graph of all packages that depend on Dune, directly or
12092 indirectly. Since Dune is an @emph{implicit} dependency of many packages
12093 @i{via} @code{dune-build-system}, this shows a large number of packages,
12094 whereas @code{reverse-package} would show very few if any.
12097 This is the most detailed representation: It shows the DAG of
12098 derivations (@pxref{Derivations}) and plain store items. Compared to
12099 the above representation, many additional nodes are visible, including
12100 build scripts, patches, Guile modules, etc.
12102 For this type of graph, it is also possible to pass a @file{.drv} file
12103 name instead of a package name, as in:
12106 guix graph -t derivation `guix system build -d my-config.scm`
12110 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
12111 For example, the following command shows the graph for the package
12112 module that defines the @code{guile} package:
12115 guix graph -t module guile | xdot -
12119 All the types above correspond to @emph{build-time dependencies}. The
12120 following graph type represents the @emph{run-time dependencies}:
12124 This is the graph of @dfn{references} of a package output, as returned
12125 by @command{guix gc --references} (@pxref{Invoking guix gc}).
12127 If the given package output is not available in the store, @command{guix
12128 graph} attempts to obtain dependency information from substitutes.
12130 Here you can also pass a store file name instead of a package name. For
12131 example, the command below produces the reference graph of your profile
12132 (which can be big!):
12135 guix graph -t references `readlink -f ~/.guix-profile`
12139 This is the graph of the @dfn{referrers} of a store item, as returned by
12140 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
12142 This relies exclusively on local information from your store. For
12143 instance, let us suppose that the current Inkscape is available in 10
12144 profiles on your machine; @command{guix graph -t referrers inkscape}
12145 will show a graph rooted at Inkscape and with those 10 profiles linked
12148 It can help determine what is preventing a store item from being garbage
12153 @cindex shortest path, between packages
12154 Often, the graph of the package you are interested in does not fit on
12155 your screen, and anyway all you want to know is @emph{why} that package
12156 actually depends on some seemingly unrelated package. The
12157 @option{--path} option instructs @command{guix graph} to display the
12158 shortest path between two packages (or derivations, or store items,
12162 $ guix graph --path emacs libunistring
12165 libunistring@@0.9.10
12166 $ guix graph --path -t derivation emacs libunistring
12167 /gnu/store/@dots{}-emacs-26.3.drv
12168 /gnu/store/@dots{}-mailutils-3.9.drv
12169 /gnu/store/@dots{}-libunistring-0.9.10.drv
12170 $ guix graph --path -t references emacs libunistring
12171 /gnu/store/@dots{}-emacs-26.3
12172 /gnu/store/@dots{}-libidn2-2.2.0
12173 /gnu/store/@dots{}-libunistring-0.9.10
12176 The available options are the following:
12179 @item --type=@var{type}
12180 @itemx -t @var{type}
12181 Produce a graph output of @var{type}, where @var{type} must be one of
12182 the values listed above.
12185 List the supported graph types.
12187 @item --backend=@var{backend}
12188 @itemx -b @var{backend}
12189 Produce a graph using the selected @var{backend}.
12191 @item --list-backends
12192 List the supported graph backends.
12194 Currently, the available backends are Graphviz and d3.js.
12197 Display the shortest path between two nodes of the type specified by
12198 @option{--type}. The example below shows the shortest path between
12199 @code{libreoffice} and @code{llvm} according to the references of
12200 @code{libreoffice}:
12203 $ guix graph --path -t references libreoffice llvm
12204 /gnu/store/@dots{}-libreoffice-6.4.2.2
12205 /gnu/store/@dots{}-libepoxy-1.5.4
12206 /gnu/store/@dots{}-mesa-19.3.4
12207 /gnu/store/@dots{}-llvm-9.0.1
12210 @item --expression=@var{expr}
12211 @itemx -e @var{expr}
12212 Consider the package @var{expr} evaluates to.
12214 This is useful to precisely refer to a package, as in this example:
12217 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
12220 @item --system=@var{system}
12221 @itemx -s @var{system}
12222 Display the graph for @var{system}---e.g., @code{i686-linux}.
12224 The package dependency graph is largely architecture-independent, but there
12225 are some architecture-dependent bits that this option allows you to visualize.
12227 @item --load-path=@var{directory}
12228 @itemx -L @var{directory}
12229 Add @var{directory} to the front of the package module search path
12230 (@pxref{Package Modules}).
12232 This allows users to define their own packages and make them visible to
12233 the command-line tools.
12236 On top of that, @command{guix graph} supports all the usual package
12237 transformation options (@pxref{Package Transformation Options}). This
12238 makes it easy to view the effect of a graph-rewriting transformation
12239 such as @option{--with-input}. For example, the command below outputs
12240 the graph of @code{git} once @code{openssl} has been replaced by
12241 @code{libressl} everywhere in the graph:
12244 guix graph git --with-input=openssl=libressl
12247 So many possibilities, so much fun!
12249 @node Invoking guix publish
12250 @section Invoking @command{guix publish}
12252 @cindex @command{guix publish}
12253 The purpose of @command{guix publish} is to enable users to easily share
12254 their store with others, who can then use it as a substitute server
12255 (@pxref{Substitutes}).
12257 When @command{guix publish} runs, it spawns an HTTP server which allows
12258 anyone with network access to obtain substitutes from it. This means
12259 that any machine running Guix can also act as if it were a build farm,
12260 since the HTTP interface is compatible with Cuirass, the software behind
12261 the @code{@value{SUBSTITUTE-SERVER}} build farm.
12263 For security, each substitute is signed, allowing recipients to check
12264 their authenticity and integrity (@pxref{Substitutes}). Because
12265 @command{guix publish} uses the signing key of the system, which is only
12266 readable by the system administrator, it must be started as root; the
12267 @option{--user} option makes it drop root privileges early on.
12269 The signing key pair must be generated before @command{guix publish} is
12270 launched, using @command{guix archive --generate-key} (@pxref{Invoking
12273 When the @option{--advertise} option is passed, the server advertises
12274 its availability on the local network using multicast DNS (mDNS) and DNS
12275 service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
12276 guile-avahi, Using Avahi in Guile Scheme Programs}).
12278 The general syntax is:
12281 guix publish @var{options}@dots{}
12284 Running @command{guix publish} without any additional arguments will
12285 spawn an HTTP server on port 8080:
12291 Once a publishing server has been authorized, the daemon may download
12292 substitutes from it. @xref{Getting Substitutes from Other Servers}.
12294 By default, @command{guix publish} compresses archives on the fly as it
12295 serves them. This ``on-the-fly'' mode is convenient in that it requires
12296 no setup and is immediately available. However, when serving lots of
12297 clients, we recommend using the @option{--cache} option, which enables
12298 caching of the archives before they are sent to clients---see below for
12299 details. The @command{guix weather} command provides a handy way to
12300 check what a server provides (@pxref{Invoking guix weather}).
12302 As a bonus, @command{guix publish} also serves as a content-addressed
12303 mirror for source files referenced in @code{origin} records
12304 (@pxref{origin Reference}). For instance, assuming @command{guix
12305 publish} is running on @code{example.org}, the following URL returns the
12306 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
12307 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
12310 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
12313 Obviously, these URLs only work for files that are in the store; in
12314 other cases, they return 404 (``Not Found'').
12316 @cindex build logs, publication
12317 Build logs are available from @code{/log} URLs like:
12320 http://example.org/log/gwspk@dots{}-guile-2.2.3
12324 When @command{guix-daemon} is configured to save compressed build logs,
12325 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
12326 URLs return the compressed log as-is, with an appropriate
12327 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
12328 running @command{guix-daemon} with @option{--log-compression=gzip} since
12329 Web browsers can automatically decompress it, which is not the case with
12332 The following options are available:
12335 @item --port=@var{port}
12336 @itemx -p @var{port}
12337 Listen for HTTP requests on @var{port}.
12339 @item --listen=@var{host}
12340 Listen on the network interface for @var{host}. The default is to
12341 accept connections from any interface.
12343 @item --user=@var{user}
12344 @itemx -u @var{user}
12345 Change privileges to @var{user} as soon as possible---i.e., once the
12346 server socket is open and the signing key has been read.
12348 @item --compression[=@var{method}[:@var{level}]]
12349 @itemx -C [@var{method}[:@var{level}]]
12350 Compress data using the given @var{method} and @var{level}. @var{method} is
12351 one of @code{lzip}, @code{zstd}, and @code{gzip}; when @var{method} is
12352 omitted, @code{gzip} is used.
12354 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
12355 to different compression levels: 1 is the fastest, and 9 is the best
12356 (CPU-intensive). The default is 3.
12358 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a
12359 small increase in CPU usage; see
12360 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip
12361 Web page}. However, @code{lzip} achieves low decompression throughput
12362 (on the order of 50@tie{}MiB/s on modern hardware), which can be a
12363 bottleneck for someone who downloads over a fast network connection.
12365 The compression ratio of @code{zstd} is between that of @code{lzip} and
12366 that of @code{gzip}; its main advantage is a
12367 @uref{https://facebook.github.io/zstd/,high decompression speed}.
12369 Unless @option{--cache} is used, compression occurs on the fly and
12370 the compressed streams are not
12371 cached. Thus, to reduce load on the machine that runs @command{guix
12372 publish}, it may be a good idea to choose a low compression level, to
12373 run @command{guix publish} behind a caching proxy, or to use
12374 @option{--cache}. Using @option{--cache} has the advantage that it
12375 allows @command{guix publish} to add @code{Content-Length} HTTP header
12378 This option can be repeated, in which case every substitute gets compressed
12379 using all the selected methods, and all of them are advertised. This is
12380 useful when users may not support all the compression methods: they can select
12381 the one they support.
12383 @item --cache=@var{directory}
12384 @itemx -c @var{directory}
12385 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
12386 and only serve archives that are in cache.
12388 When this option is omitted, archives and meta-data are created
12389 on-the-fly. This can reduce the available bandwidth, especially when
12390 compression is enabled, since this may become CPU-bound. Another
12391 drawback of the default mode is that the length of archives is not known
12392 in advance, so @command{guix publish} does not add a
12393 @code{Content-Length} HTTP header to its responses, which in turn
12394 prevents clients from knowing the amount of data being downloaded.
12396 Conversely, when @option{--cache} is used, the first request for a store
12397 item (@i{via} a @code{.narinfo} URL) triggers a
12398 background process to @dfn{bake} the archive---computing its
12399 @code{.narinfo} and compressing the archive, if needed. Once the
12400 archive is cached in @var{directory}, subsequent requests succeed and
12401 are served directly from the cache, which guarantees that clients get
12402 the best possible bandwidth.
12404 That first @code{.narinfo} request nonetheless returns 200, provided the
12405 requested store item is ``small enough'', below the cache bypass
12406 threshold---see @option{--cache-bypass-threshold} below. That way,
12407 clients do not have to wait until the archive is baked. For larger
12408 store items, the first @code{.narinfo} request returns 404, meaning that
12409 clients have to wait until the archive is baked.
12411 The ``baking'' process is performed by worker threads. By default, one
12412 thread per CPU core is created, but this can be customized. See
12413 @option{--workers} below.
12415 When @option{--ttl} is used, cached entries are automatically deleted
12416 when they have expired.
12418 @item --workers=@var{N}
12419 When @option{--cache} is used, request the allocation of @var{N} worker
12420 threads to ``bake'' archives.
12422 @item --ttl=@var{ttl}
12423 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
12424 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
12425 days, @code{1m} means 1 month, and so on.
12427 This allows the user's Guix to keep substitute information in cache for
12428 @var{ttl}. However, note that @code{guix publish} does not itself
12429 guarantee that the store items it provides will indeed remain available
12430 for as long as @var{ttl}.
12432 Additionally, when @option{--cache} is used, cached entries that have
12433 not been accessed for @var{ttl} and that no longer have a corresponding
12434 item in the store, may be deleted.
12436 @item --cache-bypass-threshold=@var{size}
12437 When used in conjunction with @option{--cache}, store items smaller than
12438 @var{size} are immediately available, even when they are not yet in
12439 cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
12440 for megabytes and so on. The default is @code{10M}.
12442 ``Cache bypass'' allows you to reduce the publication delay for clients
12443 at the expense of possibly additional I/O and CPU use on the server
12444 side: depending on the client access patterns, those store items can end
12445 up being baked several times until a copy is available in cache.
12447 Increasing the threshold may be useful for sites that have few users, or
12448 to guarantee that users get substitutes even for store items that are
12451 @item --nar-path=@var{path}
12452 Use @var{path} as the prefix for the URLs of ``nar'' files
12453 (@pxref{Invoking guix archive, normalized archives}).
12455 By default, nars are served at a URL such as
12456 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
12457 change the @code{/nar} part to @var{path}.
12459 @item --public-key=@var{file}
12460 @itemx --private-key=@var{file}
12461 Use the specific @var{file}s as the public/private key pair used to sign
12462 the store items being published.
12464 The files must correspond to the same key pair (the private key is used
12465 for signing and the public key is merely advertised in the signature
12466 metadata). They must contain keys in the canonical s-expression format
12467 as produced by @command{guix archive --generate-key} (@pxref{Invoking
12468 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
12469 @file{/etc/guix/signing-key.sec} are used.
12471 @item --repl[=@var{port}]
12472 @itemx -r [@var{port}]
12473 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
12474 Reference Manual}) on @var{port} (37146 by default). This is used
12475 primarily for debugging a running @command{guix publish} server.
12478 Enabling @command{guix publish} on Guix System is a one-liner: just
12479 instantiate a @code{guix-publish-service-type} service in the @code{services} field
12480 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
12481 @code{guix-publish-service-type}}).
12483 If you are instead running Guix on a ``foreign distro'', follow these
12488 If your host distro uses the systemd init system:
12491 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
12492 /etc/systemd/system/
12493 # systemctl start guix-publish && systemctl enable guix-publish
12497 If your host distro uses the Upstart init system:
12500 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
12501 # start guix-publish
12505 Otherwise, proceed similarly with your distro's init system.
12508 @node Invoking guix challenge
12509 @section Invoking @command{guix challenge}
12511 @cindex reproducible builds
12512 @cindex verifiable builds
12513 @cindex @command{guix challenge}
12515 Do the binaries provided by this server really correspond to the source
12516 code it claims to build? Is a package build process deterministic?
12517 These are the questions the @command{guix challenge} command attempts to
12520 The former is obviously an important question: Before using a substitute
12521 server (@pxref{Substitutes}), one had better @emph{verify} that it
12522 provides the right binaries, and thus @emph{challenge} it. The latter
12523 is what enables the former: If package builds are deterministic, then
12524 independent builds of the package should yield the exact same result,
12525 bit for bit; if a server provides a binary different from the one
12526 obtained locally, it may be either corrupt or malicious.
12528 We know that the hash that shows up in @file{/gnu/store} file names is
12529 the hash of all the inputs of the process that built the file or
12530 directory---compilers, libraries, build scripts,
12531 etc. (@pxref{Introduction}). Assuming deterministic build processes,
12532 one store file name should map to exactly one build output.
12533 @command{guix challenge} checks whether there is, indeed, a single
12534 mapping by comparing the build outputs of several independent builds of
12535 any given store item.
12537 The command output looks like this:
12540 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
12541 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
12542 updating list of substitutes from 'https://guix.example.org'... 100.0%
12543 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
12544 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
12545 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
12546 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
12548 /lib/libcrypto.so.1.1
12551 /gnu/store/@dots{}-git-2.5.0 contents differ:
12552 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
12553 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
12554 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
12556 /libexec/git-core/git-fsck
12558 /gnu/store/@dots{}-pius-2.1.1 contents differ:
12559 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
12560 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
12561 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
12563 /share/man/man1/pius.1.gz
12567 6,406 store items were analyzed:
12568 - 4,749 (74.1%) were identical
12569 - 525 (8.2%) differed
12570 - 1,132 (17.7%) were inconclusive
12574 In this example, @command{guix challenge} first scans the store to
12575 determine the set of locally-built derivations---as opposed to store
12576 items that were downloaded from a substitute server---and then queries
12577 all the substitute servers. It then reports those store items for which
12578 the servers obtained a result different from the local build.
12580 @cindex non-determinism, in package builds
12581 As an example, @code{guix.example.org} always gets a different answer.
12582 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
12583 case of Git. This might indicate that the build process of Git is
12584 non-deterministic, meaning that its output varies as a function of
12585 various things that Guix does not fully control, in spite of building
12586 packages in isolated environments (@pxref{Features}). Most common
12587 sources of non-determinism include the addition of timestamps in build
12588 results, the inclusion of random numbers, and directory listings sorted
12589 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
12592 To find out what is wrong with this Git binary, the easiest approach is
12596 guix challenge git \
12597 --diff=diffoscope \
12598 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
12601 This automatically invokes @command{diffoscope}, which displays detailed
12602 information about files that differ.
12604 Alternatively, we can do something along these lines (@pxref{Invoking guix
12608 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-git-2.5.0 \
12609 | lzip -d | guix archive -x /tmp/git
12610 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
12613 This command shows the difference between the files resulting from the
12614 local build, and the files resulting from the build on
12615 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
12616 diffutils, Comparing and Merging Files}). The @command{diff} command
12617 works great for text files. When binary files differ, a better option
12618 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
12619 visualize differences for all kinds of files.
12621 Once you have done that work, you can tell whether the differences are due
12622 to a non-deterministic build process or to a malicious server. We try
12623 hard to remove sources of non-determinism in packages to make it easier
12624 to verify substitutes, but of course, this is a process that
12625 involves not just Guix, but a large part of the free software community.
12626 In the meantime, @command{guix challenge} is one tool to help address
12629 If you are writing packages for Guix, you are encouraged to check
12630 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
12631 same build result as you did with:
12634 $ guix challenge @var{package}
12638 where @var{package} is a package specification such as
12639 @code{guile@@2.0} or @code{glibc:debug}.
12641 The general syntax is:
12644 guix challenge @var{options} [@var{packages}@dots{}]
12647 When a difference is found between the hash of a locally-built item and
12648 that of a server-provided substitute, or among substitutes provided by
12649 different servers, the command displays it as in the example above and
12650 its exit code is 2 (other non-zero exit codes denote other kinds of
12653 The one option that matters is:
12657 @item --substitute-urls=@var{urls}
12658 Consider @var{urls} the whitespace-separated list of substitute source
12659 URLs to compare to.
12661 @item --diff=@var{mode}
12662 Upon mismatches, show differences according to @var{mode}, one of:
12665 @item @code{simple} (the default)
12666 Show the list of files that differ.
12668 @item @code{diffoscope}
12669 @itemx @var{command}
12670 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
12671 two directories whose contents do not match.
12673 When @var{command} is an absolute file name, run @var{command} instead
12677 Do not show further details about the differences.
12680 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
12681 downloads the store items from the given substitute servers so that it
12686 Show details about matches (identical contents) in addition to
12687 information about mismatches.
12691 @node Invoking guix copy
12692 @section Invoking @command{guix copy}
12694 @cindex copy, of store items, over SSH
12695 @cindex SSH, copy of store items
12696 @cindex sharing store items across machines
12697 @cindex transferring store items across machines
12698 The @command{guix copy} command copies items from the store of one
12699 machine to that of another machine over a secure shell (SSH)
12700 connection@footnote{This command is available only when Guile-SSH was
12701 found. @xref{Requirements}, for details.}. For example, the following
12702 command copies the @code{coreutils} package, the user's profile, and all
12703 their dependencies over to @var{host}, logged in as @var{user}:
12706 guix copy --to=@var{user}@@@var{host} \
12707 coreutils `readlink -f ~/.guix-profile`
12710 If some of the items to be copied are already present on @var{host},
12711 they are not actually sent.
12713 The command below retrieves @code{libreoffice} and @code{gimp} from
12714 @var{host}, assuming they are available there:
12717 guix copy --from=@var{host} libreoffice gimp
12720 The SSH connection is established using the Guile-SSH client, which is
12721 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
12722 @file{~/.ssh/config}, and uses the SSH agent for authentication.
12724 The key used to sign items that are sent must be accepted by the remote
12725 machine. Likewise, the key used by the remote machine to sign items you
12726 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
12727 own daemon. @xref{Invoking guix archive}, for more information about
12728 store item authentication.
12730 The general syntax is:
12733 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
12736 You must always specify one of the following options:
12739 @item --to=@var{spec}
12740 @itemx --from=@var{spec}
12741 Specify the host to send to or receive from. @var{spec} must be an SSH
12742 spec such as @code{example.org}, @code{charlie@@example.org}, or
12743 @code{charlie@@example.org:2222}.
12746 The @var{items} can be either package names, such as @code{gimp}, or
12747 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
12749 When specifying the name of a package to send, it is first built if
12750 needed, unless @option{--dry-run} was specified. Common build options
12751 are supported (@pxref{Common Build Options}).
12754 @node Invoking guix container
12755 @section Invoking @command{guix container}
12757 @cindex @command{guix container}
12759 As of version @value{VERSION}, this tool is experimental. The interface
12760 is subject to radical change in the future.
12763 The purpose of @command{guix container} is to manipulate processes
12764 running within an isolated environment, commonly known as a
12765 ``container'', typically created by the @command{guix environment}
12766 (@pxref{Invoking guix environment}) and @command{guix system container}
12767 (@pxref{Invoking guix system}) commands.
12769 The general syntax is:
12772 guix container @var{action} @var{options}@dots{}
12775 @var{action} specifies the operation to perform with a container, and
12776 @var{options} specifies the context-specific arguments for the action.
12778 The following actions are available:
12782 Execute a command within the context of a running container.
12787 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
12790 @var{pid} specifies the process ID of the running container.
12791 @var{program} specifies an executable file name within the root file
12792 system of the container. @var{arguments} are the additional options that
12793 will be passed to @var{program}.
12795 The following command launches an interactive login shell inside a
12796 Guix system container, started by @command{guix system container}, and whose
12797 process ID is 9001:
12800 guix container exec 9001 /run/current-system/profile/bin/bash --login
12803 Note that the @var{pid} cannot be the parent process of a container. It
12804 must be PID 1 of the container or one of its child processes.
12808 @node Invoking guix weather
12809 @section Invoking @command{guix weather}
12811 Occasionally you're grumpy because substitutes are lacking and you end
12812 up building packages by yourself (@pxref{Substitutes}). The
12813 @command{guix weather} command reports on substitute availability on the
12814 specified servers so you can have an idea of whether you'll be grumpy
12815 today. It can sometimes be useful info as a user, but it is primarily
12816 useful to people running @command{guix publish} (@pxref{Invoking guix
12819 @cindex statistics, for substitutes
12820 @cindex availability of substitutes
12821 @cindex substitute availability
12822 @cindex weather, substitute availability
12823 Here's a sample run:
12826 $ guix weather --substitute-urls=https://guix.example.org
12827 computing 5,872 package derivations for x86_64-linux...
12828 looking for 6,128 store items on https://guix.example.org..
12829 updating list of substitutes from 'https://guix.example.org'... 100.0%
12830 https://guix.example.org
12831 43.4% substitutes available (2,658 out of 6,128)
12832 7,032.5 MiB of nars (compressed)
12833 19,824.2 MiB on disk (uncompressed)
12834 0.030 seconds per request (182.9 seconds in total)
12835 33.5 requests per second
12837 9.8% (342 out of 3,470) of the missing items are queued
12839 x86_64-linux: 518 (59.7%)
12840 i686-linux: 221 (25.5%)
12841 aarch64-linux: 128 (14.8%)
12842 build rate: 23.41 builds per hour
12843 x86_64-linux: 11.16 builds per hour
12844 i686-linux: 6.03 builds per hour
12845 aarch64-linux: 6.41 builds per hour
12848 @cindex continuous integration, statistics
12849 As you can see, it reports the fraction of all the packages for which
12850 substitutes are available on the server---regardless of whether
12851 substitutes are enabled, and regardless of whether this server's signing
12852 key is authorized. It also reports the size of the compressed archives
12853 (``nars'') provided by the server, the size the corresponding store
12854 items occupy in the store (assuming deduplication is turned off), and
12855 the server's throughput. The second part gives continuous integration
12856 (CI) statistics, if the server supports it. In addition, using the
12857 @option{--coverage} option, @command{guix weather} can list ``important''
12858 package substitutes missing on the server (see below).
12860 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
12861 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
12862 challenge}, it ignores signatures on those substitutes, which is
12863 innocuous since the command only gathers statistics and cannot install
12866 The general syntax is:
12869 guix weather @var{options}@dots{} [@var{packages}@dots{}]
12872 When @var{packages} is omitted, @command{guix weather} checks the availability
12873 of substitutes for @emph{all} the packages, or for those specified with
12874 @option{--manifest}; otherwise it only considers the specified packages. It
12875 is also possible to query specific system types with @option{--system}.
12876 @command{guix weather} exits with a non-zero code when the fraction of
12877 available substitutes is below 100%.
12879 The available options are listed below.
12882 @item --substitute-urls=@var{urls}
12883 @var{urls} is the space-separated list of substitute server URLs to
12884 query. When this option is omitted, the default set of substitute
12885 servers is queried.
12887 @item --system=@var{system}
12888 @itemx -s @var{system}
12889 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
12890 option can be repeated, in which case @command{guix weather} will query
12891 substitutes for several system types.
12893 @item --manifest=@var{file}
12894 Instead of querying substitutes for all the packages, only ask for those
12895 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
12896 with the @code{-m} option of @command{guix package} (@pxref{Invoking
12899 This option can be repeated several times, in which case the manifests
12902 @item --coverage[=@var{count}]
12903 @itemx -c [@var{count}]
12904 Report on substitute coverage for packages: list packages with at least
12905 @var{count} dependents (zero by default) for which substitutes are
12906 unavailable. Dependent packages themselves are not listed: if @var{b} depends
12907 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
12908 @var{b} usually lacks substitutes as well. The result looks like this:
12911 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
12912 computing 8,983 package derivations for x86_64-linux...
12913 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
12914 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
12915 @value{SUBSTITUTE-URL}
12916 64.7% substitutes available (6,047 out of 9,343)
12918 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
12919 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
12920 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
12921 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
12925 What this example shows is that @code{kcoreaddons} and presumably the 58
12926 packages that depend on it have no substitutes at
12927 @code{@value{SUBSTITUTE-SERVER}}; likewise for @code{qgpgme} and the 46
12928 packages that depend on it.
12930 If you are a Guix developer, or if you are taking care of this build farm,
12931 you'll probably want to have a closer look at these packages: they may simply
12934 @item --display-missing
12935 Display the list of store items for which substitutes are missing.
12938 @node Invoking guix processes
12939 @section Invoking @command{guix processes}
12941 The @command{guix processes} command can be useful to developers and system
12942 administrators, especially on multi-user machines and on build farms: it lists
12943 the current sessions (connections to the daemon), as well as information about
12944 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
12945 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
12946 listed.}. Here's an example of the information it returns:
12949 $ sudo guix processes
12952 ClientCommand: guix environment --ad-hoc python
12956 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
12960 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
12961 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
12962 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
12963 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
12965 ChildCommand: guix offload x86_64-linux 7200 1 28800
12967 ChildCommand: guix offload x86_64-linux 7200 1 28800
12969 ChildCommand: guix offload x86_64-linux 7200 1 28800
12972 In this example we see that @command{guix-daemon} has three clients:
12973 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
12974 integration tool; their process identifier (PID) is given by the
12975 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
12976 @command{guix-daemon} sub-process of this particular session.
12978 The @code{LockHeld} fields show which store items are currently locked
12979 by this session, which corresponds to store items being built or
12980 substituted (the @code{LockHeld} field is not displayed when
12981 @command{guix processes} is not running as root). Last, by looking at
12982 the @code{ChildPID} and @code{ChildCommand} fields, we understand that
12983 these three builds are being offloaded (@pxref{Daemon Offload Setup}).
12985 The output is in Recutils format so we can use the handy @command{recsel}
12986 command to select sessions of interest (@pxref{Selection Expressions,,,
12987 recutils, GNU recutils manual}). As an example, the command shows the command
12988 line and PID of the client that triggered the build of a Perl package:
12991 $ sudo guix processes | \
12992 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
12994 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
12997 Additional options are listed below.
13000 @item --format=@var{format}
13001 @itemx -f @var{format}
13002 Produce output in the specified @var{format}, one of:
13006 The default option. It outputs a set of Session recutils records
13007 that include each @code{ChildProcess} as a field.
13010 Normalize the output records into record sets (@pxref{Record Sets,,,
13011 recutils, GNU recutils manual}). Normalizing into record sets allows
13012 joins across record types. The example below lists the PID of each
13013 @code{ChildProcess} and the associated PID for @code{Session} that
13014 spawned the @code{ChildProcess} where the @code{Session} was started
13015 using @command{guix build}.
13018 $ guix processes --format=normalized | \
13022 -p Session.PID,PID \
13023 -e 'Session.ClientCommand ~ "guix build"'
13036 @node System Configuration
13037 @chapter System Configuration
13039 @cindex system configuration
13040 Guix System supports a consistent whole-system configuration
13041 mechanism. By that we mean that all aspects of the global system
13042 configuration---such as the available system services, timezone and
13043 locale settings, user accounts---are declared in a single place. Such
13044 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
13046 One of the advantages of putting all the system configuration under the
13047 control of Guix is that it supports transactional system upgrades, and
13048 makes it possible to roll back to a previous system instantiation,
13049 should something go wrong with the new one (@pxref{Features}). Another
13050 advantage is that it makes it easy to replicate the exact same configuration
13051 across different machines, or at different points in time, without
13052 having to resort to additional administration tools layered on top of
13053 the own tools of the system.
13054 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
13056 This section describes this mechanism. First we focus on the system
13057 administrator's viewpoint---explaining how the system is configured and
13058 instantiated. Then we show how this mechanism can be extended, for
13059 instance to support new system services.
13062 * Using the Configuration System:: Customizing your GNU system.
13063 * operating-system Reference:: Detail of operating-system declarations.
13064 * File Systems:: Configuring file system mounts.
13065 * Mapped Devices:: Block device extra processing.
13066 * User Accounts:: Specifying user accounts.
13067 * Keyboard Layout:: How the system interprets key strokes.
13068 * Locales:: Language and cultural convention settings.
13069 * Services:: Specifying system services.
13070 * Setuid Programs:: Programs running with root privileges.
13071 * X.509 Certificates:: Authenticating HTTPS servers.
13072 * Name Service Switch:: Configuring libc's name service switch.
13073 * Initial RAM Disk:: Linux-Libre bootstrapping.
13074 * Bootloader Configuration:: Configuring the boot loader.
13075 * Invoking guix system:: Instantiating a system configuration.
13076 * Invoking guix deploy:: Deploying a system configuration to a remote host.
13077 * Running Guix in a VM:: How to run Guix System in a virtual machine.
13078 * Defining Services:: Adding new service definitions.
13081 @node Using the Configuration System
13082 @section Using the Configuration System
13084 The operating system is configured by providing an
13085 @code{operating-system} declaration in a file that can then be passed to
13086 the @command{guix system} command (@pxref{Invoking guix system}). A
13087 simple setup, with the default system services, the default Linux-Libre
13088 kernel, initial RAM disk, and boot loader looks like this:
13090 @findex operating-system
13092 @include os-config-bare-bones.texi
13095 This example should be self-describing. Some of the fields defined
13096 above, such as @code{host-name} and @code{bootloader}, are mandatory.
13097 Others, such as @code{packages} and @code{services}, can be omitted, in
13098 which case they get a default value.
13100 Below we discuss the effect of some of the most important fields
13101 (@pxref{operating-system Reference}, for details about all the available
13102 fields), and how to @dfn{instantiate} the operating system using
13103 @command{guix system}.
13105 @unnumberedsubsec Bootloader
13107 @cindex legacy boot, on Intel machines
13108 @cindex BIOS boot, on Intel machines
13111 The @code{bootloader} field describes the method that will be used to boot
13112 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
13113 mode, as in the example above. However, more recent machines rely instead on
13114 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
13115 the @code{bootloader} field should contain something along these lines:
13118 (bootloader-configuration
13119 (bootloader grub-efi-bootloader)
13120 (target "/boot/efi"))
13123 @xref{Bootloader Configuration}, for more information on the available
13124 configuration options.
13126 @unnumberedsubsec Globally-Visible Packages
13128 @vindex %base-packages
13129 The @code{packages} field lists packages that will be globally visible
13130 on the system, for all user accounts---i.e., in every user's @env{PATH}
13131 environment variable---in addition to the per-user profiles
13132 (@pxref{Invoking guix package}). The @code{%base-packages} variable
13133 provides all the tools one would expect for basic user and administrator
13134 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
13135 the GNU Zile lightweight text editor, @command{find}, @command{grep},
13136 etc. The example above adds GNU@tie{}Screen to those,
13137 taken from the @code{(gnu packages screen)}
13138 module (@pxref{Package Modules}). The
13139 @code{(list package output)} syntax can be used to add a specific output
13143 (use-modules (gnu packages))
13144 (use-modules (gnu packages dns))
13148 (packages (cons (list bind "utils")
13152 @findex specification->package
13153 Referring to packages by variable name, like @code{bind} above, has
13154 the advantage of being unambiguous; it also allows typos and such to be
13155 diagnosed right away as ``unbound variables''. The downside is that one
13156 needs to know which module defines which package, and to augment the
13157 @code{use-package-modules} line accordingly. To avoid that, one can use
13158 the @code{specification->package} procedure of the @code{(gnu packages)}
13159 module, which returns the best package for a given name or name and
13163 (use-modules (gnu packages))
13167 (packages (append (map specification->package
13168 '("tcpdump" "htop" "gnupg@@2.0"))
13172 @unnumberedsubsec System Services
13175 @vindex %base-services
13176 The @code{services} field lists @dfn{system services} to be made
13177 available when the system starts (@pxref{Services}).
13178 The @code{operating-system} declaration above specifies that, in
13179 addition to the basic services, we want the OpenSSH secure shell
13180 daemon listening on port 2222 (@pxref{Networking Services,
13181 @code{openssh-service-type}}). Under the hood,
13182 @code{openssh-service-type} arranges so that @command{sshd} is started with the
13183 right command-line options, possibly with supporting configuration files
13184 generated as needed (@pxref{Defining Services}).
13186 @cindex customization, of services
13187 @findex modify-services
13188 Occasionally, instead of using the base services as is, you will want to
13189 customize them. To do this, use @code{modify-services} (@pxref{Service
13190 Reference, @code{modify-services}}) to modify the list.
13192 For example, suppose you want to modify @code{guix-daemon} and Mingetty
13193 (the console log-in) in the @code{%base-services} list (@pxref{Base
13194 Services, @code{%base-services}}). To do that, you can write the
13195 following in your operating system declaration:
13198 (define %my-services
13199 ;; My very own list of services.
13200 (modify-services %base-services
13201 (guix-service-type config =>
13202 (guix-configuration
13204 ;; Fetch substitutes from example.org.
13206 (list "https://example.org/guix"
13207 "https://ci.guix.gnu.org"))))
13208 (mingetty-service-type config =>
13209 (mingetty-configuration
13211 ;; Automatially log in as "guest".
13212 (auto-login "guest")))))
13216 (services %my-services))
13219 This changes the configuration---i.e., the service parameters---of the
13220 @code{guix-service-type} instance, and that of all the
13221 @code{mingetty-service-type} instances in the @code{%base-services} list.
13222 Observe how this is accomplished: first, we arrange for the original
13223 configuration to be bound to the identifier @code{config} in the
13224 @var{body}, and then we write the @var{body} so that it evaluates to the
13225 desired configuration. In particular, notice how we use @code{inherit}
13226 to create a new configuration which has the same values as the old
13227 configuration, but with a few modifications.
13229 @cindex encrypted disk
13230 The configuration for a typical ``desktop'' usage, with an encrypted
13231 root partition, the X11 display
13232 server, GNOME and Xfce (users can choose which of these desktop
13233 environments to use at the log-in screen by pressing @kbd{F1}), network
13234 management, power management, and more, would look like this:
13237 @include os-config-desktop.texi
13240 A graphical system with a choice of lightweight window managers
13241 instead of full-blown desktop environments would look like this:
13244 @include os-config-lightweight-desktop.texi
13247 This example refers to the @file{/boot/efi} file system by its UUID,
13248 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
13249 as returned by the @command{blkid} command.
13251 @xref{Desktop Services}, for the exact list of services provided by
13252 @code{%desktop-services}. @xref{X.509 Certificates}, for background
13253 information about the @code{nss-certs} package that is used here.
13255 Again, @code{%desktop-services} is just a list of service objects. If
13256 you want to remove services from there, you can do so using the
13257 procedures for list filtering (@pxref{SRFI-1 Filtering and
13258 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
13259 following expression returns a list that contains all the services in
13260 @code{%desktop-services} minus the Avahi service:
13263 (remove (lambda (service)
13264 (eq? (service-kind service) avahi-service-type))
13268 @unnumberedsubsec Instantiating the System
13270 Assuming the @code{operating-system} declaration
13271 is stored in the @file{my-system-config.scm}
13272 file, the @command{guix system reconfigure my-system-config.scm} command
13273 instantiates that configuration, and makes it the default GRUB boot
13274 entry (@pxref{Invoking guix system}).
13276 The normal way to change the system configuration is by updating this
13277 file and re-running @command{guix system reconfigure}. One should never
13278 have to touch files in @file{/etc} or to run commands that modify the
13279 system state such as @command{useradd} or @command{grub-install}. In
13280 fact, you must avoid that since that would not only void your warranty
13281 but also prevent you from rolling back to previous versions of your
13282 system, should you ever need to.
13284 @cindex roll-back, of the operating system
13285 Speaking of roll-back, each time you run @command{guix system
13286 reconfigure}, a new @dfn{generation} of the system is created---without
13287 modifying or deleting previous generations. Old system generations get
13288 an entry in the bootloader boot menu, allowing you to boot them in case
13289 something went wrong with the latest generation. Reassuring, no? The
13290 @command{guix system list-generations} command lists the system
13291 generations available on disk. It is also possible to roll back the
13292 system via the commands @command{guix system roll-back} and
13293 @command{guix system switch-generation}.
13295 Although the @command{guix system reconfigure} command will not modify
13296 previous generations, you must take care when the current generation is not
13297 the latest (e.g., after invoking @command{guix system roll-back}), since
13298 the operation might overwrite a later generation (@pxref{Invoking guix
13301 @unnumberedsubsec The Programming Interface
13303 At the Scheme level, the bulk of an @code{operating-system} declaration
13304 is instantiated with the following monadic procedure (@pxref{The Store
13307 @deffn {Monadic Procedure} operating-system-derivation os
13308 Return a derivation that builds @var{os}, an @code{operating-system}
13309 object (@pxref{Derivations}).
13311 The output of the derivation is a single directory that refers to all
13312 the packages, configuration files, and other supporting files needed to
13313 instantiate @var{os}.
13316 This procedure is provided by the @code{(gnu system)} module. Along
13317 with @code{(gnu services)} (@pxref{Services}), this module contains the
13318 guts of Guix System. Make sure to visit it!
13321 @node operating-system Reference
13322 @section @code{operating-system} Reference
13324 This section summarizes all the options available in
13325 @code{operating-system} declarations (@pxref{Using the Configuration
13328 @deftp {Data Type} operating-system
13329 This is the data type representing an operating system configuration.
13330 By that, we mean all the global system configuration, not per-user
13331 configuration (@pxref{Using the Configuration System}).
13334 @item @code{kernel} (default: @code{linux-libre})
13335 The package object of the operating system kernel to
13336 use@footnote{Currently only the Linux-libre kernel is fully supported.
13337 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
13338 available when building a virtual machine disk image.}.
13341 @item @code{hurd} (default: @code{#f})
13342 The package object of the Hurd to be started by the kernel. When this
13343 field is set, produce a GNU/Hurd operating system. In that case,
13344 @code{kernel} must also be set to the @code{gnumach} package---the
13345 microkernel the Hurd runs on.
13348 This feature is experimental and only supported for disk images.
13351 @item @code{kernel-loadable-modules} (default: '())
13352 A list of objects (usually packages) to collect loadable kernel modules
13353 from--e.g. @code{(list ddcci-driver-linux)}.
13355 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
13356 List of strings or gexps representing additional arguments to pass on
13357 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
13359 @item @code{bootloader}
13360 The system bootloader configuration object. @xref{Bootloader Configuration}.
13363 This is the label (a string) as it appears in the bootloader's menu entry.
13364 The default label includes the kernel name and version.
13366 @item @code{keyboard-layout} (default: @code{#f})
13367 This field specifies the keyboard layout to use in the console. It can be
13368 either @code{#f}, in which case the default keyboard layout is used (usually
13369 US English), or a @code{<keyboard-layout>} record. @xref{Keyboard Layout},
13370 for more information.
13372 This keyboard layout is in effect as soon as the kernel has booted. For
13373 instance, it is the keyboard layout in effect when you type a passphrase if
13374 your root file system is on a @code{luks-device-mapping} mapped device
13375 (@pxref{Mapped Devices}).
13378 This does @emph{not} specify the keyboard layout used by the bootloader, nor
13379 that used by the graphical display server. @xref{Bootloader Configuration},
13380 for information on how to specify the bootloader's keyboard layout. @xref{X
13381 Window}, for information on how to specify the keyboard layout used by the X
13385 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
13387 @cindex initial RAM disk
13388 The list of Linux kernel modules that need to be available in the
13389 initial RAM disk. @xref{Initial RAM Disk}.
13391 @item @code{initrd} (default: @code{base-initrd})
13392 A procedure that returns an initial RAM disk for the Linux
13393 kernel. This field is provided to support low-level customization and
13394 should rarely be needed for casual use. @xref{Initial RAM Disk}.
13396 @item @code{firmware} (default: @code{%base-firmware})
13398 List of firmware packages loadable by the operating system kernel.
13400 The default includes firmware needed for Atheros- and Broadcom-based
13401 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
13402 respectively). @xref{Hardware Considerations}, for more info on
13403 supported hardware.
13405 @item @code{host-name}
13408 @item @code{hosts-file}
13410 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
13411 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
13412 Reference Manual}). The default is a file with entries for
13413 @code{localhost} and @var{host-name}.
13415 @item @code{mapped-devices} (default: @code{'()})
13416 A list of mapped devices. @xref{Mapped Devices}.
13418 @item @code{file-systems}
13419 A list of file systems. @xref{File Systems}.
13421 @cindex swap devices
13423 @item @code{swap-devices} (default: @code{'()})
13424 A list of UUIDs, file system labels, or strings identifying devices or
13425 files to be used for ``swap
13426 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
13427 Manual}). Here are some examples:
13430 @item (list (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb"))
13431 Use the swap partition with the given UUID. You can learn the UUID of a
13432 Linux swap partition by running @command{swaplabel @var{device}}, where
13433 @var{device} is the @file{/dev} file name of that partition.
13435 @item (list (file-system-label "swap"))
13436 Use the partition with label @code{swap}. Again, the
13437 @command{swaplabel} command allows you to view and change the label of a
13438 Linux swap partition.
13440 @item (list "/swapfile")
13441 Use the file @file{/swapfile} as swap space.
13443 @item (list "/dev/sda3" "/dev/sdb2")
13444 Use the @file{/dev/sda3} and @file{/dev/sdb2} partitions as swap space.
13445 We recommend referring to swap devices by UUIDs or labels as shown above
13449 It is possible to specify a swap file in a file system on a mapped
13450 device (under @file{/dev/mapper}), provided that the necessary device
13451 mapping and file system are also specified. @xref{Mapped Devices} and
13452 @ref{File Systems}.
13454 @item @code{users} (default: @code{%base-user-accounts})
13455 @itemx @code{groups} (default: @code{%base-groups})
13456 List of user accounts and groups. @xref{User Accounts}.
13458 If the @code{users} list lacks a user account with UID@tie{}0, a
13459 ``root'' account with UID@tie{}0 is automatically added.
13461 @item @code{skeletons} (default: @code{(default-skeletons)})
13462 A list of target file name/file-like object tuples (@pxref{G-Expressions,
13463 file-like objects}). These are the skeleton files that will be added to
13464 the home directory of newly-created user accounts.
13466 For instance, a valid value may look like this:
13469 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
13470 (".guile" ,(plain-file "guile"
13471 "(use-modules (ice-9 readline))
13472 (activate-readline)")))
13475 @item @code{issue} (default: @code{%default-issue})
13476 A string denoting the contents of the @file{/etc/issue} file, which is
13477 displayed when users log in on a text console.
13479 @item @code{packages} (default: @code{%base-packages})
13480 A list of packages to be installed in the global profile, which is accessible
13481 at @file{/run/current-system/profile}. Each element is either a package
13482 variable or a package/output tuple. Here's a simple example of both:
13485 (cons* git ; the default "out" output
13486 (list git "send-email") ; another output of git
13487 %base-packages) ; the default set
13490 The default set includes core utilities and it is good practice to
13491 install non-core utilities in user profiles (@pxref{Invoking guix
13494 @item @code{timezone}
13495 A timezone identifying string---e.g., @code{"Europe/Paris"}.
13497 You can run the @command{tzselect} command to find out which timezone
13498 string corresponds to your region. Choosing an invalid timezone name
13499 causes @command{guix system} to fail.
13501 @item @code{locale} (default: @code{"en_US.utf8"})
13502 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
13503 Library Reference Manual}). @xref{Locales}, for more information.
13505 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
13506 The list of locale definitions to be compiled and that may be used at
13507 run time. @xref{Locales}.
13509 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
13510 The list of GNU@tie{}libc packages whose locale data and tools are used
13511 to build the locale definitions. @xref{Locales}, for compatibility
13512 considerations that justify this option.
13514 @item @code{name-service-switch} (default: @code{%default-nss})
13515 Configuration of the libc name service switch (NSS)---a
13516 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
13519 @item @code{services} (default: @code{%base-services})
13520 A list of service objects denoting system services. @xref{Services}.
13522 @cindex essential services
13523 @item @code{essential-services} (default: ...)
13524 The list of ``essential services''---i.e., things like instances of
13525 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
13526 Reference}), which are derived from the operating system definition itself.
13527 As a user you should @emph{never} need to touch this field.
13529 @item @code{pam-services} (default: @code{(base-pam-services)})
13531 @cindex pluggable authentication modules
13532 Linux @dfn{pluggable authentication module} (PAM) services.
13533 @c FIXME: Add xref to PAM services section.
13535 @item @code{setuid-programs} (default: @code{%setuid-programs})
13536 List of string-valued G-expressions denoting setuid programs.
13537 @xref{Setuid Programs}.
13539 @item @code{sudoers-file} (default: @code{%sudoers-specification})
13540 @cindex sudoers file
13541 The contents of the @file{/etc/sudoers} file as a file-like object
13542 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
13544 This file specifies which users can use the @command{sudo} command, what
13545 they are allowed to do, and what privileges they may gain. The default
13546 is that only @code{root} and members of the @code{wheel} group may use
13551 @deffn {Scheme Syntax} this-operating-system
13552 When used in the @emph{lexical scope} of an operating system field definition,
13553 this identifier resolves to the operating system being defined.
13555 The example below shows how to refer to the operating system being defined in
13556 the definition of the @code{label} field:
13559 (use-modules (gnu) (guix))
13563 (label (package-full-name
13564 (operating-system-kernel this-operating-system))))
13567 It is an error to refer to @code{this-operating-system} outside an operating
13574 @section File Systems
13576 The list of file systems to be mounted is specified in the
13577 @code{file-systems} field of the operating system declaration
13578 (@pxref{Using the Configuration System}). Each file system is declared
13579 using the @code{file-system} form, like this:
13583 (mount-point "/home")
13584 (device "/dev/sda3")
13588 As usual, some of the fields are mandatory---those shown in the example
13589 above---while others can be omitted. These are described below.
13591 @deftp {Data Type} file-system
13592 Objects of this type represent file systems to be mounted. They
13593 contain the following members:
13597 This is a string specifying the type of the file system---e.g.,
13600 @item @code{mount-point}
13601 This designates the place where the file system is to be mounted.
13603 @item @code{device}
13604 This names the ``source'' of the file system. It can be one of three
13605 things: a file system label, a file system UUID, or the name of a
13606 @file{/dev} node. Labels and UUIDs offer a way to refer to file
13607 systems without having to hard-code their actual device
13608 name@footnote{Note that, while it is tempting to use
13609 @file{/dev/disk/by-uuid} and similar device names to achieve the same
13610 result, this is not recommended: These special device nodes are created
13611 by the udev daemon and may be unavailable at the time the device is
13614 @findex file-system-label
13615 File system labels are created using the @code{file-system-label}
13616 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
13617 plain strings. Here's an example of a file system referred to by its
13618 label, as shown by the @command{e2label} command:
13622 (mount-point "/home")
13624 (device (file-system-label "my-home")))
13628 UUIDs are converted from their string representation (as shown by the
13629 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
13630 @code{uuid} form expects 16-byte UUIDs as defined in
13631 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
13632 form of UUID used by the ext2 family of file systems and others, but it
13633 is different from ``UUIDs'' found in FAT file systems, for instance.},
13638 (mount-point "/home")
13640 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
13643 When the source of a file system is a mapped device (@pxref{Mapped
13644 Devices}), its @code{device} field @emph{must} refer to the mapped
13645 device name---e.g., @file{"/dev/mapper/root-partition"}.
13646 This is required so that
13647 the system knows that mounting the file system depends on having the
13648 corresponding device mapping established.
13650 @item @code{flags} (default: @code{'()})
13651 This is a list of symbols denoting mount flags. Recognized flags
13652 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
13653 access to special files), @code{no-suid} (ignore setuid and setgid
13654 bits), @code{no-atime} (do not update file access times),
13655 @code{strict-atime} (update file access time), @code{lazy-time} (only
13656 update time on the in-memory version of the file inode), and
13657 @code{no-exec} (disallow program execution).
13658 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
13659 Manual}, for more information on these flags.
13661 @item @code{options} (default: @code{#f})
13662 This is either @code{#f}, or a string denoting mount options passed to
13663 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
13664 Library Reference Manual}, for details and run @command{man 8 mount} for
13665 options for various file systems. Note that the
13666 @code{file-system-options->alist} and @code{alist->file-system-options}
13667 procedures from @code{(gnu system file-systems)} can be used to convert
13668 file system options given as an association list to the string
13669 representation, and vice-versa.
13671 @item @code{mount?} (default: @code{#t})
13672 This value indicates whether to automatically mount the file system when
13673 the system is brought up. When set to @code{#f}, the file system gets
13674 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
13675 is not automatically mounted.
13677 @item @code{needed-for-boot?} (default: @code{#f})
13678 This Boolean value indicates whether the file system is needed when
13679 booting. If that is true, then the file system is mounted when the
13680 initial RAM disk (initrd) is loaded. This is always the case, for
13681 instance, for the root file system.
13683 @item @code{check?} (default: @code{#t})
13684 This Boolean indicates whether the file system needs to be checked for
13685 errors before being mounted.
13687 @item @code{create-mount-point?} (default: @code{#f})
13688 When true, the mount point is created if it does not exist yet.
13690 @item @code{mount-may-fail?} (default: @code{#f})
13691 When true, this indicates that mounting this file system can fail but
13692 that should not be considered an error. This is useful in unusual
13693 cases; an example of this is @code{efivarfs}, a file system that can
13694 only be mounted on EFI/UEFI systems.
13696 @item @code{dependencies} (default: @code{'()})
13697 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
13698 representing file systems that must be mounted or mapped devices that
13699 must be opened before (and unmounted or closed after) this one.
13701 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
13702 a dependency of @file{/sys/fs/cgroup/cpu} and
13703 @file{/sys/fs/cgroup/memory}.
13705 Another example is a file system that depends on a mapped device, for
13706 example for an encrypted partition (@pxref{Mapped Devices}).
13710 @deffn {Scheme Procedure} file-system-label @var{str}
13711 This procedure returns an opaque file system label from @var{str}, a
13715 (file-system-label "home")
13716 @result{} #<file-system-label "home">
13719 File system labels are used to refer to file systems by label rather
13720 than by device name. See above for examples.
13723 The @code{(gnu system file-systems)} exports the following useful
13726 @defvr {Scheme Variable} %base-file-systems
13727 These are essential file systems that are required on normal systems,
13728 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
13729 below). Operating system declarations should always contain at least
13733 @defvr {Scheme Variable} %pseudo-terminal-file-system
13734 This is the file system to be mounted as @file{/dev/pts}. It supports
13735 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
13736 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
13737 Manual}). Pseudo-terminals are used by terminal emulators such as
13741 @defvr {Scheme Variable} %shared-memory-file-system
13742 This file system is mounted as @file{/dev/shm} and is used to support
13743 memory sharing across processes (@pxref{Memory-mapped I/O,
13744 @code{shm_open},, libc, The GNU C Library Reference Manual}).
13747 @defvr {Scheme Variable} %immutable-store
13748 This file system performs a read-only ``bind mount'' of
13749 @file{/gnu/store}, making it read-only for all the users including
13750 @code{root}. This prevents against accidental modification by software
13751 running as @code{root} or by system administrators.
13753 The daemon itself is still able to write to the store: it remounts it
13754 read-write in its own ``name space.''
13757 @defvr {Scheme Variable} %binary-format-file-system
13758 The @code{binfmt_misc} file system, which allows handling of arbitrary
13759 executable file types to be delegated to user space. This requires the
13760 @code{binfmt.ko} kernel module to be loaded.
13763 @defvr {Scheme Variable} %fuse-control-file-system
13764 The @code{fusectl} file system, which allows unprivileged users to mount
13765 and unmount user-space FUSE file systems. This requires the
13766 @code{fuse.ko} kernel module to be loaded.
13769 The @code{(gnu system uuid)} module provides tools to deal with file
13770 system ``unique identifiers'' (UUIDs).
13772 @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
13773 Return an opaque UUID (unique identifier) object of the given @var{type}
13774 (a symbol) by parsing @var{str} (a string):
13777 (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
13778 @result{} #<<uuid> type: dce bv: @dots{}>
13780 (uuid "1234-ABCD" 'fat)
13781 @result{} #<<uuid> type: fat bv: @dots{}>
13784 @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
13785 @code{ntfs}, or one of the commonly found synonyms for these.
13787 UUIDs are another way to unambiguously refer to file systems in
13788 operating system configuration. See the examples above.
13792 @node Btrfs file system
13793 @subsection Btrfs file system
13795 The Btrfs has special features, such as subvolumes, that merit being
13796 explained in more details. The following section attempts to cover
13797 basic as well as complex uses of a Btrfs file system with the Guix
13800 In its simplest usage, a Btrfs file system can be described, for
13805 (mount-point "/home")
13807 (device (file-system-label "my-home")))
13810 The example below is more complex, as it makes use of a Btrfs
13811 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
13812 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
13813 dependency on @code{mapped-devices}):
13817 (device (file-system-label "my-btrfs-pool"))
13820 (options "subvol=rootfs")
13821 (dependencies mapped-devices))
13824 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
13825 top level during the early boot, and rely on their configuration to
13826 refer to the correct subvolume path within that top level. The
13827 bootloaders operating in this way typically produce their configuration
13828 on a running system where the Btrfs partitions are already mounted and
13829 where the subvolume information is readily available. As an example,
13830 @command{grub-mkconfig}, the configuration generator command shipped
13831 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
13832 path of a subvolume.
13834 The Guix System produces a bootloader configuration using the operating
13835 system configuration as its sole input; it is therefore necessary to
13836 extract the subvolume name on which @file{/gnu/store} lives (if any)
13837 from that operating system configuration. To better illustrate,
13838 consider a subvolume named 'rootfs' which contains the root file system
13839 data. In such situation, the GRUB bootloader would only see the top
13840 level of the root Btrfs partition, e.g.:
13844 ├── rootfs (subvolume directory)
13845 ├── gnu (normal directory)
13846 ├── store (normal directory)
13850 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
13851 of the kernel, initrd binaries and any other files referred to in the
13852 GRUB configuration that must be found during the early boot.
13854 The next example shows a nested hierarchy of subvolumes and
13859 ├── rootfs (subvolume)
13860 ├── gnu (normal directory)
13861 ├── store (subvolume)
13865 This scenario would work without mounting the 'store' subvolume.
13866 Mounting 'rootfs' is sufficient, since the subvolume name matches its
13867 intended mount point in the file system hierarchy. Alternatively, the
13868 'store' subvolume could be referred to by setting the @code{subvol}
13869 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
13871 Finally, a more contrived example of nested subvolumes:
13875 ├── root-snapshots (subvolume)
13876 ├── root-current (subvolume)
13877 ├── guix-store (subvolume)
13881 Here, the 'guix-store' subvolume doesn't match its intended mount point,
13882 so it is necessary to mount it. The subvolume must be fully specified,
13883 by passing its file name to the @code{subvol} option. To illustrate,
13884 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
13885 a file system declaration such as:
13889 (device (file-system-label "btrfs-pool-1"))
13890 (mount-point "/gnu/store")
13892 (options "subvol=root-snapshots/root-current/guix-store,\
13893 compress-force=zstd,space_cache=v2"))
13896 @node Mapped Devices
13897 @section Mapped Devices
13899 @cindex device mapping
13900 @cindex mapped devices
13901 The Linux kernel has a notion of @dfn{device mapping}: a block device,
13902 such as a hard disk partition, can be @dfn{mapped} into another device,
13903 usually in @code{/dev/mapper/},
13904 with additional processing over the data that flows through
13905 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
13906 concept of a ``mapped device'' and that of a file system: both boil down
13907 to @emph{translating} input/output operations made on a file to
13908 operations on its backing store. Thus, the Hurd implements mapped
13909 devices, like file systems, using the generic @dfn{translator} mechanism
13910 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
13911 typical example is encryption device mapping: all writes to the mapped
13912 device are encrypted, and all reads are deciphered, transparently.
13913 Guix extends this notion by considering any device or set of devices that
13914 are @dfn{transformed} in some way to create a new device; for instance,
13915 RAID devices are obtained by @dfn{assembling} several other devices, such
13916 as hard disks or partitions, into a new one that behaves as one partition.
13918 Mapped devices are declared using the @code{mapped-device} form,
13919 defined as follows; for examples, see below.
13921 @deftp {Data Type} mapped-device
13922 Objects of this type represent device mappings that will be made when
13923 the system boots up.
13927 This is either a string specifying the name of the block device to be mapped,
13928 such as @code{"/dev/sda3"}, or a list of such strings when several devices
13929 need to be assembled for creating a new one. In case of LVM this is a
13930 string specifying name of the volume group to be mapped.
13933 This string specifies the name of the resulting mapped device. For
13934 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
13935 specifying @code{"my-partition"} leads to the creation of
13936 the @code{"/dev/mapper/my-partition"} device.
13937 For RAID devices of type @code{raid-device-mapping}, the full device name
13938 such as @code{"/dev/md0"} needs to be given.
13939 LVM logical volumes of type @code{lvm-device-mapping} need to
13940 be specified as @code{"VGNAME-LVNAME"}.
13943 This list of strings specifies names of the resulting mapped devices in case
13944 there are several. The format is identical to @var{target}.
13947 This must be a @code{mapped-device-kind} object, which specifies how
13948 @var{source} is mapped to @var{target}.
13952 @defvr {Scheme Variable} luks-device-mapping
13953 This defines LUKS block device encryption using the @command{cryptsetup}
13954 command from the package with the same name. It relies on the
13955 @code{dm-crypt} Linux kernel module.
13958 @defvr {Scheme Variable} raid-device-mapping
13959 This defines a RAID device, which is assembled using the @code{mdadm}
13960 command from the package with the same name. It requires a Linux kernel
13961 module for the appropriate RAID level to be loaded, such as @code{raid456}
13962 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
13965 @cindex LVM, logical volume manager
13966 @defvr {Scheme Variable} lvm-device-mapping
13967 This defines one or more logical volumes for the Linux
13968 @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
13969 The volume group is activated by the @command{vgchange} command from the
13970 @code{lvm2} package.
13973 @cindex disk encryption
13975 The following example specifies a mapping from @file{/dev/sda3} to
13976 @file{/dev/mapper/home} using LUKS---the
13977 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
13978 standard mechanism for disk encryption.
13979 The @file{/dev/mapper/home}
13980 device can then be used as the @code{device} of a @code{file-system}
13981 declaration (@pxref{File Systems}).
13985 (source "/dev/sda3")
13987 (type luks-device-mapping))
13990 Alternatively, to become independent of device numbering, one may obtain
13991 the LUKS UUID (@dfn{unique identifier}) of the source device by a
13995 cryptsetup luksUUID /dev/sda3
13998 and use it as follows:
14002 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
14004 (type luks-device-mapping))
14007 @cindex swap encryption
14008 It is also desirable to encrypt swap space, since swap space may contain
14009 sensitive data. One way to accomplish that is to use a swap file in a
14010 file system on a device mapped via LUKS encryption. In this way, the
14011 swap file is encrypted because the entire device is encrypted.
14012 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
14014 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
14015 may be declared as follows:
14019 (source (list "/dev/sda1" "/dev/sdb1"))
14020 (target "/dev/md0")
14021 (type raid-device-mapping))
14024 The @file{/dev/md0} device can then be used as the @code{device} of a
14025 @code{file-system} declaration (@pxref{File Systems}).
14026 Note that the RAID level need not be given; it is chosen during the
14027 initial creation and formatting of the RAID device and is determined
14028 automatically later.
14030 LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
14031 be declared as follows:
14036 (target (list "vg0-alpha" "vg0-beta"))
14037 (type lvm-device-mapping))
14040 Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
14041 then be used as the @code{device} of a @code{file-system} declaration
14042 (@pxref{File Systems}).
14044 @node User Accounts
14045 @section User Accounts
14049 @cindex user accounts
14050 User accounts and groups are entirely managed through the
14051 @code{operating-system} declaration. They are specified with the
14052 @code{user-account} and @code{user-group} forms:
14058 (supplementary-groups '("wheel" ;allow use of sudo, etc.
14059 "audio" ;sound card
14060 "video" ;video devices such as webcams
14061 "cdrom")) ;the good ol' CD-ROM
14062 (comment "Bob's sister"))
14065 Here's a user account that uses a different shell and a custom home
14066 directory (the default would be @file{"/home/bob"}):
14072 (comment "Alice's bro")
14073 (shell (file-append zsh "/bin/zsh"))
14074 (home-directory "/home/robert"))
14077 When booting or upon completion of @command{guix system reconfigure},
14078 the system ensures that only the user accounts and groups specified in
14079 the @code{operating-system} declaration exist, and with the specified
14080 properties. Thus, account or group creations or modifications made by
14081 directly invoking commands such as @command{useradd} are lost upon
14082 reconfiguration or reboot. This ensures that the system remains exactly
14085 @deftp {Data Type} user-account
14086 Objects of this type represent user accounts. The following members may
14091 The name of the user account.
14095 This is the name (a string) or identifier (a number) of the user group
14096 this account belongs to.
14098 @item @code{supplementary-groups} (default: @code{'()})
14099 Optionally, this can be defined as a list of group names that this
14100 account belongs to.
14102 @item @code{uid} (default: @code{#f})
14103 This is the user ID for this account (a number), or @code{#f}. In the
14104 latter case, a number is automatically chosen by the system when the
14105 account is created.
14107 @item @code{comment} (default: @code{""})
14108 A comment about the account, such as the account owner's full name.
14110 @item @code{home-directory}
14111 This is the name of the home directory for the account.
14113 @item @code{create-home-directory?} (default: @code{#t})
14114 Indicates whether the home directory of this account should be created
14115 if it does not exist yet.
14117 @item @code{shell} (default: Bash)
14118 This is a G-expression denoting the file name of a program to be used as
14119 the shell (@pxref{G-Expressions}). For example, you would refer to the
14120 Bash executable like this:
14123 (file-append bash "/bin/bash")
14127 ... and to the Zsh executable like that:
14130 (file-append zsh "/bin/zsh")
14133 @item @code{system?} (default: @code{#f})
14134 This Boolean value indicates whether the account is a ``system''
14135 account. System accounts are sometimes treated specially; for instance,
14136 graphical login managers do not list them.
14138 @anchor{user-account-password}
14139 @cindex password, for user accounts
14140 @item @code{password} (default: @code{#f})
14141 You would normally leave this field to @code{#f}, initialize user
14142 passwords as @code{root} with the @command{passwd} command, and then let
14143 users change it with @command{passwd}. Passwords set with
14144 @command{passwd} are of course preserved across reboot and
14147 If you @emph{do} want to set an initial password for an account, then
14148 this field must contain the encrypted password, as a string. You can use the
14149 @code{crypt} procedure for this purpose:
14156 ;; Specify a SHA-512-hashed initial password.
14157 (password (crypt "InitialPassword!" "$6$abc")))
14161 The hash of this initial password will be available in a file in
14162 @file{/gnu/store}, readable by all the users, so this method must be used with
14166 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
14167 more information on password encryption, and @ref{Encryption,,, guile, GNU
14168 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
14174 User group declarations are even simpler:
14177 (user-group (name "students"))
14180 @deftp {Data Type} user-group
14181 This type is for, well, user groups. There are just a few fields:
14185 The name of the group.
14187 @item @code{id} (default: @code{#f})
14188 The group identifier (a number). If @code{#f}, a new number is
14189 automatically allocated when the group is created.
14191 @item @code{system?} (default: @code{#f})
14192 This Boolean value indicates whether the group is a ``system'' group.
14193 System groups have low numerical IDs.
14195 @item @code{password} (default: @code{#f})
14196 What, user groups can have a password? Well, apparently yes. Unless
14197 @code{#f}, this field specifies the password of the group.
14202 For convenience, a variable lists all the basic user groups one may
14205 @defvr {Scheme Variable} %base-groups
14206 This is the list of basic user groups that users and/or packages expect
14207 to be present on the system. This includes groups such as ``root'',
14208 ``wheel'', and ``users'', as well as groups used to control access to
14209 specific devices such as ``audio'', ``disk'', and ``cdrom''.
14212 @defvr {Scheme Variable} %base-user-accounts
14213 This is the list of basic system accounts that programs may expect to
14214 find on a GNU/Linux system, such as the ``nobody'' account.
14216 Note that the ``root'' account is not included here. It is a
14217 special-case and is automatically added whether or not it is specified.
14220 @node Keyboard Layout
14221 @section Keyboard Layout
14223 @cindex keyboard layout
14225 To specify what each key of your keyboard does, you need to tell the operating
14226 system what @dfn{keyboard layout} you want to use. The default, when nothing
14227 is specified, is the US English QWERTY layout for 105-key PC keyboards.
14228 However, German speakers will usually prefer the German QWERTZ layout, French
14229 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
14230 or bépo, and they might even want to further customize the effect of some of
14231 the keys. This section explains how to get that done.
14233 @cindex keyboard layout, definition
14234 There are three components that will want to know about your keyboard layout:
14238 The @emph{bootloader} may want to know what keyboard layout you want to use
14239 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
14240 you want, for instance, to make sure that you can type the passphrase of your
14241 encrypted root partition using the right layout.
14244 The @emph{operating system kernel}, Linux, will need that so that the console
14245 is properly configured (@pxref{operating-system Reference,
14246 @code{keyboard-layout}}).
14249 The @emph{graphical display server}, usually Xorg, also has its own idea of
14250 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
14253 Guix allows you to configure all three separately but, fortunately, it allows
14254 you to share the same keyboard layout for all three components.
14256 @cindex XKB, keyboard layouts
14257 Keyboard layouts are represented by records created by the
14258 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
14259 the X Keyboard extension (XKB), each layout has four attributes: a name (often
14260 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
14261 optional variant name, an optional keyboard model name, and a possibly empty
14262 list of additional options. In most cases the layout name is all you care
14265 @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
14266 [#:model] [#:options '()]
14267 Return a new keyboard layout with the given @var{name} and @var{variant}.
14269 @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
14270 string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
14271 @code{xkeyboard-config} package for valid options.
14274 Here are a few examples:
14277 ;; The German QWERTZ layout. Here we assume a standard
14278 ;; "pc105" keyboard model.
14279 (keyboard-layout "de")
14281 ;; The bépo variant of the French layout.
14282 (keyboard-layout "fr" "bepo")
14284 ;; The Catalan layout.
14285 (keyboard-layout "es" "cat")
14287 ;; Arabic layout with "Alt-Shift" to switch to US layout.
14288 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
14290 ;; The Latin American Spanish layout. In addition, the
14291 ;; "Caps Lock" key is used as an additional "Ctrl" key,
14292 ;; and the "Menu" key is used as a "Compose" key to enter
14293 ;; accented letters.
14294 (keyboard-layout "latam"
14295 #:options '("ctrl:nocaps" "compose:menu"))
14297 ;; The Russian layout for a ThinkPad keyboard.
14298 (keyboard-layout "ru" #:model "thinkpad")
14300 ;; The "US international" layout, which is the US layout plus
14301 ;; dead keys to enter accented characters. This is for an
14302 ;; Apple MacBook keyboard.
14303 (keyboard-layout "us" "intl" #:model "macbook78")
14306 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
14307 for a complete list of supported layouts, variants, and models.
14309 @cindex keyboard layout, configuration
14310 Let's say you want your system to use the Turkish keyboard layout throughout
14311 your system---bootloader, console, and Xorg. Here's what your system
14312 configuration would look like:
14314 @findex set-xorg-configuration
14316 ;; Using the Turkish layout for the bootloader, the console,
14321 (keyboard-layout (keyboard-layout "tr")) ;for the console
14322 (bootloader (bootloader-configuration
14323 (bootloader grub-efi-bootloader)
14324 (target "/boot/efi")
14325 (keyboard-layout keyboard-layout))) ;for GRUB
14326 (services (cons (set-xorg-configuration
14327 (xorg-configuration ;for Xorg
14328 (keyboard-layout keyboard-layout)))
14329 %desktop-services)))
14332 In the example above, for GRUB and for Xorg, we just refer to the
14333 @code{keyboard-layout} field defined above, but we could just as well refer to
14334 a different layout. The @code{set-xorg-configuration} procedure communicates
14335 the desired Xorg configuration to the graphical log-in manager, by default
14338 We've discussed how to specify the @emph{default} keyboard layout of your
14339 system when it starts, but you can also adjust it at run time:
14343 If you're using GNOME, its settings panel has a ``Region & Language'' entry
14344 where you can select one or more keyboard layouts.
14347 Under Xorg, the @command{setxkbmap} command (from the same-named package)
14348 allows you to change the current layout. For example, this is how you would
14349 change the layout to US Dvorak:
14352 setxkbmap us dvorak
14356 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
14357 console. However, note that @code{loadkeys} does @emph{not} use the XKB
14358 keyboard layout categorization described above. The command below loads the
14359 French bépo layout:
14370 A @dfn{locale} defines cultural conventions for a particular language
14371 and region of the world (@pxref{Locales,,, libc, The GNU C Library
14372 Reference Manual}). Each locale has a name that typically has the form
14373 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
14374 @code{fr_LU.utf8} designates the locale for the French language, with
14375 cultural conventions from Luxembourg, and using the UTF-8 encoding.
14377 @cindex locale definition
14378 Usually, you will want to specify the default locale for the machine
14379 using the @code{locale} field of the @code{operating-system} declaration
14380 (@pxref{operating-system Reference, @code{locale}}).
14382 The selected locale is automatically added to the @dfn{locale
14383 definitions} known to the system if needed, with its codeset inferred
14384 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
14385 @code{UTF-8} codeset. Additional locale definitions can be specified in
14386 the @code{locale-definitions} slot of @code{operating-system}---this is
14387 useful, for instance, if the codeset could not be inferred from the
14388 locale name. The default set of locale definitions includes some widely
14389 used locales, but not all the available locales, in order to save space.
14391 For instance, to add the North Frisian locale for Germany, the value of
14395 (cons (locale-definition
14396 (name "fy_DE.utf8") (source "fy_DE"))
14397 %default-locale-definitions)
14400 Likewise, to save space, one might want @code{locale-definitions} to
14401 list only the locales that are actually used, as in:
14404 (list (locale-definition
14405 (name "ja_JP.eucjp") (source "ja_JP")
14406 (charset "EUC-JP")))
14410 The compiled locale definitions are available at
14411 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
14412 version, which is the default location where the GNU@tie{}libc provided
14413 by Guix looks for locale data. This can be overridden using the
14414 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
14415 @env{LOCPATH} and locale packages}).
14417 The @code{locale-definition} form is provided by the @code{(gnu system
14418 locale)} module. Details are given below.
14420 @deftp {Data Type} locale-definition
14421 This is the data type of a locale definition.
14426 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
14427 Reference Manual}, for more information on locale names.
14429 @item @code{source}
14430 The name of the source for that locale. This is typically the
14431 @code{@var{language}_@var{territory}} part of the locale name.
14433 @item @code{charset} (default: @code{"UTF-8"})
14434 The ``character set'' or ``code set'' for that locale,
14435 @uref{https://www.iana.org/assignments/character-sets, as defined by
14441 @defvr {Scheme Variable} %default-locale-definitions
14442 A list of commonly used UTF-8 locales, used as the default
14443 value of the @code{locale-definitions} field of @code{operating-system}
14446 @cindex locale name
14447 @cindex normalized codeset in locale names
14448 These locale definitions use the @dfn{normalized codeset} for the part
14449 that follows the dot in the name (@pxref{Using gettextized software,
14450 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
14451 instance it has @code{uk_UA.utf8} but @emph{not}, say,
14452 @code{uk_UA.UTF-8}.
