6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
12 @c Identifier of the OpenPGP key used to sign tarballs and such.
13 @set OPENPGP-SIGNING-KEY-ID 27D586A4F8900854329FF09F1260E46482E63562
14 @set OPENPGP-SIGNING-KEY-URL https://sv.gnu.org/people/viewgpg.php?user_id=127547
16 @c Base URL for downloads.
17 @set BASE-URL https://ftp.gnu.org/gnu/guix
19 @c The official substitute server used by default.
20 @set SUBSTITUTE-SERVER-1 ci.guix.gnu.org
21 @set SUBSTITUTE-SERVER-2 bordeaux.guix.gnu.org
22 @set SUBSTITUTE-URLS https://@value{SUBSTITUTE-SERVER-1} https://@value{SUBSTITUTE-SERVER-2}
25 Copyright @copyright{} 2012-2022 Ludovic Courtès@*
26 Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
27 Copyright @copyright{} 2013 Nikita Karetnikov@*
28 Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
29 Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
30 Copyright @copyright{} 2014 Pierre-Antoine Rault@*
31 Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
32 Copyright @copyright{} 2015, 2016, 2017, 2019, 2020, 2021 Leo Famulari@*
33 Copyright @copyright{} 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022 Ricardo Wurmus@*
34 Copyright @copyright{} 2016 Ben Woodcroft@*
35 Copyright @copyright{} 2016, 2017, 2018, 2021 Chris Marusich@*
36 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020, 2021, 2022 Efraim Flashner@*
37 Copyright @copyright{} 2016 John Darrington@*
38 Copyright @copyright{} 2016, 2017 Nikita Gillmann@*
39 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Jan Nieuwenhuizen@*
40 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020, 2021 Julien Lepiller@*
41 Copyright @copyright{} 2016 Alex ter Weele@*
42 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020, 2021 Christopher Baines@*
43 Copyright @copyright{} 2017, 2018, 2019 Clément Lassieur@*
44 Copyright @copyright{} 2017, 2018, 2020, 2021, 2022 Mathieu Othacehe@*
45 Copyright @copyright{} 2017 Federico Beffa@*
46 Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
47 Copyright @copyright{} 2017 Thomas Danckaert@*
48 Copyright @copyright{} 2017 humanitiesNerd@*
49 Copyright @copyright{} 2017, 2021 Christine Lemmer-Webber@*
50 Copyright @copyright{} 2017, 2018, 2019, 2020, 2021, 2022 Marius Bakke@*
51 Copyright @copyright{} 2017, 2019, 2020, 2022 Hartmut Goebel@*
52 Copyright @copyright{} 2017, 2019, 2020, 2021 Maxim Cournoyer@*
53 Copyright @copyright{} 2017–2022 Tobias Geerinckx-Rice@*
54 Copyright @copyright{} 2017 George Clemmer@*
55 Copyright @copyright{} 2017 Andy Wingo@*
56 Copyright @copyright{} 2017, 2018, 2019, 2020 Arun Isaac@*
57 Copyright @copyright{} 2017 nee@*
58 Copyright @copyright{} 2018 Rutger Helling@*
59 Copyright @copyright{} 2018, 2021 Oleg Pykhalov@*
60 Copyright @copyright{} 2018 Mike Gerwitz@*
61 Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
62 Copyright @copyright{} 2018, 2019 Gábor Boskovits@*
63 Copyright @copyright{} 2018, 2019, 2020 Florian Pelz@*
64 Copyright @copyright{} 2018 Laura Lazzati@*
65 Copyright @copyright{} 2018 Alex Vong@*
66 Copyright @copyright{} 2019 Josh Holland@*
67 Copyright @copyright{} 2019, 2020 Diego Nicola Barbato@*
68 Copyright @copyright{} 2019 Ivan Petkov@*
69 Copyright @copyright{} 2019 Jakob L. Kreuze@*
70 Copyright @copyright{} 2019 Kyle Andrews@*
71 Copyright @copyright{} 2019 Alex Griffin@*
72 Copyright @copyright{} 2019, 2020, 2021, 2022 Guillaume Le Vaillant@*
73 Copyright @copyright{} 2020 Liliana Marie Prikler@*
74 Copyright @copyright{} 2019, 2020, 2021, 2022 Simon Tournier@*
75 Copyright @copyright{} 2020 Wiktor Żelazny@*
76 Copyright @copyright{} 2020 Damien Cassou@*
77 Copyright @copyright{} 2020 Jakub Kądziołka@*
78 Copyright @copyright{} 2020 Jack Hill@*
79 Copyright @copyright{} 2020 Naga Malleswari@*
80 Copyright @copyright{} 2020, 2021 Brice Waegeneire@*
81 Copyright @copyright{} 2020 R Veera Kumar@*
82 Copyright @copyright{} 2020, 2021 Pierre Langlois@*
83 Copyright @copyright{} 2020 pinoaffe@*
84 Copyright @copyright{} 2020 André Batista@*
85 Copyright @copyright{} 2020, 2021 Alexandru-Sergiu Marton@*
86 Copyright @copyright{} 2020 raingloom@*
87 Copyright @copyright{} 2020 Daniel Brooks@*
88 Copyright @copyright{} 2020 John Soo@*
89 Copyright @copyright{} 2020 Jonathan Brielmaier@*
90 Copyright @copyright{} 2020 Edgar Vincent@*
91 Copyright @copyright{} 2021, 2022 Maxime Devos@*
92 Copyright @copyright{} 2021 B. Wilson@*
93 Copyright @copyright{} 2021 Xinglu Chen@*
94 Copyright @copyright{} 2021 Raghav Gururajan@*
95 Copyright @copyright{} 2021 Domagoj Stolfa@*
96 Copyright @copyright{} 2021 Hui Lu@*
97 Copyright @copyright{} 2021 pukkamustard@*
98 Copyright @copyright{} 2021 Alice Brenon@*
99 Copyright @copyright{} 2021, 2022 Josselin Poiret@*
100 Copyright @copyright{} 2021 muradm@*
101 Copyright @copyright{} 2021 Andrew Tropin@*
102 Copyright @copyright{} 2021 Sarah Morgensen@*
103 Copyright @copyright{} 2022 Remco van 't Veer@*
104 Copyright @copyright{} 2022 Aleksandr Vityazev@*
105 Copyright @copyright{} 2022 Philip M@sup{c}Grath@*
106 Copyright @copyright{} 2022 Karl Hallsby@*
107 Copyright @copyright{} 2022 Justin Veilleux@*
108 Copyright @copyright{} 2022 Reily Siegel@*
110 Permission is granted to copy, distribute and/or modify this document
111 under the terms of the GNU Free Documentation License, Version 1.3 or
112 any later version published by the Free Software Foundation; with no
113 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
114 copy of the license is included in the section entitled ``GNU Free
115 Documentation License''.
118 @dircategory System administration
120 * Guix: (guix). Manage installed software and system configuration.
121 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
122 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
123 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
124 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
125 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
128 @dircategory Software development
130 * guix shell: (guix)Invoking guix shell. Creating software environments.
131 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
132 * guix build: (guix)Invoking guix build. Building packages.
133 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
137 @title GNU Guix Reference Manual
138 @subtitle Using the GNU Guix Functional Package Manager
139 @author The GNU Guix Developers
142 @vskip 0pt plus 1filll
143 Edition @value{EDITION} @*
151 @c *********************************************************************
155 This document describes GNU Guix version @value{VERSION}, a functional
156 package management tool written for the GNU system.
158 @c TRANSLATORS: You can replace the following paragraph with information on
159 @c how to join your own translation team and how to report issues with the
161 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
162 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
163 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
164 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
165 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
166 would like to translate it in your native language, consider joining
167 @uref{https://translate.fedoraproject.org/projects/guix/documentation-manual,
168 Weblate} (@pxref{Translating Guix}).
171 * Introduction:: What is Guix about?
172 * Installation:: Installing Guix.
173 * System Installation:: Installing the whole operating system.
174 * System Troubleshooting Tips:: When things don't go as planned.
175 * Getting Started:: Your first steps.
176 * Package Management:: Package installation, upgrade, etc.
177 * Channels:: Customizing the package collection.
178 * Development:: Guix-aided software development.
179 * Programming Interface:: Using Guix in Scheme.
180 * Utilities:: Package management commands.
181 * Foreign Architectures:: Build for foreign architectures.
182 * System Configuration:: Configuring the operating system.
183 * Home Configuration:: Configuring the home environment.
184 * Documentation:: Browsing software user manuals.
185 * Installing Debugging Files:: Feeding the debugger.
186 * Using TeX and LaTeX:: Typesetting.
187 * Security Updates:: Deploying security fixes quickly.
188 * Bootstrapping:: GNU/Linux built from scratch.
189 * Porting:: Targeting another platform or kernel.
190 * Contributing:: Your help needed!
192 * Acknowledgments:: Thanks!
193 * GNU Free Documentation License:: The license of this manual.
194 * Concept Index:: Concepts.
195 * Programming Index:: Data types, functions, and variables.
198 --- The Detailed Node Listing ---
202 * Managing Software the Guix Way:: What's special.
203 * GNU Distribution:: The packages and tools.
207 * Binary Installation:: Getting Guix running in no time!
208 * Requirements:: Software needed to build and run Guix.
209 * Running the Test Suite:: Testing Guix.
210 * Setting Up the Daemon:: Preparing the build daemon's environment.
211 * Invoking guix-daemon:: Running the build daemon.
212 * Application Setup:: Application-specific setup.
213 * Upgrading Guix:: Upgrading Guix and its build daemon.
215 Setting Up the Daemon
217 * Build Environment Setup:: Preparing the isolated build environment.
218 * Daemon Offload Setup:: Offloading builds to remote machines.
219 * SELinux Support:: Using an SELinux policy for the daemon.
223 * Limitations:: What you can expect.
224 * Hardware Considerations:: Supported hardware.
225 * USB Stick and DVD Installation:: Preparing the installation medium.
226 * Preparing for Installation:: Networking, partitioning, etc.
227 * Guided Graphical Installation:: Easy graphical installation.
228 * Manual Installation:: Manual installation for wizards.
229 * After System Installation:: When installation succeeded.
230 * Installing Guix in a VM:: Guix System playground.
231 * Building the Installation Image:: How this comes to be.
233 System Troubleshooting Tips
235 * Chrooting into an existing system:: Fixing things from a chroot
239 * Keyboard Layout and Networking and Partitioning:: Initial setup.
240 * Proceeding with the Installation:: Installing.
244 * Features:: How Guix will make your life brighter.
245 * Invoking guix package:: Package installation, removal, etc.
246 * Substitutes:: Downloading pre-built binaries.
247 * Packages with Multiple Outputs:: Single source package, multiple outputs.
248 * Invoking guix gc:: Running the garbage collector.
249 * Invoking guix pull:: Fetching the latest Guix and distribution.
250 * Invoking guix time-machine:: Running an older revision of Guix.
251 * Inferiors:: Interacting with another revision of Guix.
252 * Invoking guix describe:: Display information about your Guix revision.
253 * Invoking guix archive:: Exporting and importing store files.
257 * Official Substitute Servers:: One particular source of substitutes.
258 * Substitute Server Authorization:: How to enable or disable substitutes.
259 * Getting Substitutes from Other Servers:: Substitute diversity.
260 * Substitute Authentication:: How Guix verifies substitutes.
261 * Proxy Settings:: How to get substitutes via proxy.
262 * Substitution Failure:: What happens when substitution fails.
263 * On Trusting Binaries:: How can you trust that binary blob?
267 * Specifying Additional Channels:: Extending the package collection.
268 * Using a Custom Guix Channel:: Using a customized Guix.
269 * Replicating Guix:: Running the @emph{exact same} Guix.
270 * Channel Authentication:: How Guix verifies what it fetches.
271 * Channels with Substitutes:: Using channels with available substitutes.
272 * Creating a Channel:: How to write your custom channel.
273 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
274 * Declaring Channel Dependencies:: How to depend on other channels.
275 * Specifying Channel Authorizations:: Defining channel authors authorizations.
276 * Primary URL:: Distinguishing mirror to original.
277 * Writing Channel News:: Communicating information to channel's users.
281 * Invoking guix shell:: Spawning one-off software environments.
282 * Invoking guix environment:: Setting up development environments.
283 * Invoking guix pack:: Creating software bundles.
284 * The GCC toolchain:: Working with languages supported by GCC.
285 * Invoking guix git authenticate:: Authenticating Git repositories.
287 Programming Interface
289 * Package Modules:: Packages from the programmer's viewpoint.
290 * Defining Packages:: Defining new packages.
291 * Defining Package Variants:: Customizing packages.
292 * Writing Manifests:: The bill of materials of your environment.
293 * Build Systems:: Specifying how packages are built.
294 * Build Phases:: Phases of the build process of a package.
295 * Build Utilities:: Helpers for your package definitions and more.
296 * Search Paths:: Declaring search path environment variables.
297 * The Store:: Manipulating the package store.
298 * Derivations:: Low-level interface to package derivations.
299 * The Store Monad:: Purely functional interface to the store.
300 * G-Expressions:: Manipulating build expressions.
301 * Invoking guix repl:: Programming Guix in Guile.
302 * Using Guix Interactively:: Fine-grain interaction at the REPL.
306 * package Reference:: The package data type.
307 * origin Reference:: The origin data type.
311 * Invoking guix build:: Building packages from the command line.
312 * Invoking guix edit:: Editing package definitions.
313 * Invoking guix download:: Downloading a file and printing its hash.
314 * Invoking guix hash:: Computing the cryptographic hash of a file.
315 * Invoking guix import:: Importing package definitions.
316 * Invoking guix refresh:: Updating package definitions.
317 * Invoking guix style:: Styling package definitions.
318 * Invoking guix lint:: Finding errors in package definitions.
319 * Invoking guix size:: Profiling disk usage.
320 * Invoking guix graph:: Visualizing the graph of packages.
321 * Invoking guix publish:: Sharing substitutes.
322 * Invoking guix challenge:: Challenging substitute servers.
323 * Invoking guix copy:: Copying to and from a remote store.
324 * Invoking guix container:: Process isolation.
325 * Invoking guix weather:: Assessing substitute availability.
326 * Invoking guix processes:: Listing client processes.
328 Invoking @command{guix build}
330 * Common Build Options:: Build options for most commands.
331 * Package Transformation Options:: Creating variants of packages.
332 * Additional Build Options:: Options specific to 'guix build'.
333 * Debugging Build Failures:: Real life packaging experience.
335 Foreign Architectures
336 * Cross-Compilation:: Cross-compiling for another architecture.
337 * Native Builds:: Targeting another architecture through native builds.
341 * Using the Configuration System:: Customizing your GNU system.
342 * operating-system Reference:: Detail of operating-system declarations.
343 * File Systems:: Configuring file system mounts.
344 * Mapped Devices:: Block device extra processing.
345 * Swap Space:: Backing RAM with disk space.
346 * User Accounts:: Specifying user accounts.
347 * Keyboard Layout:: How the system interprets key strokes.
348 * Locales:: Language and cultural convention settings.
349 * Services:: Specifying system services.
350 * Setuid Programs:: Programs running with elevated privileges.
351 * X.509 Certificates:: Authenticating HTTPS servers.
352 * Name Service Switch:: Configuring libc's name service switch.
353 * Initial RAM Disk:: Linux-Libre bootstrapping.
354 * Bootloader Configuration:: Configuring the boot loader.
355 * Invoking guix system:: Instantiating a system configuration.
356 * Invoking guix deploy:: Deploying a system configuration to a remote host.
357 * Running Guix in a VM:: How to run Guix System in a virtual machine.
358 * Defining Services:: Adding new service definitions.
360 Home Environment Configuration
362 * Invoking guix home:: Instantiating a home environment configuration.
366 * Base Services:: Essential system services.
367 * Scheduled Job Execution:: The mcron service.
368 * Log Rotation:: The rottlog service.
369 * Networking Setup:: Setting up network interfaces.
370 * Networking Services:: Firewall, SSH daemon, etc.
371 * Unattended Upgrades:: Automated system upgrades.
372 * X Window:: Graphical display.
373 * Printing Services:: Local and remote printer support.
374 * Desktop Services:: D-Bus and desktop services.
375 * Sound Services:: ALSA and Pulseaudio services.
376 * Database Services:: SQL databases, key-value stores, etc.
377 * Mail Services:: IMAP, POP3, SMTP, and all that.
378 * Messaging Services:: Messaging services.
379 * Telephony Services:: Telephony services.
380 * Monitoring Services:: Monitoring services.
381 * Kerberos Services:: Kerberos services.
382 * LDAP Services:: LDAP services.
383 * Web Services:: Web servers.
384 * Certificate Services:: TLS certificates via Let's Encrypt.
385 * DNS Services:: DNS daemons.
386 * VPN Services:: VPN daemons.
387 * Network File System:: NFS related services.
388 * Continuous Integration:: Cuirass and Laminar services.
389 * Power Management Services:: Extending battery life.
390 * Audio Services:: The MPD.
391 * Virtualization Services:: Virtualization services.
392 * Version Control Services:: Providing remote access to Git repositories.
393 * Game Services:: Game servers.
394 * PAM Mount Service:: Service to mount volumes when logging in.
395 * Guix Services:: Services relating specifically to Guix.
396 * Linux Services:: Services tied to the Linux kernel.
397 * Hurd Services:: Services specific for a Hurd System.
398 * Miscellaneous Services:: Other services.
402 * Service Composition:: The model for composing services.
403 * Service Types and Services:: Types and services.
404 * Service Reference:: API reference.
405 * Shepherd Services:: A particular type of service.
406 * Complex Configurations:: Defining bindings for complex configurations.
408 Installing Debugging Files
410 * Separate Debug Info:: Installing 'debug' outputs.
411 * Rebuilding Debug Info:: Building missing debug info.
415 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
416 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
421 @c *********************************************************************
423 @chapter Introduction
426 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
427 using the international phonetic alphabet (IPA).} is a package
428 management tool for and distribution of the GNU system.
429 Guix makes it easy for unprivileged
430 users to install, upgrade, or remove software packages, to roll back to a
431 previous package set, to build packages from source, and generally
432 assists with the creation and maintenance of software environments.
435 @cindex GuixSD, now Guix System
436 @cindex Guix System Distribution, now Guix System
437 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
438 complements the available tools without interference (@pxref{Installation}),
439 or you can use it as a standalone operating system distribution,
440 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
441 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
442 group everything under the ``Guix'' banner since, after all, Guix System is
443 readily available through the @command{guix system} command, even if you're
444 using a different distro underneath!}. @xref{GNU Distribution}.
447 * Managing Software the Guix Way:: What's special.
448 * GNU Distribution:: The packages and tools.
451 @node Managing Software the Guix Way
452 @section Managing Software the Guix Way
454 @cindex user interfaces
455 Guix provides a command-line package management interface
456 (@pxref{Package Management}), tools to help with software development
457 (@pxref{Development}), command-line utilities for more advanced usage
458 (@pxref{Utilities}), as well as Scheme programming interfaces
459 (@pxref{Programming Interface}).
461 Its @dfn{build daemon} is responsible for building packages on behalf of
462 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
463 binaries from authorized sources (@pxref{Substitutes}).
465 @cindex extensibility of the distribution
466 @cindex customization, of packages
467 Guix includes package definitions for many GNU and non-GNU packages, all
468 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
469 user's computing freedom}. It is @emph{extensible}: users can write
470 their own package definitions (@pxref{Defining Packages}) and make them
471 available as independent package modules (@pxref{Package Modules}). It
472 is also @emph{customizable}: users can @emph{derive} specialized package
473 definitions from existing ones, including from the command line
474 (@pxref{Package Transformation Options}).
476 @cindex functional package management
478 Under the hood, Guix implements the @dfn{functional package management}
479 discipline pioneered by Nix (@pxref{Acknowledgments}).
480 In Guix, the package build and installation process is seen
481 as a @emph{function}, in the mathematical sense. That function takes inputs,
482 such as build scripts, a compiler, and libraries, and
483 returns an installed package. As a pure function, its result depends
484 solely on its inputs---for instance, it cannot refer to software or
485 scripts that were not explicitly passed as inputs. A build function
486 always produces the same result when passed a given set of inputs. It
487 cannot alter the environment of the running system in
488 any way; for instance, it cannot create, modify, or delete files outside
489 of its build and installation directories. This is achieved by running
490 build processes in isolated environments (or @dfn{containers}), where only their
491 explicit inputs are visible.
494 The result of package build functions is @dfn{cached} in the file
495 system, in a special directory called @dfn{the store} (@pxref{The
496 Store}). Each package is installed in a directory of its own in the
497 store---by default under @file{/gnu/store}. The directory name contains
498 a hash of all the inputs used to build that package; thus, changing an
499 input yields a different directory name.
501 This approach is the foundation for the salient features of Guix: support
502 for transactional package upgrade and rollback, per-user installation, and
503 garbage collection of packages (@pxref{Features}).
506 @node GNU Distribution
507 @section GNU Distribution
510 Guix comes with a distribution of the GNU system consisting entirely of
511 free software@footnote{The term ``free'' here refers to the
512 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
513 users of that software}.}. The
514 distribution can be installed on its own (@pxref{System Installation}),
515 but it is also possible to install Guix as a package manager on top of
516 an installed GNU/Linux system (@pxref{Installation}). When we need to
517 distinguish between the two, we refer to the standalone distribution as
520 The distribution provides core GNU packages such as GNU libc, GCC, and
521 Binutils, as well as many GNU and non-GNU applications. The complete
522 list of available packages can be browsed
523 @url{https://www.gnu.org/software/guix/packages,on-line} or by
524 running @command{guix package} (@pxref{Invoking guix package}):
527 guix package --list-available
530 Our goal is to provide a practical 100% free software distribution of
531 Linux-based and other variants of GNU, with a focus on the promotion and
532 tight integration of GNU components, and an emphasis on programs and
533 tools that help users exert that freedom.
535 Packages are currently available on the following platforms:
540 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel.
543 Intel 32-bit architecture (IA32), Linux-Libre kernel.
546 ARMv7-A architecture with hard float, Thumb-2 and NEON,
547 using the EABI hard-float application binary interface (ABI),
548 and Linux-Libre kernel.
551 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
554 @uref{https://hurd.gnu.org, GNU/Hurd} on the Intel 32-bit architecture
557 This configuration is experimental and under development. The easiest
558 way for you to give it a try is by setting up an instance of
559 @code{hurd-vm-service-type} on your GNU/Linux machine
560 (@pxref{transparent-emulation-qemu, @code{hurd-vm-service-type}}).
561 @xref{Contributing}, on how to help!
563 @item mips64el-linux (unsupported)
564 little-endian 64-bit MIPS processors, specifically the Loongson series,
565 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
566 supported; in particular, there is no ongoing work to ensure that this
567 architecture still works. Should someone decide they wish to revive this
568 architecture then the code is still available.
570 @item powerpc-linux (unsupported)
571 big-endian 32-bit PowerPC processors, specifically the PowerPC G4 with
572 AltiVec support, and Linux-Libre kernel. This configuration is not
573 fully supported and there is no ongoing work to ensure this architecture
576 @item powerpc64le-linux
577 little-endian 64-bit Power ISA processors, Linux-Libre kernel. This
578 includes POWER9 systems such as the
579 @uref{https://www.fsf.org/news/talos-ii-mainboard-and-talos-ii-lite-mainboard-now-fsf-certified-to-respect-your-freedom,
580 RYF Talos II mainboard}. This platform is available as a "technology
581 preview": although it is supported, substitutes are not yet available
582 from the build farm (@pxref{Substitutes}), and some packages may fail to
583 build (@pxref{Tracking Bugs and Patches}). That said, the Guix
584 community is actively working on improving this support, and now is a
585 great time to try it and get involved!
588 little-endian 64-bit RISC-V processors, specifically RV64GC, and
589 Linux-Libre kernel. This platform is available as a "technology preview":
590 although it is supported, substitutes are not yet available from the
591 build farm (@pxref{Substitutes}), and some packages may fail to build
592 (@pxref{Tracking Bugs and Patches}). That said, the Guix community is
593 actively working on improving this support, and now is a great time to
594 try it and get involved!
598 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
599 configuration and Guix takes care of instantiating the configuration in a
600 transactional, reproducible, and stateless fashion (@pxref{System
601 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
602 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
603 Manual}), the well-known GNU utilities and tool chain, as well as the
604 graphical environment or system services of your choice.
606 Guix System is available on all the above platforms except
607 @code{mips64el-linux}, @code{powerpc-linux}, @code{powerpc64le-linux} and
608 @code{riscv64-linux}.
611 For information on porting to other architectures or kernels,
614 Building this distribution is a cooperative effort, and you are invited
615 to join! @xref{Contributing}, for information about how you can help.
618 @c *********************************************************************
620 @chapter Installation
622 @cindex installing Guix
625 We recommend the use of this
626 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
627 shell installer script} to install Guix on top of a running GNU/Linux system,
628 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
629 with the installation of the package manager, which can be done on top of a
630 running GNU/Linux system. If, instead, you want to install the complete GNU
631 operating system, @pxref{System Installation}.} The script automates the
632 download, installation, and initial configuration of Guix. It should be run
636 @cindex foreign distro
637 @cindex directories related to foreign distro
638 When installed on a foreign distro, GNU@tie{}Guix complements the available
639 tools without interference. Its data lives exclusively in two directories,
640 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
641 such as @file{/etc}, are left untouched.
643 Once installed, Guix can be updated by running @command{guix pull}
644 (@pxref{Invoking guix pull}).
646 If you prefer to perform the installation steps manually or want to tweak
647 them, you may find the following subsections useful. They describe the
648 software requirements of Guix, as well as how to install it manually and get
652 * Binary Installation:: Getting Guix running in no time!
653 * Requirements:: Software needed to build and run Guix.
654 * Running the Test Suite:: Testing Guix.
655 * Setting Up the Daemon:: Preparing the build daemon's environment.
656 * Invoking guix-daemon:: Running the build daemon.
657 * Application Setup:: Application-specific setup.
658 * Upgrading Guix:: Upgrading Guix and its build daemon.
661 @node Binary Installation
662 @section Binary Installation
664 @cindex installing Guix from binaries
665 @cindex installer script
666 This section describes how to install Guix on an arbitrary system from a
667 self-contained tarball providing binaries for Guix and for all its
668 dependencies. This is often quicker than installing from source, which
669 is described in the next sections. The only requirement is to have
672 @c Note duplicated from the ``Installation'' node.
674 We recommend the use of this
675 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
676 shell installer script}. The script automates the download, installation, and
677 initial configuration steps described below. It should be run as the root
678 user. As root, you can thus run this:
682 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
683 chmod +x guix-install.sh
687 If you're running Debian or a derivative such as Ubuntu, you can instead
688 install the package (it might be a version older than @value{VERSION}
689 but you can update it afterwards by running @samp{guix pull}):
692 sudo apt install guix
695 Likewise on openSUSE:
698 sudo zypper install guix
701 When you're done, @pxref{Application Setup} for extra configuration you
702 might need, and @ref{Getting Started} for your first steps!
705 Installing goes along these lines:
709 @cindex downloading Guix binary
710 Download the binary tarball from
711 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
712 where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
713 @code{i686} (32-bits) machine already running the kernel Linux, and so on
714 (@pxref{GNU Distribution}).
716 @c The following is somewhat duplicated in ``System Installation''.
717 Make sure to download the associated @file{.sig} file and to verify the
718 authenticity of the tarball against it, along these lines:
721 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
722 $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
725 If that command fails because you do not have the required public key,
726 then run this command to import it:
729 $ wget '@value{OPENPGP-SIGNING-KEY-URL}' \
730 -qO - | gpg --import -
734 and rerun the @code{gpg --verify} command.
736 Take note that a warning like ``This key is not certified with a trusted
737 signature!'' is normal.
739 @c end authentication part
742 Now, you need to become the @code{root} user. Depending on your distribution,
743 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
747 # tar --warning=no-timestamp -xf \
748 /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
749 # mv var/guix /var/ && mv gnu /
752 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
753 The latter contains a ready-to-use profile for @code{root} (see next
756 Do @emph{not} unpack the tarball on a working Guix system since that
757 would overwrite its own essential files.
759 The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
760 not emit warnings about ``implausibly old time stamps'' (such
761 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
763 They stem from the fact that all the
764 files in the archive have their modification time set to 1 (which
765 means January 1st, 1970). This is done on purpose to make sure the
766 archive content is independent of its creation time, thus making it
770 Make the profile available under @file{~root/.config/guix/current}, which is
771 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
774 # mkdir -p ~root/.config/guix
775 # ln -sf /var/guix/profiles/per-user/root/current-guix \
776 ~root/.config/guix/current
779 Source @file{etc/profile} to augment @env{PATH} and other relevant
780 environment variables:
783 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
784 source $GUIX_PROFILE/etc/profile
788 Create the group and user accounts for build users as explained below
789 (@pxref{Build Environment Setup}).
792 Run the daemon, and set it to automatically start on boot.
794 If your host distro uses the systemd init system, this can be achieved
797 @c Versions of systemd that supported symlinked service files are not
798 @c yet widely deployed, so we should suggest that users copy the service
801 @c See this thread for more information:
802 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
805 # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
806 ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
808 # systemctl enable --now gnu-store.mount guix-daemon
811 You may also want to arrange for @command{guix gc} to run periodically:
814 # cp ~root/.config/guix/current/lib/systemd/system/guix-gc.service \
815 ~root/.config/guix/current/lib/systemd/system/guix-gc.timer \
817 # systemctl enable --now guix-gc.timer
820 You may want to edit @file{guix-gc.service} to adjust the command line
821 options to fit your needs (@pxref{Invoking guix gc}).
823 If your host distro uses the Upstart init system:
826 # initctl reload-configuration
827 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
832 Otherwise, you can still start the daemon manually with:
835 # ~root/.config/guix/current/bin/guix-daemon \
836 --build-users-group=guixbuild
840 Make the @command{guix} command available to other users on the machine,
844 # mkdir -p /usr/local/bin
846 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
849 It is also a good idea to make the Info version of this manual available
853 # mkdir -p /usr/local/share/info
854 # cd /usr/local/share/info
855 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
859 That way, assuming @file{/usr/local/share/info} is in the search path,
860 running @command{info guix} will open this manual (@pxref{Other Info
861 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
865 @cindex substitutes, authorization thereof
866 To use substitutes from @code{@value{SUBSTITUTE-SERVER-1}},
867 @code{@value{SUBSTITUTE-SERVER-2}} or a mirror (@pxref{Substitutes}),
871 # guix archive --authorize < \
872 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
873 # guix archive --authorize < \
874 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
878 If you do not enable substitutes, Guix will end up building
879 @emph{everything} from source on your machine, making each installation
880 and upgrade very expensive. @xref{On Trusting Binaries}, for a
881 discussion of reasons why one might want do disable substitutes.
885 Each user may need to perform a few additional steps to make their Guix
886 environment ready for use, @pxref{Application Setup}.
889 Voilà, the installation is complete!
891 You can confirm that Guix is working by installing a sample package into
898 The binary installation tarball can be (re)produced and verified simply
899 by running the following command in the Guix source tree:
902 make guix-binary.@var{system}.tar.xz
906 ...@: which, in turn, runs:
909 guix pack -s @var{system} --localstatedir \
910 --profile-name=current-guix guix
913 @xref{Invoking guix pack}, for more info on this handy tool.
916 @section Requirements
918 This section lists requirements when building Guix from source. The
919 build procedure for Guix is the same as for other GNU software, and is
920 not covered here. Please see the files @file{README} and @file{INSTALL}
921 in the Guix source tree for additional details.
923 @cindex official website
924 GNU Guix is available for download from its website at
925 @url{https://www.gnu.org/software/guix/}.
927 GNU Guix depends on the following packages:
930 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x,
931 version 3.0.3 or later;
932 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
935 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
936 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
937 Guile,, gnutls-guile, GnuTLS-Guile});
939 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
941 @item @uref{https://notabug.org/guile-zlib/guile-zlib, Guile-zlib},
942 version 0.1.0 or later;
943 @item @uref{https://notabug.org/guile-lzlib/guile-lzlib, Guile-lzlib};
944 @item @uref{https://www.nongnu.org/guile-avahi/, Guile-Avahi};
946 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, version 0.5.0
948 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON}
950 @item @url{https://www.gnu.org/software/make/, GNU Make}.
953 The following dependencies are optional:
957 @c Note: We need at least 0.13.0 for #:nodelay.
958 Support for build offloading (@pxref{Daemon Offload Setup}) and
959 @command{guix copy} (@pxref{Invoking guix copy}) depends on
960 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
961 version 0.13.0 or later.
964 @uref{https://notabug.org/guile-zstd/guile-zstd, Guile-zstd}, for zstd
965 compression and decompression in @command{guix publish} and for
966 substitutes (@pxref{Invoking guix publish}).
969 @uref{https://ngyro.com/software/guile-semver.html, Guile-Semver} for
970 the @code{crate} importer (@pxref{Invoking guix import}).
973 @uref{https://www.nongnu.org/guile-lib/doc/ref/htmlprag/, Guile-Lib} for
974 the @code{go} importer (@pxref{Invoking guix import}) and for some of
975 the ``updaters'' (@pxref{Invoking guix refresh}).
978 When @url{http://www.bzip.org, libbz2} is available,
979 @command{guix-daemon} can use it to compress build logs.
982 Unless @option{--disable-daemon} was passed to @command{configure}, the
983 following packages are also needed:
986 @item @url{https://gnupg.org/, GNU libgcrypt};
987 @item @url{https://sqlite.org, SQLite 3};
988 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
992 @cindex state directory
993 When configuring Guix on a system that already has a Guix installation,
994 be sure to specify the same state directory as the existing installation
995 using the @option{--localstatedir} option of the @command{configure}
996 script (@pxref{Directory Variables, @code{localstatedir},, standards,
997 GNU Coding Standards}). Usually, this @var{localstatedir} option is
998 set to the value @file{/var}. The @command{configure} script protects
999 against unintended misconfiguration of @var{localstatedir} so you do not
1000 inadvertently corrupt your store (@pxref{The Store}).
1002 @node Running the Test Suite
1003 @section Running the Test Suite
1006 After a successful @command{configure} and @code{make} run, it is a good
1007 idea to run the test suite. It can help catch issues with the setup or
1008 environment, or bugs in Guix itself---and really, reporting test
1009 failures is a good way to help improve the software. To run the test
1016 Test cases can run in parallel: you can use the @code{-j} option of
1017 GNU@tie{}make to speed things up. The first run may take a few minutes
1018 on a recent machine; subsequent runs will be faster because the store
1019 that is created for test purposes will already have various things in
1022 It is also possible to run a subset of the tests by defining the
1023 @code{TESTS} makefile variable as in this example:
1026 make check TESTS="tests/store.scm tests/cpio.scm"
1029 By default, tests results are displayed at a file level. In order to
1030 see the details of every individual test cases, it is possible to define
1031 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
1034 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
1037 The underlying SRFI 64 custom Automake test driver used for the 'check'
1038 test suite (located at @file{build-aux/test-driver.scm}) also allows
1039 selecting which test cases to run at a finer level, via its
1040 @option{--select} and @option{--exclude} options. Here's an example, to
1041 run all the test cases from the @file{tests/packages.scm} test file
1042 whose names start with ``transaction-upgrade-entry'':
1045 export SCM_LOG_DRIVER_FLAGS="--select=^transaction-upgrade-entry"
1046 make check TESTS="tests/packages.scm"
1049 Those wishing to inspect the results of failed tests directly from the
1050 command line can add the @option{--errors-only=yes} option to the
1051 @code{SCM_LOG_DRIVER_FLAGS} makefile variable and set the @code{VERBOSE}
1052 Automake makefile variable, as in:
1055 make check SCM_LOG_DRIVER_FLAGS="--brief=no --errors-only=yes" VERBOSE=1
1058 The @option{--show-duration=yes} option can be used to print the
1059 duration of the individual test cases, when used in combination with
1060 @option{--brief=no}:
1063 make check SCM_LOG_DRIVER_FLAGS="--brief=no --show-duration=yes"
1066 @xref{Parallel Test Harness,,,automake,GNU Automake} for more
1067 information about the Automake Parallel Test Harness.
1069 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
1070 @file{test-suite.log} file. Please specify the Guix version being used
1071 as well as version numbers of the dependencies (@pxref{Requirements}) in
1074 Guix also comes with a whole-system test suite that tests complete
1075 Guix System instances. It can only run on systems where
1076 Guix is already installed, using:
1083 or, again, by defining @code{TESTS} to select a subset of tests to run:
1086 make check-system TESTS="basic mcron"
1089 These system tests are defined in the @code{(gnu tests @dots{})}
1090 modules. They work by running the operating systems under test with
1091 lightweight instrumentation in a virtual machine (VM). They can be
1092 computationally intensive or rather cheap, depending on whether
1093 substitutes are available for their dependencies (@pxref{Substitutes}).
1094 Some of them require a lot of storage space to hold VM images.
1096 Again in case of test failures, please send @email{bug-guix@@gnu.org}
1099 @node Setting Up the Daemon
1100 @section Setting Up the Daemon
1103 Operations such as building a package or running the garbage collector
1104 are all performed by a specialized process, the @dfn{build daemon}, on
1105 behalf of clients. Only the daemon may access the store and its
1106 associated database. Thus, any operation that manipulates the store
1107 goes through the daemon. For instance, command-line tools such as
1108 @command{guix package} and @command{guix build} communicate with the
1109 daemon (@i{via} remote procedure calls) to instruct it what to do.
1111 The following sections explain how to prepare the build daemon's
1112 environment. See also @ref{Substitutes}, for information on how to allow
1113 the daemon to download pre-built binaries.
1116 * Build Environment Setup:: Preparing the isolated build environment.
1117 * Daemon Offload Setup:: Offloading builds to remote machines.
1118 * SELinux Support:: Using an SELinux policy for the daemon.
1121 @node Build Environment Setup
1122 @subsection Build Environment Setup
1124 @cindex build environment
1125 In a standard multi-user setup, Guix and its daemon---the
1126 @command{guix-daemon} program---are installed by the system
1127 administrator; @file{/gnu/store} is owned by @code{root} and
1128 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
1129 Guix tools to build packages or otherwise access the store, and the
1130 daemon will do it on their behalf, ensuring that the store is kept in a
1131 consistent state, and allowing built packages to be shared among users.
1134 When @command{guix-daemon} runs as @code{root}, you may not want package
1135 build processes themselves to run as @code{root} too, for obvious
1136 security reasons. To avoid that, a special pool of @dfn{build users}
1137 should be created for use by build processes started by the daemon.
1138 These build users need not have a shell and a home directory: they will
1139 just be used when the daemon drops @code{root} privileges in build
1140 processes. Having several such users allows the daemon to launch
1141 distinct build processes under separate UIDs, which guarantees that they
1142 do not interfere with each other---an essential feature since builds are
1143 regarded as pure functions (@pxref{Introduction}).
1145 On a GNU/Linux system, a build user pool may be created like this (using
1146 Bash syntax and the @code{shadow} commands):
1148 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
1149 @c for why `-G' is needed.
1151 # groupadd --system guixbuild
1152 # for i in $(seq -w 1 10);
1154 useradd -g guixbuild -G guixbuild \
1155 -d /var/empty -s $(which nologin) \
1156 -c "Guix build user $i" --system \
1162 The number of build users determines how many build jobs may run in
1163 parallel, as specified by the @option{--max-jobs} option
1164 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
1165 @command{guix system vm} and related commands, you may need to add the
1166 build users to the @code{kvm} group so they can access @file{/dev/kvm},
1167 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
1168 (@pxref{Invoking guix system}).
1170 The @code{guix-daemon} program may then be run as @code{root} with the
1171 following command@footnote{If your machine uses the systemd init system,
1172 copying the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
1173 file to @file{/etc/systemd/system} will ensure that
1174 @command{guix-daemon} is automatically started. Similarly, if your
1175 machine uses the Upstart init system, copy the
1176 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
1177 file to @file{/etc/init}.}:
1180 # guix-daemon --build-users-group=guixbuild
1185 This way, the daemon starts build processes in a chroot, under one of
1186 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
1187 environment contains nothing but:
1189 @c Keep this list in sync with libstore/build.cc! -----------------------
1192 a minimal @code{/dev} directory, created mostly independently from the
1193 host @code{/dev}@footnote{``Mostly'', because while the set of files
1194 that appear in the chroot's @code{/dev} is fixed, most of these files
1195 can only be created if the host has them.};
1198 the @code{/proc} directory; it only shows the processes of the container
1199 since a separate PID name space is used;
1202 @file{/etc/passwd} with an entry for the current user and an entry for
1206 @file{/etc/group} with an entry for the user's group;
1209 @file{/etc/hosts} with an entry that maps @code{localhost} to
1213 a writable @file{/tmp} directory.
1216 The chroot does not contain a @file{/home} directory, and the @env{HOME}
1217 environment variable is set to the non-existent
1218 @file{/homeless-shelter}. This helps to highlight inappropriate uses of
1219 @env{HOME} in the build scripts of packages.
1221 You can influence the directory where the daemon stores build trees
1222 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1223 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1224 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1225 This way, the value of @env{TMPDIR} does not leak inside build
1226 environments, which avoids discrepancies in cases where build processes
1227 capture the name of their build tree.
1231 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1232 environment variables for HTTP and HTTPS downloads it performs, be it
1233 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1234 (@pxref{Substitutes}).
1236 If you are installing Guix as an unprivileged user, it is still possible
1237 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1238 However, build processes will not be isolated from one another, and not
1239 from the rest of the system. Thus, build processes may interfere with
1240 each other, and may access programs, libraries, and other files
1241 available on the system---making it much harder to view them as
1242 @emph{pure} functions.
1245 @node Daemon Offload Setup
1246 @subsection Using the Offload Facility
1250 When desired, the build daemon can @dfn{offload} derivation builds to
1251 other machines running Guix, using the @code{offload} @dfn{build
1252 hook}@footnote{This feature is available only when
1253 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1254 present.}. When that feature is enabled, a list of user-specified build
1255 machines is read from @file{/etc/guix/machines.scm}; every time a build
1256 is requested, for instance via @code{guix build}, the daemon attempts to
1257 offload it to one of the machines that satisfy the constraints of the
1258 derivation, in particular its system types---e.g., @code{x86_64-linux}.
1259 A single machine can have multiple system types, either because its
1260 architecture natively supports it, via emulation
1261 (@pxref{transparent-emulation-qemu, Transparent Emulation with QEMU}),
1262 or both. Missing prerequisites for the build are
1263 copied over SSH to the target machine, which then proceeds with the
1264 build; upon success the output(s) of the build are copied back to the
1265 initial machine. The offload facility comes with a basic scheduler that
1266 attempts to select the best machine. The best machine is chosen among
1267 the available machines based on criteria such as:
1271 The availability of a build slot. A build machine can have as many
1272 build slots (connections) as the value of the @code{parallel-builds}
1273 field of its @code{build-machine} object.
1276 Its relative speed, as defined via the @code{speed} field of its
1277 @code{build-machine} object.
1280 Its load. The normalized machine load must be lower than a threshold
1281 value, configurable via the @code{overload-threshold} field of its
1282 @code{build-machine} object.
1285 Disk space availability. More than a 100 MiB must be available.
1288 The @file{/etc/guix/machines.scm} file typically looks like this:
1291 (list (build-machine
1292 (name "eightysix.example.org")
1293 (systems (list "x86_64-linux" "i686-linux"))
1294 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1296 (speed 2.)) ;incredibly fast!
1299 (name "armeight.example.org")
1300 (systems (list "aarch64-linux"))
1301 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1304 ;; Remember 'guix offload' is spawned by
1305 ;; 'guix-daemon' as root.
1306 (private-key "/root/.ssh/identity-for-guix")))
1310 In the example above we specify a list of two build machines, one for
1311 the @code{x86_64} and @code{i686} architectures and one for the
1312 @code{aarch64} architecture.
1314 In fact, this file is---not surprisingly!---a Scheme file that is
1315 evaluated when the @code{offload} hook is started. Its return value
1316 must be a list of @code{build-machine} objects. While this example
1317 shows a fixed list of build machines, one could imagine, say, using
1318 DNS-SD to return a list of potential build machines discovered in the
1319 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1320 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1323 @deftp {Data Type} build-machine
1324 This data type represents build machines to which the daemon may offload
1325 builds. The important fields are:
1330 The host name of the remote machine.
1333 The system types the remote machine supports---e.g., @code{(list
1334 "x86_64-linux" "i686-linux")}.
1337 The user account to use when connecting to the remote machine over SSH.
1338 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1339 allow non-interactive logins.
1342 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1343 This is used to authenticate the machine when we connect to it. It is a
1344 long string that looks like this:
1347 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1350 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1351 key can be found in a file such as
1352 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1354 If the machine is running the SSH daemon of GNU@tie{}lsh,
1355 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1356 similar file. It can be converted to the OpenSSH format using
1357 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1360 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1361 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1366 A number of optional fields may be specified:
1370 @item @code{port} (default: @code{22})
1371 Port number of SSH server on the machine.
1373 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1374 The SSH private key file to use when connecting to the machine, in
1375 OpenSSH format. This key must not be protected with a passphrase.
1377 Note that the default value is the private key @emph{of the root
1378 account}. Make sure it exists if you use the default.
1380 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1381 @itemx @code{compression-level} (default: @code{3})
1382 The SSH-level compression methods and compression level requested.
1384 Note that offloading relies on SSH compression to reduce bandwidth usage
1385 when transferring files to and from build machines.
1387 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1388 File name of the Unix-domain socket @command{guix-daemon} is listening
1391 @item @code{overload-threshold} (default: @code{0.6})
1392 The load threshold above which a potential offload machine is
1393 disregarded by the offload scheduler. The value roughly translates to
1394 the total processor usage of the build machine, ranging from 0.0 (0%) to
1395 1.0 (100%). It can also be disabled by setting
1396 @code{overload-threshold} to @code{#f}.
1398 @item @code{parallel-builds} (default: @code{1})
1399 The number of builds that may run in parallel on the machine.
1401 @item @code{speed} (default: @code{1.0})
1402 A ``relative speed factor''. The offload scheduler will tend to prefer
1403 machines with a higher speed factor.
1405 @item @code{features} (default: @code{'()})
1406 A list of strings denoting specific features supported by the machine.
1407 An example is @code{"kvm"} for machines that have the KVM Linux modules
1408 and corresponding hardware support. Derivations can request features by
1409 name, and they will be scheduled on matching build machines.
1414 The @command{guix} command must be in the search path on the build
1415 machines. You can check whether this is the case by running:
1418 ssh build-machine guix repl --version
1421 There is one last thing to do once @file{machines.scm} is in place. As
1422 explained above, when offloading, files are transferred back and forth
1423 between the machine stores. For this to work, you first need to
1424 generate a key pair on each machine to allow the daemon to export signed
1425 archives of files from the store (@pxref{Invoking guix archive}):
1428 # guix archive --generate-key
1432 Each build machine must authorize the key of the master machine so that
1433 it accepts store items it receives from the master:
1436 # guix archive --authorize < master-public-key.txt
1440 Likewise, the master machine must authorize the key of each build machine.
1442 All the fuss with keys is here to express pairwise mutual trust
1443 relations between the master and the build machines. Concretely, when
1444 the master receives files from a build machine (and @i{vice versa}), its
1445 build daemon can make sure they are genuine, have not been tampered
1446 with, and that they are signed by an authorized key.
1448 @cindex offload test
1449 To test whether your setup is operational, run this command on the
1456 This will attempt to connect to each of the build machines specified in
1457 @file{/etc/guix/machines.scm}, make sure Guix is
1458 available on each machine, attempt to export to the machine and import
1459 from it, and report any error in the process.
1461 If you want to test a different machine file, just specify it on the
1465 # guix offload test machines-qualif.scm
1468 Last, you can test the subset of the machines whose name matches a
1469 regular expression like this:
1472 # guix offload test machines.scm '\.gnu\.org$'
1475 @cindex offload status
1476 To display the current load of all build hosts, run this command on the
1480 # guix offload status
1484 @node SELinux Support
1485 @subsection SELinux Support
1487 @cindex SELinux, daemon policy
1488 @cindex mandatory access control, SELinux
1489 @cindex security, guix-daemon
1490 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1491 can be installed on a system where SELinux is enabled, in order to label
1492 Guix files and to specify the expected behavior of the daemon. Since
1493 Guix System does not provide an SELinux base policy, the daemon policy cannot
1494 be used on Guix System.
1496 @subsubsection Installing the SELinux policy
1497 @cindex SELinux, policy installation
1498 To install the policy run this command as root:
1501 semodule -i etc/guix-daemon.cil
1504 Then relabel the file system with @code{restorecon} or by a different
1505 mechanism provided by your system.
1507 Once the policy is installed, the file system has been relabeled, and
1508 the daemon has been restarted, it should be running in the
1509 @code{guix_daemon_t} context. You can confirm this with the following
1513 ps -Zax | grep guix-daemon
1516 Monitor the SELinux log files as you run a command like @code{guix build
1517 hello} to convince yourself that SELinux permits all necessary
1520 @subsubsection Limitations
1521 @cindex SELinux, limitations
1523 This policy is not perfect. Here is a list of limitations or quirks
1524 that should be considered when deploying the provided SELinux policy for
1529 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1530 operations involve contexts that have anything to do with
1531 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1532 but it would be preferable to define socket rules for only this label.
1535 @code{guix gc} cannot access arbitrary links to profiles. By design,
1536 the file label of the destination of a symlink is independent of the
1537 file label of the link itself. Although all profiles under
1538 $localstatedir are labelled, the links to these profiles inherit the
1539 label of the directory they are in. For links in the user’s home
1540 directory this will be @code{user_home_t}. But for links from the root
1541 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1542 directory, etc, this won’t work. @code{guix gc} would be prevented from
1543 reading and following these links.
1546 The daemon’s feature to listen for TCP connections might no longer work.
1547 This might require extra rules, because SELinux treats network sockets
1548 differently from files.
1551 Currently all files with a name matching the regular expression
1552 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1553 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1554 that name in any profile would be permitted to run in the
1555 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1556 build a package that provides this executable and convince a user to
1557 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1558 At that point SELinux could not prevent it from accessing files that are
1559 allowed for processes in that domain.
1561 You will need to relabel the store directory after all upgrades to
1562 @file{guix-daemon}, such as after running @code{guix pull}. Assuming the
1563 store is in @file{/gnu}, you can do this with @code{restorecon -vR /gnu},
1564 or by other means provided by your operating system.
1566 We could generate a much more restrictive policy at installation time,
1567 so that only the @emph{exact} file name of the currently installed
1568 @code{guix-daemon} executable would be labelled with
1569 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1570 The downside is that root would have to install or upgrade the policy at
1571 installation time whenever the Guix package that provides the
1572 effectively running @code{guix-daemon} executable is upgraded.
1575 @node Invoking guix-daemon
1576 @section Invoking @command{guix-daemon}
1578 The @command{guix-daemon} program implements all the functionality to
1579 access the store. This includes launching build processes, running the
1580 garbage collector, querying the availability of a build result, etc. It
1581 is normally run as @code{root} like this:
1584 # guix-daemon --build-users-group=guixbuild
1587 @cindex socket activation, for @command{guix-daemon}
1588 This daemon can also be started following the systemd ``socket
1589 activation'' protocol (@pxref{Service De- and Constructors,
1590 @code{make-systemd-constructor},, shepherd, The GNU Shepherd Manual}).
1592 For details on how to set it up, @pxref{Setting Up the Daemon}.
1595 @cindex container, build environment
1596 @cindex build environment
1597 @cindex reproducible builds
1598 By default, @command{guix-daemon} launches build processes under
1599 different UIDs, taken from the build group specified with
1600 @option{--build-users-group}. In addition, each build process is run in a
1601 chroot environment that only contains the subset of the store that the
1602 build process depends on, as specified by its derivation
1603 (@pxref{Programming Interface, derivation}), plus a set of specific
1604 system directories. By default, the latter contains @file{/dev} and
1605 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1606 @dfn{container}: in addition to having its own file system tree, it has
1607 a separate mount name space, its own PID name space, network name space,
1608 etc. This helps achieve reproducible builds (@pxref{Features}).
1610 When the daemon performs a build on behalf of the user, it creates a
1611 build directory under @file{/tmp} or under the directory specified by
1612 its @env{TMPDIR} environment variable. This directory is shared with
1613 the container for the duration of the build, though within the container,
1614 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1616 The build directory is automatically deleted upon completion, unless the
1617 build failed and the client specified @option{--keep-failed}
1618 (@pxref{Common Build Options, @option{--keep-failed}}).
1620 The daemon listens for connections and spawns one sub-process for each session
1621 started by a client (one of the @command{guix} sub-commands). The
1622 @command{guix processes} command allows you to get an overview of the activity
1623 on your system by viewing each of the active sessions and clients.
1624 @xref{Invoking guix processes}, for more information.
1626 The following command-line options are supported:
1629 @item --build-users-group=@var{group}
1630 Take users from @var{group} to run build processes (@pxref{Setting Up
1631 the Daemon, build users}).
1633 @item --no-substitutes
1635 Do not use substitutes for build products. That is, always build things
1636 locally instead of allowing downloads of pre-built binaries
1637 (@pxref{Substitutes}).
1639 When the daemon runs with @option{--no-substitutes}, clients can still
1640 explicitly enable substitution @i{via} the @code{set-build-options}
1641 remote procedure call (@pxref{The Store}).
1643 @anchor{daemon-substitute-urls}
1644 @item --substitute-urls=@var{urls}
1645 Consider @var{urls} the default whitespace-separated list of substitute
1646 source URLs. When this option is omitted,
1647 @indicateurl{@value{SUBSTITUTE-URLS}} is used.
1649 This means that substitutes may be downloaded from @var{urls}, as long
1650 as they are signed by a trusted signature (@pxref{Substitutes}).
1652 @xref{Getting Substitutes from Other Servers}, for more information on
1653 how to configure the daemon to get substitutes from other servers.
1657 Do not use offload builds to other machines (@pxref{Daemon Offload
1658 Setup}). That is, always build things locally instead of offloading
1659 builds to remote machines.
1661 @item --cache-failures
1662 Cache build failures. By default, only successful builds are cached.
1664 When this option is used, @command{guix gc --list-failures} can be used
1665 to query the set of store items marked as failed; @command{guix gc
1666 --clear-failures} removes store items from the set of cached failures.
1667 @xref{Invoking guix gc}.
1669 @item --cores=@var{n}
1671 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1674 The default value is @code{0}, but it may be overridden by clients, such
1675 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1678 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1679 in the build process, which can then use it to exploit internal
1680 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1682 @item --max-jobs=@var{n}
1684 Allow at most @var{n} build jobs in parallel. The default value is
1685 @code{1}. Setting it to @code{0} means that no builds will be performed
1686 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1687 Setup}), or simply fail.
1689 @item --max-silent-time=@var{seconds}
1690 When the build or substitution process remains silent for more than
1691 @var{seconds}, terminate it and report a build failure.
1693 The default value is @code{0}, which disables the timeout.
1695 The value specified here can be overridden by clients (@pxref{Common
1696 Build Options, @option{--max-silent-time}}).
1698 @item --timeout=@var{seconds}
1699 Likewise, when the build or substitution process lasts for more than
1700 @var{seconds}, terminate it and report a build failure.
1702 The default value is @code{0}, which disables the timeout.
1704 The value specified here can be overridden by clients (@pxref{Common
1705 Build Options, @option{--timeout}}).
1707 @item --rounds=@var{N}
1708 Build each derivation @var{n} times in a row, and raise an error if
1709 consecutive build results are not bit-for-bit identical. Note that this
1710 setting can be overridden by clients such as @command{guix build}
1711 (@pxref{Invoking guix build}).
1713 When used in conjunction with @option{--keep-failed}, the differing
1714 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1715 This makes it easy to look for differences between the two results.
1718 Produce debugging output.
1720 This is useful to debug daemon start-up issues, but then it may be
1721 overridden by clients, for example the @option{--verbosity} option of
1722 @command{guix build} (@pxref{Invoking guix build}).
1724 @item --chroot-directory=@var{dir}
1725 Add @var{dir} to the build chroot.
1727 Doing this may change the result of build processes---for instance if
1728 they use optional dependencies found in @var{dir} when it is available,
1729 and not otherwise. For that reason, it is not recommended to do so.
1730 Instead, make sure that each derivation declares all the inputs that it
1733 @item --disable-chroot
1734 Disable chroot builds.
1736 Using this option is not recommended since, again, it would allow build
1737 processes to gain access to undeclared dependencies. It is necessary,
1738 though, when @command{guix-daemon} is running under an unprivileged user
1741 @item --log-compression=@var{type}
1742 Compress build logs according to @var{type}, one of @code{gzip},
1743 @code{bzip2}, or @code{none}.
1745 Unless @option{--lose-logs} is used, all the build logs are kept in the
1746 @var{localstatedir}. To save space, the daemon automatically compresses
1747 them with gzip by default.
1749 @item --discover[=yes|no]
1750 Whether to discover substitute servers on the local network using mDNS
1753 This feature is still experimental. However, here are a few
1758 It might be faster/less expensive than fetching from remote servers;
1760 There are no security risks, only genuine substitutes will be used
1761 (@pxref{Substitute Authentication});
1763 An attacker advertising @command{guix publish} on your LAN cannot serve
1764 you malicious binaries, but they can learn what software you’re
1767 Servers may serve substitute over HTTP, unencrypted, so anyone on the
1768 LAN can see what software you’re installing.
1771 It is also possible to enable or disable substitute server discovery at
1772 run-time by running:
1775 herd discover guix-daemon on
1776 herd discover guix-daemon off
1779 @item --disable-deduplication
1780 @cindex deduplication
1781 Disable automatic file ``deduplication'' in the store.
1783 By default, files added to the store are automatically ``deduplicated'':
1784 if a newly added file is identical to another one found in the store,
1785 the daemon makes the new file a hard link to the other file. This can
1786 noticeably reduce disk usage, at the expense of slightly increased
1787 input/output load at the end of a build process. This option disables
1790 @item --gc-keep-outputs[=yes|no]
1791 Tell whether the garbage collector (GC) must keep outputs of live
1795 @cindex garbage collector roots
1796 When set to @code{yes}, the GC will keep the outputs of any live
1797 derivation available in the store---the @file{.drv} files. The default
1798 is @code{no}, meaning that derivation outputs are kept only if they are
1799 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1802 @item --gc-keep-derivations[=yes|no]
1803 Tell whether the garbage collector (GC) must keep derivations
1804 corresponding to live outputs.
1806 When set to @code{yes}, as is the case by default, the GC keeps
1807 derivations---i.e., @file{.drv} files---as long as at least one of their
1808 outputs is live. This allows users to keep track of the origins of
1809 items in their store. Setting it to @code{no} saves a bit of disk
1812 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1813 liveness to flow from outputs to derivations, and setting
1814 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1815 derivations to outputs. When both are set to @code{yes}, the effect is
1816 to keep all the build prerequisites (the sources, compiler, libraries,
1817 and other build-time tools) of live objects in the store, regardless of
1818 whether these prerequisites are reachable from a GC root. This is
1819 convenient for developers since it saves rebuilds or downloads.
1821 @item --impersonate-linux-2.6
1822 On Linux-based systems, impersonate Linux 2.6. This means that the
1823 kernel's @command{uname} system call will report 2.6 as the release number.
1825 This might be helpful to build programs that (usually wrongfully) depend
1826 on the kernel version number.
1829 Do not keep build logs. By default they are kept under
1830 @file{@var{localstatedir}/guix/log}.
1832 @item --system=@var{system}
1833 Assume @var{system} as the current system type. By default it is the
1834 architecture/kernel pair found at configure time, such as
1835 @code{x86_64-linux}.
1837 @item --listen=@var{endpoint}
1838 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1839 as the file name of a Unix-domain socket if it starts with
1840 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1841 host name or host name and port to listen to. Here are a few examples:
1844 @item --listen=/gnu/var/daemon
1845 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1846 creating it if needed.
1848 @item --listen=localhost
1849 @cindex daemon, remote access
1850 @cindex remote access to the daemon
1851 @cindex daemon, cluster setup
1852 @cindex clusters, daemon setup
1853 Listen for TCP connections on the network interface corresponding to
1854 @code{localhost}, on port 44146.
1856 @item --listen=128.0.0.42:1234
1857 Listen for TCP connections on the network interface corresponding to
1858 @code{128.0.0.42}, on port 1234.
1861 This option can be repeated multiple times, in which case
1862 @command{guix-daemon} accepts connections on all the specified
1863 endpoints. Users can tell client commands what endpoint to connect to
1864 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1865 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1868 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1869 @option{--listen=@var{host}} is suitable on local networks, such as
1870 clusters, where only trusted nodes may connect to the build daemon. In
1871 other cases where remote access to the daemon is needed, we recommend
1872 using Unix-domain sockets along with SSH.
1875 When @option{--listen} is omitted, @command{guix-daemon} listens for
1876 connections on the Unix-domain socket located at
1877 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1881 @node Application Setup
1882 @section Application Setup
1884 @cindex foreign distro
1885 When using Guix on top of GNU/Linux distribution other than Guix System---a
1886 so-called @dfn{foreign distro}---a few additional steps are needed to
1887 get everything in place. Here are some of them.
1891 @anchor{locales-and-locpath}
1892 @cindex locales, when not on Guix System
1894 @vindex GUIX_LOCPATH
1895 Packages installed @i{via} Guix will not use the locale data of the
1896 host system. Instead, you must first install one of the locale packages
1897 available with Guix and then define the @env{GUIX_LOCPATH} environment
1901 $ guix install glibc-locales
1902 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1905 Note that the @code{glibc-locales} package contains data for all the
1906 locales supported by the GNU@tie{}libc and weighs in at around
1907 930@tie{}MiB@footnote{The size of the @code{glibc-locales} package is
1908 reduced down to about 213@tie{}MiB with store deduplication and further
1909 down to about 67@tie{}MiB when using a zstd-compressed Btrfs file
1910 system.}. If you only need a few locales, you can define your custom
1911 locales package via the @code{make-glibc-utf8-locales} procedure from
1912 the @code{(gnu packages base)} module. The following example defines a
1913 package containing the various Canadian UTF-8 locales known to the
1914 GNU@tie{}libc, that weighs around 14@tie{}MiB:
1917 (use-modules (gnu packages base))
1919 (define my-glibc-locales
1920 (make-glibc-utf8-locales
1922 #:locales (list "en_CA" "fr_CA" "ik_CA" "iu_CA" "shs_CA")
1923 #:name "glibc-canadian-utf8-locales"))
1926 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1927 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1928 Manual}). There are two important differences though:
1932 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1933 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1934 to make sure the programs of the foreign distro will not end up loading
1935 incompatible locale data.
1938 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1939 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1940 should your Guix profile contain a mixture of programs linked against
1941 different libc version, each libc version will only try to load locale
1942 data in the right format.
1945 This is important because the locale data format used by different libc
1946 versions may be incompatible.
1948 @subsection Name Service Switch
1950 @cindex name service switch, glibc
1951 @cindex NSS (name service switch), glibc
1952 @cindex nscd (name service caching daemon)
1953 @cindex name service caching daemon (nscd)
1954 When using Guix on a foreign distro, we @emph{strongly recommend} that
1955 the system run the GNU C library's @dfn{name service cache daemon},
1956 @command{nscd}, which should be listening on the
1957 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1958 installed with Guix may fail to look up host names or user accounts, or
1959 may even crash. The next paragraphs explain why.
1961 @cindex @file{nsswitch.conf}
1962 The GNU C library implements a @dfn{name service switch} (NSS), which is
1963 an extensible mechanism for ``name lookups'' in general: host name
1964 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1965 The GNU C Library Reference Manual}).
1967 @cindex Network information service (NIS)
1968 @cindex NIS (Network information service)
1969 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1970 lookup implementations: for example, the @code{nss-mdns} plugin allow
1971 resolution of @code{.local} host names, the @code{nis} plugin allows
1972 user account lookup using the Network information service (NIS), and so
1973 on. These extra ``lookup services'' are configured system-wide in
1974 @file{/etc/nsswitch.conf}, and all the programs running on the system
1975 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1978 When they perform a name lookup---for instance by calling the
1979 @code{getaddrinfo} function in C---applications first try to connect to
1980 the nscd; on success, nscd performs name lookups on their behalf. If
1981 the nscd is not running, then they perform the name lookup by
1982 themselves, by loading the name lookup services into their own address
1983 space and running it. These name lookup services---the
1984 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1985 the host system's C library, rather than from the C library the
1986 application is linked against (the C library coming from Guix).
1988 And this is where the problem is: if your application is linked against
1989 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1990 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1991 likely crash or have its name lookups fail unexpectedly.
1993 Running @command{nscd} on the system, among other advantages, eliminates
1994 this binary incompatibility problem because those @code{libnss_*.so}
1995 files are loaded in the @command{nscd} process, not in applications
1998 @subsection X11 Fonts
2001 The majority of graphical applications use Fontconfig to locate and load
2002 fonts and perform X11-client-side rendering. The @code{fontconfig}
2003 package in Guix looks for fonts in @file{$HOME/.guix-profile} by
2004 default. Thus, to allow graphical applications installed with Guix to
2005 display fonts, you have to install fonts with Guix as well. Essential
2006 font packages include @code{font-ghostscript}, @code{font-dejavu}, and
2007 @code{font-gnu-freefont}.
2009 @cindex @code{fc-cache}
2011 Once you have installed or removed fonts, or when you notice an
2012 application that does not find fonts, you may need to install Fontconfig
2013 and to force an update of its font cache by running:
2016 guix install fontconfig
2020 To display text written in Chinese languages, Japanese, or Korean in
2021 graphical applications, consider installing
2022 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
2023 has multiple outputs, one per language family (@pxref{Packages with
2024 Multiple Outputs}). For instance, the following command installs fonts
2025 for Chinese languages:
2028 guix install font-adobe-source-han-sans:cn
2031 @cindex @code{xterm}
2032 Older programs such as @command{xterm} do not use Fontconfig and instead
2033 rely on server-side font rendering. Such programs require to specify a
2034 full name of a font using XLFD (X Logical Font Description), like this:
2037 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
2040 To be able to use such full names for the TrueType fonts installed in
2041 your Guix profile, you need to extend the font path of the X server:
2043 @c Note: 'xset' does not accept symlinks so the trick below arranges to
2044 @c get at the real directory. See <https://bugs.gnu.org/30655>.
2046 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
2049 @cindex @code{xlsfonts}
2050 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
2051 to make sure your TrueType fonts are listed there.
2054 @subsection X.509 Certificates
2056 @cindex @code{nss-certs}
2057 The @code{nss-certs} package provides X.509 certificates, which allow
2058 programs to authenticate Web servers accessed over HTTPS.
2060 When using Guix on a foreign distro, you can install this package and
2061 define the relevant environment variables so that packages know where to
2062 look for certificates. @xref{X.509 Certificates}, for detailed
2065 @subsection Emacs Packages
2067 @cindex @code{emacs}
2068 When you install Emacs packages with Guix, the Elisp files are placed
2069 under the @file{share/emacs/site-lisp/} directory of the profile in
2070 which they are installed. The Elisp libraries are made available to
2071 Emacs through the @env{EMACSLOADPATH} environment variable, which is
2072 set when installing Emacs itself.
2074 Additionally, autoload definitions are automatically evaluated at the
2075 initialization of Emacs, by the Guix-specific
2076 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
2077 want to avoid auto-loading the Emacs packages installed with Guix, you
2078 can do so by running Emacs with the @option{--no-site-file} option
2079 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
2082 @node Upgrading Guix
2083 @section Upgrading Guix
2085 @cindex Upgrading Guix, on a foreign distro
2087 To upgrade Guix, run:
2093 @xref{Invoking guix pull}, for more information.
2095 @cindex upgrading Guix for the root user, on a foreign distro
2096 @cindex upgrading the Guix daemon, on a foreign distro
2097 @cindex @command{guix pull} for the root user, on a foreign distro
2099 On a foreign distro, you can upgrade the build daemon by running:
2106 followed by (assuming your distro uses the systemd service management
2110 systemctl restart guix-daemon.service
2113 On Guix System, upgrading the daemon is achieved by reconfiguring the
2114 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
2118 @c *********************************************************************
2119 @node System Installation
2120 @chapter System Installation
2122 @cindex installing Guix System
2123 @cindex Guix System, installation
2124 This section explains how to install Guix System
2125 on a machine. Guix, as a package manager, can
2126 also be installed on top of a running GNU/Linux system,
2127 @pxref{Installation}.
2131 @c This paragraph is for people reading this from tty2 of the
2132 @c installation image.
2133 You are reading this documentation with an Info reader. For details on
2134 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
2135 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
2136 Info}. Hit @kbd{l} afterwards to come back here.
2138 Alternatively, run @command{info info} in another tty to keep the manual
2144 * Limitations:: What you can expect.
2145 * Hardware Considerations:: Supported hardware.
2146 * USB Stick and DVD Installation:: Preparing the installation medium.
2147 * Preparing for Installation:: Networking, partitioning, etc.
2148 * Guided Graphical Installation:: Easy graphical installation.
2149 * Manual Installation:: Manual installation for wizards.
2150 * After System Installation:: When installation succeeded.
2151 * Installing Guix in a VM:: Guix System playground.
2152 * Building the Installation Image:: How this comes to be.
2156 @section Limitations
2158 We consider Guix System to be ready for a wide range of ``desktop'' and server
2159 use cases. The reliability guarantees it provides---transactional upgrades
2160 and rollbacks, reproducibility---make it a solid foundation.
2162 Nevertheless, before you proceed with the installation, be aware of the
2163 following noteworthy limitations applicable to version @value{VERSION}:
2167 More and more system services are provided (@pxref{Services}), but some
2171 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
2172 as well as a number of X11 window managers. However, KDE is currently
2176 More than a disclaimer, this is an invitation to report issues (and success
2177 stories!), and to join us in improving it. @xref{Contributing}, for more
2181 @node Hardware Considerations
2182 @section Hardware Considerations
2184 @cindex hardware support on Guix System
2185 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
2186 builds around the kernel Linux-libre, which means that only hardware for
2187 which free software drivers and firmware exist is supported. Nowadays,
2188 a wide range of off-the-shelf hardware is supported on
2189 GNU/Linux-libre---from keyboards to graphics cards to scanners and
2190 Ethernet controllers. Unfortunately, there are still areas where
2191 hardware vendors deny users control over their own computing, and such
2192 hardware is not supported on Guix System.
2194 @cindex WiFi, hardware support
2195 One of the main areas where free drivers or firmware are lacking is WiFi
2196 devices. WiFi devices known to work include those using Atheros chips
2197 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
2198 driver, and those using Broadcom/AirForce chips (BCM43xx with
2199 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
2200 Linux-libre driver. Free firmware exists for both and is available
2201 out-of-the-box on Guix System, as part of @code{%base-firmware}
2202 (@pxref{operating-system Reference, @code{firmware}}).
2204 @cindex RYF, Respects Your Freedom
2205 The @uref{https://www.fsf.org/, Free Software Foundation} runs
2206 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
2207 certification program for hardware products that respect your freedom
2208 and your privacy and ensure that you have control over your device. We
2209 encourage you to check the list of RYF-certified devices.
2211 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
2212 web site. It contains a catalog of hardware devices with information
2213 about their support in GNU/Linux.
2216 @node USB Stick and DVD Installation
2217 @section USB Stick and DVD Installation
2219 An ISO-9660 installation image that can be written to a USB stick or
2220 burnt to a DVD can be downloaded from
2221 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso},
2222 where you can replace @code{x86_64-linux} with one of:
2226 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
2229 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
2232 @c start duplication of authentication part from ``Binary Installation''
2233 Make sure to download the associated @file{.sig} file and to verify the
2234 authenticity of the image against it, along these lines:
2237 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
2238 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
2241 If that command fails because you do not have the required public key,
2242 then run this command to import it:
2245 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
2246 -qO - | gpg --import -
2250 and rerun the @code{gpg --verify} command.
2252 Take note that a warning like ``This key is not certified with a trusted
2253 signature!'' is normal.
2257 This image contains the tools necessary for an installation.
2258 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
2260 @unnumberedsubsec Copying to a USB Stick
2262 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
2263 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
2264 copy the image with:
2267 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX status=progress
2271 Access to @file{/dev/sdX} usually requires root privileges.
2273 @unnumberedsubsec Burning on a DVD
2275 Insert a blank DVD into your machine, and determine
2276 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
2277 copy the image with:
2280 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
2283 Access to @file{/dev/srX} usually requires root privileges.
2285 @unnumberedsubsec Booting
2287 Once this is done, you should be able to reboot the system and boot from
2288 the USB stick or DVD@. The latter usually requires you to get in the
2289 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2290 In order to boot from Libreboot, switch to the command mode by pressing
2291 the @kbd{c} key and type @command{search_grub usb}.
2293 @xref{Installing Guix in a VM}, if, instead, you would like to install
2294 Guix System in a virtual machine (VM).
2297 @node Preparing for Installation
2298 @section Preparing for Installation
2300 Once you have booted, you can use the guided graphical installer, which makes
2301 it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
2302 if you are already familiar with GNU/Linux and if you want more control than
2303 what the graphical installer provides, you can choose the ``manual''
2304 installation process (@pxref{Manual Installation}).
2306 The graphical installer is available on TTY1. You can obtain root shells on
2307 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2308 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2309 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2310 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2311 which allows you to select text with the left mouse button and to paste it
2312 with the middle button.
2315 Installation requires access to the Internet so that any missing
2316 dependencies of your system configuration can be downloaded. See the
2317 ``Networking'' section below.
2320 @node Guided Graphical Installation
2321 @section Guided Graphical Installation
2323 The graphical installer is a text-based user interface. It will guide you,
2324 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2326 The first dialog boxes allow you to set up the system as you use it during the
2327 installation: you can choose the language, keyboard layout, and set up
2328 networking, which will be used during the installation. The image below shows
2329 the networking dialog.
2331 @image{images/installer-network,5in,, networking setup with the graphical installer}
2333 Later steps allow you to partition your hard disk, as shown in the image
2334 below, to choose whether or not to use encrypted file systems, to enter the
2335 host name and root password, and to create an additional account, among other
2338 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2340 Note that, at any time, the installer allows you to exit the current
2341 installation step and resume at a previous step, as show in the image below.
2343 @image{images/installer-resume,5in,, resuming the installation process}
2345 Once you're done, the installer produces an operating system configuration and
2346 displays it (@pxref{Using the Configuration System}). At that point you can
2347 hit ``OK'' and installation will proceed. On success, you can reboot into the
2348 new system and enjoy. @xref{After System Installation}, for what's next!
2351 @node Manual Installation
2352 @section Manual Installation
2354 This section describes how you would ``manually'' install GNU@tie{}Guix System
2355 on your machine. This option requires familiarity with GNU/Linux, with the
2356 shell, and with common administration tools. If you think this is not for
2357 you, consider using the guided graphical installer (@pxref{Guided Graphical
2360 The installation system provides root shells on TTYs 3 to 6; press
2361 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2362 many common tools needed to install the system, but is also a full-blown
2363 Guix System. This means that you can install additional packages, should you
2364 need it, using @command{guix package} (@pxref{Invoking guix package}).
2367 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2368 * Proceeding with the Installation:: Installing.
2371 @node Keyboard Layout and Networking and Partitioning
2372 @subsection Keyboard Layout, Networking, and Partitioning
2374 Before you can install the system, you may want to adjust the keyboard layout,
2375 set up networking, and partition your target hard disk. This section will
2376 guide you through this.
2378 @subsubsection Keyboard Layout
2380 @cindex keyboard layout
2381 The installation image uses the US qwerty keyboard layout. If you want
2382 to change it, you can use the @command{loadkeys} command. For example,
2383 the following command selects the Dvorak keyboard layout:
2389 See the files under @file{/run/current-system/profile/share/keymaps} for
2390 a list of available keyboard layouts. Run @command{man loadkeys} for
2393 @anchor{manual-installation-networking}
2394 @subsubsection Networking
2396 Run the following command to see what your network interfaces are called:
2403 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2409 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2410 Wired interfaces have a name starting with @samp{e}; for example, the
2411 interface corresponding to the first on-board Ethernet controller is
2412 called @samp{eno1}. Wireless interfaces have a name starting with
2413 @samp{w}, like @samp{w1p2s0}.
2416 @item Wired connection
2417 To configure a wired network run the following command, substituting
2418 @var{interface} with the name of the wired interface you want to use.
2421 ifconfig @var{interface} up
2425 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2428 ip link set @var{interface} up
2431 @item Wireless connection
2434 To configure wireless networking, you can create a configuration file
2435 for the @command{wpa_supplicant} configuration tool (its location is not
2436 important) using one of the available text editors such as
2440 nano wpa_supplicant.conf
2443 As an example, the following stanza can go to this file and will work
2444 for many wireless networks, provided you give the actual SSID and
2445 passphrase for the network you are connecting to:
2449 ssid="@var{my-ssid}"
2451 psk="the network's secret passphrase"
2455 Start the wireless service and run it in the background with the
2456 following command (substitute @var{interface} with the name of the
2457 network interface you want to use):
2460 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2463 Run @command{man wpa_supplicant} for more information.
2467 At this point, you need to acquire an IP address. On a network where IP
2468 addresses are automatically assigned @i{via} DHCP, you can run:
2471 dhclient -v @var{interface}
2474 Try to ping a server to see if networking is up and running:
2480 Setting up network access is almost always a requirement because the
2481 image does not contain all the software and tools that may be needed.
2483 @cindex proxy, during system installation
2484 If you need HTTP and HTTPS access to go through a proxy, run the
2488 herd set-http-proxy guix-daemon @var{URL}
2492 where @var{URL} is the proxy URL, for example
2493 @code{http://example.org:8118}.
2495 @cindex installing over SSH
2496 If you want to, you can continue the installation remotely by starting
2500 herd start ssh-daemon
2503 Make sure to either set a password with @command{passwd}, or configure
2504 OpenSSH public key authentication before logging in.
2506 @subsubsection Disk Partitioning
2508 Unless this has already been done, the next step is to partition, and
2509 then format the target partition(s).
2511 The installation image includes several partitioning tools, including
2512 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2513 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2514 the partition layout you want:
2520 If your disk uses the GUID Partition Table (GPT) format and you plan to
2521 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2522 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2525 @cindex EFI, installation
2526 @cindex UEFI, installation
2527 @cindex ESP, EFI system partition
2528 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2529 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2530 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2533 parted /dev/sda set 1 esp on
2537 @vindex grub-bootloader
2538 @vindex grub-efi-bootloader
2539 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2540 @file{/sys/firmware/efi} exists in the installation image, then you should
2541 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2542 Otherwise you should use the BIOS-based GRUB, known as
2543 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2547 Once you are done partitioning the target hard disk drive, you have to
2548 create a file system on the relevant partition(s)@footnote{Currently
2549 Guix System only supports ext4, btrfs, JFS, F2FS, and XFS file systems. In
2550 particular, code that reads file system UUIDs and labels only works for these
2551 file system types.}. For the ESP, if you have one and assuming it is
2552 @file{/dev/sda1}, run:
2555 mkfs.fat -F32 /dev/sda1
2558 For the root file system, ext4 is the most widely used format. Other
2559 file systems, such as Btrfs, support compression, which is reported to
2560 nicely complement file deduplication that the daemon performs
2561 independently of the file system (@pxref{Invoking guix-daemon,
2564 Preferably, assign file systems a label so that you can easily and
2565 reliably refer to them in @code{file-system} declarations (@pxref{File
2566 Systems}). This is typically done using the @code{-L} option of
2567 @command{mkfs.ext4} and related commands. So, assuming the target root
2568 partition lives at @file{/dev/sda2}, a file system with the label
2569 @code{my-root} can be created with:
2572 mkfs.ext4 -L my-root /dev/sda2
2575 @cindex encrypted disk
2576 If you are instead planning to encrypt the root partition, you can use
2577 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2578 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2579 @code{man cryptsetup}} for more information).
2582 Note that GRUB can unlock LUKS2 devices since version 2.06, but only
2583 supports the PBKDF2 key derivation function, which is not the default
2584 for @command{cryptsetup luksFormat}. You can check which key derivation
2585 function is being used by a device by running @command{cryptsetup
2586 luksDump @var{device}}, and looking for the PBKDF field of your
2590 Assuming you want to store the root partition on @file{/dev/sda2}, the
2591 command sequence to format it as a LUKS2 partition would be along these
2595 cryptsetup luksFormat --type luks2 --pbkdf pbkdf2 /dev/sda2
2596 cryptsetup open /dev/sda2 my-partition
2597 mkfs.ext4 -L my-root /dev/mapper/my-partition
2600 Once that is done, mount the target file system under @file{/mnt}
2601 with a command like (again, assuming @code{my-root} is the label of the
2605 mount LABEL=my-root /mnt
2608 Also mount any other file systems you would like to use on the target
2609 system relative to this path. If you have opted for @file{/boot/efi} as an
2610 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2611 found by @code{guix system init} afterwards.
2613 Finally, if you plan to use one or more swap partitions (@pxref{Swap
2614 Space}), make sure to initialize them with @command{mkswap}. Assuming
2615 you have one swap partition on @file{/dev/sda3}, you would run:
2622 Alternatively, you may use a swap file. For example, assuming that in
2623 the new system you want to use the file @file{/swapfile} as a swap file,
2624 you would run@footnote{This example will work for many types of file
2625 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2626 btrfs), the required steps may be different. For details, see the
2627 manual pages for @command{mkswap} and @command{swapon}.}:
2630 # This is 10 GiB of swap space. Adjust "count" to change the size.
2631 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2632 # For security, make the file readable and writable only by root.
2633 chmod 600 /mnt/swapfile
2634 mkswap /mnt/swapfile
2635 swapon /mnt/swapfile
2638 Note that if you have encrypted the root partition and created a swap
2639 file in its file system as described above, then the encryption also
2640 protects the swap file, just like any other file in that file system.
2642 @node Proceeding with the Installation
2643 @subsection Proceeding with the Installation
2645 With the target partitions ready and the target root mounted on
2646 @file{/mnt}, we're ready to go. First, run:
2649 herd start cow-store /mnt
2652 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2653 during the installation phase are written to the target disk on @file{/mnt}
2654 rather than kept in memory. This is necessary because the first phase of
2655 the @command{guix system init} command (see below) entails downloads or
2656 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2658 Next, you have to edit a file and
2659 provide the declaration of the operating system to be installed. To
2660 that end, the installation system comes with three text editors. We
2661 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2662 supports syntax highlighting and parentheses matching; other editors
2663 include mg (an Emacs clone), and
2664 nvi (a clone of the original BSD @command{vi} editor).
2665 We strongly recommend storing that file on the target root file system, say,
2666 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2667 configuration file once you have rebooted into the newly-installed system.
2669 @xref{Using the Configuration System}, for an overview of the
2670 configuration file. The example configurations discussed in that
2671 section are available under @file{/etc/configuration} in the
2672 installation image. Thus, to get started with a system configuration
2673 providing a graphical display server (a ``desktop'' system), you can run
2674 something along these lines:
2678 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2679 # nano /mnt/etc/config.scm
2682 You should pay attention to what your configuration file contains, and
2687 Make sure the @code{bootloader-configuration} form refers to the targets
2688 you want to install GRUB on. It should mention @code{grub-bootloader}
2689 if you are installing GRUB in the legacy way, or
2690 @code{grub-efi-bootloader} for newer UEFI systems. For legacy systems,
2691 the @code{targets} field contain the names of the devices, like
2692 @code{(list "/dev/sda")}; for UEFI systems it names the paths to mounted
2693 EFI partitions, like @code{(list "/boot/efi")}; do make sure the paths
2694 are currently mounted and a @code{file-system} entry is specified in
2698 Be sure that your file system labels match the value of their respective
2699 @code{device} fields in your @code{file-system} configuration, assuming
2700 your @code{file-system} configuration uses the @code{file-system-label}
2701 procedure in its @code{device} field.
2704 If there are encrypted or RAID partitions, make sure to add a
2705 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2708 Once you are done preparing the configuration file, the new system must
2709 be initialized (remember that the target root file system is mounted
2713 guix system init /mnt/etc/config.scm /mnt
2717 This copies all the necessary files and installs GRUB on
2718 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2719 more information, @pxref{Invoking guix system}. This command may trigger
2720 downloads or builds of missing packages, which can take some time.
2722 Once that command has completed---and hopefully succeeded!---you can run
2723 @command{reboot} and boot into the new system. The @code{root} password
2724 in the new system is initially empty; other users' passwords need to be
2725 initialized by running the @command{passwd} command as @code{root},
2726 unless your configuration specifies otherwise
2727 (@pxref{user-account-password, user account passwords}).
2728 @xref{After System Installation}, for what's next!
2731 @node After System Installation
2732 @section After System Installation
2734 Success, you've now booted into Guix System! From then on, you can update the
2735 system whenever you want by running, say:
2739 sudo guix system reconfigure /etc/config.scm
2743 This builds a new system generation with the latest packages and services
2744 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2745 your system includes the latest security updates (@pxref{Security Updates}).
2747 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2749 @cindex sudo vs. @command{guix pull}
2750 Note that @command{sudo guix} runs your user's @command{guix} command and
2751 @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
2752 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2754 The difference matters here, because @command{guix pull} updates
2755 the @command{guix} command and package definitions only for the user it is run
2756 as. This means that if you choose to use @command{guix system reconfigure} in
2757 root's login shell, you'll need to @command{guix pull} separately.
2760 Now, @pxref{Getting Started}, and
2761 join us on @code{#guix} on the Libera Chat IRC network or on
2762 @email{guix-devel@@gnu.org} to share your experience!
2765 @node Installing Guix in a VM
2766 @section Installing Guix in a Virtual Machine
2768 @cindex virtual machine, Guix System installation
2769 @cindex virtual private server (VPS)
2770 @cindex VPS (virtual private server)
2771 If you'd like to install Guix System in a virtual machine (VM) or on a
2772 virtual private server (VPS) rather than on your beloved machine, this
2775 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2776 disk image, follow these steps:
2780 First, retrieve and decompress the Guix system installation image as
2781 described previously (@pxref{USB Stick and DVD Installation}).
2784 Create a disk image that will hold the installed system. To make a
2785 qcow2-formatted disk image, use the @command{qemu-img} command:
2788 qemu-img create -f qcow2 guix-system.img 50G
2791 The resulting file will be much smaller than 50 GB (typically less than
2792 1 MB), but it will grow as the virtualized storage device is filled up.
2795 Boot the USB installation image in an VM:
2798 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2799 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2800 -drive file=guix-system.img \
2801 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2804 @code{-enable-kvm} is optional, but significantly improves performance,
2805 @pxref{Running Guix in a VM}.
2808 You're now root in the VM, proceed with the installation process.
2809 @xref{Preparing for Installation}, and follow the instructions.
2812 Once installation is complete, you can boot the system that's on your
2813 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2816 @node Building the Installation Image
2817 @section Building the Installation Image
2819 @cindex installation image
2820 The installation image described above was built using the @command{guix
2821 system} command, specifically:
2824 guix system image -t iso9660 gnu/system/install.scm
2827 Have a look at @file{gnu/system/install.scm} in the source tree,
2828 and see also @ref{Invoking guix system} for more information
2829 about the installation image.
2831 @section Building the Installation Image for ARM Boards
2833 Many ARM boards require a specific variant of the
2834 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2836 If you build a disk image and the bootloader is not available otherwise
2837 (on another boot drive etc), it's advisable to build an image that
2838 includes the bootloader, specifically:
2841 guix system image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2844 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2845 board, a list of possible boards will be printed.
2847 @c *********************************************************************
2848 @cindex troubleshooting, guix system
2849 @cindex guix system troubleshooting
2850 @node System Troubleshooting Tips
2851 @chapter System Troubleshooting Tips
2853 Guix System allows rebooting into a previous generation should the last
2854 one be malfunctioning, which makes it quite robust against being broken
2855 irreversibly. This feature depends on GRUB being correctly functioning
2856 though, which means that if for whatever reasons your GRUB installation
2857 becomes corrupted during a system reconfiguration, you may not be able
2858 to easily boot into a previous generation. A technique that can be used
2859 in this case is to @i{chroot} into your broken system and reconfigure it
2860 from there. Such technique is explained below.
2862 @cindex chroot, guix system
2863 @cindex chrooting, guix system
2864 @cindex repairing GRUB, via chroot
2865 @node Chrooting into an existing system
2866 @section Chrooting into an existing system
2868 This section details how to @i{chroot} to an already installed Guix
2869 System with the aim of reconfiguring it, for example to fix a broken
2870 GRUB installation. The process is similar to how it would be done on
2871 other GNU/Linux systems, but there are some Guix System particularities
2872 such as the daemon and profiles that make it worthy of explaining here.
2876 Obtain a bootable image of Guix System. It is recommended the latest
2877 development snapshot so the kernel and the tools used are at least as as
2878 new as those of your installed system; it can be retrieved from the
2879 @url{https://ci.guix.gnu.org/search/latest/ISO-9660?query=spec:images+status:success+system:x86_64-linux+image.iso,
2880 https://ci.guix.gnu.org} URL. Follow the @pxref{USB Stick and DVD
2881 Installation} section for copying it to a bootable media.
2884 Boot the image, and proceed with the graphical text-based installer
2885 until your network is configured. Alternatively, you could configure
2886 the network manually by following the
2887 @ref{manual-installation-networking} section. If you get the error
2888 @samp{RTNETLINK answers: Operation not possible due to RF-kill}, try
2889 @samp{rfkill list} followed by @samp{rfkill unblock 0}, where @samp{0}
2890 is your device identifier (ID).
2893 Switch to a virtual console (tty) if you haven't already by pressing
2894 simultaneously the @kbd{Control + Alt + F4} keys. Mount your file
2895 system at @file{/mnt}. Assuming your root partition is
2896 @file{/dev/sda2}, you would do:
2899 mount /dev/sda2 /mnt
2903 Mount special block devices and Linux-specific directories:
2906 mount --bind /proc /mnt/proc
2907 mount --bind /sys /mnt/sys
2908 mount --bind /dev /mnt/dev
2911 If your system is EFI-based, you must also mount the ESP partition.
2912 Assuming it is @file{/dev/sda1}, you can do so with:
2915 mount /dev/sda1 /mnt/boot/efi
2919 Enter your system via chroot:
2926 Source your @var{user} profile to setup the environment, where
2927 @var{user} is the user name used for the Guix System you are attempting
2931 source /home/@var{user}/.guix-profile/etc/profile
2934 To ensure you are working with the Guix revision you normally would as
2935 your normal user, also source your current Guix profile:
2938 source /home/@var{user}/.config/guix/current/etc/profile
2942 Start a minimal @command{guix-daemon} in the background:
2945 guix-daemon --build-users-group=guixbuild --disable-chroot &
2949 Edit your Guix System configuration if needed, then reconfigure with:
2952 guix system reconfigure your-config.scm
2956 Finally, you should be good to reboot the system to test your fix.
2960 @c *********************************************************************
2961 @node Getting Started
2962 @chapter Getting Started
2964 Presumably, you've reached this section because either you have
2965 installed Guix on top of another distribution (@pxref{Installation}), or
2966 you've installed the standalone Guix System (@pxref{System
2967 Installation}). It's time for you to get started using Guix and this
2968 section aims to help you do that and give you a feel of what it's like.
2970 Guix is about installing software, so probably the first thing you'll
2971 want to do is to actually look for software. Let's say you're looking
2972 for a text editor, you can run:
2975 guix search text editor
2978 This command shows you a number of matching @dfn{packages}, each time
2979 showing the package's name, version, a description, and additional info.
2980 Once you've found out the one you want to use, let's say Emacs (ah ha!),
2981 you can go ahead and install it (run this command as a regular user,
2982 @emph{no need for root privileges}!):
2989 You've installed your first package, congrats! The package is now
2990 visible in your default @dfn{profile}, @file{$HOME/.guix-profile}---a
2991 profile is a directory containing installed packages.
2992 In the process, you've
2993 probably noticed that Guix downloaded pre-built binaries; or, if you
2994 explicitly chose to @emph{not} use pre-built binaries, then probably
2995 Guix is still building software (@pxref{Substitutes}, for more info).
2997 Unless you're using Guix System, the @command{guix install} command must
2998 have printed this hint:
3001 hint: Consider setting the necessary environment variables by running:
3003 GUIX_PROFILE="$HOME/.guix-profile"
3004 . "$GUIX_PROFILE/etc/profile"
3006 Alternately, see `guix package --search-paths -p "$HOME/.guix-profile"'.
3009 Indeed, you must now tell your shell where @command{emacs} and other
3010 programs installed with Guix are to be found. Pasting the two lines
3011 above will do just that: it will add
3012 @code{$HOME/.guix-profile/bin}---which is where the installed package
3013 is---to the @code{PATH} environment variable. You can paste these two
3014 lines in your shell so they take effect right away, but more importantly
3015 you should add them to @file{~/.bash_profile} (or equivalent file if you
3016 do not use Bash) so that environment variables are set next time you
3017 spawn a shell. You only need to do this once and other search paths
3018 environment variables will be taken care of similarly---e.g., if you
3019 eventually install @code{python} and Python libraries,
3020 @env{GUIX_PYTHONPATH} will be defined.
3022 You can go on installing packages at your will. To list installed
3026 guix package --list-installed
3029 To remove a package, you would unsurprisingly run @command{guix remove}.
3030 A distinguishing feature is the ability to @dfn{roll back} any operation
3031 you made---installation, removal, upgrade---by simply typing:
3034 guix package --roll-back
3037 This is because each operation is in fact a @dfn{transaction} that
3038 creates a new @dfn{generation}. These generations and the difference
3039 between them can be displayed by running:
3042 guix package --list-generations
3045 Now you know the basics of package management!
3047 @quotation Going further
3048 @xref{Package Management}, for more about package management. You may
3049 like @dfn{declarative} package management with @command{guix package
3050 --manifest}, managing separate @dfn{profiles} with @option{--profile},
3051 deleting old generations, collecting garbage, and other nifty features
3052 that will come in handy as you become more familiar with Guix. If you
3053 are a developer, @pxref{Development} for additional tools. And if
3054 you're curious, @pxref{Features}, to peek under the hood.
3057 Once you've installed a set of packages, you will want to periodically
3058 @emph{upgrade} them to the latest and greatest version. To do that, you
3059 will first pull the latest revision of Guix and its package collection:
3065 The end result is a new @command{guix} command, under
3066 @file{~/.config/guix/current/bin}. Unless you're on Guix System, the
3067 first time you run @command{guix pull}, be sure to follow the hint that
3068 the command prints and, similar to what we saw above, paste these two
3069 lines in your terminal and @file{.bash_profile}:
3072 GUIX_PROFILE="$HOME/.config/guix/current"
3073 . "$GUIX_PROFILE/etc/profile"
3077 You must also instruct your shell to point to this new @command{guix}:
3083 At this point, you're running a brand new Guix. You can thus go ahead
3084 and actually upgrade all the packages you previously installed:
3090 As you run this command, you will see that binaries are downloaded (or
3091 perhaps some packages are built), and eventually you end up with the
3092 upgraded packages. Should one of these upgraded packages not be to your
3093 liking, remember you can always roll back!
3095 You can display the exact revision of Guix you're currently using by
3102 The information it displays is @emph{all it takes to reproduce the exact
3103 same Guix}, be it at a different point in time or on a different
3106 @quotation Going further
3107 @xref{Invoking guix pull}, for more information. @xref{Channels}, on
3108 how to specify additional @dfn{channels} to pull packages from, how to
3109 replicate Guix, and more. You may also find @command{time-machine}
3110 handy (@pxref{Invoking guix time-machine}).
3113 If you installed Guix System, one of the first things you'll want to do
3114 is to upgrade your system. Once you've run @command{guix pull} to get
3115 the latest Guix, you can upgrade the system like this:
3118 sudo guix system reconfigure /etc/config.scm
3121 Upon completion, the system runs the latest versions of its software
3122 packages. When you eventually reboot, you'll notice a sub-menu in the
3123 bootloader that reads ``Old system generations'': it's what allows you
3124 to boot @emph{an older generation of your system}, should the latest
3125 generation be ``broken'' or otherwise unsatisfying. Just like for
3126 packages, you can always @emph{roll back} to a previous generation
3127 @emph{of the whole system}:
3130 sudo guix system roll-back
3133 There are many things you'll probably want to tweak on your system:
3134 adding new user accounts, adding new system services, fiddling with the
3135 configuration of those services, etc. The system configuration is
3136 @emph{entirely} described in the @file{/etc/config.scm} file.
3137 @xref{Using the Configuration System}, to learn how to change it.
3139 Now you know enough to get started!
3141 @quotation Resources
3142 The rest of this manual provides a reference for all things Guix. Here
3143 are some additional resources you may find useful:
3147 @xref{Top,,, guix-cookbook, The GNU Guix Cookbook}, for a list of
3148 ``how-to'' style of recipes for a variety of applications.
3151 The @uref{https://guix.gnu.org/guix-refcard.pdf, GNU Guix Reference
3152 Card} lists in two pages most of the commands and options you'll ever
3156 The web site contains @uref{https://guix.gnu.org/en/videos/,
3157 instructional videos} covering topics such as everyday use of Guix, how
3158 to get help, and how to become a contributor.
3161 @xref{Documentation}, to learn how to access documentation on your
3165 We hope you will enjoy Guix as much as the community enjoys building it!
3168 @c *********************************************************************
3169 @node Package Management
3170 @chapter Package Management
3173 The purpose of GNU Guix is to allow users to easily install, upgrade, and
3174 remove software packages, without having to know about their build
3175 procedures or dependencies. Guix also goes beyond this obvious set of
3178 This chapter describes the main features of Guix, as well as the
3179 package management tools it provides. Along with the command-line
3180 interface described below (@pxref{Invoking guix package, @code{guix
3181 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
3182 emacs-guix, The Emacs-Guix Reference Manual}), after installing
3183 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
3187 guix install emacs-guix
3191 * Features:: How Guix will make your life brighter.
3192 * Invoking guix package:: Package installation, removal, etc.
3193 * Substitutes:: Downloading pre-built binaries.
3194 * Packages with Multiple Outputs:: Single source package, multiple outputs.
3195 * Invoking guix gc:: Running the garbage collector.
3196 * Invoking guix pull:: Fetching the latest Guix and distribution.
3197 * Invoking guix time-machine:: Running an older revision of Guix.
3198 * Inferiors:: Interacting with another revision of Guix.
3199 * Invoking guix describe:: Display information about your Guix revision.
3200 * Invoking guix archive:: Exporting and importing store files.
3206 Here we assume you've already made your first steps with Guix
3207 (@pxref{Getting Started}) and would like to get an overview about what's
3208 going on under the hood.
3210 When using Guix, each package ends up in the @dfn{package store}, in its
3211 own directory---something that resembles
3212 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
3214 Instead of referring to these directories, users have their own
3215 @dfn{profile}, which points to the packages that they actually want to
3216 use. These profiles are stored within each user's home directory, at
3217 @code{$HOME/.guix-profile}.
3219 For example, @code{alice} installs GCC 4.7.2. As a result,
3220 @file{/home/alice/.guix-profile/bin/gcc} points to
3221 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
3222 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
3223 simply continues to point to
3224 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
3225 coexist on the same system without any interference.
3227 The @command{guix package} command is the central tool to manage
3228 packages (@pxref{Invoking guix package}). It operates on the per-user
3229 profiles, and can be used @emph{with normal user privileges}.
3231 @cindex transactions
3232 The command provides the obvious install, remove, and upgrade
3233 operations. Each invocation is actually a @emph{transaction}: either
3234 the specified operation succeeds, or nothing happens. Thus, if the
3235 @command{guix package} process is terminated during the transaction,
3236 or if a power outage occurs during the transaction, then the user's
3237 profile remains in its previous state, and remains usable.
3239 In addition, any package transaction may be @emph{rolled back}. So, if,
3240 for example, an upgrade installs a new version of a package that turns
3241 out to have a serious bug, users may roll back to the previous instance
3242 of their profile, which was known to work well. Similarly, the global
3243 system configuration on Guix is subject to
3244 transactional upgrades and roll-back
3245 (@pxref{Using the Configuration System}).
3247 All packages in the package store may be @emph{garbage-collected}.
3248 Guix can determine which packages are still referenced by user
3249 profiles, and remove those that are provably no longer referenced
3250 (@pxref{Invoking guix gc}). Users may also explicitly remove old
3251 generations of their profile so that the packages they refer to can be
3254 @cindex reproducibility
3255 @cindex reproducible builds
3256 Guix takes a @dfn{purely functional} approach to package
3257 management, as described in the introduction (@pxref{Introduction}).
3258 Each @file{/gnu/store} package directory name contains a hash of all the
3259 inputs that were used to build that package---compiler, libraries, build
3260 scripts, etc. This direct correspondence allows users to make sure a
3261 given package installation matches the current state of their
3262 distribution. It also helps maximize @dfn{build reproducibility}:
3263 thanks to the isolated build environments that are used, a given build
3264 is likely to yield bit-identical files when performed on different
3265 machines (@pxref{Invoking guix-daemon, container}).
3268 This foundation allows Guix to support @dfn{transparent binary/source
3269 deployment}. When a pre-built binary for a @file{/gnu/store} item is
3270 available from an external source---a @dfn{substitute}, Guix just
3271 downloads it and unpacks it;
3272 otherwise, it builds the package from source, locally
3273 (@pxref{Substitutes}). Because build results are usually bit-for-bit
3274 reproducible, users do not have to trust servers that provide
3275 substitutes: they can force a local build and @emph{challenge} providers
3276 (@pxref{Invoking guix challenge}).
3278 Control over the build environment is a feature that is also useful for
3279 developers. The @command{guix shell} command allows developers of
3280 a package to quickly set up the right development environment for their
3281 package, without having to manually install the dependencies of the
3282 package into their profile (@pxref{Invoking guix shell}).
3284 @cindex replication, of software environments
3285 @cindex provenance tracking, of software artifacts
3286 All of Guix and its package definitions is version-controlled, and
3287 @command{guix pull} allows you to ``travel in time'' on the history of Guix
3288 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
3289 Guix instance on a different machine or at a later point in time, which in
3290 turn allows you to @emph{replicate complete software environments}, while
3291 retaining precise @dfn{provenance tracking} of the software.
3293 @node Invoking guix package
3294 @section Invoking @command{guix package}
3296 @cindex installing packages
3297 @cindex removing packages
3298 @cindex package installation
3299 @cindex package removal
3301 The @command{guix package} command is the tool that allows users to
3302 install, upgrade, and remove packages, as well as rolling back to
3303 previous configurations. These operations work on a user
3304 @dfn{profile}---a directory of installed packages. Each user has a
3305 default profile in @file{$HOME/.guix-profile}.
3306 The command operates only on the user's own profile,
3307 and works with normal user privileges (@pxref{Features}). Its syntax
3311 guix package @var{options}
3314 @cindex transactions
3315 Primarily, @var{options} specifies the operations to be performed during
3316 the transaction. Upon completion, a new profile is created, but
3317 previous @dfn{generations} of the profile remain available, should the user
3320 For example, to remove @code{lua} and install @code{guile} and
3321 @code{guile-cairo} in a single transaction:
3324 guix package -r lua -i guile guile-cairo
3327 @cindex aliases, for @command{guix package}
3328 For your convenience, we also provide the following aliases:
3332 @command{guix search} is an alias for @command{guix package -s},
3334 @command{guix install} is an alias for @command{guix package -i},
3336 @command{guix remove} is an alias for @command{guix package -r},
3338 @command{guix upgrade} is an alias for @command{guix package -u},
3340 and @command{guix show} is an alias for @command{guix package --show=}.
3343 These aliases are less expressive than @command{guix package} and provide
3344 fewer options, so in some cases you'll probably want to use @command{guix
3347 @command{guix package} also supports a @dfn{declarative approach}
3348 whereby the user specifies the exact set of packages to be available and
3349 passes it @i{via} the @option{--manifest} option
3350 (@pxref{profile-manifest, @option{--manifest}}).
3353 For each user, a symlink to the user's default profile is automatically
3354 created in @file{$HOME/.guix-profile}. This symlink always points to the
3355 current generation of the user's default profile. Thus, users can add
3356 @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
3357 variable, and so on.
3358 @cindex search paths
3359 If you are not using Guix System, consider adding the
3360 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
3361 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
3362 shells get all the right environment variable definitions:
3365 GUIX_PROFILE="$HOME/.guix-profile" ; \
3366 source "$GUIX_PROFILE/etc/profile"
3369 In a multi-user setup, user profiles are stored in a place registered as
3370 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
3371 to (@pxref{Invoking guix gc}). That directory is normally
3372 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
3373 @var{localstatedir} is the value passed to @code{configure} as
3374 @option{--localstatedir}, and @var{user} is the user name. The
3375 @file{per-user} directory is created when @command{guix-daemon} is
3376 started, and the @var{user} sub-directory is created by @command{guix
3379 The @var{options} can be among the following:
3383 @item --install=@var{package} @dots{}
3384 @itemx -i @var{package} @dots{}
3385 Install the specified @var{package}s.
3387 Each @var{package} may specify either a simple package name, such as
3388 @code{guile}, or a package name followed by an at-sign and version number,
3389 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
3390 case, the newest version prefixed by @code{1.8} is selected).
3392 If no version number is specified, the
3393 newest available version will be selected. In addition, @var{package}
3394 may contain a colon, followed by the name of one of the outputs of the
3395 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
3396 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
3397 name (and optionally version) are searched for among the GNU
3398 distribution modules (@pxref{Package Modules}).
3400 @cindex propagated inputs
3401 Sometimes packages have @dfn{propagated inputs}: these are dependencies
3402 that automatically get installed along with the required package
3403 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
3404 @code{package} objects}, for information about propagated inputs in
3405 package definitions).
3407 @anchor{package-cmd-propagated-inputs}
3408 An example is the GNU MPC library: its C header files refer to those of
3409 the GNU MPFR library, which in turn refer to those of the GMP library.
3410 Thus, when installing MPC, the MPFR and GMP libraries also get installed
3411 in the profile; removing MPC also removes MPFR and GMP---unless they had
3412 also been explicitly installed by the user.
3414 Besides, packages sometimes rely on the definition of environment
3415 variables for their search paths (see explanation of
3416 @option{--search-paths} below). Any missing or possibly incorrect
3417 environment variable definitions are reported here.
3419 @item --install-from-expression=@var{exp}
3421 Install the package @var{exp} evaluates to.
3423 @var{exp} must be a Scheme expression that evaluates to a
3424 @code{<package>} object. This option is notably useful to disambiguate
3425 between same-named variants of a package, with expressions such as
3426 @code{(@@ (gnu packages base) guile-final)}.
3428 Note that this option installs the first output of the specified
3429 package, which may be insufficient when needing a specific output of a
3430 multiple-output package.
3432 @item --install-from-file=@var{file}
3433 @itemx -f @var{file}
3434 Install the package that the code within @var{file} evaluates to.
3436 As an example, @var{file} might contain a definition like this
3437 (@pxref{Defining Packages}):
3440 @include package-hello.scm
3443 Developers may find it useful to include such a @file{guix.scm} file
3444 in the root of their project source tree that can be used to test
3445 development snapshots and create reproducible development environments
3446 (@pxref{Invoking guix shell}).
3448 The @var{file} may also contain a JSON representation of one or more
3449 package definitions. Running @code{guix package -f} on
3450 @file{hello.json} with the following contents would result in installing
3451 the package @code{greeter} after building @code{myhello}:
3454 @verbatiminclude package-hello.json
3457 @item --remove=@var{package} @dots{}
3458 @itemx -r @var{package} @dots{}
3459 Remove the specified @var{package}s.
3461 As for @option{--install}, each @var{package} may specify a version number
3462 and/or output name in addition to the package name. For instance,
3463 @samp{-r glibc:debug} would remove the @code{debug} output of
3466 @item --upgrade[=@var{regexp} @dots{}]
3467 @itemx -u [@var{regexp} @dots{}]
3468 @cindex upgrading packages
3469 Upgrade all the installed packages. If one or more @var{regexp}s are
3470 specified, upgrade only installed packages whose name matches a
3471 @var{regexp}. Also see the @option{--do-not-upgrade} option below.
3473 Note that this upgrades package to the latest version of packages found
3474 in the distribution currently installed. To update your distribution,
3475 you should regularly run @command{guix pull} (@pxref{Invoking guix
3478 @cindex package transformations, upgrades
3479 When upgrading, package transformations that were originally applied
3480 when creating the profile are automatically re-applied (@pxref{Package
3481 Transformation Options}). For example, assume you first installed Emacs
3482 from the tip of its development branch with:
3485 guix install emacs-next --with-branch=emacs-next=master
3488 Next time you run @command{guix upgrade}, Guix will again pull the tip
3489 of the Emacs development branch and build @code{emacs-next} from that
3492 Note that transformation options such as @option{--with-branch} and
3493 @option{--with-source} depend on external state; it is up to you to
3494 ensure that they work as expected. You can also discard a
3495 transformations that apply to a package by running:
3498 guix install @var{package}
3501 @item --do-not-upgrade[=@var{regexp} @dots{}]
3502 When used together with the @option{--upgrade} option, do @emph{not}
3503 upgrade any packages whose name matches a @var{regexp}. For example, to
3504 upgrade all packages in the current profile except those containing the
3505 substring ``emacs'':
3508 $ guix package --upgrade . --do-not-upgrade emacs
3511 @item @anchor{profile-manifest}--manifest=@var{file}
3512 @itemx -m @var{file}
3513 @cindex profile declaration
3514 @cindex profile manifest
3515 Create a new generation of the profile from the manifest object
3516 returned by the Scheme code in @var{file}. This option can be repeated
3517 several times, in which case the manifests are concatenated.
3519 This allows you to @emph{declare} the profile's contents rather than
3520 constructing it through a sequence of @option{--install} and similar
3521 commands. The advantage is that @var{file} can be put under version
3522 control, copied to different machines to reproduce the same profile, and
3525 @var{file} must return a @dfn{manifest} object, which is roughly a list
3528 @findex packages->manifest
3530 (use-package-modules guile emacs)
3535 ;; Use a specific package output.
3536 (list guile-2.0 "debug")))
3539 @xref{Writing Manifests}, for information on how to write a manifest.
3540 @xref{export-manifest, @option{--export-manifest}}, to learn how to
3541 obtain a manifest file from an existing profile.
3544 @cindex rolling back
3545 @cindex undoing transactions
3546 @cindex transactions, undoing
3547 Roll back to the previous @dfn{generation} of the profile---i.e., undo
3548 the last transaction.
3550 When combined with options such as @option{--install}, roll back occurs
3551 before any other actions.
3553 When rolling back from the first generation that actually contains
3554 installed packages, the profile is made to point to the @dfn{zeroth
3555 generation}, which contains no files apart from its own metadata.
3557 After having rolled back, installing, removing, or upgrading packages
3558 overwrites previous future generations. Thus, the history of the
3559 generations in a profile is always linear.
3561 @item --switch-generation=@var{pattern}
3562 @itemx -S @var{pattern}
3564 Switch to a particular generation defined by @var{pattern}.
3566 @var{pattern} may be either a generation number or a number prefixed
3567 with ``+'' or ``-''. The latter means: move forward/backward by a
3568 specified number of generations. For example, if you want to return to
3569 the latest generation after @option{--roll-back}, use
3570 @option{--switch-generation=+1}.
3572 The difference between @option{--roll-back} and
3573 @option{--switch-generation=-1} is that @option{--switch-generation} will
3574 not make a zeroth generation, so if a specified generation does not
3575 exist, the current generation will not be changed.
3577 @item --search-paths[=@var{kind}]
3578 @cindex search paths
3579 Report environment variable definitions, in Bash syntax, that may be
3580 needed in order to use the set of installed packages. These environment
3581 variables are used to specify @dfn{search paths} for files used by some
3582 of the installed packages.
3584 For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
3585 environment variables to be defined so it can look for headers and
3586 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
3587 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
3588 library are installed in the profile, then @option{--search-paths} will
3589 suggest setting these variables to @file{@var{profile}/include} and
3590 @file{@var{profile}/lib}, respectively (@pxref{Search Paths}, for info
3591 on search path specifications associated with packages.)
3593 The typical use case is to define these environment variables in the
3597 $ eval $(guix package --search-paths)
3600 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
3601 meaning that the returned environment variable definitions will either
3602 be exact settings, or prefixes or suffixes of the current value of these
3603 variables. When omitted, @var{kind} defaults to @code{exact}.
3605 This option can also be used to compute the @emph{combined} search paths
3606 of several profiles. Consider this example:
3609 $ guix package -p foo -i guile
3610 $ guix package -p bar -i guile-json
3611 $ guix package -p foo -p bar --search-paths
3614 The last command above reports about the @env{GUILE_LOAD_PATH}
3615 variable, even though, taken individually, neither @file{foo} nor
3616 @file{bar} would lead to that recommendation.
3619 @cindex profile, choosing
3620 @item --profile=@var{profile}
3621 @itemx -p @var{profile}
3622 Use @var{profile} instead of the user's default profile.
3624 @var{profile} must be the name of a file that will be created upon
3625 completion. Concretely, @var{profile} will be a mere symbolic link
3626 (``symlink'') pointing to the actual profile where packages are
3630 $ guix install hello -p ~/code/my-profile
3632 $ ~/code/my-profile/bin/hello
3636 All it takes to get rid of the profile is to remove this symlink and its
3637 siblings that point to specific generations:
3640 $ rm ~/code/my-profile ~/code/my-profile-*-link
3643 @item --list-profiles
3644 List all the user's profiles:
3647 $ guix package --list-profiles
3648 /home/charlie/.guix-profile
3649 /home/charlie/code/my-profile
3650 /home/charlie/code/devel-profile
3651 /home/charlie/tmp/test
3654 When running as root, list all the profiles of all the users.
3656 @cindex collisions, in a profile
3657 @cindex colliding packages in profiles
3658 @cindex profile collisions
3659 @item --allow-collisions
3660 Allow colliding packages in the new profile. Use at your own risk!
3662 By default, @command{guix package} reports as an error @dfn{collisions}
3663 in the profile. Collisions happen when two or more different versions
3664 or variants of a given package end up in the profile.
3667 Use the bootstrap Guile to build the profile. This option is only
3668 useful to distribution developers.
3672 In addition to these actions, @command{guix package} supports the
3673 following options to query the current state of a profile, or the
3674 availability of packages:
3678 @item --search=@var{regexp}
3679 @itemx -s @var{regexp}
3680 @anchor{guix-search}
3681 @cindex searching for packages
3682 List the available packages whose name, synopsis, or description matches
3683 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3684 Print all the metadata of matching packages in
3685 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3686 GNU recutils manual}).
3688 This allows specific fields to be extracted using the @command{recsel}
3689 command, for instance:
3692 $ guix package -s malloc | recsel -p name,version,relevance
3706 Similarly, to show the name of all the packages available under the
3707 terms of the GNU@tie{}LGPL version 3:
3710 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3717 It is also possible to refine search results using several @code{-s} flags to
3718 @command{guix package}, or several arguments to @command{guix search}. For
3719 example, the following command returns a list of board games (this time using
3720 the @command{guix search} alias):
3723 $ guix search '\<board\>' game | recsel -p name
3728 If we were to omit @code{-s game}, we would also get software packages
3729 that deal with printed circuit boards; removing the angle brackets
3730 around @code{board} would further add packages that have to do with
3733 And now for a more elaborate example. The following command searches
3734 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3735 libraries, and prints the name and synopsis of the matching packages:
3738 $ guix search crypto library | \
3739 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3743 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3744 information on @dfn{selection expressions} for @code{recsel -e}.
3746 @item --show=@var{package}
3747 Show details about @var{package}, taken from the list of available packages, in
3748 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3752 $ guix package --show=guile | recsel -p name,version
3764 You may also specify the full name of a package to only get details about a
3765 specific version of it (this time using the @command{guix show} alias):
3767 $ guix show guile@@3.0.5 | recsel -p name,version
3772 @item --list-installed[=@var{regexp}]
3773 @itemx -I [@var{regexp}]
3774 List the currently installed packages in the specified profile, with the
3775 most recently installed packages shown last. When @var{regexp} is
3776 specified, list only installed packages whose name matches @var{regexp}.
3778 For each installed package, print the following items, separated by
3779 tabs: the package name, its version string, the part of the package that
3780 is installed (for instance, @code{out} for the default output,
3781 @code{include} for its headers, etc.), and the path of this package in
3784 @item --list-available[=@var{regexp}]
3785 @itemx -A [@var{regexp}]
3786 List packages currently available in the distribution for this system
3787 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3788 available packages whose name matches @var{regexp}.
3790 For each package, print the following items separated by tabs: its name,
3791 its version string, the parts of the package (@pxref{Packages with
3792 Multiple Outputs}), and the source location of its definition.
3794 @item --list-generations[=@var{pattern}]
3795 @itemx -l [@var{pattern}]
3797 Return a list of generations along with their creation dates; for each
3798 generation, show the installed packages, with the most recently
3799 installed packages shown last. Note that the zeroth generation is never
3802 For each installed package, print the following items, separated by
3803 tabs: the name of a package, its version string, the part of the package
3804 that is installed (@pxref{Packages with Multiple Outputs}), and the
3805 location of this package in the store.
3807 When @var{pattern} is used, the command returns only matching
3808 generations. Valid patterns include:
3811 @item @emph{Integers and comma-separated integers}. Both patterns denote
3812 generation numbers. For instance, @option{--list-generations=1} returns
3815 And @option{--list-generations=1,8,2} outputs three generations in the
3816 specified order. Neither spaces nor trailing commas are allowed.
3818 @item @emph{Ranges}. @option{--list-generations=2..9} prints the
3819 specified generations and everything in between. Note that the start of
3820 a range must be smaller than its end.
3822 It is also possible to omit the endpoint. For example,
3823 @option{--list-generations=2..}, returns all generations starting from the
3826 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3827 or months by passing an integer along with the first letter of the
3828 duration. For example, @option{--list-generations=20d} lists generations
3829 that are up to 20 days old.
3832 @item --delete-generations[=@var{pattern}]
3833 @itemx -d [@var{pattern}]
3834 When @var{pattern} is omitted, delete all generations except the current
3837 This command accepts the same patterns as @option{--list-generations}.
3838 When @var{pattern} is specified, delete the matching generations. When
3839 @var{pattern} specifies a duration, generations @emph{older} than the
3840 specified duration match. For instance, @option{--delete-generations=1m}
3841 deletes generations that are more than one month old.
3843 If the current generation matches, it is @emph{not} deleted. Also, the
3844 zeroth generation is never deleted.
3846 Note that deleting generations prevents rolling back to them.
3847 Consequently, this command must be used with care.
3849 @cindex manifest, exporting
3850 @anchor{export-manifest}
3851 @item --export-manifest
3852 Write to standard output a manifest suitable for @option{--manifest}
3853 corresponding to the chosen profile(s).
3855 This option is meant to help you migrate from the ``imperative''
3856 operating mode---running @command{guix install}, @command{guix upgrade},
3857 etc.---to the declarative mode that @option{--manifest} offers.
3859 Be aware that the resulting manifest @emph{approximates} what your
3860 profile actually contains; for instance, depending on how your profile
3861 was created, it can refer to packages or package versions that are not
3862 exactly what you specified.
3864 Keep in mind that a manifest is purely symbolic: it only contains
3865 package names and possibly versions, and their meaning varies over time.
3866 If you wish to ``pin'' channels to the revisions that were used to build
3867 the profile(s), see @option{--export-channels} below.
3869 @cindex pinning, channel revisions of a profile
3870 @item --export-channels
3871 Write to standard output the list of channels used by the chosen
3872 profile(s), in a format suitable for @command{guix pull --channels} or
3873 @command{guix time-machine --channels} (@pxref{Channels}).
3875 Together with @option{--export-manifest}, this option provides
3876 information allowing you to replicate the current profile
3877 (@pxref{Replicating Guix}).
3879 However, note that the output of this command @emph{approximates} what
3880 was actually used to build this profile. In particular, a single
3881 profile might have been built from several different revisions of the
3882 same channel. In that case, @option{--export-manifest} chooses the last
3883 one and writes the list of other revisions in a comment. If you really
3884 need to pick packages from different channel revisions, you can use
3885 inferiors in your manifest to do so (@pxref{Inferiors}).
3887 Together with @option{--export-manifest}, this is a good starting point
3888 if you are willing to migrate from the ``imperative'' model to the fully
3889 declarative model consisting of a manifest file along with a channels
3890 file pinning the exact channel revision(s) you want.
3893 Finally, since @command{guix package} may actually start build
3894 processes, it supports all the common build options (@pxref{Common Build
3895 Options}). It also supports package transformation options, such as
3896 @option{--with-source}, and preserves them across upgrades
3897 (@pxref{Package Transformation Options}).
3900 @section Substitutes
3903 @cindex pre-built binaries
3904 Guix supports transparent source/binary deployment, which means that it
3905 can either build things locally, or download pre-built items from a
3906 server, or both. We call these pre-built items @dfn{substitutes}---they
3907 are substitutes for local build results. In many cases, downloading a
3908 substitute is much faster than building things locally.
3910 Substitutes can be anything resulting from a derivation build
3911 (@pxref{Derivations}). Of course, in the common case, they are
3912 pre-built package binaries, but source tarballs, for instance, which
3913 also result from derivation builds, can be available as substitutes.
3916 * Official Substitute Servers:: One particular source of substitutes.
3917 * Substitute Server Authorization:: How to enable or disable substitutes.
3918 * Getting Substitutes from Other Servers:: Substitute diversity.
3919 * Substitute Authentication:: How Guix verifies substitutes.
3920 * Proxy Settings:: How to get substitutes via proxy.
3921 * Substitution Failure:: What happens when substitution fails.
3922 * On Trusting Binaries:: How can you trust that binary blob?
3925 @node Official Substitute Servers
3926 @subsection Official Substitute Servers
3929 @code{@value{SUBSTITUTE-SERVER-1}} and
3930 @code{@value{SUBSTITUTE-SERVER-2}} are both front-ends to official build
3931 farms that build packages from Guix continuously for some architectures,
3932 and make them available as substitutes. These are the default source of
3933 substitutes; which can be overridden by passing the
3934 @option{--substitute-urls} option either to @command{guix-daemon}
3935 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3936 or to client tools such as @command{guix package}
3937 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3940 Substitute URLs can be either HTTP or HTTPS.
3941 HTTPS is recommended because communications are encrypted; conversely,
3942 using HTTP makes all communications visible to an eavesdropper, who
3943 could use the information gathered to determine, for instance, whether
3944 your system has unpatched security vulnerabilities.
3946 Substitutes from the official build farms are enabled by default when
3947 using Guix System (@pxref{GNU Distribution}). However,
3948 they are disabled by default when using Guix on a foreign distribution,
3949 unless you have explicitly enabled them via one of the recommended
3950 installation steps (@pxref{Installation}). The following paragraphs
3951 describe how to enable or disable substitutes for the official build
3952 farm; the same procedure can also be used to enable substitutes for any
3953 other substitute server.
3955 @node Substitute Server Authorization
3956 @subsection Substitute Server Authorization
3959 @cindex substitutes, authorization thereof
3960 @cindex access control list (ACL), for substitutes
3961 @cindex ACL (access control list), for substitutes
3962 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER-1}}, @code{@value{SUBSTITUTE-SERVER-2}} or a mirror, you
3963 must add the relevant public key to the access control list (ACL) of archive
3964 imports, using the @command{guix archive} command (@pxref{Invoking guix
3965 archive}). Doing so implies that you trust the substitute server to not
3966 be compromised and to serve genuine substitutes.
3969 If you are using Guix System, you can skip this section: Guix System
3970 authorizes substitutes from @code{@value{SUBSTITUTE-SERVER-1}} and
3971 @code{@value{SUBSTITUTE-SERVER-2}} by default.
3974 The public keys for each of the project maintained substitute servers
3975 are installed along with Guix, in @code{@var{prefix}/share/guix/}, where
3976 @var{prefix} is the installation prefix of Guix. If you installed Guix
3977 from source, make sure you checked the GPG signature of
3978 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3979 Then, you can run something like this:
3982 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
3983 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
3986 Once this is in place, the output of a command like @code{guix build}
3987 should change from something like:
3990 $ guix build emacs --dry-run
3991 The following derivations would be built:
3992 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3993 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3994 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3995 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
4003 $ guix build emacs --dry-run
4004 112.3 MB would be downloaded:
4005 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
4006 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
4007 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
4008 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
4013 The text changed from ``The following derivations would be built'' to
4014 ``112.3 MB would be downloaded''. This indicates that substitutes from
4015 the configured substitute servers are usable and will be downloaded,
4016 when possible, for future builds.
4018 @cindex substitutes, how to disable
4019 The substitute mechanism can be disabled globally by running
4020 @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
4021 guix-daemon}). It can also be disabled temporarily by passing the
4022 @option{--no-substitutes} option to @command{guix package},
4023 @command{guix build}, and other command-line tools.
4025 @node Getting Substitutes from Other Servers
4026 @subsection Getting Substitutes from Other Servers
4028 @cindex substitute servers, adding more
4029 Guix can look up and fetch substitutes from several servers. This is
4030 useful when you are using packages from additional channels for which
4031 the official server does not have substitutes but another server
4032 provides them. Another situation where this is useful is when you would
4033 prefer to download from your organization's substitute server, resorting
4034 to the official server only as a fallback or dismissing it altogether.
4036 You can give Guix a list of substitute server URLs and it will check
4037 them in the specified order. You also need to explicitly authorize the
4038 public keys of substitute servers to instruct Guix to accept the
4039 substitutes they sign.
4041 On Guix System, this is achieved by modifying the configuration of the
4042 @code{guix} service. Since the @code{guix} service is part of the
4043 default lists of services, @code{%base-services} and
4044 @code{%desktop-services}, you can use @code{modify-services} to change
4045 its configuration and add the URLs and substitute keys that you want
4046 (@pxref{Service Reference, @code{modify-services}}).
4048 As an example, suppose you want to fetch substitutes from
4049 @code{guix.example.org} and to authorize the signing key of that server,
4050 in addition to the default @code{@value{SUBSTITUTE-SERVER-1}} and
4051 @code{@value{SUBSTITUTE-SERVER-2}}. The resulting operating system
4052 configuration will look something like:
4058 ;; Assume we're starting from '%desktop-services'. Replace it
4059 ;; with the list of services you're actually using.
4060 (modify-services %desktop-services
4061 (guix-service-type config =>
4065 (append (list "https://guix.example.org")
4066 %default-substitute-urls))
4068 (append (list (local-file "./key.pub"))
4069 %default-authorized-guix-keys)))))))
4072 This assumes that the file @file{key.pub} contains the signing key of
4073 @code{guix.example.org}. With this change in place in your operating
4074 system configuration file (say @file{/etc/config.scm}), you can
4075 reconfigure and restart the @code{guix-daemon} service or reboot so the
4076 changes take effect:
4079 $ sudo guix system reconfigure /etc/config.scm
4080 $ sudo herd restart guix-daemon
4083 If you're running Guix on a ``foreign distro'', you would instead take
4084 the following steps to get substitutes from additional servers:
4088 Edit the service configuration file for @code{guix-daemon}; when using
4089 systemd, this is normally
4090 @file{/etc/systemd/system/guix-daemon.service}. Add the
4091 @option{--substitute-urls} option on the @command{guix-daemon} command
4092 line and list the URLs of interest (@pxref{daemon-substitute-urls,
4093 @code{guix-daemon --substitute-urls}}):
4096 @dots{} --substitute-urls='https://guix.example.org @value{SUBSTITUTE-URLS}'
4100 Restart the daemon. For systemd, it goes like this:
4103 systemctl daemon-reload
4104 systemctl restart guix-daemon.service
4108 Authorize the key of the new server (@pxref{Invoking guix archive}):
4111 guix archive --authorize < key.pub
4114 Again this assumes @file{key.pub} contains the public key that
4115 @code{guix.example.org} uses to sign substitutes.
4118 Now you're all set! Substitutes will be preferably taken from
4119 @code{https://guix.example.org}, using
4120 @code{@value{SUBSTITUTE-SERVER-1}} then
4121 @code{@value{SUBSTITUTE-SERVER-2}} as fallback options. Of course you
4122 can list as many substitute servers as you like, with the caveat that
4123 substitute lookup can be slowed down if too many servers need to be
4126 Note that there are also situations where one may want to add the URL of
4127 a substitute server @emph{without} authorizing its key.
4128 @xref{Substitute Authentication}, to understand this fine point.
4130 @node Substitute Authentication
4131 @subsection Substitute Authentication
4133 @cindex digital signatures
4134 Guix detects and raises an error when attempting to use a substitute
4135 that has been tampered with. Likewise, it ignores substitutes that are
4136 not signed, or that are not signed by one of the keys listed in the ACL.