14455 @subsection Locale Data Compatibility Considerations
14457 @cindex incompatibility, of locale data
14458 @code{operating-system} declarations provide a @code{locale-libcs} field
14459 to specify the GNU@tie{}libc packages that are used to compile locale
14460 declarations (@pxref{operating-system Reference}). ``Why would I
14461 care?'', you may ask. Well, it turns out that the binary format of
14462 locale data is occasionally incompatible from one libc version to
14465 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
14466 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
14467 For instance, a program linked against libc version 2.21 is unable to
14468 read locale data produced with libc 2.22; worse, that program
14469 @emph{aborts} instead of simply ignoring the incompatible locale
14470 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
14471 the incompatible locale data, which is already an improvement.}.
14472 Similarly, a program linked against libc 2.22 can read most, but not
14473 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
14474 data is incompatible); thus calls to @code{setlocale} may fail, but
14475 programs will not abort.
14477 The ``problem'' with Guix is that users have a lot of freedom: They can
14478 choose whether and when to upgrade software in their profiles, and might
14479 be using a libc version different from the one the system administrator
14480 used to build the system-wide locale data.
14482 Fortunately, unprivileged users can also install their own locale data
14483 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
14484 @env{GUIX_LOCPATH} and locale packages}).
14486 Still, it is best if the system-wide locale data at
14487 @file{/run/current-system/locale} is built for all the libc versions
14488 actually in use on the system, so that all the programs can access
14489 it---this is especially crucial on a multi-user system. To do that, the
14490 administrator can specify several libc packages in the
14491 @code{locale-libcs} field of @code{operating-system}:
14494 (use-package-modules base)
14498 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
14501 This example would lead to a system containing locale definitions for
14502 both libc 2.21 and the current version of libc in
14503 @file{/run/current-system/locale}.
14509 @cindex system services
14510 An important part of preparing an @code{operating-system} declaration is
14511 listing @dfn{system services} and their configuration (@pxref{Using the
14512 Configuration System}). System services are typically daemons launched
14513 when the system boots, or other actions needed at that time---e.g.,
14514 configuring network access.
14516 Guix has a broad definition of ``service'' (@pxref{Service
14517 Composition}), but many services are managed by the GNU@tie{}Shepherd
14518 (@pxref{Shepherd Services}). On a running system, the @command{herd}
14519 command allows you to list the available services, show their status,
14520 start and stop them, or do other specific operations (@pxref{Jump
14521 Start,,, shepherd, The GNU Shepherd Manual}). For example:
14527 The above command, run as @code{root}, lists the currently defined
14528 services. The @command{herd doc} command shows a synopsis of the given
14529 service and its associated actions:
14533 Run libc's name service cache daemon (nscd).
14535 # herd doc nscd action invalidate
14536 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
14539 The @command{start}, @command{stop}, and @command{restart} sub-commands
14540 have the effect you would expect. For instance, the commands below stop
14541 the nscd service and restart the Xorg display server:
14545 Service nscd has been stopped.
14546 # herd restart xorg-server
14547 Service xorg-server has been stopped.
14548 Service xorg-server has been started.
14551 The following sections document the available services, starting with
14552 the core services, that may be used in an @code{operating-system}
14556 * Base Services:: Essential system services.
14557 * Scheduled Job Execution:: The mcron service.
14558 * Log Rotation:: The rottlog service.
14559 * Networking Services:: Network setup, SSH daemon, etc.
14560 * Unattended Upgrades:: Automated system upgrades.
14561 * X Window:: Graphical display.
14562 * Printing Services:: Local and remote printer support.
14563 * Desktop Services:: D-Bus and desktop services.
14564 * Sound Services:: ALSA and Pulseaudio services.
14565 * Database Services:: SQL databases, key-value stores, etc.
14566 * Mail Services:: IMAP, POP3, SMTP, and all that.
14567 * Messaging Services:: Messaging services.
14568 * Telephony Services:: Telephony services.
14569 * Monitoring Services:: Monitoring services.
14570 * Kerberos Services:: Kerberos services.
14571 * LDAP Services:: LDAP services.
14572 * Web Services:: Web servers.
14573 * Certificate Services:: TLS certificates via Let's Encrypt.
14574 * DNS Services:: DNS daemons.
14575 * VPN Services:: VPN daemons.
14576 * Network File System:: NFS related services.
14577 * Continuous Integration:: The Cuirass service.
14578 * Power Management Services:: Extending battery life.
14579 * Audio Services:: The MPD.
14580 * Virtualization Services:: Virtualization services.
14581 * Version Control Services:: Providing remote access to Git repositories.
14582 * Game Services:: Game servers.
14583 * PAM Mount Service:: Service to mount volumes when logging in.
14584 * Guix Services:: Services relating specifically to Guix.
14585 * Linux Services:: Services tied to the Linux kernel.
14586 * Hurd Services:: Services specific for a Hurd System.
14587 * Miscellaneous Services:: Other services.
14590 @node Base Services
14591 @subsection Base Services
14593 The @code{(gnu services base)} module provides definitions for the basic
14594 services that one expects from the system. The services exported by
14595 this module are listed below.
14597 @defvr {Scheme Variable} %base-services
14598 This variable contains a list of basic services (@pxref{Service Types
14599 and Services}, for more information on service objects) one would
14600 expect from the system: a login service (mingetty) on each tty, syslogd,
14601 the libc name service cache daemon (nscd), the udev device manager, and
14604 This is the default value of the @code{services} field of
14605 @code{operating-system} declarations. Usually, when customizing a
14606 system, you will want to append services to @code{%base-services}, like
14610 (append (list (service avahi-service-type)
14611 (service openssh-service-type))
14616 @defvr {Scheme Variable} special-files-service-type
14617 This is the service that sets up ``special files'' such as
14618 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
14620 The value associated with @code{special-files-service-type} services
14621 must be a list of tuples where the first element is the ``special file''
14622 and the second element is its target. By default it is:
14624 @cindex @file{/bin/sh}
14625 @cindex @file{sh}, in @file{/bin}
14627 `(("/bin/sh" ,(file-append bash "/bin/sh")))
14630 @cindex @file{/usr/bin/env}
14631 @cindex @file{env}, in @file{/usr/bin}
14632 If you want to add, say, @code{/usr/bin/env} to your system, you can
14636 `(("/bin/sh" ,(file-append bash "/bin/sh"))
14637 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
14640 Since this is part of @code{%base-services}, you can use
14641 @code{modify-services} to customize the set of special files
14642 (@pxref{Service Reference, @code{modify-services}}). But the simple way
14643 to add a special file is @i{via} the @code{extra-special-file} procedure
14647 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
14648 Use @var{target} as the ``special file'' @var{file}.
14650 For example, adding the following lines to the @code{services} field of
14651 your operating system declaration leads to a @file{/usr/bin/env}
14655 (extra-special-file "/usr/bin/env"
14656 (file-append coreutils "/bin/env"))
14660 @deffn {Scheme Procedure} host-name-service @var{name}
14661 Return a service that sets the host name to @var{name}.
14664 @defvr {Scheme Variable} console-font-service-type
14665 Install the given fonts on the specified ttys (fonts are per
14666 virtual console on the kernel Linux). The value of this service is a list of
14667 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
14668 package or any valid argument to @command{setfont}, as in this example:
14671 `(("tty1" . "LatGrkCyr-8x16")
14672 ("tty2" . ,(file-append
14674 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
14675 ("tty3" . ,(file-append
14677 "/share/consolefonts/ter-132n"))) ; for HDPI
14681 @deffn {Scheme Procedure} login-service @var{config}
14682 Return a service to run login according to @var{config}, a
14683 @code{<login-configuration>} object, which specifies the message of the day,
14684 among other things.
14687 @deftp {Data Type} login-configuration
14688 This is the data type representing the configuration of login.
14693 @cindex message of the day
14694 A file-like object containing the ``message of the day''.
14696 @item @code{allow-empty-passwords?} (default: @code{#t})
14697 Allow empty passwords by default so that first-time users can log in when
14698 the 'root' account has just been created.
14703 @deffn {Scheme Procedure} mingetty-service @var{config}
14704 Return a service to run mingetty according to @var{config}, a
14705 @code{<mingetty-configuration>} object, which specifies the tty to run, among
14709 @deftp {Data Type} mingetty-configuration
14710 This is the data type representing the configuration of Mingetty, which
14711 provides the default implementation of virtual console log-in.
14716 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
14718 @item @code{auto-login} (default: @code{#f})
14719 When true, this field must be a string denoting the user name under
14720 which the system automatically logs in. When it is @code{#f}, a
14721 user name and password must be entered to log in.
14723 @item @code{login-program} (default: @code{#f})
14724 This must be either @code{#f}, in which case the default log-in program
14725 is used (@command{login} from the Shadow tool suite), or a gexp denoting
14726 the name of the log-in program.
14728 @item @code{login-pause?} (default: @code{#f})
14729 When set to @code{#t} in conjunction with @var{auto-login}, the user
14730 will have to press a key before the log-in shell is launched.
14732 @item @code{clear-on-logout?} (default: @code{#t})
14733 When set to @code{#t}, the screen will be cleared after logout.
14735 @item @code{mingetty} (default: @var{mingetty})
14736 The Mingetty package to use.
14741 @deffn {Scheme Procedure} agetty-service @var{config}
14742 Return a service to run agetty according to @var{config}, an
14743 @code{<agetty-configuration>} object, which specifies the tty to run,
14744 among other things.
14747 @deftp {Data Type} agetty-configuration
14748 This is the data type representing the configuration of agetty, which
14749 implements virtual and serial console log-in. See the @code{agetty(8)}
14750 man page for more information.
14755 The name of the console this agetty runs on, as a string---e.g.,
14756 @code{"ttyS0"}. This argument is optional, it will default to
14757 a reasonable default serial port used by the kernel Linux.
14759 For this, if there is a value for an option @code{agetty.tty} in the kernel
14760 command line, agetty will extract the device name of the serial port
14761 from it and use that.
14763 If not and if there is a value for an option @code{console} with a tty in
14764 the Linux command line, agetty will extract the device name of the
14765 serial port from it and use that.
14767 In both cases, agetty will leave the other serial device settings
14768 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
14771 @item @code{baud-rate} (default: @code{#f})
14772 A string containing a comma-separated list of one or more baud rates, in
14775 @item @code{term} (default: @code{#f})
14776 A string containing the value used for the @env{TERM} environment
14779 @item @code{eight-bits?} (default: @code{#f})
14780 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
14783 @item @code{auto-login} (default: @code{#f})
14784 When passed a login name, as a string, the specified user will be logged
14785 in automatically without prompting for their login name or password.
14787 @item @code{no-reset?} (default: @code{#f})
14788 When @code{#t}, don't reset terminal cflags (control modes).
14790 @item @code{host} (default: @code{#f})
14791 This accepts a string containing the ``login_host'', which will be written
14792 into the @file{/var/run/utmpx} file.
14794 @item @code{remote?} (default: @code{#f})
14795 When set to @code{#t} in conjunction with @var{host}, this will add an
14796 @code{-r} fakehost option to the command line of the login program
14797 specified in @var{login-program}.
14799 @item @code{flow-control?} (default: @code{#f})
14800 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
14802 @item @code{no-issue?} (default: @code{#f})
14803 When set to @code{#t}, the contents of the @file{/etc/issue} file will
14804 not be displayed before presenting the login prompt.
14806 @item @code{init-string} (default: @code{#f})
14807 This accepts a string that will be sent to the tty or modem before
14808 sending anything else. It can be used to initialize a modem.
14810 @item @code{no-clear?} (default: @code{#f})
14811 When set to @code{#t}, agetty will not clear the screen before showing
14814 @item @code{login-program} (default: (file-append shadow "/bin/login"))
14815 This must be either a gexp denoting the name of a log-in program, or
14816 unset, in which case the default value is the @command{login} from the
14819 @item @code{local-line} (default: @code{#f})
14820 Control the CLOCAL line flag. This accepts one of three symbols as
14821 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
14822 the default value chosen by agetty is @code{'auto}.
14824 @item @code{extract-baud?} (default: @code{#f})
14825 When set to @code{#t}, instruct agetty to try to extract the baud rate
14826 from the status messages produced by certain types of modems.
14828 @item @code{skip-login?} (default: @code{#f})
14829 When set to @code{#t}, do not prompt the user for a login name. This
14830 can be used with @var{login-program} field to use non-standard login
14833 @item @code{no-newline?} (default: @code{#f})
14834 When set to @code{#t}, do not print a newline before printing the
14835 @file{/etc/issue} file.
14837 @c Is this dangerous only when used with login-program, or always?
14838 @item @code{login-options} (default: @code{#f})
14839 This option accepts a string containing options that are passed to the
14840 login program. When used with the @var{login-program}, be aware that a
14841 malicious user could try to enter a login name containing embedded
14842 options that could be parsed by the login program.
14844 @item @code{login-pause} (default: @code{#f})
14845 When set to @code{#t}, wait for any key before showing the login prompt.
14846 This can be used in conjunction with @var{auto-login} to save memory by
14847 lazily spawning shells.
14849 @item @code{chroot} (default: @code{#f})
14850 Change root to the specified directory. This option accepts a directory
14853 @item @code{hangup?} (default: @code{#f})
14854 Use the Linux system call @code{vhangup} to do a virtual hangup of the
14855 specified terminal.
14857 @item @code{keep-baud?} (default: @code{#f})
14858 When set to @code{#t}, try to keep the existing baud rate. The baud
14859 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
14862 @item @code{timeout} (default: @code{#f})
14863 When set to an integer value, terminate if no user name could be read
14864 within @var{timeout} seconds.
14866 @item @code{detect-case?} (default: @code{#f})
14867 When set to @code{#t}, turn on support for detecting an uppercase-only
14868 terminal. This setting will detect a login name containing only
14869 uppercase letters as indicating an uppercase-only terminal and turn on
14870 some upper-to-lower case conversions. Note that this will not support
14871 Unicode characters.
14873 @item @code{wait-cr?} (default: @code{#f})
14874 When set to @code{#t}, wait for the user or modem to send a
14875 carriage-return or linefeed character before displaying
14876 @file{/etc/issue} or login prompt. This is typically used with the
14877 @var{init-string} option.
14879 @item @code{no-hints?} (default: @code{#f})
14880 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
14883 @item @code{no-hostname?} (default: @code{#f})
14884 By default, the hostname is printed. When this option is set to
14885 @code{#t}, no hostname will be shown at all.
14887 @item @code{long-hostname?} (default: @code{#f})
14888 By default, the hostname is only printed until the first dot. When this
14889 option is set to @code{#t}, the fully qualified hostname by
14890 @code{gethostname} or @code{getaddrinfo} is shown.
14892 @item @code{erase-characters} (default: @code{#f})
14893 This option accepts a string of additional characters that should be
14894 interpreted as backspace when the user types their login name.
14896 @item @code{kill-characters} (default: @code{#f})
14897 This option accepts a string that should be interpreted to mean ``ignore
14898 all previous characters'' (also called a ``kill'' character) when the user
14899 types their login name.
14901 @item @code{chdir} (default: @code{#f})
14902 This option accepts, as a string, a directory path that will be changed
14905 @item @code{delay} (default: @code{#f})
14906 This options accepts, as an integer, the number of seconds to sleep
14907 before opening the tty and displaying the login prompt.
14909 @item @code{nice} (default: @code{#f})
14910 This option accepts, as an integer, the nice value with which to run the
14911 @command{login} program.
14913 @item @code{extra-options} (default: @code{'()})
14914 This option provides an ``escape hatch'' for the user to provide arbitrary
14915 command-line arguments to @command{agetty} as a list of strings.
14920 @deffn {Scheme Procedure} kmscon-service-type @var{config}
14921 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
14922 according to @var{config}, a @code{<kmscon-configuration>} object, which
14923 specifies the tty to run, among other things.
14926 @deftp {Data Type} kmscon-configuration
14927 This is the data type representing the configuration of Kmscon, which
14928 implements virtual console log-in.
14932 @item @code{virtual-terminal}
14933 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
14935 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
14936 A gexp denoting the name of the log-in program. The default log-in program is
14937 @command{login} from the Shadow tool suite.
14939 @item @code{login-arguments} (default: @code{'("-p")})
14940 A list of arguments to pass to @command{login}.
14942 @item @code{auto-login} (default: @code{#f})
14943 When passed a login name, as a string, the specified user will be logged
14944 in automatically without prompting for their login name or password.
14946 @item @code{hardware-acceleration?} (default: #f)
14947 Whether to use hardware acceleration.
14949 @item @code{kmscon} (default: @var{kmscon})
14950 The Kmscon package to use.
14955 @cindex name service cache daemon
14957 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
14958 [#:name-services '()]
14959 Return a service that runs the libc name service cache daemon (nscd) with the
14960 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
14961 Service Switch}, for an example.
14963 For convenience, the Shepherd service for nscd provides the following actions:
14967 @cindex cache invalidation, nscd
14968 @cindex nscd, cache invalidation
14969 This invalidate the given cache. For instance, running:
14972 herd invalidate nscd hosts
14976 invalidates the host name lookup cache of nscd.
14979 Running @command{herd statistics nscd} displays information about nscd usage
14985 @defvr {Scheme Variable} %nscd-default-configuration
14986 This is the default @code{<nscd-configuration>} value (see below) used
14987 by @code{nscd-service}. It uses the caches defined by
14988 @code{%nscd-default-caches}; see below.
14991 @deftp {Data Type} nscd-configuration
14992 This is the data type representing the name service cache daemon (nscd)
14997 @item @code{name-services} (default: @code{'()})
14998 List of packages denoting @dfn{name services} that must be visible to
14999 the nscd---e.g., @code{(list @var{nss-mdns})}.
15001 @item @code{glibc} (default: @var{glibc})
15002 Package object denoting the GNU C Library providing the @command{nscd}
15005 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
15006 Name of the nscd log file. This is where debugging output goes when
15007 @code{debug-level} is strictly positive.
15009 @item @code{debug-level} (default: @code{0})
15010 Integer denoting the debugging levels. Higher numbers mean that more
15011 debugging output is logged.
15013 @item @code{caches} (default: @code{%nscd-default-caches})
15014 List of @code{<nscd-cache>} objects denoting things to be cached; see
15020 @deftp {Data Type} nscd-cache
15021 Data type representing a cache database of nscd and its parameters.
15025 @item @code{database}
15026 This is a symbol representing the name of the database to be cached.
15027 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
15028 @code{services}, which designate the corresponding NSS database
15029 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
15031 @item @code{positive-time-to-live}
15032 @itemx @code{negative-time-to-live} (default: @code{20})
15033 A number representing the number of seconds during which a positive or
15034 negative lookup result remains in cache.
15036 @item @code{check-files?} (default: @code{#t})
15037 Whether to check for updates of the files corresponding to
15040 For instance, when @var{database} is @code{hosts}, setting this flag
15041 instructs nscd to check for updates in @file{/etc/hosts} and to take
15044 @item @code{persistent?} (default: @code{#t})
15045 Whether the cache should be stored persistently on disk.
15047 @item @code{shared?} (default: @code{#t})
15048 Whether the cache should be shared among users.
15050 @item @code{max-database-size} (default: 32@tie{}MiB)
15051 Maximum size in bytes of the database cache.
15053 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
15054 @c settings, so leave them out.
15059 @defvr {Scheme Variable} %nscd-default-caches
15060 List of @code{<nscd-cache>} objects used by default by
15061 @code{nscd-configuration} (see above).
15063 It enables persistent and aggressive caching of service and host name
15064 lookups. The latter provides better host name lookup performance,
15065 resilience in the face of unreliable name servers, and also better
15066 privacy---often the result of host name lookups is in local cache, so
15067 external name servers do not even need to be queried.
15070 @anchor{syslog-configuration-type}
15073 @deftp {Data Type} syslog-configuration
15074 This data type represents the configuration of the syslog daemon.
15077 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
15078 The syslog daemon to use.
15080 @item @code{config-file} (default: @code{%default-syslog.conf})
15081 The syslog configuration file to use.
15086 @anchor{syslog-service}
15088 @deffn {Scheme Procedure} syslog-service @var{config}
15089 Return a service that runs a syslog daemon according to @var{config}.
15091 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
15092 information on the configuration file syntax.
15095 @defvr {Scheme Variable} guix-service-type
15096 This is the type of the service that runs the build daemon,
15097 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
15098 @code{guix-configuration} record as described below.
15101 @anchor{guix-configuration-type}
15102 @deftp {Data Type} guix-configuration
15103 This data type represents the configuration of the Guix build daemon.
15104 @xref{Invoking guix-daemon}, for more information.
15107 @item @code{guix} (default: @var{guix})
15108 The Guix package to use.
15110 @item @code{build-group} (default: @code{"guixbuild"})
15111 Name of the group for build user accounts.
15113 @item @code{build-accounts} (default: @code{10})
15114 Number of build user accounts to create.
15116 @item @code{authorize-key?} (default: @code{#t})
15117 @cindex substitutes, authorization thereof
15118 Whether to authorize the substitute keys listed in
15119 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
15120 (@pxref{Substitutes}).
15122 When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
15123 changed by invoking @command{guix archive --authorize}. You must
15124 instead adjust @code{guix-configuration} as you wish and reconfigure the
15125 system. This ensures that your operating system configuration file is
15129 When booting or reconfiguring to a system where @code{authorize-key?}
15130 is true, the existing @file{/etc/guix/acl} file is backed up as
15131 @file{/etc/guix/acl.bak} if it was determined to be a manually modified
15132 file. This is to facilitate migration from earlier versions, which
15133 allowed for in-place modifications to @file{/etc/guix/acl}.
15136 @vindex %default-authorized-guix-keys
15137 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
15138 The list of authorized key files for archive imports, as a list of
15139 string-valued gexps (@pxref{Invoking guix archive}). By default, it
15140 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
15141 See @code{substitute-urls} below for an example on how to change it.
15143 @item @code{use-substitutes?} (default: @code{#t})
15144 Whether to use substitutes.
15146 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
15147 The list of URLs where to look for substitutes by default.
15149 Suppose you would like to fetch substitutes from @code{guix.example.org}
15150 in addition to @code{@value{SUBSTITUTE-SERVER}}. You will need to do
15151 two things: (1) add @code{guix.example.org} to @code{substitute-urls},
15152 and (2) authorize its signing key, having done appropriate checks
15153 (@pxref{Substitute Server Authorization}). The configuration below does
15157 (guix-configuration
15159 (append (list "https://guix.example.org")
15160 %default-substitute-urls))
15162 (append (list (local-file "./guix.example.org-key.pub"))
15163 %default-authorized-guix-keys)))
15166 This example assumes that the file @file{./guix.example.org-key.pub}
15167 contains the public key that @code{guix.example.org} uses to sign
15170 @item @code{max-silent-time} (default: @code{0})
15171 @itemx @code{timeout} (default: @code{0})
15172 The number of seconds of silence and the number of seconds of activity,
15173 respectively, after which a build process times out. A value of zero
15174 disables the timeout.
15176 @item @code{log-compression} (default: @code{'bzip2})
15177 The type of compression used for build logs---one of @code{gzip},
15178 @code{bzip2}, or @code{none}.
15180 @item @code{discover?} (default: @code{#f})
15181 Whether to discover substitute servers on the local network using mDNS
15184 @item @code{extra-options} (default: @code{'()})
15185 List of extra command-line options for @command{guix-daemon}.
15187 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
15188 File where @command{guix-daemon}'s standard output and standard error
15191 @cindex HTTP proxy, for @code{guix-daemon}
15192 @cindex proxy, for @code{guix-daemon} HTTP access
15193 @item @code{http-proxy} (default: @code{#f})
15194 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
15195 derivations and substitutes.
15197 It is also possible to change the daemon's proxy at run time through the
15198 @code{set-http-proxy} action, which restarts it:
15201 herd set-http-proxy guix-daemon http://localhost:8118
15204 To clear the proxy settings, run:
15207 herd set-http-proxy guix-daemon
15210 @item @code{tmpdir} (default: @code{#f})
15211 A directory path where the @command{guix-daemon} will perform builds.
15216 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
15217 Run @var{udev}, which populates the @file{/dev} directory dynamically.
15218 udev rules can be provided as a list of files through the @var{rules}
15219 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
15220 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
15221 creation of such rule files.
15223 The @command{herd rules udev} command, as root, returns the name of the
15224 directory containing all the active udev rules.
15227 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
15228 Return a udev-rule file named @var{file-name} containing the rules
15229 defined by the @var{contents} literal.
15231 In the following example, a rule for a USB device is defined to be
15232 stored in the file @file{90-usb-thing.rules}. The rule runs a script
15233 upon detecting a USB device with a given product identifier.
15236 (define %example-udev-rule
15238 "90-usb-thing.rules"
15239 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
15240 "ATTR@{product@}==\"Example\", "
15241 "RUN+=\"/path/to/script\"")))
15245 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
15246 [#:groups @var{groups}]
15247 Return a service that extends @code{udev-service-type } with @var{rules}
15248 and @code{account-service-type} with @var{groups} as system groups.
15249 This works by creating a singleton service type
15250 @code{@var{name}-udev-rules}, of which the returned service is an
15253 Here we show how it can be used to extend @code{udev-service-type} with the
15254 previously defined rule @code{%example-udev-rule}.
15260 (cons (udev-rules-service 'usb-thing %example-udev-rule)
15261 %desktop-services)))
15265 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
15266 Return a udev file named @var{file-name} containing the rules defined
15267 within @var{file}, a file-like object.
15269 The following example showcases how we can use an existing rule file.
15272 (use-modules (guix download) ;for url-fetch
15273 (guix packages) ;for origin
15276 (define %android-udev-rules
15278 "51-android-udev.rules"
15279 (let ((version "20170910"))
15282 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
15283 "android-udev-rules/" version "/51-android.rules"))
15285 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
15289 Additionally, Guix package definitions can be included in @var{rules} in
15290 order to extend the udev rules with the definitions found under their
15291 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
15292 @var{file->udev-rule} example, we could have used the
15293 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
15294 packages android)} module.
15296 The following example shows how to use the @var{android-udev-rules}
15297 package so that the Android tool @command{adb} can detect devices
15298 without root privileges. It also details how to create the
15299 @code{adbusers} group, which is required for the proper functioning of
15300 the rules defined within the @code{android-udev-rules} package. To
15301 create such a group, we must define it both as part of the
15302 @code{supplementary-groups} of our @code{user-account} declaration, as
15303 well as in the @var{groups} of the @code{udev-rules-service} procedure.
15306 (use-modules (gnu packages android) ;for android-udev-rules
15307 (gnu system shadow) ;for user-group
15312 (users (cons (user-account
15314 (supplementary-groups
15315 '("adbusers" ;for adb
15316 "wheel" "netdev" "audio" "video")))))
15319 (cons (udev-rules-service 'android android-udev-rules
15320 #:groups '("adbusers"))
15321 %desktop-services)))
15324 @defvr {Scheme Variable} urandom-seed-service-type
15325 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
15326 when rebooting. It also tries to seed @file{/dev/urandom} from
15327 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
15331 @defvr {Scheme Variable} %random-seed-file
15332 This is the name of the file where some random bytes are saved by
15333 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
15334 It defaults to @file{/var/lib/random-seed}.
15339 @defvr {Scheme Variable} gpm-service-type
15340 This is the type of the service that runs GPM, the @dfn{general-purpose
15341 mouse daemon}, which provides mouse support to the Linux console. GPM
15342 allows users to use the mouse in the console, notably to select, copy,
15345 The value for services of this type must be a @code{gpm-configuration}
15346 (see below). This service is not part of @code{%base-services}.
15349 @deftp {Data Type} gpm-configuration
15350 Data type representing the configuration of GPM.
15353 @item @code{options} (default: @code{%default-gpm-options})
15354 Command-line options passed to @command{gpm}. The default set of
15355 options instruct @command{gpm} to listen to mouse events on
15356 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
15359 @item @code{gpm} (default: @code{gpm})
15360 The GPM package to use.
15365 @anchor{guix-publish-service-type}
15366 @deffn {Scheme Variable} guix-publish-service-type
15367 This is the service type for @command{guix publish} (@pxref{Invoking
15368 guix publish}). Its value must be a @code{guix-publish-configuration}
15369 object, as described below.
15371 This assumes that @file{/etc/guix} already contains a signing key pair as
15372 created by @command{guix archive --generate-key} (@pxref{Invoking guix
15373 archive}). If that is not the case, the service will fail to start.
15376 @deftp {Data Type} guix-publish-configuration
15377 Data type representing the configuration of the @code{guix publish}
15381 @item @code{guix} (default: @code{guix})
15382 The Guix package to use.
15384 @item @code{port} (default: @code{80})
15385 The TCP port to listen for connections.
15387 @item @code{host} (default: @code{"localhost"})
15388 The host (and thus, network interface) to listen to. Use
15389 @code{"0.0.0.0"} to listen on all the network interfaces.
15391 @item @code{advertise?} (default: @code{#f})
15392 When true, advertise the service on the local network @i{via} the DNS-SD
15393 protocol, using Avahi.
15395 This allows neighboring Guix devices with discovery on (see
15396 @code{guix-configuration} above) to discover this @command{guix publish}
15397 instance and to automatically download substitutes from it.
15399 @item @code{compression} (default: @code{'(("gzip" 3))})
15400 This is a list of compression method/level tuple used when compressing
15401 substitutes. For example, to compress all substitutes with @emph{both} lzip
15402 at level 7 and gzip at level 9, write:
15405 '(("lzip" 7) ("gzip" 9))
15408 Level 9 achieves the best compression ratio at the expense of increased CPU
15409 usage, whereas level 1 achieves fast compression. @xref{Invoking guix
15410 publish}, for more information on the available compression methods and
15411 the tradeoffs involved.
15413 An empty list disables compression altogether.
15415 @item @code{nar-path} (default: @code{"nar"})
15416 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
15417 publish, @option{--nar-path}}, for details.
15419 @item @code{cache} (default: @code{#f})
15420 When it is @code{#f}, disable caching and instead generate archives on
15421 demand. Otherwise, this should be the name of a directory---e.g.,
15422 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
15423 archives and meta-data ready to be sent. @xref{Invoking guix publish,
15424 @option{--cache}}, for more information on the tradeoffs involved.
15426 @item @code{workers} (default: @code{#f})
15427 When it is an integer, this is the number of worker threads used for
15428 caching; when @code{#f}, the number of processors is used.
15429 @xref{Invoking guix publish, @option{--workers}}, for more information.
15431 @item @code{cache-bypass-threshold} (default: 10 MiB)
15432 When @code{cache} is true, this is the maximum size in bytes of a store
15433 item for which @command{guix publish} may bypass its cache in case of a
15434 cache miss. @xref{Invoking guix publish,
15435 @option{--cache-bypass-threshold}}, for more information.
15437 @item @code{ttl} (default: @code{#f})
15438 When it is an integer, this denotes the @dfn{time-to-live} in seconds
15439 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
15440 for more information.
15444 @anchor{rngd-service}
15445 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
15446 [#:device "/dev/hwrng"]
15447 Return a service that runs the @command{rngd} program from @var{rng-tools}
15448 to add @var{device} to the kernel's entropy pool. The service will fail if
15449 @var{device} does not exist.
15452 @anchor{pam-limits-service}
15453 @cindex session limits
15458 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
15460 Return a service that installs a configuration file for the
15461 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
15462 @code{pam_limits} module}. The procedure optionally takes a list of
15463 @code{pam-limits-entry} values, which can be used to specify
15464 @code{ulimit} limits and nice priority limits to user sessions.
15466 The following limits definition sets two hard and soft limits for all
15467 login sessions of users in the @code{realtime} group:
15470 (pam-limits-service
15472 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
15473 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
15476 The first entry increases the maximum realtime priority for
15477 non-privileged processes; the second entry lifts any restriction of the
15478 maximum address space that can be locked in memory. These settings are
15479 commonly used for real-time audio systems.
15482 @node Scheduled Job Execution
15483 @subsection Scheduled Job Execution
15487 @cindex scheduling jobs
15488 The @code{(gnu services mcron)} module provides an interface to
15489 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
15490 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
15491 Unix @command{cron} daemon; the main difference is that it is
15492 implemented in Guile Scheme, which provides a lot of flexibility when
15493 specifying the scheduling of jobs and their actions.
15495 The example below defines an operating system that runs the
15496 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
15497 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
15498 well as the @command{mkid} command on behalf of an unprivileged user
15499 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
15500 gexps to introduce job definitions that are passed to mcron
15501 (@pxref{G-Expressions}).
15504 (use-modules (guix) (gnu) (gnu services mcron))
15505 (use-package-modules base idutils)
15507 (define updatedb-job
15508 ;; Run 'updatedb' at 3AM every day. Here we write the
15509 ;; job's action as a Scheme procedure.
15510 #~(job '(next-hour '(3))
15512 (execl (string-append #$findutils "/bin/updatedb")
15514 "--prunepaths=/tmp /var/tmp /gnu/store"))))
15516 (define garbage-collector-job
15517 ;; Collect garbage 5 minutes after midnight every day.
15518 ;; The job's action is a shell command.
15519 #~(job "5 0 * * *" ;Vixie cron syntax
15522 (define idutils-job
15523 ;; Update the index database as user "charlie" at 12:15PM
15524 ;; and 19:15PM. This runs from the user's home directory.
15525 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
15526 (string-append #$idutils "/bin/mkid src")
15532 ;; %BASE-SERVICES already includes an instance of
15533 ;; 'mcron-service-type', which we extend with additional
15534 ;; jobs using 'simple-service'.
15535 (services (cons (simple-service 'my-cron-jobs
15537 (list garbage-collector-job
15543 For more complex jobs defined in Scheme where you need control over the top
15544 level, for instance to introduce a @code{use-modules} form, you can move your
15545 code to a separate program using the @code{program-file} procedure of the
15546 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
15550 (define %battery-alert-job
15551 ;; Beep when the battery percentage falls below %MIN-LEVEL.
15553 '(next-minute (range 0 60 1))
15555 "battery-alert.scm"
15556 (with-imported-modules (source-module-closure
15557 '((guix build utils)))
15559 (use-modules (guix build utils)
15562 (ice-9 textual-ports)
15565 (define %min-level 20)
15567 (setenv "LC_ALL" "C") ;ensure English output
15568 (and-let* ((input-pipe (open-pipe*
15570 #$(file-append acpi "/bin/acpi")))
15571 (output (get-string-all input-pipe))
15572 (m (string-match "Discharging, ([0-9]+)%" output))
15573 (level (string->number (match:substring m 1)))
15574 ((< level %min-level)))
15575 (format #t "warning: Battery level is low (~a%)~%" level)
15576 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
15579 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
15580 for more information on mcron job specifications. Below is the
15581 reference of the mcron service.
15583 On a running system, you can use the @code{schedule} action of the service to
15584 visualize the mcron jobs that will be executed next:
15587 # herd schedule mcron
15591 The example above lists the next five tasks that will be executed, but you can
15592 also specify the number of tasks to display:
15595 # herd schedule mcron 10
15598 @defvr {Scheme Variable} mcron-service-type
15599 This is the type of the @code{mcron} service, whose value is an
15600 @code{mcron-configuration} object.
15602 This service type can be the target of a service extension that provides
15603 it additional job specifications (@pxref{Service Composition}). In
15604 other words, it is possible to define services that provide additional
15608 @deftp {Data Type} mcron-configuration
15609 Data type representing the configuration of mcron.
15612 @item @code{mcron} (default: @var{mcron})
15613 The mcron package to use.
15616 This is a list of gexps (@pxref{G-Expressions}), where each gexp
15617 corresponds to an mcron job specification (@pxref{Syntax, mcron job
15618 specifications,, mcron, GNU@tie{}mcron}).
15624 @subsection Log Rotation
15627 @cindex log rotation
15629 Log files such as those found in @file{/var/log} tend to grow endlessly,
15630 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
15631 their contents in separate files, possibly compressed. The @code{(gnu
15632 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
15633 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
15635 This service is part of @code{%base-services}, and thus enabled by
15636 default, with the default settings, for commonly encountered log files.
15637 The example below shows how to extend it with an additional
15638 @dfn{rotation}, should you need to do that (usually, services that
15639 produce log files already take care of that):
15642 (use-modules (guix) (gnu))
15643 (use-service-modules admin)
15645 (define my-log-files
15646 ;; Log files that I want to rotate.
15647 '("/var/log/something.log" "/var/log/another.log"))
15651 (services (cons (simple-service 'rotate-my-stuff
15652 rottlog-service-type
15653 (list (log-rotation
15655 (files my-log-files))))
15659 @defvr {Scheme Variable} rottlog-service-type
15660 This is the type of the Rottlog service, whose value is a
15661 @code{rottlog-configuration} object.
15663 Other services can extend this one with new @code{log-rotation} objects
15664 (see below), thereby augmenting the set of files to be rotated.
15666 This service type can define mcron jobs (@pxref{Scheduled Job
15667 Execution}) to run the rottlog service.
15670 @deftp {Data Type} rottlog-configuration
15671 Data type representing the configuration of rottlog.
15674 @item @code{rottlog} (default: @code{rottlog})
15675 The Rottlog package to use.
15677 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
15678 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
15679 rottlog, GNU Rot[t]log Manual}).
15681 @item @code{rotations} (default: @code{%default-rotations})
15682 A list of @code{log-rotation} objects as defined below.
15685 This is a list of gexps where each gexp corresponds to an mcron job
15686 specification (@pxref{Scheduled Job Execution}).
15690 @deftp {Data Type} log-rotation
15691 Data type representing the rotation of a group of log files.
15693 Taking an example from the Rottlog manual (@pxref{Period Related File
15694 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
15700 (files '("/var/log/apache/*"))
15701 (options '("storedir apache-archives"
15707 The list of fields is as follows:
15710 @item @code{frequency} (default: @code{'weekly})
15711 The log rotation frequency, a symbol.
15714 The list of files or file glob patterns to rotate.
15716 @item @code{options} (default: @code{'()})
15717 The list of rottlog options for this rotation (@pxref{Configuration
15718 parameters,,, rottlog, GNU Rot[t]lg Manual}).
15720 @item @code{post-rotate} (default: @code{#f})
15721 Either @code{#f} or a gexp to execute once the rotation has completed.
15725 @defvr {Scheme Variable} %default-rotations
15726 Specifies weekly rotation of @code{%rotated-files} and of
15727 @file{/var/log/guix-daemon.log}.
15730 @defvr {Scheme Variable} %rotated-files
15731 The list of syslog-controlled files to be rotated. By default it is:
15732 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
15733 "/var/log/maillog")}.
15736 @node Networking Services
15737 @subsection Networking Services
15739 The @code{(gnu services networking)} module provides services to configure
15740 the network interface.
15742 @cindex DHCP, networking service
15743 @defvr {Scheme Variable} dhcp-client-service-type
15744 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
15745 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
15746 is the DHCP client package to use, @code{isc-dhcp} by default.
15749 @deffn {Scheme Procedure} dhcpd-service-type
15750 This type defines a service that runs a DHCP daemon. To create a
15751 service of this type, you must supply a @code{<dhcpd-configuration>}.
15755 (service dhcpd-service-type
15756 (dhcpd-configuration
15757 (config-file (local-file "my-dhcpd.conf"))
15758 (interfaces '("enp0s25"))))
15762 @deftp {Data Type} dhcpd-configuration
15764 @item @code{package} (default: @code{isc-dhcp})
15765 The package that provides the DHCP daemon. This package is expected to
15766 provide the daemon at @file{sbin/dhcpd} relative to its output
15767 directory. The default package is the
15768 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
15769 @item @code{config-file} (default: @code{#f})
15770 The configuration file to use. This is required. It will be passed to
15771 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
15772 object (@pxref{G-Expressions, file-like objects}). See @code{man
15773 dhcpd.conf} for details on the configuration file syntax.
15774 @item @code{version} (default: @code{"4"})
15775 The DHCP version to use. The ISC DHCP server supports the values ``4'',
15776 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
15777 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
15779 @item @code{run-directory} (default: @code{"/run/dhcpd"})
15780 The run directory to use. At service activation time, this directory
15781 will be created if it does not exist.
15782 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
15783 The PID file to use. This corresponds to the @code{-pf} option of
15784 @code{dhcpd}. See @code{man dhcpd} for details.
15785 @item @code{interfaces} (default: @code{'()})
15786 The names of the network interfaces on which dhcpd should listen for
15787 broadcasts. If this list is not empty, then its elements (which must be
15788 strings) will be appended to the @code{dhcpd} invocation when starting
15789 the daemon. It may not be necessary to explicitly specify any
15790 interfaces here; see @code{man dhcpd} for details.
15794 @defvr {Scheme Variable} static-networking-service-type
15795 This is the type for statically-configured network interfaces.
15796 @c TODO Document <static-networking> data structures.
15799 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
15800 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
15801 [#:requirement @code{'(udev)}]
15802 Return a service that starts @var{interface} with address @var{ip}. If
15803 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
15804 it must be a string specifying the default network gateway. @var{requirement}
15805 can be used to declare a dependency on another service before configuring the
15808 This procedure can be called several times, one for each network
15809 interface of interest. Behind the scenes what it does is extend
15810 @code{static-networking-service-type} with additional network interfaces
15816 (static-networking-service "eno1" "192.168.1.82"
15817 #:gateway "192.168.1.2"
15818 #:name-servers '("192.168.1.2"))
15825 @cindex network management
15826 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
15827 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
15828 management daemon that aims to simplify wired and wireless networking.
15830 This service adds the @var{wicd} package to the global profile, providing
15831 several commands to interact with the daemon and configure networking:
15832 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
15833 and @command{wicd-curses} user interfaces.
15836 @cindex ModemManager
15838 @defvr {Scheme Variable} modem-manager-service-type
15839 This is the service type for the
15840 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
15841 service. The value for this service type is a
15842 @code{modem-manager-configuration} record.
15844 This service is part of @code{%desktop-services} (@pxref{Desktop
15848 @deftp {Data Type} modem-manager-configuration
15849 Data type representing the configuration of ModemManager.
15852 @item @code{modem-manager} (default: @code{modem-manager})
15853 The ModemManager package to use.
15858 @cindex USB_ModeSwitch
15859 @cindex Modeswitching
15861 @defvr {Scheme Variable} usb-modeswitch-service-type
15862 This is the service type for the
15863 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch}
15864 service. The value for this service type is
15865 a @code{usb-modeswitch-configuration} record.
15867 When plugged in, some USB modems (and other USB devices) initially present
15868 themselves as a read-only storage medium and not as a modem. They need to be
15869 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
15870 installs udev rules to automatically modeswitch these devices when they are
15873 This service is part of @code{%desktop-services} (@pxref{Desktop
15877 @deftp {Data Type} usb-modeswitch-configuration
15878 Data type representing the configuration of USB_ModeSwitch.
15881 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
15882 The USB_ModeSwitch package providing the binaries for modeswitching.
15884 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
15885 The package providing the device data and udev rules file used by
15888 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
15889 Which config file to use for the USB_ModeSwitch dispatcher. By default the
15890 config file shipped with USB_ModeSwitch is used which disables logging to
15891 @file{/var/log} among other default settings. If set to @code{#f}, no config
15897 @cindex NetworkManager
15899 @defvr {Scheme Variable} network-manager-service-type
15900 This is the service type for the
15901 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
15902 service. The value for this service type is a
15903 @code{network-manager-configuration} record.
15905 This service is part of @code{%desktop-services} (@pxref{Desktop
15909 @deftp {Data Type} network-manager-configuration
15910 Data type representing the configuration of NetworkManager.
15913 @item @code{network-manager} (default: @code{network-manager})
15914 The NetworkManager package to use.
15916 @item @code{dns} (default: @code{"default"})
15917 Processing mode for DNS, which affects how NetworkManager uses the
15918 @code{resolv.conf} configuration file.
15922 NetworkManager will update @code{resolv.conf} to reflect the nameservers
15923 provided by currently active connections.
15926 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
15927 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
15928 then update @code{resolv.conf} to point to the local nameserver.
15930 With this setting, you can share your network connection. For example when
15931 you want to share your network connection to another laptop @i{via} an
15932 Ethernet cable, you can open @command{nm-connection-editor} and configure the
15933 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
15934 and reestablish the connection (or reboot).
15936 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
15937 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
15938 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
15939 browser on your host system, or connect to the VM @i{via} SSH
15940 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
15941 host-to-guest connection, run this command once:
15944 nmcli connection add type tun \
15945 connection.interface-name tap0 \
15946 tun.mode tap tun.owner $(id -u) \
15947 ipv4.method shared \
15948 ipv4.addresses 172.28.112.1/24
15951 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
15952 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
15953 @command{qemu-system-...}.
15956 NetworkManager will not modify @code{resolv.conf}.
15959 @item @code{vpn-plugins} (default: @code{'()})
15960 This is the list of available plugins for virtual private networks
15961 (VPNs). An example of this is the @code{network-manager-openvpn}
15962 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
15968 @deffn {Scheme Variable} connman-service-type
15969 This is the service type to run @url{https://01.org/connman,Connman},
15970 a network connection manager.
15972 Its value must be an
15973 @code{connman-configuration} record as in this example:
15976 (service connman-service-type
15977 (connman-configuration
15978 (disable-vpn? #t)))
15981 See below for details about @code{connman-configuration}.
15984 @deftp {Data Type} connman-configuration
15985 Data Type representing the configuration of connman.
15988 @item @code{connman} (default: @var{connman})
15989 The connman package to use.
15991 @item @code{disable-vpn?} (default: @code{#f})
15992 When true, disable connman's vpn plugin.
15996 @cindex WPA Supplicant
15997 @defvr {Scheme Variable} wpa-supplicant-service-type
15998 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
15999 supplicant}, an authentication daemon required to authenticate against
16000 encrypted WiFi or ethernet networks.
16003 @deftp {Data Type} wpa-supplicant-configuration
16004 Data type representing the configuration of WPA Supplicant.
16006 It takes the following parameters:
16009 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
16010 The WPA Supplicant package to use.
16012 @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
16013 List of services that should be started before WPA Supplicant starts.
16015 @item @code{dbus?} (default: @code{#t})
16016 Whether to listen for requests on D-Bus.
16018 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
16019 Where to store the PID file.
16021 @item @code{interface} (default: @code{#f})
16022 If this is set, it must specify the name of a network interface that
16023 WPA supplicant will control.
16025 @item @code{config-file} (default: @code{#f})
16026 Optional configuration file to use.
16028 @item @code{extra-options} (default: @code{'()})
16029 List of additional command-line arguments to pass to the daemon.
16033 @cindex hostapd service, for Wi-Fi access points
16034 @cindex Wi-Fi access points, hostapd service
16035 @defvr {Scheme Variable} hostapd-service-type
16036 This is the service type to run the @uref{https://w1.fi/hostapd/,
16037 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
16038 authentication servers. Its associated value must be a
16039 @code{hostapd-configuration} as shown below:
16042 ;; Use wlan1 to run the access point for "My Network".
16043 (service hostapd-service-type
16044 (hostapd-configuration
16045 (interface "wlan1")
16046 (ssid "My Network")
16051 @deftp {Data Type} hostapd-configuration
16052 This data type represents the configuration of the hostapd service, with
16053 the following fields:
16056 @item @code{package} (default: @code{hostapd})
16057 The hostapd package to use.
16059 @item @code{interface} (default: @code{"wlan0"})
16060 The network interface to run the WiFi access point.
16063 The SSID (@dfn{service set identifier}), a string that identifies this
16066 @item @code{broadcast-ssid?} (default: @code{#t})
16067 Whether to broadcast this SSID.
16069 @item @code{channel} (default: @code{1})
16070 The WiFi channel to use.
16072 @item @code{driver} (default: @code{"nl80211"})
16073 The driver interface type. @code{"nl80211"} is used with all Linux
16074 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
16075 RADIUS server that does # not control any wireless/wired driver.
16077 @item @code{extra-settings} (default: @code{""})
16078 Extra settings to append as-is to the hostapd configuration file. See
16079 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
16080 configuration file reference.
16084 @defvr {Scheme Variable} simulated-wifi-service-type
16085 This is the type of a service to simulate WiFi networking, which can be
16086 useful in virtual machines for testing purposes. The service loads the
16088 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
16089 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
16090 network that can be seen on @code{wlan0}, by default.
16092 The service's value is a @code{hostapd-configuration} record.
16096 @defvr {Scheme Variable} iptables-service-type
16097 This is the service type to set up an iptables configuration. iptables is a
16098 packet filtering framework supported by the Linux kernel. This service
16099 supports configuring iptables for both IPv4 and IPv6. A simple example
16100 configuration rejecting all incoming connections except those to the ssh port
16104 (service iptables-service-type
16105 (iptables-configuration
16106 (ipv4-rules (plain-file "iptables.rules" "*filter
16110 -A INPUT -p tcp --dport 22 -j ACCEPT
16111 -A INPUT -j REJECT --reject-with icmp-port-unreachable
16114 (ipv6-rules (plain-file "ip6tables.rules" "*filter
16118 -A INPUT -p tcp --dport 22 -j ACCEPT
16119 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
16125 @deftp {Data Type} iptables-configuration
16126 The data type representing the configuration of iptables.
16129 @item @code{iptables} (default: @code{iptables})
16130 The iptables package that provides @code{iptables-restore} and
16131 @code{ip6tables-restore}.
16132 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
16133 The iptables rules to use. It will be passed to @code{iptables-restore}.
16134 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
16136 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
16137 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
16138 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
16144 @defvr {Scheme Variable} nftables-service-type
16145 This is the service type to set up a nftables configuration. nftables is a
16146 netfilter project that aims to replace the existing iptables, ip6tables,
16147 arptables and ebtables framework. It provides a new packet filtering
16148 framework, a new user-space utility @command{nft}, and a compatibility layer
16149 for iptables. This service comes with a default ruleset
16150 @code{%default-nftables-ruleset} that rejecting all incomming connections
16151 except those to the ssh port 22. To use it, simply write:
16154 (service nftables-service-type)
16158 @deftp {Data Type} nftables-configuration
16159 The data type representing the configuration of nftables.
16162 @item @code{package} (default: @code{nftables})
16163 The nftables package that provides @command{nft}.
16164 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
16165 The nftables ruleset to use. This may be any ``file-like'' object
16166 (@pxref{G-Expressions, file-like objects}).
16170 @cindex NTP (Network Time Protocol), service
16171 @cindex ntpd, service for the Network Time Protocol daemon
16172 @cindex real time clock
16173 @defvr {Scheme Variable} ntp-service-type
16174 This is the type of the service running the @uref{https://www.ntp.org,
16175 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
16176 system clock synchronized with that of the specified NTP servers.
16178 The value of this service is an @code{ntpd-configuration} object, as described
16182 @deftp {Data Type} ntp-configuration
16183 This is the data type for the NTP service configuration.
16186 @item @code{servers} (default: @code{%ntp-servers})
16187 This is the list of servers (@code{<ntp-server>} records) with which
16188 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
16191 @item @code{allow-large-adjustment?} (default: @code{#t})
16192 This determines whether @command{ntpd} is allowed to make an initial
16193 adjustment of more than 1,000 seconds.
16195 @item @code{ntp} (default: @code{ntp})
16196 The NTP package to use.
16200 @defvr {Scheme Variable} %ntp-servers
16201 List of host names used as the default NTP servers. These are servers of the
16202 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
16205 @deftp {Data Type} ntp-server
16206 The data type representing the configuration of a NTP server.
16209 @item @code{type} (default: @code{'server})
16210 The type of the NTP server, given as a symbol. One of @code{'pool},
16211 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
16213 @item @code{address}
16214 The address of the server, as a string.
16216 @item @code{options}
16217 NTPD options to use with that specific server, given as a list of option names
16218 and/or of option names and values tuples. The following example define a server
16219 to use with the options @option{iburst} and @option{prefer}, as well as
16220 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
16225 (address "some.ntp.server.org")
16226 (options `(iburst (version 3) (maxpoll 16) prefer))))
16232 @deffn {Scheme Procedure} openntpd-service-type
16233 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
16234 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
16235 clock synchronized with that of the given servers.
16239 openntpd-service-type
16240 (openntpd-configuration
16241 (listen-on '("127.0.0.1" "::1"))
16242 (sensor '("udcf0 correction 70000"))
16243 (constraint-from '("www.gnu.org"))
16244 (constraints-from '("https://www.google.com/"))
16245 (allow-large-adjustment? #t)))
16250 @defvr {Scheme Variable} %openntpd-servers
16251 This variable is a list of the server addresses defined in
16252 @code{%ntp-servers}.
16255 @deftp {Data Type} openntpd-configuration
16257 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
16258 The openntpd executable to use.
16259 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
16260 A list of local IP addresses or hostnames the ntpd daemon should listen on.
16261 @item @code{query-from} (default: @code{'()})
16262 A list of local IP address the ntpd daemon should use for outgoing queries.
16263 @item @code{sensor} (default: @code{'()})
16264 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
16265 will listen to each sensor that actually exists and ignore non-existent ones.
16266 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
16268 @item @code{server} (default: @code{'()})
16269 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
16270 @item @code{servers} (default: @code{%openntp-servers})
16271 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
16272 @item @code{constraint-from} (default: @code{'()})
16273 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
16274 This time information is not used for precision but acts as an authenticated
16275 constraint, thereby reducing the impact of unauthenticated NTP
16276 man-in-the-middle attacks.
16277 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
16279 @item @code{constraints-from} (default: @code{'()})
16280 As with constraint from, specify a list of URLs, IP addresses or hostnames of
16281 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
16282 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
16283 @item @code{allow-large-adjustment?} (default: @code{#f})
16284 Determines if @code{ntpd} is allowed to make an initial adjustment of more
16290 @deffn {Scheme variable} inetd-service-type
16291 This service runs the @command{inetd} (@pxref{inetd invocation,,,
16292 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
16293 connections on internet sockets, and lazily starts the specified server
16294 program when a connection is made on one of these sockets.
16296 The value of this service is an @code{inetd-configuration} object. The
16297 following example configures the @command{inetd} daemon to provide the
16298 built-in @command{echo} service, as well as an smtp service which
16299 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
16300 gateway @code{hostname}:
16305 (inetd-configuration
16309 (socket-type 'stream)
16316 (socket-type 'stream)
16320 (program (file-append openssh "/bin/ssh"))
16322 '("ssh" "-qT" "-i" "/path/to/ssh_key"
16323 "-W" "smtp-server:25" "user@@hostname")))))))
16326 See below for more details about @code{inetd-configuration}.
16329 @deftp {Data Type} inetd-configuration
16330 Data type representing the configuration of @command{inetd}.
16333 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
16334 The @command{inetd} executable to use.
16336 @item @code{entries} (default: @code{'()})
16337 A list of @command{inetd} service entries. Each entry should be created
16338 by the @code{inetd-entry} constructor.
16342 @deftp {Data Type} inetd-entry
16343 Data type representing an entry in the @command{inetd} configuration.
16344 Each entry corresponds to a socket where @command{inetd} will listen for
16348 @item @code{node} (default: @code{#f})
16349 Optional string, a comma-separated list of local addresses
16350 @command{inetd} should use when listening for this service.
16351 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
16352 description of all options.
16354 A string, the name must correspond to an entry in @code{/etc/services}.
16355 @item @code{socket-type}
16356 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
16358 @item @code{protocol}
16359 A string, must correspond to an entry in @code{/etc/protocols}.
16360 @item @code{wait?} (default: @code{#t})
16361 Whether @command{inetd} should wait for the server to exit before
16362 listening to new service requests.
16364 A string containing the user (and, optionally, group) name of the user
16365 as whom the server should run. The group name can be specified in a
16366 suffix, separated by a colon or period, i.e.@: @code{"user"},
16367 @code{"user:group"} or @code{"user.group"}.
16368 @item @code{program} (default: @code{"internal"})
16369 The server program which will serve the requests, or @code{"internal"}
16370 if @command{inetd} should use a built-in service.
16371 @item @code{arguments} (default: @code{'()})
16372 A list strings or file-like objects, which are the server program's
16373 arguments, starting with the zeroth argument, i.e.@: the name of the
16374 program itself. For @command{inetd}'s internal services, this entry
16375 must be @code{'()} or @code{'("internal")}.
16378 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
16379 detailed discussion of each configuration field.
16383 @defvr {Scheme Variable} tor-service-type
16384 This is the type for a service that runs the @uref{https://torproject.org,
16385 Tor} anonymous networking daemon. The service is configured using a
16386 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
16387 @code{tor} unprivileged user, which is a member of the @code{tor} group.
16391 @deftp {Data Type} tor-configuration
16393 @item @code{tor} (default: @code{tor})
16394 The package that provides the Tor daemon. This package is expected to provide
16395 the daemon at @file{bin/tor} relative to its output directory. The default
16396 package is the @uref{https://www.torproject.org, Tor Project's}
16399 @item @code{config-file} (default: @code{(plain-file "empty" "")})
16400 The configuration file to use. It will be appended to a default configuration
16401 file, and the final configuration file will be passed to @code{tor} via its
16402 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
16403 file-like objects}). See @code{man tor} for details on the configuration file
16406 @item @code{hidden-services} (default: @code{'()})
16407 The list of @code{<hidden-service>} records to use. For any hidden service
16408 you include in this list, appropriate configuration to enable the hidden
16409 service will be automatically added to the default configuration file. You
16410 may conveniently create @code{<hidden-service>} records using the
16411 @code{tor-hidden-service} procedure described below.
16413 @item @code{socks-socket-type} (default: @code{'tcp})
16414 The default socket type that Tor should use for its SOCKS socket. This must
16415 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
16416 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
16417 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
16418 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
16421 If you want to customize the SOCKS socket in more detail, leave
16422 @code{socks-socket-type} at its default value of @code{'tcp} and use
16423 @code{config-file} to override the default by providing your own
16424 @code{SocksPort} option.
16428 @cindex hidden service
16429 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
16430 Define a new Tor @dfn{hidden service} called @var{name} and implementing
16431 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
16434 '((22 "127.0.0.1:22")
16435 (80 "127.0.0.1:8080"))
16438 In this example, port 22 of the hidden service is mapped to local port 22, and
16439 port 80 is mapped to local port 8080.
16441 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
16442 the @file{hostname} file contains the @code{.onion} host name for the hidden
16445 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
16446 project's documentation} for more information.
16449 The @code{(gnu services rsync)} module provides the following services:
16451 You might want an rsync daemon if you have files that you want available
16452 so anyone (or just yourself) can download existing files or upload new
16455 @deffn {Scheme Variable} rsync-service-type
16456 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
16457 The value for this service type is a
16458 @command{rsync-configuration} record as in this example:
16461 (service rsync-service-type)
16464 See below for details about @code{rsync-configuration}.
16467 @deftp {Data Type} rsync-configuration
16468 Data type representing the configuration for @code{rsync-service}.
16471 @item @code{package} (default: @var{rsync})
16472 @code{rsync} package to use.
16474 @item @code{port-number} (default: @code{873})
16475 TCP port on which @command{rsync} listens for incoming connections. If port
16476 is less than @code{1024} @command{rsync} needs to be started as the
16477 @code{root} user and group.
16479 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
16480 Name of the file where @command{rsync} writes its PID.
16482 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
16483 Name of the file where @command{rsync} writes its lock file.
16485 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
16486 Name of the file where @command{rsync} writes its log file.
16488 @item @code{use-chroot?} (default: @var{#t})
16489 Whether to use chroot for @command{rsync} shared directory.
16491 @item @code{share-path} (default: @file{/srv/rsync})
16492 Location of the @command{rsync} shared directory.
16494 @item @code{share-comment} (default: @code{"Rsync share"})
16495 Comment of the @command{rsync} shared directory.
16497 @item @code{read-only?} (default: @var{#f})
16498 Read-write permissions to shared directory.
16500 @item @code{timeout} (default: @code{300})
16501 I/O timeout in seconds.
16503 @item @code{user} (default: @var{"root"})
16504 Owner of the @code{rsync} process.
16506 @item @code{group} (default: @var{"root"})
16507 Group of the @code{rsync} process.
16509 @item @code{uid} (default: @var{"rsyncd"})
16510 User name or user ID that file transfers to and from that module should take
16511 place as when the daemon was run as @code{root}.
16513 @item @code{gid} (default: @var{"rsyncd"})
16514 Group name or group ID that will be used when accessing the module.
16519 The @code{(gnu services syncthing)} module provides the following services:
16522 You might want a syncthing daemon if you have files between two or more
16523 computers and want to sync them in real time, safely protected from
16526 @deffn {Scheme Variable} syncthing-service-type
16527 This is the service type for the @uref{https://syncthing.net/,
16528 syncthing} daemon, The value for this service type is a
16529 @command{syncthing-configuration} record as in this example:
16532 (service syncthing-service-type
16533 (syncthing-configuration (user "alice")))
16536 See below for details about @code{syncthing-configuration}.
16538 @deftp {Data Type} syncthing-configuration
16539 Data type representing the configuration for @code{syncthing-service-type}.
16542 @item @code{syncthing} (default: @var{syncthing})
16543 @code{syncthing} package to use.
16545 @item @code{arguments} (default: @var{'()})
16546 List of command-line arguments passing to @code{syncthing} binary.
16548 @item @code{logflags} (default: @var{0})
16549 Sum of loging flags, see
16550 @uref{https://docs.syncthing.net/users/syncthing.html#cmdoption-logflags, Syncthing documentation logflags}.
16552 @item @code{user} (default: @var{#f})
16553 The user as which the Syncthing service is to be run.
16554 This assumes that the specified user exists.
16556 @item @code{group} (default: @var{"users"})
16557 The group as which the Syncthing service is to be run.
16558 This assumes that the specified group exists.
16560 @item @code{home} (default: @var{#f})
16561 Common configuration and data directory. The default configuration
16562 directory is @file{$HOME} of the specified Syncthing @code{user}.
16568 Furthermore, @code{(gnu services ssh)} provides the following services.
16572 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
16573 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
16574 [#:allow-empty-passwords? #f] [#:root-login? #f] @
16575 [#:syslog-output? #t] [#:x11-forwarding? #t] @
16576 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
16577 [#:public-key-authentication? #t] [#:initialize? #t]
16578 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
16579 @var{host-key} must designate a file containing the host key, and readable
16582 When @var{daemonic?} is true, @command{lshd} will detach from the
16583 controlling terminal and log its output to syslogd, unless one sets
16584 @var{syslog-output?} to false. Obviously, it also makes lsh-service
16585 depend on existence of syslogd service. When @var{pid-file?} is true,
16586 @command{lshd} writes its PID to the file called @var{pid-file}.
16588 When @var{initialize?} is true, automatically create the seed and host key
16589 upon service activation if they do not exist yet. This may take long and
16590 require interaction.
16592 When @var{initialize?} is false, it is up to the user to initialize the
16593 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
16594 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
16595 basics,,, lsh, LSH Manual}).
16597 When @var{interfaces} is empty, lshd listens for connections on all the
16598 network interfaces; otherwise, @var{interfaces} must be a list of host names
16601 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
16602 passwords, and @var{root-login?} specifies whether to accept log-ins as
16605 The other options should be self-descriptive.
16610 @deffn {Scheme Variable} openssh-service-type
16611 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
16612 shell daemon, @command{sshd}. Its value must be an
16613 @code{openssh-configuration} record as in this example:
16616 (service openssh-service-type
16617 (openssh-configuration
16618 (x11-forwarding? #t)
16619 (permit-root-login 'without-password)
16621 `(("alice" ,(local-file "alice.pub"))
16622 ("bob" ,(local-file "bob.pub"))))))
16625 See below for details about @code{openssh-configuration}.
16627 This service can be extended with extra authorized keys, as in this
16631 (service-extension openssh-service-type
16632 (const `(("charlie"
16633 ,(local-file "charlie.pub")))))
16637 @deftp {Data Type} openssh-configuration
16638 This is the configuration record for OpenSSH's @command{sshd}.
16641 @item @code{openssh} (default @var{openssh})
16642 The Openssh package to use.
16644 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
16645 Name of the file where @command{sshd} writes its PID.
16647 @item @code{port-number} (default: @code{22})
16648 TCP port on which @command{sshd} listens for incoming connections.
16650 @item @code{permit-root-login} (default: @code{#f})
16651 This field determines whether and when to allow logins as root. If
16652 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
16653 If it's the symbol @code{'without-password}, then root logins are
16654 permitted but not with password-based authentication.
16656 @item @code{allow-empty-passwords?} (default: @code{#f})
16657 When true, users with empty passwords may log in. When false, they may
16660 @item @code{password-authentication?} (default: @code{#t})
16661 When true, users may log in with their password. When false, they have
16662 other authentication methods.
16664 @item @code{public-key-authentication?} (default: @code{#t})
16665 When true, users may log in using public key authentication. When
16666 false, users have to use other authentication method.
16668 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
16669 This is used only by protocol version 2.
16671 @item @code{x11-forwarding?} (default: @code{#f})
16672 When true, forwarding of X11 graphical client connections is
16673 enabled---in other words, @command{ssh} options @option{-X} and
16674 @option{-Y} will work.
16676 @item @code{allow-agent-forwarding?} (default: @code{#t})
16677 Whether to allow agent forwarding.
16679 @item @code{allow-tcp-forwarding?} (default: @code{#t})
16680 Whether to allow TCP forwarding.
16682 @item @code{gateway-ports?} (default: @code{#f})
16683 Whether to allow gateway ports.
16685 @item @code{challenge-response-authentication?} (default: @code{#f})
16686 Specifies whether challenge response authentication is allowed (e.g.@: via
16689 @item @code{use-pam?} (default: @code{#t})
16690 Enables the Pluggable Authentication Module interface. If set to
16691 @code{#t}, this will enable PAM authentication using
16692 @code{challenge-response-authentication?} and
16693 @code{password-authentication?}, in addition to PAM account and session
16694 module processing for all authentication types.
16696 Because PAM challenge response authentication usually serves an
16697 equivalent role to password authentication, you should disable either
16698 @code{challenge-response-authentication?} or
16699 @code{password-authentication?}.
16701 @item @code{print-last-log?} (default: @code{#t})
16702 Specifies whether @command{sshd} should print the date and time of the
16703 last user login when a user logs in interactively.
16705 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
16706 Configures external subsystems (e.g.@: file transfer daemon).
16708 This is a list of two-element lists, each of which containing the
16709 subsystem name and a command (with optional arguments) to execute upon
16712 The command @command{internal-sftp} implements an in-process SFTP
16713 server. Alternatively, one can specify the @command{sftp-server} command:
16715 (service openssh-service-type
16716 (openssh-configuration
16718 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
16721 @item @code{accepted-environment} (default: @code{'()})
16722 List of strings describing which environment variables may be exported.
16724 Each string gets on its own line. See the @code{AcceptEnv} option in
16725 @code{man sshd_config}.
16727 This example allows ssh-clients to export the @env{COLORTERM} variable.
16728 It is set by terminal emulators, which support colors. You can use it in
16729 your shell's resource file to enable colors for the prompt and commands
16730 if this variable is set.
16733 (service openssh-service-type
16734 (openssh-configuration
16735 (accepted-environment '("COLORTERM"))))
16738 @item @code{authorized-keys} (default: @code{'()})
16739 @cindex authorized keys, SSH
16740 @cindex SSH authorized keys
16741 This is the list of authorized keys. Each element of the list is a user
16742 name followed by one or more file-like objects that represent SSH public
16746 (openssh-configuration
16748 `(("rekado" ,(local-file "rekado.pub"))
16749 ("chris" ,(local-file "chris.pub"))
16750 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
16754 registers the specified public keys for user accounts @code{rekado},
16755 @code{chris}, and @code{root}.
16757 Additional authorized keys can be specified @i{via}
16758 @code{service-extension}.
16760 Note that this does @emph{not} interfere with the use of
16761 @file{~/.ssh/authorized_keys}.
16763 @item @code{log-level} (default: @code{'info})
16764 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
16765 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
16766 page for @file{sshd_config} for the full list of level names.
16768 @item @code{extra-content} (default: @code{""})
16769 This field can be used to append arbitrary text to the configuration file. It
16770 is especially useful for elaborate configurations that cannot be expressed
16771 otherwise. This configuration, for example, would generally disable root
16772 logins, but permit them from one specific IP address:
16775 (openssh-configuration
16777 Match Address 192.168.0.1
16778 PermitRootLogin yes"))
16784 @deffn {Scheme Procedure} dropbear-service [@var{config}]
16785 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
16786 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
16789 For example, to specify a Dropbear service listening on port 1234, add
16790 this call to the operating system's @code{services} field:
16793 (dropbear-service (dropbear-configuration
16794 (port-number 1234)))
16798 @deftp {Data Type} dropbear-configuration
16799 This data type represents the configuration of a Dropbear SSH daemon.
16802 @item @code{dropbear} (default: @var{dropbear})
16803 The Dropbear package to use.
16805 @item @code{port-number} (default: 22)
16806 The TCP port where the daemon waits for incoming connections.
16808 @item @code{syslog-output?} (default: @code{#t})
16809 Whether to enable syslog output.
16811 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
16812 File name of the daemon's PID file.
16814 @item @code{root-login?} (default: @code{#f})
16815 Whether to allow @code{root} logins.
16817 @item @code{allow-empty-passwords?} (default: @code{#f})
16818 Whether to allow empty passwords.
16820 @item @code{password-authentication?} (default: @code{#t})
16821 Whether to enable password-based authentication.
16826 @deffn {Scheme Variable} autossh-service-type
16827 This is the type for the @uref{https://www.harding.motd.ca/autossh,
16828 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
16829 restarting it as necessary should it die or stop passing traffic.
16830 AutoSSH can be run manually from the command-line by passing arguments
16831 to the binary @command{autossh} from the package @code{autossh}, but it
16832 can also be run as a Guix service. This latter use case is documented
16835 AutoSSH can be used to forward local traffic to a remote machine using
16836 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
16839 For example, to specify a service running autossh as the user
16840 @code{pino} and forwarding all local connections to port @code{8081} to
16841 @code{remote:8081} using an SSH tunnel, add this call to the operating
16842 system's @code{services} field:
16845 (service autossh-service-type
16846 (autossh-configuration
16848 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
16852 @deftp {Data Type} autossh-configuration
16853 This data type represents the configuration of an AutoSSH service.
16857 @item @code{user} (default @code{"autossh"})
16858 The user as which the AutoSSH service is to be run.
16859 This assumes that the specified user exists.
16861 @item @code{poll} (default @code{600})
16862 Specifies the connection poll time in seconds.
16864 @item @code{first-poll} (default @code{#f})
16865 Specifies how many seconds AutoSSH waits before the first connection
16866 test. After this first test, polling is resumed at the pace defined in
16867 @code{poll}. When set to @code{#f}, the first poll is not treated
16868 specially and will also use the connection poll specified in
16871 @item @code{gate-time} (default @code{30})
16872 Specifies how many seconds an SSH connection must be active before it is
16873 considered successful.
16875 @item @code{log-level} (default @code{1})
16876 The log level, corresponding to the levels used by syslog---so @code{0}
16877 is the most silent while @code{7} is the chattiest.
16879 @item @code{max-start} (default @code{#f})
16880 The maximum number of times SSH may be (re)started before AutoSSH exits.
16881 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
16883 @item @code{message} (default @code{""})
16884 The message to append to the echo message sent when testing connections.
16886 @item @code{port} (default @code{"0"})
16887 The ports used for monitoring the connection. When set to @code{"0"},
16888 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
16889 a positive integer, ports @var{n} and @var{n}+1 are used for
16890 monitoring the connection, such that port @var{n} is the base
16891 monitoring port and @code{n+1} is the echo port. When set to
16892 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
16893 integers, the ports @var{n} and @var{m} are used for monitoring the
16894 connection, such that port @var{n} is the base monitoring port and
16895 @var{m} is the echo port.
16897 @item @code{ssh-options} (default @code{'()})
16898 The list of command-line arguments to pass to @command{ssh} when it is
16899 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
16900 may cause undefined behaviour.
16906 @deffn {Scheme Variable} webssh-service-type
16907 This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
16908 program that runs a web SSH client. WebSSH can be run manually from the
16909 command-line by passing arguments to the binary @command{wssh} from the
16910 package @code{webssh}, but it can also be run as a Guix service. This
16911 latter use case is documented here.
16913 For example, to specify a service running WebSSH on loopback interface
16914 on port @code{8888} with reject policy with a list of allowed to
16915 connection hosts, and NGINX as a reverse-proxy to this service listening
16916 for HTTPS connection, add this call to the operating system's
16917 @code{services} field:
16920 (service webssh-service-type
16921 (webssh-configuration (address "127.0.0.1")
16924 (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
16925 "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
16927 (service nginx-service-type
16928 (nginx-configuration
16931 (nginx-server-configuration
16932 (inherit %webssh-configuration-nginx)
16933 (server-name '("webssh.example.com"))
16934 (listen '("443 ssl"))
16935 (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
16936 (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
16938 (cons (nginx-location-configuration
16939 (uri "/.well-known")
16940 (body '("root /var/www;")))
16941 (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
16945 @deftp {Data Type} webssh-configuration
16946 Data type representing the configuration for @code{webssh-service}.
16949 @item @code{package} (default: @var{webssh})
16950 @code{webssh} package to use.
16952 @item @code{user-name} (default: @var{"webssh"})
16953 User name or user ID that file transfers to and from that module should take
16956 @item @code{group-name} (default: @var{"webssh"})
16957 Group name or group ID that will be used when accessing the module.
16959 @item @code{address} (default: @var{#f})
16960 IP address on which @command{webssh} listens for incoming connections.
16962 @item @code{port} (default: @var{8888})
16963 TCP port on which @command{webssh} listens for incoming connections.
16965 @item @code{policy} (default: @var{#f})
16966 Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
16968 @item @code{known-hosts} (default: @var{'()})
16969 List of hosts which allowed for SSH connection from @command{webssh}.
16971 @item @code{log-file} (default: @file{"/var/log/webssh.log"})
16972 Name of the file where @command{webssh} writes its log file.
16974 @item @code{log-level} (default: @var{#f})
16980 @defvr {Scheme Variable} %facebook-host-aliases
16981 This variable contains a string for use in @file{/etc/hosts}
16982 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
16983 line contains a entry that maps a known server name of the Facebook
16984 on-line service---e.g., @code{www.facebook.com}---to the local
16985 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
16987 This variable is typically used in the @code{hosts-file} field of an
16988 @code{operating-system} declaration (@pxref{operating-system Reference,
16989 @file{/etc/hosts}}):
16992 (use-modules (gnu) (guix))
16995 (host-name "mymachine")
16998 ;; Create a /etc/hosts file with aliases for "localhost"
16999 ;; and "mymachine", as well as for Facebook servers.
17000 (plain-file "hosts"
17001 (string-append (local-host-aliases host-name)
17002 %facebook-host-aliases))))
17005 This mechanism can prevent programs running locally, such as Web
17006 browsers, from accessing Facebook.
17009 The @code{(gnu services avahi)} provides the following definition.
17011 @defvr {Scheme Variable} avahi-service-type
17012 This is the service that runs @command{avahi-daemon}, a system-wide
17013 mDNS/DNS-SD responder that allows for service discovery and
17014 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
17015 Its value must be an @code{avahi-configuration} record---see below.
17017 This service extends the name service cache daemon (nscd) so that it can
17018 resolve @code{.local} host names using
17019 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
17020 Service Switch}, for information on host name resolution.
17022 Additionally, add the @var{avahi} package to the system profile so that
17023 commands such as @command{avahi-browse} are directly usable.
17026 @deftp {Data Type} avahi-configuration
17027 Data type representation the configuration for Avahi.
17031 @item @code{host-name} (default: @code{#f})
17032 If different from @code{#f}, use that as the host name to
17033 publish for this machine; otherwise, use the machine's actual host name.
17035 @item @code{publish?} (default: @code{#t})
17036 When true, allow host names and services to be published (broadcast) over the
17039 @item @code{publish-workstation?} (default: @code{#t})
17040 When true, @command{avahi-daemon} publishes the machine's host name and IP
17041 address via mDNS on the local network. To view the host names published on
17042 your local network, you can run:
17045 avahi-browse _workstation._tcp
17048 @item @code{wide-area?} (default: @code{#f})
17049 When true, DNS-SD over unicast DNS is enabled.
17051 @item @code{ipv4?} (default: @code{#t})
17052 @itemx @code{ipv6?} (default: @code{#t})
17053 These fields determine whether to use IPv4/IPv6 sockets.
17055 @item @code{domains-to-browse} (default: @code{'()})
17056 This is a list of domains to browse.
17060 @deffn {Scheme Variable} openvswitch-service-type
17061 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
17062 service, whose value should be an @code{openvswitch-configuration}
17066 @deftp {Data Type} openvswitch-configuration
17067 Data type representing the configuration of Open vSwitch, a multilayer
17068 virtual switch which is designed to enable massive network automation
17069 through programmatic extension.
17072 @item @code{package} (default: @var{openvswitch})
17073 Package object of the Open vSwitch.
17078 @defvr {Scheme Variable} pagekite-service-type
17079 This is the service type for the @uref{https://pagekite.net, PageKite} service,
17080 a tunneling solution for making localhost servers publicly visible, even from
17081 behind restrictive firewalls or NAT without forwarded ports. The value for
17082 this service type is a @code{pagekite-configuration} record.
17084 Here's an example exposing the local HTTP and SSH daemons:
17087 (service pagekite-service-type
17088 (pagekite-configuration
17089 (kites '("http:@@kitename:localhost:80:@@kitesecret"
17090 "raw/22:@@kitename:localhost:22:@@kitesecret"))
17091 (extra-file "/etc/pagekite.rc")))
17095 @deftp {Data Type} pagekite-configuration
17096 Data type representing the configuration of PageKite.
17099 @item @code{package} (default: @var{pagekite})
17100 Package object of PageKite.
17102 @item @code{kitename} (default: @code{#f})
17103 PageKite name for authenticating to the frontend server.
17105 @item @code{kitesecret} (default: @code{#f})
17106 Shared secret for authenticating to the frontend server. You should probably
17107 put this inside @code{extra-file} instead.
17109 @item @code{frontend} (default: @code{#f})
17110 Connect to the named PageKite frontend server instead of the
17111 @uref{https://pagekite.net,,pagekite.net} service.
17113 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
17114 List of service kites to use. Exposes HTTP on port 80 by default. The format
17115 is @code{proto:kitename:host:port:secret}.
17117 @item @code{extra-file} (default: @code{#f})
17118 Extra configuration file to read, which you are expected to create manually.
17119 Use this to add additional options and manage shared secrets out-of-band.
17124 @defvr {Scheme Variable} yggdrasil-service-type
17125 The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
17126 Yggdrasil network}, an early-stage implementation of a fully end-to-end
17127 encrypted IPv6 network.
17130 Yggdrasil provides name-independent routing with cryptographically generated
17131 addresses. Static addressing means you can keep the same address as long as
17132 you want, even if you move to a new location, or generate a new address (by
17133 generating new keys) whenever you want.
17134 @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
17137 Pass it a value of @code{yggdrasil-configuration} to connect it to public
17138 peers and/or local peers.
17140 Here is an example using public peers and a static address. The static
17141 signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
17142 (the default value for @code{config-file}).
17145 ;; part of the operating-system declaration
17146 (service yggdrasil-service-type
17147 (yggdrasil-configuration
17148 (autoconf? #f) ;; use only the public peers
17151 ;; https://github.com/yggdrasil-network/public-peers
17152 '((peers . #("tcp://1.2.3.4:1337"))))
17153 ;; /etc/yggdrasil-private.conf is the default value for config-file
17157 # sample content for /etc/yggdrasil-private.conf
17159 # Your public encryption key. Your peers may ask you for this to put
17160 # into their AllowedEncryptionPublicKeys configuration.
17161 EncryptionPublicKey: 378dc5...
17163 # Your private encryption key. DO NOT share this with anyone!
17164 EncryptionPrivateKey: 0777...
17166 # Your public signing key. You should not ordinarily need to share
17167 # this with anyone.
17168 SigningPublicKey: e1664...
17170 # Your private signing key. DO NOT share this with anyone!
17171 SigningPrivateKey: 0589d...
17176 @deftp {Data Type} yggdrasil-configuration
17177 Data type representing the configuration of Yggdrasil.
17180 @item @code{package} (default: @code{yggdrasil})
17181 Package object of Yggdrasil.
17183 @item @code{json-config} (default: @code{'()})
17184 Contents of @file{/etc/yggdrasil.conf}. Will be merged with
17185 @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
17186 the Guix store, which is readable to all users. @strong{Do not store your
17187 private keys in it}. See the output of @code{yggdrasil -genconf} for a
17188 quick overview of valid keys and their default values.
17190 @item @code{autoconf?} (default: @code{#f})
17191 Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
17192 and peer with IPv6 neighbors.
17194 @item @code{log-level} (default: @code{'info})
17195 How much detail to include in logs. Use @code{'debug} for more detail.
17197 @item @code{log-to} (default: @code{'stdout})
17198 Where to send logs. By default, the service logs standard output to
17199 @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
17200 sends output to the running syslog service.
17202 @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
17203 What HJSON file to load sensitive data from. This is where private keys
17204 should be stored, which are necessary to specify if you don't want a
17205 randomized address after each restart. Use @code{#f} to disable. Options
17206 defined in this file take precedence over @code{json-config}. Use the output
17207 of @code{yggdrasil -genconf} as a starting point. To configure a static
17208 address, delete everything except these options:
17211 @item @code{EncryptionPublicKey}
17212 @item @code{EncryptionPrivateKey}
17213 @item @code{SigningPublicKey}
17214 @item @code{SigningPrivateKey}
17220 @deffn {Scheme Variable} keepalived-service-type
17221 This is the type for the @uref{https://www.keepalived.org/, Keepalived}
17222 routing software, @command{keepalived}. Its value must be an
17223 @code{keepalived-configuration} record as in this example for master
17227 (service keepalived-service-type
17228 (keepalived-configuration
17229 (config-file (local-file "keepalived-master.conf"))))
17232 where @file{keepalived-master.conf}:
17235 vrrp_instance my-group @{
17238 virtual_router_id 100
17240 unicast_peer @{ 10.0.0.2 @}
17241 virtual_ipaddress @{
17247 and for backup machine:
17250 (service keepalived-service-type
17251 (keepalived-configuration
17252 (config-file (local-file "keepalived-backup.conf"))))
17255 where @file{keepalived-backup.conf}:
17258 vrrp_instance my-group @{
17261 virtual_router_id 100
17263 unicast_peer @{ 10.0.0.3 @}
17264 virtual_ipaddress @{
17271 @node Unattended Upgrades
17272 @subsection Unattended Upgrades
17274 @cindex unattended upgrades
17275 @cindex upgrades, unattended
17276 Guix provides a service to perform @emph{unattended upgrades}:
17277 periodically, the system automatically reconfigures itself from the
17278 latest Guix. Guix System has several properties that make unattended
17283 upgrades are transactional (either the upgrade succeeds or it fails, but
17284 you cannot end up with an ``in-between'' system state);
17286 the upgrade log is kept---you can view it with @command{guix system
17287 list-generations}---and you can roll back to any previous generation,
17288 should the upgraded system fail to behave as intended;
17290 channel code is authenticated so you know you can only run genuine code
17291 (@pxref{Channels});
17293 @command{guix system reconfigure} prevents downgrades, which makes it
17294 immune to @dfn{downgrade attacks}.
17297 To set up unattended upgrades, add an instance of
17298 @code{unattended-upgrade-service-type} like the one below to the list of
17299 your operating system services:
17302 (service unattended-upgrade-service-type)
17305 The defaults above set up weekly upgrades: every Sunday at midnight.
17306 You do not need to provide the operating system configuration file: it
17307 uses @file{/run/current-system/configuration.scm}, which ensures it
17308 always uses your latest configuration---@pxref{provenance-service-type},
17309 for more information about this file.
17311 There are several things that can be configured, in particular the
17312 periodicity and services (daemons) to be restarted upon completion.
17313 When the upgrade is successful, the service takes care of deleting
17314 system generations older that some threshold, as per @command{guix
17315 system delete-generations}. See the reference below for details.
17317 To ensure that upgrades are actually happening, you can run
17318 @command{guix system describe}. To investigate upgrade failures, visit
17319 the unattended upgrade log file (see below).
17321 @defvr {Scheme Variable} unattended-upgrade-service-type
17322 This is the service type for unattended upgrades. It sets up an mcron
17323 job (@pxref{Scheduled Job Execution}) that runs @command{guix system
17324 reconfigure} from the latest version of the specified channels.
17326 Its value must be a @code{unattended-upgrade-configuration} record (see
17330 @deftp {Data Type} unattended-upgrade-configuration
17331 This data type represents the configuration of the unattended upgrade
17332 service. The following fields are available:
17335 @item @code{schedule} (default: @code{"30 01 * * 0"})
17336 This is the schedule of upgrades, expressed as a gexp containing an
17337 mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
17338 mcron, GNU@tie{}mcron}).
17340 @item @code{channels} (default: @code{#~%default-channels})
17341 This gexp specifies the channels to use for the upgrade
17342 (@pxref{Channels}). By default, the tip of the official @code{guix}
17345 @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
17346 This field specifies the operating system configuration file to use.
17347 The default is to reuse the config file of the current configuration.
17349 There are cases, though, where referring to
17350 @file{/run/current-system/configuration.scm} is not enough, for instance
17351 because that file refers to extra files (SSH public keys, extra
17352 configuration files, etc.) @i{via} @code{local-file} and similar
17353 constructs. For those cases, we recommend something along these lines:
17356 (unattended-upgrade-configuration
17357 (operating-system-file
17358 (file-append (local-file "." "config-dir" #:recursive? #t)
17362 The effect here is to import all of the current directory into the
17363 store, and to refer to @file{config.scm} within that directory.
17364 Therefore, uses of @code{local-file} within @file{config.scm} will work
17365 as expected. @xref{G-Expressions}, for information about
17366 @code{local-file} and @code{file-append}.
17368 @item @code{services-to-restart} (default: @code{'(mcron)})
17369 This field specifies the Shepherd services to restart when the upgrade
17372 Those services are restarted right away upon completion, as with
17373 @command{herd restart}, which ensures that the latest version is
17374 running---remember that by default @command{guix system reconfigure}
17375 only restarts services that are not currently running, which is
17376 conservative: it minimizes disruption but leaves outdated services
17379 Use @command{herd status} to find out candidates for restarting.
17380 @xref{Services}, for general information about services. Common
17381 services to restart would include @code{ntpd} and @code{ssh-daemon}.
17383 By default, the @code{mcron} service is restarted. This ensures that
17384 the latest version of the unattended upgrade job will be used next time.
17386 @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
17387 This is the expiration time in seconds for system generations. System
17388 generations older that this amount of time are deleted with
17389 @command{guix system delete-generations} when an upgrade completes.
17392 The unattended upgrade service does not run the garbage collector. You
17393 will probably want to set up your own mcron job to run @command{guix gc}
17397 @item @code{maximum-duration} (default: @code{3600})
17398 Maximum duration in seconds for the upgrade; past that time, the upgrade
17401 This is primarily useful to ensure the upgrade does not end up
17402 rebuilding or re-downloading ``the world''.
17404 @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
17405 File where unattended upgrades are logged.
17410 @subsection X Window
17413 @cindex X Window System
17414 @cindex login manager
17415 Support for the X Window graphical display system---specifically
17416 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
17417 there is no @code{xorg-service} procedure. Instead, the X server is
17418 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
17421 @cindex GNOME, login manager
17422 GDM of course allows users to log in into window managers and desktop
17423 environments other than GNOME; for those using GNOME, GDM is required for
17424 features such as automatic screen locking.
17426 @cindex window manager
17427 To use X11, you must install at least one @dfn{window manager}---for
17428 example the @code{windowmaker} or @code{openbox} packages---preferably
17429 by adding it to the @code{packages} field of your operating system
17430 definition (@pxref{operating-system Reference, system-wide packages}).
17432 @defvr {Scheme Variable} gdm-service-type
17433 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
17434 Desktop Manager} (GDM), a program that manages graphical display servers and
17435 handles graphical user logins. Its value must be a @code{gdm-configuration}
17438 @cindex session types (X11)
17439 @cindex X11 session types
17440 GDM looks for @dfn{session types} described by the @file{.desktop} files in
17441 @file{/run/current-system/profile/share/xsessions} and allows users to choose
17442 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
17443 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
17444 set of packages automatically makes them available at the log-in screen.
17446 In addition, @file{~/.xsession} files are honored. When available,
17447 @file{~/.xsession} must be an executable that starts a window manager
17448 and/or other X clients.
17451 @deftp {Data Type} gdm-configuration
17453 @item @code{auto-login?} (default: @code{#f})
17454 @itemx @code{default-user} (default: @code{#f})
17455 When @code{auto-login?} is false, GDM presents a log-in screen.
17457 When @code{auto-login?} is true, GDM logs in directly as
17458 @code{default-user}.
17460 @item @code{debug?} (default: @code{#f})
17461 When true, GDM writes debug messages to its log.
17463 @item @code{gnome-shell-assets} (default: ...)
17464 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
17466 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
17467 Configuration of the Xorg graphical server.
17469 @item @code{xsession} (default: @code{(xinitrc)})
17470 Script to run before starting a X session.
17472 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
17473 File name of the @code{dbus-daemon} executable.
17475 @item @code{gdm} (default: @code{gdm})
17476 The GDM package to use.
17480 @defvr {Scheme Variable} slim-service-type
17481 This is the type for the SLiM graphical login manager for X11.
17483 Like GDM, SLiM looks for session types described by @file{.desktop} files and
17484 allows users to choose a session from the log-in screen using @kbd{F1}. It
17485 also honors @file{~/.xsession} files.
17487 Unlike GDM, SLiM does not spawn the user session on a different VT after
17488 logging in, which means that you can only start one graphical session. If you
17489 want to be able to run multiple graphical sessions at the same time you have
17490 to add multiple SLiM services to your system services. The following example
17491 shows how to replace the default GDM service with two SLiM services on tty7
17495 (use-modules (gnu services)
17496 (gnu services desktop)
17497 (gnu services xorg)
17498 (srfi srfi-1)) ;for 'remove'
17502 (services (cons* (service slim-service-type (slim-configuration
17505 (service slim-service-type (slim-configuration
17508 (remove (lambda (service)
17509 (eq? (service-kind service) gdm-service-type))
17510 %desktop-services))))
17515 @deftp {Data Type} slim-configuration
17516 Data type representing the configuration of @code{slim-service-type}.
17519 @item @code{allow-empty-passwords?} (default: @code{#t})
17520 Whether to allow logins with empty passwords.
17522 @item @code{auto-login?} (default: @code{#f})
17523 @itemx @code{default-user} (default: @code{""})
17524 When @code{auto-login?} is false, SLiM presents a log-in screen.
17526 When @code{auto-login?} is true, SLiM logs in directly as
17527 @code{default-user}.
17529 @item @code{theme} (default: @code{%default-slim-theme})
17530 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
17531 The graphical theme to use and its name.
17533 @item @code{auto-login-session} (default: @code{#f})
17534 If true, this must be the name of the executable to start as the default
17535 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
17537 If false, a session described by one of the available @file{.desktop}
17538 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
17542 You must install at least one window manager in the system profile or in
17543 your user profile. Failing to do that, if @code{auto-login-session} is
17544 false, you will be unable to log in.
17547 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
17548 Configuration of the Xorg graphical server.
17550 @item @code{display} (default @code{":0"})
17551 The display on which to start the Xorg graphical server.
17553 @item @code{vt} (default @code{"vt7"})
17554 The VT on which to start the Xorg graphical server.
17556 @item @code{xauth} (default: @code{xauth})
17557 The XAuth package to use.
17559 @item @code{shepherd} (default: @code{shepherd})
17560 The Shepherd package used when invoking @command{halt} and
17563 @item @code{sessreg} (default: @code{sessreg})
17564 The sessreg package used in order to register the session.
17566 @item @code{slim} (default: @code{slim})
17567 The SLiM package to use.
17571 @defvr {Scheme Variable} %default-theme
17572 @defvrx {Scheme Variable} %default-theme-name
17573 The default SLiM theme and its name.
17577 @deftp {Data Type} sddm-configuration
17578 This is the data type representing the SDDM service configuration.
17581 @item @code{display-server} (default: "x11")
17582 Select display server to use for the greeter. Valid values are
17583 @samp{"x11"} or @samp{"wayland"}.
17585 @item @code{numlock} (default: "on")
17586 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
17588 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
17589 Command to run when halting.
17591 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
17592 Command to run when rebooting.
17594 @item @code{theme} (default "maldives")
17595 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
17596 @samp{"maldives"} or @samp{"maya"}.
17598 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
17599 Directory to look for themes.
17601 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
17602 Directory to look for faces.
17604 @item @code{default-path} (default "/run/current-system/profile/bin")
17605 Default PATH to use.
17607 @item @code{minimum-uid} (default: 1000)
17608 Minimum UID displayed in SDDM and allowed for log-in.
17610 @item @code{maximum-uid} (default: 2000)
17611 Maximum UID to display in SDDM.
17613 @item @code{remember-last-user?} (default #t)
17614 Remember last user.
17616 @item @code{remember-last-session?} (default #t)
17617 Remember last session.
17619 @item @code{hide-users} (default "")
17620 Usernames to hide from SDDM greeter.
17622 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
17623 Users with shells listed will be hidden from the SDDM greeter.
17625 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
17626 Script to run before starting a wayland session.
17628 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
17629 Directory to look for desktop files starting wayland sessions.
17631 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
17632 Configuration of the Xorg graphical server.
17634 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
17637 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
17640 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
17641 Script to run after starting xorg-server.
17643 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
17644 Script to run before stopping xorg-server.
17646 @item @code{xsession-command} (default: @code{xinitrc})
17647 Script to run before starting a X session.
17649 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
17650 Directory to look for desktop files starting X sessions.
17652 @item @code{minimum-vt} (default: 7)
17655 @item @code{auto-login-user} (default "")
17656 User to use for auto-login.
17658 @item @code{auto-login-session} (default "")
17659 Desktop file to use for auto-login.
17661 @item @code{relogin?} (default #f)
17662 Relogin after logout.
17667 @cindex login manager
17669 @defvr {Scheme Variable} sddm-service-type
17670 This is the type of the service to run the
17671 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
17672 must be a @code{sddm-configuration} record (see below).
17674 Here's an example use:
17677 (service sddm-service-type
17678 (sddm-configuration
17679 (auto-login-user "alice")
17680 (auto-login-session "xfce.desktop")))
17684 @deftp {Data Type} sddm-configuration
17685 This data type represents the configuration of the SDDM login manager.
17686 The available fields are:
17689 @item @code{sddm} (default: @code{sddm})
17690 The SDDM package to use.
17692 @item @code{display-server} (default: @code{"x11"})
17693 This must be either @code{"x11"} or @code{"wayland"}.
17695 @c FIXME: Add more fields.
17697 @item @code{auto-login-user} (default: @code{""})
17698 If non-empty, this is the user account under which to log in
17701 @item @code{auto-login-session} (default: @code{""})
17702 If non-empty, this is the @file{.desktop} file name to use as the
17703 auto-login session.
17707 @cindex Xorg, configuration
17708 @deftp {Data Type} xorg-configuration
17709 This data type represents the configuration of the Xorg graphical display
17710 server. Note that there is no Xorg service; instead, the X server is started
17711 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
17712 of these display managers aggregates an @code{xorg-configuration} record.
17715 @item @code{modules} (default: @code{%default-xorg-modules})
17716 This is a list of @dfn{module packages} loaded by the Xorg
17717 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
17719 @item @code{fonts} (default: @code{%default-xorg-fonts})
17720 This is a list of font directories to add to the server's @dfn{font path}.
17722 @item @code{drivers} (default: @code{'()})
17723 This must be either the empty list, in which case Xorg chooses a graphics
17724 driver automatically, or a list of driver names that will be tried in this
17725 order---e.g., @code{("modesetting" "vesa")}.
17727 @item @code{resolutions} (default: @code{'()})
17728 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
17729 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
17732 @cindex keyboard layout, for Xorg
17733 @cindex keymap, for Xorg
17734 @item @code{keyboard-layout} (default: @code{#f})
17735 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
17736 English (``qwerty'') for a 105-key PC keyboard.
17738 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
17739 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
17740 information on how to specify the keyboard layout.
17742 @item @code{extra-config} (default: @code{'()})
17743 This is a list of strings or objects appended to the configuration file. It
17744 is used to pass extra text to be added verbatim to the configuration file.
17746 @item @code{server} (default: @code{xorg-server})
17747 This is the package providing the Xorg server.
17749 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
17750 This is the list of command-line arguments to pass to the X server. The
17751 default is @code{-nolisten tcp}.
17755 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
17756 [@var{login-manager-service-type}]
17757 Tell the log-in manager (of type @var{login-manager-service-type}) to use
17758 @var{config}, an @code{<xorg-configuration>} record.
17760 Since the Xorg configuration is embedded in the log-in manager's
17761 configuration---e.g., @code{gdm-configuration}---this procedure provides a
17762 shorthand to set the Xorg configuration.
17765 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
17766 Return a @code{startx} script in which the modules, fonts, etc. specified
17767 in @var{config}, are available. The result should be used in place of
17770 Usually the X server is started by a login manager.
17774 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
17775 Add @var{package}, a package for a screen locker or screen saver whose
17776 command is @var{program}, to the set of setuid programs and add a PAM entry
17777 for it. For example:
17780 (screen-locker-service xlockmore "xlock")
17783 makes the good ol' XlockMore usable.
17787 @node Printing Services
17788 @subsection Printing Services
17790 @cindex printer support with CUPS
17791 The @code{(gnu services cups)} module provides a Guix service definition
17792 for the CUPS printing service. To add printer support to a Guix
17793 system, add a @code{cups-service} to the operating system definition:
17795 @deffn {Scheme Variable} cups-service-type
17796 The service type for the CUPS print server. Its value should be a valid
17797 CUPS configuration (see below). To use the default settings, simply
17800 (service cups-service-type)
17804 The CUPS configuration controls the basic things about your CUPS
17805 installation: what interfaces it listens on, what to do if a print job
17806 fails, how much logging to do, and so on. To actually add a printer,
17807 you have to visit the @url{http://localhost:631} URL, or use a tool such
17808 as GNOME's printer configuration services. By default, configuring a
17809 CUPS service will generate a self-signed certificate if needed, for
17810 secure connections to the print server.
17812 Suppose you want to enable the Web interface of CUPS and also add
17813 support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
17814 package and for HP printers @i{via} the @code{hplip-minimal} package.
17815 You can do that directly, like this (you need to use the
17816 @code{(gnu packages cups)} module):
17819 (service cups-service-type
17820 (cups-configuration
17821 (web-interface? #t)
17823 (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
17826 Note: If you wish to use the Qt5 based GUI which comes with the hplip
17827 package then it is suggested that you install the @code{hplip} package,
17828 either in your OS configuration file or as your user.
17830 The available configuration parameters follow. Each parameter
17831 definition is preceded by its type; for example, @samp{string-list foo}
17832 indicates that the @code{foo} parameter should be specified as a list of
17833 strings. There is also a way to specify the configuration as a string,
17834 if you have an old @code{cupsd.conf} file that you want to port over
17835 from some other system; see the end for more details.
17837 @c The following documentation was initially generated by
17838 @c (generate-documentation) in (gnu services cups). Manually maintained
17839 @c documentation is better, so we shouldn't hesitate to edit below as
17840 @c needed. However if the change you want to make to this documentation
17841 @c can be done in an automated way, it's probably easier to change
17842 @c (generate-documentation) than to make it below and have to deal with
17843 @c the churn as CUPS updates.
17846 Available @code{cups-configuration} fields are:
17848 @deftypevr {@code{cups-configuration} parameter} package cups
17852 @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list brlaser cups-filters epson-inkjet-printer-escpr foomatic-filters hplip-minimal splix)})
17853 Drivers and other extensions to the CUPS package.
17856 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
17857 Configuration of where to write logs, what directories to use for print
17858 spools, and related privileged configuration parameters.
17860 Available @code{files-configuration} fields are:
17862 @deftypevr {@code{files-configuration} parameter} log-location access-log
17863 Defines the access log filename. Specifying a blank filename disables
17864 access log generation. The value @code{stderr} causes log entries to be
17865 sent to the standard error file when the scheduler is running in the
17866 foreground, or to the system log daemon when run in the background. The
17867 value @code{syslog} causes log entries to be sent to the system log
17868 daemon. The server name may be included in filenames using the string
17869 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
17871 Defaults to @samp{"/var/log/cups/access_log"}.
17874 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
17875 Where CUPS should cache data.
17877 Defaults to @samp{"/var/cache/cups"}.
17880 @deftypevr {@code{files-configuration} parameter} string config-file-perm
17881 Specifies the permissions for all configuration files that the scheduler
17884 Note that the permissions for the printers.conf file are currently
17885 masked to only allow access from the scheduler user (typically root).
17886 This is done because printer device URIs sometimes contain sensitive
17887 authentication information that should not be generally known on the
17888 system. There is no way to disable this security feature.
17890 Defaults to @samp{"0640"}.
17893 @deftypevr {@code{files-configuration} parameter} log-location error-log
17894 Defines the error log filename. Specifying a blank filename disables
17895 error log generation. The value @code{stderr} causes log entries to be
17896 sent to the standard error file when the scheduler is running in the
17897 foreground, or to the system log daemon when run in the background. The
17898 value @code{syslog} causes log entries to be sent to the system log
17899 daemon. The server name may be included in filenames using the string
17900 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
17902 Defaults to @samp{"/var/log/cups/error_log"}.
17905 @deftypevr {@code{files-configuration} parameter} string fatal-errors
17906 Specifies which errors are fatal, causing the scheduler to exit. The
17911 No errors are fatal.
17914 All of the errors below are fatal.
17917 Browsing initialization errors are fatal, for example failed connections
17918 to the DNS-SD daemon.
17921 Configuration file syntax errors are fatal.
17924 Listen or Port errors are fatal, except for IPv6 failures on the
17925 loopback or @code{any} addresses.
17928 Log file creation or write errors are fatal.
17931 Bad startup file permissions are fatal, for example shared TLS
17932 certificate and key files with world-read permissions.
17935 Defaults to @samp{"all -browse"}.
17938 @deftypevr {@code{files-configuration} parameter} boolean file-device?
17939 Specifies whether the file pseudo-device can be used for new printer
17940 queues. The URI @uref{file:///dev/null} is always allowed.
17942 Defaults to @samp{#f}.
17945 @deftypevr {@code{files-configuration} parameter} string group
17946 Specifies the group name or ID that will be used when executing external
17949 Defaults to @samp{"lp"}.
17952 @deftypevr {@code{files-configuration} parameter} string log-file-perm
17953 Specifies the permissions for all log files that the scheduler writes.
17955 Defaults to @samp{"0644"}.
17958 @deftypevr {@code{files-configuration} parameter} log-location page-log
17959 Defines the page log filename. Specifying a blank filename disables
17960 page log generation. The value @code{stderr} causes log entries to be
17961 sent to the standard error file when the scheduler is running in the
17962 foreground, or to the system log daemon when run in the background. The
17963 value @code{syslog} causes log entries to be sent to the system log
17964 daemon. The server name may be included in filenames using the string
17965 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
17967 Defaults to @samp{"/var/log/cups/page_log"}.
17970 @deftypevr {@code{files-configuration} parameter} string remote-root
17971 Specifies the username that is associated with unauthenticated accesses
17972 by clients claiming to be the root user. The default is @code{remroot}.
17974 Defaults to @samp{"remroot"}.
17977 @deftypevr {@code{files-configuration} parameter} file-name request-root
17978 Specifies the directory that contains print jobs and other HTTP request
17981 Defaults to @samp{"/var/spool/cups"}.
17984 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
17985 Specifies the level of security sandboxing that is applied to print
17986 filters, backends, and other child processes of the scheduler; either
17987 @code{relaxed} or @code{strict}. This directive is currently only
17988 used/supported on macOS.
17990 Defaults to @samp{strict}.
17993 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
17994 Specifies the location of TLS certificates and private keys. CUPS will
17995 look for public and private keys in this directory: @file{.crt} files
17996 for PEM-encoded certificates and corresponding @file{.key} files for
17997 PEM-encoded private keys.
17999 Defaults to @samp{"/etc/cups/ssl"}.
18002 @deftypevr {@code{files-configuration} parameter} file-name server-root
18003 Specifies the directory containing the server configuration files.
18005 Defaults to @samp{"/etc/cups"}.
18008 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
18009 Specifies whether the scheduler calls fsync(2) after writing
18010 configuration or state files.
18012 Defaults to @samp{#f}.
18015 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
18016 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
18019 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
18020 Specifies the directory where temporary files are stored.
18022 Defaults to @samp{"/var/spool/cups/tmp"}.
18025 @deftypevr {@code{files-configuration} parameter} string user
18026 Specifies the user name or ID that is used when running external
18029 Defaults to @samp{"lp"}.
18032 @deftypevr {@code{files-configuration} parameter} string set-env
18033 Set the specified environment variable to be passed to child processes.
18035 Defaults to @samp{"variable value"}.
18039 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
18040 Specifies the logging level for the AccessLog file. The @code{config}
18041 level logs when printers and classes are added, deleted, or modified and
18042 when configuration files are accessed or updated. The @code{actions}
18043 level logs when print jobs are submitted, held, released, modified, or
18044 canceled, and any of the conditions for @code{config}. The @code{all}
18045 level logs all requests.
18047 Defaults to @samp{actions}.
18050 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
18051 Specifies whether to purge job history data automatically when it is no
18052 longer required for quotas.
18054 Defaults to @samp{#f}.
18057 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
18058 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
18059 For example, @samp{"_cups" "_print"} will tell network clients that both
18060 CUPS sharing and IPP Everywhere are supported.
18062 Defaults to @samp{"_cups"}.
18065 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
18066 Specifies which protocols to use for local printer sharing.
18068 Defaults to @samp{dnssd}.
18071 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
18072 Specifies whether the CUPS web interface is advertised.
18074 Defaults to @samp{#f}.
18077 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
18078 Specifies whether shared printers are advertised.
18080 Defaults to @samp{#f}.
18083 @deftypevr {@code{cups-configuration} parameter} string classification
18084 Specifies the security classification of the server. Any valid banner
18085 name can be used, including @samp{"classified"}, @samp{"confidential"},
18086 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
18087 banner can be omitted to disable secure printing functions.
18089 Defaults to @samp{""}.
18092 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
18093 Specifies whether users may override the classification (cover page) of
18094 individual print jobs using the @code{job-sheets} option.
18096 Defaults to @samp{#f}.
18099 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
18100 Specifies the default type of authentication to use.
18102 Defaults to @samp{Basic}.
18105 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
18106 Specifies whether encryption will be used for authenticated requests.
18108 Defaults to @samp{Required}.
18111 @deftypevr {@code{cups-configuration} parameter} string default-language
18112 Specifies the default language to use for text and web content.
18114 Defaults to @samp{"en"}.
18117 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
18118 Specifies the default paper size for new print queues. @samp{"Auto"}
18119 uses a locale-specific default, while @samp{"None"} specifies there is
18120 no default paper size. Specific size names are typically
18121 @samp{"Letter"} or @samp{"A4"}.
18123 Defaults to @samp{"Auto"}.
18126 @deftypevr {@code{cups-configuration} parameter} string default-policy
18127 Specifies the default access policy to use.
18129 Defaults to @samp{"default"}.
18132 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
18133 Specifies whether local printers are shared by default.
18135 Defaults to @samp{#t}.
18138 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
18139 Specifies the delay for updating of configuration and state files, in
18140 seconds. A value of 0 causes the update to happen as soon as possible,
18141 typically within a few milliseconds.
18143 Defaults to @samp{30}.
18146 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
18147 Specifies what to do when an error occurs. Possible values are
18148 @code{abort-job}, which will discard the failed print job;
18149 @code{retry-job}, which will retry the job at a later time;
18150 @code{retry-current-job}, which retries the failed job immediately; and
18151 @code{stop-printer}, which stops the printer.
18153 Defaults to @samp{stop-printer}.
18156 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
18157 Specifies the maximum cost of filters that are run concurrently, which
18158 can be used to minimize disk, memory, and CPU resource problems. A
18159 limit of 0 disables filter limiting. An average print to a
18160 non-PostScript printer needs a filter limit of about 200. A PostScript
18161 printer needs about half that (100). Setting the limit below these
18162 thresholds will effectively limit the scheduler to printing a single job
18165 Defaults to @samp{0}.
18168 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
18169 Specifies the scheduling priority of filters that are run to print a
18170 job. The nice value ranges from 0, the highest priority, to 19, the
18173 Defaults to @samp{0}.
18176 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
18177 Specifies whether to do reverse lookups on connecting clients. The
18178 @code{double} setting causes @code{cupsd} to verify that the hostname
18179 resolved from the address matches one of the addresses returned for that
18180 hostname. Double lookups also prevent clients with unregistered
18181 addresses from connecting to your server. Only set this option to
18182 @code{#t} or @code{double} if absolutely required.
18184 Defaults to @samp{#f}.
18187 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
18188 Specifies the number of seconds to wait before killing the filters and
18189 backend associated with a canceled or held job.
18191 Defaults to @samp{30}.
18194 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
18195 Specifies the interval between retries of jobs in seconds. This is
18196 typically used for fax queues but can also be used with normal print
18197 queues whose error policy is @code{retry-job} or
18198 @code{retry-current-job}.
18200 Defaults to @samp{30}.
18203 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
18204 Specifies the number of retries that are done for jobs. This is
18205 typically used for fax queues but can also be used with normal print
18206 queues whose error policy is @code{retry-job} or
18207 @code{retry-current-job}.
18209 Defaults to @samp{5}.
18212 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
18213 Specifies whether to support HTTP keep-alive connections.
18215 Defaults to @samp{#t}.
18218 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
18219 Specifies how long an idle client connection remains open, in seconds.
18221 Defaults to @samp{30}.
18224 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
18225 Specifies the maximum size of print files, IPP requests, and HTML form
18226 data. A limit of 0 disables the limit check.
18228 Defaults to @samp{0}.
18231 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
18232 Listens on the specified interfaces for connections. Valid values are
18233 of the form @var{address}:@var{port}, where @var{address} is either an
18234 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
18235 indicate all addresses. Values can also be file names of local UNIX
18236 domain sockets. The Listen directive is similar to the Port directive
18237 but allows you to restrict access to specific interfaces or networks.
18240 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
18241 Specifies the number of pending connections that will be allowed. This
18242 normally only affects very busy servers that have reached the MaxClients
18243 limit, but can also be triggered by large numbers of simultaneous
18244 connections. When the limit is reached, the operating system will
18245 refuse additional connections until the scheduler can accept the pending
18248 Defaults to @samp{128}.
18251 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
18252 Specifies a set of additional access controls.
18254 Available @code{location-access-controls} fields are:
18256 @deftypevr {@code{location-access-controls} parameter} file-name path
18257 Specifies the URI path to which the access control applies.
18260 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
18261 Access controls for all access to this path, in the same format as the
18262 @code{access-controls} of @code{operation-access-control}.
18264 Defaults to @samp{()}.
18267 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
18268 Access controls for method-specific access to this path.
18270 Defaults to @samp{()}.
18272 Available @code{method-access-controls} fields are:
18274 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
18275 If @code{#t}, apply access controls to all methods except the listed
18276 methods. Otherwise apply to only the listed methods.
18278 Defaults to @samp{#f}.
18281 @deftypevr {@code{method-access-controls} parameter} method-list methods
18282 Methods to which this access control applies.
18284 Defaults to @samp{()}.
18287 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
18288 Access control directives, as a list of strings. Each string should be
18289 one directive, such as @samp{"Order allow,deny"}.
18291 Defaults to @samp{()}.
18296 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
18297 Specifies the number of debugging messages that are retained for logging
18298 if an error occurs in a print job. Debug messages are logged regardless
18299 of the LogLevel setting.
18301 Defaults to @samp{100}.
18304 @deftypevr {@code{cups-configuration} parameter} log-level log-level
18305 Specifies the level of logging for the ErrorLog file. The value
18306 @code{none} stops all logging while @code{debug2} logs everything.
18308 Defaults to @samp{info}.
18311 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
18312 Specifies the format of the date and time in the log files. The value
18313 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
18315 Defaults to @samp{standard}.
18318 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
18319 Specifies the maximum number of simultaneous clients that are allowed by
18322 Defaults to @samp{100}.
18325 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
18326 Specifies the maximum number of simultaneous clients that are allowed
18327 from a single address.
18329 Defaults to @samp{100}.
18332 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
18333 Specifies the maximum number of copies that a user can print of each
18336 Defaults to @samp{9999}.
18339 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
18340 Specifies the maximum time a job may remain in the @code{indefinite}
18341 hold state before it is canceled. A value of 0 disables cancellation of
18344 Defaults to @samp{0}.
18347 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
18348 Specifies the maximum number of simultaneous jobs that are allowed. Set
18349 to 0 to allow an unlimited number of jobs.
18351 Defaults to @samp{500}.
18354 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
18355 Specifies the maximum number of simultaneous jobs that are allowed per
18356 printer. A value of 0 allows up to MaxJobs jobs per printer.
18358 Defaults to @samp{0}.
18361 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
18362 Specifies the maximum number of simultaneous jobs that are allowed per
18363 user. A value of 0 allows up to MaxJobs jobs per user.
18365 Defaults to @samp{0}.
18368 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
18369 Specifies the maximum time a job may take to print before it is
18370 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
18372 Defaults to @samp{10800}.
18375 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
18376 Specifies the maximum size of the log files before they are rotated, in
18377 bytes. The value 0 disables log rotation.
18379 Defaults to @samp{1048576}.
18382 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
18383 Specifies the maximum amount of time to allow between files in a
18384 multiple file print job, in seconds.
18386 Defaults to @samp{300}.
18389 @deftypevr {@code{cups-configuration} parameter} string page-log-format
18390 Specifies the format of PageLog lines. Sequences beginning with percent
18391 (@samp{%}) characters are replaced with the corresponding information,
18392 while all other characters are copied literally. The following percent
18393 sequences are recognized:
18397 insert a single percent character
18400 insert the value of the specified IPP attribute
18403 insert the number of copies for the current page
18406 insert the current page number
18409 insert the current date and time in common log format
18415 insert the printer name
18418 insert the username
18421 A value of the empty string disables page logging. The string @code{%p
18422 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
18423 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
18426 Defaults to @samp{""}.
18429 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
18430 Passes the specified environment variable(s) to child processes; a list
18433 Defaults to @samp{()}.
18436 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
18437 Specifies named access control policies.
18439 Available @code{policy-configuration} fields are:
18441 @deftypevr {@code{policy-configuration} parameter} string name
18442 Name of the policy.
18445 @deftypevr {@code{policy-configuration} parameter} string job-private-access
18446 Specifies an access list for a job's private values. @code{@@ACL} maps
18447 to the printer's requesting-user-name-allowed or
18448 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
18449 owner. @code{@@SYSTEM} maps to the groups listed for the
18450 @code{system-group} field of the @code{files-config} configuration,
18451 which is reified into the @code{cups-files.conf(5)} file. Other
18452 possible elements of the access list include specific user names, and
18453 @code{@@@var{group}} to indicate members of a specific group. The
18454 access list may also be simply @code{all} or @code{default}.
18456 Defaults to @samp{"@@OWNER @@SYSTEM"}.
18459 @deftypevr {@code{policy-configuration} parameter} string job-private-values
18460 Specifies the list of job values to make private, or @code{all},
18461 @code{default}, or @code{none}.
18463 Defaults to @samp{"job-name job-originating-host-name
18464 job-originating-user-name phone"}.
18467 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
18468 Specifies an access list for a subscription's private values.
18469 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
18470 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
18471 owner. @code{@@SYSTEM} maps to the groups listed for the
18472 @code{system-group} field of the @code{files-config} configuration,
18473 which is reified into the @code{cups-files.conf(5)} file. Other
18474 possible elements of the access list include specific user names, and
18475 @code{@@@var{group}} to indicate members of a specific group. The
18476 access list may also be simply @code{all} or @code{default}.
18478 Defaults to @samp{"@@OWNER @@SYSTEM"}.
18481 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
18482 Specifies the list of job values to make private, or @code{all},
18483 @code{default}, or @code{none}.
18485 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
18486 notify-subscriber-user-name notify-user-data"}.
18489 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
18490 Access control by IPP operation.
18492 Defaults to @samp{()}.
18496 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
18497 Specifies whether job files (documents) are preserved after a job is
18498 printed. If a numeric value is specified, job files are preserved for
18499 the indicated number of seconds after printing. Otherwise a boolean
18500 value applies indefinitely.
18502 Defaults to @samp{86400}.
18505 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
18506 Specifies whether the job history is preserved after a job is printed.
18507 If a numeric value is specified, the job history is preserved for the
18508 indicated number of seconds after printing. If @code{#t}, the job
18509 history is preserved until the MaxJobs limit is reached.
18511 Defaults to @samp{#t}.
18514 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
18515 Specifies the amount of time to wait for job completion before
18516 restarting the scheduler.
18518 Defaults to @samp{30}.
18521 @deftypevr {@code{cups-configuration} parameter} string rip-cache
18522 Specifies the maximum amount of memory to use when converting documents
18523 into bitmaps for a printer.
18525 Defaults to @samp{"128m"}.
18528 @deftypevr {@code{cups-configuration} parameter} string server-admin
18529 Specifies the email address of the server administrator.
18531 Defaults to @samp{"root@@localhost.localdomain"}.
18534 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
18535 The ServerAlias directive is used for HTTP Host header validation when
18536 clients connect to the scheduler from external interfaces. Using the
18537 special name @code{*} can expose your system to known browser-based DNS
18538 rebinding attacks, even when accessing sites through a firewall. If the
18539 auto-discovery of alternate names does not work, we recommend listing
18540 each alternate name with a ServerAlias directive instead of using
18543 Defaults to @samp{*}.
18546 @deftypevr {@code{cups-configuration} parameter} string server-name
18547 Specifies the fully-qualified host name of the server.
18549 Defaults to @samp{"localhost"}.
18552 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
18553 Specifies what information is included in the Server header of HTTP
18554 responses. @code{None} disables the Server header. @code{ProductOnly}
18555 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
18556 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
18557 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
18558 the output of the @code{uname} command. @code{Full} reports @code{CUPS
18559 2.0.0 (@var{uname}) IPP/2.0}.
18561 Defaults to @samp{Minimal}.
18564 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
18565 Listens on the specified interfaces for encrypted connections. Valid
18566 values are of the form @var{address}:@var{port}, where @var{address} is
18567 either an IPv6 address enclosed in brackets, an IPv4 address, or
18568 @code{*} to indicate all addresses.
18570 Defaults to @samp{()}.
18573 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
18574 Sets encryption options. By default, CUPS only supports encryption
18575 using TLS v1.0 or higher using known secure cipher suites. Security is
18576 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
18577 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
18578 suites, which are required for some older clients. The @code{AllowSSL3} option
18579 enables SSL v3.0, which is required for some older clients that do not support
18580 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
18581 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
18582 protocol version to TLS v1.1.
18584 Defaults to @samp{()}.
18587 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
18588 Specifies whether the scheduler requires clients to strictly adhere to
18589 the IPP specifications.
18591 Defaults to @samp{#f}.
18594 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
18595 Specifies the HTTP request timeout, in seconds.
18597 Defaults to @samp{300}.
18601 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
18602 Specifies whether the web interface is enabled.
18604 Defaults to @samp{#f}.
18607 At this point you're probably thinking ``oh dear, Guix manual, I like
18608 you but you can stop already with the configuration options''. Indeed.
18609 However, one more point: it could be that you have an existing
18610 @code{cupsd.conf} that you want to use. In that case, you can pass an
18611 @code{opaque-cups-configuration} as the configuration of a
18612 @code{cups-service-type}.
18614 Available @code{opaque-cups-configuration} fields are:
18616 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
18620 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
18621 The contents of the @code{cupsd.conf}, as a string.
18624 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
18625 The contents of the @code{cups-files.conf} file, as a string.
18628 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
18629 strings of the same name, you could instantiate a CUPS service like
18633 (service cups-service-type
18634 (opaque-cups-configuration
18635 (cupsd.conf cupsd.conf)
18636 (cups-files.conf cups-files.conf)))
18640 @node Desktop Services
18641 @subsection Desktop Services
18643 The @code{(gnu services desktop)} module provides services that are
18644 usually useful in the context of a ``desktop'' setup---that is, on a
18645 machine running a graphical display server, possibly with graphical user
18646 interfaces, etc. It also defines services that provide specific desktop
18647 environments like GNOME, Xfce or MATE.
18649 To simplify things, the module defines a variable containing the set of
18650 services that users typically expect on a machine with a graphical
18651 environment and networking:
18653 @defvr {Scheme Variable} %desktop-services
18654 This is a list of services that builds upon @code{%base-services} and
18655 adds or adjusts services for a typical ``desktop'' setup.
18657 In particular, it adds a graphical login manager (@pxref{X Window,
18658 @code{gdm-service-type}}), screen lockers, a network management tool
18659 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
18660 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
18661 energy and color management services, the @code{elogind} login and seat
18662 manager, the Polkit privilege service, the GeoClue location service, the
18663 AccountsService daemon that allows authorized users change system passwords,
18664 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
18665 name service switch service configured to be able to use @code{nss-mdns}
18666 (@pxref{Name Service Switch, mDNS}).
18669 The @code{%desktop-services} variable can be used as the @code{services}
18670 field of an @code{operating-system} declaration (@pxref{operating-system
18671 Reference, @code{services}}).
18673 Additionally, the @code{gnome-desktop-service-type},
18674 @code{xfce-desktop-service}, @code{mate-desktop-service-type},
18675 @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
18676 procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
18677 ``add GNOME'' means that system-level services like the backlight adjustment
18678 helpers and the power management utilities are added to the system, extending
18679 @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
18680 elevated privileges on a limited number of special-purpose system interfaces.
18681 Additionally, adding a service made by @code{gnome-desktop-service-type} adds
18682 the GNOME metapackage to the system profile. Likewise, adding the Xfce
18683 service not only adds the @code{xfce} metapackage to the system profile, but
18684 it also gives the Thunar file manager the ability to open a ``root-mode'' file
18685 management window, if the user authenticates using the administrator's
18686 password via the standard polkit graphical interface. To ``add MATE'' means
18687 that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
18688 to operate with elevated privileges on a limited number of special-purpose
18689 system interfaces. Additionally, adding a service of type
18690 @code{mate-desktop-service-type} adds the MATE metapackage to the system
18691 profile. ``Adding Enlightenment'' means that @code{dbus} is extended
18692 appropriately, and several of Enlightenment's binaries are set as setuid,
18693 allowing Enlightenment's screen locker and other functionality to work as
18696 The desktop environments in Guix use the Xorg display server by
18697 default. If you'd like to use the newer display server protocol
18698 called Wayland, you need to use the @code{sddm-service} instead of
18699 GDM as the graphical login manager. You should then
18700 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
18701 also try starting GNOME on Wayland manually from a TTY with the
18702 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
18703 gnome-session``. Currently only GNOME has support for Wayland.
18705 @defvr {Scheme Variable} gnome-desktop-service-type
18706 This is the type of the service that adds the @uref{https://www.gnome.org,
18707 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
18708 object (see below).
18710 This service adds the @code{gnome} package to the system profile, and extends
18711 polkit with the actions from @code{gnome-settings-daemon}.
18714 @deftp {Data Type} gnome-desktop-configuration
18715 Configuration record for the GNOME desktop environment.
18718 @item @code{gnome} (default: @code{gnome})
18719 The GNOME package to use.
18723 @defvr {Scheme Variable} xfce-desktop-service-type
18724 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
18725 desktop environment. Its value is an @code{xfce-desktop-configuration} object
18728 This service adds the @code{xfce} package to the system profile, and
18729 extends polkit with the ability for @code{thunar} to manipulate the file
18730 system as root from within a user session, after the user has authenticated
18731 with the administrator's password.
18733 Note that @code{xfce4-panel} and its plugin packages should be installed in
18734 the same profile to ensure compatibility. When using this service, you should
18735 add extra plugins (@code{xfce4-whiskermenu-plugin},
18736 @code{xfce4-weather-plugin}, etc.) to the @code{packages} field of your
18737 @code{operating-system}.
18740 @deftp {Data Type} xfce-desktop-configuration
18741 Configuration record for the Xfce desktop environment.
18744 @item @code{xfce} (default: @code{xfce})
18745 The Xfce package to use.
18749 @deffn {Scheme Variable} mate-desktop-service-type
18750 This is the type of the service that runs the @uref{https://mate-desktop.org/,
18751 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
18752 object (see below).
18754 This service adds the @code{mate} package to the system
18755 profile, and extends polkit with the actions from
18756 @code{mate-settings-daemon}.
18759 @deftp {Data Type} mate-desktop-configuration
18760 Configuration record for the MATE desktop environment.
18763 @item @code{mate} (default: @code{mate})
18764 The MATE package to use.
18768 @deffn {Scheme Variable} lxqt-desktop-service-type
18769 This is the type of the service that runs the @uref{https://lxqt.github.io,
18770 LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
18771 object (see below).
18773 This service adds the @code{lxqt} package to the system
18777 @deftp {Data Type} lxqt-desktop-configuration
18778 Configuration record for the LXQt desktop environment.
18781 @item @code{lxqt} (default: @code{lxqt})
18782 The LXQT package to use.
18786 @deffn {Scheme Variable} enlightenment-desktop-service-type
18787 Return a service that adds the @code{enlightenment} package to the system
18788 profile, and extends dbus with actions from @code{efl}.
18791 @deftp {Data Type} enlightenment-desktop-service-configuration
18793 @item @code{enlightenment} (default: @code{enlightenment})
18794 The enlightenment package to use.
18798 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
18799 the default @code{%desktop-services} variable doesn't include any of
18800 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
18801 @code{%desktop-services} in the @code{services} field of your
18802 @code{operating-system}:
18805 (use-modules (gnu))
18806 (use-service-modules desktop)
18809 ;; cons* adds items to the list given as its last argument.
18810 (services (cons* (service gnome-desktop-service-type)
18811 (service xfce-desktop-service)
18812 %desktop-services))
18816 These desktop environments will then be available as options in the
18817 graphical login window.
18819 The actual service definitions included in @code{%desktop-services} and
18820 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
18821 are described below.
18823 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
18824 Return a service that runs the ``system bus'', using @var{dbus}, with
18825 support for @var{services}.
18827 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
18828 facility. Its system bus is used to allow system services to communicate
18829 and to be notified of system-wide events.
18831 @var{services} must be a list of packages that provide an
18832 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
18833 and policy files. For example, to allow avahi-daemon to use the system bus,
18834 @var{services} must be equal to @code{(list avahi)}.
18837 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
18838 Return a service that runs the @code{elogind} login and
18839 seat management daemon. @uref{https://github.com/elogind/elogind,
18840 Elogind} exposes a D-Bus interface that can be used to know which users
18841 are logged in, know what kind of sessions they have open, suspend the
18842 system, inhibit system suspend, reboot the system, and other tasks.
18844 Elogind handles most system-level power events for a computer, for
18845 example suspending the system when a lid is closed, or shutting it down
18846 when the power button is pressed.
18848 The @var{config} keyword argument specifies the configuration for
18849 elogind, and should be the result of an @code{(elogind-configuration
18850 (@var{parameter} @var{value})...)} invocation. Available parameters and
18851 their default values are:
18854 @item kill-user-processes?
18856 @item kill-only-users
18858 @item kill-exclude-users
18860 @item inhibit-delay-max-seconds
18862 @item handle-power-key
18864 @item handle-suspend-key
18866 @item handle-hibernate-key
18868 @item handle-lid-switch
18870 @item handle-lid-switch-docked
18872 @item handle-lid-switch-external-power
18874 @item power-key-ignore-inhibited?
18876 @item suspend-key-ignore-inhibited?
18878 @item hibernate-key-ignore-inhibited?
18880 @item lid-switch-ignore-inhibited?
18882 @item holdoff-timeout-seconds
18886 @item idle-action-seconds
18888 @item runtime-directory-size-percent
18890 @item runtime-directory-size
18894 @item suspend-state
18895 @code{("mem" "standby" "freeze")}
18898 @item hibernate-state
18900 @item hibernate-mode
18901 @code{("platform" "shutdown")}
18902 @item hybrid-sleep-state
18904 @item hybrid-sleep-mode
18905 @code{("suspend" "platform" "shutdown")}
18909 @deffn {Scheme Procedure} accountsservice-service @
18910 [#:accountsservice @var{accountsservice}]
18911 Return a service that runs AccountsService, a system service that can
18912 list available accounts, change their passwords, and so on.
18913 AccountsService integrates with PolicyKit to enable unprivileged users
18914 to acquire the capability to modify their system configuration.
18915 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
18916 accountsservice web site} for more information.
18918 The @var{accountsservice} keyword argument is the @code{accountsservice}
18919 package to expose as a service.
18922 @deffn {Scheme Procedure} polkit-service @
18923 [#:polkit @var{polkit}]
18924 Return a service that runs the
18925 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
18926 management service}, which allows system administrators to grant access to
18927 privileged operations in a structured way. By querying the Polkit service, a
18928 privileged system component can know when it should grant additional
18929 capabilities to ordinary users. For example, an ordinary user can be granted
18930 the capability to suspend the system if the user is logged in locally.
18933 @defvr {Scheme Variable} polkit-wheel-service
18934 Service that adds the @code{wheel} group as admins to the Polkit
18935 service. This makes it so that users in the @code{wheel} group are queried
18936 for their own passwords when performing administrative actions instead of
18937 @code{root}'s, similar to the behaviour used by @code{sudo}.
18940 @defvr {Scheme Variable} upower-service-type
18941 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
18942 system-wide monitor for power consumption and battery levels, with the given
18943 configuration settings.
18945 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
18946 notably used by GNOME.
18949 @deftp {Data Type} upower-configuration
18950 Data type representation the configuration for UPower.
18954 @item @code{upower} (default: @var{upower})
18955 Package to use for @code{upower}.
18957 @item @code{watts-up-pro?} (default: @code{#f})
18958 Enable the Watts Up Pro device.
18960 @item @code{poll-batteries?} (default: @code{#t})
18961 Enable polling the kernel for battery level changes.
18963 @item @code{ignore-lid?} (default: @code{#f})
18964 Ignore the lid state, this can be useful if it's incorrect on a device.
18966 @item @code{use-percentage-for-policy?} (default: @code{#f})
18967 Whether battery percentage based policy should be used. The default is to use
18968 the time left, change to @code{#t} to use the percentage.
18970 @item @code{percentage-low} (default: @code{10})
18971 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
18972 at which the battery is considered low.
18974 @item @code{percentage-critical} (default: @code{3})
18975 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
18976 at which the battery is considered critical.
18978 @item @code{percentage-action} (default: @code{2})
18979 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
18980 at which action will be taken.
18982 @item @code{time-low} (default: @code{1200})
18983 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
18984 seconds at which the battery is considered low.
18986 @item @code{time-critical} (default: @code{300})
18987 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
18988 seconds at which the battery is considered critical.
18990 @item @code{time-action} (default: @code{120})
18991 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
18992 seconds at which action will be taken.
18994 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
18995 The action taken when @code{percentage-action} or @code{time-action} is
18996 reached (depending on the configuration of @code{use-percentage-for-policy?}).
18998 Possible values are:
19008 @code{'hybrid-sleep}.
19014 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
19015 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
19016 UDisks}, a @dfn{disk management} daemon that provides user interfaces
19017 with notifications and ways to mount/unmount disks. Programs that talk
19018 to UDisks include the @command{udisksctl} command, part of UDisks, and
19019 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
19020 it will only be able to use the file-system utilities installed in the
19021 system profile. For example if you want to be able to mount NTFS
19022 file-systems in read and write fashion, you'll need to have
19023 @code{ntfs-3g} installed system-wide.
19026 @deffn {Scheme Variable} colord-service-type
19027 This is the type of the service that runs @command{colord}, a system
19028 service with a D-Bus
19029 interface to manage the color profiles of input and output devices such as
19030 screens and scanners. It is notably used by the GNOME Color Manager graphical
19031 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
19032 site} for more information.
19035 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
19036 Return a configuration allowing an application to access GeoClue
19037 location data. @var{name} is the Desktop ID of the application, without
19038 the @code{.desktop} part. If @var{allowed?} is true, the application
19039 will have access to location information by default. The boolean
19040 @var{system?} value indicates whether an application is a system component
19041 or not. Finally @var{users} is a list of UIDs of all users for which
19042 this application is allowed location info access. An empty users list
19043 means that all users are allowed.
19046 @cindex scanner access
19047 @deffn {Scheme Procedure} sane-service-type
19048 This service provides access to scanners @i{via}
19049 @uref{http://www.sane-project.org, SANE} by installing the necessary udev
19053 @defvr {Scheme Variable} %standard-geoclue-applications
19054 The standard list of well-known GeoClue application configurations,
19055 granting authority to the GNOME date-and-time utility to ask for the
19056 current location in order to set the time zone, and allowing the
19057 IceCat and Epiphany web browsers to request location information.
19058 IceCat and Epiphany both query the user before allowing a web page to
19059 know the user's location.
19062 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
19063 [#:whitelist '()] @
19064 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
19065 [#:submit-data? #f]
19066 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
19067 [#:submission-nick "geoclue"] @
19068 [#:applications %standard-geoclue-applications]
19069 Return a service that runs the GeoClue location service. This service
19070 provides a D-Bus interface to allow applications to request access to a
19071 user's physical location, and optionally to add information to online
19072 location databases. See
19073 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
19074 web site} for more information.
19077 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
19078 [@w{#:auto-enable? #f}]
19079 Return a service that runs the @command{bluetoothd} daemon, which
19080 manages all the Bluetooth devices and provides a number of D-Bus
19081 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
19082 powered automatically at boot, which can be useful when using a
19083 bluetooth keyboard or mouse.
19085 Users need to be in the @code{lp} group to access the D-Bus service.
19088 @defvr {Scheme Variable} gnome-keyring-service-type
19089 This is the type of the service that adds the
19090 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
19091 value is a @code{gnome-keyring-configuration} object (see below).
19093 This service adds the @code{gnome-keyring} package to the system profile
19094 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
19095 a user's login keyring when they log in or setting its password with passwd.
19098 @deftp {Data Type} gnome-keyring-configuration
19099 Configuration record for the GNOME Keyring service.
19102 @item @code{keyring} (default: @code{gnome-keyring})
19103 The GNOME keyring package to use.
19105 @item @code{pam-services}
19106 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
19107 services to extend, where @var{service} is the name of an existing
19108 service to extend and @var{kind} is one of @code{login} or
19111 If @code{login} is given, it adds an optional
19112 @code{pam_gnome_keyring.so} to the auth block without arguments and to
19113 the session block with @code{auto_start}. If @code{passwd} is given, it
19114 adds an optional @code{pam_gnome_keyring.so} to the password block
19117 By default, this field contains ``gdm-password'' with the value @code{login}
19118 and ``passwd'' is with the value @code{passwd}.
19123 @node Sound Services
19124 @subsection Sound Services
19126 @cindex sound support
19128 @cindex PulseAudio, sound support
19130 The @code{(gnu services sound)} module provides a service to configure the
19131 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
19132 preferred ALSA output driver.
19134 @deffn {Scheme Variable} alsa-service-type
19135 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
19136 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
19137 configuration file. The value for this type is a @command{alsa-configuration}
19138 record as in this example:
19141 (service alsa-service-type)
19144 See below for details about @code{alsa-configuration}.
19147 @deftp {Data Type} alsa-configuration
19148 Data type representing the configuration for @code{alsa-service}.
19151 @item @code{alsa-plugins} (default: @var{alsa-plugins})
19152 @code{alsa-plugins} package to use.
19154 @item @code{pulseaudio?} (default: @var{#t})
19155 Whether ALSA applications should transparently be made to use the
19156 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
19158 Using PulseAudio allows you to run several sound-producing applications
19159 at the same time and to individual control them @i{via}
19160 @command{pavucontrol}, among other things.
19162 @item @code{extra-options} (default: @var{""})
19163 String to append to the @file{/etc/asound.conf} file.
19168 Individual users who want to override the system configuration of ALSA can do
19169 it with the @file{~/.asoundrc} file:
19172 # In guix, we have to specify the absolute path for plugins.
19174 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
19177 # Routing ALSA to jack:
19178 # <http://jackaudio.org/faq/routing_alsa.html>.
19182 0 system:playback_1
19183 1 system:playback_2
19200 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
19203 @deffn {Scheme Variable} pulseaudio-service-type
19204 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
19205 sound server. It exists to allow system overrides of the default settings
19206 via @code{pulseaudio-configuration}, see below.
19209 This service overrides per-user configuration files. If you want
19210 PulseAudio to honor configuration files in @file{~/.config/pulse} you
19211 have to unset the environment variables @env{PULSE_CONFIG} and
19212 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
19216 This service on its own does not ensure, that the @code{pulseaudio} package
19217 exists on your machine. It merely adds configuration files for it, as
19218 detailed below. In the (admittedly unlikely) case, that you find yourself
19219 without a @code{pulseaudio} package, consider enabling it through the
19220 @code{alsa-service-type} above.
19224 @deftp {Data Type} pulseaudio-configuration
19225 Data type representing the configuration for @code{pulseaudio-service}.
19228 @item @code{client-conf} (default: @code{'()})
19229 List of settings to set in @file{client.conf}.
19230 Accepts a list of strings or a symbol-value pairs. A string will be
19231 inserted as-is with a newline added. A pair will be formatted as
19232 ``key = value'', again with a newline added.
19234 @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
19235 List of settings to set in @file{daemon.conf}, formatted just like
19238 @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
19239 Script file to use as @file{default.pa}.
19241 @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
19242 Script file to use as @file{system.pa}.
19246 @deffn {Scheme Variable} ladspa-service-type
19247 This service sets the @var{LADSPA_PATH} variable, so that programs, which
19248 respect it, e.g. PulseAudio, can load LADSPA plugins.
19250 The following example will setup the service to enable modules from the
19251 @code{swh-plugins} package:
19254 (service ladspa-service-type
19255 (ladspa-configuration (plugins (list swh-plugins))))
19258 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
19263 @node Database Services
19264 @subsection Database Services
19268 The @code{(gnu services databases)} module provides the following services.
19270 @subsubheading PostgreSQL
19272 The following example describes a PostgreSQL service with the default
19276 (service postgresql-service-type
19277 (postgresql-configuration
19278 (postgresql postgresql-10)))
19281 If the services fails to start, it may be due to an incompatible
19282 cluster already present in @var{data-directory}. Adjust it (or, if you
19283 don't need the cluster anymore, delete @var{data-directory}), then
19284 restart the service.
19286 Peer authentication is used by default and the @code{postgres} user
19287 account has no shell, which prevents the direct execution of @code{psql}
19288 commands as this user. To use @code{psql}, you can temporarily log in
19289 as @code{postgres} using a shell, create a PostgreSQL superuser with the
19290 same name as one of the system users and then create the associated
19294 sudo -u postgres -s /bin/sh
19295 createuser --interactive
19296 createdb $MY_USER_LOGIN # Replace appropriately.
19299 @deftp {Data Type} postgresql-configuration
19300 Data type representing the configuration for the
19301 @code{postgresql-service-type}.
19304 @item @code{postgresql}
19305 PostgreSQL package to use for the service.
19307 @item @code{port} (default: @code{5432})
19308 Port on which PostgreSQL should listen.
19310 @item @code{locale} (default: @code{"en_US.utf8"})
19311 Locale to use as the default when creating the database cluster.
19313 @item @code{config-file} (default: @code{(postgresql-config-file)})
19314 The configuration file to use when running PostgreSQL. The default
19315 behaviour uses the postgresql-config-file record with the default values
19318 @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
19319 Directory in which to store the data.
19321 @item @code{extension-packages} (default: @code{'()})
19322 @cindex postgresql extension-packages
19323 Additional extensions are loaded from packages listed in
19324 @var{extension-packages}. Extensions are available at runtime. For instance,
19325 to create a geographic database using the @code{postgis} extension, a user can
19326 configure the postgresql-service as in this example:
19330 (use-package-modules databases geo)
19334 ;; postgresql is required to run `psql' but postgis is not required for
19335 ;; proper operation.
19336 (packages (cons* postgresql %base-packages))
19339 (service postgresql-service-type
19340 (postgresql-configuration
19341 (postgresql postgresql-10)
19342 (extension-packages (list postgis))))
19346 Then the extension becomes visible and you can initialise an empty geographic
19347 database in this way:
19351 > create database postgistest;
19352 > \connect postgistest;
19353 > create extension postgis;
19354 > create extension postgis_topology;
19357 There is no need to add this field for contrib extensions such as hstore or
19358 dblink as they are already loadable by postgresql. This field is only
19359 required to add extensions provided by other packages.
19364 @deftp {Data Type} postgresql-config-file
19365 Data type representing the PostgreSQL configuration file. As shown in
19366 the following example, this can be used to customize the configuration
19367 of PostgreSQL. Note that you can use any G-expression or filename in
19368 place of this record, if you already have a configuration file you'd
19369 like to use for example.
19372 (service postgresql-service-type
19373 (postgresql-configuration
19375 (postgresql-config-file
19376 (log-destination "stderr")
19378 (plain-file "pg_hba.conf"
19380 local all all trust
19381 host all all 127.0.0.1/32 md5
19382 host all all ::1/128 md5"))
19384 '(("session_preload_libraries" "'auto_explain'")
19385 ("random_page_cost" "2")
19386 ("auto_explain.log_min_duration" "'100ms'")
19387 ("work_mem" "'500MB'")
19388 ("logging_collector" "on")
19389 ("log_directory" "'/var/log/postgresql'")))))))
19393 @item @code{log-destination} (default: @code{"syslog"})
19394 The logging method to use for PostgreSQL. Multiple values are accepted,
19395 separated by commas.
19397 @item @code{hba-file} (default: @code{%default-postgres-hba})
19398 Filename or G-expression for the host-based authentication
19401 @item @code{ident-file} (default: @code{%default-postgres-ident})
19402 Filename or G-expression for the user name mapping configuration.
19404 @item @code{extra-config} (default: @code{'()})
19405 List of additional keys and values to include in the PostgreSQL config
19406 file. Each entry in the list should be a list where the first element
19407 is the key, and the remaining elements are the values.
19412 @subsubheading MariaDB/MySQL
19414 @defvr {Scheme Variable} mysql-service-type
19415 This is the service type for a MySQL or MariaDB database server. Its value
19416 is a @code{mysql-configuration} object that specifies which package to use,
19417 as well as various settings for the @command{mysqld} daemon.
19420 @deftp {Data Type} mysql-configuration
19421 Data type representing the configuration of @var{mysql-service-type}.
19424 @item @code{mysql} (default: @var{mariadb})
19425 Package object of the MySQL database server, can be either @var{mariadb}
19428 For MySQL, a temporary root password will be displayed at activation time.
19429 For MariaDB, the root password is empty.
19431 @item @code{bind-address} (default: @code{"127.0.0.1"})
19432 The IP on which to listen for network connections. Use @code{"0.0.0.0"}
19433 to bind to all available network interfaces.
19435 @item @code{port} (default: @code{3306})
19436 TCP port on which the database server listens for incoming connections.
19438 @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
19439 Socket file to use for local (non-network) connections.
19441 @item @code{extra-content} (default: @code{""})
19442 Additional settings for the @file{my.cnf} configuration file.
19444 @item @code{auto-upgrade?} (default: @code{#t})
19445 Whether to automatically run @command{mysql_upgrade} after starting the
19446 service. This is necessary to upgrade the @dfn{system schema} after
19447 ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
19448 be disabled if you would rather do that manually.
19453 @subsubheading Memcached
19455 @defvr {Scheme Variable} memcached-service-type
19456 This is the service type for the @uref{https://memcached.org/,
19457 Memcached} service, which provides a distributed in memory cache. The
19458 value for the service type is a @code{memcached-configuration} object.
19462 (service memcached-service-type)
19465 @deftp {Data Type} memcached-configuration
19466 Data type representing the configuration of memcached.
19469 @item @code{memcached} (default: @code{memcached})
19470 The Memcached package to use.
19472 @item @code{interfaces} (default: @code{'("0.0.0.0")})
19473 Network interfaces on which to listen.
19475 @item @code{tcp-port} (default: @code{11211})
19476 Port on which to accept connections.
19478 @item @code{udp-port} (default: @code{11211})
19479 Port on which to accept UDP connections on, a value of 0 will disable
19480 listening on a UDP socket.
19482 @item @code{additional-options} (default: @code{'()})
19483 Additional command line options to pass to @code{memcached}.
19487 @subsubheading MongoDB
19489 @defvr {Scheme Variable} mongodb-service-type
19490 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
19491 The value for the service type is a @code{mongodb-configuration} object.
19495 (service mongodb-service-type)
19498 @deftp {Data Type} mongodb-configuration
19499 Data type representing the configuration of mongodb.
19502 @item @code{mongodb} (default: @code{mongodb})
19503 The MongoDB package to use.
19505 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
19506 The configuration file for MongoDB.
19508 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
19509 This value is used to create the directory, so that it exists and is
19510 owned by the mongodb user. It should match the data-directory which
19511 MongoDB is configured to use through the configuration file.
19515 @subsubheading Redis
19517 @defvr {Scheme Variable} redis-service-type
19518 This is the service type for the @uref{https://redis.io/, Redis}
19519 key/value store, whose value is a @code{redis-configuration} object.
19522 @deftp {Data Type} redis-configuration
19523 Data type representing the configuration of redis.
19526 @item @code{redis} (default: @code{redis})
19527 The Redis package to use.
19529 @item @code{bind} (default: @code{"127.0.0.1"})
19530 Network interface on which to listen.
19532 @item @code{port} (default: @code{6379})
19533 Port on which to accept connections on, a value of 0 will disable
19534 listening on a TCP socket.