4138 There is one exception though: if an unauthorized server provides
4139 substitutes that are @emph{bit-for-bit identical} to those provided by
4140 an authorized server, then the unauthorized server becomes eligible for
4141 downloads. For example, assume we have chosen two substitute servers
4145 --substitute-urls="https://a.example.org https://b.example.org"
4149 @cindex reproducible builds
4150 If the ACL contains only the key for @samp{b.example.org}, and if
4151 @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
4152 then Guix will download substitutes from @samp{a.example.org} because it
4153 comes first in the list and can be considered a mirror of
4154 @samp{b.example.org}. In practice, independent build machines usually
4155 produce the same binaries, thanks to bit-reproducible builds (see
4158 When using HTTPS, the server's X.509 certificate is @emph{not} validated
4159 (in other words, the server is not authenticated), contrary to what
4160 HTTPS clients such as Web browsers usually do. This is because Guix
4161 authenticates substitute information itself, as explained above, which
4162 is what we care about (whereas X.509 certificates are about
4163 authenticating bindings between domain names and public keys).
4165 @node Proxy Settings
4166 @subsection Proxy Settings
4170 Substitutes are downloaded over HTTP or HTTPS@. The @env{http_proxy} and
4171 @env{https_proxy} environment variables can be set in the environment of
4172 @command{guix-daemon} and are honored for downloads of substitutes.
4173 Note that the value of those environment variables in the environment
4174 where @command{guix build}, @command{guix package}, and other client
4175 commands are run has @emph{absolutely no effect}.
4177 @node Substitution Failure
4178 @subsection Substitution Failure
4180 Even when a substitute for a derivation is available, sometimes the
4181 substitution attempt will fail. This can happen for a variety of
4182 reasons: the substitute server might be offline, the substitute may
4183 recently have been deleted, the connection might have been interrupted,
4186 When substitutes are enabled and a substitute for a derivation is
4187 available, but the substitution attempt fails, Guix will attempt to
4188 build the derivation locally depending on whether or not
4189 @option{--fallback} was given (@pxref{fallback-option,, common build
4190 option @option{--fallback}}). Specifically, if @option{--fallback} was
4191 omitted, then no local build will be performed, and the derivation is
4192 considered to have failed. However, if @option{--fallback} was given,
4193 then Guix will attempt to build the derivation locally, and the success
4194 or failure of the derivation depends on the success or failure of the
4195 local build. Note that when substitutes are disabled or no substitute
4196 is available for the derivation in question, a local build will
4197 @emph{always} be performed, regardless of whether or not
4198 @option{--fallback} was given.
4200 To get an idea of how many substitutes are available right now, you can
4201 try running the @command{guix weather} command (@pxref{Invoking guix
4202 weather}). This command provides statistics on the substitutes provided
4205 @node On Trusting Binaries
4206 @subsection On Trusting Binaries
4208 @cindex trust, of pre-built binaries
4209 Today, each individual's control over their own computing is at the
4210 mercy of institutions, corporations, and groups with enough power and
4211 determination to subvert the computing infrastructure and exploit its
4212 weaknesses. While using substitutes can be convenient, we encourage
4213 users to also build on their own, or even run their own build farm, such
4214 that the project run substitute servers are less of an interesting
4215 target. One way to help is by publishing the software you build using
4216 @command{guix publish} so that others have one more choice of server to
4217 download substitutes from (@pxref{Invoking guix publish}).
4219 Guix has the foundations to maximize build reproducibility
4220 (@pxref{Features}). In most cases, independent builds of a given
4221 package or derivation should yield bit-identical results. Thus, through
4222 a diverse set of independent package builds, we can strengthen the
4223 integrity of our systems. The @command{guix challenge} command aims to
4224 help users assess substitute servers, and to assist developers in
4225 finding out about non-deterministic package builds (@pxref{Invoking guix
4226 challenge}). Similarly, the @option{--check} option of @command{guix
4227 build} allows users to check whether previously-installed substitutes
4228 are genuine by rebuilding them locally (@pxref{build-check,
4229 @command{guix build --check}}).
4231 In the future, we want Guix to have support to publish and retrieve
4232 binaries to/from other users, in a peer-to-peer fashion. If you would
4233 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
4235 @node Packages with Multiple Outputs
4236 @section Packages with Multiple Outputs
4238 @cindex multiple-output packages
4239 @cindex package outputs
4242 Often, packages defined in Guix have a single @dfn{output}---i.e., the
4243 source package leads to exactly one directory in the store. When running
4244 @command{guix install glibc}, one installs the default output of the
4245 GNU libc package; the default output is called @code{out}, but its name
4246 can be omitted as shown in this command. In this particular case, the
4247 default output of @code{glibc} contains all the C header files, shared
4248 libraries, static libraries, Info documentation, and other supporting
4251 Sometimes it is more appropriate to separate the various types of files
4252 produced from a single source package into separate outputs. For
4253 instance, the GLib C library (used by GTK+ and related packages)
4254 installs more than 20 MiB of reference documentation as HTML pages.
4255 To save space for users who do not need it, the documentation goes to a
4256 separate output, called @code{doc}. To install the main GLib output,
4257 which contains everything but the documentation, one would run:
4263 @cindex documentation
4264 The command to install its documentation is:
4267 guix install glib:doc
4270 Some packages install programs with different ``dependency footprints''.
4271 For instance, the WordNet package installs both command-line tools and
4272 graphical user interfaces (GUIs). The former depend solely on the C
4273 library, whereas the latter depend on Tcl/Tk and the underlying X
4274 libraries. In this case, we leave the command-line tools in the default
4275 output, whereas the GUIs are in a separate output. This allows users
4276 who do not need the GUIs to save space. The @command{guix size} command
4277 can help find out about such situations (@pxref{Invoking guix size}).
4278 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
4280 There are several such multiple-output packages in the GNU distribution.
4281 Other conventional output names include @code{lib} for libraries and
4282 possibly header files, @code{bin} for stand-alone programs, and
4283 @code{debug} for debugging information (@pxref{Installing Debugging
4284 Files}). The outputs of a packages are listed in the third column of
4285 the output of @command{guix package --list-available} (@pxref{Invoking
4289 @node Invoking guix gc
4290 @section Invoking @command{guix gc}
4292 @cindex garbage collector
4294 Packages that are installed, but not used, may be @dfn{garbage-collected}.
4295 The @command{guix gc} command allows users to explicitly run the garbage
4296 collector to reclaim space from the @file{/gnu/store} directory. It is
4297 the @emph{only} way to remove files from @file{/gnu/store}---removing
4298 files or directories manually may break it beyond repair!
4301 @cindex garbage collector roots
4302 The garbage collector has a set of known @dfn{roots}: any file under
4303 @file{/gnu/store} reachable from a root is considered @dfn{live} and
4304 cannot be deleted; any other file is considered @dfn{dead} and may be
4305 deleted. The set of garbage collector roots (``GC roots'' for short)
4306 includes default user profiles; by default, the symlinks under
4307 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
4308 added with @command{guix build --root}, for example (@pxref{Invoking
4309 guix build}). The @command{guix gc --list-roots} command lists them.
4311 Prior to running @code{guix gc --collect-garbage} to make space, it is
4312 often useful to remove old generations from user profiles; that way, old
4313 package builds referenced by those generations can be reclaimed. This
4314 is achieved by running @code{guix package --delete-generations}
4315 (@pxref{Invoking guix package}).
4317 Our recommendation is to run a garbage collection periodically, or when
4318 you are short on disk space. For instance, to guarantee that at least
4319 5@tie{}GB are available on your disk, simply run:
4325 It is perfectly safe to run as a non-interactive periodic job
4326 (@pxref{Scheduled Job Execution}, for how to set up such a job).
4327 Running @command{guix gc} with no arguments will collect as
4328 much garbage as it can, but that is often inconvenient: you may find
4329 yourself having to rebuild or re-download software that is ``dead'' from
4330 the GC viewpoint but that is necessary to build other pieces of
4331 software---e.g., the compiler tool chain.
4333 The @command{guix gc} command has three modes of operation: it can be
4334 used to garbage-collect any dead files (the default), to delete specific
4335 files (the @option{--delete} option), to print garbage-collector
4336 information, or for more advanced queries. The garbage collection
4337 options are as follows:
4340 @item --collect-garbage[=@var{min}]
4341 @itemx -C [@var{min}]
4342 Collect garbage---i.e., unreachable @file{/gnu/store} files and
4343 sub-directories. This is the default operation when no option is
4346 When @var{min} is given, stop once @var{min} bytes have been collected.
4347 @var{min} may be a number of bytes, or it may include a unit as a
4348 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
4349 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
4351 When @var{min} is omitted, collect all the garbage.
4353 @item --free-space=@var{free}
4354 @itemx -F @var{free}
4355 Collect garbage until @var{free} space is available under
4356 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
4357 as @code{500MiB}, as described above.
4359 When @var{free} or more is already available in @file{/gnu/store}, do
4360 nothing and exit immediately.
4362 @item --delete-generations[=@var{duration}]
4363 @itemx -d [@var{duration}]
4364 Before starting the garbage collection process, delete all the generations
4365 older than @var{duration}, for all the user profiles and home environment
4366 generations; when run as root, this
4367 applies to all the profiles @emph{of all the users}.
4369 For example, this command deletes all the generations of all your profiles
4370 that are older than 2 months (except generations that are current), and then
4371 proceeds to free space until at least 10 GiB are available:
4374 guix gc -d 2m -F 10G
4379 Attempt to delete all the store files and directories specified as
4380 arguments. This fails if some of the files are not in the store, or if
4381 they are still live.
4383 @item --list-failures
4384 List store items corresponding to cached build failures.
4386 This prints nothing unless the daemon was started with
4387 @option{--cache-failures} (@pxref{Invoking guix-daemon,
4388 @option{--cache-failures}}).
4391 List the GC roots owned by the user; when run as root, list @emph{all} the GC
4395 List store items in use by currently running processes. These store
4396 items are effectively considered GC roots: they cannot be deleted.
4398 @item --clear-failures
4399 Remove the specified store items from the failed-build cache.
4401 Again, this option only makes sense when the daemon is started with
4402 @option{--cache-failures}. Otherwise, it does nothing.
4405 Show the list of dead files and directories still present in the
4406 store---i.e., files and directories no longer reachable from any root.
4409 Show the list of live store files and directories.
4413 In addition, the references among existing store files can be queried:
4419 @cindex package dependencies
4420 List the references (respectively, the referrers) of store files given
4426 List the requisites of the store files passed as arguments. Requisites
4427 include the store files themselves, their references, and the references
4428 of these, recursively. In other words, the returned list is the
4429 @dfn{transitive closure} of the store files.
4431 @xref{Invoking guix size}, for a tool to profile the size of the closure
4432 of an element. @xref{Invoking guix graph}, for a tool to visualize
4433 the graph of references.
4437 Return the derivation(s) leading to the given store items
4438 (@pxref{Derivations}).
4440 For example, this command:
4443 guix gc --derivers $(guix package -I ^emacs$ | cut -f4)
4447 returns the @file{.drv} file(s) leading to the @code{emacs} package
4448 installed in your profile.
4450 Note that there may be zero matching @file{.drv} files, for instance
4451 because these files have been garbage-collected. There can also be more
4452 than one matching @file{.drv} due to fixed-output derivations.
4455 Lastly, the following options allow you to check the integrity of the
4456 store and to control disk usage.
4460 @item --verify[=@var{options}]
4461 @cindex integrity, of the store
4462 @cindex integrity checking
4463 Verify the integrity of the store.
4465 By default, make sure that all the store items marked as valid in the
4466 database of the daemon actually exist in @file{/gnu/store}.
4468 When provided, @var{options} must be a comma-separated list containing one
4469 or more of @code{contents} and @code{repair}.
4471 When passing @option{--verify=contents}, the daemon computes the
4472 content hash of each store item and compares it against its hash in the
4473 database. Hash mismatches are reported as data corruptions. Because it
4474 traverses @emph{all the files in the store}, this command can take a
4475 long time, especially on systems with a slow disk drive.
4477 @cindex repairing the store
4478 @cindex corruption, recovering from
4479 Using @option{--verify=repair} or @option{--verify=contents,repair}
4480 causes the daemon to try to repair corrupt store items by fetching
4481 substitutes for them (@pxref{Substitutes}). Because repairing is not
4482 atomic, and thus potentially dangerous, it is available only to the
4483 system administrator. A lightweight alternative, when you know exactly
4484 which items in the store are corrupt, is @command{guix build --repair}
4485 (@pxref{Invoking guix build}).
4488 @cindex deduplication
4489 Optimize the store by hard-linking identical files---this is
4490 @dfn{deduplication}.
4492 The daemon performs deduplication after each successful build or archive
4493 import, unless it was started with @option{--disable-deduplication}
4494 (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
4495 this option is primarily useful when the daemon was running with
4496 @option{--disable-deduplication}.
4500 @node Invoking guix pull
4501 @section Invoking @command{guix pull}
4503 @cindex upgrading Guix
4504 @cindex updating Guix
4505 @cindex @command{guix pull}
4507 @cindex security, @command{guix pull}
4508 @cindex authenticity, of code obtained with @command{guix pull}
4509 Packages are installed or upgraded to the latest version available in
4510 the distribution currently available on your local machine. To update
4511 that distribution, along with the Guix tools, you must run @command{guix
4512 pull}: the command downloads the latest Guix source code and package
4513 descriptions, and deploys it. Source code is downloaded from a
4514 @uref{https://git-scm.com, Git} repository, by default the official
4515 GNU@tie{}Guix repository, though this can be customized. @command{guix
4516 pull} ensures that the code it downloads is @emph{authentic} by
4517 verifying that commits are signed by Guix developers.
4519 Specifically, @command{guix pull} downloads code from the @dfn{channels}
4520 (@pxref{Channels}) specified by one of the followings, in this order:
4524 the @option{--channels} option;
4526 the user's @file{~/.config/guix/channels.scm} file;
4528 the system-wide @file{/etc/guix/channels.scm} file;
4530 the built-in default channels specified in the @code{%default-channels}
4534 On completion, @command{guix package} will use packages and package
4535 versions from this just-retrieved copy of Guix. Not only that, but all
4536 the Guix commands and Scheme modules will also be taken from that latest
4537 version. New @command{guix} sub-commands added by the update also
4540 Any user can update their Guix copy using @command{guix pull}, and the
4541 effect is limited to the user who ran @command{guix pull}. For
4542 instance, when user @code{root} runs @command{guix pull}, this has no
4543 effect on the version of Guix that user @code{alice} sees, and vice
4546 The result of running @command{guix pull} is a @dfn{profile} available
4547 under @file{~/.config/guix/current} containing the latest Guix. Thus,
4548 make sure to add it to the beginning of your search path so that you use
4549 the latest version, and similarly for the Info manual
4550 (@pxref{Documentation}):
4553 export PATH="$HOME/.config/guix/current/bin:$PATH"
4554 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
4557 The @option{--list-generations} or @option{-l} option lists past generations
4558 produced by @command{guix pull}, along with details about their provenance:
4562 Generation 1 Jun 10 2018 00:18:18
4564 repository URL: https://git.savannah.gnu.org/git/guix.git
4565 branch: origin/master
4566 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
4568 Generation 2 Jun 11 2018 11:02:49
4570 repository URL: https://git.savannah.gnu.org/git/guix.git
4571 branch: origin/master
4572 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
4574 Generation 3 Jun 13 2018 23:31:07 (current)
4576 repository URL: https://git.savannah.gnu.org/git/guix.git
4577 branch: origin/master
4578 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
4581 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
4582 describe the current status of Guix.
4584 This @code{~/.config/guix/current} profile works exactly like the profiles
4585 created by @command{guix package} (@pxref{Invoking guix package}). That
4586 is, you can list generations, roll back to the previous
4587 generation---i.e., the previous Guix---and so on:
4590 $ guix pull --roll-back
4591 switched from generation 3 to 2
4592 $ guix pull --delete-generations=1
4593 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4596 You can also use @command{guix package} (@pxref{Invoking guix package})
4597 to manage the profile by naming it explicitly:
4599 $ guix package -p ~/.config/guix/current --roll-back
4600 switched from generation 3 to 2
4601 $ guix package -p ~/.config/guix/current --delete-generations=1
4602 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4605 The @command{guix pull} command is usually invoked with no arguments,
4606 but it supports the following options:
4609 @item --url=@var{url}
4610 @itemx --commit=@var{commit}
4611 @itemx --branch=@var{branch}
4612 Download code for the @code{guix} channel from the specified @var{url}, at the
4613 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4614 string), or @var{branch}.
4616 @cindex @file{channels.scm}, configuration file
4617 @cindex configuration file for channels
4618 These options are provided for convenience, but you can also specify your
4619 configuration in the @file{~/.config/guix/channels.scm} file or using the
4620 @option{--channels} option (see below).
4622 @item --channels=@var{file}
4623 @itemx -C @var{file}
4624 Read the list of channels from @var{file} instead of
4625 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
4626 @var{file} must contain Scheme code that
4627 evaluates to a list of channel objects. @xref{Channels}, for more
4630 @cindex channel news
4633 Display news written by channel authors for their users for changes made
4634 since the previous generation (@pxref{Channels, Writing Channel News}).
4635 When @option{--details} is passed, additionally display new and upgraded
4638 You can view that information for previous generations with
4639 @command{guix pull -l}.
4641 @item --list-generations[=@var{pattern}]
4642 @itemx -l [@var{pattern}]
4643 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
4644 is provided, the subset of generations that match @var{pattern}.
4645 The syntax of @var{pattern} is the same as with @code{guix package
4646 --list-generations} (@pxref{Invoking guix package}).
4648 By default, this prints information about the channels used in each
4649 revision as well as the corresponding news entries. If you pass
4650 @option{--details}, it will also print the list of packages added and
4651 upgraded in each generation compared to the previous one.
4654 Instruct @option{--list-generations} or @option{--news} to display more
4655 information about the differences between subsequent generations---see
4659 @cindex rolling back
4660 @cindex undoing transactions
4661 @cindex transactions, undoing
4662 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
4663 undo the last transaction.
4665 @item --switch-generation=@var{pattern}
4666 @itemx -S @var{pattern}
4668 Switch to a particular generation defined by @var{pattern}.
4670 @var{pattern} may be either a generation number or a number prefixed
4671 with ``+'' or ``-''. The latter means: move forward/backward by a
4672 specified number of generations. For example, if you want to return to
4673 the latest generation after @option{--roll-back}, use
4674 @option{--switch-generation=+1}.
4676 @item --delete-generations[=@var{pattern}]
4677 @itemx -d [@var{pattern}]
4678 When @var{pattern} is omitted, delete all generations except the current
4681 This command accepts the same patterns as @option{--list-generations}.
4682 When @var{pattern} is specified, delete the matching generations. When
4683 @var{pattern} specifies a duration, generations @emph{older} than the
4684 specified duration match. For instance, @option{--delete-generations=1m}
4685 deletes generations that are more than one month old.
4687 If the current generation matches, it is @emph{not} deleted.
4689 Note that deleting generations prevents rolling back to them.
4690 Consequently, this command must be used with care.
4692 @xref{Invoking guix describe}, for a way to display information about the
4693 current generation only.
4695 @item --profile=@var{profile}
4696 @itemx -p @var{profile}
4697 Use @var{profile} instead of @file{~/.config/guix/current}.
4701 Show which channel commit(s) would be used and what would be built or
4702 substituted but do not actually do it.
4704 @item --allow-downgrades
4705 Allow pulling older or unrelated revisions of channels than those
4708 @cindex downgrade attacks, protection against
4709 By default, @command{guix pull} protects against so-called ``downgrade
4710 attacks'' whereby the Git repository of a channel would be reset to an
4711 earlier or unrelated revision of itself, potentially leading you to
4712 install older, known-vulnerable versions of software packages.
4715 Make sure you understand its security implications before using
4716 @option{--allow-downgrades}.
4719 @item --disable-authentication
4720 Allow pulling channel code without authenticating it.
4722 @cindex authentication, of channel code
4723 By default, @command{guix pull} authenticates code downloaded from
4724 channels by verifying that its commits are signed by authorized
4725 developers, and raises an error if this is not the case. This option
4726 instructs it to not perform any such verification.
4729 Make sure you understand its security implications before using
4730 @option{--disable-authentication}.
4733 @item --system=@var{system}
4734 @itemx -s @var{system}
4735 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4736 the system type of the build host.
4739 Use the bootstrap Guile to build the latest Guix. This option is only
4740 useful to Guix developers.
4743 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
4744 repository and branch to pull from, as well as @emph{additional} repositories
4745 containing package modules that should be deployed. @xref{Channels}, for more
4748 In addition, @command{guix pull} supports all the common build options
4749 (@pxref{Common Build Options}).
4751 @node Invoking guix time-machine
4752 @section Invoking @command{guix time-machine}
4754 @cindex @command{guix time-machine}
4755 @cindex pinning, channels
4756 @cindex replicating Guix
4757 @cindex reproducibility, of Guix
4759 The @command{guix time-machine} command provides access to other
4760 revisions of Guix, for example to install older versions of packages,
4761 or to reproduce a computation in an identical environment. The revision
4762 of Guix to be used is defined by a commit or by a channel
4763 description file created by @command{guix describe}
4764 (@pxref{Invoking guix describe}).
4766 The general syntax is:
4769 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4772 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4773 @command{guix} command of the specified revision. The @var{options} that define
4774 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4777 @item --url=@var{url}
4778 @itemx --commit=@var{commit}
4779 @itemx --branch=@var{branch}
4780 Use the @code{guix} channel from the specified @var{url}, at the
4781 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4782 string), or @var{branch}.
4784 @item --channels=@var{file}
4785 @itemx -C @var{file}
4786 Read the list of channels from @var{file}. @var{file} must contain
4787 Scheme code that evaluates to a list of channel objects.
4788 @xref{Channels} for more information.
4791 As for @command{guix pull}, the absence of any options means that the
4792 latest commit on the master branch will be used. The command
4795 guix time-machine -- build hello
4798 will thus build the package @code{hello} as defined in the master branch,
4799 which is in general a newer revision of Guix than you have installed.
4800 Time travel works in both directions!
4802 Note that @command{guix time-machine} can trigger builds of channels and
4803 their dependencies, and these are controlled by the standard build
4804 options (@pxref{Common Build Options}).
4809 @c TODO: Remove this once we're more confident about API stability.
4811 The functionality described here is a ``technology preview'' as of version
4812 @value{VERSION}. As such, the interface is subject to change.
4816 @cindex composition of Guix revisions
4817 Sometimes you might need to mix packages from the revision of Guix you're
4818 currently running with packages available in a different revision of Guix.
4819 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4820 revisions in arbitrary ways.
4822 @cindex inferior packages
4823 Technically, an ``inferior'' is essentially a separate Guix process connected
4824 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4825 @code{(guix inferior)} module allows you to create inferiors and to
4826 communicate with them. It also provides a high-level interface to browse and
4827 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4829 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4830 to interact with a separate revision of Guix. For example, let's assume you
4831 want to install in your profile the current @code{guile} package, along with
4832 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4833 because the newer @code{guile-json} has an incompatible API and you want to
4834 run your code against the old API@. To do that, you could write a manifest for
4835 use by @code{guix package --manifest} (@pxref{Writing Manifests}); in that
4836 manifest, you would create an inferior for that old Guix revision you care
4837 about, and you would look up the @code{guile-json} package in the inferior:
4840 (use-modules (guix inferior) (guix channels)
4841 (srfi srfi-1)) ;for 'first'
4844 ;; This is the old revision from which we want to
4845 ;; extract guile-json.
4848 (url "https://git.savannah.gnu.org/git/guix.git")
4850 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4853 ;; An inferior representing the above revision.
4854 (inferior-for-channels channels))
4856 ;; Now create a manifest with the current "guile" package
4857 ;; and the old "guile-json" package.
4859 (list (first (lookup-inferior-packages inferior "guile-json"))
4860 (specification->package "guile")))
4863 On its first run, @command{guix package --manifest} might have to build the
4864 channel you specified before it can create the inferior; subsequent runs will
4865 be much faster because the Guix revision will be cached.
4867 The @code{(guix inferior)} module provides the following procedures to open an
4870 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4871 [#:cache-directory] [#:ttl]
4872 Return an inferior for @var{channels}, a list of channels. Use the cache at
4873 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4874 This procedure opens a new connection to the build daemon.
4876 As a side effect, this procedure may build or substitute binaries for
4877 @var{channels}, which can take time.
4880 @deffn {Scheme Procedure} open-inferior @var{directory} @
4881 [#:command "bin/guix"]
4882 Open the inferior Guix in @var{directory}, running
4883 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4884 the inferior could not be launched.
4887 @cindex inferior packages
4888 The procedures listed below allow you to obtain and manipulate inferior
4891 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4892 Return the list of packages known to @var{inferior}.
4895 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4897 Return the sorted list of inferior packages matching @var{name} in
4898 @var{inferior}, with highest version numbers first. If @var{version} is true,
4899 return only packages with a version number prefixed by @var{version}.
4902 @deffn {Scheme Procedure} inferior-package? @var{obj}
4903 Return true if @var{obj} is an inferior package.
4906 @deffn {Scheme Procedure} inferior-package-name @var{package}
4907 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4908 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4909 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4910 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4911 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4912 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4913 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4914 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4915 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4916 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4917 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4918 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4919 These procedures are the counterpart of package record accessors
4920 (@pxref{package Reference}). Most of them work by querying the inferior
4921 @var{package} comes from, so the inferior must still be live when you call
4925 Inferior packages can be used transparently like any other package or
4926 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4927 transparently handled by the @code{packages->manifest} procedure, which is
4928 commonly used in manifests (@pxref{Invoking guix package, the
4929 @option{--manifest} option of @command{guix package}}). Thus you can insert
4930 an inferior package pretty much anywhere you would insert a regular package:
4931 in manifests, in the @code{packages} field of your @code{operating-system}
4932 declaration, and so on.
4934 @node Invoking guix describe
4935 @section Invoking @command{guix describe}
4937 @cindex reproducibility
4938 @cindex replicating Guix
4939 Often you may want to answer questions like: ``Which revision of Guix am I
4940 using?'' or ``Which channels am I using?'' This is useful information in many
4941 situations: if you want to @emph{replicate} an environment on a different
4942 machine or user account, if you want to report a bug or to determine what
4943 change in the channels you are using caused it, or if you want to record your
4944 system state for reproducibility purposes. The @command{guix describe}
4945 command answers these questions.
4947 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4948 displays the channel(s) that it was built from, including their repository URL
4949 and commit IDs (@pxref{Channels}):
4953 Generation 10 Sep 03 2018 17:32:44 (current)
4955 repository URL: https://git.savannah.gnu.org/git/guix.git
4957 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4960 If you're familiar with the Git version control system, this is similar in
4961 spirit to @command{git describe}; the output is also similar to that of
4962 @command{guix pull --list-generations}, but limited to the current generation
4963 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4964 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4965 information is all it takes to describe the revision of Guix you're using, and
4966 also to replicate it.
4968 To make it easier to replicate Guix, @command{guix describe} can also be asked
4969 to return a list of channels instead of the human-readable description above:
4972 $ guix describe -f channels
4975 (url "https://git.savannah.gnu.org/git/guix.git")
4977 "e0fa68c7718fffd33d81af415279d6ddb518f727")
4979 (make-channel-introduction
4980 "9edb3f66fd807b096b48283debdcddccfea34bad"
4981 (openpgp-fingerprint
4982 "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
4986 You can save this to a file and feed it to @command{guix pull -C} on some
4987 other machine or at a later point in time, which will instantiate @emph{this
4988 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4989 From there on, since you're able to deploy the same revision of Guix, you can
4990 just as well @emph{replicate a complete software environment}. We humbly
4991 think that this is @emph{awesome}, and we hope you'll like it too!
4993 The details of the options supported by @command{guix describe} are as
4997 @item --format=@var{format}
4998 @itemx -f @var{format}
4999 Produce output in the specified @var{format}, one of:
5003 produce human-readable output;
5005 produce a list of channel specifications that can be passed to @command{guix
5006 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
5008 @item channels-sans-intro
5009 like @code{channels}, but omit the @code{introduction} field; use it to
5010 produce a channel specification suitable for Guix version 1.1.0 or
5011 earlier---the @code{introduction} field has to do with channel
5012 authentication (@pxref{Channels, Channel Authentication}) and is not
5013 supported by these older versions;
5016 produce a list of channel specifications in JSON format;
5018 produce a list of channel specifications in Recutils format.
5021 @item --list-formats
5022 Display available formats for @option{--format} option.
5024 @item --profile=@var{profile}
5025 @itemx -p @var{profile}
5026 Display information about @var{profile}.
5029 @node Invoking guix archive
5030 @section Invoking @command{guix archive}
5032 @cindex @command{guix archive}
5034 The @command{guix archive} command allows users to @dfn{export} files
5035 from the store into a single archive, and to later @dfn{import} them on
5036 a machine that runs Guix.
5037 In particular, it allows store files to be transferred from one machine
5038 to the store on another machine.
5041 If you're looking for a way to produce archives in a format suitable for
5042 tools other than Guix, @pxref{Invoking guix pack}.
5045 @cindex exporting store items
5046 To export store files as an archive to standard output, run:
5049 guix archive --export @var{options} @var{specifications}...
5052 @var{specifications} may be either store file names or package
5053 specifications, as for @command{guix package} (@pxref{Invoking guix
5054 package}). For instance, the following command creates an archive
5055 containing the @code{gui} output of the @code{git} package and the main
5056 output of @code{emacs}:
5059 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
5062 If the specified packages are not built yet, @command{guix archive}
5063 automatically builds them. The build process may be controlled with the
5064 common build options (@pxref{Common Build Options}).
5066 To transfer the @code{emacs} package to a machine connected over SSH,
5070 guix archive --export -r emacs | ssh the-machine guix archive --import
5074 Similarly, a complete user profile may be transferred from one machine
5075 to another like this:
5078 guix archive --export -r $(readlink -f ~/.guix-profile) | \
5079 ssh the-machine guix archive --import
5083 However, note that, in both examples, all of @code{emacs} and the
5084 profile as well as all of their dependencies are transferred (due to
5085 @option{-r}), regardless of what is already available in the store on
5086 the target machine. The @option{--missing} option can help figure out
5087 which items are missing from the target store. The @command{guix copy}
5088 command simplifies and optimizes this whole process, so this is probably
5089 what you should use in this case (@pxref{Invoking guix copy}).
5091 @cindex nar, archive format
5092 @cindex normalized archive (nar)
5093 @cindex nar bundle, archive format
5094 Each store item is written in the @dfn{normalized archive} or @dfn{nar}
5095 format (described below), and the output of @command{guix archive
5096 --export} (and input of @command{guix archive --import}) is a @dfn{nar
5100 comparable in spirit to `tar', but with differences
5101 that make it more appropriate for our purposes. First, rather than
5102 recording all Unix metadata for each file, the nar format only mentions
5103 the file type (regular, directory, or symbolic link); Unix permissions
5104 and owner/group are dismissed. Second, the order in which directory
5105 entries are stored always follows the order of file names according to
5106 the C locale collation order. This makes archive production fully
5109 That nar bundle format is essentially the concatenation of zero or more
5110 nars along with metadata for each store item it contains: its file name,
5111 references, corresponding derivation, and a digital signature.
5113 When exporting, the daemon digitally signs the contents of the archive,
5114 and that digital signature is appended. When importing, the daemon
5115 verifies the signature and rejects the import in case of an invalid
5116 signature or if the signing key is not authorized.
5117 @c FIXME: Add xref to daemon doc about signatures.
5119 The main options are:
5123 Export the specified store files or packages (see below). Write the
5124 resulting archive to the standard output.
5126 Dependencies are @emph{not} included in the output, unless
5127 @option{--recursive} is passed.
5131 When combined with @option{--export}, this instructs @command{guix archive}
5132 to include dependencies of the given items in the archive. Thus, the
5133 resulting archive is self-contained: it contains the closure of the
5134 exported store items.
5137 Read an archive from the standard input, and import the files listed
5138 therein into the store. Abort if the archive has an invalid digital
5139 signature, or if it is signed by a public key not among the authorized
5140 keys (see @option{--authorize} below).
5143 Read a list of store file names from the standard input, one per line,
5144 and write on the standard output the subset of these files missing from
5147 @item --generate-key[=@var{parameters}]
5148 @cindex signing, archives
5149 Generate a new key pair for the daemon. This is a prerequisite before
5150 archives can be exported with @option{--export}. This
5151 operation is usually instantaneous but it can take time if the system's
5152 entropy pool needs to be refilled. On Guix System,
5153 @code{guix-service-type} takes care of generating this key pair the
5156 The generated key pair is typically stored under @file{/etc/guix}, in
5157 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
5158 key, which must be kept secret). When @var{parameters} is omitted,
5159 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
5160 versions before 1.6.0, it is a 4096-bit RSA key.
5161 Alternatively, @var{parameters} can specify
5162 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
5163 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
5164 Libgcrypt Reference Manual}).
5167 @cindex authorizing, archives
5168 Authorize imports signed by the public key passed on standard input.
5169 The public key must be in ``s-expression advanced format''---i.e., the
5170 same format as the @file{signing-key.pub} file.
5172 The list of authorized keys is kept in the human-editable file
5173 @file{/etc/guix/acl}. The file contains
5174 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
5175 s-expressions''} and is structured as an access-control list in the
5176 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
5179 @item --extract=@var{directory}
5180 @itemx -x @var{directory}
5181 Read a single-item archive as served by substitute servers
5182 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
5183 low-level operation needed in only very narrow use cases; see below.
5185 For example, the following command extracts the substitute for Emacs
5186 served by @code{@value{SUBSTITUTE-SERVER-1}} to @file{/tmp/emacs}:
5190 https://@value{SUBSTITUTE-SERVER-1}/nar/gzip/@dots{}-emacs-24.5 \
5191 | gunzip | guix archive -x /tmp/emacs
5194 Single-item archives are different from multiple-item archives produced
5195 by @command{guix archive --export}; they contain a single store item,
5196 and they do @emph{not} embed a signature. Thus this operation does
5197 @emph{no} signature verification and its output should be considered
5200 The primary purpose of this operation is to facilitate inspection of
5201 archive contents coming from possibly untrusted substitute servers
5202 (@pxref{Invoking guix challenge}).
5206 Read a single-item archive as served by substitute servers
5207 (@pxref{Substitutes}) and print the list of files it contains, as in
5212 https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-emacs-26.3 \
5213 | lzip -d | guix archive -t
5218 @c *********************************************************************
5223 @cindex @file{channels.scm}, configuration file
5224 @cindex configuration file for channels
5225 @cindex @command{guix pull}, configuration file
5226 @cindex configuration of @command{guix pull}
5227 Guix and its package collection are updated by running @command{guix pull}
5228 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
5229 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
5230 customized by defining @dfn{channels} in the
5231 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
5232 of a Git repository to be deployed, and @command{guix pull} can be instructed
5233 to pull from one or more channels. In other words, channels can be used
5234 to @emph{customize} and to @emph{extend} Guix, as we will see below.
5235 Guix is able to take into account security concerns and deal with authenticated
5239 * Specifying Additional Channels:: Extending the package collection.
5240 * Using a Custom Guix Channel:: Using a customized Guix.
5241 * Replicating Guix:: Running the @emph{exact same} Guix.
5242 * Channel Authentication:: How Guix verifies what it fetches.
5243 * Channels with Substitutes:: Using channels with available substitutes.
5244 * Creating a Channel:: How to write your custom channel.
5245 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
5246 * Declaring Channel Dependencies:: How to depend on other channels.
5247 * Specifying Channel Authorizations:: Defining channel authors authorizations.
5248 * Primary URL:: Distinguishing mirror to original.
5249 * Writing Channel News:: Communicating information to channel's users.
5252 @node Specifying Additional Channels
5253 @section Specifying Additional Channels
5255 @cindex extending the package collection (channels)
5256 @cindex variant packages (channels)
5257 You can specify @emph{additional channels} to pull from. To use a channel, write
5258 @code{~/.config/guix/channels.scm} to instruct @command{guix pull} to pull from it
5259 @emph{in addition} to the default Guix channel(s):
5261 @vindex %default-channels
5263 ;; Add variant packages to those Guix provides.
5265 (name 'variant-packages)
5266 (url "https://example.org/variant-packages.git"))
5271 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
5272 add a channel the list of channels that the variable @code{%default-channels}
5273 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
5274 Manual}). With this file in place, @command{guix pull} builds not only Guix
5275 but also the package modules from your own repository. The result in
5276 @file{~/.config/guix/current} is the union of Guix with your own package
5281 Generation 19 Aug 27 2018 16:20:48
5283 repository URL: https://git.savannah.gnu.org/git/guix.git
5285 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
5286 variant-packages dd3df5e
5287 repository URL: https://example.org/variant-packages.git
5289 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
5293 The output of @command{guix describe} above shows that we're now running
5294 Generation@tie{}19 and that it includes
5295 both Guix and packages from the @code{variant-personal-packages} channel
5296 (@pxref{Invoking guix describe}).
5298 @node Using a Custom Guix Channel
5299 @section Using a Custom Guix Channel
5301 The channel called @code{guix} specifies where Guix itself---its command-line
5302 tools as well as its package collection---should be downloaded. For instance,
5303 suppose you want to update from another copy of the Guix repository at
5304 @code{example.org}, and specifically the @code{super-hacks} branch, you can
5305 write in @code{~/.config/guix/channels.scm} this specification:
5308 ;; Tell 'guix pull' to use another repo.
5311 (url "https://example.org/another-guix.git")
5312 (branch "super-hacks")))
5316 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
5317 branch of the repository at @code{example.org}. The authentication concern is
5318 addressed below (@pxref{Channel Authentication}).
5320 @node Replicating Guix
5321 @section Replicating Guix
5323 @cindex pinning, channels
5324 @cindex replicating Guix
5325 @cindex reproducibility, of Guix
5326 The @command{guix describe} command shows precisely which commits were
5327 used to build the instance of Guix we're using (@pxref{Invoking guix
5328 describe}). We can replicate this instance on another machine or at a
5329 different point in time by providing a channel specification ``pinned''
5330 to these commits that looks like this:
5333 ;; Deploy specific commits of my channels of interest.
5336 (url "https://git.savannah.gnu.org/git/guix.git")
5337 (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
5339 (name 'variant-packages)
5340 (url "https://example.org/variant-packages.git")
5341 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
5344 To obtain this pinned channel specification, the easiest way is to run
5345 @command{guix describe} and to save its output in the @code{channels}
5346 format in a file, like so:
5349 guix describe -f channels > channels.scm
5352 The resulting @file{channels.scm} file can be passed to the @option{-C}
5353 option of @command{guix pull} (@pxref{Invoking guix pull}) or
5354 @command{guix time-machine} (@pxref{Invoking guix time-machine}), as in
5358 guix time-machine -C channels.scm -- shell python -- python3
5361 Given the @file{channels.scm} file, the command above will always fetch
5362 the @emph{exact same Guix instance}, then use that instance to run the
5363 exact same Python (@pxref{Invoking guix shell}). On any machine, at any
5364 time, it ends up running the exact same binaries, bit for bit.
5367 Pinned channels address a problem similar to ``lock files'' as
5368 implemented by some deployment tools---they let you pin and reproduce a
5369 set of packages. In the case of Guix though, you are effectively
5370 pinning the entire package set as defined at the given channel commits;
5371 in fact, you are pinning all of Guix, including its core modules and
5372 command-line tools. You're also getting strong guarantees that you are,
5373 indeed, obtaining the exact same software.
5375 This gives you super powers, allowing you to track the provenance of binary
5376 artifacts with very fine grain, and to reproduce software environments at
5377 will---some sort of ``meta reproducibility'' capabilities, if you will.
5378 @xref{Inferiors}, for another way to take advantage of these super powers.
5380 @node Channel Authentication
5381 @section Channel Authentication
5383 @anchor{channel-authentication}
5384 @cindex authentication, of channel code
5385 The @command{guix pull} and @command{guix time-machine} commands
5386 @dfn{authenticate} the code retrieved from channels: they make sure each
5387 commit that is fetched is signed by an authorized developer. The goal
5388 is to protect from unauthorized modifications to the channel that would
5389 lead users to run malicious code.
5391 As a user, you must provide a @dfn{channel introduction} in your
5392 channels file so that Guix knows how to authenticate its first commit.
5393 A channel specification, including its introduction, looks something
5398 (name 'some-channel)
5399 (url "https://example.org/some-channel.git")
5401 (make-channel-introduction
5402 "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
5403 (openpgp-fingerprint
5404 "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5407 The specification above shows the name and URL of the channel. The call
5408 to @code{make-channel-introduction} above specifies that authentication
5409 of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
5410 by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
5412 For the main channel, called @code{guix}, you automatically get that
5413 information from your Guix installation. For other channels, include
5414 the channel introduction provided by the channel authors in your
5415 @file{channels.scm} file. Make sure you retrieve the channel
5416 introduction from a trusted source since that is the root of your trust.
5418 If you're curious about the authentication mechanics, read on!
5420 @node Channels with Substitutes
5421 @section Channels with Substitutes
5423 When running @command{guix pull}, Guix will first compile the
5424 definitions of every available package. This is an expensive operation
5425 for which substitutes (@pxref{Substitutes}) may be available. The
5426 following snippet in @file{channels.scm} will ensure that @command{guix
5427 pull} uses the latest commit with available substitutes for the package
5428 definitions: this is done by querying the continuous integration
5429 server at @url{https://ci.guix.gnu.org}.
5432 (use-modules (guix ci))
5434 (list (channel-with-substitutes-available
5435 %default-guix-channel
5436 "https://ci.guix.gnu.org"))
5439 Note that this does not mean that all the packages that you will
5440 install after running @command{guix pull} will have available
5441 substitutes. It only ensures that @command{guix pull} will not try to
5442 compile package definitions. This is particularly useful when using
5443 machines with limited resources.
5445 @node Creating a Channel
5446 @section Creating a Channel
5448 @cindex personal packages (channels)
5449 @cindex channels, for personal packages
5450 Let's say you have a bunch of custom package variants or personal packages
5451 that you think would make little sense to contribute to the Guix project, but
5452 would like to have these packages transparently available to you at the
5453 command line. You would first write modules containing those package
5454 definitions (@pxref{Package Modules}), maintain them in a Git repository, and
5455 then you and anyone else can use it as an additional channel to get packages
5458 @c What follows stems from discussions at
5459 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
5460 @c earlier discussions on guix-devel@gnu.org.
5462 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
5463 publish your personal channel to the world, we would like to share a few words
5468 Before publishing a channel, please consider contributing your package
5469 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
5470 to free software of all sorts, and packages in Guix proper are readily
5471 available to all Guix users and benefit from the project's quality assurance
5475 When you maintain package definitions outside Guix, we, Guix developers,
5476 consider that @emph{the compatibility burden is on you}. Remember that
5477 package modules and package definitions are just Scheme code that uses various
5478 programming interfaces (APIs). We want to remain free to change these APIs to
5479 keep improving Guix, possibly in ways that break your channel. We never
5480 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
5484 Corollary: if you're using an external channel and that channel breaks, please
5485 @emph{report the issue to the channel authors}, not to the Guix project.
5488 You've been warned! Having said this, we believe external channels are a
5489 practical way to exert your freedom to augment Guix' package collection and to
5490 share your improvements, which are basic tenets of
5491 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
5492 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
5495 To create a channel, create a Git repository containing your own package
5496 modules and make it available. The repository can contain anything, but a
5497 useful channel will contain Guile modules that export packages. Once you
5498 start using a channel, Guix will behave as if the root directory of that
5499 channel's Git repository has been added to the Guile load path (@pxref{Load
5500 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
5501 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
5502 module, then the module will be available under the name @code{(my-packages
5503 my-tools)}, and you will be able to use it like any other module
5504 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
5506 As a channel author, consider bundling authentication material with your
5507 channel so that users can authenticate it. @xref{Channel
5508 Authentication}, and @ref{Specifying Channel Authorizations}, for info
5512 @node Package Modules in a Sub-directory
5513 @section Package Modules in a Sub-directory
5515 @cindex subdirectory, channels
5516 As a channel author, you may want to keep your channel modules in a
5517 sub-directory. If your modules are in the sub-directory @file{guix}, you must
5518 add a meta-data file @file{.guix-channel} that contains:
5526 @node Declaring Channel Dependencies
5527 @section Declaring Channel Dependencies
5529 @cindex dependencies, channels
5530 @cindex meta-data, channels
5531 Channel authors may decide to augment a package collection provided by other
5532 channels. They can declare their channel to be dependent on other channels in
5533 a meta-data file @file{.guix-channel}, which is to be placed in the root of
5534 the channel repository.
5536 The meta-data file should contain a simple S-expression like this:
5543 (name some-collection)
5544 (url "https://example.org/first-collection.git")
5546 ;; The 'introduction' bit below is optional: you would
5547 ;; provide it for dependencies that can be authenticated.
5549 (channel-introduction
5551 (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
5552 (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5554 (name some-other-collection)
5555 (url "https://example.org/second-collection.git")
5556 (branch "testing"))))
5559 In the above example this channel is declared to depend on two other channels,
5560 which will both be fetched automatically. The modules provided by the channel
5561 will be compiled in an environment where the modules of all these declared
5562 channels are available.
5564 For the sake of reliability and maintainability, you should avoid dependencies
5565 on channels that you don't control, and you should aim to keep the number of
5566 dependencies to a minimum.
5568 @node Specifying Channel Authorizations
5569 @section Specifying Channel Authorizations
5571 @cindex channel authorizations
5572 @anchor{channel-authorizations}
5573 As we saw above, Guix ensures the source code it pulls from channels
5574 comes from authorized developers. As a channel author, you need to
5575 specify the list of authorized developers in the
5576 @file{.guix-authorizations} file in the channel's Git repository. The
5577 authentication rule is simple: each commit must be signed by a key
5578 listed in the @file{.guix-authorizations} file of its parent
5579 commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
5580 (DAG). Each commit can have zero or more parents; ``regular'' commits
5581 have one parent and merge commits have two parent commits. Read
5582 @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
5583 for Computer Scientists}} for a great overview.} The
5584 @file{.guix-authorizations} file looks like this:
5587 ;; Example '.guix-authorizations' file.
5590 (version 0) ;current file format version
5592 (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
5594 ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
5596 ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
5600 Each fingerprint is followed by optional key/value pairs, as in the
5601 example above. Currently these key/value pairs are ignored.
5603 This authentication rule creates a chicken-and-egg issue: how do we
5604 authenticate the first commit? Related to that: how do we deal with
5605 channels whose repository history contains unsigned commits and lack
5606 @file{.guix-authorizations}? And how do we fork existing channels?
5608 @cindex channel introduction
5609 Channel introductions answer these questions by describing the first
5610 commit of a channel that should be authenticated. The first time a
5611 channel is fetched with @command{guix pull} or @command{guix
5612 time-machine}, the command looks up the introductory commit and verifies
5613 that it is signed by the specified OpenPGP key. From then on, it
5614 authenticates commits according to the rule above. Authentication fails
5615 if the target commit is neither a descendant nor an ancestor of the
5616 introductory commit.
5618 Additionally, your channel must provide all the OpenPGP keys that were
5619 ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
5620 files, which can be either binary or ``ASCII-armored''. By default,
5621 those @file{.key} files are searched for in the branch named
5622 @code{keyring} but you can specify a different branch name in
5623 @code{.guix-channel} like so:
5628 (keyring-reference "my-keyring-branch"))
5631 To summarize, as the author of a channel, there are three things you have
5632 to do to allow users to authenticate your code:
5636 Export the OpenPGP keys of past and present committers with @command{gpg
5637 --export} and store them in @file{.key} files, by default in a branch
5638 named @code{keyring} (we recommend making it an @dfn{orphan branch}).
5641 Introduce an initial @file{.guix-authorizations} in the channel's
5642 repository. Do that in a signed commit (@pxref{Commit Access}, for
5643 information on how to sign Git commits.)
5646 Advertise the channel introduction, for instance on your channel's web
5647 page. The channel introduction, as we saw above, is the commit/key
5648 pair---i.e., the commit that introduced @file{.guix-authorizations}, and
5649 the fingerprint of the OpenPGP used to sign it.
5652 Before pushing to your public Git repository, you can run @command{guix
5653 git-authenticate} to verify that you did sign all the commits you are
5654 about to push with an authorized key:
5657 guix git authenticate @var{commit} @var{signer}
5661 where @var{commit} and @var{signer} are your channel introduction.
5662 @xref{Invoking guix git authenticate}, for details.
5664 Publishing a signed channel requires discipline: any mistake, such as an
5665 unsigned commit or a commit signed by an unauthorized key, will prevent
5666 users from pulling from your channel---well, that's the whole point of
5667 authentication! Pay attention to merges in particular: merge commits
5668 are considered authentic if and only if they are signed by a key present
5669 in the @file{.guix-authorizations} file of @emph{both} branches.
5672 @section Primary URL
5674 @cindex primary URL, channels
5675 Channel authors can indicate the primary URL of their channel's Git
5676 repository in the @file{.guix-channel} file, like so:
5681 (url "https://example.org/guix.git"))
5684 This allows @command{guix pull} to determine whether it is pulling code
5685 from a mirror of the channel; when that is the case, it warns the user
5686 that the mirror might be stale and displays the primary URL@. That way,
5687 users cannot be tricked into fetching code from a stale mirror that does
5688 not receive security updates.
5690 This feature only makes sense for authenticated repositories, such as
5691 the official @code{guix} channel, for which @command{guix pull} ensures
5692 the code it fetches is authentic.
5694 @node Writing Channel News
5695 @section Writing Channel News
5697 @cindex news, for channels
5698 Channel authors may occasionally want to communicate to their users
5699 information about important changes in the channel. You'd send them all
5700 an email, but that's not convenient.
5702 Instead, channels can provide a @dfn{news file}; when the channel users
5703 run @command{guix pull}, that news file is automatically read and
5704 @command{guix pull --news} can display the announcements that correspond
5705 to the new commits that have been pulled, if any.
5707 To do that, channel authors must first declare the name of the news file
5708 in their @file{.guix-channel} file:
5713 (news-file "etc/news.txt"))
5716 The news file itself, @file{etc/news.txt} in this example, must look
5717 something like this:
5722 (entry (tag "the-bug-fix")
5723 (title (en "Fixed terrible bug")
5725 (body (en "@@emph@{Good news@}! It's fixed!")
5726 (eo "Certe ĝi pli bone funkcias nun!")))
5727 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
5728 (title (en "Added a great package")
5729 (ca "Què vol dir guix?"))
5730 (body (en "Don't miss the @@code@{hello@} package!"))))
5733 While the news file is using the Scheme syntax, avoid naming it with a
5734 @file{.scm} extension or else it will get picked up when building the
5735 channel and yield an error since it is not a valid module.
5736 Alternatively, you can move the channel module to a subdirectory and
5737 store the news file in another directory.
5739 The file consists of a list of @dfn{news entries}. Each entry is
5740 associated with a commit or tag: it describes changes made in this
5741 commit, possibly in preceding commits as well. Users see entries only
5742 the first time they obtain the commit the entry refers to.
5744 The @code{title} field should be a one-line summary while @code{body}
5745 can be arbitrarily long, and both can contain Texinfo markup
5746 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
5747 a list of language tag/message tuples, which allows @command{guix pull}
5748 to display news in the language that corresponds to the user's locale.
5750 If you want to translate news using a gettext-based workflow, you can
5751 extract translatable strings with @command{xgettext} (@pxref{xgettext
5752 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
5753 you write news entries in English first, the command below creates a PO
5754 file containing the strings to translate:
5757 xgettext -o news.po -l scheme -ken etc/news.txt
5760 To sum up, yes, you could use your channel as a blog. But beware, this
5761 is @emph{not quite} what your users might expect.
5763 @c *********************************************************************
5765 @chapter Development
5767 @cindex software development
5768 If you are a software developer, Guix provides tools that you should find
5769 helpful---independently of the language you're developing in. This is what
5770 this chapter is about.
5772 The @command{guix shell} command provides a convenient way to set up
5773 one-off software environments, be it for development purposes or to run
5774 a command without installing it in your profile. The @command{guix
5775 pack} command allows you to create @dfn{application bundles} that can be
5776 easily distributed to users who do not run Guix.
5779 * Invoking guix shell:: Spawning one-off software environments.
5780 * Invoking guix environment:: Setting up development environments.
5781 * Invoking guix pack:: Creating software bundles.
5782 * The GCC toolchain:: Working with languages supported by GCC.
5783 * Invoking guix git authenticate:: Authenticating Git repositories.
5786 @node Invoking guix shell
5787 @section Invoking @command{guix shell}
5789 @cindex reproducible build environments
5790 @cindex development environments
5791 @cindex @command{guix environment}
5792 @cindex environment, package build environment
5793 The purpose of @command{guix shell} is to make it easy to create one-off
5794 software environments, without changing one's profile. It is typically
5795 used to create development environments; it is also a convenient way to
5796 run applications without ``polluting'' your profile.
5799 The @command{guix shell} command was recently introduced to supersede
5800 @command{guix environment} (@pxref{Invoking guix environment}). If you
5801 are familiar with @command{guix environment}, you will notice that it is
5802 similar but also---we hope!---more convenient.
5805 The general syntax is:
5808 guix shell [@var{options}] [@var{package}@dots{}]
5811 The following example creates an environment containing Python and NumPy,
5812 building or downloading any missing package, and runs the
5813 @command{python3} command in that environment:
5816 guix shell python python-numpy -- python3
5819 Development environments can be created as in the example below, which
5820 spawns an interactive shell containing all the dependencies and
5821 environment variables needed to work on Inkscape:
5824 guix shell --development inkscape
5827 Exiting the shell places the user back in the original environment
5828 before @command{guix shell} was invoked. The next garbage collection
5829 (@pxref{Invoking guix gc}) may clean up packages that were installed in
5830 the environment and that are no longer used outside of it.
5832 As an added convenience, @command{guix shell} will try to do what you
5833 mean when it is invoked interactively without any other arguments
5840 If it finds a @file{manifest.scm} in the current working directory or
5841 any of its parents, it uses this manifest as though it was given via @code{--manifest}.
5842 Likewise, if it finds a @file{guix.scm} in the same directories, it uses
5843 it to build a development profile as though both @code{--development}
5844 and @code{--file} were present.
5845 In either case, the file will only be loaded if the directory it
5846 resides in is listed in
5847 @file{~/.config/guix/shell-authorized-directories}.
5848 This provides an easy way to define, share, and enter development
5851 By default, the shell session or command runs in an @emph{augmented}
5852 environment, where the new packages are added to search path environment
5853 variables such as @code{PATH}. You can, instead, choose to create an
5854 @emph{isolated} environment containing nothing but the packages you
5855 asked for. Passing the @option{--pure} option clears environment
5856 variable definitions found in the parent environment@footnote{Be sure to
5857 use the @option{--check} option the first time you use @command{guix
5858 shell} interactively to make sure the shell does not undo the effect of
5859 @option{--pure}.}; passing @option{--container} goes one step further by
5860 spawning a @dfn{container} isolated from the rest of the system:
5863 guix shell --container emacs gcc-toolchain
5866 The command above spawns an interactive shell in a container where
5867 nothing but @code{emacs}, @code{gcc-toolchain}, and their dependencies
5868 is available. The container lacks network access and shares no files
5869 other than the current working directory with the surrounding
5870 environment. This is useful to prevent access to system-wide resources
5871 such as @file{/usr/bin} on foreign distros.
5873 This @option{--container} option can also prove useful if you wish to
5874 run a security-sensitive application, such as a web browser, in an
5875 isolated environment. For example, the command below launches
5876 Ungoogled-Chromium in an isolated environment, this time sharing network
5877 access with the host and preserving its @code{DISPLAY} environment
5878 variable, but without even sharing the current directory:
5881 guix shell --container --network --no-cwd ungoogled-chromium \
5882 --preserve='^DISPLAY$' -- chromium
5885 @vindex GUIX_ENVIRONMENT
5886 @command{guix shell} defines the @env{GUIX_ENVIRONMENT}
5887 variable in the shell it spawns; its value is the file name of the
5888 profile of this environment. This allows users to, say, define a
5889 specific prompt for development environments in their @file{.bashrc}
5890 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
5893 if [ -n "$GUIX_ENVIRONMENT" ]
5895 export PS1="\u@@\h \w [dev]\$ "
5900 ...@: or to browse the profile:
5903 $ ls "$GUIX_ENVIRONMENT/bin"
5906 The available options are summarized below.
5910 Set up the environment and check whether the shell would clobber
5911 environment variables. It's a good idea to use this option the first
5912 time you run @command{guix shell} for an interactive session to make
5913 sure your setup is correct.
5915 For example, if the shell modifies the @env{PATH} environment variable,
5916 report it since you would get a different environment than what you
5919 Such problems usually indicate that the shell startup files are
5920 unexpectedly modifying those environment variables. For example, if you
5921 are using Bash, make sure that environment variables are set or modified
5922 in @file{~/.bash_profile} and @emph{not} in @file{~/.bashrc}---the
5923 former is sourced only by log-in shells. @xref{Bash Startup Files,,,
5924 bash, The GNU Bash Reference Manual}, for details on Bash start-up
5927 @anchor{shell-development-option}
5930 Cause @command{guix shell} to include in the environment the
5931 dependencies of the following package rather than the package itself.
5932 This can be combined with other packages. For instance, the command
5933 below starts an interactive shell containing the build-time dependencies
5934 of GNU@tie{}Guile, plus Autoconf, Automake, and Libtool:
5937 guix shell -D guile autoconf automake libtool
5940 @item --expression=@var{expr}
5941 @itemx -e @var{expr}
5942 Create an environment for the package or list of packages that
5943 @var{expr} evaluates to.
5945 For example, running:
5948 guix shell -D -e '(@@ (gnu packages maths) petsc-openmpi)'
5951 starts a shell with the environment for this specific variant of the
5957 guix shell -e '(@@ (gnu) %base-packages)'
5960 starts a shell with all the base system packages available.
5962 The above commands only use the default output of the given packages.
5963 To select other outputs, two element tuples can be specified:
5966 guix shell -e '(list (@@ (gnu packages bash) bash) "include")'
5969 @xref{package-development-manifest,
5970 @code{package->development-manifest}}, for information on how to write a
5971 manifest for the development environment of a package.
5973 @item --file=@var{file}
5974 @itemx -f @var{file}
5975 Create an environment containing the package or list of packages that
5976 the code within @var{file} evaluates to.
5978 As an example, @var{file} might contain a definition like this
5979 (@pxref{Defining Packages}):
5982 @verbatiminclude environment-gdb.scm
5985 With the file above, you can enter a development environment for GDB by
5989 guix shell -D -f gdb-devel.scm
5992 @anchor{shell-manifest}
5993 @item --manifest=@var{file}
5994 @itemx -m @var{file}
5995 Create an environment for the packages contained in the manifest object
5996 returned by the Scheme code in @var{file}. This option can be repeated
5997 several times, in which case the manifests are concatenated.
5999 This is similar to the same-named option in @command{guix package}
6000 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
6003 @xref{Writing Manifests}, for information on how to write a manifest.
6004 See @option{--export-manifest} below on how to obtain a first manifest.
6006 @cindex manifest, exporting
6007 @anchor{shell-export-manifest}
6008 @item --export-manifest
6009 Write to standard output a manifest suitable for @option{--manifest}
6010 corresponding to given command-line options.
6012 This is a way to ``convert'' command-line arguments into a manifest.
6013 For example, imagine you are tired of typing long lines and would like
6014 to get a manifest equivalent to this command line:
6017 guix shell -D guile git emacs emacs-geiser emacs-geiser-guile
6020 Just add @option{--export-manifest} to the command line above:
6023 guix shell --export-manifest \
6024 -D guile git emacs emacs-geiser emacs-geiser-guile
6028 ... and you get a manifest along these lines:
6031 (concatenate-manifests
6032 (list (specifications->manifest
6036 "emacs-geiser-guile"))
6037 (package->development-manifest
6038 (specification->package "guile"))))
6041 You can store it into a file, say @file{manifest.scm}, and from there
6042 pass it to @command{guix shell} or indeed pretty much any @command{guix}
6046 guix shell -m manifest.scm
6049 Voilà, you've converted a long command line into a manifest! That
6050 conversion process honors package transformation options (@pxref{Package
6051 Transformation Options}) so it should be lossless.
6053 @item --profile=@var{profile}
6054 @itemx -p @var{profile}
6055 Create an environment containing the packages installed in @var{profile}.
6056 Use @command{guix package} (@pxref{Invoking guix package}) to create
6057 and manage profiles.
6060 Unset existing environment variables when building the new environment, except
6061 those specified with @option{--preserve} (see below). This has the effect of
6062 creating an environment in which search paths only contain package inputs.
6064 @item --preserve=@var{regexp}
6065 @itemx -E @var{regexp}
6066 When used alongside @option{--pure}, preserve the environment variables
6067 matching @var{regexp}---in other words, put them on a ``white list'' of
6068 environment variables that must be preserved. This option can be repeated
6072 guix shell --pure --preserve=^SLURM openmpi @dots{} \
6076 This example runs @command{mpirun} in a context where the only environment
6077 variables defined are @env{PATH}, environment variables whose name starts
6078 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
6081 @item --search-paths
6082 Display the environment variable definitions that make up the
6085 @item --system=@var{system}
6086 @itemx -s @var{system}
6087 Attempt to build for @var{system}---e.g., @code{i686-linux}.
6092 Run @var{command} within an isolated container. The current working
6093 directory outside the container is mapped inside the container.
6094 Additionally, unless overridden with @option{--user}, a dummy home
6095 directory is created that matches the current user's home directory, and
6096 @file{/etc/passwd} is configured accordingly.
6098 The spawned process runs as the current user outside the container. Inside
6099 the container, it has the same UID and GID as the current user, unless
6100 @option{--user} is passed (see below).
6104 For containers, share the network namespace with the host system.
6105 Containers created without this flag only have access to the loopback
6108 @item --link-profile
6110 For containers, link the environment profile to @file{~/.guix-profile}
6111 within the container and set @code{GUIX_ENVIRONMENT} to that.
6112 This is equivalent to making @file{~/.guix-profile} a symlink to the
6113 actual profile within the container.
6114 Linking will fail and abort the environment if the directory already
6115 exists, which will certainly be the case if @command{guix shell}
6116 was invoked in the user's home directory.
6118 Certain packages are configured to look in @file{~/.guix-profile} for
6119 configuration files and data;@footnote{For example, the
6120 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
6121 for additional fonts.} @option{--link-profile} allows these programs to
6122 behave as expected within the environment.
6124 @item --user=@var{user}
6125 @itemx -u @var{user}
6126 For containers, use the username @var{user} in place of the current
6127 user. The generated @file{/etc/passwd} entry within the container will
6128 contain the name @var{user}, the home directory will be
6129 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
6130 the UID and GID inside the container are 1000. @var{user}
6131 need not exist on the system.
6133 Additionally, any shared or exposed path (see @option{--share} and
6134 @option{--expose} respectively) whose target is within the current user's
6135 home directory will be remapped relative to @file{/home/USER}; this
6136 includes the automatic mapping of the current working directory.
6139 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
6141 guix shell --container --user=foo \
6142 --expose=$HOME/test \
6143 --expose=/tmp/target=$HOME/target
6146 While this will limit the leaking of user identity through home paths
6147 and each of the user fields, this is only one useful component of a
6148 broader privacy/anonymity solution---not one in and of itself.
6151 For containers, the default behavior is to share the current working
6152 directory with the isolated container and immediately change to that
6153 directory within the container. If this is undesirable,
6154 @option{--no-cwd} will cause the current working directory to @emph{not}
6155 be automatically shared and will change to the user's home directory
6156 within the container instead. See also @option{--user}.
6158 @item --expose=@var{source}[=@var{target}]
6159 @itemx --share=@var{source}[=@var{target}]
6160 For containers, @option{--expose} (resp. @option{--share}) exposes the
6161 file system @var{source} from the host system as the read-only
6162 (resp. writable) file system @var{target} within the container. If
6163 @var{target} is not specified, @var{source} is used as the target mount
6164 point in the container.
6166 The example below spawns a Guile REPL in a container in which the user's
6167 home directory is accessible read-only via the @file{/exchange}
6171 guix shell --container --expose=$HOME=/exchange guile -- guile
6174 @item --rebuild-cache
6175 @cindex caching, of profiles
6176 @cindex caching, in @command{guix shell}
6177 In most cases, @command{guix shell} caches the environment so that
6178 subsequent uses are instantaneous. Least-recently used cache entries
6179 are periodically removed. The cache is also invalidated, when using
6180 @option{--file} or @option{--manifest}, anytime the corresponding file
6183 The @option{--rebuild-cache} forces the cached environment to be
6184 refreshed. This is useful when using @option{--file} or
6185 @option{--manifest} and the @command{guix.scm} or @command{manifest.scm}
6186 file has external dependencies, or if its behavior depends, say, on
6187 environment variables.
6189 @item --root=@var{file}
6190 @itemx -r @var{file}
6191 @cindex persistent environment
6192 @cindex garbage collector root, for environments
6193 Make @var{file} a symlink to the profile for this environment, and
6194 register it as a garbage collector root.
6196 This is useful if you want to protect your environment from garbage
6197 collection, to make it ``persistent''.
6199 When this option is omitted, @command{guix shell} caches profiles so
6200 that subsequent uses of the same environment are instantaneous---this is
6201 comparable to using @option{--root} except that @command{guix shell}
6202 takes care of periodically removing the least-recently used garbage
6205 In some cases, @command{guix shell} does not cache profiles---e.g., if
6206 transformation options such as @option{--with-latest} are used. In
6207 those cases, the environment is protected from garbage collection only
6208 for the duration of the @command{guix shell} session. This means that
6209 next time you recreate the same environment, you could have to rebuild
6210 or re-download packages.
6212 @xref{Invoking guix gc}, for more on GC roots.
6215 @command{guix shell} also supports all of the common build options that
6216 @command{guix build} supports (@pxref{Common Build Options}) as well as
6217 package transformation options (@pxref{Package Transformation Options}).
6219 @node Invoking guix environment
6220 @section Invoking @command{guix environment}
6222 The purpose of @command{guix environment} is to assist in creating
6223 development environments.
6225 @quotation Deprecation warning
6226 The @command{guix environment} command is deprecated in favor of
6227 @command{guix shell}, which performs similar functions but is more
6228 convenient to use. @xref{Invoking guix shell}.
6230 Being deprecated, @command{guix environment} is slated for eventual
6231 removal, but the Guix project is committed to keeping it until May 1st,
6232 2023. Please get in touch with us at @email{guix-devel@@gnu.org} if you
6233 would like to discuss it.
6236 The general syntax is:
6239 guix environment @var{options} @var{package}@dots{}
6242 The following example spawns a new shell set up for the development of
6246 guix environment guile
6249 If the needed dependencies are not built yet, @command{guix environment}
6250 automatically builds them. The environment of the new shell is an
6251 augmented version of the environment that @command{guix environment} was
6252 run in. It contains the necessary search paths for building the given
6253 package added to the existing environment variables. To create
6254 a ``pure'' environment, in which the original environment variables have
6255 been unset, use the @option{--pure} option@footnote{Users sometimes
6256 wrongfully augment environment variables such as @env{PATH} in their
6257 @file{~/.bashrc} file. As a consequence, when @command{guix
6258 environment} launches it, Bash may read @file{~/.bashrc}, thereby
6259 introducing ``impurities'' in these environment variables. It is an
6260 error to define such environment variables in @file{.bashrc}; instead,
6261 they should be defined in @file{.bash_profile}, which is sourced only by
6262 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
6263 Manual}, for details on Bash start-up files.}.
6265 Exiting from a Guix environment is the same as exiting from the shell,
6266 and will place the user back in the old environment before @command{guix
6267 environment} was invoked. The next garbage collection (@pxref{Invoking
6268 guix gc}) will clean up packages that were installed from within the
6269 environment and are no longer used outside of it.
6271 @vindex GUIX_ENVIRONMENT
6272 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
6273 variable in the shell it spawns; its value is the file name of the
6274 profile of this environment. This allows users to, say, define a
6275 specific prompt for development environments in their @file{.bashrc}
6276 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
6279 if [ -n "$GUIX_ENVIRONMENT" ]
6281 export PS1="\u@@\h \w [dev]\$ "
6286 ...@: or to browse the profile:
6289 $ ls "$GUIX_ENVIRONMENT/bin"
6292 Additionally, more than one package may be specified, in which case the
6293 union of the inputs for the given packages are used. For example, the
6294 command below spawns a shell where all of the dependencies of both Guile
6295 and Emacs are available:
6298 guix environment guile emacs
6301 Sometimes an interactive shell session is not desired. An arbitrary
6302 command may be invoked by placing the @code{--} token to separate the
6303 command from the rest of the arguments:
6306 guix environment guile -- make -j4
6309 In other situations, it is more convenient to specify the list of
6310 packages needed in the environment. For example, the following command
6311 runs @command{python} from an environment containing Python@tie{}3 and
6315 guix environment --ad-hoc python-numpy python -- python3
6318 Furthermore, one might want the dependencies of a package and also some
6319 additional packages that are not build-time or runtime dependencies, but
6320 are useful when developing nonetheless. Because of this, the
6321 @option{--ad-hoc} flag is positional. Packages appearing before
6322 @option{--ad-hoc} are interpreted as packages whose dependencies will be
6323 added to the environment. Packages appearing after are interpreted as
6324 packages that will be added to the environment directly. For example,
6325 the following command creates a Guix development environment that
6326 additionally includes Git and strace:
6329 guix environment --pure guix --ad-hoc git strace
6333 Sometimes it is desirable to isolate the environment as much as
6334 possible, for maximal purity and reproducibility. In particular, when
6335 using Guix on a host distro that is not Guix System, it is desirable to
6336 prevent access to @file{/usr/bin} and other system-wide resources from
6337 the development environment. For example, the following command spawns
6338 a Guile REPL in a ``container'' where only the store and the current
6339 working directory are mounted:
6342 guix environment --ad-hoc --container guile -- guile
6346 The @option{--container} option requires Linux-libre 3.19 or newer.
6349 @cindex certificates
6350 Another typical use case for containers is to run security-sensitive
6351 applications such as a web browser. To run Eolie, we must expose and
6352 share some files and directories; we include @code{nss-certs} and expose
6353 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
6354 @env{DISPLAY} environment variable since containerized graphical
6355 applications won't display without it.
6358 guix environment --preserve='^DISPLAY$' --container --network \
6359 --expose=/etc/machine-id \
6360 --expose=/etc/ssl/certs/ \
6361 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
6362 --ad-hoc eolie nss-certs dbus -- eolie
6365 The available options are summarized below.
6369 Set up the environment and check whether the shell would clobber
6370 environment variables. @xref{Invoking guix shell, @option{--check}},
6373 @item --root=@var{file}
6374 @itemx -r @var{file}
6375 @cindex persistent environment
6376 @cindex garbage collector root, for environments
6377 Make @var{file} a symlink to the profile for this environment, and
6378 register it as a garbage collector root.
6380 This is useful if you want to protect your environment from garbage
6381 collection, to make it ``persistent''.
6383 When this option is omitted, the environment is protected from garbage
6384 collection only for the duration of the @command{guix environment}
6385 session. This means that next time you recreate the same environment,
6386 you could have to rebuild or re-download packages. @xref{Invoking guix
6387 gc}, for more on GC roots.
6389 @item --expression=@var{expr}
6390 @itemx -e @var{expr}
6391 Create an environment for the package or list of packages that
6392 @var{expr} evaluates to.
6394 For example, running:
6397 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
6400 starts a shell with the environment for this specific variant of the
6406 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
6409 starts a shell with all the base system packages available.
6411 The above commands only use the default output of the given packages.
6412 To select other outputs, two element tuples can be specified:
6415 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
6418 @item --load=@var{file}
6419 @itemx -l @var{file}
6420 Create an environment for the package or list of packages that the code
6421 within @var{file} evaluates to.
6423 As an example, @var{file} might contain a definition like this
6424 (@pxref{Defining Packages}):
6427 @verbatiminclude environment-gdb.scm
6430 @item --manifest=@var{file}
6431 @itemx -m @var{file}
6432 Create an environment for the packages contained in the manifest object
6433 returned by the Scheme code in @var{file}. This option can be repeated
6434 several times, in which case the manifests are concatenated.
6436 This is similar to the same-named option in @command{guix package}
6437 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
6440 @xref{shell-export-manifest, @command{guix shell --export-manifest}},
6441 for information on how to ``convert'' command-line options into a
6445 Include all specified packages in the resulting environment, as if an
6446 @i{ad hoc} package were defined with them as inputs. This option is
6447 useful for quickly creating an environment without having to write a
6448 package expression to contain the desired inputs.
6450 For instance, the command:
6453 guix environment --ad-hoc guile guile-sdl -- guile
6456 runs @command{guile} in an environment where Guile and Guile-SDL are
6459 Note that this example implicitly asks for the default output of
6460 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
6461 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
6462 of @code{glib} (@pxref{Packages with Multiple Outputs}).
6464 This option may be composed with the default behavior of @command{guix
6465 environment}. Packages appearing before @option{--ad-hoc} are
6466 interpreted as packages whose dependencies will be added to the
6467 environment, the default behavior. Packages appearing after are
6468 interpreted as packages that will be added to the environment directly.
6470 @item --profile=@var{profile}
6471 @itemx -p @var{profile}
6472 Create an environment containing the packages installed in @var{profile}.
6473 Use @command{guix package} (@pxref{Invoking guix package}) to create
6474 and manage profiles.
6477 Unset existing environment variables when building the new environment, except
6478 those specified with @option{--preserve} (see below). This has the effect of
6479 creating an environment in which search paths only contain package inputs.
6481 @item --preserve=@var{regexp}
6482 @itemx -E @var{regexp}
6483 When used alongside @option{--pure}, preserve the environment variables
6484 matching @var{regexp}---in other words, put them on a ``white list'' of
6485 environment variables that must be preserved. This option can be repeated
6489 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
6493 This example runs @command{mpirun} in a context where the only environment
6494 variables defined are @env{PATH}, environment variables whose name starts
6495 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
6498 @item --search-paths
6499 Display the environment variable definitions that make up the
6502 @item --system=@var{system}
6503 @itemx -s @var{system}
6504 Attempt to build for @var{system}---e.g., @code{i686-linux}.
6509 Run @var{command} within an isolated container. The current working
6510 directory outside the container is mapped inside the container.
6511 Additionally, unless overridden with @option{--user}, a dummy home
6512 directory is created that matches the current user's home directory, and
6513 @file{/etc/passwd} is configured accordingly.
6515 The spawned process runs as the current user outside the container. Inside
6516 the container, it has the same UID and GID as the current user, unless
6517 @option{--user} is passed (see below).
6521 For containers, share the network namespace with the host system.
6522 Containers created without this flag only have access to the loopback
6525 @item --link-profile
6527 For containers, link the environment profile to @file{~/.guix-profile}
6528 within the container and set @code{GUIX_ENVIRONMENT} to that.
6529 This is equivalent to making @file{~/.guix-profile} a symlink to the
6530 actual profile within the container.
6531 Linking will fail and abort the environment if the directory already
6532 exists, which will certainly be the case if @command{guix environment}
6533 was invoked in the user's home directory.
6535 Certain packages are configured to look in @file{~/.guix-profile} for
6536 configuration files and data;@footnote{For example, the
6537 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
6538 for additional fonts.} @option{--link-profile} allows these programs to
6539 behave as expected within the environment.
6541 @item --user=@var{user}
6542 @itemx -u @var{user}
6543 For containers, use the username @var{user} in place of the current
6544 user. The generated @file{/etc/passwd} entry within the container will
6545 contain the name @var{user}, the home directory will be
6546 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
6547 the UID and GID inside the container are 1000. @var{user}
6548 need not exist on the system.
6550 Additionally, any shared or exposed path (see @option{--share} and
6551 @option{--expose} respectively) whose target is within the current user's
6552 home directory will be remapped relative to @file{/home/USER}; this
6553 includes the automatic mapping of the current working directory.
6556 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
6558 guix environment --container --user=foo \
6559 --expose=$HOME/test \
6560 --expose=/tmp/target=$HOME/target
6563 While this will limit the leaking of user identity through home paths
6564 and each of the user fields, this is only one useful component of a
6565 broader privacy/anonymity solution---not one in and of itself.
6568 For containers, the default behavior is to share the current working
6569 directory with the isolated container and immediately change to that
6570 directory within the container. If this is undesirable,
6571 @option{--no-cwd} will cause the current working directory to @emph{not}
6572 be automatically shared and will change to the user's home directory
6573 within the container instead. See also @option{--user}.
6575 @item --expose=@var{source}[=@var{target}]
6576 @itemx --share=@var{source}[=@var{target}]
6577 For containers, @option{--expose} (resp. @option{--share}) exposes the
6578 file system @var{source} from the host system as the read-only
6579 (resp. writable) file system @var{target} within the container. If
6580 @var{target} is not specified, @var{source} is used as the target mount
6581 point in the container.
6583 The example below spawns a Guile REPL in a container in which the user's
6584 home directory is accessible read-only via the @file{/exchange}
6588 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
6593 @command{guix environment}
6594 also supports all of the common build options that @command{guix
6595 build} supports (@pxref{Common Build Options}) as well as package
6596 transformation options (@pxref{Package Transformation Options}).
6598 @node Invoking guix pack
6599 @section Invoking @command{guix pack}
6601 Occasionally you want to pass software to people who are not (yet!)
6602 lucky enough to be using Guix. You'd tell them to run @command{guix
6603 package -i @var{something}}, but that's not possible in this case. This
6604 is where @command{guix pack} comes in.
6607 If you are looking for ways to exchange binaries among machines that
6608 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
6609 publish}, and @ref{Invoking guix archive}.
6614 @cindex application bundle
6615 @cindex software bundle
6616 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
6617 @dfn{software bundle}: it creates a tarball or some other archive
6618 containing the binaries of the software you're interested in, and all
6619 its dependencies. The resulting archive can be used on any machine that
6620 does not have Guix, and people can run the exact same binaries as those
6621 you have with Guix. The pack itself is created in a bit-reproducible
6622 fashion, so anyone can verify that it really contains the build results
6623 that you pretend to be shipping.
6625 For example, to create a bundle containing Guile, Emacs, Geiser, and all
6626 their dependencies, you can run:
6629 $ guix pack guile emacs emacs-geiser
6631 /gnu/store/@dots{}-pack.tar.gz
6634 The result here is a tarball containing a @file{/gnu/store} directory
6635 with all the relevant packages. The resulting tarball contains a
6636 @dfn{profile} with the three packages of interest; the profile is the
6637 same as would be created by @command{guix package -i}. It is this
6638 mechanism that is used to create Guix's own standalone binary tarball
6639 (@pxref{Binary Installation}).
6641 Users of this pack would have to run
6642 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
6643 find inconvenient. To work around it, you can create, say, a
6644 @file{/opt/gnu/bin} symlink to the profile:
6647 guix pack -S /opt/gnu/bin=bin guile emacs emacs-geiser
6651 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
6653 @cindex relocatable binaries, with @command{guix pack}
6654 What if the recipient of your pack does not have root privileges on
6655 their machine, and thus cannot unpack it in the root file system? In
6656 that case, you will want to use the @option{--relocatable} option (see
6657 below). This option produces @dfn{relocatable binaries}, meaning they
6658 they can be placed anywhere in the file system hierarchy: in the example
6659 above, users can unpack your tarball in their home directory and
6660 directly run @file{./opt/gnu/bin/guile}.
6662 @cindex Docker, build an image with guix pack
6663 Alternatively, you can produce a pack in the Docker image format using
6664 the following command:
6667 guix pack -f docker -S /bin=bin guile guile-readline
6671 The result is a tarball that can be passed to the @command{docker load}
6672 command, followed by @code{docker run}:
6675 docker load < @var{file}
6676 docker run -ti guile-guile-readline /bin/guile
6680 where @var{file} is the image returned by @var{guix pack}, and
6681 @code{guile-guile-readline} is its ``image tag''. See the
6682 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
6683 documentation} for more information.
6685 @cindex Singularity, build an image with guix pack
6686 @cindex SquashFS, build an image with guix pack
6687 Yet another option is to produce a SquashFS image with the following
6691 guix pack -f squashfs bash guile emacs emacs-geiser
6695 The result is a SquashFS file system image that can either be mounted or
6696 directly be used as a file system container image with the
6697 @uref{https://www.sylabs.io/docs/, Singularity container execution
6698 environment}, using commands like @command{singularity shell} or
6699 @command{singularity exec}.
6701 Several command-line options allow you to customize your pack:
6704 @item --format=@var{format}
6705 @itemx -f @var{format}
6706 Produce a pack in the given @var{format}.
6708 The available formats are:
6712 This is the default format. It produces a tarball containing all the
6713 specified binaries and symlinks.
6716 This produces a tarball that follows the
6717 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
6718 Docker Image Specification}. The ``repository name'' as it appears in
6719 the output of the @command{docker images} command is computed from
6720 package names passed on the command line or in the manifest file.
6723 This produces a SquashFS image containing all the specified binaries and
6724 symlinks, as well as empty mount points for virtual file systems like
6728 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
6729 For that reason, @command{guix pack -f squashfs} always implies @code{-S
6730 /bin=bin}. Thus, your @command{guix pack} invocation must always start
6731 with something like:
6734 guix pack -f squashfs bash @dots{}
6737 If you forget the @code{bash} (or similar) package, @command{singularity
6738 run} and @command{singularity exec} will fail with an unhelpful ``no
6739 such file or directory'' message.
6743 This produces a Debian archive (a package with the @samp{.deb} file
6744 extension) containing all the specified binaries and symbolic links,
6745 that can be installed on top of any dpkg-based GNU(/Linux) distribution.
6746 Advanced options can be revealed via the @option{--help-deb-format}
6747 option. They allow embedding control files for more fine-grained
6748 control, such as activating specific triggers or providing a maintainer
6749 configure script to run arbitrary setup code upon installation.
6752 guix pack -f deb -C xz -S /usr/bin/hello=bin/hello hello
6756 Because archives produced with @command{guix pack} contain a collection
6757 of store items and because each @command{dpkg} package must not have
6758 conflicting files, in practice that means you likely won't be able to
6759 install more than one such archive on a given system.
6763 @command{dpkg} will assume ownership of any files contained in the pack
6764 that it does @emph{not} know about. It is unwise to install
6765 Guix-produced @samp{.deb} files on a system where @file{/gnu/store} is
6766 shared by other software, such as a Guix installation or other, non-deb
6772 @cindex relocatable binaries
6775 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
6776 anywhere in the file system hierarchy and run from there.
6778 When this option is passed once, the resulting binaries require support for
6779 @dfn{user namespaces} in the kernel Linux; when passed
6780 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
6781 PRoot support, can be thought of as the abbreviation of ``Really
6782 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
6783 other techniques if user namespaces are unavailable, and essentially
6784 work anywhere---see below for the implications.
6786 For example, if you create a pack containing Bash with:
6789 guix pack -RR -S /mybin=bin bash
6793 ...@: you can copy that pack to a machine that lacks Guix, and from your
6794 home directory as a normal user, run:
6802 In that shell, if you type @code{ls /gnu/store}, you'll notice that
6803 @file{/gnu/store} shows up and contains all the dependencies of
6804 @code{bash}, even though the machine actually lacks @file{/gnu/store}
6805 altogether! That is probably the simplest way to deploy Guix-built
6806 software on a non-Guix machine.
6809 By default, relocatable binaries rely on the @dfn{user namespace} feature of
6810 the kernel Linux, which allows unprivileged users to mount or change root.
6811 Old versions of Linux did not support it, and some GNU/Linux distributions
6814 To produce relocatable binaries that work even in the absence of user
6815 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
6816 case, binaries will try user namespace support and fall back to another
6817 @dfn{execution engine} if user namespaces are not supported. The
6818 following execution engines are supported:
6822 Try user namespaces and fall back to PRoot if user namespaces are not
6823 supported (see below).
6826 Try user namespaces and fall back to Fakechroot if user namespaces are
6827 not supported (see below).
6830 Run the program through user namespaces and abort if they are not
6834 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
6835 provides the necessary
6836 support for file system virtualization. It achieves that by using the
6837 @code{ptrace} system call on the running program. This approach has the
6838 advantage to work without requiring special kernel support, but it incurs
6839 run-time overhead every time a system call is made.
6842 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
6843 Fakechroot} virtualizes file system accesses by intercepting calls to C
6844 library functions such as @code{open}, @code{stat}, @code{exec}, and so
6845 on. Unlike PRoot, it incurs very little overhead. However, it does not
6846 always work: for example, some file system accesses made from within the
6847 C library are not intercepted, and file system accesses made @i{via}
6848 direct syscalls are not intercepted either, leading to erratic behavior.
6851 @vindex GUIX_EXECUTION_ENGINE
6852 When running a wrapped program, you can explicitly request one of the
6853 execution engines listed above by setting the
6854 @env{GUIX_EXECUTION_ENGINE} environment variable accordingly.
6857 @cindex entry point, for Docker images
6858 @item --entry-point=@var{command}
6859 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
6860 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
6861 support it. @var{command} must be relative to the profile contained in the
6864 The entry point specifies the command that tools like @code{docker run} or
6865 @code{singularity run} automatically start by default. For example, you can
6869 guix pack -f docker --entry-point=bin/guile guile
6872 The resulting pack can easily be loaded and @code{docker run} with no extra
6873 arguments will spawn @code{bin/guile}:
6876 docker load -i pack.tar.gz
6877 docker run @var{image-id}
6880 @item --expression=@var{expr}
6881 @itemx -e @var{expr}
6882 Consider the package @var{expr} evaluates to.
6884 This has the same purpose as the same-named option in @command{guix
6885 build} (@pxref{Additional Build Options, @option{--expression} in
6886 @command{guix build}}).
6888 @anchor{pack-manifest}
6889 @item --manifest=@var{file}
6890 @itemx -m @var{file}
6891 Use the packages contained in the manifest object returned by the Scheme
6892 code in @var{file}. This option can be repeated several times, in which
6893 case the manifests are concatenated.
6895 This has a similar purpose as the same-named option in @command{guix
6896 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
6897 same manifest files. It allows you to define a collection of packages
6898 once and use it both for creating profiles and for creating archives
6899 for use on machines that do not have Guix installed. Note that you can
6900 specify @emph{either} a manifest file @emph{or} a list of packages,
6903 @xref{Writing Manifests}, for information on how to write a manifest.
6904 @xref{shell-export-manifest, @command{guix shell --export-manifest}},
6905 for information on how to ``convert'' command-line options into a
6908 @item --system=@var{system}
6909 @itemx -s @var{system}
6910 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
6911 the system type of the build host.
6913 @item --target=@var{triplet}
6914 @cindex cross-compilation
6915 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
6916 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
6917 configuration triplets,, autoconf, Autoconf}).
6919 @item --compression=@var{tool}
6920 @itemx -C @var{tool}
6921 Compress the resulting tarball using @var{tool}---one of @code{gzip},
6922 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
6925 @item --symlink=@var{spec}
6926 @itemx -S @var{spec}
6927 Add the symlinks specified by @var{spec} to the pack. This option can
6928 appear several times.
6930 @var{spec} has the form @code{@var{source}=@var{target}}, where
6931 @var{source} is the symlink that will be created and @var{target} is the
6934 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
6935 symlink pointing to the @file{bin} sub-directory of the profile.
6937 @item --save-provenance
6938 Save provenance information for the packages passed on the command line.
6939 Provenance information includes the URL and commit of the channels in use
6942 Provenance information is saved in the
6943 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
6944 usual package metadata---the name and version of each package, their
6945 propagated inputs, and so on. It is useful information to the recipient of
6946 the pack, who then knows how the pack was (supposedly) obtained.
6948 This option is not enabled by default because, like timestamps, provenance
6949 information contributes nothing to the build process. In other words, there
6950 is an infinity of channel URLs and commit IDs that can lead to the same pack.
6951 Recording such ``silent'' metadata in the output thus potentially breaks the
6952 source-to-binary bitwise reproducibility property.
6954 @item --root=@var{file}
6955 @itemx -r @var{file}
6956 @cindex garbage collector root, for packs
6957 Make @var{file} a symlink to the resulting pack, and register it as a garbage
6960 @item --localstatedir
6961 @itemx --profile-name=@var{name}
6962 Include the ``local state directory'', @file{/var/guix}, in the resulting
6963 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
6964 profile---by default @var{name} is @code{guix-profile}, which corresponds to
6965 @file{~root/.guix-profile}.
6967 @file{/var/guix} contains the store database (@pxref{The Store}) as well
6968 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
6969 the pack means that the store is ``complete'' and manageable by Guix;
6970 not providing it pack means that the store is ``dead'': items cannot be
6971 added to it or removed from it after extraction of the pack.
6973 One use case for this is the Guix self-contained binary tarball
6974 (@pxref{Binary Installation}).
6978 Print the name of the derivation that builds the pack.
6981 Use the bootstrap binaries to build the pack. This option is only
6982 useful to Guix developers.
6985 In addition, @command{guix pack} supports all the common build options
6986 (@pxref{Common Build Options}) and all the package transformation
6987 options (@pxref{Package Transformation Options}).
6990 @node The GCC toolchain
6991 @section The GCC toolchain
6995 @cindex linker wrapper
6996 @cindex toolchain, for C development
6997 @cindex toolchain, for Fortran development
6999 If you need a complete toolchain for compiling and linking C or C++
7000 source code, use the @code{gcc-toolchain} package. This package
7001 provides a complete GCC toolchain for C/C++ development, including GCC
7002 itself, the GNU C Library (headers and binaries, plus debugging symbols
7003 in the @code{debug} output), Binutils, and a linker wrapper.
7005 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
7006 passed to the linker, add corresponding @code{-rpath} arguments, and
7007 invoke the actual linker with this new set of arguments. You can instruct the
7008 wrapper to refuse to link against libraries not in the store by setting the
7009 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
7011 The package @code{gfortran-toolchain} provides a complete GCC toolchain
7012 for Fortran development. For other languages, please use
7013 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
7016 @node Invoking guix git authenticate
7017 @section Invoking @command{guix git authenticate}
7019 The @command{guix git authenticate} command authenticates a Git checkout
7020 following the same rule as for channels (@pxref{channel-authentication,
7021 channel authentication}). That is, starting from a given commit, it
7022 ensures that all subsequent commits are signed by an OpenPGP key whose
7023 fingerprint appears in the @file{.guix-authorizations} file of its
7026 You will find this command useful if you maintain a channel. But in
7027 fact, this authentication mechanism is useful in a broader context, so
7028 you might want to use it for Git repositories that have nothing to do
7031 The general syntax is:
7034 guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
7037 By default, this command authenticates the Git checkout in the current
7038 directory; it outputs nothing and exits with exit code zero on success
7039 and non-zero on failure. @var{commit} above denotes the first commit
7040 where authentication takes place, and @var{signer} is the OpenPGP
7041 fingerprint of public key used to sign @var{commit}. Together, they
7042 form a ``channel introduction'' (@pxref{channel-authentication, channel
7043 introduction}). The options below allow you to fine-tune the process.
7046 @item --repository=@var{directory}
7047 @itemx -r @var{directory}
7048 Open the Git repository in @var{directory} instead of the current
7051 @item --keyring=@var{reference}
7052 @itemx -k @var{reference}
7053 Load OpenPGP keyring from @var{reference}, the reference of a branch
7054 such as @code{origin/keyring} or @code{my-keyring}. The branch must
7055 contain OpenPGP public keys in @file{.key} files, either in binary form
7056 or ``ASCII-armored''. By default the keyring is loaded from the branch
7057 named @code{keyring}.
7060 Display commit signing statistics upon completion.
7062 @item --cache-key=@var{key}
7063 Previously-authenticated commits are cached in a file under
7064 @file{~/.cache/guix/authentication}. This option forces the cache to be
7065 stored in file @var{key} in that directory.
7067 @item --historical-authorizations=@var{file}
7068 By default, any commit whose parent commit(s) lack the
7069 @file{.guix-authorizations} file is considered inauthentic. In
7070 contrast, this option considers the authorizations in @var{file} for any
7071 commit that lacks @file{.guix-authorizations}. The format of @var{file}
7072 is the same as that of @file{.guix-authorizations}
7073 (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
7077 @c *********************************************************************
7078 @node Programming Interface
7079 @chapter Programming Interface
7081 GNU Guix provides several Scheme programming interfaces (APIs) to
7082 define, build, and query packages. The first interface allows users to
7083 write high-level package definitions. These definitions refer to
7084 familiar packaging concepts, such as the name and version of a package,
7085 its build system, and its dependencies. These definitions can then be
7086 turned into concrete build actions.
7088 Build actions are performed by the Guix daemon, on behalf of users. In a
7089 standard setup, the daemon has write access to the store---the
7090 @file{/gnu/store} directory---whereas users do not. The recommended
7091 setup also has the daemon perform builds in chroots, under specific
7092 build users, to minimize interference with the rest of the system.
7095 Lower-level APIs are available to interact with the daemon and the
7096 store. To instruct the daemon to perform a build action, users actually
7097 provide it with a @dfn{derivation}. A derivation is a low-level
7098 representation of the build actions to be taken, and the environment in
7099 which they should occur---derivations are to package definitions what
7100 assembly is to C programs. The term ``derivation'' comes from the fact
7101 that build results @emph{derive} from them.
7103 This chapter describes all these APIs in turn, starting from high-level
7104 package definitions.
7107 * Package Modules:: Packages from the programmer's viewpoint.
7108 * Defining Packages:: Defining new packages.
7109 * Defining Package Variants:: Customizing packages.
7110 * Writing Manifests:: The bill of materials of your environment.
7111 * Build Systems:: Specifying how packages are built.
7112 * Build Phases:: Phases of the build process of a package.
7113 * Build Utilities:: Helpers for your package definitions and more.
7114 * Search Paths:: Declaring search path environment variables.
7115 * The Store:: Manipulating the package store.
7116 * Derivations:: Low-level interface to package derivations.
7117 * The Store Monad:: Purely functional interface to the store.
7118 * G-Expressions:: Manipulating build expressions.
7119 * Invoking guix repl:: Programming Guix in Guile
7120 * Using Guix Interactively:: Fine-grain interaction at the REPL.
7123 @node Package Modules
7124 @section Package Modules
7126 From a programming viewpoint, the package definitions of the
7127 GNU distribution are provided by Guile modules in the @code{(gnu packages
7128 @dots{})} name space@footnote{Note that packages under the @code{(gnu
7129 packages @dots{})} module name space are not necessarily ``GNU
7130 packages''. This module naming scheme follows the usual Guile module
7131 naming convention: @code{gnu} means that these modules are distributed
7132 as part of the GNU system, and @code{packages} identifies modules that
7133 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
7134 Reference Manual}). For instance, the @code{(gnu packages emacs)}
7135 module exports a variable named @code{emacs}, which is bound to a
7136 @code{<package>} object (@pxref{Defining Packages}).
7138 The @code{(gnu packages @dots{})} module name space is
7139 automatically scanned for packages by the command-line tools. For
7140 instance, when running @code{guix install emacs}, all the @code{(gnu
7141 packages @dots{})} modules are scanned until one that exports a package
7142 object whose name is @code{emacs} is found. This package search
7143 facility is implemented in the @code{(gnu packages)} module.
7145 @cindex customization, of packages
7146 @cindex package module search path
7147 Users can store package definitions in modules with different
7148 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
7149 name and module name must match. For instance, the @code{(my-packages
7150 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
7151 relative to the load path specified with @option{--load-path} or
7152 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
7153 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
7154 these package definitions visible to the user interfaces:
7158 By adding the directory containing your package modules to the search path
7159 with the @code{-L} flag of @command{guix package} and other commands
7160 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
7161 environment variable described below.
7164 By defining a @dfn{channel} and configuring @command{guix pull} so that it
7165 pulls from it. A channel is essentially a Git repository containing package
7166 modules. @xref{Channels}, for more information on how to define and use
7170 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
7172 @defvr {Environment Variable} GUIX_PACKAGE_PATH
7173 This is a colon-separated list of directories to search for additional
7174 package modules. Directories listed in this variable take precedence
7175 over the own modules of the distribution.
7178 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
7179 each package is built based solely on other packages in the
7180 distribution. The root of this dependency graph is a small set of
7181 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
7182 bootstrap)} module. For more information on bootstrapping,
7183 @pxref{Bootstrapping}.
7185 @node Defining Packages
7186 @section Defining Packages
7188 The high-level interface to package definitions is implemented in the
7189 @code{(guix packages)} and @code{(guix build-system)} modules. As an
7190 example, the package definition, or @dfn{recipe}, for the GNU Hello
7191 package looks like this:
7194 (define-module (gnu packages hello)
7195 #:use-module (guix packages)
7196 #:use-module (guix download)
7197 #:use-module (guix build-system gnu)
7198 #:use-module (guix licenses)
7199 #:use-module (gnu packages gawk))
7201 (define-public hello
7207 (uri (string-append "mirror://gnu/hello/hello-" version
7211 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
7212 (build-system gnu-build-system)
7213 (arguments '(#:configure-flags '("--enable-silent-rules")))
7214 (inputs (list gawk))
7215 (synopsis "Hello, GNU world: An example GNU package")
7216 (description "Guess what GNU Hello prints!")
7217 (home-page "https://www.gnu.org/software/hello/")
7222 Without being a Scheme expert, the reader may have guessed the meaning
7223 of the various fields here. This expression binds the variable
7224 @code{hello} to a @code{<package>} object, which is essentially a record
7225 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
7226 This package object can be inspected using procedures found in the
7227 @code{(guix packages)} module; for instance, @code{(package-name hello)}
7228 returns---surprise!---@code{"hello"}.
7230 With luck, you may be able to import part or all of the definition of
7231 the package you are interested in from another repository, using the
7232 @code{guix import} command (@pxref{Invoking guix import}).
7234 In the example above, @code{hello} is defined in a module of its own,
7235 @code{(gnu packages hello)}. Technically, this is not strictly
7236 necessary, but it is convenient to do so: all the packages defined in
7237 modules under @code{(gnu packages @dots{})} are automatically known to
7238 the command-line tools (@pxref{Package Modules}).
7240 There are a few points worth noting in the above package definition:
7244 The @code{source} field of the package is an @code{<origin>} object
7245 (@pxref{origin Reference}, for the complete reference).
7246 Here, the @code{url-fetch} method from @code{(guix download)} is used,
7247 meaning that the source is a file to be downloaded over FTP or HTTP.
7249 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
7250 the GNU mirrors defined in @code{(guix download)}.
7252 The @code{sha256} field specifies the expected SHA256 hash of the file
7253 being downloaded. It is mandatory, and allows Guix to check the
7254 integrity of the file. The @code{(base32 @dots{})} form introduces the
7255 base32 representation of the hash. You can obtain this information with
7256 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
7257 hash} (@pxref{Invoking guix hash}).
7260 When needed, the @code{origin} form can also have a @code{patches} field
7261 listing patches to be applied, and a @code{snippet} field giving a
7262 Scheme expression to modify the source code.
7265 @cindex GNU Build System
7266 The @code{build-system} field specifies the procedure to build the
7267 package (@pxref{Build Systems}). Here, @code{gnu-build-system}
7268 represents the familiar GNU Build System, where packages may be
7269 configured, built, and installed with the usual @code{./configure &&
7270 make && make check && make install} command sequence.
7272 When you start packaging non-trivial software, you may need tools to
7273 manipulate those build phases, manipulate files, and so on. @xref{Build
7274 Utilities}, for more on this.
7277 The @code{arguments} field specifies options for the build system
7278 (@pxref{Build Systems}). Here it is interpreted by
7279 @code{gnu-build-system} as a request run @file{configure} with the
7280 @option{--enable-silent-rules} flag.
7286 @cindex backquote (quasiquote)
7289 @cindex comma (unquote)
7292 What about these quote (@code{'}) characters? They are Scheme syntax to
7293 introduce a literal list; @code{'} is synonymous with @code{quote}.
7294 Sometimes you'll also see @code{`} (a backquote, synonymous with
7295 @code{quasiquote}) and @code{,} (a comma, synonymous with @code{unquote}).
7296 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
7297 for details. Here the value of the @code{arguments} field is a list of
7298 arguments passed to the build system down the road, as with @code{apply}
7299 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
7302 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
7303 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
7304 @code{#:configure-flags} is a keyword used to pass a keyword argument
7305 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
7309 The @code{inputs} field specifies inputs to the build process---i.e.,
7310 build-time or run-time dependencies of the package. Here, we add
7311 an input, a reference to the @code{gawk}
7312 variable; @code{gawk} is itself bound to a @code{<package>} object.
7314 Note that GCC, Coreutils, Bash, and other essential tools do not need to
7315 be specified as inputs here. Instead, @code{gnu-build-system} takes care
7316 of ensuring that they are present (@pxref{Build Systems}).
7318 However, any other dependencies need to be specified in the
7319 @code{inputs} field. Any dependency not specified here will simply be
7320 unavailable to the build process, possibly leading to a build failure.
7323 @xref{package Reference}, for a full description of possible fields.
7325 Once a package definition is in place, the
7326 package may actually be built using the @code{guix build} command-line
7327 tool (@pxref{Invoking guix build}), troubleshooting any build failures
7328 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
7329 package definition using the @command{guix edit} command
7330 (@pxref{Invoking guix edit}).
7331 @xref{Packaging Guidelines}, for
7332 more information on how to test package definitions, and
7333 @ref{Invoking guix lint}, for information on how to check a definition
7334 for style conformance.
7335 @vindex GUIX_PACKAGE_PATH
7336 Lastly, @pxref{Channels}, for information
7337 on how to extend the distribution by adding your own package definitions
7340 Finally, updating the package definition to a new upstream version
7341 can be partly automated by the @command{guix refresh} command
7342 (@pxref{Invoking guix refresh}).
7344 Behind the scenes, a derivation corresponding to the @code{<package>}
7345 object is first computed by the @code{package-derivation} procedure.
7346 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
7347 The build actions it prescribes may then be realized by using the
7348 @code{build-derivations} procedure (@pxref{The Store}).
7350 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
7351 Return the @code{<derivation>} object of @var{package} for @var{system}
7352 (@pxref{Derivations}).
7354 @var{package} must be a valid @code{<package>} object, and @var{system}
7355 must be a string denoting the target system type---e.g.,
7356 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
7357 must be a connection to the daemon, which operates on the store
7358 (@pxref{The Store}).
7362 @cindex cross-compilation
7363 Similarly, it is possible to compute a derivation that cross-builds a
7364 package for some other system:
7366 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
7367 @var{package} @var{target} [@var{system}]
7368 Return the @code{<derivation>} object of @var{package} cross-built from
7369 @var{system} to @var{target}.
7371 @var{target} must be a valid GNU triplet denoting the target hardware
7372 and operating system, such as @code{"aarch64-linux-gnu"}
7373 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
7376 Once you have package definitions, you can easily define @emph{variants}
7377 of those packages. @xref{Defining Package Variants}, for more on that.
7380 * package Reference:: The package data type.
7381 * origin Reference:: The origin data type.
7385 @node package Reference
7386 @subsection @code{package} Reference
7388 This section summarizes all the options available in @code{package}
7389 declarations (@pxref{Defining Packages}).
7391 @deftp {Data Type} package
7392 This is the data type representing a package recipe.
7396 The name of the package, as a string.
7398 @item @code{version}
7399 The version of the package, as a string. @xref{Version Numbers}, for
7403 An object telling how the source code for the package should be
7404 acquired. Most of the time, this is an @code{origin} object, which
7405 denotes a file fetched from the Internet (@pxref{origin Reference}). It
7406 can also be any other ``file-like'' object such as a @code{local-file},
7407 which denotes a file from the local file system (@pxref{G-Expressions,
7408 @code{local-file}}).
7410 @item @code{build-system}
7411 The build system that should be used to build the package (@pxref{Build
7414 @item @code{arguments} (default: @code{'()})
7415 The arguments that should be passed to the build system (@pxref{Build
7416 Systems}). This is a list, typically containing sequential
7417 keyword-value pairs, as in this example:
7422 ;; several fields omitted
7424 (list #:tests? #f ;skip tests
7425 #:make-flags #~'("VERBOSE=1") ;pass flags to 'make'
7426 #:configure-flags #~'("--enable-frobbing"))))
7429 The exact set of supported keywords depends on the build system
7430 (@pxref{Build Systems}), but you will find that almost all of them honor
7431 @code{#:configure-flags}, @code{#:make-flags}, @code{#:tests?}, and
7432 @code{#:phases}. The @code{#:phases} keyword in particular lets you
7433 modify the set of build phases for your package (@pxref{Build Phases}).
7435 @item @code{inputs} (default: @code{'()})
7436 @itemx @code{native-inputs} (default: @code{'()})
7437 @itemx @code{propagated-inputs} (default: @code{'()})
7438 @cindex inputs, of packages
7439 These fields list dependencies of the package. Each element of these
7440 lists is either a package, origin, or other ``file-like object''
7441 (@pxref{G-Expressions}); to specify the output of that file-like object
7442 that should be used, pass a two-element list where the second element is
7443 the output (@pxref{Packages with Multiple Outputs}, for more on package
7444 outputs). For example, the list below specifies three inputs:
7447 (list libffi libunistring
7448 `(,glib "bin")) ;the "bin" output of GLib
7451 In the example above, the @code{"out"} output of @code{libffi} and
7452 @code{libunistring} is used.
7454 @quotation Compatibility Note
7455 Until version 1.3.0, input lists were a list of tuples,
7456 where each tuple has a label for the input (a string) as its
7457 first element, a package, origin, or derivation as its second element,
7458 and optionally the name of the output thereof that should be used, which
7459 defaults to @code{"out"}. For example, the list below is equivalent to
7460 the one above, but using the @dfn{old input style}:
7463 ;; Old input style (deprecated).
7464 `(("libffi" ,libffi)
7465 ("libunistring" ,libunistring)
7466 ("glib:bin" ,glib "bin")) ;the "bin" output of GLib
7469 This style is now deprecated; it is still supported but support will be
7470 removed in a future version. It should not be used for new package
7471 definitions. @xref{Invoking guix style}, on how to migrate to the new
7475 @cindex cross compilation, package dependencies
7476 The distinction between @code{native-inputs} and @code{inputs} is
7477 necessary when considering cross-compilation. When cross-compiling,
7478 dependencies listed in @code{inputs} are built for the @emph{target}
7479 architecture; conversely, dependencies listed in @code{native-inputs}
7480 are built for the architecture of the @emph{build} machine.
7482 @code{native-inputs} is typically used to list tools needed at
7483 build time, but not at run time, such as Autoconf, Automake, pkg-config,
7484 Gettext, or Bison. @command{guix lint} can report likely mistakes in
7485 this area (@pxref{Invoking guix lint}).
7487 @anchor{package-propagated-inputs}
7488 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
7489 specified packages will be automatically installed to profiles
7490 (@pxref{Features, the role of profiles in Guix}) alongside the package
7491 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
7492 package}}, for information on how @command{guix package} deals with
7495 For example this is necessary when packaging a C/C++ library that needs
7496 headers of another library to compile, or when a pkg-config file refers
7497 to another one @i{via} its @code{Requires} field.
7499 Another example where @code{propagated-inputs} is useful is for languages
7500 that lack a facility to record the run-time search path akin to the
7501 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
7502 more. When packaging libraries written in those languages, ensure they
7503 can find library code they depend on at run time by listing run-time
7504 dependencies in @code{propagated-inputs} rather than @code{inputs}.
7506 @item @code{outputs} (default: @code{'("out")})
7507 The list of output names of the package. @xref{Packages with Multiple
7508 Outputs}, for typical uses of additional outputs.
7510 @item @code{native-search-paths} (default: @code{'()})
7511 @itemx @code{search-paths} (default: @code{'()})
7512 A list of @code{search-path-specification} objects describing
7513 search-path environment variables honored by the package. @xref{Search
7514 Paths}, for more on search path specifications.
7516 As for inputs, the distinction between @code{native-search-paths} and
7517 @code{search-paths} only matters when cross-compiling. In a
7518 cross-compilation context, @code{native-search-paths} applies
7519 exclusively to native inputs whereas @code{search-paths} applies only to
7522 Packages such as cross-compilers care about target inputs---for
7523 instance, our (modified) GCC cross-compiler has
7524 @env{CROSS_C_INCLUDE_PATH} in @code{search-paths}, which allows it to
7525 pick @file{.h} files for the target system and @emph{not} those of
7526 native inputs. For the majority of packages though, only
7527 @code{native-search-paths} makes sense.
7529 @item @code{replacement} (default: @code{#f})
7530 This must be either @code{#f} or a package object that will be used as a
7531 @dfn{replacement} for this package. @xref{Security Updates, grafts},
7534 @item @code{synopsis}
7535 A one-line description of the package.
7537 @item @code{description}
7538 A more elaborate description of the package, as a string in Texinfo
7541 @item @code{license}
7542 @cindex license, of packages
7543 The license of the package; a value from @code{(guix licenses)},
7544 or a list of such values.
7546 @item @code{home-page}
7547 The URL to the home-page of the package, as a string.
7549 @item @code{supported-systems} (default: @code{%supported-systems})
7550 The list of systems supported by the package, as strings of the form
7551 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
7553 @item @code{location} (default: source location of the @code{package} form)
7554 The source location of the package. It is useful to override this when
7555 inheriting from another package, in which case this field is not
7556 automatically corrected.
7560 @deffn {Scheme Syntax} this-package
7561 When used in the @emph{lexical scope} of a package field definition, this
7562 identifier resolves to the package being defined.
7564 The example below shows how to add a package as a native input of itself when
7572 ;; When cross-compiled, Guile, for example, depends on
7573 ;; a native version of itself. Add it here.
7574 (native-inputs (if (%current-target-system)
7579 It is an error to refer to @code{this-package} outside a package definition.
7582 The following helper procedures are provided to help deal with package
7585 @deffn {Scheme Procedure} lookup-package-input @var{package} @var{name}
7586 @deffnx {Scheme Procedure} lookup-package-native-input @var{package} @var{name}
7587 @deffnx {Scheme Procedure} lookup-package-propagated-input @var{package} @var{name}
7588 @deffnx {Scheme Procedure} lookup-package-direct-input @var{package} @var{name}
7589 Look up @var{name} among @var{package}'s inputs (or native, propagated,
7590 or direct inputs). Return it if found, @code{#f} otherwise.
7592 @var{name} is the name of a package depended on. Here's how you might
7596 (use-modules (guix packages) (gnu packages base))
7598 (lookup-package-direct-input coreutils "gmp")
7599 @result{} #<package gmp@@6.2.1 @dots{}>
7602 In this example we obtain the @code{gmp} package that is among the
7603 direct inputs of @code{coreutils}.
7606 @cindex development inputs, of a package
7607 @cindex implicit inputs, of a package
7608 Sometimes you will want to obtain the list of inputs needed to
7609 @emph{develop} a package---all the inputs that are visible when the
7610 package is compiled. This is what the @code{package-development-inputs}
7613 @deffn {Scheme Procedure} package-development-inputs @var{package} @
7614 [@var{system}] [#:target #f]
7615 Return the list of inputs required by @var{package} for development
7616 purposes on @var{system}. When @var{target} is true, return the inputs
7617 needed to cross-compile @var{package} from @var{system} to
7618 @var{target}, where @var{target} is a triplet such as
7619 @code{"aarch64-linux-gnu"}.
7621 Note that the result includes both explicit inputs and implicit
7622 inputs---inputs automatically added by the build system (@pxref{Build
7623 Systems}). Let us take the @code{hello} package to illustrate that:
7626 (use-modules (gnu packages base) (guix packages))
7629 @result{} #<package hello@@2.10 gnu/packages/base.scm:79 7f585d4f6790>
7631 (package-direct-inputs hello)
7634 (package-development-inputs hello)
7635 @result{} (("source" @dots{}) ("tar" #<package tar@@1.32 @dots{}>) @dots{})
7638 In this example, @code{package-direct-inputs} returns the empty list,
7639 because @code{hello} has zero explicit dependencies. Conversely,
7640 @code{package-development-inputs} includes inputs implicitly added by
7641 @code{gnu-build-system} that are required to build @code{hello}: tar,
7642 gzip, GCC, libc, Bash, and more. To visualize it, @command{guix graph
7643 hello} would show you explicit inputs, whereas @command{guix graph -t
7644 bag hello} would include implicit inputs (@pxref{Invoking guix graph}).
7647 Because packages are regular Scheme objects that capture a complete
7648 dependency graph and associated build procedures, it is often useful to
7649 write procedures that take a package and return a modified version
7650 thereof according to some parameters. Below are a few examples.
7652 @cindex tool chain, choosing a package's tool chain
7653 @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
7654 Return a variant of @var{package} that uses @var{toolchain} instead of
7655 the default GNU C/C++ toolchain. @var{toolchain} must be a list of
7656 inputs (label/package tuples) providing equivalent functionality, such
7657 as the @code{gcc-toolchain} package.
7659 The example below returns a variant of the @code{hello} package built
7660 with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
7661 GNU C Library) instead of the default tool chain:
7664 (let ((toolchain (specification->package "gcc-toolchain@@10")))
7665 (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
7668 The build tool chain is part of the @dfn{implicit inputs} of
7669 packages---it's usually not listed as part of the various ``inputs''
7670 fields and is instead pulled in by the build system. Consequently, this
7671 procedure works by changing the build system of @var{package} so that it
7672 pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
7673 for more on build systems.
7676 @node origin Reference
7677 @subsection @code{origin} Reference
7679 This section documents @dfn{origins}. An @code{origin} declaration
7680 specifies data that must be ``produced''---downloaded, usually---and
7681 whose content hash is known in advance. Origins are primarily used to
7682 represent the source code of packages (@pxref{Defining Packages}). For
7683 that reason, the @code{origin} form allows you to declare patches to
7684 apply to the original source code as well as code snippets to modify it.
7686 @deftp {Data Type} origin
7687 This is the data type representing a source code origin.
7691 An object containing the URI of the source. The object type depends on
7692 the @code{method} (see below). For example, when using the
7693 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
7694 values are: a URL represented as a string, or a list thereof.
7696 @cindex fixed-output derivations, for download
7698 A monadic procedure that handles the given URI@. The procedure must
7699 accept at least three arguments: the value of the @code{uri} field and
7700 the hash algorithm and hash value specified by the @code{hash} field.
7701 It must return a store item or a derivation in the store monad
7702 (@pxref{The Store Monad}); most methods return a fixed-output derivation
7703 (@pxref{Derivations}).
7705 Commonly used methods include @code{url-fetch}, which fetches data from
7706 a URL, and @code{git-fetch}, which fetches data from a Git repository
7710 A bytevector containing the SHA-256 hash of the source. This is
7711 equivalent to providing a @code{content-hash} SHA256 object in the
7712 @code{hash} field described below.
7715 The @code{content-hash} object of the source---see below for how to use
7716 @code{content-hash}.
7718 You can obtain this information using @code{guix download}
7719 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
7722 @item @code{file-name} (default: @code{#f})
7723 The file name under which the source code should be saved. When this is
7724 @code{#f}, a sensible default value will be used in most cases. In case
7725 the source is fetched from a URL, the file name from the URL will be
7726 used. For version control checkouts, it is recommended to provide the
7727 file name explicitly because the default is not very descriptive.
7729 @item @code{patches} (default: @code{'()})
7730 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
7731 file-like objects}) pointing to patches to be applied to the source.
7733 This list of patches must be unconditional. In particular, it cannot
7734 depend on the value of @code{%current-system} or
7735 @code{%current-target-system}.
7737 @item @code{snippet} (default: @code{#f})
7738 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
7739 in the source directory. This is a convenient way to modify the source,
7740 sometimes more convenient than a patch.
7742 @item @code{patch-flags} (default: @code{'("-p1")})
7743 A list of command-line flags that should be passed to the @code{patch}
7746 @item @code{patch-inputs} (default: @code{#f})
7747 Input packages or derivations to the patching process. When this is
7748 @code{#f}, the usual set of inputs necessary for patching are provided,
7749 such as GNU@tie{}Patch.
7751 @item @code{modules} (default: @code{'()})
7752 A list of Guile modules that should be loaded during the patching
7753 process and while running the code in the @code{snippet} field.
7755 @item @code{patch-guile} (default: @code{#f})
7756 The Guile package that should be used in the patching process. When
7757 this is @code{#f}, a sensible default is used.
7761 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
7762 Construct a content hash object for the given @var{algorithm}, and with
7763 @var{value} as its hash value. When @var{algorithm} is omitted, assume
7764 it is @code{sha256}.
7766 @var{value} can be a literal string, in which case it is base32-decoded,
7767 or it can be a bytevector.
7769 The following forms are all equivalent:
7772 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
7773 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
7775 (content-hash (base32
7776 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
7777 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
7781 Technically, @code{content-hash} is currently implemented as a macro.
7782 It performs sanity checks at macro-expansion time, when possible, such
7783 as ensuring that @var{value} has the right size for @var{algorithm}.
7786 As we have seen above, how exactly the data an origin refers to is
7787 retrieved is determined by its @code{method} field. The @code{(guix
7788 download)} module provides the most common method, @code{url-fetch},
7791 @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
7792 [name] [#:executable? #f]
7793 Return a fixed-output derivation that fetches data from @var{url} (a
7794 string, or a list of strings denoting alternate URLs), which is expected
7795 to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
7796 the file name is the base name of URL; optionally, @var{name} can
7797 specify a different file name. When @var{executable?} is true, make the
7798 downloaded file executable.
7800 When one of the URL starts with @code{mirror://}, then its host part is
7801 interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
7803 Alternatively, when URL starts with @code{file://}, return the
7804 corresponding file name in the store.
7807 Likewise, the @code{(guix git-download)} module defines the
7808 @code{git-fetch} origin method, which fetches data from a Git version
7809 control repository, and the @code{git-reference} data type to describe
7810 the repository and revision to fetch.
7812 @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
7813 Return a fixed-output derivation that fetches @var{ref}, a
7814 @code{<git-reference>} object. The output is expected to have recursive
7815 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7816 the file name, or a generic name if @code{#f}.
7819 @deftp {Data Type} git-reference
7820 This data type represents a Git reference for @code{git-fetch} to
7825 The URL of the Git repository to clone.
7828 This string denotes either the commit to fetch (a hexadecimal string),
7829 or the tag to fetch. You can also use a ``short'' commit ID or a
7830 @command{git describe} style identifier such as
7831 @code{v1.0.1-10-g58d7909c97}.
7833 @item @code{recursive?} (default: @code{#f})
7834 This Boolean indicates whether to recursively fetch Git sub-modules.
7837 The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
7842 (url "https://git.savannah.gnu.org/git/hello.git")
7846 This is equivalent to the reference below, which explicitly names the
7851 (url "https://git.savannah.gnu.org/git/hello.git")
7852 (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
7856 For Mercurial repositories, the module @code{(guix hg-download)} defines
7857 the @code{hg-fetch} origin method and @code{hg-reference} data type for
7858 support of the Mercurial version control system.
7860 @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
7862 Return a fixed-output derivation that fetches @var{ref}, a
7863 @code{<hg-reference>} object. The output is expected to have recursive
7864 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7865 the file name, or a generic name if @code{#false}.
7868 @node Defining Package Variants
7869 @section Defining Package Variants
7871 @cindex customizing packages
7872 @cindex variants, of packages
7873 One of the nice things with Guix is that, given a package definition,
7874 you can easily @emph{derive} variants of that package---for a different
7875 upstream version, with different dependencies, different compilation
7876 options, and so on. Some of these custom packages can be defined
7877 straight from the command line (@pxref{Package Transformation Options}).
7878 This section describes how to define package variants in code. This can
7879 be useful in ``manifests'' (@pxref{Writing Manifests})
7880 and in your own package collection
7881 (@pxref{Creating a Channel}), among others!
7883 @cindex inherit, for package definitions
7884 As discussed earlier, packages are first-class objects in the Scheme
7885 language. The @code{(guix packages)} module provides the @code{package}
7886 construct to define new package objects (@pxref{package Reference}).
7887 The easiest way to define a package variant is using the @code{inherit}
7888 keyword together with @code{package}. This allows you to inherit from a
7889 package definition while overriding the fields you want.
7891 For example, given the @code{hello} variable, which contains a
7892 definition for the current version of GNU@tie{}Hello, here's how you
7893 would define a variant for version 2.2 (released in 2006, it's
7897 (use-modules (gnu packages base)) ;for 'hello'
7905 (uri (string-append "mirror://gnu/hello/hello-" version
7909 "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
7912 The example above corresponds to what the @option{--with-source} package
7913 transformation option does. Essentially @code{hello-2.2} preserves all
7914 the fields of @code{hello}, except @code{version} and @code{source},
7915 which it overrides. Note that the original @code{hello} variable is
7916 still there, in the @code{(gnu packages base)} module, unchanged. When
7917 you define a custom package like this, you are really @emph{adding} a
7918 new package definition; the original one remains available.
7920 You can just as well define variants with a different set of
7921 dependencies than the original package. For example, the default
7922 @code{gdb} package depends on @code{guile}, but since that is an
7923 optional dependency, you can define a variant that removes that
7927 (use-modules (gnu packages gdb)) ;for 'gdb'
7929 (define gdb-sans-guile
7932 (inputs (modify-inputs (package-inputs gdb)
7933 (delete "guile")))))
7936 The @code{modify-inputs} form above removes the @code{"guile"} package
7937 from the @code{inputs} field of @code{gdb}. The @code{modify-inputs}
7938 macro is a helper that can prove useful anytime you want to remove, add,
7939 or replace package inputs.
7941 @deffn {Scheme Syntax} modify-inputs @var{inputs} @var{clauses}
7942 Modify the given package inputs, as returned by @code{package-inputs} & co.,
7943 according to the given clauses. Each clause must have one of the
7947 @item (delete @var{name}@dots{})
7948 Delete from the inputs packages with the given @var{name}s (strings).
7950 @item (append @var{package}@dots{})
7951 Add @var{package}s to the end of the input list.
7953 @item (prepend @var{package}@dots{})
7954 Add @var{package}s to the front of the input list.
7957 The example below removes the GMP and ACL inputs of Coreutils and adds
7958 libcap to the back of the input list:
7961 (modify-inputs (package-inputs coreutils)
7962 (delete "gmp" "acl")
7966 The example below replaces the @code{guile} package from the inputs of
7967 @code{guile-redis} with @code{guile-2.2}:
7970 (modify-inputs (package-inputs guile-redis)
7971 (replace "guile" guile-2.2))
7974 The last type of clause is @code{prepend}, to add inputs to the front of
7978 In some cases, you may find it useful to write functions
7979 (``procedures'', in Scheme parlance) that return a package based on some
7980 parameters. For example, consider the @code{luasocket} library for the
7981 Lua programming language. We want to create @code{luasocket} packages
7982 for major versions of Lua. One way to do that is to define a procedure
7983 that takes a Lua package and returns a @code{luasocket} package that
7987 (define (make-lua-socket name lua)
7988 ;; Return a luasocket package built with LUA.
7992 ;; several fields omitted
7994 (synopsis "Socket library for Lua")))
7996 (define-public lua5.1-socket
7997 (make-lua-socket "lua5.1-socket" lua-5.1))
7999 (define-public lua5.2-socket
8000 (make-lua-socket "lua5.2-socket" lua-5.2))
8003 Here we have defined packages @code{lua5.1-socket} and
8004 @code{lua5.2-socket} by calling @code{make-lua-socket} with different
8005 arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
8006 more info on procedures. Having top-level public definitions for these
8007 two packages means that they can be referred to from the command line
8008 (@pxref{Package Modules}).
8010 @cindex package transformations
8011 These are pretty simple package variants. As a convenience, the
8012 @code{(guix transformations)} module provides a high-level interface
8013 that directly maps to the more sophisticated package transformation
8014 options (@pxref{Package Transformation Options}):
8016 @deffn {Scheme Procedure} options->transformation @var{opts}
8017 Return a procedure that, when passed an object to build (package,
8018 derivation, etc.), applies the transformations specified by @var{opts} and returns
8019 the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
8022 ((with-branch . "guile-gcrypt=master")
8023 (without-tests . "libgcrypt"))
8026 Each symbol names a transformation and the corresponding string is an argument
8027 to that transformation.
8030 For instance, a manifest equivalent to this command:
8034 --with-branch=guile-gcrypt=master \
8035 --with-debug-info=zlib
8039 ... would look like this:
8042 (use-modules (guix transformations))
8045 ;; The package transformation procedure.
8046 (options->transformation
8047 '((with-branch . "guile-gcrypt=master")
8048 (with-debug-info . "zlib"))))
8051 (list (transform (specification->package "guix"))))
8054 @cindex input rewriting
8055 @cindex dependency graph rewriting
8056 The @code{options->transformation} procedure is convenient, but it's
8057 perhaps also not as flexible as you may like. How is it implemented?
8058 The astute reader probably noticed that most package transformation
8059 options go beyond the superficial changes shown in the first examples of
8060 this section: they involve @dfn{input rewriting}, whereby the dependency
8061 graph of a package is rewritten by replacing specific inputs by others.
8063 Dependency graph rewriting, for the purposes of swapping packages in the
8064 graph, is what the @code{package-input-rewriting} procedure in
8065 @code{(guix packages)} implements.
8067 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
8068 [@var{rewrite-name}] [#:deep? #t]
8069 Return a procedure that, when passed a package, replaces its direct and
8070 indirect dependencies, including implicit inputs when @var{deep?} is
8071 true, according to @var{replacements}. @var{replacements} is a list of
8072 package pairs; the first element of each pair is the package to replace,
8073 and the second one is the replacement.
8075 Optionally, @var{rewrite-name} is a one-argument procedure that takes
8076 the name of a package and returns its new name after rewrite.
8080 Consider this example:
8083 (define libressl-instead-of-openssl
8084 ;; This is a procedure to replace OPENSSL by LIBRESSL,
8086 (package-input-rewriting `((,openssl . ,libressl))))
8088 (define git-with-libressl
8089 (libressl-instead-of-openssl git))
8093 Here we first define a rewriting procedure that replaces @var{openssl}
8094 with @var{libressl}. Then we use it to define a @dfn{variant} of the
8095 @var{git} package that uses @var{libressl} instead of @var{openssl}.
8096 This is exactly what the @option{--with-input} command-line option does
8097 (@pxref{Package Transformation Options, @option{--with-input}}).
8099 The following variant of @code{package-input-rewriting} can match packages to
8100 be replaced by name rather than by identity.
8102 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
8103 Return a procedure that, given a package, applies the given
8104 @var{replacements} to all the package graph, including implicit inputs
8105 unless @var{deep?} is false. @var{replacements} is a list of
8106 spec/procedures pair; each spec is a package specification such as
8107 @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
8108 package and returns a replacement for that package.
8111 The example above could be rewritten this way:
8114 (define libressl-instead-of-openssl
8115 ;; Replace all the packages called "openssl" with LibreSSL.
8116 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
8119 The key difference here is that, this time, packages are matched by spec and
8120 not by identity. In other words, any package in the graph that is called
8121 @code{openssl} will be replaced.
8123 A more generic procedure to rewrite a package dependency graph is
8124 @code{package-mapping}: it supports arbitrary changes to nodes in the
8127 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
8128 Return a procedure that, given a package, applies @var{proc} to all the packages
8129 depended on and returns the resulting package. The procedure stops recursion
8130 when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
8131 applied to implicit inputs as well.
8134 @node Writing Manifests
8135 @section Writing Manifests
8138 @cindex bill of materials (manifests)
8139 @command{guix} commands let you specify package lists on the command
8140 line. This is convenient, but as the command line becomes longer and
8141 less trivial, it quickly becomes more convenient to have that package
8142 list in what we call a @dfn{manifest}. A manifest is some sort of a
8143 ``bill of materials'' that defines a package set. You would typically
8144 come up with a code snippet that builds the manifest, store it in a
8145 file, say @file{manifest.scm}, and then pass that file to the
8146 @option{-m} (or @option{--manifest}) option that many @command{guix}
8147 commands support. For example, here's what a manifest for a simple
8148 package set might look like:
8151 ;; Manifest for three packages.
8152 (specifications->manifest '("gcc-toolchain" "make" "git"))
8155 Once you have that manifest, you can pass it, for example, to
8156 @command{guix package} to install just those three packages to your
8157 profile (@pxref{profile-manifest, @option{-m} option of @command{guix
8161 guix package -m manifest.scm
8165 ... or you can pass it to @command{guix shell} (@pxref{shell-manifest,
8166 @command{-m} option of @command{guix shell}}) to spawn an ephemeral
8170 guix shell -m manifest.scm
8174 ... or you can pass it to @command{guix pack} in pretty much the same
8175 way (@pxref{pack-manifest, @option{-m} option of @command{guix pack}}).
8176 You can store the manifest under version control, share it with others
8177 so they can easily get set up, etc.
8179 But how do you write your first manifest? To get started, maybe you'll
8180 want to write a manifest that mirrors what you already have in a
8181 profile. Rather than start from a blank page, @command{guix package}
8182 can generate a manifest for you (@pxref{export-manifest, @command{guix
8183 package --export-manifest}}):
8186 # Write to 'manifest.scm' a manifest corresponding to the
8187 # default profile, ~/.guix-profile.