19536 @item @code{working-directory} (default: @code{"/var/lib/redis"})
19537 Directory in which to store the database and related files.
19541 @node Mail Services
19542 @subsection Mail Services
19546 The @code{(gnu services mail)} module provides Guix service definitions
19547 for email services: IMAP, POP3, and LMTP servers, as well as mail
19548 transport agents (MTAs). Lots of acronyms! These services are detailed
19549 in the subsections below.
19551 @subsubheading Dovecot Service
19553 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
19554 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
19557 By default, Dovecot does not need much configuration; the default
19558 configuration object created by @code{(dovecot-configuration)} will
19559 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
19560 certificate will be generated for TLS-protected connections, though
19561 Dovecot will also listen on cleartext ports by default. There are a
19562 number of options, though, which mail administrators might need to change,
19563 and as is the case with other services, Guix allows the system
19564 administrator to specify these parameters via a uniform Scheme interface.
19566 For example, to specify that mail is located at @code{maildir~/.mail},
19567 one would instantiate the Dovecot service like this:
19570 (dovecot-service #:config
19571 (dovecot-configuration
19572 (mail-location "maildir:~/.mail")))
19575 The available configuration parameters follow. Each parameter
19576 definition is preceded by its type; for example, @samp{string-list foo}
19577 indicates that the @code{foo} parameter should be specified as a list of
19578 strings. There is also a way to specify the configuration as a string,
19579 if you have an old @code{dovecot.conf} file that you want to port over
19580 from some other system; see the end for more details.
19582 @c The following documentation was initially generated by
19583 @c (generate-documentation) in (gnu services mail). Manually maintained
19584 @c documentation is better, so we shouldn't hesitate to edit below as
19585 @c needed. However if the change you want to make to this documentation
19586 @c can be done in an automated way, it's probably easier to change
19587 @c (generate-documentation) than to make it below and have to deal with
19588 @c the churn as dovecot updates.
19590 Available @code{dovecot-configuration} fields are:
19592 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
19593 The dovecot package.
19596 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
19597 A list of IPs or hosts where to listen for connections. @samp{*}
19598 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
19599 interfaces. If you want to specify non-default ports or anything more
19600 complex, customize the address and port fields of the
19601 @samp{inet-listener} of the specific services you are interested in.
19604 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
19605 List of protocols we want to serve. Available protocols include
19606 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
19608 Available @code{protocol-configuration} fields are:
19610 @deftypevr {@code{protocol-configuration} parameter} string name
19611 The name of the protocol.
19614 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
19615 UNIX socket path to the master authentication server to find users.
19616 This is used by imap (for shared users) and lda.
19617 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
19620 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
19621 Space separated list of plugins to load.
19624 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
19625 Maximum number of IMAP connections allowed for a user from each IP
19626 address. NOTE: The username is compared case-sensitively.
19627 Defaults to @samp{10}.
19632 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
19633 List of services to enable. Available services include @samp{imap},
19634 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
19637 Available @code{service-configuration} fields are:
19639 @deftypevr {@code{service-configuration} parameter} string kind
19640 The service kind. Valid values include @code{director},
19641 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
19642 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
19643 @code{tcpwrap}, @code{quota-warning}, or anything else.
19646 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
19647 Listeners for the service. A listener is either a
19648 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
19649 an @code{inet-listener-configuration}.
19650 Defaults to @samp{()}.
19652 Available @code{unix-listener-configuration} fields are:
19654 @deftypevr {@code{unix-listener-configuration} parameter} string path
19655 Path to the file, relative to @code{base-dir} field. This is also used as
19659 @deftypevr {@code{unix-listener-configuration} parameter} string mode
19660 The access mode for the socket.
19661 Defaults to @samp{"0600"}.
19664 @deftypevr {@code{unix-listener-configuration} parameter} string user
19665 The user to own the socket.
19666 Defaults to @samp{""}.
19669 @deftypevr {@code{unix-listener-configuration} parameter} string group
19670 The group to own the socket.
19671 Defaults to @samp{""}.
19675 Available @code{fifo-listener-configuration} fields are:
19677 @deftypevr {@code{fifo-listener-configuration} parameter} string path
19678 Path to the file, relative to @code{base-dir} field. This is also used as
19682 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
19683 The access mode for the socket.
19684 Defaults to @samp{"0600"}.
19687 @deftypevr {@code{fifo-listener-configuration} parameter} string user
19688 The user to own the socket.
19689 Defaults to @samp{""}.
19692 @deftypevr {@code{fifo-listener-configuration} parameter} string group
19693 The group to own the socket.
19694 Defaults to @samp{""}.
19698 Available @code{inet-listener-configuration} fields are:
19700 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
19701 The protocol to listen for.
19704 @deftypevr {@code{inet-listener-configuration} parameter} string address
19705 The address on which to listen, or empty for all addresses.
19706 Defaults to @samp{""}.
19709 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
19710 The port on which to listen.
19713 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
19714 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
19716 Defaults to @samp{#t}.
19721 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
19722 Maximum number of simultaneous client connections per process. Once
19723 this number of connections is received, the next incoming connection
19724 will prompt Dovecot to spawn another process. If set to 0,
19725 @code{default-client-limit} is used instead.
19727 Defaults to @samp{0}.
19731 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
19732 Number of connections to handle before starting a new process.
19733 Typically the only useful values are 0 (unlimited) or 1. 1 is more
19734 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
19735 Defaults to @samp{1}.
19739 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
19740 Maximum number of processes that can exist for this service. If set to
19741 0, @code{default-process-limit} is used instead.
19743 Defaults to @samp{0}.
19747 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
19748 Number of processes to always keep waiting for more connections.
19749 Defaults to @samp{0}.
19752 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
19753 If you set @samp{service-count 0}, you probably need to grow
19755 Defaults to @samp{256000000}.
19760 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
19761 Dict configuration, as created by the @code{dict-configuration}
19764 Available @code{dict-configuration} fields are:
19766 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
19767 A list of key-value pairs that this dict should hold.
19768 Defaults to @samp{()}.
19773 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
19774 A list of passdb configurations, each one created by the
19775 @code{passdb-configuration} constructor.
19777 Available @code{passdb-configuration} fields are:
19779 @deftypevr {@code{passdb-configuration} parameter} string driver
19780 The driver that the passdb should use. Valid values include
19781 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
19783 Defaults to @samp{"pam"}.
19786 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
19787 Space separated list of arguments to the passdb driver.
19788 Defaults to @samp{""}.
19793 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
19794 List of userdb configurations, each one created by the
19795 @code{userdb-configuration} constructor.
19797 Available @code{userdb-configuration} fields are:
19799 @deftypevr {@code{userdb-configuration} parameter} string driver
19800 The driver that the userdb should use. Valid values include
19801 @samp{passwd} and @samp{static}.
19802 Defaults to @samp{"passwd"}.
19805 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
19806 Space separated list of arguments to the userdb driver.
19807 Defaults to @samp{""}.
19810 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
19811 Override fields from passwd.
19812 Defaults to @samp{()}.
19817 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
19818 Plug-in configuration, created by the @code{plugin-configuration}
19822 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
19823 List of namespaces. Each item in the list is created by the
19824 @code{namespace-configuration} constructor.
19826 Available @code{namespace-configuration} fields are:
19828 @deftypevr {@code{namespace-configuration} parameter} string name
19829 Name for this namespace.
19832 @deftypevr {@code{namespace-configuration} parameter} string type
19833 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
19834 Defaults to @samp{"private"}.
19837 @deftypevr {@code{namespace-configuration} parameter} string separator
19838 Hierarchy separator to use. You should use the same separator for
19839 all namespaces or some clients get confused. @samp{/} is usually a good
19840 one. The default however depends on the underlying mail storage
19842 Defaults to @samp{""}.
19845 @deftypevr {@code{namespace-configuration} parameter} string prefix
19846 Prefix required to access this namespace. This needs to be
19847 different for all namespaces. For example @samp{Public/}.
19848 Defaults to @samp{""}.
19851 @deftypevr {@code{namespace-configuration} parameter} string location
19852 Physical location of the mailbox. This is in the same format as
19853 mail_location, which is also the default for it.
19854 Defaults to @samp{""}.
19857 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
19858 There can be only one INBOX, and this setting defines which
19860 Defaults to @samp{#f}.
19863 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
19864 If namespace is hidden, it's not advertised to clients via NAMESPACE
19865 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
19866 useful when converting from another server with different namespaces
19867 which you want to deprecate but still keep working. For example you can
19868 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
19870 Defaults to @samp{#f}.
19873 @deftypevr {@code{namespace-configuration} parameter} boolean list?
19874 Show the mailboxes under this namespace with the LIST command. This
19875 makes the namespace visible for clients that do not support the NAMESPACE
19876 extension. The special @code{children} value lists child mailboxes, but
19877 hides the namespace prefix.
19878 Defaults to @samp{#t}.
19881 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
19882 Namespace handles its own subscriptions. If set to @code{#f}, the
19883 parent namespace handles them. The empty prefix should always have this
19885 Defaults to @samp{#t}.
19888 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
19889 List of predefined mailboxes in this namespace.
19890 Defaults to @samp{()}.
19892 Available @code{mailbox-configuration} fields are:
19894 @deftypevr {@code{mailbox-configuration} parameter} string name
19895 Name for this mailbox.
19898 @deftypevr {@code{mailbox-configuration} parameter} string auto
19899 @samp{create} will automatically create this mailbox.
19900 @samp{subscribe} will both create and subscribe to the mailbox.
19901 Defaults to @samp{"no"}.
19904 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
19905 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
19906 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
19907 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
19908 Defaults to @samp{()}.
19915 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
19916 Base directory where to store runtime data.
19917 Defaults to @samp{"/var/run/dovecot/"}.
19920 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
19921 Greeting message for clients.
19922 Defaults to @samp{"Dovecot ready."}.
19925 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
19926 List of trusted network ranges. Connections from these IPs are
19927 allowed to override their IP addresses and ports (for logging and for
19928 authentication checks). @samp{disable-plaintext-auth} is also ignored
19929 for these networks. Typically you would specify your IMAP proxy servers
19931 Defaults to @samp{()}.
19934 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
19935 List of login access check sockets (e.g.@: tcpwrap).
19936 Defaults to @samp{()}.
19939 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
19940 Show more verbose process titles (in ps). Currently shows user name
19941 and IP address. Useful for seeing who is actually using the IMAP
19942 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
19944 Defaults to @samp{#f}.
19947 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
19948 Should all processes be killed when Dovecot master process shuts down.
19949 Setting this to @code{#f} means that Dovecot can be upgraded without
19950 forcing existing client connections to close (although that could also
19951 be a problem if the upgrade is e.g.@: due to a security fix).
19952 Defaults to @samp{#t}.
19955 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
19956 If non-zero, run mail commands via this many connections to doveadm
19957 server, instead of running them directly in the same process.
19958 Defaults to @samp{0}.
19961 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
19962 UNIX socket or host:port used for connecting to doveadm server.
19963 Defaults to @samp{"doveadm-server"}.
19966 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
19967 List of environment variables that are preserved on Dovecot startup
19968 and passed down to all of its child processes. You can also give
19969 key=value pairs to always set specific settings.
19972 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
19973 Disable LOGIN command and all other plaintext authentications unless
19974 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
19975 matches the local IP (i.e.@: you're connecting from the same computer),
19976 the connection is considered secure and plaintext authentication is
19977 allowed. See also ssl=required setting.
19978 Defaults to @samp{#t}.
19981 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
19982 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
19983 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
19984 for caching to be used.
19985 Defaults to @samp{0}.
19988 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
19989 Time to live for cached data. After TTL expires the cached record
19990 is no longer used, *except* if the main database lookup returns internal
19991 failure. We also try to handle password changes automatically: If
19992 user's previous authentication was successful, but this one wasn't, the
19993 cache isn't used. For now this works only with plaintext
19995 Defaults to @samp{"1 hour"}.
19998 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
19999 TTL for negative hits (user not found, password mismatch).
20000 0 disables caching them completely.
20001 Defaults to @samp{"1 hour"}.
20004 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
20005 List of realms for SASL authentication mechanisms that need them.
20006 You can leave it empty if you don't want to support multiple realms.
20007 Many clients simply use the first one listed here, so keep the default
20009 Defaults to @samp{()}.
20012 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
20013 Default realm/domain to use if none was specified. This is used for
20014 both SASL realms and appending @@domain to username in plaintext
20016 Defaults to @samp{""}.
20019 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
20020 List of allowed characters in username. If the user-given username
20021 contains a character not listed in here, the login automatically fails.
20022 This is just an extra check to make sure user can't exploit any
20023 potential quote escaping vulnerabilities with SQL/LDAP databases. If
20024 you want to allow all characters, set this value to empty.
20025 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
20028 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
20029 Username character translations before it's looked up from
20030 databases. The value contains series of from -> to characters. For
20031 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
20032 translated to @samp{@@}.
20033 Defaults to @samp{""}.
20036 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
20037 Username formatting before it's looked up from databases. You can
20038 use the standard variables here, e.g.@: %Lu would lowercase the username,
20039 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
20040 change the @samp{@@} into @samp{-AT-}. This translation is done after
20041 @samp{auth-username-translation} changes.
20042 Defaults to @samp{"%Lu"}.
20045 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
20046 If you want to allow master users to log in by specifying the master
20047 username within the normal username string (i.e.@: not using SASL
20048 mechanism's support for it), you can specify the separator character
20049 here. The format is then <username><separator><master username>.
20050 UW-IMAP uses @samp{*} as the separator, so that could be a good
20052 Defaults to @samp{""}.
20055 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
20056 Username to use for users logging in with ANONYMOUS SASL
20058 Defaults to @samp{"anonymous"}.
20061 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
20062 Maximum number of dovecot-auth worker processes. They're used to
20063 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
20064 They're automatically created and destroyed as needed.
20065 Defaults to @samp{30}.
20068 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
20069 Host name to use in GSSAPI principal names. The default is to use
20070 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
20071 allow all keytab entries.
20072 Defaults to @samp{""}.
20075 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
20076 Kerberos keytab to use for the GSSAPI mechanism. Will use the
20077 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
20078 need to change the auth service to run as root to be able to read this
20080 Defaults to @samp{""}.
20083 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
20084 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
20085 and @samp{ntlm-auth} helper.
20086 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
20087 Defaults to @samp{#f}.
20090 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
20091 Path for Samba's @samp{ntlm-auth} helper binary.
20092 Defaults to @samp{"/usr/bin/ntlm_auth"}.
20095 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
20096 Time to delay before replying to failed authentications.
20097 Defaults to @samp{"2 secs"}.
20100 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
20101 Require a valid SSL client certificate or the authentication
20103 Defaults to @samp{#f}.
20106 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
20107 Take the username from client's SSL certificate, using
20108 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
20110 Defaults to @samp{#f}.
20113 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
20114 List of wanted authentication mechanisms. Supported mechanisms are:
20115 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
20116 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
20117 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
20118 @samp{disable-plaintext-auth} setting.
20121 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
20122 List of IPs or hostnames to all director servers, including ourself.
20123 Ports can be specified as ip:port. The default port is the same as what
20124 director service's @samp{inet-listener} is using.
20125 Defaults to @samp{()}.
20128 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
20129 List of IPs or hostnames to all backend mail servers. Ranges are
20130 allowed too, like 10.0.0.10-10.0.0.30.
20131 Defaults to @samp{()}.
20134 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
20135 How long to redirect users to a specific server after it no longer
20136 has any connections.
20137 Defaults to @samp{"15 min"}.
20140 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
20141 How the username is translated before being hashed. Useful values
20142 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
20143 are shared within domain.
20144 Defaults to @samp{"%Lu"}.
20147 @deftypevr {@code{dovecot-configuration} parameter} string log-path
20148 Log file to use for error messages. @samp{syslog} logs to syslog,
20149 @samp{/dev/stderr} logs to stderr.
20150 Defaults to @samp{"syslog"}.
20153 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
20154 Log file to use for informational messages. Defaults to
20156 Defaults to @samp{""}.
20159 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
20160 Log file to use for debug messages. Defaults to
20161 @samp{info-log-path}.
20162 Defaults to @samp{""}.
20165 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
20166 Syslog facility to use if you're logging to syslog. Usually if you
20167 don't want to use @samp{mail}, you'll use local0..local7. Also other
20168 standard facilities are supported.
20169 Defaults to @samp{"mail"}.
20172 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
20173 Log unsuccessful authentication attempts and the reasons why they
20175 Defaults to @samp{#f}.
20178 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
20179 In case of password mismatches, log the attempted password. Valid
20180 values are no, plain and sha1. sha1 can be useful for detecting brute
20181 force password attempts vs. user simply trying the same password over
20182 and over again. You can also truncate the value to n chars by appending
20183 ":n" (e.g.@: sha1:6).
20184 Defaults to @samp{"no"}.
20187 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
20188 Even more verbose logging for debugging purposes. Shows for example
20190 Defaults to @samp{#f}.
20193 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
20194 In case of password mismatches, log the passwords and used scheme so
20195 the problem can be debugged. Enabling this also enables
20197 Defaults to @samp{#f}.
20200 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
20201 Enable mail process debugging. This can help you figure out why
20202 Dovecot isn't finding your mails.
20203 Defaults to @samp{#f}.
20206 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
20207 Show protocol level SSL errors.
20208 Defaults to @samp{#f}.
20211 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
20212 Prefix for each line written to log file. % codes are in
20213 strftime(3) format.
20214 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
20217 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
20218 List of elements we want to log. The elements which have a
20219 non-empty variable value are joined together to form a comma-separated
20223 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
20224 Login log format. %s contains @samp{login-log-format-elements}
20225 string, %$ contains the data we want to log.
20226 Defaults to @samp{"%$: %s"}.
20229 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
20230 Log prefix for mail processes. See doc/wiki/Variables.txt for list
20231 of possible variables you can use.
20232 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
20235 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
20236 Format to use for logging mail deliveries. You can use variables:
20239 Delivery status message (e.g.@: @samp{saved to INBOX})
20251 Defaults to @samp{"msgid=%m: %$"}.
20254 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
20255 Location for users' mailboxes. The default is empty, which means
20256 that Dovecot tries to find the mailboxes automatically. This won't work
20257 if the user doesn't yet have any mail, so you should explicitly tell
20258 Dovecot the full location.
20260 If you're using mbox, giving a path to the INBOX
20261 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
20262 where the other mailboxes are kept. This is called the @emph{root mail
20263 directory}, and it must be the first path given in the
20264 @samp{mail-location} setting.
20266 There are a few special variables you can use, e.g.:
20272 user part in user@@domain, same as %u if there's no domain
20274 domain part in user@@domain, empty if there's no domain
20279 See doc/wiki/Variables.txt for full list. Some examples:
20281 @item maildir:~/Maildir
20282 @item mbox:~/mail:INBOX=/var/mail/%u
20283 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
20285 Defaults to @samp{""}.
20288 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
20289 System user and group used to access mails. If you use multiple,
20290 userdb can override these by returning uid or gid fields. You can use
20291 either numbers or names. <doc/wiki/UserIds.txt>.
20292 Defaults to @samp{""}.
20295 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
20297 Defaults to @samp{""}.
20300 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
20301 Group to enable temporarily for privileged operations. Currently
20302 this is used only with INBOX when either its initial creation or
20303 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
20305 Defaults to @samp{""}.
20308 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
20309 Grant access to these supplementary groups for mail processes.
20310 Typically these are used to set up access to shared mailboxes. Note
20311 that it may be dangerous to set these if users can create symlinks
20312 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
20313 could allow a user to delete others' mailboxes, or @code{ln -s
20314 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
20318 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
20319 Allow full file system access to clients. There's no access checks
20320 other than what the operating system does for the active UID/GID. It
20321 works with both maildir and mboxes, allowing you to prefix mailboxes
20322 names with e.g.@: @file{/path/} or @file{~user/}.
20323 Defaults to @samp{#f}.
20326 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
20327 Don't use @code{mmap()} at all. This is required if you store indexes to
20328 shared file systems (NFS or clustered file system).
20329 Defaults to @samp{#f}.
20332 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
20333 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
20334 supports @samp{O_EXCL} since version 3, so this should be safe to use
20335 nowadays by default.
20336 Defaults to @samp{#t}.
20339 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
20340 When to use fsync() or fdatasync() calls:
20343 Whenever necessary to avoid losing important data
20345 Useful with e.g.@: NFS when @code{write()}s are delayed
20347 Never use it (best performance, but crashes can lose data).
20349 Defaults to @samp{"optimized"}.
20352 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
20353 Mail storage exists in NFS. Set this to yes to make Dovecot flush
20354 NFS caches whenever needed. If you're using only a single mail server
20356 Defaults to @samp{#f}.
20359 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
20360 Mail index files also exist in NFS. Setting this to yes requires
20361 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
20362 Defaults to @samp{#f}.
20365 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
20366 Locking method for index files. Alternatives are fcntl, flock and
20367 dotlock. Dotlocking uses some tricks which may create more disk I/O
20368 than other locking methods. NFS users: flock doesn't work, remember to
20369 change @samp{mmap-disable}.
20370 Defaults to @samp{"fcntl"}.
20373 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
20374 Directory in which LDA/LMTP temporarily stores incoming mails >128
20376 Defaults to @samp{"/tmp"}.
20379 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
20380 Valid UID range for users. This is mostly to make sure that users can't
20381 log in as daemons or other system users. Note that denying root logins is
20382 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
20384 Defaults to @samp{500}.
20387 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
20389 Defaults to @samp{0}.
20392 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
20393 Valid GID range for users. Users having non-valid GID as primary group ID
20394 aren't allowed to log in. If user belongs to supplementary groups with
20395 non-valid GIDs, those groups are not set.
20396 Defaults to @samp{1}.
20399 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
20401 Defaults to @samp{0}.
20404 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
20405 Maximum allowed length for mail keyword name. It's only forced when
20406 trying to create new keywords.
20407 Defaults to @samp{50}.
20410 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
20411 List of directories under which chrooting is allowed for mail
20412 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
20413 too). This setting doesn't affect @samp{login-chroot}
20414 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
20415 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
20416 which local users can modify, that may lead to root exploit. Usually
20417 this should be done only if you don't allow shell access for users.
20418 <doc/wiki/Chrooting.txt>.
20419 Defaults to @samp{()}.
20422 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
20423 Default chroot directory for mail processes. This can be overridden
20424 for specific users in user database by giving @samp{/./} in user's home
20425 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
20426 there is no real need to do chrooting, Dovecot doesn't allow users to
20427 access files outside their mail directory anyway. If your home
20428 directories are prefixed with the chroot directory, append @samp{/.} to
20429 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
20430 Defaults to @samp{""}.
20433 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
20434 UNIX socket path to master authentication server to find users.
20435 This is used by imap (for shared users) and lda.
20436 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
20439 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
20440 Directory where to look up mail plugins.
20441 Defaults to @samp{"/usr/lib/dovecot"}.
20444 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
20445 List of plugins to load for all services. Plugins specific to IMAP,
20446 LDA, etc.@: are added to this list in their own .conf files.
20447 Defaults to @samp{()}.
20450 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
20451 The minimum number of mails in a mailbox before updates are done to
20452 cache file. This allows optimizing Dovecot's behavior to do less disk
20453 writes at the cost of more disk reads.
20454 Defaults to @samp{0}.
20457 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
20458 When IDLE command is running, mailbox is checked once in a while to
20459 see if there are any new mails or other changes. This setting defines
20460 the minimum time to wait between those checks. Dovecot can also use
20461 dnotify, inotify and kqueue to find out immediately when changes
20463 Defaults to @samp{"30 secs"}.
20466 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
20467 Save mails with CR+LF instead of plain LF. This makes sending those
20468 mails take less CPU, especially with sendfile() syscall with Linux and
20469 FreeBSD. But it also creates a bit more disk I/O which may just make it
20470 slower. Also note that if other software reads the mboxes/maildirs,
20471 they may handle the extra CRs wrong and cause problems.
20472 Defaults to @samp{#f}.
20475 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
20476 By default LIST command returns all entries in maildir beginning
20477 with a dot. Enabling this option makes Dovecot return only entries
20478 which are directories. This is done by stat()ing each entry, so it
20479 causes more disk I/O.
20480 (For systems setting struct @samp{dirent->d_type} this check is free
20481 and it's done always regardless of this setting).
20482 Defaults to @samp{#f}.
20485 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
20486 When copying a message, do it with hard links whenever possible.
20487 This makes the performance much better, and it's unlikely to have any
20489 Defaults to @samp{#t}.
20492 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
20493 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
20494 directory only when its mtime changes unexpectedly or when we can't find
20495 the mail otherwise.
20496 Defaults to @samp{#f}.
20499 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
20500 Which locking methods to use for locking mbox. There are four
20505 Create <mailbox>.lock file. This is the oldest and most NFS-safe
20506 solution. If you want to use /var/mail/ like directory, the users will
20507 need write access to that directory.
20509 Same as dotlock, but if it fails because of permissions or because there
20510 isn't enough disk space, just skip it.
20512 Use this if possible. Works with NFS too if lockd is used.
20514 May not exist in all systems. Doesn't work with NFS.
20516 May not exist in all systems. Doesn't work with NFS.
20519 You can use multiple locking methods; if you do the order they're declared
20520 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
20521 locking methods as well. Some operating systems don't allow using some of
20522 them simultaneously.
20525 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
20529 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
20530 Maximum time to wait for lock (all of them) before aborting.
20531 Defaults to @samp{"5 mins"}.
20534 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
20535 If dotlock exists but the mailbox isn't modified in any way,
20536 override the lock file after this much time.
20537 Defaults to @samp{"2 mins"}.
20540 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
20541 When mbox changes unexpectedly we have to fully read it to find out
20542 what changed. If the mbox is large this can take a long time. Since
20543 the change is usually just a newly appended mail, it'd be faster to
20544 simply read the new mails. If this setting is enabled, Dovecot does
20545 this but still safely fallbacks to re-reading the whole mbox file
20546 whenever something in mbox isn't how it's expected to be. The only real
20547 downside to this setting is that if some other MUA changes message
20548 flags, Dovecot doesn't notice it immediately. Note that a full sync is
20549 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
20550 Defaults to @samp{#t}.
20553 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
20554 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
20555 EXAMINE, EXPUNGE or CHECK commands. If this is set,
20556 @samp{mbox-dirty-syncs} is ignored.
20557 Defaults to @samp{#f}.
20560 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
20561 Delay writing mbox headers until doing a full write sync (EXPUNGE
20562 and CHECK commands and when closing the mailbox). This is especially
20563 useful for POP3 where clients often delete all mails. The downside is
20564 that our changes aren't immediately visible to other MUAs.
20565 Defaults to @samp{#t}.
20568 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
20569 If mbox size is smaller than this (e.g.@: 100k), don't write index
20570 files. If an index file already exists it's still read, just not
20572 Defaults to @samp{0}.
20575 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
20576 Maximum dbox file size until it's rotated.
20577 Defaults to @samp{10000000}.
20580 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
20581 Maximum dbox file age until it's rotated. Typically in days. Day
20582 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
20584 Defaults to @samp{"1d"}.
20587 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
20588 When creating new mdbox files, immediately preallocate their size to
20589 @samp{mdbox-rotate-size}. This setting currently works only in Linux
20590 with some file systems (ext4, xfs).
20591 Defaults to @samp{#f}.
20594 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
20595 sdbox and mdbox support saving mail attachments to external files,
20596 which also allows single instance storage for them. Other backends
20597 don't support this for now.
20599 WARNING: This feature hasn't been tested much yet. Use at your own risk.
20601 Directory root where to store mail attachments. Disabled, if empty.
20602 Defaults to @samp{""}.
20605 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
20606 Attachments smaller than this aren't saved externally. It's also
20607 possible to write a plugin to disable saving specific attachments
20609 Defaults to @samp{128000}.
20612 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
20613 File system backend to use for saving attachments:
20616 No SiS done by Dovecot (but this might help FS's own deduplication)
20618 SiS with immediate byte-by-byte comparison during saving
20619 @item sis-queue posix
20620 SiS with delayed comparison and deduplication.
20622 Defaults to @samp{"sis posix"}.
20625 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
20626 Hash format to use in attachment filenames. You can add any text and
20627 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
20628 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
20629 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
20630 Defaults to @samp{"%@{sha1@}"}.
20633 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
20635 Defaults to @samp{100}.
20638 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
20640 Defaults to @samp{1000}.
20643 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
20644 Default VSZ (virtual memory size) limit for service processes.
20645 This is mainly intended to catch and kill processes that leak memory
20646 before they eat up everything.
20647 Defaults to @samp{256000000}.
20650 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
20651 Login user is internally used by login processes. This is the most
20652 untrusted user in Dovecot system. It shouldn't have access to anything
20654 Defaults to @samp{"dovenull"}.
20657 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
20658 Internal user is used by unprivileged processes. It should be
20659 separate from login user, so that login processes can't disturb other
20661 Defaults to @samp{"dovecot"}.
20664 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
20665 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
20666 Defaults to @samp{"required"}.
20669 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
20670 PEM encoded X.509 SSL/TLS certificate (public key).
20671 Defaults to @samp{"</etc/dovecot/default.pem"}.
20674 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
20675 PEM encoded SSL/TLS private key. The key is opened before
20676 dropping root privileges, so keep the key file unreadable by anyone but
20678 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
20681 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
20682 If key file is password protected, give the password here.
20683 Alternatively give it when starting dovecot with -p parameter. Since
20684 this file is often world-readable, you may want to place this setting
20685 instead to a different.
20686 Defaults to @samp{""}.
20689 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
20690 PEM encoded trusted certificate authority. Set this only if you
20691 intend to use @samp{ssl-verify-client-cert? #t}. The file should
20692 contain the CA certificate(s) followed by the matching
20693 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
20694 Defaults to @samp{""}.
20697 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
20698 Require that CRL check succeeds for client certificates.
20699 Defaults to @samp{#t}.
20702 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
20703 Request client to send a certificate. If you also want to require
20704 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
20705 Defaults to @samp{#f}.
20708 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
20709 Which field from certificate to use for username. commonName and
20710 x500UniqueIdentifier are the usual choices. You'll also need to set
20711 @samp{auth-ssl-username-from-cert? #t}.
20712 Defaults to @samp{"commonName"}.
20715 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
20716 Minimum SSL protocol version to accept.
20717 Defaults to @samp{"TLSv1"}.
20720 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
20721 SSL ciphers to use.
20722 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
20725 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
20726 SSL crypto device to use, for valid values run "openssl engine".
20727 Defaults to @samp{""}.
20730 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
20731 Address to use when sending rejection mails.
20732 %d expands to recipient domain.
20733 Defaults to @samp{"postmaster@@%d"}.
20736 @deftypevr {@code{dovecot-configuration} parameter} string hostname
20737 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
20738 and in LMTP replies. Default is the system's real hostname@@domain.
20739 Defaults to @samp{""}.
20742 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
20743 If user is over quota, return with temporary failure instead of
20745 Defaults to @samp{#f}.
20748 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
20749 Binary to use for sending mails.
20750 Defaults to @samp{"/usr/sbin/sendmail"}.
20753 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
20754 If non-empty, send mails via this SMTP host[:port] instead of
20756 Defaults to @samp{""}.
20759 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
20760 Subject: header to use for rejection mails. You can use the same
20761 variables as for @samp{rejection-reason} below.
20762 Defaults to @samp{"Rejected: %s"}.
20765 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
20766 Human readable error message for rejection mails. You can use
20779 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
20782 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
20783 Delimiter character between local-part and detail in email
20785 Defaults to @samp{"+"}.
20788 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
20789 Header where the original recipient address (SMTP's RCPT TO:
20790 address) is taken from if not available elsewhere. With dovecot-lda -a
20791 parameter overrides this. A commonly used header for this is
20793 Defaults to @samp{""}.
20796 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
20797 Should saving a mail to a nonexistent mailbox automatically create
20799 Defaults to @samp{#f}.
20802 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
20803 Should automatically created mailboxes be also automatically
20805 Defaults to @samp{#f}.
20808 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
20809 Maximum IMAP command line length. Some clients generate very long
20810 command lines with huge mailboxes, so you may need to raise this if you
20811 get "Too long argument" or "IMAP command line too large" errors
20813 Defaults to @samp{64000}.
20816 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
20817 IMAP logout format string:
20820 total number of bytes read from client
20822 total number of bytes sent to client.
20824 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
20825 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@}"}.
20828 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
20829 Override the IMAP CAPABILITY response. If the value begins with '+',
20830 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
20831 Defaults to @samp{""}.
20834 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
20835 How long to wait between "OK Still here" notifications when client
20837 Defaults to @samp{"2 mins"}.
20840 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
20841 ID field names and values to send to clients. Using * as the value
20842 makes Dovecot use the default value. The following fields have default
20843 values currently: name, version, os, os-version, support-url,
20845 Defaults to @samp{""}.
20848 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
20849 ID fields sent by client to log. * means everything.
20850 Defaults to @samp{""}.
20853 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
20854 Workarounds for various client bugs:
20857 @item delay-newmail
20858 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
20859 CHECK commands. Some clients ignore them otherwise, for example OSX
20860 Mail (<v2.1). Outlook Express breaks more badly though, without this it
20861 may show user "Message no longer in server" errors. Note that OE6
20862 still breaks even with this workaround if synchronization is set to
20865 @item tb-extra-mailbox-sep
20866 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
20867 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
20868 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
20870 @item tb-lsub-flags
20871 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
20872 This makes Thunderbird realize they aren't selectable and show them
20873 greyed out, instead of only later giving "not selectable" popup error.
20875 Defaults to @samp{()}.
20878 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
20879 Host allowed in URLAUTH URLs sent by client. "*" allows all.
20880 Defaults to @samp{""}.
20884 Whew! Lots of configuration options. The nice thing about it though is
20885 that Guix has a complete interface to Dovecot's configuration
20886 language. This allows not only a nice way to declare configurations,
20887 but also offers reflective capabilities as well: users can write code to
20888 inspect and transform configurations from within Scheme.
20890 However, it could be that you just want to get a @code{dovecot.conf} up
20891 and running. In that case, you can pass an
20892 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
20893 @code{dovecot-service}. As its name indicates, an opaque configuration
20894 does not have easy reflective capabilities.
20896 Available @code{opaque-dovecot-configuration} fields are:
20898 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
20899 The dovecot package.
20902 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
20903 The contents of the @code{dovecot.conf}, as a string.
20906 For example, if your @code{dovecot.conf} is just the empty string, you
20907 could instantiate a dovecot service like this:
20910 (dovecot-service #:config
20911 (opaque-dovecot-configuration
20915 @subsubheading OpenSMTPD Service
20917 @deffn {Scheme Variable} opensmtpd-service-type
20918 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
20919 service, whose value should be an @code{opensmtpd-configuration} object
20920 as in this example:
20923 (service opensmtpd-service-type
20924 (opensmtpd-configuration
20925 (config-file (local-file "./my-smtpd.conf"))))
20929 @deftp {Data Type} opensmtpd-configuration
20930 Data type representing the configuration of opensmtpd.
20933 @item @code{package} (default: @var{opensmtpd})
20934 Package object of the OpenSMTPD SMTP server.
20936 @item @code{config-file} (default: @code{%default-opensmtpd-file})
20937 File-like object of the OpenSMTPD configuration file to use. By default
20938 it listens on the loopback network interface, and allows for mail from
20939 users and daemons on the local machine, as well as permitting email to
20940 remote servers. Run @command{man smtpd.conf} for more information.
20945 @subsubheading Exim Service
20947 @cindex mail transfer agent (MTA)
20948 @cindex MTA (mail transfer agent)
20951 @deffn {Scheme Variable} exim-service-type
20952 This is the type of the @uref{https://exim.org, Exim} mail transfer
20953 agent (MTA), whose value should be an @code{exim-configuration} object
20954 as in this example:
20957 (service exim-service-type
20958 (exim-configuration
20959 (config-file (local-file "./my-exim.conf"))))
20963 In order to use an @code{exim-service-type} service you must also have a
20964 @code{mail-aliases-service-type} service present in your
20965 @code{operating-system} (even if it has no aliases).
20967 @deftp {Data Type} exim-configuration
20968 Data type representing the configuration of exim.
20971 @item @code{package} (default: @var{exim})
20972 Package object of the Exim server.
20974 @item @code{config-file} (default: @code{#f})
20975 File-like object of the Exim configuration file to use. If its value is
20976 @code{#f} then use the default configuration file from the package
20977 provided in @code{package}. The resulting configuration file is loaded
20978 after setting the @code{exim_user} and @code{exim_group} configuration
20984 @subsubheading Getmail service
20989 @deffn {Scheme Variable} getmail-service-type
20990 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
20991 mail retriever, whose value should be an @code{getmail-configuration}.
20994 Available @code{getmail-configuration} fields are:
20996 @deftypevr {@code{getmail-configuration} parameter} symbol name
20997 A symbol to identify the getmail service.
20999 Defaults to @samp{"unset"}.
21003 @deftypevr {@code{getmail-configuration} parameter} package package
21004 The getmail package to use.
21008 @deftypevr {@code{getmail-configuration} parameter} string user
21009 The user to run getmail as.
21011 Defaults to @samp{"getmail"}.
21015 @deftypevr {@code{getmail-configuration} parameter} string group
21016 The group to run getmail as.
21018 Defaults to @samp{"getmail"}.
21022 @deftypevr {@code{getmail-configuration} parameter} string directory
21023 The getmail directory to use.
21025 Defaults to @samp{"/var/lib/getmail/default"}.
21029 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
21030 The getmail configuration file to use.
21032 Available @code{getmail-configuration-file} fields are:
21034 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
21035 What mail account to retrieve mail from, and how to access that account.
21037 Available @code{getmail-retriever-configuration} fields are:
21039 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
21040 The type of mail retriever to use. Valid values include @samp{passwd}
21043 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
21047 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
21048 Username to login to the mail server with.
21050 Defaults to @samp{unset}.
21054 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
21055 Username to login to the mail server with.
21057 Defaults to @samp{unset}.
21061 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
21062 Port number to connect to.
21064 Defaults to @samp{#f}.
21068 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
21069 Override fields from passwd.
21071 Defaults to @samp{""}.
21075 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
21076 Override fields from passwd.
21078 Defaults to @samp{()}.
21082 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
21083 PEM-formatted key file to use for the TLS negotiation.
21085 Defaults to @samp{""}.
21089 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
21090 PEM-formatted certificate file to use for the TLS negotiation.
21092 Defaults to @samp{""}.
21096 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
21097 CA certificates to use.
21099 Defaults to @samp{""}.
21103 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
21104 Extra retriever parameters.
21106 Defaults to @samp{()}.
21112 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
21113 What to do with retrieved messages.
21115 Available @code{getmail-destination-configuration} fields are:
21117 @deftypevr {@code{getmail-destination-configuration} parameter} string type
21118 The type of mail destination. Valid values include @samp{Maildir},
21119 @samp{Mboxrd} and @samp{MDA_external}.
21121 Defaults to @samp{unset}.
21125 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
21126 The path option for the mail destination. The behaviour depends on the
21129 Defaults to @samp{""}.
21133 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
21134 Extra destination parameters
21136 Defaults to @samp{()}.
21142 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
21145 Available @code{getmail-options-configuration} fields are:
21147 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
21148 If set to @samp{0}, getmail will only print warnings and errors. A
21149 value of @samp{1} means that messages will be printed about retrieving
21150 and deleting messages. If set to @samp{2}, getmail will print messages
21151 about each of it's actions.
21153 Defaults to @samp{1}.
21157 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
21158 If true, getmail will retrieve all available messages. Otherwise it
21159 will only retrieve messages it hasn't seen previously.
21161 Defaults to @samp{#t}.
21165 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
21166 If set to true, messages will be deleted from the server after
21167 retrieving and successfully delivering them. Otherwise, messages will
21168 be left on the server.
21170 Defaults to @samp{#f}.
21174 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
21175 Getmail will delete messages this number of days after seeing them, if
21176 they have been delivered. This means messages will be left on the
21177 server this number of days after delivering them. A value of @samp{0}
21178 disabled this feature.
21180 Defaults to @samp{0}.
21184 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
21185 Delete messages larger than this of bytes after retrieving them, even if
21186 the delete and delete-after options are disabled. A value of @samp{0}
21187 disables this feature.
21189 Defaults to @samp{0}.
21193 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
21194 Retrieve messages totalling up to this number of bytes before closing
21195 the session with the server. A value of @samp{0} disables this feature.
21197 Defaults to @samp{0}.
21201 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
21202 Don't retrieve messages larger than this number of bytes. A value of
21203 @samp{0} disables this feature.
21205 Defaults to @samp{0}.
21209 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
21210 If true, getmail will add a Delivered-To header to messages.
21212 Defaults to @samp{#t}.
21216 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
21217 If set, getmail adds a Received header to the messages.
21219 Defaults to @samp{#t}.
21223 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
21224 Getmail will record a log of its actions to the named file. A value of
21225 @samp{""} disables this feature.
21227 Defaults to @samp{""}.
21231 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
21232 If true, getmail will record a log of its actions using the system
21235 Defaults to @samp{#f}.
21239 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
21240 If true, getmail will log information about messages not retrieved and
21241 the reason for not retrieving them, as well as starting and ending
21244 Defaults to @samp{#f}.
21248 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
21249 Extra options to include.
21251 Defaults to @samp{()}.
21259 @deftypevr {@code{getmail-configuration} parameter} list idle
21260 A list of mailboxes that getmail should wait on the server for new mail
21261 notifications. This depends on the server supporting the IDLE
21264 Defaults to @samp{()}.
21268 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
21269 Environment variables to set for getmail.
21271 Defaults to @samp{()}.
21275 @subsubheading Mail Aliases Service
21277 @cindex email aliases
21278 @cindex aliases, for email addresses
21280 @deffn {Scheme Variable} mail-aliases-service-type
21281 This is the type of the service which provides @code{/etc/aliases},
21282 specifying how to deliver mail to users on this system.
21285 (service mail-aliases-service-type
21286 '(("postmaster" "bob")
21287 ("bob" "bob@@example.com" "bob@@example2.com")))
21291 The configuration for a @code{mail-aliases-service-type} service is an
21292 association list denoting how to deliver mail that comes to this
21293 system. Each entry is of the form @code{(alias addresses ...)}, with
21294 @code{alias} specifying the local alias and @code{addresses} specifying
21295 where to deliver this user's mail.
21297 The aliases aren't required to exist as users on the local system. In
21298 the above example, there doesn't need to be a @code{postmaster} entry in
21299 the @code{operating-system}'s @code{user-accounts} in order to deliver
21300 the @code{postmaster} mail to @code{bob} (which subsequently would
21301 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
21303 @subsubheading GNU Mailutils IMAP4 Daemon
21304 @cindex GNU Mailutils IMAP4 Daemon
21306 @deffn {Scheme Variable} imap4d-service-type
21307 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
21308 mailutils, GNU Mailutils Manual}), whose value should be an
21309 @code{imap4d-configuration} object as in this example:
21312 (service imap4d-service-type
21313 (imap4d-configuration
21314 (config-file (local-file "imap4d.conf"))))
21318 @deftp {Data Type} imap4d-configuration
21319 Data type representing the configuration of @command{imap4d}.
21322 @item @code{package} (default: @code{mailutils})
21323 The package that provides @command{imap4d}.
21325 @item @code{config-file} (default: @code{%default-imap4d-config-file})
21326 File-like object of the configuration file to use, by default it will listen
21327 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
21328 Mailutils Manual}, for details.
21333 @subsubheading Radicale Service
21337 @deffn {Scheme Variable} radicale-service-type
21338 This is the type of the @uref{https://radicale.org, Radicale} CalDAV/CardDAV
21339 server whose value should be a @code{radicale-configuration}.
21342 @deftp {Data Type} radicale-configuration
21343 Data type representing the configuration of @command{radicale}.
21346 @item @code{package} (default: @code{radicale})
21347 The package that provides @command{radicale}.
21349 @item @code{config-file} (default: @code{%default-radicale-config-file})
21350 File-like object of the configuration file to use, by default it will listen
21351 on TCP port 5232 of @code{localhost} and use the @code{htpasswd} file at
21352 @file{/var/lib/radicale/users} with no (@code{plain}) encryption.
21357 @node Messaging Services
21358 @subsection Messaging Services
21363 The @code{(gnu services messaging)} module provides Guix service
21364 definitions for messaging services. Currently it provides the following
21367 @subsubheading Prosody Service
21369 @deffn {Scheme Variable} prosody-service-type
21370 This is the type for the @uref{https://prosody.im, Prosody XMPP
21371 communication server}. Its value must be a @code{prosody-configuration}
21372 record as in this example:
21375 (service prosody-service-type
21376 (prosody-configuration
21377 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
21380 (int-component-configuration
21381 (hostname "conference.example.net")
21383 (mod-muc (mod-muc-configuration)))))
21386 (virtualhost-configuration
21387 (domain "example.net"))))))
21390 See below for details about @code{prosody-configuration}.
21394 By default, Prosody does not need much configuration. Only one
21395 @code{virtualhosts} field is needed: it specifies the domain you wish
21398 You can perform various sanity checks on the generated configuration
21399 with the @code{prosodyctl check} command.
21401 Prosodyctl will also help you to import certificates from the
21402 @code{letsencrypt} directory so that the @code{prosody} user can access
21403 them. See @url{https://prosody.im/doc/letsencrypt}.
21406 prosodyctl --root cert import /etc/letsencrypt/live
21409 The available configuration parameters follow. Each parameter
21410 definition is preceded by its type; for example, @samp{string-list foo}
21411 indicates that the @code{foo} parameter should be specified as a list of
21412 strings. Types starting with @code{maybe-} denote parameters that won't
21413 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
21415 There is also a way to specify the configuration as a string, if you
21416 have an old @code{prosody.cfg.lua} file that you want to port over from
21417 some other system; see the end for more details.
21419 The @code{file-object} type designates either a file-like object
21420 (@pxref{G-Expressions, file-like objects}) or a file name.
21422 @c The following documentation was initially generated by
21423 @c (generate-documentation) in (gnu services messaging). Manually maintained
21424 @c documentation is better, so we shouldn't hesitate to edit below as
21425 @c needed. However if the change you want to make to this documentation
21426 @c can be done in an automated way, it's probably easier to change
21427 @c (generate-documentation) than to make it below and have to deal with
21428 @c the churn as Prosody updates.
21430 Available @code{prosody-configuration} fields are:
21432 @deftypevr {@code{prosody-configuration} parameter} package prosody
21433 The Prosody package.
21436 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
21437 Location of the Prosody data storage directory. See
21438 @url{https://prosody.im/doc/configure}.
21439 Defaults to @samp{"/var/lib/prosody"}.
21442 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
21443 Additional plugin directories. They are searched in all the specified
21444 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
21445 Defaults to @samp{()}.
21448 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
21449 Every virtual host and component needs a certificate so that clients and
21450 servers can securely verify its identity. Prosody will automatically load
21451 certificates/keys from the directory specified here.
21452 Defaults to @samp{"/etc/prosody/certs"}.
21455 @deftypevr {@code{prosody-configuration} parameter} string-list admins
21456 This is a list of accounts that are admins for the server. Note that you
21457 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
21458 @url{https://prosody.im/doc/creating_accounts}.
21459 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
21460 Defaults to @samp{()}.
21463 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
21464 Enable use of libevent for better performance under high load. See
21465 @url{https://prosody.im/doc/libevent}.
21466 Defaults to @samp{#f}.
21469 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
21470 This is the list of modules Prosody will load on startup. It looks for
21471 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
21472 Documentation on modules can be found at:
21473 @url{https://prosody.im/doc/modules}.
21474 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
21477 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
21478 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
21479 should you want to disable them then add them to this list.
21480 Defaults to @samp{()}.
21483 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
21484 Path to a text file where the shared groups are defined. If this path is
21485 empty then @samp{mod_groups} does nothing. See
21486 @url{https://prosody.im/doc/modules/mod_groups}.
21487 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
21490 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
21491 Disable account creation by default, for security. See
21492 @url{https://prosody.im/doc/creating_accounts}.
21493 Defaults to @samp{#f}.
21496 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
21497 These are the SSL/TLS-related settings. Most of them are disabled so to
21498 use Prosody's defaults. If you do not completely understand these options, do
21499 not add them to your config, it is easy to lower the security of your server
21500 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
21502 Available @code{ssl-configuration} fields are:
21504 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
21505 This determines what handshake to use.
21508 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
21509 Path to your private key file.
21512 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
21513 Path to your certificate file.
21516 @deftypevr {@code{ssl-configuration} parameter} file-object capath
21517 Path to directory containing root certificates that you wish Prosody to
21518 trust when verifying the certificates of remote servers.
21519 Defaults to @samp{"/etc/ssl/certs"}.
21522 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
21523 Path to a file containing root certificates that you wish Prosody to trust.
21524 Similar to @code{capath} but with all certificates concatenated together.
21527 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
21528 A list of verification options (these mostly map to OpenSSL's
21529 @code{set_verify()} flags).
21532 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
21533 A list of general options relating to SSL/TLS. These map to OpenSSL's
21534 @code{set_options()}. For a full list of options available in LuaSec, see the
21538 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
21539 How long a chain of certificate authorities to check when looking for a
21540 trusted root certificate.
21543 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
21544 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
21545 clients, and in what order.
21548 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
21549 A path to a file containing parameters for Diffie-Hellman key exchange. You
21550 can create such a file with:
21551 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
21554 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
21555 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
21556 @samp{"secp384r1"}.
21559 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
21560 A list of ``extra'' verification options.
21563 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
21564 Password for encrypted private keys.
21569 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
21570 Whether to force all client-to-server connections to be encrypted or not.
21571 See @url{https://prosody.im/doc/modules/mod_tls}.
21572 Defaults to @samp{#f}.
21575 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
21576 Set of mechanisms that will never be offered. See
21577 @url{https://prosody.im/doc/modules/mod_saslauth}.
21578 Defaults to @samp{("DIGEST-MD5")}.
21581 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
21582 Whether to force all server-to-server connections to be encrypted or not.
21583 See @url{https://prosody.im/doc/modules/mod_tls}.
21584 Defaults to @samp{#f}.
21587 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
21588 Whether to require encryption and certificate authentication. This
21589 provides ideal security, but requires servers you communicate with to support
21590 encryption AND present valid, trusted certificates. See
21591 @url{https://prosody.im/doc/s2s#security}.
21592 Defaults to @samp{#f}.
21595 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
21596 Many servers don't support encryption or have invalid or self-signed
21597 certificates. You can list domains here that will not be required to
21598 authenticate using certificates. They will be authenticated using DNS. See
21599 @url{https://prosody.im/doc/s2s#security}.
21600 Defaults to @samp{()}.
21603 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
21604 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
21605 valid certificates for some domains by specifying a list here. See
21606 @url{https://prosody.im/doc/s2s#security}.
21607 Defaults to @samp{()}.
21610 @deftypevr {@code{prosody-configuration} parameter} string authentication
21611 Select the authentication backend to use. The default provider stores
21612 passwords in plaintext and uses Prosody's configured data storage to store the
21613 authentication data. If you do not trust your server please see
21614 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
21615 about using the hashed backend. See also
21616 @url{https://prosody.im/doc/authentication}
21617 Defaults to @samp{"internal_plain"}.
21620 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
21621 Set logging options. Advanced logging configuration is not yet supported
21622 by the Prosody service. See @url{https://prosody.im/doc/logging}.
21623 Defaults to @samp{"*syslog"}.
21626 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
21627 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
21628 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
21631 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
21632 Maximum allowed size of the HTTP body (in bytes).
21635 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
21636 Some modules expose their own URL in various ways. This URL is built
21637 from the protocol, host and port used. If Prosody sits behind a proxy, the
21638 public URL will be @code{http-external-url} instead. See
21639 @url{https://prosody.im/doc/http#external_url}.
21642 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
21643 A host in Prosody is a domain on which user accounts can be created. For
21644 example if you want your users to have addresses like
21645 @samp{"john.smith@@example.com"} then you need to add a host
21646 @samp{"example.com"}. All options in this list will apply only to this host.
21648 Note: the name @emph{virtual} host is used in configuration to avoid confusion with
21649 the actual physical host that Prosody is installed on. A single Prosody
21650 instance can serve many domains, each one defined as a VirtualHost entry in
21651 Prosody's configuration. Conversely a server that hosts a single domain would
21652 have just one VirtualHost entry.
21654 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
21656 Available @code{virtualhost-configuration} fields are:
21658 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:
21659 @deftypevr {@code{virtualhost-configuration} parameter} string domain
21660 Domain you wish Prosody to serve.
21665 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
21666 Components are extra services on a server which are available to clients,
21667 usually on a subdomain of the main server (such as
21668 @samp{"mycomponent.example.com"}). Example components might be chatroom
21669 servers, user directories, or gateways to other protocols.
21671 Internal components are implemented with Prosody-specific plugins. To add an
21672 internal component, you simply fill the hostname field, and the plugin you wish
21673 to use for the component.
21675 See @url{https://prosody.im/doc/components}.
21676 Defaults to @samp{()}.
21678 Available @code{int-component-configuration} fields are:
21680 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:
21681 @deftypevr {@code{int-component-configuration} parameter} string hostname
21682 Hostname of the component.
21685 @deftypevr {@code{int-component-configuration} parameter} string plugin
21686 Plugin you wish to use for the component.
21689 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
21690 Multi-user chat (MUC) is Prosody's module for allowing you to create
21691 hosted chatrooms/conferences for XMPP users.
21693 General information on setting up and using multi-user chatrooms can be found
21694 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
21695 which you should read if you are new to XMPP chatrooms.
21697 See also @url{https://prosody.im/doc/modules/mod_muc}.
21699 Available @code{mod-muc-configuration} fields are:
21701 @deftypevr {@code{mod-muc-configuration} parameter} string name
21702 The name to return in service discovery responses.
21703 Defaults to @samp{"Prosody Chatrooms"}.
21706 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
21707 If @samp{#t}, this will only allow admins to create new chatrooms.
21708 Otherwise anyone can create a room. The value @samp{"local"} restricts room
21709 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
21710 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
21711 restricts to service administrators only.
21712 Defaults to @samp{#f}.
21715 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
21716 Maximum number of history messages that will be sent to the member that has
21717 just joined the room.
21718 Defaults to @samp{20}.
21725 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
21726 External components use XEP-0114, which most standalone components
21727 support. To add an external component, you simply fill the hostname field. See
21728 @url{https://prosody.im/doc/components}.
21729 Defaults to @samp{()}.
21731 Available @code{ext-component-configuration} fields are:
21733 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:
21734 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
21735 Password which the component will use to log in.
21738 @deftypevr {@code{ext-component-configuration} parameter} string hostname
21739 Hostname of the component.
21744 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
21745 Port(s) Prosody listens on for component connections.
21746 Defaults to @samp{(5347)}.
21749 @deftypevr {@code{prosody-configuration} parameter} string component-interface
21750 Interface Prosody listens on for component connections.
21751 Defaults to @samp{"127.0.0.1"}.
21754 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
21755 Raw content that will be added to the configuration file.
21758 It could be that you just want to get a @code{prosody.cfg.lua}
21759 up and running. In that case, you can pass an
21760 @code{opaque-prosody-configuration} record as the value of
21761 @code{prosody-service-type}. As its name indicates, an opaque configuration
21762 does not have easy reflective capabilities.
21763 Available @code{opaque-prosody-configuration} fields are:
21765 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
21766 The prosody package.
21769 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
21770 The contents of the @code{prosody.cfg.lua} to use.
21773 For example, if your @code{prosody.cfg.lua} is just the empty
21774 string, you could instantiate a prosody service like this:
21777 (service prosody-service-type
21778 (opaque-prosody-configuration
21779 (prosody.cfg.lua "")))
21782 @c end of Prosody auto-generated documentation
21784 @subsubheading BitlBee Service
21786 @cindex IRC (Internet Relay Chat)
21787 @cindex IRC gateway
21788 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
21789 interface to a variety of messaging protocols such as XMPP.
21791 @defvr {Scheme Variable} bitlbee-service-type
21792 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
21793 gateway daemon. Its value is a @code{bitlbee-configuration} (see
21796 To have BitlBee listen on port 6667 on localhost, add this line to your
21800 (service bitlbee-service-type)
21804 @deftp {Data Type} bitlbee-configuration
21805 This is the configuration for BitlBee, with the following fields:
21808 @item @code{interface} (default: @code{"127.0.0.1"})
21809 @itemx @code{port} (default: @code{6667})
21810 Listen on the network interface corresponding to the IP address
21811 specified in @var{interface}, on @var{port}.
21813 When @var{interface} is @code{127.0.0.1}, only local clients can
21814 connect; when it is @code{0.0.0.0}, connections can come from any
21815 networking interface.
21817 @item @code{bitlbee} (default: @code{bitlbee})
21818 The BitlBee package to use.
21820 @item @code{plugins} (default: @code{'()})
21821 List of plugin packages to use---e.g., @code{bitlbee-discord}.
21823 @item @code{extra-settings} (default: @code{""})
21824 Configuration snippet added as-is to the BitlBee configuration file.
21828 @subsubheading Quassel Service
21830 @cindex IRC (Internet Relay Chat)
21831 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
21832 meaning that one or more clients can attach to and detach from the
21835 @defvr {Scheme Variable} quassel-service-type
21836 This is the service type for the @url{https://quassel-irc.org/,Quassel}
21837 IRC backend daemon. Its value is a @code{quassel-configuration}
21841 @deftp {Data Type} quassel-configuration
21842 This is the configuration for Quassel, with the following fields:
21845 @item @code{quassel} (default: @code{quassel})
21846 The Quassel package to use.
21848 @item @code{interface} (default: @code{"::,0.0.0.0"})
21849 @item @code{port} (default: @code{4242})
21850 Listen on the network interface(s) corresponding to the IPv4 or IPv6
21851 interfaces specified in the comma delimited @var{interface}, on
21854 @item @code{loglevel} (default: @code{"Info"})
21855 The level of logging desired. Accepted values are Debug, Info, Warning
21860 @node Telephony Services
21861 @subsection Telephony Services
21863 @cindex Murmur (VoIP server)
21864 @cindex VoIP server
21865 This section describes how to set up and run a Murmur server. Murmur is
21866 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
21869 @deftp {Data Type} murmur-configuration
21870 The service type for the Murmur server. An example configuration can
21874 (service murmur-service-type
21875 (murmur-configuration
21877 "Welcome to this Mumble server running on Guix!")
21878 (cert-required? #t) ;disallow text password logins
21879 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
21880 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
21883 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
21884 password with the command that is printed during the activation phase.
21886 It is recommended to register a normal Mumble user account
21887 and grant it admin or moderator rights.
21888 You can use the @code{mumble} client to
21889 login as new normal user, register yourself, and log out.
21890 For the next step login with the name @code{SuperUser} use
21891 the @code{SuperUser} password that you set previously,
21892 and grant your newly registered mumble user administrator or moderator
21893 rights and create some channels.
21895 Available @code{murmur-configuration} fields are:
21898 @item @code{package} (default: @code{mumble})
21899 Package that contains @code{bin/murmurd}.
21901 @item @code{user} (default: @code{"murmur"})
21902 User who will run the Murmur server.
21904 @item @code{group} (default: @code{"murmur"})
21905 Group of the user who will run the murmur server.
21907 @item @code{port} (default: @code{64738})
21908 Port on which the server will listen.
21910 @item @code{welcome-text} (default: @code{""})
21911 Welcome text sent to clients when they connect.
21913 @item @code{server-password} (default: @code{""})
21914 Password the clients have to enter in order to connect.
21916 @item @code{max-users} (default: @code{100})
21917 Maximum of users that can be connected to the server at once.
21919 @item @code{max-user-bandwidth} (default: @code{#f})
21920 Maximum voice traffic a user can send per second.
21922 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
21923 File name of the sqlite database.
21924 The service's user will become the owner of the directory.
21926 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
21927 File name of the log file.
21928 The service's user will become the owner of the directory.
21930 @item @code{autoban-attempts} (default: @code{10})
21931 Maximum number of logins a user can make in @code{autoban-timeframe}
21932 without getting auto banned for @code{autoban-time}.
21934 @item @code{autoban-timeframe} (default: @code{120})
21935 Timeframe for autoban in seconds.
21937 @item @code{autoban-time} (default: @code{300})
21938 Amount of time in seconds for which a client gets banned
21939 when violating the autoban limits.
21941 @item @code{opus-threshold} (default: @code{100})
21942 Percentage of clients that need to support opus
21943 before switching over to opus audio codec.
21945 @item @code{channel-nesting-limit} (default: @code{10})
21946 How deep channels can be nested at maximum.
21948 @item @code{channelname-regex} (default: @code{#f})
21949 A string in form of a Qt regular expression that channel names must conform to.
21951 @item @code{username-regex} (default: @code{#f})
21952 A string in form of a Qt regular expression that user names must conform to.
21954 @item @code{text-message-length} (default: @code{5000})
21955 Maximum size in bytes that a user can send in one text chat message.
21957 @item @code{image-message-length} (default: @code{(* 128 1024)})
21958 Maximum size in bytes that a user can send in one image message.
21960 @item @code{cert-required?} (default: @code{#f})
21961 If it is set to @code{#t} clients that use weak password authentication
21962 will not be accepted. Users must have completed the certificate wizard to join.
21964 @item @code{remember-channel?} (default: @code{#f})
21965 Should murmur remember the last channel each user was in when they disconnected
21966 and put them into the remembered channel when they rejoin.
21968 @item @code{allow-html?} (default: @code{#f})
21969 Should html be allowed in text messages, user comments, and channel descriptions.
21971 @item @code{allow-ping?} (default: @code{#f})
21972 Setting to true exposes the current user count, the maximum user count, and
21973 the server's maximum bandwidth per client to unauthenticated users. In the
21974 Mumble client, this information is shown in the Connect dialog.
21976 Disabling this setting will prevent public listing of the server.
21978 @item @code{bonjour?} (default: @code{#f})
21979 Should the server advertise itself in the local network through the bonjour protocol.
21981 @item @code{send-version?} (default: @code{#f})
21982 Should the murmur server version be exposed in ping requests.
21984 @item @code{log-days} (default: @code{31})
21985 Murmur also stores logs in the database, which are accessible via RPC.
21986 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
21987 or -1 to disable logging to the database.
21989 @item @code{obfuscate-ips?} (default: @code{#t})
21990 Should logged ips be obfuscated to protect the privacy of users.
21992 @item @code{ssl-cert} (default: @code{#f})
21993 File name of the SSL/TLS certificate used for encrypted connections.
21996 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
21998 @item @code{ssl-key} (default: @code{#f})
21999 Filepath to the ssl private key used for encrypted connections.
22001 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
22004 @item @code{ssl-dh-params} (default: @code{#f})
22005 File name of a PEM-encoded file with Diffie-Hellman parameters
22006 for the SSL/TLS encryption. Alternatively you set it to
22007 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
22008 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
22010 @item @code{ssl-ciphers} (default: @code{#f})
22011 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
22014 This option is specified using
22015 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
22016 OpenSSL cipher list notation}.
22018 It is recommended that you try your cipher string using 'openssl ciphers <string>'
22019 before setting it here, to get a feel for which cipher suites you will get.
22020 After setting this option, it is recommend that you inspect your Murmur log
22021 to ensure that Murmur is using the cipher suites that you expected it to.
22023 Note: Changing this option may impact the backwards compatibility of your
22024 Murmur server, and can remove the ability for older Mumble clients to be able
22027 @item @code{public-registration} (default: @code{#f})
22028 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
22030 You can optionally register your server in the public server list that the
22031 @code{mumble} client shows on startup.
22032 You cannot register your server if you have set a @code{server-password},
22033 or set @code{allow-ping} to @code{#f}.
22035 It might take a few hours until it shows up in the public list.
22037 @item @code{file} (default: @code{#f})
22038 Optional alternative override for this configuration.
22042 @deftp {Data Type} murmur-public-registration-configuration
22043 Configuration for public registration of a murmur service.
22047 This is a display name for your server. Not to be confused with the hostname.
22049 @item @code{password}
22050 A password to identify your registration.
22051 Subsequent updates will need the same password. Don't lose your password.
22054 This should be a @code{http://} or @code{https://} link to your web
22057 @item @code{hostname} (default: @code{#f})
22058 By default your server will be listed by its IP address.
22059 If it is set your server will be linked by this host name instead.
22065 @node Monitoring Services
22066 @subsection Monitoring Services
22068 @subsubheading Tailon Service
22070 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
22071 viewing and searching log files.
22073 The following example will configure the service with default values.
22074 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
22077 (service tailon-service-type)
22080 The following example customises more of the Tailon configuration,
22081 adding @command{sed} to the list of allowed commands.
22084 (service tailon-service-type
22085 (tailon-configuration
22087 (tailon-configuration-file
22088 (allowed-commands '("tail" "grep" "awk" "sed"))))))
22092 @deftp {Data Type} tailon-configuration
22093 Data type representing the configuration of Tailon.
22094 This type has the following parameters:
22097 @item @code{config-file} (default: @code{(tailon-configuration-file)})
22098 The configuration file to use for Tailon. This can be set to a
22099 @dfn{tailon-configuration-file} record value, or any gexp
22100 (@pxref{G-Expressions}).
22102 For example, to instead use a local file, the @code{local-file} function
22106 (service tailon-service-type
22107 (tailon-configuration
22108 (config-file (local-file "./my-tailon.conf"))))
22111 @item @code{package} (default: @code{tailon})
22112 The tailon package to use.
22117 @deftp {Data Type} tailon-configuration-file
22118 Data type representing the configuration options for Tailon.
22119 This type has the following parameters:
22122 @item @code{files} (default: @code{(list "/var/log")})
22123 List of files to display. The list can include strings for a single file
22124 or directory, or a list, where the first item is the name of a
22125 subsection, and the remaining items are the files or directories in that
22128 @item @code{bind} (default: @code{"localhost:8080"})
22129 Address and port to which Tailon should bind on.
22131 @item @code{relative-root} (default: @code{#f})
22132 URL path to use for Tailon, set to @code{#f} to not use a path.
22134 @item @code{allow-transfers?} (default: @code{#t})
22135 Allow downloading the log files in the web interface.
22137 @item @code{follow-names?} (default: @code{#t})
22138 Allow tailing of not-yet existent files.
22140 @item @code{tail-lines} (default: @code{200})
22141 Number of lines to read initially from each file.
22143 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
22144 Commands to allow running. By default, @code{sed} is disabled.
22146 @item @code{debug?} (default: @code{#f})
22147 Set @code{debug?} to @code{#t} to show debug messages.
22149 @item @code{wrap-lines} (default: @code{#t})
22150 Initial line wrapping state in the web interface. Set to @code{#t} to
22151 initially wrap lines (the default), or to @code{#f} to initially not
22154 @item @code{http-auth} (default: @code{#f})
22155 HTTP authentication type to use. Set to @code{#f} to disable
22156 authentication (the default). Supported values are @code{"digest"} or
22159 @item @code{users} (default: @code{#f})
22160 If HTTP authentication is enabled (see @code{http-auth}), access will be
22161 restricted to the credentials provided here. To configure users, use a
22162 list of pairs, where the first element of the pair is the username, and
22163 the 2nd element of the pair is the password.
22166 (tailon-configuration-file
22167 (http-auth "basic")
22168 (users '(("user1" . "password1")
22169 ("user2" . "password2"))))
22176 @subsubheading Darkstat Service
22178 Darkstat is a packet sniffer that captures network traffic, calculates
22179 statistics about usage, and serves reports over HTTP.
22181 @defvar {Scheme Variable} darkstat-service-type
22182 This is the service type for the
22183 @uref{https://unix4lyfe.org/darkstat/, darkstat}
22184 service, its value must be a @code{darkstat-configuration} record as in
22188 (service darkstat-service-type
22189 (darkstat-configuration
22190 (interface "eno1")))
22194 @deftp {Data Type} darkstat-configuration
22195 Data type representing the configuration of @command{darkstat}.
22198 @item @code{package} (default: @code{darkstat})
22199 The darkstat package to use.
22201 @item @code{interface}
22202 Capture traffic on the specified network interface.
22204 @item @code{port} (default: @code{"667"})
22205 Bind the web interface to the specified port.
22207 @item @code{bind-address} (default: @code{"127.0.0.1"})
22208 Bind the web interface to the specified address.
22210 @item @code{base} (default: @code{"/"})
22211 Specify the path of the base URL. This can be useful if
22212 @command{darkstat} is accessed via a reverse proxy.
22217 @subsubheading Prometheus Node Exporter Service
22219 @cindex prometheus-node-exporter
22220 The Prometheus ``node exporter'' makes hardware and operating system statistics
22221 provided by the Linux kernel available for the Prometheus monitoring system.
22222 This service should be deployed on all physical nodes and virtual machines,
22223 where monitoring these statistics is desirable.
22225 @defvar {Scheme variable} prometheus-node-exporter-service-type
22226 This is the service type for the
22227 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
22228 service, its value must be a @code{prometheus-node-exporter-configuration}.
22231 (service prometheus-node-exporter-service-type)
22235 @deftp {Data Type} prometheus-node-exporter-configuration
22236 Data type representing the configuration of @command{node_exporter}.
22239 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
22240 The prometheus-node-exporter package to use.
22242 @item @code{web-listen-address} (default: @code{":9100"})
22243 Bind the web interface to the specified address.
22245 @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
22246 This directory can be used to export metrics specific to this machine.
22247 Files containing metrics in the text format, with the filename ending in
22248 @code{.prom} should be placed in this directory.
22250 @item @code{extra-options} (default: @code{'()})
22251 Extra options to pass to the Prometheus node exporter.
22256 @subsubheading Zabbix server
22257 @cindex zabbix zabbix-server
22258 Zabbix provides monitoring metrics, among others network utilization, CPU load
22259 and disk space consumption:
22262 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
22263 @item Auto-discovery of servers and network devices and interfaces.
22264 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
22265 @item Distributed monitoring with centralized web administration.
22266 @item Native high performance agents.
22267 @item SLA, and ITIL KPI metrics on reporting.
22268 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
22269 @item Remote command execution through Zabbix proxies.
22272 @c %start of fragment
22274 Available @code{zabbix-server-configuration} fields are:
22276 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
22277 The zabbix-server package.
22281 @deftypevr {@code{zabbix-server-configuration} parameter} string user
22282 User who will run the Zabbix server.
22284 Defaults to @samp{"zabbix"}.
22288 @deftypevr {@code{zabbix-server-configuration} parameter} group group
22289 Group who will run the Zabbix server.
22291 Defaults to @samp{"zabbix"}.
22295 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
22296 Database host name.
22298 Defaults to @samp{"127.0.0.1"}.
22302 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
22305 Defaults to @samp{"zabbix"}.
22309 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
22312 Defaults to @samp{"zabbix"}.
22316 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
22317 Database password. Please, use @code{include-files} with
22318 @code{DBPassword=SECRET} inside a specified file instead.
22320 Defaults to @samp{""}.
22324 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
22327 Defaults to @samp{5432}.
22331 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
22332 Specifies where log messages are written to:
22336 @code{system} - syslog.
22339 @code{file} - file specified with @code{log-file} parameter.
22342 @code{console} - standard output.
22346 Defaults to @samp{""}.
22350 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
22351 Log file name for @code{log-type} @code{file} parameter.
22353 Defaults to @samp{"/var/log/zabbix/server.log"}.
22357 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
22360 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
22364 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
22365 The location of certificate authority (CA) files for SSL server
22366 certificate verification.
22368 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
22372 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
22373 Location of SSL client certificates.
22375 Defaults to @samp{"/etc/ssl/certs"}.
22379 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
22380 Extra options will be appended to Zabbix server configuration file.
22382 Defaults to @samp{""}.
22386 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
22387 You may include individual files or all files in a directory in the
22388 configuration file.
22390 Defaults to @samp{()}.
22394 @c %end of fragment
22396 @subsubheading Zabbix agent
22397 @cindex zabbix zabbix-agent
22399 Zabbix agent gathers information for Zabbix server.
22401 @c %start of fragment
22403 Available @code{zabbix-agent-configuration} fields are:
22405 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
22406 The zabbix-agent package.
22410 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
22411 User who will run the Zabbix agent.
22413 Defaults to @samp{"zabbix"}.
22417 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
22418 Group who will run the Zabbix agent.
22420 Defaults to @samp{"zabbix"}.
22424 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
22425 Unique, case sensitive hostname which is required for active checks and
22426 must match hostname as configured on the server.
22428 Defaults to @samp{""}.
22432 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
22433 Specifies where log messages are written to:
22437 @code{system} - syslog.
22440 @code{file} - file specified with @code{log-file} parameter.
22443 @code{console} - standard output.
22447 Defaults to @samp{""}.
22451 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
22452 Log file name for @code{log-type} @code{file} parameter.
22454 Defaults to @samp{"/var/log/zabbix/agent.log"}.
22458 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
22461 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
22465 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
22466 List of IP addresses, optionally in CIDR notation, or hostnames of
22467 Zabbix servers and Zabbix proxies. Incoming connections will be
22468 accepted only from the hosts listed here.
22470 Defaults to @samp{("127.0.0.1")}.
22474 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
22475 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
22476 proxies for active checks. If port is not specified, default port is
22477 used. If this parameter is not specified, active checks are disabled.
22479 Defaults to @samp{("127.0.0.1")}.
22483 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
22484 Extra options will be appended to Zabbix server configuration file.
22486 Defaults to @samp{""}.
22490 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
22491 You may include individual files or all files in a directory in the
22492 configuration file.
22494 Defaults to @samp{()}.
22498 @c %end of fragment
22500 @subsubheading Zabbix front-end
22501 @cindex zabbix zabbix-front-end
22503 This service provides a WEB interface to Zabbix server.
22505 @c %start of fragment
22507 Available @code{zabbix-front-end-configuration} fields are:
22509 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
22510 NGINX configuration.
22514 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
22515 Database host name.
22517 Defaults to @samp{"localhost"}.
22521 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
22524 Defaults to @samp{5432}.
22528 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
22531 Defaults to @samp{"zabbix"}.
22535 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
22538 Defaults to @samp{"zabbix"}.
22542 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
22543 Database password. Please, use @code{db-secret-file} instead.
22545 Defaults to @samp{""}.
22549 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
22550 Secret file containing the credentials for the Zabbix front-end. The value
22551 must be a local file name, not a G-expression. You are expected to create
22552 this file manually. Its contents will be copied into @file{zabbix.conf.php}
22553 as the value of @code{$DB['PASSWORD']}.
22555 Defaults to @samp{""}.
22559 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
22560 Zabbix server hostname.
22562 Defaults to @samp{"localhost"}.
22566 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
22567 Zabbix server port.
22569 Defaults to @samp{10051}.
22574 @c %end of fragment
22576 @node Kerberos Services
22577 @subsection Kerberos Services
22580 The @code{(gnu services kerberos)} module provides services relating to
22581 the authentication protocol @dfn{Kerberos}.
22583 @subsubheading Krb5 Service
22585 Programs using a Kerberos client library normally
22586 expect a configuration file in @file{/etc/krb5.conf}.
22587 This service generates such a file from a definition provided in the
22588 operating system declaration.
22589 It does not cause any daemon to be started.
22591 No ``keytab'' files are provided by this service---you must explicitly create them.
22592 This service is known to work with the MIT client library, @code{mit-krb5}.
22593 Other implementations have not been tested.
22595 @defvr {Scheme Variable} krb5-service-type
22596 A service type for Kerberos 5 clients.
22600 Here is an example of its use:
22602 (service krb5-service-type
22603 (krb5-configuration
22604 (default-realm "EXAMPLE.COM")
22605 (allow-weak-crypto? #t)
22608 (name "EXAMPLE.COM")
22609 (admin-server "groucho.example.com")
22610 (kdc "karl.example.com"))
22613 (admin-server "kerb-admin.argrx.edu")
22614 (kdc "keys.argrx.edu"))))))
22618 This example provides a Kerberos@tie{}5 client configuration which:
22620 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
22621 of which have distinct administration servers and key distribution centers;
22622 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
22623 specified by clients;
22624 @item Accepts services which only support encryption types known to be weak.
22627 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
22628 Only the most commonly used ones are described here.
22629 For a full list, and more detailed explanation of each, see the MIT
22630 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
22634 @deftp {Data Type} krb5-realm
22635 @cindex realm, kerberos
22638 This field is a string identifying the name of the realm.
22639 A common convention is to use the fully qualified DNS name of your organization,
22640 converted to upper case.
22642 @item @code{admin-server}
22643 This field is a string identifying the host where the administration server is
22647 This field is a string identifying the key distribution center
22652 @deftp {Data Type} krb5-configuration
22655 @item @code{allow-weak-crypto?} (default: @code{#f})
22656 If this flag is @code{#t} then services which only offer encryption algorithms
22657 known to be weak will be accepted.
22659 @item @code{default-realm} (default: @code{#f})
22660 This field should be a string identifying the default Kerberos
22661 realm for the client.
22662 You should set this field to the name of your Kerberos realm.
22663 If this value is @code{#f}
22664 then a realm must be specified with every Kerberos principal when invoking programs
22665 such as @command{kinit}.
22667 @item @code{realms}
22668 This should be a non-empty list of @code{krb5-realm} objects, which clients may
22670 Normally, one of them will have a @code{name} field matching the @code{default-realm}
22676 @subsubheading PAM krb5 Service
22679 The @code{pam-krb5} service allows for login authentication and password
22680 management via Kerberos.
22681 You will need this service if you want PAM enabled applications to authenticate
22682 users using Kerberos.
22684 @defvr {Scheme Variable} pam-krb5-service-type
22685 A service type for the Kerberos 5 PAM module.
22688 @deftp {Data Type} pam-krb5-configuration
22689 Data type representing the configuration of the Kerberos 5 PAM module.
22690 This type has the following parameters:
22692 @item @code{pam-krb5} (default: @code{pam-krb5})
22693 The pam-krb5 package to use.
22695 @item @code{minimum-uid} (default: @code{1000})
22696 The smallest user ID for which Kerberos authentications should be attempted.
22697 Local accounts with lower values will silently fail to authenticate.
22702 @node LDAP Services
22703 @subsection LDAP Services
22705 @cindex nslcd, LDAP service
22707 The @code{(gnu services authentication)} module provides the
22708 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
22709 server. In addition to configuring the service itself, you may want to add
22710 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
22711 Switch} for detailed information.
22713 Here is a simple operating system declaration with a default configuration of
22714 the @code{nslcd-service-type} and a Name Service Switch configuration that
22715 consults the @code{ldap} name service last:
22718 (use-service-modules authentication)
22719 (use-modules (gnu system nss))
22725 (service nslcd-service-type)
22726 (service dhcp-client-service-type)
22728 (name-service-switch
22729 (let ((services (list (name-service (name "db"))
22730 (name-service (name "files"))
22731 (name-service (name "ldap")))))
22732 (name-service-switch
22733 (inherit %mdns-host-lookup-nss)
22734 (password services)
22737 (netgroup services)
22738 (gshadow services)))))
22741 @c %start of generated documentation for nslcd-configuration
22743 Available @code{nslcd-configuration} fields are:
22745 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
22746 The @code{nss-pam-ldapd} package to use.
22750 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
22751 The number of threads to start that can handle requests and perform LDAP
22752 queries. Each thread opens a separate connection to the LDAP server.
22753 The default is to start 5 threads.
22755 Defaults to @samp{disabled}.
22759 @deftypevr {@code{nslcd-configuration} parameter} string uid
22760 This specifies the user id with which the daemon should be run.
22762 Defaults to @samp{"nslcd"}.
22766 @deftypevr {@code{nslcd-configuration} parameter} string gid
22767 This specifies the group id with which the daemon should be run.
22769 Defaults to @samp{"nslcd"}.
22773 @deftypevr {@code{nslcd-configuration} parameter} log-option log
22774 This option controls the way logging is done via a list containing
22775 SCHEME and LEVEL. The SCHEME argument may either be the symbols
22776 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
22777 argument is optional and specifies the log level. The log level may be
22778 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
22779 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
22780 specified log level or higher are logged.
22782 Defaults to @samp{("/var/log/nslcd" info)}.
22786 @deftypevr {@code{nslcd-configuration} parameter} list uri
22787 The list of LDAP server URIs. Normally, only the first server will be
22788 used with the following servers as fall-back.
22790 Defaults to @samp{("ldap://localhost:389/")}.
22794 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
22795 The version of the LDAP protocol to use. The default is to use the
22796 maximum version supported by the LDAP library.
22798 Defaults to @samp{disabled}.
22802 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
22803 Specifies the distinguished name with which to bind to the directory
22804 server for lookups. The default is to bind anonymously.
22806 Defaults to @samp{disabled}.
22810 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
22811 Specifies the credentials with which to bind. This option is only
22812 applicable when used with binddn.
22814 Defaults to @samp{disabled}.
22818 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
22819 Specifies the distinguished name to use when the root user tries to
22820 modify a user's password using the PAM module.
22822 Defaults to @samp{disabled}.
22826 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
22827 Specifies the credentials with which to bind if the root user tries to
22828 change a user's password. This option is only applicable when used with
22831 Defaults to @samp{disabled}.
22835 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
22836 Specifies the SASL mechanism to be used when performing SASL
22839 Defaults to @samp{disabled}.
22843 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
22844 Specifies the SASL realm to be used when performing SASL authentication.
22846 Defaults to @samp{disabled}.
22850 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
22851 Specifies the authentication identity to be used when performing SASL
22854 Defaults to @samp{disabled}.
22858 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
22859 Specifies the authorization identity to be used when performing SASL
22862 Defaults to @samp{disabled}.
22866 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
22867 Determines whether the LDAP server host name should be canonicalised. If
22868 this is enabled the LDAP library will do a reverse host name lookup. By
22869 default, it is left up to the LDAP library whether this check is
22872 Defaults to @samp{disabled}.
22876 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
22877 Set the name for the GSS-API Kerberos credentials cache.
22879 Defaults to @samp{disabled}.
22883 @deftypevr {@code{nslcd-configuration} parameter} string base
22884 The directory search base.
22886 Defaults to @samp{"dc=example,dc=com"}.
22890 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
22891 Specifies the search scope (subtree, onelevel, base or children). The
22892 default scope is subtree; base scope is almost never useful for name
22893 service lookups; children scope is not supported on all servers.
22895 Defaults to @samp{(subtree)}.
22899 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
22900 Specifies the policy for dereferencing aliases. The default policy is
22901 to never dereference aliases.
22903 Defaults to @samp{disabled}.
22907 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
22908 Specifies whether automatic referral chasing should be enabled. The
22909 default behaviour is to chase referrals.
22911 Defaults to @samp{disabled}.
22915 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
22916 This option allows for custom attributes to be looked up instead of the
22917 default RFC 2307 attributes. It is a list of maps, each consisting of
22918 the name of a map, the RFC 2307 attribute to match and the query
22919 expression for the attribute as it is available in the directory.
22921 Defaults to @samp{()}.
22925 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
22926 A list of filters consisting of the name of a map to which the filter
22927 applies and an LDAP search filter expression.
22929 Defaults to @samp{()}.
22933 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
22934 Specifies the time limit in seconds to use when connecting to the
22935 directory server. The default value is 10 seconds.
22937 Defaults to @samp{disabled}.
22941 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
22942 Specifies the time limit (in seconds) to wait for a response from the
22943 LDAP server. A value of zero, which is the default, is to wait
22944 indefinitely for searches to be completed.
22946 Defaults to @samp{disabled}.
22950 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
22951 Specifies the period if inactivity (in seconds) after which the con‐
22952 nection to the LDAP server will be closed. The default is not to time
22955 Defaults to @samp{disabled}.
22959 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
22960 Specifies the number of seconds to sleep when connecting to all LDAP
22961 servers fails. By default one second is waited between the first
22962 failure and the first retry.
22964 Defaults to @samp{disabled}.
22968 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
22969 Specifies the time after which the LDAP server is considered to be
22970 permanently unavailable. Once this time is reached retries will be done
22971 only once per this time period. The default value is 10 seconds.
22973 Defaults to @samp{disabled}.
22977 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
22978 Specifies whether to use SSL/TLS or not (the default is not to). If
22979 'start-tls is specified then StartTLS is used rather than raw LDAP over
22982 Defaults to @samp{disabled}.
22986 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
22987 Specifies what checks to perform on a server-supplied certificate. The
22988 meaning of the values is described in the ldap.conf(5) manual page.
22990 Defaults to @samp{disabled}.
22994 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
22995 Specifies the directory containing X.509 certificates for peer authen‐
22996 tication. This parameter is ignored when using GnuTLS.
22998 Defaults to @samp{disabled}.
23002 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
23003 Specifies the path to the X.509 certificate for peer authentication.
23005 Defaults to @samp{disabled}.
23009 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
23010 Specifies the path to an entropy source. This parameter is ignored when
23013 Defaults to @samp{disabled}.
23017 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
23018 Specifies the ciphers to use for TLS as a string.
23020 Defaults to @samp{disabled}.
23024 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
23025 Specifies the path to the file containing the local certificate for
23026 client TLS authentication.
23028 Defaults to @samp{disabled}.
23032 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
23033 Specifies the path to the file containing the private key for client TLS
23036 Defaults to @samp{disabled}.
23040 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
23041 Set this to a number greater than 0 to request paged results from the
23042 LDAP server in accordance with RFC2696. The default (0) is to not
23043 request paged results.
23045 Defaults to @samp{disabled}.
23049 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
23050 This option prevents group membership lookups through LDAP for the
23051 specified users. Alternatively, the value 'all-local may be used. With
23052 that value nslcd builds a full list of non-LDAP users on startup.
23054 Defaults to @samp{disabled}.
23058 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
23059 This option ensures that LDAP users with a numeric user id lower than
23060 the specified value are ignored.
23062 Defaults to @samp{disabled}.
23066 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
23067 This option specifies an offset that is added to all LDAP numeric user
23068 ids. This can be used to avoid user id collisions with local users.
23070 Defaults to @samp{disabled}.
23074 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
23075 This option specifies an offset that is added to all LDAP numeric group
23076 ids. This can be used to avoid user id collisions with local groups.
23078 Defaults to @samp{disabled}.
23082 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
23083 If this option is set, the member attribute of a group may point to
23084 another group. Members of nested groups are also returned in the higher
23085 level group and parent groups are returned when finding groups for a
23086 specific user. The default is not to perform extra searches for nested
23089 Defaults to @samp{disabled}.
23093 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
23094 If this option is set, the group member list is not retrieved when
23095 looking up groups. Lookups for finding which groups a user belongs to
23096 will remain functional so the user will likely still get the correct
23097 groups assigned on login.
23099 Defaults to @samp{disabled}.
23103 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
23104 If this option is set, functions which cause all user/group entries to
23105 be loaded from the directory will not succeed in doing so. This can
23106 dramatically reduce LDAP server load in situations where there are a
23107 great number of users and/or groups. This option is not recommended for
23108 most configurations.
23110 Defaults to @samp{disabled}.
23114 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
23115 This option can be used to specify how user and group names are verified
23116 within the system. This pattern is used to check all user and group
23117 names that are requested and returned from LDAP.
23119 Defaults to @samp{disabled}.
23123 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
23124 This specifies whether or not to perform searches using case-insensitive
23125 matching. Enabling this could open up the system to authorization
23126 bypass vulnerabilities and introduce nscd cache poisoning
23127 vulnerabilities which allow denial of service.
23129 Defaults to @samp{disabled}.
23133 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
23134 This option specifies whether password policy controls are requested and
23135 handled from the LDAP server when performing user authentication.
23137 Defaults to @samp{disabled}.
23141 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
23142 By default nslcd performs an LDAP search with the user's credentials
23143 after BIND (authentication) to ensure that the BIND operation was
23144 successful. The default search is a simple check to see if the user's
23145 DN exists. A search filter can be specified that will be used instead.
23146 It should return at least one entry.
23148 Defaults to @samp{disabled}.
23152 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
23153 This option allows flexible fine tuning of the authorisation check that
23154 should be performed. The search filter specified is executed and if any
23155 entries match, access is granted, otherwise access is denied.
23157 Defaults to @samp{disabled}.
23161 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
23162 If this option is set password modification using pam_ldap will be
23163 denied and the specified message will be presented to the user instead.
23164 The message can be used to direct the user to an alternative means of
23165 changing their password.
23167 Defaults to @samp{disabled}.
23171 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
23172 List of pam service names for which LDAP authentication should suffice.
23174 Defaults to @samp{()}.
23178 @c %end of generated documentation for nslcd-configuration
23182 @subsection Web Services
23187 The @code{(gnu services web)} module provides the Apache HTTP Server,
23188 the nginx web server, and also a fastcgi wrapper daemon.
23190 @subsubheading Apache HTTP Server
23192 @deffn {Scheme Variable} httpd-service-type
23193 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
23194 (@dfn{httpd}). The value for this service type is a
23195 @code{httpd-configuration} record.
23197 A simple example configuration is given below.
23200 (service httpd-service-type
23201 (httpd-configuration
23204 (server-name "www.example.com")
23205 (document-root "/srv/http/www.example.com")))))
23208 Other services can also extend the @code{httpd-service-type} to add to
23212 (simple-service 'www.example.com-server httpd-service-type
23216 (list (string-join '("ServerName www.example.com"
23217 "DocumentRoot /srv/http/www.example.com")
23222 The details for the @code{httpd-configuration}, @code{httpd-module},
23223 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
23226 @deffn {Data Type} httpd-configuration
23227 This data type represents the configuration for the httpd service.
23230 @item @code{package} (default: @code{httpd})
23231 The httpd package to use.
23233 @item @code{pid-file} (default: @code{"/var/run/httpd"})
23234 The pid file used by the shepherd-service.
23236 @item @code{config} (default: @code{(httpd-config-file)})
23237 The configuration file to use with the httpd service. The default value
23238 is a @code{httpd-config-file} record, but this can also be a different
23239 G-expression that generates a file, for example a @code{plain-file}. A
23240 file outside of the store can also be specified through a string.
23245 @deffn {Data Type} httpd-module
23246 This data type represents a module for the httpd service.
23250 The name of the module.
23253 The file for the module. This can be relative to the httpd package being
23254 used, the absolute location of a file, or a G-expression for a file
23255 within the store, for example @code{(file-append mod-wsgi
23256 "/modules/mod_wsgi.so")}.
23261 @defvr {Scheme Variable} %default-httpd-modules
23262 A default list of @code{httpd-module} objects.
23265 @deffn {Data Type} httpd-config-file
23266 This data type represents a configuration file for the httpd service.
23269 @item @code{modules} (default: @code{%default-httpd-modules})
23270 The modules to load. Additional modules can be added here, or loaded by
23271 additional configuration.
23273 For example, in order to handle requests for PHP files, you can use Apache’s
23274 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
23277 (service httpd-service-type
23278 (httpd-configuration
23283 (name "proxy_module")
23284 (file "modules/mod_proxy.so"))
23286 (name "proxy_fcgi_module")
23287 (file "modules/mod_proxy_fcgi.so"))
23288 %default-httpd-modules))
23289 (extra-config (list "\
23290 <FilesMatch \\.php$>
23291 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
23292 </FilesMatch>"))))))
23293 (service php-fpm-service-type
23294 (php-fpm-configuration
23295 (socket "/var/run/php-fpm.sock")
23296 (socket-group "httpd")))
23299 @item @code{server-root} (default: @code{httpd})
23300 The @code{ServerRoot} in the configuration file, defaults to the httpd
23301 package. Directives including @code{Include} and @code{LoadModule} are
23302 taken as relative to the server root.
23304 @item @code{server-name} (default: @code{#f})
23305 The @code{ServerName} in the configuration file, used to specify the
23306 request scheme, hostname and port that the server uses to identify
23309 This doesn't need to be set in the server config, and can be specified
23310 in virtual hosts. The default is @code{#f} to not specify a
23313 @item @code{document-root} (default: @code{"/srv/http"})
23314 The @code{DocumentRoot} from which files will be served.
23316 @item @code{listen} (default: @code{'("80")})
23317 The list of values for the @code{Listen} directives in the config
23318 file. The value should be a list of strings, when each string can
23319 specify the port number to listen on, and optionally the IP address and
23322 @item @code{pid-file} (default: @code{"/var/run/httpd"})
23323 The @code{PidFile} to use. This should match the @code{pid-file} set in
23324 the @code{httpd-configuration} so that the Shepherd service is
23325 configured correctly.
23327 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
23328 The @code{ErrorLog} to which the server will log errors.
23330 @item @code{user} (default: @code{"httpd"})
23331 The @code{User} which the server will answer requests as.
23333 @item @code{group} (default: @code{"httpd"})
23334 The @code{Group} which the server will answer requests as.
23336 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
23337 A flat list of strings and G-expressions which will be added to the end
23338 of the configuration file.
23340 Any values which the service is extended with will be appended to this
23346 @deffn {Data Type} httpd-virtualhost
23347 This data type represents a virtualhost configuration block for the httpd service.
23349 These should be added to the extra-config for the httpd-service.
23352 (simple-service 'www.example.com-server httpd-service-type
23356 (list (string-join '("ServerName www.example.com"
23357 "DocumentRoot /srv/http/www.example.com")
23362 @item @code{addresses-and-ports}
23363 The addresses and ports for the @code{VirtualHost} directive.
23365 @item @code{contents}
23366 The contents of the @code{VirtualHost} directive, this should be a list
23367 of strings and G-expressions.
23372 @subsubheading NGINX
23374 @deffn {Scheme Variable} nginx-service-type
23375 Service type for the @uref{https://nginx.org/,NGinx} web server. The
23376 value for this service type is a @code{<nginx-configuration>} record.
23378 A simple example configuration is given below.
23381 (service nginx-service-type
23382 (nginx-configuration
23384 (list (nginx-server-configuration
23385 (server-name '("www.example.com"))
23386 (root "/srv/http/www.example.com"))))))
23389 In addition to adding server blocks to the service configuration
23390 directly, this service can be extended by other services to add server
23391 blocks, as in this example:
23394 (simple-service 'my-extra-server nginx-service-type
23395 (list (nginx-server-configuration
23396 (root "/srv/http/extra-website")
23397 (try-files (list "$uri" "$uri/index.html")))))
23401 At startup, @command{nginx} has not yet read its configuration file, so
23402 it uses a default file to log error messages. If it fails to load its
23403 configuration file, that is where error messages are logged. After the
23404 configuration file is loaded, the default error log file changes as per
23405 configuration. In our case, startup error messages can be found in
23406 @file{/var/run/nginx/logs/error.log}, and after configuration in
23407 @file{/var/log/nginx/error.log}. The second location can be changed
23408 with the @var{log-directory} configuration option.
23410 @deffn {Data Type} nginx-configuration
23411 This data type represents the configuration for NGinx. Some
23412 configuration can be done through this and the other provided record
23413 types, or alternatively, a config file can be provided.
23416 @item @code{nginx} (default: @code{nginx})
23417 The nginx package to use.
23419 @item @code{log-directory} (default: @code{"/var/log/nginx"})
23420 The directory to which NGinx will write log files.
23422 @item @code{run-directory} (default: @code{"/var/run/nginx"})
23423 The directory in which NGinx will create a pid file, and write temporary
23426 @item @code{server-blocks} (default: @code{'()})
23427 A list of @dfn{server blocks} to create in the generated configuration
23428 file, the elements should be of type
23429 @code{<nginx-server-configuration>}.
23431 The following example would setup NGinx to serve @code{www.example.com}
23432 from the @code{/srv/http/www.example.com} directory, without using
23435 (service nginx-service-type
23436 (nginx-configuration
23438 (list (nginx-server-configuration
23439 (server-name '("www.example.com"))
23440 (root "/srv/http/www.example.com"))))))
23443 @item @code{upstream-blocks} (default: @code{'()})
23444 A list of @dfn{upstream blocks} to create in the generated configuration
23445 file, the elements should be of type
23446 @code{<nginx-upstream-configuration>}.
23448 Configuring upstreams through the @code{upstream-blocks} can be useful
23449 when combined with @code{locations} in the
23450 @code{<nginx-server-configuration>} records. The following example
23451 creates a server configuration with one location configuration, that
23452 will proxy requests to a upstream configuration, which will handle
23453 requests with two servers.
23458 (nginx-configuration
23460 (list (nginx-server-configuration
23461 (server-name '("www.example.com"))
23462 (root "/srv/http/www.example.com")
23465 (nginx-location-configuration
23467 (body '("proxy_pass http://server-proxy;"))))))))
23469 (list (nginx-upstream-configuration
23470 (name "server-proxy")
23471 (servers (list "server1.example.com"
23472 "server2.example.com")))))))
23475 @item @code{file} (default: @code{#f})
23476 If a configuration @var{file} is provided, this will be used, rather than
23477 generating a configuration file from the provided @code{log-directory},
23478 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
23479 proper operation, these arguments should match what is in @var{file} to ensure
23480 that the directories are created when the service is activated.
23482 This can be useful if you have an existing configuration file, or it's
23483 not possible to do what is required through the other parts of the
23484 nginx-configuration record.
23486 @item @code{server-names-hash-bucket-size} (default: @code{#f})
23487 Bucket size for the server names hash tables, defaults to @code{#f} to
23488 use the size of the processors cache line.
23490 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
23491 Maximum bucket size for the server names hash tables.
23493 @item @code{modules} (default: @code{'()})
23494 List of nginx dynamic modules to load. This should be a list of file
23495 names of loadable modules, as in this example:
23500 (file-append nginx-accept-language-module "\
23501 /etc/nginx/modules/ngx_http_accept_language_module.so")
23502 (file-append nginx-lua-module "\
23503 /etc/nginx/modules/ngx_http_lua_module.so")))
23506 @item @code{lua-package-path} (default: @code{'()})
23507 List of nginx lua packages to load. This should be a list of package
23508 names of loadable lua modules, as in this example:
23511 (lua-package-path (list lua-resty-core
23518 @item @code{lua-package-cpath} (default: @code{'()})
23519 List of nginx lua C packages to load. This should be a list of package
23520 names of loadable lua C modules, as in this example:
23523 (lua-package-cpath (list lua-resty-signal))
23526 @item @code{global-directives} (default: @code{'((events . ()))})
23527 Association list of global directives for the top level of the nginx
23528 configuration. Values may themselves be association lists.
23532 `((worker_processes . 16)
23534 (events . ((worker_connections . 1024)))))
23537 @item @code{extra-content} (default: @code{""})
23538 Extra content for the @code{http} block. Should be string or a string
23539 valued G-expression.
23544 @deftp {Data Type} nginx-server-configuration
23545 Data type representing the configuration of an nginx server block.
23546 This type has the following parameters:
23549 @item @code{listen} (default: @code{'("80" "443 ssl")})
23550 Each @code{listen} directive sets the address and port for IP, or the
23551 path for a UNIX-domain socket on which the server will accept requests.
23552 Both address and port, or only address or only port can be specified.
23553 An address may also be a hostname, for example:
23556 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
23559 @item @code{server-name} (default: @code{(list 'default)})
23560 A list of server names this server represents. @code{'default} represents the
23561 default server for connections matching no other server.
23563 @item @code{root} (default: @code{"/srv/http"})
23564 Root of the website nginx will serve.
23566 @item @code{locations} (default: @code{'()})
23567 A list of @dfn{nginx-location-configuration} or
23568 @dfn{nginx-named-location-configuration} records to use within this
23571 @item @code{index} (default: @code{(list "index.html")})
23572 Index files to look for when clients ask for a directory. If it cannot be found,
23573 Nginx will send the list of files in the directory.
23575 @item @code{try-files} (default: @code{'()})
23576 A list of files whose existence is checked in the specified order.
23577 @code{nginx} will use the first file it finds to process the request.
23579 @item @code{ssl-certificate} (default: @code{#f})
23580 Where to find the certificate for secure connections. Set it to @code{#f} if
23581 you don't have a certificate or you don't want to use HTTPS.
23583 @item @code{ssl-certificate-key} (default: @code{#f})
23584 Where to find the private key for secure connections. Set it to @code{#f} if
23585 you don't have a key or you don't want to use HTTPS.
23587 @item @code{server-tokens?} (default: @code{#f})
23588 Whether the server should add its configuration to response.
23590 @item @code{raw-content} (default: @code{'()})
23591 A list of raw lines added to the server block.
23596 @deftp {Data Type} nginx-upstream-configuration
23597 Data type representing the configuration of an nginx @code{upstream}
23598 block. This type has the following parameters:
23602 Name for this group of servers.
23604 @item @code{servers}
23605 Specify the addresses of the servers in the group. The address can be
23606 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
23607 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
23608 prefix @samp{unix:}. For addresses using an IP address or domain name,
23609 the default port is 80, and a different port can be specified
23615 @deftp {Data Type} nginx-location-configuration
23616 Data type representing the configuration of an nginx @code{location}
23617 block. This type has the following parameters:
23621 URI which this location block matches.
23623 @anchor{nginx-location-configuration body}
23625 Body of the location block, specified as a list of strings. This can contain
23627 configuration directives. For example, to pass requests to a upstream
23628 server group defined using an @code{nginx-upstream-configuration} block,
23629 the following directive would be specified in the body @samp{(list "proxy_pass
23630 http://upstream-name;")}.
23635 @deftp {Data Type} nginx-named-location-configuration
23636 Data type representing the configuration of an nginx named location
23637 block. Named location blocks are used for request redirection, and not
23638 used for regular request processing. This type has the following
23643 Name to identify this location block.
23646 @xref{nginx-location-configuration body}, as the body for named location
23647 blocks can be used in a similar way to the
23648 @code{nginx-location-configuration body}. One restriction is that the
23649 body of a named location block cannot contain location blocks.
23654 @subsubheading Varnish Cache
23656 Varnish is a fast cache server that sits in between web applications
23657 and end users. It proxies requests from clients and caches the
23658 accessed URLs such that multiple requests for the same resource only
23659 creates one request to the back-end.
23661 @defvr {Scheme Variable} varnish-service-type
23662 Service type for the Varnish daemon.
23665 @deftp {Data Type} varnish-configuration
23666 Data type representing the @code{varnish} service configuration.
23667 This type has the following parameters:
23670 @item @code{package} (default: @code{varnish})
23671 The Varnish package to use.
23673 @item @code{name} (default: @code{"default"})
23674 A name for this Varnish instance. Varnish will create a directory in
23675 @file{/var/varnish/} with this name and keep temporary files there. If
23676 the name starts with a forward slash, it is interpreted as an absolute
23679 Pass the @code{-n} argument to other Varnish programs to connect to the
23680 named instance, e.g.@: @command{varnishncsa -n default}.
23682 @item @code{backend} (default: @code{"localhost:8080"})
23683 The backend to use. This option has no effect if @code{vcl} is set.
23685 @item @code{vcl} (default: #f)
23686 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
23687 is @code{#f}, Varnish will proxy @code{backend} using the default
23688 configuration. Otherwise this must be a file-like object with valid
23691 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
23692 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
23693 can do something along these lines:
23696 (define %gnu-mirror
23697 (plain-file "gnu.vcl"
23699 backend gnu @{ .host = \"www.gnu.org\"; @}"))
23703 (services (cons (service varnish-service-type
23704 (varnish-configuration
23706 (vcl %gnu-mirror)))
23710 The configuration of an already running Varnish instance can be inspected
23711 and changed using the @command{varnishadm} program.
23713 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
23714 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
23715 comprehensive documentation on Varnish and its configuration language.
23717 @item @code{listen} (default: @code{'("localhost:80")})
23718 List of addresses Varnish will listen on.
23720 @item @code{storage} (default: @code{'("malloc,128m")})
23721 List of storage backends that will be available in VCL.
23723 @item @code{parameters} (default: @code{'()})
23724 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
23726 @item @code{extra-options} (default: @code{'()})
23727 Additional arguments to pass to the @command{varnishd} process.
23732 @subsubheading Patchwork
23734 Patchwork is a patch tracking system. It can collect patches sent to a
23735 mailing list, and display them in a web interface.
23737 @defvr {Scheme Variable} patchwork-service-type
23738 Service type for Patchwork.
23741 The following example is an example of a minimal service for Patchwork, for
23742 the @code{patchwork.example.com} domain.
23745 (service patchwork-service-type
23746 (patchwork-configuration
23747 (domain "patchwork.example.com")
23749 (patchwork-settings-module
23750 (allowed-hosts (list domain))
23751 (default-from-email "patchwork@@patchwork.example.com")))
23752 (getmail-retriever-config
23753 (getmail-retriever-configuration
23754 (type "SimpleIMAPSSLRetriever")
23755 (server "imap.example.com")
23757 (username "patchwork")
23759 (list (file-append coreutils "/bin/cat")
23760 "/etc/getmail-patchwork-imap-password"))
23762 '((mailboxes . ("Patches"))))))))
23766 There are three records for configuring the Patchwork service. The
23767 @code{<patchwork-configuration>} relates to the configuration for Patchwork
23768 within the HTTPD service.
23770 The @code{settings-module} field within the @code{<patchwork-configuration>}
23771 record can be populated with the @code{<patchwork-settings-module>} record,
23772 which describes a settings module that is generated within the Guix store.
23774 For the @code{database-configuration} field within the
23775 @code{<patchwork-settings-module>}, the
23776 @code{<patchwork-database-configuration>} must be used.
23778 @deftp {Data Type} patchwork-configuration
23779 Data type representing the Patchwork service configuration. This type has the
23780 following parameters:
23783 @item @code{patchwork} (default: @code{patchwork})
23784 The Patchwork package to use.
23786 @item @code{domain}
23787 The domain to use for Patchwork, this is used in the HTTPD service virtual
23790 @item @code{settings-module}
23791 The settings module to use for Patchwork. As a Django application, Patchwork
23792 is configured with a Python module containing the settings. This can either be
23793 an instance of the @code{<patchwork-settings-module>} record, any other record
23794 that represents the settings in the store, or a directory outside of the
23797 @item @code{static-path} (default: @code{"/static/"})
23798 The path under which the HTTPD service should serve the static files.
23800 @item @code{getmail-retriever-config}
23801 The getmail-retriever-configuration record value to use with
23802 Patchwork. Getmail will be configured with this value, the messages will be
23803 delivered to Patchwork.
23808 @deftp {Data Type} patchwork-settings-module
23809 Data type representing a settings module for Patchwork. Some of these
23810 settings relate directly to Patchwork, but others relate to Django, the web
23811 framework used by Patchwork, or the Django Rest Framework library. This type
23812 has the following parameters:
23815 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
23816 The database connection settings used for Patchwork. See the
23817 @code{<patchwork-database-configuration>} record type for more information.
23819 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
23820 Patchwork, as a Django web application uses a secret key for cryptographically
23821 signing values. This file should contain a unique unpredictable value.
23823 If this file does not exist, it will be created and populated with a random
23824 value by the patchwork-setup shepherd service.
23826 This setting relates to Django.
23828 @item @code{allowed-hosts}
23829 A list of valid hosts for this Patchwork service. This should at least include
23830 the domain specified in the @code{<patchwork-configuration>} record.
23832 This is a Django setting.
23834 @item @code{default-from-email}
23835 The email address from which Patchwork should send email by default.
23837 This is a Patchwork setting.
23839 @item @code{static-url} (default: @code{#f})
23840 The URL to use when serving static assets. It can be part of a URL, or a full
23841 URL, but must end in a @code{/}.
23843 If the default value is used, the @code{static-path} value from the
23844 @code{<patchwork-configuration>} record will be used.
23846 This is a Django setting.
23848 @item @code{admins} (default: @code{'()})
23849 Email addresses to send the details of errors that occur. Each value should
23850 be a list containing two elements, the name and then the email address.
23852 This is a Django setting.
23854 @item @code{debug?} (default: @code{#f})
23855 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
23856 messages will be shown.
23858 This is a Django setting.
23860 @item @code{enable-rest-api?} (default: @code{#t})
23861 Whether to enable the Patchwork REST API.
23863 This is a Patchwork setting.
23865 @item @code{enable-xmlrpc?} (default: @code{#t})
23866 Whether to enable the XML RPC API.
23868 This is a Patchwork setting.
23870 @item @code{force-https-links?} (default: @code{#t})
23871 Whether to use HTTPS links on Patchwork pages.
23873 This is a Patchwork setting.
23875 @item @code{extra-settings} (default: @code{""})
23876 Extra code to place at the end of the Patchwork settings module.
23881 @deftp {Data Type} patchwork-database-configuration
23882 Data type representing the database configuration for Patchwork.
23885 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
23886 The database engine to use.
23888 @item @code{name} (default: @code{"patchwork"})
23889 The name of the database to use.
23891 @item @code{user} (default: @code{"httpd"})
23892 The user to connect to the database as.
23894 @item @code{password} (default: @code{""})
23895 The password to use when connecting to the database.
23897 @item @code{host} (default: @code{""})
23898 The host to make the database connection to.
23900 @item @code{port} (default: @code{""})
23901 The port on which to connect to the database.
23906 @subsubheading Mumi
23908 @cindex Mumi, Debbugs Web interface
23909 @cindex Debbugs, Mumi Web interface
23910 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
23911 Web interface to the Debbugs bug tracker, by default for
23912 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
23913 but it also fetches and indexes mail retrieved from Debbugs.
23915 @defvr {Scheme Variable} mumi-service-type
23916 This is the service type for Mumi.
23919 @deftp {Data Type} mumi-configuration
23920 Data type representing the Mumi service configuration. This type has the
23924 @item @code{mumi} (default: @code{mumi})
23925 The Mumi package to use.
23927 @item @code{mailer?} (default: @code{#true})
23928 Whether to enable or disable the mailer component.
23930 @item @code{mumi-configuration-sender}
23931 The email address used as the sender for comments.
23933 @item @code{mumi-configuration-smtp}
23934 A URI to configure the SMTP settings for Mailutils. This could be
23935 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
23936 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
23937 mailutils, GNU@tie{}Mailutils}.
23943 @subsubheading FastCGI
23946 FastCGI is an interface between the front-end and the back-end of a web
23947 service. It is a somewhat legacy facility; new web services should
23948 generally just talk HTTP between the front-end and the back-end.
23949 However there are a number of back-end services such as PHP or the
23950 optimized HTTP Git repository access that use FastCGI, so we have
23951 support for it in Guix.
23953 To use FastCGI, you configure the front-end web server (e.g., nginx) to
23954 dispatch some subset of its requests to the fastcgi backend, which
23955 listens on a local TCP or UNIX socket. There is an intermediary
23956 @code{fcgiwrap} program that sits between the actual backend process and
23957 the web server. The front-end indicates which backend program to run,
23958 passing that information to the @code{fcgiwrap} process.
23960 @defvr {Scheme Variable} fcgiwrap-service-type
23961 A service type for the @code{fcgiwrap} FastCGI proxy.
23964 @deftp {Data Type} fcgiwrap-configuration
23965 Data type representing the configuration of the @code{fcgiwrap} service.
23966 This type has the following parameters:
23968 @item @code{package} (default: @code{fcgiwrap})
23969 The fcgiwrap package to use.
23971 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
23972 The socket on which the @code{fcgiwrap} process should listen, as a
23973 string. Valid @var{socket} values include
23974 @code{unix:@var{/path/to/unix/socket}},
23975 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
23976 @code{tcp6:[@var{ipv6_addr}]:port}.
23978 @item @code{user} (default: @code{fcgiwrap})
23979 @itemx @code{group} (default: @code{fcgiwrap})
23980 The user and group names, as strings, under which to run the
23981 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
23982 the user asks for the specific user or group names @code{fcgiwrap} that
23983 the corresponding user and/or group is present on the system.
23985 It is possible to configure a FastCGI-backed web service to pass HTTP
23986 authentication information from the front-end to the back-end, and to
23987 allow @code{fcgiwrap} to run the back-end process as a corresponding
23988 local user. To enable this capability on the back-end, run
23989 @code{fcgiwrap} as the @code{root} user and group. Note that this
23990 capability also has to be configured on the front-end as well.
23995 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
23996 with some additional features useful for sites of any size.
23998 These features include:
24000 @item Adaptive process spawning
24001 @item Basic statistics (similar to Apache's mod_status)
24002 @item Advanced process management with graceful stop/start
24003 @item Ability to start workers with different uid/gid/chroot/environment
24004 and different php.ini (replaces safe_mode)
24005 @item Stdout & stderr logging
24006 @item Emergency restart in case of accidental opcode cache destruction
24007 @item Accelerated upload support
24008 @item Support for a "slowlog"
24009 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
24010 a special function to finish request & flush all data while continuing to do
24011 something time-consuming (video converting, stats processing, etc.)
24013 ...@: and much more.
24015 @defvr {Scheme Variable} php-fpm-service-type
24016 A Service type for @code{php-fpm}.
24019 @deftp {Data Type} php-fpm-configuration
24020 Data Type for php-fpm service configuration.
24022 @item @code{php} (default: @code{php})
24023 The php package to use.
24024 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
24025 The address on which to accept FastCGI requests. Valid syntaxes are:
24027 @item @code{"ip.add.re.ss:port"}
24028 Listen on a TCP socket to a specific address on a specific port.
24029 @item @code{"port"}
24030 Listen on a TCP socket to all addresses on a specific port.
24031 @item @code{"/path/to/unix/socket"}
24032 Listen on a unix socket.
24035 @item @code{user} (default: @code{php-fpm})
24036 User who will own the php worker processes.
24037 @item @code{group} (default: @code{php-fpm})
24038 Group of the worker processes.
24039 @item @code{socket-user} (default: @code{php-fpm})
24040 User who can speak to the php-fpm socket.
24041 @item @code{socket-group} (default: @code{nginx})
24042 Group that can speak to the php-fpm socket.
24043 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
24044 The process id of the php-fpm process is written to this file
24045 once the service has started.
24046 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
24047 Log for the php-fpm master process.
24048 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
24049 Detailed settings for the php-fpm process manager.
24052 @item @code{<php-fpm-dynamic-process-manager-configuration>}
24053 @item @code{<php-fpm-static-process-manager-configuration>}
24054 @item @code{<php-fpm-on-demand-process-manager-configuration>}
24056 @item @code{display-errors} (default @code{#f})
24057 Determines whether php errors and warning should be sent to clients
24058 and displayed in their browsers.
24059 This is useful for local php development, but a security risk for public sites,
24060 as error messages can reveal passwords and personal data.
24061 @item @code{timezone} (default @code{#f})
24062 Specifies @code{php_admin_value[date.timezone]} parameter.
24063 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
24064 This file will log the @code{stderr} outputs of php worker processes.
24065 Can be set to @code{#f} to disable logging.
24066 @item @code{file} (default @code{#f})
24067 An optional override of the whole configuration.
24068 You can use the @code{mixed-text-file} function or an absolute filepath for it.
24069 @item @code{php-ini-file} (default @code{#f})
24070 An optional override of the default php settings.
24071 It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
24072 You can use the @code{mixed-text-file} function or an absolute filepath for it.
24074 For local development it is useful to set a higher timeout and memory
24075 limit for spawned php processes. This be accomplished with the
24076 following operating system configuration snippet:
24078 (define %local-php-ini
24079 (plain-file "php.ini"
24081 max_execution_time = 1800"))
24085 (services (cons (service php-fpm-service-type
24086 (php-fpm-configuration
24087 (php-ini-file %local-php-ini)))
24091 Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
24092 directives} for comprehensive documentation on the acceptable
24093 @file{php.ini} directives.
24097 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
24098 Data Type for the @code{dynamic} php-fpm process manager. With the
24099 @code{dynamic} process manager, spare worker processes are kept around
24100 based on it's configured limits.
24102 @item @code{max-children} (default: @code{5})
24103 Maximum of worker processes.
24104 @item @code{start-servers} (default: @code{2})
24105 How many worker processes should be started on start-up.
24106 @item @code{min-spare-servers} (default: @code{1})
24107 How many spare worker processes should be kept around at minimum.
24108 @item @code{max-spare-servers} (default: @code{3})
24109 How many spare worker processes should be kept around at maximum.
24113 @deftp {Data type} php-fpm-static-process-manager-configuration
24114 Data Type for the @code{static} php-fpm process manager. With the
24115 @code{static} process manager, an unchanging number of worker processes
24118 @item @code{max-children} (default: @code{5})
24119 Maximum of worker processes.
24123 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
24124 Data Type for the @code{on-demand} php-fpm process manager. With the
24125 @code{on-demand} process manager, worker processes are only created as
24128 @item @code{max-children} (default: @code{5})
24129 Maximum of worker processes.
24130 @item @code{process-idle-timeout} (default: @code{10})
24131 The time in seconds after which a process with no requests is killed.
24136 @deffn {Scheme Procedure} nginx-php-location @
24137 [#:nginx-package nginx] @
24138 [socket (string-append "/var/run/php" @
24139 (version-major (package-version php)) @
24141 A helper function to quickly add php to an @code{nginx-server-configuration}.
24144 A simple services setup for nginx with php can look like this:
24146 (services (cons* (service dhcp-client-service-type)
24147 (service php-fpm-service-type)
24148 (service nginx-service-type
24149 (nginx-server-configuration
24150 (server-name '("example.com"))
24151 (root "/srv/http/")
24153 (list (nginx-php-location)))
24155 (ssl-certificate #f)
24156 (ssl-certificate-key #f)))
24160 @cindex cat-avatar-generator
24161 The cat avatar generator is a simple service to demonstrate the use of php-fpm
24162 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
24163 the hash of a user's email address.
24165 @deffn {Scheme Procedure} cat-avatar-generator-service @
24166 [#:cache-dir "/var/cache/cat-avatar-generator"] @
24167 [#:package cat-avatar-generator] @
24168 [#:configuration (nginx-server-configuration)]
24169 Returns an nginx-server-configuration that inherits @code{configuration}. It
24170 extends the nginx configuration to add a server block that serves @code{package},
24171 a version of cat-avatar-generator. During execution, cat-avatar-generator will
24172 be able to use @code{cache-dir} as its cache directory.
24175 A simple setup for cat-avatar-generator can look like this:
24177 (services (cons* (cat-avatar-generator-service
24179 (nginx-server-configuration
24180 (server-name '("example.com"))))
24185 @subsubheading Hpcguix-web
24187 @cindex hpcguix-web
24188 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
24189 program is a customizable web interface to browse Guix packages,
24190 initially designed for users of high-performance computing (HPC)
24193 @defvr {Scheme Variable} hpcguix-web-service-type
24194 The service type for @code{hpcguix-web}.
24197 @deftp {Data Type} hpcguix-web-configuration
24198 Data type for the hpcguix-web service configuration.
24202 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
24203 configuration. The main items available in this spec are:
24206 @item @code{title-prefix} (default: @code{"hpcguix | "})
24207 The page title prefix.
24209 @item @code{guix-command} (default: @code{"guix"})
24210 The @command{guix} command.
24212 @item @code{package-filter-proc} (default: @code{(const #t)})
24213 A procedure specifying how to filter packages that are displayed.
24215 @item @code{package-page-extension-proc} (default: @code{(const '())})
24216 Extension package for @code{hpcguix-web}.
24218 @item @code{menu} (default: @code{'()})
24219 Additional entry in page @code{menu}.
24221 @item @code{channels} (default: @code{%default-channels})
24222 List of channels from which the package list is built (@pxref{Channels}).
24224 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
24225 The expiration time, in seconds, after which the package list is rebuilt from
24226 the latest instances of the given channels.
24229 See the hpcguix-web repository for a
24230 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
24233 @item @code{package} (default: @code{hpcguix-web})
24234 The hpcguix-web package to use.
24238 A typical hpcguix-web service declaration looks like this:
24241 (service hpcguix-web-service-type
24242 (hpcguix-web-configuration
24244 #~(define site-config
24245 (hpcweb-configuration
24246 (title-prefix "Guix-HPC - ")
24247 (menu '(("/about" "ABOUT"))))))))
24251 The hpcguix-web service periodically updates the package list it publishes by
24252 pulling channels from Git. To that end, it needs to access X.509 certificates
24253 so that it can authenticate Git servers when communicating over HTTPS, and it
24254 assumes that @file{/etc/ssl/certs} contains those certificates.
24256 Thus, make sure to add @code{nss-certs} or another certificate package to the
24257 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
24258 more information on X.509 certificates.
24261 @subsubheading gmnisrv
24264 The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
24265 simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
24267 @deffn {Scheme Variable} gmnisrv-service-type
24268 This is the type of the gmnisrv service, whose value should be a
24269 @code{gmnisrv-configuration} object, as in this example:
24272 (service gmnisrv-service-type
24273 (gmnisrv-configuration
24274 (config-file (local-file "./my-gmnisrv.ini"))))
24278 @deftp {Data Type} gmnisrv-configuration
24279 Data type representing the configuration of gmnisrv.
24282 @item @code{package} (default: @var{gmnisrv})
24283 Package object of the gmnisrv server.
24285 @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
24286 File-like object of the gmnisrv configuration file to use. The default
24287 configuration listens on port 1965 and serves files from
24288 @file{/srv/gemini}. Certificates are stored in
24289 @file{/var/lib/gemini/certs}. For more information, run @command{man
24290 gmnisrv} and @command{man gmnisrv.ini}.
24295 @node Certificate Services
24296 @subsection Certificate Services
24299 @cindex HTTP, HTTPS
24300 @cindex Let's Encrypt
24301 @cindex TLS certificates
24302 The @code{(gnu services certbot)} module provides a service to
24303 automatically obtain a valid TLS certificate from the Let's Encrypt
24304 certificate authority. These certificates can then be used to serve
24305 content securely over HTTPS or other TLS-based protocols, with the
24306 knowledge that the client will be able to verify the server's
24309 @url{https://letsencrypt.org/, Let's Encrypt} provides the
24310 @code{certbot} tool to automate the certification process. This tool
24311 first securely generates a key on the server. It then makes a request
24312 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
24313 checks that the request originates from the host in question by using a
24314 challenge-response protocol, requiring the server to provide its
24315 response over HTTP. If that protocol completes successfully, the CA
24316 signs the key, resulting in a certificate. That certificate is valid
24317 for a limited period of time, and therefore to continue to provide TLS
24318 services, the server needs to periodically ask the CA to renew its
24321 The certbot service automates this process: the initial key
24322 generation, the initial certification request to the Let's Encrypt
24323 service, the web server challenge/response integration, writing the
24324 certificate to disk, the automated periodic renewals, and the deployment
24325 tasks associated with the renewal (e.g.@: reloading services, copying keys
24326 with different permissions).
24328 Certbot is run twice a day, at a random minute within the hour. It
24329 won't do anything until your certificates are due for renewal or
24330 revoked, but running it regularly would give your service a chance of
24331 staying online in case a Let's Encrypt-initiated revocation happened for
24334 By using this service, you agree to the ACME Subscriber Agreement, which
24335 can be found there:
24336 @url{https://acme-v01.api.letsencrypt.org/directory}.
24338 @defvr {Scheme Variable} certbot-service-type
24339 A service type for the @code{certbot} Let's Encrypt client. Its value
24340 must be a @code{certbot-configuration} record as in this example:
24343 (define %nginx-deploy-hook
24345 "nginx-deploy-hook"
24346 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
24347 (kill pid SIGHUP))))
24349 (service certbot-service-type
24350 (certbot-configuration
24351 (email "foo@@example.net")
24354 (certificate-configuration
24355 (domains '("example.net" "www.example.net"))
24356 (deploy-hook %nginx-deploy-hook))
24357 (certificate-configuration
24358 (domains '("bar.example.net")))))))
24361 See below for details about @code{certbot-configuration}.
24364 @deftp {Data Type} certbot-configuration
24365 Data type representing the configuration of the @code{certbot} service.
24366 This type has the following parameters:
24369 @item @code{package} (default: @code{certbot})
24370 The certbot package to use.
24372 @item @code{webroot} (default: @code{/var/www})
24373 The directory from which to serve the Let's Encrypt challenge/response
24376 @item @code{certificates} (default: @code{()})
24377 A list of @code{certificates-configuration}s for which to generate
24378 certificates and request signatures. Each certificate has a @code{name}
24379 and several @code{domains}.
24381 @item @code{email} (default: @code{#f})
24382 Optional email address used for registration and recovery contact.
24383 Setting this is encouraged as it allows you to receive important
24384 notifications about the account and issued certificates.
24386 @item @code{server} (default: @code{#f})
24387 Optional URL of ACME server. Setting this overrides certbot's default,
24388 which is the Let's Encrypt server.
24390 @item @code{rsa-key-size} (default: @code{2048})
24391 Size of the RSA key.
24393 @item @code{default-location} (default: @i{see below})
24394 The default @code{nginx-location-configuration}. Because @code{certbot}
24395 needs to be able to serve challenges and responses, it needs to be able
24396 to run a web server. It does so by extending the @code{nginx} web
24397 service with an @code{nginx-server-configuration} listening on the
24398 @var{domains} on port 80, and which has a
24399 @code{nginx-location-configuration} for the @code{/.well-known/} URI
24400 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
24401 these nginx configuration data types.
24403 Requests to other URL paths will be matched by the
24404 @code{default-location}, which if present is added to all
24405 @code{nginx-server-configuration}s.
24407 By default, the @code{default-location} will issue a redirect from
24408 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
24409 you to define what to serve on your site via @code{https}.
24411 Pass @code{#f} to not issue a default location.
24415 @deftp {Data Type} certificate-configuration
24416 Data type representing the configuration of a certificate.
24417 This type has the following parameters:
24420 @item @code{name} (default: @i{see below})
24421 This name is used by Certbot for housekeeping and in file paths; it
24422 doesn't affect the content of the certificate itself. To see
24423 certificate names, run @code{certbot certificates}.
24425 Its default is the first provided domain.
24427 @item @code{domains} (default: @code{()})
24428 The first domain provided will be the subject CN of the certificate, and
24429 all domains will be Subject Alternative Names on the certificate.
24431 @item @code{challenge} (default: @code{#f})
24432 The challenge type that has to be run by certbot. If @code{#f} is specified,
24433 default to the HTTP challenge. If a value is specified, defaults to the
24434 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
24435 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
24436 and gives Let's Encrypt permission to log the public IP address of the
24437 requesting machine.
24439 @item @code{authentication-hook} (default: @code{#f})
24440 Command to be run in a shell once for each certificate challenge to be
24441 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
24442 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
24443 contains the validation string and @code{$CERTBOT_TOKEN} contains the
24444 file name of the resource requested when performing an HTTP-01 challenge.
24446 @item @code{cleanup-hook} (default: @code{#f})
24447 Command to be run in a shell once for each certificate challenge that
24448 have been answered by the @code{auth-hook}. For this command, the shell
24449 variables available in the @code{auth-hook} script are still available, and
24450 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
24451 of the @code{auth-hook} script.
24453 @item @code{deploy-hook} (default: @code{#f})
24454 Command to be run in a shell once for each successfully issued
24455 certificate. For this command, the shell variable
24456 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
24457 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
24458 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
24459 contain a space-delimited list of renewed certificate domains (for
24460 example, @samp{"example.com www.example.com"}.
24465 For each @code{certificate-configuration}, the certificate is saved to
24466 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
24467 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
24469 @subsection DNS Services
24470 @cindex DNS (domain name system)
24471 @cindex domain name system (DNS)
24473 The @code{(gnu services dns)} module provides services related to the
24474 @dfn{domain name system} (DNS). It provides a server service for hosting
24475 an @emph{authoritative} DNS server for multiple zones, slave or master.
24476 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
24477 caching and forwarding DNS server for the LAN, which uses
24478 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
24480 @subsubheading Knot Service
24482 An example configuration of an authoritative server for two zones, one master
24486 (define-zone-entries example.org.zone
24487 ;; Name TTL Class Type Data
24488 ("@@" "" "IN" "A" "127.0.0.1")
24489 ("@@" "" "IN" "NS" "ns")
24490 ("ns" "" "IN" "A" "127.0.0.1"))
24492 (define master-zone
24493 (knot-zone-configuration
24494 (domain "example.org")
24496 (origin "example.org")
24497 (entries example.org.zone)))))
24500 (knot-zone-configuration
24501 (domain "plop.org")
24502 (dnssec-policy "default")
24503 (master (list "plop-master"))))
24505 (define plop-master
24506 (knot-remote-configuration
24508 (address (list "208.76.58.171"))))
24512 (services (cons* (service knot-service-type
24513 (knot-configuration
24514 (remotes (list plop-master))
24515 (zones (list master-zone slave-zone))))
24520 @deffn {Scheme Variable} knot-service-type
24521 This is the type for the Knot DNS server.
24523 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
24524 zones, that is to say domain names you would buy from a registrar. This server
24525 is not a resolver, meaning that it can only resolve names for which it is
24526 authoritative. This server can be configured to serve zones as a master server
24527 or a slave server as a per-zone basis. Slave zones will get their data from
24528 masters, and will serve it as an authoritative server. From the point of view
24529 of a resolver, there is no difference between master and slave.
24531 The following data types are used to configure the Knot DNS server:
24534 @deftp {Data Type} knot-key-configuration
24535 Data type representing a key.
24536 This type has the following parameters:
24539 @item @code{id} (default: @code{""})
24540 An identifier for other configuration fields to refer to this key. IDs must
24541 be unique and must not be empty.
24543 @item @code{algorithm} (default: @code{#f})
24544 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
24545 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
24546 and @code{'hmac-sha512}.
24548 @item @code{secret} (default: @code{""})
24549 The secret key itself.
24554 @deftp {Data Type} knot-acl-configuration
24555 Data type representing an Access Control List (ACL) configuration.
24556 This type has the following parameters:
24559 @item @code{id} (default: @code{""})
24560 An identifier for other configuration fields to refer to this key. IDs must be
24561 unique and must not be empty.
24563 @item @code{address} (default: @code{'()})
24564 An ordered list of IP addresses, network subnets, or network ranges represented
24565 with strings. The query must match one of them. Empty value means that
24566 address match is not required.
24568 @item @code{key} (default: @code{'()})
24569 An ordered list of references to keys represented with strings. The string
24570 must match a key ID defined in a @code{knot-key-configuration}. No key means
24571 that a key is not require to match that ACL.
24573 @item @code{action} (default: @code{'()})
24574 An ordered list of actions that are permitted or forbidden by this ACL. Possible
24575 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
24576 and @code{'update}.
24578 @item @code{deny?} (default: @code{#f})
24579 When true, the ACL defines restrictions. Listed actions are forbidden. When
24580 false, listed actions are allowed.
24585 @deftp {Data Type} zone-entry
24586 Data type representing a record entry in a zone file.
24587 This type has the following parameters:
24590 @item @code{name} (default: @code{"@@"})
24591 The name of the record. @code{"@@"} refers to the origin of the zone. Names
24592 are relative to the origin of the zone. For example, in the @code{example.org}
24593 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
24594 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
24595 refers to @code{ns.example.org}.
24597 @item @code{ttl} (default: @code{""})
24598 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
24600 @item @code{class} (default: @code{"IN"})
24601 The class of the record. Knot currently supports only @code{"IN"} and
24602 partially @code{"CH"}.
24604 @item @code{type} (default: @code{"A"})
24605 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
24606 address), NS (Name Server) and MX (Mail eXchange). Many other types are
24609 @item @code{data} (default: @code{""})
24610 The data contained in the record. For instance an IP address associated with
24611 an A record, or a domain name associated with an NS record. Remember that
24612 domain names are relative to the origin unless they end with a dot.
24617 @deftp {Data Type} zone-file
24618 Data type representing the content of a zone file.
24619 This type has the following parameters:
24622 @item @code{entries} (default: @code{'()})
24623 The list of entries. The SOA record is taken care of, so you don't need to
24624 put it in the list of entries. This list should probably contain an entry
24625 for your primary authoritative DNS server. Other than using a list of entries
24626 directly, you can use @code{define-zone-entries} to define a object containing
24627 the list of entries more easily, that you can later pass to the @code{entries}
24628 field of the @code{zone-file}.
24630 @item @code{origin} (default: @code{""})
24631 The name of your zone. This parameter cannot be empty.
24633 @item @code{ns} (default: @code{"ns"})
24634 The domain of your primary authoritative DNS server. The name is relative to
24635 the origin, unless it ends with a dot. It is mandatory that this primary
24636 DNS server corresponds to an NS record in the zone and that it is associated
24637 to an IP address in the list of entries.
24639 @item @code{mail} (default: @code{"hostmaster"})
24640 An email address people can contact you at, as the owner of the zone. This
24641 is translated as @code{<mail>@@<origin>}.
24643 @item @code{serial} (default: @code{1})
24644 The serial number of the zone. As this is used to keep track of changes by
24645 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
24646 Always increment it when you make a change in your zone.
24648 @item @code{refresh} (default: @code{(* 2 24 3600)})
24649 The frequency at which slaves will do a zone transfer. This value is a number
24650 of seconds. It can be computed by multiplications or with
24651 @code{(string->duration)}.
24653 @item @code{retry} (default: @code{(* 15 60)})
24654 The period after which a slave will retry to contact its master when it fails
24655 to do so a first time.
24657 @item @code{expiry} (default: @code{(* 14 24 3600)})
24658 Default TTL of records. Existing records are considered correct for at most
24659 this amount of time. After this period, resolvers will invalidate their cache
24660 and check again that it still exists.
24662 @item @code{nx} (default: @code{3600})
24663 Default TTL of inexistant records. This delay is usually short because you want
24664 your new domains to reach everyone quickly.
24669 @deftp {Data Type} knot-remote-configuration
24670 Data type representing a remote configuration.
24671 This type has the following parameters:
24674 @item @code{id} (default: @code{""})
24675 An identifier for other configuration fields to refer to this remote. IDs must
24676 be unique and must not be empty.
24678 @item @code{address} (default: @code{'()})
24679 An ordered list of destination IP addresses. Addresses are tried in sequence.
24680 An optional port can be given with the @@ separator. For instance:
24681 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
24683 @item @code{via} (default: @code{'()})
24684 An ordered list of source IP addresses. An empty list will have Knot choose
24685 an appropriate source IP. An optional port can be given with the @@ separator.
24686 The default is to choose at random.
24688 @item @code{key} (default: @code{#f})
24689 A reference to a key, that is a string containing the identifier of a key
24690 defined in a @code{knot-key-configuration} field.
24695 @deftp {Data Type} knot-keystore-configuration
24696 Data type representing a keystore to hold dnssec keys.
24697 This type has the following parameters:
24700 @item @code{id} (default: @code{""})
24701 The id of the keystore. It must not be empty.
24703 @item @code{backend} (default: @code{'pem})
24704 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
24706 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
24707 The configuration string of the backend. An example for the PKCS#11 is:
24708 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
24709 For the pem backend, the string represents a path in the file system.
24714 @deftp {Data Type} knot-policy-configuration
24715 Data type representing a dnssec policy. Knot DNS is able to automatically
24716 sign your zones. It can either generate and manage your keys automatically or
24717 use keys that you generate.
24719 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
24720 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
24721 zone. In order to be trusted, the KSK needs to be present in the parent zone
24722 (usually a top-level domain). If your registrar supports dnssec, you will
24723 have to send them your KSK's hash so they can add a DS record in their zone.
24724 This is not automated and need to be done each time you change your KSK.
24726 The policy also defines the lifetime of keys. Usually, ZSK can be changed
24727 easily and use weaker cryptographic functions (they use lower parameters) in
24728 order to sign records quickly, so they are changed often. The KSK however
24729 requires manual interaction with the registrar, so they are changed less often
24730 and use stronger parameters because they sign only one record.
24732 This type has the following parameters:
24735 @item @code{id} (default: @code{""})
24736 The id of the policy. It must not be empty.
24738 @item @code{keystore} (default: @code{"default"})
24739 A reference to a keystore, that is a string containing the identifier of a
24740 keystore defined in a @code{knot-keystore-configuration} field. The
24741 @code{"default"} identifier means the default keystore (a kasp database that
24742 was setup by this service).
24744 @item @code{manual?} (default: @code{#f})
24745 Whether the key management is manual or automatic.
24747 @item @code{single-type-signing?} (default: @code{#f})
24748 When @code{#t}, use the Single-Type Signing Scheme.
24750 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
24751 An algorithm of signing keys and issued signatures.
24753 @item @code{ksk-size} (default: @code{256})
24754 The length of the KSK. Note that this value is correct for the default
24755 algorithm, but would be unsecure for other algorithms.
24757 @item @code{zsk-size} (default: @code{256})
24758 The length of the ZSK. Note that this value is correct for the default
24759 algorithm, but would be unsecure for other algorithms.
24761 @item @code{dnskey-ttl} (default: @code{'default})
24762 The TTL value for DNSKEY records added into zone apex. The special
24763 @code{'default} value means same as the zone SOA TTL.
24765 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
24766 The period between ZSK publication and the next rollover initiation.
24768 @item @code{propagation-delay} (default: @code{(* 24 3600)})
24769 An extra delay added for each key rollover step. This value should be high
24770 enough to cover propagation of data from the master server to all slaves.
24772 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
24773 A validity period of newly issued signatures.
24775 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
24776 A period how long before a signature expiration the signature will be refreshed.
24778 @item @code{nsec3?} (default: @code{#f})
24779 When @code{#t}, NSEC3 will be used instead of NSEC.
24781 @item @code{nsec3-iterations} (default: @code{5})
24782 The number of additional times the hashing is performed.
24784 @item @code{nsec3-salt-length} (default: @code{8})
24785 The length of a salt field in octets, which is appended to the original owner
24786 name before hashing.
24788 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
24789 The validity period of newly issued salt field.
24794 @deftp {Data Type} knot-zone-configuration
24795 Data type representing a zone served by Knot.
24796 This type has the following parameters:
24799 @item @code{domain} (default: @code{""})
24800 The domain served by this configuration. It must not be empty.
24802 @item @code{file} (default: @code{""})
24803 The file where this zone is saved. This parameter is ignored by master zones.
24804 Empty means default location that depends on the domain name.
24806 @item @code{zone} (default: @code{(zone-file)})
24807 The content of the zone file. This parameter is ignored by slave zones. It
24808 must contain a zone-file record.
24810 @item @code{master} (default: @code{'()})
24811 A list of master remotes. When empty, this zone is a master. When set, this
24812 zone is a slave. This is a list of remotes identifiers.
24814 @item @code{ddns-master} (default: @code{#f})
24815 The main master. When empty, it defaults to the first master in the list of
24818 @item @code{notify} (default: @code{'()})
24819 A list of slave remote identifiers.
24821 @item @code{acl} (default: @code{'()})
24822 A list of acl identifiers.
24824 @item @code{semantic-checks?} (default: @code{#f})
24825 When set, this adds more semantic checks to the zone.
24827 @item @code{disable-any?} (default: @code{#f})
24828 When set, this forbids queries of the ANY type.
24830 @item @code{zonefile-sync} (default: @code{0})
24831 The delay between a modification in memory and on disk. 0 means immediate
24834 @item @code{zonefile-load} (default: @code{#f})
24835 The way the zone file contents are applied during zone load. Possible values
24839 @item @code{#f} for using the default value from Knot,
24840 @item @code{'none} for not using the zone file at all,
24841 @item @code{'difference} for computing the difference between already available
24842 contents and zone contents and applying it to the current zone contents,
24843 @item @code{'difference-no-serial} for the same as @code{'difference}, but
24844 ignoring the SOA serial in the zone file, while the server takes care of it
24846 @item @code{'whole} for loading zone contents from the zone file.
24849 @item @code{journal-content} (default: @code{#f})
24850 The way the journal is used to store zone and its changes. Possible values
24851 are @code{'none} to not use it at all, @code{'changes} to store changes and
24852 @code{'all} to store contents. @code{#f} does not set this option, so the
24853 default value from Knot is used.
24855 @item @code{max-journal-usage} (default: @code{#f})
24856 The maximum size for the journal on disk. @code{#f} does not set this option,
24857 so the default value from Knot is used.
24859 @item @code{max-journal-depth} (default: @code{#f})
24860 The maximum size of the history. @code{#f} does not set this option, so the
24861 default value from Knot is used.
24863 @item @code{max-zone-size} (default: @code{#f})
24864 The maximum size of the zone file. This limit is enforced for incoming
24865 transfer and updates. @code{#f} does not set this option, so the default
24866 value from Knot is used.
24868 @item @code{dnssec-policy} (default: @code{#f})
24869 A reference to a @code{knot-policy-configuration} record, or the special
24870 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
24873 @item @code{serial-policy} (default: @code{'increment})
24874 A policy between @code{'increment} and @code{'unixtime}.
24879 @deftp {Data Type} knot-configuration
24880 Data type representing the Knot configuration.
24881 This type has the following parameters:
24884 @item @code{knot} (default: @code{knot})
24887 @item @code{run-directory} (default: @code{"/var/run/knot"})
24888 The run directory. This directory will be used for pid file and sockets.
24890 @item @code{includes} (default: @code{'()})
24891 A list of strings or file-like objects denoting other files that must be
24892 included at the top of the configuration file.
24894 @cindex secrets, Knot service
24895 This can be used to manage secrets out-of-band. For example, secret
24896 keys may be stored in an out-of-band file not managed by Guix, and
24897 thus not visible in @file{/gnu/store}---e.g., you could store secret
24898 key configuration in @file{/etc/knot/secrets.conf} and add this file
24899 to the @code{includes} list.
24901 One can generate a secret tsig key (for nsupdate and zone transfers with the
24902 keymgr command from the knot package. Note that the package is not automatically
24903 installed by the service. The following example shows how to generate a new
24907 keymgr -t mysecret > /etc/knot/secrets.conf
24908 chmod 600 /etc/knot/secrets.conf
24911 Also note that the generated key will be named @var{mysecret}, so it is the
24912 name that needs to be used in the @var{key} field of the
24913 @code{knot-acl-configuration} record and in other places that need to refer
24916 It can also be used to add configuration not supported by this interface.
24918 @item @code{listen-v4} (default: @code{"0.0.0.0"})
24919 An ip address on which to listen.
24921 @item @code{listen-v6} (default: @code{"::"})
24922 An ip address on which to listen.
24924 @item @code{listen-port} (default: @code{53})
24925 A port on which to listen.
24927 @item @code{keys} (default: @code{'()})
24928 The list of knot-key-configuration used by this configuration.
24930 @item @code{acls} (default: @code{'()})
24931 The list of knot-acl-configuration used by this configuration.
24933 @item @code{remotes} (default: @code{'()})
24934 The list of knot-remote-configuration used by this configuration.
24936 @item @code{zones} (default: @code{'()})
24937 The list of knot-zone-configuration used by this configuration.
24942 @subsubheading Knot Resolver Service
24944 @deffn {Scheme Variable} knot-resolver-service-type
24945 This is the type of the knot resolver service, whose value should be
24946 an @code{knot-resolver-configuration} object as in this example:
24949 (service knot-resolver-service-type
24950 (knot-resolver-configuration
24951 (kresd-config-file (plain-file "kresd.conf" "
24952 net.listen('192.168.0.1', 5353)
24953 user('knot-resolver', 'knot-resolver')
24954 modules = @{ 'hints > iterate', 'stats', 'predict' @}
24955 cache.size = 100 * MB
24959 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
24962 @deftp {Data Type} knot-resolver-configuration
24963 Data type representing the configuration of knot-resolver.
24966 @item @code{package} (default: @var{knot-resolver})
24967 Package object of the knot DNS resolver.
24969 @item @code{kresd-config-file} (default: %kresd.conf)
24970 File-like object of the kresd configuration file to use, by default it
24971 will listen on @code{127.0.0.1} and @code{::1}.
24973 @item @code{garbage-collection-interval} (default: 1000)
24974 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
24980 @subsubheading Dnsmasq Service
24982 @deffn {Scheme Variable} dnsmasq-service-type
24983 This is the type of the dnsmasq service, whose value should be an
24984 @code{dnsmasq-configuration} object as in this example:
24987 (service dnsmasq-service-type
24988 (dnsmasq-configuration
24990 (servers '("192.168.1.1"))))
24994 @deftp {Data Type} dnsmasq-configuration
24995 Data type representing the configuration of dnsmasq.
24998 @item @code{package} (default: @var{dnsmasq})
24999 Package object of the dnsmasq server.
25001 @item @code{no-hosts?} (default: @code{#f})
25002 When true, don't read the hostnames in /etc/hosts.
25004 @item @code{port} (default: @code{53})
25005 The port to listen on. Setting this to zero completely disables DNS
25006 responses, leaving only DHCP and/or TFTP functions.
25008 @item @code{local-service?} (default: @code{#t})
25009 Accept DNS queries only from hosts whose address is on a local subnet,
25010 ie a subnet for which an interface exists on the server.
25012 @item @code{listen-addresses} (default: @code{'()})
25013 Listen on the given IP addresses.
25015 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
25016 The file to read the IP address of the upstream nameservers from.
25018 @item @code{no-resolv?} (default: @code{#f})
25019 When true, don't read @var{resolv-file}.
25021 @item @code{servers} (default: @code{'()})
25022 Specify IP address of upstream servers directly.
25024 @item @code{addresses} (default: @code{'()})
25025 For each entry, specify an IP address to return for any host in the
25026 given domains. Queries in the domains are never forwarded and always
25027 replied to with the specified IP address.
25029 This is useful for redirecting hosts locally, for example:
25032 (service dnsmasq-service-type
25033 (dnsmasq-configuration
25035 '(; Redirect to a local web-server.
25036 "/example.org/127.0.0.1"
25037 ; Redirect subdomain to a specific IP.
25038 "/subdomain.example.org/192.168.1.42"))))
25041 Note that rules in @file{/etc/hosts} take precedence over this.
25043 @item @code{cache-size} (default: @code{150})
25044 Set the size of dnsmasq's cache. Setting the cache size to zero
25047 @item @code{negative-cache?} (default: @code{#t})
25048 When false, disable negative caching.
25050 @item @code{tftp-enable?} (default: @code{#f})
25051 Whether to enable the built-in TFTP server.
25053 @item @code{tftp-no-fail?} (default: @code{#f})
25054 If true, does not fail dnsmasq if the TFTP server could not start up.
25056 @item @code{tftp-single-port?} (default: @code{#f})
25057 Whether to use only one single port for TFTP.
25059 @item @code{tftp-secure?} (default: @code{#f})
25060 If true, only files owned by the user running the dnsmasq process are accessible.
25062 If dnsmasq is being run as root, different rules apply:
25063 @code{tftp-secure?} has no effect, but only files which have the
25064 world-readable bit set are accessible.