8188 guix package --export-manifest > manifest.scm
8191 Or maybe you'll want to ``translate'' command-line arguments into a
8192 manifest. In that case, @command{guix shell} can help
8193 (@pxref{shell-export-manifest, @command{guix shell --export-manifest}}):
8196 # Write a manifest for the packages specified on the command line.
8197 guix shell --export-manifest gcc-toolchain make git > manifest.scm
8200 In both cases, the @option{--export-manifest} option tries hard to
8201 generate a faithful manifest; in particular, it takes package
8202 transformation options into account (@pxref{Package Transformation
8206 Manifests are @emph{symbolic}: they refer to packages of the channels
8207 @emph{currently in use} (@pxref{Channels}). In the example above,
8208 @code{gcc-toolchain} might refer to version 11 today, but it might refer
8209 to version 13 two years from now.
8211 If you want to ``pin'' your software environment to specific package
8212 versions and variants, you need an additional piece of information: the
8213 list of channel revisions in use, as returned by @command{guix
8214 describe}. @xref{Replicating Guix}, for more information.
8217 Once you've obtained your first manifest, perhaps you'll want to
8218 customize it. Since your manifest is code, you now have access to all
8219 the Guix programming interfaces!
8221 Let's assume you want a manifest to deploy a custom variant of GDB, the
8222 GNU Debugger, that does not depend on Guile, together with another
8223 package. Building on the example seen in the previous section
8224 (@pxref{Defining Package Variants}), you can write a manifest along
8228 (use-modules (guix packages)
8229 (gnu packages gdb) ;for 'gdb'
8230 (gnu packages version-control)) ;for 'git'
8232 ;; Define a variant of GDB without a dependency on Guile.
8233 (define gdb-sans-guile
8236 (inputs (modify-inputs (package-inputs gdb)
8237 (delete "guile")))))
8239 ;; Return a manifest containing that one package plus Git.
8240 (packages->manifest (list gdb-sans-guile git))
8243 Note that in this example, the manifest directly refers to the
8244 @code{gdb} and @code{git} variables, which are bound to a @code{package}
8245 object (@pxref{package Reference}), instead of calling
8246 @code{specifications->manifest} to look up packages by name as we did
8247 before. The @code{use-modules} form at the top lets us access the core
8248 package interface (@pxref{Defining Packages}) and the modules that
8249 define @code{gdb} and @code{git} (@pxref{Package Modules}). Seamlessly,
8250 we're weaving all this together---the possibilities are endless, unleash
8253 The data type for manifests as well as supporting procedures are defined
8254 in the @code{(guix profiles)} module, which is automatically available
8255 to code passed to @option{-m}. The reference follows.
8257 @deftp {Data Type} manifest
8258 Data type representing a manifest.
8260 It currently has one field:
8264 This must be a list of @code{manifest-entry} records---see below.
8268 @deftp {Data Type} manifest-entry
8269 Data type representing a manifest entry. A manifest entry contains
8270 essential metadata: a name and version string, the object (usually a
8271 package) for that entry, the desired output (@pxref{Packages with
8272 Multiple Outputs}), and a number of optional pieces of information
8275 Most of the time, you won't build a manifest entry directly; instead,
8276 you will pass a package to @code{package->manifest-entry}, described
8277 below. In some unusual cases though, you might want to create manifest
8278 entries for things that are @emph{not} packages, as in this example:
8281 ;; Manually build a single manifest entry for a non-package object.
8282 (let ((hello (program-file "hello" #~(display "Hi!"))))
8287 (computed-file "hello-directory"
8288 #~(let ((bin (string-append #$output "/bin")))
8289 (mkdir #$output) (mkdir bin)
8291 (string-append bin "/hello")))))))
8294 The available fields are the following:
8298 @itemx @code{version}
8299 Name and version string for this entry.
8302 A package or other file-like object (@pxref{G-Expressions, file-like
8305 @item @code{output} (default: @code{"out"})
8306 Output of @code{item} to use, in case @code{item} has multiple outputs
8307 (@pxref{Packages with Multiple Outputs}).
8309 @item @code{dependencies} (default: @code{'()})
8310 List of manifest entries this entry depends on. When building a
8311 profile, dependencies are added to the profile.
8313 Typically, the propagated inputs of a package (@pxref{package Reference,
8314 @code{propagated-inputs}}) end up having a corresponding manifest entry
8315 in among the dependencies of the package's own manifest entry.
8317 @item @code{search-paths} (default: @code{'()})
8318 The list of search path specifications honored by this entry
8319 (@pxref{Search Paths}).
8321 @item @code{properties} (default: @code{'()})
8322 List of symbol/value pairs. When building a profile, those properties
8325 This can be used to piggyback additional metadata---e.g., the
8326 transformations applied to a package (@pxref{Package Transformation
8329 @item @code{parent} (default: @code{(delay #f)})
8330 A promise pointing to the ``parent'' manifest entry.
8332 This is used as a hint to provide context when reporting an error
8333 related to a manifest entry coming from a @code{dependencies} field.
8337 @deffn {Scheme Procedure} concatenate-manifests @var{lst}
8338 Concatenate the manifests listed in @var{lst} and return the resulting
8342 @c TODO: <manifest-pattern>, manifest-lookup, manifest-remove, etc.
8344 @deffn {Scheme Procedure} package->manifest-entry @var{package} @
8345 [@var{output}] [#:properties]
8346 Return a manifest entry for the @var{output} of package @var{package},
8347 where @var{output} defaults to @code{"out"}, and with the given
8348 @var{properties}. By default @var{properties} is the empty list or, if
8349 one or more package transformations were applied to @var{package}, it is
8350 an association list representing those transformations, suitable as an
8351 argument to @code{options->transformation} (@pxref{Defining Package
8352 Variants, @code{options->transformation}}).
8354 The code snippet below builds a manifest with an entry for the default
8355 output and the @code{send-email} output of the @code{git} package:
8358 (use-modules (gnu packages version-control))
8360 (manifest (list (package->manifest-entry git)
8361 (package->manifest-entry git "send-email")))
8365 @deffn {Scheme Procedure} packages->manifest @var{packages}
8366 Return a list of manifest entries, one for each item listed in
8367 @var{packages}. Elements of @var{packages} can be either package
8368 objects or package/string tuples denoting a specific output of a
8371 Using this procedure, the manifest above may be rewritten more
8375 (use-modules (gnu packages version-control))
8377 (packages->manifest (list git `(,git "send-email")))
8381 @anchor{package-development-manifest}
8382 @deffn {Scheme Procedure} package->development-manifest @var{package} @
8383 [@var{system}] [#:target]
8384 Return a manifest for the @dfn{development inputs} of @var{package} for
8385 @var{system}, optionally when cross-compiling to @var{target}.
8386 Development inputs include both explicit and implicit inputs of
8389 Like the @option{-D} option of @command{guix shell}
8390 (@pxref{shell-development-option, @command{guix shell -D}}), the
8391 resulting manifest describes the environment in which one can develop
8392 @var{package}. For example, suppose you're willing to set up a
8393 development environment for Inkscape, with the addition of Git for
8394 version control; you can describe that ``bill of materials'' with the
8398 (use-modules (gnu packages inkscape) ;for 'inkscape'
8399 (gnu packages version-control)) ;for 'git'
8401 (concatenate-manifests
8402 (list (package->development-manifest inkscape)
8403 (packages->manifest (list git))))
8406 In this example, the development manifest that
8407 @code{package->development-manifest} returns includes the compiler
8408 (GCC), the many supporting libraries (Boost, GLib, GTK, etc.), and a
8409 couple of additional development tools---these are the dependencies
8410 @command{guix show inkscape} lists.
8413 @c TODO: Move (gnu packages) interface to a section of its own.
8415 Last, the @code{(gnu packages)} module provides higher-level facilities
8416 to build manifests. In particular, it lets you look up packages by
8419 @deffn {Scheme Procedure} specifications->manifest @var{specs}
8420 Given @var{specs}, a list of specifications such as @code{"emacs@@25.2"}
8421 or @code{"guile:debug"}, return a manifest. Specs have the format that
8422 command-line tools such as @command{guix install} and @command{guix
8423 package} understand (@pxref{Invoking guix package}).
8425 As an example, it lets you rewrite the Git manifest that we saw earlier
8429 (specifications->manifest '("git" "git:send-email"))
8432 Notice that we do not need to worry about @code{use-modules}, importing
8433 the right set of modules, and referring to the right variables.
8434 Instead, we directly refer to packages in the same way as on the command
8435 line, which can often be more convenient.
8438 @c TODO: specifications->package, etc.
8442 @section Build Systems
8444 @cindex build system
8445 Each package definition specifies a @dfn{build system} and arguments for
8446 that build system (@pxref{Defining Packages}). This @code{build-system}
8447 field represents the build procedure of the package, as well as implicit
8448 dependencies of that build procedure.
8450 Build systems are @code{<build-system>} objects. The interface to
8451 create and manipulate them is provided by the @code{(guix build-system)}
8452 module, and actual build systems are exported by specific modules.
8454 @cindex bag (low-level package representation)
8455 Under the hood, build systems first compile package objects to
8456 @dfn{bags}. A @dfn{bag} is like a package, but with less
8457 ornamentation---in other words, a bag is a lower-level representation of
8458 a package, which includes all the inputs of that package, including some
8459 that were implicitly added by the build system. This intermediate
8460 representation is then compiled to a derivation (@pxref{Derivations}).
8461 The @code{package-with-c-toolchain} is an example of a way to change the
8462 implicit inputs that a package's build system pulls in (@pxref{package
8463 Reference, @code{package-with-c-toolchain}}).
8465 Build systems accept an optional list of @dfn{arguments}. In package
8466 definitions, these are passed @i{via} the @code{arguments} field
8467 (@pxref{Defining Packages}). They are typically keyword arguments
8468 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
8469 Guile Reference Manual}). The value of these arguments is usually
8470 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
8471 by the daemon (@pxref{Derivations}).
8473 The main build system is @code{gnu-build-system}, which implements the
8474 standard build procedure for GNU and many other packages. It
8475 is provided by the @code{(guix build-system gnu)} module.
8477 @defvr {Scheme Variable} gnu-build-system
8478 @code{gnu-build-system} represents the GNU Build System, and variants
8479 thereof (@pxref{Configuration, configuration and makefile conventions,,
8480 standards, GNU Coding Standards}).
8482 @cindex build phases
8483 In a nutshell, packages using it are configured, built, and installed with
8484 the usual @code{./configure && make && make check && make install}
8485 command sequence. In practice, a few additional steps are often needed.
8486 All these steps are split up in separate @dfn{phases}.
8487 @xref{Build Phases}, for more info on build phases and ways to customize
8490 In addition, this build system ensures that the ``standard'' environment
8491 for GNU packages is available. This includes tools such as GCC, libc,
8492 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
8493 build-system gnu)} module for a complete list). We call these the
8494 @dfn{implicit inputs} of a package, because package definitions do not
8495 have to mention them.
8497 This build system supports a number of keyword arguments, which can be
8498 passed @i{via} the @code{arguments} field of a package. Here are some
8499 of the main parameters:
8503 This argument specifies build-side code that evaluates to an alist of
8504 build phases. @xref{Build Phases}, for more information.
8506 @item #:configure-flags
8507 This is a list of flags (strings) passed to the @command{configure}
8508 script. @xref{Defining Packages}, for an example.
8511 This list of strings contains flags passed as arguments to
8512 @command{make} invocations in the @code{build}, @code{check}, and
8513 @code{install} phases.
8515 @item #:out-of-source?
8516 This Boolean, @code{#f} by default, indicates whether to run builds in a
8517 build directory separate from the source tree.
8519 When it is true, the @code{configure} phase creates a separate build
8520 directory, changes to that directory, and runs the @code{configure}
8521 script from there. This is useful for packages that require it, such as
8525 This Boolean, @code{#t} by default, indicates whether the @code{check}
8526 phase should run the package's test suite.
8529 This string, @code{"check"} by default, gives the name of the makefile
8530 target used by the @code{check} phase.
8532 @item #:parallel-build?
8533 @itemx #:parallel-tests?
8534 These Boolean values specify whether to build, respectively run the test
8535 suite, in parallel, with the @code{-j} flag of @command{make}. When
8536 they are true, @code{make} is passed @code{-j@var{n}}, where @var{n} is
8537 the number specified as the @option{--cores} option of
8538 @command{guix-daemon} or that of the @command{guix} client command
8539 (@pxref{Common Build Options, @option{--cores}}).
8541 @cindex RUNPATH, validation
8542 @item #:validate-runpath?
8543 This Boolean, @code{#t} by default, determines whether to ``validate''
8544 the @code{RUNPATH} of ELF binaries (@code{.so} shared libraries as well
8545 as executables) previously installed by the @code{install} phase.
8546 @xref{phase-validate-runpath, the @code{validate-runpath} phase}, for
8549 @item #:substitutable?
8550 This Boolean, @code{#t} by default, tells whether the package outputs
8551 should be substitutable---i.e., whether users should be able to obtain
8552 substitutes for them instead of building locally (@pxref{Substitutes}).
8554 @item #:allowed-references
8555 @itemx #:disallowed-references
8556 When true, these arguments must be a list of dependencies that must not
8557 appear among the references of the build results. If, upon build
8558 completion, some of these references are retained, the build process
8561 This is useful to ensure that a package does not erroneously keep a
8562 reference to some of it build-time inputs, in cases where doing so
8563 would, for example, unnecessarily increase its size (@pxref{Invoking
8567 Most other build systems support these keyword arguments.
8570 Other @code{<build-system>} objects are defined to support other
8571 conventions and tools used by free software packages. They inherit most
8572 of @code{gnu-build-system}, and differ mainly in the set of inputs
8573 implicitly added to the build process, and in the list of phases
8574 executed. Some of these build systems are listed below.
8576 @defvr {Scheme Variable} ant-build-system
8577 This variable is exported by @code{(guix build-system ant)}. It
8578 implements the build procedure for Java packages that can be built with
8579 @url{https://ant.apache.org/, Ant build tool}.
8581 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
8582 provided by the @code{icedtea} package to the set of inputs. Different
8583 packages can be specified with the @code{#:ant} and @code{#:jdk}
8584 parameters, respectively.
8586 When the original package does not provide a suitable Ant build file,
8587 the parameter @code{#:jar-name} can be used to generate a minimal Ant
8588 build file @file{build.xml} with tasks to build the specified jar
8589 archive. In this case the parameter @code{#:source-dir} can be used to
8590 specify the source sub-directory, defaulting to ``src''.
8592 The @code{#:main-class} parameter can be used with the minimal ant
8593 buildfile to specify the main class of the resulting jar. This makes the
8594 jar file executable. The @code{#:test-include} parameter can be used to
8595 specify the list of junit tests to run. It defaults to
8596 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
8597 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
8598 because abstract classes cannot be run as tests.
8600 The parameter @code{#:build-target} can be used to specify the Ant task
8601 that should be run during the @code{build} phase. By default the
8602 ``jar'' task will be run.
8606 @defvr {Scheme Variable} android-ndk-build-system
8607 @cindex Android distribution
8608 @cindex Android NDK build system
8609 This variable is exported by @code{(guix build-system android-ndk)}. It
8610 implements a build procedure for Android NDK (native development kit)
8611 packages using a Guix-specific build process.
8613 The build system assumes that packages install their public interface
8614 (header) files to the subdirectory @file{include} of the @code{out} output and
8615 their libraries to the subdirectory @file{lib} the @code{out} output.
8617 It's also assumed that the union of all the dependencies of a package
8618 has no conflicting files.
8620 For the time being, cross-compilation is not supported - so right now
8621 the libraries and header files are assumed to be host tools.
8625 @defvr {Scheme Variable} asdf-build-system/source
8626 @defvrx {Scheme Variable} asdf-build-system/sbcl
8627 @defvrx {Scheme Variable} asdf-build-system/ecl
8629 These variables, exported by @code{(guix build-system asdf)}, implement
8630 build procedures for Common Lisp packages using
8631 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
8632 definition facility for Common Lisp programs and libraries.
8634 The @code{asdf-build-system/source} system installs the packages in
8635 source form, and can be loaded using any common lisp implementation, via
8636 ASDF@. The others, such as @code{asdf-build-system/sbcl}, install binary
8637 systems in the format which a particular implementation understands.
8638 These build systems can also be used to produce executable programs, or
8639 lisp images which contain a set of packages pre-loaded.
8641 The build system uses naming conventions. For binary packages, the
8642 package name should be prefixed with the lisp implementation, such as
8643 @code{sbcl-} for @code{asdf-build-system/sbcl}.
8645 Additionally, the corresponding source package should be labeled using
8646 the same convention as python packages (see @ref{Python Modules}), using
8647 the @code{cl-} prefix.
8649 In order to create executable programs and images, the build-side
8650 procedures @code{build-program} and @code{build-image} can be used.
8651 They should be called in a build phase after the
8652 @code{create-asdf-configuration} phase, so that the system which was
8653 just built can be used within the resulting image. @code{build-program}
8654 requires a list of Common Lisp expressions to be passed as the
8655 @code{#:entry-program} argument.
8657 By default, all the @file{.asd} files present in the sources are read to
8658 find system definitions. The @code{#:asd-files} parameter can be used
8659 to specify the list of @file{.asd} files to read. Furthermore, if the
8660 package defines a system for its tests in a separate file, it will be
8661 loaded before the tests are run if it is specified by the
8662 @code{#:test-asd-file} parameter. If it is not set, the files
8663 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
8664 and @code{test.asd} will be tried if they exist.
8666 If for some reason the package must be named in a different way than the
8667 naming conventions suggest, or if several systems must be compiled, the
8668 @code{#:asd-systems} parameter can be used to specify the list of system
8673 @defvr {Scheme Variable} cargo-build-system
8674 @cindex Rust programming language
8675 @cindex Cargo (Rust build system)
8676 This variable is exported by @code{(guix build-system cargo)}. It
8677 supports builds of packages using Cargo, the build tool of the
8678 @uref{https://www.rust-lang.org, Rust programming language}.
8680 It adds @code{rustc} and @code{cargo} to the set of inputs.
8681 A different Rust package can be specified with the @code{#:rust} parameter.
8683 Regular cargo dependencies should be added to the package definition similarly
8684 to other packages; those needed only at build time to native-inputs, others to
8685 inputs. If you need to add source-only crates then you should add them to via
8686 the @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
8687 spec can be a package or a source definition. Note that the spec must
8688 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
8689 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
8690 should be added to the package definition via the
8691 @code{#:cargo-development-inputs} parameter.
8693 In its @code{configure} phase, this build system will make any source inputs
8694 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
8695 parameters available to cargo. It will also remove an included
8696 @code{Cargo.lock} file to be recreated by @code{cargo} during the
8697 @code{build} phase. The @code{package} phase will run @code{cargo package}
8698 to create a source crate for future use. The @code{install} phase installs
8699 the binaries defined by the crate. Unless @code{install-source? #f} is
8700 defined it will also install a source crate repository of itself and unpacked
8701 sources, to ease in future hacking on rust packages.
8704 @defvr {Scheme Variable} chicken-build-system
8705 This variable is exported by @code{(guix build-system chicken)}. It
8706 builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
8707 ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
8708 gets compiled by a C compiler, in this case GCC.
8710 This build system adds @code{chicken} to the package inputs, as well as
8711 the packages of @code{gnu-build-system}.
8713 The build system can't (yet) deduce the egg's name automatically, so just like
8714 with @code{go-build-system} and its @code{#:import-path}, you should define
8715 @code{#:egg-name} in the package's @code{arguments} field.
8717 For example, if you are packaging the @code{srfi-1} egg:
8720 (arguments '(#:egg-name "srfi-1"))
8723 Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
8724 because CHICKEN doesn't embed absolute references in compiled eggs.
8725 Test dependencies should go to @code{native-inputs}, as usual.
8728 @defvr {Scheme Variable} copy-build-system
8729 This variable is exported by @code{(guix build-system copy)}. It
8730 supports builds of simple packages that don't require much compiling,
8731 mostly just moving files around.
8733 It adds much of the @code{gnu-build-system} packages to the set of
8734 inputs. Because of this, the @code{copy-build-system} does not require
8735 all the boilerplate code often needed for the
8736 @code{trivial-build-system}.
8738 To further simplify the file installation process, an
8739 @code{#:install-plan} argument is exposed to let the packager specify
8740 which files go where. The install plan is a list of @code{(@var{source}
8741 @var{target} [@var{filters}])}. @var{filters} are optional.
8744 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
8746 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
8747 @item Otherwise install @var{source} as @var{target}.
8750 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
8751 the trailing slash of @var{target} is implied with the same meaning
8754 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
8755 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
8756 @code{#:exclude-regexp}, only select files are installed depending on
8757 the filters. Each filters is specified by a list of strings.
8759 @item With @code{#:include}, install all the files which the path suffix matches
8760 at least one of the elements in the given list.
8761 @item With @code{#:include-regexp}, install all the files which the
8762 subpaths match at least one of the regular expressions in the given
8764 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
8765 are the complement of their inclusion counterpart. Without @code{#:include} flags,
8766 install all files but those matching the exclusion filters.
8767 If both inclusions and exclusions are specified, the exclusions are done
8768 on top of the inclusions.
8771 In all cases, the paths relative to @var{source} are preserved within
8778 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
8779 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
8780 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
8781 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
8782 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
8783 @file{share/my-app/sub/file}.
8784 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
8785 @file{share/my-app/file}.
8790 @cindex Clojure (programming language)
8791 @cindex simple Clojure build system
8792 @defvr {Scheme Variable} clojure-build-system
8793 This variable is exported by @code{(guix build-system clojure)}. It implements
8794 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
8795 using plain old @code{compile} in Clojure. Cross-compilation is not supported
8798 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
8799 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
8800 @code{#:zip} parameters, respectively.
8802 A list of source directories, test directories and jar names can be specified
8803 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
8804 parameters, respectively. Compile directory and main class can be specified
8805 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
8806 Other parameters are documented below.
8808 This build system is an extension of @code{ant-build-system}, but with the
8809 following phases changed:
8814 This phase calls @code{compile} in Clojure to compile source files and runs
8815 @command{jar} to create jars from both source files and compiled files
8816 according to the include list and exclude list specified in
8817 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
8818 has priority over the include list. These lists consist of symbols
8819 representing Clojure libraries or the special keyword @code{#:all} representing
8820 all Clojure libraries found under the source directories. The parameter
8821 @code{#:omit-source?} decides if source should be included into the jars.
8824 This phase runs tests according to the include list and exclude list specified
8825 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
8826 meanings are analogous to that of @code{#:aot-include} and
8827 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
8828 stands for all Clojure libraries found under the test directories. The
8829 parameter @code{#:tests?} decides if tests should be run.
8832 This phase installs all jars built previously.
8835 Apart from the above, this build system also contains an additional phase:
8840 This phase installs all top-level files with base name matching
8841 @code{%doc-regex}. A different regex can be specified with the
8842 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
8843 directories specified in @code{#:doc-dirs} are installed as well.
8847 @defvr {Scheme Variable} cmake-build-system
8848 This variable is exported by @code{(guix build-system cmake)}. It
8849 implements the build procedure for packages using the
8850 @url{https://www.cmake.org, CMake build tool}.
8852 It automatically adds the @code{cmake} package to the set of inputs.
8853 Which package is used can be specified with the @code{#:cmake}
8856 The @code{#:configure-flags} parameter is taken as a list of flags
8857 passed to the @command{cmake} command. The @code{#:build-type}
8858 parameter specifies in abstract terms the flags passed to the compiler;
8859 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
8860 debugging information''), which roughly means that code is compiled with
8861 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
8864 @defvr {Scheme Variable} dune-build-system
8865 This variable is exported by @code{(guix build-system dune)}. It
8866 supports builds of packages using @uref{https://dune.build/, Dune}, a build
8867 tool for the OCaml programming language. It is implemented as an extension
8868 of the @code{ocaml-build-system} which is described below. As such, the
8869 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
8872 It automatically adds the @code{dune} package to the set of inputs.
8873 Which package is used can be specified with the @code{#:dune}
8876 There is no @code{configure} phase because dune packages typically don't
8877 need to be configured. The @code{#:build-flags} parameter is taken as a
8878 list of flags passed to the @code{dune} command during the build.
8880 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
8881 command instead of the more recent @code{dune} command while building
8882 a package. Its default value is @code{#f}.
8884 The @code{#:package} parameter can be passed to specify a package name, which
8885 is useful when a package contains multiple packages and you want to build
8886 only one of them. This is equivalent to passing the @code{-p} argument to
8891 @defvr {Scheme variable} elm-build-system
8892 This variable is exported by @code{(guix build-system elm)}. It implements a
8893 build procedure for @url{https://elm-lang.org, Elm} packages similar to
8896 The build system adds an Elm compiler package to the set of inputs. The
8897 default compiler package (currently @code{elm-sans-reactor}) can be overridden
8898 using the @code{#:elm} argument. Additionally, Elm packages needed by the
8899 build system itself are added as implicit inputs if they are not already
8900 present: to suppress this behavior, use the
8901 @code{#:implicit-elm-package-inputs?} argument, which is primarily useful for
8904 The @code{"dependencies"} and @code{"test-dependencies"} in an Elm package's
8905 @file{elm.json} file correspond to @code{propagated-inputs} and @code{inputs},
8908 Elm requires a particular structure for package names: @pxref{Elm Packages}
8909 for more details, including utilities provided by @code{(guix build-system
8912 There are currently a few noteworthy limitations to @code{elm-build-system}:
8916 The build system is focused on @dfn{packages} in the Elm sense of the word:
8917 Elm @dfn{projects} which declare @code{@{ "type": "package" @}} in their
8918 @file{elm.json} files. Using @code{elm-build-system} to build Elm
8919 @dfn{applications} (which declare @code{@{ "type": "application" @}}) is
8920 possible, but requires ad-hoc modifications to the build phases. For
8921 examples, see the definitions of the @code{elm-todomvc} example application and
8922 the @code{elm} package itself (because the front-end for the
8923 @samp{elm reactor} command is an Elm application).
8926 Elm supports multiple versions of a package coexisting simultaneously under
8927 @env{ELM_HOME}, but this does not yet work well with @code{elm-build-system}.
8928 This limitation primarily affects Elm applications, because they specify
8929 exact versions for their dependencies, whereas Elm packages specify supported
8930 version ranges. As a workaround, the example applications mentioned above use
8931 the @code{patch-application-dependencies} procedure provided by
8932 @code{(guix build elm-build-system)} to rewrite their @file{elm.json} files to
8933 refer to the package versions actually present in the build environment.
8934 Alternatively, Guix package transformations (@pxref{Defining Package
8935 Variants}) could be used to rewrite an application's entire dependency graph.
8938 We are not yet able to run tests for Elm projects because neither
8939 @url{https://github.com/mpizenberg/elm-test-rs, @command{elm-test-rs}} nor the
8940 Node.js-based @url{https://github.com/rtfeldman/node-test-runner,
8941 @command{elm-test}} runner has been packaged for Guix yet.
8945 @defvr {Scheme Variable} go-build-system
8946 This variable is exported by @code{(guix build-system go)}. It
8947 implements a build procedure for Go packages using the standard
8948 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
8949 Go build mechanisms}.
8951 The user is expected to provide a value for the key @code{#:import-path}
8952 and, in some cases, @code{#:unpack-path}. The
8953 @url{https://golang.org/doc/code.html#ImportPaths, import path}
8954 corresponds to the file system path expected by the package's build
8955 scripts and any referring packages, and provides a unique way to
8956 refer to a Go package. It is typically based on a combination of the
8957 package source code's remote URI and file system hierarchy structure. In
8958 some cases, you will need to unpack the package's source code to a
8959 different directory structure than the one indicated by the import path,
8960 and @code{#:unpack-path} should be used in such cases.
8962 Packages that provide Go libraries should install their source code into
8963 the built output. The key @code{#:install-source?}, which defaults to
8964 @code{#t}, controls whether or not the source code is installed. It can
8965 be set to @code{#f} for packages that only provide executable files.
8967 Packages can be cross-built, and if a specific architecture or operating
8968 system is desired then the keywords @code{#:goarch} and @code{#:goos}
8969 can be used to force the package to be built for that architecture and
8970 operating system. The combinations known to Go can be found
8971 @url{"https://golang.org/doc/install/source#environment", in their
8975 @defvr {Scheme Variable} glib-or-gtk-build-system
8976 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
8977 is intended for use with packages making use of GLib or GTK+.
8979 This build system adds the following two phases to the ones defined by
8980 @code{gnu-build-system}:
8983 @item glib-or-gtk-wrap
8984 The phase @code{glib-or-gtk-wrap} ensures that programs in
8985 @file{bin/} are able to find GLib ``schemas'' and
8986 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
8987 modules}. This is achieved by wrapping the programs in launch scripts
8988 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
8989 environment variables.
8991 It is possible to exclude specific package outputs from that wrapping
8992 process by listing their names in the
8993 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
8994 when an output is known not to contain any GLib or GTK+ binaries, and
8995 where wrapping would gratuitously add a dependency of that output on
8998 @item glib-or-gtk-compile-schemas
8999 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
9000 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
9001 GSettings schemas} of GLib are compiled. Compilation is performed by the
9002 @command{glib-compile-schemas} program. It is provided by the package
9003 @code{glib:bin} which is automatically imported by the build system.
9004 The @code{glib} package providing @command{glib-compile-schemas} can be
9005 specified with the @code{#:glib} parameter.
9008 Both phases are executed after the @code{install} phase.
9011 @defvr {Scheme Variable} guile-build-system
9012 This build system is for Guile packages that consist exclusively of Scheme
9013 code and that are so lean that they don't even have a makefile, let alone a
9014 @file{configure} script. It compiles Scheme code using @command{guild
9015 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
9016 installs the @file{.scm} and @file{.go} files in the right place. It also
9017 installs documentation.
9019 This build system supports cross-compilation by using the
9020 @option{--target} option of @samp{guild compile}.
9022 Packages built with @code{guile-build-system} must provide a Guile package in
9023 their @code{native-inputs} field.
9026 @defvr {Scheme Variable} julia-build-system
9027 This variable is exported by @code{(guix build-system julia)}. It
9028 implements the build procedure used by @uref{https://julialang.org/,
9029 julia} packages, which essentially is similar to running @samp{julia -e
9030 'using Pkg; Pkg.add(package)'} in an environment where
9031 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
9032 Tests are run by calling @code{/test/runtests.jl}.
9034 The Julia package name and uuid is read from the file
9035 @file{Project.toml}. These values can be overridden by passing the
9036 argument @code{#:julia-package-name} (which must be correctly
9037 capitalized) or @code{#:julia-package-uuid}.
9039 Julia packages usually manage their binary dependencies via
9040 @code{JLLWrappers.jl}, a Julia package that creates a module (named
9041 after the wrapped library followed by @code{_jll.jl}.
9043 To add the binary path @code{_jll.jl} packages, you need to patch the
9044 files under @file{src/wrappers/}, replacing the call to the macro
9045 @code{JLLWrappers.@@generate_wrapper_header}, adding as a second
9046 argument containing the store path the binary.
9048 As an example, in the MbedTLS Julia package, we add a build phase
9049 (@pxref{Build Phases}) to insert the absolute file name of the wrapped
9053 (add-after 'unpack 'override-binary-path
9054 (lambda* (#:key inputs #:allow-other-keys)
9055 (for-each (lambda (wrapper)
9056 (substitute* wrapper
9057 (("generate_wrapper_header.*")
9059 "generate_wrapper_header(\"MbedTLS\", \""
9060 (assoc-ref inputs "mbedtls-apache") "\")\n"))))
9061 ;; There's a Julia file for each platform, override them all.
9062 (find-files "src/wrappers/" "\\.jl$"))))
9065 Some older packages that aren't using @file{Project.toml} yet, will
9066 require this file to be created, too. It is internally done if the
9067 arguments @code{#:julia-package-name} and @code{#:julia-package-uuid}
9071 @defvr {Scheme Variable} maven-build-system
9072 This variable is exported by @code{(guix build-system maven)}. It implements
9073 a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
9074 is a dependency and lifecycle management tool for Java. A user of Maven
9075 specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
9076 When Maven does not have one of the dependencies or plugins in its repository,
9077 it will download them and use them to build the package.
9079 The maven build system ensures that maven will not try to download any
9080 dependency by running in offline mode. Maven will fail if a dependency is
9081 missing. Before running Maven, the @file{pom.xml} (and subprojects) are
9082 modified to specify the version of dependencies and plugins that match the
9083 versions available in the guix build environment. Dependencies and plugins
9084 must be installed in the fake maven repository at @file{lib/m2}, and are
9085 symlinked into a proper repository before maven is run. Maven is instructed
9086 to use that repository for the build and installs built artifacts there.
9087 Changed files are copied to the @file{lib/m2} directory of the package output.
9089 You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
9090 or let the build system use the default @file{pom.xml} file in the sources.
9092 In case you need to specify a dependency's version manually, you can use the
9093 @code{#:local-packages} argument. It takes an association list where the key
9094 is the groupId of the package and its value is an association list where the
9095 key is the artifactId of the package and its value is the version you want to
9096 override in the @file{pom.xml}.
9098 Some packages use dependencies or plugins that are not useful at runtime nor
9099 at build time in Guix. You can alter the @file{pom.xml} file to remove them
9100 using the @code{#:exclude} argument. Its value is an association list where
9101 the key is the groupId of the plugin or dependency you want to remove, and
9102 the value is a list of artifactId you want to remove.
9104 You can override the default @code{jdk} and @code{maven} packages with the
9105 corresponding argument, @code{#:jdk} and @code{#:maven}.
9107 The @code{#:maven-plugins} argument is a list of maven plugins used during
9108 the build, with the same format as the @code{inputs} fields of the package
9109 declaration. Its default value is @code{(default-maven-plugins)} which is
9113 @defvr {Scheme Variable} minetest-mod-build-system
9114 This variable is exported by @code{(guix build-system minetest)}. It
9115 implements a build procedure for @uref{https://www.minetest.net, Minetest}
9116 mods, which consists of copying Lua code, images and other resources to
9117 the location Minetest searches for mods. The build system also minimises
9118 PNG images and verifies that Minetest can load the mod without errors.
9121 @defvr {Scheme Variable} minify-build-system
9122 This variable is exported by @code{(guix build-system minify)}. It
9123 implements a minification procedure for simple JavaScript packages.
9125 It adds @code{uglify-js} to the set of inputs and uses it to compress
9126 all JavaScript files in the @file{src} directory. A different minifier
9127 package can be specified with the @code{#:uglify-js} parameter, but it
9128 is expected that the package writes the minified code to the standard
9131 When the input JavaScript files are not all located in the @file{src}
9132 directory, the parameter @code{#:javascript-files} can be used to
9133 specify a list of file names to feed to the minifier.
9136 @defvr {Scheme Variable} ocaml-build-system
9137 This variable is exported by @code{(guix build-system ocaml)}. It implements
9138 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
9139 of choosing the correct set of commands to run for each package. OCaml
9140 packages can expect many different commands to be run. This build system will
9143 When the package has a @file{setup.ml} file present at the top-level, it will
9144 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
9145 @code{ocaml setup.ml -install}. The build system will assume that this file
9146 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
9147 care of setting the prefix and enabling tests if they are not disabled. You
9148 can pass configure and build flags with the @code{#:configure-flags} and
9149 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
9150 set of flags used to enable tests. The @code{#:use-make?} key can be used to
9151 bypass this system in the build and install phases.
9153 When the package has a @file{configure} file, it is assumed that it is a
9154 hand-made configure script that requires a different argument format than
9155 in the @code{gnu-build-system}. You can add more flags with the
9156 @code{#:configure-flags} key.
9158 When the package has a @file{Makefile} file (or @code{#:use-make?} is
9159 @code{#t}), it will be used and more flags can be passed to the build and
9160 install phases with the @code{#:make-flags} key.
9162 Finally, some packages do not have these files and use a somewhat standard
9163 location for its build system. In that case, the build system will run
9164 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
9165 providing the path to the required findlib module. Additional flags can
9166 be passed via the @code{#:build-flags} key. Install is taken care of by
9167 @command{opam-installer}. In this case, the @code{opam} package must
9168 be added to the @code{native-inputs} field of the package definition.
9170 Note that most OCaml packages assume they will be installed in the same
9171 directory as OCaml, which is not what we want in guix. In particular, they
9172 will install @file{.so} files in their module's directory, which is usually
9173 fine because it is in the OCaml compiler directory. In guix though, these
9174 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
9175 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
9176 @file{.so} libraries should be installed.
9179 @defvr {Scheme Variable} python-build-system
9180 This variable is exported by @code{(guix build-system python)}. It
9181 implements the more or less standard build procedure used by Python
9182 packages, which consists in running @code{python setup.py build} and
9183 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
9185 For packages that install stand-alone Python programs under @code{bin/},
9186 it takes care of wrapping these programs so that their
9187 @env{GUIX_PYTHONPATH} environment variable points to all the Python
9188 libraries they depend on.
9190 Which Python package is used to perform the build can be specified with
9191 the @code{#:python} parameter. This is a useful way to force a package
9192 to be built for a specific version of the Python interpreter, which
9193 might be necessary if the package is only compatible with a single
9194 interpreter version.
9196 By default guix calls @code{setup.py} under control of
9197 @code{setuptools}, much like @command{pip} does. Some packages are not
9198 compatible with setuptools (and pip), thus you can disable this by
9199 setting the @code{#:use-setuptools?} parameter to @code{#f}.
9201 If a @code{"python"} output is available, the package is installed into it
9202 instead of the default @code{"out"} output. This is useful for packages that
9203 include a Python package as only a part of the software, and thus want to
9204 combine the phases of @code{python-build-system} with another build system.
9205 Python bindings are a common usecase.
9209 @defvr {Scheme Variable} perl-build-system
9210 This variable is exported by @code{(guix build-system perl)}. It
9211 implements the standard build procedure for Perl packages, which either
9212 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
9213 followed by @code{Build} and @code{Build install}; or in running
9214 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
9215 @code{make} and @code{make install}, depending on which of
9216 @code{Build.PL} or @code{Makefile.PL} is present in the package
9217 distribution. Preference is given to the former if both @code{Build.PL}
9218 and @code{Makefile.PL} exist in the package distribution. This
9219 preference can be reversed by specifying @code{#t} for the
9220 @code{#:make-maker?} parameter.
9222 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
9223 passes flags specified by the @code{#:make-maker-flags} or
9224 @code{#:module-build-flags} parameter, respectively.
9226 Which Perl package is used can be specified with @code{#:perl}.
9229 @defvr {Scheme Variable} renpy-build-system
9230 This variable is exported by @code{(guix build-system renpy)}. It implements
9231 the more or less standard build procedure used by Ren'py games, which consists
9232 of loading @code{#:game} once, thereby creating bytecode for it.
9234 It further creates a wrapper script in @code{bin/} and a desktop entry in
9235 @code{share/applications}, both of which can be used to launch the game.
9237 Which Ren'py package is used can be specified with @code{#:renpy}.
9238 Games can also be installed in outputs other than ``out'' by using
9242 @defvr {Scheme Variable} qt-build-system
9243 This variable is exported by @code{(guix build-system qt)}. It
9244 is intended for use with applications using Qt or KDE.
9246 This build system adds the following two phases to the ones defined by
9247 @code{cmake-build-system}:
9251 The phase @code{check-setup} prepares the environment for running
9252 the checks as commonly used by Qt test programs.
9253 For now this only sets some environment variables:
9254 @code{QT_QPA_PLATFORM=offscreen},
9255 @code{DBUS_FATAL_WARNINGS=0} and
9256 @code{CTEST_OUTPUT_ON_FAILURE=1}.
9258 This phase is added before the @code{check} phase.
9259 It's a separate phase to ease adjusting if necessary.
9262 The phase @code{qt-wrap}
9263 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
9264 and output. In case some path is found, all programs in the output's
9265 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
9266 are wrapped in scripts defining the necessary environment variables.
9268 It is possible to exclude specific package outputs from that wrapping process
9269 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
9270 This is useful when an output is known not to contain any Qt binaries, and
9271 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
9274 This phase is added after the @code{install} phase.
9278 @defvr {Scheme Variable} r-build-system
9279 This variable is exported by @code{(guix build-system r)}. It
9280 implements the build procedure used by @uref{https://r-project.org, R}
9281 packages, which essentially is little more than running @samp{R CMD
9282 INSTALL --library=/gnu/store/@dots{}} in an environment where
9283 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
9284 run after installation using the R function
9285 @code{tools::testInstalledPackage}.
9288 @defvr {Scheme Variable} rakudo-build-system
9289 This variable is exported by @code{(guix build-system rakudo)}. It
9290 implements the build procedure used by @uref{https://rakudo.org/,
9291 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
9292 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
9293 installs the binaries, library files and the resources, as well as wrap
9294 the files under the @code{bin/} directory. Tests can be skipped by
9295 passing @code{#f} to the @code{tests?} parameter.
9297 Which rakudo package is used can be specified with @code{rakudo}.
9298 Which perl6-tap-harness package used for the tests can be specified with
9299 @code{#:prove6} or removed by passing @code{#f} to the
9300 @code{with-prove6?} parameter.
9301 Which perl6-zef package used for tests and installing can be specified
9302 with @code{#:zef} or removed by passing @code{#f} to the
9303 @code{with-zef?} parameter.
9306 @defvr {Scheme Variable} rebar-build-system
9307 This variable is exported by @code{(guix build-system rebar)}. It
9308 implements a build procedure around @uref{https://rebar3.org,rebar3},
9309 a build system for programs written in the Erlang language.
9311 It adds both @code{rebar3} and the @code{erlang} to the set of inputs.
9312 Different packages can be specified with the @code{#:rebar} and
9313 @code{#:erlang} parameters, respectively.
9315 This build system is based on @code{gnu-build-system}, but with the
9316 following phases changed:
9321 This phase, after unpacking the source like the @code{gnu-build-system}
9322 does, checks for a file @code{contents.tar.gz} at the top-level of the
9323 source. If this file exists, it will be unpacked, too. This eases
9324 handling of package hosted at @uref{https://hex.pm/},
9325 the Erlang and Elixir package repository.
9329 There are no @code{bootstrap} and @code{configure} phase because erlang
9330 packages typically don’t need to be configured.
9333 This phase runs @code{rebar3 compile}
9334 with the flags listed in @code{#:rebar-flags}.
9337 Unless @code{#:tests? #f} is passed,
9338 this phase runs @code{rebar3 eunit},
9339 or some other target specified with @code{#:test-target},
9340 with the flags listed in @code{#:rebar-flags},
9343 This installs the files created in the @i{default} profile, or some
9344 other profile specified with @code{#:install-profile}.
9349 @defvr {Scheme Variable} texlive-build-system
9350 This variable is exported by @code{(guix build-system texlive)}. It is
9351 used to build TeX packages in batch mode with a specified engine. The
9352 build system sets the @env{TEXINPUTS} variable to find all TeX source
9353 files in the inputs.
9355 By default it runs @code{luatex} on all files ending on @code{ins}. A
9356 different engine and format can be specified with the
9357 @code{#:tex-format} argument. Different build targets can be specified
9358 with the @code{#:build-targets} argument, which expects a list of file
9359 names. The build system adds only @code{texlive-bin} and
9360 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
9361 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
9362 and @code{#:texlive-latex-base}, respectively.
9364 The @code{#:tex-directory} parameter tells the build system where to
9365 install the built files under the texmf tree.
9368 @defvr {Scheme Variable} ruby-build-system
9369 This variable is exported by @code{(guix build-system ruby)}. It
9370 implements the RubyGems build procedure used by Ruby packages, which
9371 involves running @code{gem build} followed by @code{gem install}.
9373 The @code{source} field of a package that uses this build system
9374 typically references a gem archive, since this is the format that Ruby
9375 developers use when releasing their software. The build system unpacks
9376 the gem archive, potentially patches the source, runs the test suite,
9377 repackages the gem, and installs it. Additionally, directories and
9378 tarballs may be referenced to allow building unreleased gems from Git or
9379 a traditional source release tarball.
9381 Which Ruby package is used can be specified with the @code{#:ruby}
9382 parameter. A list of additional flags to be passed to the @command{gem}
9383 command can be specified with the @code{#:gem-flags} parameter.
9386 @defvr {Scheme Variable} waf-build-system
9387 This variable is exported by @code{(guix build-system waf)}. It
9388 implements a build procedure around the @code{waf} script. The common
9389 phases---@code{configure}, @code{build}, and @code{install}---are
9390 implemented by passing their names as arguments to the @code{waf}
9393 The @code{waf} script is executed by the Python interpreter. Which
9394 Python package is used to run the script can be specified with the
9395 @code{#:python} parameter.
9398 @defvr {Scheme Variable} scons-build-system
9399 This variable is exported by @code{(guix build-system scons)}. It
9400 implements the build procedure used by the SCons software construction
9401 tool. This build system runs @code{scons} to build the package,
9402 @code{scons test} to run tests, and then @code{scons install} to install
9405 Additional flags to be passed to @code{scons} can be specified with the
9406 @code{#:scons-flags} parameter. The default build and install targets
9407 can be overridden with @code{#:build-targets} and
9408 @code{#:install-targets} respectively. The version of Python used to
9409 run SCons can be specified by selecting the appropriate SCons package
9410 with the @code{#:scons} parameter.
9413 @defvr {Scheme Variable} haskell-build-system
9414 This variable is exported by @code{(guix build-system haskell)}. It
9415 implements the Cabal build procedure used by Haskell packages, which
9416 involves running @code{runhaskell Setup.hs configure
9417 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
9418 Instead of installing the package by running @code{runhaskell Setup.hs
9419 install}, to avoid trying to register libraries in the read-only
9420 compiler store directory, the build system uses @code{runhaskell
9421 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
9422 addition, the build system generates the package documentation by
9423 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
9424 is passed. Optional Haddock parameters can be passed with the help of
9425 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
9426 not found, the build system looks for @code{Setup.lhs} instead.
9428 Which Haskell compiler is used can be specified with the @code{#:haskell}
9429 parameter which defaults to @code{ghc}.
9432 @defvr {Scheme Variable} dub-build-system
9433 This variable is exported by @code{(guix build-system dub)}. It
9434 implements the Dub build procedure used by D packages, which
9435 involves running @code{dub build} and @code{dub run}.
9436 Installation is done by copying the files manually.
9438 Which D compiler is used can be specified with the @code{#:ldc}
9439 parameter which defaults to @code{ldc}.
9442 @anchor{emacs-build-system}
9443 @defvr {Scheme Variable} emacs-build-system
9444 This variable is exported by @code{(guix build-system emacs)}. It
9445 implements an installation procedure similar to the packaging system
9446 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9448 It first creates the @code{@code{package}-autoloads.el} file, then it
9449 byte compiles all Emacs Lisp files. Differently from the Emacs
9450 packaging system, the Info documentation files are moved to the standard
9451 documentation directory and the @file{dir} file is deleted. The Elisp
9452 package files are installed directly under @file{share/emacs/site-lisp}.
9455 @defvr {Scheme Variable} font-build-system
9456 This variable is exported by @code{(guix build-system font)}. It
9457 implements an installation procedure for font packages where upstream
9458 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
9459 need to be copied into place. It copies font files to standard
9460 locations in the output directory.
9463 @defvr {Scheme Variable} meson-build-system
9464 This variable is exported by @code{(guix build-system meson)}. It
9465 implements the build procedure for packages that use
9466 @url{https://mesonbuild.com, Meson} as their build system.
9468 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
9469 of inputs, and they can be changed with the parameters @code{#:meson}
9470 and @code{#:ninja} if needed.
9472 This build system is an extension of @code{gnu-build-system}, but with the
9473 following phases changed to some specific for Meson:
9478 The phase runs @code{meson} with the flags specified in
9479 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
9480 @code{debugoptimized} unless something else is specified in
9481 @code{#:build-type}.
9484 The phase runs @code{ninja} to build the package in parallel by default, but
9485 this can be changed with @code{#:parallel-build?}.
9488 The phase runs @samp{meson test} with a base set of options that cannot
9489 be overridden. This base set of options can be extended via the
9490 @code{#:test-options} argument, for example to select or skip a specific
9494 The phase runs @code{ninja install} and can not be changed.
9497 Apart from that, the build system also adds the following phases:
9502 This phase ensures that all binaries can find the libraries they need.
9503 It searches for required libraries in subdirectories of the package
9504 being built, and adds those to @code{RUNPATH} where needed. It also
9505 removes references to libraries left over from the build phase by
9506 @code{meson}, such as test dependencies, that aren't actually required
9507 for the program to run.
9509 @item glib-or-gtk-wrap
9510 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
9511 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
9513 @item glib-or-gtk-compile-schemas
9514 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
9515 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
9519 @defvr {Scheme Variable} linux-module-build-system
9520 @code{linux-module-build-system} allows building Linux kernel modules.
9522 @cindex build phases
9523 This build system is an extension of @code{gnu-build-system}, but with the
9524 following phases changed:
9529 This phase configures the environment so that the Linux kernel's Makefile
9530 can be used to build the external kernel module.
9533 This phase uses the Linux kernel's Makefile in order to build the external
9537 This phase uses the Linux kernel's Makefile in order to install the external
9541 It is possible and useful to specify the Linux kernel to use for building
9542 the module (in the @code{arguments} form of a package using the
9543 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
9546 @defvr {Scheme Variable} node-build-system
9547 This variable is exported by @code{(guix build-system node)}. It
9548 implements the build procedure used by @uref{https://nodejs.org,
9549 Node.js}, which implements an approximation of the @code{npm install}
9550 command, followed by an @code{npm test} command.
9552 Which Node.js package is used to interpret the @code{npm} commands can
9553 be specified with the @code{#:node} parameter which defaults to
9557 Lastly, for packages that do not need anything as sophisticated, a
9558 ``trivial'' build system is provided. It is trivial in the sense that
9559 it provides basically no support: it does not pull any implicit inputs,
9560 and does not have a notion of build phases.
9562 @defvr {Scheme Variable} trivial-build-system
9563 This variable is exported by @code{(guix build-system trivial)}.
9565 This build system requires a @code{#:builder} argument. This argument
9566 must be a Scheme expression that builds the package output(s)---as
9567 with @code{build-expression->derivation} (@pxref{Derivations,
9568 @code{build-expression->derivation}}).
9571 @defvr {Scheme Variable} channel-build-system
9572 This variable is exported by @code{(guix build-system channel)}.
9574 This build system is meant primarily for internal use. A package using
9575 this build system must have a channel specification as its @code{source}
9576 field (@pxref{Channels}); alternatively, its source can be a directory
9577 name, in which case an additional @code{#:commit} argument must be
9578 supplied to specify the commit being built (a hexadecimal string).
9580 The resulting package is a Guix instance of the given channel, similar
9581 to how @command{guix time-machine} would build it.
9585 @section Build Phases
9587 @cindex build phases, for packages
9588 Almost all package build systems implement a notion @dfn{build phases}:
9589 a sequence of actions that the build system executes, when you build the
9590 package, leading to the installed byproducts in the store. A notable
9591 exception is the ``bare-bones'' @code{trivial-build-system}
9592 (@pxref{Build Systems}).
9594 As discussed in the previous section, those build systems provide a
9595 standard list of phases. For @code{gnu-build-system}, the main build
9596 phases are the following:
9600 Define search path environment variables for all the input packages,
9601 including @env{PATH} (@pxref{Search Paths}).
9604 Unpack the source tarball, and change the current directory to the
9605 extracted source tree. If the source is actually a directory, copy it
9606 to the build tree, and enter that directory.
9608 @item patch-source-shebangs
9609 Patch shebangs encountered in source files so they refer to the right
9610 store file names. For instance, this changes @code{#!/bin/sh} to
9611 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
9614 Run the @file{configure} script with a number of default options, such
9615 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
9616 by the @code{#:configure-flags} argument.
9619 Run @code{make} with the list of flags specified with
9620 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
9621 (the default), build with @code{make -j}.
9624 Run @code{make check}, or some other target specified with
9625 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
9626 @code{#:parallel-tests?} argument is true (the default), run @code{make
9630 Run @code{make install} with the flags listed in @code{#:make-flags}.
9632 @item patch-shebangs
9633 Patch shebangs on the installed executable files.
9636 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
9637 is false), copying them to the @code{debug} output when available
9638 (@pxref{Installing Debugging Files}).
9640 @cindex RUNPATH, validation
9641 @anchor{phase-validate-runpath}
9642 @item validate-runpath
9643 Validate the @code{RUNPATH} of ELF binaries, unless
9644 @code{#:validate-runpath?} is false (@pxref{Build Systems}).
9646 This validation step consists in making sure that all the shared
9647 libraries needed by an ELF binary, which are listed as @code{DT_NEEDED}
9648 entries in its @code{PT_DYNAMIC} segment, appear in the
9649 @code{DT_RUNPATH} entry of that binary. In other words, it ensures that
9650 running or using those binaries will not result in a ``file not found''
9651 error at run time. @xref{Options, @option{-rpath},, ld, The GNU
9652 Linker}, for more information on @code{RUNPATH}.
9656 Other build systems have similar phases, with some variations. For
9657 example, @code{cmake-build-system} has same-named phases but its
9658 @code{configure} phases runs @code{cmake} instead of @code{./configure}.
9659 Others, such as @code{python-build-system}, have a wholly different list
9660 of standard phases. All this code runs on the @dfn{build side}: it is
9661 evaluated when you actually build the package, in a dedicated build
9662 process spawned by the build daemon (@pxref{Invoking guix-daemon}).
9664 Build phases are represented as association lists or ``alists''
9665 (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
9666 each key is a symbol for the name of the phase and the associated value
9667 is a procedure that accepts an arbitrary number of arguments. By
9668 convention, those procedures receive information about the build in the
9669 form of @dfn{keyword parameters}, which they can use or ignore.
9671 @vindex %standard-phases
9672 For example, here is how @code{(guix build gnu-build-system)} defines
9673 @code{%standard-phases}, the variable holding its alist of build
9674 phases@footnote{We present a simplified view of those build phases, but
9675 do take a look at @code{(guix build gnu-build-system)} to see all the
9679 ;; The build phases of 'gnu-build-system'.
9681 (define* (unpack #:key source #:allow-other-keys)
9682 ;; Extract the source tarball.
9683 (invoke "tar" "xvf" source))
9685 (define* (configure #:key outputs #:allow-other-keys)
9686 ;; Run the 'configure' script. Install to output "out".
9687 (let ((out (assoc-ref outputs "out")))
9688 (invoke "./configure"
9689 (string-append "--prefix=" out))))
9691 (define* (build #:allow-other-keys)
9695 (define* (check #:key (test-target "check") (tests? #true)
9697 ;; Run the test suite.
9699 (invoke "make" test-target)
9700 (display "test suite not run\n")))
9702 (define* (install #:allow-other-keys)
9703 ;; Install files to the prefix 'configure' specified.
9704 (invoke "make" "install"))
9706 (define %standard-phases
9707 ;; The list of standard phases (quite a few are omitted
9708 ;; for brevity). Each element is a symbol/procedure pair.
9709 (list (cons 'unpack unpack)
9710 (cons 'configure configure)
9713 (cons 'install install)))
9716 This shows how @code{%standard-phases} is defined as a list of
9717 symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
9718 Manual}). The first pair associates the @code{unpack} procedure with
9719 the @code{unpack} symbol---a name; the second pair defines the
9720 @code{configure} phase similarly, and so on. When building a package
9721 that uses @code{gnu-build-system} with its default list of phases, those
9722 phases are executed sequentially. You can see the name of each phase
9723 started and completed in the build log of packages that you build.
9725 Let's now look at the procedures themselves. Each one is defined with
9726 @code{define*}: @code{#:key} lists keyword parameters the procedure
9727 accepts, possibly with a default value, and @code{#:allow-other-keys}
9728 specifies that other keyword parameters are ignored (@pxref{Optional
9729 Arguments,,, guile, GNU Guile Reference Manual}).
9731 The @code{unpack} procedure honors the @code{source} parameter, which
9732 the build system uses to pass the file name of the source tarball (or
9733 version control checkout), and it ignores other parameters. The
9734 @code{configure} phase only cares about the @code{outputs} parameter, an
9735 alist mapping package output names to their store file name
9736 (@pxref{Packages with Multiple Outputs}). It extracts the file name of
9737 for @code{out}, the default output, and passes it to
9738 @command{./configure} as the installation prefix, meaning that
9739 @command{make install} will eventually copy all the files in that
9740 directory (@pxref{Configuration, configuration and makefile
9741 conventions,, standards, GNU Coding Standards}). @code{build} and
9742 @code{install} ignore all their arguments. @code{check} honors the
9743 @code{test-target} argument, which specifies the name of the Makefile
9744 target to run tests; it prints a message and skips tests when
9745 @code{tests?} is false.
9747 @cindex build phases, customizing
9748 The list of phases used for a particular package can be changed with the
9749 @code{#:phases} parameter of the build system. Changing the set of
9750 build phases boils down to building a new alist of phases based on the
9751 @code{%standard-phases} alist described above. This can be done with
9752 standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
9753 Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
9754 more convenient to do so with @code{modify-phases} (@pxref{Build
9755 Utilities, @code{modify-phases}}).
9757 Here is an example of a package definition that removes the
9758 @code{configure} phase of @code{%standard-phases} and inserts a new
9759 phase before the @code{build} phase, called
9760 @code{set-prefix-in-makefile}:
9763 (define-public example
9766 ;; other fields omitted
9767 (build-system gnu-build-system)
9769 '(#:phases (modify-phases %standard-phases
9771 (add-before 'build 'set-prefix-in-makefile
9772 (lambda* (#:key outputs #:allow-other-keys)
9773 ;; Modify the makefile so that its
9774 ;; 'PREFIX' variable points to "out".
9775 (let ((out (assoc-ref outputs "out")))
9776 (substitute* "Makefile"
9778 (string-append "PREFIX = "
9782 The new phase that is inserted is written as an anonymous procedure,
9783 introduced with @code{lambda*}; it honors the @code{outputs} parameter
9784 we have seen before. @xref{Build Utilities}, for more about the helpers
9785 used by this phase, and for more examples of @code{modify-phases}.
9787 @cindex code staging
9788 @cindex staging, of code
9789 Keep in mind that build phases are code evaluated at the time the
9790 package is actually built. This explains why the whole
9791 @code{modify-phases} expression above is quoted (it comes after the
9792 @code{'} or apostrophe): it is @dfn{staged} for later execution.
9793 @xref{G-Expressions}, for an explanation of code staging and the
9794 @dfn{code strata} involved.
9796 @node Build Utilities
9797 @section Build Utilities
9799 As soon as you start writing non-trivial package definitions
9800 (@pxref{Defining Packages}) or other build actions
9801 (@pxref{G-Expressions}), you will likely start looking for helpers for
9802 ``shell-like'' actions---creating directories, copying and deleting
9803 files recursively, manipulating build phases, and so on. The
9804 @code{(guix build utils)} module provides such utility procedures.
9806 Most build systems load @code{(guix build utils)} (@pxref{Build
9807 Systems}). Thus, when writing custom build phases for your package
9808 definitions, you can usually assume those procedures are in scope.
9810 When writing G-expressions, you can import @code{(guix build utils)} on
9811 the ``build side'' using @code{with-imported-modules} and then put it in
9812 scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
9813 guile, GNU Guile Reference Manual}):
9816 (with-imported-modules '((guix build utils)) ;import it
9817 (computed-file "empty-tree"
9820 (use-modules (guix build utils))
9822 ;; Happily use its 'mkdir-p' procedure.
9823 (mkdir-p (string-append #$output "/a/b/c")))))
9826 The remainder of this section is the reference for most of the utility
9827 procedures provided by @code{(guix build utils)}.
9829 @c TODO Document what's missing.
9831 @subsection Dealing with Store File Names
9833 This section documents procedures that deal with store file names.
9835 @deffn {Scheme Procedure} %store-directory
9836 Return the directory name of the store.
9839 @deffn {Scheme Procedure} store-file-name? @var{file}
9840 Return true if @var{file} is in the store.
9843 @deffn {Scheme Procedure} strip-store-file-name @var{file}
9844 Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
9845 The result is typically a @code{"@var{package}-@var{version}"} string.
9848 @deffn {Scheme Procedure} package-name->name+version @var{name}
9849 Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
9850 values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
9851 unavailable, @var{name} and @code{#f} are returned. The first hyphen
9852 followed by a digit is considered to introduce the version part.
9855 @subsection File Types
9857 The procedures below deal with files and file types.
9859 @deffn {Scheme Procedure} directory-exists? @var{dir}
9860 Return @code{#t} if @var{dir} exists and is a directory.
9863 @deffn {Scheme Procedure} executable-file? @var{file}
9864 Return @code{#t} if @var{file} exists and is executable.
9867 @deffn {Scheme Procedure} symbolic-link? @var{file}
9868 Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
9871 @deffn {Scheme Procedure} elf-file? @var{file}
9872 @deffnx {Scheme Procedure} ar-file? @var{file}
9873 @deffnx {Scheme Procedure} gzip-file? @var{file}
9874 Return @code{#t} if @var{file} is, respectively, an ELF file, an
9875 @code{ar} archive (such as a @file{.a} static library), or a gzip file.
9878 @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
9879 If @var{file} is a gzip file, reset its embedded timestamp (as with
9880 @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
9881 When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
9884 @subsection File Manipulation
9886 The following procedures and macros help create, modify, and delete
9887 files. They provide functionality comparable to common shell utilities
9888 such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
9889 @command{sed}. They complement Guile's extensive, but low-level, file
9890 system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
9892 @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
9893 Run @var{body} with @var{directory} as the process's current directory.
9895 Essentially, this macro changes the current directory to @var{directory}
9896 before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
9897 guile, GNU Guile Reference Manual}). It changes back to the initial
9898 directory when the dynamic extent of @var{body} is left, be it @i{via}
9899 normal procedure return or @i{via} a non-local exit such as an
9903 @deffn {Scheme Procedure} mkdir-p @var{dir}
9904 Create directory @var{dir} and all its ancestors.
9907 @deffn {Scheme Procedure} install-file @var{file} @var{directory}
9908 Create @var{directory} if it does not exist and copy @var{file} in there
9909 under the same name.
9912 @deffn {Scheme Procedure} make-file-writable @var{file}
9913 Make @var{file} writable for its owner.
9916 @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
9917 [#:log (current-output-port)] [#:follow-symlinks? #f] @
9918 [#:copy-file copy-file] [#:keep-mtime? #f] [#:keep-permissions? #t]
9919 Copy @var{source} directory to @var{destination}. Follow symlinks if
9920 @var{follow-symlinks?} is true; otherwise, just preserve them. Call
9921 @var{copy-file} to copy regular files. When @var{keep-mtime?} is true,
9922 keep the modification time of the files in @var{source} on those of
9923 @var{destination}. When @var{keep-permissions?} is true, preserve file
9924 permissions. Write verbose output to the @var{log} port.
9927 @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
9928 [#:follow-mounts? #f]
9929 Delete @var{dir} recursively, like @command{rm -rf}, without following
9930 symlinks. Don't follow mount points either, unless @var{follow-mounts?}
9931 is true. Report but ignore errors.
9934 @deffn {Scheme Syntax} substitute* @var{file} @
9935 ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
9936 Substitute @var{regexp} in @var{file} by the string returned by
9937 @var{body}. @var{body} is evaluated with each @var{match-var} bound to
9938 the corresponding positional regexp sub-expression. For example:
9944 (("foo([a-z]+)bar(.*)$" all letters end)
9945 (string-append "baz" letters end)))
9948 Here, anytime a line of @var{file} contains @code{hello}, it is replaced
9949 by @code{good morning}. Anytime a line of @var{file} matches the second
9950 regexp, @code{all} is bound to the complete match, @code{letters} is bound
9951 to the first sub-expression, and @code{end} is bound to the last one.
9953 When one of the @var{match-var} is @code{_}, no variable is bound to the
9954 corresponding match substring.
9956 Alternatively, @var{file} may be a list of file names, in which case
9957 they are all subject to the substitutions.
9959 Be careful about using @code{$} to match the end of a line; by itself it
9960 won't match the terminating newline of a line.
9963 @subsection File Search
9965 @cindex file, searching
9966 This section documents procedures to search and filter files.
9968 @deffn {Scheme Procedure} file-name-predicate @var{regexp}
9969 Return a predicate that returns true when passed a file name whose base
9970 name matches @var{regexp}.
9973 @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
9974 [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
9975 Return the lexicographically sorted list of files under @var{dir} for
9976 which @var{pred} returns true. @var{pred} is passed two arguments: the
9977 absolute file name, and its stat buffer; the default predicate always
9978 returns true. @var{pred} can also be a regular expression, in which
9979 case it is equivalent to @code{(file-name-predicate @var{pred})}.
9980 @var{stat} is used to obtain file information; using @code{lstat} means
9981 that symlinks are not followed. If @var{directories?} is true, then
9982 directories will also be included. If @var{fail-on-error?} is true,
9983 raise an exception upon error.
9986 Here are a few examples where we assume that the current directory is
9987 the root of the Guix source tree:
9990 ;; List all the regular files in the current directory.
9992 @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
9994 ;; List all the .scm files under gnu/services.
9995 (find-files "gnu/services" "\\.scm$")
9996 @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
9998 ;; List ar files in the current directory.
9999 (find-files "." (lambda (file stat) (ar-file? file)))
10000 @result{} ("./libformat.a" "./libstore.a" @dots{})
10003 @deffn {Scheme Procedure} which @var{program}
10004 Return the complete file name for @var{program} as found in
10005 @code{$PATH}, or @code{#f} if @var{program} could not be found.
10008 @deffn {Scheme Procedure} search-input-file @var{inputs} @var{name}
10009 @deffnx {Scheme Procedure} search-input-directory @var{inputs} @var{name}
10010 Return the complete file name for @var{name} as found in @var{inputs};
10011 @code{search-input-file} searches for a regular file and
10012 @code{search-input-directory} searches for a directory. If @var{name}
10013 could not be found, an exception is raised.
10015 Here, @var{inputs} must be an association list like @code{inputs} and
10016 @code{native-inputs} as available to build phases (@pxref{Build
10020 Here is a (simplified) example of how @code{search-input-file} is used
10021 in a build phase of the @code{wireguard-tools} package:
10024 (add-after 'install 'wrap-wg-quick
10025 (lambda* (#:key inputs outputs #:allow-other-keys)
10026 (let ((coreutils (string-append (assoc-ref inputs "coreutils")
10028 (wrap-program (search-input-file outputs "bin/wg-quick")
10029 #:sh (search-input-file inputs "bin/bash")
10030 `("PATH" ":" prefix ,(list coreutils))))))
10033 @subsection Program Invocation
10035 @cindex program invocation, from Scheme
10036 @cindex invoking programs, from Scheme
10037 You'll find handy procedures to spawn processes in this module,
10038 essentially convenient wrappers around Guile's @code{system*}
10039 (@pxref{Processes, @code{system*},, guile, GNU Guile Reference Manual}).
10041 @deffn {Scheme Procedure} invoke @var{program} @var{args}@dots{}
10042 Invoke @var{program} with the given @var{args}. Raise an
10043 @code{&invoke-error} exception if the exit code is non-zero; otherwise
10046 The advantage compared to @code{system*} is that you do not need to
10047 check the return value. This reduces boilerplate in shell-script-like
10048 snippets for instance in package build phases.
10051 @deffn {Scheme Procedure} invoke-error? @var{c}
10052 Return true if @var{c} is an @code{&invoke-error} condition.
10055 @deffn {Scheme Procedure} invoke-error-program @var{c}
10056 @deffnx {Scheme Procedure} invoke-error-arguments @var{c}
10057 @deffnx {Scheme Procedure} invoke-error-exit-status @var{c}
10058 @deffnx {Scheme Procedure} invoke-error-term-signal @var{c}
10059 @deffnx {Scheme Procedure} invoke-error-stop-signal @var{c}
10060 Access specific fields of @var{c}, an @code{&invoke-error} condition.
10063 @deffn {Scheme Procedure} report-invoke-error @var{c} [@var{port}]
10064 Report to @var{port} (by default the current error port) about @var{c},
10065 an @code{&invoke-error} condition, in a human-friendly way.
10067 Typical usage would look like this:
10070 (use-modules (srfi srfi-34) ;for 'guard'
10071 (guix build utils))
10073 (guard (c ((invoke-error? c)
10074 (report-invoke-error c)))
10075 (invoke "date" "--imaginary-option"))
10077 @print{} command "date" "--imaginary-option" failed with status 1
10081 @deffn {Scheme Procedure} invoke/quiet @var{program} @var{args}@dots{}
10082 Invoke @var{program} with @var{args} and capture @var{program}'s
10083 standard output and standard error. If @var{program} succeeds, print
10084 nothing and return the unspecified value; otherwise, raise a
10085 @code{&message} error condition that includes the status code and the
10086 output of @var{program}.
10091 (use-modules (srfi srfi-34) ;for 'guard'
10092 (srfi srfi-35) ;for 'message-condition?'
10093 (guix build utils))
10095 (guard (c ((message-condition? c)
10096 (display (condition-message c))))
10097 (invoke/quiet "date") ;all is fine
10098 (invoke/quiet "date" "--imaginary-option"))
10100 @print{} 'date --imaginary-option' exited with status 1; output follows:
10102 date: unrecognized option '--imaginary-option'
10103 Try 'date --help' for more information.
10107 @subsection Build Phases
10109 @cindex build phases
10110 The @code{(guix build utils)} also contains tools to manipulate build
10111 phases as used by build systems (@pxref{Build Systems}). Build phases
10112 are represented as association lists or ``alists'' (@pxref{Association
10113 Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
10114 naming the phase and the associated value is a procedure (@pxref{Build
10117 Guile core and the @code{(srfi srfi-1)} module both provide tools to
10118 manipulate alists. The @code{(guix build utils)} module complements
10119 those with tools written with build phases in mind.
10121 @cindex build phases, modifying
10122 @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
10123 Modify @var{phases} sequentially as per each @var{clause}, which may
10124 have one of the following forms:
10127 (delete @var{old-phase-name})
10128 (replace @var{old-phase-name} @var{new-phase})
10129 (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
10130 (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
10133 Where every @var{phase-name} above is an expression evaluating to a
10134 symbol, and @var{new-phase} an expression evaluating to a procedure.
10137 The example below is taken from the definition of the @code{grep}
10138 package. It adds a phase to run after the @code{install} phase, called
10139 @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
10140 is for anonymous procedures) that takes a @code{#:outputs} keyword
10141 argument and ignores extra keyword arguments (@pxref{Optional
10142 Arguments,,, guile, GNU Guile Reference Manual}, for more on
10143 @code{lambda*} and optional and keyword arguments.) The phase uses
10144 @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
10145 scripts so that they refer to @code{grep} by its absolute file name:
10148 (modify-phases %standard-phases
10149 (add-after 'install 'fix-egrep-and-fgrep
10150 ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
10151 ;; absolute file name instead of searching for it in $PATH.
10152 (lambda* (#:key outputs #:allow-other-keys)
10153 (let* ((out (assoc-ref outputs "out"))
10154 (bin (string-append out "/bin")))
10155 (substitute* (list (string-append bin "/egrep")
10156 (string-append bin "/fgrep"))
10158 (string-append "exec " bin "/grep")))))))
10161 In the example below, phases are modified in two ways: the standard
10162 @code{configure} phase is deleted, presumably because the package does
10163 not have a @file{configure} script or anything similar, and the default
10164 @code{install} phase is replaced by one that manually copies the
10165 executable files to be installed:
10168 (modify-phases %standard-phases
10169 (delete 'configure) ;no 'configure' script
10171 (lambda* (#:key outputs #:allow-other-keys)
10172 ;; The package's Makefile doesn't provide an "install"
10173 ;; rule so do it by ourselves.
10174 (let ((bin (string-append (assoc-ref outputs "out")
10176 (install-file "footswitch" bin)
10177 (install-file "scythe" bin)))))
10180 @c TODO: Add more examples.
10182 @subsection Wrappers
10184 @cindex program wrappers
10185 @cindex wrapping programs
10186 It is not unusual for a command to require certain environment variables
10187 to be set for proper functioning, typically search paths (@pxref{Search
10188 Paths}). Failing to do that, the command might fail to find files or
10189 other commands it relies on, or it might pick the ``wrong''
10190 ones---depending on the environment in which it runs. Examples include:
10194 a shell script that assumes all the commands it uses are in @env{PATH};
10197 a Guile program that assumes all its modules are in @env{GUILE_LOAD_PATH}
10198 and @env{GUILE_LOAD_COMPILED_PATH};
10201 a Qt application that expects to find certain plugins in
10202 @env{QT_PLUGIN_PATH}.
10205 For a package writer, the goal is to make sure commands always work the
10206 same rather than depend on some external settings. One way to achieve
10207 that is to @dfn{wrap} commands in a thin script that sets those
10208 environment variables, thereby ensuring that those run-time dependencies
10209 are always found. The wrapper would be used to set @env{PATH},
10210 @env{GUILE_LOAD_PATH}, or @env{QT_PLUGIN_PATH} in the examples above.
10212 To ease that task, the @code{(guix build utils)} module provides a
10213 couple of helpers to wrap commands.
10215 @deffn {Scheme Procedure} wrap-program @var{program} @
10216 [#:sh @var{sh}] [#:rest @var{variables}]
10217 Make a wrapper for @var{program}. @var{variables} should look like this:
10220 '(@var{variable} @var{delimiter} @var{position} @var{list-of-directories})
10223 where @var{delimiter} is optional. @code{:} will be used if
10224 @var{delimiter} is not given.
10226 For example, this call:
10229 (wrap-program "foo"
10230 '("PATH" ":" = ("/gnu/.../bar/bin"))
10231 '("CERT_PATH" suffix ("/gnu/.../baz/certs"
10235 will copy @file{foo} to @file{.foo-real} and create the file @file{foo}
10236 with the following contents:
10239 #!location/of/bin/bash
10240 export PATH="/gnu/.../bar/bin"
10241 export CERT_PATH="$CERT_PATH$@{CERT_PATH:+:@}/gnu/.../baz/certs:/qux/certs"
10242 exec -a $0 location/of/.foo-real "$@@"
10245 If @var{program} has previously been wrapped by @code{wrap-program}, the
10246 wrapper is extended with definitions for @var{variables}. If it is not,
10247 @var{sh} will be used as the interpreter.
10250 @deffn {Scheme Procedure} wrap-script @var{program} @
10251 [#:guile @var{guile}] [#:rest @var{variables}]
10252 Wrap the script @var{program} such that @var{variables} are set first.
10253 The format of @var{variables} is the same as in the @code{wrap-program}
10254 procedure. This procedure differs from @code{wrap-program} in that it
10255 does not create a separate shell script. Instead, @var{program} is
10256 modified directly by prepending a Guile script, which is interpreted as
10257 a comment in the script's language.
10259 Special encoding comments as supported by Python are recreated on the
10262 Note that this procedure can only be used once per file as Guile scripts are
10267 @section Search Paths
10269 @cindex search path
10270 Many programs and libraries look for input data in a @dfn{search path},
10271 a list of directories: shells like Bash look for executables in the
10272 command search path, a C compiler looks for @file{.h} files in its
10273 header search path, the Python interpreter looks for @file{.py}
10274 files in its search path, the spell checker has a search path for
10275 dictionaries, and so on.
10277 Search paths can usually be defined or overridden @i{via} environment
10278 variables (@pxref{Environment Variables,,, libc, The GNU C Library
10279 Reference Manual}). For example, the search paths mentioned above can
10280 be changed by defining the @env{PATH}, @env{C_INCLUDE_PATH},
10281 @env{PYTHONPATH} (or @env{GUIX_PYTHONPATH}), and @env{DICPATH}
10282 environment variables---you know, all these something-PATH variables
10283 that you need to get right or things ``won't be found''.
10285 You may have noticed from the command line that Guix ``knows'' which
10286 search path environment variables should be defined, and how. When you
10287 install packages in your default profile, the file
10288 @file{~/.guix-profile/etc/profile} is created, which you can ``source''
10289 from the shell to set those variables. Likewise, if you ask
10290 @command{guix shell} to create an environment containing Python and
10291 NumPy, a Python library, and if you pass it the @option{--search-paths}
10292 option, it will tell you about @env{PATH} and @env{GUIX_PYTHONPATH}
10293 (@pxref{Invoking guix shell}):
10296 $ guix shell python python-numpy --pure --search-paths
10297 export PATH="/gnu/store/@dots{}-profile/bin"
10298 export GUIX_PYTHONPATH="/gnu/store/@dots{}-profile/lib/python3.9/site-packages"
10301 When you omit @option{--search-paths}, it defines these environment
10302 variables right away, such that Python can readily find NumPy:
10305 $ guix shell python python-numpy -- python3
10306 Python 3.9.6 (default, Jan 1 1970, 00:00:01)
10307 [GCC 10.3.0] on linux
10308 Type "help", "copyright", "credits" or "license" for more information.
10310 >>> numpy.version.version
10314 For this to work, the definition of the @code{python} package
10315 @emph{declares} the search path it cares about and its associated
10316 environment variable, @env{GUIX_PYTHONPATH}. It looks like this:
10322 ;; some fields omitted...
10323 (native-search-paths
10324 (list (search-path-specification
10325 (variable "GUIX_PYTHONPATH")
10326 (files (list "lib/python/3.9/site-packages"))))))
10329 What this @code{native-search-paths} field says is that, when the
10330 @code{python} package is used, the @env{GUIX_PYTHONPATH} environment
10331 variable must be defined to include all the
10332 @file{lib/python/3.9/site-packages} sub-directories encountered in its
10333 environment. (The @code{native-} bit means that, if we are in a
10334 cross-compilation environment, only native inputs may be added to the
10335 search path; @pxref{package Reference, @code{search-paths}}.)
10336 In the NumPy example above, the profile where
10337 @code{python} appears contains exactly one such sub-directory, and
10338 @env{GUIX_PYTHONPATH} is set to that. When there are several
10339 @file{lib/python/3.9/site-packages}---this is the case in package build
10340 environments---they are all added to @env{GUIX_PYTHONPATH}, separated by
10344 Notice that @env{GUIX_PYTHONPATH} is specified as part of the definition
10345 of the @code{python} package, and @emph{not} as part of that of
10346 @code{python-numpy}. This is because this environment variable
10347 ``belongs'' to Python, not NumPy: Python actually reads the value of
10348 that variable and honors it.
10350 Corollary: if you create a profile that does not contain @code{python},
10351 @code{GUIX_PYTHONPATH} will @emph{not} be defined, even if it contains
10352 packages that provide @file{.py} files:
10355 $ guix shell python-numpy --search-paths --pure
10356 export PATH="/gnu/store/@dots{}-profile/bin"
10359 This makes a lot of sense if we look at this profile in isolation: no
10360 software in this profile would read @env{GUIX_PYTHONPATH}.
10363 Of course, there are many variations on that theme: some packages honor
10364 more than one search path, some use separators other than colon, some
10365 accumulate several directories in their search path, and so on. A more
10366 complex example is the search path of libxml2: the value of the
10367 @env{XML_CATALOG_FILES} environment variable is space-separated, it must
10368 contain a list of @file{catalog.xml} files (not directories), which are
10369 to be found in @file{xml} sub-directories---nothing less. The search
10370 path specification looks like this:
10375 ;; some fields omitted
10376 (native-search-paths
10377 (list (search-path-specification
10378 (variable "XML_CATALOG_FILES")
10381 (file-pattern "^catalog\\.xml$")
10382 (file-type 'regular)))))
10385 Worry not, search path specifications are usually not this tricky.
10387 The @code{(guix search-paths)} module defines the data type of search
10388 path specifications and a number of helper procedures. Below is the
10389 reference of search path specifications.
10391 @deftp {Data Type} search-path-specification
10392 The data type for search path specifications.
10395 @item @code{variable}
10396 The name of the environment variable for this search path (a string).
10399 The list of sub-directories (strings) that should be added to the search
10402 @item @code{separator} (default: @code{":"})
10403 The string used to separate search path components.
10405 As a special case, a @code{separator} value of @code{#f} specifies a
10406 ``single-component search path''---in other words, a search path that
10407 cannot contain more than one element. This is useful in some cases,
10408 such as the @code{SSL_CERT_DIR} variable (honored by OpenSSL, cURL, and
10409 a few other packages) or the @code{ASPELL_DICT_DIR} variable (honored by
10410 the GNU Aspell spell checker), both of which must point to a single
10413 @item @code{file-type} (default: @code{'directory})
10414 The type of file being matched---@code{'directory} or @code{'regular},
10415 though it can be any symbol returned by @code{stat:type} (@pxref{File
10416 System, @code{stat},, guile, GNU Guile Reference Manual}).
10418 In the libxml2 example above, we would match regular files; in the
10419 Python example, we would match directories.
10421 @item @code{file-pattern} (default: @code{#f})
10422 This must be either @code{#f} or a regular expression specifying
10423 files to be matched @emph{within} the sub-directories specified by the
10424 @code{files} field.
10426 Again, the libxml2 example shows a situation where this is needed.
10430 Some search paths are not tied by a single package but to many packages.
10431 To reduce duplications, some of them are pre-defined in @code{(guix
10434 @defvr {Scheme Variable} $SSL_CERT_DIR
10435 @defvrx {Scheme Variable} $SSL_CERT_FILE
10436 These two search paths indicate where X.509 certificates can be found
10437 (@pxref{X.509 Certificates}).
10440 These pre-defined search paths can be used as in the following example:
10445 ;; some fields omitted ...
10446 (native-search-paths (list $SSL_CERT_DIR $SSL_CERT_FILE)))
10449 How do you turn search path specifications on one hand and a bunch of
10450 directories on the other hand in a set of environment variable
10451 definitions? That's the job of @code{evaluate-search-paths}.
10453 @deffn {Scheme Procedure} evaluate-search-paths @var{search-paths} @
10454 @var{directories} [@var{getenv}]
10455 Evaluate @var{search-paths}, a list of search-path specifications, for
10456 @var{directories}, a list of directory names, and return a list of
10457 specification/value pairs. Use @var{getenv} to determine the current
10458 settings and report only settings not already effective.
10461 The @code{(guix profiles)} provides a higher-level helper procedure,
10462 @code{load-profile}, that sets the environment variables of a profile.
10468 @cindex store items
10469 @cindex store paths
10471 Conceptually, the @dfn{store} is the place where derivations that have
10472 been built successfully are stored---by default, @file{/gnu/store}.
10473 Sub-directories in the store are referred to as @dfn{store items} or
10474 sometimes @dfn{store paths}. The store has an associated database that
10475 contains information such as the store paths referred to by each store
10476 path, and the list of @emph{valid} store items---results of successful
10477 builds. This database resides in @file{@var{localstatedir}/guix/db},
10478 where @var{localstatedir} is the state directory specified @i{via}
10479 @option{--localstatedir} at configure time, usually @file{/var}.
10481 The store is @emph{always} accessed by the daemon on behalf of its clients
10482 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
10483 connect to the daemon over a Unix-domain socket, send requests to it,
10484 and read the result---these are remote procedure calls, or RPCs.
10487 Users must @emph{never} modify files under @file{/gnu/store} directly.
10488 This would lead to inconsistencies and break the immutability
10489 assumptions of Guix's functional model (@pxref{Introduction}).
10491 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
10492 how to check the integrity of the store and attempt recovery from
10493 accidental modifications.
10496 The @code{(guix store)} module provides procedures to connect to the
10497 daemon, and to perform RPCs. These are described below. By default,
10498 @code{open-connection}, and thus all the @command{guix} commands,
10499 connect to the local daemon or to the URI specified by the
10500 @env{GUIX_DAEMON_SOCKET} environment variable.
10502 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
10503 When set, the value of this variable should be a file name or a URI
10504 designating the daemon endpoint. When it is a file name, it denotes a
10505 Unix-domain socket to connect to. In addition to file names, the
10506 supported URI schemes are:
10511 These are for Unix-domain sockets.
10512 @code{file:///var/guix/daemon-socket/socket} is equivalent to
10513 @file{/var/guix/daemon-socket/socket}.
10516 @cindex daemon, remote access
10517 @cindex remote access to the daemon
10518 @cindex daemon, cluster setup
10519 @cindex clusters, daemon setup
10520 These URIs denote connections over TCP/IP, without encryption nor
10521 authentication of the remote host. The URI must specify the host name
10522 and optionally a port number (by default port 44146 is used):
10525 guix://master.guix.example.org:1234
10528 This setup is suitable on local networks, such as clusters, where only
10529 trusted nodes may connect to the build daemon at
10530 @code{master.guix.example.org}.
10532 The @option{--listen} option of @command{guix-daemon} can be used to
10533 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
10534 @option{--listen}}).
10537 @cindex SSH access to build daemons
10538 These URIs allow you to connect to a remote daemon over SSH@. This
10539 feature requires Guile-SSH (@pxref{Requirements}) and a working
10540 @command{guile} binary in @env{PATH} on the destination machine. It
10541 supports public key and GSSAPI authentication. A typical URL might look
10545 ssh://charlie@@guix.example.org:22
10548 As for @command{guix copy}, the usual OpenSSH client configuration files
10549 are honored (@pxref{Invoking guix copy}).
10552 Additional URI schemes may be supported in the future.
10554 @c XXX: Remove this note when the protocol incurs fewer round trips
10555 @c and when (guix derivations) no longer relies on file system access.
10557 The ability to connect to remote build daemons is considered
10558 experimental as of @value{VERSION}. Please get in touch with us to
10559 share any problems or suggestions you may have (@pxref{Contributing}).
10563 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
10564 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
10565 @var{reserve-space?} is true, instruct it to reserve a little bit of
10566 extra space on the file system so that the garbage collector can still
10567 operate should the disk become full. Return a server object.
10569 @var{file} defaults to @code{%default-socket-path}, which is the normal
10570 location given the options that were passed to @command{configure}.
10573 @deffn {Scheme Procedure} close-connection @var{server}
10574 Close the connection to @var{server}.
10577 @defvr {Scheme Variable} current-build-output-port
10578 This variable is bound to a SRFI-39 parameter, which refers to the port
10579 where build and error logs sent by the daemon should be written.
10582 Procedures that make RPCs all take a server object as their first
10585 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
10586 @cindex invalid store items
10587 Return @code{#t} when @var{path} designates a valid store item and
10588 @code{#f} otherwise (an invalid item may exist on disk but still be
10589 invalid, for instance because it is the result of an aborted or failed
10592 A @code{&store-protocol-error} condition is raised if @var{path} is not
10593 prefixed by the store directory (@file{/gnu/store}).
10596 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
10597 Add @var{text} under file @var{name} in the store, and return its store
10598 path. @var{references} is the list of store paths referred to by the
10599 resulting store path.
10602 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
10604 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
10605 file names, or derivation/output pairs, using the specified
10606 @var{mode}---@code{(build-mode normal)} by default.
10609 Note that the @code{(guix monads)} module provides a monad as well as
10610 monadic versions of the above procedures, with the goal of making it
10611 more convenient to work with code that accesses the store (@pxref{The
10615 @i{This section is currently incomplete.}
10618 @section Derivations
10620 @cindex derivations
10621 Low-level build actions and the environment in which they are performed
10622 are represented by @dfn{derivations}. A derivation contains the
10623 following pieces of information:
10627 The outputs of the derivation---derivations produce at least one file or
10628 directory in the store, but may produce more.
10631 @cindex build-time dependencies
10632 @cindex dependencies, build-time
10633 The inputs of the derivations---i.e., its build-time dependencies---which may
10634 be other derivations or plain files in the store (patches, build scripts,
10638 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
10641 The file name of a build script in the store, along with the arguments
10645 A list of environment variables to be defined.
10649 @cindex derivation path
10650 Derivations allow clients of the daemon to communicate build actions to
10651 the store. They exist in two forms: as an in-memory representation,
10652 both on the client- and daemon-side, and as files in the store whose
10653 name end in @file{.drv}---these files are referred to as @dfn{derivation
10654 paths}. Derivations paths can be passed to the @code{build-derivations}
10655 procedure to perform the build actions they prescribe (@pxref{The
10658 @cindex fixed-output derivations
10659 Operations such as file downloads and version-control checkouts for
10660 which the expected content hash is known in advance are modeled as
10661 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
10662 of a fixed-output derivation are independent of its inputs---e.g., a
10663 source code download produces the same result regardless of the download
10664 method and tools being used.
10667 @cindex run-time dependencies
10668 @cindex dependencies, run-time
10669 The outputs of derivations---i.e., the build results---have a set of
10670 @dfn{references}, as reported by the @code{references} RPC or the
10671 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
10672 are the set of run-time dependencies of the build results. References are a
10673 subset of the inputs of the derivation; this subset is automatically computed
10674 by the build daemon by scanning all the files in the outputs.
10676 The @code{(guix derivations)} module provides a representation of
10677 derivations as Scheme objects, along with procedures to create and
10678 otherwise manipulate derivations. The lowest-level primitive to create
10679 a derivation is the @code{derivation} procedure:
10681 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
10682 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
10683 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
10684 [#:system (%current-system)] [#:references-graphs #f] @
10685 [#:allowed-references #f] [#:disallowed-references #f] @
10686 [#:leaked-env-vars #f] [#:local-build? #f] @
10687 [#:substitutable? #t] [#:properties '()]
10688 Build a derivation with the given arguments, and return the resulting
10689 @code{<derivation>} object.
10691 When @var{hash} and @var{hash-algo} are given, a
10692 @dfn{fixed-output derivation} is created---i.e., one whose result is
10693 known in advance, such as a file download. If, in addition,
10694 @var{recursive?} is true, then that fixed output may be an executable
10695 file or a directory and @var{hash} must be the hash of an archive
10696 containing this output.
10698 When @var{references-graphs} is true, it must be a list of file
10699 name/store path pairs. In that case, the reference graph of each store
10700 path is exported in the build environment in the corresponding file, in
10701 a simple text format.
10703 When @var{allowed-references} is true, it must be a list of store items
10704 or outputs that the derivation's output may refer to. Likewise,
10705 @var{disallowed-references}, if true, must be a list of things the
10706 outputs may @emph{not} refer to.
10708 When @var{leaked-env-vars} is true, it must be a list of strings
10709 denoting environment variables that are allowed to ``leak'' from the
10710 daemon's environment to the build environment. This is only applicable
10711 to fixed-output derivations---i.e., when @var{hash} is true. The main
10712 use is to allow variables such as @code{http_proxy} to be passed to
10713 derivations that download files.
10715 When @var{local-build?} is true, declare that the derivation is not a
10716 good candidate for offloading and should rather be built locally
10717 (@pxref{Daemon Offload Setup}). This is the case for small derivations
10718 where the costs of data transfers would outweigh the benefits.
10720 When @var{substitutable?} is false, declare that substitutes of the
10721 derivation's output should not be used (@pxref{Substitutes}). This is
10722 useful, for instance, when building packages that capture details of the
10723 host CPU instruction set.
10725 @var{properties} must be an association list describing ``properties'' of the
10726 derivation. It is kept as-is, uninterpreted, in the derivation.
10730 Here's an example with a shell script as its builder, assuming
10731 @var{store} is an open connection to the daemon, and @var{bash} points
10732 to a Bash executable in the store:
10735 (use-modules (guix utils)
10737 (guix derivations))
10739 (let ((builder ; add the Bash script to the store
10740 (add-text-to-store store "my-builder.sh"
10741 "echo hello world > $out\n" '())))
10742 (derivation store "foo"
10743 bash `("-e" ,builder)
10744 #:inputs `((,bash) (,builder))
10745 #:env-vars '(("HOME" . "/homeless"))))
10746 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
10749 As can be guessed, this primitive is cumbersome to use directly. A
10750 better approach is to write build scripts in Scheme, of course! The
10751 best course of action for that is to write the build code as a
10752 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
10753 information, @pxref{G-Expressions}.
10755 Once upon a time, @code{gexp->derivation} did not exist and constructing
10756 derivations with build code written in Scheme was achieved with
10757 @code{build-expression->derivation}, documented below. This procedure
10758 is now deprecated in favor of the much nicer @code{gexp->derivation}.
10760 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
10761 @var{name} @var{exp} @
10762 [#:system (%current-system)] [#:inputs '()] @
10763 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
10764 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
10765 [#:references-graphs #f] [#:allowed-references #f] @
10766 [#:disallowed-references #f] @
10767 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
10768 Return a derivation that executes Scheme expression @var{exp} as a
10769 builder for derivation @var{name}. @var{inputs} must be a list of
10770 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
10771 @code{"out"} is assumed. @var{modules} is a list of names of Guile
10772 modules from the current search path to be copied in the store,
10773 compiled, and made available in the load path during the execution of
10774 @var{exp}---e.g., @code{((guix build utils) (guix build
10775 gnu-build-system))}.
10777 @var{exp} is evaluated in an environment where @code{%outputs} is bound
10778 to a list of output/path pairs, and where @code{%build-inputs} is bound
10779 to a list of string/output-path pairs made from @var{inputs}.
10780 Optionally, @var{env-vars} is a list of string pairs specifying the name
10781 and value of environment variables visible to the builder. The builder
10782 terminates by passing the result of @var{exp} to @code{exit}; thus, when
10783 @var{exp} returns @code{#f}, the build is considered to have failed.
10785 @var{exp} is built using @var{guile-for-build} (a derivation). When
10786 @var{guile-for-build} is omitted or is @code{#f}, the value of the
10787 @code{%guile-for-build} fluid is used instead.
10789 See the @code{derivation} procedure for the meaning of
10790 @var{references-graphs}, @var{allowed-references},
10791 @var{disallowed-references}, @var{local-build?}, and
10792 @var{substitutable?}.
10796 Here's an example of a single-output derivation that creates a directory
10797 containing one file:
10800 (let ((builder '(let ((out (assoc-ref %outputs "out")))
10801 (mkdir out) ; create /gnu/store/@dots{}-goo
10802 (call-with-output-file (string-append out "/test")
10804 (display '(hello guix) p))))))
10805 (build-expression->derivation store "goo" builder))
10807 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
10811 @node The Store Monad
10812 @section The Store Monad
10816 The procedures that operate on the store described in the previous
10817 sections all take an open connection to the build daemon as their first
10818 argument. Although the underlying model is functional, they either have
10819 side effects or depend on the current state of the store.
10821 The former is inconvenient: the connection to the build daemon has to be
10822 carried around in all those functions, making it impossible to compose
10823 functions that do not take that parameter with functions that do. The
10824 latter can be problematic: since store operations have side effects
10825 and/or depend on external state, they have to be properly sequenced.
10827 @cindex monadic values
10828 @cindex monadic functions
10829 This is where the @code{(guix monads)} module comes in. This module
10830 provides a framework for working with @dfn{monads}, and a particularly
10831 useful monad for our uses, the @dfn{store monad}. Monads are a
10832 construct that allows two things: associating ``context'' with values
10833 (in our case, the context is the store), and building sequences of
10834 computations (here computations include accesses to the store). Values
10835 in a monad---values that carry this additional context---are called
10836 @dfn{monadic values}; procedures that return such values are called
10837 @dfn{monadic procedures}.
10839 Consider this ``normal'' procedure:
10842 (define (sh-symlink store)
10843 ;; Return a derivation that symlinks the 'bash' executable.
10844 (let* ((drv (package-derivation store bash))
10845 (out (derivation->output-path drv))
10846 (sh (string-append out "/bin/bash")))
10847 (build-expression->derivation store "sh"
10848 `(symlink ,sh %output))))
10851 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
10852 as a monadic function:
10855 (define (sh-symlink)
10856 ;; Same, but return a monadic value.
10857 (mlet %store-monad ((drv (package->derivation bash)))
10858 (gexp->derivation "sh"
10859 #~(symlink (string-append #$drv "/bin/bash")
10863 There are several things to note in the second version: the @code{store}
10864 parameter is now implicit and is ``threaded'' in the calls to the
10865 @code{package->derivation} and @code{gexp->derivation} monadic
10866 procedures, and the monadic value returned by @code{package->derivation}
10867 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
10869 As it turns out, the call to @code{package->derivation} can even be
10870 omitted since it will take place implicitly, as we will see later
10871 (@pxref{G-Expressions}):
10874 (define (sh-symlink)
10875 (gexp->derivation "sh"
10876 #~(symlink (string-append #$bash "/bin/bash")
10881 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
10882 @c for the funny quote.
10883 Calling the monadic @code{sh-symlink} has no effect. As someone once
10884 said, ``you exit a monad like you exit a building on fire: by running''.
10885 So, to exit the monad and get the desired effect, one must use
10886 @code{run-with-store}:
10889 (run-with-store (open-connection) (sh-symlink))
10890 @result{} /gnu/store/...-sh-symlink
10893 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
10894 new ``commands'' to make it easier to deal with monadic procedures:
10895 @code{run-in-store}, and @code{enter-store-monad} (@pxref{Using Guix
10896 Interactively}). The former is used
10897 to ``run'' a single monadic value through the store:
10900 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
10901 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
10904 The latter enters a recursive REPL, where all the return values are
10905 automatically run through the store:
10908 scheme@@(guile-user)> ,enter-store-monad
10909 store-monad@@(guile-user) [1]> (package->derivation hello)
10910 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
10911 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
10912 $3 = "/gnu/store/@dots{}-foo"
10913 store-monad@@(guile-user) [1]> ,q
10914 scheme@@(guile-user)>
10918 Note that non-monadic values cannot be returned in the
10919 @code{store-monad} REPL.
10921 Other meta-commands are available at the REPL, such as @code{,build} to
10922 build a file-like object (@pxref{Using Guix Interactively}).
10924 The main syntactic forms to deal with monads in general are provided by
10925 the @code{(guix monads)} module and are described below.
10927 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
10928 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
10932 @deffn {Scheme Syntax} return @var{val}
10933 Return a monadic value that encapsulates @var{val}.
10936 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
10937 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
10938 procedures @var{mproc}@dots{}@footnote{This operation is commonly
10939 referred to as ``bind'', but that name denotes an unrelated procedure in
10940 Guile. Thus we use this somewhat cryptic symbol inherited from the
10941 Haskell language.}. There can be one @var{mproc} or several of them, as
10946 (with-monad %state-monad
10948 (lambda (x) (return (+ 1 x)))
10949 (lambda (x) (return (* 2 x)))))
10953 @result{} some-state
10957 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
10959 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
10961 Bind the variables @var{var} to the monadic values @var{mval} in
10962 @var{body}, which is a sequence of expressions. As with the bind
10963 operator, this can be thought of as ``unpacking'' the raw, non-monadic
10964 value ``contained'' in @var{mval} and making @var{var} refer to that
10965 raw, non-monadic value within the scope of the @var{body}. The form
10966 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
10967 @var{val}, as per @code{let}. The binding operations occur in sequence
10968 from left to right. The last expression of @var{body} must be a monadic
10969 expression, and its result will become the result of the @code{mlet} or
10970 @code{mlet*} when run in the @var{monad}.
10972 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
10973 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
10976 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
10977 Bind @var{mexp} and the following monadic expressions in sequence,
10978 returning the result of the last expression. Every expression in the
10979 sequence must be a monadic expression.
10981 This is akin to @code{mlet}, except that the return values of the
10982 monadic expressions are ignored. In that sense, it is analogous to
10983 @code{begin}, but applied to monadic expressions.
10986 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
10987 When @var{condition} is true, evaluate the sequence of monadic
10988 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
10989 @var{condition} is false, return @code{*unspecified*} in the current
10990 monad. Every expression in the sequence must be a monadic expression.
10993 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
10994 When @var{condition} is false, evaluate the sequence of monadic
10995 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
10996 @var{condition} is true, return @code{*unspecified*} in the current
10997 monad. Every expression in the sequence must be a monadic expression.
11000 @cindex state monad
11001 The @code{(guix monads)} module provides the @dfn{state monad}, which
11002 allows an additional value---the state---to be @emph{threaded} through
11003 monadic procedure calls.
11005 @defvr {Scheme Variable} %state-monad
11006 The state monad. Procedures in the state monad can access and change
11007 the state that is threaded.
11009 Consider the example below. The @code{square} procedure returns a value
11010 in the state monad. It returns the square of its argument, but also
11011 increments the current state value:
11015 (mlet %state-monad ((count (current-state)))
11016 (mbegin %state-monad
11017 (set-current-state (+ 1 count))
11018 (return (* x x)))))
11020 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
11025 When ``run'' through @code{%state-monad}, we obtain that additional state
11026 value, which is the number of @code{square} calls.
11029 @deffn {Monadic Procedure} current-state
11030 Return the current state as a monadic value.
11033 @deffn {Monadic Procedure} set-current-state @var{value}
11034 Set the current state to @var{value} and return the previous state as a
11038 @deffn {Monadic Procedure} state-push @var{value}
11039 Push @var{value} to the current state, which is assumed to be a list,
11040 and return the previous state as a monadic value.
11043 @deffn {Monadic Procedure} state-pop
11044 Pop a value from the current state and return it as a monadic value.
11045 The state is assumed to be a list.
11048 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
11049 Run monadic value @var{mval} starting with @var{state} as the initial
11050 state. Return two values: the resulting value, and the resulting state.
11053 The main interface to the store monad, provided by the @code{(guix
11054 store)} module, is as follows.
11056 @defvr {Scheme Variable} %store-monad
11057 The store monad---an alias for @code{%state-monad}.
11059 Values in the store monad encapsulate accesses to the store. When its
11060 effect is needed, a value of the store monad must be ``evaluated'' by
11061 passing it to the @code{run-with-store} procedure (see below).
11064 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
11065 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
11066 open store connection.
11069 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
11070 Return as a monadic value the absolute file name in the store of the file
11071 containing @var{text}, a string. @var{references} is a list of store items that the
11072 resulting text file refers to; it defaults to the empty list.
11075 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
11076 Return as a monadic value the absolute file name in the store of the file
11077 containing @var{data}, a bytevector. @var{references} is a list of store
11078 items that the resulting binary file refers to; it defaults to the empty list.
11081 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
11082 [#:recursive? #t] [#:select? (const #t)]
11083 Return the name of @var{file} once interned in the store. Use
11084 @var{name} as its store name, or the basename of @var{file} if
11085 @var{name} is omitted.
11087 When @var{recursive?} is true, the contents of @var{file} are added
11088 recursively; if @var{file} designates a flat file and @var{recursive?}
11089 is true, its contents are added, and its permission bits are kept.
11091 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
11092 @var{stat})} for each directory entry, where @var{file} is the entry's
11093 absolute file name and @var{stat} is the result of @code{lstat}; exclude
11094 entries for which @var{select?} does not return true.
11096 The example below adds a file to the store, under two different names:
11099 (run-with-store (open-connection)
11100 (mlet %store-monad ((a (interned-file "README"))
11101 (b (interned-file "README" "LEGU-MIN")))
11102 (return (list a b))))
11104 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
11109 The @code{(guix packages)} module exports the following package-related
11110 monadic procedures:
11112 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
11113 [#:system (%current-system)] [#:target #f] @
11115 Return as a monadic
11116 value in the absolute file name of @var{file} within the @var{output}
11117 directory of @var{package}. When @var{file} is omitted, return the name
11118 of the @var{output} directory of @var{package}. When @var{target} is
11119 true, use it as a cross-compilation target triplet.
11121 Note that this procedure does @emph{not} build @var{package}. Thus, the
11122 result might or might not designate an existing file. We recommend not
11123 using this procedure unless you know what you are doing.
11126 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
11127 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
11128 @var{target} [@var{system}]
11129 Monadic version of @code{package-derivation} and
11130 @code{package-cross-derivation} (@pxref{Defining Packages}).
11134 @node G-Expressions
11135 @section G-Expressions
11137 @cindex G-expression
11138 @cindex build code quoting
11139 So we have ``derivations'', which represent a sequence of build actions
11140 to be performed to produce an item in the store (@pxref{Derivations}).
11141 These build actions are performed when asking the daemon to actually
11142 build the derivations; they are run by the daemon in a container
11143 (@pxref{Invoking guix-daemon}).
11145 @cindex code staging
11146 @cindex staging, of code
11147 @cindex strata of code
11148 It should come as no surprise that we like to write these build actions
11149 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
11150 code@footnote{The term @dfn{stratum} in this context was coined by
11151 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
11152 Kiselyov, who has written insightful
11153 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
11154 on this topic}, refers to this kind of code generation as
11155 @dfn{staging}.}: the ``host code''---code that defines packages, talks
11156 to the daemon, etc.---and the ``build code''---code that actually
11157 performs build actions, such as making directories, invoking
11158 @command{make}, and so on (@pxref{Build Phases}).
11160 To describe a derivation and its build actions, one typically needs to
11161 embed build code inside host code. It boils down to manipulating build
11162 code as data, and the homoiconicity of Scheme---code has a direct
11163 representation as data---comes in handy for that. But we need more than
11164 the normal @code{quasiquote} mechanism in Scheme to construct build
11167 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
11168 S-expressions adapted to build expressions. G-expressions, or
11169 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
11170 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
11171 @code{#$}, and @code{#$@@}), which are comparable to
11172 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
11173 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
11174 GNU Guile Reference Manual}). However, there are major differences:
11178 Gexps are meant to be written to a file and run or manipulated by other
11182 When a high-level object such as a package or derivation is unquoted
11183 inside a gexp, the result is as if its output file name had been
11187 Gexps carry information about the packages or derivations they refer to,
11188 and these dependencies are automatically added as inputs to the build
11189 processes that use them.
11192 @cindex lowering, of high-level objects in gexps
11193 This mechanism is not limited to package and derivation
11194 objects: @dfn{compilers} able to ``lower'' other high-level objects to
11195 derivations or files in the store can be defined,
11196 such that these objects can also be inserted
11197 into gexps. For example, a useful type of high-level objects that can be
11198 inserted in a gexp is ``file-like objects'', which make it easy to
11199 add files to the store and to refer to them in
11200 derivations and such (see @code{local-file} and @code{plain-file}
11203 To illustrate the idea, here is an example of a gexp:
11210 (symlink (string-append #$coreutils "/bin/ls")
11214 This gexp can be passed to @code{gexp->derivation}; we obtain a
11215 derivation that builds a directory containing exactly one symlink to
11216 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
11219 (gexp->derivation "the-thing" build-exp)
11222 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
11223 substituted to the reference to the @var{coreutils} package in the
11224 actual build code, and @var{coreutils} is automatically made an input to
11225 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
11226 output)}) is replaced by a string containing the directory name of the
11227 output of the derivation.
11229 @cindex cross compilation
11230 In a cross-compilation context, it is useful to distinguish between
11231 references to the @emph{native} build of a package---that can run on the
11232 host---versus references to cross builds of a package. To that end, the
11233 @code{#+} plays the same role as @code{#$}, but is a reference to a
11234 native package build:
11237 (gexp->derivation "vi"
11240 (mkdir (string-append #$output "/bin"))
11241 (system* (string-append #+coreutils "/bin/ln")
11243 (string-append #$emacs "/bin/emacs")
11244 (string-append #$output "/bin/vi")))
11245 #:target "aarch64-linux-gnu")
11249 In the example above, the native build of @var{coreutils} is used, so
11250 that @command{ln} can actually run on the host; but then the
11251 cross-compiled build of @var{emacs} is referenced.
11253 @cindex imported modules, for gexps
11254 @findex with-imported-modules
11255 Another gexp feature is @dfn{imported modules}: sometimes you want to be
11256 able to use certain Guile modules from the ``host environment'' in the
11257 gexp, so those modules should be imported in the ``build environment''.
11258 The @code{with-imported-modules} form allows you to express that:
11261 (let ((build (with-imported-modules '((guix build utils))
11263 (use-modules (guix build utils))
11264 (mkdir-p (string-append #$output "/bin"))))))
11265 (gexp->derivation "empty-dir"
11268 (display "success!\n")
11273 In this example, the @code{(guix build utils)} module is automatically
11274 pulled into the isolated build environment of our gexp, such that
11275 @code{(use-modules (guix build utils))} works as expected.
11277 @cindex module closure
11278 @findex source-module-closure
11279 Usually you want the @emph{closure} of the module to be imported---i.e.,
11280 the module itself and all the modules it depends on---rather than just
11281 the module; failing to do that, attempts to use the module will fail
11282 because of missing dependent modules. The @code{source-module-closure}
11283 procedure computes the closure of a module by looking at its source file
11284 headers, which comes in handy in this case:
11287 (use-modules (guix modules)) ;for 'source-module-closure'
11289 (with-imported-modules (source-module-closure
11290 '((guix build utils)
11291 (gnu build image)))
11292 (gexp->derivation "something-with-vms"
11294 (use-modules (guix build utils)
11299 @cindex extensions, for gexps
11300 @findex with-extensions
11301 In the same vein, sometimes you want to import not just pure-Scheme
11302 modules, but also ``extensions'' such as Guile bindings to C libraries
11303 or other ``full-blown'' packages. Say you need the @code{guile-json}
11304 package available on the build side, here's how you would do it:
11307 (use-modules (gnu packages guile)) ;for 'guile-json'
11309 (with-extensions (list guile-json)
11310 (gexp->derivation "something-with-json"
11312 (use-modules (json))
11316 The syntactic form to construct gexps is summarized below.
11318 @deffn {Scheme Syntax} #~@var{exp}
11319 @deffnx {Scheme Syntax} (gexp @var{exp})
11320 Return a G-expression containing @var{exp}. @var{exp} may contain one
11321 or more of the following forms:
11325 @itemx (ungexp @var{obj})
11326 Introduce a reference to @var{obj}. @var{obj} may have one of the
11327 supported types, for example a package or a
11328 derivation, in which case the @code{ungexp} form is replaced by its
11329 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
11331 If @var{obj} is a list, it is traversed and references to supported
11332 objects are substituted similarly.
11334 If @var{obj} is another gexp, its contents are inserted and its
11335 dependencies are added to those of the containing gexp.
11337 If @var{obj} is another kind of object, it is inserted as is.
11339 @item #$@var{obj}:@var{output}
11340 @itemx (ungexp @var{obj} @var{output})
11341 This is like the form above, but referring explicitly to the
11342 @var{output} of @var{obj}---this is useful when @var{obj} produces
11343 multiple outputs (@pxref{Packages with Multiple Outputs}).
11346 @itemx #+@var{obj}:output
11347 @itemx (ungexp-native @var{obj})
11348 @itemx (ungexp-native @var{obj} @var{output})
11349 Same as @code{ungexp}, but produces a reference to the @emph{native}
11350 build of @var{obj} when used in a cross compilation context.
11352 @item #$output[:@var{output}]
11353 @itemx (ungexp output [@var{output}])
11354 Insert a reference to derivation output @var{output}, or to the main
11355 output when @var{output} is omitted.
11357 This only makes sense for gexps passed to @code{gexp->derivation}.
11359 @item #$@@@var{lst}
11360 @itemx (ungexp-splicing @var{lst})
11361 Like the above, but splices the contents of @var{lst} inside the
11364 @item #+@@@var{lst}
11365 @itemx (ungexp-native-splicing @var{lst})
11366 Like the above, but refers to native builds of the objects listed in
11371 G-expressions created by @code{gexp} or @code{#~} are run-time objects
11372 of the @code{gexp?} type (see below).
11375 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
11376 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
11377 in their execution environment.
11379 Each item in @var{modules} can be the name of a module, such as
11380 @code{(guix build utils)}, or it can be a module name, followed by an
11381 arrow, followed by a file-like object:
11384 `((guix build utils)
11386 ((guix config) => ,(scheme-file "config.scm"
11387 #~(define-module @dots{}))))
11391 In the example above, the first two modules are taken from the search
11392 path, and the last one is created from the given file-like object.
11394 This form has @emph{lexical} scope: it has an effect on the gexps
11395 directly defined in @var{body}@dots{}, but not on those defined, say, in
11396 procedures called from @var{body}@dots{}.
11399 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
11400 Mark the gexps defined in @var{body}@dots{} as requiring
11401 @var{extensions} in their build and execution environment.
11402 @var{extensions} is typically a list of package objects such as those
11403 defined in the @code{(gnu packages guile)} module.
11405 Concretely, the packages listed in @var{extensions} are added to the
11406 load path while compiling imported modules in @var{body}@dots{}; they
11407 are also added to the load path of the gexp returned by
11411 @deffn {Scheme Procedure} gexp? @var{obj}
11412 Return @code{#t} if @var{obj} is a G-expression.
11415 G-expressions are meant to be written to disk, either as code building
11416 some derivation, or as plain files in the store. The monadic procedures
11417 below allow you to do that (@pxref{The Store Monad}, for more
11418 information about monads).
11420 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
11421 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
11422 [#:hash #f] [#:hash-algo #f] @
11423 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
11424 [#:module-path @code{%load-path}] @
11425 [#:effective-version "2.2"] @
11426 [#:references-graphs #f] [#:allowed-references #f] @
11427 [#:disallowed-references #f] @
11428 [#:leaked-env-vars #f] @
11429 [#:script-name (string-append @var{name} "-builder")] @
11430 [#:deprecation-warnings #f] @
11431 [#:local-build? #f] [#:substitutable? #t] @
11432 [#:properties '()] [#:guile-for-build #f]
11433 Return a derivation @var{name} that runs @var{exp} (a gexp) with
11434 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
11435 stored in a file called @var{script-name}. When @var{target} is true,
11436 it is used as the cross-compilation target triplet for packages referred
11439 @var{modules} is deprecated in favor of @code{with-imported-modules}.
11441 make @var{modules} available in the evaluation context of @var{exp};
11442 @var{modules} is a list of names of Guile modules searched in
11443 @var{module-path} to be copied in the store, compiled, and made available in
11444 the load path during the execution of @var{exp}---e.g., @code{((guix
11445 build utils) (guix build gnu-build-system))}.
11447 @var{effective-version} determines the string to use when adding extensions of
11448 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
11450 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
11453 When @var{references-graphs} is true, it must be a list of tuples of one of the
11457 (@var{file-name} @var{package})
11458 (@var{file-name} @var{package} @var{output})
11459 (@var{file-name} @var{derivation})
11460 (@var{file-name} @var{derivation} @var{output})
11461 (@var{file-name} @var{store-item})
11464 The right-hand-side of each element of @var{references-graphs} is automatically made
11465 an input of the build process of @var{exp}. In the build environment, each
11466 @var{file-name} contains the reference graph of the corresponding item, in a simple
11469 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
11470 In the latter case, the list denotes store items that the result is allowed to
11471 refer to. Any reference to another store item will lead to a build error.
11472 Similarly for @var{disallowed-references}, which can list items that must not be
11473 referenced by the outputs.
11475 @var{deprecation-warnings} determines whether to show deprecation warnings while
11476 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
11478 The other arguments are as for @code{derivation} (@pxref{Derivations}).
11481 @cindex file-like objects
11482 The @code{local-file}, @code{plain-file}, @code{computed-file},
11483 @code{program-file}, and @code{scheme-file} procedures below return
11484 @dfn{file-like objects}. That is, when unquoted in a G-expression,
11485 these objects lead to a file in the store. Consider this G-expression:
11488 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
11489 #$(local-file "/tmp/my-nscd.conf"))
11492 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
11493 to the store. Once expanded, for instance @i{via}
11494 @code{gexp->derivation}, the G-expression refers to that copy under
11495 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
11496 does not have any effect on what the G-expression does.
11497 @code{plain-file} can be used similarly; it differs in that the file
11498 content is directly passed as a string.
11500 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
11501 [#:recursive? #f] [#:select? (const #t)]
11502 Return an object representing local file @var{file} to add to the store;
11503 this object can be used in a gexp. If @var{file} is a literal string
11504 denoting a relative file name, it is looked up relative to the source
11505 file where it appears; if @var{file} is not a literal string, it is
11506 looked up relative to the current working directory at run time.
11507 @var{file} will be added to the store under @var{name}--by default the
11508 base name of @var{file}.
11510 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
11511 designates a flat file and @var{recursive?} is true, its contents are added, and its
11512 permission bits are kept.
11514 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
11515 @var{stat})} for each directory entry, where @var{file} is the entry's
11516 absolute file name and @var{stat} is the result of @code{lstat}; exclude
11517 entries for which @var{select?} does not return true.
11519 This is the declarative counterpart of the @code{interned-file} monadic
11520 procedure (@pxref{The Store Monad, @code{interned-file}}).
11523 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
11524 Return an object representing a text file called @var{name} with the given
11525 @var{content} (a string or a bytevector) to be added to the store.
11527 This is the declarative counterpart of @code{text-file}.
11530 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
11531 [#:local-build? #t]
11533 Return an object representing the store item @var{name}, a file or
11534 directory computed by @var{gexp}. When @var{local-build?} is true (the
11535 default), the derivation is built locally. @var{options} is a list of
11536 additional arguments to pass to @code{gexp->derivation}.
11538 This is the declarative counterpart of @code{gexp->derivation}.
11541 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
11542 [#:guile (default-guile)] [#:module-path %load-path] @
11543 [#:system (%current-system)] [#:target #f]
11544 Return an executable script @var{name} that runs @var{exp} using
11545 @var{guile}, with @var{exp}'s imported modules in its search path.
11546 Look up @var{exp}'s modules in @var{module-path}.
11548 The example below builds a script that simply invokes the @command{ls}
11552 (use-modules (guix gexp) (gnu packages base))
11554 (gexp->script "list-files"
11555 #~(execl #$(file-append coreutils "/bin/ls")
11559 When ``running'' it through the store (@pxref{The Store Monad,
11560 @code{run-with-store}}), we obtain a derivation that produces an
11561 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
11564 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
11566 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
11570 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
11571 [#:guile #f] [#:module-path %load-path]
11572 Return an object representing the executable store item @var{name} that
11573 runs @var{gexp}. @var{guile} is the Guile package used to execute that
11574 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
11576 This is the declarative counterpart of @code{gexp->script}.
11579 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
11580 [#:set-load-path? #t] [#:module-path %load-path] @
11582 [#:guile (default-guile)]
11583 Return a derivation that builds a file @var{name} containing @var{exp}.
11584 When @var{splice?} is true, @var{exp} is considered to be a list of
11585 expressions that will be spliced in the resulting file.
11587 When @var{set-load-path?} is true, emit code in the resulting file to
11588 set @code{%load-path} and @code{%load-compiled-path} to honor
11589 @var{exp}'s imported modules. Look up @var{exp}'s modules in
11592 The resulting file holds references to all the dependencies of @var{exp}
11593 or a subset thereof.
11596 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
11597 [#:splice? #f] [#:set-load-path? #t]
11598 Return an object representing the Scheme file @var{name} that contains
11601 This is the declarative counterpart of @code{gexp->file}.
11604 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
11605 Return as a monadic value a derivation that builds a text file
11606 containing all of @var{text}. @var{text} may list, in addition to
11607 strings, objects of any type that can be used in a gexp: packages,
11608 derivations, local file objects, etc. The resulting store file holds
11609 references to all these.
11611 This variant should be preferred over @code{text-file} anytime the file
11612 to create will reference items from the store. This is typically the
11613 case when building a configuration file that embeds store file names,
11617 (define (profile.sh)
11618 ;; Return the name of a shell script in the store that
11619 ;; initializes the 'PATH' environment variable.
11620 (text-file* "profile.sh"
11621 "export PATH=" coreutils "/bin:"
11622 grep "/bin:" sed "/bin\n"))
11625 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
11626 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
11627 preventing them from being garbage-collected during its lifetime.
11630 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
11631 Return an object representing store file @var{name} containing
11632 @var{text}. @var{text} is a sequence of strings and file-like objects,
11636 (mixed-text-file "profile"
11637 "export PATH=" coreutils "/bin:" grep "/bin")
11640 This is the declarative counterpart of @code{text-file*}.
11643 @deffn {Scheme Procedure} file-union @var{name} @var{files}
11644 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
11645 Each item in @var{files} must be a two-element list where the first element is the
11646 file name to use in the new directory, and the second element is a gexp
11647 denoting the target file. Here's an example:
11651 `(("hosts" ,(plain-file "hosts"
11652 "127.0.0.1 localhost"))
11653 ("bashrc" ,(plain-file "bashrc"
11654 "alias ls='ls --color=auto'"))))
11657 This yields an @code{etc} directory containing these two files.
11660 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
11661 Return a directory that is the union of @var{things}, where @var{things} is a list of
11662 file-like objects denoting directories. For example:
11665 (directory-union "guile+emacs" (list guile emacs))
11668 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
11671 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
11672 Return a file-like object that expands to the concatenation of @var{obj}
11673 and @var{suffix}, where @var{obj} is a lowerable object and each
11674 @var{suffix} is a string.
11676 As an example, consider this gexp:
11679 (gexp->script "run-uname"
11680 #~(system* #$(file-append coreutils
11684 The same effect could be achieved with:
11687 (gexp->script "run-uname"
11688 #~(system* (string-append #$coreutils
11692 There is one difference though: in the @code{file-append} case, the
11693 resulting script contains the absolute file name as a string, whereas in
11694 the second case, the resulting script contains a @code{(string-append
11695 @dots{})} expression to construct the file name @emph{at run time}.
11698 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
11699 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
11700 Bind @var{system} to the currently targeted system---e.g.,
11701 @code{"x86_64-linux"}---within @var{body}.
11703 In the second case, additionally bind @var{target} to the current
11704 cross-compilation target---a GNU triplet such as
11705 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
11708 @code{let-system} is useful in the occasional case where the object
11709 spliced into the gexp depends on the target system, as in this example:
11713 #+(let-system system
11714 (cond ((string-prefix? "armhf-" system)
11715 (file-append qemu "/bin/qemu-system-arm"))
11716 ((string-prefix? "x86_64-" system)
11717 (file-append qemu "/bin/qemu-system-x86_64"))
11719 (error "dunno!"))))
11720 "-net" "user" #$image)
11724 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
11725 This macro is similar to the @code{parameterize} form for
11726 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
11727 Guile Reference Manual}). The key difference is that it takes effect
11728 when the file-like object returned by @var{exp} is lowered to a
11729 derivation or store item.
11731 A typical use of @code{with-parameters} is to force the system in effect
11732 for a given object:
11735 (with-parameters ((%current-system "i686-linux"))
11739 The example above returns an object that corresponds to the i686 build
11740 of Coreutils, regardless of the current value of @code{%current-system}.
11744 Of course, in addition to gexps embedded in ``host'' code, there are
11745 also modules containing build tools. To make it clear that they are
11746 meant to be used in the build stratum, these modules are kept in the
11747 @code{(guix build @dots{})} name space.
11749 @cindex lowering, of high-level objects in gexps
11750 Internally, high-level objects are @dfn{lowered}, using their compiler,
11751 to either derivations or store items. For instance, lowering a package
11752 yields a derivation, and lowering a @code{plain-file} yields a store
11753 item. This is achieved using the @code{lower-object} monadic procedure.
11755 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
11757 Return as a value in @code{%store-monad} the derivation or store item
11758 corresponding to @var{obj} for @var{system}, cross-compiling for
11759 @var{target} if @var{target} is true. @var{obj} must be an object that
11760 has an associated gexp compiler, such as a @code{<package>}.
11763 @deffn {Procedure} gexp->approximate-sexp @var{gexp}
11764 Sometimes, it may be useful to convert a G-exp into a S-exp. For
11765 example, some linters (@pxref{Invoking guix lint}) peek into the build
11766 phases of a package to detect potential problems. This conversion can
11767 be achieved with this procedure. However, some information can be lost
11768 in the process. More specifically, lowerable objects will be silently
11769 replaced with some arbitrary object -- currently the list
11770 @code{(*approximate*)}, but this may change.
11773 @node Invoking guix repl
11774 @section Invoking @command{guix repl}
11776 @cindex REPL, read-eval-print loop, script
11777 The @command{guix repl} command makes it easier to program Guix in Guile
11778 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
11779 programming (@pxref{Using Guile Interactively,,, guile,
11780 GNU Guile Reference Manual}), or by running Guile scripts
11781 (@pxref{Running Guile Scripts,,, guile,
11782 GNU Guile Reference Manual}).
11783 Compared to just launching the @command{guile}
11784 command, @command{guix repl} guarantees that all the Guix modules and all its
11785 dependencies are available in the search path.
11787 The general syntax is:
11790 guix repl @var{options} [@var{file} @var{args}]
11793 When a @var{file} argument is provided, @var{file} is
11794 executed as a Guile scripts:
11797 guix repl my-script.scm
11800 To pass arguments to the script, use @code{--} to prevent them from
11801 being interpreted as arguments to @command{guix repl} itself:
11804 guix repl -- my-script.scm --input=foo.txt
11807 To make a script executable directly from the shell, using the guix
11808 executable that is on the user's search path, add the following two
11809 lines at the top of the script:
11812 @code{#!/usr/bin/env -S guix repl --}
11816 Without a file name argument, a Guile REPL is started, allowing for
11817 interactive use (@pxref{Using Guix Interactively}):
11821 scheme@@(guile-user)> ,use (gnu packages base)
11822 scheme@@(guile-user)> coreutils
11823 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
11827 In addition, @command{guix repl} implements a simple machine-readable REPL
11828 protocol for use by @code{(guix inferior)}, a facility to interact with
11829 @dfn{inferiors}, separate processes running a potentially different revision
11832 The available options are as follows:
11835 @item --type=@var{type}
11836 @itemx -t @var{type}
11837 Start a REPL of the given @var{TYPE}, which can be one of the following:
11841 This is default, and it spawns a standard full-featured Guile REPL.
11843 Spawn a REPL that uses the machine-readable protocol. This is the protocol
11844 that the @code{(guix inferior)} module speaks.
11847 @item --listen=@var{endpoint}
11848 By default, @command{guix repl} reads from standard input and writes to
11849 standard output. When this option is passed, it will instead listen for
11850 connections on @var{endpoint}. Here are examples of valid options:
11853 @item --listen=tcp:37146
11854 Accept connections on localhost on port 37146.
11856 @item --listen=unix:/tmp/socket
11857 Accept connections on the Unix-domain socket @file{/tmp/socket}.
11860 @item --load-path=@var{directory}
11861 @itemx -L @var{directory}
11862 Add @var{directory} to the front of the package module search path
11863 (@pxref{Package Modules}).
11865 This allows users to define their own packages and make them visible to
11866 the script or REPL.
11869 Inhibit loading of the @file{~/.guile} file. By default, that
11870 configuration file is loaded when spawning a @code{guile} REPL.
11873 @node Using Guix Interactively
11874 @section Using Guix Interactively
11876 @cindex interactive use
11877 @cindex REPL, read-eval-print loop
11878 The @command{guix repl} command gives you access to a warm and friendly
11879 @dfn{read-eval-print loop} (REPL) (@pxref{Invoking guix repl}). If
11880 you're getting into Guix programming---defining your own packages,
11881 writing manifests, defining services for Guix System or Guix Home,
11882 etc.---you will surely find it convenient to toy with ideas at the REPL.
11884 If you use Emacs, the most convenient way to do that is with Geiser
11885 (@pxref{The Perfect Setup}), but you do not have to use Emacs to enjoy
11886 the REPL@. When using @command{guix repl} or @command{guile} in the
11887 terminal, we recommend using Readline for completion and Colorized to
11888 get colorful output. To do that, you can run:
11891 guix install guile guile-readline guile-colorized
11895 ... and then create a @file{.guile} file in your home directory containing
11899 (use-modules (ice-9 readline) (ice-9 colorized))
11901 (activate-readline)
11902 (activate-colorized)
11905 The REPL lets you evaluate Scheme code; you type a Scheme expression at
11906 the prompt, and the REPL prints what it evaluates to:
11910 scheme@@(guix-user)> (+ 2 3)
11912 scheme@@(guix-user)> (string-append "a" "b")
11916 It becomes interesting when you start fiddling with Guix at the REPL.
11917 The first thing you'll want to do is to ``import'' the @code{(guix)}
11918 module, which gives access to the main part of the programming
11919 interface, and perhaps a bunch of useful Guix modules. You could type
11920 @code{(use-modules (guix))}, which is valid Scheme code to import a
11921 module (@pxref{Using Guile Modules,,, guile, GNU Guile Reference
11922 Manual}), but the REPL provides the @code{use} @dfn{command} as a
11923 shorthand notation (@pxref{REPL Commands,,, guile, GNU Guile Reference
11927 scheme@@(guix-user)> ,use (guix)
11928 scheme@@(guix-user)> ,use (gnu packages base)
11931 Notice that REPL commands are introduced by a leading comma. A REPL
11932 command like @code{use} is not valid Scheme code; it's interpreted
11933 specially by the REPL.
11935 Guix extends the Guile REPL with additional commands for convenience.
11936 Among those, the @code{build} command comes in handy: it ensures that
11937 the given file-like object is built, building it if needed, and returns
11938 its output file name(s). In the example below, we build the
11939 @code{coreutils} and @code{grep} packages, as well as a ``computed
11940 file'' (@pxref{G-Expressions, @code{computed-file}}), and we use the
11941 @code{scandir} procedure to list the files in Grep's @code{/bin}
11945 scheme@@(guix-user)> ,build coreutils
11946 $1 = "/gnu/store/@dots{}-coreutils-8.32-debug"
11947 $2 = "/gnu/store/@dots{}-coreutils-8.32"
11948 scheme@@(guix-user)> ,build grep
11949 $3 = "/gnu/store/@dots{}-grep-3.6"
11950 scheme@@(guix-user)> ,build (computed-file "x" #~(mkdir #$output))
11951 building /gnu/store/@dots{}-x.drv...