25066 @item @code{tftp-max} (default: @code{#f})
25067 If set, sets the maximal number of concurrent connections allowed.
25069 @item @code{tftp-mtu} (default: @code{#f})
25070 If set, sets the MTU for TFTP packets to that value.
25072 @item @code{tftp-no-blocksize?} (default: @code{#f})
25073 If true, stops the TFTP server from negotiating the blocksize with a client.
25075 @item @code{tftp-lowercase?} (default: @code{#f})
25076 Whether to convert all filenames in TFTP requests to lowercase.
25078 @item @code{tftp-port-range} (default: @code{#f})
25079 If set, fixes the dynamical ports (one per client) to the given range
25080 (@code{"<start>,<end>"}).
25082 @item @code{tftp-root} (default: @code{/var/empty,lo})
25083 Look for files to transfer using TFTP relative to the given directory.
25084 When this is set, TFTP paths which include @samp{..} are rejected, to stop clients
25085 getting outside the specified root. Absolute paths (starting with @samp{/}) are
25086 allowed, but they must be within the TFTP-root. If the optional interface
25087 argument is given, the directory is only used for TFTP requests via that
25090 @item @code{tftp-unique-root} (default: @code{#f})
25091 If set, add the IP or hardware address of the TFTP client as a path component
25092 on the end of the TFTP-root. Only valid if a TFTP root is set and the
25093 directory exists. Defaults to adding IP address (in standard dotted-quad
25096 For instance, if @option{--tftp-root} is @samp{/tftp} and client
25097 @samp{1.2.3.4} requests file @file{myfile} then the effective path will
25098 be @file{/tftp/1.2.3.4/myfile} if @file{/tftp/1.2.3.4} exists or
25099 @file{/tftp/myfile} otherwise. When @samp{=mac} is specified it will
25100 append the MAC address instead, using lowercase zero padded digits
25101 separated by dashes, e.g.: @samp{01-02-03-04-aa-bb}. Note that
25102 resolving MAC addresses is only possible if the client is in the local
25103 network or obtained a DHCP lease from dnsmasq.
25108 @subsubheading ddclient Service
25111 The ddclient service described below runs the ddclient daemon, which takes
25112 care of automatically updating DNS entries for service providers such as
25113 @uref{https://dyn.com/dns/, Dyn}.
25115 The following example show instantiates the service with its default
25119 (service ddclient-service-type)
25122 Note that ddclient needs to access credentials that are stored in a
25123 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
25124 @code{secret-file} below). You are expected to create this file manually, in
25125 an ``out-of-band'' fashion (you @emph{could} make this file part of the
25126 service configuration, for instance by using @code{plain-file}, but it will be
25127 world-readable @i{via} @file{/gnu/store}). See the examples in the
25128 @file{share/ddclient} directory of the @code{ddclient} package.
25130 @c %start of fragment
25132 Available @code{ddclient-configuration} fields are:
25134 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
25135 The ddclient package.
25139 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
25140 The period after which ddclient will retry to check IP and domain name.
25142 Defaults to @samp{300}.
25146 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
25147 Use syslog for the output.
25149 Defaults to @samp{#t}.
25153 @deftypevr {@code{ddclient-configuration} parameter} string mail
25156 Defaults to @samp{"root"}.
25160 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
25161 Mail failed update to user.
25163 Defaults to @samp{"root"}.
25167 @deftypevr {@code{ddclient-configuration} parameter} string pid
25168 The ddclient PID file.
25170 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
25174 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
25175 Enable SSL support.
25177 Defaults to @samp{#t}.
25181 @deftypevr {@code{ddclient-configuration} parameter} string user
25182 Specifies the user name or ID that is used when running ddclient
25185 Defaults to @samp{"ddclient"}.
25189 @deftypevr {@code{ddclient-configuration} parameter} string group
25190 Group of the user who will run the ddclient program.
25192 Defaults to @samp{"ddclient"}.
25196 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
25197 Secret file which will be appended to @file{ddclient.conf} file. This
25198 file contains credentials for use by ddclient. You are expected to
25199 create it manually.
25201 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
25205 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
25206 Extra options will be appended to @file{ddclient.conf} file.
25208 Defaults to @samp{()}.
25213 @c %end of fragment
25217 @subsection VPN Services
25218 @cindex VPN (virtual private network)
25219 @cindex virtual private network (VPN)
25221 The @code{(gnu services vpn)} module provides services related to
25222 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
25223 your machine to connect to a VPN, and a @emph{server} service for your machine
25224 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
25226 @deffn {Scheme Procedure} openvpn-client-service @
25227 [#:config (openvpn-client-configuration)]
25229 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
25232 @deffn {Scheme Procedure} openvpn-server-service @
25233 [#:config (openvpn-server-configuration)]
25235 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
25237 Both can be run simultaneously.
25240 @c %automatically generated documentation
25242 Available @code{openvpn-client-configuration} fields are:
25244 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
25245 The OpenVPN package.
25249 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
25250 The OpenVPN pid file.
25252 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
25256 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
25257 The protocol (UDP or TCP) used to open a channel between clients and
25260 Defaults to @samp{udp}.
25264 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
25265 The device type used to represent the VPN connection.
25267 Defaults to @samp{tun}.
25271 If you do not have some of these files (eg.@: you use a username and
25272 password), you can disable any of the following three fields by setting
25273 it to @code{'disabled}.
25275 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string ca
25276 The certificate authority to check connections against.
25278 Defaults to @samp{"/etc/openvpn/ca.crt"}.
25282 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string cert
25283 The certificate of the machine the daemon is running on. It should be
25284 signed by the authority given in @code{ca}.
25286 Defaults to @samp{"/etc/openvpn/client.crt"}.
25290 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string key
25291 The key of the machine the daemon is running on. It must be the key whose
25292 certificate is @code{cert}.
25294 Defaults to @samp{"/etc/openvpn/client.key"}.
25298 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
25299 Whether to use the lzo compression algorithm.
25301 Defaults to @samp{#t}.
25305 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
25306 Don't re-read key files across SIGUSR1 or --ping-restart.
25308 Defaults to @samp{#t}.
25312 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
25313 Don't close and reopen TUN/TAP device or run up/down scripts across
25314 SIGUSR1 or --ping-restart restarts.
25316 Defaults to @samp{#t}.
25320 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
25321 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
25322 poll/epoll/select prior to the write operation.
25324 Defaults to @samp{#f}.
25327 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
25330 Defaults to @samp{3}.
25334 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
25335 Add an additional layer of HMAC authentication on top of the TLS control
25336 channel to protect against DoS attacks.
25338 Defaults to @samp{#f}.
25342 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
25343 Authenticate with server using username/password. The option is a file
25344 containing username/password on 2 lines. Do not use a file-like object as it
25345 would be added to the store and readable by any user.
25347 Defaults to @samp{'disabled}.
25350 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
25351 Whether to check the server certificate has server usage extension.
25353 Defaults to @samp{#t}.
25357 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
25358 Bind to a specific local port number.
25360 Defaults to @samp{#f}.
25364 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
25365 Retry resolving server address.
25367 Defaults to @samp{#t}.
25371 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
25372 A list of remote servers to connect to.
25374 Defaults to @samp{()}.
25376 Available @code{openvpn-remote-configuration} fields are:
25378 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
25381 Defaults to @samp{"my-server"}.
25385 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
25386 Port number the server listens to.
25388 Defaults to @samp{1194}.
25393 @c %end of automatic openvpn-client documentation
25395 @c %automatically generated documentation
25397 Available @code{openvpn-server-configuration} fields are:
25399 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
25400 The OpenVPN package.
25404 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
25405 The OpenVPN pid file.
25407 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
25411 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
25412 The protocol (UDP or TCP) used to open a channel between clients and
25415 Defaults to @samp{udp}.
25419 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
25420 The device type used to represent the VPN connection.
25422 Defaults to @samp{tun}.
25426 If you do not have some of these files (eg.@: you use a username and
25427 password), you can disable any of the following three fields by setting
25428 it to @code{'disabled}.
25430 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string ca
25431 The certificate authority to check connections against.
25433 Defaults to @samp{"/etc/openvpn/ca.crt"}.
25437 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string cert
25438 The certificate of the machine the daemon is running on. It should be
25439 signed by the authority given in @code{ca}.
25441 Defaults to @samp{"/etc/openvpn/client.crt"}.
25445 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string key
25446 The key of the machine the daemon is running on. It must be the key whose
25447 certificate is @code{cert}.
25449 Defaults to @samp{"/etc/openvpn/client.key"}.
25453 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
25454 Whether to use the lzo compression algorithm.
25456 Defaults to @samp{#t}.
25460 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
25461 Don't re-read key files across SIGUSR1 or --ping-restart.
25463 Defaults to @samp{#t}.
25467 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
25468 Don't close and reopen TUN/TAP device or run up/down scripts across
25469 SIGUSR1 or --ping-restart restarts.
25471 Defaults to @samp{#t}.
25475 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
25476 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
25477 poll/epoll/select prior to the write operation.
25479 Defaults to @samp{#f}.
25482 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
25485 Defaults to @samp{3}.
25489 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
25490 Add an additional layer of HMAC authentication on top of the TLS control
25491 channel to protect against DoS attacks.
25493 Defaults to @samp{#f}.
25497 @deftypevr {@code{openvpn-server-configuration} parameter} number port
25498 Specifies the port number on which the server listens.
25500 Defaults to @samp{1194}.
25504 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
25505 An ip and mask specifying the subnet inside the virtual network.
25507 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
25511 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
25512 A CIDR notation specifying the IPv6 subnet inside the virtual network.
25514 Defaults to @samp{#f}.
25518 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
25519 The Diffie-Hellman parameters file.
25521 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
25525 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
25526 The file that records client IPs.
25528 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
25532 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
25533 When true, the server will act as a gateway for its clients.
25535 Defaults to @samp{#f}.
25539 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
25540 When true, clients are allowed to talk to each other inside the VPN.
25542 Defaults to @samp{#f}.
25546 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
25547 Causes ping-like messages to be sent back and forth over the link so
25548 that each side knows when the other side has gone down. @code{keepalive}
25549 requires a pair. The first element is the period of the ping sending,
25550 and the second element is the timeout before considering the other side
25555 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
25556 The maximum number of clients.
25558 Defaults to @samp{100}.
25562 @deftypevr {@code{openvpn-server-configuration} parameter} string status
25563 The status file. This file shows a small report on current connection.
25564 It is truncated and rewritten every minute.
25566 Defaults to @samp{"/var/run/openvpn/status"}.
25570 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
25571 The list of configuration for some clients.
25573 Defaults to @samp{()}.
25575 Available @code{openvpn-ccd-configuration} fields are:
25577 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
25580 Defaults to @samp{"client"}.
25584 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
25587 Defaults to @samp{#f}.
25591 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
25594 Defaults to @samp{#f}.
25601 @c %end of automatic openvpn-server documentation
25604 @node Network File System
25605 @subsection Network File System
25608 The @code{(gnu services nfs)} module provides the following services,
25609 which are most commonly used in relation to mounting or exporting
25610 directory trees as @dfn{network file systems} (NFS).
25612 While it is possible to use the individual components that together make
25613 up a Network File System service, we recommended to configure an NFS
25614 server with the @code{nfs-service-type}.
25616 @subsubheading NFS Service
25617 @cindex NFS, server
25619 The NFS service takes care of setting up all NFS component services,
25620 kernel configuration file systems, and installs configuration files in
25621 the locations that NFS expects.
25623 @defvr {Scheme Variable} nfs-service-type
25624 A service type for a complete NFS server.
25627 @deftp {Data Type} nfs-configuration
25628 This data type represents the configuration of the NFS service and all
25631 It has the following parameters:
25633 @item @code{nfs-utils} (default: @code{nfs-utils})
25634 The nfs-utils package to use.
25636 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
25637 If a list of string values is provided, the @command{rpc.nfsd} daemon
25638 will be limited to supporting the given versions of the NFS protocol.
25640 @item @code{exports} (default: @code{'()})
25641 This is a list of directories the NFS server should export. Each entry
25642 is a list consisting of two elements: a directory name and a string
25643 containing all options. This is an example in which the directory
25644 @file{/export} is served to all NFS clients as a read-only share:
25650 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
25653 @item @code{rpcmountd-port} (default: @code{#f})
25654 The network port that the @command{rpc.mountd} daemon should use.
25656 @item @code{rpcstatd-port} (default: @code{#f})
25657 The network port that the @command{rpc.statd} daemon should use.
25659 @item @code{rpcbind} (default: @code{rpcbind})
25660 The rpcbind package to use.
25662 @item @code{idmap-domain} (default: @code{"localdomain"})
25663 The local NFSv4 domain name.
25665 @item @code{nfsd-port} (default: @code{2049})
25666 The network port that the @command{nfsd} daemon should use.
25668 @item @code{nfsd-threads} (default: @code{8})
25669 The number of threads used by the @command{nfsd} daemon.
25671 @item @code{nfsd-tcp?} (default: @code{#t})
25672 Whether the @command{nfsd} daemon should listen on a TCP socket.
25674 @item @code{nfsd-udp?} (default: @code{#f})
25675 Whether the @command{nfsd} daemon should listen on a UDP socket.
25677 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
25678 The directory where the pipefs file system is mounted.
25680 @item @code{debug} (default: @code{'()"})
25681 A list of subsystems for which debugging output should be enabled. This
25682 is a list of symbols. Any of these symbols are valid: @code{nfsd},
25683 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
25687 If you don't need a complete NFS service or prefer to build it yourself
25688 you can use the individual component services that are documented below.
25690 @subsubheading RPC Bind Service
25693 The RPC Bind service provides a facility to map program numbers into
25694 universal addresses.
25695 Many NFS related services use this facility. Hence it is automatically
25696 started when a dependent service starts.
25698 @defvr {Scheme Variable} rpcbind-service-type
25699 A service type for the RPC portmapper daemon.
25703 @deftp {Data Type} rpcbind-configuration
25704 Data type representing the configuration of the RPC Bind Service.
25705 This type has the following parameters:
25707 @item @code{rpcbind} (default: @code{rpcbind})
25708 The rpcbind package to use.
25710 @item @code{warm-start?} (default: @code{#t})
25711 If this parameter is @code{#t}, then the daemon will read a
25712 state file on startup thus reloading state information saved by a previous
25718 @subsubheading Pipefs Pseudo File System
25722 The pipefs file system is used to transfer NFS related data
25723 between the kernel and user space programs.
25725 @defvr {Scheme Variable} pipefs-service-type
25726 A service type for the pipefs pseudo file system.
25729 @deftp {Data Type} pipefs-configuration
25730 Data type representing the configuration of the pipefs pseudo file system service.
25731 This type has the following parameters:
25733 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
25734 The directory to which the file system is to be attached.
25739 @subsubheading GSS Daemon Service
25742 @cindex global security system
25744 The @dfn{global security system} (GSS) daemon provides strong security for RPC
25746 Before exchanging RPC requests an RPC client must establish a security
25747 context. Typically this is done using the Kerberos command @command{kinit}
25748 or automatically at login time using PAM services (@pxref{Kerberos Services}).
25750 @defvr {Scheme Variable} gss-service-type
25751 A service type for the Global Security System (GSS) daemon.
25754 @deftp {Data Type} gss-configuration
25755 Data type representing the configuration of the GSS daemon service.
25756 This type has the following parameters:
25758 @item @code{nfs-utils} (default: @code{nfs-utils})
25759 The package in which the @command{rpc.gssd} command is to be found.
25761 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
25762 The directory where the pipefs file system is mounted.
25768 @subsubheading IDMAP Daemon Service
25770 @cindex name mapper
25772 The idmap daemon service provides mapping between user IDs and user names.
25773 Typically it is required in order to access file systems mounted via NFSv4.
25775 @defvr {Scheme Variable} idmap-service-type
25776 A service type for the Identity Mapper (IDMAP) daemon.
25779 @deftp {Data Type} idmap-configuration
25780 Data type representing the configuration of the IDMAP daemon service.
25781 This type has the following parameters:
25783 @item @code{nfs-utils} (default: @code{nfs-utils})
25784 The package in which the @command{rpc.idmapd} command is to be found.
25786 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
25787 The directory where the pipefs file system is mounted.
25789 @item @code{domain} (default: @code{#f})
25790 The local NFSv4 domain name.
25791 This must be a string or @code{#f}.
25792 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
25794 @item @code{verbosity} (default: @code{0})
25795 The verbosity level of the daemon.
25800 @node Continuous Integration
25801 @subsection Continuous Integration
25803 @cindex continuous integration
25804 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
25805 continuous integration tool for Guix. It can be used both for development and
25806 for providing substitutes to others (@pxref{Substitutes}).
25808 The @code{(gnu services cuirass)} module provides the following service.
25810 @defvr {Scheme Procedure} cuirass-service-type
25811 The type of the Cuirass service. Its value must be a
25812 @code{cuirass-configuration} object, as described below.
25815 To add build jobs, you have to set the @code{specifications} field of the
25816 configuration. Here is an example of a service that polls the Guix repository
25817 and builds the packages from a manifest. Some of the packages are defined in
25818 the @code{"custom-packages"} input, which is the equivalent of
25819 @env{GUIX_PACKAGE_PATH}.
25822 (define %cuirass-specs
25824 '((#:name . "my-manifest")
25825 (#:load-path-inputs . ("guix"))
25826 (#:package-path-inputs . ("custom-packages"))
25827 (#:proc-input . "guix")
25828 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
25829 (#:proc . cuirass-jobs)
25830 (#:proc-args . ((subset . "manifests")
25831 (systems . ("x86_64-linux"))
25832 (manifests . (("config" . "guix/manifest.scm")))))
25833 (#:inputs . (((#:name . "guix")
25834 (#:url . "git://git.savannah.gnu.org/guix.git")
25835 (#:load-path . ".")
25836 (#:branch . "master")
25837 (#:no-compile? . #t))
25838 ((#:name . "config")
25839 (#:url . "https://git.example.org/config.git")
25840 (#:load-path . ".")
25841 (#:branch . "master")
25842 (#:no-compile? . #t))
25843 ((#:name . "custom-packages")
25844 (#:url . "https://git.example.org/custom-packages.git")
25845 (#:load-path . ".")
25846 (#:branch . "master")
25847 (#:no-compile? . #t)))))))
25849 (service cuirass-service-type
25850 (cuirass-configuration
25851 (specifications %cuirass-specs)))
25854 While information related to build jobs is located directly in the
25855 specifications, global settings for the @command{cuirass} process are
25856 accessible in other @code{cuirass-configuration} fields.
25858 @deftp {Data Type} cuirass-configuration
25859 Data type representing the configuration of Cuirass.
25862 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
25863 Location of the log file.
25865 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
25866 Location of the log file used by the web interface.
25868 @item @code{queries-log-file} (default: @code{#f})
25869 Location of the SQL queries log file. By default, SQL queries logging is
25872 @item @code{web-queries-log-file} (default: @code{#f})
25873 Location of the web SQL queries log file. By default, web SQL queries
25874 logging is disabled.
25876 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
25877 Location of the repository cache.
25879 @item @code{user} (default: @code{"cuirass"})
25880 Owner of the @code{cuirass} process.
25882 @item @code{group} (default: @code{"cuirass"})
25883 Owner's group of the @code{cuirass} process.
25885 @item @code{interval} (default: @code{60})
25886 Number of seconds between the poll of the repositories followed by the
25889 @item @code{queue-size} (default: @code{1})
25890 Size of the database writer queue.
25892 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
25893 Location of sqlite database which contains the build results and previously
25894 added specifications.
25896 @item @code{ttl} (default: @code{(* 30 24 3600)})
25897 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
25898 are registered for build results. This means that build results are protected
25899 from garbage collection for at least @var{ttl} seconds.
25901 @item @code{port} (default: @code{8081})
25902 Port number used by the HTTP server.
25904 @item @code{host} (default: @code{"localhost"})
25905 Listen on the network interface for @var{host}. The default is to
25906 accept connections from localhost.
25908 @item @code{specifications} (default: @code{#~'()})
25909 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
25910 where a specification is an association list
25911 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
25912 keys are keywords (@code{#:keyword-example}) as shown in the example
25915 @item @code{use-substitutes?} (default: @code{#f})
25916 This allows using substitutes to avoid building every dependencies of a job
25919 @item @code{one-shot?} (default: @code{#f})
25920 Only evaluate specifications and build derivations once.
25922 @item @code{fallback?} (default: @code{#f})
25923 When substituting a pre-built binary fails, fall back to building
25926 @item @code{extra-options} (default: @code{'()})
25927 Extra options to pass when running the Cuirass processes.
25929 @item @code{cuirass} (default: @code{cuirass})
25930 The Cuirass package to use.
25934 @node Power Management Services
25935 @subsection Power Management Services
25938 @cindex power management with TLP
25939 @subsubheading TLP daemon
25941 The @code{(gnu services pm)} module provides a Guix service definition
25942 for the Linux power management tool TLP.
25944 TLP enables various powersaving modes in userspace and kernel.
25945 Contrary to @code{upower-service}, it is not a passive,
25946 monitoring tool, as it will apply custom settings each time a new power
25947 source is detected. More information can be found at
25948 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
25950 @deffn {Scheme Variable} tlp-service-type
25951 The service type for the TLP tool. The default settings are optimised
25952 for battery life on most systems, but you can tweak them to your heart's
25953 content by adding a valid @code{tlp-configuration}:
25955 (service tlp-service-type
25957 (cpu-scaling-governor-on-ac (list "performance"))
25958 (sched-powersave-on-bat? #t)))
25962 Each parameter definition is preceded by its type; for example,
25963 @samp{boolean foo} indicates that the @code{foo} parameter
25964 should be specified as a boolean. Types starting with
25965 @code{maybe-} denote parameters that won't show up in TLP config file
25966 when their value is @code{'disabled}.
25968 @c The following documentation was initially generated by
25969 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
25970 @c documentation is better, so we shouldn't hesitate to edit below as
25971 @c needed. However if the change you want to make to this documentation
25972 @c can be done in an automated way, it's probably easier to change
25973 @c (generate-documentation) than to make it below and have to deal with
25974 @c the churn as TLP updates.
25976 Available @code{tlp-configuration} fields are:
25978 @deftypevr {@code{tlp-configuration} parameter} package tlp
25983 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
25984 Set to true if you wish to enable TLP.
25986 Defaults to @samp{#t}.
25990 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
25991 Default mode when no power supply can be detected. Alternatives are AC
25994 Defaults to @samp{"AC"}.
25998 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
25999 Number of seconds Linux kernel has to wait after the disk goes idle,
26000 before syncing on AC.
26002 Defaults to @samp{0}.
26006 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
26007 Same as @code{disk-idle-ac} but on BAT mode.
26009 Defaults to @samp{2}.
26013 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
26014 Dirty pages flushing periodicity, expressed in seconds.
26016 Defaults to @samp{15}.
26020 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
26021 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
26023 Defaults to @samp{60}.
26027 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
26028 CPU frequency scaling governor on AC mode. With intel_pstate driver,
26029 alternatives are powersave and performance. With acpi-cpufreq driver,
26030 alternatives are ondemand, powersave, performance and conservative.
26032 Defaults to @samp{disabled}.
26036 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
26037 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
26039 Defaults to @samp{disabled}.
26043 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
26044 Set the min available frequency for the scaling governor on AC.
26046 Defaults to @samp{disabled}.
26050 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
26051 Set the max available frequency for the scaling governor on AC.
26053 Defaults to @samp{disabled}.
26057 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
26058 Set the min available frequency for the scaling governor on BAT.
26060 Defaults to @samp{disabled}.
26064 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
26065 Set the max available frequency for the scaling governor on BAT.
26067 Defaults to @samp{disabled}.
26071 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
26072 Limit the min P-state to control the power dissipation of the CPU, in AC
26073 mode. Values are stated as a percentage of the available performance.
26075 Defaults to @samp{disabled}.
26079 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
26080 Limit the max P-state to control the power dissipation of the CPU, in AC
26081 mode. Values are stated as a percentage of the available performance.
26083 Defaults to @samp{disabled}.
26087 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
26088 Same as @code{cpu-min-perf-on-ac} on BAT mode.
26090 Defaults to @samp{disabled}.
26094 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
26095 Same as @code{cpu-max-perf-on-ac} on BAT mode.
26097 Defaults to @samp{disabled}.
26101 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
26102 Enable CPU turbo boost feature on AC mode.
26104 Defaults to @samp{disabled}.
26108 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
26109 Same as @code{cpu-boost-on-ac?} on BAT mode.
26111 Defaults to @samp{disabled}.
26115 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
26116 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
26117 used under light load conditions.
26119 Defaults to @samp{#f}.
26123 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
26124 Same as @code{sched-powersave-on-ac?} but on BAT mode.
26126 Defaults to @samp{#t}.
26130 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
26131 Enable Linux kernel NMI watchdog.
26133 Defaults to @samp{#f}.
26137 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
26138 For Linux kernels with PHC patch applied, change CPU voltages. An
26139 example value would be @samp{"F:V F:V F:V F:V"}.
26141 Defaults to @samp{disabled}.
26145 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
26146 Set CPU performance versus energy saving policy on AC. Alternatives are
26147 performance, normal, powersave.
26149 Defaults to @samp{"performance"}.
26153 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
26154 Same as @code{energy-perf-policy-ac} but on BAT mode.
26156 Defaults to @samp{"powersave"}.
26160 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
26165 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
26166 Hard disk advanced power management level.
26170 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
26171 Same as @code{disk-apm-bat} but on BAT mode.
26175 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
26176 Hard disk spin down timeout. One value has to be specified for each
26177 declared hard disk.
26179 Defaults to @samp{disabled}.
26183 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
26184 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
26186 Defaults to @samp{disabled}.
26190 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
26191 Select IO scheduler for disk devices. One value has to be specified for
26192 each declared hard disk. Example alternatives are cfq, deadline and
26195 Defaults to @samp{disabled}.
26199 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
26200 SATA aggressive link power management (ALPM) level. Alternatives are
26201 min_power, medium_power, max_performance.
26203 Defaults to @samp{"max_performance"}.
26207 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
26208 Same as @code{sata-linkpwr-ac} but on BAT mode.
26210 Defaults to @samp{"min_power"}.
26214 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
26215 Exclude specified SATA host devices for link power management.
26217 Defaults to @samp{disabled}.
26221 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
26222 Enable Runtime Power Management for AHCI controller and disks on AC
26225 Defaults to @samp{disabled}.
26229 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
26230 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
26232 Defaults to @samp{disabled}.
26236 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
26237 Seconds of inactivity before disk is suspended.
26239 Defaults to @samp{15}.
26243 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
26244 PCI Express Active State Power Management level. Alternatives are
26245 default, performance, powersave.
26247 Defaults to @samp{"performance"}.
26251 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
26252 Same as @code{pcie-aspm-ac} but on BAT mode.
26254 Defaults to @samp{"powersave"}.
26258 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
26259 Radeon graphics clock speed level. Alternatives are low, mid, high,
26262 Defaults to @samp{"high"}.
26266 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
26267 Same as @code{radeon-power-ac} but on BAT mode.
26269 Defaults to @samp{"low"}.
26273 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
26274 Radeon dynamic power management method (DPM). Alternatives are battery,
26277 Defaults to @samp{"performance"}.
26281 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
26282 Same as @code{radeon-dpm-state-ac} but on BAT mode.
26284 Defaults to @samp{"battery"}.
26288 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
26289 Radeon DPM performance level. Alternatives are auto, low, high.
26291 Defaults to @samp{"auto"}.
26295 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
26296 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
26298 Defaults to @samp{"auto"}.
26302 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
26303 Wifi power saving mode.
26305 Defaults to @samp{#f}.
26309 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
26310 Same as @code{wifi-power-ac?} but on BAT mode.
26312 Defaults to @samp{#t}.
26316 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
26317 Disable wake on LAN.
26319 Defaults to @samp{#t}.
26323 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
26324 Timeout duration in seconds before activating audio power saving on
26325 Intel HDA and AC97 devices. A value of 0 disables power saving.
26327 Defaults to @samp{0}.
26331 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
26332 Same as @code{sound-powersave-ac} but on BAT mode.
26334 Defaults to @samp{1}.
26338 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
26339 Disable controller in powersaving mode on Intel HDA devices.
26341 Defaults to @samp{#t}.
26345 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
26346 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
26347 powered on again by releasing (and reinserting) the eject lever or by
26348 pressing the disc eject button on newer models.
26350 Defaults to @samp{#f}.
26354 @deftypevr {@code{tlp-configuration} parameter} string bay-device
26355 Name of the optical drive device to power off.
26357 Defaults to @samp{"sr0"}.
26361 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
26362 Runtime Power Management for PCI(e) bus devices. Alternatives are on
26365 Defaults to @samp{"on"}.
26369 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
26370 Same as @code{runtime-pm-ac} but on BAT mode.
26372 Defaults to @samp{"auto"}.
26376 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
26377 Runtime Power Management for all PCI(e) bus devices, except blacklisted
26380 Defaults to @samp{#t}.
26384 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
26385 Exclude specified PCI(e) device addresses from Runtime Power Management.
26387 Defaults to @samp{disabled}.
26391 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
26392 Exclude PCI(e) devices assigned to the specified drivers from Runtime
26397 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
26398 Enable USB autosuspend feature.
26400 Defaults to @samp{#t}.
26404 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
26405 Exclude specified devices from USB autosuspend.
26407 Defaults to @samp{disabled}.
26411 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
26412 Exclude WWAN devices from USB autosuspend.
26414 Defaults to @samp{#t}.
26418 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
26419 Include specified devices into USB autosuspend, even if they are already
26420 excluded by the driver or via @code{usb-blacklist-wwan?}.
26422 Defaults to @samp{disabled}.
26426 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
26427 Enable USB autosuspend before shutdown.
26429 Defaults to @samp{disabled}.
26433 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
26434 Restore radio device state (bluetooth, wifi, wwan) from previous
26435 shutdown on system startup.
26437 Defaults to @samp{#f}.
26442 @cindex CPU frequency scaling with thermald
26443 @subsubheading Thermald daemon
26445 The @code{(gnu services pm)} module provides an interface to
26446 thermald, a CPU frequency scaling service which helps prevent overheating.
26448 @defvr {Scheme Variable} thermald-service-type
26449 This is the service type for
26450 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
26451 Thermal Daemon, which is responsible for controlling the thermal state
26452 of processors and preventing overheating.
26455 @deftp {Data Type} thermald-configuration
26456 Data type representing the configuration of @code{thermald-service-type}.
26459 @item @code{ignore-cpuid-check?} (default: @code{#f})
26460 Ignore cpuid check for supported CPU models.
26462 @item @code{thermald} (default: @var{thermald})
26463 Package object of thermald.
26468 @node Audio Services
26469 @subsection Audio Services
26471 The @code{(gnu services audio)} module provides a service to start MPD
26472 (the Music Player Daemon).
26475 @subsubheading Music Player Daemon
26477 The Music Player Daemon (MPD) is a service that can play music while
26478 being controlled from the local machine or over the network by a variety
26481 The following example shows how one might run @code{mpd} as user
26482 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
26485 (service mpd-service-type
26491 @defvr {Scheme Variable} mpd-service-type
26492 The service type for @command{mpd}
26495 @deftp {Data Type} mpd-configuration
26496 Data type representing the configuration of @command{mpd}.
26499 @item @code{user} (default: @code{"mpd"})
26500 The user to run mpd as.
26502 @item @code{music-dir} (default: @code{"~/Music"})
26503 The directory to scan for music files.
26505 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
26506 The directory to store playlists.
26508 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
26509 The location of the music database.
26511 @item @code{state-file} (default: @code{"~/.mpd/state"})
26512 The location of the file that stores current MPD's state.
26514 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
26515 The location of the sticker database.
26517 @item @code{port} (default: @code{"6600"})
26518 The port to run mpd on.
26520 @item @code{address} (default: @code{"any"})
26521 The address that mpd will bind to. To use a Unix domain socket,
26522 an absolute path can be specified here.
26524 @item @code{outputs} (default: @code{"(list (mpd-output))"})
26525 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
26530 @deftp {Data Type} mpd-output
26531 Data type representing an @command{mpd} audio output.
26534 @item @code{name} (default: @code{"MPD"})
26535 The name of the audio output.
26537 @item @code{type} (default: @code{"pulse"})
26538 The type of audio output.
26540 @item @code{enabled?} (default: @code{#t})
26541 Specifies whether this audio output is enabled when MPD is started. By
26542 default, all audio outputs are enabled. This is just the default
26543 setting when there is no state file; with a state file, the previous
26546 @item @code{tags?} (default: @code{#t})
26547 If set to @code{#f}, then MPD will not send tags to this output. This
26548 is only useful for output plugins that can receive tags, for example the
26549 @code{httpd} output plugin.
26551 @item @code{always-on?} (default: @code{#f})
26552 If set to @code{#t}, then MPD attempts to keep this audio output always
26553 open. This may be useful for streaming servers, when you don’t want to
26554 disconnect all listeners even when playback is accidentally stopped.
26556 @item @code{mixer-type}
26557 This field accepts a symbol that specifies which mixer should be used
26558 for this audio output: the @code{hardware} mixer, the @code{software}
26559 mixer, the @code{null} mixer (allows setting the volume, but with no
26560 effect; this can be used as a trick to implement an external mixer
26561 External Mixer) or no mixer (@code{none}).
26563 @item @code{extra-options} (default: @code{'()})
26564 An association list of option symbols to string values to be appended to
26565 the audio output configuration.
26570 The following example shows a configuration of @code{mpd} that provides
26571 an HTTP audio streaming output.
26574 (service mpd-service-type
26582 `((encoder . "vorbis")
26583 (port . "8080"))))))))
26587 @node Virtualization Services
26588 @subsection Virtualization Services
26590 The @code{(gnu services virtualization)} module provides services for
26591 the libvirt and virtlog daemons, as well as other virtualization-related
26594 @subsubheading Libvirt daemon
26596 @code{libvirtd} is the server side daemon component of the libvirt
26597 virtualization management system. This daemon runs on host servers
26598 and performs required management tasks for virtualized guests.
26600 @deffn {Scheme Variable} libvirt-service-type
26601 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
26602 Its value must be a @code{libvirt-configuration}.
26605 (service libvirt-service-type
26606 (libvirt-configuration
26607 (unix-sock-group "libvirt")
26608 (tls-port "16555")))
26612 @c Auto-generated with (generate-libvirt-documentation)
26613 Available @code{libvirt-configuration} fields are:
26615 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
26620 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
26621 Flag listening for secure TLS connections on the public TCP/IP port.
26622 You must set @code{listen} for this to have any effect.
26624 It is necessary to setup a CA and issue server certificates before using
26627 Defaults to @samp{#t}.
26631 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
26632 Listen for unencrypted TCP connections on the public TCP/IP port. You must
26633 set @code{listen} for this to have any effect.
26635 Using the TCP socket requires SASL authentication by default. Only SASL
26636 mechanisms which support data encryption are allowed. This is
26637 DIGEST_MD5 and GSSAPI (Kerberos5).
26639 Defaults to @samp{#f}.
26643 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
26644 Port for accepting secure TLS connections. This can be a port number,
26647 Defaults to @samp{"16514"}.
26651 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
26652 Port for accepting insecure TCP connections. This can be a port number,
26655 Defaults to @samp{"16509"}.
26659 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
26660 IP address or hostname used for client connections.
26662 Defaults to @samp{"0.0.0.0"}.
26666 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
26667 Flag toggling mDNS advertisement of the libvirt service.
26669 Alternatively can disable for all services on a host by stopping the
26672 Defaults to @samp{#f}.
26676 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
26677 Default mDNS advertisement name. This must be unique on the immediate
26680 Defaults to @samp{"Virtualization Host <hostname>"}.
26684 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
26685 UNIX domain socket group ownership. This can be used to allow a
26686 'trusted' set of users access to management capabilities without
26689 Defaults to @samp{"root"}.
26693 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
26694 UNIX socket permissions for the R/O socket. This is used for monitoring
26697 Defaults to @samp{"0777"}.
26701 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
26702 UNIX socket permissions for the R/W socket. Default allows only root.
26703 If PolicyKit is enabled on the socket, the default will change to allow
26704 everyone (eg, 0777)
26706 Defaults to @samp{"0770"}.
26710 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
26711 UNIX socket permissions for the admin socket. Default allows only owner
26712 (root), do not change it unless you are sure to whom you are exposing
26715 Defaults to @samp{"0777"}.
26719 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
26720 The directory in which sockets will be found/created.
26722 Defaults to @samp{"/var/run/libvirt"}.
26726 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
26727 Authentication scheme for UNIX read-only sockets. By default socket
26728 permissions allow anyone to connect
26730 Defaults to @samp{"polkit"}.
26734 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
26735 Authentication scheme for UNIX read-write sockets. By default socket
26736 permissions only allow root. If PolicyKit support was compiled into
26737 libvirt, the default will be to use 'polkit' auth.
26739 Defaults to @samp{"polkit"}.
26743 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
26744 Authentication scheme for TCP sockets. If you don't enable SASL, then
26745 all TCP traffic is cleartext. Don't do this outside of a dev/test
26748 Defaults to @samp{"sasl"}.
26752 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
26753 Authentication scheme for TLS sockets. TLS sockets already have
26754 encryption provided by the TLS layer, and limited authentication is done
26757 It is possible to make use of any SASL authentication mechanism as well,
26758 by using 'sasl' for this option
26760 Defaults to @samp{"none"}.
26764 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
26765 API access control scheme.
26767 By default an authenticated user is allowed access to all APIs. Access
26768 drivers can place restrictions on this.
26770 Defaults to @samp{()}.
26774 @deftypevr {@code{libvirt-configuration} parameter} string key-file
26775 Server key file path. If set to an empty string, then no private key is
26778 Defaults to @samp{""}.
26782 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
26783 Server key file path. If set to an empty string, then no certificate is
26786 Defaults to @samp{""}.
26790 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
26791 Server key file path. If set to an empty string, then no CA certificate
26794 Defaults to @samp{""}.
26798 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
26799 Certificate revocation list path. If set to an empty string, then no
26802 Defaults to @samp{""}.
26806 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
26807 Disable verification of our own server certificates.
26809 When libvirtd starts it performs some sanity checks against its own
26812 Defaults to @samp{#f}.
26816 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
26817 Disable verification of client certificates.
26819 Client certificate verification is the primary authentication mechanism.
26820 Any client which does not present a certificate signed by the CA will be
26823 Defaults to @samp{#f}.
26827 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
26828 Whitelist of allowed x509 Distinguished Name.
26830 Defaults to @samp{()}.
26834 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
26835 Whitelist of allowed SASL usernames. The format for username depends on
26836 the SASL authentication mechanism.
26838 Defaults to @samp{()}.
26842 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
26843 Override the compile time default TLS priority string. The default is
26844 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
26845 is desired for libvirt to deviate from the global default settings.
26847 Defaults to @samp{"NORMAL"}.
26851 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
26852 Maximum number of concurrent client connections to allow over all
26855 Defaults to @samp{5000}.
26859 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
26860 Maximum length of queue of connections waiting to be accepted by the
26861 daemon. Note, that some protocols supporting retransmission may obey
26862 this so that a later reattempt at connection succeeds.
26864 Defaults to @samp{1000}.
26868 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
26869 Maximum length of queue of accepted but not yet authenticated clients.
26870 Set this to zero to turn this feature off
26872 Defaults to @samp{20}.
26876 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
26877 Number of workers to start up initially.
26879 Defaults to @samp{5}.
26883 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
26884 Maximum number of worker threads.
26886 If the number of active clients exceeds @code{min-workers}, then more
26887 threads are spawned, up to max_workers limit. Typically you'd want
26888 max_workers to equal maximum number of clients allowed.
26890 Defaults to @samp{20}.
26894 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
26895 Number of priority workers. If all workers from above pool are stuck,
26896 some calls marked as high priority (notably domainDestroy) can be
26897 executed in this pool.
26899 Defaults to @samp{5}.
26903 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
26904 Total global limit on concurrent RPC calls.
26906 Defaults to @samp{20}.
26910 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
26911 Limit on concurrent requests from a single client connection. To avoid
26912 one client monopolizing the server this should be a small fraction of
26913 the global max_requests and max_workers parameter.
26915 Defaults to @samp{5}.
26919 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
26920 Same as @code{min-workers} but for the admin interface.
26922 Defaults to @samp{1}.
26926 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
26927 Same as @code{max-workers} but for the admin interface.
26929 Defaults to @samp{5}.
26933 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
26934 Same as @code{max-clients} but for the admin interface.
26936 Defaults to @samp{5}.
26940 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
26941 Same as @code{max-queued-clients} but for the admin interface.
26943 Defaults to @samp{5}.
26947 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
26948 Same as @code{max-client-requests} but for the admin interface.
26950 Defaults to @samp{5}.
26954 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
26955 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
26957 Defaults to @samp{3}.
26961 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
26964 A filter allows to select a different logging level for a given category
26965 of logs. The format for a filter is one of:
26976 where @code{name} is a string which is matched against the category
26977 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
26978 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
26979 name in the filter can be a substring of the full category name, in
26980 order to match multiple similar categories), the optional @samp{"+"}
26981 prefix tells libvirt to log stack trace for each message matching name,
26982 and @code{x} is the minimal level where matching messages should be
27000 Multiple filters can be defined in a single filters statement, they just
27001 need to be separated by spaces.
27003 Defaults to @samp{"3:remote 4:event"}.
27007 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
27010 An output is one of the places to save logging information. The format
27011 for an output can be:
27015 output goes to stderr
27017 @item x:syslog:name
27018 use syslog for the output and use the given name as the ident
27020 @item x:file:file_path
27021 output to a file, with the given filepath
27024 output to journald logging system
27028 In all case the x prefix is the minimal level, acting as a filter
27045 Multiple outputs can be defined, they just need to be separated by
27048 Defaults to @samp{"3:stderr"}.
27052 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
27053 Allows usage of the auditing subsystem to be altered
27057 0: disable all auditing
27060 1: enable auditing, only if enabled on host
27063 2: enable auditing, and exit if disabled on host.
27067 Defaults to @samp{1}.
27071 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
27072 Send audit messages via libvirt logging infrastructure.
27074 Defaults to @samp{#f}.
27078 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
27079 Host UUID. UUID must not have all digits be the same.
27081 Defaults to @samp{""}.
27085 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
27086 Source to read host UUID.
27090 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
27093 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
27097 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
27100 Defaults to @samp{"smbios"}.
27104 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
27105 A keepalive message is sent to a client after @code{keepalive_interval}
27106 seconds of inactivity to check if the client is still responding. If
27107 set to -1, libvirtd will never send keepalive requests; however clients
27108 can still send them and the daemon will send responses.
27110 Defaults to @samp{5}.
27114 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
27115 Maximum number of keepalive messages that are allowed to be sent to the
27116 client without getting any response before the connection is considered
27119 In other words, the connection is automatically closed approximately
27120 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
27121 the last message received from the client. When @code{keepalive-count}
27122 is set to 0, connections will be automatically closed after
27123 @code{keepalive-interval} seconds of inactivity without sending any
27124 keepalive messages.
27126 Defaults to @samp{5}.
27130 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
27131 Same as above but for admin interface.
27133 Defaults to @samp{5}.
27137 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
27138 Same as above but for admin interface.
27140 Defaults to @samp{5}.
27144 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
27145 Timeout for Open vSwitch calls.
27147 The @code{ovs-vsctl} utility is used for the configuration and its
27148 timeout option is set by default to 5 seconds to avoid potential
27149 infinite waits blocking libvirt.
27151 Defaults to @samp{5}.
27155 @c %end of autogenerated docs
27157 @subsubheading Virtlog daemon
27158 The virtlogd service is a server side daemon component of libvirt that is
27159 used to manage logs from virtual machine consoles.
27161 This daemon is not used directly by libvirt client applications, rather it
27162 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
27163 standalone daemon, the main @code{libvirtd} daemon can be restarted without
27164 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
27165 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
27167 @deffn {Scheme Variable} virtlog-service-type
27168 This is the type of the virtlog daemon.
27169 Its value must be a @code{virtlog-configuration}.
27172 (service virtlog-service-type
27173 (virtlog-configuration
27174 (max-clients 1000)))
27178 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
27179 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
27181 Defaults to @samp{3}.
27185 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
27188 A filter allows to select a different logging level for a given category
27189 of logs The format for a filter is one of:
27200 where @code{name} is a string which is matched against the category
27201 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
27202 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
27203 be a substring of the full category name, in order to match multiple
27204 similar categories), the optional "+" prefix tells libvirt to log stack
27205 trace for each message matching name, and @code{x} is the minimal level
27206 where matching messages should be logged:
27223 Multiple filters can be defined in a single filters statement, they just
27224 need to be separated by spaces.
27226 Defaults to @samp{"3:remote 4:event"}.
27230 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
27233 An output is one of the places to save logging information The format
27234 for an output can be:
27238 output goes to stderr
27240 @item x:syslog:name
27241 use syslog for the output and use the given name as the ident
27243 @item x:file:file_path
27244 output to a file, with the given filepath
27247 output to journald logging system
27251 In all case the x prefix is the minimal level, acting as a filter
27268 Multiple outputs can be defined, they just need to be separated by
27271 Defaults to @samp{"3:stderr"}.
27275 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
27276 Maximum number of concurrent client connections to allow over all
27279 Defaults to @samp{1024}.
27283 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
27284 Maximum file size before rolling over.
27286 Defaults to @samp{2MB}
27290 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
27291 Maximum number of backup files to keep.
27293 Defaults to @samp{3}
27297 @anchor{transparent-emulation-qemu}
27298 @subsubheading Transparent Emulation with QEMU
27301 @cindex @code{binfmt_misc}
27302 @code{qemu-binfmt-service-type} provides support for transparent
27303 emulation of program binaries built for different architectures---e.g.,
27304 it allows you to transparently execute an ARMv7 program on an x86_64
27305 machine. It achieves this by combining the @uref{https://www.qemu.org,
27306 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
27307 This feature only allows you to emulate GNU/Linux on a different
27308 architecture, but see below for GNU/Hurd support.
27310 @defvr {Scheme Variable} qemu-binfmt-service-type
27311 This is the type of the QEMU/binfmt service for transparent emulation.
27312 Its value must be a @code{qemu-binfmt-configuration} object, which
27313 specifies the QEMU package to use as well as the architecture we want to
27317 (service qemu-binfmt-service-type
27318 (qemu-binfmt-configuration
27319 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
27322 In this example, we enable transparent emulation for the ARM and aarch64
27323 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
27324 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
27325 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
27328 @deftp {Data Type} qemu-binfmt-configuration
27329 This is the configuration for the @code{qemu-binfmt} service.
27332 @item @code{platforms} (default: @code{'()})
27333 The list of emulated QEMU platforms. Each item must be a @dfn{platform
27334 object} as returned by @code{lookup-qemu-platforms} (see below).
27336 @item @code{guix-support?} (default: @code{#f})
27337 When it is true, QEMU and all its dependencies are added to the build
27338 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
27339 @option{--chroot-directory} option}). This allows the @code{binfmt_misc}
27340 handlers to be used within the build environment, which in turn means
27341 that you can transparently build programs for another architecture.
27343 For example, let's suppose you're on an x86_64 machine and you have this
27347 (service qemu-binfmt-service-type
27348 (qemu-binfmt-configuration
27349 (platforms (lookup-qemu-platforms "arm"))
27350 (guix-support? #t)))
27356 guix build -s armhf-linux inkscape
27360 and it will build Inkscape for ARMv7 @emph{as if it were a native
27361 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
27362 if you'd like to test a package build for an architecture you don't have
27365 @item @code{qemu} (default: @code{qemu})
27366 The QEMU package to use.
27370 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
27371 Return the list of QEMU platform objects corresponding to
27372 @var{platforms}@dots{}. @var{platforms} must be a list of strings
27373 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
27374 @code{"mips64el"}, and so on.
27377 @deffn {Scheme Procedure} qemu-platform? @var{obj}
27378 Return true if @var{obj} is a platform object.
27381 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
27382 Return the name of @var{platform}---a string such as @code{"arm"}.
27386 @subsubheading The Hurd in a Virtual Machine
27388 @cindex @code{hurd}
27392 Service @code{hurd-vm} provides support for running GNU/Hurd in a
27393 virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
27394 to be used on GNU/Linux and the given GNU/Hurd operating system
27395 configuration is cross-compiled. The virtual machine is a Shepherd
27396 service that can be referred to by the names @code{hurd-vm} and
27397 @code{childhurd} and be controlled with commands such as:
27401 herd stop childhurd
27404 When the service is running, you can view its console by connecting to
27405 it with a VNC client, for example with:
27408 guix environment --ad-hoc tigervnc-client -- \
27409 vncviewer localhost:5900
27412 The default configuration (see @code{hurd-vm-configuration} below)
27413 spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
27414 (the virtual machine emulator) redirects to port 10222 on the host.
27415 Thus, you can connect over SSH to the childhurd with:
27418 ssh root@@localhost -p 10022
27421 The childhurd is volatile and stateless: it starts with a fresh root
27422 file system every time you restart it. By default though, all the files
27423 under @file{/etc/childhurd} on the host are copied as is to the root
27424 file system of the childhurd when it boots. This allows you to
27425 initialize ``secrets'' inside the VM: SSH host keys, authorized
27426 substitute keys, and so on---see the explanation of @code{secret-root}
27429 @defvr {Scheme Variable} hurd-vm-service-type
27430 This is the type of the Hurd in a Virtual Machine service. Its value
27431 must be a @code{hurd-vm-configuration} object, which specifies the
27432 operating system (@pxref{operating-system Reference}) and the disk size
27433 for the Hurd Virtual Machine, the QEMU package to use as well as the
27434 options for running it.
27439 (service hurd-vm-service-type
27440 (hurd-vm-configuration
27441 (disk-size (* 5000 (expt 2 20))) ;5G
27442 (memory-size 1024))) ;1024MiB
27445 would create a disk image big enough to build GNU@tie{}Hello, with some
27449 @deftp {Data Type} hurd-vm-configuration
27450 The data type representing the configuration for
27451 @code{hurd-vm-service-type}.
27454 @item @code{os} (default: @var{%hurd-vm-operating-system})
27455 The operating system to instantiate. This default is bare-bones with a
27456 permissive OpenSSH secure shell daemon listening on port 2222
27457 (@pxref{Networking Services, @code{openssh-service-type}}).
27459 @item @code{qemu} (default: @code{qemu-minimal})
27460 The QEMU package to use.
27462 @item @code{image} (default: @var{hurd-vm-disk-image})
27463 The procedure used to build the disk-image built from this
27466 @item @code{disk-size} (default: @code{'guess})
27467 The size of the disk image.
27469 @item @code{memory-size} (default: @code{512})
27470 The memory size of the Virtual Machine in mebibytes.
27472 @item @code{options} (default: @code{'("--snapshot")})
27473 The extra options for running QEMU.
27475 @item @code{id} (default: @code{#f})
27476 If set, a non-zero positive integer used to parameterize Childhurd
27477 instances. It is appended to the service's name,
27478 e.g. @code{childhurd1}.
27480 @item @code{net-options} (default: @var{hurd-vm-net-options})
27481 The procedure used to produce the list of QEMU networking options.
27483 By default, it produces
27486 '("--device" "rtl8139,netdev=net0"
27487 "--netdev" "user,id=net0\
27488 ,hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004\
27489 ,hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222\
27490 ,hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900")
27493 with forwarded ports:
27496 @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
27497 @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
27498 @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
27501 @item @code{secret-root} (default: @file{/etc/childhurd})
27502 The root directory with out-of-band secrets to be installed into the
27503 childhurd once it runs. Childhurds are volatile which means that on
27504 every startup, secrets such as the SSH host keys and Guix signing key
27507 If the @file{/etc/childhurd} directory does not exist, the
27508 @code{secret-service} running in the Childhurd will be sent an empty
27511 By default, the service automatically populates @file{/etc/childhurd}
27512 with the following non-volatile secrets, unless they already exist:
27515 /etc/childhurd/etc/guix/acl
27516 /etc/childhurd/etc/guix/signing-key.pub
27517 /etc/childhurd/etc/guix/signing-key.sec
27518 /etc/childhurd/etc/ssh/ssh_host_ed25519_key
27519 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
27520 /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
27521 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
27524 These files are automatically sent to the guest Hurd VM when it boots,
27525 including permissions.
27527 @cindex childhurd, offloading
27528 @cindex Hurd, offloading
27529 Having these files in place means that only a couple of things are
27530 missing to allow the host to offload @code{i586-gnu} builds to the
27535 Authorizing the childhurd's key on the host so that the host accepts
27536 build results coming from the childhurd, which can be done like so:
27539 guix archive --authorize < \
27540 /etc/childhurd/etc/guix/signing-key.pub
27544 Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
27548 We're working towards making that happen automatically---get in touch
27549 with us at @email{guix-devel@@gnu.org} to discuss it!
27553 Note that by default the VM image is volatile, i.e., once stopped the
27554 contents are lost. If you want a stateful image instead, override the
27555 configuration's @code{image} and @code{options} without
27556 the @code{--snapshot} flag using something along these lines:
27559 (service hurd-vm-service-type
27560 (hurd-vm-configuration
27561 (image (const "/out/of/store/writable/hurd.img"))
27565 @subsubheading Ganeti
27570 This service is considered experimental. Configuration options may be changed
27571 in a backwards-incompatible manner, and not all features have been thorougly
27572 tested. Users of this service are encouraged to share their experience at
27573 @email{guix-devel@@gnu.org}.
27576 Ganeti is a virtual machine management system. It is designed to keep virtual
27577 machines running on a cluster of servers even in the event of hardware failures,
27578 and to make maintenance and recovery tasks easy. It consists of multiple
27579 services which are described later in this section. In addition to the Ganeti
27580 service, you will need the OpenSSH service (@pxref{Networking Services,
27581 @code{openssh-service-type}}), and update the @file{/etc/hosts} file
27582 (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
27583 and address (or use a DNS server).
27585 All nodes participating in a Ganeti cluster should have the same Ganeti and
27586 @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
27587 cluster node that supports multiple storage backends, and installs the
27588 @code{debootstrap} and @code{guix} @dfn{OS providers}:
27591 (use-package-modules virtualization)
27592 (use-service-modules base ganeti networking ssh)
27595 (host-name "node1")
27596 (hosts-file (plain-file "hosts" (format #f "
27597 127.0.0.1 localhost
27600 192.168.1.200 ganeti.example.com
27601 192.168.1.201 node1.example.com node1
27602 192.168.1.202 node2.example.com node2
27605 ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
27606 ;; in order to use the "plain", "drbd" and "rbd" storage backends.
27607 (packages (append (map specification->package
27608 '("qemu" "lvm2" "drbd-utils" "ceph"
27609 ;; Add the debootstrap and guix OS providers.
27610 "ganeti-instance-guix" "ganeti-instance-debootstrap"))
27613 (append (list (static-networking-service "eth0" "192.168.1.201"
27614 #:netmask "255.255.255.0"
27615 #:gateway "192.168.1.254"
27616 #:name-servers '("192.168.1.252"
27619 ;; Ganeti uses SSH to communicate between nodes.
27620 (service openssh-service-type
27621 (openssh-configuration
27622 (permit-root-login 'without-password)))
27624 (service ganeti-service-type
27625 (ganeti-configuration
27626 ;; This list specifies allowed file system paths
27627 ;; for storing virtual machine images.
27628 (file-storage-paths '("/srv/ganeti/file-storage"))
27629 ;; This variable configures a single "variant" for
27630 ;; both Debootstrap and Guix that works with KVM.
27631 (os %default-ganeti-os))))
27635 Users are advised to read the
27636 @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
27637 administrators guide} to learn about the various cluster options and
27638 day-to-day operations. There is also a
27639 @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
27640 describing how to configure and initialize a small cluster.
27642 @defvr {Scheme Variable} ganeti-service-type
27643 This is a service type that includes all the various services that Ganeti
27646 Its value is a @code{ganeti-configuration} object that defines the package
27647 to use for CLI operations, as well as configuration for the various daemons.
27648 Allowed file storage paths and available guest operating systems are also
27649 configured through this data type.
27652 @deftp {Data Type} ganeti-configuration
27653 The @code{ganeti} service takes the following configuration options:
27656 @item @code{ganeti} (default: @code{ganeti})
27657 The @code{ganeti} package to use. It will be installed to the system profile
27658 and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
27659 that the value specified here does not affect the other services as each refer
27660 to a specific @code{ganeti} package (see below).
27662 @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
27663 @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
27664 @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
27665 @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
27666 @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
27667 @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
27668 @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
27669 @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
27670 @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
27671 @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
27673 These options control the various daemons and cron jobs that are distributed
27674 with Ganeti. The possible values for these are described in detail below.
27675 To override a setting, you must use the configuration type for that service:
27678 (service ganeti-service-type
27679 (ganeti-configuration
27680 (rapi-configuration
27681 (ganeti-rapi-configuration
27682 (interface "eth1"))))
27683 (watcher-configuration
27684 (ganeti-watcher-configuration
27685 (rapi-ip "10.0.0.1"))))
27688 @item @code{file-storage-paths} (default: @code{'()})
27689 List of allowed directories for file storage backend.
27691 @item @code{os} (default: @code{%default-ganeti-os})
27692 List of @code{<ganeti-os>} records.
27695 In essence @code{ganeti-service-type} is shorthand for declaring each service
27699 (service ganeti-noded-service-type)
27700 (service ganeti-confd-service-type)
27701 (service ganeti-wconfd-service-type)
27702 (service ganeti-luxid-service-type)
27703 (service ganeti-kvmd-service-type)
27704 (service ganeti-mond-service-type)
27705 (service ganeti-metad-service-type)
27706 (service ganeti-watcher-service-type)
27707 (service ganeti-cleaner-service-type)
27710 Plus a service extension for @code{etc-service-type} that configures the file
27711 storage backend and OS variants.
27715 @deftp {Data Type} ganeti-os
27716 This data type is suitable for passing to the @code{os} parameter of
27717 @code{ganeti-configuration}. It takes the following parameters:
27721 The name for this OS provider. It is only used to specify where the
27722 configuration ends up. Setting it to ``debootstrap'' will create
27723 @file{/etc/ganeti/instance-debootstrap}.
27725 @item @code{extension}
27726 The file extension for variants of this OS type. For example
27727 @file{.conf} or @file{.scm}.
27729 @item @code{variants} (default: @code{'()})
27730 List of @code{ganeti-os-variant} objects for this OS.
27735 @deftp {Data Type} ganeti-os-variant
27736 This is the data type for a Ganeti OS variant. It takes the following
27741 The name of this variant.
27743 @item @code{configuration}
27744 A configuration file for this variant.
27748 @defvr {Scheme Variable} %default-debootstrap-hooks
27749 This variable contains hooks to configure networking and the GRUB bootloader.
27752 @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
27753 This variable contains a list of packages suitable for a fully-virtualized guest.
27756 @deftp {Data Type} debootstrap-configuration
27758 This data type creates configuration files suitable for the debootstrap OS provider.
27761 @item @code{hooks} (default: @code{%default-debootstrap-hooks})
27762 When not @code{#f}, this must be a G-expression that specifies a directory with
27763 scripts that will run when the OS is installed. It can also be a list of
27764 @code{(name . file-like)} pairs. For example:
27767 `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
27770 That will create a directory with one executable named @code{99-hello-world}
27771 and run it every time this variant is installed. If set to @code{#f}, hooks
27772 in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
27773 @item @code{proxy} (default: @code{#f})
27774 Optional HTTP proxy to use.
27775 @item @code{mirror} (default: @code{#f})
27776 The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
27777 The default varies depending on the distribution.
27778 @item @code{arch} (default: @code{#f})
27779 The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
27780 on an AArch64 host. Default is to use the current system architecture.
27781 @item @code{suite} (default: @code{"stable"})
27782 When set, this must be a Debian distribution ``suite'' such as @code{buster}
27783 or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
27784 @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
27785 List of extra packages that will get installed by dpkg in addition
27786 to the minimal system.
27787 @item @code{components} (default: @code{#f})
27788 When set, must be a list of Debian repository ``components''. For example
27789 @code{'("main" "contrib")}.
27790 @item @code{generate-cache?} (default: @code{#t})
27791 Whether to automatically cache the generated debootstrap archive.
27792 @item @code{clean-cache} (default: @code{14})
27793 Discard the cache after this amount of days. Use @code{#f} to never
27795 @item @code{partition-style} (default: @code{'msdos})
27796 The type of partition to create. When set, it must be one of
27797 @code{'msdos}, @code{'none} or a string.
27798 @item @code{partition-alignment} (default: @code{2048})
27799 Alignment of the partition in sectors.
27803 @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
27804 This is a helper procedure that creates a @code{ganeti-os-variant} record. It
27805 takes two parameters: a name and a @code{debootstrap-configuration} object.
27808 @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
27809 This is a helper procedure that creates a @code{ganeti-os} record. It takes
27810 a list of variants created with @code{debootstrap-variant}.
27813 @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
27814 This is a helper procedure that creates a @code{ganeti-os-variant} record for
27815 use with the Guix OS provider. It takes a name and a G-expression that returns
27816 a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
27817 Guix System configuration.
27820 @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
27821 This is a helper procedure that creates a @code{ganeti-os} record. It
27822 takes a list of variants produced by @code{guix-variant}.
27825 @defvr {Scheme Variable} %default-debootstrap-variants
27826 This is a convenience variable to make the debootstrap provider work
27827 ``out of the box'' without users having to declare variants manually. It
27828 contains a single debootstrap variant with the default configuration:
27831 (list (debootstrap-variant
27833 (debootstrap-configuration)))
27837 @defvr {Scheme Variable} %default-guix-variants
27838 This is a convenience variable to make the Guix OS provider work without
27839 additional configuration. It creates a virtual machine that has an SSH
27840 server, a serial console, and authorizes the Ganeti hosts SSH keys.
27843 (list (guix-variant
27845 (file-append ganeti-instance-guix
27846 "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
27850 Users can implement support for OS providers unbeknownst to Guix by extending
27851 the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
27857 (extension ".conf")
27859 (list (ganeti-os-variant
27861 (configuration (plain-file "bar" "this is fine"))))))
27864 That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
27865 to a file in the store with contents @code{this is fine}. It also creates
27866 @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
27868 Obviously this may not work for all OS providers out there. If you find the
27869 interface limiting, please reach out to @email{guix-devel@@gnu.org}.
27871 The rest of this section documents the various services that are included by
27872 @code{ganeti-service-type}.
27874 @defvr {Scheme Variable} ganeti-noded-service-type
27875 @command{ganeti-noded} is the daemon responsible for node-specific functions
27876 within the Ganeti system. The value of this service must be a
27877 @code{ganeti-noded-configuration} object.
27880 @deftp {Data Type} ganeti-noded-configuration
27881 This is the configuration for the @code{ganeti-noded} service.
27884 @item @code{ganeti} (default: @code{ganeti})
27885 The @code{ganeti} package to use for this service.
27887 @item @code{port} (default: @code{1811})
27888 The TCP port on which the node daemon listens for network requests.
27890 @item @code{address} (default: @code{"0.0.0.0"})
27891 The network address that the daemon will bind to. The default address means
27892 bind to all available addresses.
27894 @item @code{interface} (default: @code{#f})
27895 When this is set, it must be a specific network interface (e.g.@: @code{eth0})
27896 that the daemon will bind to.
27898 @item @code{max-clients} (default: @code{20})
27899 This sets a limit on the maximum number of simultaneous client connections
27900 that the daemon will handle. Connections above this count are accepted, but
27901 no responses will be sent until enough connections have closed.
27903 @item @code{ssl?} (default: @code{#t})
27904 Whether to use SSL/TLS to encrypt network communications. The certificate
27905 is automatically provisioned by the cluster and can be rotated with
27906 @command{gnt-cluster renew-crypto}.
27908 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
27909 This can be used to provide a specific encryption key for TLS communications.
27911 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
27912 This can be used to provide a specific certificate for TLS communications.
27914 @item @code{debug?} (default: @code{#f})
27915 When true, the daemon performs additional logging for debugging purposes.
27916 Note that this will leak encryption details to the log files, use with caution.
27921 @defvr {Scheme Variable} ganeti-confd-service-type
27922 @command{ganeti-confd} answers queries related to the configuration of a
27923 Ganeti cluster. The purpose of this daemon is to have a highly available
27924 and fast way to query cluster configuration values. It is automatically
27925 active on all @dfn{master candidates}. The value of this service must be a
27926 @code{ganeti-confd-configuration} object.
27930 @deftp {Data Type} ganeti-confd-configuration
27931 This is the configuration for the @code{ganeti-confd} service.
27934 @item @code{ganeti} (default: @code{ganeti})
27935 The @code{ganeti} package to use for this service.
27937 @item @code{port} (default: @code{1814})
27938 The UDP port on which to listen for network requests.
27940 @item @code{address} (default: @code{"0.0.0.0"})
27941 Network address that the daemon will bind to.
27943 @item @code{debug?} (default: @code{#f})
27944 When true, the daemon performs additional logging for debugging purposes.
27949 @defvr {Scheme Variable} ganeti-wconfd-service-type
27950 @command{ganeti-wconfd} is the daemon that has authoritative knowledge
27951 about the cluster configuration and is the only entity that can accept
27952 changes to it. All jobs that need to modify the configuration will do so
27953 by sending appropriate requests to this daemon. It only runs on the
27954 @dfn{master node} and will automatically disable itself on other nodes.
27956 The value of this service must be a
27957 @code{ganeti-wconfd-configuration} object.
27960 @deftp {Data Type} ganeti-wconfd-configuration
27961 This is the configuration for the @code{ganeti-wconfd} service.
27964 @item @code{ganeti} (default: @code{ganeti})
27965 The @code{ganeti} package to use for this service.
27967 @item @code{no-voting?} (default: @code{#f})
27968 The daemon will refuse to start if the majority of cluster nodes does not
27969 agree that it is running on the master node. Set to @code{#t} to start
27970 even if a quorum can not be reached (dangerous, use with caution).
27972 @item @code{debug?} (default: @code{#f})
27973 When true, the daemon performs additional logging for debugging purposes.
27978 @defvr {Scheme Variable} ganeti-luxid-service-type
27979 @command{ganeti-luxid} is a daemon used to answer queries related to the
27980 configuration and the current live state of a Ganeti cluster. Additionally,
27981 it is the authoritative daemon for the Ganeti job queue. Jobs can be
27982 submitted via this daemon and it schedules and starts them.
27984 It takes a @code{ganeti-luxid-configuration} object.
27987 @deftp {Data Type} ganeti-luxid-configuration
27988 This is the configuration for the @code{ganeti-wconfd} service.
27991 @item @code{ganeti} (default: @code{ganeti})
27992 The @code{ganeti} package to use for this service.
27994 @item @code{no-voting?} (default: @code{#f})
27995 The daemon will refuse to start if it cannot verify that the majority of
27996 cluster nodes believes that it is running on the master node. Set to
27997 @code{#t} to ignore such checks and start anyway (this can be dangerous).
27999 @item @code{debug?} (default: @code{#f})
28000 When true, the daemon performs additional logging for debugging purposes.
28005 @defvr {Scheme Variable} ganeti-rapi-service-type
28006 @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
28007 the master node and can be used to perform cluster actions programmatically
28008 via a JSON-based RPC protocol.
28010 Most query operations are allowed without authentication (unless
28011 @var{require-authentication?} is set), whereas write operations require
28012 explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
28013 the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
28014 API documentation} for more information.
28016 The value of this service must be a @code{ganeti-rapi-configuration} object.
28019 @deftp {Data Type} ganeti-rapi-configuration
28020 This is the configuration for the @code{ganeti-rapi} service.
28023 @item @code{ganeti} (default: @code{ganeti})
28024 The @code{ganeti} package to use for this service.
28026 @item @code{require-authentication?} (default: @code{#f})
28027 Whether to require authentication even for read-only operations.
28029 @item @code{port} (default: @code{5080})
28030 The TCP port on which to listen to API requests.
28032 @item @code{address} (default: @code{"0.0.0.0"})
28033 The network address that the service will bind to. By default it listens
28034 on all configured addresses.
28036 @item @code{interface} (default: @code{#f})
28037 When set, it must specify a specific network interface such as @code{eth0}
28038 that the daemon will bind to.
28040 @item @code{max-clients} (default: @code{20})
28041 The maximum number of simultaneous client requests to handle. Further
28042 connections are allowed, but no responses are sent until enough connections
28045 @item @code{ssl?} (default: @code{#t})
28046 Whether to use SSL/TLS encryption on the RAPI port.
28048 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
28049 This can be used to provide a specific encryption key for TLS communications.
28051 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
28052 This can be used to provide a specific certificate for TLS communications.
28054 @item @code{debug?} (default: @code{#f})
28055 When true, the daemon performs additional logging for debugging purposes.
28056 Note that this will leak encryption details to the log files, use with caution.
28061 @defvr {Scheme Variable} ganeti-kvmd-service-type
28062 @command{ganeti-kvmd} is responsible for determining whether a given KVM
28063 instance was shut down by an administrator or a user. Normally Ganeti will
28064 restart an instance that was not stopped through Ganeti itself. If the
28065 cluster option @code{user_shutdown} is true, this daemon monitors the
28066 @code{QMP} socket provided by QEMU and listens for shutdown events, and
28067 marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
28068 it shuts down gracefully by itself.
28070 It takes a @code{ganeti-kvmd-configuration} object.
28073 @deftp {Data Type} ganeti-kvmd-configuration
28076 @item @code{ganeti} (default: @code{ganeti})
28077 The @code{ganeti} package to use for this service.
28079 @item @code{debug?} (default: @code{#f})
28080 When true, the daemon performs additional logging for debugging purposes.
28085 @defvr {Scheme Variable} ganeti-mond-service-type
28086 @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
28087 functionality. It is responsible for running data collectors and publish the
28088 collected information through a HTTP interface.
28090 It takes a @code{ganeti-mond-configuration} object.
28093 @deftp {Data Type} ganeti-mond-configuration
28096 @item @code{ganeti} (default: @code{ganeti})
28097 The @code{ganeti} package to use for this service.
28099 @item @code{port} (default: @code{1815})
28100 The port on which the daemon will listen.
28102 @item @code{address} (default: @code{"0.0.0.0"})
28103 The network address that the daemon will bind to. By default it binds to all
28104 available interfaces.
28106 @item @code{debug?} (default: @code{#f})
28107 When true, the daemon performs additional logging for debugging purposes.
28112 @defvr {Scheme Variable} ganeti-metad-service-type
28113 @command{ganeti-metad} is an optional daemon that can be used to provide
28114 information about the cluster to instances or OS install scripts.
28116 It takes a @code{ganeti-metad-configuration} object.
28119 @deftp {Data Type} ganeti-metad-configuration
28122 @item @code{ganeti} (default: @code{ganeti})
28123 The @code{ganeti} package to use for this service.
28125 @item @code{port} (default: @code{80})
28126 The port on which the daemon will listen.
28128 @item @code{address} (default: @code{#f})
28129 If set, the daemon will bind to this address only. If left unset, the behavior
28130 depends on the cluster configuration.
28132 @item @code{debug?} (default: @code{#f})
28133 When true, the daemon performs additional logging for debugging purposes.
28138 @defvr {Scheme Variable} ganeti-watcher-service-type
28139 @command{ganeti-watcher} is a script designed to run periodically and ensure
28140 the health of a cluster. It will automatically restart instances that have
28141 stopped without Ganeti's consent, and repairs DRBD links in case a node has
28142 rebooted. It also archives old cluster jobs and restarts Ganeti daemons
28143 that are not running. If the cluster parameter @code{ensure_node_health}
28144 is set, the watcher will also shutdown instances and DRBD devices if the
28145 node it is running on is declared offline by known master candidates.
28147 It can be paused on all nodes with @command{gnt-cluster watcher pause}.
28149 The service takes a @code{ganeti-watcher-configuration} object.
28152 @deftp {Data Type} ganeti-watcher-configuration
28155 @item @code{ganeti} (default: @code{ganeti})
28156 The @code{ganeti} package to use for this service.
28158 @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
28159 How often to run the script. The default is every five minutes.
28161 @item @code{rapi-ip} (default: @code{#f})
28162 This option needs to be specified only if the RAPI daemon is configured to use
28163 a particular interface or address. By default the cluster address is used.
28165 @item @code{job-age} (default: @code{(* 6 3600)})
28166 Archive cluster jobs older than this age, specified in seconds. The default
28167 is 6 hours. This keeps @command{gnt-job list} manageable.
28169 @item @code{verify-disks?} (default: @code{#t})
28170 If this is @code{#f}, the watcher will not try to repair broken DRBD links
28171 automatically. Administrators will need to use @command{gnt-cluster verify-disks}
28174 @item @code{debug?} (default: @code{#f})
28175 When @code{#t}, the script performs additional logging for debugging purposes.
28180 @defvr {Scheme Variable} ganeti-cleaner-service-type
28181 @command{ganeti-cleaner} is a script designed to run periodically and remove
28182 old files from the cluster. This service type controls two @dfn{cron jobs}:
28183 one intended for the master node that permanently purges old cluster jobs,
28184 and one intended for every node that removes expired X509 certificates, keys,
28185 and outdated @command{ganeti-watcher} information. Like all Ganeti services,
28186 it is safe to include even on non-master nodes as it will disable itself as
28189 It takes a @code{ganeti-cleaner-configuration} object.
28192 @deftp {Data Type} ganeti-cleaner-configuration
28195 @item @code{ganeti} (default: @code{ganeti})
28196 The @code{ganeti} package to use for the @command{gnt-cleaner} command.
28198 @item @code{master-schedule} (default: @code{"45 1 * * *"})
28199 How often to run the master cleaning job. The default is once per day, at
28202 @item @code{node-schedule} (default: @code{"45 2 * * *"})
28203 How often to run the node cleaning job. The default is once per day, at
28209 @node Version Control Services
28210 @subsection Version Control Services
28212 The @code{(gnu services version-control)} module provides a service to
28213 allow remote access to local Git repositories. There are three options:
28214 the @code{git-daemon-service}, which provides access to repositories via
28215 the @code{git://} unsecured TCP-based protocol, extending the
28216 @code{nginx} web server to proxy some requests to
28217 @code{git-http-backend}, or providing a web interface with
28218 @code{cgit-service-type}.
28220 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
28222 Return a service that runs @command{git daemon}, a simple TCP server to
28223 expose repositories over the Git protocol for anonymous access.
28225 The optional @var{config} argument should be a
28226 @code{<git-daemon-configuration>} object, by default it allows read-only
28227 access to exported@footnote{By creating the magic file
28228 @file{git-daemon-export-ok} in the repository directory.} repositories under
28233 @deftp {Data Type} git-daemon-configuration
28234 Data type representing the configuration for @code{git-daemon-service}.
28237 @item @code{package} (default: @code{git})
28238 Package object of the Git distributed version control system.
28240 @item @code{export-all?} (default: @code{#f})
28241 Whether to allow access for all Git repositories, even if they do not
28242 have the @file{git-daemon-export-ok} file.
28244 @item @code{base-path} (default: @file{/srv/git})
28245 Whether to remap all the path requests as relative to the given path.
28246 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
28247 @samp{example.com}, then if you later try to pull
28248 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
28249 path as @file{/srv/git/hello.git}.
28251 @item @code{user-path} (default: @code{#f})
28252 Whether to allow @code{~user} notation to be used in requests. When
28253 specified with empty string, requests to
28254 @indicateurl{git://host/~alice/foo} is taken as a request to access
28255 @code{foo} repository in the home directory of user @code{alice}. If
28256 @code{(user-path "@var{path}")} is specified, the same request is taken
28257 as a request to access @file{@var{path}/foo} repository in the home
28258 directory of user @code{alice}.
28260 @item @code{listen} (default: @code{'()})
28261 Whether to listen on specific IP addresses or hostnames, defaults to
28264 @item @code{port} (default: @code{#f})
28265 Whether to listen on an alternative port, which defaults to 9418.
28267 @item @code{whitelist} (default: @code{'()})
28268 If not empty, only allow access to this list of directories.
28270 @item @code{extra-options} (default: @code{'()})
28271 Extra options will be passed to @command{git daemon}, please run
28272 @command{man git-daemon} for more information.
28277 The @code{git://} protocol lacks authentication. When you pull from a
28278 repository fetched via @code{git://}, you don't know whether the data you
28279 receive was modified or is even coming from the specified host, and your
28280 connection is subject to eavesdropping. It's better to use an authenticated
28281 and encrypted transport, such as @code{https}. Although Git allows you
28282 to serve repositories using unsophisticated file-based web servers,
28283 there is a faster protocol implemented by the @code{git-http-backend}
28284 program. This program is the back-end of a proper Git web service. It
28285 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
28286 on running the necessary @code{fcgiwrap} daemon.
28288 Guix has a separate configuration data type for serving Git repositories
28291 @deftp {Data Type} git-http-configuration
28292 Data type representing the configuration for a future
28293 @code{git-http-service-type}; can currently be used to configure Nginx
28294 through @code{git-http-nginx-location-configuration}.
28297 @item @code{package} (default: @var{git})
28298 Package object of the Git distributed version control system.
28300 @item @code{git-root} (default: @file{/srv/git})
28301 Directory containing the Git repositories to expose to the world.
28303 @item @code{export-all?} (default: @code{#f})
28304 Whether to expose access for all Git repositories in @var{git-root},
28305 even if they do not have the @file{git-daemon-export-ok} file.
28307 @item @code{uri-path} (default: @samp{/git/})
28308 Path prefix for Git access. With the default @samp{/git/} prefix, this
28309 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
28310 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
28311 with this prefix are not passed on to this Git instance.
28313 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
28314 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
28319 There is no @code{git-http-service-type}, currently; instead you can
28320 create an @code{nginx-location-configuration} from a
28321 @code{git-http-configuration} and then add that location to a web
28324 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
28325 [config=(git-http-configuration)]
28326 Compute an @code{nginx-location-configuration} that corresponds to the
28327 given Git http configuration. An example nginx service definition to
28328 serve the default @file{/srv/git} over HTTPS might be:
28331 (service nginx-service-type
28332 (nginx-configuration
28335 (nginx-server-configuration
28336 (listen '("443 ssl"))
28337 (server-name "git.my-host.org")
28339 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
28340 (ssl-certificate-key
28341 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
28344 (git-http-nginx-location-configuration
28345 (git-http-configuration (uri-path "/"))))))))))
28348 This example assumes that you are using Let's Encrypt to get your TLS
28349 certificate. @xref{Certificate Services}. The default @code{certbot}
28350 service will redirect all HTTP traffic on @code{git.my-host.org} to
28351 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
28352 system services. @xref{Web Services}.
28355 @subsubheading Cgit Service
28357 @cindex Cgit service
28358 @cindex Git, web interface
28359 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
28360 repositories written in C.
28362 The following example will configure the service with default values.
28363 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
28366 (service cgit-service-type)
28369 The @code{file-object} type designates either a file-like object
28370 (@pxref{G-Expressions, file-like objects}) or a string.
28372 @c %start of fragment
28374 Available @code{cgit-configuration} fields are:
28376 @deftypevr {@code{cgit-configuration} parameter} package package
28381 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
28382 NGINX configuration.
28386 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
28387 Specifies a command which will be invoked to format the content of about
28388 pages (both top-level and for each repository).
28390 Defaults to @samp{""}.
28394 @deftypevr {@code{cgit-configuration} parameter} string agefile
28395 Specifies a path, relative to each repository path, which can be used to
28396 specify the date and time of the youngest commit in the repository.
28398 Defaults to @samp{""}.
28402 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
28403 Specifies a command that will be invoked for authenticating repository
28406 Defaults to @samp{""}.
28410 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
28411 Flag which, when set to @samp{age}, enables date ordering in the branch
28412 ref list, and when set @samp{name} enables ordering by branch name.
28414 Defaults to @samp{"name"}.
28418 @deftypevr {@code{cgit-configuration} parameter} string cache-root
28419 Path used to store the cgit cache entries.
28421 Defaults to @samp{"/var/cache/cgit"}.
28425 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
28426 Number which specifies the time-to-live, in minutes, for the cached
28427 version of repository pages accessed with a fixed SHA1.
28429 Defaults to @samp{-1}.
28433 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
28434 Number which specifies the time-to-live, in minutes, for the cached
28435 version of repository pages accessed without a fixed SHA1.
28437 Defaults to @samp{5}.
28441 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
28442 Number which specifies the time-to-live, in minutes, for the cached
28443 version of the repository summary page.
28445 Defaults to @samp{5}.
28449 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
28450 Number which specifies the time-to-live, in minutes, for the cached
28451 version of the repository index page.
28453 Defaults to @samp{5}.
28457 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
28458 Number which specifies the time-to-live, in minutes, for the result of
28459 scanning a path for Git repositories.
28461 Defaults to @samp{15}.
28465 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
28466 Number which specifies the time-to-live, in minutes, for the cached
28467 version of the repository about page.
28469 Defaults to @samp{15}.
28473 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
28474 Number which specifies the time-to-live, in minutes, for the cached
28475 version of snapshots.
28477 Defaults to @samp{5}.
28481 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
28482 The maximum number of entries in the cgit cache. When set to @samp{0},
28483 caching is disabled.
28485 Defaults to @samp{0}.
28489 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
28490 Sort items in the repo list case sensitively.
28492 Defaults to @samp{#t}.
28496 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
28497 List of common prefixes which, when combined with a repository URL,
28498 generates valid clone URLs for the repository.
28500 Defaults to @samp{()}.
28504 @deftypevr {@code{cgit-configuration} parameter} list clone-url
28505 List of @code{clone-url} templates.
28507 Defaults to @samp{()}.
28511 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
28512 Command which will be invoked to format commit messages.
28514 Defaults to @samp{""}.
28518 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
28519 Flag which, when set to @samp{date}, enables strict date ordering in the
28520 commit log, and when set to @samp{topo} enables strict topological
28523 Defaults to @samp{"git log"}.
28527 @deftypevr {@code{cgit-configuration} parameter} file-object css
28528 URL which specifies the css document to include in all cgit pages.
28530 Defaults to @samp{"/share/cgit/cgit.css"}.
28534 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
28535 Specifies a command which will be invoked to format names and email
28536 address of committers, authors, and taggers, as represented in various
28537 places throughout the cgit interface.
28539 Defaults to @samp{""}.
28543 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
28544 Flag which, when set to @samp{#t}, will make cgit generate a HTML
28545 fragment suitable for embedding in other HTML pages.
28547 Defaults to @samp{#f}.
28551 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
28552 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
28553 commit history graph to the left of the commit messages in the
28554 repository log page.
28556 Defaults to @samp{#f}.
28560 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
28561 Flag which, when set to @samp{#t}, allows all filter settings to be
28562 overridden in repository-specific cgitrc files.
28564 Defaults to @samp{#f}.
28568 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
28569 Flag which, when set to @samp{#t}, allows users to follow a file in the
28572 Defaults to @samp{#f}.
28576 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
28577 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
28580 Defaults to @samp{#t}.
28584 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
28585 Flag which, when set to @samp{#t}, will make cgit generate extra links
28586 "summary", "commit", "tree" for each repo in the repository index.
28588 Defaults to @samp{#f}.
28592 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
28593 Flag which, when set to @samp{#t}, will make cgit display the owner of
28594 each repo in the repository index.
28596 Defaults to @samp{#t}.
28600 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
28601 Flag which, when set to @samp{#t}, will make cgit print the number of
28602 modified files for each commit on the repository log page.
28604 Defaults to @samp{#f}.
28608 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
28609 Flag which, when set to @samp{#t}, will make cgit print the number of
28610 added and removed lines for each commit on the repository log page.
28612 Defaults to @samp{#f}.
28616 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
28617 Flag which, when set to @code{#t}, will make cgit display remote
28618 branches in the summary and refs views.
28620 Defaults to @samp{#f}.
28624 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
28625 Flag which, when set to @code{1}, will make cgit use the subject of the
28626 parent commit as link text when generating links to parent commits in
28629 Defaults to @samp{#f}.
28633 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
28634 Flag which, when set to @samp{#t}, will make cgit use the subject of the
28635 parent commit as link text when generating links to parent commits in
28638 Defaults to @samp{#f}.
28642 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
28643 Flag which, when set to @samp{#t}, will make cgit generate linenumber
28644 links for plaintext blobs printed in the tree view.
28646 Defaults to @samp{#t}.
28650 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
28651 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
28652 set any repo specific settings.
28654 Defaults to @samp{#f}.
28658 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
28659 URL used as link to a shortcut icon for cgit.
28661 Defaults to @samp{"/favicon.ico"}.
28665 @deftypevr {@code{cgit-configuration} parameter} string footer
28666 The content of the file specified with this option will be included
28667 verbatim at the bottom of all pages (i.e.@: it replaces the standard
28668 "generated by..."@: message).
28670 Defaults to @samp{""}.
28674 @deftypevr {@code{cgit-configuration} parameter} string head-include
28675 The content of the file specified with this option will be included
28676 verbatim in the HTML HEAD section on all pages.
28678 Defaults to @samp{""}.
28682 @deftypevr {@code{cgit-configuration} parameter} string header
28683 The content of the file specified with this option will be included
28684 verbatim at the top of all pages.
28686 Defaults to @samp{""}.
28690 @deftypevr {@code{cgit-configuration} parameter} file-object include
28691 Name of a configfile to include before the rest of the current config-
28694 Defaults to @samp{""}.
28698 @deftypevr {@code{cgit-configuration} parameter} string index-header
28699 The content of the file specified with this option will be included
28700 verbatim above the repository index.
28702 Defaults to @samp{""}.
28706 @deftypevr {@code{cgit-configuration} parameter} string index-info
28707 The content of the file specified with this option will be included
28708 verbatim below the heading on the repository index page.
28710 Defaults to @samp{""}.
28714 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
28715 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
28716 in the servers timezone.
28718 Defaults to @samp{#f}.
28722 @deftypevr {@code{cgit-configuration} parameter} file-object logo
28723 URL which specifies the source of an image which will be used as a logo
28726 Defaults to @samp{"/share/cgit/cgit.png"}.
28730 @deftypevr {@code{cgit-configuration} parameter} string logo-link
28731 URL loaded when clicking on the cgit logo image.
28733 Defaults to @samp{""}.
28737 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
28738 Command which will be invoked to format the Owner column of the main
28741 Defaults to @samp{""}.
28745 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
28746 Number of items to display in atom feeds view.
28748 Defaults to @samp{10}.
28752 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
28753 Number of entries to list per page in "log" view.
28755 Defaults to @samp{50}.
28759 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
28760 Number of commit message characters to display in "log" view.
28762 Defaults to @samp{80}.
28766 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
28767 Specifies the number of entries to list per page on the repository index
28770 Defaults to @samp{50}.
28774 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
28775 Specifies the maximum number of repo description characters to display
28776 on the repository index page.
28778 Defaults to @samp{80}.
28782 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
28783 Specifies the maximum size of a blob to display HTML for in KBytes.
28785 Defaults to @samp{0}.
28789 @deftypevr {@code{cgit-configuration} parameter} string max-stats
28790 Maximum statistics period. Valid values are @samp{week},@samp{month},
28791 @samp{quarter} and @samp{year}.
28793 Defaults to @samp{""}.
28797 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
28798 Mimetype for the specified filename extension.
28800 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
28801 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
28802 "image/png") (svg "image/svg+xml"))}.
28806 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
28807 Specifies the file to use for automatic mimetype lookup.
28809 Defaults to @samp{""}.
28813 @deftypevr {@code{cgit-configuration} parameter} string module-link
28814 Text which will be used as the formatstring for a hyperlink when a
28815 submodule is printed in a directory listing.
28817 Defaults to @samp{""}.
28821 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
28822 If set to the value @samp{#t} caching will be disabled.
28824 Defaults to @samp{#f}.
28828 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
28829 If set to @samp{#t} showing full author email addresses will be
28832 Defaults to @samp{#f}.
28836 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
28837 Flag which, when set to @samp{#t}, will make cgit omit the standard
28838 header on all pages.
28840 Defaults to @samp{#f}.
28844 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
28845 A list of subdirectories inside of @code{repository-directory}, relative
28846 to it, that should loaded as Git repositories. An empty list means that
28847 all subdirectories will be loaded.
28849 Defaults to @samp{()}.
28853 @deftypevr {@code{cgit-configuration} parameter} file-object readme
28854 Text which will be used as default value for @code{cgit-repo-readme}.
28856 Defaults to @samp{""}.
28860 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
28861 If set to @code{#t} and @code{repository-directory} is enabled, if any
28862 repositories are found with a suffix of @code{.git}, this suffix will be
28863 removed for the URL and name.
28865 Defaults to @samp{#f}.
28869 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
28870 Maximum number of files to consider when detecting renames.
28872 Defaults to @samp{-1}.
28876 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
28877 The way in which repositories in each section are sorted.
28879 Defaults to @samp{""}.
28883 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
28884 Text used as content for the @code{robots} meta-tag.
28886 Defaults to @samp{("noindex" "nofollow")}.
28890 @deftypevr {@code{cgit-configuration} parameter} string root-desc
28891 Text printed below the heading on the repository index page.
28893 Defaults to @samp{"a fast webinterface for the git dscm"}.
28897 @deftypevr {@code{cgit-configuration} parameter} string root-readme
28898 The content of the file specified with this option will be included
28899 verbatim below the ``about'' link on the repository index page.
28901 Defaults to @samp{""}.
28905 @deftypevr {@code{cgit-configuration} parameter} string root-title
28906 Text printed as heading on the repository index page.
28908 Defaults to @samp{""}.
28912 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
28913 If set to @samp{#t} and repository-directory is enabled,
28914 repository-directory will recurse into directories whose name starts
28915 with a period. Otherwise, repository-directory will stay away from such
28916 directories, considered as ``hidden''. Note that this does not apply to
28917 the @file{.git} directory in non-bare repos.
28919 Defaults to @samp{#f}.
28923 @deftypevr {@code{cgit-configuration} parameter} list snapshots
28924 Text which specifies the default set of snapshot formats that cgit
28925 generates links for.
28927 Defaults to @samp{()}.
28931 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
28932 Name of the directory to scan for repositories (represents
28935 Defaults to @samp{"/srv/git"}.
28939 @deftypevr {@code{cgit-configuration} parameter} string section
28940 The name of the current repository section - all repositories defined
28941 after this option will inherit the current section name.
28943 Defaults to @samp{""}.
28947 @deftypevr {@code{cgit-configuration} parameter} string section-sort
28948 Flag which, when set to @samp{1}, will sort the sections on the
28949 repository listing by name.
28951 Defaults to @samp{""}.
28955 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
28956 A number which, if defined prior to repository-directory, specifies how
28957 many path elements from each repo path to use as a default section name.
28959 Defaults to @samp{0}.
28963 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
28964 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
28967 Defaults to @samp{#f}.
28971 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
28972 Specifies a command which will be invoked to format plaintext blobs in
28975 Defaults to @samp{""}.
28979 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
28980 Specifies the number of branches to display in the repository ``summary''
28983 Defaults to @samp{10}.
28987 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
28988 Specifies the number of log entries to display in the repository
28991 Defaults to @samp{10}.
28995 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
28996 Specifies the number of tags to display in the repository ``summary''
28999 Defaults to @samp{10}.
29003 @deftypevr {@code{cgit-configuration} parameter} string strict-export
29004 Filename which, if specified, needs to be present within the repository
29005 for cgit to allow access to that repository.
29007 Defaults to @samp{""}.
29011 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
29012 URL which, if specified, will be used as root for all cgit links.
29014 Defaults to @samp{"/"}.
29018 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
29019 A list of @dfn{cgit-repo} records to use with config.
29021 Defaults to @samp{()}.
29023 Available @code{repository-cgit-configuration} fields are:
29025 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
29026 A mask of snapshot formats for this repo that cgit generates links for,
29027 restricted by the global @code{snapshots} setting.
29029 Defaults to @samp{()}.
29033 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
29034 Override the default @code{source-filter}.
29036 Defaults to @samp{""}.
29040 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
29041 The relative URL used to access the repository.
29043 Defaults to @samp{""}.
29047 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
29048 Override the default @code{about-filter}.
29050 Defaults to @samp{""}.
29054 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
29055 Flag which, when set to @samp{age}, enables date ordering in the branch
29056 ref list, and when set to @samp{name} enables ordering by branch name.
29058 Defaults to @samp{""}.
29062 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
29063 A list of URLs which can be used to clone repo.
29065 Defaults to @samp{()}.
29069 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
29070 Override the default @code{commit-filter}.
29072 Defaults to @samp{""}.
29076 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
29077 Flag which, when set to @samp{date}, enables strict date ordering in the
29078 commit log, and when set to @samp{topo} enables strict topological
29081 Defaults to @samp{""}.
29085 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
29086 The name of the default branch for this repository. If no such branch
29087 exists in the repository, the first branch name (when sorted) is used as
29088 default instead. By default branch pointed to by HEAD, or ``master'' if
29089 there is no suitable HEAD.
29091 Defaults to @samp{""}.
29095 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
29096 The value to show as repository description.
29098 Defaults to @samp{""}.
29102 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
29103 The value to show as repository homepage.
29105 Defaults to @samp{""}.
29109 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
29110 Override the default @code{email-filter}.
29112 Defaults to @samp{""}.
29116 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
29117 A flag which can be used to disable the global setting
29118 @code{enable-commit-graph?}.
29120 Defaults to @samp{disabled}.
29124 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
29125 A flag which can be used to disable the global setting
29126 @code{enable-log-filecount?}.
29128 Defaults to @samp{disabled}.
29132 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
29133 A flag which can be used to disable the global setting
29134 @code{enable-log-linecount?}.
29136 Defaults to @samp{disabled}.
29140 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
29141 Flag which, when set to @code{#t}, will make cgit display remote
29142 branches in the summary and refs views.
29144 Defaults to @samp{disabled}.
29148 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
29149 A flag which can be used to override the global setting
29150 @code{enable-subject-links?}.
29152 Defaults to @samp{disabled}.
29156 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
29157 A flag which can be used to override the global setting
29158 @code{enable-html-serving?}.
29160 Defaults to @samp{disabled}.
29164 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
29165 Flag which, when set to @code{#t}, hides the repository from the
29168 Defaults to @samp{#f}.
29172 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
29173 Flag which, when set to @samp{#t}, ignores the repository.
29175 Defaults to @samp{#f}.
29179 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
29180 URL which specifies the source of an image which will be used as a logo
29181 on this repo’s pages.
29183 Defaults to @samp{""}.
29187 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
29188 URL loaded when clicking on the cgit logo image.
29190 Defaults to @samp{""}.
29194 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
29195 Override the default @code{owner-filter}.
29197 Defaults to @samp{""}.
29201 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
29202 Text which will be used as the formatstring for a hyperlink when a
29203 submodule is printed in a directory listing. The arguments for the
29204 formatstring are the path and SHA1 of the submodule commit.
29206 Defaults to @samp{""}.
29210 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
29211 Text which will be used as the formatstring for a hyperlink when a
29212 submodule with the specified subdirectory path is printed in a directory
29215 Defaults to @samp{()}.
29219 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
29220 Override the default maximum statistics period.
29222 Defaults to @samp{""}.
29226 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
29227 The value to show as repository name.
29229 Defaults to @samp{""}.
29233 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
29234 A value used to identify the owner of the repository.
29236 Defaults to @samp{""}.
29240 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
29241 An absolute path to the repository directory.
29243 Defaults to @samp{""}.
29247 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
29248 A path (relative to repo) which specifies a file to include verbatim as
29249 the ``About'' page for this repo.
29251 Defaults to @samp{""}.
29255 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
29256 The name of the current repository section - all repositories defined
29257 after this option will inherit the current section name.
29259 Defaults to @samp{""}.
29263 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
29264 Extra options will be appended to cgitrc file.
29266 Defaults to @samp{()}.
29272 @deftypevr {@code{cgit-configuration} parameter} list extra-options
29273 Extra options will be appended to cgitrc file.
29275 Defaults to @samp{()}.
29280 @c %end of fragment
29282 However, it could be that you just want to get a @code{cgitrc} up and
29283 running. In that case, you can pass an @code{opaque-cgit-configuration}
29284 as a record to @code{cgit-service-type}. As its name indicates, an
29285 opaque configuration does not have easy reflective capabilities.
29287 Available @code{opaque-cgit-configuration} fields are:
29289 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
29293 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
29294 The contents of the @code{cgitrc}, as a string.
29297 For example, if your @code{cgitrc} is just the empty string, you
29298 could instantiate a cgit service like this:
29301 (service cgit-service-type
29302 (opaque-cgit-configuration
29306 @subsubheading Gitolite Service
29308 @cindex Gitolite service
29309 @cindex Git, hosting
29310 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
29311 repositories on a central server.
29313 Gitolite can handle multiple repositories and users, and supports flexible
29314 configuration of the permissions for the users on the repositories.
29316 The following example will configure Gitolite using the default @code{git}
29317 user, and the provided SSH public key.
29320 (service gitolite-service-type
29321 (gitolite-configuration
29322 (admin-pubkey (plain-file
29324 "ssh-rsa AAAA... guix@@example.com"))))
29327 Gitolite is configured through a special admin repository which you can clone,
29328 for example, if you setup Gitolite on @code{example.com}, you would run the
29329 following command to clone the admin repository.
29332 git clone git@@example.com:gitolite-admin
29335 When the Gitolite service is activated, the provided @code{admin-pubkey} will
29336 be inserted in to the @file{keydir} directory in the gitolite-admin
29337 repository. If this results in a change in the repository, it will be
29338 committed using the message ``gitolite setup by GNU Guix''.
29340 @deftp {Data Type} gitolite-configuration
29341 Data type representing the configuration for @code{gitolite-service-type}.
29344 @item @code{package} (default: @var{gitolite})
29345 Gitolite package to use.
29347 @item @code{user} (default: @var{git})
29348 User to use for Gitolite. This will be user that you use when accessing
29351 @item @code{group} (default: @var{git})
29352 Group to use for Gitolite.
29354 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
29355 Directory in which to store the Gitolite configuration and repositories.
29357 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
29358 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
29359 representing the configuration for Gitolite.
29361 @item @code{admin-pubkey} (default: @var{#f})
29362 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
29363 setup Gitolite. This will be inserted in to the @file{keydir} directory
29364 within the gitolite-admin repository.
29366 To specify the SSH key as a string, use the @code{plain-file} function.
29369 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
29375 @deftp {Data Type} gitolite-rc-file
29376 Data type representing the Gitolite RC file.
29379 @item @code{umask} (default: @code{#o0077})
29380 This controls the permissions Gitolite sets on the repositories and their
29383 A value like @code{#o0027} will give read access to the group used by Gitolite
29384 (by default: @code{git}). This is necessary when using Gitolite with software
29385 like cgit or gitweb.
29387 @item @code{git-config-keys} (default: @code{""})
29388 Gitolite allows you to set git config values using the @samp{config}
29389 keyword. This setting allows control over the config keys to accept.
29391 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
29392 Set the role names allowed to be used by users running the perms command.
29394 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
29395 This setting controls the commands and features to enable within Gitolite.
29401 @node Game Services
29402 @subsection Game Services
29404 @subsubheading The Battle for Wesnoth Service
29406 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
29407 based tactical strategy game, with several single player campaigns, and
29408 multiplayer games (both networked and local).
29410 @defvar {Scheme Variable} wesnothd-service-type
29411 Service type for the wesnothd service. Its value must be a
29412 @code{wesnothd-configuration} object. To run wesnothd in the default
29413 configuration, instantiate it as:
29416 (service wesnothd-service-type)
29420 @deftp {Data Type} wesnothd-configuration
29421 Data type representing the configuration of @command{wesnothd}.
29424 @item @code{package} (default: @code{wesnoth-server})
29425 The wesnoth server package to use.
29427 @item @code{port} (default: @code{15000})
29428 The port to bind the server to.
29433 @node PAM Mount Service
29434 @subsection PAM Mount Service
29437 The @code{(gnu services pam-mount)} module provides a service allowing
29438 users to mount volumes when they log in. It should be able to mount any
29439 volume format supported by the system.
29441 @defvar {Scheme Variable} pam-mount-service-type
29442 Service type for PAM Mount support.
29445 @deftp {Data Type} pam-mount-configuration
29446 Data type representing the configuration of PAM Mount.
29448 It takes the following parameters:
29452 The configuration rules that will be used to generate
29453 @file{/etc/security/pam_mount.conf.xml}.
29455 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
29456 Guile Reference Manual}), and the default ones don't mount anything for
29460 `((debug (@@ (enable "0")))
29461 (mntoptions (@@ (allow ,(string-join
29462 '("nosuid" "nodev" "loop"
29463 "encryption" "fsck" "nonempty"
29464 "allow_root" "allow_other")
29466 (mntoptions (@@ (require "nosuid,nodev")))
29467 (logout (@@ (wait "0")
29471 (mkmountpoint (@@ (enable "1")
29475 Some @code{volume} elements must be added to automatically mount volumes
29476 at login. Here's an example allowing the user @code{alice} to mount her
29477 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
29478 the partition where he stores his data:
29481 (define pam-mount-rules
29482 `((debug (@@ (enable "0")))
29483 (volume (@@ (user "alice")
29486 (mountpoint "/home/alice")))
29487 (volume (@@ (user "bob")
29490 (mountpoint "/home/bob/data")
29491 (options "defaults,autodefrag,compress")))
29492 (mntoptions (@@ (allow ,(string-join
29493 '("nosuid" "nodev" "loop"
29494 "encryption" "fsck" "nonempty"
29495 "allow_root" "allow_other")
29497 (mntoptions (@@ (require "nosuid,nodev")))
29498 (logout (@@ (wait "0")
29502 (mkmountpoint (@@ (enable "1")
29503 (remove "true")))))
29505 (service pam-mount-service-type
29506 (pam-mount-configuration
29507 (rules pam-mount-rules)))
29510 The complete list of possible options can be found in the man page for
29511 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
29516 @node Guix Services
29517 @subsection Guix Services
29519 @subsubheading Guix Build Coordinator
29520 The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
29521 Coordinator} aids in distributing derivation builds among machines
29522 running an @dfn{agent}. The build daemon is still used to build the
29523 derivations, but the Guix Build Coordinator manages allocating builds
29524 and working with the results.
29527 This service is considered experimental. Configuration options may be
29528 changed in a backwards-incompatible manner, and not all features have
29529 been thorougly tested.
29532 The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
29533 more connected @dfn{agent} processes. The coordinator process handles
29534 clients submitting builds, and allocating builds to agents. The agent
29535 processes talk to a build daemon to actually perform the builds, then
29536 send the results back to the coordinator.
29538 There is a script to run the coordinator component of the Guix Build
29539 Coordinator, but the Guix service uses a custom Guile script instead, to
29540 provide better integration with G-expressions used in the configuration.
29542 @defvar {Scheme Variable} guix-build-coordinator-service-type
29543 Service type for the Guix Build Coordinator. Its value must be a
29544 @code{guix-build-coordinator-configuration} object.
29547 @deftp {Data Type} guix-build-coordinator-configuration
29548 Data type representing the configuration of the Guix Build Coordinator.
29551 @item @code{package} (default: @code{guix-build-coordinator})
29552 The Guix Build Coordinator package to use.
29554 @item @code{user} (default: @code{"guix-build-coordinator"})
29555 The system user to run the service as.
29557 @item @code{group} (default: @code{"guix-build-coordinator"})
29558 The system group to run the service as.
29560 @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
29561 The URI to use for the database.
29563 @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
29564 The URI describing how to listen to requests from agent processes.
29566 @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
29567 The URI describing how to listen to requests from clients. The client
29568 API allows submitting builds and currently isn't authenticated, so take
29569 care when configuring this value.
29571 @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
29572 A G-expression for the allocation strategy to be used. This is a
29573 procedure that takes the datastore as an argument and populates the
29574 allocation plan in the database.
29576 @item @code{hooks} (default: @var{'()})
29577 An association list of hooks. These provide a way to execute arbitrary
29578 code upon certain events, like a build result being processed.
29580 @item @code{guile} (default: @code{guile-3.0-latest})
29581 The Guile package with which to run the Guix Build Coordinator.
29586 @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
29587 Service type for a Guix Build Coordinator agent. Its value must be a
29588 @code{guix-build-coordinator-agent-configuration} object.
29591 @deftp {Data Type} guix-build-coordinator-agent-configuration
29592 Data type representing the configuration a Guix Build Coordinator agent.
29595 @item @code{package} (default: @code{guix-build-coordinator})
29596 The Guix Build Coordinator package to use.
29598 @item @code{user} (default: @code{"guix-build-coordinator-agent"})
29599 The system user to run the service as.
29601 @item @code{coordinator} (default: @code{"http://localhost:8745"})
29602 The URI to use when connecting to the coordinator.
29605 The UUID of the agent. This should be generated by the coordinator
29606 process, stored in the coordinator database, and used by the intended
29609 @item @code{password} (default: @code{#f})
29610 The password to use when connecting to the coordinator. A file to read
29611 the password from can also be specified, and this is more secure.
29613 @item @code{password-file} (default: @code{#f})
29614 A file containing the password to use when connecting to the
29617 @item @code{systems} (default: @code{#f})
29618 The systems for which this agent should fetch builds. The agent process
29619 will use the current system it's running on as the default.
29621 @item @code{max-parallel-builds} (default: @code{1})
29622 The number of builds to perform in parallel.
29624 @item @code{derivation-substitute-urls} (default: @code{#f})
29625 URLs from which to attempt to fetch substitutes for derivations, if the
29626 derivations aren't already available.
29628 @item @code{non-derivation-substitute-urls} (default: @code{#f})
29629 URLs from which to attempt to fetch substitutes for build inputs, if the
29630 input store items aren't already available.
29635 The Guix Build Coordinator package contains a script to query an
29636 instance of the Guix Data Service for derivations to build, and then
29637 submit builds for those derivations to the coordinator. The service
29638 type below assists in running this script. This is an additional tool
29639 that may be useful when building derivations contained within an
29640 instance of the Guix Data Service.
29642 @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
29643 Service type for the
29644 guix-build-coordinator-queue-builds-from-guix-data-service script. Its
29645 value must be a @code{guix-build-coordinator-queue-builds-configuration}
29649 @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
29650 Data type representing the options to the queue builds from guix data
29654 @item @code{package} (default: @code{guix-build-coordinator})
29655 The Guix Build Coordinator package to use.
29657 @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
29658 The system user to run the service as.
29660 @item @code{coordinator} (default: @code{"http://localhost:8745"})
29661 The URI to use when connecting to the coordinator.
29663 @item @code{systems} (default: @code{#f})
29664 The systems for which to fetch derivations to build.
29666 @item @code{systems-and-targets} (default: @code{#f})
29667 An association list of system and target pairs for which to fetch
29668 derivations to build.
29670 @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
29671 The Guix Data Service instance from which to query to find out about
29672 derivations to build.
29674 @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
29675 A file to record which commits have been processed, to avoid needlessly
29676 processing them again if the service is restarted.
29681 @subsubheading Guix Data Service
29682 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
29683 and provides data about GNU Guix. This includes information about
29684 packages, derivations and lint warnings.
29686 The data is stored in a PostgreSQL database, and available through a web
29689 @defvar {Scheme Variable} guix-data-service-type
29690 Service type for the Guix Data Service. Its value must be a
29691 @code{guix-data-service-configuration} object. The service optionally
29692 extends the getmail service, as the guix-commits mailing list is used to
29693 find out about changes in the Guix git repository.
29696 @deftp {Data Type} guix-data-service-configuration
29697 Data type representing the configuration of the Guix Data Service.
29700 @item @code{package} (default: @code{guix-data-service})
29701 The Guix Data Service package to use.
29703 @item @code{user} (default: @code{"guix-data-service"})
29704 The system user to run the service as.
29706 @item @code{group} (default: @code{"guix-data-service"})
29707 The system group to run the service as.
29709 @item @code{port} (default: @code{8765})
29710 The port to bind the web service to.
29712 @item @code{host} (default: @code{"127.0.0.1"})
29713 The host to bind the web service to.
29715 @item @code{getmail-idle-mailboxes} (default: @code{#f})
29716 If set, this is the list of mailboxes that the getmail service will be
29717 configured to listen to.
29719 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
29720 If set, this is the @code{getmail-retriever-configuration} object with
29721 which to configure getmail to fetch mail from the guix-commits mailing
29724 @item @code{extra-options} (default: @var{'()})
29725 Extra command line options for @code{guix-data-service}.
29727 @item @code{extra-process-jobs-options} (default: @var{'()})
29728 Extra command line options for @code{guix-data-service-process-jobs}.
29733 @node Linux Services
29734 @subsection Linux Services
29737 @cindex out of memory killer
29739 @cindex early out of memory daemon
29740 @subsubheading Early OOM Service
29742 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
29743 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
29744 space and provides a more responsive and configurable alternative to the
29745 in-kernel OOM killer. It is useful to prevent the system from becoming
29746 unresponsive when it runs out of memory.
29748 @deffn {Scheme Variable} earlyoom-service-type
29749 The service type for running @command{earlyoom}, the Early OOM daemon.
29750 Its value must be a @code{earlyoom-configuration} object, described
29751 below. The service can be instantiated in its default configuration
29755 (service earlyoom-service-type)
29759 @deftp {Data Type} earlyoom-configuration
29760 This is the configuration record for the @code{earlyoom-service-type}.
29763 @item @code{earlyoom} (default: @var{earlyoom})
29764 The Earlyoom package to use.
29766 @item @code{minimum-available-memory} (default: @code{10})
29767 The threshold for the minimum @emph{available} memory, in percentages.
29769 @item @code{minimum-free-swap} (default: @code{10})
29770 The threshold for the minimum free swap memory, in percentages.
29772 @item @code{prefer-regexp} (default: @code{#f})
29773 A regular expression (as a string) to match the names of the processes
29774 that should be preferably killed.
29776 @item @code{avoid-regexp} (default: @code{#f})
29777 A regular expression (as a string) to match the names of the processes
29778 that should @emph{not} be killed.
29780 @item @code{memory-report-interval} (default: @code{0})
29781 The interval in seconds at which a memory report is printed. It is
29782 disabled by default.
29784 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
29785 A boolean indicating whether the positive adjustments set in
29786 @file{/proc/*/oom_score_adj} should be ignored.
29788 @item @code{show-debug-messages?} (default: @code{#f})
29789 A boolean indicating whether debug messages should be printed. The logs
29790 are saved at @file{/var/log/earlyoom.log}.
29792 @item @code{send-notification-command} (default: @code{#f})
29793 This can be used to provide a custom command used for sending
29799 @cindex kernel module loader
29800 @subsubheading Kernel Module Loader Service
29802 The kernel module loader service allows one to load loadable kernel
29803 modules at boot. This is especially useful for modules that don't
29804 autoload and need to be manually loaded, as it's the case with
29807 @deffn {Scheme Variable} kernel-module-loader-service-type
29808 The service type for loading loadable kernel modules at boot with
29809 @command{modprobe}. Its value must be a list of strings representing
29810 module names. For example loading the drivers provided by
29811 @code{ddcci-driver-linux}, in debugging mode by passing some module
29812 parameters, can be done as follow:
29815 (use-modules (gnu) (gnu services))
29816 (use-package-modules linux)
29817 (use-service-modules linux)
29819 (define ddcci-config
29820 (plain-file "ddcci.conf"
29821 "options ddcci dyndbg delay=120"))
29825 (services (cons* (service kernel-module-loader-service-type
29826 '("ddcci" "ddcci_backlight"))
29827 (simple-service 'ddcci-config etc-service-type
29828 (list `("modprobe.d/ddcci.conf"
29831 (kernel-loadable-modules (list ddcci-driver-linux)))
29836 @cindex compressed swap
29837 @cindex Compressed RAM-based block devices
29838 @subsubheading Zram Device Service
29840 The Zram device service provides a compressed swap device in system
29841 memory. The Linux Kernel documentation has more information about
29842 @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
29845 @deffn {Scheme Variable} zram-device-service-type
29846 This service creates the zram block device, formats it as swap and
29847 enables it as a swap device. The service's value is a
29848 @code{zram-device-configuration} record.
29850 @deftp {Data Type} zram-device-configuration
29851 This is the data type representing the configuration for the zram-device
29855 @item @code{size} (default @code{"1G"})
29856 This is the amount of space you wish to provide for the zram device. It
29857 accepts a string and can be a number of bytes or use a suffix, eg.:
29858 @code{"512M"} or @code{1024000}.
29859 @item @code{compression-algorithm} (default @code{'lzo})
29860 This is the compression algorithm you wish to use. It is difficult to
29861 list all the possible compression options, but common ones supported by
29862 Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
29863 @item @code{memory-limit} (default @code{0})
29864 This is the maximum amount of memory which the zram device can use.
29865 Setting it to '0' disables the limit. While it is generally expected
29866 that compression will be 2:1, it is possible that uncompressable data
29867 can be written to swap and this is a method to limit how much memory can
29868 be used. It accepts a string and can be a number of bytes or use a
29869 suffix, eg.: @code{"2G"}.
29870 @item @code{priority} (default @code{-1})
29871 This is the priority of the swap device created from the zram device.
29872 @code{swapon} accepts values between -1 and 32767, with higher values
29873 indicating higher priority. Higher priority swap will generally be used
29880 @node Hurd Services
29881 @subsection Hurd Services
29883 @defvr {Scheme Variable} hurd-console-service-type
29884 This service starts the fancy @code{VGA} console client on the Hurd.
29886 The service's value is a @code{hurd-console-configuration} record.
29889 @deftp {Data Type} hurd-console-configuration
29890 This is the data type representing the configuration for the
29891 hurd-console-service.
29894 @item @code{hurd} (default: @var{hurd})
29895 The Hurd package to use.
29899 @defvr {Scheme Variable} hurd-getty-service-type
29900 This service starts a tty using the Hurd @code{getty} program.
29902 The service's value is a @code{hurd-getty-configuration} record.
29905 @deftp {Data Type} hurd-getty-configuration
29906 This is the data type representing the configuration for the
29907 hurd-getty-service.
29910 @item @code{hurd} (default: @var{hurd})
29911 The Hurd package to use.
29914 The name of the console this Getty runs on---e.g., @code{"tty1"}.
29916 @item @code{baud-rate} (default: @code{38400})
29917 An integer specifying the baud rate of the tty.
29922 @node Miscellaneous Services
29923 @subsection Miscellaneous Services
29925 @cindex fingerprint
29926 @subsubheading Fingerprint Service
29928 The @code{(gnu services authentication)} module provides a DBus service to
29929 read and identify fingerprints via a fingerprint sensor.
29931 @defvr {Scheme Variable} fprintd-service-type
29932 The service type for @command{fprintd}, which provides the fingerprint
29933 reading capability.
29936 (service fprintd-service-type)
29941 @subsubheading System Control Service
29943 The @code{(gnu services sysctl)} provides a service to configure kernel
29944 parameters at boot.
29946 @defvr {Scheme Variable} sysctl-service-type
29947 The service type for @command{sysctl}, which modifies kernel parameters
29948 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
29952 (service sysctl-service-type
29953 (sysctl-configuration
29954 (settings '(("net.ipv4.ip_forward" . "1")))))
29958 @deftp {Data Type} sysctl-configuration
29959 The data type representing the configuration of @command{sysctl}.
29962 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
29963 The @command{sysctl} executable to use.
29965 @item @code{settings} (default: @code{'()})
29966 An association list specifies kernel parameters and their values.
29971 @subsubheading PC/SC Smart Card Daemon Service
29973 The @code{(gnu services security-token)} module provides the following service
29974 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
29975 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
29976 manager that coordinates communications with smart card readers, smart cards
29977 and cryptographic tokens that are connected to the system.
29979 @defvr {Scheme Variable} pcscd-service-type
29980 Service type for the @command{pcscd} service. Its value must be a
29981 @code{pcscd-configuration} object. To run pcscd in the default
29982 configuration, instantiate it as:
29985 (service pcscd-service-type)
29989 @deftp {Data Type} pcscd-configuration
29990 The data type representing the configuration of @command{pcscd}.
29993 @item @code{pcsc-lite} (default: @code{pcsc-lite})
29994 The pcsc-lite package that provides pcscd.
29995 @item @code{usb-drivers} (default: @code{(list ccid)})
29996 List of packages that provide USB drivers to pcscd. Drivers are expected to be
29997 under @file{pcsc/drivers} in the store directory of the package.
30002 @subsubheading Lirc Service
30004 The @code{(gnu services lirc)} module provides the following service.
30006 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
30007 [#:device #f] [#:driver #f] [#:config-file #f] @
30008 [#:extra-options '()]
30009 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
30010 decodes infrared signals from remote controls.
30012 Optionally, @var{device}, @var{driver} and @var{config-file}
30013 (configuration file name) may be specified. See @command{lircd} manual
30016 Finally, @var{extra-options} is a list of additional command-line options
30017 passed to @command{lircd}.
30021 @subsubheading Spice Service
30023 The @code{(gnu services spice)} module provides the following service.
30025 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
30026 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
30027 that enables sharing the clipboard with a vm and setting the guest display
30028 resolution when the graphical console window resizes.
30031 @cindex inputattach
30032 @subsubheading inputattach Service
30034 @cindex tablet input, for Xorg
30035 @cindex touchscreen input, for Xorg
30036 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
30037 use input devices such as Wacom tablets, touchscreens, or joysticks with the
30038 Xorg display server.
30040 @deffn {Scheme Variable} inputattach-service-type
30041 Type of a service that runs @command{inputattach} on a device and
30042 dispatches events from it.
30045 @deftp {Data Type} inputattach-configuration
30047 @item @code{device-type} (default: @code{"wacom"})
30048 The type of device to connect to. Run @command{inputattach --help}, from the
30049 @code{inputattach} package, to see the list of supported device types.
30051 @item @code{device} (default: @code{"/dev/ttyS0"})
30052 The device file to connect to the device.
30054 @item @code{baud-rate} (default: @code{#f})
30055 Baud rate to use for the serial connection.
30056 Should be a number or @code{#f}.
30058 @item @code{log-file} (default: @code{#f})
30059 If true, this must be the name of a file to log messages to.
30063 @subsubheading Dictionary Service
30065 The @code{(gnu services dict)} module provides the following service:
30067 @defvr {Scheme Variable} dicod-service-type
30068 This is the type of the service that runs the @command{dicod} daemon, an
30069 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
30072 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
30073 Return a service that runs the @command{dicod} daemon, an implementation
30074 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
30076 The optional @var{config} argument specifies the configuration for
30077 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
30078 default it serves the GNU Collaborative International Dictionary of English.
30080 You can add @command{open localhost} to your @file{~/.dico} file to make
30081 @code{localhost} the default server for @command{dico} client
30082 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
30085 @deftp {Data Type} dicod-configuration
30086 Data type representing the configuration of dicod.
30089 @item @code{dico} (default: @var{dico})
30090 Package object of the GNU Dico dictionary server.
30092 @item @code{interfaces} (default: @var{'("localhost")})
30093 This is the list of IP addresses and ports and possibly socket file
30094 names to listen to (@pxref{Server Settings, @code{listen} directive,,
30095 dico, GNU Dico Manual}).
30097 @item @code{handlers} (default: @var{'()})
30098 List of @code{<dicod-handler>} objects denoting handlers (module instances).
30100 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
30101 List of @code{<dicod-database>} objects denoting dictionaries to be served.
30105 @deftp {Data Type} dicod-handler
30106 Data type representing a dictionary handler (module instance).
30110 Name of the handler (module instance).
30112 @item @code{module} (default: @var{#f})
30113 Name of the dicod module of the handler (instance). If it is @code{#f},
30114 the module has the same name as the handler.
30115 (@pxref{Modules,,, dico, GNU Dico Manual}).
30117 @item @code{options}
30118 List of strings or gexps representing the arguments for the module handler
30122 @deftp {Data Type} dicod-database
30123 Data type representing a dictionary database.
30127 Name of the database, will be used in DICT commands.
30129 @item @code{handler}
30130 Name of the dicod handler (module instance) used by this database
30131 (@pxref{Handlers,,, dico, GNU Dico Manual}).
30133 @item @code{complex?} (default: @var{#f})
30134 Whether the database configuration complex. The complex configuration
30135 will need a corresponding @code{<dicod-handler>} object, otherwise not.
30137 @item @code{options}
30138 List of strings or gexps representing the arguments for the database
30139 (@pxref{Databases,,, dico, GNU Dico Manual}).
30143 @defvr {Scheme Variable} %dicod-database:gcide
30144 A @code{<dicod-database>} object serving the GNU Collaborative International
30145 Dictionary of English using the @code{gcide} package.
30148 The following is an example @code{dicod-service} configuration.
30151 (dicod-service #:config
30152 (dicod-configuration
30153 (handlers (list (dicod-handler
30157 (list #~(string-append "dbdir=" #$wordnet))))))
30158 (databases (list (dicod-database
30161 (handler "wordnet")
30162 (options '("database=wn")))
30163 %dicod-database:gcide))))
30167 @subsubheading Docker Service
30169 The @code{(gnu services docker)} module provides the following services.
30171 @defvr {Scheme Variable} docker-service-type
30173 This is the type of the service that runs @url{https://www.docker.com,Docker},
30174 a daemon that can execute application bundles (sometimes referred to as
30175 ``containers'') in isolated environments.
30179 @deftp {Data Type} docker-configuration
30180 This is the data type representing the configuration of Docker and Containerd.
30184 @item @code{package} (default: @code{docker})
30185 The Docker daemon package to use.
30187 @item @code{package} (default: @code{docker-cli})
30188 The Docker client package to use.
30190 @item @code{containerd} (default: @var{containerd})
30191 The Containerd package to use.
30193 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
30194 The Docker user-land networking proxy package to use.
30196 @item @code{enable-proxy?} (default @code{#t})
30197 Enable or disable the use of the Docker user-land networking proxy.
30199 @item @code{debug?} (default @code{#f})
30200 Enable or disable debug output.
30202 @item @code{enable-iptables?} (default @code{#t})
30203 Enable or disable the addition of iptables rules.
30208 @cindex Singularity, container service
30209 @defvr {Scheme Variable} singularity-service-type
30210 This is the type of the service that allows you to run
30211 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
30212 create and run application bundles (aka. ``containers''). The value for this
30213 service is the Singularity package to use.
30215 The service does not install a daemon; instead, it installs helper programs as
30216 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
30217 @command{singularity run} and similar commands.
30221 @subsubheading Auditd Service
30223 The @code{(gnu services auditd)} module provides the following service.
30225 @defvr {Scheme Variable} auditd-service-type
30227 This is the type of the service that runs
30228 @url{https://people.redhat.com/sgrubb/audit/,auditd},
30229 a daemon that tracks security-relevant information on your system.
30231 Examples of things that can be tracked:
30241 Failed login attempts
30248 @command{auditctl} from the @code{audit} package can be used in order
30249 to add or remove events to be tracked (until the next reboot).
30250 In order to permanently track events, put the command line arguments
30251 of auditctl into a file called @code{audit.rules} in the configuration
30252 directory (see below).
30253 @command{aureport} from the @code{audit} package can be used in order
30254 to view a report of all recorded events.
30255 The audit daemon by default logs into the file
30256 @file{/var/log/audit.log}.
30260 @deftp {Data Type} auditd-configuration
30261 This is the data type representing the configuration of auditd.
30265 @item @code{audit} (default: @code{audit})
30266 The audit package to use.
30268 @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
30269 The directory containing the configuration file for the audit package, which
30270 must be named @code{auditd.conf}, and optionally some audit rules to
30271 instantiate on startup.
30277 @subsubheading R-Shiny service
30279 The @code{(gnu services science)} module provides the following service.
30281 @defvr {Scheme Variable} rshiny-service-type
30283 This is a type of service which is used to run a webapp created with
30284 @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
30285 variable and runs the provided script to call @code{runApp}.
30287 @deftp {Data Type} rshiny-configuration
30288 This is the data type representing the configuration of rshiny.
30292 @item @code{package} (default: @code{r-shiny})
30293 The package to use.
30295 @item @code{binary} (defaunlt @code{"rshiny"})
30296 The name of the binary or shell script located at @code{package/bin/} to
30297 run when the service is run.
30299 The common way to create this file is as follows:
30303 (let* ((out (assoc-ref %outputs "out"))
30304 (targetdir (string-append out "/share/" ,name))
30305 (app (string-append out "/bin/" ,name))
30306 (Rbin (string-append (assoc-ref %build-inputs "r-min")
30309 (mkdir-p (string-append out "/bin"))
30310 (call-with-output-file app
30316 runApp(launch.browser=0, port=4202)~%\n"
30325 @subsubheading Nix service
30327 The @code{(gnu services nix)} module provides the following service.
30329 @defvr {Scheme Variable} nix-service-type
30331 This is the type of the service that runs build daemon of the
30332 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
30336 (use-modules (gnu))
30337 (use-service-modules nix)
30338 (use-package-modules package-management)
30342 (packages (append (list nix)
30345 (services (append (list (service nix-service-type))
30349 After @command{guix system reconfigure} configure Nix for your user:
30352 @item Add a Nix channel and update it. See
30353 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
30355 @item Create a symlink to your profile and activate Nix profile:
30359 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
30360 $ source /run/current-system/profile/etc/profile.d/nix.sh
30365 @deftp {Data Type} nix-configuration
30366 This data type represents the configuration of the Nix daemon.
30369 @item @code{nix} (default: @code{nix})
30370 The Nix package to use.
30372 @item @code{sandbox} (default: @code{#t})
30373 Specifies whether builds are sandboxed by default.
30375 @item @code{build-sandbox-items} (default: @code{'()})
30376 This is a list of strings or objects appended to the
30377 @code{build-sandbox-items} field of the configuration file.
30379 @item @code{extra-config} (default: @code{'()})
30380 This is a list of strings or objects appended to the configuration file.
30381 It is used to pass extra text to be added verbatim to the configuration
30384 @item @code{extra-options} (default: @code{'()})
30385 Extra command line options for @code{nix-service-type}.
30389 @node Setuid Programs
30390 @section Setuid Programs
30392 @cindex setuid programs
30393 Some programs need to run with ``root'' privileges, even when they are
30394 launched by unprivileged users. A notorious example is the
30395 @command{passwd} program, which users can run to change their
30396 password, and which needs to access the @file{/etc/passwd} and
30397 @file{/etc/shadow} files---something normally restricted to root, for
30398 obvious security reasons. To address that, these executables are
30399 @dfn{setuid-root}, meaning that they always run with root privileges
30400 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
30401 for more info about the setuid mechanism).
30403 The store itself @emph{cannot} contain setuid programs: that would be a
30404 security issue since any user on the system can write derivations that
30405 populate the store (@pxref{The Store}). Thus, a different mechanism is
30406 used: instead of changing the setuid bit directly on files that are in
30407 the store, we let the system administrator @emph{declare} which programs
30408 should be setuid root.
30410 The @code{setuid-programs} field of an @code{operating-system}
30411 declaration contains a list of G-expressions denoting the names of
30412 programs to be setuid-root (@pxref{Using the Configuration System}).
30413 For instance, the @command{passwd} program, which is part of the Shadow
30414 package, can be designated by this G-expression (@pxref{G-Expressions}):
30417 #~(string-append #$shadow "/bin/passwd")
30420 A default set of setuid programs is defined by the
30421 @code{%setuid-programs} variable of the @code{(gnu system)} module.
30423 @defvr {Scheme Variable} %setuid-programs
30424 A list of G-expressions denoting common programs that are setuid-root.
30426 The list includes commands such as @command{passwd}, @command{ping},
30427 @command{su}, and @command{sudo}.
30430 Under the hood, the actual setuid programs are created in the
30431 @file{/run/setuid-programs} directory at system activation time. The
30432 files in this directory refer to the ``real'' binaries, which are in the
30435 @node X.509 Certificates
30436 @section X.509 Certificates
30438 @cindex HTTPS, certificates
30439 @cindex X.509 certificates
30441 Web servers available over HTTPS (that is, HTTP over the transport-layer
30442 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
30443 that the client can then use to @emph{authenticate} the server. To do
30444 that, clients verify that the server's certificate is signed by a
30445 so-called @dfn{certificate authority} (CA). But to verify the CA's
30446 signature, clients must have first acquired the CA's certificate.
30448 Web browsers such as GNU@tie{}IceCat include their own set of CA
30449 certificates, such that they are able to verify CA signatures
30452 However, most other programs that can talk HTTPS---@command{wget},
30453 @command{git}, @command{w3m}, etc.---need to be told where CA
30454 certificates can be found.
30456 @cindex @code{nss-certs}
30457 In Guix, this is done by adding a package that provides certificates
30458 to the @code{packages} field of the @code{operating-system} declaration
30459 (@pxref{operating-system Reference}). Guix includes one such package,
30460 @code{nss-certs}, which is a set of CA certificates provided as part of
30461 Mozilla's Network Security Services.
30463 Note that it is @emph{not} part of @code{%base-packages}, so you need to
30464 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
30465 most applications and libraries look for certificates by default, points
30466 to the certificates installed globally.
30468 Unprivileged users, including users of Guix on a foreign distro,
30469 can also install their own certificate package in
30470 their profile. A number of environment variables need to be defined so
30471 that applications and libraries know where to find them. Namely, the
30472 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
30473 variables. Some applications add their own environment variables; for
30474 instance, the Git version control system honors the certificate bundle
30475 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
30476 would typically run something like:
30479 guix install nss-certs
30480 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
30481 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
30482 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
30485 As another example, R requires the @env{CURL_CA_BUNDLE} environment
30486 variable to point to a certificate bundle, so you would have to run
30487 something like this:
30490 guix install nss-certs
30491 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
30494 For other applications you may want to look up the required environment
30495 variable in the relevant documentation.
30498 @node Name Service Switch
30499 @section Name Service Switch
30501 @cindex name service switch
30503 The @code{(gnu system nss)} module provides bindings to the
30504 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
30505 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
30506 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
30507 extended with new ``name'' lookup methods for system databases, which
30508 includes host names, service names, user accounts, and more (@pxref{Name
30509 Service Switch, System Databases and Name Service Switch,, libc, The GNU
30510 C Library Reference Manual}).
30512 The NSS configuration specifies, for each system database, which lookup
30513 method is to be used, and how the various methods are chained
30514 together---for instance, under which circumstances NSS should try the
30515 next method in the list. The NSS configuration is given in the
30516 @code{name-service-switch} field of @code{operating-system} declarations
30517 (@pxref{operating-system Reference, @code{name-service-switch}}).
30520 @cindex .local, host name lookup
30521 As an example, the declaration below configures the NSS to use the
30522 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
30523 back-end}, which supports host name lookups over multicast DNS (mDNS)
30524 for host names ending in @code{.local}:
30527 (name-service-switch
30528 (hosts (list %files ;first, check /etc/hosts
30530 ;; If the above did not succeed, try
30531 ;; with 'mdns_minimal'.
30533 (name "mdns_minimal")
30535 ;; 'mdns_minimal' is authoritative for
30536 ;; '.local'. When it returns "not found",
30537 ;; no need to try the next methods.
30538 (reaction (lookup-specification
30539 (not-found => return))))
30541 ;; Then fall back to DNS.
30545 ;; Finally, try with the "full" 'mdns'.
30550 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
30551 contains this configuration, so you will not have to type it if all you
30552 want is to have @code{.local} host lookup working.
30554 Note that, in this case, in addition to setting the
30555 @code{name-service-switch} of the @code{operating-system} declaration,
30556 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
30557 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
30558 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
30559 to the name service cache daemon (@pxref{Base Services,
30560 @code{nscd-service}}).
30562 For convenience, the following variables provide typical NSS
30565 @defvr {Scheme Variable} %default-nss
30566 This is the default name service switch configuration, a
30567 @code{name-service-switch} object.
30570 @defvr {Scheme Variable} %mdns-host-lookup-nss
30571 This is the name service switch configuration with support for host name
30572 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
30575 The reference for name service switch configuration is given below. It
30576 is a direct mapping of the configuration file format of the C library , so
30577 please refer to the C library manual for more information (@pxref{NSS
30578 Configuration File,,, libc, The GNU C Library Reference Manual}).
30579 Compared to the configuration file format of libc NSS, it has the advantage
30580 not only of adding this warm parenthetic feel that we like, but also
30581 static checks: you will know about syntax errors and typos as soon as you
30582 run @command{guix system}.
30584 @deftp {Data Type} name-service-switch
30586 This is the data type representation the configuration of libc's name
30587 service switch (NSS). Each field below represents one of the supported
30604 The system databases handled by the NSS. Each of these fields must be a
30605 list of @code{<name-service>} objects (see below).
30609 @deftp {Data Type} name-service
30611 This is the data type representing an actual name service and the
30612 associated lookup action.
30616 A string denoting the name service (@pxref{Services in the NSS
30617 configuration,,, libc, The GNU C Library Reference Manual}).
30619 Note that name services listed here must be visible to nscd. This is
30620 achieved by passing the @code{#:name-services} argument to
30621 @code{nscd-service} the list of packages providing the needed name
30622 services (@pxref{Base Services, @code{nscd-service}}).
30625 An action specified using the @code{lookup-specification} macro
30626 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
30627 Reference Manual}). For example:
30630 (lookup-specification (unavailable => continue)
30631 (success => return))
30636 @node Initial RAM Disk
30637 @section Initial RAM Disk
30640 @cindex initial RAM disk
30641 For bootstrapping purposes, the Linux-Libre kernel is passed an
30642 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
30643 root file system as well as an initialization script. The latter is
30644 responsible for mounting the real root file system, and for loading any
30645 kernel modules that may be needed to achieve that.
30647 The @code{initrd-modules} field of an @code{operating-system}
30648 declaration allows you to specify Linux-libre kernel modules that must
30649 be available in the initrd. In particular, this is where you would list
30650 modules needed to actually drive the hard disk where your root partition
30651 is---although the default value of @code{initrd-modules} should cover
30652 most use cases. For example, assuming you need the @code{megaraid_sas}
30653 module in addition to the default modules to be able to access your root
30654 file system, you would write:
30659 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
30662 @defvr {Scheme Variable} %base-initrd-modules
30663 This is the list of kernel modules included in the initrd by default.
30666 Furthermore, if you need lower-level customization, the @code{initrd}
30667 field of an @code{operating-system} declaration allows
30668 you to specify which initrd you would like to use. The @code{(gnu
30669 system linux-initrd)} module provides three ways to build an initrd: the
30670 high-level @code{base-initrd} procedure and the low-level
30671 @code{raw-initrd} and @code{expression->initrd} procedures.
30673 The @code{base-initrd} procedure is intended to cover most common uses.
30674 For example, if you want to add a bunch of kernel modules to be loaded
30675 at boot time, you can define the @code{initrd} field of the operating
30676 system declaration like this:
30679 (initrd (lambda (file-systems . rest)
30680 ;; Create a standard initrd but set up networking
30681 ;; with the parameters QEMU expects by default.
30682 (apply base-initrd file-systems
30683 #:qemu-networking? #t
30687 The @code{base-initrd} procedure also handles common use cases that
30688 involves using the system as a QEMU guest, or as a ``live'' system with
30689 volatile root file system.
30691 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
30692 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
30693 such as trying to guess which kernel modules and packages should be included
30694 to the initrd. An example use of @code{raw-initrd} is when a user has
30695 a custom Linux kernel configuration and default kernel modules included by
30696 @code{base-initrd} are not available.
30698 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
30699 honors several options passed on the Linux kernel command line
30700 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
30701 @code{-append} option of QEMU), notably:
30704 @item --load=@var{boot}
30705 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
30706 program, once it has mounted the root file system.
30708 Guix uses this option to yield control to a boot program that runs the
30709 service activation programs and then spawns the GNU@tie{}Shepherd, the
30710 initialization system.
30712 @item --root=@var{root}
30713 Mount @var{root} as the root file system. @var{root} can be a device
30714 name like @code{/dev/sda1}, a file system label, or a file system UUID.
30715 When unspecified, the device name from the root file system of the
30716 operating system declaration is used.
30718 @item --system=@var{system}
30719 Have @file{/run/booted-system} and @file{/run/current-system} point to
30722 @item modprobe.blacklist=@var{modules}@dots{}
30723 @cindex module, black-listing
30724 @cindex black list, of kernel modules
30725 Instruct the initial RAM disk as well as the @command{modprobe} command
30726 (from the kmod package) to refuse to load @var{modules}. @var{modules}
30727 must be a comma-separated list of module names---e.g.,
30728 @code{usbkbd,9pnet}.
30731 Start a read-eval-print loop (REPL) from the initial RAM disk before it
30732 tries to load kernel modules and to mount the root file system. Our
30733 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
30734 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
30735 Manual}, for more information on Guile's REPL.
30739 Now that you know all the features that initial RAM disks produced by
30740 @code{base-initrd} and @code{raw-initrd} provide,
30741 here is how to use it and customize it further.
30744 @cindex initial RAM disk
30745 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
30746 [#:linux-modules '()] [#:mapped-devices '()] @
30747 [#:keyboard-layout #f] @
30748 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
30749 Return a derivation that builds a raw initrd. @var{file-systems} is
30750 a list of file systems to be mounted by the initrd, possibly in addition to
30751 the root file system specified on the kernel command line via @option{--root}.
30752 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
30753 @var{mapped-devices} is a list of device mappings to realize before
30754 @var{file-systems} are mounted (@pxref{Mapped Devices}).
30755 @var{helper-packages} is a list of packages to be copied in the initrd.
30757 include @code{e2fsck/static} or other packages needed by the initrd to check
30758 the root file system.
30760 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
30761 the desired console keyboard layout. This is done before @var{mapped-devices}
30762 are set up and before @var{file-systems} are mounted such that, should the
30763 user need to enter a passphrase or use the REPL, this happens using the
30764 intended keyboard layout.
30766 When @var{qemu-networking?} is true, set up networking with the standard QEMU
30767 parameters. When @var{virtio?} is true, load additional modules so that the
30768 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
30770 When @var{volatile-root?} is true, the root file system is writable but any changes
30774 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
30775 [#:mapped-devices '()] [#:keyboard-layout #f] @
30776 [#:qemu-networking? #f] [#:volatile-root? #f] @
30777 [#:linux-modules '()]
30778 Return as a file-like object a generic initrd, with kernel
30779 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
30780 mounted by the initrd, possibly in addition to the root file system specified
30781 on the kernel command line via @option{--root}. @var{mapped-devices} is a list of device
30782 mappings to realize before @var{file-systems} are mounted.
30784 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
30785 the desired console keyboard layout. This is done before @var{mapped-devices}
30786 are set up and before @var{file-systems} are mounted such that, should the
30787 user need to enter a passphrase or use the REPL, this happens using the
30788 intended keyboard layout.
30790 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
30792 The initrd is automatically populated with all the kernel modules necessary
30793 for @var{file-systems} and for the given options. Additional kernel
30794 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
30795 loaded at boot time in the order in which they appear.
30798 Needless to say, the initrds we produce and use embed a
30799 statically-linked Guile, and the initialization program is a Guile
30800 program. That gives a lot of flexibility. The
30801 @code{expression->initrd} procedure builds such an initrd, given the
30802 program to run in that initrd.
30804 @deffn {Scheme Procedure} expression->initrd @var{exp} @
30805 [#:guile %guile-3.0-static-stripped] [#:name "guile-initrd"]
30806 Return as a file-like object a Linux initrd (a gzipped cpio archive)
30807 containing @var{guile} and that evaluates @var{exp}, a G-expression,
30808 upon booting. All the derivations referenced by @var{exp} are
30809 automatically copied to the initrd.
30812 @node Bootloader Configuration
30813 @section Bootloader Configuration
30816 @cindex boot loader
30818 The operating system supports multiple bootloaders. The bootloader is
30819 configured using @code{bootloader-configuration} declaration. All the
30820 fields of this structure are bootloader agnostic except for one field,
30821 @code{bootloader} that indicates the bootloader to be configured and
30824 Some of the bootloaders do not honor every field of
30825 @code{bootloader-configuration}. For instance, the extlinux
30826 bootloader does not support themes and thus ignores the @code{theme}
30829 @deftp {Data Type} bootloader-configuration
30830 The type of a bootloader configuration declaration.
30834 @item @code{bootloader}
30835 @cindex EFI, bootloader
30836 @cindex UEFI, bootloader
30837 @cindex BIOS, bootloader
30838 The bootloader to use, as a @code{bootloader} object. For now
30839 @code{grub-bootloader}, @code{grub-efi-bootloader},
30840 @code{grub-efi-netboot-bootloader}, @code{extlinux-bootloader} and
30841 @code{u-boot-bootloader} are supported.
30843 @cindex ARM, bootloaders
30844 @cindex AArch64, bootloaders
30845 Available bootloaders are described in @code{(gnu bootloader @dots{})}
30846 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
30847 of bootloaders for a wide range of ARM and AArch64 systems, using the
30848 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
30850 @vindex grub-efi-bootloader
30851 @code{grub-efi-bootloader} allows to boot on modern systems using the
30852 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
30853 use if the installation image contains a @file{/sys/firmware/efi} directory
30854 when you boot it on your system.
30856 @vindex grub-bootloader
30857 @code{grub-bootloader} allows you to boot in particular Intel-based machines
30858 in ``legacy'' BIOS mode.
30860 @vindex grub-efi-netboot-bootloader
30861 @code{grub-efi-netboot-bootloader} allows you to boot your system over network
30862 through TFTP. In combination with an NFS root file system this allows you to
30863 build a diskless Guix system.
30865 The installation of the @code{grub-efi-netboot-bootloader} generates the content
30866 of the TFTP root directory at @code{target}
30867 (@pxref{Bootloader Configuration, @code{target}}), to be served by a TFTP server.
30868 You may want to mount your TFTP server directory onto @code{target} to move the
30869 required files to the TFTP server automatically.
30871 If you plan to use an NFS root file system as well (actually if you mount the
30872 store from an NFS share), then the TFTP server needs to serve the file
30873 @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
30874 image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
30875 initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
30876 files from the store will be accessed by GRUB through TFTP with their normal
30877 store path, for example as
30878 @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
30880 Two symlinks are created to make this possible. The first symlink is
30881 @code{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
30882 @file{../../../boot/grub/grub.cfg},
30883 where @code{target} may be @file{/boot}. In this case the link is not leaving
30884 the served TFTP root directory, but otherwise it does. The second link is
30885 @code{target}@file{/gnu/store} and points to @file{../gnu/store}. This link
30886 is leaving the served TFTP root directory.
30888 The assumption behind all this is that you have an NFS server exporting the root
30889 file system for your Guix system, and additionally a TFTP server exporting your
30890 @code{target} directory—usually @file{/boot}—from that same root file system for
30891 your Guix system. In this constellation the symlinks will work.
30893 For other constellations you will have to program your own bootloader installer,
30894 which then takes care to make necessary files from the store accessible through
30895 TFTP, for example by copying them into the TFTP root directory at @code{target}.
30897 It is important to note that symlinks pointing outside the TFTP root directory
30898 may need to be allowed in the configuration of your TFTP server. Further the
30899 store link exposes the whole store through TFTP. Both points need to be
30900 considered carefully for security aspects.
30902 Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
30903 NFS servers, you also need a properly configured DHCP server to make the booting
30904 over netboot possible. For all this we can currently only recommend you to look
30905 for instructions about @acronym{PXE, Preboot eXecution Environment}.
30907 @item @code{target}
30908 This is a string denoting the target onto which to install the
30911 The interpretation depends on the bootloader in question. For
30912 @code{grub-bootloader}, for example, it should be a device name understood by
30913 the bootloader @command{installer} command, such as @code{/dev/sda} or
30914 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
30915 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
30916 system, usually @file{/boot/efi}. For @code{grub-efi-netboot-bootloader},
30917 @code{target} should be the mount point corresponding to the TFTP root
30918 directory of your TFTP server.
30920 @item @code{menu-entries} (default: @code{()})
30921 A possibly empty list of @code{menu-entry} objects (see below), denoting
30922 entries to appear in the bootloader menu, in addition to the current
30923 system entry and the entry pointing to previous system generations.
30925 @item @code{default-entry} (default: @code{0})
30926 The index of the default boot menu entry. Index 0 is for the entry of the
30929 @item @code{timeout} (default: @code{5})
30930 The number of seconds to wait for keyboard input before booting. Set to
30931 0 to boot immediately, and to -1 to wait indefinitely.
30933 @cindex keyboard layout, for the bootloader
30934 @item @code{keyboard-layout} (default: @code{#f})
30935 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
30936 layout, usually US@tie{}English (``qwerty'').
30938 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
30942 This option is currently ignored by bootloaders other than @code{grub} and
30946 @item @code{theme} (default: @var{#f})
30947 The bootloader theme object describing the theme to use. If no theme
30948 is provided, some bootloaders might use a default theme, that's true
30951 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
30952 The output terminals used for the bootloader boot menu, as a list of
30953 symbols. GRUB accepts the values: @code{console}, @code{serial},
30954 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
30955 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
30956 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
30957 configuration,,, grub,GNU GRUB manual}).
30959 @item @code{terminal-inputs} (default: @code{'()})
30960 The input terminals used for the bootloader boot menu, as a list of
30961 symbols. For GRUB, the default is the native platform terminal as
30962 determined at run-time. GRUB accepts the values: @code{console},
30963 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
30964 @code{usb_keyboard}. This field corresponds to the GRUB variable
30965 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
30968 @item @code{serial-unit} (default: @code{#f})
30969 The serial unit used by the bootloader, as an integer from 0 to 3.
30970 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
30971 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
30973 @item @code{serial-speed} (default: @code{#f})
30974 The speed of the serial interface, as an integer. For GRUB, the
30975 default value is chosen at run-time; currently GRUB chooses
30976 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
30983 Should you want to list additional boot menu entries @i{via} the
30984 @code{menu-entries} field above, you will need to create them with the
30985 @code{menu-entry} form. For example, imagine you want to be able to
30986 boot another distro (hard to imagine!), you can define a menu entry
30991 (label "The Other Distro")
30992 (linux "/boot/old/vmlinux-2.6.32")
30993 (linux-arguments '("root=/dev/sda2"))
30994 (initrd "/boot/old/initrd"))
30999 @deftp {Data Type} menu-entry
31000 The type of an entry in the bootloader menu.
31005 The label to show in the menu---e.g., @code{"GNU"}.
31007 @item @code{linux} (default: @code{#f})
31008 The Linux kernel image to boot, for example:
31011 (file-append linux-libre "/bzImage")
31014 For GRUB, it is also possible to specify a device explicitly in the
31015 file path using GRUB's device naming convention (@pxref{Naming
31016 convention,,, grub, GNU GRUB manual}), for example:
31019 "(hd0,msdos1)/boot/vmlinuz"
31022 If the device is specified explicitly as above, then the @code{device}
31023 field is ignored entirely.