11952 $4 = "/gnu/store/@dots{}-x"
11953 scheme@@(guix-user)> ,use(ice-9 ftw)
11954 scheme@@(guix-user)> (scandir (string-append $3 "/bin"))
11955 $5 = ("." ".." "egrep" "fgrep" "grep")
11958 At a lower-level, a useful command is @code{lower}: it takes a file-like
11959 object and ``lowers'' it into a derivation (@pxref{Derivations}) or a
11963 scheme@@(guix-user)> ,lower grep
11964 $6 = #<derivation /gnu/store/@dots{}-grep-3.6.drv => /gnu/store/@dots{}-grep-3.6 7f0e639115f0>
11965 scheme@@(guix-user)> ,lower (plain-file "x" "Hello!")
11966 $7 = "/gnu/store/@dots{}-x"
11969 The full list of REPL commands can be seen by typing @code{,help guix}
11970 and is given below for reference.
11972 @deffn {REPL command} build @var{object}
11973 Lower @var{object} and build it if it's not already built, returning its
11974 output file name(s).
11977 @deffn {REPL command} lower @var{object}
11978 Lower @var{object} into a derivation or store file name and return it.
11981 @deffn {REPL command} verbosity @var{level}
11982 Change build verbosity to @var{level}.
11984 This is similar to the @option{--verbosity} command-line option
11985 (@pxref{Common Build Options}): level 0 means total silence, level 1
11986 shows build events only, and higher levels print build logs.
11989 @deffn {REPL command} run-in-store @var{exp}
11990 Run @var{exp}, a monadic expresssion, through the store monad.
11991 @xref{The Store Monad}, for more information.
11994 @deffn {REPL command} enter-store-monad
11995 Enter a new REPL to evaluate monadic expressions (@pxref{The Store
11996 Monad}). You can quit this ``inner'' REPL by typing @code{,q}.
11999 @c *********************************************************************
12003 This section describes Guix command-line utilities. Some of them are
12004 primarily targeted at developers and users who write new package
12005 definitions, while others are more generally useful. They complement
12006 the Scheme programming interface of Guix in a convenient way.
12009 * Invoking guix build:: Building packages from the command line.
12010 * Invoking guix edit:: Editing package definitions.
12011 * Invoking guix download:: Downloading a file and printing its hash.
12012 * Invoking guix hash:: Computing the cryptographic hash of a file.
12013 * Invoking guix import:: Importing package definitions.
12014 * Invoking guix refresh:: Updating package definitions.
12015 * Invoking guix style:: Styling package definitions.
12016 * Invoking guix lint:: Finding errors in package definitions.
12017 * Invoking guix size:: Profiling disk usage.
12018 * Invoking guix graph:: Visualizing the graph of packages.
12019 * Invoking guix publish:: Sharing substitutes.
12020 * Invoking guix challenge:: Challenging substitute servers.
12021 * Invoking guix copy:: Copying to and from a remote store.
12022 * Invoking guix container:: Process isolation.
12023 * Invoking guix weather:: Assessing substitute availability.
12024 * Invoking guix processes:: Listing client processes.
12027 @node Invoking guix build
12028 @section Invoking @command{guix build}
12030 @cindex package building
12031 @cindex @command{guix build}
12032 The @command{guix build} command builds packages or derivations and
12033 their dependencies, and prints the resulting store paths. Note that it
12034 does not modify the user's profile---this is the job of the
12035 @command{guix package} command (@pxref{Invoking guix package}). Thus,
12036 it is mainly useful for distribution developers.
12038 The general syntax is:
12041 guix build @var{options} @var{package-or-derivation}@dots{}
12044 As an example, the following command builds the latest versions of Emacs
12045 and of Guile, displays their build logs, and finally displays the
12046 resulting directories:
12049 guix build emacs guile
12052 Similarly, the following command builds all the available packages:
12055 guix build --quiet --keep-going \
12056 $(guix package -A | awk '@{ print $1 "@@" $2 @}')
12059 @var{package-or-derivation} may be either the name of a package found in
12060 the software distribution such as @code{coreutils} or
12061 @code{coreutils@@8.20}, or a derivation such as
12062 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
12063 package with the corresponding name (and optionally version) is searched
12064 for among the GNU distribution modules (@pxref{Package Modules}).
12066 Alternatively, the @option{--expression} option may be used to specify a
12067 Scheme expression that evaluates to a package; this is useful when
12068 disambiguating among several same-named packages or package variants is
12071 There may be zero or more @var{options}. The available options are
12072 described in the subsections below.
12075 * Common Build Options:: Build options for most commands.
12076 * Package Transformation Options:: Creating variants of packages.
12077 * Additional Build Options:: Options specific to 'guix build'.
12078 * Debugging Build Failures:: Real life packaging experience.
12081 @node Common Build Options
12082 @subsection Common Build Options
12084 A number of options that control the build process are common to
12085 @command{guix build} and other commands that can spawn builds, such as
12086 @command{guix package} or @command{guix archive}. These are the
12091 @item --load-path=@var{directory}
12092 @itemx -L @var{directory}
12093 Add @var{directory} to the front of the package module search path
12094 (@pxref{Package Modules}).
12096 This allows users to define their own packages and make them visible to
12097 the command-line tools.
12099 @item --keep-failed
12101 Keep the build tree of failed builds. Thus, if a build fails, its build
12102 tree is kept under @file{/tmp}, in a directory whose name is shown at
12103 the end of the build log. This is useful when debugging build issues.
12104 @xref{Debugging Build Failures}, for tips and tricks on how to debug
12107 This option implies @option{--no-offload}, and it has no effect when
12108 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
12109 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
12113 Keep going when some of the derivations fail to build; return only once
12114 all the builds have either completed or failed.
12116 The default behavior is to stop as soon as one of the specified
12117 derivations has failed.
12121 Do not build the derivations.
12123 @anchor{fallback-option}
12125 When substituting a pre-built binary fails, fall back to building
12126 packages locally (@pxref{Substitution Failure}).
12128 @item --substitute-urls=@var{urls}
12129 @anchor{client-substitute-urls}
12130 Consider @var{urls} the whitespace-separated list of substitute source
12131 URLs, overriding the default list of URLs of @command{guix-daemon}
12132 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
12134 This means that substitutes may be downloaded from @var{urls}, provided
12135 they are signed by a key authorized by the system administrator
12136 (@pxref{Substitutes}).
12138 When @var{urls} is the empty string, substitutes are effectively
12141 @item --no-substitutes
12142 Do not use substitutes for build products. That is, always build things
12143 locally instead of allowing downloads of pre-built binaries
12144 (@pxref{Substitutes}).
12147 Do not ``graft'' packages. In practice, this means that package updates
12148 available as grafts are not applied. @xref{Security Updates}, for more
12149 information on grafts.
12151 @item --rounds=@var{n}
12152 Build each derivation @var{n} times in a row, and raise an error if
12153 consecutive build results are not bit-for-bit identical.
12155 This is a useful way to detect non-deterministic builds processes.
12156 Non-deterministic build processes are a problem because they make it
12157 practically impossible for users to @emph{verify} whether third-party
12158 binaries are genuine. @xref{Invoking guix challenge}, for more.
12160 When used in conjunction with @option{--keep-failed}, the differing
12161 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
12162 This makes it easy to look for differences between the two results.
12165 Do not use offload builds to other machines (@pxref{Daemon Offload
12166 Setup}). That is, always build things locally instead of offloading
12167 builds to remote machines.
12169 @item --max-silent-time=@var{seconds}
12170 When the build or substitution process remains silent for more than
12171 @var{seconds}, terminate it and report a build failure.
12173 By default, the daemon's setting is honored (@pxref{Invoking
12174 guix-daemon, @option{--max-silent-time}}).
12176 @item --timeout=@var{seconds}
12177 Likewise, when the build or substitution process lasts for more than
12178 @var{seconds}, terminate it and report a build failure.
12180 By default, the daemon's setting is honored (@pxref{Invoking
12181 guix-daemon, @option{--timeout}}).
12183 @c Note: This option is actually not part of %standard-build-options but
12184 @c most programs honor it.
12185 @cindex verbosity, of the command-line tools
12186 @cindex build logs, verbosity
12187 @item -v @var{level}
12188 @itemx --verbosity=@var{level}
12189 Use the given verbosity @var{level}, an integer. Choosing 0 means that
12190 no output is produced, 1 is for quiet output; 2 is similar to 1 but it
12191 additionally displays download URLs; 3 shows all the build log output on
12194 @item --cores=@var{n}
12196 Allow the use of up to @var{n} CPU cores for the build. The special
12197 value @code{0} means to use as many CPU cores as available.
12199 @item --max-jobs=@var{n}
12201 Allow at most @var{n} build jobs in parallel. @xref{Invoking
12202 guix-daemon, @option{--max-jobs}}, for details about this option and the
12203 equivalent @command{guix-daemon} option.
12205 @item --debug=@var{level}
12206 Produce debugging output coming from the build daemon. @var{level} must be an
12207 integer between 0 and 5; higher means more verbose output. Setting a level of
12208 4 or more may be helpful when debugging setup issues with the build daemon.
12212 Behind the scenes, @command{guix build} is essentially an interface to
12213 the @code{package-derivation} procedure of the @code{(guix packages)}
12214 module, and to the @code{build-derivations} procedure of the @code{(guix
12215 derivations)} module.
12217 In addition to options explicitly passed on the command line,
12218 @command{guix build} and other @command{guix} commands that support
12219 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
12221 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
12222 Users can define this variable to a list of command line options that
12223 will automatically be used by @command{guix build} and other
12224 @command{guix} commands that can perform builds, as in the example
12228 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
12231 These options are parsed independently, and the result is appended to
12232 the parsed command-line options.
12236 @node Package Transformation Options
12237 @subsection Package Transformation Options
12239 @cindex package variants
12240 Another set of command-line options supported by @command{guix build}
12241 and also @command{guix package} are @dfn{package transformation
12242 options}. These are options that make it possible to define @dfn{package
12243 variants}---for instance, packages built from different source code.
12244 This is a convenient way to create customized packages on the fly
12245 without having to type in the definitions of package variants
12246 (@pxref{Defining Packages}).
12248 Package transformation options are preserved across upgrades:
12249 @command{guix upgrade} attempts to apply transformation options
12250 initially used when creating the profile to the upgraded packages.
12252 The available options are listed below. Most commands support them and
12253 also support a @option{--help-transform} option that lists all the
12254 available options and a synopsis (these options are not shown in the
12255 @option{--help} output for brevity).
12259 @cindex performance, tuning code
12260 @cindex optimization, of package code
12261 @cindex tuning, of package code
12262 @cindex SIMD support
12263 @cindex tunable packages
12264 @cindex package multi-versioning
12265 @item --tune[=@var{cpu}]
12266 Use versions of the packages marked as ``tunable'' optimized for
12267 @var{cpu}. When @var{cpu} is @code{native}, or when it is omitted, tune
12268 for the CPU on which the @command{guix} command is running.
12270 Valid @var{cpu} names are those recognized by the underlying compiler,
12271 by default the GNU Compiler Collection. On x86_64 processors, this
12272 includes CPU names such as @code{nehalem}, @code{haswell}, and
12273 @code{skylake} (@pxref{x86 Options, @code{-march},, gcc, Using the GNU
12274 Compiler Collection (GCC)}).
12276 As new generations of CPUs come out, they augment the standard
12277 instruction set architecture (ISA) with additional instructions, in
12278 particular instructions for single-instruction/multiple-data (SIMD)
12279 parallel processing. For example, while Core2 and Skylake CPUs both
12280 implement the x86_64 ISA, only the latter supports AVX2 SIMD
12283 The primary gain one can expect from @option{--tune} is for programs
12284 that can make use of those SIMD capabilities @emph{and} that do not
12285 already have a mechanism to select the right optimized code at run time.
12286 Packages that have the @code{tunable?} property set are considered
12287 @dfn{tunable packages} by the @option{--tune} option; a package
12288 definition with the property set looks like this:
12292 (name "hello-simd")
12295 ;; This package may benefit from SIMD extensions so
12296 ;; mark it as "tunable".
12297 (properties '((tunable? . #t))))
12300 Other packages are not considered tunable. This allows Guix to use
12301 generic binaries in the cases where tuning for a specific CPU is
12302 unlikely to provide any gain.
12304 Tuned packages are built with @code{-march=@var{CPU}}; under the hood,
12305 the @option{-march} option is passed to the actual wrapper by a compiler
12306 wrapper. Since the build machine may not be able to run code for the
12307 target CPU micro-architecture, the test suite is not run when building a
12310 To reduce rebuilds to the minimum, tuned packages are @emph{grafted}
12311 onto packages that depend on them (@pxref{Security Updates, grafts}).
12312 Thus, using @option{--no-grafts} cancels the effect of @option{--tune}.
12314 We call this technique @dfn{package multi-versioning}: several variants
12315 of tunable packages may be built, one for each CPU variant. It is the
12316 coarse-grain counterpart of @dfn{function multi-versioning} as
12317 implemented by the GNU tool chain (@pxref{Function Multiversioning,,,
12318 gcc, Using the GNU Compiler Collection (GCC)}).
12320 @item --with-source=@var{source}
12321 @itemx --with-source=@var{package}=@var{source}
12322 @itemx --with-source=@var{package}@@@var{version}=@var{source}
12323 Use @var{source} as the source of @var{package}, and @var{version} as
12324 its version number.
12325 @var{source} must be a file name or a URL, as for @command{guix
12326 download} (@pxref{Invoking guix download}).
12328 When @var{package} is omitted,
12329 it is taken to be the package name specified on the
12330 command line that matches the base of @var{source}---e.g.,
12331 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
12332 package is @code{guile}.
12334 Likewise, when @var{version} is omitted, the version string is inferred from
12335 @var{source}; in the previous example, it is @code{2.0.10}.
12337 This option allows users to try out versions of packages other than the
12338 one provided by the distribution. The example below downloads
12339 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
12340 the @code{ed} package:
12343 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
12346 As a developer, @option{--with-source} makes it easy to test release
12350 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
12353 @dots{} or to build from a checkout in a pristine environment:
12356 $ git clone git://git.sv.gnu.org/guix.git
12357 $ guix build guix --with-source=guix@@1.0=./guix
12360 @item --with-input=@var{package}=@var{replacement}
12361 Replace dependency on @var{package} by a dependency on
12362 @var{replacement}. @var{package} must be a package name, and
12363 @var{replacement} must be a package specification such as @code{guile}
12364 or @code{guile@@1.8}.
12366 For instance, the following command builds Guix, but replaces its
12367 dependency on the current stable version of Guile with a dependency on
12368 the legacy version of Guile, @code{guile@@2.0}:
12371 guix build --with-input=guile=guile@@2.0 guix
12374 This is a recursive, deep replacement. So in this example, both
12375 @code{guix} and its dependency @code{guile-json} (which also depends on
12376 @code{guile}) get rebuilt against @code{guile@@2.0}.
12378 This is implemented using the @code{package-input-rewriting} Scheme
12379 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
12381 @item --with-graft=@var{package}=@var{replacement}
12382 This is similar to @option{--with-input} but with an important difference:
12383 instead of rebuilding the whole dependency chain, @var{replacement} is
12384 built and then @dfn{grafted} onto the binaries that were initially
12385 referring to @var{package}. @xref{Security Updates}, for more
12386 information on grafts.
12388 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
12389 and all its dependencies, replacing references to the version of GnuTLS
12390 they currently refer to:
12393 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
12396 This has the advantage of being much faster than rebuilding everything.
12397 But there is a caveat: it works if and only if @var{package} and
12398 @var{replacement} are strictly compatible---for example, if they provide
12399 a library, the application binary interface (ABI) of those libraries
12400 must be compatible. If @var{replacement} is somehow incompatible with
12401 @var{package}, then the resulting package may be unusable. Use with
12404 @cindex debugging info, rebuilding
12405 @item --with-debug-info=@var{package}
12406 Build @var{package} in a way that preserves its debugging info and graft
12407 it onto packages that depend on it. This is useful if @var{package}
12408 does not already provide debugging info as a @code{debug} output
12409 (@pxref{Installing Debugging Files}).
12411 For example, suppose you're experiencing a crash in Inkscape and would
12412 like to see what's up in GLib, a library deep down in Inkscape's
12413 dependency graph. GLib lacks a @code{debug} output, so debugging is
12414 tough. Fortunately, you rebuild GLib with debugging info and tack it on
12418 guix install inkscape --with-debug-info=glib
12421 Only GLib needs to be recompiled so this takes a reasonable amount of
12422 time. @xref{Installing Debugging Files}, for more info.
12425 Under the hood, this option works by passing the @samp{#:strip-binaries?
12426 #f} to the build system of the package of interest (@pxref{Build
12427 Systems}). Most build systems support that option but some do not. In
12428 that case, an error is raised.
12430 Likewise, if a C/C++ package is built without @code{-g} (which is rarely
12431 the case), debugging info will remain unavailable even when
12432 @code{#:strip-binaries?} is false.
12435 @cindex tool chain, changing the build tool chain of a package
12436 @item --with-c-toolchain=@var{package}=@var{toolchain}
12437 This option changes the compilation of @var{package} and everything that
12438 depends on it so that they get built with @var{toolchain} instead of the
12439 default GNU tool chain for C/C++.
12441 Consider this example:
12444 guix build octave-cli \
12445 --with-c-toolchain=fftw=gcc-toolchain@@10 \
12446 --with-c-toolchain=fftwf=gcc-toolchain@@10
12449 The command above builds a variant of the @code{fftw} and @code{fftwf}
12450 packages using version 10 of @code{gcc-toolchain} instead of the default
12451 tool chain, and then builds a variant of the GNU@tie{}Octave
12452 command-line interface using them. GNU@tie{}Octave itself is also built
12453 with @code{gcc-toolchain@@10}.
12455 This other example builds the Hardware Locality (@code{hwloc}) library
12456 and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
12460 guix build --with-c-toolchain=hwloc=clang-toolchain \
12461 intel-mpi-benchmarks
12465 There can be application binary interface (ABI) incompatibilities among
12466 tool chains. This is particularly true of the C++ standard library and
12467 run-time support libraries such as that of OpenMP@. By rebuilding all
12468 dependents with the same tool chain, @option{--with-c-toolchain} minimizes
12469 the risks of incompatibility but cannot entirely eliminate them. Choose
12470 @var{package} wisely.
12473 @item --with-git-url=@var{package}=@var{url}
12474 @cindex Git, using the latest commit
12475 @cindex latest commit, building
12476 Build @var{package} from the latest commit of the @code{master} branch of the
12477 Git repository at @var{url}. Git sub-modules of the repository are fetched,
12480 For example, the following command builds the NumPy Python library against the
12481 latest commit of the master branch of Python itself:
12484 guix build python-numpy \
12485 --with-git-url=python=https://github.com/python/cpython
12488 This option can also be combined with @option{--with-branch} or
12489 @option{--with-commit} (see below).
12491 @cindex continuous integration
12492 Obviously, since it uses the latest commit of the given branch, the result of
12493 such a command varies over time. Nevertheless it is a convenient way to
12494 rebuild entire software stacks against the latest commit of one or more
12495 packages. This is particularly useful in the context of continuous
12498 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
12499 consecutive accesses to the same repository. You may want to clean it up once
12500 in a while to save disk space.
12502 @item --with-branch=@var{package}=@var{branch}
12503 Build @var{package} from the latest commit of @var{branch}. If the
12504 @code{source} field of @var{package} is an origin with the @code{git-fetch}
12505 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
12506 repository URL is taken from that @code{source}. Otherwise you have to use
12507 @option{--with-git-url} to specify the URL of the Git repository.
12509 For instance, the following command builds @code{guile-sqlite3} from the
12510 latest commit of its @code{master} branch, and then builds @code{guix} (which
12511 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
12512 specific @code{guile-sqlite3} build:
12515 guix build --with-branch=guile-sqlite3=master cuirass
12518 @item --with-commit=@var{package}=@var{commit}
12519 This is similar to @option{--with-branch}, except that it builds from
12520 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
12521 Git commit SHA1 identifier, a tag, or a @command{git describe} style
12522 identifier such as @code{1.0-3-gabc123}.
12524 @item --with-patch=@var{package}=@var{file}
12525 Add @var{file} to the list of patches applied to @var{package}, where
12526 @var{package} is a spec such as @code{python@@3.8} or @code{glibc}.
12527 @var{file} must contain a patch; it is applied with the flags specified
12528 in the @code{origin} of @var{package} (@pxref{origin Reference}), which
12529 by default includes @code{-p1} (@pxref{patch Directories,,, diffutils,
12530 Comparing and Merging Files}).
12532 As an example, the command below rebuilds Coreutils with the GNU C
12533 Library (glibc) patched with the given patch:
12536 guix build coreutils --with-patch=glibc=./glibc-frob.patch
12539 In this example, glibc itself as well as everything that leads to
12540 Coreutils in the dependency graph is rebuilt.
12542 @cindex upstream, latest version
12543 @item --with-latest=@var{package}
12544 So you like living on the bleeding edge? This option is for you! It
12545 replaces occurrences of @var{package} in the dependency graph with its
12546 latest upstream version, as reported by @command{guix refresh}
12547 (@pxref{Invoking guix refresh}).
12549 It does so by determining the latest upstream release of @var{package}
12550 (if possible), downloading it, and authenticating it @emph{if} it comes
12551 with an OpenPGP signature.
12553 As an example, the command below builds Guix against the latest version
12557 guix build guix --with-latest=guile-json
12560 There are limitations. First, in cases where the tool cannot or does
12561 not know how to authenticate source code, you are at risk of running
12562 malicious code; a warning is emitted in this case. Second, this option
12563 simply changes the source used in the existing package definitions,
12564 which is not always sufficient: there might be additional dependencies
12565 that need to be added, patches to apply, and more generally the quality
12566 assurance work that Guix developers normally do will be missing.
12568 You've been warned! In all the other cases, it's a snappy way to stay
12569 on top. We encourage you to submit patches updating the actual package
12570 definitions once you have successfully tested an upgrade
12571 (@pxref{Contributing}).
12573 @cindex test suite, skipping
12574 @item --without-tests=@var{package}
12575 Build @var{package} without running its tests. This can be useful in
12576 situations where you want to skip the lengthy test suite of a
12577 intermediate package, or if a package's test suite fails in a
12578 non-deterministic fashion. It should be used with care because running
12579 the test suite is a good way to ensure a package is working as intended.
12581 Turning off tests leads to a different store item. Consequently, when
12582 using this option, anything that depends on @var{package} must be
12583 rebuilt, as in this example:
12586 guix install --without-tests=python python-notebook
12589 The command above installs @code{python-notebook} on top of
12590 @code{python} built without running its test suite. To do so, it also
12591 rebuilds everything that depends on @code{python}, including
12592 @code{python-notebook} itself.
12594 Internally, @option{--without-tests} relies on changing the
12595 @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
12596 Systems}). Note that some packages use a customized @code{check} phase
12597 that does not respect a @code{#:tests? #f} setting. Therefore,
12598 @option{--without-tests} has no effect on these packages.
12602 Wondering how to achieve the same effect using Scheme code, for example
12603 in your manifest, or how to write your own package transformation?
12604 @xref{Defining Package Variants}, for an overview of the programming
12605 interfaces available.
12607 @node Additional Build Options
12608 @subsection Additional Build Options
12610 The command-line options presented below are specific to @command{guix
12617 Build quietly, without displaying the build log; this is equivalent to
12618 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
12619 (or similar) and can always be retrieved using the @option{--log-file} option.
12621 @item --file=@var{file}
12622 @itemx -f @var{file}
12623 Build the package, derivation, or other file-like object that the code within
12624 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
12626 As an example, @var{file} might contain a package definition like this
12627 (@pxref{Defining Packages}):
12630 @include package-hello.scm
12633 The @var{file} may also contain a JSON representation of one or more
12634 package definitions. Running @code{guix build -f} on @file{hello.json}
12635 with the following contents would result in building the packages
12636 @code{myhello} and @code{greeter}:
12639 @verbatiminclude package-hello.json
12642 @item --manifest=@var{manifest}
12643 @itemx -m @var{manifest}
12644 Build all packages listed in the given @var{manifest}
12645 (@pxref{profile-manifest, @option{--manifest}}).
12647 @item --expression=@var{expr}
12648 @itemx -e @var{expr}
12649 Build the package or derivation @var{expr} evaluates to.
12651 For example, @var{expr} may be @code{(@@ (gnu packages guile)
12652 guile-1.8)}, which unambiguously designates this specific variant of
12653 version 1.8 of Guile.
12655 Alternatively, @var{expr} may be a G-expression, in which case it is used
12656 as a build program passed to @code{gexp->derivation}
12657 (@pxref{G-Expressions}).
12659 Lastly, @var{expr} may refer to a zero-argument monadic procedure
12660 (@pxref{The Store Monad}). The procedure must return a derivation as a
12661 monadic value, which is then passed through @code{run-with-store}.
12665 Build the source derivations of the packages, rather than the packages
12668 For instance, @code{guix build -S gcc} returns something like
12669 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
12672 The returned source tarball is the result of applying any patches and
12673 code snippets specified in the package @code{origin} (@pxref{Defining
12676 @cindex source, verification
12677 As with other derivations, the result of building a source derivation
12678 can be verified using the @option{--check} option (@pxref{build-check}).
12679 This is useful to validate that a (potentially already built or
12680 substituted, thus cached) package source matches against its declared
12683 Note that @command{guix build -S} compiles the sources only of the
12684 specified packages. They do not include the sources of statically
12685 linked dependencies and by themselves are insufficient for reproducing
12689 Fetch and return the source of @var{package-or-derivation} and all their
12690 dependencies, recursively. This is a handy way to obtain a local copy
12691 of all the source code needed to build @var{packages}, allowing you to
12692 eventually build them even without network access. It is an extension
12693 of the @option{--source} option and can accept one of the following
12694 optional argument values:
12698 This value causes the @option{--sources} option to behave in the same way
12699 as the @option{--source} option.
12702 Build the source derivations of all packages, including any source that
12703 might be listed as @code{inputs}. This is the default value.
12706 $ guix build --sources tzdata
12707 The following derivations will be built:
12708 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
12709 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
12713 Build the source derivations of all packages, as well of all transitive
12714 inputs to the packages. This can be used e.g.@: to
12715 prefetch package source for later offline building.
12718 $ guix build --sources=transitive tzdata
12719 The following derivations will be built:
12720 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
12721 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
12722 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
12723 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
12724 /gnu/store/@dots{}-make-4.1.tar.xz.drv
12725 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
12731 @item --system=@var{system}
12732 @itemx -s @var{system}
12733 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
12734 the system type of the build host. The @command{guix build} command allows
12735 you to repeat this option several times, in which case it builds for all the
12736 specified systems; other commands ignore extraneous @option{-s} options.
12739 The @option{--system} flag is for @emph{native} compilation and must not
12740 be confused with cross-compilation. See @option{--target} below for
12741 information on cross-compilation.
12744 An example use of this is on Linux-based systems, which can emulate
12745 different personalities. For instance, passing
12746 @option{--system=i686-linux} on an @code{x86_64-linux} system or
12747 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
12748 you to build packages in a complete 32-bit environment.
12751 Building for an @code{armhf-linux} system is unconditionally enabled on
12752 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
12753 allow for this functionality, notably the ThunderX.
12756 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
12757 is enabled (@pxref{Virtualization Services,
12758 @code{qemu-binfmt-service-type}}), you can build for any system for
12759 which a QEMU @code{binfmt_misc} handler is installed.
12761 Builds for a system other than that of the machine you are using can
12762 also be offloaded to a remote machine of the right architecture.
12763 @xref{Daemon Offload Setup}, for more information on offloading.
12765 @item --target=@var{triplet}
12766 @cindex cross-compilation
12767 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
12768 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
12769 configuration triplets,, autoconf, Autoconf}).
12771 @item --list-systems
12772 List all the supported systems, that can be passed as an argument to
12775 @item --list-targets
12776 List all the supported targets, that can be passed as an argument to
12779 @anchor{build-check}
12781 @cindex determinism, checking
12782 @cindex reproducibility, checking
12783 Rebuild @var{package-or-derivation}, which are already available in the
12784 store, and raise an error if the build results are not bit-for-bit
12787 This mechanism allows you to check whether previously installed
12788 substitutes are genuine (@pxref{Substitutes}), or whether the build result
12789 of a package is deterministic. @xref{Invoking guix challenge}, for more
12790 background information and tools.
12792 When used in conjunction with @option{--keep-failed}, the differing
12793 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
12794 This makes it easy to look for differences between the two results.
12797 @cindex repairing store items
12798 @cindex corruption, recovering from
12799 Attempt to repair the specified store items, if they are corrupt, by
12800 re-downloading or rebuilding them.
12802 This operation is not atomic and thus restricted to @code{root}.
12804 @item --derivations
12806 Return the derivation paths, not the output paths, of the given
12809 @item --root=@var{file}
12810 @itemx -r @var{file}
12811 @cindex GC roots, adding
12812 @cindex garbage collector roots, adding
12813 Make @var{file} a symlink to the result, and register it as a garbage
12816 Consequently, the results of this @command{guix build} invocation are
12817 protected from garbage collection until @var{file} is removed. When
12818 that option is omitted, build results are eligible for garbage
12819 collection as soon as the build completes. @xref{Invoking guix gc}, for
12823 @cindex build logs, access
12824 Return the build log file names or URLs for the given
12825 @var{package-or-derivation}, or raise an error if build logs are
12828 This works regardless of how packages or derivations are specified. For
12829 instance, the following invocations are equivalent:
12832 guix build --log-file $(guix build -d guile)
12833 guix build --log-file $(guix build guile)
12834 guix build --log-file guile
12835 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
12838 If a log is unavailable locally, and unless @option{--no-substitutes} is
12839 passed, the command looks for a corresponding log on one of the
12840 substitute servers (as specified with @option{--substitute-urls}).
12842 So for instance, imagine you want to see the build log of GDB on
12843 @code{aarch64}, but you are actually on an @code{x86_64} machine:
12846 $ guix build --log-file gdb -s aarch64-linux
12847 https://@value{SUBSTITUTE-SERVER-1}/log/@dots{}-gdb-7.10
12850 You can freely access a huge library of build logs!
12853 @node Debugging Build Failures
12854 @subsection Debugging Build Failures
12856 @cindex build failures, debugging
12857 When defining a new package (@pxref{Defining Packages}), you will
12858 probably find yourself spending some time debugging and tweaking the
12859 build until it succeeds. To do that, you need to operate the build
12860 commands yourself in an environment as close as possible to the one the
12863 To that end, the first thing to do is to use the @option{--keep-failed}
12864 or @option{-K} option of @command{guix build}, which will keep the
12865 failed build tree in @file{/tmp} or whatever directory you specified as
12866 @env{TMPDIR} (@pxref{Common Build Options, @option{--keep-failed}}).
12868 From there on, you can @command{cd} to the failed build tree and source
12869 the @file{environment-variables} file, which contains all the
12870 environment variable definitions that were in place when the build
12871 failed. So let's say you're debugging a build failure in package
12872 @code{foo}; a typical session would look like this:
12875 $ guix build foo -K
12876 @dots{} @i{build fails}
12877 $ cd /tmp/guix-build-foo.drv-0
12878 $ source ./environment-variables
12882 Now, you can invoke commands as if you were the daemon (almost) and
12883 troubleshoot your build process.
12885 Sometimes it happens that, for example, a package's tests pass when you
12886 run them manually but they fail when the daemon runs them. This can
12887 happen because the daemon runs builds in containers where, unlike in our
12888 environment above, network access is missing, @file{/bin/sh} does not
12889 exist, etc. (@pxref{Build Environment Setup}).
12891 In such cases, you may need to run inspect the build process from within
12892 a container similar to the one the build daemon creates:
12895 $ guix build -K foo
12897 $ cd /tmp/guix-build-foo.drv-0
12898 $ guix shell --no-grafts -C -D foo strace gdb
12899 [env]# source ./environment-variables
12903 Here, @command{guix shell -C} creates a container and spawns a new
12904 shell in it (@pxref{Invoking guix shell}). The @command{strace gdb}
12905 part adds the @command{strace} and @command{gdb} commands to
12906 the container, which you may find handy while debugging. The
12907 @option{--no-grafts} option makes sure we get the exact same
12908 environment, with ungrafted packages (@pxref{Security Updates}, for more
12911 To get closer to a container like that used by the build daemon, we can
12912 remove @file{/bin/sh}:
12918 (Don't worry, this is harmless: this is all happening in the throw-away
12919 container created by @command{guix shell}.)
12921 The @command{strace} command is probably not in the search path, but we
12925 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
12928 In this way, not only you will have reproduced the environment variables
12929 the daemon uses, you will also be running the build process in a container
12930 similar to the one the daemon uses.
12933 @node Invoking guix edit
12934 @section Invoking @command{guix edit}
12936 @cindex @command{guix edit}
12937 @cindex package definition, editing
12938 So many packages, so many source files! The @command{guix edit} command
12939 facilitates the life of users and packagers by pointing their editor at
12940 the source file containing the definition of the specified packages.
12944 guix edit gcc@@4.9 vim
12948 launches the program specified in the @env{VISUAL} or in the
12949 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
12952 If you are using a Guix Git checkout (@pxref{Building from Git}), or
12953 have created your own packages on @env{GUIX_PACKAGE_PATH}
12954 (@pxref{Package Modules}), you will be able to edit the package
12955 recipes. In other cases, you will be able to examine the read-only recipes
12956 for packages currently in the store.
12958 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
12959 @option{--load-path=@var{directory}} (or in short @option{-L
12960 @var{directory}}) allows you to add @var{directory} to the front of the
12961 package module search path and so make your own packages visible.
12963 @node Invoking guix download
12964 @section Invoking @command{guix download}
12966 @cindex @command{guix download}
12967 @cindex downloading package sources
12968 When writing a package definition, developers typically need to download
12969 a source tarball, compute its SHA256 hash, and write that
12970 hash in the package definition (@pxref{Defining Packages}). The
12971 @command{guix download} tool helps with this task: it downloads a file
12972 from the given URI, adds it to the store, and prints both its file name
12973 in the store and its SHA256 hash.
12975 The fact that the downloaded file is added to the store saves bandwidth:
12976 when the developer eventually tries to build the newly defined package
12977 with @command{guix build}, the source tarball will not have to be
12978 downloaded again because it is already in the store. It is also a
12979 convenient way to temporarily stash files, which may be deleted
12980 eventually (@pxref{Invoking guix gc}).
12982 The @command{guix download} command supports the same URIs as used in
12983 package definitions. In particular, it supports @code{mirror://} URIs.
12984 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
12985 Guile bindings for GnuTLS are available in the user's environment; when
12986 they are not available, an error is raised. @xref{Guile Preparations,
12987 how to install the GnuTLS bindings for Guile,, gnutls-guile,
12988 GnuTLS-Guile}, for more information.
12990 @command{guix download} verifies HTTPS server certificates by loading
12991 the certificates of X.509 authorities from the directory pointed to by
12992 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
12993 Certificates}), unless @option{--no-check-certificate} is used.
12995 The following options are available:
12998 @item --hash=@var{algorithm}
12999 @itemx -H @var{algorithm}
13000 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
13001 hash}, for more information.
13003 @item --format=@var{fmt}
13004 @itemx -f @var{fmt}
13005 Write the hash in the format specified by @var{fmt}. For more
13006 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
13008 @item --no-check-certificate
13009 Do not validate the X.509 certificates of HTTPS servers.
13011 When using this option, you have @emph{absolutely no guarantee} that you
13012 are communicating with the authentic server responsible for the given
13013 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
13015 @item --output=@var{file}
13016 @itemx -o @var{file}
13017 Save the downloaded file to @var{file} instead of adding it to the
13021 @node Invoking guix hash
13022 @section Invoking @command{guix hash}
13024 @cindex @command{guix hash}
13025 The @command{guix hash} command computes the hash of a file.
13026 It is primarily a convenience tool for anyone contributing to the
13027 distribution: it computes the cryptographic hash of one or more files, which can be
13028 used in the definition of a package (@pxref{Defining Packages}).
13030 The general syntax is:
13033 guix hash @var{option} @var{file} ...
13036 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
13037 hash of data read from standard input. @command{guix hash} has the
13042 @item --hash=@var{algorithm}
13043 @itemx -H @var{algorithm}
13044 Compute a hash using the specified @var{algorithm}, @code{sha256} by
13047 @var{algorithm} must be the name of a cryptographic hash algorithm
13048 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
13049 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
13050 Reference Manual}).
13052 @item --format=@var{fmt}
13053 @itemx -f @var{fmt}
13054 Write the hash in the format specified by @var{fmt}.
13056 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
13057 (@code{hex} and @code{hexadecimal} can be used as well).
13059 If the @option{--format} option is not specified, @command{guix hash}
13060 will output the hash in @code{nix-base32}. This representation is used
13061 in the definitions of packages.
13065 The @option{--recursive} option is deprecated in favor of
13066 @option{--serializer=nar} (see below); @option{-r} remains accepted as a
13067 convenient shorthand.
13069 @item --serializer=@var{type}
13070 @itemx -S @var{type}
13071 Compute the hash on @var{file} using @var{type} serialization.
13073 @var{type} may be one of the following:
13077 This is the default: it computes the hash of a file's contents.
13080 Compute the hash of a ``normalized archive'' (or ``nar'') containing
13081 @var{file}, including its children if it is a directory. Some of the
13082 metadata of @var{file} is part of the archive; for instance, when
13083 @var{file} is a regular file, the hash is different depending on whether
13084 @var{file} is executable or not. Metadata such as time stamps have no
13085 impact on the hash (@pxref{Invoking guix archive}, for more info on the
13087 @c FIXME: Replace xref above with xref to an ``Archive'' section when
13091 Compute the hash of the file or directory as a Git ``tree'', following
13092 the same method as the Git version control system.
13095 @item --exclude-vcs
13097 When combined with @option{--recursive}, exclude version control system
13098 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
13101 As an example, here is how you would compute the hash of a Git checkout,
13102 which is useful when using the @code{git-fetch} method (@pxref{origin
13106 $ git clone http://example.org/foo.git
13108 $ guix hash -x --serializer=nar .
13112 @node Invoking guix import
13113 @section Invoking @command{guix import}
13115 @cindex importing packages
13116 @cindex package import
13117 @cindex package conversion
13118 @cindex Invoking @command{guix import}
13119 The @command{guix import} command is useful for people who would like to
13120 add a package to the distribution with as little work as
13121 possible---a legitimate demand. The command knows of a few
13122 repositories from which it can ``import'' package metadata. The result
13123 is a package definition, or a template thereof, in the format we know
13124 (@pxref{Defining Packages}).
13126 The general syntax is:
13129 guix import @var{importer} @var{options}@dots{}
13132 @var{importer} specifies the source from which to import package
13133 metadata, and @var{options} specifies a package identifier and other
13134 options specific to @var{importer}.
13136 Some of the importers rely on the ability to run the @command{gpgv} command.
13137 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
13140 Currently, the available ``importers'' are:
13144 Import metadata for the given GNU package. This provides a template
13145 for the latest version of that GNU package, including the hash of its
13146 source tarball, and its canonical synopsis and description.
13148 Additional information such as the package dependencies and its
13149 license needs to be figured out manually.
13151 For example, the following command returns a package definition for
13155 guix import gnu hello
13158 Specific command-line options are:
13161 @item --key-download=@var{policy}
13162 As for @command{guix refresh}, specify the policy to handle missing
13163 OpenPGP keys when verifying the package signature. @xref{Invoking guix
13164 refresh, @option{--key-download}}.
13169 Import metadata from the @uref{https://pypi.python.org/, Python Package
13170 Index}. Information is taken from the JSON-formatted description
13171 available at @code{pypi.python.org} and usually includes all the relevant
13172 information, including package dependencies. For maximum efficiency, it
13173 is recommended to install the @command{unzip} utility, so that the
13174 importer can unzip Python wheels and gather data from them.
13176 The command below imports metadata for the latest version of the
13177 @code{itsdangerous} Python package:
13180 guix import pypi itsdangerous
13183 You can also ask for a specific version:
13186 guix import pypi itsdangerous@@1.1.0
13192 Traverse the dependency graph of the given upstream package recursively
13193 and generate package expressions for all those packages that are not yet
13199 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
13200 is taken from the JSON-formatted description available at
13201 @code{rubygems.org} and includes most relevant information, including
13202 runtime dependencies. There are some caveats, however. The metadata
13203 doesn't distinguish between synopses and descriptions, so the same string
13204 is used for both fields. Additionally, the details of non-Ruby
13205 dependencies required to build native extensions is unavailable and left
13206 as an exercise to the packager.
13208 The command below imports metadata for the @code{rails} Ruby package:
13211 guix import gem rails
13217 Traverse the dependency graph of the given upstream package recursively
13218 and generate package expressions for all those packages that are not yet
13225 Import metadata from @uref{https://content.minetest.net, ContentDB}.
13226 Information is taken from the JSON-formatted metadata provided through
13227 @uref{https://content.minetest.net/help/api/, ContentDB's API} and
13228 includes most relevant information, including dependencies. There are
13229 some caveats, however. The license information is often incomplete.
13230 The commit hash is sometimes missing. The descriptions are in the
13231 Markdown format, but Guix uses Texinfo instead. Texture packs and
13232 subgames are unsupported.
13234 The command below imports metadata for the Mesecons mod by Jeija:
13237 guix import minetest Jeija/mesecons
13240 The author name can also be left out:
13243 guix import minetest mesecons
13249 Traverse the dependency graph of the given upstream package recursively
13250 and generate package expressions for all those packages that are not yet
13256 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
13257 Information is taken from the JSON-formatted metadata provided through
13258 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
13259 relevant information, such as module dependencies. License information
13260 should be checked closely. If Perl is available in the store, then the
13261 @code{corelist} utility will be used to filter core modules out of the
13262 list of dependencies.
13264 The command command below imports metadata for the Acme::Boolean Perl
13268 guix import cpan Acme::Boolean
13273 @cindex Bioconductor
13274 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
13275 central repository for the @uref{https://r-project.org, GNU@tie{}R
13276 statistical and graphical environment}.
13278 Information is extracted from the @file{DESCRIPTION} file of the package.
13280 The command command below imports metadata for the Cairo R package:
13283 guix import cran Cairo
13286 You can also ask for a specific version:
13289 guix import cran rasterVis@@0.50.3
13292 When @option{--recursive} is added, the importer will traverse the
13293 dependency graph of the given upstream package recursively and generate
13294 package expressions for all those packages that are not yet in Guix.
13296 When @option{--style=specification} is added, the importer will generate
13297 package definitions whose inputs are package specifications instead of
13298 references to package variables. This is useful when generated package
13299 definitions are to be appended to existing user modules, as the list of
13300 used package modules need not be changed. The default is
13301 @option{--style=variable}.
13303 When @option{--archive=bioconductor} is added, metadata is imported from
13304 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
13305 packages for the analysis and comprehension of high-throughput
13306 genomic data in bioinformatics.
13308 Information is extracted from the @file{DESCRIPTION} file contained in the
13311 The command below imports metadata for the GenomicRanges R package:
13314 guix import cran --archive=bioconductor GenomicRanges
13317 Finally, you can also import R packages that have not yet been published on
13318 CRAN or Bioconductor as long as they are in a git repository. Use
13319 @option{--archive=git} followed by the URL of the git repository:
13322 guix import cran --archive=git https://github.com/immunogenomics/harmony
13328 Import TeX package information from the TeX Live package database for
13329 TeX packages that are part of the @uref{https://www.tug.org/texlive/,
13330 TeX Live distribution}.
13332 Information about the package is obtained from the TeX Live package
13333 database, a plain text file that is included in the @code{texlive-bin}
13334 package. The source code is downloaded from possibly multiple locations
13335 in the SVN repository of the Tex Live project.
13337 The command command below imports metadata for the @code{fontspec}
13341 guix import texlive fontspec
13345 @cindex JSON, import
13346 Import package metadata from a local JSON file. Consider the following
13347 example package definition in JSON format:
13353 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
13354 "build-system": "gnu",
13355 "home-page": "https://www.gnu.org/software/hello/",
13356 "synopsis": "Hello, GNU world: An example GNU package",
13357 "description": "GNU Hello prints a greeting.",
13358 "license": "GPL-3.0+",
13359 "native-inputs": ["gettext"]
13363 The field names are the same as for the @code{<package>} record
13364 (@xref{Defining Packages}). References to other packages are provided
13365 as JSON lists of quoted package specification strings such as
13366 @code{guile} or @code{guile@@2.0}.
13368 The importer also supports a more explicit source definition using the
13369 common fields for @code{<origin>} records:
13375 "method": "url-fetch",
13376 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
13378 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
13385 The command below reads metadata from the JSON file @code{hello.json}
13386 and outputs a package expression:
13389 guix import json hello.json
13394 Import metadata from the Haskell community's central package archive
13395 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
13396 Cabal files and includes all the relevant information, including package
13399 Specific command-line options are:
13404 Read a Cabal file from standard input.
13405 @item --no-test-dependencies
13407 Do not include dependencies required only by the test suites.
13408 @item --cabal-environment=@var{alist}
13409 @itemx -e @var{alist}
13410 @var{alist} is a Scheme alist defining the environment in which the
13411 Cabal conditionals are evaluated. The accepted keys are: @code{os},
13412 @code{arch}, @code{impl} and a string representing the name of a flag.
13413 The value associated with a flag has to be either the symbol
13414 @code{true} or @code{false}. The value associated with other keys
13415 has to conform to the Cabal file format definition. The default value
13416 associated with the keys @code{os}, @code{arch} and @code{impl} is
13417 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
13420 Traverse the dependency graph of the given upstream package recursively
13421 and generate package expressions for all those packages that are not yet
13425 The command below imports metadata for the latest version of the
13426 HTTP Haskell package without including test dependencies and
13427 specifying the value of the flag @samp{network-uri} as @code{false}:
13430 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
13433 A specific package version may optionally be specified by following the
13434 package name by an at-sign and a version number as in the following example:
13437 guix import hackage mtl@@2.1.3.1
13442 The @code{stackage} importer is a wrapper around the @code{hackage} one.
13443 It takes a package name, looks up the package version included in a
13444 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
13445 release and uses the @code{hackage} importer to retrieve its metadata.
13446 Note that it is up to you to select an LTS release compatible with the
13447 GHC compiler used by Guix.
13449 Specific command-line options are:
13452 @item --no-test-dependencies
13454 Do not include dependencies required only by the test suites.
13455 @item --lts-version=@var{version}
13456 @itemx -l @var{version}
13457 @var{version} is the desired LTS release version. If omitted the latest
13461 Traverse the dependency graph of the given upstream package recursively
13462 and generate package expressions for all those packages that are not yet
13466 The command below imports metadata for the HTTP Haskell package
13467 included in the LTS Stackage release version 7.18:
13470 guix import stackage --lts-version=7.18 HTTP
13475 Import metadata from an Emacs Lisp Package Archive (ELPA) package
13476 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
13478 Specific command-line options are:
13481 @item --archive=@var{repo}
13482 @itemx -a @var{repo}
13483 @var{repo} identifies the archive repository from which to retrieve the
13484 information. Currently the supported repositories and their identifiers
13488 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
13489 identifier. This is the default.
13491 Packages from @code{elpa.gnu.org} are signed with one of the keys
13492 contained in the GnuPG keyring at
13493 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
13494 @code{emacs} package (@pxref{Package Installation, ELPA package
13495 signatures,, emacs, The GNU Emacs Manual}).
13498 @uref{https://elpa.nongnu.org/nongnu/, NonGNU}, selected by the
13499 @code{nongnu} identifier.
13502 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
13503 @code{melpa-stable} identifier.
13506 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
13512 Traverse the dependency graph of the given upstream package recursively
13513 and generate package expressions for all those packages that are not yet
13519 Import metadata from the crates.io Rust package repository
13520 @uref{https://crates.io, crates.io}, as in this example:
13523 guix import crate blake2-rfc
13526 The crate importer also allows you to specify a version string:
13529 guix import crate constant-time-eq@@0.1.0
13532 Additional options include:
13537 Traverse the dependency graph of the given upstream package recursively
13538 and generate package expressions for all those packages that are not yet
13544 Import metadata from the Elm package repository
13545 @uref{https://package.elm-lang.org, package.elm-lang.org}, as in this example:
13548 guix import elm elm-explorations/webgl
13551 The Elm importer also allows you to specify a version string:
13554 guix import elm elm-explorations/webgl@@1.1.3
13557 Additional options include:
13562 Traverse the dependency graph of the given upstream package recursively
13563 and generate package expressions for all those packages that are not yet
13570 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
13571 repository used by the OCaml community.
13573 Additional options include:
13578 Traverse the dependency graph of the given upstream package recursively
13579 and generate package expressions for all those packages that are not yet
13582 By default, packages are searched in the official OPAM repository. This
13583 option, which can be used more than once, lets you add other repositories
13584 which will be searched for packages. It accepts as valid arguments:
13587 @item the name of a known repository - can be one of @code{opam},
13588 @code{coq} (equivalent to @code{coq-released}),
13589 @code{coq-core-dev}, @code{coq-extra-dev} or @code{grew}.
13590 @item the URL of a repository as expected by the
13591 @code{opam repository add} command (for instance, the URL equivalent
13592 of the above @code{opam} name would be
13593 @uref{https://opam.ocaml.org}).
13594 @item the path to a local copy of a repository (a directory containing a
13595 @file{packages/} sub-directory).
13598 Repositories are assumed to be passed to this option by order of
13599 preference. The additional repositories will not replace the default
13600 @code{opam} repository, which is always kept as a fallback.
13602 Also, please note that versions are not compared across repositories.
13603 The first repository (from left to right) that has at least one version
13604 of a given package will prevail over any others, and the version
13605 imported will be the latest one found @emph{in this repository only}.
13611 Import metadata for a Go module using
13612 @uref{https://proxy.golang.org, proxy.golang.org}.
13615 guix import go gopkg.in/yaml.v2
13618 It is possible to use a package specification with a @code{@@VERSION}
13619 suffix to import a specific version.
13621 Additional options include:
13626 Traverse the dependency graph of the given upstream package recursively
13627 and generate package expressions for all those packages that are not yet
13629 @item --pin-versions
13630 When using this option, the importer preserves the exact versions of the
13631 Go modules dependencies instead of using their latest available
13632 versions. This can be useful when attempting to import packages that
13633 recursively depend on former versions of themselves to build. When
13634 using this mode, the symbol of the package is made by appending the
13635 version to its name, so that multiple versions of the same package can
13641 Import metadata for @uref{https://wiki.call-cc.org/eggs, CHICKEN eggs}.
13642 The information is taken from @file{PACKAGE.egg} files found in the
13643 @uref{git://code.call-cc.org/eggs-5-all, eggs-5-all} Git
13644 repository. However, it does not provide all the information that we
13645 need, there is no ``description'' field, and the licenses used are not
13646 always precise (BSD is often used instead of BSD-N).
13649 guix import egg sourcehut
13652 You can also ask for a specific version:
13655 guix import egg arrays@@1.0
13658 Additional options include:
13662 Traverse the dependency graph of the given upstream package recursively
13663 and generate package expressions for all those packages that are not yet
13669 Import metadata from the hex.pm Erlang and Elixir package repository
13670 @uref{https://hex.pm, hex.pm}, as in this example:
13673 guix import hexpm stun
13676 The importer tries to determine the build system used by the package.
13678 The hexpm importer also allows you to specify a version string:
13681 guix import hexpm cf@@0.3.0
13684 Additional options include:
13689 Traverse the dependency graph of the given upstream package recursively
13690 and generate package expressions for all those packages that are not yet
13695 The structure of the @command{guix import} code is modular. It would be
13696 useful to have more importers for other package formats, and your help
13697 is welcome here (@pxref{Contributing}).
13699 @node Invoking guix refresh
13700 @section Invoking @command{guix refresh}
13702 @cindex @command {guix refresh}
13703 The primary audience of the @command{guix refresh} command is packagers.
13704 As a user, you may be interested in the @option{--with-latest} option,
13705 which can bring you package update superpowers built upon @command{guix
13706 refresh} (@pxref{Package Transformation Options,
13707 @option{--with-latest}}). By default, @command{guix refresh} reports
13708 any packages provided by the distribution that are outdated compared to
13709 the latest upstream version, like this:
13713 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
13714 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
13717 Alternatively, one can specify packages to consider, in which case a
13718 warning is emitted for packages that lack an updater:
13721 $ guix refresh coreutils guile guile-ssh
13722 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
13723 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
13726 @command{guix refresh} browses the upstream repository of each package and determines
13727 the highest version number of the releases therein. The command
13728 knows how to update specific types of packages: GNU packages, ELPA
13729 packages, etc.---see the documentation for @option{--type} below. There
13730 are many packages, though, for which it lacks a method to determine
13731 whether a new upstream release is available. However, the mechanism is
13732 extensible, so feel free to get in touch with us to add a new method!
13737 Consider the packages specified, and all the packages upon which they depend.
13740 $ guix refresh --recursive coreutils
13741 gnu/packages/acl.scm:40:13: acl would be upgraded from 2.2.53 to 2.3.1
13742 gnu/packages/m4.scm:30:12: 1.4.18 is already the latest version of m4
13743 gnu/packages/xml.scm:68:2: warning: no updater for expat
13744 gnu/packages/multiprecision.scm:40:12: 6.1.2 is already the latest version of gmp
13750 Sometimes the upstream name differs from the package name used in Guix,
13751 and @command{guix refresh} needs a little help. Most updaters honor the
13752 @code{upstream-name} property in package definitions, which can be used
13756 (define-public network-manager
13758 (name "network-manager")
13760 (properties '((upstream-name . "NetworkManager")))))
13763 When passed @option{--update}, it modifies distribution source files to
13764 update the version numbers and source tarball hashes of those package
13765 recipes (@pxref{Defining Packages}). This is achieved by downloading
13766 each package's latest source tarball and its associated OpenPGP
13767 signature, authenticating the downloaded tarball against its signature
13768 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
13769 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
13772 key used to sign the tarball is missing from the user's keyring, an
13773 attempt is made to automatically retrieve it from a public key server;
13774 when this is successful, the key is added to the user's keyring; otherwise,
13775 @command{guix refresh} reports an error.
13777 The following options are supported:
13781 @item --expression=@var{expr}
13782 @itemx -e @var{expr}
13783 Consider the package @var{expr} evaluates to.
13785 This is useful to precisely refer to a package, as in this example:
13788 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
13791 This command lists the dependents of the ``final'' libc (essentially all
13796 Update distribution source files (package recipes) in place. This is
13797 usually run from a checkout of the Guix source tree (@pxref{Running
13798 Guix Before It Is Installed}):
13801 $ ./pre-inst-env guix refresh -s non-core -u
13804 @xref{Defining Packages}, for more information on package definitions.
13806 @item --select=[@var{subset}]
13807 @itemx -s @var{subset}
13808 Select all the packages in @var{subset}, one of @code{core} or
13811 The @code{core} subset refers to all the packages at the core of the
13812 distribution---i.e., packages that are used to build ``everything
13813 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
13814 changing one of these packages in the distribution entails a rebuild of
13815 all the others. Thus, such updates are an inconvenience to users in
13816 terms of build time or bandwidth used to achieve the upgrade.
13818 The @code{non-core} subset refers to the remaining packages. It is
13819 typically useful in cases where an update of the core packages would be
13822 @item --manifest=@var{file}
13823 @itemx -m @var{file}
13824 Select all the packages from the manifest in @var{file}. This is useful to
13825 check if any packages of the user manifest can be updated.
13827 @item --type=@var{updater}
13828 @itemx -t @var{updater}
13829 Select only packages handled by @var{updater} (may be a comma-separated
13830 list of updaters). Currently, @var{updater} may be one of:
13834 the updater for GNU packages;
13836 the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
13838 the updater for packages hosted at @uref{https://sourceforge.net, SourceForge};
13840 the updater for GNOME packages;
13842 the updater for KDE packages;
13844 the updater for X.org packages;
13846 the updater for packages hosted on kernel.org;
13848 the updater for @uref{https://wiki.call-cc.org/eggs/, Egg} packages;
13850 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
13852 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
13854 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
13856 the updater for @uref{https://www.cpan.org/, CPAN} packages;
13858 the updater for @uref{https://pypi.python.org, PyPI} packages.
13860 the updater for @uref{https://rubygems.org, RubyGems} packages.
13862 the updater for @uref{https://github.com, GitHub} packages.
13864 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
13866 the updater for @uref{https://www.stackage.org, Stackage} packages.
13868 the updater for @uref{https://crates.io, Crates} packages.
13870 the updater for @uref{https://launchpad.net, Launchpad} packages.
13872 a generic updater that crawls the HTML page where the source tarball of
13873 the package is hosted, when applicable.
13876 a generic updater for packages hosted on Git repositories. It tries to
13877 be smart about parsing Git tag names, but if it is not able to parse the
13878 tag name and compare tags correctly, users can define the following
13879 properties for a package.
13882 @item @code{release-tag-prefix}: a regular expression for matching a prefix of
13885 @item @code{release-tag-suffix}: a regular expression for matching a suffix of
13888 @item @code{release-tag-version-delimiter}: a string used as the delimiter in
13889 the tag name for separating the numbers of the version.
13891 @item @code{accept-pre-releases}: by default, the updater will ignore
13892 pre-releases; to make it also look for pre-releases, set the this
13893 property to @code{#t}.
13902 '((release-tag-prefix . "^release0-")
13903 (release-tag-suffix . "[a-z]?$")
13904 (release-tag-version-delimiter . ":"))))
13910 For instance, the following command only checks for updates of Emacs
13911 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
13914 $ guix refresh --type=elpa,cran
13915 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
13916 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
13919 @item --list-updaters
13920 List available updaters and exit (see @option{--type} above).
13922 For each updater, display the fraction of packages it covers; at the
13923 end, display the fraction of packages covered by all these updaters.
13926 In addition, @command{guix refresh} can be passed one or more package
13927 names, as in this example:
13930 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
13934 The command above specifically updates the @code{emacs} and
13935 @code{idutils} packages. The @option{--select} option would have no
13936 effect in this case. You might also want to update definitions that
13937 correspond to the packages installed in your profile:
13940 $ ./pre-inst-env guix refresh -u \
13941 $(guix package --list-installed | cut -f1)
13944 When considering whether to upgrade a package, it is sometimes
13945 convenient to know which packages would be affected by the upgrade and
13946 should be checked for compatibility. For this the following option may
13947 be used when passing @command{guix refresh} one or more package names:
13951 @item --list-dependent
13953 List top-level dependent packages that would need to be rebuilt as a
13954 result of upgrading one or more packages.
13956 @xref{Invoking guix graph, the @code{reverse-package} type of
13957 @command{guix graph}}, for information on how to visualize the list of
13958 dependents of a package.
13962 Be aware that the @option{--list-dependent} option only
13963 @emph{approximates} the rebuilds that would be required as a result of
13964 an upgrade. More rebuilds might be required under some circumstances.
13967 $ guix refresh --list-dependent flex
13968 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
13969 hop@@2.4.0 emacs-geiser@@0.13 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
13972 The command above lists a set of packages that could be built to check
13973 for compatibility with an upgraded @code{flex} package.
13977 @item --list-transitive
13978 List all the packages which one or more packages depend upon.
13981 $ guix refresh --list-transitive flex
13982 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
13983 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{}
13988 The command above lists a set of packages which, when changed, would cause
13989 @code{flex} to be rebuilt.
13991 The following options can be used to customize GnuPG operation:
13995 @item --gpg=@var{command}
13996 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
13997 for in @code{$PATH}.
13999 @item --keyring=@var{file}
14000 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
14001 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
14002 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
14003 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
14004 information on a tool to manipulate keybox files).
14006 When this option is omitted, @command{guix refresh} uses
14007 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
14008 signing keys. OpenPGP signatures are checked against keys from this keyring;
14009 missing keys are downloaded to this keyring as well (see
14010 @option{--key-download} below).
14012 You can export keys from your default GPG keyring into a keybox file using
14013 commands like this one:
14016 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
14019 Likewise, you can fetch keys to a specific keybox file like this:
14022 gpg --no-default-keyring --keyring mykeyring.kbx \
14023 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
14026 @xref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
14027 Privacy Guard}, for more information on GPG's @option{--keyring} option.
14029 @item --key-download=@var{policy}
14030 Handle missing OpenPGP keys according to @var{policy}, which may be one
14035 Always download missing OpenPGP keys from the key server, and add them
14036 to the user's GnuPG keyring.
14039 Never try to download missing OpenPGP keys. Instead just bail out.
14042 When a package signed with an unknown OpenPGP key is encountered, ask
14043 the user whether to download it or not. This is the default behavior.
14046 @item --key-server=@var{host}
14047 Use @var{host} as the OpenPGP key server when importing a public key.
14049 @item --load-path=@var{directory}
14050 @itemx -L @var{directory}
14051 Add @var{directory} to the front of the package module search path
14052 (@pxref{Package Modules}).
14054 This allows users to define their own packages and make them visible to
14055 the command-line tools.
14059 The @code{github} updater uses the
14060 @uref{https://developer.github.com/v3/, GitHub API} to query for new
14061 releases. When used repeatedly e.g.@: when refreshing all packages,
14062 GitHub will eventually refuse to answer any further API requests. By
14063 default 60 API requests per hour are allowed, and a full refresh on all
14064 GitHub packages in Guix requires more than this. Authentication with
14065 GitHub through the use of an API token alleviates these limits. To use
14066 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
14067 token procured from @uref{https://github.com/settings/tokens} or
14071 @node Invoking guix style
14072 @section Invoking @command{guix style}
14074 The @command{guix style} command helps users and packagers alike style
14075 their package definitions and configuration files according to the
14076 latest fashionable trends. It can either reformat whole files, with the
14077 @option{--whole-file} option, or apply specific @dfn{styling rules} to
14078 individual package definitions. The command currently provides the
14079 following styling rules:
14083 formatting package definitions according to the project's conventions
14084 (@pxref{Formatting Code});
14087 rewriting package inputs to the ``new style'', as explained below.
14090 The way package inputs are written is going through a transition
14091 (@pxref{package Reference}, for more on package inputs). Until version
14092 1.3.0, package inputs were written using the ``old style'', where each
14093 input was given an explicit label, most of the time the package name:
14098 ;; The "old style" (deprecated).
14099 (inputs `(("libunistring" ,libunistring)
14100 ("libffi" ,libffi))))
14103 Today, the old style is deprecated and the preferred style looks like
14109 ;; The "new style".
14110 (inputs (list libunistring libffi)))
14113 Likewise, uses of @code{alist-delete} and friends to manipulate inputs
14114 is now deprecated in favor of @code{modify-inputs} (@pxref{Defining
14115 Package Variants}, for more info on @code{modify-inputs}).
14117 In the vast majority of cases, this is a purely mechanical change on the
14118 surface syntax that does not even incur a package rebuild. Running
14119 @command{guix style -S inputs} can do that for you, whether you're working on
14120 packages in Guix proper or in an external channel.
14122 The general syntax is:
14125 guix style [@var{options}] @var{package}@dots{}
14128 This causes @command{guix style} to analyze and rewrite the definition
14129 of @var{package}@dots{} or, when @var{package} is omitted, of @emph{all}
14130 the packages. The @option{--styling} or @option{-S} option allows you
14131 to select the style rule, the default rule being @code{format}---see
14134 To reformat entire source files, the syntax is:
14137 guix style --whole-file @var{file}@dots{}
14140 The available options are listed below.
14145 Show source file locations that would be edited but do not modify them.
14149 Reformat the given files in their entirety. In that case, subsequent
14150 arguments are interpreted as file names (rather than package names), and
14151 the @option{--styling} option has no effect.
14153 As an example, here is how you might reformat your operating system
14154 configuration (you need write permissions for the file):
14157 guix style -f /etc/config.scm
14160 @item --styling=@var{rule}
14161 @itemx -S @var{rule}
14162 Apply @var{rule}, one of the following styling rules:
14166 Format the given package definition(s)---this is the default styling
14167 rule. For example, a packager running Guix on a checkout
14168 (@pxref{Running Guix Before It Is Installed}) might want to reformat the
14169 definition of the Coreutils package like so:
14172 ./pre-inst-env guix style coreutils
14176 Rewrite package inputs to the ``new style'', as described above. This
14177 is how you would rewrite inputs of package @code{whatnot} in your own
14181 guix style -L ~/my/channel -S inputs whatnot
14184 Rewriting is done in a conservative way: preserving comments and bailing
14185 out if it cannot make sense of the code that appears in an inputs field.
14186 The @option{--input-simplification} option described below provides
14187 fine-grain control over when inputs should be simplified.
14190 @item --list-stylings
14192 List and describe the available styling rules and exit.
14194 @item --load-path=@var{directory}
14195 @itemx -L @var{directory}
14196 Add @var{directory} to the front of the package module search path
14197 (@pxref{Package Modules}).
14199 @item --expression=@var{expr}
14200 @itemx -e @var{expr}
14201 Style the package @var{expr} evaluates to.
14203 For example, running:
14206 guix style -e '(@@ (gnu packages gcc) gcc-5)'
14209 styles the @code{gcc-5} package definition.
14211 @item --input-simplification=@var{policy}
14212 When using the @code{inputs} styling rule, with @samp{-S inputs}, this
14213 option specifies the package input simplification policy for cases where
14214 an input label does not match the corresponding package name.
14215 @var{policy} may be one of the following:
14219 Simplify inputs only when the change is ``silent'', meaning that the
14220 package does not need to be rebuilt (its derivation is unchanged).
14223 Simplify inputs only when that is ``safe'' to do: the package might need
14224 to be rebuilt, but the change is known to have no observable effect.
14227 Simplify inputs even when input labels do not match package names, and
14228 even if that might have an observable effect.
14231 The default is @code{silent}, meaning that input simplifications do not
14232 trigger any package rebuild.
14235 @node Invoking guix lint
14236 @section Invoking @command{guix lint}
14238 @cindex @command{guix lint}
14239 @cindex package, checking for errors
14240 The @command{guix lint} command is meant to help package developers avoid
14241 common errors and use a consistent style. It runs a number of checks on
14242 a given set of packages in order to find common mistakes in their
14243 definitions. Available @dfn{checkers} include (see
14244 @option{--list-checkers} for a complete list):
14249 Validate certain typographical and stylistic rules about package
14250 descriptions and synopses.
14252 @item inputs-should-be-native
14253 Identify inputs that should most likely be native inputs.
14259 @itemx source-file-name
14260 Probe @code{home-page} and @code{source} URLs and report those that are
14261 invalid. Suggest a @code{mirror://} URL when applicable. If the
14262 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
14263 URL@. Check that the source file name is meaningful, e.g.@: is not just a
14264 version number or ``git-checkout'', without a declared @code{file-name}
14265 (@pxref{origin Reference}).
14267 @item source-unstable-tarball
14268 Parse the @code{source} URL to determine if a tarball from GitHub is
14269 autogenerated or if it is a release tarball. Unfortunately GitHub's
14270 autogenerated tarballs are sometimes regenerated.
14273 Check that the derivation of the given packages can be successfully
14274 computed for all the supported systems (@pxref{Derivations}).
14276 @item profile-collisions
14277 Check whether installing the given packages in a profile would lead to
14278 collisions. Collisions occur when several packages with the same name
14279 but a different version or a different store file name are propagated.
14280 @xref{package Reference, @code{propagated-inputs}}, for more information
14281 on propagated inputs.
14284 @cindex Software Heritage, source code archive
14285 @cindex archival of source code, Software Heritage
14286 Checks whether the package's source code is archived at
14287 @uref{https://www.softwareheritage.org, Software Heritage}.
14289 When the source code that is not archived comes from a version-control system
14290 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
14291 ``save'' request so that it eventually archives it. This ensures that the
14292 source will remain available in the long term, and that Guix can fall back to
14293 Software Heritage should the source code disappear from its original host.
14294 The status of recent ``save'' requests can be
14295 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
14297 When source code is a tarball obtained with @code{url-fetch}, simply print a
14298 message when it is not archived. As of this writing, Software Heritage does
14299 not allow requests to save arbitrary tarballs; we are working on ways to
14300 ensure that non-VCS source code is also archived.
14303 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
14304 request rate per IP address}. When the limit is reached, @command{guix lint}
14305 prints a message and the @code{archival} checker stops doing anything until
14306 that limit has been reset.
14309 @cindex security vulnerabilities
14310 @cindex CVE, Common Vulnerabilities and Exposures
14311 Report known vulnerabilities found in the Common Vulnerabilities and
14312 Exposures (CVE) databases of the current and past year
14313 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
14316 To view information about a particular vulnerability, visit pages such as:
14320 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
14322 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
14326 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
14327 @code{CVE-2015-7554}.
14329 Package developers can specify in package recipes the
14330 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
14331 name and version of the package when they differ from the name or version
14332 that Guix uses, as in this example:
14338 ;; CPE calls this package "grub2".
14339 (properties '((cpe-name . "grub2")
14340 (cpe-version . "2.3"))))
14343 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
14344 Some entries in the CVE database do not specify which version of a
14345 package they apply to, and would thus ``stick around'' forever. Package
14346 developers who found CVE alerts and verified they can be ignored can
14347 declare them as in this example:
14353 ;; These CVEs no longer apply and can be safely ignored.
14354 (properties `((lint-hidden-cve . ("CVE-2011-0433"
14357 "CVE-2011-5244")))))
14361 Warn about obvious source code formatting issues: trailing white space,
14362 use of tabulations, etc.
14365 Report old-style input labels that do not match the name of the
14366 corresponding package. This aims to help migrate from the ``old input
14367 style''. @xref{package Reference}, for more information on package
14368 inputs and input styles. @xref{Invoking guix style}, on how to migrate
14372 The general syntax is:
14375 guix lint @var{options} @var{package}@dots{}
14378 If no package is given on the command line, then all packages are checked.
14379 The @var{options} may be zero or more of the following:
14382 @item --list-checkers
14384 List and describe all the available checkers that will be run on packages
14389 Only enable the checkers specified in a comma-separated list using the
14390 names returned by @option{--list-checkers}.
14394 Only disable the checkers specified in a comma-separated list using the
14395 names returned by @option{--list-checkers}.
14397 @item --expression=@var{expr}
14398 @itemx -e @var{expr}
14399 Consider the package @var{expr} evaluates to.
14401 This is useful to unambiguously designate packages, as in this example:
14404 guix lint -c archival -e '(@@ (gnu packages guile) guile-3.0)'
14409 Only enable the checkers that do not depend on Internet access.
14411 @item --load-path=@var{directory}
14412 @itemx -L @var{directory}
14413 Add @var{directory} to the front of the package module search path
14414 (@pxref{Package Modules}).
14416 This allows users to define their own packages and make them visible to
14417 the command-line tools.
14421 @node Invoking guix size
14422 @section Invoking @command{guix size}
14425 @cindex package size
14427 @cindex @command{guix size}
14428 The @command{guix size} command helps package developers profile the
14429 disk usage of packages. It is easy to overlook the impact of an
14430 additional dependency added to a package, or the impact of using a
14431 single output for a package that could easily be split (@pxref{Packages
14432 with Multiple Outputs}). Such are the typical issues that
14433 @command{guix size} can highlight.
14435 The command can be passed one or more package specifications
14436 such as @code{gcc@@4.8}
14437 or @code{guile:debug}, or a file name in the store. Consider this
14441 $ guix size coreutils
14442 store item total self
14443 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
14444 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
14445 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
14446 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
14447 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
14448 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
14449 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
14450 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
14455 The store items listed here constitute the @dfn{transitive closure} of
14456 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
14457 would be returned by:
14460 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
14463 Here the output shows three columns next to store items. The first column,
14464 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
14465 the store item---that is, its own size plus the size of all its
14466 dependencies. The next column, labeled ``self'', shows the size of the
14467 item itself. The last column shows the ratio of the size of the item
14468 itself to the space occupied by all the items listed here.
14470 In this example, we see that the closure of Coreutils weighs in at
14471 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
14472 libraries. (That libc and GCC's libraries represent a large fraction of
14473 the closure is not a problem @i{per se} because they are always available
14474 on the system anyway.)
14476 Since the command also accepts store file names, assessing the size of
14477 a build result is straightforward:
14480 guix size $(guix system build config.scm)
14483 When the package(s) passed to @command{guix size} are available in the
14484 store@footnote{More precisely, @command{guix size} looks for the
14485 @emph{ungrafted} variant of the given package(s), as returned by
14486 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
14487 for information on grafts.}, @command{guix size} queries the daemon to determine its
14488 dependencies, and measures its size in the store, similar to @command{du
14489 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
14492 When the given packages are @emph{not} in the store, @command{guix size}
14493 reports information based on the available substitutes
14494 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
14495 store items that are not even on disk, only available remotely.
14497 You can also specify several package names:
14500 $ guix size coreutils grep sed bash
14501 store item total self
14502 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
14503 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
14504 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
14505 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
14511 In this example we see that the combination of the four packages takes
14512 102.3@tie{}MiB in total, which is much less than the sum of each closure
14513 since they have a lot of dependencies in common.
14515 When looking at the profile returned by @command{guix size}, you may
14516 find yourself wondering why a given package shows up in the profile at
14517 all. To understand it, you can use @command{guix graph --path -t
14518 references} to display the shortest path between the two packages
14519 (@pxref{Invoking guix graph}).
14521 The available options are:
14525 @item --substitute-urls=@var{urls}
14526 Use substitute information from @var{urls}.
14527 @xref{client-substitute-urls, the same option for @code{guix build}}.
14529 @item --sort=@var{key}
14530 Sort lines according to @var{key}, one of the following options:
14534 the size of each item (the default);
14536 the total size of the item's closure.
14539 @item --map-file=@var{file}
14540 Write a graphical map of disk usage in PNG format to @var{file}.
14542 For the example above, the map looks like this:
14544 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
14545 produced by @command{guix size}}
14547 This option requires that
14548 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
14549 installed and visible in Guile's module search path. When that is not
14550 the case, @command{guix size} fails as it tries to load it.
14552 @item --system=@var{system}
14553 @itemx -s @var{system}
14554 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
14556 @item --load-path=@var{directory}
14557 @itemx -L @var{directory}
14558 Add @var{directory} to the front of the package module search path
14559 (@pxref{Package Modules}).
14561 This allows users to define their own packages and make them visible to
14562 the command-line tools.
14565 @node Invoking guix graph
14566 @section Invoking @command{guix graph}
14569 @cindex @command{guix graph}
14570 @cindex package dependencies
14571 Packages and their dependencies form a @dfn{graph}, specifically a
14572 directed acyclic graph (DAG). It can quickly become difficult to have a
14573 mental model of the package DAG, so the @command{guix graph} command
14574 provides a visual representation of the DAG@. By default,
14575 @command{guix graph} emits a DAG representation in the input format of
14576 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
14577 directly to the @command{dot} command of Graphviz. It can also emit an
14578 HTML page with embedded JavaScript code to display a ``chord diagram''
14579 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
14580 emit Cypher queries to construct a graph in a graph database supporting
14581 the @uref{https://www.opencypher.org/, openCypher} query language. With
14582 @option{--path}, it simply displays the shortest path between two
14583 packages. The general syntax is:
14586 guix graph @var{options} @var{package}@dots{}
14589 For example, the following command generates a PDF file representing the
14590 package DAG for the GNU@tie{}Core Utilities, showing its build-time
14594 guix graph coreutils | dot -Tpdf > dag.pdf
14597 The output looks like this:
14599 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
14601 Nice little graph, no?
14603 You may find it more pleasant to navigate the graph interactively with
14604 @command{xdot} (from the @code{xdot} package):
14607 guix graph coreutils | xdot -
14610 But there is more than one graph! The one above is concise: it is the
14611 graph of package objects, omitting implicit inputs such as GCC, libc,
14612 grep, etc. It is often useful to have such a concise graph, but
14613 sometimes one may want to see more details. @command{guix graph} supports
14614 several types of graphs, allowing you to choose the level of detail:
14618 This is the default type used in the example above. It shows the DAG of
14619 package objects, excluding implicit dependencies. It is concise, but
14620 filters out many details.
14622 @item reverse-package
14623 This shows the @emph{reverse} DAG of packages. For example:
14626 guix graph --type=reverse-package ocaml
14629 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
14630 you are also interested in cases where OCaml is an implicit dependency, see
14631 @code{reverse-bag} below).
14633 Note that for core packages this can yield huge graphs. If all you want
14634 is to know the number of packages that depend on a given package, use
14635 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
14636 @option{--list-dependent}}).
14639 This is the package DAG, @emph{including} implicit inputs.
14641 For instance, the following command:
14644 guix graph --type=bag-emerged coreutils
14647 ...@: yields this bigger graph:
14649 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
14651 At the bottom of the graph, we see all the implicit inputs of
14652 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
14654 Now, note that the dependencies of these implicit inputs---that is, the
14655 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
14656 here, for conciseness.
14659 Similar to @code{bag-emerged}, but this time including all the bootstrap
14662 @item bag-with-origins
14663 Similar to @code{bag}, but also showing origins and their dependencies.
14666 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
14667 it also takes implicit dependencies into account. For example:
14670 guix graph -t reverse-bag dune
14674 ...@: yields the graph of all packages that depend on Dune, directly or
14675 indirectly. Since Dune is an @emph{implicit} dependency of many packages
14676 @i{via} @code{dune-build-system}, this shows a large number of packages,
14677 whereas @code{reverse-package} would show very few if any.
14680 This is the most detailed representation: It shows the DAG of
14681 derivations (@pxref{Derivations}) and plain store items. Compared to
14682 the above representation, many additional nodes are visible, including
14683 build scripts, patches, Guile modules, etc.
14685 For this type of graph, it is also possible to pass a @file{.drv} file
14686 name instead of a package name, as in:
14689 guix graph -t derivation $(guix system build -d my-config.scm)
14693 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
14694 For example, the following command shows the graph for the package
14695 module that defines the @code{guile} package:
14698 guix graph -t module guile | xdot -
14702 All the types above correspond to @emph{build-time dependencies}. The
14703 following graph type represents the @emph{run-time dependencies}:
14707 This is the graph of @dfn{references} of a package output, as returned
14708 by @command{guix gc --references} (@pxref{Invoking guix gc}).
14710 If the given package output is not available in the store, @command{guix
14711 graph} attempts to obtain dependency information from substitutes.
14713 Here you can also pass a store file name instead of a package name. For
14714 example, the command below produces the reference graph of your profile
14715 (which can be big!):
14718 guix graph -t references $(readlink -f ~/.guix-profile)
14722 This is the graph of the @dfn{referrers} of a store item, as returned by
14723 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
14725 This relies exclusively on local information from your store. For
14726 instance, let us suppose that the current Inkscape is available in 10
14727 profiles on your machine; @command{guix graph -t referrers inkscape}
14728 will show a graph rooted at Inkscape and with those 10 profiles linked
14731 It can help determine what is preventing a store item from being garbage
14736 @cindex shortest path, between packages
14737 Often, the graph of the package you are interested in does not fit on
14738 your screen, and anyway all you want to know is @emph{why} that package
14739 actually depends on some seemingly unrelated package. The
14740 @option{--path} option instructs @command{guix graph} to display the
14741 shortest path between two packages (or derivations, or store items,
14745 $ guix graph --path emacs libunistring
14748 libunistring@@0.9.10
14749 $ guix graph --path -t derivation emacs libunistring
14750 /gnu/store/@dots{}-emacs-26.3.drv
14751 /gnu/store/@dots{}-mailutils-3.9.drv
14752 /gnu/store/@dots{}-libunistring-0.9.10.drv
14753 $ guix graph --path -t references emacs libunistring
14754 /gnu/store/@dots{}-emacs-26.3
14755 /gnu/store/@dots{}-libidn2-2.2.0
14756 /gnu/store/@dots{}-libunistring-0.9.10
14759 Sometimes you still want to visualize the graph but would like to trim
14760 it so it can actually be displayed. One way to do it is via the
14761 @option{--max-depth} (or @option{-M}) option, which lets you specify the
14762 maximum depth of the graph. In the example below, we visualize only
14763 @code{libreoffice} and the nodes whose distance to @code{libreoffice} is
14767 guix graph -M 2 libreoffice | xdot -f fdp -
14770 Mind you, that's still a big ball of spaghetti, but at least
14771 @command{dot} can render it quickly and it can be browsed somewhat.
14773 The available options are the following:
14776 @item --type=@var{type}
14777 @itemx -t @var{type}
14778 Produce a graph output of @var{type}, where @var{type} must be one of
14779 the values listed above.
14782 List the supported graph types.
14784 @item --backend=@var{backend}
14785 @itemx -b @var{backend}
14786 Produce a graph using the selected @var{backend}.
14788 @item --list-backends
14789 List the supported graph backends.
14791 Currently, the available backends are Graphviz and d3.js.
14794 Display the shortest path between two nodes of the type specified by
14795 @option{--type}. The example below shows the shortest path between
14796 @code{libreoffice} and @code{llvm} according to the references of
14797 @code{libreoffice}:
14800 $ guix graph --path -t references libreoffice llvm
14801 /gnu/store/@dots{}-libreoffice-6.4.2.2
14802 /gnu/store/@dots{}-libepoxy-1.5.4
14803 /gnu/store/@dots{}-mesa-19.3.4
14804 /gnu/store/@dots{}-llvm-9.0.1
14807 @item --expression=@var{expr}
14808 @itemx -e @var{expr}
14809 Consider the package @var{expr} evaluates to.
14811 This is useful to precisely refer to a package, as in this example:
14814 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
14817 @item --system=@var{system}
14818 @itemx -s @var{system}
14819 Display the graph for @var{system}---e.g., @code{i686-linux}.
14821 The package dependency graph is largely architecture-independent, but there
14822 are some architecture-dependent bits that this option allows you to visualize.
14824 @item --load-path=@var{directory}
14825 @itemx -L @var{directory}
14826 Add @var{directory} to the front of the package module search path
14827 (@pxref{Package Modules}).
14829 This allows users to define their own packages and make them visible to
14830 the command-line tools.
14833 On top of that, @command{guix graph} supports all the usual package
14834 transformation options (@pxref{Package Transformation Options}). This
14835 makes it easy to view the effect of a graph-rewriting transformation
14836 such as @option{--with-input}. For example, the command below outputs
14837 the graph of @code{git} once @code{openssl} has been replaced by
14838 @code{libressl} everywhere in the graph:
14841 guix graph git --with-input=openssl=libressl
14844 So many possibilities, so much fun!
14846 @node Invoking guix publish
14847 @section Invoking @command{guix publish}
14849 @cindex @command{guix publish}
14850 The purpose of @command{guix publish} is to enable users to easily share
14851 their store with others, who can then use it as a substitute server
14852 (@pxref{Substitutes}).
14854 When @command{guix publish} runs, it spawns an HTTP server which allows
14855 anyone with network access to obtain substitutes from it. This means
14856 that any machine running Guix can also act as if it were a build farm,
14857 since the HTTP interface is compatible with Cuirass, the software behind
14858 the @code{@value{SUBSTITUTE-SERVER-1}} build farm.
14860 For security, each substitute is signed, allowing recipients to check
14861 their authenticity and integrity (@pxref{Substitutes}). Because
14862 @command{guix publish} uses the signing key of the system, which is only
14863 readable by the system administrator, it must be started as root; the
14864 @option{--user} option makes it drop root privileges early on.
14866 The signing key pair must be generated before @command{guix publish} is
14867 launched, using @command{guix archive --generate-key} (@pxref{Invoking
14870 When the @option{--advertise} option is passed, the server advertises
14871 its availability on the local network using multicast DNS (mDNS) and DNS
14872 service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
14873 guile-avahi, Using Avahi in Guile Scheme Programs}).
14875 The general syntax is:
14878 guix publish @var{options}@dots{}
14881 Running @command{guix publish} without any additional arguments will
14882 spawn an HTTP server on port 8080:
14888 @cindex socket activation, for @command{guix publish}
14889 @command{guix publish} can also be started following the systemd
14890 ``socket activation'' protocol (@pxref{Service De- and Constructors,
14891 @code{make-systemd-constructor},, shepherd, The GNU Shepherd Manual}).
14893 Once a publishing server has been authorized, the daemon may download
14894 substitutes from it. @xref{Getting Substitutes from Other Servers}.
14896 By default, @command{guix publish} compresses archives on the fly as it
14897 serves them. This ``on-the-fly'' mode is convenient in that it requires
14898 no setup and is immediately available. However, when serving lots of
14899 clients, we recommend using the @option{--cache} option, which enables
14900 caching of the archives before they are sent to clients---see below for
14901 details. The @command{guix weather} command provides a handy way to
14902 check what a server provides (@pxref{Invoking guix weather}).
14904 As a bonus, @command{guix publish} also serves as a content-addressed
14905 mirror for source files referenced in @code{origin} records
14906 (@pxref{origin Reference}). For instance, assuming @command{guix
14907 publish} is running on @code{example.org}, the following URL returns the
14908 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
14909 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
14912 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
14915 Obviously, these URLs only work for files that are in the store; in
14916 other cases, they return 404 (``Not Found'').
14918 @cindex build logs, publication
14919 Build logs are available from @code{/log} URLs like:
14922 http://example.org/log/gwspk@dots{}-guile-2.2.3
14926 When @command{guix-daemon} is configured to save compressed build logs,
14927 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
14928 URLs return the compressed log as-is, with an appropriate
14929 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
14930 running @command{guix-daemon} with @option{--log-compression=gzip} since
14931 Web browsers can automatically decompress it, which is not the case with
14934 The following options are available:
14937 @item --port=@var{port}
14938 @itemx -p @var{port}
14939 Listen for HTTP requests on @var{port}.
14941 @item --listen=@var{host}
14942 Listen on the network interface for @var{host}. The default is to
14943 accept connections from any interface.
14945 @item --user=@var{user}
14946 @itemx -u @var{user}
14947 Change privileges to @var{user} as soon as possible---i.e., once the
14948 server socket is open and the signing key has been read.
14950 @item --compression[=@var{method}[:@var{level}]]
14951 @itemx -C [@var{method}[:@var{level}]]
14952 Compress data using the given @var{method} and @var{level}. @var{method} is
14953 one of @code{lzip}, @code{zstd}, and @code{gzip}; when @var{method} is
14954 omitted, @code{gzip} is used.
14956 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
14957 to different compression levels: 1 is the fastest, and 9 is the best
14958 (CPU-intensive). The default is 3.
14960 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a
14961 small increase in CPU usage; see
14962 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip
14963 Web page}. However, @code{lzip} achieves low decompression throughput
14964 (on the order of 50@tie{}MiB/s on modern hardware), which can be a
14965 bottleneck for someone who downloads over a fast network connection.
14967 The compression ratio of @code{zstd} is between that of @code{lzip} and
14968 that of @code{gzip}; its main advantage is a
14969 @uref{https://facebook.github.io/zstd/,high decompression speed}.
14971 Unless @option{--cache} is used, compression occurs on the fly and
14972 the compressed streams are not
14973 cached. Thus, to reduce load on the machine that runs @command{guix
14974 publish}, it may be a good idea to choose a low compression level, to
14975 run @command{guix publish} behind a caching proxy, or to use
14976 @option{--cache}. Using @option{--cache} has the advantage that it
14977 allows @command{guix publish} to add @code{Content-Length} HTTP header
14980 This option can be repeated, in which case every substitute gets compressed
14981 using all the selected methods, and all of them are advertised. This is
14982 useful when users may not support all the compression methods: they can select
14983 the one they support.
14985 @item --cache=@var{directory}
14986 @itemx -c @var{directory}
14987 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
14988 and only serve archives that are in cache.
14990 When this option is omitted, archives and meta-data are created
14991 on-the-fly. This can reduce the available bandwidth, especially when
14992 compression is enabled, since this may become CPU-bound. Another
14993 drawback of the default mode is that the length of archives is not known
14994 in advance, so @command{guix publish} does not add a
14995 @code{Content-Length} HTTP header to its responses, which in turn
14996 prevents clients from knowing the amount of data being downloaded.
14998 Conversely, when @option{--cache} is used, the first request for a store
14999 item (@i{via} a @code{.narinfo} URL) triggers a
15000 background process to @dfn{bake} the archive---computing its
15001 @code{.narinfo} and compressing the archive, if needed. Once the
15002 archive is cached in @var{directory}, subsequent requests succeed and
15003 are served directly from the cache, which guarantees that clients get
15004 the best possible bandwidth.
15006 That first @code{.narinfo} request nonetheless returns 200, provided the
15007 requested store item is ``small enough'', below the cache bypass
15008 threshold---see @option{--cache-bypass-threshold} below. That way,
15009 clients do not have to wait until the archive is baked. For larger
15010 store items, the first @code{.narinfo} request returns 404, meaning that
15011 clients have to wait until the archive is baked.
15013 The ``baking'' process is performed by worker threads. By default, one
15014 thread per CPU core is created, but this can be customized. See
15015 @option{--workers} below.
15017 When @option{--ttl} is used, cached entries are automatically deleted
15018 when they have expired.
15020 @item --workers=@var{N}
15021 When @option{--cache} is used, request the allocation of @var{N} worker
15022 threads to ``bake'' archives.
15024 @item --ttl=@var{ttl}
15025 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
15026 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
15027 days, @code{1m} means 1 month, and so on.
15029 This allows the user's Guix to keep substitute information in cache for
15030 @var{ttl}. However, note that @code{guix publish} does not itself
15031 guarantee that the store items it provides will indeed remain available
15032 for as long as @var{ttl}.
15034 Additionally, when @option{--cache} is used, cached entries that have
15035 not been accessed for @var{ttl} and that no longer have a corresponding
15036 item in the store, may be deleted.
15038 @item --negative-ttl=@var{ttl}
15039 Similarly produce @code{Cache-Control} HTTP headers to advertise the
15040 time-to-live (TTL) of @emph{negative} lookups---missing store items, for
15041 which the HTTP 404 code is returned. By default, no negative TTL is
15044 This parameter can help adjust server load and substitute latency by
15045 instructing cooperating clients to be more or less patient when a store
15048 @item --cache-bypass-threshold=@var{size}
15049 When used in conjunction with @option{--cache}, store items smaller than
15050 @var{size} are immediately available, even when they are not yet in
15051 cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
15052 for megabytes and so on. The default is @code{10M}.
15054 ``Cache bypass'' allows you to reduce the publication delay for clients
15055 at the expense of possibly additional I/O and CPU use on the server
15056 side: depending on the client access patterns, those store items can end
15057 up being baked several times until a copy is available in cache.
15059 Increasing the threshold may be useful for sites that have few users, or
15060 to guarantee that users get substitutes even for store items that are
15063 @item --nar-path=@var{path}
15064 Use @var{path} as the prefix for the URLs of ``nar'' files
15065 (@pxref{Invoking guix archive, normalized archives}).
15067 By default, nars are served at a URL such as
15068 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
15069 change the @code{/nar} part to @var{path}.
15071 @item --public-key=@var{file}
15072 @itemx --private-key=@var{file}
15073 Use the specific @var{file}s as the public/private key pair used to sign
15074 the store items being published.
15076 The files must correspond to the same key pair (the private key is used
15077 for signing and the public key is merely advertised in the signature
15078 metadata). They must contain keys in the canonical s-expression format
15079 as produced by @command{guix archive --generate-key} (@pxref{Invoking
15080 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
15081 @file{/etc/guix/signing-key.sec} are used.
15083 @item --repl[=@var{port}]
15084 @itemx -r [@var{port}]
15085 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
15086 Reference Manual}) on @var{port} (37146 by default). This is used
15087 primarily for debugging a running @command{guix publish} server.
15090 Enabling @command{guix publish} on Guix System is a one-liner: just
15091 instantiate a @code{guix-publish-service-type} service in the @code{services} field
15092 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
15093 @code{guix-publish-service-type}}).
15095 If you are instead running Guix on a ``foreign distro'', follow these
15100 If your host distro uses the systemd init system:
15103 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
15104 /etc/systemd/system/
15105 # systemctl start guix-publish && systemctl enable guix-publish
15109 If your host distro uses the Upstart init system:
15112 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
15113 # start guix-publish
15117 Otherwise, proceed similarly with your distro's init system.
15120 @node Invoking guix challenge
15121 @section Invoking @command{guix challenge}
15123 @cindex reproducible builds
15124 @cindex verifiable builds
15125 @cindex @command{guix challenge}
15127 Do the binaries provided by this server really correspond to the source
15128 code it claims to build? Is a package build process deterministic?
15129 These are the questions the @command{guix challenge} command attempts to
15132 The former is obviously an important question: Before using a substitute
15133 server (@pxref{Substitutes}), one had better @emph{verify} that it
15134 provides the right binaries, and thus @emph{challenge} it. The latter
15135 is what enables the former: If package builds are deterministic, then
15136 independent builds of the package should yield the exact same result,
15137 bit for bit; if a server provides a binary different from the one
15138 obtained locally, it may be either corrupt or malicious.
15140 We know that the hash that shows up in @file{/gnu/store} file names is
15141 the hash of all the inputs of the process that built the file or
15142 directory---compilers, libraries, build scripts,
15143 etc. (@pxref{Introduction}). Assuming deterministic build processes,
15144 one store file name should map to exactly one build output.
15145 @command{guix challenge} checks whether there is, indeed, a single
15146 mapping by comparing the build outputs of several independent builds of
15147 any given store item.
15149 The command output looks like this:
15153 --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org" \
15154 openssl git pius coreutils grep
15155 updating substitutes from 'https://@value{SUBSTITUTE-SERVER-1}'... 100.0%
15156 updating substitutes from 'https://guix.example.org'... 100.0%
15157 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
15158 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
15159 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
15160 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
15162 /lib/libcrypto.so.1.1
15165 /gnu/store/@dots{}-git-2.5.0 contents differ:
15166 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
15167 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
15168 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
15170 /libexec/git-core/git-fsck
15172 /gnu/store/@dots{}-pius-2.1.1 contents differ:
15173 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
15174 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
15175 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
15177 /share/man/man1/pius.1.gz
15181 5 store items were analyzed:
15182 - 2 (40.0%) were identical
15183 - 3 (60.0%) differed
15184 - 0 (0.0%) were inconclusive
15188 In this example, @command{guix challenge} queries all the substitute
15189 servers for each of the fives packages specified on the command line.
15190 It then reports those store items for which the servers obtained a
15191 result different from the local build (if it exists) and/or different
15192 from one another; here, the @samp{local hash} lines indicate that a
15193 local build result was available for each of these packages and shows
15196 @cindex non-determinism, in package builds
15197 As an example, @code{guix.example.org} always gets a different answer.
15198 Conversely, @code{@value{SUBSTITUTE-SERVER-1}} agrees with local builds, except in the
15199 case of Git. This might indicate that the build process of Git is
15200 non-deterministic, meaning that its output varies as a function of
15201 various things that Guix does not fully control, in spite of building
15202 packages in isolated environments (@pxref{Features}). Most common
15203 sources of non-determinism include the addition of timestamps in build
15204 results, the inclusion of random numbers, and directory listings sorted
15205 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
15208 To find out what is wrong with this Git binary, the easiest approach is
15212 guix challenge git \
15213 --diff=diffoscope \
15214 --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org"
15217 This automatically invokes @command{diffoscope}, which displays detailed
15218 information about files that differ.
15220 Alternatively, we can do something along these lines (@pxref{Invoking guix
15224 $ wget -q -O - https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-git-2.5.0 \
15225 | lzip -d | guix archive -x /tmp/git
15226 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
15229 This command shows the difference between the files resulting from the
15230 local build, and the files resulting from the build on
15231 @code{@value{SUBSTITUTE-SERVER-1}} (@pxref{Overview, Comparing and Merging Files,,
15232 diffutils, Comparing and Merging Files}). The @command{diff} command
15233 works great for text files. When binary files differ, a better option
15234 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
15235 visualize differences for all kinds of files.
15237 Once you have done that work, you can tell whether the differences are due
15238 to a non-deterministic build process or to a malicious server. We try
15239 hard to remove sources of non-determinism in packages to make it easier
15240 to verify substitutes, but of course, this is a process that
15241 involves not just Guix, but a large part of the free software community.
15242 In the meantime, @command{guix challenge} is one tool to help address
15245 If you are writing packages for Guix, you are encouraged to check
15246 whether @code{@value{SUBSTITUTE-SERVER-1}} and other substitute servers obtain the
15247 same build result as you did with:
15250 guix challenge @var{package}
15253 The general syntax is:
15256 guix challenge @var{options} @var{argument}@dots{}
15260 where @var{argument} is a package specification such as
15261 @code{guile@@2.0} or @code{glibc:debug} or, alternatively, a store file
15262 name as returned, for example, by @command{guix build} or @command{guix
15265 When a difference is found between the hash of a locally-built item and
15266 that of a server-provided substitute, or among substitutes provided by
15267 different servers, the command displays it as in the example above and
15268 its exit code is 2 (other non-zero exit codes denote other kinds of
15271 The one option that matters is:
15275 @item --substitute-urls=@var{urls}
15276 Consider @var{urls} the whitespace-separated list of substitute source
15277 URLs to compare to.
15279 @item --diff=@var{mode}
15280 Upon mismatches, show differences according to @var{mode}, one of:
15283 @item @code{simple} (the default)
15284 Show the list of files that differ.
15286 @item @code{diffoscope}
15287 @itemx @var{command}
15288 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
15289 two directories whose contents do not match.
15291 When @var{command} is an absolute file name, run @var{command} instead
15295 Do not show further details about the differences.
15298 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
15299 downloads the store items from the given substitute servers so that it
15304 Show details about matches (identical contents) in addition to
15305 information about mismatches.
15309 @node Invoking guix copy
15310 @section Invoking @command{guix copy}
15312 @cindex copy, of store items, over SSH
15313 @cindex SSH, copy of store items
15314 @cindex sharing store items across machines
15315 @cindex transferring store items across machines
15316 The @command{guix copy} command copies items from the store of one
15317 machine to that of another machine over a secure shell (SSH)
15318 connection@footnote{This command is available only when Guile-SSH was
15319 found. @xref{Requirements}, for details.}. For example, the following
15320 command copies the @code{coreutils} package, the user's profile, and all
15321 their dependencies over to @var{host}, logged in as @var{user}:
15324 guix copy --to=@var{user}@@@var{host} \
15325 coreutils $(readlink -f ~/.guix-profile)
15328 If some of the items to be copied are already present on @var{host},
15329 they are not actually sent.
15331 The command below retrieves @code{libreoffice} and @code{gimp} from
15332 @var{host}, assuming they are available there:
15335 guix copy --from=@var{host} libreoffice gimp
15338 The SSH connection is established using the Guile-SSH client, which is
15339 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
15340 @file{~/.ssh/config}, and uses the SSH agent for authentication.
15342 The key used to sign items that are sent must be accepted by the remote
15343 machine. Likewise, the key used by the remote machine to sign items you
15344 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
15345 own daemon. @xref{Invoking guix archive}, for more information about
15346 store item authentication.
15348 The general syntax is:
15351 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
15354 You must always specify one of the following options:
15357 @item --to=@var{spec}
15358 @itemx --from=@var{spec}
15359 Specify the host to send to or receive from. @var{spec} must be an SSH
15360 spec such as @code{example.org}, @code{charlie@@example.org}, or
15361 @code{charlie@@example.org:2222}.
15364 The @var{items} can be either package names, such as @code{gimp}, or
15365 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
15367 When specifying the name of a package to send, it is first built if
15368 needed, unless @option{--dry-run} was specified. Common build options
15369 are supported (@pxref{Common Build Options}).
15372 @node Invoking guix container
15373 @section Invoking @command{guix container}
15375 @cindex @command{guix container}
15377 As of version @value{VERSION}, this tool is experimental. The interface
15378 is subject to radical change in the future.
15381 The purpose of @command{guix container} is to manipulate processes
15382 running within an isolated environment, commonly known as a
15383 ``container'', typically created by the @command{guix shell}
15384 (@pxref{Invoking guix shell}) and @command{guix system container}
15385 (@pxref{Invoking guix system}) commands.
15387 The general syntax is:
15390 guix container @var{action} @var{options}@dots{}
15393 @var{action} specifies the operation to perform with a container, and
15394 @var{options} specifies the context-specific arguments for the action.
15396 The following actions are available:
15400 Execute a command within the context of a running container.
15405 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
15408 @var{pid} specifies the process ID of the running container.
15409 @var{program} specifies an executable file name within the root file
15410 system of the container. @var{arguments} are the additional options that
15411 will be passed to @var{program}.
15413 The following command launches an interactive login shell inside a
15414 Guix system container, started by @command{guix system container}, and whose
15415 process ID is 9001:
15418 guix container exec 9001 /run/current-system/profile/bin/bash --login
15421 Note that the @var{pid} cannot be the parent process of a container. It
15422 must be PID 1 of the container or one of its child processes.
15426 @node Invoking guix weather
15427 @section Invoking @command{guix weather}
15429 Occasionally you're grumpy because substitutes are lacking and you end
15430 up building packages by yourself (@pxref{Substitutes}). The
15431 @command{guix weather} command reports on substitute availability on the
15432 specified servers so you can have an idea of whether you'll be grumpy
15433 today. It can sometimes be useful info as a user, but it is primarily
15434 useful to people running @command{guix publish} (@pxref{Invoking guix
15437 @cindex statistics, for substitutes
15438 @cindex availability of substitutes
15439 @cindex substitute availability
15440 @cindex weather, substitute availability
15441 Here's a sample run:
15444 $ guix weather --substitute-urls=https://guix.example.org
15445 computing 5,872 package derivations for x86_64-linux...
15446 looking for 6,128 store items on https://guix.example.org..
15447 updating substitutes from 'https://guix.example.org'... 100.0%
15448 https://guix.example.org
15449 43.4% substitutes available (2,658 out of 6,128)
15450 7,032.5 MiB of nars (compressed)
15451 19,824.2 MiB on disk (uncompressed)
15452 0.030 seconds per request (182.9 seconds in total)
15453 33.5 requests per second
15455 9.8% (342 out of 3,470) of the missing items are queued
15457 x86_64-linux: 518 (59.7%)
15458 i686-linux: 221 (25.5%)
15459 aarch64-linux: 128 (14.8%)
15460 build rate: 23.41 builds per hour
15461 x86_64-linux: 11.16 builds per hour
15462 i686-linux: 6.03 builds per hour
15463 aarch64-linux: 6.41 builds per hour
15466 @cindex continuous integration, statistics
15467 As you can see, it reports the fraction of all the packages for which
15468 substitutes are available on the server---regardless of whether
15469 substitutes are enabled, and regardless of whether this server's signing
15470 key is authorized. It also reports the size of the compressed archives
15471 (``nars'') provided by the server, the size the corresponding store
15472 items occupy in the store (assuming deduplication is turned off), and
15473 the server's throughput. The second part gives continuous integration
15474 (CI) statistics, if the server supports it. In addition, using the
15475 @option{--coverage} option, @command{guix weather} can list ``important''
15476 package substitutes missing on the server (see below).
15478 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
15479 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
15480 challenge}, it ignores signatures on those substitutes, which is
15481 innocuous since the command only gathers statistics and cannot install
15484 The general syntax is:
15487 guix weather @var{options}@dots{} [@var{packages}@dots{}]
15490 When @var{packages} is omitted, @command{guix weather} checks the availability
15491 of substitutes for @emph{all} the packages, or for those specified with
15492 @option{--manifest}; otherwise it only considers the specified packages. It
15493 is also possible to query specific system types with @option{--system}.
15494 @command{guix weather} exits with a non-zero code when the fraction of
15495 available substitutes is below 100%.
15497 The available options are listed below.
15500 @item --substitute-urls=@var{urls}
15501 @var{urls} is the space-separated list of substitute server URLs to
15502 query. When this option is omitted, the default set of substitute
15503 servers is queried.
15505 @item --system=@var{system}
15506 @itemx -s @var{system}
15507 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
15508 option can be repeated, in which case @command{guix weather} will query
15509 substitutes for several system types.
15511 @item --manifest=@var{file}
15512 Instead of querying substitutes for all the packages, only ask for those
15513 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
15514 with the @code{-m} option of @command{guix package} (@pxref{Invoking
15517 This option can be repeated several times, in which case the manifests
15520 @item --coverage[=@var{count}]
15521 @itemx -c [@var{count}]
15522 Report on substitute coverage for packages: list packages with at least
15523 @var{count} dependents (zero by default) for which substitutes are
15524 unavailable. Dependent packages themselves are not listed: if @var{b} depends
15525 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
15526 @var{b} usually lacks substitutes as well. The result looks like this:
15529 $ guix weather --substitute-urls=@value{SUBSTITUTE-URLS} -c 10
15530 computing 8,983 package derivations for x86_64-linux...
15531 looking for 9,343 store items on @value{SUBSTITUTE-URLS}...
15532 updating substitutes from '@value{SUBSTITUTE-URLS}'... 100.0%
15533 @value{SUBSTITUTE-URLS}
15534 64.7% substitutes available (6,047 out of 9,343)
15536 2502 packages are missing from '@value{SUBSTITUTE-URLS}' for 'x86_64-linux', among which:
15537 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
15538 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
15539 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
15543 What this example shows is that @code{kcoreaddons} and presumably the 58
15544 packages that depend on it have no substitutes at
15545 @code{@value{SUBSTITUTE-SERVER-1}}; likewise for @code{qgpgme} and the 46
15546 packages that depend on it.
15548 If you are a Guix developer, or if you are taking care of this build farm,
15549 you'll probably want to have a closer look at these packages: they may simply
15552 @item --display-missing
15553 Display the list of store items for which substitutes are missing.
15556 @node Invoking guix processes
15557 @section Invoking @command{guix processes}
15559 The @command{guix processes} command can be useful to developers and system
15560 administrators, especially on multi-user machines and on build farms: it lists
15561 the current sessions (connections to the daemon), as well as information about
15562 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
15563 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
15564 listed.}. Here's an example of the information it returns:
15567 $ sudo guix processes
15570 ClientCommand: guix shell python
15574 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
15578 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
15579 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
15580 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
15581 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
15583 ChildCommand: guix offload x86_64-linux 7200 1 28800
15585 ChildCommand: guix offload x86_64-linux 7200 1 28800
15587 ChildCommand: guix offload x86_64-linux 7200 1 28800
15590 In this example we see that @command{guix-daemon} has three clients:
15591 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
15592 integration tool; their process identifier (PID) is given by the
15593 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
15594 @command{guix-daemon} sub-process of this particular session.
15596 The @code{LockHeld} fields show which store items are currently locked
15597 by this session, which corresponds to store items being built or
15598 substituted (the @code{LockHeld} field is not displayed when
15599 @command{guix processes} is not running as root). Last, by looking at
15600 the @code{ChildPID} and @code{ChildCommand} fields, we understand that
15601 these three builds are being offloaded (@pxref{Daemon Offload Setup}).
15603 The output is in Recutils format so we can use the handy @command{recsel}
15604 command to select sessions of interest (@pxref{Selection Expressions,,,
15605 recutils, GNU recutils manual}). As an example, the command shows the command
15606 line and PID of the client that triggered the build of a Perl package:
15609 $ sudo guix processes | \
15610 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
15612 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
15615 Additional options are listed below.
15618 @item --format=@var{format}
15619 @itemx -f @var{format}
15620 Produce output in the specified @var{format}, one of:
15624 The default option. It outputs a set of Session recutils records
15625 that include each @code{ChildProcess} as a field.
15628 Normalize the output records into record sets (@pxref{Record Sets,,,
15629 recutils, GNU recutils manual}). Normalizing into record sets allows
15630 joins across record types. The example below lists the PID of each
15631 @code{ChildProcess} and the associated PID for @code{Session} that
15632 spawned the @code{ChildProcess} where the @code{Session} was started
15633 using @command{guix build}.
15636 $ guix processes --format=normalized | \
15640 -p Session.PID,PID \
15641 -e 'Session.ClientCommand ~ "guix build"'
15654 @node Foreign Architectures
15655 @chapter Foreign Architectures
15657 You can target computers of different CPU architectures when producing
15658 packages (@pxref{Invoking guix package}), packs (@pxref{Invoking guix
15659 pack}) or full systems (@pxref{Invoking guix system}).
15661 GNU Guix supports two distinct mechanisms to target foreign
15667 @uref{https://en.wikipedia.org/wiki/Cross_compiler,cross-compilation}
15670 The native building mechanism which consists in building using the CPU
15671 instruction set of the foreign system you are targeting. It often
15672 requires emulation, using the QEMU program for instance.
15676 * Cross-Compilation:: Cross-compiling for another architecture.
15677 * Native Builds:: Targeting another architecture through native builds.
15680 @node Cross-Compilation
15681 @section Cross-Compilation
15683 @cindex foreign architectures
15684 The commands supporting cross-compilation are proposing the
15685 @option{--list-targets} and @option{--target} options.
15687 The @option{--list-targets} option lists all the supported targets that
15688 can be passed as an argument to @option{--target}.
15691 $ guix build --list-targets
15692 The available targets are:
15694 - aarch64-linux-gnu
15695 - arm-linux-gnueabihf
15699 - mips64el-linux-gnu
15700 - powerpc-linux-gnu
15701 - powerpc64le-linux-gnu
15702 - riscv64-linux-gnu
15704 - x86_64-w64-mingw32
15707 Targets are specified as GNU triplets (@pxref{Specifying Target
15708 Triplets, GNU configuration triplets,, autoconf, Autoconf}).
15710 Those triplets are passed to GCC and the other underlying compilers
15711 possibly involved when building a package, a system image or any other
15715 $ guix build --target=aarch64-linux-gnu hello
15716 /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12
15718 $ file /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12/bin/hello
15719 /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12/bin/hello: ELF
15720 64-bit LSB executable, ARM aarch64 @dots{}
15723 The major benefit of cross-compilation is that there are no performance
15724 penaly compared to emulation using QEMU. There are however higher risks
15725 that some packages fail to cross-compile because few users are using
15726 this mechanism extensively.
15728 @node Native Builds
15729 @section Native Builds
15731 The commands that support impersonating a specific system have the
15732 @option{--list-systems} and @option{--system} options.
15734 The @option{--list-systems} option lists all the supported systems that
15735 can be passed as an argument to @option{--system}.
15738 $ guix build --list-systems
15739 The available systems are:
15741 - x86_64-linux [current]
15748 - powerpc64le-linux
15751 $ guix build --system=i686-linux hello
15752 /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12
15754 $ file /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12/bin/hello
15755 /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12/bin/hello: ELF
15756 32-bit LSB executable, Intel 80386 @dots{}
15759 In the above example, the current system is @var{x86_64-linux}. The
15760 @var{hello} package is however built for the @var{i686-linux} system.
15762 This is possible because the @var{i686} CPU instruction set is a subset
15763 of the @var{x86_64}, hence @var{i686} targeting binaries can be run on
15766 Still in the context of the previous example, if picking the
15767 @var{aarch64-linux} system and the @command{guix build
15768 --system=aarch64-linux hello} has to build some derivations, an extra
15769 step might be needed.
15771 The @var{aarch64-linux} targeting binaries cannot directly be run on a
15772 @var{x86_64-linux} system. An emulation layer is requested. The GNU
15773 Guix daemon can take advantage of the Linux kernel
15774 @uref{https://en.wikipedia.org/wiki/Binfmt_misc,binfmt_misc} mechanism
15775 for that. In short, the Linux kernel can defer the execution of a
15776 binary targeting a foreign platform, here @var{aarch64-linux}, to a
15777 userspace program, usually an emulator.
15779 There is a service that registers QEMU as a backend for the
15780 @code{binfmt_misc} mechanism (@pxref{Virtualization Services,
15781 @code{qemu-binfmt-service-type}}). On Debian based foreign
15782 distributions, the alternative would be the @code{qemu-user-static}
15785 If the @code{binfmt_misc} mechanism is not setup correctly, the building
15786 will fail this way:
15789 $ guix build --system=armhf-linux hello --check
15791 @ unsupported-platform /gnu/store/jjn969pijv7hff62025yxpfmc8zy0aq0-hello-2.12.drv aarch64-linux
15792 while setting up the build environment: a `aarch64-linux' is required to
15793 build `/gnu/store/jjn969pijv7hff62025yxpfmc8zy0aq0-hello-2.12.drv', but
15794 I am a `x86_64-linux'@dots{}
15797 whereas, with the @code{binfmt_misc} mechanism correctly linked with
15798 QEMU, one can expect to see:
15801 $ guix build --system=armhf-linux hello --check
15802 /gnu/store/13xz4nghg39wpymivlwghy08yzj97hlj-hello-2.12
15805 The main advantage of native building compared to cross-compiling, is
15806 that more packages are likely to build correctly. However it comes at a
15807 price: compilation backed by QEMU is @emph{way slower} than
15808 cross-compilation, because every instruction needs to be emulated.
15810 The availability of substitutes for the architecture targeted by the
15811 @code{--system} option can mitigate this problem. An other way to work
15812 around it is to install GNU Guix on a machine whose CPU supports
15813 the targeted instruction set, and set it up as an offload machine
15814 (@pxref{Daemon Offload Setup}).
15816 @node System Configuration
15817 @chapter System Configuration
15819 @cindex system configuration
15820 Guix System supports a consistent whole-system configuration
15821 mechanism. By that we mean that all aspects of the global system
15822 configuration---such as the available system services, timezone and
15823 locale settings, user accounts---are declared in a single place. Such
15824 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
15826 One of the advantages of putting all the system configuration under the
15827 control of Guix is that it supports transactional system upgrades, and
15828 makes it possible to roll back to a previous system instantiation,
15829 should something go wrong with the new one (@pxref{Features}). Another
15830 advantage is that it makes it easy to replicate the exact same configuration
15831 across different machines, or at different points in time, without
15832 having to resort to additional administration tools layered on top of
15833 the own tools of the system.
15834 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
15836 This section describes this mechanism. First we focus on the system
15837 administrator's viewpoint---explaining how the system is configured and
15838 instantiated. Then we show how this mechanism can be extended, for
15839 instance to support new system services.
15842 * Using the Configuration System:: Customizing your GNU system.
15843 * operating-system Reference:: Detail of operating-system declarations.
15844 * File Systems:: Configuring file system mounts.
15845 * Mapped Devices:: Block device extra processing.
15846 * Swap Space:: Backing RAM with disk space.
15847 * User Accounts:: Specifying user accounts.
15848 * Keyboard Layout:: How the system interprets key strokes.
15849 * Locales:: Language and cultural convention settings.
15850 * Services:: Specifying system services.
15851 * Setuid Programs:: Programs running with elevated privileges.
15852 * X.509 Certificates:: Authenticating HTTPS servers.
15853 * Name Service Switch:: Configuring libc's name service switch.
15854 * Initial RAM Disk:: Linux-Libre bootstrapping.
15855 * Bootloader Configuration:: Configuring the boot loader.
15856 * Invoking guix system:: Instantiating a system configuration.
15857 * Invoking guix deploy:: Deploying a system configuration to a remote host.
15858 * Running Guix in a VM:: How to run Guix System in a virtual machine.
15859 * Defining Services:: Adding new service definitions.
15862 @node Using the Configuration System
15863 @section Using the Configuration System
15865 The operating system is configured by providing an
15866 @code{operating-system} declaration in a file that can then be passed to
15867 the @command{guix system} command (@pxref{Invoking guix system}). A
15868 simple setup, with the default system services, the default Linux-Libre
15869 kernel, initial RAM disk, and boot loader looks like this:
15871 @findex operating-system
15873 @include os-config-bare-bones.texi
15876 This example should be self-describing. Some of the fields defined
15877 above, such as @code{host-name} and @code{bootloader}, are mandatory.
15878 Others, such as @code{packages} and @code{services}, can be omitted, in
15879 which case they get a default value.
15881 Below we discuss the effect of some of the most important fields
15882 (@pxref{operating-system Reference}, for details about all the available
15883 fields), and how to @dfn{instantiate} the operating system using
15884 @command{guix system}.
15886 @unnumberedsubsec Bootloader
15888 @cindex legacy boot, on Intel machines
15889 @cindex BIOS boot, on Intel machines
15892 The @code{bootloader} field describes the method that will be used to boot
15893 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
15894 mode, as in the example above. However, more recent machines rely instead on
15895 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
15896 the @code{bootloader} field should contain something along these lines:
15899 (bootloader-configuration
15900 (bootloader grub-efi-bootloader)
15901 (targets '("/boot/efi")))
15904 @xref{Bootloader Configuration}, for more information on the available
15905 configuration options.
15907 @unnumberedsubsec Globally-Visible Packages
15909 @vindex %base-packages
15910 The @code{packages} field lists packages that will be globally visible
15911 on the system, for all user accounts---i.e., in every user's @env{PATH}
15912 environment variable---in addition to the per-user profiles
15913 (@pxref{Invoking guix package}). The @code{%base-packages} variable
15914 provides all the tools one would expect for basic user and administrator
15915 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
15916 the @command{mg} lightweight text editor, @command{find}, @command{grep},
15917 etc. The example above adds GNU@tie{}Screen to those,
15918 taken from the @code{(gnu packages screen)}
15919 module (@pxref{Package Modules}). The
15920 @code{(list package output)} syntax can be used to add a specific output
15924 (use-modules (gnu packages))
15925 (use-modules (gnu packages dns))
15929 (packages (cons (list isc-bind "utils")
15933 @findex specification->package
15934 Referring to packages by variable name, like @code{isc-bind} above, has
15935 the advantage of being unambiguous; it also allows typos and such to be
15936 diagnosed right away as ``unbound variables''. The downside is that one
15937 needs to know which module defines which package, and to augment the
15938 @code{use-package-modules} line accordingly. To avoid that, one can use
15939 the @code{specification->package} procedure of the @code{(gnu packages)}
15940 module, which returns the best package for a given name or name and
15944 (use-modules (gnu packages))
15948 (packages (append (map specification->package
15949 '("tcpdump" "htop" "gnupg@@2.0"))
15953 @unnumberedsubsec System Services
15956 @vindex %base-services
15957 The @code{services} field lists @dfn{system services} to be made
15958 available when the system starts (@pxref{Services}).
15959 The @code{operating-system} declaration above specifies that, in
15960 addition to the basic services, we want the OpenSSH secure shell
15961 daemon listening on port 2222 (@pxref{Networking Services,
15962 @code{openssh-service-type}}). Under the hood,
15963 @code{openssh-service-type} arranges so that @command{sshd} is started with the
15964 right command-line options, possibly with supporting configuration files
15965 generated as needed (@pxref{Defining Services}).
15967 @cindex customization, of services
15968 @findex modify-services
15969 Occasionally, instead of using the base services as is, you will want to
15970 customize them. To do this, use @code{modify-services} (@pxref{Service
15971 Reference, @code{modify-services}}) to modify the list.
15973 @anchor{auto-login to TTY} For example, suppose you want to modify
15974 @code{guix-daemon} and Mingetty (the console log-in) in the
15975 @code{%base-services} list (@pxref{Base Services,
15976 @code{%base-services}}). To do that, you can write the following in
15977 your operating system declaration:
15980 (define %my-services
15981 ;; My very own list of services.
15982 (modify-services %base-services
15983 (guix-service-type config =>
15984 (guix-configuration
15986 ;; Fetch substitutes from example.org.
15988 (list "https://example.org/guix"
15989 "https://ci.guix.gnu.org"))))
15990 (mingetty-service-type config =>
15991 (mingetty-configuration
15993 ;; Automatically log in as "guest".
15994 (auto-login "guest")))))
15998 (services %my-services))
16001 This changes the configuration---i.e., the service parameters---of the
16002 @code{guix-service-type} instance, and that of all the
16003 @code{mingetty-service-type} instances in the @code{%base-services} list
16004 (@pxref{Auto-Login to a Specific TTY, see the cookbook for how to
16005 auto-login one user to a specific TTY,, guix-cookbook, GNU Guix Cookbook})).
16006 Observe how this is accomplished: first, we arrange for the original
16007 configuration to be bound to the identifier @code{config} in the
16008 @var{body}, and then we write the @var{body} so that it evaluates to the
16009 desired configuration. In particular, notice how we use @code{inherit}
16010 to create a new configuration which has the same values as the old
16011 configuration, but with a few modifications.
16013 @cindex encrypted disk
16014 The configuration for a typical ``desktop'' usage, with an encrypted
16015 root partition, a swap file on the root partition, the X11 display
16016 server, GNOME and Xfce (users can choose which of these desktop
16017 environments to use at the log-in screen by pressing @kbd{F1}), network
16018 management, power management, and more, would look like this:
16021 @include os-config-desktop.texi
16024 A graphical system with a choice of lightweight window managers
16025 instead of full-blown desktop environments would look like this:
16028 @include os-config-lightweight-desktop.texi
16031 This example refers to the @file{/boot/efi} file system by its UUID,
16032 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
16033 as returned by the @command{blkid} command.
16035 @xref{Desktop Services}, for the exact list of services provided by
16036 @code{%desktop-services}. @xref{X.509 Certificates}, for background
16037 information about the @code{nss-certs} package that is used here.
16039 Again, @code{%desktop-services} is just a list of service objects. If
16040 you want to remove services from there, you can do so using the
16041 procedures for list filtering (@pxref{SRFI-1 Filtering and
16042 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
16043 following expression returns a list that contains all the services in
16044 @code{%desktop-services} minus the Avahi service:
16047 (remove (lambda (service)
16048 (eq? (service-kind service) avahi-service-type))
16052 Alternatively, the @code{modify-services} macro can be used:
16055 (modify-services %desktop-services
16056 (delete avahi-service-type))
16060 @unnumberedsubsec Instantiating the System
16062 Assuming the @code{operating-system} declaration
16063 is stored in the @file{my-system-config.scm}
16064 file, the @command{guix system reconfigure my-system-config.scm} command
16065 instantiates that configuration, and makes it the default GRUB boot
16066 entry (@pxref{Invoking guix system}).
16069 We recommend that you keep this @file{my-system-config.scm} file safe
16070 and under version control to easily track changes to your configuration.
16073 The normal way to change the system configuration is by updating this
16074 file and re-running @command{guix system reconfigure}. One should never
16075 have to touch files in @file{/etc} or to run commands that modify the
16076 system state such as @command{useradd} or @command{grub-install}. In
16077 fact, you must avoid that since that would not only void your warranty
16078 but also prevent you from rolling back to previous versions of your
16079 system, should you ever need to.
16081 @cindex roll-back, of the operating system
16082 Speaking of roll-back, each time you run @command{guix system
16083 reconfigure}, a new @dfn{generation} of the system is created---without
16084 modifying or deleting previous generations. Old system generations get
16085 an entry in the bootloader boot menu, allowing you to boot them in case
16086 something went wrong with the latest generation. Reassuring, no? The
16087 @command{guix system list-generations} command lists the system
16088 generations available on disk. It is also possible to roll back the
16089 system via the commands @command{guix system roll-back} and
16090 @command{guix system switch-generation}.
16092 Although the @command{guix system reconfigure} command will not modify
16093 previous generations, you must take care when the current generation is not
16094 the latest (e.g., after invoking @command{guix system roll-back}), since
16095 the operation might overwrite a later generation (@pxref{Invoking guix
16098 @unnumberedsubsec The Programming Interface
16100 At the Scheme level, the bulk of an @code{operating-system} declaration
16101 is instantiated with the following monadic procedure (@pxref{The Store
16104 @deffn {Monadic Procedure} operating-system-derivation os
16105 Return a derivation that builds @var{os}, an @code{operating-system}
16106 object (@pxref{Derivations}).
16108 The output of the derivation is a single directory that refers to all
16109 the packages, configuration files, and other supporting files needed to
16110 instantiate @var{os}.
16113 This procedure is provided by the @code{(gnu system)} module. Along
16114 with @code{(gnu services)} (@pxref{Services}), this module contains the
16115 guts of Guix System. Make sure to visit it!
16118 @node operating-system Reference
16119 @section @code{operating-system} Reference
16121 This section summarizes all the options available in
16122 @code{operating-system} declarations (@pxref{Using the Configuration
16125 @deftp {Data Type} operating-system
16126 This is the data type representing an operating system configuration.
16127 By that, we mean all the global system configuration, not per-user
16128 configuration (@pxref{Using the Configuration System}).
16131 @item @code{kernel} (default: @code{linux-libre})
16132 The package object of the operating system kernel to
16133 use@footnote{Currently only the Linux-libre kernel is fully supported.
16134 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
16135 available when building a virtual machine disk image.}.
16138 @item @code{hurd} (default: @code{#f})
16139 The package object of the Hurd to be started by the kernel. When this
16140 field is set, produce a GNU/Hurd operating system. In that case,
16141 @code{kernel} must also be set to the @code{gnumach} package---the
16142 microkernel the Hurd runs on.
16145 This feature is experimental and only supported for disk images.
16148 @item @code{kernel-loadable-modules} (default: '())
16149 A list of objects (usually packages) to collect loadable kernel modules
16150 from--e.g. @code{(list ddcci-driver-linux)}.
16152 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
16153 List of strings or gexps representing additional arguments to pass on
16154 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
16156 @item @code{bootloader}
16157 The system bootloader configuration object. @xref{Bootloader Configuration}.
16160 This is the label (a string) as it appears in the bootloader's menu entry.
16161 The default label includes the kernel name and version.
16163 @item @code{keyboard-layout} (default: @code{#f})
16164 This field specifies the keyboard layout to use in the console. It can be
16165 either @code{#f}, in which case the default keyboard layout is used (usually
16166 US English), or a @code{<keyboard-layout>} record. @xref{Keyboard Layout},
16167 for more information.
16169 This keyboard layout is in effect as soon as the kernel has booted. For
16170 instance, it is the keyboard layout in effect when you type a passphrase if
16171 your root file system is on a @code{luks-device-mapping} mapped device
16172 (@pxref{Mapped Devices}).
16175 This does @emph{not} specify the keyboard layout used by the bootloader, nor
16176 that used by the graphical display server. @xref{Bootloader Configuration},
16177 for information on how to specify the bootloader's keyboard layout. @xref{X
16178 Window}, for information on how to specify the keyboard layout used by the X
16182 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
16184 @cindex initial RAM disk
16185 The list of Linux kernel modules that need to be available in the
16186 initial RAM disk. @xref{Initial RAM Disk}.
16188 @item @code{initrd} (default: @code{base-initrd})
16189 A procedure that returns an initial RAM disk for the Linux
16190 kernel. This field is provided to support low-level customization and
16191 should rarely be needed for casual use. @xref{Initial RAM Disk}.
16193 @item @code{firmware} (default: @code{%base-firmware})
16195 List of firmware packages loadable by the operating system kernel.
16197 The default includes firmware needed for Atheros- and Broadcom-based
16198 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
16199 respectively). @xref{Hardware Considerations}, for more info on
16200 supported hardware.
16202 @item @code{host-name}
16205 @item @code{hosts-file}
16207 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
16208 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
16209 Reference Manual}). The default is a file with entries for
16210 @code{localhost} and @var{host-name}.
16212 @item @code{mapped-devices} (default: @code{'()})
16213 A list of mapped devices. @xref{Mapped Devices}.
16215 @item @code{file-systems}
16216 A list of file systems. @xref{File Systems}.
16218 @item @code{swap-devices} (default: @code{'()})
16219 @cindex swap devices
16220 A list of swap spaces. @xref{Swap Space}.
16222 @item @code{users} (default: @code{%base-user-accounts})
16223 @itemx @code{groups} (default: @code{%base-groups})
16224 List of user accounts and groups. @xref{User Accounts}.
16226 If the @code{users} list lacks a user account with UID@tie{}0, a
16227 ``root'' account with UID@tie{}0 is automatically added.
16229 @item @code{skeletons} (default: @code{(default-skeletons)})
16230 A list of target file name/file-like object tuples (@pxref{G-Expressions,
16231 file-like objects}). These are the skeleton files that will be added to
16232 the home directory of newly-created user accounts.
16234 For instance, a valid value may look like this:
16237 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
16238 (".guile" ,(plain-file "guile"
16239 "(use-modules (ice-9 readline))
16240 (activate-readline)")))
16243 @item @code{issue} (default: @code{%default-issue})
16244 A string denoting the contents of the @file{/etc/issue} file, which is
16245 displayed when users log in on a text console.
16247 @item @code{packages} (default: @code{%base-packages})
16248 A list of packages to be installed in the global profile, which is accessible
16249 at @file{/run/current-system/profile}. Each element is either a package
16250 variable or a package/output tuple. Here's a simple example of both:
16253 (cons* git ; the default "out" output
16254 (list git "send-email") ; another output of git
16255 %base-packages) ; the default set
16258 The default set includes core utilities and it is good practice to
16259 install non-core utilities in user profiles (@pxref{Invoking guix
16262 @item @code{timezone}
16263 A timezone identifying string---e.g., @code{"Europe/Paris"}.
16265 You can run the @command{tzselect} command to find out which timezone
16266 string corresponds to your region. Choosing an invalid timezone name
16267 causes @command{guix system} to fail.
16269 @item @code{locale} (default: @code{"en_US.utf8"})
16270 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
16271 Library Reference Manual}). @xref{Locales}, for more information.
16273 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
16274 The list of locale definitions to be compiled and that may be used at
16275 run time. @xref{Locales}.
16277 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
16278 The list of GNU@tie{}libc packages whose locale data and tools are used
16279 to build the locale definitions. @xref{Locales}, for compatibility
16280 considerations that justify this option.
16282 @item @code{name-service-switch} (default: @code{%default-nss})
16283 Configuration of the libc name service switch (NSS)---a
16284 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
16287 @item @code{services} (default: @code{%base-services})
16288 A list of service objects denoting system services. @xref{Services}.
16290 @cindex essential services
16291 @item @code{essential-services} (default: ...)
16292 The list of ``essential services''---i.e., things like instances of
16293 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
16294 Reference}), which are derived from the operating system definition itself.
16295 As a user you should @emph{never} need to touch this field.
16297 @item @code{pam-services} (default: @code{(base-pam-services)})
16299 @cindex pluggable authentication modules
16300 Linux @dfn{pluggable authentication module} (PAM) services.
16301 @c FIXME: Add xref to PAM services section.
16303 @item @code{setuid-programs} (default: @code{%setuid-programs})
16304 List of @code{<setuid-program>}. @xref{Setuid Programs}, for more
16307 @item @code{sudoers-file} (default: @code{%sudoers-specification})
16308 @cindex sudoers file
16309 The contents of the @file{/etc/sudoers} file as a file-like object
16310 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
16312 This file specifies which users can use the @command{sudo} command, what
16313 they are allowed to do, and what privileges they may gain. The default
16314 is that only @code{root} and members of the @code{wheel} group may use
16319 @deffn {Scheme Syntax} this-operating-system
16320 When used in the @emph{lexical scope} of an operating system field definition,
16321 this identifier resolves to the operating system being defined.
16323 The example below shows how to refer to the operating system being defined in
16324 the definition of the @code{label} field:
16327 (use-modules (gnu) (guix))
16331 (label (package-full-name
16332 (operating-system-kernel this-operating-system))))
16335 It is an error to refer to @code{this-operating-system} outside an operating
16342 @section File Systems
16344 The list of file systems to be mounted is specified in the
16345 @code{file-systems} field of the operating system declaration
16346 (@pxref{Using the Configuration System}). Each file system is declared
16347 using the @code{file-system} form, like this:
16351 (mount-point "/home")
16352 (device "/dev/sda3")
16356 As usual, some of the fields are mandatory---those shown in the example
16357 above---while others can be omitted. These are described below.
16359 @deftp {Data Type} file-system
16360 Objects of this type represent file systems to be mounted. They
16361 contain the following members:
16365 This is a string specifying the type of the file system---e.g.,
16368 @item @code{mount-point}
16369 This designates the place where the file system is to be mounted.
16371 @item @code{device}
16372 This names the ``source'' of the file system. It can be one of three
16373 things: a file system label, a file system UUID, or the name of a
16374 @file{/dev} node. Labels and UUIDs offer a way to refer to file
16375 systems without having to hard-code their actual device
16376 name@footnote{Note that, while it is tempting to use
16377 @file{/dev/disk/by-uuid} and similar device names to achieve the same
16378 result, this is not recommended: These special device nodes are created
16379 by the udev daemon and may be unavailable at the time the device is
16382 @findex file-system-label
16383 File system labels are created using the @code{file-system-label}
16384 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
16385 plain strings. Here's an example of a file system referred to by its
16386 label, as shown by the @command{e2label} command:
16390 (mount-point "/home")
16392 (device (file-system-label "my-home")))
16396 UUIDs are converted from their string representation (as shown by the
16397 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
16398 @code{uuid} form expects 16-byte UUIDs as defined in
16399 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
16400 form of UUID used by the ext2 family of file systems and others, but it
16401 is different from ``UUIDs'' found in FAT file systems, for instance.},
16406 (mount-point "/home")
16408 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
16411 When the source of a file system is a mapped device (@pxref{Mapped
16412 Devices}), its @code{device} field @emph{must} refer to the mapped
16413 device name---e.g., @file{"/dev/mapper/root-partition"}.
16414 This is required so that
16415 the system knows that mounting the file system depends on having the
16416 corresponding device mapping established.
16418 @item @code{flags} (default: @code{'()})
16419 This is a list of symbols denoting mount flags. Recognized flags
16420 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
16421 access to special files), @code{no-suid} (ignore setuid and setgid
16422 bits), @code{no-atime} (do not update file access times),
16423 @code{strict-atime} (update file access time), @code{lazy-time} (only
16424 update time on the in-memory version of the file inode),
16425 @code{no-exec} (disallow program execution), and @code{shared} (make the
16427 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
16428 Manual}, for more information on these flags.
16430 @item @code{options} (default: @code{#f})
16431 This is either @code{#f}, or a string denoting mount options passed to
16432 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
16433 Library Reference Manual}, for details.
16435 Run @command{man 8 mount} for options for various file systems, but
16436 beware that what it lists as file-system-independent ``mount options'' are
16437 in fact flags, and belong in the @code{flags} field described above.
16439 The @code{file-system-options->alist} and @code{alist->file-system-options}
16440 procedures from @code{(gnu system file-systems)} can be used to convert
16441 file system options given as an association list to the string
16442 representation, and vice-versa.
16444 @item @code{mount?} (default: @code{#t})
16445 This value indicates whether to automatically mount the file system when
16446 the system is brought up. When set to @code{#f}, the file system gets
16447 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
16448 is not automatically mounted.
16450 @item @code{needed-for-boot?} (default: @code{#f})
16451 This Boolean value indicates whether the file system is needed when
16452 booting. If that is true, then the file system is mounted when the
16453 initial RAM disk (initrd) is loaded. This is always the case, for
16454 instance, for the root file system.
16456 @item @code{check?} (default: @code{#t})
16457 This Boolean indicates whether the file system should be checked for
16458 errors before being mounted. How and when this happens can be further
16459 adjusted with the following options.
16461 @item @code{skip-check-if-clean?} (default: @code{#t})
16462 When true, this Boolean indicates that a file system check triggered
16463 by @code{check?} may exit early if the file system is marked as
16464 ``clean'', meaning that it was previously correctly unmounted and
16465 should not contain errors.
16467 Setting this to false will always force a full consistency check when
16468 @code{check?} is true. This may take a very long time and is not
16469 recommended on healthy systems---in fact, it may reduce reliability!
16471 Conversely, some primitive file systems like @code{fat} do not keep
16472 track of clean shutdowns and will perform a full scan regardless of the
16473 value of this option.
16475 @item @code{repair} (default: @code{'preen})
16476 When @code{check?} finds errors, it can (try to) repair them and
16477 continue booting. This option controls when and how to do so.
16479 If false, try not to modify the file system at all. Checking certain
16480 file systems like @code{jfs} may still write to the device to replay
16481 the journal. No repairs will be attempted.
16483 If @code{#t}, try to repair any errors found and assume ``yes'' to
16484 all questions. This will fix the most errors, but may be risky.
16486 If @code{'preen}, repair only errors that are safe to fix without
16487 human interaction. What that means is left up to the developers of
16488 each file system and may be equivalent to ``none'' or ``all''.
16490 @item @code{create-mount-point?} (default: @code{#f})
16491 When true, the mount point is created if it does not exist yet.
16493 @item @code{mount-may-fail?} (default: @code{#f})
16494 When true, this indicates that mounting this file system can fail but
16495 that should not be considered an error. This is useful in unusual
16496 cases; an example of this is @code{efivarfs}, a file system that can
16497 only be mounted on EFI/UEFI systems.
16499 @item @code{dependencies} (default: @code{'()})
16500 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
16501 representing file systems that must be mounted or mapped devices that
16502 must be opened before (and unmounted or closed after) this one.
16504 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
16505 a dependency of @file{/sys/fs/cgroup/cpu} and
16506 @file{/sys/fs/cgroup/memory}.
16508 Another example is a file system that depends on a mapped device, for
16509 example for an encrypted partition (@pxref{Mapped Devices}).
16513 @deffn {Scheme Procedure} file-system-label @var{str}
16514 This procedure returns an opaque file system label from @var{str}, a
16518 (file-system-label "home")
16519 @result{} #<file-system-label "home">
16522 File system labels are used to refer to file systems by label rather
16523 than by device name. See above for examples.
16526 The @code{(gnu system file-systems)} exports the following useful
16529 @defvr {Scheme Variable} %base-file-systems
16530 These are essential file systems that are required on normal systems,
16531 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
16532 below). Operating system declarations should always contain at least
16536 @defvr {Scheme Variable} %pseudo-terminal-file-system
16537 This is the file system to be mounted as @file{/dev/pts}. It supports
16538 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
16539 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
16540 Manual}). Pseudo-terminals are used by terminal emulators such as
16544 @defvr {Scheme Variable} %shared-memory-file-system
16545 This file system is mounted as @file{/dev/shm} and is used to support
16546 memory sharing across processes (@pxref{Memory-mapped I/O,
16547 @code{shm_open},, libc, The GNU C Library Reference Manual}).
16550 @defvr {Scheme Variable} %immutable-store
16551 This file system performs a read-only ``bind mount'' of
16552 @file{/gnu/store}, making it read-only for all the users including
16553 @code{root}. This prevents against accidental modification by software
16554 running as @code{root} or by system administrators.
16556 The daemon itself is still able to write to the store: it remounts it
16557 read-write in its own ``name space.''
16560 @defvr {Scheme Variable} %binary-format-file-system
16561 The @code{binfmt_misc} file system, which allows handling of arbitrary
16562 executable file types to be delegated to user space. This requires the
16563 @code{binfmt.ko} kernel module to be loaded.
16566 @defvr {Scheme Variable} %fuse-control-file-system
16567 The @code{fusectl} file system, which allows unprivileged users to mount
16568 and unmount user-space FUSE file systems. This requires the
16569 @code{fuse.ko} kernel module to be loaded.
16572 The @code{(gnu system uuid)} module provides tools to deal with file
16573 system ``unique identifiers'' (UUIDs).
16575 @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
16576 Return an opaque UUID (unique identifier) object of the given @var{type}
16577 (a symbol) by parsing @var{str} (a string):
16580 (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
16581 @result{} #<<uuid> type: dce bv: @dots{}>
16583 (uuid "1234-ABCD" 'fat)
16584 @result{} #<<uuid> type: fat bv: @dots{}>
16587 @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
16588 @code{ntfs}, or one of the commonly found synonyms for these.
16590 UUIDs are another way to unambiguously refer to file systems in
16591 operating system configuration. See the examples above.
16595 @node Btrfs file system
16596 @subsection Btrfs file system
16598 The Btrfs has special features, such as subvolumes, that merit being
16599 explained in more details. The following section attempts to cover
16600 basic as well as complex uses of a Btrfs file system with the Guix
16603 In its simplest usage, a Btrfs file system can be described, for
16608 (mount-point "/home")
16610 (device (file-system-label "my-home")))
16613 The example below is more complex, as it makes use of a Btrfs
16614 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
16615 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
16616 dependency on @code{mapped-devices}):
16620 (device (file-system-label "my-btrfs-pool"))
16623 (options "subvol=rootfs")
16624 (dependencies mapped-devices))
16627 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
16628 top level during the early boot, and rely on their configuration to
16629 refer to the correct subvolume path within that top level. The
16630 bootloaders operating in this way typically produce their configuration
16631 on a running system where the Btrfs partitions are already mounted and
16632 where the subvolume information is readily available. As an example,
16633 @command{grub-mkconfig}, the configuration generator command shipped
16634 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
16635 path of a subvolume.
16637 The Guix System produces a bootloader configuration using the operating
16638 system configuration as its sole input; it is therefore necessary to
16639 extract the subvolume name on which @file{/gnu/store} lives (if any)
16640 from that operating system configuration. To better illustrate,
16641 consider a subvolume named 'rootfs' which contains the root file system
16642 data. In such situation, the GRUB bootloader would only see the top
16643 level of the root Btrfs partition, e.g.:
16647 ├── rootfs (subvolume directory)
16648 ├── gnu (normal directory)
16649 ├── store (normal directory)
16653 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
16654 of the kernel, initrd binaries and any other files referred to in the
16655 GRUB configuration that must be found during the early boot.
16657 The next example shows a nested hierarchy of subvolumes and
16662 ├── rootfs (subvolume)
16663 ├── gnu (normal directory)
16664 ├── store (subvolume)
16668 This scenario would work without mounting the 'store' subvolume.
16669 Mounting 'rootfs' is sufficient, since the subvolume name matches its
16670 intended mount point in the file system hierarchy. Alternatively, the
16671 'store' subvolume could be referred to by setting the @code{subvol}
16672 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
16674 Finally, a more contrived example of nested subvolumes:
16678 ├── root-snapshots (subvolume)
16679 ├── root-current (subvolume)
16680 ├── guix-store (subvolume)
16684 Here, the 'guix-store' subvolume doesn't match its intended mount point,
16685 so it is necessary to mount it. The subvolume must be fully specified,
16686 by passing its file name to the @code{subvol} option. To illustrate,
16687 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
16688 a file system declaration such as:
16692 (device (file-system-label "btrfs-pool-1"))
16693 (mount-point "/gnu/store")
16695 (options "subvol=root-snapshots/root-current/guix-store,\
16696 compress-force=zstd,space_cache=v2"))
16699 @node Mapped Devices
16700 @section Mapped Devices
16702 @cindex device mapping
16703 @cindex mapped devices
16704 The Linux kernel has a notion of @dfn{device mapping}: a block device,
16705 such as a hard disk partition, can be @dfn{mapped} into another device,
16706 usually in @code{/dev/mapper/},
16707 with additional processing over the data that flows through
16708 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
16709 concept of a ``mapped device'' and that of a file system: both boil down
16710 to @emph{translating} input/output operations made on a file to
16711 operations on its backing store. Thus, the Hurd implements mapped
16712 devices, like file systems, using the generic @dfn{translator} mechanism
16713 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
16714 typical example is encryption device mapping: all writes to the mapped
16715 device are encrypted, and all reads are deciphered, transparently.
16716 Guix extends this notion by considering any device or set of devices that
16717 are @dfn{transformed} in some way to create a new device; for instance,
16718 RAID devices are obtained by @dfn{assembling} several other devices, such
16719 as hard disks or partitions, into a new one that behaves as one partition.
16721 Mapped devices are declared using the @code{mapped-device} form,
16722 defined as follows; for examples, see below.
16724 @deftp {Data Type} mapped-device
16725 Objects of this type represent device mappings that will be made when
16726 the system boots up.
16730 This is either a string specifying the name of the block device to be mapped,
16731 such as @code{"/dev/sda3"}, or a list of such strings when several devices
16732 need to be assembled for creating a new one. In case of LVM this is a
16733 string specifying name of the volume group to be mapped.
16736 This string specifies the name of the resulting mapped device. For
16737 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
16738 specifying @code{"my-partition"} leads to the creation of
16739 the @code{"/dev/mapper/my-partition"} device.
16740 For RAID devices of type @code{raid-device-mapping}, the full device name
16741 such as @code{"/dev/md0"} needs to be given.
16742 LVM logical volumes of type @code{lvm-device-mapping} need to
16743 be specified as @code{"VGNAME-LVNAME"}.
16746 This list of strings specifies names of the resulting mapped devices in case
16747 there are several. The format is identical to @var{target}.
16750 This must be a @code{mapped-device-kind} object, which specifies how
16751 @var{source} is mapped to @var{target}.
16755 @defvr {Scheme Variable} luks-device-mapping
16756 This defines LUKS block device encryption using the @command{cryptsetup}
16757 command from the package with the same name. It relies on the
16758 @code{dm-crypt} Linux kernel module.
16761 @defvr {Scheme Variable} raid-device-mapping
16762 This defines a RAID device, which is assembled using the @code{mdadm}
16763 command from the package with the same name. It requires a Linux kernel
16764 module for the appropriate RAID level to be loaded, such as @code{raid456}
16765 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
16768 @cindex LVM, logical volume manager
16769 @defvr {Scheme Variable} lvm-device-mapping
16770 This defines one or more logical volumes for the Linux
16771 @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
16772 The volume group is activated by the @command{vgchange} command from the
16773 @code{lvm2} package.
16776 @cindex disk encryption
16778 The following example specifies a mapping from @file{/dev/sda3} to
16779 @file{/dev/mapper/home} using LUKS---the
16780 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
16781 standard mechanism for disk encryption.
16782 The @file{/dev/mapper/home}
16783 device can then be used as the @code{device} of a @code{file-system}
16784 declaration (@pxref{File Systems}).
16788 (source "/dev/sda3")
16790 (type luks-device-mapping))
16793 Alternatively, to become independent of device numbering, one may obtain
16794 the LUKS UUID (@dfn{unique identifier}) of the source device by a
16798 cryptsetup luksUUID /dev/sda3
16801 and use it as follows:
16805 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
16807 (type luks-device-mapping))
16810 @cindex swap encryption
16811 It is also desirable to encrypt swap space, since swap space may contain
16812 sensitive data. One way to accomplish that is to use a swap file in a
16813 file system on a device mapped via LUKS encryption. In this way, the
16814 swap file is encrypted because the entire device is encrypted.
16815 @xref{Swap Space}, or @xref{Preparing for Installation,,Disk
16816 Partitioning}, for an example.
16818 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
16819 may be declared as follows:
16823 (source (list "/dev/sda1" "/dev/sdb1"))
16824 (target "/dev/md0")
16825 (type raid-device-mapping))
16828 The @file{/dev/md0} device can then be used as the @code{device} of a
16829 @code{file-system} declaration (@pxref{File Systems}).
16830 Note that the RAID level need not be given; it is chosen during the
16831 initial creation and formatting of the RAID device and is determined
16832 automatically later.
16834 LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
16835 be declared as follows:
16840 (targets (list "vg0-alpha" "vg0-beta"))
16841 (type lvm-device-mapping))
16844 Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
16845 then be used as the @code{device} of a @code{file-system} declaration
16846 (@pxref{File Systems}).
16849 @section Swap Space
16852 Swap space, as it is commonly called, is a disk area specifically
16853 designated for paging: the process in charge of memory management
16854 (the Linux kernel or Hurd's default pager) can decide that some memory
16855 pages stored in RAM which belong to a running program but are unused
16856 should be stored on disk instead. It unloads those from the RAM,
16857 freeing up precious fast memory, and writes them to the swap space. If
16858 the program tries to access that very page, the memory management
16859 process loads it back into memory for the program to use.
16861 A common misconception about swap is that it is only useful when small
16862 amounts of RAM are available to the system. However, it should be noted
16863 that kernels often use all available RAM for disk access caching to make
16864 I/O faster, and thus paging out unused portions of program memory will
16865 expand the RAM available for such caching.
16867 For a more detailed description of how memory is managed from the
16868 viewpoint of a monolithic kernel, @xref{Memory
16869 Concepts,,, libc, The GNU C Library Reference Manual}.
16871 The Linux kernel has support for swap partitions and swap files: the
16872 former uses a whole disk partition for paging, whereas the second uses a
16873 file on a file system for that (the file system driver needs to support
16874 it). On a comparable setup, both have the same performance, so one
16875 should consider ease of use when deciding between them. Partitions are
16876 ``simpler'' and do not need file system support, but need to be
16877 allocated at disk formatting time (logical volumes notwithstanding),
16878 whereas files can be allocated and deallocated at any time.
16880 Note that swap space is not zeroed on shutdown, so sensitive data (such
16881 as passwords) may linger on it if it was paged out. As such, you should
16882 consider having your swap reside on an encrypted device (@pxref{Mapped
16885 @deftp {Data Type} swap-space
16886 Objects of this type represent swap spaces. They contain the following
16890 @item @code{target}
16891 The device or file to use, either a UUID, a @code{file-system-label} or
16892 a string, as in the definition of a @code{file-system} (@pxref{File
16895 @item @code{dependencies} (default: @code{'()})
16896 A list of @code{file-system} or @code{mapped-device} objects, upon which
16897 the availability of the space depends. Note that just like for
16898 @code{file-system} objects, dependencies which are needed for boot and
16899 mounted in early userspace are not managed by the Shepherd, and so
16900 automatically filtered out for you.
16902 @item @code{priority} (default: @code{#f})
16903 Only supported by the Linux kernel. Either @code{#f} to disable swap
16904 priority, or an integer between 0 and 32767. The kernel will first use
16905 swap spaces of higher priority when paging, and use same priority spaces
16906 on a round-robin basis. The kernel will use swap spaces without a set
16907 priority after prioritized spaces, and in the order that they appeared in
16910 @item @code{discard?} (default: @code{#f})
16911 Only supported by the Linux kernel. When true, the kernel will notify
16912 the disk controller of discarded pages, for example with the TRIM
16913 operation on Solid State Drives.
16918 Here are some examples:
16921 (swap-space (target (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
16924 Use the swap partition with the given UUID@. You can learn the UUID of a
16925 Linux swap partition by running @command{swaplabel @var{device}}, where
16926 @var{device} is the @file{/dev} file name of that partition.
16930 (target (file-system-label "swap"))
16931 (dependencies mapped-devices))
16934 Use the partition with label @code{swap}, which can be found after all
16935 the @var{mapped-devices} mapped devices have been opened. Again, the
16936 @command{swaplabel} command allows you to view and change the label of a
16937 Linux swap partition.
16939 Here's a more involved example with the corresponding @code{file-systems} part
16940 of an @code{operating-system} declaration.
16945 (device (file-system-label "root"))
16949 (device (file-system-label "btrfs"))
16950 (mount-point "/btrfs")
16956 (target "/btrfs/swapfile")
16957 (dependencies (filter (file-system-mount-point-predicate "/btrfs")
16961 Use the file @file{/btrfs/swapfile} as swap space, which depends on the
16962 file system mounted at @file{/btrfs}. Note how we use Guile's filter to
16963 select the file system in an elegant fashion!
16965 @node User Accounts
16966 @section User Accounts
16970 @cindex user accounts
16971 User accounts and groups are entirely managed through the
16972 @code{operating-system} declaration. They are specified with the
16973 @code{user-account} and @code{user-group} forms:
16979 (supplementary-groups '("wheel" ;allow use of sudo, etc.
16980 "audio" ;sound card
16981 "video" ;video devices such as webcams
16982 "cdrom")) ;the good ol' CD-ROM
16983 (comment "Bob's sister"))
16986 Here's a user account that uses a different shell and a custom home
16987 directory (the default would be @file{"/home/bob"}):
16993 (comment "Alice's bro")
16994 (shell (file-append zsh "/bin/zsh"))
16995 (home-directory "/home/robert"))
16998 When booting or upon completion of @command{guix system reconfigure},
16999 the system ensures that only the user accounts and groups specified in
17000 the @code{operating-system} declaration exist, and with the specified
17001 properties. Thus, account or group creations or modifications made by
17002 directly invoking commands such as @command{useradd} are lost upon
17003 reconfiguration or reboot. This ensures that the system remains exactly
17006 @deftp {Data Type} user-account
17007 Objects of this type represent user accounts. The following members may
17012 The name of the user account.
17016 This is the name (a string) or identifier (a number) of the user group
17017 this account belongs to.
17019 @item @code{supplementary-groups} (default: @code{'()})
17020 Optionally, this can be defined as a list of group names that this
17021 account belongs to.
17023 @item @code{uid} (default: @code{#f})
17024 This is the user ID for this account (a number), or @code{#f}. In the
17025 latter case, a number is automatically chosen by the system when the
17026 account is created.
17028 @item @code{comment} (default: @code{""})
17029 A comment about the account, such as the account owner's full name.
17031 Note that, for non-system accounts, users are free to change their real
17032 name as it appears in @file{/etc/passwd} using the @command{chfn}
17033 command. When they do, their choice prevails over the system
17034 administrator's choice; reconfiguring does @emph{not} change their name.
17036 @item @code{home-directory}
17037 This is the name of the home directory for the account.
17039 @item @code{create-home-directory?} (default: @code{#t})
17040 Indicates whether the home directory of this account should be created
17041 if it does not exist yet.
17043 @item @code{shell} (default: Bash)
17044 This is a G-expression denoting the file name of a program to be used as
17045 the shell (@pxref{G-Expressions}). For example, you would refer to the
17046 Bash executable like this:
17049 (file-append bash "/bin/bash")
17053 ... and to the Zsh executable like that:
17056 (file-append zsh "/bin/zsh")
17059 @item @code{system?} (default: @code{#f})
17060 This Boolean value indicates whether the account is a ``system''
17061 account. System accounts are sometimes treated specially; for instance,
17062 graphical login managers do not list them.
17064 @anchor{user-account-password}
17065 @cindex password, for user accounts
17066 @item @code{password} (default: @code{#f})
17067 You would normally leave this field to @code{#f}, initialize user
17068 passwords as @code{root} with the @command{passwd} command, and then let
17069 users change it with @command{passwd}. Passwords set with
17070 @command{passwd} are of course preserved across reboot and
17073 If you @emph{do} want to set an initial password for an account, then
17074 this field must contain the encrypted password, as a string. You can use the
17075 @code{crypt} procedure for this purpose:
17082 ;; Specify a SHA-512-hashed initial password.
17083 (password (crypt "InitialPassword!" "$6$abc")))
17087 The hash of this initial password will be available in a file in
17088 @file{/gnu/store}, readable by all the users, so this method must be used with
17092 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
17093 more information on password encryption, and @ref{Encryption,,, guile, GNU
17094 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
17100 User group declarations are even simpler:
17103 (user-group (name "students"))
17106 @deftp {Data Type} user-group
17107 This type is for, well, user groups. There are just a few fields:
17111 The name of the group.
17113 @item @code{id} (default: @code{#f})
17114 The group identifier (a number). If @code{#f}, a new number is
17115 automatically allocated when the group is created.
17117 @item @code{system?} (default: @code{#f})
17118 This Boolean value indicates whether the group is a ``system'' group.
17119 System groups have low numerical IDs.
17121 @item @code{password} (default: @code{#f})
17122 What, user groups can have a password? Well, apparently yes. Unless
17123 @code{#f}, this field specifies the password of the group.
17128 For convenience, a variable lists all the basic user groups one may
17131 @defvr {Scheme Variable} %base-groups
17132 This is the list of basic user groups that users and/or packages expect
17133 to be present on the system. This includes groups such as ``root'',
17134 ``wheel'', and ``users'', as well as groups used to control access to
17135 specific devices such as ``audio'', ``disk'', and ``cdrom''.
17138 @defvr {Scheme Variable} %base-user-accounts
17139 This is the list of basic system accounts that programs may expect to
17140 find on a GNU/Linux system, such as the ``nobody'' account.
17142 Note that the ``root'' account is not included here. It is a
17143 special-case and is automatically added whether or not it is specified.
17146 @node Keyboard Layout
17147 @section Keyboard Layout
17149 @cindex keyboard layout
17151 To specify what each key of your keyboard does, you need to tell the operating
17152 system what @dfn{keyboard layout} you want to use. The default, when nothing
17153 is specified, is the US English QWERTY layout for 105-key PC keyboards.
17154 However, German speakers will usually prefer the German QWERTZ layout, French
17155 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
17156 or bépo, and they might even want to further customize the effect of some of
17157 the keys. This section explains how to get that done.
17159 @cindex keyboard layout, definition
17160 There are three components that will want to know about your keyboard layout:
17164 The @emph{bootloader} may want to know what keyboard layout you want to use
17165 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
17166 you want, for instance, to make sure that you can type the passphrase of your
17167 encrypted root partition using the right layout.
17170 The @emph{operating system kernel}, Linux, will need that so that the console
17171 is properly configured (@pxref{operating-system Reference,
17172 @code{keyboard-layout}}).
17175 The @emph{graphical display server}, usually Xorg, also has its own idea of
17176 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
17179 Guix allows you to configure all three separately but, fortunately, it allows
17180 you to share the same keyboard layout for all three components.
17182 @cindex XKB, keyboard layouts
17183 Keyboard layouts are represented by records created by the
17184 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
17185 the X Keyboard extension (XKB), each layout has four attributes: a name (often
17186 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
17187 optional variant name, an optional keyboard model name, and a possibly empty
17188 list of additional options. In most cases the layout name is all you care
17191 @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
17192 [#:model] [#:options '()]
17193 Return a new keyboard layout with the given @var{name} and @var{variant}.
17195 @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
17196 string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
17197 @code{xkeyboard-config} package for valid options.
17200 Here are a few examples:
17203 ;; The German QWERTZ layout. Here we assume a standard
17204 ;; "pc105" keyboard model.
17205 (keyboard-layout "de")
17207 ;; The bépo variant of the French layout.
17208 (keyboard-layout "fr" "bepo")
17210 ;; The Catalan layout.
17211 (keyboard-layout "es" "cat")
17213 ;; Arabic layout with "Alt-Shift" to switch to US layout.
17214 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
17216 ;; The Latin American Spanish layout. In addition, the
17217 ;; "Caps Lock" key is used as an additional "Ctrl" key,
17218 ;; and the "Menu" key is used as a "Compose" key to enter
17219 ;; accented letters.
17220 (keyboard-layout "latam"
17221 #:options '("ctrl:nocaps" "compose:menu"))
17223 ;; The Russian layout for a ThinkPad keyboard.
17224 (keyboard-layout "ru" #:model "thinkpad")
17226 ;; The "US international" layout, which is the US layout plus
17227 ;; dead keys to enter accented characters. This is for an
17228 ;; Apple MacBook keyboard.
17229 (keyboard-layout "us" "intl" #:model "macbook78")
17232 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
17233 for a complete list of supported layouts, variants, and models.
17235 @cindex keyboard layout, configuration
17236 Let's say you want your system to use the Turkish keyboard layout throughout
17237 your system---bootloader, console, and Xorg. Here's what your system
17238 configuration would look like:
17240 @findex set-xorg-configuration
17242 ;; Using the Turkish layout for the bootloader, the console,
17247 (keyboard-layout (keyboard-layout "tr")) ;for the console
17248 (bootloader (bootloader-configuration
17249 (bootloader grub-efi-bootloader)
17250 (targets '("/boot/efi"))
17251 (keyboard-layout keyboard-layout))) ;for GRUB
17252 (services (cons (set-xorg-configuration
17253 (xorg-configuration ;for Xorg
17254 (keyboard-layout keyboard-layout)))
17255 %desktop-services)))
17258 In the example above, for GRUB and for Xorg, we just refer to the
17259 @code{keyboard-layout} field defined above, but we could just as well refer to
17260 a different layout. The @code{set-xorg-configuration} procedure communicates
17261 the desired Xorg configuration to the graphical log-in manager, by default
17264 We've discussed how to specify the @emph{default} keyboard layout of your
17265 system when it starts, but you can also adjust it at run time:
17269 If you're using GNOME, its settings panel has a ``Region & Language'' entry
17270 where you can select one or more keyboard layouts.
17273 Under Xorg, the @command{setxkbmap} command (from the same-named package)
17274 allows you to change the current layout. For example, this is how you would
17275 change the layout to US Dvorak:
17278 setxkbmap us dvorak
17282 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
17283 console. However, note that @code{loadkeys} does @emph{not} use the XKB
17284 keyboard layout categorization described above. The command below loads the
17285 French bépo layout:
17296 A @dfn{locale} defines cultural conventions for a particular language
17297 and region of the world (@pxref{Locales,,, libc, The GNU C Library
17298 Reference Manual}). Each locale has a name that typically has the form
17299 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
17300 @code{fr_LU.utf8} designates the locale for the French language, with
17301 cultural conventions from Luxembourg, and using the UTF-8 encoding.
17303 @cindex locale definition
17304 Usually, you will want to specify the default locale for the machine
17305 using the @code{locale} field of the @code{operating-system} declaration
17306 (@pxref{operating-system Reference, @code{locale}}).
17308 The selected locale is automatically added to the @dfn{locale
17309 definitions} known to the system if needed, with its codeset inferred
17310 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
17311 @code{UTF-8} codeset. Additional locale definitions can be specified in
17312 the @code{locale-definitions} slot of @code{operating-system}---this is
17313 useful, for instance, if the codeset could not be inferred from the
17314 locale name. The default set of locale definitions includes some widely
17315 used locales, but not all the available locales, in order to save space.
17317 For instance, to add the North Frisian locale for Germany, the value of
17321 (cons (locale-definition
17322 (name "fy_DE.utf8") (source "fy_DE"))
17323 %default-locale-definitions)
17326 Likewise, to save space, one might want @code{locale-definitions} to
17327 list only the locales that are actually used, as in:
17330 (list (locale-definition
17331 (name "ja_JP.eucjp") (source "ja_JP")
17332 (charset "EUC-JP")))
17336 The compiled locale definitions are available at
17337 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
17338 version, which is the default location where the GNU@tie{}libc provided
17339 by Guix looks for locale data. This can be overridden using the
17340 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
17341 @env{LOCPATH} and locale packages}).
17343 The @code{locale-definition} form is provided by the @code{(gnu system
17344 locale)} module. Details are given below.
17346 @deftp {Data Type} locale-definition
17347 This is the data type of a locale definition.
17352 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
17353 Reference Manual}, for more information on locale names.
17355 @item @code{source}
17356 The name of the source for that locale. This is typically the
17357 @code{@var{language}_@var{territory}} part of the locale name.
17359 @item @code{charset} (default: @code{"UTF-8"})
17360 The ``character set'' or ``code set'' for that locale,
17361 @uref{https://www.iana.org/assignments/character-sets, as defined by
17367 @defvr {Scheme Variable} %default-locale-definitions
17368 A list of commonly used UTF-8 locales, used as the default
17369 value of the @code{locale-definitions} field of @code{operating-system}
17372 @cindex locale name
17373 @cindex normalized codeset in locale names
17374 These locale definitions use the @dfn{normalized codeset} for the part
17375 that follows the dot in the name (@pxref{Using gettextized software,
17376 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
17377 instance it has @code{uk_UA.utf8} but @emph{not}, say,
17378 @code{uk_UA.UTF-8}.
17381 @subsection Locale Data Compatibility Considerations
17383 @cindex incompatibility, of locale data
17384 @code{operating-system} declarations provide a @code{locale-libcs} field
17385 to specify the GNU@tie{}libc packages that are used to compile locale
17386 declarations (@pxref{operating-system Reference}). ``Why would I
17387 care?'', you may ask. Well, it turns out that the binary format of
17388 locale data is occasionally incompatible from one libc version to
17391 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
17392 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
17393 For instance, a program linked against libc version 2.21 is unable to
17394 read locale data produced with libc 2.22; worse, that program
17395 @emph{aborts} instead of simply ignoring the incompatible locale
17396 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
17397 the incompatible locale data, which is already an improvement.}.
17398 Similarly, a program linked against libc 2.22 can read most, but not
17399 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
17400 data is incompatible); thus calls to @code{setlocale} may fail, but
17401 programs will not abort.
17403 The ``problem'' with Guix is that users have a lot of freedom: They can
17404 choose whether and when to upgrade software in their profiles, and might
17405 be using a libc version different from the one the system administrator
17406 used to build the system-wide locale data.
17408 Fortunately, unprivileged users can also install their own locale data
17409 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
17410 @env{GUIX_LOCPATH} and locale packages}).
17412 Still, it is best if the system-wide locale data at
17413 @file{/run/current-system/locale} is built for all the libc versions
17414 actually in use on the system, so that all the programs can access
17415 it---this is especially crucial on a multi-user system. To do that, the
17416 administrator can specify several libc packages in the
17417 @code{locale-libcs} field of @code{operating-system}:
17420 (use-package-modules base)
17424 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
17427 This example would lead to a system containing locale definitions for
17428 both libc 2.21 and the current version of libc in
17429 @file{/run/current-system/locale}.
17435 @cindex system services
17436 An important part of preparing an @code{operating-system} declaration is
17437 listing @dfn{system services} and their configuration (@pxref{Using the
17438 Configuration System}). System services are typically daemons launched
17439 when the system boots, or other actions needed at that time---e.g.,
17440 configuring network access.
17442 Guix has a broad definition of ``service'' (@pxref{Service
17443 Composition}), but many services are managed by the GNU@tie{}Shepherd
17444 (@pxref{Shepherd Services}). On a running system, the @command{herd}
17445 command allows you to list the available services, show their status,
17446 start and stop them, or do other specific operations (@pxref{Jump
17447 Start,,, shepherd, The GNU Shepherd Manual}). For example:
17453 The above command, run as @code{root}, lists the currently defined
17454 services. The @command{herd doc} command shows a synopsis of the given
17455 service and its associated actions:
17459 Run libc's name service cache daemon (nscd).
17461 # herd doc nscd action invalidate
17462 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
17465 The @command{start}, @command{stop}, and @command{restart} sub-commands
17466 have the effect you would expect. For instance, the commands below stop
17467 the nscd service and restart the Xorg display server:
17471 Service nscd has been stopped.
17472 # herd restart xorg-server
17473 Service xorg-server has been stopped.
17474 Service xorg-server has been started.
17477 The following sections document the available services, starting with
17478 the core services, that may be used in an @code{operating-system}
17482 * Base Services:: Essential system services.
17483 * Scheduled Job Execution:: The mcron service.
17484 * Log Rotation:: The rottlog service.
17485 * Networking Setup:: Setting up network interfaces.
17486 * Networking Services:: Firewall, SSH daemon, etc.
17487 * Unattended Upgrades:: Automated system upgrades.
17488 * X Window:: Graphical display.
17489 * Printing Services:: Local and remote printer support.
17490 * Desktop Services:: D-Bus and desktop services.
17491 * Sound Services:: ALSA and Pulseaudio services.
17492 * Database Services:: SQL databases, key-value stores, etc.
17493 * Mail Services:: IMAP, POP3, SMTP, and all that.
17494 * Messaging Services:: Messaging services.
17495 * Telephony Services:: Telephony services.
17496 * File-Sharing Services:: File-sharing services.
17497 * Monitoring Services:: Monitoring services.
17498 * Kerberos Services:: Kerberos services.
17499 * LDAP Services:: LDAP services.
17500 * Web Services:: Web servers.
17501 * Certificate Services:: TLS certificates via Let's Encrypt.
17502 * DNS Services:: DNS daemons.
17503 * VPN Services:: VPN daemons.
17504 * Network File System:: NFS related services.
17505 * Continuous Integration:: Cuirass and Laminar services.
17506 * Power Management Services:: Extending battery life.
17507 * Audio Services:: The MPD.
17508 * Virtualization Services:: Virtualization services.
17509 * Version Control Services:: Providing remote access to Git repositories.
17510 * Game Services:: Game servers.
17511 * PAM Mount Service:: Service to mount volumes when logging in.
17512 * Guix Services:: Services relating specifically to Guix.
17513 * Linux Services:: Services tied to the Linux kernel.
17514 * Hurd Services:: Services specific for a Hurd System.
17515 * Miscellaneous Services:: Other services.
17518 @node Base Services
17519 @subsection Base Services
17521 The @code{(gnu services base)} module provides definitions for the basic
17522 services that one expects from the system. The services exported by
17523 this module are listed below.
17525 @defvr {Scheme Variable} %base-services
17526 This variable contains a list of basic services (@pxref{Service Types
17527 and Services}, for more information on service objects) one would
17528 expect from the system: a login service (mingetty) on each tty, syslogd,
17529 the libc name service cache daemon (nscd), the udev device manager, and
17532 This is the default value of the @code{services} field of
17533 @code{operating-system} declarations. Usually, when customizing a
17534 system, you will want to append services to @code{%base-services}, like
17538 (append (list (service avahi-service-type)
17539 (service openssh-service-type))
17544 @defvr {Scheme Variable} special-files-service-type
17545 This is the service that sets up ``special files'' such as
17546 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
17548 The value associated with @code{special-files-service-type} services
17549 must be a list of tuples where the first element is the ``special file''
17550 and the second element is its target. By default it is:
17552 @cindex @file{/bin/sh}
17553 @cindex @file{sh}, in @file{/bin}
17555 `(("/bin/sh" ,(file-append bash "/bin/sh")))
17558 @cindex @file{/usr/bin/env}
17559 @cindex @file{env}, in @file{/usr/bin}
17560 If you want to add, say, @code{/usr/bin/env} to your system, you can
17564 `(("/bin/sh" ,(file-append bash "/bin/sh"))
17565 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
17568 Since this is part of @code{%base-services}, you can use
17569 @code{modify-services} to customize the set of special files
17570 (@pxref{Service Reference, @code{modify-services}}). But the simple way
17571 to add a special file is @i{via} the @code{extra-special-file} procedure
17575 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
17576 Use @var{target} as the ``special file'' @var{file}.
17578 For example, adding the following lines to the @code{services} field of
17579 your operating system declaration leads to a @file{/usr/bin/env}
17583 (extra-special-file "/usr/bin/env"
17584 (file-append coreutils "/bin/env"))
17588 @deffn {Scheme Procedure} host-name-service @var{name}
17589 Return a service that sets the host name to @var{name}.
17592 @defvr {Scheme Variable} console-font-service-type
17593 Install the given fonts on the specified ttys (fonts are per
17594 virtual console on the kernel Linux). The value of this service is a list of
17595 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
17596 package or any valid argument to @command{setfont}, as in this example:
17599 `(("tty1" . "LatGrkCyr-8x16")
17600 ("tty2" . ,(file-append
17602 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
17603 ("tty3" . ,(file-append
17605 "/share/consolefonts/ter-132n"))) ; for HDPI
17609 @deffn {Scheme Procedure} login-service @var{config}
17610 Return a service to run login according to @var{config}, a
17611 @code{<login-configuration>} object, which specifies the message of the day,
17612 among other things.
17615 @deftp {Data Type} login-configuration
17616 This is the data type representing the configuration of login.
17621 @cindex message of the day
17622 A file-like object containing the ``message of the day''.
17624 @item @code{allow-empty-passwords?} (default: @code{#t})
17625 Allow empty passwords by default so that first-time users can log in when
17626 the 'root' account has just been created.
17631 @deffn {Scheme Procedure} mingetty-service @var{config}
17632 Return a service to run mingetty according to @var{config}, a
17633 @code{<mingetty-configuration>} object, which specifies the tty to run, among
17637 @deftp {Data Type} mingetty-configuration
17638 This is the data type representing the configuration of Mingetty, which
17639 provides the default implementation of virtual console log-in.
17644 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
17646 @item @code{auto-login} (default: @code{#f})
17647 When true, this field must be a string denoting the user name under
17648 which the system automatically logs in. When it is @code{#f}, a
17649 user name and password must be entered to log in.
17651 @item @code{login-program} (default: @code{#f})
17652 This must be either @code{#f}, in which case the default log-in program
17653 is used (@command{login} from the Shadow tool suite), or a gexp denoting
17654 the name of the log-in program.
17656 @item @code{login-pause?} (default: @code{#f})
17657 When set to @code{#t} in conjunction with @var{auto-login}, the user
17658 will have to press a key before the log-in shell is launched.
17660 @item @code{clear-on-logout?} (default: @code{#t})
17661 When set to @code{#t}, the screen will be cleared after logout.
17663 @item @code{mingetty} (default: @var{mingetty})
17664 The Mingetty package to use.
17669 @deffn {Scheme Procedure} agetty-service @var{config}
17670 Return a service to run agetty according to @var{config}, an
17671 @code{<agetty-configuration>} object, which specifies the tty to run,
17672 among other things.
17675 @deftp {Data Type} agetty-configuration
17676 This is the data type representing the configuration of agetty, which
17677 implements virtual and serial console log-in. See the @code{agetty(8)}
17678 man page for more information.
17683 The name of the console this agetty runs on, as a string---e.g.,
17684 @code{"ttyS0"}. This argument is optional, it will default to
17685 a reasonable default serial port used by the kernel Linux.
17687 For this, if there is a value for an option @code{agetty.tty} in the kernel
17688 command line, agetty will extract the device name of the serial port
17689 from it and use that.
17691 If not and if there is a value for an option @code{console} with a tty in
17692 the Linux command line, agetty will extract the device name of the
17693 serial port from it and use that.
17695 In both cases, agetty will leave the other serial device settings
17696 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
17699 @item @code{baud-rate} (default: @code{#f})
17700 A string containing a comma-separated list of one or more baud rates, in
17703 @item @code{term} (default: @code{#f})
17704 A string containing the value used for the @env{TERM} environment
17707 @item @code{eight-bits?} (default: @code{#f})
17708 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
17711 @item @code{auto-login} (default: @code{#f})
17712 When passed a login name, as a string, the specified user will be logged
17713 in automatically without prompting for their login name or password.
17715 @item @code{no-reset?} (default: @code{#f})
17716 When @code{#t}, don't reset terminal cflags (control modes).
17718 @item @code{host} (default: @code{#f})
17719 This accepts a string containing the ``login_host'', which will be written
17720 into the @file{/var/run/utmpx} file.
17722 @item @code{remote?} (default: @code{#f})
17723 When set to @code{#t} in conjunction with @var{host}, this will add an
17724 @code{-r} fakehost option to the command line of the login program
17725 specified in @var{login-program}.
17727 @item @code{flow-control?} (default: @code{#f})
17728 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
17730 @item @code{no-issue?} (default: @code{#f})
17731 When set to @code{#t}, the contents of the @file{/etc/issue} file will
17732 not be displayed before presenting the login prompt.
17734 @item @code{init-string} (default: @code{#f})
17735 This accepts a string that will be sent to the tty or modem before
17736 sending anything else. It can be used to initialize a modem.
17738 @item @code{no-clear?} (default: @code{#f})
17739 When set to @code{#t}, agetty will not clear the screen before showing
17742 @item @code{login-program} (default: (file-append shadow "/bin/login"))
17743 This must be either a gexp denoting the name of a log-in program, or
17744 unset, in which case the default value is the @command{login} from the
17747 @item @code{local-line} (default: @code{#f})
17748 Control the CLOCAL line flag. This accepts one of three symbols as
17749 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
17750 the default value chosen by agetty is @code{'auto}.
17752 @item @code{extract-baud?} (default: @code{#f})
17753 When set to @code{#t}, instruct agetty to try to extract the baud rate
17754 from the status messages produced by certain types of modems.
17756 @item @code{skip-login?} (default: @code{#f})
17757 When set to @code{#t}, do not prompt the user for a login name. This
17758 can be used with @var{login-program} field to use non-standard login
17761 @item @code{no-newline?} (default: @code{#f})
17762 When set to @code{#t}, do not print a newline before printing the
17763 @file{/etc/issue} file.
17765 @c Is this dangerous only when used with login-program, or always?
17766 @item @code{login-options} (default: @code{#f})
17767 This option accepts a string containing options that are passed to the
17768 login program. When used with the @var{login-program}, be aware that a
17769 malicious user could try to enter a login name containing embedded
17770 options that could be parsed by the login program.
17772 @item @code{login-pause} (default: @code{#f})
17773 When set to @code{#t}, wait for any key before showing the login prompt.
17774 This can be used in conjunction with @var{auto-login} to save memory by
17775 lazily spawning shells.
17777 @item @code{chroot} (default: @code{#f})
17778 Change root to the specified directory. This option accepts a directory
17781 @item @code{hangup?} (default: @code{#f})
17782 Use the Linux system call @code{vhangup} to do a virtual hangup of the
17783 specified terminal.
17785 @item @code{keep-baud?} (default: @code{#f})
17786 When set to @code{#t}, try to keep the existing baud rate. The baud
17787 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
17790 @item @code{timeout} (default: @code{#f})
17791 When set to an integer value, terminate if no user name could be read
17792 within @var{timeout} seconds.
17794 @item @code{detect-case?} (default: @code{#f})
17795 When set to @code{#t}, turn on support for detecting an uppercase-only
17796 terminal. This setting will detect a login name containing only
17797 uppercase letters as indicating an uppercase-only terminal and turn on
17798 some upper-to-lower case conversions. Note that this will not support
17799 Unicode characters.
17801 @item @code{wait-cr?} (default: @code{#f})
17802 When set to @code{#t}, wait for the user or modem to send a
17803 carriage-return or linefeed character before displaying
17804 @file{/etc/issue} or login prompt. This is typically used with the
17805 @var{init-string} option.
17807 @item @code{no-hints?} (default: @code{#f})
17808 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
17811 @item @code{no-hostname?} (default: @code{#f})
17812 By default, the hostname is printed. When this option is set to
17813 @code{#t}, no hostname will be shown at all.
17815 @item @code{long-hostname?} (default: @code{#f})
17816 By default, the hostname is only printed until the first dot. When this
17817 option is set to @code{#t}, the fully qualified hostname by
17818 @code{gethostname} or @code{getaddrinfo} is shown.
17820 @item @code{erase-characters} (default: @code{#f})
17821 This option accepts a string of additional characters that should be
17822 interpreted as backspace when the user types their login name.
17824 @item @code{kill-characters} (default: @code{#f})
17825 This option accepts a string that should be interpreted to mean ``ignore
17826 all previous characters'' (also called a ``kill'' character) when the user
17827 types their login name.
17829 @item @code{chdir} (default: @code{#f})
17830 This option accepts, as a string, a directory path that will be changed
17833 @item @code{delay} (default: @code{#f})
17834 This options accepts, as an integer, the number of seconds to sleep
17835 before opening the tty and displaying the login prompt.
17837 @item @code{nice} (default: @code{#f})
17838 This option accepts, as an integer, the nice value with which to run the
17839 @command{login} program.
17841 @item @code{extra-options} (default: @code{'()})
17842 This option provides an ``escape hatch'' for the user to provide arbitrary
17843 command-line arguments to @command{agetty} as a list of strings.
17845 @item @code{shepherd-requirement} (default: @code{'()})
17846 The option can be used to provides extra shepherd requirements (for example
17847 @code{'syslogd}) to the respective @code{'term-}* shepherd service.
17852 @deffn {Scheme Procedure} kmscon-service-type @var{config}
17853 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
17854 according to @var{config}, a @code{<kmscon-configuration>} object, which
17855 specifies the tty to run, among other things.
17858 @deftp {Data Type} kmscon-configuration
17859 This is the data type representing the configuration of Kmscon, which
17860 implements virtual console log-in.
17864 @item @code{virtual-terminal}
17865 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
17867 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
17868 A gexp denoting the name of the log-in program. The default log-in program is
17869 @command{login} from the Shadow tool suite.
17871 @item @code{login-arguments} (default: @code{'("-p")})
17872 A list of arguments to pass to @command{login}.
17874 @item @code{auto-login} (default: @code{#f})
17875 When passed a login name, as a string, the specified user will be logged
17876 in automatically without prompting for their login name or password.
17878 @item @code{hardware-acceleration?} (default: #f)
17879 Whether to use hardware acceleration.
17881 @item @code{font-engine} (default: @code{"pango"})
17882 Font engine used in Kmscon.
17884 @item @code{font-size} (default: @code{12})
17885 Font size used in Kmscon.
17887 @item @code{keyboard-layout} (default: @code{#f})
17888 If this is @code{#f}, Kmscon uses the default keyboard layout---usually US
17889 English (``qwerty'') for a 105-key PC keyboard.
17891 Otherwise this must be a @code{keyboard-layout} object specifying the
17892 keyboard layout. @xref{Keyboard Layout}, for more information on how to
17893 specify the keyboard layout.
17895 @item @code{kmscon} (default: @var{kmscon})
17896 The Kmscon package to use.
17901 @cindex name service cache daemon
17903 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
17904 [#:name-services '()]
17905 Return a service that runs the libc name service cache daemon (nscd) with the
17906 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
17907 Service Switch}, for an example.
17909 For convenience, the Shepherd service for nscd provides the following actions:
17913 @cindex cache invalidation, nscd
17914 @cindex nscd, cache invalidation
17915 This invalidate the given cache. For instance, running:
17918 herd invalidate nscd hosts
17922 invalidates the host name lookup cache of nscd.
17925 Running @command{herd statistics nscd} displays information about nscd usage
17931 @defvr {Scheme Variable} %nscd-default-configuration
17932 This is the default @code{<nscd-configuration>} value (see below) used
17933 by @code{nscd-service}. It uses the caches defined by
17934 @code{%nscd-default-caches}; see below.
17937 @deftp {Data Type} nscd-configuration
17938 This is the data type representing the name service cache daemon (nscd)
17943 @item @code{name-services} (default: @code{'()})
17944 List of packages denoting @dfn{name services} that must be visible to
17945 the nscd---e.g., @code{(list @var{nss-mdns})}.
17947 @item @code{glibc} (default: @var{glibc})
17948 Package object denoting the GNU C Library providing the @command{nscd}
17951 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
17952 Name of the nscd log file. This is where debugging output goes when
17953 @code{debug-level} is strictly positive.
17955 @item @code{debug-level} (default: @code{0})
17956 Integer denoting the debugging levels. Higher numbers mean that more
17957 debugging output is logged.
17959 @item @code{caches} (default: @code{%nscd-default-caches})
17960 List of @code{<nscd-cache>} objects denoting things to be cached; see
17966 @deftp {Data Type} nscd-cache
17967 Data type representing a cache database of nscd and its parameters.
17971 @item @code{database}
17972 This is a symbol representing the name of the database to be cached.
17973 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
17974 @code{services}, which designate the corresponding NSS database
17975 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
17977 @item @code{positive-time-to-live}
17978 @itemx @code{negative-time-to-live} (default: @code{20})
17979 A number representing the number of seconds during which a positive or
17980 negative lookup result remains in cache.
17982 @item @code{check-files?} (default: @code{#t})
17983 Whether to check for updates of the files corresponding to
17986 For instance, when @var{database} is @code{hosts}, setting this flag
17987 instructs nscd to check for updates in @file{/etc/hosts} and to take
17990 @item @code{persistent?} (default: @code{#t})
17991 Whether the cache should be stored persistently on disk.
17993 @item @code{shared?} (default: @code{#t})
17994 Whether the cache should be shared among users.
17996 @item @code{max-database-size} (default: 32@tie{}MiB)
17997 Maximum size in bytes of the database cache.
17999 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
18000 @c settings, so leave them out.
18005 @defvr {Scheme Variable} %nscd-default-caches
18006 List of @code{<nscd-cache>} objects used by default by
18007 @code{nscd-configuration} (see above).
18009 It enables persistent and aggressive caching of service and host name
18010 lookups. The latter provides better host name lookup performance,
18011 resilience in the face of unreliable name servers, and also better
18012 privacy---often the result of host name lookups is in local cache, so
18013 external name servers do not even need to be queried.
18016 @anchor{syslog-configuration-type}
18019 @deftp {Data Type} syslog-configuration
18020 This data type represents the configuration of the syslog daemon.
18023 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
18024 The syslog daemon to use.
18026 @item @code{config-file} (default: @code{%default-syslog.conf})
18027 The syslog configuration file to use.
18032 @anchor{syslog-service}
18034 @deffn {Scheme Procedure} syslog-service @var{config}
18035 Return a service that runs a syslog daemon according to @var{config}.
18037 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
18038 information on the configuration file syntax.
18041 @defvr {Scheme Variable} guix-service-type
18042 This is the type of the service that runs the build daemon,
18043 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
18044 @code{guix-configuration} record as described below.
18047 @anchor{guix-configuration-type}
18048 @deftp {Data Type} guix-configuration
18049 This data type represents the configuration of the Guix build daemon.
18050 @xref{Invoking guix-daemon}, for more information.
18053 @item @code{guix} (default: @var{guix})
18054 The Guix package to use.
18056 @item @code{build-group} (default: @code{"guixbuild"})
18057 Name of the group for build user accounts.
18059 @item @code{build-accounts} (default: @code{10})
18060 Number of build user accounts to create.
18062 @item @code{authorize-key?} (default: @code{#t})
18063 @cindex substitutes, authorization thereof
18064 Whether to authorize the substitute keys listed in
18065 @code{authorized-keys}---by default that of
18066 @code{@value{SUBSTITUTE-SERVER-1}} and
18067 @code{@value{SUBSTITUTE-SERVER-2}}
18068 (@pxref{Substitutes}).
18070 When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
18071 changed by invoking @command{guix archive --authorize}. You must
18072 instead adjust @code{guix-configuration} as you wish and reconfigure the
18073 system. This ensures that your operating system configuration file is
18077 When booting or reconfiguring to a system where @code{authorize-key?}
18078 is true, the existing @file{/etc/guix/acl} file is backed up as
18079 @file{/etc/guix/acl.bak} if it was determined to be a manually modified
18080 file. This is to facilitate migration from earlier versions, which
18081 allowed for in-place modifications to @file{/etc/guix/acl}.
18084 @vindex %default-authorized-guix-keys
18085 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
18086 The list of authorized key files for archive imports, as a list of
18087 string-valued gexps (@pxref{Invoking guix archive}). By default, it
18088 contains that of @code{@value{SUBSTITUTE-SERVER-1}} and
18089 @code{@value{SUBSTITUTE-SERVER-2}} (@pxref{Substitutes}). See
18090 @code{substitute-urls} below for an example on how to change it.
18092 @item @code{use-substitutes?} (default: @code{#t})
18093 Whether to use substitutes.
18095 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
18096 The list of URLs where to look for substitutes by default.
18098 Suppose you would like to fetch substitutes from @code{guix.example.org}
18099 in addition to @code{@value{SUBSTITUTE-SERVER-1}}. You will need to do
18100 two things: (1) add @code{guix.example.org} to @code{substitute-urls},
18101 and (2) authorize its signing key, having done appropriate checks
18102 (@pxref{Substitute Server Authorization}). The configuration below does
18106 (guix-configuration
18108 (append (list "https://guix.example.org")
18109 %default-substitute-urls))
18111 (append (list (local-file "./guix.example.org-key.pub"))
18112 %default-authorized-guix-keys)))
18115 This example assumes that the file @file{./guix.example.org-key.pub}
18116 contains the public key that @code{guix.example.org} uses to sign
18119 @item @code{generate-substitute-key?} (default: @code{#t})
18120 Whether to generate a @dfn{substitute key pair} under
18121 @file{/etc/guix/signing-key.pub} and @file{/etc/guix/signing-key.sec} if
18122 there is not already one.
18124 This key pair is used when exporting store items, for instance with
18125 @command{guix publish} (@pxref{Invoking guix publish}) or @command{guix
18126 archive} (@pxref{Invoking guix archive}). Generating a key pair takes a
18127 few seconds when enough entropy is available and is only done once; you
18128 might want to turn it off for instance in a virtual machine that does
18129 not need it and where the extra boot time is a problem.
18131 @item @code{max-silent-time} (default: @code{0})
18132 @itemx @code{timeout} (default: @code{0})
18133 The number of seconds of silence and the number of seconds of activity,
18134 respectively, after which a build process times out. A value of zero
18135 disables the timeout.
18137 @item @code{log-compression} (default: @code{'gzip})
18138 The type of compression used for build logs---one of @code{gzip},
18139 @code{bzip2}, or @code{none}.
18141 @item @code{discover?} (default: @code{#f})
18142 Whether to discover substitute servers on the local network using mDNS
18145 @item @code{extra-options} (default: @code{'()})
18146 List of extra command-line options for @command{guix-daemon}.
18148 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
18149 File where @command{guix-daemon}'s standard output and standard error
18152 @cindex HTTP proxy, for @code{guix-daemon}
18153 @cindex proxy, for @code{guix-daemon} HTTP access
18154 @item @code{http-proxy} (default: @code{#f})
18155 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
18156 derivations and substitutes.
18158 It is also possible to change the daemon's proxy at run time through the
18159 @code{set-http-proxy} action, which restarts it:
18162 herd set-http-proxy guix-daemon http://localhost:8118
18165 To clear the proxy settings, run:
18168 herd set-http-proxy guix-daemon
18171 @item @code{tmpdir} (default: @code{#f})
18172 A directory path where the @command{guix-daemon} will perform builds.
18177 @deftp {Data Type} guix-extension
18179 This data type represents the parameters of the Guix build daemon that
18180 are extendable. This is the type of the object that must be used within
18181 a guix service extension.
18182 @xref{Service Composition}, for more information.
18185 @item @code{authorized-keys} (default: @code{'()})
18186 A list of file-like objects where each element contains a public key.
18188 @item @code{substitute-urls} (default: @code{'()})
18189 A list of strings where each element is a substitute URL.
18191 @item @code{chroot-directories} (default: @code{'()})
18192 A list of file-like objects or strings pointing to additional directories the build daemon can use.
18196 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
18197 Run @var{udev}, which populates the @file{/dev} directory dynamically.
18198 udev rules can be provided as a list of files through the @var{rules}
18199 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
18200 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
18201 creation of such rule files.
18203 The @command{herd rules udev} command, as root, returns the name of the
18204 directory containing all the active udev rules.
18207 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
18208 Return a udev-rule file named @var{file-name} containing the rules
18209 defined by the @var{contents} literal.
18211 In the following example, a rule for a USB device is defined to be
18212 stored in the file @file{90-usb-thing.rules}. The rule runs a script
18213 upon detecting a USB device with a given product identifier.
18216 (define %example-udev-rule
18218 "90-usb-thing.rules"
18219 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
18220 "ATTR@{product@}==\"Example\", "
18221 "RUN+=\"/path/to/script\"")))
18225 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
18226 [#:groups @var{groups}]
18227 Return a service that extends @code{udev-service-type } with @var{rules}
18228 and @code{account-service-type} with @var{groups} as system groups.
18229 This works by creating a singleton service type
18230 @code{@var{name}-udev-rules}, of which the returned service is an
18233 Here we show how it can be used to extend @code{udev-service-type} with the
18234 previously defined rule @code{%example-udev-rule}.
18240 (cons (udev-rules-service 'usb-thing %example-udev-rule)
18241 %desktop-services)))
18245 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
18246 Return a udev file named @var{file-name} containing the rules defined
18247 within @var{file}, a file-like object.
18249 The following example showcases how we can use an existing rule file.
18252 (use-modules (guix download) ;for url-fetch
18253 (guix packages) ;for origin
18256 (define %android-udev-rules
18258 "51-android-udev.rules"
18259 (let ((version "20170910"))
18262 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
18263 "android-udev-rules/" version "/51-android.rules"))
18265 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
18269 Additionally, Guix package definitions can be included in @var{rules} in
18270 order to extend the udev rules with the definitions found under their
18271 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
18272 @var{file->udev-rule} example, we could have used the
18273 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
18274 packages android)} module.
18276 The following example shows how to use the @var{android-udev-rules}
18277 package so that the Android tool @command{adb} can detect devices
18278 without root privileges. It also details how to create the
18279 @code{adbusers} group, which is required for the proper functioning of
18280 the rules defined within the @code{android-udev-rules} package. To
18281 create such a group, we must define it both as part of the
18282 @code{supplementary-groups} of our @code{user-account} declaration, as
18283 well as in the @var{groups} of the @code{udev-rules-service} procedure.
18286 (use-modules (gnu packages android) ;for android-udev-rules
18287 (gnu system shadow) ;for user-group
18292 (users (cons (user-account
18294 (supplementary-groups
18295 '("adbusers" ;for adb
18296 "wheel" "netdev" "audio" "video")))))
18299 (cons (udev-rules-service 'android android-udev-rules
18300 #:groups '("adbusers"))
18301 %desktop-services)))
18304 @defvr {Scheme Variable} urandom-seed-service-type
18305 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
18306 when rebooting. It also tries to seed @file{/dev/urandom} from
18307 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
18311 @defvr {Scheme Variable} %random-seed-file
18312 This is the name of the file where some random bytes are saved by
18313 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
18314 It defaults to @file{/var/lib/random-seed}.
18319 @defvr {Scheme Variable} gpm-service-type
18320 This is the type of the service that runs GPM, the @dfn{general-purpose
18321 mouse daemon}, which provides mouse support to the Linux console. GPM
18322 allows users to use the mouse in the console, notably to select, copy,
18325 The value for services of this type must be a @code{gpm-configuration}
18326 (see below). This service is not part of @code{%base-services}.
18329 @deftp {Data Type} gpm-configuration
18330 Data type representing the configuration of GPM.
18333 @item @code{options} (default: @code{%default-gpm-options})
18334 Command-line options passed to @command{gpm}. The default set of
18335 options instruct @command{gpm} to listen to mouse events on
18336 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
18339 @item @code{gpm} (default: @code{gpm})
18340 The GPM package to use.
18345 @anchor{guix-publish-service-type}
18346 @deffn {Scheme Variable} guix-publish-service-type
18347 This is the service type for @command{guix publish} (@pxref{Invoking
18348 guix publish}). Its value must be a @code{guix-publish-configuration}
18349 object, as described below.
18351 This assumes that @file{/etc/guix} already contains a signing key pair as
18352 created by @command{guix archive --generate-key} (@pxref{Invoking guix
18353 archive}). If that is not the case, the service will fail to start.
18356 @deftp {Data Type} guix-publish-configuration
18357 Data type representing the configuration of the @code{guix publish}
18361 @item @code{guix} (default: @code{guix})
18362 The Guix package to use.
18364 @item @code{port} (default: @code{80})
18365 The TCP port to listen for connections.
18367 @item @code{host} (default: @code{"localhost"})
18368 The host (and thus, network interface) to listen to. Use
18369 @code{"0.0.0.0"} to listen on all the network interfaces.
18371 @item @code{advertise?} (default: @code{#f})
18372 When true, advertise the service on the local network @i{via} the DNS-SD
18373 protocol, using Avahi.
18375 This allows neighboring Guix devices with discovery on (see
18376 @code{guix-configuration} above) to discover this @command{guix publish}
18377 instance and to automatically download substitutes from it.
18379 @item @code{compression} (default: @code{'(("gzip" 3) ("zstd" 3))})
18380 This is a list of compression method/level tuple used when compressing
18381 substitutes. For example, to compress all substitutes with @emph{both} lzip
18382 at level 7 and gzip at level 9, write:
18385 '(("lzip" 7) ("gzip" 9))
18388 Level 9 achieves the best compression ratio at the expense of increased CPU
18389 usage, whereas level 1 achieves fast compression. @xref{Invoking guix
18390 publish}, for more information on the available compression methods and
18391 the tradeoffs involved.
18393 An empty list disables compression altogether.
18395 @item @code{nar-path} (default: @code{"nar"})
18396 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
18397 publish, @option{--nar-path}}, for details.
18399 @item @code{cache} (default: @code{#f})
18400 When it is @code{#f}, disable caching and instead generate archives on
18401 demand. Otherwise, this should be the name of a directory---e.g.,
18402 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
18403 archives and meta-data ready to be sent. @xref{Invoking guix publish,
18404 @option{--cache}}, for more information on the tradeoffs involved.
18406 @item @code{workers} (default: @code{#f})
18407 When it is an integer, this is the number of worker threads used for
18408 caching; when @code{#f}, the number of processors is used.
18409 @xref{Invoking guix publish, @option{--workers}}, for more information.
18411 @item @code{cache-bypass-threshold} (default: 10 MiB)
18412 When @code{cache} is true, this is the maximum size in bytes of a store
18413 item for which @command{guix publish} may bypass its cache in case of a
18414 cache miss. @xref{Invoking guix publish,
18415 @option{--cache-bypass-threshold}}, for more information.
18417 @item @code{ttl} (default: @code{#f})
18418 When it is an integer, this denotes the @dfn{time-to-live} in seconds
18419 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
18420 for more information.
18422 @item @code{negative-ttl} (default: @code{#f})
18423 When it is an integer, this denotes the @dfn{time-to-live} in
18424 seconds for the negative lookups. @xref{Invoking guix publish,
18425 @option{--negative-ttl}}, for more information.
18429 @anchor{rngd-service}
18430 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
18431 [#:device "/dev/hwrng"]
18432 Return a service that runs the @command{rngd} program from @var{rng-tools}
18433 to add @var{device} to the kernel's entropy pool. The service will fail if
18434 @var{device} does not exist.
18437 @anchor{pam-limits-service}
18438 @cindex session limits
18444 @cindex open file descriptors
18445 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
18447 Return a service that installs a configuration file for the
18448 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
18449 @code{pam_limits} module}. The procedure optionally takes a list of
18450 @code{pam-limits-entry} values, which can be used to specify
18451 @code{ulimit} limits and @code{nice} priority limits to user sessions.
18453 The following limits definition sets two hard and soft limits for all
18454 login sessions of users in the @code{realtime} group:
18457 (pam-limits-service
18459 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
18460 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
18463 The first entry increases the maximum realtime priority for
18464 non-privileged processes; the second entry lifts any restriction of the
18465 maximum address space that can be locked in memory. These settings are
18466 commonly used for real-time audio systems.
18468 Another useful example is raising the maximum number of open file
18469 descriptors that can be used:
18472 (pam-limits-service
18474 (pam-limits-entry "*" 'both 'nofile 100000)))
18477 In the above example, the asterisk means the limit should apply to any
18478 user. It is important to ensure the chosen value doesn't exceed the
18479 maximum system value visible in the @file{/proc/sys/fs/file-max} file,
18480 else the users would be prevented from login in. For more information
18481 about the Pluggable Authentication Module (PAM) limits, refer to the
18482 @samp{pam_limits} man page from the @code{linux-pam} package.
18485 @defvr {Scheme Variable} greetd-service-type
18486 @uref{https://git.sr.ht/~kennylevinsen/greetd, @code{greetd}} is a minimal and
18487 flexible login manager daemon, that makes no assumptions about what you
18490 If you can run it from your shell in a TTY, greetd can start it. If it
18491 can be taught to speak a simple JSON-based IPC protocol, then it can be
18494 @code{greetd-service-type} provides necessary infrastructure for logging
18495 in users, including:
18499 @code{greetd} PAM service
18502 Special variation of @code{pam-mount} to mount @code{XDG_RUNTIME_DIR}
18505 Here is example of switching from @code{mingetty-service-type} to
18506 @code{greetd-service-type}, and how different terminals could be:
18510 (modify-services %base-services
18511 ;; greetd-service-type provides "greetd" PAM service
18512 (delete login-service-type)
18513 ;; and can be used in place of mingetty-service-type
18514 (delete mingetty-service-type))
18516 (service greetd-service-type
18517 (greetd-configuration
18520 ;; we can make any terminal active by default
18521 (greetd-terminal-configuration (terminal-vt "1") (terminal-switch #t))
18522 ;; we can make environment without XDG_RUNTIME_DIR set
18523 ;; even provide our own environment variables
18524 (greetd-terminal-configuration
18526 (default-session-command
18527 (greetd-agreety-session
18528 (extra-env '(("MY_VAR" . "1")))
18530 ;; we can use different shell instead of default bash
18531 (greetd-terminal-configuration
18533 (default-session-command
18534 (greetd-agreety-session (command (file-append zsh "/bin/zsh")))))
18535 ;; we can use any other executable command as greeter
18536 (greetd-terminal-configuration
18538 (default-session-command (program-file "my-noop-greeter" #~(exit))))
18539 (greetd-terminal-configuration (terminal-vt "5"))
18540 (greetd-terminal-configuration (terminal-vt "6"))))))
18541 ;; mingetty-service-type can be used in parallel
18542 ;; if needed to do so, do not (delete login-service-type)
18543 ;; as illustrated above
18544 #| (service mingetty-service-type (mingetty-configuration (tty "tty8"))) |#))
18548 @deftp {Data Type} greetd-configuration
18549 Configuration record for the @code{greetd-service-type}.
18553 A file-like object containing the ``message of the day''.
18555 @item @code{allow-empty-passwords?} (default: @code{#t})
18556 Allow empty passwords by default so that first-time users can log in when
18557 the 'root' account has just been created.
18559 @item @code{terminals} (default: @code{'()})
18560 List of @code{greetd-terminal-configuration} per terminal for which
18561 @code{greetd} should be started.
18563 @item @code{greeter-supplementary-groups} (default: @code{'()})
18564 List of groups which should be added to @code{greeter} user. For instance:
18566 (greeter-supplementary-groups '("seat" "video"))
18568 Note that this example will fail if @code{seat} group does not exist.
18572 @deftp {Data Type} greetd-terminal-configuration
18573 Configuration record for per terminal greetd daemon service.
18576 @item @code{greetd} (default: @code{greetd})
18577 The greetd package to use.
18579 @item @code{config-file-name}
18580 Configuration file name to use for greetd daemon. Generally, autogenerated
18581 derivation based on @code{terminal-vt} value.
18583 @item @code{log-file-name}
18584 Log file name to use for greetd daemon. Generally, autogenerated
18585 name based on @code{terminal-vt} value.
18587 @item @code{terminal-vt} (default: @samp{"7"})
18588 The VT to run on. Use of a specific VT with appropriate conflict avoidance
18591 @item @code{terminal-switch} (default: @code{#f})
18592 Make this terminal active on start of @code{greetd}.
18594 @item @code{default-session-user} (default: @samp{"greeter"})
18595 The user to use for running the greeter.
18597 @item @code{default-session-command} (default: @code{(greetd-agreety-session)})
18598 Can be either instance of @code{greetd-agreety-session} configuration or
18599 @code{gexp->script} like object to use as greeter.
18604 @deftp {Data Type} greetd-agreety-session
18605 Configuration record for the agreety greetd greeter.
18608 @item @code{agreety} (default: @code{greetd})
18609 The package with @command{/bin/agreety} command.
18611 @item @code{command} (default: @code{(file-append bash "/bin/bash")})
18612 Command to be started by @command{/bin/agreety} on successful login.
18614 @item @code{command-args} (default: @code{'("-l")})
18615 Command arguments to pass to command.
18617 @item @code{extra-env} (default: @code{'()})
18618 Extra environment variables to set on login.
18620 @item @code{xdg-env?} (default: @code{#t})
18621 If true @code{XDG_RUNTIME_DIR} and @code{XDG_SESSION_TYPE} will be set
18622 before starting command. One should note that, @code{extra-env} variables
18623 are set right after mentioned variables, so that they can be overriden.
18628 @node Scheduled Job Execution
18629 @subsection Scheduled Job Execution
18633 @cindex scheduling jobs
18634 The @code{(gnu services mcron)} module provides an interface to
18635 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
18636 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
18637 Unix @command{cron} daemon; the main difference is that it is
18638 implemented in Guile Scheme, which provides a lot of flexibility when
18639 specifying the scheduling of jobs and their actions.
18641 The example below defines an operating system that runs the
18642 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
18643 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
18644 well as the @command{mkid} command on behalf of an unprivileged user
18645 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
18646 gexps to introduce job definitions that are passed to mcron
18647 (@pxref{G-Expressions}).
18650 (use-modules (guix) (gnu) (gnu services mcron))
18651 (use-package-modules base idutils)
18653 (define updatedb-job
18654 ;; Run 'updatedb' at 3AM every day. Here we write the
18655 ;; job's action as a Scheme procedure.
18656 #~(job '(next-hour '(3))
18658 (execl (string-append #$findutils "/bin/updatedb")
18660 "--prunepaths=/tmp /var/tmp /gnu/store"))
18663 (define garbage-collector-job
18664 ;; Collect garbage 5 minutes after midnight every day.
18665 ;; The job's action is a shell command.
18666 #~(job "5 0 * * *" ;Vixie cron syntax
18669 (define idutils-job
18670 ;; Update the index database as user "charlie" at 12:15PM
18671 ;; and 19:15PM. This runs from the user's home directory.
18672 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
18673 (string-append #$idutils "/bin/mkid src")
18679 ;; %BASE-SERVICES already includes an instance of
18680 ;; 'mcron-service-type', which we extend with additional
18681 ;; jobs using 'simple-service'.
18682 (services (cons (simple-service 'my-cron-jobs
18684 (list garbage-collector-job
18691 When providing the action of a job specification as a procedure, you
18692 should provide an explicit name for the job via the optional 3rd
18693 argument as done in the @code{updatedb-job} example above. Otherwise,
18694 the job would appear as ``Lambda function'' in the output of
18695 @command{herd schedule mcron}, which is not nearly descriptive enough!
18698 For more complex jobs defined in Scheme where you need control over the top
18699 level, for instance to introduce a @code{use-modules} form, you can move your
18700 code to a separate program using the @code{program-file} procedure of the
18701 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
18705 (define %battery-alert-job
18706 ;; Beep when the battery percentage falls below %MIN-LEVEL.
18708 '(next-minute (range 0 60 1))
18710 "battery-alert.scm"
18711 (with-imported-modules (source-module-closure
18712 '((guix build utils)))
18714 (use-modules (guix build utils)
18717 (ice-9 textual-ports)
18720 (define %min-level 20)
18722 (setenv "LC_ALL" "C") ;ensure English output
18723 (and-let* ((input-pipe (open-pipe*
18725 #$(file-append acpi "/bin/acpi")))
18726 (output (get-string-all input-pipe))
18727 (m (string-match "Discharging, ([0-9]+)%" output))
18728 (level (string->number (match:substring m 1)))
18729 ((< level %min-level)))
18730 (format #t "warning: Battery level is low (~a%)~%" level)
18731 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
18734 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
18735 for more information on mcron job specifications. Below is the
18736 reference of the mcron service.
18738 On a running system, you can use the @code{schedule} action of the service to
18739 visualize the mcron jobs that will be executed next:
18742 # herd schedule mcron
18746 The example above lists the next five tasks that will be executed, but you can
18747 also specify the number of tasks to display:
18750 # herd schedule mcron 10
18753 @defvr {Scheme Variable} mcron-service-type
18754 This is the type of the @code{mcron} service, whose value is an
18755 @code{mcron-configuration} object.
18757 This service type can be the target of a service extension that provides
18758 additional job specifications (@pxref{Service Composition}). In other
18759 words, it is possible to define services that provide additional mcron
18763 @deftp {Data Type} mcron-configuration
18764 Data type representing the configuration of mcron.
18767 @item @code{mcron} (default: @var{mcron})
18768 The mcron package to use.
18771 This is a list of gexps (@pxref{G-Expressions}), where each gexp
18772 corresponds to an mcron job specification (@pxref{Syntax, mcron job
18773 specifications,, mcron, GNU@tie{}mcron}).
18779 @subsection Log Rotation
18782 @cindex log rotation
18784 Log files such as those found in @file{/var/log} tend to grow endlessly,
18785 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
18786 their contents in separate files, possibly compressed. The @code{(gnu
18787 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
18788 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
18790 This service is part of @code{%base-services}, and thus enabled by
18791 default, with the default settings, for commonly encountered log files.
18792 The example below shows how to extend it with an additional
18793 @dfn{rotation}, should you need to do that (usually, services that
18794 produce log files already take care of that):
18797 (use-modules (guix) (gnu))
18798 (use-service-modules admin)
18800 (define my-log-files
18801 ;; Log files that I want to rotate.
18802 '("/var/log/something.log" "/var/log/another.log"))
18806 (services (cons (simple-service 'rotate-my-stuff
18807 rottlog-service-type
18808 (list (log-rotation
18810 (files my-log-files))))
18814 @defvr {Scheme Variable} rottlog-service-type
18815 This is the type of the Rottlog service, whose value is a
18816 @code{rottlog-configuration} object.
18818 Other services can extend this one with new @code{log-rotation} objects
18819 (see below), thereby augmenting the set of files to be rotated.
18821 This service type can define mcron jobs (@pxref{Scheduled Job
18822 Execution}) to run the rottlog service.
18825 @deftp {Data Type} rottlog-configuration
18826 Data type representing the configuration of rottlog.
18829 @item @code{rottlog} (default: @code{rottlog})
18830 The Rottlog package to use.
18832 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
18833 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
18834 rottlog, GNU Rot[t]log Manual}).
18836 @item @code{rotations} (default: @code{%default-rotations})
18837 A list of @code{log-rotation} objects as defined below.
18840 This is a list of gexps where each gexp corresponds to an mcron job
18841 specification (@pxref{Scheduled Job Execution}).
18845 @deftp {Data Type} log-rotation
18846 Data type representing the rotation of a group of log files.
18848 Taking an example from the Rottlog manual (@pxref{Period Related File
18849 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
18855 (files '("/var/log/apache/*"))
18856 (options '("storedir apache-archives"
18862 The list of fields is as follows:
18865 @item @code{frequency} (default: @code{'weekly})
18866 The log rotation frequency, a symbol.
18869 The list of files or file glob patterns to rotate.
18871 @vindex %default-log-rotation-options
18872 @item @code{options} (default: @code{%default-log-rotation-options})
18873 The list of rottlog options for this rotation (@pxref{Configuration
18874 parameters,,, rottlog, GNU Rot[t]log Manual}).
18876 @item @code{post-rotate} (default: @code{#f})
18877 Either @code{#f} or a gexp to execute once the rotation has completed.
18881 @defvr {Scheme Variable} %default-rotations
18882 Specifies weekly rotation of @code{%rotated-files} and of
18883 @file{/var/log/guix-daemon.log}.
18886 @defvr {Scheme Variable} %rotated-files
18887 The list of syslog-controlled files to be rotated. By default it is:
18888 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
18889 "/var/log/maillog")}.
18892 Some log files just need to be deleted periodically once they are old,
18893 without any other criterion and without any archival step. This is the
18894 case of build logs stored by @command{guix-daemon} under
18895 @file{/var/log/guix/drvs} (@pxref{Invoking guix-daemon}). The
18896 @code{log-cleanup} service addresses this use case. For example,
18897 @code{%base-services} (@pxref{Base Services}) includes the following:
18900 ;; Periodically delete old build logs.
18901 (service log-cleanup-service-type
18902 (log-cleanup-configuration
18903 (directory "/var/log/guix/drvs")))
18906 That ensures build logs do not accumulate endlessly.
18908 @defvr {Scheme Variable} log-cleanup-service-type
18909 This is the type of the service to delete old logs. Its value must be a
18910 @code{log-cleanup-configuration} record as described below.
18913 @deftp {Data Type} log-cleanup-configuration
18914 Data type representing the log cleanup configuration
18917 @item @code{directory}
18918 Name of the directory containing log files.
18920 @item @code{expiry} (default: @code{(* 6 30 24 3600)})
18921 Age in seconds after which a file is subject to deletion (six months by
18924 @item @code{schedule} (default: @code{"30 12 01,08,15,22 * *"})
18925 String or gexp denoting the corresponding mcron job schedule
18926 (@pxref{Scheduled Job Execution}).
18930 @cindex logging, anonymization
18931 @subheading Anonip Service
18933 Anonip is a privacy filter that removes IP address from web server logs.
18934 This service creates a FIFO and filters any written lines with anonip
18935 before writing the filtered log to a target file.
18937 The following example sets up the FIFO
18938 @file{/var/run/anonip/https.access.log} and writes the filtered log file
18939 @file{/var/log/anonip/https.access.log}.
18942 (service anonip-service-type
18943 (anonip-configuration
18944 (input "/var/run/anonip/https.access.log")
18945 (output "/var/log/anonip/https.access.log")))
18948 Configure your web server to write its logs to the FIFO at
18949 @file{/var/run/anonip/https.access.log} and collect the anonymized log
18950 file at @file{/var/web-logs/https.access.log}.
18952 @deftp {Data Type} anonip-configuration
18953 This data type represents the configuration of anonip.
18954 It has the following parameters:
18957 @item @code{anonip} (default: @code{anonip})
18958 The anonip package to use.
18961 The file name of the input log file to process. The service creates a
18962 FIFO of this name. The web server should write its logs to this FIFO.
18964 @item @code{output}
18965 The file name of the processed log file.
18968 The following optional settings may be provided:
18971 @item @code{skip-private?}
18972 When @code{#true} do not mask addresses in private ranges.
18974 @item @code{column}
18975 A 1-based indexed column number. Assume IP address is in the specified
18976 column (default is 1).
18978 @item @code{replacement}
18979 Replacement string in case address parsing fails, e.g. @code{"0.0.0.0"}.
18981 @item @code{ipv4mask}
18982 Number of bits to mask in IPv4 addresses.
18984 @item @code{ipv6mask}
18985 Number of bits to mask in IPv6 addresses.
18987 @item @code{increment}
18988 Increment the IP address by the given number. By default this is zero.
18990 @item @code{delimiter}
18991 Log delimiter string.
18994 Regular expression for detecting IP addresses. Use this instead of @code{column}.
18999 @node Networking Setup
19000 @subsection Networking Setup
19002 The @code{(gnu services networking)} module provides services to
19003 configure network interfaces and set up networking on your machine.
19004 Those services provide different ways for you to set up your machine: by
19005 declaring a static network configuration, by running a Dynamic Host
19006 Configuration Protocol (DHCP) client, or by running daemons such as
19007 NetworkManager and Connman that automate the whole process,
19008 automatically adapt to connectivity changes, and provide a high-level
19011 On a laptop, NetworkManager and Connman are by far the most convenient
19012 options, which is why the default desktop services include
19013 NetworkManager (@pxref{Desktop Services, @code{%desktop-services}}).
19014 For a server, or for a virtual machine or a container, static network
19015 configuration or a simple DHCP client are often more appropriate.
19017 This section describes the various network setup services available,
19018 starting with static network configuration.
19020 @defvr {Scheme Variable} static-networking-service-type
19021 This is the type for statically-configured network interfaces. Its
19022 value must be a list of @code{static-networking} records. Each of them
19023 declares a set of @dfn{addresses}, @dfn{routes}, and @dfn{links}, as
19026 @cindex network interface controller (NIC)
19027 @cindex NIC, networking interface controller
19028 Here is the simplest configuration, with only one network interface
19029 controller (NIC) and only IPv4 connectivity:
19032 ;; Static networking for one NIC, IPv4-only.
19033 (service static-networking-service-type
19034 (list (static-networking
19036 (list (network-address
19038 (value "10.0.2.15/24"))))
19040 (list (network-route
19041 (destination "default")
19042 (gateway "10.0.2.2"))))
19043 (name-servers '("10.0.2.3")))))
19046 The snippet above can be added to the @code{services} field of your
19047 operating system configuration (@pxref{Using the Configuration System}).
19048 It will configure your machine to have 10.0.2.15 as its IP address, with
19049 a 24-bit netmask for the local network---meaning that any 10.0.2.@var{x}
19050 address is on the local area network (LAN). Traffic to addresses
19051 outside the local network is routed @i{via} 10.0.2.2. Host names are
19052 resolved by sending domain name system (DNS) queries to 10.0.2.3.
19055 @deftp {Data Type} static-networking
19056 This is the data type representing a static network configuration.
19058 As an example, here is how you would declare the configuration of a
19059 machine with a single network interface controller (NIC) available as
19060 @code{eno1}, and with one IPv4 and one IPv6 address:
19063 ;; Network configuration for one NIC, IPv4 + IPv6.
19065 (addresses (list (network-address
19067 (value "10.0.2.15/24"))
19070 (value "2001:123:4567:101::1/64"))))
19071 (routes (list (network-route
19072 (destination "default")
19073 (gateway "10.0.2.2"))
19075 (destination "default")
19076 (gateway "2020:321:4567:42::1"))))
19077 (name-servers '("10.0.2.3")))
19080 If you are familiar with the @command{ip} command of the
19081 @uref{https://wiki.linuxfoundation.org/networking/iproute2,
19082 @code{iproute2} package} found on Linux-based systems, the declaration
19083 above is equivalent to typing:
19086 ip address add 10.0.2.15/24 dev eno1
19087 ip address add 2001:123:4567:101::1/64 dev eno1
19088 ip route add default via inet 10.0.2.2
19089 ip route add default via inet6 2020:321:4567:42::1
19092 Run @command{man 8 ip} for more info. Venerable GNU/Linux users will
19093 certainly know how to do it with @command{ifconfig} and @command{route},
19094 but we'll spare you that.
19096 The available fields of this data type are as follows:
19099 @item @code{addresses}
19100 @itemx @code{links} (default: @code{'()})
19101 @itemx @code{routes} (default: @code{'()})
19102 The list of @code{network-address}, @code{network-link}, and
19103 @code{network-route} records for this network (see below).
19105 @item @code{name-servers} (default: @code{'()})
19106 The list of IP addresses (strings) of domain name servers. These IP
19107 addresses go to @file{/etc/resolv.conf}.
19109 @item @code{provision} (default: @code{'(networking)})
19110 If true, this should be a list of symbols for the Shepherd service
19111 corresponding to this network configuration.
19113 @item @code{requirement} (default @code{'()})
19114 The list of Shepherd services depended on.
19118 @deftp {Data Type} network-address
19119 This is the data type representing the IP address of a network
19124 The name of the network interface for this address---e.g.,
19128 The actual IP address and network mask, in
19129 @uref{https://en.wikipedia.org/wiki/CIDR#CIDR_notation, @acronym{CIDR,
19130 Classless Inter-Domain Routing} notation}, as a string.
19132 For example, @code{"10.0.2.15/24"} denotes IPv4 address 10.0.2.15 on a
19133 24-bit sub-network---all 10.0.2.@var{x} addresses are on the same local
19137 Whether @code{value} denotes an IPv6 address. By default this is
19138 automatically determined.
19142 @deftp {Data Type} network-route
19143 This is the data type representing a network route.
19146 @item @code{destination}
19147 The route destination (a string), either an IP address or
19148 @code{"default"} to denote the default route.
19150 @item @code{source} (default: @code{#f})
19153 @item @code{device} (default: @code{#f})
19154 The device used for this route---e.g., @code{"eno2"}.
19156 @item @code{ipv6?} (default: auto)
19157 Whether this is an IPv6 route. By default this is automatically
19158 determined based on @code{destination} or @code{gateway}.
19160 @item @code{gateway} (default: @code{#f})
19161 IP address (a string) through which traffic is routed.
19165 @deftp {Data Type} network-link
19166 Data type for a network link (@pxref{Link,,, guile-netlink,
19167 Guile-Netlink Manual}).
19171 The name of the link---e.g., @code{"v0p0"}.
19174 A symbol denoting the type of the link---e.g., @code{'veth}.
19177 List of arguments for this type of link.
19181 @cindex loopback device
19182 @defvr {Scheme Variable} %loopback-static-networking
19183 This is the @code{static-networking} record representing the ``loopback
19184 device'', @code{lo}, for IP addresses 127.0.0.1 and ::1, and providing
19185 the @code{loopback} Shepherd service.
19188 @cindex networking, with QEMU
19189 @cindex QEMU, networking
19190 @defvr {Scheme Variable} %qemu-static-networking
19191 This is the @code{static-networking} record representing network setup
19192 when using QEMU's user-mode network stack on @code{eth0} (@pxref{Using
19193 the user mode network stack,,, QEMU, QEMU Documentation}).
19196 @cindex DHCP, networking service
19197 @defvr {Scheme Variable} dhcp-client-service-type
19198 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
19199 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
19200 is the DHCP client package to use, @code{isc-dhcp} by default.
19203 @cindex NetworkManager
19205 @defvr {Scheme Variable} network-manager-service-type
19206 This is the service type for the
19207 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
19208 service. The value for this service type is a
19209 @code{network-manager-configuration} record.
19211 This service is part of @code{%desktop-services} (@pxref{Desktop
19215 @deftp {Data Type} network-manager-configuration
19216 Data type representing the configuration of NetworkManager.
19219 @item @code{network-manager} (default: @code{network-manager})
19220 The NetworkManager package to use.
19222 @item @code{dns} (default: @code{"default"})
19223 Processing mode for DNS, which affects how NetworkManager uses the
19224 @code{resolv.conf} configuration file.
19228 NetworkManager will update @code{resolv.conf} to reflect the nameservers
19229 provided by currently active connections.
19232 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
19233 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
19234 then update @code{resolv.conf} to point to the local nameserver.
19236 With this setting, you can share your network connection. For example when
19237 you want to share your network connection to another laptop @i{via} an
19238 Ethernet cable, you can open @command{nm-connection-editor} and configure the
19239 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
19240 and reestablish the connection (or reboot).
19242 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
19243 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
19244 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
19245 browser on your host system, or connect to the VM @i{via} SSH
19246 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
19247 host-to-guest connection, run this command once:
19250 nmcli connection add type tun \
19251 connection.interface-name tap0 \
19252 tun.mode tap tun.owner $(id -u) \
19253 ipv4.method shared \
19254 ipv4.addresses 172.28.112.1/24
19257 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
19258 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
19259 @command{qemu-system-...}.
19262 NetworkManager will not modify @code{resolv.conf}.
19265 @item @code{vpn-plugins} (default: @code{'()})
19266 This is the list of available plugins for virtual private networks
19267 (VPNs). An example of this is the @code{network-manager-openvpn}
19268 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
19274 @deffn {Scheme Variable} connman-service-type
19275 This is the service type to run @url{https://01.org/connman,Connman},
19276 a network connection manager.
19278 Its value must be an
19279 @code{connman-configuration} record as in this example:
19282 (service connman-service-type
19283 (connman-configuration
19284 (disable-vpn? #t)))
19287 See below for details about @code{connman-configuration}.
19290 @deftp {Data Type} connman-configuration
19291 Data Type representing the configuration of connman.
19294 @item @code{connman} (default: @var{connman})
19295 The connman package to use.
19297 @item @code{disable-vpn?} (default: @code{#f})
19298 When true, disable connman's vpn plugin.
19302 @cindex WPA Supplicant
19303 @defvr {Scheme Variable} wpa-supplicant-service-type
19304 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
19305 supplicant}, an authentication daemon required to authenticate against
19306 encrypted WiFi or ethernet networks.
19309 @deftp {Data Type} wpa-supplicant-configuration
19310 Data type representing the configuration of WPA Supplicant.
19312 It takes the following parameters:
19315 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
19316 The WPA Supplicant package to use.
19318 @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
19319 List of services that should be started before WPA Supplicant starts.
19321 @item @code{dbus?} (default: @code{#t})
19322 Whether to listen for requests on D-Bus.
19324 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
19325 Where to store the PID file.
19327 @item @code{interface} (default: @code{#f})
19328 If this is set, it must specify the name of a network interface that
19329 WPA supplicant will control.
19331 @item @code{config-file} (default: @code{#f})
19332 Optional configuration file to use.
19334 @item @code{extra-options} (default: @code{'()})
19335 List of additional command-line arguments to pass to the daemon.
19339 @cindex ModemManager
19340 Some networking devices such as modems require special care, and this is
19341 what the services below focus on.
19343 @defvr {Scheme Variable} modem-manager-service-type
19344 This is the service type for the
19345 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
19346 service. The value for this service type is a
19347 @code{modem-manager-configuration} record.
19349 This service is part of @code{%desktop-services} (@pxref{Desktop
19353 @deftp {Data Type} modem-manager-configuration
19354 Data type representing the configuration of ModemManager.
19357 @item @code{modem-manager} (default: @code{modem-manager})
19358 The ModemManager package to use.
19363 @cindex USB_ModeSwitch
19364 @cindex Modeswitching
19366 @defvr {Scheme Variable} usb-modeswitch-service-type
19367 This is the service type for the
19368 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch}
19369 service. The value for this service type is
19370 a @code{usb-modeswitch-configuration} record.
19372 When plugged in, some USB modems (and other USB devices) initially present
19373 themselves as a read-only storage medium and not as a modem. They need to be
19374 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
19375 installs udev rules to automatically modeswitch these devices when they are
19378 This service is part of @code{%desktop-services} (@pxref{Desktop
19382 @deftp {Data Type} usb-modeswitch-configuration
19383 Data type representing the configuration of USB_ModeSwitch.
19386 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
19387 The USB_ModeSwitch package providing the binaries for modeswitching.
19389 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
19390 The package providing the device data and udev rules file used by
19393 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
19394 Which config file to use for the USB_ModeSwitch dispatcher. By default the
19395 config file shipped with USB_ModeSwitch is used which disables logging to
19396 @file{/var/log} among other default settings. If set to @code{#f}, no config
19403 @node Networking Services
19404 @subsection Networking Services
19406 The @code{(gnu services networking)} module discussed in the previous
19407 section provides services for more advanced setups: providing a DHCP
19408 service for others to use, filtering packets with iptables or nftables,
19409 running a WiFi access point with @command{hostapd}, running the
19410 @command{inetd} ``superdaemon'', and more. This section describes
19413 @deffn {Scheme Procedure} dhcpd-service-type
19414 This type defines a service that runs a DHCP daemon. To create a
19415 service of this type, you must supply a @code{<dhcpd-configuration>}.
19419 (service dhcpd-service-type
19420 (dhcpd-configuration
19421 (config-file (local-file "my-dhcpd.conf"))
19422 (interfaces '("enp0s25"))))
19426 @deftp {Data Type} dhcpd-configuration
19428 @item @code{package} (default: @code{isc-dhcp})
19429 The package that provides the DHCP daemon. This package is expected to
19430 provide the daemon at @file{sbin/dhcpd} relative to its output
19431 directory. The default package is the
19432 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
19433 @item @code{config-file} (default: @code{#f})
19434 The configuration file to use. This is required. It will be passed to
19435 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
19436 object (@pxref{G-Expressions, file-like objects}). See @code{man
19437 dhcpd.conf} for details on the configuration file syntax.
19438 @item @code{version} (default: @code{"4"})
19439 The DHCP version to use. The ISC DHCP server supports the values ``4'',
19440 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
19441 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
19443 @item @code{run-directory} (default: @code{"/run/dhcpd"})
19444 The run directory to use. At service activation time, this directory
19445 will be created if it does not exist.
19446 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
19447 The PID file to use. This corresponds to the @code{-pf} option of
19448 @code{dhcpd}. See @code{man dhcpd} for details.
19449 @item @code{interfaces} (default: @code{'()})
19450 The names of the network interfaces on which dhcpd should listen for
19451 broadcasts. If this list is not empty, then its elements (which must be
19452 strings) will be appended to the @code{dhcpd} invocation when starting
19453 the daemon. It may not be necessary to explicitly specify any
19454 interfaces here; see @code{man dhcpd} for details.
19458 @cindex hostapd service, for Wi-Fi access points
19459 @cindex Wi-Fi access points, hostapd service
19460 @defvr {Scheme Variable} hostapd-service-type
19461 This is the service type to run the @uref{https://w1.fi/hostapd/,
19462 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
19463 authentication servers. Its associated value must be a
19464 @code{hostapd-configuration} as shown below:
19467 ;; Use wlan1 to run the access point for "My Network".
19468 (service hostapd-service-type
19469 (hostapd-configuration
19470 (interface "wlan1")
19471 (ssid "My Network")
19476 @deftp {Data Type} hostapd-configuration
19477 This data type represents the configuration of the hostapd service, with
19478 the following fields:
19481 @item @code{package} (default: @code{hostapd})
19482 The hostapd package to use.
19484 @item @code{interface} (default: @code{"wlan0"})
19485 The network interface to run the WiFi access point.
19488 The SSID (@dfn{service set identifier}), a string that identifies this
19491 @item @code{broadcast-ssid?} (default: @code{#t})
19492 Whether to broadcast this SSID.
19494 @item @code{channel} (default: @code{1})
19495 The WiFi channel to use.
19497 @item @code{driver} (default: @code{"nl80211"})
19498 The driver interface type. @code{"nl80211"} is used with all Linux
19499 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
19500 RADIUS server that does # not control any wireless/wired driver.
19502 @item @code{extra-settings} (default: @code{""})
19503 Extra settings to append as-is to the hostapd configuration file. See
19504 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
19505 configuration file reference.
19509 @defvr {Scheme Variable} simulated-wifi-service-type
19510 This is the type of a service to simulate WiFi networking, which can be
19511 useful in virtual machines for testing purposes. The service loads the
19513 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
19514 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
19515 network that can be seen on @code{wlan0}, by default.
19517 The service's value is a @code{hostapd-configuration} record.
19522 @defvr {Scheme Variable} iptables-service-type
19523 This is the service type to set up an iptables configuration. iptables is a
19524 packet filtering framework supported by the Linux kernel. This service
19525 supports configuring iptables for both IPv4 and IPv6. A simple example
19526 configuration rejecting all incoming connections except those to the ssh port
19530 (service iptables-service-type
19531 (iptables-configuration
19532 (ipv4-rules (plain-file "iptables.rules" "*filter
19536 -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
19537 -A INPUT -p tcp --dport 22 -j ACCEPT
19538 -A INPUT -j REJECT --reject-with icmp-port-unreachable
19541 (ipv6-rules (plain-file "ip6tables.rules" "*filter
19545 -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
19546 -A INPUT -p tcp --dport 22 -j ACCEPT
19547 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
19553 @deftp {Data Type} iptables-configuration
19554 The data type representing the configuration of iptables.
19557 @item @code{iptables} (default: @code{iptables})
19558 The iptables package that provides @code{iptables-restore} and
19559 @code{ip6tables-restore}.
19560 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
19561 The iptables rules to use. It will be passed to @code{iptables-restore}.
19562 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
19564 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
19565 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
19566 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
19572 @defvr {Scheme Variable} nftables-service-type
19573 This is the service type to set up a nftables configuration. nftables is a
19574 netfilter project that aims to replace the existing iptables, ip6tables,
19575 arptables and ebtables framework. It provides a new packet filtering
19576 framework, a new user-space utility @command{nft}, and a compatibility layer
19577 for iptables. This service comes with a default ruleset
19578 @code{%default-nftables-ruleset} that rejecting all incoming connections
19579 except those to the ssh port 22. To use it, simply write:
19582 (service nftables-service-type)
19586 @deftp {Data Type} nftables-configuration
19587 The data type representing the configuration of nftables.
19590 @item @code{package} (default: @code{nftables})
19591 The nftables package that provides @command{nft}.
19592 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
19593 The nftables ruleset to use. This may be any ``file-like'' object
19594 (@pxref{G-Expressions, file-like objects}).
19598 @cindex NTP (Network Time Protocol), service
19599 @cindex ntpd, service for the Network Time Protocol daemon
19600 @cindex real time clock
19601 @defvr {Scheme Variable} ntp-service-type
19602 This is the type of the service running the @uref{https://www.ntp.org,
19603 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
19604 system clock synchronized with that of the specified NTP servers.
19606 The value of this service is an @code{ntpd-configuration} object, as described
19610 @deftp {Data Type} ntp-configuration
19611 This is the data type for the NTP service configuration.
19614 @item @code{servers} (default: @code{%ntp-servers})
19615 This is the list of servers (@code{<ntp-server>} records) with which
19616 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
19619 @item @code{allow-large-adjustment?} (default: @code{#t})
19620 This determines whether @command{ntpd} is allowed to make an initial
19621 adjustment of more than 1,000 seconds.
19623 @item @code{ntp} (default: @code{ntp})
19624 The NTP package to use.
19628 @defvr {Scheme Variable} %ntp-servers
19629 List of host names used as the default NTP servers. These are servers of the
19630 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
19633 @deftp {Data Type} ntp-server
19634 The data type representing the configuration of a NTP server.
19637 @item @code{type} (default: @code{'server})
19638 The type of the NTP server, given as a symbol. One of @code{'pool},
19639 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
19641 @item @code{address}
19642 The address of the server, as a string.
19644 @item @code{options}
19645 NTPD options to use with that specific server, given as a list of option names
19646 and/or of option names and values tuples. The following example define a server
19647 to use with the options @option{iburst} and @option{prefer}, as well as
19648 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
19653 (address "some.ntp.server.org")
19654 (options `(iburst (version 3) (maxpoll 16) prefer))))
19660 @deffn {Scheme Procedure} openntpd-service-type
19661 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
19662 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
19663 clock synchronized with that of the given servers.
19667 openntpd-service-type
19668 (openntpd-configuration
19669 (listen-on '("127.0.0.1" "::1"))
19670 (sensor '("udcf0 correction 70000"))
19671 (constraint-from '("www.gnu.org"))
19672 (constraints-from '("https://www.google.com/"))))
19677 @defvr {Scheme Variable} %openntpd-servers
19678 This variable is a list of the server addresses defined in
19679 @code{%ntp-servers}.
19682 @deftp {Data Type} openntpd-configuration
19684 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
19685 The openntpd executable to use.
19686 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
19687 A list of local IP addresses or hostnames the ntpd daemon should listen on.
19688 @item @code{query-from} (default: @code{'()})
19689 A list of local IP address the ntpd daemon should use for outgoing queries.
19690 @item @code{sensor} (default: @code{'()})
19691 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
19692 will listen to each sensor that actually exists and ignore non-existent ones.
19693 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
19695 @item @code{server} (default: @code{'()})
19696 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
19697 @item @code{servers} (default: @code{%openntp-servers})
19698 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
19699 @item @code{constraint-from} (default: @code{'()})
19700 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
19701 This time information is not used for precision but acts as an authenticated
19702 constraint, thereby reducing the impact of unauthenticated NTP
19703 man-in-the-middle attacks.
19704 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
19706 @item @code{constraints-from} (default: @code{'()})
19707 As with constraint from, specify a list of URLs, IP addresses or hostnames of
19708 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
19709 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
19714 @deffn {Scheme variable} inetd-service-type
19715 This service runs the @command{inetd} (@pxref{inetd invocation,,,
19716 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
19717 connections on internet sockets, and lazily starts the specified server
19718 program when a connection is made on one of these sockets.
19720 The value of this service is an @code{inetd-configuration} object. The
19721 following example configures the @command{inetd} daemon to provide the
19722 built-in @command{echo} service, as well as an smtp service which
19723 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
19724 gateway @code{hostname}:
19729 (inetd-configuration
19733 (socket-type 'stream)
19740 (socket-type 'stream)
19744 (program (file-append openssh "/bin/ssh"))
19746 '("ssh" "-qT" "-i" "/path/to/ssh_key"
19747 "-W" "smtp-server:25" "user@@hostname")))))))
19750 See below for more details about @code{inetd-configuration}.
19753 @deftp {Data Type} inetd-configuration
19754 Data type representing the configuration of @command{inetd}.
19757 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
19758 The @command{inetd} executable to use.
19760 @item @code{entries} (default: @code{'()})
19761 A list of @command{inetd} service entries. Each entry should be created
19762 by the @code{inetd-entry} constructor.
19766 @deftp {Data Type} inetd-entry
19767 Data type representing an entry in the @command{inetd} configuration.
19768 Each entry corresponds to a socket where @command{inetd} will listen for
19772 @item @code{node} (default: @code{#f})
19773 Optional string, a comma-separated list of local addresses
19774 @command{inetd} should use when listening for this service.
19775 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
19776 description of all options.
19778 A string, the name must correspond to an entry in @code{/etc/services}.
19779 @item @code{socket-type}
19780 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
19782 @item @code{protocol}
19783 A string, must correspond to an entry in @code{/etc/protocols}.
19784 @item @code{wait?} (default: @code{#t})
19785 Whether @command{inetd} should wait for the server to exit before
19786 listening to new service requests.
19788 A string containing the user (and, optionally, group) name of the user
19789 as whom the server should run. The group name can be specified in a
19790 suffix, separated by a colon or period, i.e.@: @code{"user"},
19791 @code{"user:group"} or @code{"user.group"}.
19792 @item @code{program} (default: @code{"internal"})
19793 The server program which will serve the requests, or @code{"internal"}
19794 if @command{inetd} should use a built-in service.
19795 @item @code{arguments} (default: @code{'()})
19796 A list strings or file-like objects, which are the server program's
19797 arguments, starting with the zeroth argument, i.e.@: the name of the
19798 program itself. For @command{inetd}'s internal services, this entry
19799 must be @code{'()} or @code{'("internal")}.
19802 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
19803 detailed discussion of each configuration field.
19806 @cindex opendht, distributed hash table network service
19807 @cindex dhtproxy, for use with jami
19808 @defvr {Scheme Variable} opendht-service-type
19809 This is the type of the service running a @uref{https://opendht.net,
19810 OpenDHT} node, @command{dhtnode}. The daemon can be used to host your
19811 own proxy service to the distributed hash table (DHT), for example to
19812 connect to with Jami, among other applications.
19814 @quotation Important
19815 When using the OpenDHT proxy server, the IP addresses it ``sees'' from
19816 the clients should be addresses reachable from other peers. In practice
19817 this means that a publicly reachable address is best suited for a proxy
19818 server, outside of your private network. For example, hosting the proxy
19819 server on a IPv4 private local network and exposing it via port
19820 forwarding could work for external peers, but peers local to the proxy
19821 would have their private addresses shared with the external peers,
19822 leading to connectivity problems.
19825 The value of this service is a @code{opendht-configuration} object, as
19829 @c The fields documentation has been auto-generated using the
19830 @c configuration->documentation procedure from
19831 @c (gnu services configuration).
19832 @deftp {Data Type} opendht-configuration
19833 Available @code{opendht-configuration} fields are:
19836 @item @code{opendht} (default: @code{opendht}) (type: file-like)
19837 The @code{opendht} package to use.
19839 @item @code{peer-discovery?} (default: @code{#f}) (type: boolean)
19840 Whether to enable the multicast local peer discovery mechanism.
19842 @item @code{enable-logging?} (default: @code{#f}) (type: boolean)
19843 Whether to enable logging messages to syslog. It is disabled by default
19844 as it is rather verbose.
19846 @item @code{debug?} (default: @code{#f}) (type: boolean)
19847 Whether to enable debug-level logging messages. This has no effect if
19848 logging is disabled.
19850 @item @code{bootstrap-host} (default: @code{"bootstrap.jami.net:4222"}) (type: maybe-string)
19851 The node host name that is used to make the first connection to the
19852 network. A specific port value can be provided by appending the
19853 @code{:PORT} suffix. By default, it uses the Jami bootstrap nodes, but
19854 any host can be specified here. It's also possible to disable
19855 bootstrapping by explicitly setting this field to the
19856 @code{%unset-value} value.
19858 @item @code{port} (default: @code{4222}) (type: maybe-number)
19859 The UDP port to bind to. When left unspecified, an available port is
19860 automatically selected.
19862 @item @code{proxy-server-port} (type: maybe-number)
19863 Spawn a proxy server listening on the specified port.
19865 @item @code{proxy-server-port-tls} (type: maybe-number)
19866 Spawn a proxy server listening to TLS connections on the specified port.
19872 @defvr {Scheme Variable} tor-service-type
19873 This is the type for a service that runs the @uref{https://torproject.org,
19874 Tor} anonymous networking daemon. The service is configured using a
19875 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
19876 @code{tor} unprivileged user, which is a member of the @code{tor} group.
19880 @deftp {Data Type} tor-configuration
19882 @item @code{tor} (default: @code{tor})
19883 The package that provides the Tor daemon. This package is expected to provide
19884 the daemon at @file{bin/tor} relative to its output directory. The default
19885 package is the @uref{https://www.torproject.org, Tor Project's}
19888 @item @code{config-file} (default: @code{(plain-file "empty" "")})
19889 The configuration file to use. It will be appended to a default configuration
19890 file, and the final configuration file will be passed to @code{tor} via its
19891 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
19892 file-like objects}). See @code{man tor} for details on the configuration file
19895 @item @code{hidden-services} (default: @code{'()})
19896 The list of @code{<hidden-service>} records to use. For any hidden service
19897 you include in this list, appropriate configuration to enable the hidden
19898 service will be automatically added to the default configuration file. You
19899 may conveniently create @code{<hidden-service>} records using the
19900 @code{tor-hidden-service} procedure described below.
19902 @item @code{socks-socket-type} (default: @code{'tcp})
19903 The default socket type that Tor should use for its SOCKS socket. This must
19904 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
19905 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
19906 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
19907 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
19910 If you want to customize the SOCKS socket in more detail, leave
19911 @code{socks-socket-type} at its default value of @code{'tcp} and use
19912 @code{config-file} to override the default by providing your own
19913 @code{SocksPort} option.
19915 @item @code{control-socket?} (default: @code{#f})
19916 Whether or not to provide a ``control socket'' by which Tor can be
19917 controlled to, for instance, dynamically instantiate tor onion services.
19918 If @code{#t}, Tor will listen for control commands on the UNIX domain socket
19919 @file{/var/run/tor/control-sock}, which will be made writable by members of the
19925 @cindex hidden service
19926 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
19927 Define a new Tor @dfn{hidden service} called @var{name} and implementing
19928 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
19931 '((22 "127.0.0.1:22")
19932 (80 "127.0.0.1:8080"))
19935 In this example, port 22 of the hidden service is mapped to local port 22, and
19936 port 80 is mapped to local port 8080.
19938 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
19939 the @file{hostname} file contains the @code{.onion} host name for the hidden
19942 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
19943 project's documentation} for more information.
19946 The @code{(gnu services rsync)} module provides the following services:
19948 You might want an rsync daemon if you have files that you want available
19949 so anyone (or just yourself) can download existing files or upload new
19952 @deffn {Scheme Variable} rsync-service-type
19953 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
19954 The value for this service type is a
19955 @command{rsync-configuration} record as in this example:
19958 ;; Export two directories over rsync. By default rsync listens on
19959 ;; all the network interfaces.
19960 (service rsync-service-type
19961 (rsync-configuration
19962 (modules (list (rsync-module
19964 (file-name "/srv/zik")
19968 (file-name "/home/charlie/movies"))))))
19971 See below for details about @code{rsync-configuration}.
19974 @deftp {Data Type} rsync-configuration
19975 Data type representing the configuration for @code{rsync-service}.
19978 @item @code{package} (default: @var{rsync})
19979 @code{rsync} package to use.
19981 @item @code{address} (default: @code{#f})
19982 IP address on which @command{rsync} listens for incoming connections.
19983 If unspecified, it defaults to listening on all available addresses.
19985 @item @code{port-number} (default: @code{873})
19986 TCP port on which @command{rsync} listens for incoming connections. If port
19987 is less than @code{1024} @command{rsync} needs to be started as the
19988 @code{root} user and group.
19990 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
19991 Name of the file where @command{rsync} writes its PID.
19993 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
19994 Name of the file where @command{rsync} writes its lock file.
19996 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
19997 Name of the file where @command{rsync} writes its log file.
19999 @item @code{user} (default: @code{"root"})
20000 Owner of the @code{rsync} process.
20002 @item @code{group} (default: @code{"root"})
20003 Group of the @code{rsync} process.
20005 @item @code{uid} (default: @code{"rsyncd"})
20006 User name or user ID that file transfers to and from that module should take
20007 place as when the daemon was run as @code{root}.
20009 @item @code{gid} (default: @code{"rsyncd"})
20010 Group name or group ID that will be used when accessing the module.
20012 @item @code{modules} (default: @code{%default-modules})
20013 List of ``modules''---i.e., directories exported over rsync. Each
20014 element must be a @code{rsync-module} record, as described below.
20018 @deftp {Data Type} rsync-module
20019 This is the data type for rsync ``modules''. A module is a directory
20020 exported over the rsync protocol. The available fields are as follows:
20024 The module name. This is the name that shows up in URLs. For example,
20025 if the module is called @code{music}, the corresponding URL will be
20026 @code{rsync://host.example.org/music}.
20028 @item @code{file-name}
20029 Name of the directory being exported.
20031 @item @code{comment} (default: @code{""})
20032 Comment associated with the module. Client user interfaces may display
20033 it when they obtain the list of available modules.
20035 @item @code{read-only?} (default: @code{#t})
20036 Whether or not client will be able to upload files. If this is false,
20037 the uploads will be authorized if permissions on the daemon side permit
20040 @item @code{chroot?} (default: @code{#t})
20041 When this is true, the rsync daemon changes root to the module's
20042 directory before starting file transfers with the client. This improves
20043 security, but requires rsync to run as root.
20045 @item @code{timeout} (default: @code{300})
20046 Idle time in seconds after which the daemon closes a connection with the
20051 The @code{(gnu services syncthing)} module provides the following services:
20054 You might want a syncthing daemon if you have files between two or more
20055 computers and want to sync them in real time, safely protected from
20058 @deffn {Scheme Variable} syncthing-service-type
20059 This is the service type for the @uref{https://syncthing.net/,
20060 syncthing} daemon, The value for this service type is a
20061 @command{syncthing-configuration} record as in this example:
20064 (service syncthing-service-type
20065 (syncthing-configuration (user "alice")))
20068 See below for details about @code{syncthing-configuration}.
20070 @deftp {Data Type} syncthing-configuration
20071 Data type representing the configuration for @code{syncthing-service-type}.
20074 @item @code{syncthing} (default: @var{syncthing})
20075 @code{syncthing} package to use.
20077 @item @code{arguments} (default: @var{'()})
20078 List of command-line arguments passing to @code{syncthing} binary.
20080 @item @code{logflags} (default: @var{0})
20081 Sum of logging flags, see
20082 @uref{https://docs.syncthing.net/users/syncthing.html#cmdoption-logflags, Syncthing documentation logflags}.
20084 @item @code{user} (default: @var{#f})
20085 The user as which the Syncthing service is to be run.
20086 This assumes that the specified user exists.
20088 @item @code{group} (default: @var{"users"})
20089 The group as which the Syncthing service is to be run.
20090 This assumes that the specified group exists.
20092 @item @code{home} (default: @var{#f})
20093 Common configuration and data directory. The default configuration
20094 directory is @file{$HOME} of the specified Syncthing @code{user}.
20100 Furthermore, @code{(gnu services ssh)} provides the following services.
20104 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
20105 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
20106 [#:allow-empty-passwords? #f] [#:root-login? #f] @
20107 [#:syslog-output? #t] [#:x11-forwarding? #t] @
20108 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
20109 [#:public-key-authentication? #t] [#:initialize? #t]
20110 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
20111 @var{host-key} must designate a file containing the host key, and readable
20114 When @var{daemonic?} is true, @command{lshd} will detach from the
20115 controlling terminal and log its output to syslogd, unless one sets
20116 @var{syslog-output?} to false. Obviously, it also makes lsh-service
20117 depend on existence of syslogd service. When @var{pid-file?} is true,
20118 @command{lshd} writes its PID to the file called @var{pid-file}.
20120 When @var{initialize?} is true, automatically create the seed and host key
20121 upon service activation if they do not exist yet. This may take long and
20122 require interaction.
20124 When @var{initialize?} is false, it is up to the user to initialize the
20125 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
20126 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
20127 basics,,, lsh, LSH Manual}).
20129 When @var{interfaces} is empty, lshd listens for connections on all the
20130 network interfaces; otherwise, @var{interfaces} must be a list of host names
20133 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
20134 passwords, and @var{root-login?} specifies whether to accept log-ins as
20137 The other options should be self-descriptive.
20142 @deffn {Scheme Variable} openssh-service-type
20143 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
20144 shell daemon, @command{sshd}. Its value must be an
20145 @code{openssh-configuration} record as in this example:
20148 (service openssh-service-type
20149 (openssh-configuration
20150 (x11-forwarding? #t)
20151 (permit-root-login 'prohibit-password)
20153 `(("alice" ,(local-file "alice.pub"))
20154 ("bob" ,(local-file "bob.pub"))))))
20157 See below for details about @code{openssh-configuration}.
20159 This service can be extended with extra authorized keys, as in this
20163 (service-extension openssh-service-type
20164 (const `(("charlie"
20165 ,(local-file "charlie.pub")))))
20169 @deftp {Data Type} openssh-configuration
20170 This is the configuration record for OpenSSH's @command{sshd}.
20173 @item @code{openssh} (default @var{openssh})
20174 The OpenSSH package to use.
20176 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
20177 Name of the file where @command{sshd} writes its PID.
20179 @item @code{port-number} (default: @code{22})
20180 TCP port on which @command{sshd} listens for incoming connections.
20182 @item @code{max-connections} (default: @code{200})
20183 Hard limit on the maximum number of simultaneous client connections,
20184 enforced by the inetd-style Shepherd service (@pxref{Service De- and
20185 Constructors, @code{make-inetd-constructor},, shepherd, The GNU Shepherd
20188 @item @code{permit-root-login} (default: @code{#f})
20189 This field determines whether and when to allow logins as root. If
20190 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
20191 If it's the symbol @code{'prohibit-password}, then root logins are
20192 permitted but not with password-based authentication.
20194 @item @code{allow-empty-passwords?} (default: @code{#f})
20195 When true, users with empty passwords may log in. When false, they may
20198 @item @code{password-authentication?} (default: @code{#t})
20199 When true, users may log in with their password. When false, they have
20200 other authentication methods.
20202 @item @code{public-key-authentication?} (default: @code{#t})
20203 When true, users may log in using public key authentication. When
20204 false, users have to use other authentication method.
20206 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
20207 This is used only by protocol version 2.
20209 @item @code{x11-forwarding?} (default: @code{#f})
20210 When true, forwarding of X11 graphical client connections is
20211 enabled---in other words, @command{ssh} options @option{-X} and
20212 @option{-Y} will work.
20214 @item @code{allow-agent-forwarding?} (default: @code{#t})
20215 Whether to allow agent forwarding.
20217 @item @code{allow-tcp-forwarding?} (default: @code{#t})
20218 Whether to allow TCP forwarding.
20220 @item @code{gateway-ports?} (default: @code{#f})
20221 Whether to allow gateway ports.
20223 @item @code{challenge-response-authentication?} (default: @code{#f})
20224 Specifies whether challenge response authentication is allowed (e.g.@: via
20227 @item @code{use-pam?} (default: @code{#t})
20228 Enables the Pluggable Authentication Module interface. If set to
20229 @code{#t}, this will enable PAM authentication using
20230 @code{challenge-response-authentication?} and
20231 @code{password-authentication?}, in addition to PAM account and session
20232 module processing for all authentication types.
20234 Because PAM challenge response authentication usually serves an
20235 equivalent role to password authentication, you should disable either
20236 @code{challenge-response-authentication?} or
20237 @code{password-authentication?}.
20239 @item @code{print-last-log?} (default: @code{#t})
20240 Specifies whether @command{sshd} should print the date and time of the
20241 last user login when a user logs in interactively.
20243 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
20244 Configures external subsystems (e.g.@: file transfer daemon).
20246 This is a list of two-element lists, each of which containing the
20247 subsystem name and a command (with optional arguments) to execute upon
20250 The command @command{internal-sftp} implements an in-process SFTP
20251 server. Alternatively, one can specify the @command{sftp-server} command:
20253 (service openssh-service-type
20254 (openssh-configuration
20256 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
20259 @item @code{accepted-environment} (default: @code{'()})
20260 List of strings describing which environment variables may be exported.
20262 Each string gets on its own line. See the @code{AcceptEnv} option in
20263 @code{man sshd_config}.
20265 This example allows ssh-clients to export the @env{COLORTERM} variable.
20266 It is set by terminal emulators, which support colors. You can use it in
20267 your shell's resource file to enable colors for the prompt and commands
20268 if this variable is set.
20271 (service openssh-service-type
20272 (openssh-configuration
20273 (accepted-environment '("COLORTERM"))))
20276 @item @code{authorized-keys} (default: @code{'()})
20277 @cindex authorized keys, SSH
20278 @cindex SSH authorized keys
20279 This is the list of authorized keys. Each element of the list is a user
20280 name followed by one or more file-like objects that represent SSH public
20284 (openssh-configuration
20286 `(("rekado" ,(local-file "rekado.pub"))
20287 ("chris" ,(local-file "chris.pub"))
20288 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
20292 registers the specified public keys for user accounts @code{rekado},
20293 @code{chris}, and @code{root}.
20295 Additional authorized keys can be specified @i{via}
20296 @code{service-extension}.
20298 Note that this does @emph{not} interfere with the use of
20299 @file{~/.ssh/authorized_keys}.
20301 @item @code{generate-host-keys?} (default: @code{#t})
20302 Whether to generate host key pairs with @command{ssh-keygen -A} under
20303 @file{/etc/ssh} if there are none.
20305 Generating key pairs takes a few seconds when enough entropy is
20306 available and is only done once. You might want to turn it off for
20307 instance in a virtual machine that does not need it because host keys
20308 are provided in some other way, and where the extra boot time is a
20311 @item @code{log-level} (default: @code{'info})
20312 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
20313 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
20314 page for @file{sshd_config} for the full list of level names.
20316 @item @code{extra-content} (default: @code{""})
20317 This field can be used to append arbitrary text to the configuration file. It
20318 is especially useful for elaborate configurations that cannot be expressed
20319 otherwise. This configuration, for example, would generally disable root
20320 logins, but permit them from one specific IP address:
20323 (openssh-configuration
20325 Match Address 192.168.0.1
20326 PermitRootLogin yes"))
20332 @deffn {Scheme Procedure} dropbear-service [@var{config}]
20333 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
20334 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
20337 For example, to specify a Dropbear service listening on port 1234, add
20338 this call to the operating system's @code{services} field:
20341 (dropbear-service (dropbear-configuration
20342 (port-number 1234)))
20346 @deftp {Data Type} dropbear-configuration
20347 This data type represents the configuration of a Dropbear SSH daemon.
20350 @item @code{dropbear} (default: @var{dropbear})
20351 The Dropbear package to use.
20353 @item @code{port-number} (default: 22)
20354 The TCP port where the daemon waits for incoming connections.
20356 @item @code{syslog-output?} (default: @code{#t})
20357 Whether to enable syslog output.
20359 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
20360 File name of the daemon's PID file.
20362 @item @code{root-login?} (default: @code{#f})
20363 Whether to allow @code{root} logins.
20365 @item @code{allow-empty-passwords?} (default: @code{#f})
20366 Whether to allow empty passwords.
20368 @item @code{password-authentication?} (default: @code{#t})
20369 Whether to enable password-based authentication.
20374 @deffn {Scheme Variable} autossh-service-type
20375 This is the type for the @uref{https://www.harding.motd.ca/autossh,
20376 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
20377 restarting it as necessary should it die or stop passing traffic.
20378 AutoSSH can be run manually from the command-line by passing arguments
20379 to the binary @command{autossh} from the package @code{autossh}, but it
20380 can also be run as a Guix service. This latter use case is documented
20383 AutoSSH can be used to forward local traffic to a remote machine using
20384 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
20387 For example, to specify a service running autossh as the user
20388 @code{pino} and forwarding all local connections to port @code{8081} to
20389 @code{remote:8081} using an SSH tunnel, add this call to the operating
20390 system's @code{services} field:
20393 (service autossh-service-type
20394 (autossh-configuration
20396 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
20400 @deftp {Data Type} autossh-configuration
20401 This data type represents the configuration of an AutoSSH service.
20405 @item @code{user} (default @code{"autossh"})
20406 The user as which the AutoSSH service is to be run.
20407 This assumes that the specified user exists.
20409 @item @code{poll} (default @code{600})
20410 Specifies the connection poll time in seconds.
20412 @item @code{first-poll} (default @code{#f})
20413 Specifies how many seconds AutoSSH waits before the first connection
20414 test. After this first test, polling is resumed at the pace defined in
20415 @code{poll}. When set to @code{#f}, the first poll is not treated
20416 specially and will also use the connection poll specified in
20419 @item @code{gate-time} (default @code{30})
20420 Specifies how many seconds an SSH connection must be active before it is
20421 considered successful.
20423 @item @code{log-level} (default @code{1})
20424 The log level, corresponding to the levels used by syslog---so @code{0}
20425 is the most silent while @code{7} is the chattiest.
20427 @item @code{max-start} (default @code{#f})
20428 The maximum number of times SSH may be (re)started before AutoSSH exits.
20429 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
20431 @item @code{message} (default @code{""})
20432 The message to append to the echo message sent when testing connections.
20434 @item @code{port} (default @code{"0"})
20435 The ports used for monitoring the connection. When set to @code{"0"},
20436 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
20437 a positive integer, ports @var{n} and @var{n}+1 are used for
20438 monitoring the connection, such that port @var{n} is the base
20439 monitoring port and @code{n+1} is the echo port. When set to
20440 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
20441 integers, the ports @var{n} and @var{m} are used for monitoring the
20442 connection, such that port @var{n} is the base monitoring port and
20443 @var{m} is the echo port.
20445 @item @code{ssh-options} (default @code{'()})
20446 The list of command-line arguments to pass to @command{ssh} when it is
20447 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
20448 may cause undefined behaviour.
20454 @deffn {Scheme Variable} webssh-service-type
20455 This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
20456 program that runs a web SSH client. WebSSH can be run manually from the
20457 command-line by passing arguments to the binary @command{wssh} from the
20458 package @code{webssh}, but it can also be run as a Guix service. This
20459 latter use case is documented here.
20461 For example, to specify a service running WebSSH on loopback interface
20462 on port @code{8888} with reject policy with a list of allowed to
20463 connection hosts, and NGINX as a reverse-proxy to this service listening
20464 for HTTPS connection, add this call to the operating system's
20465 @code{services} field:
20468 (service webssh-service-type
20469 (webssh-configuration (address "127.0.0.1")
20472 (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
20473 "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
20475 (service nginx-service-type
20476 (nginx-configuration
20479 (nginx-server-configuration
20480 (inherit %webssh-configuration-nginx)
20481 (server-name '("webssh.example.com"))
20482 (listen '("443 ssl"))
20483 (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
20484 (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
20486 (cons (nginx-location-configuration
20487 (uri "/.well-known")
20488 (body '("root /var/www;")))
20489 (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
20493 @deftp {Data Type} webssh-configuration
20494 Data type representing the configuration for @code{webssh-service}.
20497 @item @code{package} (default: @var{webssh})
20498 @code{webssh} package to use.