31025 @item @code{linux-arguments} (default: @code{()})
31026 The list of extra Linux kernel command-line arguments---e.g.,
31027 @code{("console=ttyS0")}.
31029 @item @code{initrd} (default: @code{#f})
31030 A G-Expression or string denoting the file name of the initial RAM disk
31031 to use (@pxref{G-Expressions}).
31033 @item @code{device} (default: @code{#f})
31034 The device where the kernel and initrd are to be found---i.e., for GRUB,
31035 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
31037 This may be a file system label (a string), a file system UUID (a
31038 bytevector, @pxref{File Systems}), or @code{#f}, in which case
31039 the bootloader will search the device containing the file specified by
31040 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
31041 must @emph{not} be an OS device name such as @file{/dev/sda1}.
31043 @item @code{multiboot-kernel} (default: @code{#f})
31044 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
31045 manual}). When this field is set, a Multiboot menu-entry is generated.
31049 (file-append mach "/boot/gnumach")
31052 @item @code{multiboot-arguments} (default: @code{()})
31053 The list of extra command-line arguments for the multiboot-kernel.
31055 @item @code{multiboot-modules} (default: @code{()})
31056 The list of commands for loading Multiboot modules. For example:
31059 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
31061 (list (file-append libc "/lib/ld.so.1") "exec"
31071 @c FIXME: Write documentation once it's stable.
31072 For now only GRUB has theme support. GRUB themes are created using
31073 the @code{grub-theme} form, which is not fully documented yet.
31075 @deftp {Data Type} grub-theme
31076 Data type representing the configuration of the GRUB theme.
31079 @item @code{gfxmode} (default: @code{'("auto")})
31080 The GRUB @code{gfxmode} to set (a list of screen resolution strings,
31081 @pxref{gfxmode,,, grub, GNU GRUB manual}).
31085 @deffn {Scheme Procedure} grub-theme
31086 Return the default GRUB theme used by the operating system if no
31087 @code{theme} field is specified in @code{bootloader-configuration}
31090 It comes with a fancy background image displaying the GNU and Guix
31094 For example, to override the default resolution, you may use something
31099 (bootloader-configuration
31102 (inherit (grub-theme))
31103 (gfxmode '("1024x786x32" "auto"))))))
31106 @node Invoking guix system
31107 @section Invoking @code{guix system}
31109 Once you have written an operating system declaration as seen in the
31110 previous section, it can be @dfn{instantiated} using the @command{guix
31111 system} command. The synopsis is:
31114 guix system @var{options}@dots{} @var{action} @var{file}
31117 @var{file} must be the name of a file containing an
31118 @code{operating-system} declaration. @var{action} specifies how the
31119 operating system is instantiated. Currently the following values are
31124 Display available service type definitions that match the given regular
31125 expressions, sorted by relevance:
31131 $ guix system search console
31132 name: console-fonts
31133 location: gnu/services/base.scm:806:2
31134 extends: shepherd-root
31135 description: Install the given fonts on the specified ttys (fonts are per
31136 + virtual console on GNU/Linux). The value of this service is a list of
31137 + tty/font pairs. The font can be the name of a font provided by the `kbd'
31138 + package or any valid argument to `setfont', as in this example:
31140 + '(("tty1" . "LatGrkCyr-8x16")
31141 + ("tty2" . (file-append
31143 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
31144 + ("tty3" . (file-append
31146 + "/share/consolefonts/ter-132n"))) ; for HDPI
31150 location: gnu/services/base.scm:1190:2
31151 extends: shepherd-root
31152 description: Provide console login using the `mingetty' program.
31156 location: gnu/services/base.scm:860:2
31158 description: Provide a console log-in service as specified by its
31159 + configuration value, a `login-configuration' object.
31165 As for @command{guix package --search}, the result is written in
31166 @code{recutils} format, which makes it easy to filter the output
31167 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
31170 Build the operating system described in @var{file}, activate it, and
31171 switch to it@footnote{This action (and the related actions
31172 @code{switch-generation} and @code{roll-back}) are usable only on
31173 systems already running Guix System.}.
31176 @c The paragraph below refers to the problem discussed at
31177 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
31178 It is highly recommended to run @command{guix pull} once before you run
31179 @command{guix system reconfigure} for the first time (@pxref{Invoking
31180 guix pull}). Failing to do that you would see an older version of Guix
31181 once @command{reconfigure} has completed.
31184 This effects all the configuration specified in @var{file}: user
31185 accounts, system services, global package list, setuid programs, etc.
31186 The command starts system services specified in @var{file} that are not
31187 currently running; if a service is currently running this command will
31188 arrange for it to be upgraded the next time it is stopped (e.g.@: by
31189 @code{herd stop X} or @code{herd restart X}).
31191 This command creates a new generation whose number is one greater than
31192 the current generation (as reported by @command{guix system
31193 list-generations}). If that generation already exists, it will be
31194 overwritten. This behavior mirrors that of @command{guix package}
31195 (@pxref{Invoking guix package}).
31197 It also adds a bootloader menu entry for the new OS configuration,
31198 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
31199 entries for older configurations to a submenu, allowing you to choose
31200 an older system generation at boot time should you need it.
31202 @cindex provenance tracking, of the operating system
31203 Upon completion, the new system is deployed under
31204 @file{/run/current-system}. This directory contains @dfn{provenance
31205 meta-data}: the list of channels in use (@pxref{Channels}) and
31206 @var{file} itself, when available. You can view it by running:
31209 guix system describe
31212 This information is useful should you later want to inspect how this
31213 particular generation was built. In fact, assuming @var{file} is
31214 self-contained, you can later rebuild generation @var{n} of your
31215 operating system with:
31218 guix time-machine \
31219 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
31220 system reconfigure \
31221 /var/guix/profiles/system-@var{n}-link/configuration.scm
31224 You can think of it as some sort of built-in version control! Your
31225 system is not just a binary artifact: @emph{it carries its own source}.
31226 @xref{Service Reference, @code{provenance-service-type}}, for more
31227 information on provenance tracking.
31229 By default, @command{reconfigure} @emph{prevents you from downgrading
31230 your system}, which could (re)introduce security vulnerabilities and
31231 also cause problems with ``stateful'' services such as database
31232 management systems. You can override that behavior by passing
31233 @option{--allow-downgrades}.
31235 @item switch-generation
31236 @cindex generations
31237 Switch to an existing system generation. This action atomically
31238 switches the system profile to the specified system generation. It
31239 also rearranges the system's existing bootloader menu entries. It
31240 makes the menu entry for the specified system generation the default,
31241 and it moves the entries for the other generations to a submenu, if
31242 supported by the bootloader being used. The next time the system
31243 boots, it will use the specified system generation.
31245 The bootloader itself is not being reinstalled when using this
31246 command. Thus, the installed bootloader is used with an updated
31247 configuration file.
31249 The target generation can be specified explicitly by its generation
31250 number. For example, the following invocation would switch to system
31254 guix system switch-generation 7
31257 The target generation can also be specified relative to the current
31258 generation with the form @code{+N} or @code{-N}, where @code{+3} means
31259 ``3 generations ahead of the current generation,'' and @code{-1} means
31260 ``1 generation prior to the current generation.'' When specifying a
31261 negative value such as @code{-1}, you must precede it with @code{--} to
31262 prevent it from being parsed as an option. For example:
31265 guix system switch-generation -- -1
31268 Currently, the effect of invoking this action is @emph{only} to switch
31269 the system profile to an existing generation and rearrange the
31270 bootloader menu entries. To actually start using the target system
31271 generation, you must reboot after running this action. In the future,
31272 it will be updated to do the same things as @command{reconfigure},
31273 like activating and deactivating services.
31275 This action will fail if the specified generation does not exist.
31278 @cindex rolling back
31279 Switch to the preceding system generation. The next time the system
31280 boots, it will use the preceding system generation. This is the inverse
31281 of @command{reconfigure}, and it is exactly the same as invoking
31282 @command{switch-generation} with an argument of @code{-1}.
31284 Currently, as with @command{switch-generation}, you must reboot after
31285 running this action to actually start using the preceding system
31288 @item delete-generations
31289 @cindex deleting system generations
31290 @cindex saving space
31291 Delete system generations, making them candidates for garbage collection
31292 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
31295 This works in the same way as @samp{guix package --delete-generations}
31296 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
31297 arguments, all system generations but the current one are deleted:
31300 guix system delete-generations
31303 You can also select the generations you want to delete. The example below
31304 deletes all the system generations that are more than two month old:
31307 guix system delete-generations 2m
31310 Running this command automatically reinstalls the bootloader with an updated
31311 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
31312 longer lists the generations that have been deleted.
31315 Build the derivation of the operating system, which includes all the
31316 configuration files and programs needed to boot and run the system.
31317 This action does not actually install anything.
31320 Populate the given directory with all the files necessary to run the
31321 operating system specified in @var{file}. This is useful for first-time
31322 installations of Guix System. For instance:
31325 guix system init my-os-config.scm /mnt
31328 copies to @file{/mnt} all the store items required by the configuration
31329 specified in @file{my-os-config.scm}. This includes configuration
31330 files, packages, and so on. It also creates other essential files
31331 needed for the system to operate correctly---e.g., the @file{/etc},
31332 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
31334 This command also installs bootloader on the target specified in
31335 @file{my-os-config}, unless the @option{--no-bootloader} option was
31339 @cindex virtual machine
31341 @anchor{guix system vm}
31342 Build a virtual machine that contains the operating system declared in
31343 @var{file}, and return a script to run that virtual machine (VM).
31346 The @code{vm} action and others below
31347 can use KVM support in the Linux-libre kernel. Specifically, if the
31348 machine has hardware virtualization support, the corresponding
31349 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
31350 must exist and be readable and writable by the user and by the
31351 build users of the daemon (@pxref{Build Environment Setup}).
31354 Arguments given to the script are passed to QEMU as in the example
31355 below, which enables networking and requests 1@tie{}GiB of RAM for the
31359 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
31362 The VM shares its store with the host system.
31364 Additional file systems can be shared between the host and the VM using
31365 the @option{--share} and @option{--expose} command-line options: the former
31366 specifies a directory to be shared with write access, while the latter
31367 provides read-only access to the shared directory.
31369 The example below creates a VM in which the user's home directory is
31370 accessible read-only, and where the @file{/exchange} directory is a
31371 read-write mapping of @file{$HOME/tmp} on the host:
31374 guix system vm my-config.scm \
31375 --expose=$HOME --share=$HOME/tmp=/exchange
31378 On GNU/Linux, the default is to boot directly to the kernel; this has
31379 the advantage of requiring only a very tiny root disk image since the
31380 store of the host can then be mounted.
31382 The @option{--full-boot} option forces a complete boot sequence, starting
31383 with the bootloader. This requires more disk space since a root image
31384 containing at least the kernel, initrd, and bootloader data files must
31385 be created. The @option{--image-size} option can be used to specify the
31388 @cindex System images, creation in various formats
31389 @cindex Creating system images in various formats
31392 @itemx docker-image
31393 Return a virtual machine, disk image, or Docker image of the operating
31394 system declared in @var{file} that stands alone. By default,
31395 @command{guix system} estimates the size of the image needed to store
31396 the system, but you can use the @option{--image-size} option to specify
31397 a value. Docker images are built to contain exactly what they need, so
31398 the @option{--image-size} option is ignored in the case of
31399 @code{docker-image}.
31401 @cindex disk-image, creating disk images
31402 The @code{disk-image} command can produce various image types. The
31403 image type can be selected using the @option{--image-type} option. It
31404 defaults to @code{raw}. When its value is @code{iso9660}, the
31405 @option{--label} option can be used to specify a volume ID with
31406 @code{disk-image}. By default, the root file system of a disk image is
31407 mounted non-volatile; the @option{--volatile} option can be provided to
31408 make it volatile instead. When using @code{disk-image}, the bootloader
31409 installed on the generated image is taken from the provided
31410 @code{operating-system} definition. The following example demonstrates
31411 how to generate an image that uses the @code{grub-efi-bootloader}
31412 bootloader and boot it with QEMU:
31415 image=$(guix system disk-image --image-type=qcow2 \
31416 gnu/system/examples/lightweight-desktop.tmpl)
31417 cp $image /tmp/my-image.qcow2
31418 chmod +w /tmp/my-image.qcow2
31419 qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
31420 -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
31423 When using the @code{raw} image type, a raw disk image is produced; it
31424 can be copied as is to a USB stick, for instance. Assuming
31425 @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
31426 the image to it using the following command:
31429 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc status=progress
31432 The @code{--list-image-types} command lists all the available image
31435 @cindex vm-image, creating virtual machine images
31436 When using @code{vm-image}, the returned image is in qcow2 format, which
31437 the QEMU emulator can efficiently use. @xref{Running Guix in a VM}, for
31438 more information on how to run the image in a virtual machine. The
31439 @code{grub-bootloader} bootloader is always used independently of what
31440 is declared in the @code{operating-system} file passed as argument.
31441 This is to make it easier to work with QEMU, which uses the SeaBIOS BIOS
31442 by default, expecting a bootloader to be installed in the Master Boot
31445 @cindex docker-image, creating docker images
31446 When using @code{docker-image}, a Docker image is produced. Guix builds
31447 the image from scratch, not from a pre-existing Docker base image. As a
31448 result, it contains @emph{exactly} what you define in the operating
31449 system configuration file. You can then load the image and launch a
31450 Docker container using commands like the following:
31453 image_id="`docker load < guix-system-docker-image.tar.gz`"
31454 container_id="`docker create $image_id`"
31455 docker start $container_id
31458 This command starts a new Docker container from the specified image. It
31459 will boot the Guix system in the usual manner, which means it will
31460 start any services you have defined in the operating system
31461 configuration. You can get an interactive shell running in the container
31462 using @command{docker exec}:
31465 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
31468 Depending on what you run in the Docker container, it
31469 may be necessary to give the container additional permissions. For
31470 example, if you intend to build software using Guix inside of the Docker
31471 container, you may need to pass the @option{--privileged} option to
31472 @code{docker create}.
31474 Last, the @option{--network} option applies to @command{guix system
31475 docker-image}: it produces an image where network is supposedly shared
31476 with the host, and thus without services like nscd or NetworkManager.
31479 Return a script to run the operating system declared in @var{file}
31480 within a container. Containers are a set of lightweight isolation
31481 mechanisms provided by the kernel Linux-libre. Containers are
31482 substantially less resource-demanding than full virtual machines since
31483 the kernel, shared objects, and other resources can be shared with the
31484 host system; this also means they provide thinner isolation.
31486 Currently, the script must be run as root in order to support more than
31487 a single user and group. The container shares its store with the host
31490 As with the @code{vm} action (@pxref{guix system vm}), additional file
31491 systems to be shared between the host and container can be specified
31492 using the @option{--share} and @option{--expose} options:
31495 guix system container my-config.scm \
31496 --expose=$HOME --share=$HOME/tmp=/exchange
31500 This option requires Linux-libre 3.19 or newer.
31505 @var{options} can contain any of the common build options (@pxref{Common
31506 Build Options}). In addition, @var{options} can contain one of the
31510 @item --expression=@var{expr}
31511 @itemx -e @var{expr}
31512 Consider the operating-system @var{expr} evaluates to.
31513 This is an alternative to specifying a file which evaluates to an
31515 This is used to generate the Guix system installer @pxref{Building the
31516 Installation Image}).
31518 @item --system=@var{system}
31519 @itemx -s @var{system}
31520 Attempt to build for @var{system} instead of the host system type.
31521 This works as per @command{guix build} (@pxref{Invoking guix build}).
31525 Return the derivation file name of the given operating system without
31528 @cindex provenance tracking, of the operating system
31529 @item --save-provenance
31530 As discussed above, @command{guix system init} and @command{guix system
31531 reconfigure} always save provenance information @i{via} a dedicated
31532 service (@pxref{Service Reference, @code{provenance-service-type}}).
31533 However, other commands don't do that by default. If you wish to, say,
31534 create a virtual machine image that contains provenance information, you
31538 guix system vm-image --save-provenance config.scm
31541 That way, the resulting image will effectively ``embed its own source''
31542 in the form of meta-data in @file{/run/current-system}. With that
31543 information, one can rebuild the image to make sure it really contains
31544 what it pretends to contain; or they could use that to derive a variant
31547 @item --image-type=@var{type}
31548 @itemx -t @var{type}
31549 For the @code{disk-image} action, create an image with given @var{type}.
31551 When this option is omitted, @command{guix system} uses the @code{raw}
31554 @cindex ISO-9660 format
31555 @cindex CD image format
31556 @cindex DVD image format
31557 @option{--image-type=iso9660} produces an ISO-9660 image, suitable
31558 for burning on CDs and DVDs.
31560 @item --image-size=@var{size}
31561 For the @code{vm-image} and @code{disk-image} actions, create an image
31562 of the given @var{size}. @var{size} may be a number of bytes, or it may
31563 include a unit as a suffix (@pxref{Block size, size specifications,,
31564 coreutils, GNU Coreutils}).
31566 When this option is omitted, @command{guix system} computes an estimate
31567 of the image size as a function of the size of the system declared in
31572 For the @code{container} action, allow containers to access the host network,
31573 that is, do not create a network namespace.
31575 @item --root=@var{file}
31576 @itemx -r @var{file}
31577 Make @var{file} a symlink to the result, and register it as a garbage
31580 @item --skip-checks
31581 Skip pre-installation safety checks.
31583 By default, @command{guix system init} and @command{guix system
31584 reconfigure} perform safety checks: they make sure the file systems that
31585 appear in the @code{operating-system} declaration actually exist
31586 (@pxref{File Systems}), and that any Linux kernel modules that may be
31587 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
31588 RAM Disk}). Passing this option skips these tests altogether.
31590 @item --allow-downgrades
31591 Instruct @command{guix system reconfigure} to allow system downgrades.
31593 By default, @command{reconfigure} prevents you from downgrading your
31594 system. It achieves that by comparing the provenance info of your
31595 system (shown by @command{guix system describe}) with that of your
31596 @command{guix} command (shown by @command{guix describe}). If the
31597 commits for @command{guix} are not descendants of those used for your
31598 system, @command{guix system reconfigure} errors out. Passing
31599 @option{--allow-downgrades} allows you to bypass these checks.
31602 Make sure you understand its security implications before using
31603 @option{--allow-downgrades}.
31607 @cindex on-error strategy
31608 @cindex error strategy
31609 @item --on-error=@var{strategy}
31610 Apply @var{strategy} when an error occurs when reading @var{file}.
31611 @var{strategy} may be one of the following:
31614 @item nothing-special
31615 Report the error concisely and exit. This is the default strategy.
31618 Likewise, but also display a backtrace.
31621 Report the error and enter Guile's debugger. From there, you can run
31622 commands such as @code{,bt} to get a backtrace, @code{,locals} to
31623 display local variable values, and more generally inspect the state of the
31624 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
31625 a list of available debugging commands.
31629 Once you have built, configured, re-configured, and re-re-configured
31630 your Guix installation, you may find it useful to list the operating
31631 system generations available on disk---and that you can choose from the
31632 bootloader boot menu:
31637 Describe the current system generation: its file name, the kernel and
31638 bootloader used, etc., as well as provenance information when available.
31640 @item list-generations
31641 List a summary of each generation of the operating system available on
31642 disk, in a human-readable way. This is similar to the
31643 @option{--list-generations} option of @command{guix package}
31644 (@pxref{Invoking guix package}).
31646 Optionally, one can specify a pattern, with the same syntax that is used
31647 in @command{guix package --list-generations}, to restrict the list of
31648 generations displayed. For instance, the following command displays
31649 generations that are up to 10 days old:
31652 $ guix system list-generations 10d
31657 The @command{guix system} command has even more to offer! The following
31658 sub-commands allow you to visualize how your system services relate to
31661 @anchor{system-extension-graph}
31664 @item extension-graph
31665 Emit to standard output the @dfn{service
31666 extension graph} of the operating system defined in @var{file}
31667 (@pxref{Service Composition}, for more information on service
31668 extensions). By default the output is in Dot/Graphviz format, but you
31669 can choose a different format with @option{--graph-backend}, as with
31670 @command{guix graph} (@pxref{Invoking guix graph, @option{--backend}}):
31675 $ guix system extension-graph @var{file} | xdot -
31678 shows the extension relations among services.
31680 @anchor{system-shepherd-graph}
31681 @item shepherd-graph
31682 Emit to standard output the @dfn{dependency
31683 graph} of shepherd services of the operating system defined in
31684 @var{file}. @xref{Shepherd Services}, for more information and for an
31687 Again, the default output format is Dot/Graphviz, but you can pass
31688 @option{--graph-backend} to select a different one.
31692 @node Invoking guix deploy
31693 @section Invoking @code{guix deploy}
31695 We've already seen @code{operating-system} declarations used to manage a
31696 machine's configuration locally. Suppose you need to configure multiple
31697 machines, though---perhaps you're managing a service on the web that's
31698 comprised of several servers. @command{guix deploy} enables you to use those
31699 same @code{operating-system} declarations to manage multiple remote hosts at
31700 once as a logical ``deployment''.
31703 The functionality described in this section is still under development
31704 and is subject to change. Get in touch with us on
31705 @email{guix-devel@@gnu.org}!
31709 guix deploy @var{file}
31712 Such an invocation will deploy the machines that the code within @var{file}
31713 evaluates to. As an example, @var{file} might contain a definition like this:
31716 ;; This is a Guix deployment of a "bare bones" setup, with
31717 ;; no X11 display server, to a machine with an SSH daemon
31718 ;; listening on localhost:2222. A configuration such as this
31719 ;; may be appropriate for virtual machine with ports
31720 ;; forwarded to the host's loopback interface.
31722 (use-service-modules networking ssh)
31723 (use-package-modules bootloaders)
31727 (host-name "gnu-deployed")
31728 (timezone "Etc/UTC")
31729 (bootloader (bootloader-configuration
31730 (bootloader grub-bootloader)
31731 (target "/dev/vda")
31732 (terminal-outputs '(console))))
31733 (file-systems (cons (file-system
31735 (device "/dev/vda1")
31737 %base-file-systems))
31739 (append (list (service dhcp-client-service-type)
31740 (service openssh-service-type
31741 (openssh-configuration
31742 (permit-root-login #t)
31743 (allow-empty-passwords? #t))))
31747 (operating-system %system)
31748 (environment managed-host-environment-type)
31749 (configuration (machine-ssh-configuration
31750 (host-name "localhost")
31751 (system "x86_64-linux")
31753 (identity "./id_rsa")
31757 The file should evaluate to a list of @var{machine} objects. This example,
31758 upon being deployed, will create a new generation on the remote system
31759 realizing the @code{operating-system} declaration @code{%system}.
31760 @code{environment} and @code{configuration} specify how the machine should be
31761 provisioned---that is, how the computing resources should be created and
31762 managed. The above example does not create any resources, as a
31763 @code{'managed-host} is a machine that is already running the Guix system and
31764 available over the network. This is a particularly simple case; a more
31765 complex deployment may involve, for example, starting virtual machines through
31766 a Virtual Private Server (VPS) provider. In such a case, a different
31767 @var{environment} type would be used.
31769 Do note that you first need to generate a key pair on the coordinator machine
31770 to allow the daemon to export signed archives of files from the store
31771 (@pxref{Invoking guix archive}), though this step is automatic on Guix
31775 # guix archive --generate-key
31779 Each target machine must authorize the key of the master machine so that it
31780 accepts store items it receives from the coordinator:
31783 # guix archive --authorize < coordinator-public-key.txt
31786 @code{user}, in this example, specifies the name of the user account to log in
31787 as to perform the deployment. Its default value is @code{root}, but root
31788 login over SSH may be forbidden in some cases. To work around this,
31789 @command{guix deploy} can log in as an unprivileged user and employ
31790 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
31791 currently installed on the remote and can be invoked non-interactively as
31792 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
31793 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
31794 be accomplished with the following operating system configuration snippet:
31798 (gnu system)) ;for %sudoers-specification
31800 (define %user "username")
31805 (plain-file "sudoers"
31806 (string-append (plain-file-content %sudoers-specification)
31807 (format #f "~a ALL = NOPASSWD: ALL~%"
31812 For more information regarding the format of the @file{sudoers} file,
31813 consult @command{man sudoers}.
31815 @deftp {Data Type} machine
31816 This is the data type representing a single machine in a heterogeneous Guix
31820 @item @code{operating-system}
31821 The object of the operating system configuration to deploy.
31823 @item @code{environment}
31824 An @code{environment-type} describing how the machine should be provisioned.
31826 @item @code{configuration} (default: @code{#f})
31827 An object describing the configuration for the machine's @code{environment}.
31828 If the @code{environment} has a default configuration, @code{#f} may be used.
31829 If @code{#f} is used for an environment with no default configuration,
31830 however, an error will be thrown.
31834 @deftp {Data Type} machine-ssh-configuration
31835 This is the data type representing the SSH client parameters for a machine
31836 with an @code{environment} of @code{managed-host-environment-type}.
31839 @item @code{host-name}
31840 @item @code{build-locally?} (default: @code{#t})
31841 If false, system derivations will be built on the machine being deployed to.
31842 @item @code{system}
31843 The system type describing the architecture of the machine being deployed
31844 to---e.g., @code{"x86_64-linux"}.
31845 @item @code{authorize?} (default: @code{#t})
31846 If true, the coordinator's signing key will be added to the remote's ACL
31848 @item @code{port} (default: @code{22})
31849 @item @code{user} (default: @code{"root"})
31850 @item @code{identity} (default: @code{#f})
31851 If specified, the path to the SSH private key to use to authenticate with the
31854 @item @code{host-key} (default: @code{#f})
31855 This should be the SSH host key of the machine, which looks like this:
31858 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
31861 When @code{host-key} is @code{#f}, the server is authenticated against
31862 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
31865 @item @code{allow-downgrades?} (default: @code{#f})
31866 Whether to allow potential downgrades.
31868 Like @command{guix system reconfigure}, @command{guix deploy} compares
31869 the channel commits currently deployed on the remote host (as returned
31870 by @command{guix system describe}) to those currently in use (as
31871 returned by @command{guix describe}) to determine whether commits
31872 currently in use are descendants of those deployed. When this is not
31873 the case and @code{allow-downgrades?} is false, it raises an error.
31874 This ensures you do not accidentally downgrade remote machines.
31878 @deftp {Data Type} digital-ocean-configuration
31879 This is the data type describing the Droplet that should be created for a
31880 machine with an @code{environment} of @code{digital-ocean-environment-type}.
31883 @item @code{ssh-key}
31884 The path to the SSH private key to use to authenticate with the remote
31885 host. In the future, this field may not exist.
31887 A list of string ``tags'' that uniquely identify the machine. Must be given
31888 such that no two machines in the deployment have the same set of tags.
31889 @item @code{region}
31890 A Digital Ocean region slug, such as @code{"nyc3"}.
31892 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
31893 @item @code{enable-ipv6?}
31894 Whether or not the droplet should be created with IPv6 networking.
31898 @node Running Guix in a VM
31899 @section Running Guix in a Virtual Machine
31901 @cindex virtual machine
31902 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
31904 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
31905 This image is a compressed image in QCOW format. You will first need to
31906 decompress with @command{xz -d}, and then you can pass it to an emulator such
31907 as QEMU (see below for details).
31909 This image boots the Xfce graphical environment and it contains some
31910 commonly used tools. You can install more software in the image by running
31911 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
31912 also reconfigure the system based on its initial configuration file available
31913 as @file{/run/current-system/configuration.scm} (@pxref{Using the
31914 Configuration System}).
31916 Instead of using this pre-built image, one can also build their own virtual
31917 machine image using @command{guix system vm-image} (@pxref{Invoking guix
31918 system}). The returned image is in qcow2 format, which the
31919 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
31922 If you built your own image, you must copy it out of the store
31923 (@pxref{The Store}) and give yourself permission to write to the copy
31924 before you can use it. When invoking QEMU, you must choose a system
31925 emulator that is suitable for your hardware platform. Here is a minimal
31926 QEMU invocation that will boot the result of @command{guix system
31927 vm-image} on x86_64 hardware:
31930 $ qemu-system-x86_64 \
31931 -nic user,model=virtio-net-pci \
31932 -enable-kvm -m 1024 \
31933 -device virtio-blk,drive=myhd \
31934 -drive if=none,file=/tmp/qemu-image,id=myhd
31937 Here is what each of these options means:
31940 @item qemu-system-x86_64
31941 This specifies the hardware platform to emulate. This should match the
31944 @item -nic user,model=virtio-net-pci
31945 Enable the unprivileged user-mode network stack. The guest OS can
31946 access the host but not vice versa. This is the simplest way to get the
31947 guest OS online. @code{model} specifies which network device to emulate:
31948 @code{virtio-net-pci} is a special device made for virtualized operating
31949 systems and recommended for most uses. Assuming your hardware platform is
31950 x86_64, you can get a list of available NIC models by running
31951 @command{qemu-system-x86_64 -nic model=help}.
31954 If your system has hardware virtualization extensions, enabling the
31955 virtual machine support (KVM) of the Linux kernel will make things run
31958 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
31960 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
31961 which may be insufficient for some operations.
31963 @item -device virtio-blk,drive=myhd
31964 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
31965 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
31966 better performance than if it were emulating a complete disk drive. See the
31967 QEMU and KVM documentation for more info.
31969 @item -drive if=none,file=/tmp/qemu-image,id=myhd
31970 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
31971 store of the ``myhd'' drive.
31974 The default @command{run-vm.sh} script that is returned by an invocation of
31975 @command{guix system vm} does not add a @command{-nic user} flag by default.
31976 To get network access from within the vm add the @code{(dhcp-client-service)}
31977 to your system definition and start the VM using
31978 @command{`guix system vm config.scm` -nic user}. An important caveat of using
31979 @command{-nic user} for networking is that @command{ping} will not work, because
31980 it uses the ICMP protocol. You'll have to use a different command to check for
31981 network connectivity, for example @command{guix download}.
31983 @subsection Connecting Through SSH
31987 To enable SSH inside a VM you need to add an SSH server like
31988 @code{openssh-service-type} to your VM (@pxref{Networking Services,
31989 @code{openssh-service-type}}). In addition you need to forward the SSH port,
31990 22 by default, to the host. You can do this with
31993 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
31996 To connect to the VM you can run
31999 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
32002 The @command{-p} tells @command{ssh} the port you want to connect to.
32003 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
32004 every time you modify your @command{config.scm} file and the
32005 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
32006 connection to an unknown host every time you connect.
32008 @subsection Using @command{virt-viewer} with Spice
32010 As an alternative to the default @command{qemu} graphical client you can
32011 use the @command{remote-viewer} from the @command{virt-viewer} package. To
32012 connect pass the @command{-spice port=5930,disable-ticketing} flag to
32013 @command{qemu}. See previous section for further information on how to do this.
32015 Spice also allows you to do some nice stuff like share your clipboard with your
32016 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
32019 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
32020 -chardev spicevmc,name=vdagent,id=vdagent
32021 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
32022 name=com.redhat.spice.0
32025 You'll also need to add the @code{(spice-vdagent-service)} to your
32026 system definition (@pxref{Miscellaneous Services, Spice service}).
32028 @node Defining Services
32029 @section Defining Services
32031 The previous sections show the available services and how one can combine
32032 them in an @code{operating-system} declaration. But how do we define
32033 them in the first place? And what is a service anyway?
32036 * Service Composition:: The model for composing services.
32037 * Service Types and Services:: Types and services.
32038 * Service Reference:: API reference.
32039 * Shepherd Services:: A particular type of service.
32042 @node Service Composition
32043 @subsection Service Composition
32047 Here we define a @dfn{service} as, broadly, something that extends the
32048 functionality of the operating system. Often a service is a process---a
32049 @dfn{daemon}---started when the system boots: a secure shell server, a
32050 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
32051 whose execution can be triggered by another daemon---e.g., an FTP server
32052 started by @command{inetd} or a D-Bus service activated by
32053 @command{dbus-daemon}. Occasionally, a service does not map to a
32054 daemon. For instance, the ``account'' service collects user accounts
32055 and makes sure they exist when the system runs; the ``udev'' service
32056 collects device management rules and makes them available to the eudev
32057 daemon; the @file{/etc} service populates the @file{/etc} directory
32060 @cindex service extensions
32061 Guix system services are connected by @dfn{extensions}. For instance, the
32062 secure shell service @emph{extends} the Shepherd---the
32063 initialization system, running as PID@tie{}1---by giving it the command
32064 lines to start and stop the secure shell daemon (@pxref{Networking
32065 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
32066 service by passing it its @file{.service} specification, and extends the
32067 udev service by passing it device management rules (@pxref{Desktop
32068 Services, @code{upower-service}}); the Guix daemon service extends the
32069 Shepherd by passing it the command lines to start and stop the daemon,
32070 and extends the account service by passing it a list of required build
32071 user accounts (@pxref{Base Services}).
32073 All in all, services and their ``extends'' relations form a directed
32074 acyclic graph (DAG). If we represent services as boxes and extensions
32075 as arrows, a typical system might provide something like this:
32077 @image{images/service-graph,,5in,Typical service extension graph.}
32079 @cindex system service
32080 At the bottom, we see the @dfn{system service}, which produces the
32081 directory containing everything to run and boot the system, as returned
32082 by the @command{guix system build} command. @xref{Service Reference},
32083 to learn about the other service types shown here.
32084 @xref{system-extension-graph, the @command{guix system extension-graph}
32085 command}, for information on how to generate this representation for a
32086 particular operating system definition.
32088 @cindex service types
32089 Technically, developers can define @dfn{service types} to express these
32090 relations. There can be any number of services of a given type on the
32091 system---for instance, a system running two instances of the GNU secure
32092 shell server (lsh) has two instances of @code{lsh-service-type}, with
32093 different parameters.
32095 The following section describes the programming interface for service
32096 types and services.
32098 @node Service Types and Services
32099 @subsection Service Types and Services
32101 A @dfn{service type} is a node in the DAG described above. Let us start
32102 with a simple example, the service type for the Guix build daemon
32103 (@pxref{Invoking guix-daemon}):
32106 (define guix-service-type
32110 (list (service-extension shepherd-root-service-type guix-shepherd-service)
32111 (service-extension account-service-type guix-accounts)
32112 (service-extension activation-service-type guix-activation)))
32113 (default-value (guix-configuration))))
32117 It defines three things:
32121 A name, whose sole purpose is to make inspection and debugging easier.
32124 A list of @dfn{service extensions}, where each extension designates the
32125 target service type and a procedure that, given the parameters of the
32126 service, returns a list of objects to extend the service of that type.
32128 Every service type has at least one service extension. The only
32129 exception is the @dfn{boot service type}, which is the ultimate service.
32132 Optionally, a default value for instances of this type.
32135 In this example, @code{guix-service-type} extends three services:
32138 @item shepherd-root-service-type
32139 The @code{guix-shepherd-service} procedure defines how the Shepherd
32140 service is extended. Namely, it returns a @code{<shepherd-service>}
32141 object that defines how @command{guix-daemon} is started and stopped
32142 (@pxref{Shepherd Services}).
32144 @item account-service-type
32145 This extension for this service is computed by @code{guix-accounts},
32146 which returns a list of @code{user-group} and @code{user-account}
32147 objects representing the build user accounts (@pxref{Invoking
32150 @item activation-service-type
32151 Here @code{guix-activation} is a procedure that returns a gexp, which is
32152 a code snippet to run at ``activation time''---e.g., when the service is
32156 A service of this type is instantiated like this:
32159 (service guix-service-type
32160 (guix-configuration
32162 (extra-options '("--gc-keep-derivations"))))
32165 The second argument to the @code{service} form is a value representing
32166 the parameters of this specific service instance.
32167 @xref{guix-configuration-type, @code{guix-configuration}}, for
32168 information about the @code{guix-configuration} data type. When the
32169 value is omitted, the default value specified by
32170 @code{guix-service-type} is used:
32173 (service guix-service-type)
32176 @code{guix-service-type} is quite simple because it extends other
32177 services but is not extensible itself.
32179 @c @subsubsubsection Extensible Service Types
32181 The service type for an @emph{extensible} service looks like this:
32184 (define udev-service-type
32185 (service-type (name 'udev)
32187 (list (service-extension shepherd-root-service-type
32188 udev-shepherd-service)))
32190 (compose concatenate) ;concatenate the list of rules
32191 (extend (lambda (config rules)
32193 (($ <udev-configuration> udev initial-rules)
32194 (udev-configuration
32195 (udev udev) ;the udev package to use
32196 (rules (append initial-rules rules)))))))))
32199 This is the service type for the
32200 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
32201 management daemon}. Compared to the previous example, in addition to an
32202 extension of @code{shepherd-root-service-type}, we see two new fields:
32206 This is the procedure to @dfn{compose} the list of extensions to
32207 services of this type.
32209 Services can extend the udev service by passing it lists of rules; we
32210 compose those extensions simply by concatenating them.
32213 This procedure defines how the value of the service is @dfn{extended} with
32214 the composition of the extensions.
32216 Udev extensions are composed into a list of rules, but the udev service
32217 value is itself a @code{<udev-configuration>} record. So here, we
32218 extend that record by appending the list of rules it contains to the
32219 list of contributed rules.
32222 This is a string giving an overview of the service type. The string can
32223 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
32224 @command{guix system search} command searches these strings and displays
32225 them (@pxref{Invoking guix system}).
32228 There can be only one instance of an extensible service type such as
32229 @code{udev-service-type}. If there were more, the
32230 @code{service-extension} specifications would be ambiguous.
32232 Still here? The next section provides a reference of the programming
32233 interface for services.
32235 @node Service Reference
32236 @subsection Service Reference
32238 We have seen an overview of service types (@pxref{Service Types and
32239 Services}). This section provides a reference on how to manipulate
32240 services and service types. This interface is provided by the
32241 @code{(gnu services)} module.
32243 @deffn {Scheme Procedure} service @var{type} [@var{value}]
32244 Return a new service of @var{type}, a @code{<service-type>} object (see
32245 below). @var{value} can be any object; it represents the parameters of
32246 this particular service instance.
32248 When @var{value} is omitted, the default value specified by @var{type}
32249 is used; if @var{type} does not specify a default value, an error is
32252 For instance, this:
32255 (service openssh-service-type)
32259 is equivalent to this:
32262 (service openssh-service-type
32263 (openssh-configuration))
32266 In both cases the result is an instance of @code{openssh-service-type}
32267 with the default configuration.
32270 @deffn {Scheme Procedure} service? @var{obj}
32271 Return true if @var{obj} is a service.
32274 @deffn {Scheme Procedure} service-kind @var{service}
32275 Return the type of @var{service}---i.e., a @code{<service-type>} object.
32278 @deffn {Scheme Procedure} service-value @var{service}
32279 Return the value associated with @var{service}. It represents its
32283 Here is an example of how a service is created and manipulated:
32287 (service nginx-service-type
32288 (nginx-configuration
32290 (log-directory log-directory)
32291 (run-directory run-directory)
32292 (file config-file))))
32297 (eq? (service-kind s) nginx-service-type)
32301 The @code{modify-services} form provides a handy way to change the
32302 parameters of some of the services of a list such as
32303 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
32304 evaluates to a list of services. Of course, you could always use
32305 standard list combinators such as @code{map} and @code{fold} to do that
32306 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
32307 @code{modify-services} simply provides a more concise form for this
32310 @deffn {Scheme Syntax} modify-services @var{services} @
32311 (@var{type} @var{variable} => @var{body}) @dots{}
32313 Modify the services listed in @var{services} according to the given
32314 clauses. Each clause has the form:
32317 (@var{type} @var{variable} => @var{body})
32320 where @var{type} is a service type---e.g.,
32321 @code{guix-service-type}---and @var{variable} is an identifier that is
32322 bound within the @var{body} to the service parameters---e.g., a
32323 @code{guix-configuration} instance---of the original service of that
32326 The @var{body} should evaluate to the new service parameters, which will
32327 be used to configure the new service. This new service will replace the
32328 original in the resulting list. Because a service's service parameters
32329 are created using @code{define-record-type*}, you can write a succinct
32330 @var{body} that evaluates to the new service parameters by using the
32331 @code{inherit} feature that @code{define-record-type*} provides.
32333 @xref{Using the Configuration System}, for example usage.
32337 Next comes the programming interface for service types. This is
32338 something you want to know when writing new service definitions, but not
32339 necessarily when simply looking for ways to customize your
32340 @code{operating-system} declaration.
32342 @deftp {Data Type} service-type
32343 @cindex service type
32344 This is the representation of a @dfn{service type} (@pxref{Service Types
32349 This is a symbol, used only to simplify inspection and debugging.
32351 @item @code{extensions}
32352 A non-empty list of @code{<service-extension>} objects (see below).
32354 @item @code{compose} (default: @code{#f})
32355 If this is @code{#f}, then the service type denotes services that cannot
32356 be extended---i.e., services that do not receive ``values'' from other
32359 Otherwise, it must be a one-argument procedure. The procedure is called
32360 by @code{fold-services} and is passed a list of values collected from
32361 extensions. It may return any single value.
32363 @item @code{extend} (default: @code{#f})
32364 If this is @code{#f}, services of this type cannot be extended.
32366 Otherwise, it must be a two-argument procedure: @code{fold-services}
32367 calls it, passing it the initial value of the service as the first
32368 argument and the result of applying @code{compose} to the extension
32369 values as the second argument. It must return a value that is a valid
32370 parameter value for the service instance.
32372 @item @code{description}
32373 This is a string, possibly using Texinfo markup, describing in a couple
32374 of sentences what the service is about. This string allows users to
32375 find about the service through @command{guix system search}
32376 (@pxref{Invoking guix system}).
32378 @item @code{default-value} (default: @code{&no-default-value})
32379 The default value associated for instances of this service type. This
32380 allows users to use the @code{service} form without its second argument:
32383 (service @var{type})
32386 The returned service in this case has the default value specified by
32390 @xref{Service Types and Services}, for examples.
32393 @deffn {Scheme Procedure} service-extension @var{target-type} @
32395 Return a new extension for services of type @var{target-type}.
32396 @var{compute} must be a one-argument procedure: @code{fold-services}
32397 calls it, passing it the value associated with the service that provides
32398 the extension; it must return a valid value for the target service.
32401 @deffn {Scheme Procedure} service-extension? @var{obj}
32402 Return true if @var{obj} is a service extension.
32405 Occasionally, you might want to simply extend an existing service. This
32406 involves creating a new service type and specifying the extension of
32407 interest, which can be verbose; the @code{simple-service} procedure
32408 provides a shorthand for this.
32410 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
32411 Return a service that extends @var{target} with @var{value}. This works
32412 by creating a singleton service type @var{name}, of which the returned
32413 service is an instance.
32415 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
32419 (simple-service 'my-mcron-job mcron-service-type
32420 #~(job '(next-hour (3)) "guix gc -F 2G"))
32424 At the core of the service abstraction lies the @code{fold-services}
32425 procedure, which is responsible for ``compiling'' a list of services
32426 down to a single directory that contains everything needed to boot and
32427 run the system---the directory shown by the @command{guix system build}
32428 command (@pxref{Invoking guix system}). In essence, it propagates
32429 service extensions down the service graph, updating each node parameters
32430 on the way, until it reaches the root node.
32432 @deffn {Scheme Procedure} fold-services @var{services} @
32433 [#:target-type @var{system-service-type}]
32434 Fold @var{services} by propagating their extensions down to the root of
32435 type @var{target-type}; return the root service adjusted accordingly.
32438 Lastly, the @code{(gnu services)} module also defines several essential
32439 service types, some of which are listed below.
32441 @defvr {Scheme Variable} system-service-type
32442 This is the root of the service graph. It produces the system directory
32443 as returned by the @command{guix system build} command.
32446 @defvr {Scheme Variable} boot-service-type
32447 The type of the ``boot service'', which produces the @dfn{boot script}.
32448 The boot script is what the initial RAM disk runs when booting.
32451 @defvr {Scheme Variable} etc-service-type
32452 The type of the @file{/etc} service. This service is used to create
32453 files under @file{/etc} and can be extended by
32454 passing it name/file tuples such as:
32457 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
32460 In this example, the effect would be to add an @file{/etc/issue} file
32461 pointing to the given file.
32464 @defvr {Scheme Variable} setuid-program-service-type
32465 Type for the ``setuid-program service''. This service collects lists of
32466 executable file names, passed as gexps, and adds them to the set of
32467 setuid-root programs on the system (@pxref{Setuid Programs}).
32470 @defvr {Scheme Variable} profile-service-type
32471 Type of the service that populates the @dfn{system profile}---i.e., the
32472 programs under @file{/run/current-system/profile}. Other services can
32473 extend it by passing it lists of packages to add to the system profile.
32476 @cindex provenance tracking, of the operating system
32477 @anchor{provenance-service-type}
32478 @defvr {Scheme Variable} provenance-service-type
32479 This is the type of the service that records @dfn{provenance meta-data}
32480 in the system itself. It creates several files under
32481 @file{/run/current-system}:
32485 This is a ``channel file'' that can be passed to @command{guix pull -C}
32486 or @command{guix time-machine -C}, and which describes the channels used
32487 to build the system, if that information was available
32488 (@pxref{Channels}).
32490 @item configuration.scm
32491 This is the file that was passed as the value for this
32492 @code{provenance-service-type} service. By default, @command{guix
32493 system reconfigure} automatically passes the OS configuration file it
32494 received on the command line.
32497 This contains the same information as the two other files but in a
32498 format that is more readily processable.
32501 In general, these two pieces of information (channels and configuration
32502 file) are enough to reproduce the operating system ``from source''.
32505 This information is necessary to rebuild your operating system, but it
32506 is not always sufficient. In particular, @file{configuration.scm}
32507 itself is insufficient if it is not self-contained---if it refers to
32508 external Guile modules or to extra files. If you want
32509 @file{configuration.scm} to be self-contained, we recommend that modules
32510 or files it refers to be part of a channel.
32512 Besides, provenance meta-data is ``silent'' in the sense that it does
32513 not change the bits contained in your system, @emph{except for the
32514 meta-data bits themselves}. Two different OS configurations or sets of
32515 channels can lead to the same system, bit-for-bit; when
32516 @code{provenance-service-type} is used, these two systems will have
32517 different meta-data and thus different store file names, which makes
32518 comparison less trivial.
32521 This service is automatically added to your operating system
32522 configuration when you use @command{guix system reconfigure},
32523 @command{guix system init}, or @command{guix deploy}.
32526 @node Shepherd Services
32527 @subsection Shepherd Services
32529 @cindex shepherd services
32531 @cindex init system
32532 The @code{(gnu services shepherd)} module provides a way to define
32533 services managed by the GNU@tie{}Shepherd, which is the
32534 initialization system---the first process that is started when the
32535 system boots, also known as PID@tie{}1
32536 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
32538 Services in the Shepherd can depend on each other. For instance, the
32539 SSH daemon may need to be started after the syslog daemon has been
32540 started, which in turn can only happen once all the file systems have
32541 been mounted. The simple operating system defined earlier (@pxref{Using
32542 the Configuration System}) results in a service graph like this:
32544 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
32546 You can actually generate such a graph for any operating system
32547 definition using the @command{guix system shepherd-graph} command
32548 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
32550 The @code{%shepherd-root-service} is a service object representing
32551 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
32552 by passing it lists of @code{<shepherd-service>} objects.
32554 @deftp {Data Type} shepherd-service
32555 The data type representing a service managed by the Shepherd.
32558 @item @code{provision}
32559 This is a list of symbols denoting what the service provides.
32561 These are the names that may be passed to @command{herd start},
32562 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
32563 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
32564 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
32566 @item @code{requirement} (default: @code{'()})
32567 List of symbols denoting the Shepherd services this one depends on.
32569 @cindex one-shot services, for the Shepherd
32570 @item @code{one-shot?} (default: @code{#f})
32571 Whether this service is @dfn{one-shot}. One-shot services stop immediately
32572 after their @code{start} action has completed. @xref{Slots of services,,,
32573 shepherd, The GNU Shepherd Manual}, for more info.
32575 @item @code{respawn?} (default: @code{#t})
32576 Whether to restart the service when it stops, for instance when the
32577 underlying process dies.
32580 @itemx @code{stop} (default: @code{#~(const #f)})
32581 The @code{start} and @code{stop} fields refer to the Shepherd's
32582 facilities to start and stop processes (@pxref{Service De- and
32583 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
32584 G-expressions that get expanded in the Shepherd configuration file
32585 (@pxref{G-Expressions}).
32587 @item @code{actions} (default: @code{'()})
32588 @cindex actions, of Shepherd services
32589 This is a list of @code{shepherd-action} objects (see below) defining
32590 @dfn{actions} supported by the service, in addition to the standard
32591 @code{start} and @code{stop} actions. Actions listed here become available as
32592 @command{herd} sub-commands:
32595 herd @var{action} @var{service} [@var{arguments}@dots{}]
32598 @item @code{auto-start?} (default: @code{#t})
32599 Whether this service should be started automatically by the Shepherd. If it
32600 is @code{#f} the service has to be started manually with @code{herd start}.
32602 @item @code{documentation}
32603 A documentation string, as shown when running:
32606 herd doc @var{service-name}
32609 where @var{service-name} is one of the symbols in @code{provision}
32610 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
32612 @item @code{modules} (default: @code{%default-modules})
32613 This is the list of modules that must be in scope when @code{start} and
32614 @code{stop} are evaluated.
32619 @deftp {Data Type} shepherd-action
32620 This is the data type that defines additional actions implemented by a
32621 Shepherd service (see above).
32625 Symbol naming the action.
32627 @item documentation
32628 This is a documentation string for the action. It can be viewed by running:
32631 herd doc @var{service} action @var{action}
32635 This should be a gexp that evaluates to a procedure of at least one argument,
32636 which is the ``running value'' of the service (@pxref{Slots of services,,,
32637 shepherd, The GNU Shepherd Manual}).
32640 The following example defines an action called @code{say-hello} that kindly
32646 (documentation "Say hi!")
32647 (procedure #~(lambda (running . args)
32648 (format #t "Hello, friend! arguments: ~s\n"
32653 Assuming this action is added to the @code{example} service, then you can do:
32656 # herd say-hello example
32657 Hello, friend! arguments: ()
32658 # herd say-hello example a b c
32659 Hello, friend! arguments: ("a" "b" "c")
32662 This, as you can see, is a fairly sophisticated way to say hello.
32663 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
32667 @defvr {Scheme Variable} shepherd-root-service-type
32668 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
32670 This is the service type that extensions target when they want to create
32671 shepherd services (@pxref{Service Types and Services}, for an example).
32672 Each extension must pass a list of @code{<shepherd-service>}.
32675 @defvr {Scheme Variable} %shepherd-root-service
32676 This service represents PID@tie{}1.
32680 @node Documentation
32681 @chapter Documentation
32683 @cindex documentation, searching for
32684 @cindex searching for documentation
32685 @cindex Info, documentation format
32687 @cindex manual pages
32688 In most cases packages installed with Guix come with documentation.
32689 There are two main documentation formats: ``Info'', a browseable
32690 hypertext format used for GNU software, and ``manual pages'' (or ``man
32691 pages''), the linear documentation format traditionally found on Unix.
32692 Info manuals are accessed with the @command{info} command or with Emacs,
32693 and man pages are accessed using @command{man}.
32695 You can look for documentation of software installed on your system by
32696 keyword. For example, the following command searches for information
32697 about ``TLS'' in Info manuals:
32701 "(emacs)Network Security" -- STARTTLS
32702 "(emacs)Network Security" -- TLS
32703 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
32704 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
32709 The command below searches for the same keyword in man pages:
32713 SSL (7) - OpenSSL SSL/TLS library
32714 certtool (1) - GnuTLS certificate tool
32718 These searches are purely local to your computer so you have the
32719 guarantee that documentation you find corresponds to what you have
32720 actually installed, you can access it off-line, and your privacy is
32723 Once you have these results, you can view the relevant documentation by
32727 $ info "(gnutls)Core TLS API"
32737 Info manuals contain sections and indices as well as hyperlinks like
32738 those found in Web pages. The @command{info} reader (@pxref{Top, Info
32739 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
32740 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
32741 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
32742 Introduction}, for an introduction to Info navigation.
32744 @node Installing Debugging Files
32745 @chapter Installing Debugging Files
32747 @cindex debugging files
32748 Program binaries, as produced by the GCC compilers for instance, are
32749 typically written in the ELF format, with a section containing
32750 @dfn{debugging information}. Debugging information is what allows the
32751 debugger, GDB, to map binary code to source code; it is required to
32752 debug a compiled program in good conditions.
32754 This chapter explains how to use separate debug info when packages
32755 provide it, and how to rebuild packages with debug info when it's
32759 * Separate Debug Info:: Installing 'debug' outputs.
32760 * Rebuilding Debug Info:: Building missing debug info.
32763 @node Separate Debug Info
32764 @section Separate Debug Info
32766 The problem with debugging information is that is takes up a fair amount
32767 of disk space. For example, debugging information for the GNU C Library
32768 weighs in at more than 60 MiB. Thus, as a user, keeping all the
32769 debugging info of all the installed programs is usually not an option.
32770 Yet, space savings should not come at the cost of an impediment to
32771 debugging---especially in the GNU system, which should make it easier
32772 for users to exert their computing freedom (@pxref{GNU Distribution}).
32774 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
32775 mechanism that allows users to get the best of both worlds: debugging
32776 information can be stripped from the binaries and stored in separate
32777 files. GDB is then able to load debugging information from those files,
32778 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
32781 The GNU distribution takes advantage of this by storing debugging
32782 information in the @code{lib/debug} sub-directory of a separate package
32783 output unimaginatively called @code{debug} (@pxref{Packages with
32784 Multiple Outputs}). Users can choose to install the @code{debug} output
32785 of a package when they need it. For instance, the following command
32786 installs the debugging information for the GNU C Library and for GNU
32790 guix install glibc:debug guile:debug
32793 GDB must then be told to look for debug files in the user's profile, by
32794 setting the @code{debug-file-directory} variable (consider setting it
32795 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
32799 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
32802 From there on, GDB will pick up debugging information from the
32803 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
32805 In addition, you will most likely want GDB to be able to show the source
32806 code being debugged. To do that, you will have to unpack the source
32807 code of the package of interest (obtained with @code{guix build
32808 --source}, @pxref{Invoking guix build}), and to point GDB to that source
32809 directory using the @code{directory} command (@pxref{Source Path,
32810 @code{directory},, gdb, Debugging with GDB}).
32812 @c XXX: keep me up-to-date
32813 The @code{debug} output mechanism in Guix is implemented by the
32814 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
32815 opt-in---debugging information is available only for the packages with
32816 definitions explicitly declaring a @code{debug} output. To check
32817 whether a package has a @code{debug} output, use @command{guix package
32818 --list-available} (@pxref{Invoking guix package}).
32820 Read on for how to deal with packages lacking a @code{debug} output.
32822 @node Rebuilding Debug Info
32823 @section Rebuilding Debug Info
32825 @cindex debugging info, rebuilding
32826 As we saw above, some packages, but not all, provide debugging info in a
32827 @code{debug} output. What can you do when debugging info is missing?
32828 The @option{--with-debug-info} option provides a solution to that: it
32829 allows you to rebuild the package(s) for which debugging info is
32830 missing---and only those---and to graft those onto the application
32831 you're debugging. Thus, while it's not as fast as installing a
32832 @code{debug} output, it is relatively inexpensive.
32834 Let's illustrate that. Suppose you're experiencing a bug in Inkscape
32835 and would like to see what's going on in GLib, a library that's deep
32836 down in its dependency graph. As it turns out, GLib does not have a
32837 @code{debug} output and the backtrace GDB shows is all sadness:
32841 #0 0x00007ffff5f92190 in g_getenv ()
32842 from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
32843 #1 0x00007ffff608a7d6 in gobject_init_ctor ()
32844 from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
32845 #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
32846 env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
32847 #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
32851 To address that, you install Inkscape linked against a variant GLib that
32852 contains debug info:
32855 guix install inkscape --with-debug-info=glib
32858 This time, debugging will be a whole lot nicer:
32861 $ gdb --args sh -c 'exec inkscape'
32864 Function "g_getenv" not defined.
32865 Make breakpoint pending on future shared library load? (y or [n]) y
32866 Breakpoint 1 (g_getenv) pending.
32868 Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
32871 #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
32872 #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
32873 #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
32874 #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
32875 env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
32881 Note that there can be packages for which @option{--with-debug-info}
32882 will not have the desired effect. @xref{Package Transformation Options,
32883 @option{--with-debug-info}}, for more information.
32885 @node Security Updates
32886 @chapter Security Updates
32888 @cindex security updates
32889 @cindex security vulnerabilities
32890 Occasionally, important security vulnerabilities are discovered in software
32891 packages and must be patched. Guix developers try hard to keep track of
32892 known vulnerabilities and to apply fixes as soon as possible in the
32893 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
32894 containing only security updates). The @command{guix lint} tool helps
32895 developers find out about vulnerable versions of software packages in the
32900 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
32901 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
32902 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
32906 @xref{Invoking guix lint}, for more information.
32908 Guix follows a functional
32909 package management discipline (@pxref{Introduction}), which implies
32910 that, when a package is changed, @emph{every package that depends on it}
32911 must be rebuilt. This can significantly slow down the deployment of
32912 fixes in core packages such as libc or Bash, since basically the whole
32913 distribution would need to be rebuilt. Using pre-built binaries helps
32914 (@pxref{Substitutes}), but deployment may still take more time than
32918 To address this, Guix implements @dfn{grafts}, a mechanism that allows
32919 for fast deployment of critical updates without the costs associated
32920 with a whole-distribution rebuild. The idea is to rebuild only the
32921 package that needs to be patched, and then to ``graft'' it onto packages
32922 explicitly installed by the user and that were previously referring to
32923 the original package. The cost of grafting is typically very low, and
32924 order of magnitudes lower than a full rebuild of the dependency chain.
32926 @cindex replacements of packages, for grafts
32927 For instance, suppose a security update needs to be applied to Bash.
32928 Guix developers will provide a package definition for the ``fixed''
32929 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
32930 Packages}). Then, the original package definition is augmented with a
32931 @code{replacement} field pointing to the package containing the bug fix:
32938 (replacement bash-fixed)))
32941 From there on, any package depending directly or indirectly on Bash---as
32942 reported by @command{guix gc --requisites} (@pxref{Invoking guix
32943 gc})---that is installed is automatically ``rewritten'' to refer to
32944 @code{bash-fixed} instead of @code{bash}. This grafting process takes
32945 time proportional to the size of the package, usually less than a
32946 minute for an ``average'' package on a recent machine. Grafting is
32947 recursive: when an indirect dependency requires grafting, then grafting
32948 ``propagates'' up to the package that the user is installing.
32950 Currently, the length of the name and version of the graft and that of
32951 the package it replaces (@code{bash-fixed} and @code{bash} in the example
32952 above) must be equal. This restriction mostly comes from the fact that
32953 grafting works by patching files, including binary files, directly.
32954 Other restrictions may apply: for instance, when adding a graft to a
32955 package providing a shared library, the original shared library and its
32956 replacement must have the same @code{SONAME} and be binary-compatible.
32958 The @option{--no-grafts} command-line option allows you to forcefully
32959 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
32963 guix build bash --no-grafts
32967 returns the store file name of the original Bash, whereas:
32974 returns the store file name of the ``fixed'', replacement Bash. This
32975 allows you to distinguish between the two variants of Bash.
32977 To verify which Bash your whole profile refers to, you can run
32978 (@pxref{Invoking guix gc}):
32981 guix gc -R `readlink -f ~/.guix-profile` | grep bash
32985 @dots{} and compare the store file names that you get with those above.
32986 Likewise for a complete Guix system generation:
32989 guix gc -R `guix system build my-config.scm` | grep bash
32992 Lastly, to check which Bash running processes are using, you can use the
32993 @command{lsof} command:
32996 lsof | grep /gnu/store/.*bash
33000 @node Bootstrapping
33001 @chapter Bootstrapping
33003 @c Adapted from the ELS 2013 paper.
33005 @cindex bootstrapping
33007 Bootstrapping in our context refers to how the distribution gets built
33008 ``from nothing''. Remember that the build environment of a derivation
33009 contains nothing but its declared inputs (@pxref{Introduction}). So
33010 there's an obvious chicken-and-egg problem: how does the first package
33011 get built? How does the first compiler get compiled?
33013 It is tempting to think of this question as one that only die-hard
33014 hackers may care about. However, while the answer to that question is
33015 technical in nature, its implications are wide-ranging. How the
33016 distribution is bootstrapped defines the extent to which we, as
33017 individuals and as a collective of users and hackers, can trust the
33018 software we run. It is a central concern from the standpoint of
33019 @emph{security} and from a @emph{user freedom} viewpoint.
33021 @cindex bootstrap binaries
33022 The GNU system is primarily made of C code, with libc at its core. The
33023 GNU build system itself assumes the availability of a Bourne shell and
33024 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
33025 `grep'. Furthermore, build programs---programs that run
33026 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
33027 (@pxref{Derivations}). Consequently, to be able to build anything at
33028 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
33029 Binutils, libc, and the other packages mentioned above---the
33030 @dfn{bootstrap binaries}.
33032 These bootstrap binaries are ``taken for granted'', though we can also
33033 re-create them if needed (@pxref{Preparing to Use the Bootstrap
33037 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
33038 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
33041 @node Reduced Binary Seed Bootstrap
33042 @section The Reduced Binary Seed Bootstrap
33044 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
33045 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
33046 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
33047 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
33048 ``taken for granted.''
33050 Taking the bootstrap binaries for granted means that we consider them to
33051 be a correct and trustworthy ``seed'' for building the complete system.
33052 Therein lies a problem: the combined size of these bootstrap binaries is
33053 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
33054 or even inspecting these is next to impossible.
33056 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
33057 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
33058 Source Bootstrap'' and while we are working towards that goal it would
33059 be hyperbole to use that term for what we do now.}.
33061 The Reduced Binary Seed bootstrap removes the most critical tools---from a
33062 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
33063 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
33064 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
33065 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
33067 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
33068 C Library are built from source. From here on the more traditional
33069 bootstrap process resumes. This approach has reduced the bootstrap
33070 binaries in size to about 145MB in Guix v1.1.
33072 The next step that Guix has taken is to replace the shell and all its
33073 utilities with implementations in Guile Scheme, the @emph{Scheme-only
33074 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
33075 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
33076 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
33077 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
33078 removed are now built from source.
33080 Building the GNU System from source is currently only possibly by adding
33081 some historical GNU packages as intermediate steps@footnote{Packages
33082 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
33083 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
33084 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
33085 and GNU packages become more bootstrappable again (e.g., new releases of
33086 GNU Sed will also ship as gzipped tarballs again, as alternative to the
33087 hard to bootstrap @code{xz}-compression), this set of added packages can
33088 hopefully be reduced again.
33090 The graph below shows the resulting dependency graph for
33091 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
33092 traditional bootstrap of the rest of the Guix System.
33094 @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
33095 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
33097 The only significant binary bootstrap seeds that remain@footnote{
33098 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
33099 together with @code{mes}.} are a Scheme intepreter and a Scheme
33100 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
33101 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
33102 to get Guile running.}.
33104 This further reduction has brought down the size of the binary seed to
33105 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
33107 Work is ongoing to remove all binary blobs from our free software
33108 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
33109 is work to bring these bootstraps to the @code{arm-linux} and
33110 @code{aarch64-linux} architectures and to the Hurd.
33112 If you are interested, join us on @samp{#bootstrappable} on the Freenode
33113 IRC network or discuss on @email{bug-mes@@gnu.org} or
33114 @email{gash-devel@@nongnu.org}.
33116 @node Preparing to Use the Bootstrap Binaries
33117 @section Preparing to Use the Bootstrap Binaries
33119 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
33120 @c large image, it's hard to scroll. Oh well.
33121 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
33123 The figure above shows the very beginning of the dependency graph of the
33124 distribution, corresponding to the package definitions of the @code{(gnu
33125 packages bootstrap)} module. A similar figure can be generated with
33126 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
33129 guix graph -t derivation \
33130 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
33131 | dot -Tps > gcc.ps
33134 or, for the further Reduced Binary Seed bootstrap
33137 guix graph -t derivation \
33138 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
33139 | dot -Tps > mes.ps
33142 At this level of detail, things are
33143 slightly complex. First, Guile itself consists of an ELF executable,
33144 along with many source and compiled Scheme files that are dynamically
33145 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
33146 tarball shown in this graph. This tarball is part of Guix's ``source''
33147 distribution, and gets inserted into the store with @code{add-to-store}
33148 (@pxref{The Store}).
33150 But how do we write a derivation that unpacks this tarball and adds it
33151 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
33152 derivation---the first one that gets built---uses @code{bash} as its
33153 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
33154 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
33155 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
33156 the Guix source distribution, whose sole purpose is to allow the Guile
33157 tarball to be unpacked.
33159 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
33160 Guile that can be used to run subsequent build programs. Its first task
33161 is to download tarballs containing the other pre-built binaries---this
33162 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
33163 @code{ftp-client.scm} are used for this purpose. The
33164 @code{module-import.drv} derivations import those modules in a directory
33165 in the store, using the original layout. The
33166 @code{module-import-compiled.drv} derivations compile those modules, and
33167 write them in an output directory with the right layout. This
33168 corresponds to the @code{#:modules} argument of
33169 @code{build-expression->derivation} (@pxref{Derivations}).
33171 Finally, the various tarballs are unpacked by the derivations
33172 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
33173 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
33174 point we have a working C tool chain.
33176 @unnumberedsec Building the Build Tools
33178 Bootstrapping is complete when we have a full tool chain that does not
33179 depend on the pre-built bootstrap tools discussed above. This
33180 no-dependency requirement is verified by checking whether the files of
33181 the final tool chain contain references to the @file{/gnu/store}
33182 directories of the bootstrap inputs. The process that leads to this
33183 ``final'' tool chain is described by the package definitions found in
33184 the @code{(gnu packages commencement)} module.
33186 The @command{guix graph} command allows us to ``zoom out'' compared to
33187 the graph above, by looking at the level of package objects instead of
33188 individual derivations---remember that a package may translate to
33189 several derivations, typically one derivation to download its source,
33190 one to build the Guile modules it needs, and one to actually build the
33191 package from source. The command:
33194 guix graph -t bag \
33195 -e '(@@@@ (gnu packages commencement)
33196 glibc-final-with-bootstrap-bash)' | xdot -
33200 displays the dependency graph leading to the ``final'' C
33201 library@footnote{You may notice the @code{glibc-intermediate} label,
33202 suggesting that it is not @emph{quite} final, but as a good
33203 approximation, we will consider it final.}, depicted below.
33205 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
33207 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
33208 The first tool that gets built with the bootstrap binaries is
33209 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
33210 for all the following packages. From there Findutils and Diffutils get
33213 Then come the first-stage Binutils and GCC, built as pseudo cross
33214 tools---i.e., with @option{--target} equal to @option{--host}. They are
33215 used to build libc. Thanks to this cross-build trick, this libc is
33216 guaranteed not to hold any reference to the initial tool chain.
33218 From there the final Binutils and GCC (not shown above) are built. GCC
33219 uses @command{ld} from the final Binutils, and links programs against
33220 the just-built libc. This tool chain is used to build the other
33221 packages used by Guix and by the GNU Build System: Guile, Bash,
33224 And voilà! At this point we have the complete set of build tools that
33225 the GNU Build System expects. These are in the @code{%final-inputs}
33226 variable of the @code{(gnu packages commencement)} module, and are
33227 implicitly used by any package that uses @code{gnu-build-system}
33228 (@pxref{Build Systems, @code{gnu-build-system}}).
33231 @unnumberedsec Building the Bootstrap Binaries
33233 @cindex bootstrap binaries
33234 Because the final tool chain does not depend on the bootstrap binaries,
33235 those rarely need to be updated. Nevertheless, it is useful to have an
33236 automated way to produce them, should an update occur, and this is what
33237 the @code{(gnu packages make-bootstrap)} module provides.
33239 The following command builds the tarballs containing the bootstrap binaries
33240 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
33241 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
33242 and Guile, and a tarball containing a mixture of Coreutils and other basic
33243 command-line tools):
33246 guix build bootstrap-tarballs
33249 The generated tarballs are those that should be referred to in the
33250 @code{(gnu packages bootstrap)} module mentioned at the beginning of
33253 Still here? Then perhaps by now you've started to wonder: when do we
33254 reach a fixed point? That is an interesting question! The answer is
33255 unknown, but if you would like to investigate further (and have
33256 significant computational and storage resources to do so), then let us
33259 @unnumberedsec Reducing the Set of Bootstrap Binaries
33261 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
33262 binary code! Why is that a problem? It's a problem because these big chunks
33263 of binary code are practically non-auditable, which makes it hard to establish
33264 what source code produced them. Every unauditable binary also leaves us
33265 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
33266 paper @emph{Reflections on Trusting Trust}.
33268 This is mitigated by the fact that our bootstrap binaries were generated
33269 from an earlier Guix revision. Nevertheless it lacks the level of
33270 transparency that we get in the rest of the package dependency graph,
33271 where Guix always gives us a source-to-binary mapping. Thus, our goal
33272 is to reduce the set of bootstrap binaries to the bare minimum.
33274 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
33275 on-going projects to do that. One of these is about replacing the
33276 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
33277 of increasing complexity, which could be built from source starting from
33278 a simple and auditable assembler.
33280 Our first major achievement is the replacement of of GCC, the GNU C Library
33281 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
33282 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
33283 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
33284 bootstrapped yet and thus we inject them as binary seeds. We call this the
33285 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
33286 binaries! Also, it has eliminated the C compiler binary; i686-linux and
33287 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
33289 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
33290 also looking at any other bootstrap binaries. Your help is welcome!
33293 @chapter Porting to a New Platform
33295 As discussed above, the GNU distribution is self-contained, and
33296 self-containment is achieved by relying on pre-built ``bootstrap
33297 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
33298 operating system kernel, CPU architecture, and application binary
33299 interface (ABI). Thus, to port the distribution to a platform that is
33300 not yet supported, one must build those bootstrap binaries, and update
33301 the @code{(gnu packages bootstrap)} module to use them on that platform.
33303 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
33304 When everything goes well, and assuming the GNU tool chain supports the
33305 target platform, this can be as simple as running a command like this
33309 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
33312 For this to work, the @code{glibc-dynamic-linker} procedure in
33313 @code{(gnu packages bootstrap)} must be augmented to return the right
33314 file name for libc's dynamic linker on that platform; likewise,
33315 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
33316 taught about the new platform.
33318 Once these are built, the @code{(gnu packages bootstrap)} module needs
33319 to be updated to refer to these binaries on the target platform. That
33320 is, the hashes and URLs of the bootstrap tarballs for the new platform
33321 must be added alongside those of the currently supported platforms. The
33322 bootstrap Guile tarball is treated specially: it is expected to be
33323 available locally, and @file{gnu/local.mk} has rules to download it for
33324 the supported architectures; a rule for the new platform must be added
33327 In practice, there may be some complications. First, it may be that the
33328 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
33329 above) is not recognized by all the GNU tools. Typically, glibc
33330 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
33331 configure flag (see @code{gcc.scm} for examples of how to handle this).
33332 Second, some of the required packages could fail to build for that
33333 platform. Lastly, the generated binaries could be broken for some
33336 @c *********************************************************************
33337 @include contributing.texi
33339 @c *********************************************************************
33340 @node Acknowledgments
33341 @chapter Acknowledgments
33343 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
33344 which was designed and
33345 implemented by Eelco Dolstra, with contributions from other people (see
33346 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
33347 management, and promoted unprecedented features, such as transactional
33348 package upgrades and rollbacks, per-user profiles, and referentially
33349 transparent build processes. Without this work, Guix would not exist.
33351 The Nix-based software distributions, Nixpkgs and NixOS, have also been
33352 an inspiration for Guix.
33354 GNU@tie{}Guix itself is a collective work with contributions from a
33355 number of people. See the @file{AUTHORS} file in Guix for more
33356 information on these fine people. The @file{THANKS} file lists people
33357 who have helped by reporting bugs, taking care of the infrastructure,
33358 providing artwork and themes, making suggestions, and more---thank you!
33361 @c *********************************************************************
33362 @node GNU Free Documentation License
33363 @appendix GNU Free Documentation License
33364 @cindex license, GNU Free Documentation License
33365 @include fdl-1.3.texi
33367 @c *********************************************************************
33368 @node Concept Index
33369 @unnumbered Concept Index
33372 @node Programming Index
33373 @unnumbered Programming Index
33374 @syncodeindex tp fn
33375 @syncodeindex vr fn
33380 @c Local Variables:
33381 @c ispell-local-dictionary: "american";