20500 @item @code{user-name} (default: @var{"webssh"})
20501 User name or user ID that file transfers to and from that module should take
20504 @item @code{group-name} (default: @var{"webssh"})
20505 Group name or group ID that will be used when accessing the module.
20507 @item @code{address} (default: @var{#f})
20508 IP address on which @command{webssh} listens for incoming connections.
20510 @item @code{port} (default: @var{8888})
20511 TCP port on which @command{webssh} listens for incoming connections.
20513 @item @code{policy} (default: @var{#f})
20514 Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
20516 @item @code{known-hosts} (default: @var{'()})
20517 List of hosts which allowed for SSH connection from @command{webssh}.
20519 @item @code{log-file} (default: @file{"/var/log/webssh.log"})
20520 Name of the file where @command{webssh} writes its log file.
20522 @item @code{log-level} (default: @var{#f})
20528 @defvr {Scheme Variable} %facebook-host-aliases
20529 This variable contains a string for use in @file{/etc/hosts}
20530 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
20531 line contains a entry that maps a known server name of the Facebook
20532 on-line service---e.g., @code{www.facebook.com}---to the local
20533 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
20535 This variable is typically used in the @code{hosts-file} field of an
20536 @code{operating-system} declaration (@pxref{operating-system Reference,
20537 @file{/etc/hosts}}):
20540 (use-modules (gnu) (guix))
20543 (host-name "mymachine")
20546 ;; Create a /etc/hosts file with aliases for "localhost"
20547 ;; and "mymachine", as well as for Facebook servers.
20548 (plain-file "hosts"
20549 (string-append (local-host-aliases host-name)
20550 %facebook-host-aliases))))
20553 This mechanism can prevent programs running locally, such as Web
20554 browsers, from accessing Facebook.
20557 The @code{(gnu services avahi)} provides the following definition.
20559 @defvr {Scheme Variable} avahi-service-type
20560 This is the service that runs @command{avahi-daemon}, a system-wide
20561 mDNS/DNS-SD responder that allows for service discovery and
20562 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
20563 Its value must be an @code{avahi-configuration} record---see below.
20565 This service extends the name service cache daemon (nscd) so that it can
20566 resolve @code{.local} host names using
20567 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
20568 Service Switch}, for information on host name resolution.
20570 Additionally, add the @var{avahi} package to the system profile so that
20571 commands such as @command{avahi-browse} are directly usable.
20574 @deftp {Data Type} avahi-configuration
20575 Data type representation the configuration for Avahi.
20579 @item @code{host-name} (default: @code{#f})
20580 If different from @code{#f}, use that as the host name to
20581 publish for this machine; otherwise, use the machine's actual host name.
20583 @item @code{publish?} (default: @code{#t})
20584 When true, allow host names and services to be published (broadcast) over the
20587 @item @code{publish-workstation?} (default: @code{#t})
20588 When true, @command{avahi-daemon} publishes the machine's host name and IP
20589 address via mDNS on the local network. To view the host names published on
20590 your local network, you can run:
20593 avahi-browse _workstation._tcp
20596 @item @code{wide-area?} (default: @code{#f})
20597 When true, DNS-SD over unicast DNS is enabled.
20599 @item @code{ipv4?} (default: @code{#t})
20600 @itemx @code{ipv6?} (default: @code{#t})
20601 These fields determine whether to use IPv4/IPv6 sockets.
20603 @item @code{domains-to-browse} (default: @code{'()})
20604 This is a list of domains to browse.
20608 @deffn {Scheme Variable} openvswitch-service-type
20609 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
20610 service, whose value should be an @code{openvswitch-configuration}
20614 @deftp {Data Type} openvswitch-configuration
20615 Data type representing the configuration of Open vSwitch, a multilayer
20616 virtual switch which is designed to enable massive network automation
20617 through programmatic extension.
20620 @item @code{package} (default: @var{openvswitch})
20621 Package object of the Open vSwitch.
20626 @defvr {Scheme Variable} pagekite-service-type
20627 This is the service type for the @uref{https://pagekite.net, PageKite} service,
20628 a tunneling solution for making localhost servers publicly visible, even from
20629 behind restrictive firewalls or NAT without forwarded ports. The value for
20630 this service type is a @code{pagekite-configuration} record.
20632 Here's an example exposing the local HTTP and SSH daemons:
20635 (service pagekite-service-type
20636 (pagekite-configuration
20637 (kites '("http:@@kitename:localhost:80:@@kitesecret"
20638 "raw/22:@@kitename:localhost:22:@@kitesecret"))
20639 (extra-file "/etc/pagekite.rc")))
20643 @deftp {Data Type} pagekite-configuration
20644 Data type representing the configuration of PageKite.
20647 @item @code{package} (default: @var{pagekite})
20648 Package object of PageKite.
20650 @item @code{kitename} (default: @code{#f})
20651 PageKite name for authenticating to the frontend server.
20653 @item @code{kitesecret} (default: @code{#f})
20654 Shared secret for authenticating to the frontend server. You should probably
20655 put this inside @code{extra-file} instead.
20657 @item @code{frontend} (default: @code{#f})
20658 Connect to the named PageKite frontend server instead of the
20659 @uref{https://pagekite.net,,pagekite.net} service.
20661 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
20662 List of service kites to use. Exposes HTTP on port 80 by default. The format
20663 is @code{proto:kitename:host:port:secret}.
20665 @item @code{extra-file} (default: @code{#f})
20666 Extra configuration file to read, which you are expected to create manually.
20667 Use this to add additional options and manage shared secrets out-of-band.
20672 @defvr {Scheme Variable} yggdrasil-service-type
20673 The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
20674 Yggdrasil network}, an early-stage implementation of a fully end-to-end
20675 encrypted IPv6 network.
20678 Yggdrasil provides name-independent routing with cryptographically generated
20679 addresses. Static addressing means you can keep the same address as long as
20680 you want, even if you move to a new location, or generate a new address (by
20681 generating new keys) whenever you want.
20682 @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
20685 Pass it a value of @code{yggdrasil-configuration} to connect it to public
20686 peers and/or local peers.
20688 Here is an example using public peers and a static address. The static
20689 signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
20690 (the default value for @code{config-file}).
20693 ;; part of the operating-system declaration
20694 (service yggdrasil-service-type
20695 (yggdrasil-configuration
20696 (autoconf? #f) ;; use only the public peers
20699 ;; https://github.com/yggdrasil-network/public-peers
20700 '((peers . #("tcp://1.2.3.4:1337"))))
20701 ;; /etc/yggdrasil-private.conf is the default value for config-file
20705 # sample content for /etc/yggdrasil-private.conf
20707 # Your public key. Your peers may ask you for this to put
20708 # into their AllowedPublicKeys configuration.
20709 PublicKey: 64277...
20711 # Your private key. DO NOT share this with anyone!
20712 PrivateKey: 5c750...
20717 @deftp {Data Type} yggdrasil-configuration
20718 Data type representing the configuration of Yggdrasil.
20721 @item @code{package} (default: @code{yggdrasil})
20722 Package object of Yggdrasil.
20724 @item @code{json-config} (default: @code{'()})
20725 Contents of @file{/etc/yggdrasil.conf}. Will be merged with
20726 @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
20727 the Guix store, which is readable to all users. @strong{Do not store your
20728 private keys in it}. See the output of @code{yggdrasil -genconf} for a
20729 quick overview of valid keys and their default values.
20731 @item @code{autoconf?} (default: @code{#f})
20732 Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
20733 and peer with IPv6 neighbors.
20735 @item @code{log-level} (default: @code{'info})
20736 How much detail to include in logs. Use @code{'debug} for more detail.
20738 @item @code{log-to} (default: @code{'stdout})
20739 Where to send logs. By default, the service logs standard output to
20740 @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
20741 sends output to the running syslog service.
20743 @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
20744 What HJSON file to load sensitive data from. This is where private keys
20745 should be stored, which are necessary to specify if you don't want a
20746 randomized address after each restart. Use @code{#f} to disable. Options
20747 defined in this file take precedence over @code{json-config}. Use the output
20748 of @code{yggdrasil -genconf} as a starting point. To configure a static
20749 address, delete everything except these options:
20752 @item @code{EncryptionPublicKey}
20753 @item @code{EncryptionPrivateKey}
20754 @item @code{SigningPublicKey}
20755 @item @code{SigningPrivateKey}
20761 @defvr {Scheme Variable} ipfs-service-type
20762 The service type for connecting to the @uref{https://ipfs.io,IPFS network},
20763 a global, versioned, peer-to-peer file system. Pass it a
20764 @code{ipfs-configuration} to change the ports used for the gateway and API.
20766 Here's an example configuration, using some non-standard ports:
20769 (service ipfs-service-type
20770 (ipfs-configuration
20771 (gateway "/ip4/127.0.0.1/tcp/8880")
20772 (api "/ip4/127.0.0.1/tcp/8881")))
20776 @deftp {Data Type} ipfs-configuration
20777 Data type representing the configuration of IPFS.
20780 @item @code{package} (default: @code{go-ipfs})
20781 Package object of IPFS.
20783 @item @code{gateway} (default: @code{"/ip4/127.0.0.1/tcp/8082"})
20784 Address of the gateway, in ‘multiaddress’ format.
20786 @item @code{api} (default: @code{"/ip4/127.0.0.1/tcp/5001"})
20787 Address of the API endpoint, in ‘multiaddress’ format.
20792 @deffn {Scheme Variable} keepalived-service-type
20793 This is the type for the @uref{https://www.keepalived.org/, Keepalived}
20794 routing software, @command{keepalived}. Its value must be an
20795 @code{keepalived-configuration} record as in this example for master
20799 (service keepalived-service-type
20800 (keepalived-configuration
20801 (config-file (local-file "keepalived-master.conf"))))
20804 where @file{keepalived-master.conf}:
20807 vrrp_instance my-group @{
20810 virtual_router_id 100
20812 unicast_peer @{ 10.0.0.2 @}
20813 virtual_ipaddress @{
20819 and for backup machine:
20822 (service keepalived-service-type
20823 (keepalived-configuration
20824 (config-file (local-file "keepalived-backup.conf"))))
20827 where @file{keepalived-backup.conf}:
20830 vrrp_instance my-group @{
20833 virtual_router_id 100
20835 unicast_peer @{ 10.0.0.3 @}
20836 virtual_ipaddress @{
20843 @node Unattended Upgrades
20844 @subsection Unattended Upgrades
20846 @cindex unattended upgrades
20847 @cindex upgrades, unattended
20848 Guix provides a service to perform @emph{unattended upgrades}:
20849 periodically, the system automatically reconfigures itself from the
20850 latest Guix. Guix System has several properties that make unattended
20855 upgrades are transactional (either the upgrade succeeds or it fails, but
20856 you cannot end up with an ``in-between'' system state);
20858 the upgrade log is kept---you can view it with @command{guix system
20859 list-generations}---and you can roll back to any previous generation,
20860 should the upgraded system fail to behave as intended;
20862 channel code is authenticated so you know you can only run genuine code
20863 (@pxref{Channels});
20865 @command{guix system reconfigure} prevents downgrades, which makes it
20866 immune to @dfn{downgrade attacks}.
20869 To set up unattended upgrades, add an instance of
20870 @code{unattended-upgrade-service-type} like the one below to the list of
20871 your operating system services:
20874 (service unattended-upgrade-service-type)
20877 The defaults above set up weekly upgrades: every Sunday at midnight.
20878 You do not need to provide the operating system configuration file: it
20879 uses @file{/run/current-system/configuration.scm}, which ensures it
20880 always uses your latest configuration---@pxref{provenance-service-type},
20881 for more information about this file.
20883 There are several things that can be configured, in particular the
20884 periodicity and services (daemons) to be restarted upon completion.
20885 When the upgrade is successful, the service takes care of deleting
20886 system generations older that some threshold, as per @command{guix
20887 system delete-generations}. See the reference below for details.
20889 To ensure that upgrades are actually happening, you can run
20890 @command{guix system describe}. To investigate upgrade failures, visit
20891 the unattended upgrade log file (see below).
20893 @defvr {Scheme Variable} unattended-upgrade-service-type
20894 This is the service type for unattended upgrades. It sets up an mcron
20895 job (@pxref{Scheduled Job Execution}) that runs @command{guix system
20896 reconfigure} from the latest version of the specified channels.
20898 Its value must be a @code{unattended-upgrade-configuration} record (see
20902 @deftp {Data Type} unattended-upgrade-configuration
20903 This data type represents the configuration of the unattended upgrade
20904 service. The following fields are available:
20907 @item @code{schedule} (default: @code{"30 01 * * 0"})
20908 This is the schedule of upgrades, expressed as a gexp containing an
20909 mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
20910 mcron, GNU@tie{}mcron}).
20912 @item @code{channels} (default: @code{#~%default-channels})
20913 This gexp specifies the channels to use for the upgrade
20914 (@pxref{Channels}). By default, the tip of the official @code{guix}
20917 @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
20918 This field specifies the operating system configuration file to use.
20919 The default is to reuse the config file of the current configuration.
20921 There are cases, though, where referring to
20922 @file{/run/current-system/configuration.scm} is not enough, for instance
20923 because that file refers to extra files (SSH public keys, extra
20924 configuration files, etc.) @i{via} @code{local-file} and similar
20925 constructs. For those cases, we recommend something along these lines:
20928 (unattended-upgrade-configuration
20929 (operating-system-file
20930 (file-append (local-file "." "config-dir" #:recursive? #t)
20934 The effect here is to import all of the current directory into the
20935 store, and to refer to @file{config.scm} within that directory.
20936 Therefore, uses of @code{local-file} within @file{config.scm} will work
20937 as expected. @xref{G-Expressions}, for information about
20938 @code{local-file} and @code{file-append}.
20940 @item @code{services-to-restart} (default: @code{'(mcron)})
20941 This field specifies the Shepherd services to restart when the upgrade
20944 Those services are restarted right away upon completion, as with
20945 @command{herd restart}, which ensures that the latest version is
20946 running---remember that by default @command{guix system reconfigure}
20947 only restarts services that are not currently running, which is
20948 conservative: it minimizes disruption but leaves outdated services
20951 Use @command{herd status} to find out candidates for restarting.
20952 @xref{Services}, for general information about services. Common
20953 services to restart would include @code{ntpd} and @code{ssh-daemon}.
20955 By default, the @code{mcron} service is restarted. This ensures that
20956 the latest version of the unattended upgrade job will be used next time.
20958 @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
20959 This is the expiration time in seconds for system generations. System
20960 generations older that this amount of time are deleted with
20961 @command{guix system delete-generations} when an upgrade completes.
20964 The unattended upgrade service does not run the garbage collector. You
20965 will probably want to set up your own mcron job to run @command{guix gc}
20969 @item @code{maximum-duration} (default: @code{3600})
20970 Maximum duration in seconds for the upgrade; past that time, the upgrade
20973 This is primarily useful to ensure the upgrade does not end up
20974 rebuilding or re-downloading ``the world''.
20976 @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
20977 File where unattended upgrades are logged.
20982 @subsection X Window
20985 @cindex X Window System
20986 @cindex login manager
20987 Support for the X Window graphical display system---specifically
20988 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
20989 there is no @code{xorg-service} procedure. Instead, the X server is
20990 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
20993 @cindex GNOME, login manager
20994 GDM of course allows users to log in into window managers and desktop
20995 environments other than GNOME; for those using GNOME, GDM is required for
20996 features such as automatic screen locking.
20998 @cindex window manager
20999 To use X11, you must install at least one @dfn{window manager}---for
21000 example the @code{windowmaker} or @code{openbox} packages---preferably
21001 by adding it to the @code{packages} field of your operating system
21002 definition (@pxref{operating-system Reference, system-wide packages}).
21004 @anchor{wayland-gdm}
21005 GDM also supports Wayland: it can itself use Wayland instead of X11 for
21006 its user interface, and it can also start Wayland sessions. The former is
21007 required for the latter, to enable, set @code{wayland?} to @code{#t} in
21008 @code{gdm-configuration}.
21010 @defvr {Scheme Variable} gdm-service-type
21011 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
21012 Desktop Manager} (GDM), a program that manages graphical display servers and
21013 handles graphical user logins. Its value must be a @code{gdm-configuration}
21016 @cindex session types
21017 GDM looks for @dfn{session types} described by the @file{.desktop} files in
21018 @file{/run/current-system/profile/share/xsessions} (for X11 sessions) and
21019 @file{/run/current-system/profile/share/wayland-sessions} (for Wayland
21020 sessions) and allows users to choose a session from the log-in screen.
21021 Packages such as @code{gnome}, @code{xfce}, @code{i3} and @code{sway} provide
21022 @file{.desktop} files; adding them to the system-wide set of packages
21023 automatically makes them available at the log-in screen.
21025 In addition, @file{~/.xsession} files are honored. When available,
21026 @file{~/.xsession} must be an executable that starts a window manager
21027 and/or other X clients.
21030 @deftp {Data Type} gdm-configuration
21032 @item @code{auto-login?} (default: @code{#f})
21033 @itemx @code{default-user} (default: @code{#f})
21034 When @code{auto-login?} is false, GDM presents a log-in screen.
21036 When @code{auto-login?} is true, GDM logs in directly as
21037 @code{default-user}.
21039 @item @code{debug?} (default: @code{#f})
21040 When true, GDM writes debug messages to its log.
21042 @item @code{gnome-shell-assets} (default: ...)
21043 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
21045 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
21046 Configuration of the Xorg graphical server.
21048 @item @code{x-session} (default: @code{(xinitrc)})
21049 Script to run before starting a X session.
21051 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
21052 File name of the @code{dbus-daemon} executable.
21054 @item @code{gdm} (default: @code{gdm})
21055 The GDM package to use.
21057 @item @code{wayland?} (default: @code{#f})
21058 When true, enables Wayland in GDM, necessary to use Wayland sessions.
21060 @item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
21061 The Wayland session wrapper to use, needed to setup the
21066 @defvr {Scheme Variable} slim-service-type
21067 This is the type for the SLiM graphical login manager for X11.
21069 Like GDM, SLiM looks for session types described by @file{.desktop} files and
21070 allows users to choose a session from the log-in screen using @kbd{F1}. It
21071 also honors @file{~/.xsession} files.
21073 Unlike GDM, SLiM does not spawn the user session on a different VT after
21074 logging in, which means that you can only start one graphical session. If you
21075 want to be able to run multiple graphical sessions at the same time you have
21076 to add multiple SLiM services to your system services. The following example
21077 shows how to replace the default GDM service with two SLiM services on tty7
21081 (use-modules (gnu services)
21082 (gnu services desktop)
21083 (gnu services xorg))
21087 (services (cons* (service slim-service-type (slim-configuration
21090 (service slim-service-type (slim-configuration
21093 (modify-services %desktop-services
21094 (delete gdm-service-type)))))
21099 @deftp {Data Type} slim-configuration
21100 Data type representing the configuration of @code{slim-service-type}.
21103 @item @code{allow-empty-passwords?} (default: @code{#t})
21104 Whether to allow logins with empty passwords.
21106 @item @code{gnupg?} (default: @code{#f})
21107 If enabled, @code{pam-gnupg} will attempt to automatically unlock the
21108 user's GPG keys with the login password via @code{gpg-agent}. The
21109 keygrips of all keys to be unlocked should be written to
21110 @file{~/.pam-gnupg}, and can be queried with @code{gpg -K
21111 --with-keygrip}. Presetting passphrases must be enabled by adding
21112 @code{allow-preset-passphrase} in @file{~/.gnupg/gpg-agent.conf}.
21114 @item @code{auto-login?} (default: @code{#f})
21115 @itemx @code{default-user} (default: @code{""})
21116 When @code{auto-login?} is false, SLiM presents a log-in screen.
21118 When @code{auto-login?} is true, SLiM logs in directly as
21119 @code{default-user}.
21121 @item @code{theme} (default: @code{%default-slim-theme})
21122 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
21123 The graphical theme to use and its name.
21125 @item @code{auto-login-session} (default: @code{#f})
21126 If true, this must be the name of the executable to start as the default
21127 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
21129 If false, a session described by one of the available @file{.desktop}
21130 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
21134 You must install at least one window manager in the system profile or in
21135 your user profile. Failing to do that, if @code{auto-login-session} is
21136 false, you will be unable to log in.
21139 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
21140 Configuration of the Xorg graphical server.
21142 @item @code{display} (default @code{":0"})
21143 The display on which to start the Xorg graphical server.
21145 @item @code{vt} (default @code{"vt7"})
21146 The VT on which to start the Xorg graphical server.
21148 @item @code{xauth} (default: @code{xauth})
21149 The XAuth package to use.
21151 @item @code{shepherd} (default: @code{shepherd})
21152 The Shepherd package used when invoking @command{halt} and
21155 @item @code{sessreg} (default: @code{sessreg})
21156 The sessreg package used in order to register the session.
21158 @item @code{slim} (default: @code{slim})
21159 The SLiM package to use.
21163 @defvr {Scheme Variable} %default-theme
21164 @defvrx {Scheme Variable} %default-theme-name
21165 The default SLiM theme and its name.
21169 @cindex login manager
21171 @defvr {Scheme Variable} sddm-service-type
21172 This is the type of the service to run the
21173 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
21174 must be a @code{sddm-configuration} record (see below).
21176 Here's an example use:
21179 (service sddm-service-type
21180 (sddm-configuration
21181 (auto-login-user "alice")
21182 (auto-login-session "xfce.desktop")))
21186 @deftp {Data Type} sddm-configuration
21187 This data type represents the configuration of the SDDM login manager.
21188 The available fields are:
21191 @item @code{sddm} (default: @code{sddm})
21192 The SDDM package to use.
21194 @item @code{display-server} (default: "x11")
21195 Select display server to use for the greeter. Valid values are
21196 @samp{"x11"} or @samp{"wayland"}.
21198 @item @code{numlock} (default: "on")
21199 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
21201 @item @code{halt-command} (default @code{#~(string-append #$shepherd "/sbin/halt")})
21202 Command to run when halting.
21204 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
21205 Command to run when rebooting.
21207 @item @code{theme} (default "maldives")
21208 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
21209 @samp{"maldives"} or @samp{"maya"}.
21211 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
21212 Directory to look for themes.
21214 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
21215 Directory to look for faces.
21217 @item @code{default-path} (default "/run/current-system/profile/bin")
21218 Default PATH to use.
21220 @item @code{minimum-uid} (default: 1000)
21221 Minimum UID displayed in SDDM and allowed for log-in.
21223 @item @code{maximum-uid} (default: 2000)
21224 Maximum UID to display in SDDM.
21226 @item @code{remember-last-user?} (default #t)
21227 Remember last user.
21229 @item @code{remember-last-session?} (default #t)
21230 Remember last session.
21232 @item @code{hide-users} (default "")
21233 Usernames to hide from SDDM greeter.
21235 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
21236 Users with shells listed will be hidden from the SDDM greeter.
21238 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
21239 Script to run before starting a wayland session.
21241 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
21242 Directory to look for desktop files starting wayland sessions.
21244 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
21245 Configuration of the Xorg graphical server.
21247 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
21250 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
21253 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
21254 Script to run after starting xorg-server.
21256 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
21257 Script to run before stopping xorg-server.
21259 @item @code{xsession-command} (default: @code{xinitrc})
21260 Script to run before starting a X session.
21262 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
21263 Directory to look for desktop files starting X sessions.
21265 @item @code{minimum-vt} (default: 7)
21268 @item @code{auto-login-user} (default "")
21269 User account that will be automatically logged in.
21270 Setting this to the empty string disables auto-login.
21272 @item @code{auto-login-session} (default "")
21273 The @file{.desktop} file name to use as the auto-login session, or the empty string.
21275 @item @code{relogin?} (default #f)
21276 Relogin after logout.
21282 @cindex Xorg, configuration
21283 @deftp {Data Type} xorg-configuration
21284 This data type represents the configuration of the Xorg graphical display
21285 server. Note that there is no Xorg service; instead, the X server is started
21286 by a ``display manager'' such as GDM, SDDM, and SLiM@. Thus, the configuration
21287 of these display managers aggregates an @code{xorg-configuration} record.
21290 @item @code{modules} (default: @code{%default-xorg-modules})
21291 This is a list of @dfn{module packages} loaded by the Xorg
21292 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
21294 @item @code{fonts} (default: @code{%default-xorg-fonts})
21295 This is a list of font directories to add to the server's @dfn{font path}.
21297 @item @code{drivers} (default: @code{'()})
21298 This must be either the empty list, in which case Xorg chooses a graphics
21299 driver automatically, or a list of driver names that will be tried in this
21300 order---e.g., @code{("modesetting" "vesa")}.
21302 @item @code{resolutions} (default: @code{'()})
21303 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
21304 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
21307 @cindex keyboard layout, for Xorg
21308 @cindex keymap, for Xorg
21309 @item @code{keyboard-layout} (default: @code{#f})
21310 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
21311 English (``qwerty'') for a 105-key PC keyboard.
21313 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
21314 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
21315 information on how to specify the keyboard layout.
21317 @item @code{extra-config} (default: @code{'()})
21318 This is a list of strings or objects appended to the configuration file. It
21319 is used to pass extra text to be added verbatim to the configuration file.
21321 @item @code{server} (default: @code{xorg-server})
21322 This is the package providing the Xorg server.
21324 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
21325 This is the list of command-line arguments to pass to the X server. The
21326 default is @code{-nolisten tcp}.
21330 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
21331 [@var{login-manager-service-type}]
21332 Tell the log-in manager (of type @var{login-manager-service-type}) to use
21333 @var{config}, an @code{<xorg-configuration>} record.
21335 Since the Xorg configuration is embedded in the log-in manager's
21336 configuration---e.g., @code{gdm-configuration}---this procedure provides a
21337 shorthand to set the Xorg configuration.
21340 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
21341 Return a @code{startx} script in which the modules, fonts, etc. specified
21342 in @var{config}, are available. The result should be used in place of
21345 Usually the X server is started by a login manager.
21349 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
21350 Add @var{package}, a package for a screen locker or screen saver whose
21351 command is @var{program}, to the set of setuid programs and add a PAM entry
21352 for it. For example:
21355 (screen-locker-service xlockmore "xlock")
21358 makes the good ol' XlockMore usable.
21362 @node Printing Services
21363 @subsection Printing Services
21365 @cindex printer support with CUPS
21366 The @code{(gnu services cups)} module provides a Guix service definition
21367 for the CUPS printing service. To add printer support to a Guix
21368 system, add a @code{cups-service} to the operating system definition:
21370 @deffn {Scheme Variable} cups-service-type
21371 The service type for the CUPS print server. Its value should be a valid
21372 CUPS configuration (see below). To use the default settings, simply
21375 (service cups-service-type)
21379 The CUPS configuration controls the basic things about your CUPS
21380 installation: what interfaces it listens on, what to do if a print job
21381 fails, how much logging to do, and so on. To actually add a printer,
21382 you have to visit the @url{http://localhost:631} URL, or use a tool such
21383 as GNOME's printer configuration services. By default, configuring a
21384 CUPS service will generate a self-signed certificate if needed, for
21385 secure connections to the print server.
21387 Suppose you want to enable the Web interface of CUPS and also add
21388 support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
21389 package and for HP printers @i{via} the @code{hplip-minimal} package.
21390 You can do that directly, like this (you need to use the
21391 @code{(gnu packages cups)} module):
21394 (service cups-service-type
21395 (cups-configuration
21396 (web-interface? #t)
21398 (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
21402 If you wish to use the Qt5 based GUI which comes with the hplip
21403 package then it is suggested that you install the @code{hplip} package,
21404 either in your OS configuration file or as your user.
21407 The available configuration parameters follow. Each parameter
21408 definition is preceded by its type; for example, @samp{string-list foo}
21409 indicates that the @code{foo} parameter should be specified as a list of
21410 strings. There is also a way to specify the configuration as a string,
21411 if you have an old @code{cupsd.conf} file that you want to port over
21412 from some other system; see the end for more details.
21414 @c The following documentation was initially generated by
21415 @c (generate-documentation) in (gnu services cups). Manually maintained
21416 @c documentation is better, so we shouldn't hesitate to edit below as
21417 @c needed. However if the change you want to make to this documentation
21418 @c can be done in an automated way, it's probably easier to change
21419 @c (generate-documentation) than to make it below and have to deal with
21420 @c the churn as CUPS updates.
21423 Available @code{cups-configuration} fields are:
21425 @deftypevr {@code{cups-configuration} parameter} package cups
21429 @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list brlaser cups-filters epson-inkjet-printer-escpr foomatic-filters hplip-minimal splix)})
21430 Drivers and other extensions to the CUPS package.
21433 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
21434 Configuration of where to write logs, what directories to use for print
21435 spools, and related privileged configuration parameters.
21437 Available @code{files-configuration} fields are:
21439 @deftypevr {@code{files-configuration} parameter} log-location access-log
21440 Defines the access log filename. Specifying a blank filename disables
21441 access log generation. The value @code{stderr} causes log entries to be
21442 sent to the standard error file when the scheduler is running in the
21443 foreground, or to the system log daemon when run in the background. The
21444 value @code{syslog} causes log entries to be sent to the system log
21445 daemon. The server name may be included in filenames using the string
21446 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
21448 Defaults to @samp{"/var/log/cups/access_log"}.
21451 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
21452 Where CUPS should cache data.
21454 Defaults to @samp{"/var/cache/cups"}.
21457 @deftypevr {@code{files-configuration} parameter} string config-file-perm
21458 Specifies the permissions for all configuration files that the scheduler
21461 Note that the permissions for the printers.conf file are currently
21462 masked to only allow access from the scheduler user (typically root).
21463 This is done because printer device URIs sometimes contain sensitive
21464 authentication information that should not be generally known on the
21465 system. There is no way to disable this security feature.
21467 Defaults to @samp{"0640"}.
21470 @deftypevr {@code{files-configuration} parameter} log-location error-log
21471 Defines the error log filename. Specifying a blank filename disables
21472 error log generation. The value @code{stderr} causes log entries to be
21473 sent to the standard error file when the scheduler is running in the
21474 foreground, or to the system log daemon when run in the background. The
21475 value @code{syslog} causes log entries to be sent to the system log
21476 daemon. The server name may be included in filenames using the string
21477 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
21479 Defaults to @samp{"/var/log/cups/error_log"}.
21482 @deftypevr {@code{files-configuration} parameter} string fatal-errors
21483 Specifies which errors are fatal, causing the scheduler to exit. The
21488 No errors are fatal.
21491 All of the errors below are fatal.
21494 Browsing initialization errors are fatal, for example failed connections
21495 to the DNS-SD daemon.
21498 Configuration file syntax errors are fatal.
21501 Listen or Port errors are fatal, except for IPv6 failures on the
21502 loopback or @code{any} addresses.
21505 Log file creation or write errors are fatal.
21508 Bad startup file permissions are fatal, for example shared TLS
21509 certificate and key files with world-read permissions.
21512 Defaults to @samp{"all -browse"}.
21515 @deftypevr {@code{files-configuration} parameter} boolean file-device?
21516 Specifies whether the file pseudo-device can be used for new printer
21517 queues. The URI @uref{file:///dev/null} is always allowed.
21519 Defaults to @samp{#f}.
21522 @deftypevr {@code{files-configuration} parameter} string group
21523 Specifies the group name or ID that will be used when executing external
21526 Defaults to @samp{"lp"}.
21529 @deftypevr {@code{files-configuration} parameter} string log-file-group
21530 Specifies the group name or ID that will be used for log files.
21532 Defaults to @samp{"lpadmin"}.
21535 @deftypevr {@code{files-configuration} parameter} string log-file-perm
21536 Specifies the permissions for all log files that the scheduler writes.
21538 Defaults to @samp{"0644"}.
21541 @deftypevr {@code{files-configuration} parameter} log-location page-log
21542 Defines the page log filename. Specifying a blank filename disables
21543 page log generation. The value @code{stderr} causes log entries to be
21544 sent to the standard error file when the scheduler is running in the
21545 foreground, or to the system log daemon when run in the background. The
21546 value @code{syslog} causes log entries to be sent to the system log
21547 daemon. The server name may be included in filenames using the string
21548 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
21550 Defaults to @samp{"/var/log/cups/page_log"}.
21553 @deftypevr {@code{files-configuration} parameter} string remote-root
21554 Specifies the username that is associated with unauthenticated accesses
21555 by clients claiming to be the root user. The default is @code{remroot}.
21557 Defaults to @samp{"remroot"}.
21560 @deftypevr {@code{files-configuration} parameter} file-name request-root
21561 Specifies the directory that contains print jobs and other HTTP request
21564 Defaults to @samp{"/var/spool/cups"}.
21567 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
21568 Specifies the level of security sandboxing that is applied to print
21569 filters, backends, and other child processes of the scheduler; either
21570 @code{relaxed} or @code{strict}. This directive is currently only
21571 used/supported on macOS.
21573 Defaults to @samp{strict}.
21576 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
21577 Specifies the location of TLS certificates and private keys. CUPS will
21578 look for public and private keys in this directory: @file{.crt} files
21579 for PEM-encoded certificates and corresponding @file{.key} files for
21580 PEM-encoded private keys.
21582 Defaults to @samp{"/etc/cups/ssl"}.
21585 @deftypevr {@code{files-configuration} parameter} file-name server-root
21586 Specifies the directory containing the server configuration files.
21588 Defaults to @samp{"/etc/cups"}.
21591 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
21592 Specifies whether the scheduler calls fsync(2) after writing
21593 configuration or state files.
21595 Defaults to @samp{#f}.
21598 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
21599 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
21602 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
21603 Specifies the directory where temporary files are stored.
21605 Defaults to @samp{"/var/spool/cups/tmp"}.
21608 @deftypevr {@code{files-configuration} parameter} string user
21609 Specifies the user name or ID that is used when running external
21612 Defaults to @samp{"lp"}.
21615 @deftypevr {@code{files-configuration} parameter} string set-env
21616 Set the specified environment variable to be passed to child processes.
21618 Defaults to @samp{"variable value"}.
21622 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
21623 Specifies the logging level for the AccessLog file. The @code{config}
21624 level logs when printers and classes are added, deleted, or modified and
21625 when configuration files are accessed or updated. The @code{actions}
21626 level logs when print jobs are submitted, held, released, modified, or
21627 canceled, and any of the conditions for @code{config}. The @code{all}
21628 level logs all requests.
21630 Defaults to @samp{actions}.
21633 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
21634 Specifies whether to purge job history data automatically when it is no
21635 longer required for quotas.
21637 Defaults to @samp{#f}.
21640 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
21641 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
21642 For example, @samp{"_cups" "_print"} will tell network clients that both
21643 CUPS sharing and IPP Everywhere are supported.
21645 Defaults to @samp{"_cups"}.
21648 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
21649 Specifies which protocols to use for local printer sharing.
21651 Defaults to @samp{dnssd}.
21654 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
21655 Specifies whether the CUPS web interface is advertised.
21657 Defaults to @samp{#f}.
21660 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
21661 Specifies whether shared printers are advertised.
21663 Defaults to @samp{#f}.
21666 @deftypevr {@code{cups-configuration} parameter} string classification
21667 Specifies the security classification of the server. Any valid banner
21668 name can be used, including @samp{"classified"}, @samp{"confidential"},
21669 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
21670 banner can be omitted to disable secure printing functions.
21672 Defaults to @samp{""}.
21675 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
21676 Specifies whether users may override the classification (cover page) of
21677 individual print jobs using the @code{job-sheets} option.
21679 Defaults to @samp{#f}.
21682 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
21683 Specifies the default type of authentication to use.
21685 Defaults to @samp{Basic}.
21688 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
21689 Specifies whether encryption will be used for authenticated requests.
21691 Defaults to @samp{Required}.
21694 @deftypevr {@code{cups-configuration} parameter} string default-language
21695 Specifies the default language to use for text and web content.
21697 Defaults to @samp{"en"}.
21700 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
21701 Specifies the default paper size for new print queues. @samp{"Auto"}
21702 uses a locale-specific default, while @samp{"None"} specifies there is
21703 no default paper size. Specific size names are typically
21704 @samp{"Letter"} or @samp{"A4"}.
21706 Defaults to @samp{"Auto"}.
21709 @deftypevr {@code{cups-configuration} parameter} string default-policy
21710 Specifies the default access policy to use.
21712 Defaults to @samp{"default"}.
21715 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
21716 Specifies whether local printers are shared by default.
21718 Defaults to @samp{#t}.
21721 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
21722 Specifies the delay for updating of configuration and state files, in
21723 seconds. A value of 0 causes the update to happen as soon as possible,
21724 typically within a few milliseconds.
21726 Defaults to @samp{30}.
21729 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
21730 Specifies what to do when an error occurs. Possible values are
21731 @code{abort-job}, which will discard the failed print job;
21732 @code{retry-job}, which will retry the job at a later time;
21733 @code{retry-current-job}, which retries the failed job immediately; and
21734 @code{stop-printer}, which stops the printer.
21736 Defaults to @samp{stop-printer}.
21739 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
21740 Specifies the maximum cost of filters that are run concurrently, which
21741 can be used to minimize disk, memory, and CPU resource problems. A
21742 limit of 0 disables filter limiting. An average print to a
21743 non-PostScript printer needs a filter limit of about 200. A PostScript
21744 printer needs about half that (100). Setting the limit below these
21745 thresholds will effectively limit the scheduler to printing a single job
21748 Defaults to @samp{0}.
21751 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
21752 Specifies the scheduling priority of filters that are run to print a
21753 job. The nice value ranges from 0, the highest priority, to 19, the
21756 Defaults to @samp{0}.
21759 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
21760 Specifies whether to do reverse lookups on connecting clients. The
21761 @code{double} setting causes @code{cupsd} to verify that the hostname
21762 resolved from the address matches one of the addresses returned for that
21763 hostname. Double lookups also prevent clients with unregistered
21764 addresses from connecting to your server. Only set this option to
21765 @code{#t} or @code{double} if absolutely required.
21767 Defaults to @samp{#f}.
21770 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
21771 Specifies the number of seconds to wait before killing the filters and
21772 backend associated with a canceled or held job.
21774 Defaults to @samp{30}.
21777 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
21778 Specifies the interval between retries of jobs in seconds. This is
21779 typically used for fax queues but can also be used with normal print
21780 queues whose error policy is @code{retry-job} or
21781 @code{retry-current-job}.
21783 Defaults to @samp{30}.
21786 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
21787 Specifies the number of retries that are done for jobs. This is
21788 typically used for fax queues but can also be used with normal print
21789 queues whose error policy is @code{retry-job} or
21790 @code{retry-current-job}.
21792 Defaults to @samp{5}.
21795 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
21796 Specifies whether to support HTTP keep-alive connections.
21798 Defaults to @samp{#t}.
21801 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
21802 Specifies the maximum size of print files, IPP requests, and HTML form
21803 data. A limit of 0 disables the limit check.
21805 Defaults to @samp{0}.
21808 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
21809 Listens on the specified interfaces for connections. Valid values are
21810 of the form @var{address}:@var{port}, where @var{address} is either an
21811 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
21812 indicate all addresses. Values can also be file names of local UNIX
21813 domain sockets. The Listen directive is similar to the Port directive
21814 but allows you to restrict access to specific interfaces or networks.
21817 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
21818 Specifies the number of pending connections that will be allowed. This
21819 normally only affects very busy servers that have reached the MaxClients
21820 limit, but can also be triggered by large numbers of simultaneous
21821 connections. When the limit is reached, the operating system will
21822 refuse additional connections until the scheduler can accept the pending
21825 Defaults to @samp{128}.
21828 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
21829 Specifies a set of additional access controls.
21831 Available @code{location-access-controls} fields are:
21833 @deftypevr {@code{location-access-controls} parameter} file-name path
21834 Specifies the URI path to which the access control applies.
21837 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
21838 Access controls for all access to this path, in the same format as the
21839 @code{access-controls} of @code{operation-access-control}.
21841 Defaults to @samp{()}.
21844 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
21845 Access controls for method-specific access to this path.
21847 Defaults to @samp{()}.
21849 Available @code{method-access-controls} fields are:
21851 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
21852 If @code{#t}, apply access controls to all methods except the listed
21853 methods. Otherwise apply to only the listed methods.
21855 Defaults to @samp{#f}.
21858 @deftypevr {@code{method-access-controls} parameter} method-list methods
21859 Methods to which this access control applies.
21861 Defaults to @samp{()}.
21864 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
21865 Access control directives, as a list of strings. Each string should be
21866 one directive, such as @samp{"Order allow,deny"}.
21868 Defaults to @samp{()}.
21873 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
21874 Specifies the number of debugging messages that are retained for logging
21875 if an error occurs in a print job. Debug messages are logged regardless
21876 of the LogLevel setting.
21878 Defaults to @samp{100}.
21881 @deftypevr {@code{cups-configuration} parameter} log-level log-level
21882 Specifies the level of logging for the ErrorLog file. The value
21883 @code{none} stops all logging while @code{debug2} logs everything.
21885 Defaults to @samp{info}.
21888 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
21889 Specifies the format of the date and time in the log files. The value
21890 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
21892 Defaults to @samp{standard}.
21895 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
21896 Specifies the maximum number of simultaneous clients that are allowed by
21899 Defaults to @samp{100}.
21902 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
21903 Specifies the maximum number of simultaneous clients that are allowed
21904 from a single address.
21906 Defaults to @samp{100}.
21909 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
21910 Specifies the maximum number of copies that a user can print of each
21913 Defaults to @samp{9999}.
21916 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
21917 Specifies the maximum time a job may remain in the @code{indefinite}
21918 hold state before it is canceled. A value of 0 disables cancellation of
21921 Defaults to @samp{0}.
21924 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
21925 Specifies the maximum number of simultaneous jobs that are allowed. Set
21926 to 0 to allow an unlimited number of jobs.
21928 Defaults to @samp{500}.
21931 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
21932 Specifies the maximum number of simultaneous jobs that are allowed per
21933 printer. A value of 0 allows up to MaxJobs jobs per printer.
21935 Defaults to @samp{0}.
21938 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
21939 Specifies the maximum number of simultaneous jobs that are allowed per
21940 user. A value of 0 allows up to MaxJobs jobs per user.
21942 Defaults to @samp{0}.
21945 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
21946 Specifies the maximum time a job may take to print before it is
21947 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
21949 Defaults to @samp{10800}.
21952 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
21953 Specifies the maximum size of the log files before they are rotated, in
21954 bytes. The value 0 disables log rotation.
21956 Defaults to @samp{1048576}.
21959 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
21960 Specifies the maximum amount of time to allow between files in a
21961 multiple file print job, in seconds.
21963 Defaults to @samp{900}.
21966 @deftypevr {@code{cups-configuration} parameter} string page-log-format
21967 Specifies the format of PageLog lines. Sequences beginning with percent
21968 (@samp{%}) characters are replaced with the corresponding information,
21969 while all other characters are copied literally. The following percent
21970 sequences are recognized:
21974 insert a single percent character
21977 insert the value of the specified IPP attribute
21980 insert the number of copies for the current page
21983 insert the current page number
21986 insert the current date and time in common log format
21992 insert the printer name
21995 insert the username
21998 A value of the empty string disables page logging. The string @code{%p
21999 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
22000 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
22003 Defaults to @samp{""}.
22006 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
22007 Passes the specified environment variable(s) to child processes; a list
22010 Defaults to @samp{()}.
22013 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
22014 Specifies named access control policies.
22016 Available @code{policy-configuration} fields are:
22018 @deftypevr {@code{policy-configuration} parameter} string name
22019 Name of the policy.
22022 @deftypevr {@code{policy-configuration} parameter} string job-private-access
22023 Specifies an access list for a job's private values. @code{@@ACL} maps
22024 to the printer's requesting-user-name-allowed or
22025 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
22026 owner. @code{@@SYSTEM} maps to the groups listed for the
22027 @code{system-group} field of the @code{files-configuration},
22028 which is reified into the @code{cups-files.conf(5)} file. Other
22029 possible elements of the access list include specific user names, and
22030 @code{@@@var{group}} to indicate members of a specific group. The
22031 access list may also be simply @code{all} or @code{default}.
22033 Defaults to @samp{"@@OWNER @@SYSTEM"}.
22036 @deftypevr {@code{policy-configuration} parameter} string job-private-values
22037 Specifies the list of job values to make private, or @code{all},
22038 @code{default}, or @code{none}.
22040 Defaults to @samp{"job-name job-originating-host-name
22041 job-originating-user-name phone"}.
22044 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
22045 Specifies an access list for a subscription's private values.
22046 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
22047 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
22048 owner. @code{@@SYSTEM} maps to the groups listed for the
22049 @code{system-group} field of the @code{files-configuration},
22050 which is reified into the @code{cups-files.conf(5)} file. Other
22051 possible elements of the access list include specific user names, and
22052 @code{@@@var{group}} to indicate members of a specific group. The
22053 access list may also be simply @code{all} or @code{default}.
22055 Defaults to @samp{"@@OWNER @@SYSTEM"}.
22058 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
22059 Specifies the list of job values to make private, or @code{all},
22060 @code{default}, or @code{none}.
22062 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
22063 notify-subscriber-user-name notify-user-data"}.
22066 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
22067 Access control by IPP operation.
22069 Defaults to @samp{()}.
22073 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
22074 Specifies whether job files (documents) are preserved after a job is
22075 printed. If a numeric value is specified, job files are preserved for
22076 the indicated number of seconds after printing. Otherwise a boolean
22077 value applies indefinitely.
22079 Defaults to @samp{86400}.
22082 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
22083 Specifies whether the job history is preserved after a job is printed.
22084 If a numeric value is specified, the job history is preserved for the
22085 indicated number of seconds after printing. If @code{#t}, the job
22086 history is preserved until the MaxJobs limit is reached.
22088 Defaults to @samp{#t}.
22091 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
22092 Specifies the amount of time to wait for job completion before
22093 restarting the scheduler.
22095 Defaults to @samp{30}.
22098 @deftypevr {@code{cups-configuration} parameter} string rip-cache
22099 Specifies the maximum amount of memory to use when converting documents
22100 into bitmaps for a printer.
22102 Defaults to @samp{"128m"}.
22105 @deftypevr {@code{cups-configuration} parameter} string server-admin
22106 Specifies the email address of the server administrator.
22108 Defaults to @samp{"root@@localhost.localdomain"}.
22111 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
22112 The ServerAlias directive is used for HTTP Host header validation when
22113 clients connect to the scheduler from external interfaces. Using the
22114 special name @code{*} can expose your system to known browser-based DNS
22115 rebinding attacks, even when accessing sites through a firewall. If the
22116 auto-discovery of alternate names does not work, we recommend listing
22117 each alternate name with a ServerAlias directive instead of using
22120 Defaults to @samp{*}.
22123 @deftypevr {@code{cups-configuration} parameter} string server-name
22124 Specifies the fully-qualified host name of the server.
22126 Defaults to @samp{"localhost"}.
22129 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
22130 Specifies what information is included in the Server header of HTTP
22131 responses. @code{None} disables the Server header. @code{ProductOnly}
22132 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
22133 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
22134 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
22135 the output of the @code{uname} command. @code{Full} reports @code{CUPS
22136 2.0.0 (@var{uname}) IPP/2.0}.
22138 Defaults to @samp{Minimal}.
22141 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
22142 Listens on the specified interfaces for encrypted connections. Valid
22143 values are of the form @var{address}:@var{port}, where @var{address} is
22144 either an IPv6 address enclosed in brackets, an IPv4 address, or
22145 @code{*} to indicate all addresses.
22147 Defaults to @samp{()}.
22150 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
22151 Sets encryption options. By default, CUPS only supports encryption
22152 using TLS v1.0 or higher using known secure cipher suites. Security is
22153 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
22154 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
22155 suites, which are required for some older clients. The @code{AllowSSL3} option
22156 enables SSL v3.0, which is required for some older clients that do not support
22157 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
22158 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
22159 protocol version to TLS v1.1.
22161 Defaults to @samp{()}.
22164 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
22165 Specifies whether the scheduler requires clients to strictly adhere to
22166 the IPP specifications.
22168 Defaults to @samp{#f}.
22171 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
22172 Specifies the HTTP request timeout, in seconds.
22174 Defaults to @samp{900}.
22178 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
22179 Specifies whether the web interface is enabled.
22181 Defaults to @samp{#f}.
22184 At this point you're probably thinking ``oh dear, Guix manual, I like
22185 you but you can stop already with the configuration options''. Indeed.
22186 However, one more point: it could be that you have an existing
22187 @code{cupsd.conf} that you want to use. In that case, you can pass an
22188 @code{opaque-cups-configuration} as the configuration of a
22189 @code{cups-service-type}.
22191 Available @code{opaque-cups-configuration} fields are:
22193 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
22197 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
22198 The contents of the @code{cupsd.conf}, as a string.
22201 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
22202 The contents of the @code{cups-files.conf} file, as a string.
22205 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
22206 strings of the same name, you could instantiate a CUPS service like
22210 (service cups-service-type
22211 (opaque-cups-configuration
22212 (cupsd.conf cupsd.conf)
22213 (cups-files.conf cups-files.conf)))
22217 @node Desktop Services
22218 @subsection Desktop Services
22220 The @code{(gnu services desktop)} module provides services that are
22221 usually useful in the context of a ``desktop'' setup---that is, on a
22222 machine running a graphical display server, possibly with graphical user
22223 interfaces, etc. It also defines services that provide specific desktop
22224 environments like GNOME, Xfce or MATE.
22226 To simplify things, the module defines a variable containing the set of
22227 services that users typically expect on a machine with a graphical
22228 environment and networking:
22230 @defvr {Scheme Variable} %desktop-services
22231 This is a list of services that builds upon @code{%base-services} and
22232 adds or adjusts services for a typical ``desktop'' setup.
22234 In particular, it adds a graphical login manager (@pxref{X Window,
22235 @code{gdm-service-type}}), screen lockers, a network management tool
22236 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
22237 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
22238 energy and color management services, the @code{elogind} login and seat
22239 manager, the Polkit privilege service, the GeoClue location service, the
22240 AccountsService daemon that allows authorized users change system passwords,
22241 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
22242 name service switch service configured to be able to use @code{nss-mdns}
22243 (@pxref{Name Service Switch, mDNS}).
22246 The @code{%desktop-services} variable can be used as the @code{services}
22247 field of an @code{operating-system} declaration (@pxref{operating-system
22248 Reference, @code{services}}).
22250 Additionally, the @code{gnome-desktop-service-type},
22251 @code{xfce-desktop-service}, @code{mate-desktop-service-type},
22252 @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
22253 procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
22254 ``add GNOME'' means that system-level services like the backlight adjustment
22255 helpers and the power management utilities are added to the system, extending
22256 @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
22257 elevated privileges on a limited number of special-purpose system interfaces.
22258 Additionally, adding a service made by @code{gnome-desktop-service-type} adds
22259 the GNOME metapackage to the system profile. Likewise, adding the Xfce
22260 service not only adds the @code{xfce} metapackage to the system profile, but
22261 it also gives the Thunar file manager the ability to open a ``root-mode'' file
22262 management window, if the user authenticates using the administrator's
22263 password via the standard polkit graphical interface. To ``add MATE'' means
22264 that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
22265 to operate with elevated privileges on a limited number of special-purpose
22266 system interfaces. Additionally, adding a service of type
22267 @code{mate-desktop-service-type} adds the MATE metapackage to the system
22268 profile. ``Adding Enlightenment'' means that @code{dbus} is extended
22269 appropriately, and several of Enlightenment's binaries are set as setuid,
22270 allowing Enlightenment's screen locker and other functionality to work as
22273 The desktop environments in Guix use the Xorg display server by
22274 default. If you'd like to use the newer display server protocol
22275 called Wayland, you need to enable Wayland support in GDM
22276 (@pxref{wayland-gdm}). Another solution is to use the
22277 @code{sddm-service} instead of GDM as the graphical login manager.
22278 You should then select the ``GNOME (Wayland)'' session in SDDM@.
22279 Alternatively you can also try starting GNOME on Wayland manually from a
22280 TTY with the command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
22281 gnome-session``. Currently only GNOME has support for Wayland.
22283 @defvr {Scheme Variable} gnome-desktop-service-type
22284 This is the type of the service that adds the @uref{https://www.gnome.org,
22285 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
22286 object (see below).
22288 This service adds the @code{gnome} package to the system profile, and extends
22289 polkit with the actions from @code{gnome-settings-daemon}.
22292 @deftp {Data Type} gnome-desktop-configuration
22293 Configuration record for the GNOME desktop environment.
22296 @item @code{gnome} (default: @code{gnome})
22297 The GNOME package to use.
22301 @defvr {Scheme Variable} xfce-desktop-service-type
22302 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
22303 desktop environment. Its value is an @code{xfce-desktop-configuration} object
22306 This service adds the @code{xfce} package to the system profile, and
22307 extends polkit with the ability for @code{thunar} to manipulate the file
22308 system as root from within a user session, after the user has authenticated
22309 with the administrator's password.
22311 Note that @code{xfce4-panel} and its plugin packages should be installed in
22312 the same profile to ensure compatibility. When using this service, you should
22313 add extra plugins (@code{xfce4-whiskermenu-plugin},
22314 @code{xfce4-weather-plugin}, etc.) to the @code{packages} field of your
22315 @code{operating-system}.
22318 @deftp {Data Type} xfce-desktop-configuration
22319 Configuration record for the Xfce desktop environment.
22322 @item @code{xfce} (default: @code{xfce})
22323 The Xfce package to use.
22327 @deffn {Scheme Variable} mate-desktop-service-type
22328 This is the type of the service that runs the @uref{https://mate-desktop.org/,
22329 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
22330 object (see below).
22332 This service adds the @code{mate} package to the system
22333 profile, and extends polkit with the actions from
22334 @code{mate-settings-daemon}.
22337 @deftp {Data Type} mate-desktop-configuration
22338 Configuration record for the MATE desktop environment.
22341 @item @code{mate} (default: @code{mate})
22342 The MATE package to use.
22346 @deffn {Scheme Variable} lxqt-desktop-service-type
22347 This is the type of the service that runs the @uref{https://lxqt-project.org,
22348 LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
22349 object (see below).
22351 This service adds the @code{lxqt} package to the system
22355 @deftp {Data Type} lxqt-desktop-configuration
22356 Configuration record for the LXQt desktop environment.
22359 @item @code{lxqt} (default: @code{lxqt})
22360 The LXQT package to use.
22364 @deffn {Scheme Variable} enlightenment-desktop-service-type
22365 Return a service that adds the @code{enlightenment} package to the system
22366 profile, and extends dbus with actions from @code{efl}.
22369 @deftp {Data Type} enlightenment-desktop-service-configuration
22371 @item @code{enlightenment} (default: @code{enlightenment})
22372 The enlightenment package to use.
22376 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
22377 the default @code{%desktop-services} variable doesn't include any of
22378 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
22379 @code{%desktop-services} in the @code{services} field of your
22380 @code{operating-system}:
22383 (use-modules (gnu))
22384 (use-service-modules desktop)
22387 ;; cons* adds items to the list given as its last argument.
22388 (services (cons* (service gnome-desktop-service-type)
22389 (service xfce-desktop-service)
22390 %desktop-services))
22394 These desktop environments will then be available as options in the
22395 graphical login window.
22397 The actual service definitions included in @code{%desktop-services} and
22398 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
22399 are described below.
22401 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()] @
22403 Return a service that runs the ``system bus'', using @var{dbus}, with
22404 support for @var{services}. When @var{verbose?} is true, it causes the
22405 @samp{DBUS_VERBOSE} environment variable to be set to @samp{1}; a
22406 verbose-enabled D-Bus package such as @code{dbus-verbose} should be
22407 provided as @var{dbus} in this scenario. The verbose output is logged
22408 to @file{/var/log/dbus-daemon.log}.
22410 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
22411 facility. Its system bus is used to allow system services to communicate
22412 and to be notified of system-wide events.
22414 @var{services} must be a list of packages that provide an
22415 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
22416 and policy files. For example, to allow avahi-daemon to use the system bus,
22417 @var{services} must be equal to @code{(list avahi)}.
22420 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
22421 Return a service that runs the @code{elogind} login and
22422 seat management daemon. @uref{https://github.com/elogind/elogind,
22423 Elogind} exposes a D-Bus interface that can be used to know which users
22424 are logged in, know what kind of sessions they have open, suspend the
22425 system, inhibit system suspend, reboot the system, and other tasks.
22427 Elogind handles most system-level power events for a computer, for
22428 example suspending the system when a lid is closed, or shutting it down
22429 when the power button is pressed.
22431 The @var{config} keyword argument specifies the configuration for
22432 elogind, and should be the result of an @code{(elogind-configuration
22433 (@var{parameter} @var{value})...)} invocation. Available parameters and
22434 their default values are:
22437 @item kill-user-processes?
22439 @item kill-only-users
22441 @item kill-exclude-users
22443 @item inhibit-delay-max-seconds
22445 @item handle-power-key
22447 @item handle-suspend-key
22449 @item handle-hibernate-key
22451 @item handle-lid-switch
22453 @item handle-lid-switch-docked
22455 @item handle-lid-switch-external-power
22456 @code{*unspecified*}
22457 @item power-key-ignore-inhibited?
22459 @item suspend-key-ignore-inhibited?
22461 @item hibernate-key-ignore-inhibited?
22463 @item lid-switch-ignore-inhibited?
22465 @item holdoff-timeout-seconds
22469 @item idle-action-seconds
22471 @item runtime-directory-size-percent
22473 @item runtime-directory-size
22477 @item suspend-state
22478 @code{("mem" "standby" "freeze")}
22481 @item hibernate-state
22483 @item hibernate-mode
22484 @code{("platform" "shutdown")}
22485 @item hybrid-sleep-state
22487 @item hybrid-sleep-mode
22488 @code{("suspend" "platform" "shutdown")}
22492 @deffn {Scheme Procedure} accountsservice-service @
22493 [#:accountsservice @var{accountsservice}]
22494 Return a service that runs AccountsService, a system service that can
22495 list available accounts, change their passwords, and so on.
22496 AccountsService integrates with PolicyKit to enable unprivileged users
22497 to acquire the capability to modify their system configuration.
22498 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
22499 accountsservice web site} for more information.
22501 The @var{accountsservice} keyword argument is the @code{accountsservice}
22502 package to expose as a service.
22505 @deffn {Scheme Procedure} polkit-service @
22506 [#:polkit @var{polkit}]
22507 Return a service that runs the
22508 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
22509 management service}, which allows system administrators to grant access to
22510 privileged operations in a structured way. By querying the Polkit service, a
22511 privileged system component can know when it should grant additional
22512 capabilities to ordinary users. For example, an ordinary user can be granted
22513 the capability to suspend the system if the user is logged in locally.
22516 @defvr {Scheme Variable} polkit-wheel-service
22517 Service that adds the @code{wheel} group as admins to the Polkit
22518 service. This makes it so that users in the @code{wheel} group are queried
22519 for their own passwords when performing administrative actions instead of
22520 @code{root}'s, similar to the behaviour used by @code{sudo}.
22523 @defvr {Scheme Variable} upower-service-type
22524 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
22525 system-wide monitor for power consumption and battery levels, with the given
22526 configuration settings.
22528 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
22529 notably used by GNOME.
22532 @deftp {Data Type} upower-configuration
22533 Data type representation the configuration for UPower.
22537 @item @code{upower} (default: @var{upower})
22538 Package to use for @code{upower}.
22540 @item @code{watts-up-pro?} (default: @code{#f})
22541 Enable the Watts Up Pro device.
22543 @item @code{poll-batteries?} (default: @code{#t})
22544 Enable polling the kernel for battery level changes.
22546 @item @code{ignore-lid?} (default: @code{#f})
22547 Ignore the lid state, this can be useful if it's incorrect on a device.
22549 @item @code{use-percentage-for-policy?} (default: @code{#f})
22550 Whether battery percentage based policy should be used. The default is to use
22551 the time left, change to @code{#t} to use the percentage.
22553 @item @code{percentage-low} (default: @code{10})
22554 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22555 at which the battery is considered low.
22557 @item @code{percentage-critical} (default: @code{3})
22558 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22559 at which the battery is considered critical.
22561 @item @code{percentage-action} (default: @code{2})
22562 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22563 at which action will be taken.
22565 @item @code{time-low} (default: @code{1200})
22566 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22567 seconds at which the battery is considered low.
22569 @item @code{time-critical} (default: @code{300})
22570 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22571 seconds at which the battery is considered critical.
22573 @item @code{time-action} (default: @code{120})
22574 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22575 seconds at which action will be taken.
22577 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
22578 The action taken when @code{percentage-action} or @code{time-action} is
22579 reached (depending on the configuration of @code{use-percentage-for-policy?}).
22581 Possible values are:
22591 @code{'hybrid-sleep}.
22597 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
22598 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
22599 UDisks}, a @dfn{disk management} daemon that provides user interfaces
22600 with notifications and ways to mount/unmount disks. Programs that talk
22601 to UDisks include the @command{udisksctl} command, part of UDisks, and
22602 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
22603 it will only be able to use the file-system utilities installed in the
22604 system profile. For example if you want to be able to mount NTFS
22605 file-systems in read and write fashion, you'll need to have
22606 @code{ntfs-3g} installed system-wide.
22609 @deffn {Scheme Variable} colord-service-type
22610 This is the type of the service that runs @command{colord}, a system
22611 service with a D-Bus
22612 interface to manage the color profiles of input and output devices such as
22613 screens and scanners. It is notably used by the GNOME Color Manager graphical
22614 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
22615 site} for more information.
22618 @cindex scanner access
22619 @defvr {Scheme Variable} sane-service-type
22620 This service provides access to scanners @i{via}
22621 @uref{http://www.sane-project.org, SANE} by installing the necessary
22622 udev rules. It is included in @code{%desktop-services} (@pxref{Desktop
22623 Services}) and relies by default on @code{sane-backends-minimal} package
22624 (see below) for hardware support.
22627 @defvr {Scheme Variable} sane-backends-minimal
22628 The default package which the @code{sane-service-type} installs. It
22629 supports many recent scanners.
22632 @defvr {Scheme Variable} sane-backends
22633 This package includes support for all scanners that
22634 @code{sane-backends-minimal} supports, plus older Hewlett-Packard
22635 scanners supported by @code{hplip} package. In order to use this on
22636 a system which relies on @code{%desktop-services}, you may use
22637 @code{modify-services} (@pxref{Service Reference,
22638 @code{modify-services}}) as illustrated below:
22641 (use-modules (gnu))
22642 (use-service-modules
22645 (use-package-modules
22649 (define %my-desktop-services
22650 ;; List of desktop services that supports a broader range of scanners.
22651 (modify-services %desktop-services
22652 (sane-service-type _ => sane-backends)))
22656 (services %my-desktop-services))
22660 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
22661 Return a configuration allowing an application to access GeoClue
22662 location data. @var{name} is the Desktop ID of the application, without
22663 the @code{.desktop} part. If @var{allowed?} is true, the application
22664 will have access to location information by default. The boolean
22665 @var{system?} value indicates whether an application is a system component
22666 or not. Finally @var{users} is a list of UIDs of all users for which
22667 this application is allowed location info access. An empty users list
22668 means that all users are allowed.
22671 @defvr {Scheme Variable} %standard-geoclue-applications
22672 The standard list of well-known GeoClue application configurations,
22673 granting authority to the GNOME date-and-time utility to ask for the
22674 current location in order to set the time zone, and allowing the
22675 IceCat and Epiphany web browsers to request location information.
22676 IceCat and Epiphany both query the user before allowing a web page to
22677 know the user's location.
22680 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
22681 [#:whitelist '()] @
22682 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
22683 [#:submit-data? #f]
22684 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
22685 [#:submission-nick "geoclue"] @
22686 [#:applications %standard-geoclue-applications]
22687 Return a service that runs the GeoClue location service. This service
22688 provides a D-Bus interface to allow applications to request access to a
22689 user's physical location, and optionally to add information to online
22690 location databases. See
22691 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
22692 web site} for more information.
22695 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
22696 [@w{#:auto-enable? #f}]
22697 Return a service that runs the @command{bluetoothd} daemon, which
22698 manages all the Bluetooth devices and provides a number of D-Bus
22699 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
22700 powered automatically at boot, which can be useful when using a
22701 bluetooth keyboard or mouse.
22703 Users need to be in the @code{lp} group to access the D-Bus service.
22706 @deffn {Scheme Variable} bluetooth-service-type
22707 This is the type for the @uref{https://bluez.org/, Linux Bluetooth Protocol
22708 Stack} (BlueZ) system, which generates the @file{/etc/bluetooth/main.conf}
22709 configuration file. The value for this type is a @command{bluetooth-configuration}
22710 record as in this example:
22713 (service bluetooth-service-type)
22716 See below for details about @code{bluetooth-configuration}.
22719 @deftp {Data Type} bluetooth-configuration
22720 Data type representing the configuration for @code{bluetooth-service}.
22723 @item @code{bluez} (default: @code{bluez})
22724 @code{bluez} package to use.
22726 @item @code{name} (default: @code{"BlueZ"})
22727 Default adapter name.
22729 @item @code{class} (default: @code{#x000000})
22730 Default device class. Only the major and minor device class bits are considered.
22732 @item @code{discoverable-timeout} (default: @code{180})
22733 How long to stay in discoverable mode before going back to non-discoverable. The
22734 value is in seconds.
22736 @item @code{always-pairable?} (default: @code{#f})
22737 Always allow pairing even if there are no agents registered.
22739 @item @code{pairable-timeout} (default: @code{0})
22740 How long to stay in pairable mode before going back to non-discoverable. The
22741 value is in seconds.
22743 @item @code{device-id} (default: @code{#f})
22744 Use vendor id source (assigner), vendor, product and version information for
22745 DID profile support. The values are separated by ":" and @var{assigner}, @var{VID},
22746 @var{PID} and @var{version}.
22748 Possible values are:
22752 @code{#f} to disable it,
22755 @code{"assigner:1234:5678:abcd"}, where @var{assigner} is either @code{usb} (default)
22756 or @code{bluetooth}.
22760 @item @code{reverse-service-discovery?} (default: @code{#t})
22761 Do reverse service discovery for previously unknown devices that connect to
22762 us. For BR/EDR this option is really only needed for qualification since the
22763 BITE tester doesn't like us doing reverse SDP for some test cases, for LE
22764 this disables the GATT client functionally so it can be used in system which
22765 can only operate as peripheral.
22767 @item @code{name-resolving?} (default: @code{#t})
22768 Enable name resolving after inquiry. Set it to @code{#f} if you don't need
22769 remote devices name and want shorter discovery cycle.
22771 @item @code{debug-keys?} (default: @code{#f})
22772 Enable runtime persistency of debug link keys. Default is false which makes
22773 debug link keys valid only for the duration of the connection that they were
22776 @item @code{controller-mode} (default: @code{'dual})
22777 Restricts all controllers to the specified transport. @code{'dual} means both
22778 BR/EDR and LE are enabled (if supported by the hardware).
22780 Possible values are:
22794 @item @code{multi-profile} (default: @code{'off})
22795 Enables Multi Profile Specification support. This allows to specify if system
22796 supports only Multiple Profiles Single Device (MPSD) configuration or both
22797 Multiple Profiles Single Device (MPSD) and Multiple Profiles Multiple Devices
22798 (MPMD) configurations.
22800 Possible values are:
22814 @item @code{fast-connectable?} (default: @code{#f})
22815 Permanently enables the Fast Connectable setting for adapters that support
22816 it. When enabled other devices can connect faster to us, however the
22817 tradeoff is increased power consumptions. This feature will fully work only
22818 on kernel version 4.1 and newer.
22820 @item @code{privacy} (default: @code{'off})
22821 Default privacy settings.
22825 @code{'off}: Disable local privacy
22828 @code{'network/on}: A device will only accept advertising packets from peer
22829 devices that contain private addresses. It may not be compatible with some
22830 legacy devices since it requires the use of RPA(s) all the time
22833 @code{'device}: A device in device privacy mode is only concerned about the
22834 privacy of the device and will accept advertising packets from peer devices
22835 that contain their Identity Address as well as ones that contain a private
22836 address, even if the peer device has distributed its IRK in the past
22840 and additionally, if @var{controller-mode} is set to @code{'dual}:
22844 @code{'limited-network}: Apply Limited Discoverable Mode to advertising, which
22845 follows the same policy as to BR/EDR that publishes the identity address when
22846 discoverable, and Network Privacy Mode for scanning
22849 @code{'limited-device}: Apply Limited Discoverable Mode to advertising, which
22850 follows the same policy as to BR/EDR that publishes the identity address when
22851 discoverable, and Device Privacy Mode for scanning.
22855 @item @code{just-works-repairing} (default: @code{'never})
22856 Specify the policy to the JUST-WORKS repairing initiated by peer.
22871 @item @code{temporary-timeout} (default: @code{30})
22872 How long to keep temporary devices around. The value is in seconds. @code{0}
22873 disables the timer completely.
22875 @item @code{refresh-discovery?} (default: @code{#t})
22876 Enables the device to issue an SDP request to update known services when
22877 profile is connected.
22879 @item @code{experimental} (default: @code{#f})
22880 Enables experimental features and interfaces, alternatively a list of UUIDs
22893 @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
22896 List of possible UUIDs:
22899 @code{d4992530-b9ec-469f-ab01-6c481c47da1c}: BlueZ Experimental Debug,
22902 @code{671b10b5-42c0-4696-9227-eb28d1b049d6}: BlueZ Experimental Simultaneous Central and Peripheral,
22905 @code{"15c0a148-c273-11ea-b3de-0242ac130004}: BlueZ Experimental LL privacy,
22908 @code{330859bc-7506-492d-9370-9a6f0614037f}: BlueZ Experimental Bluetooth Quality Report,
22911 @code{a6695ace-ee7f-4fb9-881a-5fac66c629af}: BlueZ Experimental Offload Codecs.
22914 @item @code{remote-name-request-retry-delay} (default: @code{300})
22915 The duration to avoid retrying to resolve a peer's name, if the previous
22918 @item @code{page-scan-type} (default: @code{#f})
22919 BR/EDR Page scan activity type.
22921 @item @code{page-scan-interval} (default: @code{#f})
22922 BR/EDR Page scan activity interval.
22924 @item @code{page-scan-window} (default: @code{#f})
22925 BR/EDR Page scan activity window.
22927 @item @code{inquiry-scan-type} (default: @code{#f})
22928 BR/EDR Inquiry scan activity type.
22930 @item @code{inquiry-scan-interval} (default: @code{#f})
22931 BR/EDR Inquiry scan activity interval.
22933 @item @code{inquiry-scan-window} (default: @code{#f})
22934 BR/EDR Inquiry scan activity window.
22936 @item @code{link-supervision-timeout} (default: @code{#f})
22937 BR/EDR Link supervision timeout.
22939 @item @code{page-timeout} (default: @code{#f})
22940 BR/EDR Page timeout.
22942 @item @code{min-sniff-interval} (default: @code{#f})
22943 BR/EDR minimum sniff interval.
22945 @item @code{max-sniff-interval} (default: @code{#f})
22946 BR/EDR maximum sniff interval.
22948 @item @code{min-advertisement-interval} (default: @code{#f})
22949 LE minimum advertisement interval (used for legacy advertisement only).
22951 @item @code{max-advertisement-interval} (default: @code{#f})
22952 LE maximum advertisement interval (used for legacy advertisement only).
22954 @item @code{multi-advertisement-rotation-interval} (default: @code{#f})
22955 LE multiple advertisement rotation interval.
22957 @item @code{scan-interval-auto-connect} (default: @code{#f})
22958 LE scanning interval used for passive scanning supporting auto connect.
22960 @item @code{scan-window-auto-connect} (default: @code{#f})
22961 LE scanning window used for passive scanning supporting auto connect.
22963 @item @code{scan-interval-suspend} (default: @code{#f})
22964 LE scanning interval used for active scanning supporting wake from suspend.
22966 @item @code{scan-window-suspend} (default: @code{#f})
22967 LE scanning window used for active scanning supporting wake from suspend.
22969 @item @code{scan-interval-discovery} (default: @code{#f})
22970 LE scanning interval used for active scanning supporting discovery.
22972 @item @code{scan-window-discovery} (default: @code{#f})
22973 LE scanning window used for active scanning supporting discovery.
22975 @item @code{scan-interval-adv-monitor} (default: @code{#f})
22976 LE scanning interval used for passive scanning supporting the advertisement monitor APIs.
22978 @item @code{scan-window-adv-monitor} (default: @code{#f})
22979 LE scanning window used for passive scanning supporting the advertisement monitor APIs.
22981 @item @code{scan-interval-connect} (default: @code{#f})
22982 LE scanning interval used for connection establishment.
22984 @item @code{scan-window-connect} (default: @code{#f})
22985 LE scanning window used for connection establishment.
22987 @item @code{min-connection-interval} (default: @code{#f})
22988 LE default minimum connection interval. This value is superseded by any specific
22989 value provided via the Load Connection Parameters interface.
22991 @item @code{max-connection-interval} (default: @code{#f})
22992 LE default maximum connection interval. This value is superseded by any specific
22993 value provided via the Load Connection Parameters interface.
22995 @item @code{connection-latency} (default: @code{#f})
22996 LE default connection latency. This value is superseded by any specific
22997 value provided via the Load Connection Parameters interface.
22999 @item @code{connection-supervision-timeout} (default: @code{#f})
23000 LE default connection supervision timeout. This value is superseded by any specific
23001 value provided via the Load Connection Parameters interface.
23003 @item @code{autoconnect-timeout} (default: @code{#f})
23004 LE default autoconnect timeout. This value is superseded by any specific
23005 value provided via the Load Connection Parameters interface.
23007 @item @code{adv-mon-allowlist-scan-duration} (default: @code{300})
23008 Allowlist scan duration during interleaving scan. Only used when scanning for ADV
23009 monitors. The units are msec.
23011 @item @code{adv-mon-no-filter-scan-duration} (default: @code{500})
23012 No filter scan duration during interleaving scan. Only used when scanning for ADV
23013 monitors. The units are msec.
23015 @item @code{enable-adv-mon-interleave-scan?} (default: @code{#t})
23016 Enable/Disable Advertisement Monitor interleave scan for power saving.
23018 @item @code{cache} (default: @code{'always})
23019 GATT attribute cache.
23021 Possible values are:
23024 @code{'always}: Always cache attributes even for devices not paired, this is
23025 recommended as it is best for interoperability, with more consistent
23026 reconnection times and enables proper tracking of notifications for all
23030 @code{'yes}: Only cache attributes of paired devices
23033 @code{'no}: Never cache attributes.
23036 @item @code{key-size} (default: @code{0})
23037 Minimum required Encryption Key Size for accessing secured characteristics.
23039 Possible values are:
23042 @code{0}: Don't care
23045 @code{7 <= N <= 16}
23048 @item @code{exchange-mtu} (default: @code{517})
23049 Exchange MTU size. Possible values are:
23053 @code{23 <= N <= 517}
23056 @item @code{att-channels} (default: @code{3})
23057 Number of ATT channels. Possible values are:
23061 @code{1}: Disables EATT
23067 @item @code{session-mode} (default: @code{'basic})
23068 AVDTP L2CAP signalling channel mode.
23070 Possible values are:
23074 @code{'basic}: Use L2CAP basic mode
23077 @code{'ertm}: Use L2CAP enhanced retransmission mode.
23080 @item @code{stream-mode} (default: @code{'basic})
23081 AVDTP L2CAP transport channel mode.
23083 Possible values are:
23087 @code{'basic}: Use L2CAP basic mode
23090 @code{'streaming}: Use L2CAP streaming mode.
23093 @item @code{reconnect-uuids} (default: @code{'()})
23094 The ReconnectUUIDs defines the set of remote services that should try
23095 to be reconnected to in case of a link loss (link supervision
23096 timeout). The policy plugin should contain a sane set of values by
23097 default, but this list can be overridden here. By setting the list to
23098 empty the reconnection feature gets disabled.
23107 @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
23110 @item @code{reconnect-attempts} (default: @code{7})
23111 Defines the number of attempts to reconnect after a link lost. Setting
23112 the value to 0 disables reconnecting feature.
23114 @item @code{reconnect-intervals} (default: @code{'(1 2 4 8 16 32 64)})
23115 Defines a list of intervals in seconds to use in between attempts. If
23116 the number of attempts defined in @var{reconnect-attempts} is bigger than
23117 the list of intervals the last interval is repeated until the last attempt.
23119 @item @code{auto-enable?} (default: @code{#f})
23120 Defines option to enable all controllers when they are found. This includes
23121 adapters present on start as well as adapters that are plugged in later on.
23123 @item @code{resume-delay} (default: @code{2})
23124 Audio devices that were disconnected due to suspend will be reconnected on
23125 resume. @var{resume-delay} determines the delay between when the controller
23126 resumes from suspend and a connection attempt is made. A longer delay is
23127 better for better co-existence with Wi-Fi. The value is in seconds.
23129 @item @code{rssi-sampling-period} (default: @code{#xFF})
23130 Default RSSI Sampling Period. This is used when a client registers an
23131 advertisement monitor and leaves the RSSISamplingPeriod unset.
23133 Possible values are:
23136 @code{#x0}: Report all advertisements
23139 @code{N = #xXX}: Report advertisements every N x 100 msec (range: #x01 to #xFE)
23142 @code{#xFF}: Report only one advertisement per device during monitoring period.
23148 @defvr {Scheme Variable} gnome-keyring-service-type
23149 This is the type of the service that adds the
23150 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
23151 value is a @code{gnome-keyring-configuration} object (see below).
23153 This service adds the @code{gnome-keyring} package to the system profile
23154 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
23155 a user's login keyring when they log in or setting its password with passwd.
23158 @deftp {Data Type} gnome-keyring-configuration
23159 Configuration record for the GNOME Keyring service.
23162 @item @code{keyring} (default: @code{gnome-keyring})
23163 The GNOME keyring package to use.
23165 @item @code{pam-services}
23166 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
23167 services to extend, where @var{service} is the name of an existing
23168 service to extend and @var{kind} is one of @code{login} or
23171 If @code{login} is given, it adds an optional
23172 @code{pam_gnome_keyring.so} to the auth block without arguments and to
23173 the session block with @code{auto_start}. If @code{passwd} is given, it
23174 adds an optional @code{pam_gnome_keyring.so} to the password block
23177 By default, this field contains ``gdm-password'' with the value @code{login}
23178 and ``passwd'' is with the value @code{passwd}.
23182 @defvr {Scheme Variable} seatd-service-type
23183 @uref{https://sr.ht/~kennylevinsen/seatd/, seatd} is a minimal seat
23186 Seat management takes care of mediating access to shared devices (graphics,
23187 input), without requiring the applications needing access to be root.
23192 ;; make sure seatd is running
23193 (service seatd-service-type))
23195 ;; normally one would want %base-services
23200 @code{seatd} operates over a UNIX domain socket, with @code{libseat}
23201 providing the client side of the protocol. Applications that acquire
23202 access to the shared resources via @code{seatd} (e.g. @code{sway})
23203 need to be able to talk to this socket.
23204 This can be achieved by adding the user they run under to the group
23205 owning @code{seatd}'s socket (usually ``seat''), like so:
23211 (supplementary-groups '("wheel" ; allow use of sudo, etc.
23212 "seat" ; seat management
23213 "audio" ; sound card
23214 "video" ; video devices such as webcams
23215 "cdrom")) ; the good ol' CD-ROM
23216 (comment "Bob's sister"))
23219 Depending on your setup, you will have to not only add regular users,
23220 but also system users to this group. For instance, some greetd greeters
23221 require graphics and therefore also need to negotiate with seatd.
23225 @deftp {Data Type} seatd-configuration
23226 Configuration record for the seatd daemon service.
23229 @item @code{seatd} (default: @code{seatd})
23230 The seatd package to use.
23232 @item @code{group} (default: @samp{"seat"})
23233 Group to own the seatd socket.
23235 @item @code{socket} (default: @samp{"/run/seatd.sock"})
23236 Where to create the seatd socket.
23238 @item @code{logfile} (default: @samp{"/var/log/seatd.log"})
23239 Log file to write to.
23241 @item @code{loglevel} (default: @samp{"error"})
23242 Log level to output logs. Possible values: @samp{"silent"}, @samp{"error"},
23243 @samp{"info"} and @samp{"debug"}.
23249 @node Sound Services
23250 @subsection Sound Services
23252 @cindex sound support
23254 @cindex PulseAudio, sound support
23256 The @code{(gnu services sound)} module provides a service to configure the
23257 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
23258 preferred ALSA output driver.
23260 @deffn {Scheme Variable} alsa-service-type
23261 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
23262 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
23263 configuration file. The value for this type is a @command{alsa-configuration}
23264 record as in this example:
23267 (service alsa-service-type)
23270 See below for details about @code{alsa-configuration}.
23273 @deftp {Data Type} alsa-configuration
23274 Data type representing the configuration for @code{alsa-service}.
23277 @item @code{alsa-plugins} (default: @var{alsa-plugins})
23278 @code{alsa-plugins} package to use.
23280 @item @code{pulseaudio?} (default: @var{#t})
23281 Whether ALSA applications should transparently be made to use the
23282 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
23284 Using PulseAudio allows you to run several sound-producing applications
23285 at the same time and to individual control them @i{via}
23286 @command{pavucontrol}, among other things.
23288 @item @code{extra-options} (default: @var{""})
23289 String to append to the @file{/etc/asound.conf} file.
23294 Individual users who want to override the system configuration of ALSA can do
23295 it with the @file{~/.asoundrc} file:
23298 # In guix, we have to specify the absolute path for plugins.
23300 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
23303 # Routing ALSA to jack:
23304 # <http://jackaudio.org/faq/routing_alsa.html>.
23308 0 system:playback_1
23309 1 system:playback_2
23326 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
23329 @deffn {Scheme Variable} pulseaudio-service-type
23330 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
23331 sound server. It exists to allow system overrides of the default settings
23332 via @code{pulseaudio-configuration}, see below.
23335 This service overrides per-user configuration files. If you want
23336 PulseAudio to honor configuration files in @file{~/.config/pulse} you
23337 have to unset the environment variables @env{PULSE_CONFIG} and
23338 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
23342 This service on its own does not ensure, that the @code{pulseaudio} package
23343 exists on your machine. It merely adds configuration files for it, as
23344 detailed below. In the (admittedly unlikely) case, that you find yourself
23345 without a @code{pulseaudio} package, consider enabling it through the
23346 @code{alsa-service-type} above.
23350 @deftp {Data Type} pulseaudio-configuration
23351 Data type representing the configuration for @code{pulseaudio-service}.
23354 @item @code{client-conf} (default: @code{'()})
23355 List of settings to set in @file{client.conf}.
23356 Accepts a list of strings or symbol-value pairs. A string will be
23357 inserted as-is with a newline added. A pair will be formatted as
23358 ``key = value'', again with a newline added.
23360 @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
23361 List of settings to set in @file{daemon.conf}, formatted just like
23364 @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
23365 Script file to use as @file{default.pa}. In case the
23366 @code{extra-script-files} field below is used, an @code{.include}
23367 directive pointing to @file{/etc/pulse/default.pa.d} is appended to the
23370 @item @code{extra-script-files} (default: @code{'()})
23371 A list of file-like objects defining extra PulseAudio scripts to run at
23372 the initialization of the @command{pulseaudio} daemon, after the main
23373 @code{script-file}. The scripts are deployed to the
23374 @file{/etc/pulse/default.pa.d} directory; they should have the
23375 @samp{.pa} file name extension. For a reference of the available
23376 commands, refer to @command{man pulse-cli-syntax}.
23378 @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
23379 Script file to use as @file{system.pa}.
23382 The example below sets the default PulseAudio card profile, the default
23383 sink and the default source to use for a old SoundBlaster Audigy sound
23386 (pulseaudio-configuration
23387 (extra-script-files
23388 (list (plain-file "audigy.pa"
23390 set-card-profile alsa_card.pci-0000_01_01.0 \
23391 output:analog-surround-40+input:analog-mono
23392 set-default-source alsa_input.pci-0000_01_01.0.analog-mono
23393 set-default-sink alsa_output.pci-0000_01_01.0.analog-surround-40\n")))))
23396 Note that @code{pulseaudio-service-type} is part of
23397 @code{%desktop-services}; if your operating system declaration was
23398 derived from one of the desktop templates, you'll want to adjust the
23399 above example to modify the existing @code{pulseaudio-service-type} via
23400 @code{modify-services} (@pxref{Service Reference,
23401 @code{modify-services}}), instead of defining a new one.
23405 @deffn {Scheme Variable} ladspa-service-type
23406 This service sets the @var{LADSPA_PATH} variable, so that programs, which
23407 respect it, e.g. PulseAudio, can load LADSPA plugins.
23409 The following example will setup the service to enable modules from the
23410 @code{swh-plugins} package:
23413 (service ladspa-service-type
23414 (ladspa-configuration (plugins (list swh-plugins))))
23417 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
23422 @node Database Services
23423 @subsection Database Services
23427 The @code{(gnu services databases)} module provides the following services.
23429 @subsubheading PostgreSQL
23431 The following example describes a PostgreSQL service with the default
23435 (service postgresql-service-type
23436 (postgresql-configuration
23437 (postgresql postgresql-10)))
23440 If the services fails to start, it may be due to an incompatible
23441 cluster already present in @var{data-directory}. Adjust it (or, if you
23442 don't need the cluster anymore, delete @var{data-directory}), then
23443 restart the service.
23445 Peer authentication is used by default and the @code{postgres} user
23446 account has no shell, which prevents the direct execution of @code{psql}
23447 commands as this user. To use @code{psql}, you can temporarily log in
23448 as @code{postgres} using a shell, create a PostgreSQL superuser with the
23449 same name as one of the system users and then create the associated
23453 sudo -u postgres -s /bin/sh
23454 createuser --interactive
23455 createdb $MY_USER_LOGIN # Replace appropriately.
23458 @deftp {Data Type} postgresql-configuration
23459 Data type representing the configuration for the
23460 @code{postgresql-service-type}.
23463 @item @code{postgresql}
23464 PostgreSQL package to use for the service.
23466 @item @code{port} (default: @code{5432})
23467 Port on which PostgreSQL should listen.
23469 @item @code{locale} (default: @code{"en_US.utf8"})
23470 Locale to use as the default when creating the database cluster.
23472 @item @code{config-file} (default: @code{(postgresql-config-file)})
23473 The configuration file to use when running PostgreSQL@. The default
23474 behaviour uses the postgresql-config-file record with the default values
23477 @item @code{log-directory} (default: @code{"/var/log/postgresql"})
23478 The directory where @command{pg_ctl} output will be written in a file
23479 named @code{"pg_ctl.log"}. This file can be useful to debug PostgreSQL
23480 configuration errors for instance.
23482 @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
23483 Directory in which to store the data.
23485 @item @code{extension-packages} (default: @code{'()})
23486 @cindex postgresql extension-packages
23487 Additional extensions are loaded from packages listed in
23488 @var{extension-packages}. Extensions are available at runtime. For instance,
23489 to create a geographic database using the @code{postgis} extension, a user can
23490 configure the postgresql-service as in this example:
23494 (use-package-modules databases geo)
23498 ;; postgresql is required to run `psql' but postgis is not required for
23499 ;; proper operation.
23500 (packages (cons* postgresql %base-packages))
23503 (service postgresql-service-type
23504 (postgresql-configuration
23505 (postgresql postgresql-10)
23506 (extension-packages (list postgis))))
23510 Then the extension becomes visible and you can initialise an empty geographic
23511 database in this way:
23515 > create database postgistest;
23516 > \connect postgistest;
23517 > create extension postgis;
23518 > create extension postgis_topology;
23521 There is no need to add this field for contrib extensions such as hstore or
23522 dblink as they are already loadable by postgresql. This field is only
23523 required to add extensions provided by other packages.
23528 @deftp {Data Type} postgresql-config-file
23529 Data type representing the PostgreSQL configuration file. As shown in
23530 the following example, this can be used to customize the configuration
23531 of PostgreSQL@. Note that you can use any G-expression or filename in
23532 place of this record, if you already have a configuration file you'd
23533 like to use for example.
23536 (service postgresql-service-type
23537 (postgresql-configuration
23539 (postgresql-config-file
23540 (log-destination "stderr")
23542 (plain-file "pg_hba.conf"
23544 local all all trust
23545 host all all 127.0.0.1/32 md5
23546 host all all ::1/128 md5"))
23548 '(("session_preload_libraries" "auto_explain")
23549 ("random_page_cost" 2)
23550 ("auto_explain.log_min_duration" "100 ms")
23551 ("work_mem" "500 MB")
23552 ("logging_collector" #t)
23553 ("log_directory" "/var/log/postgresql")))))))
23557 @item @code{log-destination} (default: @code{"syslog"})
23558 The logging method to use for PostgreSQL@. Multiple values are accepted,
23559 separated by commas.
23561 @item @code{hba-file} (default: @code{%default-postgres-hba})
23562 Filename or G-expression for the host-based authentication
23565 @item @code{ident-file} (default: @code{%default-postgres-ident})
23566 Filename or G-expression for the user name mapping configuration.
23568 @item @code{socket-directory} (default: @code{"/var/run/postgresql"})
23569 Specifies the directory of the Unix-domain socket(s) on which PostgreSQL
23570 is to listen for connections from client applications. If set to
23571 @code{""} PostgreSQL does not listen on any Unix-domain sockets, in
23572 which case only TCP/IP sockets can be used to connect to the server.
23574 By default, the @code{#false} value means the PostgreSQL default value
23575 will be used, which is currently @samp{/tmp}.
23577 @item @code{extra-config} (default: @code{'()})
23578 List of additional keys and values to include in the PostgreSQL config
23579 file. Each entry in the list should be a list where the first element
23580 is the key, and the remaining elements are the values.
23582 The values can be numbers, booleans or strings and will be mapped to
23583 PostgreSQL parameters types @code{Boolean}, @code{String},
23584 @code{Numeric}, @code{Numeric with Unit} and @code{Enumerated} described
23585 @uref{https://www.postgresql.org/docs/current/config-setting.html,
23591 @deffn {Scheme Variable} postgresql-role-service-type
23592 This service allows to create PostgreSQL roles and databases after
23593 PostgreSQL service start. Here is an example of its use.
23596 (service postgresql-role-service-type
23597 (postgresql-role-configuration
23599 (list (postgresql-role
23601 (create-database? #t))))))
23604 This service can be extended with extra roles, as in this
23608 (service-extension postgresql-role-service-type
23609 (const (postgresql-role
23611 (create-database? #t))))
23615 @deftp {Data Type} postgresql-role
23616 PostgreSQL manages database access permissions using the concept of
23617 roles. A role can be thought of as either a database user, or a group
23618 of database users, depending on how the role is set up. Roles can own
23619 database objects (for example, tables) and can assign privileges on
23620 those objects to other roles to control who has access to which objects.
23626 @item @code{permissions} (default: @code{'(createdb login)})
23627 The role permissions list. Supported permissions are @code{bypassrls},
23628 @code{createdb}, @code{createrole}, @code{login}, @code{replication} and
23631 @item @code{create-database?} (default: @code{#f})
23632 Whether to create a database with the same name as the role.
23637 @deftp {Data Type} postgresql-role-configuration
23638 Data type representing the configuration of
23639 @var{postgresql-role-service-type}.
23642 @item @code{host} (default: @code{"/var/run/postgresql"})
23643 The PostgreSQL host to connect to.
23645 @item @code{log} (default: @code{"/var/log/postgresql_roles.log"})
23646 File name of the log file.
23648 @item @code{roles} (default: @code{'()})
23649 The initial PostgreSQL roles to create.
23653 @subsubheading MariaDB/MySQL
23655 @defvr {Scheme Variable} mysql-service-type
23656 This is the service type for a MySQL or MariaDB database server. Its value
23657 is a @code{mysql-configuration} object that specifies which package to use,
23658 as well as various settings for the @command{mysqld} daemon.
23661 @deftp {Data Type} mysql-configuration
23662 Data type representing the configuration of @var{mysql-service-type}.
23665 @item @code{mysql} (default: @var{mariadb})
23666 Package object of the MySQL database server, can be either @var{mariadb}
23669 For MySQL, a temporary root password will be displayed at activation time.
23670 For MariaDB, the root password is empty.
23672 @item @code{bind-address} (default: @code{"127.0.0.1"})
23673 The IP on which to listen for network connections. Use @code{"0.0.0.0"}
23674 to bind to all available network interfaces.
23676 @item @code{port} (default: @code{3306})
23677 TCP port on which the database server listens for incoming connections.
23679 @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
23680 Socket file to use for local (non-network) connections.
23682 @item @code{extra-content} (default: @code{""})
23683 Additional settings for the @file{my.cnf} configuration file.
23685 @item @code{extra-environment} (default: @code{#~'()})
23686 List of environment variables passed to the @command{mysqld} process.
23688 @item @code{auto-upgrade?} (default: @code{#t})
23689 Whether to automatically run @command{mysql_upgrade} after starting the
23690 service. This is necessary to upgrade the @dfn{system schema} after
23691 ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
23692 be disabled if you would rather do that manually.
23697 @subsubheading Memcached
23699 @defvr {Scheme Variable} memcached-service-type
23700 This is the service type for the @uref{https://memcached.org/,
23701 Memcached} service, which provides a distributed in memory cache. The
23702 value for the service type is a @code{memcached-configuration} object.
23706 (service memcached-service-type)
23709 @deftp {Data Type} memcached-configuration
23710 Data type representing the configuration of memcached.
23713 @item @code{memcached} (default: @code{memcached})
23714 The Memcached package to use.
23716 @item @code{interfaces} (default: @code{'("0.0.0.0")})
23717 Network interfaces on which to listen.
23719 @item @code{tcp-port} (default: @code{11211})
23720 Port on which to accept connections.
23722 @item @code{udp-port} (default: @code{11211})
23723 Port on which to accept UDP connections on, a value of 0 will disable
23724 listening on a UDP socket.
23726 @item @code{additional-options} (default: @code{'()})
23727 Additional command line options to pass to @code{memcached}.
23731 @subsubheading Redis
23733 @defvr {Scheme Variable} redis-service-type
23734 This is the service type for the @uref{https://redis.io/, Redis}
23735 key/value store, whose value is a @code{redis-configuration} object.
23738 @deftp {Data Type} redis-configuration
23739 Data type representing the configuration of redis.
23742 @item @code{redis} (default: @code{redis})
23743 The Redis package to use.
23745 @item @code{bind} (default: @code{"127.0.0.1"})
23746 Network interface on which to listen.
23748 @item @code{port} (default: @code{6379})
23749 Port on which to accept connections on, a value of 0 will disable
23750 listening on a TCP socket.
23752 @item @code{working-directory} (default: @code{"/var/lib/redis"})
23753 Directory in which to store the database and related files.
23757 @node Mail Services
23758 @subsection Mail Services
23762 The @code{(gnu services mail)} module provides Guix service definitions
23763 for email services: IMAP, POP3, and LMTP servers, as well as mail
23764 transport agents (MTAs). Lots of acronyms! These services are detailed
23765 in the subsections below.
23767 @subsubheading Dovecot Service
23769 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
23770 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
23773 By default, Dovecot does not need much configuration; the default
23774 configuration object created by @code{(dovecot-configuration)} will
23775 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
23776 certificate will be generated for TLS-protected connections, though
23777 Dovecot will also listen on cleartext ports by default. There are a
23778 number of options, though, which mail administrators might need to change,
23779 and as is the case with other services, Guix allows the system
23780 administrator to specify these parameters via a uniform Scheme interface.
23782 For example, to specify that mail is located at @code{maildir~/.mail},
23783 one would instantiate the Dovecot service like this:
23786 (dovecot-service #:config
23787 (dovecot-configuration
23788 (mail-location "maildir:~/.mail")))
23791 The available configuration parameters follow. Each parameter
23792 definition is preceded by its type; for example, @samp{string-list foo}
23793 indicates that the @code{foo} parameter should be specified as a list of
23794 strings. There is also a way to specify the configuration as a string,
23795 if you have an old @code{dovecot.conf} file that you want to port over
23796 from some other system; see the end for more details.
23798 @c The following documentation was initially generated by
23799 @c (generate-documentation) in (gnu services mail). Manually maintained
23800 @c documentation is better, so we shouldn't hesitate to edit below as
23801 @c needed. However if the change you want to make to this documentation
23802 @c can be done in an automated way, it's probably easier to change
23803 @c (generate-documentation) than to make it below and have to deal with
23804 @c the churn as dovecot updates.
23806 Available @code{dovecot-configuration} fields are:
23808 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
23809 The dovecot package.
23812 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
23813 A list of IPs or hosts where to listen for connections. @samp{*}
23814 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
23815 interfaces. If you want to specify non-default ports or anything more
23816 complex, customize the address and port fields of the
23817 @samp{inet-listener} of the specific services you are interested in.
23820 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
23821 List of protocols we want to serve. Available protocols include
23822 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
23824 Available @code{protocol-configuration} fields are:
23826 @deftypevr {@code{protocol-configuration} parameter} string name
23827 The name of the protocol.
23830 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
23831 UNIX socket path to the master authentication server to find users.
23832 This is used by imap (for shared users) and lda.
23833 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
23836 @deftypevr {@code{protocol-configuration} parameter} boolean imap-metadata?
23837 Whether to enable the @code{IMAP METADATA} extension as defined in
23838 @uref{https://tools.ietf.org/html/rfc5464,RFC@tie{}5464}, which provides
23839 a means for clients to set and retrieve per-mailbox, per-user metadata
23840 and annotations over IMAP.
23842 If this is @samp{#t}, you must also specify a dictionary @i{via} the
23843 @code{mail-attribute-dict} setting.
23845 Defaults to @samp{#f}.
23849 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-notify-capabilities
23850 Which NOTIFY capabilities to report to clients that first connect to
23851 the ManageSieve service, before authentication. These may differ from the
23852 capabilities offered to authenticated users. If this field is left empty,
23853 report what the Sieve interpreter supports by default.
23855 Defaults to @samp{()}.
23858 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-sieve-capability
23859 Which SIEVE capabilities to report to clients that first connect to
23860 the ManageSieve service, before authentication. These may differ from the
23861 capabilities offered to authenticated users. If this field is left empty,
23862 report what the Sieve interpreter supports by default.
23864 Defaults to @samp{()}.
23868 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
23869 Space separated list of plugins to load.
23872 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
23873 Maximum number of IMAP connections allowed for a user from each IP
23874 address. NOTE: The username is compared case-sensitively.
23875 Defaults to @samp{10}.
23880 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
23881 List of services to enable. Available services include @samp{imap},
23882 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
23885 Available @code{service-configuration} fields are:
23887 @deftypevr {@code{service-configuration} parameter} string kind
23888 The service kind. Valid values include @code{director},
23889 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
23890 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
23891 @code{tcpwrap}, @code{quota-warning}, or anything else.
23894 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
23895 Listeners for the service. A listener is either a
23896 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
23897 an @code{inet-listener-configuration}.
23898 Defaults to @samp{()}.
23900 Available @code{unix-listener-configuration} fields are:
23902 @deftypevr {@code{unix-listener-configuration} parameter} string path
23903 Path to the file, relative to @code{base-dir} field. This is also used as
23907 @deftypevr {@code{unix-listener-configuration} parameter} string mode
23908 The access mode for the socket.
23909 Defaults to @samp{"0600"}.
23912 @deftypevr {@code{unix-listener-configuration} parameter} string user
23913 The user to own the socket.
23914 Defaults to @samp{""}.
23917 @deftypevr {@code{unix-listener-configuration} parameter} string group
23918 The group to own the socket.
23919 Defaults to @samp{""}.
23923 Available @code{fifo-listener-configuration} fields are:
23925 @deftypevr {@code{fifo-listener-configuration} parameter} string path
23926 Path to the file, relative to @code{base-dir} field. This is also used as
23930 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
23931 The access mode for the socket.
23932 Defaults to @samp{"0600"}.
23935 @deftypevr {@code{fifo-listener-configuration} parameter} string user
23936 The user to own the socket.
23937 Defaults to @samp{""}.
23940 @deftypevr {@code{fifo-listener-configuration} parameter} string group
23941 The group to own the socket.
23942 Defaults to @samp{""}.
23946 Available @code{inet-listener-configuration} fields are:
23948 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
23949 The protocol to listen for.
23952 @deftypevr {@code{inet-listener-configuration} parameter} string address
23953 The address on which to listen, or empty for all addresses.
23954 Defaults to @samp{""}.
23957 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
23958 The port on which to listen.
23961 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
23962 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
23964 Defaults to @samp{#t}.
23969 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
23970 Maximum number of simultaneous client connections per process. Once
23971 this number of connections is received, the next incoming connection
23972 will prompt Dovecot to spawn another process. If set to 0,
23973 @code{default-client-limit} is used instead.
23975 Defaults to @samp{0}.
23979 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
23980 Number of connections to handle before starting a new process.
23981 Typically the only useful values are 0 (unlimited) or 1. 1 is more
23982 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
23983 Defaults to @samp{1}.
23987 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
23988 Maximum number of processes that can exist for this service. If set to
23989 0, @code{default-process-limit} is used instead.
23991 Defaults to @samp{0}.
23995 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
23996 Number of processes to always keep waiting for more connections.
23997 Defaults to @samp{0}.
24000 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
24001 If you set @samp{service-count 0}, you probably need to grow
24003 Defaults to @samp{256000000}.
24008 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
24009 Dict configuration, as created by the @code{dict-configuration}
24012 Available @code{dict-configuration} fields are:
24014 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
24015 A list of key-value pairs that this dict should hold.
24016 Defaults to @samp{()}.
24021 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
24022 A list of passdb configurations, each one created by the
24023 @code{passdb-configuration} constructor.
24025 Available @code{passdb-configuration} fields are:
24027 @deftypevr {@code{passdb-configuration} parameter} string driver
24028 The driver that the passdb should use. Valid values include
24029 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
24031 Defaults to @samp{"pam"}.
24034 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
24035 Space separated list of arguments to the passdb driver.
24036 Defaults to @samp{""}.
24041 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
24042 List of userdb configurations, each one created by the
24043 @code{userdb-configuration} constructor.
24045 Available @code{userdb-configuration} fields are:
24047 @deftypevr {@code{userdb-configuration} parameter} string driver
24048 The driver that the userdb should use. Valid values include
24049 @samp{passwd} and @samp{static}.
24050 Defaults to @samp{"passwd"}.
24053 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
24054 Space separated list of arguments to the userdb driver.
24055 Defaults to @samp{""}.
24058 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
24059 Override fields from passwd.
24060 Defaults to @samp{()}.
24065 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
24066 Plug-in configuration, created by the @code{plugin-configuration}
24070 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
24071 List of namespaces. Each item in the list is created by the
24072 @code{namespace-configuration} constructor.
24074 Available @code{namespace-configuration} fields are:
24076 @deftypevr {@code{namespace-configuration} parameter} string name
24077 Name for this namespace.
24080 @deftypevr {@code{namespace-configuration} parameter} string type
24081 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
24082 Defaults to @samp{"private"}.
24085 @deftypevr {@code{namespace-configuration} parameter} string separator
24086 Hierarchy separator to use. You should use the same separator for
24087 all namespaces or some clients get confused. @samp{/} is usually a good
24088 one. The default however depends on the underlying mail storage
24090 Defaults to @samp{""}.
24093 @deftypevr {@code{namespace-configuration} parameter} string prefix
24094 Prefix required to access this namespace. This needs to be
24095 different for all namespaces. For example @samp{Public/}.
24096 Defaults to @samp{""}.
24099 @deftypevr {@code{namespace-configuration} parameter} string location
24100 Physical location of the mailbox. This is in the same format as
24101 mail_location, which is also the default for it.
24102 Defaults to @samp{""}.
24105 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
24106 There can be only one INBOX, and this setting defines which
24108 Defaults to @samp{#f}.
24111 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
24112 If namespace is hidden, it's not advertised to clients via NAMESPACE
24113 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
24114 useful when converting from another server with different namespaces
24115 which you want to deprecate but still keep working. For example you can
24116 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
24118 Defaults to @samp{#f}.
24121 @deftypevr {@code{namespace-configuration} parameter} boolean list?
24122 Show the mailboxes under this namespace with the LIST command. This
24123 makes the namespace visible for clients that do not support the NAMESPACE
24124 extension. The special @code{children} value lists child mailboxes, but
24125 hides the namespace prefix.
24126 Defaults to @samp{#t}.
24129 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
24130 Namespace handles its own subscriptions. If set to @code{#f}, the
24131 parent namespace handles them. The empty prefix should always have this
24133 Defaults to @samp{#t}.
24136 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
24137 List of predefined mailboxes in this namespace.
24138 Defaults to @samp{()}.
24140 Available @code{mailbox-configuration} fields are:
24142 @deftypevr {@code{mailbox-configuration} parameter} string name
24143 Name for this mailbox.
24146 @deftypevr {@code{mailbox-configuration} parameter} string auto
24147 @samp{create} will automatically create this mailbox.
24148 @samp{subscribe} will both create and subscribe to the mailbox.
24149 Defaults to @samp{"no"}.
24152 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
24153 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
24154 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
24155 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
24156 Defaults to @samp{()}.
24163 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
24164 Base directory where to store runtime data.
24165 Defaults to @samp{"/var/run/dovecot/"}.
24168 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
24169 Greeting message for clients.
24170 Defaults to @samp{"Dovecot ready."}.
24173 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
24174 List of trusted network ranges. Connections from these IPs are
24175 allowed to override their IP addresses and ports (for logging and for
24176 authentication checks). @samp{disable-plaintext-auth} is also ignored
24177 for these networks. Typically you would specify your IMAP proxy servers
24179 Defaults to @samp{()}.
24182 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
24183 List of login access check sockets (e.g.@: tcpwrap).
24184 Defaults to @samp{()}.
24187 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
24188 Show more verbose process titles (in ps). Currently shows user name
24189 and IP address. Useful for seeing who is actually using the IMAP
24190 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
24192 Defaults to @samp{#f}.
24195 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
24196 Should all processes be killed when Dovecot master process shuts down.
24197 Setting this to @code{#f} means that Dovecot can be upgraded without
24198 forcing existing client connections to close (although that could also
24199 be a problem if the upgrade is e.g.@: due to a security fix).
24200 Defaults to @samp{#t}.
24203 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
24204 If non-zero, run mail commands via this many connections to doveadm
24205 server, instead of running them directly in the same process.
24206 Defaults to @samp{0}.
24209 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
24210 UNIX socket or host:port used for connecting to doveadm server.
24211 Defaults to @samp{"doveadm-server"}.
24214 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
24215 List of environment variables that are preserved on Dovecot startup
24216 and passed down to all of its child processes. You can also give
24217 key=value pairs to always set specific settings.
24220 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
24221 Disable LOGIN command and all other plaintext authentications unless
24222 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
24223 matches the local IP (i.e.@: you're connecting from the same computer),
24224 the connection is considered secure and plaintext authentication is
24225 allowed. See also ssl=required setting.
24226 Defaults to @samp{#t}.
24229 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
24230 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
24231 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
24232 for caching to be used.
24233 Defaults to @samp{0}.
24236 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
24237 Time to live for cached data. After TTL expires the cached record
24238 is no longer used, *except* if the main database lookup returns internal
24239 failure. We also try to handle password changes automatically: If
24240 user's previous authentication was successful, but this one wasn't, the
24241 cache isn't used. For now this works only with plaintext
24243 Defaults to @samp{"1 hour"}.
24246 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
24247 TTL for negative hits (user not found, password mismatch).
24248 0 disables caching them completely.
24249 Defaults to @samp{"1 hour"}.
24252 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
24253 List of realms for SASL authentication mechanisms that need them.
24254 You can leave it empty if you don't want to support multiple realms.
24255 Many clients simply use the first one listed here, so keep the default
24257 Defaults to @samp{()}.
24260 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
24261 Default realm/domain to use if none was specified. This is used for
24262 both SASL realms and appending @@domain to username in plaintext
24264 Defaults to @samp{""}.
24267 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
24268 List of allowed characters in username. If the user-given username
24269 contains a character not listed in here, the login automatically fails.
24270 This is just an extra check to make sure user can't exploit any
24271 potential quote escaping vulnerabilities with SQL/LDAP databases. If
24272 you want to allow all characters, set this value to empty.
24273 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
24276 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
24277 Username character translations before it's looked up from
24278 databases. The value contains series of from -> to characters. For
24279 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
24280 translated to @samp{@@}.
24281 Defaults to @samp{""}.
24284 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
24285 Username formatting before it's looked up from databases. You can
24286 use the standard variables here, e.g.@: %Lu would lowercase the username,
24287 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
24288 change the @samp{@@} into @samp{-AT-}. This translation is done after
24289 @samp{auth-username-translation} changes.
24290 Defaults to @samp{"%Lu"}.
24293 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
24294 If you want to allow master users to log in by specifying the master
24295 username within the normal username string (i.e.@: not using SASL
24296 mechanism's support for it), you can specify the separator character
24297 here. The format is then <username><separator><master username>.
24298 UW-IMAP uses @samp{*} as the separator, so that could be a good
24300 Defaults to @samp{""}.
24303 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
24304 Username to use for users logging in with ANONYMOUS SASL
24306 Defaults to @samp{"anonymous"}.
24309 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
24310 Maximum number of dovecot-auth worker processes. They're used to
24311 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
24312 They're automatically created and destroyed as needed.
24313 Defaults to @samp{30}.
24316 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
24317 Host name to use in GSSAPI principal names. The default is to use
24318 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
24319 allow all keytab entries.
24320 Defaults to @samp{""}.
24323 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
24324 Kerberos keytab to use for the GSSAPI mechanism. Will use the
24325 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
24326 need to change the auth service to run as root to be able to read this
24328 Defaults to @samp{""}.
24331 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
24332 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
24333 and @samp{ntlm-auth} helper.
24334 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
24335 Defaults to @samp{#f}.
24338 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
24339 Path for Samba's @samp{ntlm-auth} helper binary.
24340 Defaults to @samp{"/usr/bin/ntlm_auth"}.
24343 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
24344 Time to delay before replying to failed authentications.
24345 Defaults to @samp{"2 secs"}.
24348 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
24349 Require a valid SSL client certificate or the authentication
24351 Defaults to @samp{#f}.
24354 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
24355 Take the username from client's SSL certificate, using
24356 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
24358 Defaults to @samp{#f}.
24361 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
24362 List of wanted authentication mechanisms. Supported mechanisms are:
24363 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
24364 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
24365 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
24366 @samp{disable-plaintext-auth} setting.
24369 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
24370 List of IPs or hostnames to all director servers, including ourself.
24371 Ports can be specified as ip:port. The default port is the same as what
24372 director service's @samp{inet-listener} is using.
24373 Defaults to @samp{()}.
24376 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
24377 List of IPs or hostnames to all backend mail servers. Ranges are
24378 allowed too, like 10.0.0.10-10.0.0.30.
24379 Defaults to @samp{()}.
24382 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
24383 How long to redirect users to a specific server after it no longer
24384 has any connections.
24385 Defaults to @samp{"15 min"}.
24388 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
24389 How the username is translated before being hashed. Useful values
24390 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
24391 are shared within domain.
24392 Defaults to @samp{"%Lu"}.
24395 @deftypevr {@code{dovecot-configuration} parameter} string log-path
24396 Log file to use for error messages. @samp{syslog} logs to syslog,
24397 @samp{/dev/stderr} logs to stderr.
24398 Defaults to @samp{"syslog"}.
24401 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
24402 Log file to use for informational messages. Defaults to
24404 Defaults to @samp{""}.
24407 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
24408 Log file to use for debug messages. Defaults to
24409 @samp{info-log-path}.
24410 Defaults to @samp{""}.
24413 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
24414 Syslog facility to use if you're logging to syslog. Usually if you
24415 don't want to use @samp{mail}, you'll use local0..local7. Also other
24416 standard facilities are supported.
24417 Defaults to @samp{"mail"}.
24420 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
24421 Log unsuccessful authentication attempts and the reasons why they
24423 Defaults to @samp{#f}.
24426 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
24427 In case of password mismatches, log the attempted password. Valid
24428 values are no, plain and sha1. sha1 can be useful for detecting brute
24429 force password attempts vs. user simply trying the same password over
24430 and over again. You can also truncate the value to n chars by appending
24431 ":n" (e.g.@: sha1:6).
24432 Defaults to @samp{"no"}.
24435 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
24436 Even more verbose logging for debugging purposes. Shows for example
24438 Defaults to @samp{#f}.
24441 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
24442 In case of password mismatches, log the passwords and used scheme so
24443 the problem can be debugged. Enabling this also enables
24445 Defaults to @samp{#f}.
24448 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
24449 Enable mail process debugging. This can help you figure out why
24450 Dovecot isn't finding your mails.
24451 Defaults to @samp{#f}.
24454 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
24455 Show protocol level SSL errors.
24456 Defaults to @samp{#f}.
24459 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
24460 Prefix for each line written to log file. % codes are in
24461 strftime(3) format.
24462 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
24465 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
24466 List of elements we want to log. The elements which have a
24467 non-empty variable value are joined together to form a comma-separated
24471 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
24472 Login log format. %s contains @samp{login-log-format-elements}
24473 string, %$ contains the data we want to log.
24474 Defaults to @samp{"%$: %s"}.
24477 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
24478 Log prefix for mail processes. See doc/wiki/Variables.txt for list
24479 of possible variables you can use.
24480 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
24483 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
24484 Format to use for logging mail deliveries. You can use variables:
24487 Delivery status message (e.g.@: @samp{saved to INBOX})
24499 Defaults to @samp{"msgid=%m: %$"}.
24502 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
24503 Location for users' mailboxes. The default is empty, which means
24504 that Dovecot tries to find the mailboxes automatically. This won't work
24505 if the user doesn't yet have any mail, so you should explicitly tell
24506 Dovecot the full location.
24508 If you're using mbox, giving a path to the INBOX
24509 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
24510 where the other mailboxes are kept. This is called the @emph{root mail
24511 directory}, and it must be the first path given in the
24512 @samp{mail-location} setting.
24514 There are a few special variables you can use, e.g.:
24520 user part in user@@domain, same as %u if there's no domain
24522 domain part in user@@domain, empty if there's no domain
24527 See doc/wiki/Variables.txt for full list. Some examples:
24529 @item maildir:~/Maildir
24530 @item mbox:~/mail:INBOX=/var/mail/%u
24531 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
24533 Defaults to @samp{""}.
24536 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
24537 System user and group used to access mails. If you use multiple,
24538 userdb can override these by returning uid or gid fields. You can use
24539 either numbers or names. <doc/wiki/UserIds.txt>.
24540 Defaults to @samp{""}.
24543 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
24545 Defaults to @samp{""}.
24548 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
24549 Group to enable temporarily for privileged operations. Currently
24550 this is used only with INBOX when either its initial creation or
24551 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
24553 Defaults to @samp{""}.
24556 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
24557 Grant access to these supplementary groups for mail processes.
24558 Typically these are used to set up access to shared mailboxes. Note
24559 that it may be dangerous to set these if users can create symlinks
24560 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
24561 could allow a user to delete others' mailboxes, or @code{ln -s
24562 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
24566 @deftypevr {@code{dovecot-configuration} parameter} string mail-attribute-dict
24567 The location of a dictionary used to store @code{IMAP METADATA}
24568 as defined by @uref{https://tools.ietf.org/html/rfc5464, RFC@tie{}5464}.
24570 The IMAP METADATA commands are available only if the ``imap''
24571 protocol configuration's @code{imap-metadata?} field is @samp{#t}.
24573 Defaults to @samp{""}.
24577 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
24578 Allow full file system access to clients. There's no access checks
24579 other than what the operating system does for the active UID/GID@. It
24580 works with both maildir and mboxes, allowing you to prefix mailboxes
24581 names with e.g.@: @file{/path/} or @file{~user/}.
24582 Defaults to @samp{#f}.
24585 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
24586 Don't use @code{mmap()} at all. This is required if you store indexes to
24587 shared file systems (NFS or clustered file system).
24588 Defaults to @samp{#f}.
24591 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
24592 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
24593 supports @samp{O_EXCL} since version 3, so this should be safe to use
24594 nowadays by default.
24595 Defaults to @samp{#t}.
24598 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
24599 When to use fsync() or fdatasync() calls:
24602 Whenever necessary to avoid losing important data
24604 Useful with e.g.@: NFS when @code{write()}s are delayed
24606 Never use it (best performance, but crashes can lose data).
24608 Defaults to @samp{"optimized"}.
24611 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
24612 Mail storage exists in NFS@. Set this to yes to make Dovecot flush
24613 NFS caches whenever needed. If you're using only a single mail server
24615 Defaults to @samp{#f}.
24618 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
24619 Mail index files also exist in NFS@. Setting this to yes requires
24620 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
24621 Defaults to @samp{#f}.
24624 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
24625 Locking method for index files. Alternatives are fcntl, flock and
24626 dotlock. Dotlocking uses some tricks which may create more disk I/O
24627 than other locking methods. NFS users: flock doesn't work, remember to
24628 change @samp{mmap-disable}.
24629 Defaults to @samp{"fcntl"}.
24632 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
24633 Directory in which LDA/LMTP temporarily stores incoming mails >128
24635 Defaults to @samp{"/tmp"}.
24638 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
24639 Valid UID range for users. This is mostly to make sure that users can't
24640 log in as daemons or other system users. Note that denying root logins is
24641 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
24643 Defaults to @samp{500}.
24646 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
24648 Defaults to @samp{0}.
24651 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
24652 Valid GID range for users. Users having non-valid GID as primary group ID
24653 aren't allowed to log in. If user belongs to supplementary groups with
24654 non-valid GIDs, those groups are not set.
24655 Defaults to @samp{1}.
24658 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
24660 Defaults to @samp{0}.
24663 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
24664 Maximum allowed length for mail keyword name. It's only forced when
24665 trying to create new keywords.
24666 Defaults to @samp{50}.
24669 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
24670 List of directories under which chrooting is allowed for mail
24671 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
24672 too). This setting doesn't affect @samp{login-chroot}
24673 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
24674 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
24675 which local users can modify, that may lead to root exploit. Usually
24676 this should be done only if you don't allow shell access for users.
24677 <doc/wiki/Chrooting.txt>.
24678 Defaults to @samp{()}.
24681 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
24682 Default chroot directory for mail processes. This can be overridden
24683 for specific users in user database by giving @samp{/./} in user's home
24684 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
24685 there is no real need to do chrooting, Dovecot doesn't allow users to
24686 access files outside their mail directory anyway. If your home
24687 directories are prefixed with the chroot directory, append @samp{/.} to
24688 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
24689 Defaults to @samp{""}.
24692 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
24693 UNIX socket path to master authentication server to find users.
24694 This is used by imap (for shared users) and lda.
24695 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
24698 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
24699 Directory where to look up mail plugins.
24700 Defaults to @samp{"/usr/lib/dovecot"}.
24703 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
24704 List of plugins to load for all services. Plugins specific to IMAP,
24705 LDA, etc.@: are added to this list in their own .conf files.
24706 Defaults to @samp{()}.
24709 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
24710 The minimum number of mails in a mailbox before updates are done to
24711 cache file. This allows optimizing Dovecot's behavior to do less disk
24712 writes at the cost of more disk reads.
24713 Defaults to @samp{0}.
24716 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
24717 When IDLE command is running, mailbox is checked once in a while to
24718 see if there are any new mails or other changes. This setting defines
24719 the minimum time to wait between those checks. Dovecot can also use
24720 dnotify, inotify and kqueue to find out immediately when changes
24722 Defaults to @samp{"30 secs"}.
24725 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
24726 Save mails with CR+LF instead of plain LF@. This makes sending those
24727 mails take less CPU, especially with sendfile() syscall with Linux and
24728 FreeBSD@. But it also creates a bit more disk I/O which may just make it
24729 slower. Also note that if other software reads the mboxes/maildirs,
24730 they may handle the extra CRs wrong and cause problems.
24731 Defaults to @samp{#f}.
24734 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
24735 By default LIST command returns all entries in maildir beginning
24736 with a dot. Enabling this option makes Dovecot return only entries
24737 which are directories. This is done by stat()ing each entry, so it
24738 causes more disk I/O.
24739 (For systems setting struct @samp{dirent->d_type} this check is free
24740 and it's done always regardless of this setting).
24741 Defaults to @samp{#f}.
24744 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
24745 When copying a message, do it with hard links whenever possible.
24746 This makes the performance much better, and it's unlikely to have any
24748 Defaults to @samp{#t}.
24751 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
24752 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
24753 directory only when its mtime changes unexpectedly or when we can't find
24754 the mail otherwise.
24755 Defaults to @samp{#f}.
24758 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
24759 Which locking methods to use for locking mbox. There are four
24764 Create <mailbox>.lock file. This is the oldest and most NFS-safe
24765 solution. If you want to use /var/mail/ like directory, the users will
24766 need write access to that directory.
24768 Same as dotlock, but if it fails because of permissions or because there
24769 isn't enough disk space, just skip it.
24771 Use this if possible. Works with NFS too if lockd is used.
24773 May not exist in all systems. Doesn't work with NFS.
24775 May not exist in all systems. Doesn't work with NFS.
24778 You can use multiple locking methods; if you do the order they're declared
24779 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
24780 locking methods as well. Some operating systems don't allow using some of
24781 them simultaneously.
24784 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
24788 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
24789 Maximum time to wait for lock (all of them) before aborting.
24790 Defaults to @samp{"5 mins"}.
24793 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
24794 If dotlock exists but the mailbox isn't modified in any way,
24795 override the lock file after this much time.
24796 Defaults to @samp{"2 mins"}.
24799 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
24800 When mbox changes unexpectedly we have to fully read it to find out
24801 what changed. If the mbox is large this can take a long time. Since
24802 the change is usually just a newly appended mail, it'd be faster to
24803 simply read the new mails. If this setting is enabled, Dovecot does
24804 this but still safely fallbacks to re-reading the whole mbox file
24805 whenever something in mbox isn't how it's expected to be. The only real
24806 downside to this setting is that if some other MUA changes message
24807 flags, Dovecot doesn't notice it immediately. Note that a full sync is
24808 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
24809 Defaults to @samp{#t}.
24812 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
24813 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
24814 EXAMINE, EXPUNGE or CHECK commands. If this is set,
24815 @samp{mbox-dirty-syncs} is ignored.
24816 Defaults to @samp{#f}.
24819 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
24820 Delay writing mbox headers until doing a full write sync (EXPUNGE
24821 and CHECK commands and when closing the mailbox). This is especially
24822 useful for POP3 where clients often delete all mails. The downside is
24823 that our changes aren't immediately visible to other MUAs.
24824 Defaults to @samp{#t}.
24827 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
24828 If mbox size is smaller than this (e.g.@: 100k), don't write index
24829 files. If an index file already exists it's still read, just not
24831 Defaults to @samp{0}.
24834 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
24835 Maximum dbox file size until it's rotated.
24836 Defaults to @samp{10000000}.
24839 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
24840 Maximum dbox file age until it's rotated. Typically in days. Day
24841 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
24843 Defaults to @samp{"1d"}.
24846 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
24847 When creating new mdbox files, immediately preallocate their size to
24848 @samp{mdbox-rotate-size}. This setting currently works only in Linux
24849 with some file systems (ext4, xfs).
24850 Defaults to @samp{#f}.
24853 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
24854 sdbox and mdbox support saving mail attachments to external files,
24855 which also allows single instance storage for them. Other backends
24856 don't support this for now.
24858 WARNING: This feature hasn't been tested much yet. Use at your own risk.
24860 Directory root where to store mail attachments. Disabled, if empty.
24861 Defaults to @samp{""}.
24864 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
24865 Attachments smaller than this aren't saved externally. It's also
24866 possible to write a plugin to disable saving specific attachments
24868 Defaults to @samp{128000}.
24871 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
24872 File system backend to use for saving attachments:
24875 No SiS done by Dovecot (but this might help FS's own deduplication)
24877 SiS with immediate byte-by-byte comparison during saving
24878 @item sis-queue posix
24879 SiS with delayed comparison and deduplication.
24881 Defaults to @samp{"sis posix"}.
24884 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
24885 Hash format to use in attachment filenames. You can add any text and
24886 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
24887 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
24888 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
24889 Defaults to @samp{"%@{sha1@}"}.
24892 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
24894 Defaults to @samp{100}.
24897 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
24899 Defaults to @samp{1000}.
24902 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
24903 Default VSZ (virtual memory size) limit for service processes.
24904 This is mainly intended to catch and kill processes that leak memory
24905 before they eat up everything.
24906 Defaults to @samp{256000000}.
24909 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
24910 Login user is internally used by login processes. This is the most
24911 untrusted user in Dovecot system. It shouldn't have access to anything
24913 Defaults to @samp{"dovenull"}.
24916 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
24917 Internal user is used by unprivileged processes. It should be
24918 separate from login user, so that login processes can't disturb other
24920 Defaults to @samp{"dovecot"}.
24923 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
24924 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
24925 Defaults to @samp{"required"}.
24928 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
24929 PEM encoded X.509 SSL/TLS certificate (public key).
24930 Defaults to @samp{"</etc/dovecot/default.pem"}.
24933 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
24934 PEM encoded SSL/TLS private key. The key is opened before
24935 dropping root privileges, so keep the key file unreadable by anyone but
24937 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
24940 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
24941 If key file is password protected, give the password here.
24942 Alternatively give it when starting dovecot with -p parameter. Since
24943 this file is often world-readable, you may want to place this setting
24944 instead to a different.
24945 Defaults to @samp{""}.
24948 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
24949 PEM encoded trusted certificate authority. Set this only if you
24950 intend to use @samp{ssl-verify-client-cert? #t}. The file should
24951 contain the CA certificate(s) followed by the matching
24952 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
24953 Defaults to @samp{""}.
24956 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
24957 Require that CRL check succeeds for client certificates.
24958 Defaults to @samp{#t}.
24961 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
24962 Request client to send a certificate. If you also want to require
24963 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
24964 Defaults to @samp{#f}.
24967 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
24968 Which field from certificate to use for username. commonName and
24969 x500UniqueIdentifier are the usual choices. You'll also need to set
24970 @samp{auth-ssl-username-from-cert? #t}.
24971 Defaults to @samp{"commonName"}.
24974 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
24975 Minimum SSL protocol version to accept.
24976 Defaults to @samp{"TLSv1"}.
24979 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
24980 SSL ciphers to use.
24981 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
24984 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
24985 SSL crypto device to use, for valid values run "openssl engine".
24986 Defaults to @samp{""}.
24989 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
24990 Address to use when sending rejection mails.
24991 %d expands to recipient domain.
24992 Defaults to @samp{"postmaster@@%d"}.
24995 @deftypevr {@code{dovecot-configuration} parameter} string hostname
24996 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
24997 and in LMTP replies. Default is the system's real hostname@@domain.
24998 Defaults to @samp{""}.
25001 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
25002 If user is over quota, return with temporary failure instead of
25004 Defaults to @samp{#f}.
25007 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
25008 Binary to use for sending mails.
25009 Defaults to @samp{"/usr/sbin/sendmail"}.
25012 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
25013 If non-empty, send mails via this SMTP host[:port] instead of
25015 Defaults to @samp{""}.
25018 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
25019 Subject: header to use for rejection mails. You can use the same
25020 variables as for @samp{rejection-reason} below.
25021 Defaults to @samp{"Rejected: %s"}.
25024 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
25025 Human readable error message for rejection mails. You can use
25038 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
25041 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
25042 Delimiter character between local-part and detail in email
25044 Defaults to @samp{"+"}.
25047 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
25048 Header where the original recipient address (SMTP's RCPT TO:
25049 address) is taken from if not available elsewhere. With dovecot-lda -a
25050 parameter overrides this. A commonly used header for this is
25052 Defaults to @samp{""}.
25055 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
25056 Should saving a mail to a nonexistent mailbox automatically create
25058 Defaults to @samp{#f}.
25061 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
25062 Should automatically created mailboxes be also automatically
25064 Defaults to @samp{#f}.
25067 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
25068 Maximum IMAP command line length. Some clients generate very long
25069 command lines with huge mailboxes, so you may need to raise this if you
25070 get "Too long argument" or "IMAP command line too large" errors
25072 Defaults to @samp{64000}.
25075 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
25076 IMAP logout format string:
25079 total number of bytes read from client
25081 total number of bytes sent to client.
25083 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
25084 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@}"}.
25087 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
25088 Override the IMAP CAPABILITY response. If the value begins with '+',
25089 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
25090 Defaults to @samp{""}.
25093 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
25094 How long to wait between "OK Still here" notifications when client
25096 Defaults to @samp{"2 mins"}.
25099 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
25100 ID field names and values to send to clients. Using * as the value
25101 makes Dovecot use the default value. The following fields have default
25102 values currently: name, version, os, os-version, support-url,
25104 Defaults to @samp{""}.
25107 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
25108 ID fields sent by client to log. * means everything.
25109 Defaults to @samp{""}.
25112 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
25113 Workarounds for various client bugs:
25116 @item delay-newmail
25117 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
25118 CHECK commands. Some clients ignore them otherwise, for example OSX
25119 Mail (<v2.1). Outlook Express breaks more badly though, without this it
25120 may show user "Message no longer in server" errors. Note that OE6
25121 still breaks even with this workaround if synchronization is set to
25124 @item tb-extra-mailbox-sep
25125 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
25126 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
25127 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
25129 @item tb-lsub-flags
25130 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
25131 This makes Thunderbird realize they aren't selectable and show them
25132 greyed out, instead of only later giving "not selectable" popup error.
25134 Defaults to @samp{()}.
25137 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
25138 Host allowed in URLAUTH URLs sent by client. "*" allows all.
25139 Defaults to @samp{""}.
25143 Whew! Lots of configuration options. The nice thing about it though is
25144 that Guix has a complete interface to Dovecot's configuration
25145 language. This allows not only a nice way to declare configurations,
25146 but also offers reflective capabilities as well: users can write code to
25147 inspect and transform configurations from within Scheme.
25149 However, it could be that you just want to get a @code{dovecot.conf} up
25150 and running. In that case, you can pass an
25151 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
25152 @code{dovecot-service}. As its name indicates, an opaque configuration
25153 does not have easy reflective capabilities.
25155 Available @code{opaque-dovecot-configuration} fields are:
25157 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
25158 The dovecot package.
25161 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
25162 The contents of the @code{dovecot.conf}, as a string.
25165 For example, if your @code{dovecot.conf} is just the empty string, you
25166 could instantiate a dovecot service like this:
25169 (dovecot-service #:config
25170 (opaque-dovecot-configuration
25174 @subsubheading OpenSMTPD Service
25176 @deffn {Scheme Variable} opensmtpd-service-type
25177 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
25178 service, whose value should be an @code{opensmtpd-configuration} object
25179 as in this example:
25182 (service opensmtpd-service-type
25183 (opensmtpd-configuration
25184 (config-file (local-file "./my-smtpd.conf"))))
25188 @deftp {Data Type} opensmtpd-configuration
25189 Data type representing the configuration of opensmtpd.
25192 @item @code{package} (default: @var{opensmtpd})
25193 Package object of the OpenSMTPD SMTP server.
25195 @item @code{config-file} (default: @code{%default-opensmtpd-config-file})
25196 File-like object of the OpenSMTPD configuration file to use. By default
25197 it listens on the loopback network interface, and allows for mail from
25198 users and daemons on the local machine, as well as permitting email to
25199 remote servers. Run @command{man smtpd.conf} for more information.
25201 @item @code{setgid-commands?} (default: @code{#t})
25202 Make the following commands setgid to @code{smtpq} so they can be
25203 executed: @command{smtpctl}, @command{sendmail}, @command{send-mail},
25204 @command{makemap}, @command{mailq}, and @command{newaliases}.
25205 @xref{Setuid Programs}, for more information on setgid programs.
25209 @subsubheading Exim Service
25211 @cindex mail transfer agent (MTA)
25212 @cindex MTA (mail transfer agent)
25215 @deffn {Scheme Variable} exim-service-type
25216 This is the type of the @uref{https://exim.org, Exim} mail transfer
25217 agent (MTA), whose value should be an @code{exim-configuration} object
25218 as in this example:
25221 (service exim-service-type
25222 (exim-configuration
25223 (config-file (local-file "./my-exim.conf"))))
25227 In order to use an @code{exim-service-type} service you must also have a
25228 @code{mail-aliases-service-type} service present in your
25229 @code{operating-system} (even if it has no aliases).
25231 @deftp {Data Type} exim-configuration
25232 Data type representing the configuration of exim.
25235 @item @code{package} (default: @var{exim})
25236 Package object of the Exim server.
25238 @item @code{config-file} (default: @code{#f})
25239 File-like object of the Exim configuration file to use. If its value is
25240 @code{#f} then use the default configuration file from the package
25241 provided in @code{package}. The resulting configuration file is loaded
25242 after setting the @code{exim_user} and @code{exim_group} configuration
25248 @subsubheading Getmail service
25253 @deffn {Scheme Variable} getmail-service-type
25254 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
25255 mail retriever, whose value should be an @code{getmail-configuration}.
25258 Available @code{getmail-configuration} fields are:
25260 @deftypevr {@code{getmail-configuration} parameter} symbol name
25261 A symbol to identify the getmail service.
25263 Defaults to @samp{"unset"}.
25267 @deftypevr {@code{getmail-configuration} parameter} package package
25268 The getmail package to use.
25272 @deftypevr {@code{getmail-configuration} parameter} string user
25273 The user to run getmail as.
25275 Defaults to @samp{"getmail"}.
25279 @deftypevr {@code{getmail-configuration} parameter} string group
25280 The group to run getmail as.
25282 Defaults to @samp{"getmail"}.
25286 @deftypevr {@code{getmail-configuration} parameter} string directory
25287 The getmail directory to use.
25289 Defaults to @samp{"/var/lib/getmail/default"}.
25293 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
25294 The getmail configuration file to use.
25296 Available @code{getmail-configuration-file} fields are:
25298 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
25299 What mail account to retrieve mail from, and how to access that account.
25301 Available @code{getmail-retriever-configuration} fields are:
25303 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
25304 The type of mail retriever to use. Valid values include @samp{passwd}
25307 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
25311 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
25312 Username to login to the mail server with.
25314 Defaults to @samp{unset}.
25318 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
25319 Username to login to the mail server with.
25321 Defaults to @samp{unset}.
25325 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
25326 Port number to connect to.
25328 Defaults to @samp{#f}.
25332 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
25333 Override fields from passwd.
25335 Defaults to @samp{""}.
25339 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
25340 Override fields from passwd.
25342 Defaults to @samp{()}.
25346 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
25347 PEM-formatted key file to use for the TLS negotiation.
25349 Defaults to @samp{""}.
25353 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
25354 PEM-formatted certificate file to use for the TLS negotiation.
25356 Defaults to @samp{""}.
25360 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
25361 CA certificates to use.
25363 Defaults to @samp{""}.
25367 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
25368 Extra retriever parameters.
25370 Defaults to @samp{()}.
25376 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
25377 What to do with retrieved messages.
25379 Available @code{getmail-destination-configuration} fields are:
25381 @deftypevr {@code{getmail-destination-configuration} parameter} string type
25382 The type of mail destination. Valid values include @samp{Maildir},
25383 @samp{Mboxrd} and @samp{MDA_external}.
25385 Defaults to @samp{unset}.
25389 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
25390 The path option for the mail destination. The behaviour depends on the
25393 Defaults to @samp{""}.
25397 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
25398 Extra destination parameters
25400 Defaults to @samp{()}.
25406 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
25409 Available @code{getmail-options-configuration} fields are:
25411 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
25412 If set to @samp{0}, getmail will only print warnings and errors. A
25413 value of @samp{1} means that messages will be printed about retrieving
25414 and deleting messages. If set to @samp{2}, getmail will print messages
25415 about each of its actions.
25417 Defaults to @samp{1}.
25421 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
25422 If true, getmail will retrieve all available messages. Otherwise it
25423 will only retrieve messages it hasn't seen previously.
25425 Defaults to @samp{#t}.
25429 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
25430 If set to true, messages will be deleted from the server after
25431 retrieving and successfully delivering them. Otherwise, messages will
25432 be left on the server.
25434 Defaults to @samp{#f}.
25438 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
25439 Getmail will delete messages this number of days after seeing them, if
25440 they have been delivered. This means messages will be left on the
25441 server this number of days after delivering them. A value of @samp{0}
25442 disabled this feature.
25444 Defaults to @samp{0}.
25448 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
25449 Delete messages larger than this of bytes after retrieving them, even if
25450 the delete and delete-after options are disabled. A value of @samp{0}
25451 disables this feature.
25453 Defaults to @samp{0}.
25457 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
25458 Retrieve messages totalling up to this number of bytes before closing
25459 the session with the server. A value of @samp{0} disables this feature.
25461 Defaults to @samp{0}.
25465 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
25466 Don't retrieve messages larger than this number of bytes. A value of
25467 @samp{0} disables this feature.
25469 Defaults to @samp{0}.
25473 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
25474 If true, getmail will add a Delivered-To header to messages.
25476 Defaults to @samp{#t}.
25480 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
25481 If set, getmail adds a Received header to the messages.
25483 Defaults to @samp{#t}.
25487 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
25488 Getmail will record a log of its actions to the named file. A value of
25489 @samp{""} disables this feature.
25491 Defaults to @samp{""}.
25495 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
25496 If true, getmail will record a log of its actions using the system
25499 Defaults to @samp{#f}.
25503 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
25504 If true, getmail will log information about messages not retrieved and
25505 the reason for not retrieving them, as well as starting and ending
25508 Defaults to @samp{#f}.
25512 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
25513 Extra options to include.
25515 Defaults to @samp{()}.
25523 @deftypevr {@code{getmail-configuration} parameter} list idle
25524 A list of mailboxes that getmail should wait on the server for new mail
25525 notifications. This depends on the server supporting the IDLE
25528 Defaults to @samp{()}.
25532 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
25533 Environment variables to set for getmail.
25535 Defaults to @samp{()}.
25539 @subsubheading Mail Aliases Service
25541 @cindex email aliases
25542 @cindex aliases, for email addresses
25544 @deffn {Scheme Variable} mail-aliases-service-type
25545 This is the type of the service which provides @code{/etc/aliases},
25546 specifying how to deliver mail to users on this system.
25549 (service mail-aliases-service-type
25550 '(("postmaster" "bob")
25551 ("bob" "bob@@example.com" "bob@@example2.com")))
25555 The configuration for a @code{mail-aliases-service-type} service is an
25556 association list denoting how to deliver mail that comes to this
25557 system. Each entry is of the form @code{(alias addresses ...)}, with
25558 @code{alias} specifying the local alias and @code{addresses} specifying
25559 where to deliver this user's mail.
25561 The aliases aren't required to exist as users on the local system. In
25562 the above example, there doesn't need to be a @code{postmaster} entry in
25563 the @code{operating-system}'s @code{user-accounts} in order to deliver
25564 the @code{postmaster} mail to @code{bob} (which subsequently would
25565 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
25567 @subsubheading GNU Mailutils IMAP4 Daemon
25568 @cindex GNU Mailutils IMAP4 Daemon
25570 @deffn {Scheme Variable} imap4d-service-type
25571 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
25572 mailutils, GNU Mailutils Manual}), whose value should be an
25573 @code{imap4d-configuration} object as in this example:
25576 (service imap4d-service-type
25577 (imap4d-configuration
25578 (config-file (local-file "imap4d.conf"))))
25582 @deftp {Data Type} imap4d-configuration
25583 Data type representing the configuration of @command{imap4d}.
25586 @item @code{package} (default: @code{mailutils})
25587 The package that provides @command{imap4d}.
25589 @item @code{config-file} (default: @code{%default-imap4d-config-file})
25590 File-like object of the configuration file to use, by default it will listen
25591 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
25592 Mailutils Manual}, for details.
25597 @subsubheading Radicale Service
25601 @deffn {Scheme Variable} radicale-service-type
25602 This is the type of the @uref{https://radicale.org, Radicale} CalDAV/CardDAV
25603 server whose value should be a @code{radicale-configuration}.
25606 @deftp {Data Type} radicale-configuration
25607 Data type representing the configuration of @command{radicale}.
25610 @item @code{package} (default: @code{radicale})
25611 The package that provides @command{radicale}.
25613 @item @code{config-file} (default: @code{%default-radicale-config-file})
25614 File-like object of the configuration file to use, by default it will listen
25615 on TCP port 5232 of @code{localhost} and use the @code{htpasswd} file at
25616 @file{/var/lib/radicale/users} with no (@code{plain}) encryption.
25621 @node Messaging Services
25622 @subsection Messaging Services
25627 The @code{(gnu services messaging)} module provides Guix service
25628 definitions for messaging services. Currently it provides the following
25631 @subsubheading Prosody Service
25633 @deffn {Scheme Variable} prosody-service-type
25634 This is the type for the @uref{https://prosody.im, Prosody XMPP
25635 communication server}. Its value must be a @code{prosody-configuration}
25636 record as in this example:
25639 (service prosody-service-type
25640 (prosody-configuration
25641 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
25644 (int-component-configuration
25645 (hostname "conference.example.net")
25647 (mod-muc (mod-muc-configuration)))))
25650 (virtualhost-configuration
25651 (domain "example.net"))))))
25654 See below for details about @code{prosody-configuration}.
25658 By default, Prosody does not need much configuration. Only one
25659 @code{virtualhosts} field is needed: it specifies the domain you wish
25662 You can perform various sanity checks on the generated configuration
25663 with the @code{prosodyctl check} command.
25665 Prosodyctl will also help you to import certificates from the
25666 @code{letsencrypt} directory so that the @code{prosody} user can access
25667 them. See @url{https://prosody.im/doc/letsencrypt}.
25670 prosodyctl --root cert import /etc/letsencrypt/live
25673 The available configuration parameters follow. Each parameter
25674 definition is preceded by its type; for example, @samp{string-list foo}
25675 indicates that the @code{foo} parameter should be specified as a list of
25676 strings. Types starting with @code{maybe-} denote parameters that won't
25677 show up in @code{prosody.cfg.lua} when their value is left unspecified.
25679 There is also a way to specify the configuration as a string, if you
25680 have an old @code{prosody.cfg.lua} file that you want to port over from
25681 some other system; see the end for more details.
25683 The @code{file-object} type designates either a file-like object
25684 (@pxref{G-Expressions, file-like objects}) or a file name.
25686 @c The following documentation was initially generated by
25687 @c (generate-documentation) in (gnu services messaging). Manually maintained
25688 @c documentation is better, so we shouldn't hesitate to edit below as
25689 @c needed. However if the change you want to make to this documentation
25690 @c can be done in an automated way, it's probably easier to change
25691 @c (generate-documentation) than to make it below and have to deal with
25692 @c the churn as Prosody updates.
25694 Available @code{prosody-configuration} fields are:
25696 @deftypevr {@code{prosody-configuration} parameter} package prosody
25697 The Prosody package.
25700 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
25701 Location of the Prosody data storage directory. See
25702 @url{https://prosody.im/doc/configure}.
25703 Defaults to @samp{"/var/lib/prosody"}.
25706 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
25707 Additional plugin directories. They are searched in all the specified
25708 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
25709 Defaults to @samp{()}.
25712 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
25713 Every virtual host and component needs a certificate so that clients and
25714 servers can securely verify its identity. Prosody will automatically load
25715 certificates/keys from the directory specified here.
25716 Defaults to @samp{"/etc/prosody/certs"}.
25719 @deftypevr {@code{prosody-configuration} parameter} string-list admins
25720 This is a list of accounts that are admins for the server. Note that you
25721 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
25722 @url{https://prosody.im/doc/creating_accounts}.
25723 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
25724 Defaults to @samp{()}.
25727 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
25728 Enable use of libevent for better performance under high load. See
25729 @url{https://prosody.im/doc/libevent}.
25730 Defaults to @samp{#f}.
25733 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
25734 This is the list of modules Prosody will load on startup. It looks for
25735 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
25736 Documentation on modules can be found at:
25737 @url{https://prosody.im/doc/modules}.
25738 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
25741 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
25742 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
25743 should you want to disable them then add them to this list.
25744 Defaults to @samp{()}.
25747 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
25748 Path to a text file where the shared groups are defined. If this path is
25749 empty then @samp{mod_groups} does nothing. See
25750 @url{https://prosody.im/doc/modules/mod_groups}.
25751 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
25754 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
25755 Disable account creation by default, for security. See
25756 @url{https://prosody.im/doc/creating_accounts}.
25757 Defaults to @samp{#f}.
25760 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
25761 These are the SSL/TLS-related settings. Most of them are disabled so to
25762 use Prosody's defaults. If you do not completely understand these options, do
25763 not add them to your config, it is easy to lower the security of your server
25764 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
25766 Available @code{ssl-configuration} fields are:
25768 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
25769 This determines what handshake to use.
25772 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
25773 Path to your private key file.
25776 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
25777 Path to your certificate file.
25780 @deftypevr {@code{ssl-configuration} parameter} file-object capath
25781 Path to directory containing root certificates that you wish Prosody to
25782 trust when verifying the certificates of remote servers.
25783 Defaults to @samp{"/etc/ssl/certs"}.
25786 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
25787 Path to a file containing root certificates that you wish Prosody to trust.
25788 Similar to @code{capath} but with all certificates concatenated together.
25791 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
25792 A list of verification options (these mostly map to OpenSSL's
25793 @code{set_verify()} flags).
25796 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
25797 A list of general options relating to SSL/TLS@. These map to OpenSSL's
25798 @code{set_options()}. For a full list of options available in LuaSec, see the
25802 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
25803 How long a chain of certificate authorities to check when looking for a
25804 trusted root certificate.
25807 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
25808 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
25809 clients, and in what order.
25812 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
25813 A path to a file containing parameters for Diffie-Hellman key exchange. You
25814 can create such a file with:
25815 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
25818 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
25819 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
25820 @samp{"secp384r1"}.
25823 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
25824 A list of ``extra'' verification options.
25827 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
25828 Password for encrypted private keys.
25833 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
25834 Whether to force all client-to-server connections to be encrypted or not.
25835 See @url{https://prosody.im/doc/modules/mod_tls}.
25836 Defaults to @samp{#f}.
25839 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
25840 Set of mechanisms that will never be offered. See
25841 @url{https://prosody.im/doc/modules/mod_saslauth}.
25842 Defaults to @samp{("DIGEST-MD5")}.
25845 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
25846 Whether to force all server-to-server connections to be encrypted or not.
25847 See @url{https://prosody.im/doc/modules/mod_tls}.
25848 Defaults to @samp{#f}.
25851 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
25852 Whether to require encryption and certificate authentication. This
25853 provides ideal security, but requires servers you communicate with to support
25854 encryption AND present valid, trusted certificates. See
25855 @url{https://prosody.im/doc/s2s#security}.
25856 Defaults to @samp{#f}.
25859 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
25860 Many servers don't support encryption or have invalid or self-signed
25861 certificates. You can list domains here that will not be required to
25862 authenticate using certificates. They will be authenticated using DNS@. See
25863 @url{https://prosody.im/doc/s2s#security}.
25864 Defaults to @samp{()}.
25867 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
25868 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
25869 valid certificates for some domains by specifying a list here. See
25870 @url{https://prosody.im/doc/s2s#security}.
25871 Defaults to @samp{()}.
25874 @deftypevr {@code{prosody-configuration} parameter} string authentication
25875 Select the authentication backend to use. The default provider stores
25876 passwords in plaintext and uses Prosody's configured data storage to store the
25877 authentication data. If you do not trust your server please see
25878 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
25879 about using the hashed backend. See also
25880 @url{https://prosody.im/doc/authentication}
25881 Defaults to @samp{"internal_plain"}.
25884 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
25885 Set logging options. Advanced logging configuration is not yet supported
25886 by the Prosody service. See @url{https://prosody.im/doc/logging}.
25887 Defaults to @samp{"*syslog"}.
25890 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
25891 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
25892 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
25895 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
25896 Maximum allowed size of the HTTP body (in bytes).
25899 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
25900 Some modules expose their own URL in various ways. This URL is built
25901 from the protocol, host and port used. If Prosody sits behind a proxy, the
25902 public URL will be @code{http-external-url} instead. See
25903 @url{https://prosody.im/doc/http#external_url}.
25906 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
25907 A host in Prosody is a domain on which user accounts can be created. For
25908 example if you want your users to have addresses like
25909 @samp{"john.smith@@example.com"} then you need to add a host
25910 @samp{"example.com"}. All options in this list will apply only to this host.
25913 The name @emph{virtual} host is used in configuration to avoid confusion with
25914 the actual physical host that Prosody is installed on. A single Prosody
25915 instance can serve many domains, each one defined as a VirtualHost entry in
25916 Prosody's configuration. Conversely a server that hosts a single domain would
25917 have just one VirtualHost entry.
25919 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
25922 Available @code{virtualhost-configuration} fields are:
25924 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:
25925 @deftypevr {@code{virtualhost-configuration} parameter} string domain
25926 Domain you wish Prosody to serve.
25931 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
25932 Components are extra services on a server which are available to clients,
25933 usually on a subdomain of the main server (such as
25934 @samp{"mycomponent.example.com"}). Example components might be chatroom
25935 servers, user directories, or gateways to other protocols.
25937 Internal components are implemented with Prosody-specific plugins. To add an
25938 internal component, you simply fill the hostname field, and the plugin you wish
25939 to use for the component.
25941 See @url{https://prosody.im/doc/components}.
25942 Defaults to @samp{()}.
25944 Available @code{int-component-configuration} fields are:
25946 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:
25947 @deftypevr {@code{int-component-configuration} parameter} string hostname
25948 Hostname of the component.
25951 @deftypevr {@code{int-component-configuration} parameter} string plugin
25952 Plugin you wish to use for the component.
25955 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
25956 Multi-user chat (MUC) is Prosody's module for allowing you to create
25957 hosted chatrooms/conferences for XMPP users.
25959 General information on setting up and using multi-user chatrooms can be found
25960 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
25961 which you should read if you are new to XMPP chatrooms.
25963 See also @url{https://prosody.im/doc/modules/mod_muc}.
25965 Available @code{mod-muc-configuration} fields are:
25967 @deftypevr {@code{mod-muc-configuration} parameter} string name
25968 The name to return in service discovery responses.
25969 Defaults to @samp{"Prosody Chatrooms"}.
25972 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
25973 If @samp{#t}, this will only allow admins to create new chatrooms.
25974 Otherwise anyone can create a room. The value @samp{"local"} restricts room
25975 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
25976 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
25977 restricts to service administrators only.
25978 Defaults to @samp{#f}.
25981 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
25982 Maximum number of history messages that will be sent to the member that has
25983 just joined the room.
25984 Defaults to @samp{20}.
25991 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
25992 External components use XEP-0114, which most standalone components
25993 support. To add an external component, you simply fill the hostname field. See
25994 @url{https://prosody.im/doc/components}.
25995 Defaults to @samp{()}.
25997 Available @code{ext-component-configuration} fields are:
25999 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:
26000 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
26001 Password which the component will use to log in.
26004 @deftypevr {@code{ext-component-configuration} parameter} string hostname
26005 Hostname of the component.
26010 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
26011 Port(s) Prosody listens on for component connections.
26012 Defaults to @samp{(5347)}.
26015 @deftypevr {@code{prosody-configuration} parameter} string component-interface
26016 Interface Prosody listens on for component connections.
26017 Defaults to @samp{"127.0.0.1"}.
26020 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
26021 Raw content that will be added to the configuration file.
26024 It could be that you just want to get a @code{prosody.cfg.lua}
26025 up and running. In that case, you can pass an
26026 @code{opaque-prosody-configuration} record as the value of
26027 @code{prosody-service-type}. As its name indicates, an opaque configuration
26028 does not have easy reflective capabilities.
26029 Available @code{opaque-prosody-configuration} fields are:
26031 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
26032 The prosody package.
26035 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
26036 The contents of the @code{prosody.cfg.lua} to use.
26039 For example, if your @code{prosody.cfg.lua} is just the empty
26040 string, you could instantiate a prosody service like this:
26043 (service prosody-service-type
26044 (opaque-prosody-configuration
26045 (prosody.cfg.lua "")))
26048 @c end of Prosody auto-generated documentation
26050 @subsubheading BitlBee Service
26052 @cindex IRC (Internet Relay Chat)
26053 @cindex IRC gateway
26054 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
26055 interface to a variety of messaging protocols such as XMPP.
26057 @defvr {Scheme Variable} bitlbee-service-type
26058 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
26059 gateway daemon. Its value is a @code{bitlbee-configuration} (see
26062 To have BitlBee listen on port 6667 on localhost, add this line to your
26066 (service bitlbee-service-type)
26070 @deftp {Data Type} bitlbee-configuration
26071 This is the configuration for BitlBee, with the following fields:
26074 @item @code{interface} (default: @code{"127.0.0.1"})
26075 @itemx @code{port} (default: @code{6667})
26076 Listen on the network interface corresponding to the IP address
26077 specified in @var{interface}, on @var{port}.
26079 When @var{interface} is @code{127.0.0.1}, only local clients can
26080 connect; when it is @code{0.0.0.0}, connections can come from any
26081 networking interface.
26083 @item @code{bitlbee} (default: @code{bitlbee})
26084 The BitlBee package to use.
26086 @item @code{plugins} (default: @code{'()})
26087 List of plugin packages to use---e.g., @code{bitlbee-discord}.
26089 @item @code{extra-settings} (default: @code{""})
26090 Configuration snippet added as-is to the BitlBee configuration file.
26094 @subsubheading Quassel Service
26096 @cindex IRC (Internet Relay Chat)
26097 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
26098 meaning that one or more clients can attach to and detach from the
26101 @defvr {Scheme Variable} quassel-service-type
26102 This is the service type for the @url{https://quassel-irc.org/,Quassel}
26103 IRC backend daemon. Its value is a @code{quassel-configuration}
26107 @deftp {Data Type} quassel-configuration
26108 This is the configuration for Quassel, with the following fields:
26111 @item @code{quassel} (default: @code{quassel})
26112 The Quassel package to use.
26114 @item @code{interface} (default: @code{"::,0.0.0.0"})
26115 @item @code{port} (default: @code{4242})
26116 Listen on the network interface(s) corresponding to the IPv4 or IPv6
26117 interfaces specified in the comma delimited @var{interface}, on
26120 @item @code{loglevel} (default: @code{"Info"})
26121 The level of logging desired. Accepted values are Debug, Info, Warning
26126 @node Telephony Services
26127 @subsection Telephony Services
26129 @cindex telephony, services
26130 The @code{(gnu services telephony)} module contains Guix service
26131 definitions for telephony services. Currently it provides the following
26134 @subsubheading Jami
26136 @cindex jami, service
26138 This section describes how to configure a Jami server that can be used
26139 to host video (or audio) conferences, among other uses. The following
26140 example demonstrates how to specify Jami account archives (backups) to
26141 be provisioned automatically:
26144 (service jami-service-type
26145 (jami-configuration
26147 (list (jami-account
26148 (archive "/etc/jami/unencrypted-account-1.gz"))
26150 (archive "/etc/jami/unencrypted-account-2.gz"))))))
26153 When the accounts field is specified, the Jami account files of the
26154 service found under @file{/var/lib/jami} are recreated every time the
26157 Jami accounts and their corresponding backup archives can be generated
26158 using the @code{jami} or @code{jami-gnome} Jami clients. The accounts
26159 should not be password-protected, but it is wise to ensure their files
26160 are only readable by @samp{root}.
26162 The next example shows how to declare that only some contacts should be
26163 allowed to communicate with a given account:
26166 (service jami-service-type
26167 (jami-configuration
26169 (list (jami-account
26170 (archive "/etc/jami/unencrypted-account-1.gz")
26171 (peer-discovery? #t)
26172 (rendezvous-point? #t)
26174 '("1dbcb0f5f37324228235564b79f2b9737e9a008f"
26175 "2dbcb0f5f37324228235564b79f2b9737e9a008f")))))))
26178 In this mode, only the declared @code{allowed-contacts} can initiate
26179 communication with the Jami account. This can be used, for example,
26180 with rendezvous point accounts to create a private video conferencing
26183 To put the system administrator in full control of the conferences
26184 hosted on their system, the Jami service supports the following actions:
26187 # herd doc jami list-actions
26189 list-account-details
26190 list-banned-contacts
26199 The above actions aim to provide the most valuable actions for
26200 moderation purposes, not to cover the whole Jami API. Users wanting to
26201 interact with the Jami daemon from Guile may be interested in
26202 experimenting with the @code{(gnu build jami-service)} module, which
26203 powers the above Shepherd actions.
26205 @c TODO: This should be auto-generated from the doc already defined on
26206 @c the shepherd-actions themselves in (gnu services telephony).
26207 The @code{add-moderator} and @code{ban-contact} actions accept a contact
26208 @emph{fingerprint} (40 characters long hash) as first argument and an
26209 account fingerprint or username as second argument:
26212 # herd add-moderator jami 1dbcb0f5f37324228235564b79f2b9737e9a008f \
26213 f3345f2775ddfe07a4b0d95daea111d15fbc1199
26215 # herd list-moderators jami
26216 Moderators for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
26217 - 1dbcb0f5f37324228235564b79f2b9737e9a008f
26221 In the case of @code{ban-contact}, the second username argument is
26222 optional; when omitted, the account is banned from all Jami accounts:
26225 # herd ban-contact jami 1dbcb0f5f37324228235564b79f2b9737e9a008f
26227 # herd list-banned-contacts jami
26228 Banned contacts for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
26229 - 1dbcb0f5f37324228235564b79f2b9737e9a008f
26233 Banned contacts are also stripped from their moderation privileges.
26235 The @code{disable-account} action allows to completely disconnect an
26236 account from the network, making it unreachable, while
26237 @code{enable-account} does the inverse. They accept a single account
26238 username or fingerprint as first argument:
26241 # herd disable-account jami f3345f2775ddfe07a4b0d95daea111d15fbc1199
26243 # herd list-accounts jami
26244 The following Jami accounts are available:
26245 - f3345f2775ddfe07a4b0d95daea111d15fbc1199 (dummy) [disabled]
26249 The @code{list-account-details} action prints the detailed parameters of
26250 each accounts in the Recutils format, which means the @command{recsel}
26251 command can be used to select accounts of interest (@pxref{Selection
26252 Expressions,,,recutils, GNU recutils manual}). Note that period
26253 characters (@samp{.}) found in the account parameter keys are mapped to
26254 underscores (@samp{_}) in the output, to meet the requirements of the
26255 Recutils format. The following example shows how to print the account
26256 fingerprints for all accounts operating in the rendezvous point mode:
26259 # herd list-account-details jami | \
26260 recsel -p Account.username -e 'Account.rendezVous ~ "true"'
26261 Account_username: f3345f2775ddfe07a4b0d95daea111d15fbc1199
26264 The remaining actions should be self-explanatory.
26266 The complete set of available configuration options is detailed below.
26268 @c TODO: Ideally, the following fragments would be auto-generated at
26269 @c build time, so that they needn't be manually duplicated.
26270 @c Auto-generated via (configuration->documentation 'jami-configuration)
26271 @deftp {Data Type} jami-configuration
26272 Available @code{jami-configuration} fields are:
26275 @item @code{libjami} (default: @code{libjami}) (type: package)
26276 The Jami daemon package to use.
26278 @item @code{dbus} (default: @code{dbus-for-jami}) (type: package)
26279 The D-Bus package to use to start the required D-Bus session.
26281 @item @code{nss-certs} (default: @code{nss-certs}) (type: package)
26282 The nss-certs package to use to provide TLS certificates.
26284 @item @code{enable-logging?} (default: @code{#t}) (type: boolean)
26285 Whether to enable logging to syslog.
26287 @item @code{debug?} (default: @code{#f}) (type: boolean)
26288 Whether to enable debug level messages.
26290 @item @code{auto-answer?} (default: @code{#f}) (type: boolean)
26291 Whether to force automatic answer to incoming calls.
26293 @item @code{accounts} (type: maybe-jami-account-list)
26294 A list of Jami accounts to be (re-)provisioned every time the Jami
26295 daemon service starts. When providing this field, the account
26296 directories under @file{/var/lib/jami/} are recreated every time the
26297 service starts, ensuring a consistent state.
26303 @c Auto-generated via (configuration->documentation 'jami-account)
26304 @deftp {Data Type} jami-account
26305 Available @code{jami-account} fields are:
26308 @item @code{archive} (type: string-or-computed-file)
26309 The account archive (backup) file name of the account. This is used to
26310 provision the account when the service starts. The account archive
26311 should @emph{not} be encrypted. It is highly recommended to make it
26312 readable only to the @samp{root} user (i.e., not in the store), to guard
26313 against leaking the secret key material of the Jami account it contains.
26315 @item @code{allowed-contacts} (type: maybe-account-fingerprint-list)
26316 The list of allowed contacts for the account, entered as their 40
26317 characters long fingerprint. Messages or calls from accounts not in
26318 that list will be rejected. When left specified, the configuration of
26319 the account archive is used as-is with respect to contacts and public
26320 inbound calls/messaging allowance, which typically defaults to allow any
26321 contact to communicate with the account.
26323 @item @code{moderators} (type: maybe-account-fingerprint-list)
26324 The list of contacts that should have moderation privileges (to ban,
26325 mute, etc. other users) in rendezvous conferences, entered as their 40
26326 characters long fingerprint. When left unspecified, the configuration
26327 of the account archive is used as-is with respect to moderation, which
26328 typically defaults to allow anyone to moderate.
26330 @item @code{rendezvous-point?} (type: maybe-boolean)
26331 Whether the account should operate in the rendezvous mode. In this
26332 mode, all the incoming audio/video calls are mixed into a conference.
26333 When left unspecified, the value from the account archive prevails.
26335 @item @code{peer-discovery?} (type: maybe-boolean)
26336 Whether peer discovery should be enabled. Peer discovery is used to
26337 discover other OpenDHT nodes on the local network, which can be useful
26338 to maintain communication between devices on such network even when the
26339 connection to the the Internet has been lost. When left unspecified,
26340 the value from the account archive prevails.
26342 @item @code{bootstrap-hostnames} (type: maybe-string-list)
26343 A list of hostnames or IPs pointing to OpenDHT nodes, that should be
26344 used to initially join the OpenDHT network. When left unspecified, the
26345 value from the account archive prevails.
26347 @item @code{name-server-uri} (type: maybe-string)
26348 The URI of the name server to use, that can be used to retrieve the
26349 account fingerprint for a registered username.
26355 @subsubheading Mumble server
26359 @cindex VoIP server
26360 This section describes how to set up and run a
26361 @uref{https://mumble.info, Mumble} server (formerly known as Murmur).
26363 @deftp {Data Type} mumble-server-configuration
26364 The service type for the Mumble server. An example configuration can
26368 (service mumble-server-service-type
26369 (mumble-server-configuration
26371 "Welcome to this Mumble server running on Guix!")
26372 (cert-required? #t) ;disallow text password logins
26373 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
26374 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
26377 After reconfiguring your system, you can manually set the mumble-server
26379 password with the command that is printed during the activation phase.
26381 It is recommended to register a normal Mumble user account
26382 and grant it admin or moderator rights.
26383 You can use the @code{mumble} client to
26384 login as new normal user, register yourself, and log out.
26385 For the next step login with the name @code{SuperUser} use
26386 the @code{SuperUser} password that you set previously,
26387 and grant your newly registered mumble user administrator or moderator
26388 rights and create some channels.
26390 Available @code{mumble-server-configuration} fields are:
26393 @item @code{package} (default: @code{mumble})
26394 Package that contains @code{bin/mumble-server}.
26396 @item @code{user} (default: @code{"mumble-server"})
26397 User who will run the Mumble-Server server.
26399 @item @code{group} (default: @code{"mumble-server"})
26400 Group of the user who will run the mumble-server server.
26402 @item @code{port} (default: @code{64738})
26403 Port on which the server will listen.
26405 @item @code{welcome-text} (default: @code{""})
26406 Welcome text sent to clients when they connect.
26408 @item @code{server-password} (default: @code{""})
26409 Password the clients have to enter in order to connect.
26411 @item @code{max-users} (default: @code{100})
26412 Maximum of users that can be connected to the server at once.
26414 @item @code{max-user-bandwidth} (default: @code{#f})
26415 Maximum voice traffic a user can send per second.
26417 @item @code{database-file} (default: @code{"/var/lib/mumble-server/db.sqlite"})
26418 File name of the sqlite database.
26419 The service's user will become the owner of the directory.
26421 @item @code{log-file} (default: @code{"/var/log/mumble-server/mumble-server.log"})
26422 File name of the log file.
26423 The service's user will become the owner of the directory.
26425 @item @code{autoban-attempts} (default: @code{10})
26426 Maximum number of logins a user can make in @code{autoban-timeframe}
26427 without getting auto banned for @code{autoban-time}.
26429 @item @code{autoban-timeframe} (default: @code{120})
26430 Timeframe for autoban in seconds.
26432 @item @code{autoban-time} (default: @code{300})
26433 Amount of time in seconds for which a client gets banned
26434 when violating the autoban limits.
26436 @item @code{opus-threshold} (default: @code{100})
26437 Percentage of clients that need to support opus
26438 before switching over to opus audio codec.
26440 @item @code{channel-nesting-limit} (default: @code{10})
26441 How deep channels can be nested at maximum.
26443 @item @code{channelname-regex} (default: @code{#f})
26444 A string in form of a Qt regular expression that channel names must conform to.
26446 @item @code{username-regex} (default: @code{#f})
26447 A string in form of a Qt regular expression that user names must conform to.
26449 @item @code{text-message-length} (default: @code{5000})
26450 Maximum size in bytes that a user can send in one text chat message.
26452 @item @code{image-message-length} (default: @code{(* 128 1024)})
26453 Maximum size in bytes that a user can send in one image message.
26455 @item @code{cert-required?} (default: @code{#f})
26456 If it is set to @code{#t} clients that use weak password authentication
26457 will not be accepted. Users must have completed the certificate wizard to join.
26459 @item @code{remember-channel?} (default: @code{#f})
26460 Should mumble-server remember the last channel each user was in when
26461 they disconnected and put them into the remembered channel when they
26464 @item @code{allow-html?} (default: @code{#f})
26465 Should html be allowed in text messages, user comments, and channel descriptions.
26467 @item @code{allow-ping?} (default: @code{#f})
26468 Setting to true exposes the current user count, the maximum user count, and
26469 the server's maximum bandwidth per client to unauthenticated users. In the
26470 Mumble client, this information is shown in the Connect dialog.
26472 Disabling this setting will prevent public listing of the server.
26474 @item @code{bonjour?} (default: @code{#f})
26475 Should the server advertise itself in the local network through the bonjour protocol.
26477 @item @code{send-version?} (default: @code{#f})
26478 Should the mumble-server server version be exposed in ping requests.
26480 @item @code{log-days} (default: @code{31})
26481 Mumble also stores logs in the database, which are accessible via RPC.
26482 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
26483 or -1 to disable logging to the database.
26485 @item @code{obfuscate-ips?} (default: @code{#t})
26486 Should logged ips be obfuscated to protect the privacy of users.
26488 @item @code{ssl-cert} (default: @code{#f})
26489 File name of the SSL/TLS certificate used for encrypted connections.
26492 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
26494 @item @code{ssl-key} (default: @code{#f})
26495 Filepath to the ssl private key used for encrypted connections.
26497 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
26500 @item @code{ssl-dh-params} (default: @code{#f})
26501 File name of a PEM-encoded file with Diffie-Hellman parameters
26502 for the SSL/TLS encryption. Alternatively you set it to
26503 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
26504 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
26506 @item @code{ssl-ciphers} (default: @code{#f})
26507 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
26510 This option is specified using
26511 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
26512 OpenSSL cipher list notation}.
26514 It is recommended that you try your cipher string using
26515 'openssl ciphers <string>' before setting it here, to get a feel for
26516 which cipher suites you will get.
26517 After setting this option, it is recommend that you inspect your Mumble
26518 server log to ensure that Mumble is using the cipher suites that you
26522 Changing this option may impact the backwards compatibility of your
26523 Mumble-Server server, and can remove the ability for older Mumble clients to be able to connect to it.
26526 @item @code{public-registration} (default: @code{#f})
26527 Must be a @code{<mumble-server-public-registration-configuration>}
26528 record or @code{#f}.
26530 You can optionally register your server in the public server list that the
26531 @code{mumble} client shows on startup.
26532 You cannot register your server if you have set a @code{server-password},
26533 or set @code{allow-ping} to @code{#f}.
26535 It might take a few hours until it shows up in the public list.
26537 @item @code{file} (default: @code{#f})
26538 Optional alternative override for this configuration.
26542 @deftp {Data Type} mumble-server-public-registration-configuration
26543 Configuration for public registration of a mumble-server service.
26547 This is a display name for your server. Not to be confused with the hostname.
26549 @item @code{password}
26550 A password to identify your registration.
26551 Subsequent updates will need the same password. Don't lose your password.
26554 This should be a @code{http://} or @code{https://} link to your web
26557 @item @code{hostname} (default: @code{#f})
26558 By default your server will be listed by its IP address.
26559 If it is set your server will be linked by this host name instead.
26563 @quotation Deprecation notice
26564 Due to historical reasons, all of the above @code{mumble-server-}
26565 procedures are also exported with the @code{murmur-} prefix.
26566 It is recommended that you switch to using @code{mumble-server-}
26570 @node File-Sharing Services
26571 @subsection File-Sharing Services
26573 The @code{(gnu services file-sharing)} module provides services that
26574 assist with transferring files over peer-to-peer file-sharing networks.
26576 @subsubheading Transmission Daemon Service
26578 @uref{https://transmissionbt.com/, Transmission} is a flexible
26579 BitTorrent client that offers a variety of graphical and command-line
26580 interfaces. A @code{transmission-daemon-service-type} service provides
26581 Transmission's headless variant, @command{transmission-daemon}, as a
26582 system service, allowing users to share files via BitTorrent even when
26583 they are not logged in.
26585 @deffn {Scheme Variable} transmission-daemon-service-type
26586 The service type for the Transmission Daemon BitTorrent client. Its
26587 value must be a @code{transmission-daemon-configuration} object as in
26591 (service transmission-daemon-service-type
26592 (transmission-daemon-configuration
26593 ;; Restrict access to the RPC ("control") interface
26594 (rpc-authentication-required? #t)
26595 (rpc-username "transmission")
26597 (transmission-password-hash
26598 "transmission" ; desired password
26599 "uKd1uMs9")) ; arbitrary salt value
26601 ;; Accept requests from this and other hosts on the
26603 (rpc-whitelist-enabled? #t)
26604 (rpc-whitelist '("::1" "127.0.0.1" "192.168.0.*"))
26606 ;; Limit bandwidth use during work hours
26607 (alt-speed-down (* 1024 2)) ; 2 MB/s
26608 (alt-speed-up 512) ; 512 kB/s
26610 (alt-speed-time-enabled? #t)
26611 (alt-speed-time-day 'weekdays)
26612 (alt-speed-time-begin
26613 (+ (* 60 8) 30)) ; 8:30 am
26614 (alt-speed-time-end
26615 (+ (* 60 (+ 12 5)) 30)))) ; 5:30 pm
26619 Once the service is started, users can interact with the daemon through
26620 its Web interface (at @code{http://localhost:9091/}) or by using the
26621 @command{transmission-remote} command-line tool, available in the
26622 @code{transmission} package. (Emacs users may want to also consider the
26623 @code{emacs-transmission} package.) Both communicate with the daemon
26624 through its remote procedure call (RPC) interface, which by default is
26625 available to all users on the system; you may wish to change this by
26626 assigning values to the @code{rpc-authentication-required?},
26627 @code{rpc-username} and @code{rpc-password} settings, as shown in the
26628 example above and documented further below.
26630 The value for @code{rpc-password} must be a password hash of the type
26631 generated and used by Transmission clients. This can be copied verbatim
26632 from an existing @file{settings.json} file, if another Transmission
26633 client is already being used. Otherwise, the
26634 @code{transmission-password-hash} and @code{transmission-random-salt}
26635 procedures provided by this module can be used to obtain a suitable hash
26638 @deffn {Scheme Procedure} transmission-password-hash @var{password} @var{salt}
26639 Returns a string containing the result of hashing @var{password}
26640 together with @var{salt}, in the format recognized by Transmission
26641 clients for their @code{rpc-password} configuration setting.
26643 @var{salt} must be an eight-character string. The
26644 @code{transmission-random-salt} procedure can be used to generate a
26645 suitable salt value at random.
26648 @deffn {Scheme Procedure} transmission-random-salt
26649 Returns a string containing a random, eight-character salt value of the
26650 type generated and used by Transmission clients, suitable for passing to
26651 the @code{transmission-password-hash} procedure.
26654 These procedures are accessible from within a Guile REPL started with
26655 the @command{guix repl} command (@pxref{Invoking guix repl}). This is
26656 useful for obtaining a random salt value to provide as the second
26657 parameter to `transmission-password-hash`, as in this example session:
26661 scheme@@(guix-user)> ,use (gnu services file-sharing)
26662 scheme@@(guix-user)> (transmission-random-salt)
26666 Alternatively, a complete password hash can generated in a single step:
26669 scheme@@(guix-user)> (transmission-password-hash "transmission"
26670 (transmission-random-salt))
26671 $2 = "@{c8bbc6d1740cd8dc819a6e25563b67812c1c19c9VtFPfdsX"
26674 The resulting string can be used as-is for the value of
26675 @code{rpc-password}, allowing the password to be kept hidden even in the
26676 operating-system configuration.
26678 Torrent files downloaded by the daemon are directly accessible only to
26679 users in the ``transmission'' user group, who receive read-only access
26680 to the directory specified by the @code{download-dir} configuration
26681 setting (and also the directory specified by @code{incomplete-dir}, if
26682 @code{incomplete-dir-enabled?} is @code{#t}). Downloaded files can be
26683 moved to another directory or deleted altogether using
26684 @command{transmission-remote} with its @code{--move} and
26685 @code{--remove-and-delete} options.
26687 If the @code{watch-dir-enabled?} setting is set to @code{#t}, users in
26688 the ``transmission'' group are able also to place @file{.torrent} files
26689 in the directory specified by @code{watch-dir} to have the corresponding
26690 torrents added by the daemon. (The @code{trash-original-torrent-files?}
26691 setting controls whether the daemon deletes these files after processing
26694 Some of the daemon's configuration settings can be changed temporarily
26695 by @command{transmission-remote} and similar tools. To undo these
26696 changes, use the service's @code{reload} action to have the daemon
26697 reload its settings from disk:
26700 # herd reload transmission-daemon
26703 The full set of available configuration settings is defined by the
26704 @code{transmission-daemon-configuration} data type.
26706 @deftp {Data Type} transmission-daemon-configuration
26707 The data type representing configuration settings for Transmission
26708 Daemon. These correspond directly to the settings recognized by
26709 Transmission clients in their @file{settings.json} file.
26712 @c The following documentation was initially generated by
26713 @c (generate-transmission-daemon-documentation) in (gnu services
26714 @c file-sharing). Manually maintained documentation is better, so we
26715 @c shouldn't hesitate to edit below as needed. However if the change
26716 @c you want to make to this documentation can be done in an automated
26717 @c way, it's probably easier to change (generate-documentation) than to
26718 @c make it below and have to deal with the churn as Transmission Daemon
26721 @c %start of fragment
26723 Available @code{transmission-daemon-configuration} fields are:
26725 @deftypevr {@code{transmission-daemon-configuration} parameter} package transmission
26726 The Transmission package to use.
26730 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer stop-wait-period
26731 The period, in seconds, to wait when stopping the service for
26732 @command{transmission-daemon} to exit before killing its process. This
26733 allows the daemon time to complete its housekeeping and send a final
26734 update to trackers as it shuts down. On slow hosts, or hosts with a
26735 slow network connection, this value may need to be increased.
26737 Defaults to @samp{10}.
26741 @deftypevr {@code{transmission-daemon-configuration} parameter} string download-dir
26742 The directory to which torrent files are downloaded.
26744 Defaults to @samp{"/var/lib/transmission-daemon/downloads"}.
26748 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean incomplete-dir-enabled?
26749 If @code{#t}, files will be held in @code{incomplete-dir} while their
26750 torrent is being downloaded, then moved to @code{download-dir} once the
26751 torrent is complete. Otherwise, files for all torrents (including those
26752 still being downloaded) will be placed in @code{download-dir}.
26754 Defaults to @samp{#f}.
26758 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string incomplete-dir
26759 The directory in which files from incompletely downloaded torrents will
26760 be held when @code{incomplete-dir-enabled?} is @code{#t}.
26762 Defaults to @samp{disabled}.
26766 @deftypevr {@code{transmission-daemon-configuration} parameter} umask umask
26767 The file mode creation mask used for downloaded files. (See the
26768 @command{umask} man page for more information.)
26770 Defaults to @samp{18}.
26774 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rename-partial-files?
26775 When @code{#t}, ``.part'' is appended to the name of partially
26778 Defaults to @samp{#t}.
26782 @deftypevr {@code{transmission-daemon-configuration} parameter} preallocation-mode preallocation
26783 The mode by which space should be preallocated for downloaded files, one
26784 of @code{none}, @code{fast} (or @code{sparse}) and @code{full}.
26785 Specifying @code{full} will minimize disk fragmentation at a cost to
26786 file-creation speed.
26788 Defaults to @samp{fast}.
26792 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean watch-dir-enabled?
26793 If @code{#t}, the directory specified by @code{watch-dir} will be
26794 watched for new @file{.torrent} files and the torrents they describe
26795 added automatically (and the original files removed, if
26796 @code{trash-original-torrent-files?} is @code{#t}).
26798 Defaults to @samp{#f}.
26802 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string watch-dir
26803 The directory to be watched for @file{.torrent} files indicating new
26804 torrents to be added, when @code{watch-dir-enabled} is @code{#t}.
26806 Defaults to @samp{disabled}.
26810 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean trash-original-torrent-files?
26811 When @code{#t}, @file{.torrent} files will be deleted from the watch
26812 directory once their torrent has been added (see
26813 @code{watch-directory-enabled?}).
26815 Defaults to @samp{#f}.
26819 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-down-enabled?
26820 When @code{#t}, the daemon's download speed will be limited to the rate
26821 specified by @code{speed-limit-down}.
26823 Defaults to @samp{#f}.
26827 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-down
26828 The default global-maximum download speed, in kilobytes per second.
26830 Defaults to @samp{100}.
26834 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-up-enabled?
26835 When @code{#t}, the daemon's upload speed will be limited to the rate
26836 specified by @code{speed-limit-up}.
26838 Defaults to @samp{#f}.
26842 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-up
26843 The default global-maximum upload speed, in kilobytes per second.
26845 Defaults to @samp{100}.
26849 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-enabled?
26850 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
26851 @code{alt-speed-up} are used (in place of @code{speed-limit-down} and
26852 @code{speed-limit-up}, if they are enabled) to constrain the daemon's
26853 bandwidth usage. This can be scheduled to occur automatically at
26854 certain times during the week; see @code{alt-speed-time-enabled?}.
26856 Defaults to @samp{#f}.
26860 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-down
26861 The alternate global-maximum download speed, in kilobytes per second.
26863 Defaults to @samp{50}.
26867 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-up
26868 The alternate global-maximum upload speed, in kilobytes per second.
26870 Defaults to @samp{50}.
26874 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-time-enabled?
26875 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
26876 @code{alt-speed-up} will be enabled automatically during the periods
26877 specified by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
26878 @code{alt-time-speed-end}.
26880 Defaults to @samp{#f}.
26884 @deftypevr {@code{transmission-daemon-configuration} parameter} day-list alt-speed-time-day
26885 The days of the week on which the alternate-speed schedule should be
26886 used, specified either as a list of days (@code{sunday}, @code{monday},
26887 and so on) or using one of the symbols @code{weekdays}, @code{weekends}
26890 Defaults to @samp{all}.
26894 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-begin
26895 The time of day at which to enable the alternate speed limits, expressed
26896 as a number of minutes since midnight.
26898 Defaults to @samp{540}.
26902 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-end
26903 The time of day at which to disable the alternate speed limits,
26904 expressed as a number of minutes since midnight.
26906 Defaults to @samp{1020}.
26910 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv4
26911 The IP address at which to listen for peer connections, or ``0.0.0.0''
26912 to listen at all available IP addresses.
26914 Defaults to @samp{"0.0.0.0"}.
26918 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv6
26919 The IPv6 address at which to listen for peer connections, or ``::'' to
26920 listen at all available IPv6 addresses.
26922 Defaults to @samp{"::"}.
26926 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean peer-port-random-on-start?
26927 If @code{#t}, when the daemon starts it will select a port at random on
26928 which to listen for peer connections, from the range specified
26929 (inclusively) by @code{peer-port-random-low} and
26930 @code{peer-port-random-high}. Otherwise, it listens on the port
26931 specified by @code{peer-port}.
26933 Defaults to @samp{#f}.
26937 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-low
26938 The lowest selectable port number when @code{peer-port-random-on-start?}
26941 Defaults to @samp{49152}.
26945 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-high
26946 The highest selectable port number when @code{peer-port-random-on-start}
26949 Defaults to @samp{65535}.
26953 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port
26954 The port on which to listen for peer connections when
26955 @code{peer-port-random-on-start?} is @code{#f}.
26957 Defaults to @samp{51413}.
26961 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean port-forwarding-enabled?
26962 If @code{#t}, the daemon will attempt to configure port-forwarding on an
26963 upstream gateway automatically using @acronym{UPnP} and
26966 Defaults to @samp{#t}.
26970 @deftypevr {@code{transmission-daemon-configuration} parameter} encryption-mode encryption
26971 The encryption preference for peer connections, one of
26972 @code{prefer-unencrypted-connections},
26973 @code{prefer-encrypted-connections} or
26974 @code{require-encrypted-connections}.
26976 Defaults to @samp{prefer-encrypted-connections}.
26980 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string peer-congestion-algorithm
26981 The TCP congestion-control algorithm to use for peer connections,
26982 specified using a string recognized by the operating system in calls to
26983 @code{setsockopt}. When left unspecified, the operating-system default
26986 Note that on GNU/Linux systems, the kernel must be configured to allow
26987 processes to use a congestion-control algorithm not in the default set;
26988 otherwise, it will deny these requests with ``Operation not permitted''.
26989 To see which algorithms are available on your system and which are
26990 currently permitted for use, look at the contents of the files
26991 @file{tcp_available_congestion_control} and
26992 @file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
26995 As an example, to have Transmission Daemon use
26996 @uref{http://www-ece.rice.edu/networks/TCP-LP/,the TCP Low Priority
26997 congestion-control algorithm}, you'll need to modify your kernel
26998 configuration to build in support for the algorithm, then update your
26999 operating-system configuration to allow its use by adding a
27000 @code{sysctl-service-type} service (or updating the existing one's
27001 configuration) with lines like the following:
27004 (service sysctl-service-type
27005 (sysctl-configuration
27007 ("net.ipv4.tcp_allowed_congestion_control" .
27008 "reno cubic lp"))))
27011 The Transmission Daemon configuration can then be updated with
27014 (peer-congestion-algorithm "lp")
27017 and the system reconfigured to have the changes take effect.
27019 Defaults to @samp{disabled}.
27023 @deftypevr {@code{transmission-daemon-configuration} parameter} tcp-type-of-service peer-socket-tos
27024 The type of service to request in outgoing @acronym{TCP} packets, one of
27025 @code{default}, @code{low-cost}, @code{throughput}, @code{low-delay} and
27026 @code{reliability}.
27028 Defaults to @samp{default}.
27032 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-global
27033 The global limit on the number of connected peers.
27035 Defaults to @samp{200}.
27039 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-per-torrent
27040 The per-torrent limit on the number of connected peers.
27042 Defaults to @samp{50}.
27046 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer upload-slots-per-torrent
27047 The maximum number of peers to which the daemon will upload data
27048 simultaneously for each torrent.
27050 Defaults to @samp{14}.
27054 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-id-ttl-hours
27055 The maximum lifespan, in hours, of the peer ID associated with each
27056 public torrent before it is regenerated.
27058 Defaults to @samp{6}.
27062 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean blocklist-enabled?
27063 When @code{#t}, the daemon will ignore peers mentioned in the blocklist
27064 it has most recently downloaded from @code{blocklist-url}.
27066 Defaults to @samp{#f}.
27070 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string blocklist-url
27071 The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
27072 @file{.dat} format) to be periodically downloaded and applied when
27073 @code{blocklist-enabled?} is @code{#t}.
27075 Defaults to @samp{disabled}.
27079 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean download-queue-enabled?
27080 If @code{#t}, the daemon will be limited to downloading at most
27081 @code{download-queue-size} non-stalled torrents simultaneously.
27083 Defaults to @samp{#t}.
27087 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer download-queue-size
27088 The size of the daemon's download queue, which limits the number of
27089 non-stalled torrents it will download at any one time when
27090 @code{download-queue-enabled?} is @code{#t}.
27092 Defaults to @samp{5}.
27096 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean seed-queue-enabled?
27097 If @code{#t}, the daemon will be limited to seeding at most
27098 @code{seed-queue-size} non-stalled torrents simultaneously.
27100 Defaults to @samp{#f}.
27104 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer seed-queue-size
27105 The size of the daemon's seed queue, which limits the number of
27106 non-stalled torrents it will seed at any one time when
27107 @code{seed-queue-enabled?} is @code{#t}.
27109 Defaults to @samp{10}.
27113 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean queue-stalled-enabled?
27114 When @code{#t}, the daemon will consider torrents for which it has not
27115 shared data in the past @code{queue-stalled-minutes} minutes to be
27116 stalled and not count them against its @code{download-queue-size} and
27117 @code{seed-queue-size} limits.
27119 Defaults to @samp{#t}.
27123 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer queue-stalled-minutes
27124 The maximum period, in minutes, a torrent may be idle before it is
27125 considered to be stalled, when @code{queue-stalled-enabled?} is
27128 Defaults to @samp{30}.
27132 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean ratio-limit-enabled?
27133 When @code{#t}, a torrent being seeded will automatically be paused once
27134 it reaches the ratio specified by @code{ratio-limit}.
27136 Defaults to @samp{#f}.
27140 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-rational ratio-limit
27141 The ratio at which a torrent being seeded will be paused, when
27142 @code{ratio-limit-enabled?} is @code{#t}.
27144 Defaults to @samp{2.0}.
27148 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean idle-seeding-limit-enabled?
27149 When @code{#t}, a torrent being seeded will automatically be paused once
27150 it has been idle for @code{idle-seeding-limit} minutes.
27152 Defaults to @samp{#f}.
27156 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer idle-seeding-limit
27157 The maximum period, in minutes, a torrent being seeded may be idle
27158 before it is paused, when @code{idle-seeding-limit-enabled?} is
27161 Defaults to @samp{30}.
27165 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean dht-enabled?
27166 Enable @uref{http://bittorrent.org/beps/bep_0005.html,the distributed
27167 hash table (@acronym{DHT}) protocol}, which supports the use of
27168 trackerless torrents.
27170 Defaults to @samp{#t}.
27174 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean lpd-enabled?
27175 Enable @uref{https://en.wikipedia.org/wiki/Local_Peer_Discovery,local
27176 peer discovery} (@acronym{LPD}), which allows the discovery of peers on
27177 the local network and may reduce the amount of data sent over the public
27180 Defaults to @samp{#f}.
27184 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean pex-enabled?
27185 Enable @uref{https://en.wikipedia.org/wiki/Peer_exchange,peer exchange}
27186 (@acronym{PEX}), which reduces the daemon's reliance on external
27187 trackers and may improve its performance.
27189 Defaults to @samp{#t}.
27193 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean utp-enabled?
27194 Enable @uref{http://bittorrent.org/beps/bep_0029.html,the micro
27195 transport protocol} (@acronym{uTP}), which aims to reduce the impact of
27196 BitTorrent traffic on other users of the local network while maintaining
27197 full utilization of the available bandwidth.
27199 Defaults to @samp{#t}.
27203 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-enabled?
27204 If @code{#t}, enable the remote procedure call (@acronym{RPC})
27205 interface, which allows remote control of the daemon via its Web
27206 interface, the @command{transmission-remote} command-line client, and
27209 Defaults to @samp{#t}.
27213 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-bind-address
27214 The IP address at which to listen for @acronym{RPC} connections, or
27215 ``0.0.0.0'' to listen at all available IP addresses.
27217 Defaults to @samp{"0.0.0.0"}.
27221 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number rpc-port
27222 The port on which to listen for @acronym{RPC} connections.
27224 Defaults to @samp{9091}.
27228 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-url
27229 The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.
27231 Defaults to @samp{"/transmission/"}.
27235 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-authentication-required?
27236 When @code{#t}, clients must authenticate (see @code{rpc-username} and
27237 @code{rpc-password}) when using the @acronym{RPC} interface. Note this
27238 has the side effect of disabling host-name whitelisting (see
27239 @code{rpc-host-whitelist-enabled?}.
27241 Defaults to @samp{#f}.
27245 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string rpc-username
27246 The username required by clients to access the @acronym{RPC} interface
27247 when @code{rpc-authentication-required?} is @code{#t}.
27249 Defaults to @samp{disabled}.
27253 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-transmission-password-hash rpc-password
27254 The password required by clients to access the @acronym{RPC} interface
27255 when @code{rpc-authentication-required?} is @code{#t}. This must be
27256 specified using a password hash in the format recognized by Transmission
27257 clients, either copied from an existing @file{settings.json} file or
27258 generated using the @code{transmission-password-hash} procedure.
27260 Defaults to @samp{disabled}.
27264 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-whitelist-enabled?
27265 When @code{#t}, @acronym{RPC} requests will be accepted only when they
27266 originate from an address specified in @code{rpc-whitelist}.
27268 Defaults to @samp{#t}.
27272 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-whitelist
27273 The list of IP and IPv6 addresses from which @acronym{RPC} requests will
27274 be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards
27275 may be specified using @samp{*}.
27277 Defaults to @samp{("127.0.0.1" "::1")}.
27281 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-host-whitelist-enabled?
27282 When @code{#t}, @acronym{RPC} requests will be accepted only when they
27283 are addressed to a host named in @code{rpc-host-whitelist}. Note that
27284 requests to ``localhost'' or ``localhost.'', or to a numeric address,
27285 are always accepted regardless of these settings.
27287 Note also this functionality is disabled when
27288 @code{rpc-authentication-required?} is @code{#t}.
27290 Defaults to @samp{#t}.
27294 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-host-whitelist
27295 The list of host names recognized by the @acronym{RPC} server when
27296 @code{rpc-host-whitelist-enabled?} is @code{#t}.
27298 Defaults to @samp{()}.
27302 @deftypevr {@code{transmission-daemon-configuration} parameter} message-level message-level
27303 The minimum severity level of messages to be logged (to
27304 @file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
27305 logging), @code{error}, @code{info} and @code{debug}.
27307 Defaults to @samp{info}.
27311 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean start-added-torrents?
27312 When @code{#t}, torrents are started as soon as they are added;
27313 otherwise, they are added in ``paused'' state.
27315 Defaults to @samp{#t}.
27319 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean script-torrent-done-enabled?
27320 When @code{#t}, the script specified by
27321 @code{script-torrent-done-filename} will be invoked each time a torrent
27324 Defaults to @samp{#f}.
27328 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-file-object script-torrent-done-filename
27329 A file name or file-like object specifying a script to run each time a
27330 torrent completes, when @code{script-torrent-done-enabled?} is
27333 Defaults to @samp{disabled}.
27337 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean scrape-paused-torrents-enabled?
27338 When @code{#t}, the daemon will scrape trackers for a torrent even when
27339 the torrent is paused.
27341 Defaults to @samp{#t}.
27345 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer cache-size-mb
27346 The amount of memory, in megabytes, to allocate for the daemon's
27347 in-memory cache. A larger value may increase performance by reducing
27348 the frequency of disk I/O.
27350 Defaults to @samp{4}.
27354 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean prefetch-enabled?
27355 When @code{#t}, the daemon will try to improve I/O performance by
27356 hinting to the operating system which data is likely to be read next
27357 from disk to satisfy requests from peers.
27359 Defaults to @samp{#t}.
27364 @c %end of fragment
27368 @node Monitoring Services
27369 @subsection Monitoring Services
27371 @subsubheading Tailon Service
27373 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
27374 viewing and searching log files.
27376 The following example will configure the service with default values.
27377 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
27380 (service tailon-service-type)
27383 The following example customises more of the Tailon configuration,
27384 adding @command{sed} to the list of allowed commands.
27387 (service tailon-service-type
27388 (tailon-configuration
27390 (tailon-configuration-file
27391 (allowed-commands '("tail" "grep" "awk" "sed"))))))
27395 @deftp {Data Type} tailon-configuration
27396 Data type representing the configuration of Tailon.
27397 This type has the following parameters:
27400 @item @code{config-file} (default: @code{(tailon-configuration-file)})
27401 The configuration file to use for Tailon. This can be set to a
27402 @dfn{tailon-configuration-file} record value, or any gexp
27403 (@pxref{G-Expressions}).
27405 For example, to instead use a local file, the @code{local-file} function
27409 (service tailon-service-type
27410 (tailon-configuration
27411 (config-file (local-file "./my-tailon.conf"))))
27414 @item @code{package} (default: @code{tailon})
27415 The tailon package to use.
27420 @deftp {Data Type} tailon-configuration-file
27421 Data type representing the configuration options for Tailon.
27422 This type has the following parameters:
27425 @item @code{files} (default: @code{(list "/var/log")})
27426 List of files to display. The list can include strings for a single file
27427 or directory, or a list, where the first item is the name of a
27428 subsection, and the remaining items are the files or directories in that
27431 @item @code{bind} (default: @code{"localhost:8080"})
27432 Address and port to which Tailon should bind on.
27434 @item @code{relative-root} (default: @code{#f})
27435 URL path to use for Tailon, set to @code{#f} to not use a path.
27437 @item @code{allow-transfers?} (default: @code{#t})
27438 Allow downloading the log files in the web interface.
27440 @item @code{follow-names?} (default: @code{#t})
27441 Allow tailing of not-yet existent files.
27443 @item @code{tail-lines} (default: @code{200})
27444 Number of lines to read initially from each file.
27446 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
27447 Commands to allow running. By default, @code{sed} is disabled.
27449 @item @code{debug?} (default: @code{#f})
27450 Set @code{debug?} to @code{#t} to show debug messages.
27452 @item @code{wrap-lines} (default: @code{#t})
27453 Initial line wrapping state in the web interface. Set to @code{#t} to
27454 initially wrap lines (the default), or to @code{#f} to initially not
27457 @item @code{http-auth} (default: @code{#f})
27458 HTTP authentication type to use. Set to @code{#f} to disable
27459 authentication (the default). Supported values are @code{"digest"} or
27462 @item @code{users} (default: @code{#f})
27463 If HTTP authentication is enabled (see @code{http-auth}), access will be
27464 restricted to the credentials provided here. To configure users, use a
27465 list of pairs, where the first element of the pair is the username, and
27466 the 2nd element of the pair is the password.
27469 (tailon-configuration-file
27470 (http-auth "basic")
27471 (users '(("user1" . "password1")
27472 ("user2" . "password2"))))
27479 @subsubheading Darkstat Service
27481 Darkstat is a packet sniffer that captures network traffic, calculates
27482 statistics about usage, and serves reports over HTTP.
27484 @defvar {Scheme Variable} darkstat-service-type
27485 This is the service type for the
27486 @uref{https://unix4lyfe.org/darkstat/, darkstat}
27487 service, its value must be a @code{darkstat-configuration} record as in
27491 (service darkstat-service-type
27492 (darkstat-configuration
27493 (interface "eno1")))
27497 @deftp {Data Type} darkstat-configuration
27498 Data type representing the configuration of @command{darkstat}.
27501 @item @code{package} (default: @code{darkstat})
27502 The darkstat package to use.
27504 @item @code{interface}
27505 Capture traffic on the specified network interface.
27507 @item @code{port} (default: @code{"667"})
27508 Bind the web interface to the specified port.
27510 @item @code{bind-address} (default: @code{"127.0.0.1"})
27511 Bind the web interface to the specified address.
27513 @item @code{base} (default: @code{"/"})
27514 Specify the path of the base URL@. This can be useful if
27515 @command{darkstat} is accessed via a reverse proxy.
27520 @anchor{prometheus-node-exporter}
27521 @subsubheading Prometheus Node Exporter Service
27522 @cindex prometheus-node-exporter
27524 The Prometheus ``node exporter'' makes hardware and operating system statistics
27525 provided by the Linux kernel available for the Prometheus monitoring system.
27526 This service should be deployed on all physical nodes and virtual machines,
27527 where monitoring these statistics is desirable.
27529 @defvar {Scheme variable} prometheus-node-exporter-service-type
27530 This is the service type for the
27531 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
27532 service, its value must be a @code{prometheus-node-exporter-configuration}.
27535 (service prometheus-node-exporter-service-type)
27539 @deftp {Data Type} prometheus-node-exporter-configuration
27540 Data type representing the configuration of @command{node_exporter}.
27543 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
27544 The prometheus-node-exporter package to use.
27546 @item @code{web-listen-address} (default: @code{":9100"})
27547 Bind the web interface to the specified address.
27549 @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
27550 This directory can be used to export metrics specific to this machine.
27551 Files containing metrics in the text format, with the filename ending in
27552 @code{.prom} should be placed in this directory.
27554 @item @code{extra-options} (default: @code{'()})
27555 Extra options to pass to the Prometheus node exporter.
27560 @subsubheading Zabbix server
27561 @cindex zabbix zabbix-server
27562 Zabbix is a high performance monitoring system that can collect data from a
27563 variety of sources and provide the results in a web-based interface. Alerting
27564 and reporting is built-in, as well as @dfn{templates} for common operating
27565 system metrics such as network utilization, CPU load, and disk space consumption.
27567 This service provides the central Zabbix monitoring service; you also need
27568 @ref{zabbix-front-end,@code{zabbix-front-end-service-type}} to configure Zabbix
27569 and display results, and optionally @ref{zabbix-agent,
27570 @code{zabbix-agent-service-type}} on machines that should be monitored (other
27571 data sources are supported, such as @ref{prometheus-node-exporter,
27572 Prometheus Node Exporter}).
27574 @defvar {Scheme variable} zabbix-server-service-type
27575 This is the service type for the Zabbix server service. Its value must be a
27576 @code{zabbix-server-configuration} record, shown below.
27579 @c %start of fragment
27581 @deftp {Data Type} zabbix-server-configuration
27582 Available @code{zabbix-server-configuration} fields are:
27585 @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
27586 The zabbix-server package.
27588 @item @code{user} (default: @code{"zabbix"}) (type: string)
27589 User who will run the Zabbix server.
27591 @item @code{group} (default: @code{"zabbix"}) (type: group)
27592 Group who will run the Zabbix server.
27594 @item @code{db-host} (default: @code{"127.0.0.1"}) (type: string)
27595 Database host name.
27597 @item @code{db-name} (default: @code{"zabbix"}) (type: string)
27600 @item @code{db-user} (default: @code{"zabbix"}) (type: string)
27603 @item @code{db-password} (default: @code{""}) (type: string)
27604 Database password. Please, use @code{include-files} with
27605 @code{DBPassword=SECRET} inside a specified file instead.
27607 @item @code{db-port} (default: @code{5432}) (type: number)
27610 @item @code{log-type} (default: @code{""}) (type: string)
27611 Specifies where log messages are written to:
27615 @item @code{system} - syslog.
27617 @item @code{file} - file specified with @code{log-file} parameter.
27619 @item @code{console} - standard output.
27623 @item @code{log-file} (default: @code{"/var/log/zabbix/server.log"}) (type: string)
27624 Log file name for @code{log-type} @code{file} parameter.
27626 @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_server.pid"}) (type: string)
27629 @item @code{ssl-ca-location} (default: @code{"/etc/ssl/certs/ca-certificates.crt"}) (type: string)
27630 The location of certificate authority (CA) files for SSL server
27631 certificate verification.
27633 @item @code{ssl-cert-location} (default: @code{"/etc/ssl/certs"}) (type: string)
27634 Location of SSL client certificates.
27636 @item @code{extra-options} (default: @code{""}) (type: extra-options)
27637 Extra options will be appended to Zabbix server configuration file.
27639 @item @code{include-files} (default: @code{()}) (type: include-files)
27640 You may include individual files or all files in a directory in the
27641 configuration file.
27648 @c %end of fragment
27650 @anchor{zabbix-agent}
27651 @subsubheading Zabbix agent
27652 @cindex zabbix zabbix-agent
27654 The Zabbix agent gathers information about the running system for the Zabbix
27655 monitoring server. It has a variety of built-in checks, and can be extended
27657 @uref{https://www.zabbix.com/documentation/current/en/manual/config/items/userparameters,
27658 @dfn{user parameters}}.
27660 @defvar {Scheme variable} zabbix-agent-service-type
27661 This is the service type for the Zabbix agent service. Its value must be a
27662 @code{zabbix-agent-configuration} record, shown below.
27665 @c %start of fragment
27667 @deftp {Data Type} zabbix-agent-configuration
27668 Available @code{zabbix-agent-configuration} fields are:
27671 @item @code{zabbix-agent} (default: @code{zabbix-agentd}) (type: file-like)
27672 The zabbix-agent package.
27674 @item @code{user} (default: @code{"zabbix"}) (type: string)
27675 User who will run the Zabbix agent.
27677 @item @code{group} (default: @code{"zabbix"}) (type: group)
27678 Group who will run the Zabbix agent.
27680 @item @code{hostname} (default: @code{""}) (type: string)
27681 Unique, case sensitive hostname which is required for active checks and
27682 must match hostname as configured on the server.
27684 @item @code{log-type} (default: @code{""}) (type: string)
27685 Specifies where log messages are written to:
27689 @code{system} - syslog.
27691 @item @code{file} - file specified with
27692 @code{log-file} parameter.
27694 @item @code{console} - standard output.
27698 @item @code{log-file} (default: @code{"/var/log/zabbix/agent.log"}) (type: string)
27699 Log file name for @code{log-type} @code{file} parameter.
27701 @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_agent.pid"}) (type: string)
27704 @item @code{server} (default: @code{("127.0.0.1")}) (type: list)
27705 List of IP addresses, optionally in CIDR notation, or hostnames of
27706 Zabbix servers and Zabbix proxies. Incoming connections will be
27707 accepted only from the hosts listed here.
27709 @item @code{server-active} (default: @code{("127.0.0.1")}) (type: list)
27710 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
27711 proxies for active checks. If port is not specified, default port is
27712 used. If this parameter is not specified, active checks are disabled.
27714 @item @code{extra-options} (default: @code{""}) (type: extra-options)
27715 Extra options will be appended to Zabbix server configuration file.
27717 @item @code{include-files} (default: @code{()}) (type: include-files)
27718 You may include individual files or all files in a directory in the
27719 configuration file.
27726 @c %end of fragment
27728 @anchor{zabbix-front-end}
27729 @subsubheading Zabbix front-end
27730 @cindex zabbix zabbix-front-end
27732 The Zabbix front-end provides a web interface to Zabbix. It does not need
27733 to run on the same machine as the Zabbix server. This service works by
27734 extending the @ref{PHP-FPM} and @ref{NGINX} services with the configuration
27735 necessary for loading the Zabbix user interface.
27737 @defvar {Scheme variable} zabbix-front-end-service-type
27738 This is the service type for the Zabbix web frontend. Its value must be a
27739 @code{zabbix-front-end-configuration} record, shown below.
27742 @c %start of fragment
27744 @deftp {Data Type} zabbix-front-end-configuration
27745 Available @code{zabbix-front-end-configuration} fields are:
27748 @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
27749 The Zabbix server package to use.
27751 @item @code{nginx} (default: @code{()}) (type: list)
27752 List of @ref{nginx-server-configuration,@code{nginx-server-configuration}}
27753 blocks for the Zabbix front-end. When empty, a default that listens on
27756 @item @code{db-host} (default: @code{"localhost"}) (type: string)
27757 Database host name.
27759 @item @code{db-port} (default: @code{5432}) (type: number)
27762 @item @code{db-name} (default: @code{"zabbix"}) (type: string)
27765 @item @code{db-user} (default: @code{"zabbix"}) (type: string)
27768 @item @code{db-password} (default: @code{""}) (type: string)
27769 Database password. Please, use @code{db-secret-file} instead.
27771 @item @code{db-secret-file} (default: @code{""}) (type: string)
27772 Secret file which will be appended to @file{zabbix.conf.php} file. This
27773 file contains credentials for use by Zabbix front-end. You are expected
27774 to create it manually.
27776 @item @code{zabbix-host} (default: @code{"localhost"}) (type: string)
27777 Zabbix server hostname.
27779 @item @code{zabbix-port} (default: @code{10051}) (type: number)
27780 Zabbix server port.
27787 @c %end of fragment
27789 @node Kerberos Services
27790 @subsection Kerberos Services
27793 The @code{(gnu services kerberos)} module provides services relating to
27794 the authentication protocol @dfn{Kerberos}.
27796 @subsubheading Krb5 Service
27798 Programs using a Kerberos client library normally
27799 expect a configuration file in @file{/etc/krb5.conf}.
27800 This service generates such a file from a definition provided in the
27801 operating system declaration.
27802 It does not cause any daemon to be started.
27804 No ``keytab'' files are provided by this service---you must explicitly create them.
27805 This service is known to work with the MIT client library, @code{mit-krb5}.
27806 Other implementations have not been tested.
27808 @defvr {Scheme Variable} krb5-service-type
27809 A service type for Kerberos 5 clients.
27813 Here is an example of its use:
27815 (service krb5-service-type
27816 (krb5-configuration
27817 (default-realm "EXAMPLE.COM")
27818 (allow-weak-crypto? #t)
27821 (name "EXAMPLE.COM")
27822 (admin-server "groucho.example.com")
27823 (kdc "karl.example.com"))
27826 (admin-server "kerb-admin.argrx.edu")
27827 (kdc "keys.argrx.edu"))))))
27831 This example provides a Kerberos@tie{}5 client configuration which:
27833 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
27834 of which have distinct administration servers and key distribution centers;
27835 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
27836 specified by clients;
27837 @item Accepts services which only support encryption types known to be weak.
27840 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
27841 Only the most commonly used ones are described here.
27842 For a full list, and more detailed explanation of each, see the MIT
27843 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
27847 @deftp {Data Type} krb5-realm
27848 @cindex realm, kerberos
27851 This field is a string identifying the name of the realm.
27852 A common convention is to use the fully qualified DNS name of your organization,
27853 converted to upper case.
27855 @item @code{admin-server}
27856 This field is a string identifying the host where the administration server is
27860 This field is a string identifying the key distribution center
27865 @deftp {Data Type} krb5-configuration
27868 @item @code{allow-weak-crypto?} (default: @code{#f})
27869 If this flag is @code{#t} then services which only offer encryption algorithms
27870 known to be weak will be accepted.
27872 @item @code{default-realm} (default: @code{#f})
27873 This field should be a string identifying the default Kerberos
27874 realm for the client.
27875 You should set this field to the name of your Kerberos realm.
27876 If this value is @code{#f}
27877 then a realm must be specified with every Kerberos principal when invoking programs
27878 such as @command{kinit}.
27880 @item @code{realms}
27881 This should be a non-empty list of @code{krb5-realm} objects, which clients may
27883 Normally, one of them will have a @code{name} field matching the @code{default-realm}
27889 @subsubheading PAM krb5 Service
27892 The @code{pam-krb5} service allows for login authentication and password
27893 management via Kerberos.
27894 You will need this service if you want PAM enabled applications to authenticate
27895 users using Kerberos.
27897 @defvr {Scheme Variable} pam-krb5-service-type
27898 A service type for the Kerberos 5 PAM module.
27901 @deftp {Data Type} pam-krb5-configuration
27902 Data type representing the configuration of the Kerberos 5 PAM module.
27903 This type has the following parameters:
27905 @item @code{pam-krb5} (default: @code{pam-krb5})
27906 The pam-krb5 package to use.
27908 @item @code{minimum-uid} (default: @code{1000})
27909 The smallest user ID for which Kerberos authentications should be attempted.
27910 Local accounts with lower values will silently fail to authenticate.
27915 @node LDAP Services
27916 @subsection LDAP Services
27918 @cindex nslcd, LDAP service
27920 The @code{(gnu services authentication)} module provides the
27921 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
27922 server. In addition to configuring the service itself, you may want to add
27923 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
27924 Switch} for detailed information.
27926 Here is a simple operating system declaration with a default configuration of
27927 the @code{nslcd-service-type} and a Name Service Switch configuration that
27928 consults the @code{ldap} name service last:
27931 (use-service-modules authentication)
27932 (use-modules (gnu system nss))
27938 (service nslcd-service-type)
27939 (service dhcp-client-service-type)
27941 (name-service-switch
27942 (let ((services (list (name-service (name "db"))
27943 (name-service (name "files"))
27944 (name-service (name "ldap")))))
27945 (name-service-switch
27946 (inherit %mdns-host-lookup-nss)
27947 (password services)
27950 (netgroup services)
27951 (gshadow services)))))
27954 @c %start of generated documentation for nslcd-configuration
27956 Available @code{nslcd-configuration} fields are:
27958 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
27959 The @code{nss-pam-ldapd} package to use.
27963 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
27964 The number of threads to start that can handle requests and perform LDAP
27965 queries. Each thread opens a separate connection to the LDAP server.
27966 The default is to start 5 threads.
27968 Defaults to @samp{disabled}.
27972 @deftypevr {@code{nslcd-configuration} parameter} string uid
27973 This specifies the user id with which the daemon should be run.
27975 Defaults to @samp{"nslcd"}.
27979 @deftypevr {@code{nslcd-configuration} parameter} string gid
27980 This specifies the group id with which the daemon should be run.
27982 Defaults to @samp{"nslcd"}.
27986 @deftypevr {@code{nslcd-configuration} parameter} log-option log
27987 This option controls the way logging is done via a list containing
27988 SCHEME and LEVEL@. The SCHEME argument may either be the symbols
27989 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
27990 argument is optional and specifies the log level. The log level may be
27991 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
27992 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
27993 specified log level or higher are logged.
27995 Defaults to @samp{("/var/log/nslcd" info)}.
27999 @deftypevr {@code{nslcd-configuration} parameter} list uri
28000 The list of LDAP server URIs. Normally, only the first server will be
28001 used with the following servers as fall-back.
28003 Defaults to @samp{("ldap://localhost:389/")}.
28007 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
28008 The version of the LDAP protocol to use. The default is to use the
28009 maximum version supported by the LDAP library.
28011 Defaults to @samp{disabled}.
28015 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
28016 Specifies the distinguished name with which to bind to the directory
28017 server for lookups. The default is to bind anonymously.
28019 Defaults to @samp{disabled}.
28023 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
28024 Specifies the credentials with which to bind. This option is only
28025 applicable when used with binddn.
28027 Defaults to @samp{disabled}.
28031 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
28032 Specifies the distinguished name to use when the root user tries to
28033 modify a user's password using the PAM module.
28035 Defaults to @samp{disabled}.
28039 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
28040 Specifies the credentials with which to bind if the root user tries to
28041 change a user's password. This option is only applicable when used with
28044 Defaults to @samp{disabled}.
28048 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
28049 Specifies the SASL mechanism to be used when performing SASL
28052 Defaults to @samp{disabled}.
28056 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
28057 Specifies the SASL realm to be used when performing SASL authentication.
28059 Defaults to @samp{disabled}.
28063 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
28064 Specifies the authentication identity to be used when performing SASL
28067 Defaults to @samp{disabled}.
28071 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
28072 Specifies the authorization identity to be used when performing SASL
28075 Defaults to @samp{disabled}.
28079 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
28080 Determines whether the LDAP server host name should be canonicalised. If
28081 this is enabled the LDAP library will do a reverse host name lookup. By
28082 default, it is left up to the LDAP library whether this check is
28085 Defaults to @samp{disabled}.
28089 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
28090 Set the name for the GSS-API Kerberos credentials cache.
28092 Defaults to @samp{disabled}.
28096 @deftypevr {@code{nslcd-configuration} parameter} string base
28097 The directory search base.
28099 Defaults to @samp{"dc=example,dc=com"}.
28103 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
28104 Specifies the search scope (subtree, onelevel, base or children). The
28105 default scope is subtree; base scope is almost never useful for name
28106 service lookups; children scope is not supported on all servers.
28108 Defaults to @samp{(subtree)}.
28112 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
28113 Specifies the policy for dereferencing aliases. The default policy is
28114 to never dereference aliases.
28116 Defaults to @samp{disabled}.
28120 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
28121 Specifies whether automatic referral chasing should be enabled. The
28122 default behaviour is to chase referrals.
28124 Defaults to @samp{disabled}.
28128 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
28129 This option allows for custom attributes to be looked up instead of the
28130 default RFC 2307 attributes. It is a list of maps, each consisting of
28131 the name of a map, the RFC 2307 attribute to match and the query
28132 expression for the attribute as it is available in the directory.
28134 Defaults to @samp{()}.
28138 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
28139 A list of filters consisting of the name of a map to which the filter
28140 applies and an LDAP search filter expression.
28142 Defaults to @samp{()}.
28146 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
28147 Specifies the time limit in seconds to use when connecting to the
28148 directory server. The default value is 10 seconds.
28150 Defaults to @samp{disabled}.
28154 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
28155 Specifies the time limit (in seconds) to wait for a response from the
28156 LDAP server. A value of zero, which is the default, is to wait
28157 indefinitely for searches to be completed.
28159 Defaults to @samp{disabled}.
28163 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
28164 Specifies the period if inactivity (in seconds) after which the con‐
28165 nection to the LDAP server will be closed. The default is not to time
28168 Defaults to @samp{disabled}.
28172 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
28173 Specifies the number of seconds to sleep when connecting to all LDAP
28174 servers fails. By default one second is waited between the first
28175 failure and the first retry.
28177 Defaults to @samp{disabled}.
28181 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
28182 Specifies the time after which the LDAP server is considered to be
28183 permanently unavailable. Once this time is reached retries will be done
28184 only once per this time period. The default value is 10 seconds.
28186 Defaults to @samp{disabled}.
28190 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
28191 Specifies whether to use SSL/TLS or not (the default is not to). If
28192 'start-tls is specified then StartTLS is used rather than raw LDAP over
28195 Defaults to @samp{disabled}.
28199 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
28200 Specifies what checks to perform on a server-supplied certificate. The
28201 meaning of the values is described in the ldap.conf(5) manual page.
28203 Defaults to @samp{disabled}.
28207 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
28208 Specifies the directory containing X.509 certificates for peer authen‐
28209 tication. This parameter is ignored when using GnuTLS.
28211 Defaults to @samp{disabled}.
28215 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
28216 Specifies the path to the X.509 certificate for peer authentication.
28218 Defaults to @samp{disabled}.
28222 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
28223 Specifies the path to an entropy source. This parameter is ignored when
28226 Defaults to @samp{disabled}.
28230 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
28231 Specifies the ciphers to use for TLS as a string.
28233 Defaults to @samp{disabled}.
28237 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
28238 Specifies the path to the file containing the local certificate for
28239 client TLS authentication.
28241 Defaults to @samp{disabled}.
28245 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
28246 Specifies the path to the file containing the private key for client TLS
28249 Defaults to @samp{disabled}.
28253 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
28254 Set this to a number greater than 0 to request paged results from the
28255 LDAP server in accordance with RFC2696. The default (0) is to not
28256 request paged results.
28258 Defaults to @samp{disabled}.
28262 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
28263 This option prevents group membership lookups through LDAP for the
28264 specified users. Alternatively, the value 'all-local may be used. With
28265 that value nslcd builds a full list of non-LDAP users on startup.
28267 Defaults to @samp{disabled}.
28271 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
28272 This option ensures that LDAP users with a numeric user id lower than
28273 the specified value are ignored.
28275 Defaults to @samp{disabled}.
28279 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
28280 This option specifies an offset that is added to all LDAP numeric user
28281 ids. This can be used to avoid user id collisions with local users.
28283 Defaults to @samp{disabled}.
28287 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
28288 This option specifies an offset that is added to all LDAP numeric group
28289 ids. This can be used to avoid user id collisions with local groups.
28291 Defaults to @samp{disabled}.
28295 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
28296 If this option is set, the member attribute of a group may point to
28297 another group. Members of nested groups are also returned in the higher
28298 level group and parent groups are returned when finding groups for a
28299 specific user. The default is not to perform extra searches for nested
28302 Defaults to @samp{disabled}.
28306 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
28307 If this option is set, the group member list is not retrieved when
28308 looking up groups. Lookups for finding which groups a user belongs to
28309 will remain functional so the user will likely still get the correct
28310 groups assigned on login.
28312 Defaults to @samp{disabled}.
28316 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
28317 If this option is set, functions which cause all user/group entries to
28318 be loaded from the directory will not succeed in doing so. This can
28319 dramatically reduce LDAP server load in situations where there are a
28320 great number of users and/or groups. This option is not recommended for
28321 most configurations.
28323 Defaults to @samp{disabled}.
28327 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
28328 This option can be used to specify how user and group names are verified
28329 within the system. This pattern is used to check all user and group
28330 names that are requested and returned from LDAP.
28332 Defaults to @samp{disabled}.
28336 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
28337 This specifies whether or not to perform searches using case-insensitive
28338 matching. Enabling this could open up the system to authorization
28339 bypass vulnerabilities and introduce nscd cache poisoning
28340 vulnerabilities which allow denial of service.
28342 Defaults to @samp{disabled}.
28346 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
28347 This option specifies whether password policy controls are requested and
28348 handled from the LDAP server when performing user authentication.
28350 Defaults to @samp{disabled}.
28354 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
28355 By default nslcd performs an LDAP search with the user's credentials
28356 after BIND (authentication) to ensure that the BIND operation was
28357 successful. The default search is a simple check to see if the user's
28358 DN exists. A search filter can be specified that will be used instead.
28359 It should return at least one entry.
28361 Defaults to @samp{disabled}.
28365 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
28366 This option allows flexible fine tuning of the authorisation check that
28367 should be performed. The search filter specified is executed and if any
28368 entries match, access is granted, otherwise access is denied.
28370 Defaults to @samp{disabled}.
28374 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
28375 If this option is set password modification using pam_ldap will be
28376 denied and the specified message will be presented to the user instead.
28377 The message can be used to direct the user to an alternative means of
28378 changing their password.
28380 Defaults to @samp{disabled}.
28384 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
28385 List of pam service names for which LDAP authentication should suffice.
28387 Defaults to @samp{()}.
28391 @c %end of generated documentation for nslcd-configuration
28395 @subsection Web Services
28400 The @code{(gnu services web)} module provides the Apache HTTP Server,
28401 the nginx web server, and also a fastcgi wrapper daemon.
28403 @subsubheading Apache HTTP Server
28405 @deffn {Scheme Variable} httpd-service-type
28406 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
28407 (@dfn{httpd}). The value for this service type is a
28408 @code{httpd-configuration} record.
28410 A simple example configuration is given below.
28413 (service httpd-service-type
28414 (httpd-configuration
28417 (server-name "www.example.com")
28418 (document-root "/srv/http/www.example.com")))))
28421 Other services can also extend the @code{httpd-service-type} to add to
28425 (simple-service 'www.example.com-server httpd-service-type
28429 (list (string-join '("ServerName www.example.com"
28430 "DocumentRoot /srv/http/www.example.com")
28435 The details for the @code{httpd-configuration}, @code{httpd-module},
28436 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
28439 @deffn {Data Type} httpd-configuration
28440 This data type represents the configuration for the httpd service.
28443 @item @code{package} (default: @code{httpd})
28444 The httpd package to use.
28446 @item @code{pid-file} (default: @code{"/var/run/httpd"})
28447 The pid file used by the shepherd-service.
28449 @item @code{config} (default: @code{(httpd-config-file)})
28450 The configuration file to use with the httpd service. The default value
28451 is a @code{httpd-config-file} record, but this can also be a different
28452 G-expression that generates a file, for example a @code{plain-file}. A
28453 file outside of the store can also be specified through a string.
28458 @deffn {Data Type} httpd-module
28459 This data type represents a module for the httpd service.
28463 The name of the module.
28466 The file for the module. This can be relative to the httpd package being
28467 used, the absolute location of a file, or a G-expression for a file
28468 within the store, for example @code{(file-append mod-wsgi
28469 "/modules/mod_wsgi.so")}.
28474 @defvr {Scheme Variable} %default-httpd-modules
28475 A default list of @code{httpd-module} objects.
28478 @deffn {Data Type} httpd-config-file
28479 This data type represents a configuration file for the httpd service.
28482 @item @code{modules} (default: @code{%default-httpd-modules})
28483 The modules to load. Additional modules can be added here, or loaded by
28484 additional configuration.
28486 For example, in order to handle requests for PHP files, you can use Apache’s
28487 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
28490 (service httpd-service-type
28491 (httpd-configuration
28496 (name "proxy_module")
28497 (file "modules/mod_proxy.so"))
28499 (name "proxy_fcgi_module")
28500 (file "modules/mod_proxy_fcgi.so"))
28501 %default-httpd-modules))
28502 (extra-config (list "\
28503 <FilesMatch \\.php$>
28504 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
28505 </FilesMatch>"))))))
28506 (service php-fpm-service-type
28507 (php-fpm-configuration
28508 (socket "/var/run/php-fpm.sock")
28509 (socket-group "httpd")))
28512 @item @code{server-root} (default: @code{httpd})
28513 The @code{ServerRoot} in the configuration file, defaults to the httpd
28514 package. Directives including @code{Include} and @code{LoadModule} are
28515 taken as relative to the server root.
28517 @item @code{server-name} (default: @code{#f})
28518 The @code{ServerName} in the configuration file, used to specify the
28519 request scheme, hostname and port that the server uses to identify
28522 This doesn't need to be set in the server config, and can be specified
28523 in virtual hosts. The default is @code{#f} to not specify a
28526 @item @code{document-root} (default: @code{"/srv/http"})
28527 The @code{DocumentRoot} from which files will be served.
28529 @item @code{listen} (default: @code{'("80")})
28530 The list of values for the @code{Listen} directives in the config
28531 file. The value should be a list of strings, when each string can
28532 specify the port number to listen on, and optionally the IP address and
28535 @item @code{pid-file} (default: @code{"/var/run/httpd"})
28536 The @code{PidFile} to use. This should match the @code{pid-file} set in
28537 the @code{httpd-configuration} so that the Shepherd service is
28538 configured correctly.
28540 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
28541 The @code{ErrorLog} to which the server will log errors.
28543 @item @code{user} (default: @code{"httpd"})
28544 The @code{User} which the server will answer requests as.
28546 @item @code{group} (default: @code{"httpd"})
28547 The @code{Group} which the server will answer requests as.
28549 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
28550 A flat list of strings and G-expressions which will be added to the end
28551 of the configuration file.
28553 Any values which the service is extended with will be appended to this
28559 @deffn {Data Type} httpd-virtualhost
28560 This data type represents a virtualhost configuration block for the httpd service.
28562 These should be added to the extra-config for the httpd-service.
28565 (simple-service 'www.example.com-server httpd-service-type
28569 (list (string-join '("ServerName www.example.com"
28570 "DocumentRoot /srv/http/www.example.com")
28575 @item @code{addresses-and-ports}
28576 The addresses and ports for the @code{VirtualHost} directive.
28578 @item @code{contents}
28579 The contents of the @code{VirtualHost} directive, this should be a list
28580 of strings and G-expressions.
28586 @subsubheading NGINX
28588 @deffn {Scheme Variable} nginx-service-type
28589 Service type for the @uref{https://nginx.org/,NGinx} web server. The
28590 value for this service type is a @code{<nginx-configuration>} record.
28592 A simple example configuration is given below.
28595 (service nginx-service-type
28596 (nginx-configuration
28598 (list (nginx-server-configuration
28599 (server-name '("www.example.com"))
28600 (root "/srv/http/www.example.com"))))))
28603 In addition to adding server blocks to the service configuration
28604 directly, this service can be extended by other services to add server
28605 blocks, as in this example:
28608 (simple-service 'my-extra-server nginx-service-type
28609 (list (nginx-server-configuration
28610 (root "/srv/http/extra-website")
28611 (try-files (list "$uri" "$uri/index.html")))))
28615 At startup, @command{nginx} has not yet read its configuration file, so
28616 it uses a default file to log error messages. If it fails to load its
28617 configuration file, that is where error messages are logged. After the
28618 configuration file is loaded, the default error log file changes as per
28619 configuration. In our case, startup error messages can be found in
28620 @file{/var/run/nginx/logs/error.log}, and after configuration in
28621 @file{/var/log/nginx/error.log}. The second location can be changed
28622 with the @var{log-directory} configuration option.
28624 @deffn {Data Type} nginx-configuration
28625 This data type represents the configuration for NGinx. Some
28626 configuration can be done through this and the other provided record
28627 types, or alternatively, a config file can be provided.
28630 @item @code{nginx} (default: @code{nginx})
28631 The nginx package to use.
28633 @item @code{log-directory} (default: @code{"/var/log/nginx"})
28634 The directory to which NGinx will write log files.
28636 @item @code{run-directory} (default: @code{"/var/run/nginx"})
28637 The directory in which NGinx will create a pid file, and write temporary
28640 @item @code{server-blocks} (default: @code{'()})
28641 A list of @dfn{server blocks} to create in the generated configuration
28642 file, the elements should be of type
28643 @code{<nginx-server-configuration>}.
28645 The following example would setup NGinx to serve @code{www.example.com}
28646 from the @code{/srv/http/www.example.com} directory, without using
28649 (service nginx-service-type
28650 (nginx-configuration
28652 (list (nginx-server-configuration
28653 (server-name '("www.example.com"))
28654 (root "/srv/http/www.example.com"))))))
28657 @item @code{upstream-blocks} (default: @code{'()})
28658 A list of @dfn{upstream blocks} to create in the generated configuration
28659 file, the elements should be of type
28660 @code{<nginx-upstream-configuration>}.
28662 Configuring upstreams through the @code{upstream-blocks} can be useful
28663 when combined with @code{locations} in the
28664 @code{<nginx-server-configuration>} records. The following example
28665 creates a server configuration with one location configuration, that
28666 will proxy requests to a upstream configuration, which will handle
28667 requests with two servers.
28672 (nginx-configuration
28674 (list (nginx-server-configuration
28675 (server-name '("www.example.com"))
28676 (root "/srv/http/www.example.com")
28679 (nginx-location-configuration
28681 (body '("proxy_pass http://server-proxy;"))))))))
28683 (list (nginx-upstream-configuration
28684 (name "server-proxy")
28685 (servers (list "server1.example.com"
28686 "server2.example.com")))))))
28689 @item @code{file} (default: @code{#f})
28690 If a configuration @var{file} is provided, this will be used, rather than
28691 generating a configuration file from the provided @code{log-directory},
28692 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
28693 proper operation, these arguments should match what is in @var{file} to ensure
28694 that the directories are created when the service is activated.
28696 This can be useful if you have an existing configuration file, or it's
28697 not possible to do what is required through the other parts of the
28698 nginx-configuration record.
28700 @item @code{server-names-hash-bucket-size} (default: @code{#f})
28701 Bucket size for the server names hash tables, defaults to @code{#f} to
28702 use the size of the processors cache line.
28704 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
28705 Maximum bucket size for the server names hash tables.
28707 @item @code{modules} (default: @code{'()})
28708 List of nginx dynamic modules to load. This should be a list of file
28709 names of loadable modules, as in this example:
28714 (file-append nginx-accept-language-module "\
28715 /etc/nginx/modules/ngx_http_accept_language_module.so")
28716 (file-append nginx-lua-module "\
28717 /etc/nginx/modules/ngx_http_lua_module.so")))
28720 @item @code{lua-package-path} (default: @code{'()})
28721 List of nginx lua packages to load. This should be a list of package
28722 names of loadable lua modules, as in this example:
28725 (lua-package-path (list lua-resty-core
28732 @item @code{lua-package-cpath} (default: @code{'()})
28733 List of nginx lua C packages to load. This should be a list of package
28734 names of loadable lua C modules, as in this example:
28737 (lua-package-cpath (list lua-resty-signal))
28740 @item @code{global-directives} (default: @code{'((events . ()))})
28741 Association list of global directives for the top level of the nginx
28742 configuration. Values may themselves be association lists.
28746 `((worker_processes . 16)
28748 (events . ((worker_connections . 1024)))))
28751 @item @code{extra-content} (default: @code{""})
28752 Extra content for the @code{http} block. Should be string or a string
28753 valued G-expression.
28758 @anchor{nginx-server-configuration}
28759 @deftp {Data Type} nginx-server-configuration
28760 Data type representing the configuration of an nginx server block.
28761 This type has the following parameters:
28764 @item @code{listen} (default: @code{'("80" "443 ssl")})
28765 Each @code{listen} directive sets the address and port for IP, or the
28766 path for a UNIX-domain socket on which the server will accept requests.
28767 Both address and port, or only address or only port can be specified.
28768 An address may also be a hostname, for example:
28771 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
28774 @item @code{server-name} (default: @code{(list 'default)})
28775 A list of server names this server represents. @code{'default} represents the
28776 default server for connections matching no other server.
28778 @item @code{root} (default: @code{"/srv/http"})
28779 Root of the website nginx will serve.
28781 @item @code{locations} (default: @code{'()})
28782 A list of @dfn{nginx-location-configuration} or
28783 @dfn{nginx-named-location-configuration} records to use within this
28786 @item @code{index} (default: @code{(list "index.html")})
28787 Index files to look for when clients ask for a directory. If it cannot be found,
28788 Nginx will send the list of files in the directory.
28790 @item @code{try-files} (default: @code{'()})
28791 A list of files whose existence is checked in the specified order.
28792 @code{nginx} will use the first file it finds to process the request.
28794 @item @code{ssl-certificate} (default: @code{#f})
28795 Where to find the certificate for secure connections. Set it to @code{#f} if
28796 you don't have a certificate or you don't want to use HTTPS.
28798 @item @code{ssl-certificate-key} (default: @code{#f})
28799 Where to find the private key for secure connections. Set it to @code{#f} if
28800 you don't have a key or you don't want to use HTTPS.
28802 @item @code{server-tokens?} (default: @code{#f})
28803 Whether the server should add its configuration to response.
28805 @item @code{raw-content} (default: @code{'()})
28806 A list of raw lines added to the server block.
28811 @deftp {Data Type} nginx-upstream-configuration
28812 Data type representing the configuration of an nginx @code{upstream}
28813 block. This type has the following parameters:
28817 Name for this group of servers.
28819 @item @code{servers}
28820 Specify the addresses of the servers in the group. The address can be
28821 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
28822 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
28823 prefix @samp{unix:}. For addresses using an IP address or domain name,
28824 the default port is 80, and a different port can be specified
28827 @item @code{extra-content}
28828 A string or list of strings to add to the upstream block.
28833 @deftp {Data Type} nginx-location-configuration
28834 Data type representing the configuration of an nginx @code{location}
28835 block. This type has the following parameters:
28839 URI which this location block matches.
28841 @anchor{nginx-location-configuration body}
28843 Body of the location block, specified as a list of strings. This can contain
28845 configuration directives. For example, to pass requests to a upstream
28846 server group defined using an @code{nginx-upstream-configuration} block,
28847 the following directive would be specified in the body @samp{(list "proxy_pass
28848 http://upstream-name;")}.
28853 @deftp {Data Type} nginx-named-location-configuration
28854 Data type representing the configuration of an nginx named location
28855 block. Named location blocks are used for request redirection, and not
28856 used for regular request processing. This type has the following
28861 Name to identify this location block.
28864 @xref{nginx-location-configuration body}, as the body for named location
28865 blocks can be used in a similar way to the
28866 @code{nginx-location-configuration body}. One restriction is that the
28867 body of a named location block cannot contain location blocks.
28872 @subsubheading Varnish Cache
28874 Varnish is a fast cache server that sits in between web applications
28875 and end users. It proxies requests from clients and caches the
28876 accessed URLs such that multiple requests for the same resource only
28877 creates one request to the back-end.
28879 @defvr {Scheme Variable} varnish-service-type
28880 Service type for the Varnish daemon.
28883 @deftp {Data Type} varnish-configuration
28884 Data type representing the @code{varnish} service configuration.
28885 This type has the following parameters:
28888 @item @code{package} (default: @code{varnish})
28889 The Varnish package to use.
28891 @item @code{name} (default: @code{"default"})
28892 A name for this Varnish instance. Varnish will create a directory in
28893 @file{/var/varnish/} with this name and keep temporary files there. If
28894 the name starts with a forward slash, it is interpreted as an absolute
28897 Pass the @code{-n} argument to other Varnish programs to connect to the
28898 named instance, e.g.@: @command{varnishncsa -n default}.
28900 @item @code{backend} (default: @code{"localhost:8080"})
28901 The backend to use. This option has no effect if @code{vcl} is set.
28903 @item @code{vcl} (default: #f)
28904 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
28905 is @code{#f}, Varnish will proxy @code{backend} using the default
28906 configuration. Otherwise this must be a file-like object with valid
28909 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
28910 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
28911 can do something along these lines:
28914 (define %gnu-mirror
28915 (plain-file "gnu.vcl"
28917 backend gnu @{ .host = \"www.gnu.org\"; @}"))
28921 (services (cons (service varnish-service-type
28922 (varnish-configuration
28924 (vcl %gnu-mirror)))
28928 The configuration of an already running Varnish instance can be inspected
28929 and changed using the @command{varnishadm} program.
28931 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
28932 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
28933 comprehensive documentation on Varnish and its configuration language.
28935 @item @code{listen} (default: @code{'("localhost:80")})
28936 List of addresses Varnish will listen on.
28938 @item @code{storage} (default: @code{'("malloc,128m")})
28939 List of storage backends that will be available in VCL.
28941 @item @code{parameters} (default: @code{'()})
28942 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
28944 @item @code{extra-options} (default: @code{'()})
28945 Additional arguments to pass to the @command{varnishd} process.
28950 @subsubheading Patchwork
28952 Patchwork is a patch tracking system. It can collect patches sent to a
28953 mailing list, and display them in a web interface.
28955 @defvr {Scheme Variable} patchwork-service-type
28956 Service type for Patchwork.
28959 The following example is an example of a minimal service for Patchwork, for
28960 the @code{patchwork.example.com} domain.
28963 (service patchwork-service-type
28964 (patchwork-configuration
28965 (domain "patchwork.example.com")
28967 (patchwork-settings-module
28968 (allowed-hosts (list domain))
28969 (default-from-email "patchwork@@patchwork.example.com")))
28970 (getmail-retriever-config
28971 (getmail-retriever-configuration
28972 (type "SimpleIMAPSSLRetriever")
28973 (server "imap.example.com")
28975 (username "patchwork")
28977 (list (file-append coreutils "/bin/cat")
28978 "/etc/getmail-patchwork-imap-password"))
28980 '((mailboxes . ("Patches"))))))))
28984 There are three records for configuring the Patchwork service. The
28985 @code{<patchwork-configuration>} relates to the configuration for Patchwork
28986 within the HTTPD service.
28988 The @code{settings-module} field within the @code{<patchwork-configuration>}
28989 record can be populated with the @code{<patchwork-settings-module>} record,
28990 which describes a settings module that is generated within the Guix store.
28992 For the @code{database-configuration} field within the
28993 @code{<patchwork-settings-module>}, the
28994 @code{<patchwork-database-configuration>} must be used.
28996 @deftp {Data Type} patchwork-configuration
28997 Data type representing the Patchwork service configuration. This type has the
28998 following parameters:
29001 @item @code{patchwork} (default: @code{patchwork})
29002 The Patchwork package to use.
29004 @item @code{domain}
29005 The domain to use for Patchwork, this is used in the HTTPD service virtual
29008 @item @code{settings-module}
29009 The settings module to use for Patchwork. As a Django application, Patchwork
29010 is configured with a Python module containing the settings. This can either be
29011 an instance of the @code{<patchwork-settings-module>} record, any other record
29012 that represents the settings in the store, or a directory outside of the
29015 @item @code{static-path} (default: @code{"/static/"})
29016 The path under which the HTTPD service should serve the static files.
29018 @item @code{getmail-retriever-config}
29019 The getmail-retriever-configuration record value to use with
29020 Patchwork. Getmail will be configured with this value, the messages will be
29021 delivered to Patchwork.
29026 @deftp {Data Type} patchwork-settings-module
29027 Data type representing a settings module for Patchwork. Some of these
29028 settings relate directly to Patchwork, but others relate to Django, the web
29029 framework used by Patchwork, or the Django Rest Framework library. This type
29030 has the following parameters:
29033 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
29034 The database connection settings used for Patchwork. See the
29035 @code{<patchwork-database-configuration>} record type for more information.
29037 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
29038 Patchwork, as a Django web application uses a secret key for cryptographically
29039 signing values. This file should contain a unique unpredictable value.
29041 If this file does not exist, it will be created and populated with a random
29042 value by the patchwork-setup shepherd service.
29044 This setting relates to Django.
29046 @item @code{allowed-hosts}
29047 A list of valid hosts for this Patchwork service. This should at least include
29048 the domain specified in the @code{<patchwork-configuration>} record.
29050 This is a Django setting.
29052 @item @code{default-from-email}
29053 The email address from which Patchwork should send email by default.
29055 This is a Patchwork setting.
29057 @item @code{static-url} (default: @code{#f})
29058 The URL to use when serving static assets. It can be part of a URL, or a full
29059 URL, but must end in a @code{/}.
29061 If the default value is used, the @code{static-path} value from the
29062 @code{<patchwork-configuration>} record will be used.
29064 This is a Django setting.
29066 @item @code{admins} (default: @code{'()})
29067 Email addresses to send the details of errors that occur. Each value should
29068 be a list containing two elements, the name and then the email address.
29070 This is a Django setting.
29072 @item @code{debug?} (default: @code{#f})
29073 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
29074 messages will be shown.
29076 This is a Django setting.
29078 @item @code{enable-rest-api?} (default: @code{#t})
29079 Whether to enable the Patchwork REST API.
29081 This is a Patchwork setting.
29083 @item @code{enable-xmlrpc?} (default: @code{#t})
29084 Whether to enable the XML RPC API.
29086 This is a Patchwork setting.
29088 @item @code{force-https-links?} (default: @code{#t})
29089 Whether to use HTTPS links on Patchwork pages.
29091 This is a Patchwork setting.
29093 @item @code{extra-settings} (default: @code{""})
29094 Extra code to place at the end of the Patchwork settings module.
29099 @deftp {Data Type} patchwork-database-configuration
29100 Data type representing the database configuration for Patchwork.
29103 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
29104 The database engine to use.
29106 @item @code{name} (default: @code{"patchwork"})
29107 The name of the database to use.
29109 @item @code{user} (default: @code{"httpd"})
29110 The user to connect to the database as.
29112 @item @code{password} (default: @code{""})
29113 The password to use when connecting to the database.
29115 @item @code{host} (default: @code{""})
29116 The host to make the database connection to.
29118 @item @code{port} (default: @code{""})
29119 The port on which to connect to the database.
29124 @subsubheading Mumi
29126 @cindex Mumi, Debbugs Web interface
29127 @cindex Debbugs, Mumi Web interface
29128 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
29129 Web interface to the Debbugs bug tracker, by default for
29130 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
29131 but it also fetches and indexes mail retrieved from Debbugs.
29133 @defvr {Scheme Variable} mumi-service-type
29134 This is the service type for Mumi.
29137 @deftp {Data Type} mumi-configuration
29138 Data type representing the Mumi service configuration. This type has the
29142 @item @code{mumi} (default: @code{mumi})
29143 The Mumi package to use.
29145 @item @code{mailer?} (default: @code{#true})
29146 Whether to enable or disable the mailer component.
29148 @item @code{mumi-configuration-sender}
29149 The email address used as the sender for comments.
29151 @item @code{mumi-configuration-smtp}
29152 A URI to configure the SMTP settings for Mailutils. This could be
29153 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
29154 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
29155 mailutils, GNU@tie{}Mailutils}.
29161 @subsubheading FastCGI
29164 FastCGI is an interface between the front-end and the back-end of a web
29165 service. It is a somewhat legacy facility; new web services should
29166 generally just talk HTTP between the front-end and the back-end.
29167 However there are a number of back-end services such as PHP or the
29168 optimized HTTP Git repository access that use FastCGI, so we have
29169 support for it in Guix.
29171 To use FastCGI, you configure the front-end web server (e.g., nginx) to
29172 dispatch some subset of its requests to the fastcgi backend, which
29173 listens on a local TCP or UNIX socket. There is an intermediary
29174 @code{fcgiwrap} program that sits between the actual backend process and
29175 the web server. The front-end indicates which backend program to run,
29176 passing that information to the @code{fcgiwrap} process.
29178 @defvr {Scheme Variable} fcgiwrap-service-type
29179 A service type for the @code{fcgiwrap} FastCGI proxy.
29182 @deftp {Data Type} fcgiwrap-configuration
29183 Data type representing the configuration of the @code{fcgiwrap} service.
29184 This type has the following parameters:
29186 @item @code{package} (default: @code{fcgiwrap})
29187 The fcgiwrap package to use.
29189 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
29190 The socket on which the @code{fcgiwrap} process should listen, as a
29191 string. Valid @var{socket} values include
29192 @code{unix:@var{/path/to/unix/socket}},
29193 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
29194 @code{tcp6:[@var{ipv6_addr}]:port}.
29196 @item @code{user} (default: @code{fcgiwrap})
29197 @itemx @code{group} (default: @code{fcgiwrap})
29198 The user and group names, as strings, under which to run the
29199 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
29200 the user asks for the specific user or group names @code{fcgiwrap} that
29201 the corresponding user and/or group is present on the system.
29203 It is possible to configure a FastCGI-backed web service to pass HTTP
29204 authentication information from the front-end to the back-end, and to
29205 allow @code{fcgiwrap} to run the back-end process as a corresponding
29206 local user. To enable this capability on the back-end, run
29207 @code{fcgiwrap} as the @code{root} user and group. Note that this
29208 capability also has to be configured on the front-end as well.
29213 @subsubheading PHP-FPM
29215 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
29216 with some additional features useful for sites of any size.
29218 These features include:
29220 @item Adaptive process spawning
29221 @item Basic statistics (similar to Apache's mod_status)
29222 @item Advanced process management with graceful stop/start
29223 @item Ability to start workers with different uid/gid/chroot/environment
29224 and different php.ini (replaces safe_mode)
29225 @item Stdout & stderr logging
29226 @item Emergency restart in case of accidental opcode cache destruction
29227 @item Accelerated upload support
29228 @item Support for a "slowlog"
29229 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
29230 a special function to finish request & flush all data while continuing to do
29231 something time-consuming (video converting, stats processing, etc.)
29233 ...@: and much more.
29235 @defvr {Scheme Variable} php-fpm-service-type
29236 A Service type for @code{php-fpm}.
29239 @deftp {Data Type} php-fpm-configuration
29240 Data Type for php-fpm service configuration.
29242 @item @code{php} (default: @code{php})
29243 The php package to use.
29244 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
29245 The address on which to accept FastCGI requests. Valid syntaxes are:
29247 @item @code{"ip.add.re.ss:port"}
29248 Listen on a TCP socket to a specific address on a specific port.
29249 @item @code{"port"}
29250 Listen on a TCP socket to all addresses on a specific port.
29251 @item @code{"/path/to/unix/socket"}
29252 Listen on a unix socket.
29255 @item @code{user} (default: @code{php-fpm})
29256 User who will own the php worker processes.
29257 @item @code{group} (default: @code{php-fpm})
29258 Group of the worker processes.
29259 @item @code{socket-user} (default: @code{php-fpm})
29260 User who can speak to the php-fpm socket.
29261 @item @code{socket-group} (default: @code{nginx})
29262 Group that can speak to the php-fpm socket.
29263 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
29264 The process id of the php-fpm process is written to this file
29265 once the service has started.
29266 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
29267 Log for the php-fpm master process.
29268 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
29269 Detailed settings for the php-fpm process manager.
29272 @item @code{<php-fpm-dynamic-process-manager-configuration>}
29273 @item @code{<php-fpm-static-process-manager-configuration>}
29274 @item @code{<php-fpm-on-demand-process-manager-configuration>}
29276 @item @code{display-errors} (default @code{#f})
29277 Determines whether php errors and warning should be sent to clients
29278 and displayed in their browsers.
29279 This is useful for local php development, but a security risk for public sites,
29280 as error messages can reveal passwords and personal data.
29281 @item @code{timezone} (default @code{#f})
29282 Specifies @code{php_admin_value[date.timezone]} parameter.
29283 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
29284 This file will log the @code{stderr} outputs of php worker processes.
29285 Can be set to @code{#f} to disable logging.
29286 @item @code{file} (default @code{#f})
29287 An optional override of the whole configuration.
29288 You can use the @code{mixed-text-file} function or an absolute filepath for it.
29289 @item @code{php-ini-file} (default @code{#f})
29290 An optional override of the default php settings.
29291 It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
29292 You can use the @code{mixed-text-file} function or an absolute filepath for it.
29294 For local development it is useful to set a higher timeout and memory
29295 limit for spawned php processes. This be accomplished with the
29296 following operating system configuration snippet:
29298 (define %local-php-ini
29299 (plain-file "php.ini"
29301 max_execution_time = 1800"))
29305 (services (cons (service php-fpm-service-type
29306 (php-fpm-configuration
29307 (php-ini-file %local-php-ini)))
29311 Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
29312 directives} for comprehensive documentation on the acceptable
29313 @file{php.ini} directives.
29317 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
29318 Data Type for the @code{dynamic} php-fpm process manager. With the
29319 @code{dynamic} process manager, spare worker processes are kept around
29320 based on its configured limits.
29322 @item @code{max-children} (default: @code{5})
29323 Maximum of worker processes.
29324 @item @code{start-servers} (default: @code{2})
29325 How many worker processes should be started on start-up.
29326 @item @code{min-spare-servers} (default: @code{1})
29327 How many spare worker processes should be kept around at minimum.
29328 @item @code{max-spare-servers} (default: @code{3})
29329 How many spare worker processes should be kept around at maximum.
29333 @deftp {Data type} php-fpm-static-process-manager-configuration
29334 Data Type for the @code{static} php-fpm process manager. With the
29335 @code{static} process manager, an unchanging number of worker processes
29338 @item @code{max-children} (default: @code{5})
29339 Maximum of worker processes.
29343 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
29344 Data Type for the @code{on-demand} php-fpm process manager. With the
29345 @code{on-demand} process manager, worker processes are only created as
29348 @item @code{max-children} (default: @code{5})
29349 Maximum of worker processes.
29350 @item @code{process-idle-timeout} (default: @code{10})
29351 The time in seconds after which a process with no requests is killed.
29356 @deffn {Scheme Procedure} nginx-php-location @
29357 [#:nginx-package nginx] @
29358 [socket (string-append "/var/run/php" @
29359 (version-major (package-version php)) @
29361 A helper function to quickly add php to an @code{nginx-server-configuration}.
29364 A simple services setup for nginx with php can look like this:
29366 (services (cons* (service dhcp-client-service-type)
29367 (service php-fpm-service-type)
29368 (service nginx-service-type
29369 (nginx-server-configuration
29370 (server-name '("example.com"))
29371 (root "/srv/http/")
29373 (list (nginx-php-location)))
29375 (ssl-certificate #f)
29376 (ssl-certificate-key #f)))
29380 @cindex cat-avatar-generator
29381 The cat avatar generator is a simple service to demonstrate the use of php-fpm
29382 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
29383 the hash of a user's email address.
29385 @deffn {Scheme Procedure} cat-avatar-generator-service @
29386 [#:cache-dir "/var/cache/cat-avatar-generator"] @
29387 [#:package cat-avatar-generator] @
29388 [#:configuration (nginx-server-configuration)]
29389 Returns an nginx-server-configuration that inherits @code{configuration}. It
29390 extends the nginx configuration to add a server block that serves @code{package},
29391 a version of cat-avatar-generator. During execution, cat-avatar-generator will
29392 be able to use @code{cache-dir} as its cache directory.
29395 A simple setup for cat-avatar-generator can look like this:
29397 (services (cons* (cat-avatar-generator-service
29399 (nginx-server-configuration
29400 (server-name '("example.com"))))
29405 @subsubheading Hpcguix-web
29407 @cindex hpcguix-web
29408 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
29409 program is a customizable web interface to browse Guix packages,
29410 initially designed for users of high-performance computing (HPC)
29413 @defvr {Scheme Variable} hpcguix-web-service-type
29414 The service type for @code{hpcguix-web}.
29417 @deftp {Data Type} hpcguix-web-configuration
29418 Data type for the hpcguix-web service configuration.
29422 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
29423 configuration. The main items available in this spec are:
29426 @item @code{title-prefix} (default: @code{"hpcguix | "})
29427 The page title prefix.
29429 @item @code{guix-command} (default: @code{"guix"})
29430 The @command{guix} command.
29432 @item @code{package-filter-proc} (default: @code{(const #t)})
29433 A procedure specifying how to filter packages that are displayed.
29435 @item @code{package-page-extension-proc} (default: @code{(const '())})
29436 Extension package for @code{hpcguix-web}.
29438 @item @code{menu} (default: @code{'()})
29439 Additional entry in page @code{menu}.
29441 @item @code{channels} (default: @code{%default-channels})
29442 List of channels from which the package list is built (@pxref{Channels}).
29444 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
29445 The expiration time, in seconds, after which the package list is rebuilt from
29446 the latest instances of the given channels.
29449 See the hpcguix-web repository for a
29450 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
29453 @item @code{package} (default: @code{hpcguix-web})
29454 The hpcguix-web package to use.
29456 @item @code{address} (default: @code{"127.0.0.1"})
29457 The IP address to listen to.
29459 @item @code{port} (default: @code{5000})
29460 The port number to listen to.
29464 A typical hpcguix-web service declaration looks like this:
29467 (service hpcguix-web-service-type
29468 (hpcguix-web-configuration
29470 #~(define site-config
29471 (hpcweb-configuration
29472 (title-prefix "Guix-HPC - ")
29473 (menu '(("/about" "ABOUT"))))))))
29477 The hpcguix-web service periodically updates the package list it publishes by
29478 pulling channels from Git. To that end, it needs to access X.509 certificates
29479 so that it can authenticate Git servers when communicating over HTTPS, and it
29480 assumes that @file{/etc/ssl/certs} contains those certificates.
29482 Thus, make sure to add @code{nss-certs} or another certificate package to the
29483 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
29484 more information on X.509 certificates.
29487 @subsubheading gmnisrv
29490 The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
29491 simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
29493 @deffn {Scheme Variable} gmnisrv-service-type
29494 This is the type of the gmnisrv service, whose value should be a
29495 @code{gmnisrv-configuration} object, as in this example:
29498 (service gmnisrv-service-type
29499 (gmnisrv-configuration
29500 (config-file (local-file "./my-gmnisrv.ini"))))
29504 @deftp {Data Type} gmnisrv-configuration
29505 Data type representing the configuration of gmnisrv.
29508 @item @code{package} (default: @var{gmnisrv})
29509 Package object of the gmnisrv server.
29511 @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
29512 File-like object of the gmnisrv configuration file to use. The default
29513 configuration listens on port 1965 and serves files from
29514 @file{/srv/gemini}. Certificates are stored in
29515 @file{/var/lib/gemini/certs}. For more information, run @command{man
29516 gmnisrv} and @command{man gmnisrv.ini}.
29521 @subsubheading Agate
29524 The @uref{gemini://qwertqwefsday.eu/agate.gmi, Agate}
29525 (@uref{https://github.com/mbrubeck/agate, GitHub page over HTTPS})
29526 program is a simple @uref{https://gemini.circumlunar.space/, Gemini}
29527 protocol server written in Rust.
29529 @deffn {Scheme Variable} agate-service-type
29530 This is the type of the agate service, whose value should be an
29531 @code{agate-service-type} object, as in this example:
29534 (service agate-service-type
29535 (agate-configuration
29536 (content "/srv/gemini")
29537 (cert "/srv/cert.pem")
29538 (key "/srv/key.rsa")))
29541 The example above represents the minimal tweaking necessary to get Agate
29542 up and running. Specifying the path to the certificate and key is
29543 always necessary, as the Gemini protocol requires TLS by default.
29545 To obtain a certificate and a key, you could, for example, use OpenSSL,
29546 running a command similar to the following example:
29549 openssl req -x509 -newkey rsa:4096 -keyout key.rsa -out cert.pem \
29550 -days 3650 -nodes -subj "/CN=example.com"
29553 Of course, you'll have to replace @i{example.com} with your own domain
29554 name, and then point the Agate configuration towards the path of the
29555 generated key and certificate.
29559 @deftp {Data Type} agate-configuration
29560 Data type representing the configuration of Agate.
29563 @item @code{package} (default: @code{agate})
29564 The package object of the Agate server.
29566 @item @code{content} (default: @file{"/srv/gemini"})
29567 The directory from which Agate will serve files.
29569 @item @code{cert} (default: @code{#f})
29570 The path to the TLS certificate PEM file to be used for encrypted
29571 connections. Must be filled in with a value from the user.
29573 @item @code{key} (default: @code{#f})
29574 The path to the PKCS8 private key file to be used for encrypted
29575 connections. Must be filled in with a value from the user.
29577 @item @code{addr} (default: @code{'("0.0.0.0:1965" "[::]:1965")})
29578 A list of the addresses to listen on.
29580 @item @code{hostname} (default: @code{#f})
29581 The domain name of this Gemini server. Optional.
29583 @item @code{lang} (default: @code{#f})
29584 RFC 4646 language code(s) for text/gemini documents. Optional.
29586 @item @code{silent?} (default: @code{#f})
29587 Set to @code{#t} to disable logging output.
29589 @item @code{serve-secret?} (default: @code{#f})
29590 Set to @code{#t} to serve secret files (files/directories starting with
29593 @item @code{log-ip?} (default: @code{#t})
29594 Whether or not to output IP addresses when logging.
29596 @item @code{user} (default: @code{"agate"})
29597 Owner of the @code{agate} process.
29599 @item @code{group} (default: @code{"agate"})
29600 Owner's group of the @code{agate} process.
29602 @item @code{log-file} (default: @file{"/var/log/agate.log"})
29603 The file which should store the logging output of Agate.
29608 @node Certificate Services
29609 @subsection Certificate Services
29612 @cindex HTTP, HTTPS
29613 @cindex Let's Encrypt
29614 @cindex TLS certificates
29615 The @code{(gnu services certbot)} module provides a service to
29616 automatically obtain a valid TLS certificate from the Let's Encrypt
29617 certificate authority. These certificates can then be used to serve
29618 content securely over HTTPS or other TLS-based protocols, with the
29619 knowledge that the client will be able to verify the server's
29622 @url{https://letsencrypt.org/, Let's Encrypt} provides the
29623 @code{certbot} tool to automate the certification process. This tool
29624 first securely generates a key on the server. It then makes a request
29625 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
29626 checks that the request originates from the host in question by using a
29627 challenge-response protocol, requiring the server to provide its
29628 response over HTTP@. If that protocol completes successfully, the CA
29629 signs the key, resulting in a certificate. That certificate is valid
29630 for a limited period of time, and therefore to continue to provide TLS
29631 services, the server needs to periodically ask the CA to renew its
29634 The certbot service automates this process: the initial key
29635 generation, the initial certification request to the Let's Encrypt
29636 service, the web server challenge/response integration, writing the
29637 certificate to disk, the automated periodic renewals, and the deployment
29638 tasks associated with the renewal (e.g.@: reloading services, copying keys
29639 with different permissions).
29641 Certbot is run twice a day, at a random minute within the hour. It
29642 won't do anything until your certificates are due for renewal or
29643 revoked, but running it regularly would give your service a chance of
29644 staying online in case a Let's Encrypt-initiated revocation happened for
29647 By using this service, you agree to the ACME Subscriber Agreement, which
29648 can be found there:
29649 @url{https://acme-v01.api.letsencrypt.org/directory}.
29651 @defvr {Scheme Variable} certbot-service-type
29652 A service type for the @code{certbot} Let's Encrypt client. Its value
29653 must be a @code{certbot-configuration} record as in this example:
29656 (define %nginx-deploy-hook
29658 "nginx-deploy-hook"
29659 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
29660 (kill pid SIGHUP))))
29662 (service certbot-service-type
29663 (certbot-configuration
29664 (email "foo@@example.net")
29667 (certificate-configuration
29668 (domains '("example.net" "www.example.net"))
29669 (deploy-hook %nginx-deploy-hook))
29670 (certificate-configuration
29671 (domains '("bar.example.net")))))))
29674 See below for details about @code{certbot-configuration}.
29677 @deftp {Data Type} certbot-configuration
29678 Data type representing the configuration of the @code{certbot} service.
29679 This type has the following parameters:
29682 @item @code{package} (default: @code{certbot})
29683 The certbot package to use.
29685 @item @code{webroot} (default: @code{/var/www})
29686 The directory from which to serve the Let's Encrypt challenge/response
29689 @item @code{certificates} (default: @code{()})
29690 A list of @code{certificates-configuration}s for which to generate
29691 certificates and request signatures. Each certificate has a @code{name}
29692 and several @code{domains}.
29694 @item @code{email} (default: @code{#f})
29695 Optional email address used for registration and recovery contact.
29696 Setting this is encouraged as it allows you to receive important
29697 notifications about the account and issued certificates.
29699 @item @code{server} (default: @code{#f})
29700 Optional URL of ACME server. Setting this overrides certbot's default,
29701 which is the Let's Encrypt server.
29703 @item @code{rsa-key-size} (default: @code{2048})
29704 Size of the RSA key.
29706 @item @code{default-location} (default: @i{see below})
29707 The default @code{nginx-location-configuration}. Because @code{certbot}
29708 needs to be able to serve challenges and responses, it needs to be able
29709 to run a web server. It does so by extending the @code{nginx} web
29710 service with an @code{nginx-server-configuration} listening on the
29711 @var{domains} on port 80, and which has a
29712 @code{nginx-location-configuration} for the @code{/.well-known/} URI
29713 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
29714 these nginx configuration data types.
29716 Requests to other URL paths will be matched by the
29717 @code{default-location}, which if present is added to all
29718 @code{nginx-server-configuration}s.
29720 By default, the @code{default-location} will issue a redirect from
29721 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
29722 you to define what to serve on your site via @code{https}.
29724 Pass @code{#f} to not issue a default location.
29728 @deftp {Data Type} certificate-configuration
29729 Data type representing the configuration of a certificate.
29730 This type has the following parameters:
29733 @item @code{name} (default: @i{see below})
29734 This name is used by Certbot for housekeeping and in file paths; it
29735 doesn't affect the content of the certificate itself. To see
29736 certificate names, run @code{certbot certificates}.
29738 Its default is the first provided domain.
29740 @item @code{domains} (default: @code{()})
29741 The first domain provided will be the subject CN of the certificate, and
29742 all domains will be Subject Alternative Names on the certificate.
29744 @item @code{challenge} (default: @code{#f})
29745 The challenge type that has to be run by certbot. If @code{#f} is specified,
29746 default to the HTTP challenge. If a value is specified, defaults to the
29747 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
29748 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
29749 and gives Let's Encrypt permission to log the public IP address of the
29750 requesting machine.
29752 @item @code{csr} (default: @code{#f})
29753 File name of Certificate Signing Request (CSR) in DER or PEM format.
29754 If @code{#f} is specified, this argument will not be passed to certbot.
29755 If a value is specified, certbot will use it to obtain a certificate, instead of
29756 using a self-generated CSR.
29757 The domain-name(s) mentioned in @code{domains}, must be consistent with the
29758 domain-name(s) mentioned in CSR file.
29760 @item @code{authentication-hook} (default: @code{#f})
29761 Command to be run in a shell once for each certificate challenge to be
29762 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
29763 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
29764 contains the validation string and @code{$CERTBOT_TOKEN} contains the
29765 file name of the resource requested when performing an HTTP-01 challenge.
29767 @item @code{cleanup-hook} (default: @code{#f})
29768 Command to be run in a shell once for each certificate challenge that
29769 have been answered by the @code{auth-hook}. For this command, the shell
29770 variables available in the @code{auth-hook} script are still available, and
29771 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
29772 of the @code{auth-hook} script.
29774 @item @code{deploy-hook} (default: @code{#f})
29775 Command to be run in a shell once for each successfully issued
29776 certificate. For this command, the shell variable
29777 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
29778 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
29779 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
29780 contain a space-delimited list of renewed certificate domains (for
29781 example, @samp{"example.com www.example.com"}.
29786 For each @code{certificate-configuration}, the certificate is saved to
29787 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
29788 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
29790 @subsection DNS Services
29791 @cindex DNS (domain name system)
29792 @cindex domain name system (DNS)
29794 The @code{(gnu services dns)} module provides services related to the
29795 @dfn{domain name system} (DNS). It provides a server service for hosting
29796 an @emph{authoritative} DNS server for multiple zones, slave or master.
29797 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
29798 caching and forwarding DNS server for the LAN, which uses
29799 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
29801 @subsubheading Knot Service
29803 An example configuration of an authoritative server for two zones, one master
29807 (define-zone-entries example.org.zone
29808 ;; Name TTL Class Type Data
29809 ("@@" "" "IN" "A" "127.0.0.1")
29810 ("@@" "" "IN" "NS" "ns")
29811 ("ns" "" "IN" "A" "127.0.0.1"))
29813 (define master-zone
29814 (knot-zone-configuration
29815 (domain "example.org")
29817 (origin "example.org")
29818 (entries example.org.zone)))))
29821 (knot-zone-configuration
29822 (domain "plop.org")
29823 (dnssec-policy "default")
29824 (master (list "plop-master"))))
29826 (define plop-master
29827 (knot-remote-configuration
29829 (address (list "208.76.58.171"))))
29833 (services (cons* (service knot-service-type
29834 (knot-configuration
29835 (remotes (list plop-master))
29836 (zones (list master-zone slave-zone))))
29841 @deffn {Scheme Variable} knot-service-type
29842 This is the type for the Knot DNS server.
29844 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
29845 zones, that is to say domain names you would buy from a registrar. This server
29846 is not a resolver, meaning that it can only resolve names for which it is
29847 authoritative. This server can be configured to serve zones as a master server
29848 or a slave server as a per-zone basis. Slave zones will get their data from
29849 masters, and will serve it as an authoritative server. From the point of view
29850 of a resolver, there is no difference between master and slave.
29852 The following data types are used to configure the Knot DNS server:
29855 @deftp {Data Type} knot-key-configuration
29856 Data type representing a key.
29857 This type has the following parameters:
29860 @item @code{id} (default: @code{""})
29861 An identifier for other configuration fields to refer to this key. IDs must
29862 be unique and must not be empty.
29864 @item @code{algorithm} (default: @code{#f})
29865 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
29866 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
29867 and @code{'hmac-sha512}.
29869 @item @code{secret} (default: @code{""})
29870 The secret key itself.
29875 @deftp {Data Type} knot-acl-configuration
29876 Data type representing an Access Control List (ACL) configuration.
29877 This type has the following parameters:
29880 @item @code{id} (default: @code{""})
29881 An identifier for other configuration fields to refer to this key. IDs must be
29882 unique and must not be empty.
29884 @item @code{address} (default: @code{'()})
29885 An ordered list of IP addresses, network subnets, or network ranges represented
29886 with strings. The query must match one of them. Empty value means that
29887 address match is not required.
29889 @item @code{key} (default: @code{'()})
29890 An ordered list of references to keys represented with strings. The string
29891 must match a key ID defined in a @code{knot-key-configuration}. No key means
29892 that a key is not require to match that ACL.
29894 @item @code{action} (default: @code{'()})
29895 An ordered list of actions that are permitted or forbidden by this ACL@. Possible
29896 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
29897 and @code{'update}.
29899 @item @code{deny?} (default: @code{#f})
29900 When true, the ACL defines restrictions. Listed actions are forbidden. When
29901 false, listed actions are allowed.
29906 @deftp {Data Type} zone-entry
29907 Data type representing a record entry in a zone file.
29908 This type has the following parameters:
29911 @item @code{name} (default: @code{"@@"})
29912 The name of the record. @code{"@@"} refers to the origin of the zone. Names
29913 are relative to the origin of the zone. For example, in the @code{example.org}
29914 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
29915 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
29916 refers to @code{ns.example.org}.
29918 @item @code{ttl} (default: @code{""})
29919 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
29921 @item @code{class} (default: @code{"IN"})
29922 The class of the record. Knot currently supports only @code{"IN"} and
29923 partially @code{"CH"}.
29925 @item @code{type} (default: @code{"A"})
29926 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
29927 address), NS (Name Server) and MX (Mail eXchange). Many other types are
29930 @item @code{data} (default: @code{""})
29931 The data contained in the record. For instance an IP address associated with
29932 an A record, or a domain name associated with an NS record. Remember that
29933 domain names are relative to the origin unless they end with a dot.
29938 @deftp {Data Type} zone-file
29939 Data type representing the content of a zone file.
29940 This type has the following parameters:
29943 @item @code{entries} (default: @code{'()})
29944 The list of entries. The SOA record is taken care of, so you don't need to
29945 put it in the list of entries. This list should probably contain an entry
29946 for your primary authoritative DNS server. Other than using a list of entries
29947 directly, you can use @code{define-zone-entries} to define a object containing
29948 the list of entries more easily, that you can later pass to the @code{entries}
29949 field of the @code{zone-file}.
29951 @item @code{origin} (default: @code{""})
29952 The name of your zone. This parameter cannot be empty.
29954 @item @code{ns} (default: @code{"ns"})
29955 The domain of your primary authoritative DNS server. The name is relative to
29956 the origin, unless it ends with a dot. It is mandatory that this primary
29957 DNS server corresponds to an NS record in the zone and that it is associated
29958 to an IP address in the list of entries.
29960 @item @code{mail} (default: @code{"hostmaster"})
29961 An email address people can contact you at, as the owner of the zone. This
29962 is translated as @code{<mail>@@<origin>}.
29964 @item @code{serial} (default: @code{1})
29965 The serial number of the zone. As this is used to keep track of changes by
29966 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
29967 Always increment it when you make a change in your zone.
29969 @item @code{refresh} (default: @code{(* 2 24 3600)})
29970 The frequency at which slaves will do a zone transfer. This value is a number
29971 of seconds. It can be computed by multiplications or with
29972 @code{(string->duration)}.
29974 @item @code{retry} (default: @code{(* 15 60)})
29975 The period after which a slave will retry to contact its master when it fails
29976 to do so a first time.
29978 @item @code{expiry} (default: @code{(* 14 24 3600)})
29979 Default TTL of records. Existing records are considered correct for at most
29980 this amount of time. After this period, resolvers will invalidate their cache
29981 and check again that it still exists.
29983 @item @code{nx} (default: @code{3600})
29984 Default TTL of inexistent records. This delay is usually short because you want
29985 your new domains to reach everyone quickly.
29990 @deftp {Data Type} knot-remote-configuration
29991 Data type representing a remote configuration.
29992 This type has the following parameters:
29995 @item @code{id} (default: @code{""})
29996 An identifier for other configuration fields to refer to this remote. IDs must
29997 be unique and must not be empty.
29999 @item @code{address} (default: @code{'()})
30000 An ordered list of destination IP addresses. Addresses are tried in sequence.
30001 An optional port can be given with the @@ separator. For instance:
30002 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
30004 @item @code{via} (default: @code{'()})
30005 An ordered list of source IP addresses. An empty list will have Knot choose
30006 an appropriate source IP@. An optional port can be given with the @@ separator.
30007 The default is to choose at random.
30009 @item @code{key} (default: @code{#f})
30010 A reference to a key, that is a string containing the identifier of a key
30011 defined in a @code{knot-key-configuration} field.
30016 @deftp {Data Type} knot-keystore-configuration
30017 Data type representing a keystore to hold dnssec keys.
30018 This type has the following parameters:
30021 @item @code{id} (default: @code{""})
30022 The id of the keystore. It must not be empty.
30024 @item @code{backend} (default: @code{'pem})
30025 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
30027 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
30028 The configuration string of the backend. An example for the PKCS#11 is:
30029 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
30030 For the pem backend, the string represents a path in the file system.
30035 @deftp {Data Type} knot-policy-configuration
30036 Data type representing a dnssec policy. Knot DNS is able to automatically
30037 sign your zones. It can either generate and manage your keys automatically or
30038 use keys that you generate.
30040 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
30041 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
30042 zone. In order to be trusted, the KSK needs to be present in the parent zone
30043 (usually a top-level domain). If your registrar supports dnssec, you will
30044 have to send them your KSK's hash so they can add a DS record in their zone.
30045 This is not automated and need to be done each time you change your KSK.
30047 The policy also defines the lifetime of keys. Usually, ZSK can be changed
30048 easily and use weaker cryptographic functions (they use lower parameters) in
30049 order to sign records quickly, so they are changed often. The KSK however
30050 requires manual interaction with the registrar, so they are changed less often
30051 and use stronger parameters because they sign only one record.
30053 This type has the following parameters:
30056 @item @code{id} (default: @code{""})
30057 The id of the policy. It must not be empty.
30059 @item @code{keystore} (default: @code{"default"})
30060 A reference to a keystore, that is a string containing the identifier of a
30061 keystore defined in a @code{knot-keystore-configuration} field. The
30062 @code{"default"} identifier means the default keystore (a kasp database that
30063 was setup by this service).
30065 @item @code{manual?} (default: @code{#f})
30066 Whether the key management is manual or automatic.
30068 @item @code{single-type-signing?} (default: @code{#f})
30069 When @code{#t}, use the Single-Type Signing Scheme.
30071 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
30072 An algorithm of signing keys and issued signatures.
30074 @item @code{ksk-size} (default: @code{256})
30075 The length of the KSK@. Note that this value is correct for the default
30076 algorithm, but would be unsecure for other algorithms.
30078 @item @code{zsk-size} (default: @code{256})
30079 The length of the ZSK@. Note that this value is correct for the default
30080 algorithm, but would be unsecure for other algorithms.
30082 @item @code{dnskey-ttl} (default: @code{'default})
30083 The TTL value for DNSKEY records added into zone apex. The special
30084 @code{'default} value means same as the zone SOA TTL.
30086 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
30087 The period between ZSK publication and the next rollover initiation.
30089 @item @code{propagation-delay} (default: @code{(* 24 3600)})
30090 An extra delay added for each key rollover step. This value should be high
30091 enough to cover propagation of data from the master server to all slaves.
30093 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
30094 A validity period of newly issued signatures.
30096 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
30097 A period how long before a signature expiration the signature will be refreshed.
30099 @item @code{nsec3?} (default: @code{#f})
30100 When @code{#t}, NSEC3 will be used instead of NSEC.
30102 @item @code{nsec3-iterations} (default: @code{5})
30103 The number of additional times the hashing is performed.
30105 @item @code{nsec3-salt-length} (default: @code{8})
30106 The length of a salt field in octets, which is appended to the original owner
30107 name before hashing.
30109 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
30110 The validity period of newly issued salt field.
30115 @deftp {Data Type} knot-zone-configuration
30116 Data type representing a zone served by Knot.
30117 This type has the following parameters:
30120 @item @code{domain} (default: @code{""})
30121 The domain served by this configuration. It must not be empty.
30123 @item @code{file} (default: @code{""})
30124 The file where this zone is saved. This parameter is ignored by master zones.
30125 Empty means default location that depends on the domain name.
30127 @item @code{zone} (default: @code{(zone-file)})
30128 The content of the zone file. This parameter is ignored by slave zones. It
30129 must contain a zone-file record.
30131 @item @code{master} (default: @code{'()})
30132 A list of master remotes. When empty, this zone is a master. When set, this
30133 zone is a slave. This is a list of remotes identifiers.
30135 @item @code{ddns-master} (default: @code{#f})
30136 The main master. When empty, it defaults to the first master in the list of
30139 @item @code{notify} (default: @code{'()})
30140 A list of slave remote identifiers.
30142 @item @code{acl} (default: @code{'()})
30143 A list of acl identifiers.
30145 @item @code{semantic-checks?} (default: @code{#f})
30146 When set, this adds more semantic checks to the zone.
30148 @item @code{zonefile-sync} (default: @code{0})
30149 The delay between a modification in memory and on disk. 0 means immediate
30152 @item @code{zonefile-load} (default: @code{#f})
30153 The way the zone file contents are applied during zone load. Possible values
30157 @item @code{#f} for using the default value from Knot,
30158 @item @code{'none} for not using the zone file at all,
30159 @item @code{'difference} for computing the difference between already available
30160 contents and zone contents and applying it to the current zone contents,
30161 @item @code{'difference-no-serial} for the same as @code{'difference}, but
30162 ignoring the SOA serial in the zone file, while the server takes care of it
30164 @item @code{'whole} for loading zone contents from the zone file.
30167 @item @code{journal-content} (default: @code{#f})
30168 The way the journal is used to store zone and its changes. Possible values
30169 are @code{'none} to not use it at all, @code{'changes} to store changes and
30170 @code{'all} to store contents. @code{#f} does not set this option, so the
30171 default value from Knot is used.
30173 @item @code{max-journal-usage} (default: @code{#f})
30174 The maximum size for the journal on disk. @code{#f} does not set this option,
30175 so the default value from Knot is used.
30177 @item @code{max-journal-depth} (default: @code{#f})
30178 The maximum size of the history. @code{#f} does not set this option, so the
30179 default value from Knot is used.
30181 @item @code{max-zone-size} (default: @code{#f})
30182 The maximum size of the zone file. This limit is enforced for incoming
30183 transfer and updates. @code{#f} does not set this option, so the default
30184 value from Knot is used.
30186 @item @code{dnssec-policy} (default: @code{#f})
30187 A reference to a @code{knot-policy-configuration} record, or the special
30188 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
30191 @item @code{serial-policy} (default: @code{'increment})
30192 A policy between @code{'increment} and @code{'unixtime}.
30197 @deftp {Data Type} knot-configuration
30198 Data type representing the Knot configuration.
30199 This type has the following parameters:
30202 @item @code{knot} (default: @code{knot})
30205 @item @code{run-directory} (default: @code{"/var/run/knot"})
30206 The run directory. This directory will be used for pid file and sockets.
30208 @item @code{includes} (default: @code{'()})
30209 A list of strings or file-like objects denoting other files that must be
30210 included at the top of the configuration file.
30212 @cindex secrets, Knot service
30213 This can be used to manage secrets out-of-band. For example, secret
30214 keys may be stored in an out-of-band file not managed by Guix, and
30215 thus not visible in @file{/gnu/store}---e.g., you could store secret
30216 key configuration in @file{/etc/knot/secrets.conf} and add this file
30217 to the @code{includes} list.
30219 One can generate a secret tsig key (for nsupdate and zone transfers with the
30220 keymgr command from the knot package. Note that the package is not automatically
30221 installed by the service. The following example shows how to generate a new
30225 keymgr -t mysecret > /etc/knot/secrets.conf
30226 chmod 600 /etc/knot/secrets.conf
30229 Also note that the generated key will be named @var{mysecret}, so it is the
30230 name that needs to be used in the @var{key} field of the
30231 @code{knot-acl-configuration} record and in other places that need to refer
30234 It can also be used to add configuration not supported by this interface.
30236 @item @code{listen-v4} (default: @code{"0.0.0.0"})
30237 An ip address on which to listen.
30239 @item @code{listen-v6} (default: @code{"::"})
30240 An ip address on which to listen.
30242 @item @code{listen-port} (default: @code{53})
30243 A port on which to listen.
30245 @item @code{keys} (default: @code{'()})
30246 The list of knot-key-configuration used by this configuration.
30248 @item @code{acls} (default: @code{'()})
30249 The list of knot-acl-configuration used by this configuration.
30251 @item @code{remotes} (default: @code{'()})
30252 The list of knot-remote-configuration used by this configuration.
30254 @item @code{zones} (default: @code{'()})
30255 The list of knot-zone-configuration used by this configuration.
30260 @subsubheading Knot Resolver Service
30262 @deffn {Scheme Variable} knot-resolver-service-type
30263 This is the type of the knot resolver service, whose value should be
30264 an @code{knot-resolver-configuration} object as in this example:
30267 (service knot-resolver-service-type
30268 (knot-resolver-configuration
30269 (kresd-config-file (plain-file "kresd.conf" "
30270 net.listen('192.168.0.1', 5353)
30271 user('knot-resolver', 'knot-resolver')
30272 modules = @{ 'hints > iterate', 'stats', 'predict' @}
30273 cache.size = 100 * MB
30277 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
30280 @deftp {Data Type} knot-resolver-configuration
30281 Data type representing the configuration of knot-resolver.
30284 @item @code{package} (default: @var{knot-resolver})
30285 Package object of the knot DNS resolver.
30287 @item @code{kresd-config-file} (default: %kresd.conf)
30288 File-like object of the kresd configuration file to use, by default it
30289 will listen on @code{127.0.0.1} and @code{::1}.
30291 @item @code{garbage-collection-interval} (default: 1000)
30292 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
30298 @subsubheading Dnsmasq Service
30300 @deffn {Scheme Variable} dnsmasq-service-type
30301 This is the type of the dnsmasq service, whose value should be an
30302 @code{dnsmasq-configuration} object as in this example:
30305 (service dnsmasq-service-type
30306 (dnsmasq-configuration
30308 (servers '("192.168.1.1"))))
30312 @deftp {Data Type} dnsmasq-configuration
30313 Data type representing the configuration of dnsmasq.
30316 @item @code{package} (default: @var{dnsmasq})
30317 Package object of the dnsmasq server.
30319 @item @code{no-hosts?} (default: @code{#f})
30320 When true, don't read the hostnames in /etc/hosts.
30322 @item @code{port} (default: @code{53})
30323 The port to listen on. Setting this to zero completely disables DNS
30324 responses, leaving only DHCP and/or TFTP functions.
30326 @item @code{local-service?} (default: @code{#t})
30327 Accept DNS queries only from hosts whose address is on a local subnet,
30328 ie a subnet for which an interface exists on the server.
30330 @item @code{listen-addresses} (default: @code{'()})
30331 Listen on the given IP addresses.
30333 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
30334 The file to read the IP address of the upstream nameservers from.
30336 @item @code{no-resolv?} (default: @code{#f})
30337 When true, don't read @var{resolv-file}.
30339 @item @code{forward-private-reverse-lookup?} (default: @code{#t})
30340 When false, all reverse lookups for private IP ranges are answered with
30341 "no such domain" rather than being forwarded upstream.
30343 @item @code{query-servers-in-order?} (default: @code{#f})
30344 When true, dnsmasq queries the servers in the same order as they appear
30347 @item @code{servers} (default: @code{'()})
30348 Specify IP address of upstream servers directly.
30350 @item @code{addresses} (default: @code{'()})
30351 For each entry, specify an IP address to return for any host in the
30352 given domains. Queries in the domains are never forwarded and always
30353 replied to with the specified IP address.
30355 This is useful for redirecting hosts locally, for example:
30358 (service dnsmasq-service-type
30359 (dnsmasq-configuration
30361 '(; Redirect to a local web-server.
30362 "/example.org/127.0.0.1"
30363 ; Redirect subdomain to a specific IP.
30364 "/subdomain.example.org/192.168.1.42"))))
30367 Note that rules in @file{/etc/hosts} take precedence over this.
30369 @item @code{cache-size} (default: @code{150})
30370 Set the size of dnsmasq's cache. Setting the cache size to zero
30373 @item @code{negative-cache?} (default: @code{#t})
30374 When false, disable negative caching.
30376 @item @code{cpe-id} (default: @code{#f})
30377 If set, add a CPE (Customer-Premises Equipment) identifier to DNS
30378 queries which are forwarded upstream.
30380 @item @code{tftp-enable?} (default: @code{#f})
30381 Whether to enable the built-in TFTP server.
30383 @item @code{tftp-no-fail?} (default: @code{#f})
30384 If true, does not fail dnsmasq if the TFTP server could not start up.
30386 @item @code{tftp-single-port?} (default: @code{#f})
30387 Whether to use only one single port for TFTP.
30389 @item @code{tftp-secure?} (default: @code{#f})
30390 If true, only files owned by the user running the dnsmasq process are accessible.
30392 If dnsmasq is being run as root, different rules apply:
30393 @code{tftp-secure?} has no effect, but only files which have the
30394 world-readable bit set are accessible.
30396 @item @code{tftp-max} (default: @code{#f})
30397 If set, sets the maximal number of concurrent connections allowed.
30399 @item @code{tftp-mtu} (default: @code{#f})
30400 If set, sets the MTU for TFTP packets to that value.
30402 @item @code{tftp-no-blocksize?} (default: @code{#f})
30403 If true, stops the TFTP server from negotiating the blocksize with a client.
30405 @item @code{tftp-lowercase?} (default: @code{#f})
30406 Whether to convert all filenames in TFTP requests to lowercase.
30408 @item @code{tftp-port-range} (default: @code{#f})
30409 If set, fixes the dynamical ports (one per client) to the given range
30410 (@code{"<start>,<end>"}).
30412 @item @code{tftp-root} (default: @code{/var/empty,lo})
30413 Look for files to transfer using TFTP relative to the given directory.
30414 When this is set, TFTP paths which include @samp{..} are rejected, to stop clients
30415 getting outside the specified root. Absolute paths (starting with @samp{/}) are
30416 allowed, but they must be within the TFTP-root. If the optional interface
30417 argument is given, the directory is only used for TFTP requests via that
30420 @item @code{tftp-unique-root} (default: @code{#f})
30421 If set, add the IP or hardware address of the TFTP client as a path component
30422 on the end of the TFTP-root. Only valid if a TFTP root is set and the
30423 directory exists. Defaults to adding IP address (in standard dotted-quad
30426 For instance, if @option{--tftp-root} is @samp{/tftp} and client
30427 @samp{1.2.3.4} requests file @file{myfile} then the effective path will
30428 be @file{/tftp/1.2.3.4/myfile} if @file{/tftp/1.2.3.4} exists or
30429 @file{/tftp/myfile} otherwise. When @samp{=mac} is specified it will
30430 append the MAC address instead, using lowercase zero padded digits
30431 separated by dashes, e.g.: @samp{01-02-03-04-aa-bb}. Note that
30432 resolving MAC addresses is only possible if the client is in the local
30433 network or obtained a DHCP lease from dnsmasq.
30438 @subsubheading ddclient Service
30441 The ddclient service described below runs the ddclient daemon, which takes
30442 care of automatically updating DNS entries for service providers such as
30443 @uref{https://dyn.com/dns/, Dyn}.
30445 The following example show instantiates the service with its default
30449 (service ddclient-service-type)
30452 Note that ddclient needs to access credentials that are stored in a
30453 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
30454 @code{secret-file} below). You are expected to create this file manually, in
30455 an ``out-of-band'' fashion (you @emph{could} make this file part of the
30456 service configuration, for instance by using @code{plain-file}, but it will be
30457 world-readable @i{via} @file{/gnu/store}). See the examples in the
30458 @file{share/ddclient} directory of the @code{ddclient} package.
30460 @c %start of fragment
30462 Available @code{ddclient-configuration} fields are:
30464 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
30465 The ddclient package.
30469 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
30470 The period after which ddclient will retry to check IP and domain name.
30472 Defaults to @samp{300}.
30476 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
30477 Use syslog for the output.
30479 Defaults to @samp{#t}.
30483 @deftypevr {@code{ddclient-configuration} parameter} string mail
30486 Defaults to @samp{"root"}.
30490 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
30491 Mail failed update to user.
30493 Defaults to @samp{"root"}.
30497 @deftypevr {@code{ddclient-configuration} parameter} string pid
30498 The ddclient PID file.
30500 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
30504 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
30505 Enable SSL support.
30507 Defaults to @samp{#t}.
30511 @deftypevr {@code{ddclient-configuration} parameter} string user
30512 Specifies the user name or ID that is used when running ddclient
30515 Defaults to @samp{"ddclient"}.
30519 @deftypevr {@code{ddclient-configuration} parameter} string group
30520 Group of the user who will run the ddclient program.
30522 Defaults to @samp{"ddclient"}.
30526 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
30527 Secret file which will be appended to @file{ddclient.conf} file. This
30528 file contains credentials for use by ddclient. You are expected to
30529 create it manually.
30531 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
30535 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
30536 Extra options will be appended to @file{ddclient.conf} file.
30538 Defaults to @samp{()}.
30543 @c %end of fragment
30547 @subsection VPN Services
30548 @cindex VPN (virtual private network)
30549 @cindex virtual private network (VPN)
30551 The @code{(gnu services vpn)} module provides services related to
30552 @dfn{virtual private networks} (VPNs).
30554 @subsubheading Bitmask
30556 @defvr {Scheme Variable} bitmask-service-type
30557 A service type for the @uref{https://bitmask.net, Bitmask} VPN client. It makes
30558 the client available in the system and loads its polkit policy. Please note that
30559 the client expects an active polkit-agent, which is either run by your
30560 desktop-environment or should be run manually.
30563 @subsubheading OpenVPN
30565 It provides a @emph{client} service for your machine to connect to a
30566 VPN, and a @emph{server} service for your machine to host a VPN@.
30568 @deffn {Scheme Procedure} openvpn-client-service @
30569 [#:config (openvpn-client-configuration)]
30571 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
30574 @deffn {Scheme Procedure} openvpn-server-service @
30575 [#:config (openvpn-server-configuration)]
30577 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
30579 Both can be run simultaneously.
30582 @c %automatically generated documentation
30584 @deftp {Data Type} openvpn-client-configuration
30585 Available @code{openvpn-client-configuration} fields are:
30588 @item @code{openvpn} (default: @code{openvpn}) (type: file-like)
30589 The OpenVPN package.
30591 @item @code{pid-file} (default: @code{"/var/run/openvpn/openvpn.pid"}) (type: string)
30592 The OpenVPN pid file.
30594 @item @code{proto} (default: @code{udp}) (type: proto)
30595 The protocol (UDP or TCP) used to open a channel between clients and
30598 @item @code{dev} (default: @code{tun}) (type: dev)
30599 The device type used to represent the VPN connection.
30601 @item @code{ca} (default: @code{"/etc/openvpn/ca.crt"}) (type: maybe-string)
30602 The certificate authority to check connections against.
30604 @item @code{cert} (default: @code{"/etc/openvpn/client.crt"}) (type: maybe-string)
30605 The certificate of the machine the daemon is running on. It should be
30606 signed by the authority given in @code{ca}.
30608 @item @code{key} (default: @code{"/etc/openvpn/client.key"}) (type: maybe-string)
30609 The key of the machine the daemon is running on. It must be the key
30610 whose certificate is @code{cert}.
30612 @item @code{comp-lzo?} (default: @code{#t}) (type: boolean)
30613 Whether to use the lzo compression algorithm.
30615 @item @code{persist-key?} (default: @code{#t}) (type: boolean)
30616 Don't re-read key files across SIGUSR1 or --ping-restart.
30618 @item @code{persist-tun?} (default: @code{#t}) (type: boolean)
30619 Don't close and reopen TUN/TAP device or run up/down scripts across
30620 SIGUSR1 or --ping-restart restarts.
30622 @item @code{fast-io?} (default: @code{#f}) (type: boolean)
30623 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
30624 poll/epoll/select prior to the write operation.
30626 @item @code{verbosity} (default: @code{3}) (type: number)
30629 @item @code{tls-auth} (default: @code{#f}) (type: tls-auth-client)
30630 Add an additional layer of HMAC authentication on top of the TLS control
30631 channel to protect against DoS attacks.
30633 @item @code{auth-user-pass} (type: maybe-string)
30634 Authenticate with server using username/password. The option is a file
30635 containing username/password on 2 lines. Do not use a file-like object
30636 as it would be added to the store and readable by any user.
30638 @item @code{verify-key-usage?} (default: @code{#t}) (type: key-usage)
30639 Whether to check the server certificate has server usage extension.
30641 @item @code{bind?} (default: @code{#f}) (type: bind)
30642 Bind to a specific local port number.
30644 @item @code{resolv-retry?} (default: @code{#t}) (type: resolv-retry)
30645 Retry resolving server address.
30647 @item @code{remote} (default: @code{()}) (type: openvpn-remote-list)
30648 A list of remote servers to connect to.
30650 @deftp {Data Type} openvpn-remote-configuration
30651 Available @code{openvpn-remote-configuration} fields are:
30654 @item @code{name} (default: @code{"my-server"}) (type: string)
30657 @item @code{port} (default: @code{1194}) (type: number)
30658 Port number the server listens to.
30668 @c %end of automatic openvpn-client documentation
30670 @c %automatically generated documentation
30672 @deftp {Data Type} openvpn-server-configuration
30673 Available @code{openvpn-server-configuration} fields are:
30676 @item @code{openvpn} (default: @code{openvpn}) (type: file-like)
30677 The OpenVPN package.
30679 @item @code{pid-file} (default: @code{"/var/run/openvpn/openvpn.pid"}) (type: string)
30680 The OpenVPN pid file.
30682 @item @code{proto} (default: @code{udp}) (type: proto)
30683 The protocol (UDP or TCP) used to open a channel between clients and
30686 @item @code{dev} (default: @code{tun}) (type: dev)
30687 The device type used to represent the VPN connection.
30689 @item @code{ca} (default: @code{"/etc/openvpn/ca.crt"}) (type: maybe-string)
30690 The certificate authority to check connections against.
30692 @item @code{cert} (default: @code{"/etc/openvpn/client.crt"}) (type: maybe-string)
30693 The certificate of the machine the daemon is running on. It should be
30694 signed by the authority given in @code{ca}.
30696 @item @code{key} (default: @code{"/etc/openvpn/client.key"}) (type: maybe-string)
30697 The key of the machine the daemon is running on. It must be the key
30698 whose certificate is @code{cert}.
30700 @item @code{comp-lzo?} (default: @code{#t}) (type: boolean)
30701 Whether to use the lzo compression algorithm.
30703 @item @code{persist-key?} (default: @code{#t}) (type: boolean)
30704 Don't re-read key files across SIGUSR1 or --ping-restart.
30706 @item @code{persist-tun?} (default: @code{#t}) (type: boolean)
30707 Don't close and reopen TUN/TAP device or run up/down scripts across
30708 SIGUSR1 or --ping-restart restarts.
30710 @item @code{fast-io?} (default: @code{#f}) (type: boolean)
30711 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
30712 poll/epoll/select prior to the write operation.
30714 @item @code{verbosity} (default: @code{3}) (type: number)
30717 @item @code{tls-auth} (default: @code{#f}) (type: tls-auth-server)
30718 Add an additional layer of HMAC authentication on top of the TLS control
30719 channel to protect against DoS attacks.
30721 @item @code{port} (default: @code{1194}) (type: number)
30722 Specifies the port number on which the server listens.
30724 @item @code{server} (default: @code{"10.8.0.0 255.255.255.0"}) (type: ip-mask)
30725 An ip and mask specifying the subnet inside the virtual network.
30727 @item @code{server-ipv6} (default: @code{#f}) (type: cidr6)
30728 A CIDR notation specifying the IPv6 subnet inside the virtual network.
30730 @item @code{dh} (default: @code{"/etc/openvpn/dh2048.pem"}) (type: string)
30731 The Diffie-Hellman parameters file.
30733 @item @code{ifconfig-pool-persist} (default: @code{"/etc/openvpn/ipp.txt"}) (type: string)
30734 The file that records client IPs.
30736 @item @code{redirect-gateway?} (default: @code{#f}) (type: gateway)
30737 When true, the server will act as a gateway for its clients.
30739 @item @code{client-to-client?} (default: @code{#f}) (type: boolean)
30740 When true, clients are allowed to talk to each other inside the VPN.
30742 @item @code{keepalive} (default: @code{(10 120)}) (type: keepalive)
30743 Causes ping-like messages to be sent back and forth over the link so
30744 that each side knows when the other side has gone down. @code{keepalive}
30745 requires a pair. The first element is the period of the ping sending,
30746 and the second element is the timeout before considering the other side
30749 @item @code{max-clients} (default: @code{100}) (type: number)
30750 The maximum number of clients.
30752 @item @code{status} (default: @code{"/var/run/openvpn/status"}) (type: string)
30753 The status file. This file shows a small report on current connection.
30754 It is truncated and rewritten every minute.
30756 @item @code{client-config-dir} (default: @code{()}) (type: openvpn-ccd-list)
30757 The list of configuration for some clients.
30763 @c %end of automatic openvpn-server documentation
30765 @subheading strongSwan
30767 Currently, the strongSwan service only provides legacy-style configuration with
30768 @file{ipsec.conf} and @file{ipsec.secrets} files.
30770 @defvr {Scheme Variable} strongswan-service-type
30771 A service type for configuring strongSwan for IPsec @acronym{VPN,
30772 Virtual Private Networking}. Its value must be a
30773 @code{strongswan-configuration} record as in this example:
30776 (service strongswan-service-type
30777 (strongswan-configuration
30778 (ipsec-conf "/etc/ipsec.conf")
30779 (ipsec-secrets "/etc/ipsec.secrets")))
30784 @deftp {Data Type} strongswan-configuration
30785 Data type representing the configuration of the StrongSwan service.
30788 @item @code{strongswan}
30789 The strongSwan package to use for this service.
30791 @item @code{ipsec-conf} (default: @code{#f})
30792 The file name of your @file{ipsec.conf}. If not @code{#f}, then this and
30793 @code{ipsec-secrets} must both be strings.
30795 @item @code{ipsec-secrets} (default @code{#f})
30796 The file name of your @file{ipsec.secrets}. If not @code{#f}, then this and
30797 @code{ipsec-conf} must both be strings.
30802 @subsubheading Wireguard
30804 @defvr {Scheme Variable} wireguard-service-type
30805 A service type for a Wireguard tunnel interface. Its value must be a
30806 @code{wireguard-configuration} record as in this example:
30809 (service wireguard-service-type
30810 (wireguard-configuration
30815 (endpoint "my.wireguard.com:51820")
30816 (public-key "hzpKg9X1yqu1axN6iJp0mWf6BZGo8m1wteKwtTmDGF4=")
30817 (allowed-ips '("10.0.0.2/32")))))))
30822 @deftp {Data Type} wireguard-configuration
30823 Data type representing the configuration of the Wireguard service.
30826 @item @code{wireguard}
30827 The wireguard package to use for this service.
30829 @item @code{interface} (default: @code{"wg0"})
30830 The interface name for the VPN.
30832 @item @code{addresses} (default: @code{'("10.0.0.1/32")})
30833 The IP addresses to be assigned to the above interface.
30835 @item @code{port} (default: @code{51820})
30836 The port on which to listen for incoming connections.
30838 @item @code{dns} (default: @code{#f})
30839 The DNS server(s) to announce to VPN clients via DHCP.
30841 @item @code{private-key} (default: @code{"/etc/wireguard/private.key"})
30842 The private key file for the interface. It is automatically generated if
30843 the file does not exist.
30845 @item @code{peers} (default: @code{'()})
30846 The authorized peers on this interface. This is a list of
30847 @var{wireguard-peer} records.
30852 @deftp {Data Type} wireguard-peer
30853 Data type representing a Wireguard peer attached to a given interface.
30859 @item @code{endpoint} (default: @code{#f})
30860 The optional endpoint for the peer, such as
30861 @code{"demo.wireguard.com:51820"}.
30863 @item @code{public-key}
30864 The peer public-key represented as a base64 string.
30866 @item @code{allowed-ips}
30867 A list of IP addresses from which incoming traffic for this peer is
30868 allowed and to which incoming traffic for this peer is directed.
30870 @item @code{keep-alive} (default: @code{#f})
30871 An optional time interval in seconds. A packet will be sent to the
30872 server endpoint once per time interval. This helps receiving
30873 incoming connections from this peer when you are behind a NAT or
30879 @node Network File System
30880 @subsection Network File System
30883 The @code{(gnu services nfs)} module provides the following services,
30884 which are most commonly used in relation to mounting or exporting
30885 directory trees as @dfn{network file systems} (NFS).
30887 While it is possible to use the individual components that together make
30888 up a Network File System service, we recommended to configure an NFS
30889 server with the @code{nfs-service-type}.
30891 @subsubheading NFS Service
30892 @cindex NFS, server
30894 The NFS service takes care of setting up all NFS component services,
30895 kernel configuration file systems, and installs configuration files in
30896 the locations that NFS expects.
30898 @defvr {Scheme Variable} nfs-service-type
30899 A service type for a complete NFS server.
30902 @deftp {Data Type} nfs-configuration
30903 This data type represents the configuration of the NFS service and all
30906 It has the following parameters:
30908 @item @code{nfs-utils} (default: @code{nfs-utils})
30909 The nfs-utils package to use.
30911 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
30912 If a list of string values is provided, the @command{rpc.nfsd} daemon
30913 will be limited to supporting the given versions of the NFS protocol.
30915 @item @code{exports} (default: @code{'()})
30916 This is a list of directories the NFS server should export. Each entry
30917 is a list consisting of two elements: a directory name and a string
30918 containing all options. This is an example in which the directory
30919 @file{/export} is served to all NFS clients as a read-only share:
30925 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
30928 @item @code{rpcmountd-port} (default: @code{#f})
30929 The network port that the @command{rpc.mountd} daemon should use.
30931 @item @code{rpcstatd-port} (default: @code{#f})
30932 The network port that the @command{rpc.statd} daemon should use.
30934 @item @code{rpcbind} (default: @code{rpcbind})
30935 The rpcbind package to use.
30937 @item @code{idmap-domain} (default: @code{"localdomain"})
30938 The local NFSv4 domain name.
30940 @item @code{nfsd-port} (default: @code{2049})
30941 The network port that the @command{nfsd} daemon should use.
30943 @item @code{nfsd-threads} (default: @code{8})
30944 The number of threads used by the @command{nfsd} daemon.
30946 @item @code{nfsd-tcp?} (default: @code{#t})
30947 Whether the @command{nfsd} daemon should listen on a TCP socket.
30949 @item @code{nfsd-udp?} (default: @code{#f})
30950 Whether the @command{nfsd} daemon should listen on a UDP socket.
30952 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
30953 The directory where the pipefs file system is mounted.
30955 @item @code{debug} (default: @code{'()"})
30956 A list of subsystems for which debugging output should be enabled. This
30957 is a list of symbols. Any of these symbols are valid: @code{nfsd},
30958 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
30962 If you don't need a complete NFS service or prefer to build it yourself
30963 you can use the individual component services that are documented below.
30965 @subsubheading RPC Bind Service
30968 The RPC Bind service provides a facility to map program numbers into
30969 universal addresses.
30970 Many NFS related services use this facility. Hence it is automatically
30971 started when a dependent service starts.
30973 @defvr {Scheme Variable} rpcbind-service-type
30974 A service type for the RPC portmapper daemon.
30978 @deftp {Data Type} rpcbind-configuration
30979 Data type representing the configuration of the RPC Bind Service.
30980 This type has the following parameters:
30982 @item @code{rpcbind} (default: @code{rpcbind})
30983 The rpcbind package to use.
30985 @item @code{warm-start?} (default: @code{#t})
30986 If this parameter is @code{#t}, then the daemon will read a
30987 state file on startup thus reloading state information saved by a previous
30993 @subsubheading Pipefs Pseudo File System
30997 The pipefs file system is used to transfer NFS related data
30998 between the kernel and user space programs.
31000 @defvr {Scheme Variable} pipefs-service-type
31001 A service type for the pipefs pseudo file system.
31004 @deftp {Data Type} pipefs-configuration
31005 Data type representing the configuration of the pipefs pseudo file system service.
31006 This type has the following parameters:
31008 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31009 The directory to which the file system is to be attached.
31014 @subsubheading GSS Daemon Service
31017 @cindex global security system
31019 The @dfn{global security system} (GSS) daemon provides strong security for RPC
31021 Before exchanging RPC requests an RPC client must establish a security
31022 context. Typically this is done using the Kerberos command @command{kinit}
31023 or automatically at login time using PAM services (@pxref{Kerberos Services}).
31025 @defvr {Scheme Variable} gss-service-type
31026 A service type for the Global Security System (GSS) daemon.
31029 @deftp {Data Type} gss-configuration
31030 Data type representing the configuration of the GSS daemon service.
31031 This type has the following parameters:
31033 @item @code{nfs-utils} (default: @code{nfs-utils})
31034 The package in which the @command{rpc.gssd} command is to be found.
31036 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31037 The directory where the pipefs file system is mounted.
31043 @subsubheading IDMAP Daemon Service
31045 @cindex name mapper
31047 The idmap daemon service provides mapping between user IDs and user names.
31048 Typically it is required in order to access file systems mounted via NFSv4.
31050 @defvr {Scheme Variable} idmap-service-type
31051 A service type for the Identity Mapper (IDMAP) daemon.
31054 @deftp {Data Type} idmap-configuration
31055 Data type representing the configuration of the IDMAP daemon service.
31056 This type has the following parameters:
31058 @item @code{nfs-utils} (default: @code{nfs-utils})
31059 The package in which the @command{rpc.idmapd} command is to be found.
31061 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31062 The directory where the pipefs file system is mounted.
31064 @item @code{domain} (default: @code{#f})
31065 The local NFSv4 domain name.
31066 This must be a string or @code{#f}.
31067 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
31069 @item @code{verbosity} (default: @code{0})
31070 The verbosity level of the daemon.
31075 @node Continuous Integration
31076 @subsection Continuous Integration
31078 @cindex continuous integration
31079 @uref{https://guix.gnu.org/cuirass/, Cuirass} is a continuous
31080 integration tool for Guix. It can be used both for development and for
31081 providing substitutes to others (@pxref{Substitutes}).
31083 The @code{(gnu services cuirass)} module provides the following service.
31085 @defvr {Scheme Procedure} cuirass-service-type
31086 The type of the Cuirass service. Its value must be a
31087 @code{cuirass-configuration} object, as described below.
31090 To add build jobs, you have to set the @code{specifications} field of
31091 the configuration. For instance, the following example will build all
31092 the packages provided by the @code{my-channel} channel.
31095 (define %cuirass-specs
31096 #~(list (specification
31097 (name "my-channel")
31098 (build '(channels my-channel))
31102 (url "https://my-channel.git"))
31103 %default-channels)))))
31105 (service cuirass-service-type
31106 (cuirass-configuration
31107 (specifications %cuirass-specs)))
31110 To build the @code{linux-libre} package defined by the default Guix
31111 channel, one can use the following configuration.
31114 (define %cuirass-specs
31115 #~(list (specification
31117 (build '(packages "linux-libre")))))
31119 (service cuirass-service-type
31120 (cuirass-configuration
31121 (specifications %cuirass-specs)))
31124 The other configuration possibilities, as well as the specification
31125 record itself are described in the Cuirass manual
31126 (@pxref{Specifications,,, cuirass, Cuirass}).
31128 While information related to build jobs is located directly in the
31129 specifications, global settings for the @command{cuirass} process are
31130 accessible in other @code{cuirass-configuration} fields.
31132 @deftp {Data Type} cuirass-configuration
31133 Data type representing the configuration of Cuirass.
31136 @item @code{cuirass} (default: @code{cuirass})
31137 The Cuirass package to use.
31139 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
31140 Location of the log file.
31142 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
31143 Location of the log file used by the web interface.
31145 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
31146 Location of the repository cache.
31148 @item @code{user} (default: @code{"cuirass"})
31149 Owner of the @code{cuirass} process.
31151 @item @code{group} (default: @code{"cuirass"})
31152 Owner's group of the @code{cuirass} process.
31154 @item @code{interval} (default: @code{60})
31155 Number of seconds between the poll of the repositories followed by the
31158 @item @code{parameters} (default: @code{#f})
31159 Read parameters from the given @var{parameters} file. The supported
31160 parameters are described here (@pxref{Parameters,,, cuirass, Cuirass}).
31162 @item @code{remote-server} (default: @code{#f})
31163 A @code{cuirass-remote-server-configuration} record to use the build
31164 remote mechanism or @code{#f} to use the default build mechanism.
31166 @item @code{database} (default: @code{"dbname=cuirass host=/var/run/postgresql"})
31167 Use @var{database} as the database containing the jobs and the past
31168 build results. Since Cuirass uses PostgreSQL as a database engine,
31169 @var{database} must be a string such as @code{"dbname=cuirass
31172 @item @code{port} (default: @code{8081})
31173 Port number used by the HTTP server.
31175 @item @code{host} (default: @code{"localhost"})
31176 Listen on the network interface for @var{host}. The default is to
31177 accept connections from localhost.
31179 @item @code{specifications} (default: @code{#~'()})
31180 A gexp (@pxref{G-Expressions}) that evaluates to a list of
31181 specifications records. The specification record is described in the
31182 Cuirass manual (@pxref{Specifications,,, cuirass, Cuirass}).
31184 @item @code{use-substitutes?} (default: @code{#f})
31185 This allows using substitutes to avoid building every dependencies of a job
31188 @item @code{one-shot?} (default: @code{#f})
31189 Only evaluate specifications and build derivations once.
31191 @item @code{fallback?} (default: @code{#f})
31192 When substituting a pre-built binary fails, fall back to building
31195 @item @code{extra-options} (default: @code{'()})
31196 Extra options to pass when running the Cuirass processes.
31201 @cindex remote build
31202 @subsubheading Cuirass remote building
31204 Cuirass supports two mechanisms to build derivations.
31207 @item Using the local Guix daemon.
31208 This is the default build mechanism. Once the build jobs are
31209 evaluated, they are sent to the local Guix daemon. Cuirass then
31210 listens to the Guix daemon output to detect the various build events.
31212 @item Using the remote build mechanism.
31213 The build jobs are not submitted to the local Guix daemon. Instead, a
31214 remote server dispatches build requests to the connect remote workers,
31215 according to the build priorities.
31219 To enable this build mode a @code{cuirass-remote-server-configuration}
31220 record must be passed as @code{remote-server} argument of the
31221 @code{cuirass-configuration} record. The
31222 @code{cuirass-remote-server-configuration} record is described below.
31224 This build mode scales way better than the default build mode. This is
31225 the build mode that is used on the GNU Guix build farm at
31226 @url{https://ci.guix.gnu.org}. It should be preferred when using
31227 Cuirass to build large amount of packages.
31229 @deftp {Data Type} cuirass-remote-server-configuration
31230 Data type representing the configuration of the Cuirass remote-server.
31233 @item @code{backend-port} (default: @code{5555})
31234 The TCP port for communicating with @code{remote-worker} processes
31235 using ZMQ. It defaults to @code{5555}.
31237 @item @code{log-port} (default: @code{5556})
31238 The TCP port of the log server. It defaults to @code{5556}.
31240 @item @code{publish-port} (default: @code{5557})
31241 The TCP port of the publish server. It defaults to @code{5557}.
31243 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-server.log"})
31244 Location of the log file.
31246 @item @code{cache} (default: @code{"/var/cache/cuirass/remote"})
31247 Use @var{cache} directory to cache build log files.
31249 @item @code{trigger-url} (default: @code{#f})
31250 Once a substitute is successfully fetched, trigger substitute baking at
31253 @item @code{publish?} (default: @code{#t})
31254 If set to false, do not start a publish server and ignore the
31255 @code{publish-port} argument. This can be useful if there is already a
31256 standalone publish server standing next to the remote server.
31258 @item @code{public-key}
31259 @item @code{private-key}
31260 Use the specific @var{file}s as the public/private key pair used to sign
31261 the store items being published.
31266 At least one remote worker must also be started on any machine of the
31267 local network to actually perform the builds and report their status.
31269 @deftp {Data Type} cuirass-remote-worker-configuration
31270 Data type representing the configuration of the Cuirass remote-worker.
31273 @item @code{cuirass} (default: @code{cuirass})
31274 The Cuirass package to use.
31276 @item @code{workers} (default: @code{1})
31277 Start @var{workers} parallel workers.
31279 @item @code{server} (default: @code{#f})
31280 Do not use Avahi discovery and connect to the given @code{server} IP
31283 @item @code{systems} (default: @code{(list (%current-system))})
31284 Only request builds for the given @var{systems}.
31286 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-worker.log"})
31287 Location of the log file.
31289 @item @code{publish-port} (default: @code{5558})
31290 The TCP port of the publish server. It defaults to @code{5558}.
31292 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
31293 The list of URLs where to look for substitutes by default.
31295 @item @code{public-key}
31296 @item @code{private-key}
31297 Use the specific @var{file}s as the public/private key pair used to sign
31298 the store items being published.
31303 @subsubheading Laminar
31305 @uref{https://laminar.ohwg.net/, Laminar} is a lightweight and modular
31306 Continuous Integration service. It doesn't have a configuration web UI
31307 instead uses version-controllable configuration files and scripts.
31309 Laminar encourages the use of existing tools such as bash and cron
31310 instead of reinventing them.
31312 @defvr {Scheme Procedure} laminar-service-type
31313 The type of the Laminar service. Its value must be a
31314 @code{laminar-configuration} object, as described below.
31316 All configuration values have defaults, a minimal configuration to get
31317 Laminar running is shown below. By default, the web interface is
31318 available on port 8080.
31321 (service laminar-service-type)
31325 @deftp {Data Type} laminar-configuration
31326 Data type representing the configuration of Laminar.
31329 @item @code{laminar} (default: @code{laminar})
31330 The Laminar package to use.
31332 @item @code{home-directory} (default: @code{"/var/lib/laminar"})
31333 The directory for job configurations and run directories.
31335 @item @code{bind-http} (default: @code{"*:8080"})
31336 The interface/port or unix socket on which laminard should listen for
31337 incoming connections to the web frontend.
31339 @item @code{bind-rpc} (default: @code{"unix-abstract:laminar"})
31340 The interface/port or unix socket on which laminard should listen for
31341 incoming commands such as build triggers.
31343 @item @code{title} (default: @code{"Laminar"})
31344 The page title to show in the web frontend.
31346 @item @code{keep-rundirs} (default: @code{0})
31347 Set to an integer defining how many rundirs to keep per job. The
31348 lowest-numbered ones will be deleted. The default is 0, meaning all run
31349 dirs will be immediately deleted.
31351 @item @code{archive-url} (default: @code{#f})
31352 The web frontend served by laminard will use this URL to form links to
31353 artefacts archived jobs.
31355 @item @code{base-url} (default: @code{#f})
31356 Base URL to use for links to laminar itself.
31361 @node Power Management Services
31362 @subsection Power Management Services
31365 @cindex power management with TLP
31366 @subsubheading TLP daemon
31368 The @code{(gnu services pm)} module provides a Guix service definition
31369 for the Linux power management tool TLP.
31371 TLP enables various powersaving modes in userspace and kernel.
31372 Contrary to @code{upower-service}, it is not a passive,
31373 monitoring tool, as it will apply custom settings each time a new power
31374 source is detected. More information can be found at
31375 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
31377 @deffn {Scheme Variable} tlp-service-type
31378 The service type for the TLP tool. The default settings are optimised
31379 for battery life on most systems, but you can tweak them to your heart's
31380 content by adding a valid @code{tlp-configuration}:
31382 (service tlp-service-type
31384 (cpu-scaling-governor-on-ac (list "performance"))
31385 (sched-powersave-on-bat? #t)))
31389 Each parameter definition is preceded by its type; for example,
31390 @samp{boolean foo} indicates that the @code{foo} parameter should be
31391 specified as a boolean. Types starting with @code{maybe-} denote
31392 parameters that won't show up in TLP config file when their value is
31393 left unset, or is explicitly set to the @code{%unset-value} value.
31395 @c The following documentation was initially generated by
31396 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
31397 @c documentation is better, so we shouldn't hesitate to edit below as
31398 @c needed. However if the change you want to make to this documentation
31399 @c can be done in an automated way, it's probably easier to change
31400 @c (generate-documentation) than to make it below and have to deal with
31401 @c the churn as TLP updates.
31403 Available @code{tlp-configuration} fields are:
31405 @deftypevr {@code{tlp-configuration} parameter} package tlp
31410 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
31411 Set to true if you wish to enable TLP.
31413 Defaults to @samp{#t}.
31417 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
31418 Default mode when no power supply can be detected. Alternatives are AC
31421 Defaults to @samp{"AC"}.
31425 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
31426 Number of seconds Linux kernel has to wait after the disk goes idle,
31427 before syncing on AC.
31429 Defaults to @samp{0}.
31433 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
31434 Same as @code{disk-idle-ac} but on BAT mode.
31436 Defaults to @samp{2}.
31440 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
31441 Dirty pages flushing periodicity, expressed in seconds.
31443 Defaults to @samp{15}.
31447 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
31448 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
31450 Defaults to @samp{60}.
31454 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
31455 CPU frequency scaling governor on AC mode. With intel_pstate driver,
31456 alternatives are powersave and performance. With acpi-cpufreq driver,
31457 alternatives are ondemand, powersave, performance and conservative.
31459 Defaults to @samp{disabled}.
31463 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
31464 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
31466 Defaults to @samp{disabled}.
31470 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
31471 Set the min available frequency for the scaling governor on AC.
31473 Defaults to @samp{disabled}.
31477 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
31478 Set the max available frequency for the scaling governor on AC.
31480 Defaults to @samp{disabled}.
31484 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
31485 Set the min available frequency for the scaling governor on BAT.
31487 Defaults to @samp{disabled}.
31491 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
31492 Set the max available frequency for the scaling governor on BAT.
31494 Defaults to @samp{disabled}.
31498 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
31499 Limit the min P-state to control the power dissipation of the CPU, in AC
31500 mode. Values are stated as a percentage of the available performance.
31502 Defaults to @samp{disabled}.
31506 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
31507 Limit the max P-state to control the power dissipation of the CPU, in AC
31508 mode. Values are stated as a percentage of the available performance.
31510 Defaults to @samp{disabled}.
31514 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
31515 Same as @code{cpu-min-perf-on-ac} on BAT mode.
31517 Defaults to @samp{disabled}.
31521 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
31522 Same as @code{cpu-max-perf-on-ac} on BAT mode.
31524 Defaults to @samp{disabled}.
31528 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
31529 Enable CPU turbo boost feature on AC mode.
31531 Defaults to @samp{disabled}.
31535 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
31536 Same as @code{cpu-boost-on-ac?} on BAT mode.
31538 Defaults to @samp{disabled}.
31542 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
31543 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
31544 used under light load conditions.
31546 Defaults to @samp{#f}.
31550 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
31551 Same as @code{sched-powersave-on-ac?} but on BAT mode.
31553 Defaults to @samp{#t}.
31557 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
31558 Enable Linux kernel NMI watchdog.
31560 Defaults to @samp{#f}.
31564 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
31565 For Linux kernels with PHC patch applied, change CPU voltages. An
31566 example value would be @samp{"F:V F:V F:V F:V"}.
31568 Defaults to @samp{disabled}.
31572 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
31573 Set CPU performance versus energy saving policy on AC@. Alternatives are
31574 performance, normal, powersave.
31576 Defaults to @samp{"performance"}.
31580 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
31581 Same as @code{energy-perf-policy-ac} but on BAT mode.
31583 Defaults to @samp{"powersave"}.
31587 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
31592 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
31593 Hard disk advanced power management level.
31597 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
31598 Same as @code{disk-apm-bat} but on BAT mode.
31602 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
31603 Hard disk spin down timeout. One value has to be specified for each
31604 declared hard disk.
31606 Defaults to @samp{disabled}.
31610 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
31611 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
31613 Defaults to @samp{disabled}.
31617 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
31618 Select IO scheduler for disk devices. One value has to be specified for
31619 each declared hard disk. Example alternatives are cfq, deadline and
31622 Defaults to @samp{disabled}.
31626 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
31627 SATA aggressive link power management (ALPM) level. Alternatives are
31628 min_power, medium_power, max_performance.
31630 Defaults to @samp{"max_performance"}.
31634 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
31635 Same as @code{sata-linkpwr-ac} but on BAT mode.
31637 Defaults to @samp{"min_power"}.
31641 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
31642 Exclude specified SATA host devices for link power management.
31644 Defaults to @samp{disabled}.
31648 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
31649 Enable Runtime Power Management for AHCI controller and disks on AC
31652 Defaults to @samp{disabled}.
31656 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
31657 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
31659 Defaults to @samp{disabled}.
31663 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
31664 Seconds of inactivity before disk is suspended.
31666 Defaults to @samp{15}.
31670 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
31671 PCI Express Active State Power Management level. Alternatives are
31672 default, performance, powersave.
31674 Defaults to @samp{"performance"}.
31678 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
31679 Same as @code{pcie-aspm-ac} but on BAT mode.
31681 Defaults to @samp{"powersave"}.
31685 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat0
31686 Percentage when battery 0 should begin charging. Only supported on some laptops.
31688 Defaults to @samp{disabled}.
31692 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat0
31693 Percentage when battery 0 should stop charging. Only supported on some laptops.
31695 Defaults to @samp{disabled}.
31699 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat1
31700 Percentage when battery 1 should begin charging. Only supported on some laptops.
31702 Defaults to @samp{disabled}.
31706 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat1
31707 Percentage when battery 1 should stop charging. Only supported on some laptops.
31709 Defaults to @samp{disabled}.
31713 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
31714 Radeon graphics clock speed level. Alternatives are low, mid, high,
31717 Defaults to @samp{"high"}.
31721 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
31722 Same as @code{radeon-power-ac} but on BAT mode.
31724 Defaults to @samp{"low"}.
31728 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
31729 Radeon dynamic power management method (DPM). Alternatives are battery,
31732 Defaults to @samp{"performance"}.
31736 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
31737 Same as @code{radeon-dpm-state-ac} but on BAT mode.
31739 Defaults to @samp{"battery"}.
31743 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
31744 Radeon DPM performance level. Alternatives are auto, low, high.
31746 Defaults to @samp{"auto"}.
31750 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
31751 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
31753 Defaults to @samp{"auto"}.
31757 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
31758 Wifi power saving mode.
31760 Defaults to @samp{#f}.
31764 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
31765 Same as @code{wifi-power-ac?} but on BAT mode.
31767 Defaults to @samp{#t}.
31771 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
31772 Disable wake on LAN.
31774 Defaults to @samp{#t}.
31778 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
31779 Timeout duration in seconds before activating audio power saving on
31780 Intel HDA and AC97 devices. A value of 0 disables power saving.
31782 Defaults to @samp{0}.
31786 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
31787 Same as @code{sound-powersave-ac} but on BAT mode.
31789 Defaults to @samp{1}.
31793 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
31794 Disable controller in powersaving mode on Intel HDA devices.
31796 Defaults to @samp{#t}.
31800 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
31801 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
31802 powered on again by releasing (and reinserting) the eject lever or by
31803 pressing the disc eject button on newer models.
31805 Defaults to @samp{#f}.
31809 @deftypevr {@code{tlp-configuration} parameter} string bay-device
31810 Name of the optical drive device to power off.
31812 Defaults to @samp{"sr0"}.
31816 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
31817 Runtime Power Management for PCI(e) bus devices. Alternatives are on
31820 Defaults to @samp{"on"}.
31824 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
31825 Same as @code{runtime-pm-ac} but on BAT mode.
31827 Defaults to @samp{"auto"}.
31831 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
31832 Runtime Power Management for all PCI(e) bus devices, except blacklisted
31835 Defaults to @samp{#t}.
31839 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
31840 Exclude specified PCI(e) device addresses from Runtime Power Management.
31842 Defaults to @samp{disabled}.
31846 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
31847 Exclude PCI(e) devices assigned to the specified drivers from Runtime
31852 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
31853 Enable USB autosuspend feature.
31855 Defaults to @samp{#t}.
31859 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
31860 Exclude specified devices from USB autosuspend.
31862 Defaults to @samp{disabled}.
31866 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
31867 Exclude WWAN devices from USB autosuspend.
31869 Defaults to @samp{#t}.
31873 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
31874 Include specified devices into USB autosuspend, even if they are already
31875 excluded by the driver or via @code{usb-blacklist-wwan?}.
31877 Defaults to @samp{disabled}.
31881 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
31882 Enable USB autosuspend before shutdown.
31884 Defaults to @samp{disabled}.
31888 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
31889 Restore radio device state (bluetooth, wifi, wwan) from previous
31890 shutdown on system startup.
31892 Defaults to @samp{#f}.
31897 @cindex CPU frequency scaling with thermald
31898 @subsubheading Thermald daemon
31900 The @code{(gnu services pm)} module provides an interface to
31901 thermald, a CPU frequency scaling service which helps prevent overheating.
31903 @defvr {Scheme Variable} thermald-service-type
31904 This is the service type for
31905 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
31906 Thermal Daemon, which is responsible for controlling the thermal state
31907 of processors and preventing overheating.
31910 @deftp {Data Type} thermald-configuration
31911 Data type representing the configuration of @code{thermald-service-type}.
31914 @item @code{adaptive?} (default: @code{#f})
31915 Use @acronym{DPTF, Dynamic Power and Thermal Framework} adaptive tables
31918 @item @code{ignore-cpuid-check?} (default: @code{#f})
31919 Ignore cpuid check for supported CPU models.
31921 @item @code{thermald} (default: @var{thermald})
31922 Package object of thermald.
31927 @node Audio Services
31928 @subsection Audio Services
31930 The @code{(gnu services audio)} module provides a service to start MPD
31931 (the Music Player Daemon).
31934 @subsubheading Music Player Daemon
31936 The Music Player Daemon (MPD) is a service that can play music while
31937 being controlled from the local machine or over the network by a variety
31940 The following example shows how one might run @code{mpd} as user
31941 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
31944 (service mpd-service-type
31950 @defvr {Scheme Variable} mpd-service-type
31951 The service type for @command{mpd}
31954 @deftp {Data Type} mpd-configuration
31955 Data type representing the configuration of @command{mpd}.
31958 @item @code{user} (default: @code{"mpd"})
31959 The user to run mpd as.
31961 @item @code{music-dir} (default: @code{"~/Music"})
31962 The directory to scan for music files.
31964 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
31965 The directory to store playlists.
31967 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
31968 The location of the music database.
31970 @item @code{state-file} (default: @code{"~/.mpd/state"})
31971 The location of the file that stores current MPD's state.
31973 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
31974 The location of the sticker database.
31976 @item @code{port} (default: @code{"6600"})
31977 The port to run mpd on.
31979 @item @code{address} (default: @code{"any"})
31980 The address that mpd will bind to. To use a Unix domain socket,
31981 an absolute path can be specified here.
31983 @item @code{outputs} (default: @code{"(list (mpd-output))"})
31984 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
31989 @deftp {Data Type} mpd-output
31990 Data type representing an @command{mpd} audio output.
31993 @item @code{name} (default: @code{"MPD"})
31994 The name of the audio output.
31996 @item @code{type} (default: @code{"pulse"})
31997 The type of audio output.
31999 @item @code{enabled?} (default: @code{#t})
32000 Specifies whether this audio output is enabled when MPD is started. By
32001 default, all audio outputs are enabled. This is just the default
32002 setting when there is no state file; with a state file, the previous
32005 @item @code{tags?} (default: @code{#t})
32006 If set to @code{#f}, then MPD will not send tags to this output. This
32007 is only useful for output plugins that can receive tags, for example the
32008 @code{httpd} output plugin.
32010 @item @code{always-on?} (default: @code{#f})
32011 If set to @code{#t}, then MPD attempts to keep this audio output always
32012 open. This may be useful for streaming servers, when you don’t want to
32013 disconnect all listeners even when playback is accidentally stopped.
32015 @item @code{mixer-type}
32016 This field accepts a symbol that specifies which mixer should be used
32017 for this audio output: the @code{hardware} mixer, the @code{software}
32018 mixer, the @code{null} mixer (allows setting the volume, but with no
32019 effect; this can be used as a trick to implement an external mixer
32020 External Mixer) or no mixer (@code{none}).
32022 @item @code{extra-options} (default: @code{'()})
32023 An association list of option symbols to string values to be appended to
32024 the audio output configuration.
32029 The following example shows a configuration of @code{mpd} that provides
32030 an HTTP audio streaming output.
32033 (service mpd-service-type
32041 `((encoder . "vorbis")
32042 (port . "8080"))))))))
32046 @node Virtualization Services
32047 @subsection Virtualization Services
32049 The @code{(gnu services virtualization)} module provides services for
32050 the libvirt and virtlog daemons, as well as other virtualization-related
32053 @subsubheading Libvirt daemon
32055 @code{libvirtd} is the server side daemon component of the libvirt
32056 virtualization management system. This daemon runs on host servers
32057 and performs required management tasks for virtualized guests.
32059 @deffn {Scheme Variable} libvirt-service-type
32060 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
32061 Its value must be a @code{libvirt-configuration}.
32064 (service libvirt-service-type
32065 (libvirt-configuration
32066 (unix-sock-group "libvirt")
32067 (tls-port "16555")))
32071 @c Auto-generated with (generate-libvirt-documentation)
32072 Available @code{libvirt-configuration} fields are:
32074 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
32079 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
32080 Flag listening for secure TLS connections on the public TCP/IP port.
32081 You must set @code{listen} for this to have any effect.
32083 It is necessary to setup a CA and issue server certificates before using
32086 Defaults to @samp{#t}.
32090 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
32091 Listen for unencrypted TCP connections on the public TCP/IP port. You must
32092 set @code{listen} for this to have any effect.
32094 Using the TCP socket requires SASL authentication by default. Only SASL
32095 mechanisms which support data encryption are allowed. This is
32096 DIGEST_MD5 and GSSAPI (Kerberos5).
32098 Defaults to @samp{#f}.
32102 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
32103 Port for accepting secure TLS connections. This can be a port number,
32106 Defaults to @samp{"16514"}.
32110 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
32111 Port for accepting insecure TCP connections. This can be a port number,
32114 Defaults to @samp{"16509"}.
32118 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
32119 IP address or hostname used for client connections.
32121 Defaults to @samp{"0.0.0.0"}.
32125 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
32126 Flag toggling mDNS advertisement of the libvirt service.
32128 Alternatively can disable for all services on a host by stopping the
32131 Defaults to @samp{#f}.
32135 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
32136 Default mDNS advertisement name. This must be unique on the immediate
32139 Defaults to @samp{"Virtualization Host <hostname>"}.
32143 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
32144 UNIX domain socket group ownership. This can be used to allow a
32145 'trusted' set of users access to management capabilities without
32148 Defaults to @samp{"root"}.
32152 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
32153 UNIX socket permissions for the R/O socket. This is used for monitoring
32156 Defaults to @samp{"0777"}.
32160 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
32161 UNIX socket permissions for the R/W socket. Default allows only root.
32162 If PolicyKit is enabled on the socket, the default will change to allow
32163 everyone (eg, 0777)
32165 Defaults to @samp{"0770"}.
32169 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
32170 UNIX socket permissions for the admin socket. Default allows only owner
32171 (root), do not change it unless you are sure to whom you are exposing
32174 Defaults to @samp{"0777"}.
32178 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
32179 The directory in which sockets will be found/created.
32181 Defaults to @samp{"/var/run/libvirt"}.
32185 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
32186 Authentication scheme for UNIX read-only sockets. By default socket
32187 permissions allow anyone to connect
32189 Defaults to @samp{"polkit"}.
32193 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
32194 Authentication scheme for UNIX read-write sockets. By default socket
32195 permissions only allow root. If PolicyKit support was compiled into
32196 libvirt, the default will be to use 'polkit' auth.
32198 Defaults to @samp{"polkit"}.
32202 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
32203 Authentication scheme for TCP sockets. If you don't enable SASL, then
32204 all TCP traffic is cleartext. Don't do this outside of a dev/test
32207 Defaults to @samp{"sasl"}.
32211 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
32212 Authentication scheme for TLS sockets. TLS sockets already have
32213 encryption provided by the TLS layer, and limited authentication is done
32216 It is possible to make use of any SASL authentication mechanism as well,
32217 by using 'sasl' for this option
32219 Defaults to @samp{"none"}.
32223 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
32224 API access control scheme.
32226 By default an authenticated user is allowed access to all APIs. Access
32227 drivers can place restrictions on this.
32229 Defaults to @samp{()}.
32233 @deftypevr {@code{libvirt-configuration} parameter} string key-file
32234 Server key file path. If set to an empty string, then no private key is
32237 Defaults to @samp{""}.
32241 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
32242 Server key file path. If set to an empty string, then no certificate is
32245 Defaults to @samp{""}.
32249 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
32250 Server key file path. If set to an empty string, then no CA certificate
32253 Defaults to @samp{""}.
32257 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
32258 Certificate revocation list path. If set to an empty string, then no
32261 Defaults to @samp{""}.
32265 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
32266 Disable verification of our own server certificates.
32268 When libvirtd starts it performs some sanity checks against its own
32271 Defaults to @samp{#f}.
32275 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
32276 Disable verification of client certificates.
32278 Client certificate verification is the primary authentication mechanism.
32279 Any client which does not present a certificate signed by the CA will be
32282 Defaults to @samp{#f}.
32286 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
32287 Whitelist of allowed x509 Distinguished Name.
32289 Defaults to @samp{()}.
32293 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
32294 Whitelist of allowed SASL usernames. The format for username depends on
32295 the SASL authentication mechanism.
32297 Defaults to @samp{()}.
32301 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
32302 Override the compile time default TLS priority string. The default is
32303 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
32304 is desired for libvirt to deviate from the global default settings.
32306 Defaults to @samp{"NORMAL"}.
32310 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
32311 Maximum number of concurrent client connections to allow over all
32314 Defaults to @samp{5000}.
32318 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
32319 Maximum length of queue of connections waiting to be accepted by the
32320 daemon. Note, that some protocols supporting retransmission may obey
32321 this so that a later reattempt at connection succeeds.
32323 Defaults to @samp{1000}.
32327 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
32328 Maximum length of queue of accepted but not yet authenticated clients.
32329 Set this to zero to turn this feature off
32331 Defaults to @samp{20}.
32335 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
32336 Number of workers to start up initially.
32338 Defaults to @samp{5}.
32342 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
32343 Maximum number of worker threads.
32345 If the number of active clients exceeds @code{min-workers}, then more
32346 threads are spawned, up to max_workers limit. Typically you'd want
32347 max_workers to equal maximum number of clients allowed.
32349 Defaults to @samp{20}.
32353 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
32354 Number of priority workers. If all workers from above pool are stuck,
32355 some calls marked as high priority (notably domainDestroy) can be
32356 executed in this pool.
32358 Defaults to @samp{5}.
32362 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
32363 Total global limit on concurrent RPC calls.
32365 Defaults to @samp{20}.
32369 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
32370 Limit on concurrent requests from a single client connection. To avoid
32371 one client monopolizing the server this should be a small fraction of
32372 the global max_requests and max_workers parameter.
32374 Defaults to @samp{5}.
32378 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
32379 Same as @code{min-workers} but for the admin interface.
32381 Defaults to @samp{1}.
32385 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
32386 Same as @code{max-workers} but for the admin interface.
32388 Defaults to @samp{5}.
32392 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
32393 Same as @code{max-clients} but for the admin interface.
32395 Defaults to @samp{5}.
32399 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
32400 Same as @code{max-queued-clients} but for the admin interface.
32402 Defaults to @samp{5}.
32406 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
32407 Same as @code{max-client-requests} but for the admin interface.
32409 Defaults to @samp{5}.
32413 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
32414 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
32416 Defaults to @samp{3}.
32420 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
32423 A filter allows to select a different logging level for a given category
32424 of logs. The format for a filter is one of:
32435 where @code{name} is a string which is matched against the category
32436 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
32437 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
32438 name in the filter can be a substring of the full category name, in
32439 order to match multiple similar categories), the optional @samp{"+"}
32440 prefix tells libvirt to log stack trace for each message matching name,
32441 and @code{x} is the minimal level where matching messages should be
32459 Multiple filters can be defined in a single filters statement, they just
32460 need to be separated by spaces.
32462 Defaults to @samp{"3:remote 4:event"}.
32466 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
32469 An output is one of the places to save logging information. The format
32470 for an output can be:
32474 output goes to stderr
32476 @item x:syslog:name
32477 use syslog for the output and use the given name as the ident
32479 @item x:file:file_path
32480 output to a file, with the given filepath
32483 output to journald logging system
32487 In all case the x prefix is the minimal level, acting as a filter
32504 Multiple outputs can be defined, they just need to be separated by
32507 Defaults to @samp{"3:stderr"}.
32511 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
32512 Allows usage of the auditing subsystem to be altered
32516 0: disable all auditing
32519 1: enable auditing, only if enabled on host
32522 2: enable auditing, and exit if disabled on host.
32526 Defaults to @samp{1}.
32530 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
32531 Send audit messages via libvirt logging infrastructure.
32533 Defaults to @samp{#f}.
32537 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
32538 Host UUID@. UUID must not have all digits be the same.
32540 Defaults to @samp{""}.
32544 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
32545 Source to read host UUID.
32549 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
32552 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
32556 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
32559 Defaults to @samp{"smbios"}.
32563 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
32564 A keepalive message is sent to a client after @code{keepalive_interval}
32565 seconds of inactivity to check if the client is still responding. If
32566 set to -1, libvirtd will never send keepalive requests; however clients
32567 can still send them and the daemon will send responses.
32569 Defaults to @samp{5}.
32573 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
32574 Maximum number of keepalive messages that are allowed to be sent to the
32575 client without getting any response before the connection is considered
32578 In other words, the connection is automatically closed approximately
32579 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
32580 the last message received from the client. When @code{keepalive-count}
32581 is set to 0, connections will be automatically closed after
32582 @code{keepalive-interval} seconds of inactivity without sending any
32583 keepalive messages.
32585 Defaults to @samp{5}.
32589 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
32590 Same as above but for admin interface.
32592 Defaults to @samp{5}.
32596 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
32597 Same as above but for admin interface.
32599 Defaults to @samp{5}.
32603 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
32604 Timeout for Open vSwitch calls.
32606 The @code{ovs-vsctl} utility is used for the configuration and its
32607 timeout option is set by default to 5 seconds to avoid potential
32608 infinite waits blocking libvirt.
32610 Defaults to @samp{5}.
32614 @c %end of autogenerated docs
32616 @subsubheading Virtlog daemon
32617 The virtlogd service is a server side daemon component of libvirt that is
32618 used to manage logs from virtual machine consoles.
32620 This daemon is not used directly by libvirt client applications, rather it
32621 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
32622 standalone daemon, the main @code{libvirtd} daemon can be restarted without
32623 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
32624 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
32626 @deffn {Scheme Variable} virtlog-service-type
32627 This is the type of the virtlog daemon.
32628 Its value must be a @code{virtlog-configuration}.
32631 (service virtlog-service-type
32632 (virtlog-configuration
32633 (max-clients 1000)))
32637 @deftypevar {@code{libvirt} parameter} package libvirt
32641 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
32642 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
32644 Defaults to @samp{3}.
32648 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
32651 A filter allows to select a different logging level for a given category
32652 of logs The format for a filter is one of:
32663 where @code{name} is a string which is matched against the category
32664 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
32665 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
32666 be a substring of the full category name, in order to match multiple
32667 similar categories), the optional "+" prefix tells libvirt to log stack
32668 trace for each message matching name, and @code{x} is the minimal level
32669 where matching messages should be logged:
32686 Multiple filters can be defined in a single filters statement, they just
32687 need to be separated by spaces.
32689 Defaults to @samp{"3:remote 4:event"}.
32693 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
32696 An output is one of the places to save logging information The format
32697 for an output can be:
32701 output goes to stderr
32703 @item x:syslog:name
32704 use syslog for the output and use the given name as the ident
32706 @item x:file:file_path
32707 output to a file, with the given filepath
32710 output to journald logging system
32714 In all case the x prefix is the minimal level, acting as a filter
32731 Multiple outputs can be defined, they just need to be separated by
32734 Defaults to @samp{"3:stderr"}.
32738 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
32739 Maximum number of concurrent client connections to allow over all
32742 Defaults to @samp{1024}.
32746 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
32747 Maximum file size before rolling over.
32749 Defaults to @samp{2MB}
32753 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
32754 Maximum number of backup files to keep.
32756 Defaults to @samp{3}
32760 @anchor{transparent-emulation-qemu}
32761 @subsubheading Transparent Emulation with QEMU
32764 @cindex @code{binfmt_misc}
32765 @code{qemu-binfmt-service-type} provides support for transparent
32766 emulation of program binaries built for different architectures---e.g.,
32767 it allows you to transparently execute an ARMv7 program on an x86_64
32768 machine. It achieves this by combining the @uref{https://www.qemu.org,
32769 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
32770 This feature only allows you to emulate GNU/Linux on a different
32771 architecture, but see below for GNU/Hurd support.
32773 @defvr {Scheme Variable} qemu-binfmt-service-type
32774 This is the type of the QEMU/binfmt service for transparent emulation.
32775 Its value must be a @code{qemu-binfmt-configuration} object, which
32776 specifies the QEMU package to use as well as the architecture we want to
32780 (service qemu-binfmt-service-type
32781 (qemu-binfmt-configuration
32782 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
32785 In this example, we enable transparent emulation for the ARM and aarch64
32786 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
32787 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
32788 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
32791 @deftp {Data Type} qemu-binfmt-configuration
32792 This is the configuration for the @code{qemu-binfmt} service.
32795 @item @code{platforms} (default: @code{'()})
32796 The list of emulated QEMU platforms. Each item must be a @dfn{platform
32797 object} as returned by @code{lookup-qemu-platforms} (see below).
32799 For example, let's suppose you're on an x86_64 machine and you have this
32803 (service qemu-binfmt-service-type
32804 (qemu-binfmt-configuration
32805 (platforms (lookup-qemu-platforms "arm"))))
32811 guix build -s armhf-linux inkscape
32815 and it will build Inkscape for ARMv7 @emph{as if it were a native
32816 build}, transparently using QEMU to emulate the ARMv7 CPU@. Pretty handy
32817 if you'd like to test a package build for an architecture you don't have
32820 @item @code{qemu} (default: @code{qemu})
32821 The QEMU package to use.
32825 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
32826 Return the list of QEMU platform objects corresponding to
32827 @var{platforms}@dots{}. @var{platforms} must be a list of strings
32828 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
32829 @code{"mips64el"}, and so on.
32832 @deffn {Scheme Procedure} qemu-platform? @var{obj}
32833 Return true if @var{obj} is a platform object.
32836 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
32837 Return the name of @var{platform}---a string such as @code{"arm"}.
32841 @subsubheading QEMU Guest Agent
32845 The QEMU guest agent provides control over the emulated system to the
32846 host. The @code{qemu-guest-agent} service runs the agent on Guix
32847 guests. To control the agent from the host, open a socket by invoking
32848 QEMU with the following arguments:
32851 qemu-system-x86_64 \
32852 -chardev socket,path=/tmp/qga.sock,server=on,wait=off,id=qga0 \
32853 -device virtio-serial \
32854 -device virtserialport,chardev=qga0,name=org.qemu.guest_agent.0 \
32858 This creates a socket at @file{/tmp/qga.sock} on the host. Once the
32859 guest agent is running, you can issue commands with @code{socat}:
32862 $ guix shell socat -- socat unix-connect:/tmp/qga.sock stdio
32863 @{"execute": "guest-get-host-name"@}
32864 @{"return": @{"host-name": "guix"@}@}
32867 See @url{https://wiki.qemu.org/Features/GuestAgent,QEMU guest agent
32868 documentation} for more options and commands.
32870 @defvr {Scheme Variable} qemu-guest-agent-service-type
32871 Service type for the QEMU guest agent service.
32874 @deftp {Data Type} qemu-guest-agent-configuration
32875 Configuration for the @code{qemu-guest-agent} service.
32878 @item @code{qemu} (default: @code{qemu-minimal})
32879 The QEMU package to use.
32881 @item @code{device} (default: @code{""})
32882 File name of the device or socket the agent uses to communicate with the
32883 host. If empty, QEMU uses a default file name.
32888 @subsubheading The Hurd in a Virtual Machine
32890 @cindex @code{hurd}
32894 Service @code{hurd-vm} provides support for running GNU/Hurd in a
32895 virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
32896 to be used on GNU/Linux and the given GNU/Hurd operating system
32897 configuration is cross-compiled. The virtual machine is a Shepherd
32898 service that can be referred to by the names @code{hurd-vm} and
32899 @code{childhurd} and be controlled with commands such as:
32903 herd stop childhurd
32906 When the service is running, you can view its console by connecting to
32907 it with a VNC client, for example with:
32910 guix shell tigervnc-client -- vncviewer localhost:5900
32913 The default configuration (see @code{hurd-vm-configuration} below)
32914 spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
32915 (the virtual machine emulator) redirects to port 10222 on the host.
32916 Thus, you can connect over SSH to the childhurd with:
32919 ssh root@@localhost -p 10022
32922 The childhurd is volatile and stateless: it starts with a fresh root
32923 file system every time you restart it. By default though, all the files
32924 under @file{/etc/childhurd} on the host are copied as is to the root
32925 file system of the childhurd when it boots. This allows you to
32926 initialize ``secrets'' inside the VM: SSH host keys, authorized
32927 substitute keys, and so on---see the explanation of @code{secret-root}
32930 @defvr {Scheme Variable} hurd-vm-service-type
32931 This is the type of the Hurd in a Virtual Machine service. Its value
32932 must be a @code{hurd-vm-configuration} object, which specifies the
32933 operating system (@pxref{operating-system Reference}) and the disk size
32934 for the Hurd Virtual Machine, the QEMU package to use as well as the
32935 options for running it.
32940 (service hurd-vm-service-type
32941 (hurd-vm-configuration
32942 (disk-size (* 5000 (expt 2 20))) ;5G
32943 (memory-size 1024))) ;1024MiB
32946 would create a disk image big enough to build GNU@tie{}Hello, with some
32950 @deftp {Data Type} hurd-vm-configuration
32951 The data type representing the configuration for
32952 @code{hurd-vm-service-type}.
32955 @item @code{os} (default: @var{%hurd-vm-operating-system})
32956 The operating system to instantiate. This default is bare-bones with a
32957 permissive OpenSSH secure shell daemon listening on port 2222
32958 (@pxref{Networking Services, @code{openssh-service-type}}).
32960 @item @code{qemu} (default: @code{qemu-minimal})
32961 The QEMU package to use.
32963 @item @code{image} (default: @var{hurd-vm-disk-image})
32964 The procedure used to build the disk-image built from this
32967 @item @code{disk-size} (default: @code{'guess})
32968 The size of the disk image.
32970 @item @code{memory-size} (default: @code{512})
32971 The memory size of the Virtual Machine in mebibytes.
32973 @item @code{options} (default: @code{'("--snapshot")})
32974 The extra options for running QEMU.
32976 @item @code{id} (default: @code{#f})
32977 If set, a non-zero positive integer used to parameterize Childhurd
32978 instances. It is appended to the service's name,
32979 e.g. @code{childhurd1}.
32981 @item @code{net-options} (default: @var{hurd-vm-net-options})
32982 The procedure used to produce the list of QEMU networking options.
32984 By default, it produces
32987 '("--device" "rtl8139,netdev=net0"
32988 "--netdev" (string-append
32990 "hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004,"
32991 "hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222,"
32992 "hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900"))
32995 with forwarded ports:
32998 @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
32999 @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
33000 @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
33003 @item @code{secret-root} (default: @file{/etc/childhurd})
33004 The root directory with out-of-band secrets to be installed into the
33005 childhurd once it runs. Childhurds are volatile which means that on
33006 every startup, secrets such as the SSH host keys and Guix signing key
33009 If the @file{/etc/childhurd} directory does not exist, the
33010 @code{secret-service} running in the Childhurd will be sent an empty
33013 By default, the service automatically populates @file{/etc/childhurd}
33014 with the following non-volatile secrets, unless they already exist:
33017 /etc/childhurd/etc/guix/acl
33018 /etc/childhurd/etc/guix/signing-key.pub
33019 /etc/childhurd/etc/guix/signing-key.sec
33020 /etc/childhurd/etc/ssh/ssh_host_ed25519_key
33021 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
33022 /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
33023 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
33026 These files are automatically sent to the guest Hurd VM when it boots,
33027 including permissions.
33029 @cindex childhurd, offloading
33030 @cindex Hurd, offloading
33031 Having these files in place means that only a couple of things are
33032 missing to allow the host to offload @code{i586-gnu} builds to the
33037 Authorizing the childhurd's key on the host so that the host accepts
33038 build results coming from the childhurd, which can be done like so:
33041 guix archive --authorize < \
33042 /etc/childhurd/etc/guix/signing-key.pub
33046 Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
33050 We're working towards making that happen automatically---get in touch
33051 with us at @email{guix-devel@@gnu.org} to discuss it!
33055 Note that by default the VM image is volatile, i.e., once stopped the
33056 contents are lost. If you want a stateful image instead, override the
33057 configuration's @code{image} and @code{options} without
33058 the @code{--snapshot} flag using something along these lines:
33061 (service hurd-vm-service-type
33062 (hurd-vm-configuration
33063 (image (const "/out/of/store/writable/hurd.img"))
33067 @subsubheading Ganeti
33072 This service is considered experimental. Configuration options may be changed
33073 in a backwards-incompatible manner, and not all features have been thorougly
33074 tested. Users of this service are encouraged to share their experience at
33075 @email{guix-devel@@gnu.org}.
33078 Ganeti is a virtual machine management system. It is designed to keep virtual
33079 machines running on a cluster of servers even in the event of hardware failures,
33080 and to make maintenance and recovery tasks easy. It consists of multiple
33081 services which are described later in this section. In addition to the Ganeti
33082 service, you will need the OpenSSH service (@pxref{Networking Services,
33083 @code{openssh-service-type}}), and update the @file{/etc/hosts} file
33084 (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
33085 and address (or use a DNS server).
33087 All nodes participating in a Ganeti cluster should have the same Ganeti and
33088 @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
33089 cluster node that supports multiple storage backends, and installs the
33090 @code{debootstrap} and @code{guix} @dfn{OS providers}:
33093 (use-package-modules virtualization)
33094 (use-service-modules base ganeti networking ssh)
33097 (host-name "node1")
33098 (hosts-file (plain-file "hosts" (format #f "
33099 127.0.0.1 localhost
33102 192.168.1.200 ganeti.example.com
33103 192.168.1.201 node1.example.com node1
33104 192.168.1.202 node2.example.com node2
33107 ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
33108 ;; in order to use the "plain", "drbd" and "rbd" storage backends.
33109 (packages (append (map specification->package
33110 '("qemu" "lvm2" "drbd-utils" "ceph"
33111 ;; Add the debootstrap and guix OS providers.
33112 "ganeti-instance-guix" "ganeti-instance-debootstrap"))
33115 (append (list (service static-networking-service-type
33116 (list (static-networking
33118 (list (network-address
33120 (value "192.168.1.201/24"))))
33122 (list (network-route
33123 (destination "default")
33124 (gateway "192.168.1.254"))))
33125 (name-servers '("192.168.1.252"
33126 "192.168.1.253")))))
33128 ;; Ganeti uses SSH to communicate between nodes.
33129 (service openssh-service-type
33130 (openssh-configuration
33131 (permit-root-login 'prohibit-password)))
33133 (service ganeti-service-type
33134 (ganeti-configuration
33135 ;; This list specifies allowed file system paths
33136 ;; for storing virtual machine images.
33137 (file-storage-paths '("/srv/ganeti/file-storage"))
33138 ;; This variable configures a single "variant" for
33139 ;; both Debootstrap and Guix that works with KVM.
33140 (os %default-ganeti-os))))
33144 Users are advised to read the
33145 @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
33146 administrators guide} to learn about the various cluster options and
33147 day-to-day operations. There is also a
33148 @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
33149 describing how to configure and initialize a small cluster.
33151 @defvr {Scheme Variable} ganeti-service-type
33152 This is a service type that includes all the various services that Ganeti
33155 Its value is a @code{ganeti-configuration} object that defines the package
33156 to use for CLI operations, as well as configuration for the various daemons.
33157 Allowed file storage paths and available guest operating systems are also
33158 configured through this data type.
33161 @deftp {Data Type} ganeti-configuration
33162 The @code{ganeti} service takes the following configuration options:
33165 @item @code{ganeti} (default: @code{ganeti})
33166 The @code{ganeti} package to use. It will be installed to the system profile
33167 and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
33168 that the value specified here does not affect the other services as each refer
33169 to a specific @code{ganeti} package (see below).
33171 @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
33172 @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
33173 @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
33174 @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
33175 @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
33176 @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
33177 @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
33178 @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
33179 @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
33180 @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
33182 These options control the various daemons and cron jobs that are distributed
33183 with Ganeti. The possible values for these are described in detail below.
33184 To override a setting, you must use the configuration type for that service:
33187 (service ganeti-service-type
33188 (ganeti-configuration
33189 (rapi-configuration
33190 (ganeti-rapi-configuration
33191 (interface "eth1"))))
33192 (watcher-configuration
33193 (ganeti-watcher-configuration
33194 (rapi-ip "10.0.0.1"))))
33197 @item @code{file-storage-paths} (default: @code{'()})
33198 List of allowed directories for file storage backend.
33200 @item @code{os} (default: @code{%default-ganeti-os})
33201 List of @code{<ganeti-os>} records.
33204 In essence @code{ganeti-service-type} is shorthand for declaring each service
33208 (service ganeti-noded-service-type)
33209 (service ganeti-confd-service-type)
33210 (service ganeti-wconfd-service-type)
33211 (service ganeti-luxid-service-type)
33212 (service ganeti-kvmd-service-type)
33213 (service ganeti-mond-service-type)
33214 (service ganeti-metad-service-type)
33215 (service ganeti-watcher-service-type)
33216 (service ganeti-cleaner-service-type)
33219 Plus a service extension for @code{etc-service-type} that configures the file
33220 storage backend and OS variants.
33224 @deftp {Data Type} ganeti-os
33225 This data type is suitable for passing to the @code{os} parameter of
33226 @code{ganeti-configuration}. It takes the following parameters:
33230 The name for this OS provider. It is only used to specify where the
33231 configuration ends up. Setting it to ``debootstrap'' will create
33232 @file{/etc/ganeti/instance-debootstrap}.
33234 @item @code{extension}
33235 The file extension for variants of this OS type. For example
33236 @file{.conf} or @file{.scm}.
33238 @item @code{variants} (default: @code{'()})
33239 List of @code{ganeti-os-variant} objects for this OS.
33244 @deftp {Data Type} ganeti-os-variant
33245 This is the data type for a Ganeti OS variant. It takes the following
33250 The name of this variant.
33252 @item @code{configuration}
33253 A configuration file for this variant.
33257 @defvr {Scheme Variable} %default-debootstrap-hooks
33258 This variable contains hooks to configure networking and the GRUB bootloader.
33261 @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
33262 This variable contains a list of packages suitable for a fully-virtualized guest.
33265 @deftp {Data Type} debootstrap-configuration
33267 This data type creates configuration files suitable for the debootstrap OS provider.
33270 @item @code{hooks} (default: @code{%default-debootstrap-hooks})
33271 When not @code{#f}, this must be a G-expression that specifies a directory with
33272 scripts that will run when the OS is installed. It can also be a list of
33273 @code{(name . file-like)} pairs. For example:
33276 `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
33279 That will create a directory with one executable named @code{99-hello-world}
33280 and run it every time this variant is installed. If set to @code{#f}, hooks
33281 in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
33282 @item @code{proxy} (default: @code{#f})
33283 Optional HTTP proxy to use.
33284 @item @code{mirror} (default: @code{#f})
33285 The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
33286 The default varies depending on the distribution.
33287 @item @code{arch} (default: @code{#f})
33288 The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
33289 on an AArch64 host. Default is to use the current system architecture.
33290 @item @code{suite} (default: @code{"stable"})
33291 When set, this must be a Debian distribution ``suite'' such as @code{buster}
33292 or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
33293 @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
33294 List of extra packages that will get installed by dpkg in addition
33295 to the minimal system.
33296 @item @code{components} (default: @code{#f})
33297 When set, must be a list of Debian repository ``components''. For example
33298 @code{'("main" "contrib")}.
33299 @item @code{generate-cache?} (default: @code{#t})
33300 Whether to automatically cache the generated debootstrap archive.
33301 @item @code{clean-cache} (default: @code{14})
33302 Discard the cache after this amount of days. Use @code{#f} to never
33304 @item @code{partition-style} (default: @code{'msdos})
33305 The type of partition to create. When set, it must be one of
33306 @code{'msdos}, @code{'none} or a string.
33307 @item @code{partition-alignment} (default: @code{2048})
33308 Alignment of the partition in sectors.
33312 @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
33313 This is a helper procedure that creates a @code{ganeti-os-variant} record. It
33314 takes two parameters: a name and a @code{debootstrap-configuration} object.
33317 @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
33318 This is a helper procedure that creates a @code{ganeti-os} record. It takes
33319 a list of variants created with @code{debootstrap-variant}.
33322 @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
33323 This is a helper procedure that creates a @code{ganeti-os-variant} record for
33324 use with the Guix OS provider. It takes a name and a G-expression that returns
33325 a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
33326 Guix System configuration.
33329 @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
33330 This is a helper procedure that creates a @code{ganeti-os} record. It
33331 takes a list of variants produced by @code{guix-variant}.
33334 @defvr {Scheme Variable} %default-debootstrap-variants
33335 This is a convenience variable to make the debootstrap provider work
33336 ``out of the box'' without users having to declare variants manually. It
33337 contains a single debootstrap variant with the default configuration:
33340 (list (debootstrap-variant
33342 (debootstrap-configuration)))
33346 @defvr {Scheme Variable} %default-guix-variants
33347 This is a convenience variable to make the Guix OS provider work without
33348 additional configuration. It creates a virtual machine that has an SSH
33349 server, a serial console, and authorizes the Ganeti hosts SSH keys.
33352 (list (guix-variant
33354 (file-append ganeti-instance-guix
33355 "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
33359 Users can implement support for OS providers unbeknownst to Guix by extending
33360 the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
33366 (extension ".conf")
33368 (list (ganeti-os-variant
33370 (configuration (plain-file "bar" "this is fine"))))))
33373 That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
33374 to a file in the store with contents @code{this is fine}. It also creates
33375 @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
33377 Obviously this may not work for all OS providers out there. If you find the
33378 interface limiting, please reach out to @email{guix-devel@@gnu.org}.
33380 The rest of this section documents the various services that are included by
33381 @code{ganeti-service-type}.
33383 @defvr {Scheme Variable} ganeti-noded-service-type
33384 @command{ganeti-noded} is the daemon responsible for node-specific functions
33385 within the Ganeti system. The value of this service must be a
33386 @code{ganeti-noded-configuration} object.
33389 @deftp {Data Type} ganeti-noded-configuration
33390 This is the configuration for the @code{ganeti-noded} service.
33393 @item @code{ganeti} (default: @code{ganeti})
33394 The @code{ganeti} package to use for this service.
33396 @item @code{port} (default: @code{1811})
33397 The TCP port on which the node daemon listens for network requests.
33399 @item @code{address} (default: @code{"0.0.0.0"})
33400 The network address that the daemon will bind to. The default address means
33401 bind to all available addresses.
33403 @item @code{interface} (default: @code{#f})
33404 When this is set, it must be a specific network interface (e.g.@: @code{eth0})
33405 that the daemon will bind to.
33407 @item @code{max-clients} (default: @code{20})
33408 This sets a limit on the maximum number of simultaneous client connections
33409 that the daemon will handle. Connections above this count are accepted, but
33410 no responses will be sent until enough connections have closed.
33412 @item @code{ssl?} (default: @code{#t})
33413 Whether to use SSL/TLS to encrypt network communications. The certificate
33414 is automatically provisioned by the cluster and can be rotated with
33415 @command{gnt-cluster renew-crypto}.
33417 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
33418 This can be used to provide a specific encryption key for TLS communications.
33420 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
33421 This can be used to provide a specific certificate for TLS communications.
33423 @item @code{debug?} (default: @code{#f})
33424 When true, the daemon performs additional logging for debugging purposes.
33425 Note that this will leak encryption details to the log files, use with caution.
33430 @defvr {Scheme Variable} ganeti-confd-service-type
33431 @command{ganeti-confd} answers queries related to the configuration of a
33432 Ganeti cluster. The purpose of this daemon is to have a highly available
33433 and fast way to query cluster configuration values. It is automatically
33434 active on all @dfn{master candidates}. The value of this service must be a
33435 @code{ganeti-confd-configuration} object.
33439 @deftp {Data Type} ganeti-confd-configuration
33440 This is the configuration for the @code{ganeti-confd} service.
33443 @item @code{ganeti} (default: @code{ganeti})
33444 The @code{ganeti} package to use for this service.
33446 @item @code{port} (default: @code{1814})
33447 The UDP port on which to listen for network requests.
33449 @item @code{address} (default: @code{"0.0.0.0"})
33450 Network address that the daemon will bind to.
33452 @item @code{debug?} (default: @code{#f})
33453 When true, the daemon performs additional logging for debugging purposes.
33458 @defvr {Scheme Variable} ganeti-wconfd-service-type
33459 @command{ganeti-wconfd} is the daemon that has authoritative knowledge
33460 about the cluster configuration and is the only entity that can accept
33461 changes to it. All jobs that need to modify the configuration will do so
33462 by sending appropriate requests to this daemon. It only runs on the
33463 @dfn{master node} and will automatically disable itself on other nodes.
33465 The value of this service must be a
33466 @code{ganeti-wconfd-configuration} object.
33469 @deftp {Data Type} ganeti-wconfd-configuration
33470 This is the configuration for the @code{ganeti-wconfd} service.
33473 @item @code{ganeti} (default: @code{ganeti})
33474 The @code{ganeti} package to use for this service.
33476 @item @code{no-voting?} (default: @code{#f})
33477 The daemon will refuse to start if the majority of cluster nodes does not
33478 agree that it is running on the master node. Set to @code{#t} to start
33479 even if a quorum can not be reached (dangerous, use with caution).
33481 @item @code{debug?} (default: @code{#f})
33482 When true, the daemon performs additional logging for debugging purposes.
33487 @defvr {Scheme Variable} ganeti-luxid-service-type
33488 @command{ganeti-luxid} is a daemon used to answer queries related to the
33489 configuration and the current live state of a Ganeti cluster. Additionally,
33490 it is the authoritative daemon for the Ganeti job queue. Jobs can be
33491 submitted via this daemon and it schedules and starts them.
33493 It takes a @code{ganeti-luxid-configuration} object.
33496 @deftp {Data Type} ganeti-luxid-configuration
33497 This is the configuration for the @code{ganeti-luxid} service.
33500 @item @code{ganeti} (default: @code{ganeti})
33501 The @code{ganeti} package to use for this service.
33503 @item @code{no-voting?} (default: @code{#f})
33504 The daemon will refuse to start if it cannot verify that the majority of
33505 cluster nodes believes that it is running on the master node. Set to
33506 @code{#t} to ignore such checks and start anyway (this can be dangerous).
33508 @item @code{debug?} (default: @code{#f})
33509 When true, the daemon performs additional logging for debugging purposes.
33514 @defvr {Scheme Variable} ganeti-rapi-service-type
33515 @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
33516 the master node and can be used to perform cluster actions programmatically
33517 via a JSON-based RPC protocol.
33519 Most query operations are allowed without authentication (unless
33520 @var{require-authentication?} is set), whereas write operations require
33521 explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
33522 the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
33523 API documentation} for more information.
33525 The value of this service must be a @code{ganeti-rapi-configuration} object.
33528 @deftp {Data Type} ganeti-rapi-configuration
33529 This is the configuration for the @code{ganeti-rapi} service.
33532 @item @code{ganeti} (default: @code{ganeti})
33533 The @code{ganeti} package to use for this service.
33535 @item @code{require-authentication?} (default: @code{#f})
33536 Whether to require authentication even for read-only operations.
33538 @item @code{port} (default: @code{5080})
33539 The TCP port on which to listen to API requests.
33541 @item @code{address} (default: @code{"0.0.0.0"})
33542 The network address that the service will bind to. By default it listens
33543 on all configured addresses.
33545 @item @code{interface} (default: @code{#f})
33546 When set, it must specify a specific network interface such as @code{eth0}
33547 that the daemon will bind to.
33549 @item @code{max-clients} (default: @code{20})
33550 The maximum number of simultaneous client requests to handle. Further
33551 connections are allowed, but no responses are sent until enough connections
33554 @item @code{ssl?} (default: @code{#t})
33555 Whether to use SSL/TLS encryption on the RAPI port.
33557 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
33558 This can be used to provide a specific encryption key for TLS communications.
33560 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
33561 This can be used to provide a specific certificate for TLS communications.
33563 @item @code{debug?} (default: @code{#f})
33564 When true, the daemon performs additional logging for debugging purposes.
33565 Note that this will leak encryption details to the log files, use with caution.
33570 @defvr {Scheme Variable} ganeti-kvmd-service-type
33571 @command{ganeti-kvmd} is responsible for determining whether a given KVM
33572 instance was shut down by an administrator or a user. Normally Ganeti will
33573 restart an instance that was not stopped through Ganeti itself. If the
33574 cluster option @code{user_shutdown} is true, this daemon monitors the
33575 @code{QMP} socket provided by QEMU and listens for shutdown events, and
33576 marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
33577 it shuts down gracefully by itself.
33579 It takes a @code{ganeti-kvmd-configuration} object.
33582 @deftp {Data Type} ganeti-kvmd-configuration
33585 @item @code{ganeti} (default: @code{ganeti})
33586 The @code{ganeti} package to use for this service.
33588 @item @code{debug?} (default: @code{#f})
33589 When true, the daemon performs additional logging for debugging purposes.
33594 @defvr {Scheme Variable} ganeti-mond-service-type
33595 @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
33596 functionality. It is responsible for running data collectors and publish the
33597 collected information through a HTTP interface.
33599 It takes a @code{ganeti-mond-configuration} object.
33602 @deftp {Data Type} ganeti-mond-configuration
33605 @item @code{ganeti} (default: @code{ganeti})
33606 The @code{ganeti} package to use for this service.
33608 @item @code{port} (default: @code{1815})
33609 The port on which the daemon will listen.
33611 @item @code{address} (default: @code{"0.0.0.0"})
33612 The network address that the daemon will bind to. By default it binds to all
33613 available interfaces.
33615 @item @code{debug?} (default: @code{#f})
33616 When true, the daemon performs additional logging for debugging purposes.
33621 @defvr {Scheme Variable} ganeti-metad-service-type
33622 @command{ganeti-metad} is an optional daemon that can be used to provide
33623 information about the cluster to instances or OS install scripts.
33625 It takes a @code{ganeti-metad-configuration} object.
33628 @deftp {Data Type} ganeti-metad-configuration
33631 @item @code{ganeti} (default: @code{ganeti})
33632 The @code{ganeti} package to use for this service.
33634 @item @code{port} (default: @code{80})
33635 The port on which the daemon will listen.
33637 @item @code{address} (default: @code{#f})
33638 If set, the daemon will bind to this address only. If left unset, the behavior
33639 depends on the cluster configuration.
33641 @item @code{debug?} (default: @code{#f})
33642 When true, the daemon performs additional logging for debugging purposes.
33647 @defvr {Scheme Variable} ganeti-watcher-service-type
33648 @command{ganeti-watcher} is a script designed to run periodically and ensure
33649 the health of a cluster. It will automatically restart instances that have
33650 stopped without Ganeti's consent, and repairs DRBD links in case a node has
33651 rebooted. It also archives old cluster jobs and restarts Ganeti daemons
33652 that are not running. If the cluster parameter @code{ensure_node_health}
33653 is set, the watcher will also shutdown instances and DRBD devices if the
33654 node it is running on is declared offline by known master candidates.
33656 It can be paused on all nodes with @command{gnt-cluster watcher pause}.
33658 The service takes a @code{ganeti-watcher-configuration} object.
33661 @deftp {Data Type} ganeti-watcher-configuration
33664 @item @code{ganeti} (default: @code{ganeti})
33665 The @code{ganeti} package to use for this service.
33667 @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
33668 How often to run the script. The default is every five minutes.
33670 @item @code{rapi-ip} (default: @code{#f})
33671 This option needs to be specified only if the RAPI daemon is configured to use
33672 a particular interface or address. By default the cluster address is used.
33674 @item @code{job-age} (default: @code{(* 6 3600)})
33675 Archive cluster jobs older than this age, specified in seconds. The default
33676 is 6 hours. This keeps @command{gnt-job list} manageable.
33678 @item @code{verify-disks?} (default: @code{#t})
33679 If this is @code{#f}, the watcher will not try to repair broken DRBD links
33680 automatically. Administrators will need to use @command{gnt-cluster verify-disks}
33683 @item @code{debug?} (default: @code{#f})
33684 When @code{#t}, the script performs additional logging for debugging purposes.
33689 @defvr {Scheme Variable} ganeti-cleaner-service-type
33690 @command{ganeti-cleaner} is a script designed to run periodically and remove
33691 old files from the cluster. This service type controls two @dfn{cron jobs}:
33692 one intended for the master node that permanently purges old cluster jobs,
33693 and one intended for every node that removes expired X509 certificates, keys,
33694 and outdated @command{ganeti-watcher} information. Like all Ganeti services,
33695 it is safe to include even on non-master nodes as it will disable itself as
33698 It takes a @code{ganeti-cleaner-configuration} object.
33701 @deftp {Data Type} ganeti-cleaner-configuration
33704 @item @code{ganeti} (default: @code{ganeti})
33705 The @code{ganeti} package to use for the @command{gnt-cleaner} command.
33707 @item @code{master-schedule} (default: @code{"45 1 * * *"})
33708 How often to run the master cleaning job. The default is once per day, at
33711 @item @code{node-schedule} (default: @code{"45 2 * * *"})
33712 How often to run the node cleaning job. The default is once per day, at
33718 @node Version Control Services
33719 @subsection Version Control Services
33721 The @code{(gnu services version-control)} module provides a service to
33722 allow remote access to local Git repositories. There are three options:
33723 the @code{git-daemon-service}, which provides access to repositories via
33724 the @code{git://} unsecured TCP-based protocol, extending the
33725 @code{nginx} web server to proxy some requests to
33726 @code{git-http-backend}, or providing a web interface with
33727 @code{cgit-service-type}.
33729 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
33731 Return a service that runs @command{git daemon}, a simple TCP server to
33732 expose repositories over the Git protocol for anonymous access.
33734 The optional @var{config} argument should be a
33735 @code{<git-daemon-configuration>} object, by default it allows read-only
33736 access to exported@footnote{By creating the magic file
33737 @file{git-daemon-export-ok} in the repository directory.} repositories under
33742 @deftp {Data Type} git-daemon-configuration
33743 Data type representing the configuration for @code{git-daemon-service}.
33746 @item @code{package} (default: @code{git})
33747 Package object of the Git distributed version control system.
33749 @item @code{export-all?} (default: @code{#f})
33750 Whether to allow access for all Git repositories, even if they do not
33751 have the @file{git-daemon-export-ok} file.
33753 @item @code{base-path} (default: @file{/srv/git})
33754 Whether to remap all the path requests as relative to the given path.
33755 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
33756 @samp{example.com}, then if you later try to pull
33757 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
33758 path as @file{/srv/git/hello.git}.
33760 @item @code{user-path} (default: @code{#f})
33761 Whether to allow @code{~user} notation to be used in requests. When
33762 specified with empty string, requests to
33763 @indicateurl{git://host/~alice/foo} is taken as a request to access
33764 @code{foo} repository in the home directory of user @code{alice}. If
33765 @code{(user-path "@var{path}")} is specified, the same request is taken
33766 as a request to access @file{@var{path}/foo} repository in the home
33767 directory of user @code{alice}.
33769 @item @code{listen} (default: @code{'()})
33770 Whether to listen on specific IP addresses or hostnames, defaults to
33773 @item @code{port} (default: @code{#f})
33774 Whether to listen on an alternative port, which defaults to 9418.
33776 @item @code{whitelist} (default: @code{'()})
33777 If not empty, only allow access to this list of directories.
33779 @item @code{extra-options} (default: @code{'()})
33780 Extra options will be passed to @command{git daemon}, please run
33781 @command{man git-daemon} for more information.
33786 The @code{git://} protocol lacks authentication. When you pull from a
33787 repository fetched via @code{git://}, you don't know whether the data you
33788 receive was modified or is even coming from the specified host, and your
33789 connection is subject to eavesdropping. It's better to use an authenticated
33790 and encrypted transport, such as @code{https}. Although Git allows you
33791 to serve repositories using unsophisticated file-based web servers,
33792 there is a faster protocol implemented by the @code{git-http-backend}
33793 program. This program is the back-end of a proper Git web service. It
33794 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
33795 on running the necessary @code{fcgiwrap} daemon.
33797 Guix has a separate configuration data type for serving Git repositories
33800 @deftp {Data Type} git-http-configuration
33801 Data type representing the configuration for a future
33802 @code{git-http-service-type}; can currently be used to configure Nginx
33803 through @code{git-http-nginx-location-configuration}.
33806 @item @code{package} (default: @var{git})
33807 Package object of the Git distributed version control system.
33809 @item @code{git-root} (default: @file{/srv/git})
33810 Directory containing the Git repositories to expose to the world.
33812 @item @code{export-all?} (default: @code{#f})
33813 Whether to expose access for all Git repositories in @var{git-root},
33814 even if they do not have the @file{git-daemon-export-ok} file.
33816 @item @code{uri-path} (default: @samp{/git/})
33817 Path prefix for Git access. With the default @samp{/git/} prefix, this
33818 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
33819 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
33820 with this prefix are not passed on to this Git instance.
33822 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
33823 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
33828 There is no @code{git-http-service-type}, currently; instead you can
33829 create an @code{nginx-location-configuration} from a
33830 @code{git-http-configuration} and then add that location to a web
33833 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
33834 [config=(git-http-configuration)]
33835 Compute an @code{nginx-location-configuration} that corresponds to the
33836 given Git http configuration. An example nginx service definition to
33837 serve the default @file{/srv/git} over HTTPS might be:
33840 (service nginx-service-type
33841 (nginx-configuration
33844 (nginx-server-configuration
33845 (listen '("443 ssl"))
33846 (server-name "git.my-host.org")
33848 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
33849 (ssl-certificate-key
33850 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
33853 (git-http-nginx-location-configuration
33854 (git-http-configuration (uri-path "/"))))))))))
33857 This example assumes that you are using Let's Encrypt to get your TLS
33858 certificate. @xref{Certificate Services}. The default @code{certbot}
33859 service will redirect all HTTP traffic on @code{git.my-host.org} to
33860 HTTPS@. You will also need to add an @code{fcgiwrap} proxy to your
33861 system services. @xref{Web Services}.
33864 @subsubheading Cgit Service
33866 @cindex Cgit service
33867 @cindex Git, web interface
33868 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
33869 repositories written in C.
33871 The following example will configure the service with default values.
33872 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
33875 (service cgit-service-type)
33878 The @code{file-object} type designates either a file-like object
33879 (@pxref{G-Expressions, file-like objects}) or a string.
33881 @c %start of fragment
33883 Available @code{cgit-configuration} fields are:
33885 @deftypevr {@code{cgit-configuration} parameter} package package
33890 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
33891 NGINX configuration.
33895 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
33896 Specifies a command which will be invoked to format the content of about
33897 pages (both top-level and for each repository).
33899 Defaults to @samp{""}.
33903 @deftypevr {@code{cgit-configuration} parameter} string agefile
33904 Specifies a path, relative to each repository path, which can be used to
33905 specify the date and time of the youngest commit in the repository.
33907 Defaults to @samp{""}.
33911 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
33912 Specifies a command that will be invoked for authenticating repository
33915 Defaults to @samp{""}.
33919 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
33920 Flag which, when set to @samp{age}, enables date ordering in the branch
33921 ref list, and when set @samp{name} enables ordering by branch name.
33923 Defaults to @samp{"name"}.
33927 @deftypevr {@code{cgit-configuration} parameter} string cache-root
33928 Path used to store the cgit cache entries.
33930 Defaults to @samp{"/var/cache/cgit"}.
33934 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
33935 Number which specifies the time-to-live, in minutes, for the cached
33936 version of repository pages accessed with a fixed SHA1.
33938 Defaults to @samp{-1}.
33942 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
33943 Number which specifies the time-to-live, in minutes, for the cached
33944 version of repository pages accessed without a fixed SHA1.
33946 Defaults to @samp{5}.
33950 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
33951 Number which specifies the time-to-live, in minutes, for the cached
33952 version of the repository summary page.
33954 Defaults to @samp{5}.
33958 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
33959 Number which specifies the time-to-live, in minutes, for the cached
33960 version of the repository index page.
33962 Defaults to @samp{5}.
33966 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
33967 Number which specifies the time-to-live, in minutes, for the result of
33968 scanning a path for Git repositories.
33970 Defaults to @samp{15}.
33974 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
33975 Number which specifies the time-to-live, in minutes, for the cached
33976 version of the repository about page.
33978 Defaults to @samp{15}.
33982 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
33983 Number which specifies the time-to-live, in minutes, for the cached
33984 version of snapshots.
33986 Defaults to @samp{5}.
33990 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
33991 The maximum number of entries in the cgit cache. When set to @samp{0},
33992 caching is disabled.
33994 Defaults to @samp{0}.
33998 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
33999 Sort items in the repo list case sensitively.
34001 Defaults to @samp{#t}.
34005 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
34006 List of common prefixes which, when combined with a repository URL,
34007 generates valid clone URLs for the repository.
34009 Defaults to @samp{()}.
34013 @deftypevr {@code{cgit-configuration} parameter} list clone-url
34014 List of @code{clone-url} templates.
34016 Defaults to @samp{()}.
34020 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
34021 Command which will be invoked to format commit messages.
34023 Defaults to @samp{""}.
34027 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
34028 Flag which, when set to @samp{date}, enables strict date ordering in the
34029 commit log, and when set to @samp{topo} enables strict topological
34032 Defaults to @samp{"git log"}.
34036 @deftypevr {@code{cgit-configuration} parameter} file-object css
34037 URL which specifies the css document to include in all cgit pages.
34039 Defaults to @samp{"/share/cgit/cgit.css"}.
34043 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
34044 Specifies a command which will be invoked to format names and email
34045 address of committers, authors, and taggers, as represented in various
34046 places throughout the cgit interface.
34048 Defaults to @samp{""}.
34052 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
34053 Flag which, when set to @samp{#t}, will make cgit generate a HTML
34054 fragment suitable for embedding in other HTML pages.
34056 Defaults to @samp{#f}.
34060 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
34061 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
34062 commit history graph to the left of the commit messages in the
34063 repository log page.
34065 Defaults to @samp{#f}.
34069 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
34070 Flag which, when set to @samp{#t}, allows all filter settings to be
34071 overridden in repository-specific cgitrc files.
34073 Defaults to @samp{#f}.
34077 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
34078 Flag which, when set to @samp{#t}, allows users to follow a file in the
34081 Defaults to @samp{#f}.
34085 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
34086 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
34089 Defaults to @samp{#t}.
34093 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
34094 Flag which, when set to @samp{#t}, will make cgit generate extra links
34095 "summary", "commit", "tree" for each repo in the repository index.
34097 Defaults to @samp{#f}.
34101 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
34102 Flag which, when set to @samp{#t}, will make cgit display the owner of
34103 each repo in the repository index.
34105 Defaults to @samp{#t}.
34109 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
34110 Flag which, when set to @samp{#t}, will make cgit print the number of
34111 modified files for each commit on the repository log page.
34113 Defaults to @samp{#f}.
34117 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
34118 Flag which, when set to @samp{#t}, will make cgit print the number of
34119 added and removed lines for each commit on the repository log page.
34121 Defaults to @samp{#f}.
34125 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
34126 Flag which, when set to @code{#t}, will make cgit display remote
34127 branches in the summary and refs views.
34129 Defaults to @samp{#f}.
34133 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
34134 Flag which, when set to @code{1}, will make cgit use the subject of the
34135 parent commit as link text when generating links to parent commits in
34138 Defaults to @samp{#f}.
34142 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
34143 Flag which, when set to @samp{#t}, will make cgit use the subject of the
34144 parent commit as link text when generating links to parent commits in
34147 Defaults to @samp{#f}.
34151 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
34152 Flag which, when set to @samp{#t}, will make cgit generate linenumber
34153 links for plaintext blobs printed in the tree view.
34155 Defaults to @samp{#t}.
34159 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
34160 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
34161 set any repo specific settings.
34163 Defaults to @samp{#f}.
34167 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
34168 URL used as link to a shortcut icon for cgit.
34170 Defaults to @samp{"/favicon.ico"}.
34174 @deftypevr {@code{cgit-configuration} parameter} string footer
34175 The content of the file specified with this option will be included
34176 verbatim at the bottom of all pages (i.e.@: it replaces the standard
34177 "generated by..."@: message).
34179 Defaults to @samp{""}.
34183 @deftypevr {@code{cgit-configuration} parameter} string head-include
34184 The content of the file specified with this option will be included
34185 verbatim in the HTML HEAD section on all pages.
34187 Defaults to @samp{""}.
34191 @deftypevr {@code{cgit-configuration} parameter} string header
34192 The content of the file specified with this option will be included
34193 verbatim at the top of all pages.
34195 Defaults to @samp{""}.
34199 @deftypevr {@code{cgit-configuration} parameter} file-object include
34200 Name of a configfile to include before the rest of the current config-
34203 Defaults to @samp{""}.
34207 @deftypevr {@code{cgit-configuration} parameter} string index-header
34208 The content of the file specified with this option will be included
34209 verbatim above the repository index.
34211 Defaults to @samp{""}.
34215 @deftypevr {@code{cgit-configuration} parameter} string index-info
34216 The content of the file specified with this option will be included
34217 verbatim below the heading on the repository index page.
34219 Defaults to @samp{""}.
34223 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
34224 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
34225 in the servers timezone.
34227 Defaults to @samp{#f}.
34231 @deftypevr {@code{cgit-configuration} parameter} file-object logo
34232 URL which specifies the source of an image which will be used as a logo
34235 Defaults to @samp{"/share/cgit/cgit.png"}.
34239 @deftypevr {@code{cgit-configuration} parameter} string logo-link
34240 URL loaded when clicking on the cgit logo image.
34242 Defaults to @samp{""}.
34246 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
34247 Command which will be invoked to format the Owner column of the main
34250 Defaults to @samp{""}.
34254 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
34255 Number of items to display in atom feeds view.
34257 Defaults to @samp{10}.
34261 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
34262 Number of entries to list per page in "log" view.
34264 Defaults to @samp{50}.
34268 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
34269 Number of commit message characters to display in "log" view.
34271 Defaults to @samp{80}.
34275 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
34276 Specifies the number of entries to list per page on the repository index
34279 Defaults to @samp{50}.
34283 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
34284 Specifies the maximum number of repo description characters to display
34285 on the repository index page.
34287 Defaults to @samp{80}.
34291 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
34292 Specifies the maximum size of a blob to display HTML for in KBytes.
34294 Defaults to @samp{0}.
34298 @deftypevr {@code{cgit-configuration} parameter} string max-stats
34299 Maximum statistics period. Valid values are @samp{week},@samp{month},
34300 @samp{quarter} and @samp{year}.
34302 Defaults to @samp{""}.
34306 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
34307 Mimetype for the specified filename extension.
34309 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
34310 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
34311 "image/png") (svg "image/svg+xml"))}.
34315 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
34316 Specifies the file to use for automatic mimetype lookup.
34318 Defaults to @samp{""}.
34322 @deftypevr {@code{cgit-configuration} parameter} string module-link
34323 Text which will be used as the formatstring for a hyperlink when a
34324 submodule is printed in a directory listing.
34326 Defaults to @samp{""}.
34330 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
34331 If set to the value @samp{#t} caching will be disabled.
34333 Defaults to @samp{#f}.
34337 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
34338 If set to @samp{#t} showing full author email addresses will be
34341 Defaults to @samp{#f}.
34345 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
34346 Flag which, when set to @samp{#t}, will make cgit omit the standard
34347 header on all pages.
34349 Defaults to @samp{#f}.
34353 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
34354 A list of subdirectories inside of @code{repository-directory}, relative
34355 to it, that should loaded as Git repositories. An empty list means that
34356 all subdirectories will be loaded.
34358 Defaults to @samp{()}.
34362 @deftypevr {@code{cgit-configuration} parameter} file-object readme
34363 Text which will be used as default value for @code{cgit-repo-readme}.
34365 Defaults to @samp{""}.
34369 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
34370 If set to @code{#t} and @code{repository-directory} is enabled, if any
34371 repositories are found with a suffix of @code{.git}, this suffix will be
34372 removed for the URL and name.
34374 Defaults to @samp{#f}.
34378 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
34379 Maximum number of files to consider when detecting renames.
34381 Defaults to @samp{-1}.
34385 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
34386 The way in which repositories in each section are sorted.
34388 Defaults to @samp{""}.
34392 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
34393 Text used as content for the @code{robots} meta-tag.
34395 Defaults to @samp{("noindex" "nofollow")}.
34399 @deftypevr {@code{cgit-configuration} parameter} string root-desc
34400 Text printed below the heading on the repository index page.
34402 Defaults to @samp{"a fast webinterface for the git dscm"}.
34406 @deftypevr {@code{cgit-configuration} parameter} string root-readme
34407 The content of the file specified with this option will be included
34408 verbatim below the ``about'' link on the repository index page.
34410 Defaults to @samp{""}.
34414 @deftypevr {@code{cgit-configuration} parameter} string root-title
34415 Text printed as heading on the repository index page.
34417 Defaults to @samp{""}.
34421 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
34422 If set to @samp{#t} and repository-directory is enabled,
34423 repository-directory will recurse into directories whose name starts
34424 with a period. Otherwise, repository-directory will stay away from such
34425 directories, considered as ``hidden''. Note that this does not apply to
34426 the @file{.git} directory in non-bare repos.
34428 Defaults to @samp{#f}.
34432 @deftypevr {@code{cgit-configuration} parameter} list snapshots
34433 Text which specifies the default set of snapshot formats that cgit
34434 generates links for.
34436 Defaults to @samp{()}.
34440 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
34441 Name of the directory to scan for repositories (represents
34444 Defaults to @samp{"/srv/git"}.
34448 @deftypevr {@code{cgit-configuration} parameter} string section
34449 The name of the current repository section - all repositories defined
34450 after this option will inherit the current section name.
34452 Defaults to @samp{""}.
34456 @deftypevr {@code{cgit-configuration} parameter} string section-sort
34457 Flag which, when set to @samp{1}, will sort the sections on the
34458 repository listing by name.
34460 Defaults to @samp{""}.
34464 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
34465 A number which, if defined prior to repository-directory, specifies how
34466 many path elements from each repo path to use as a default section name.
34468 Defaults to @samp{0}.
34472 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
34473 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
34476 Defaults to @samp{#f}.
34480 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
34481 Specifies a command which will be invoked to format plaintext blobs in
34484 Defaults to @samp{""}.
34488 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
34489 Specifies the number of branches to display in the repository ``summary''
34492 Defaults to @samp{10}.
34496 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
34497 Specifies the number of log entries to display in the repository
34500 Defaults to @samp{10}.
34504 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
34505 Specifies the number of tags to display in the repository ``summary''
34508 Defaults to @samp{10}.
34512 @deftypevr {@code{cgit-configuration} parameter} string strict-export
34513 Filename which, if specified, needs to be present within the repository
34514 for cgit to allow access to that repository.
34516 Defaults to @samp{""}.
34520 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
34521 URL which, if specified, will be used as root for all cgit links.
34523 Defaults to @samp{"/"}.
34527 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
34528 A list of @dfn{cgit-repo} records to use with config.
34530 Defaults to @samp{()}.
34532 Available @code{repository-cgit-configuration} fields are:
34534 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
34535 A mask of snapshot formats for this repo that cgit generates links for,
34536 restricted by the global @code{snapshots} setting.
34538 Defaults to @samp{()}.
34542 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
34543 Override the default @code{source-filter}.
34545 Defaults to @samp{""}.
34549 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
34550 The relative URL used to access the repository.
34552 Defaults to @samp{""}.
34556 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
34557 Override the default @code{about-filter}.
34559 Defaults to @samp{""}.
34563 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
34564 Flag which, when set to @samp{age}, enables date ordering in the branch
34565 ref list, and when set to @samp{name} enables ordering by branch name.
34567 Defaults to @samp{""}.
34571 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
34572 A list of URLs which can be used to clone repo.
34574 Defaults to @samp{()}.
34578 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
34579 Override the default @code{commit-filter}.
34581 Defaults to @samp{""}.
34585 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
34586 Flag which, when set to @samp{date}, enables strict date ordering in the
34587 commit log, and when set to @samp{topo} enables strict topological
34590 Defaults to @samp{""}.
34594 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
34595 The name of the default branch for this repository. If no such branch
34596 exists in the repository, the first branch name (when sorted) is used as
34597 default instead. By default branch pointed to by HEAD, or ``master'' if
34598 there is no suitable HEAD.
34600 Defaults to @samp{""}.
34604 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
34605 The value to show as repository description.
34607 Defaults to @samp{""}.
34611 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
34612 The value to show as repository homepage.
34614 Defaults to @samp{""}.
34618 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
34619 Override the default @code{email-filter}.
34621 Defaults to @samp{""}.
34625 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
34626 A flag which can be used to disable the global setting
34627 @code{enable-commit-graph?}.
34629 Defaults to @samp{disabled}.
34633 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
34634 A flag which can be used to disable the global setting
34635 @code{enable-log-filecount?}.
34637 Defaults to @samp{disabled}.
34641 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
34642 A flag which can be used to disable the global setting
34643 @code{enable-log-linecount?}.
34645 Defaults to @samp{disabled}.
34649 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
34650 Flag which, when set to @code{#t}, will make cgit display remote
34651 branches in the summary and refs views.
34653 Defaults to @samp{disabled}.
34657 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
34658 A flag which can be used to override the global setting
34659 @code{enable-subject-links?}.
34661 Defaults to @samp{disabled}.
34665 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
34666 A flag which can be used to override the global setting
34667 @code{enable-html-serving?}.
34669 Defaults to @samp{disabled}.
34673 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
34674 Flag which, when set to @code{#t}, hides the repository from the
34677 Defaults to @samp{#f}.
34681 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
34682 Flag which, when set to @samp{#t}, ignores the repository.
34684 Defaults to @samp{#f}.
34688 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
34689 URL which specifies the source of an image which will be used as a logo
34690 on this repo’s pages.
34692 Defaults to @samp{""}.
34696 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
34697 URL loaded when clicking on the cgit logo image.
34699 Defaults to @samp{""}.
34703 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
34704 Override the default @code{owner-filter}.
34706 Defaults to @samp{""}.
34710 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
34711 Text which will be used as the formatstring for a hyperlink when a
34712 submodule is printed in a directory listing. The arguments for the
34713 formatstring are the path and SHA1 of the submodule commit.
34715 Defaults to @samp{""}.
34719 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
34720 Text which will be used as the formatstring for a hyperlink when a
34721 submodule with the specified subdirectory path is printed in a directory
34724 Defaults to @samp{()}.
34728 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
34729 Override the default maximum statistics period.
34731 Defaults to @samp{""}.
34735 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
34736 The value to show as repository name.
34738 Defaults to @samp{""}.
34742 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
34743 A value used to identify the owner of the repository.
34745 Defaults to @samp{""}.
34749 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
34750 An absolute path to the repository directory.
34752 Defaults to @samp{""}.
34756 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
34757 A path (relative to repo) which specifies a file to include verbatim as
34758 the ``About'' page for this repo.
34760 Defaults to @samp{""}.
34764 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
34765 The name of the current repository section - all repositories defined
34766 after this option will inherit the current section name.
34768 Defaults to @samp{""}.
34772 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
34773 Extra options will be appended to cgitrc file.
34775 Defaults to @samp{()}.
34781 @deftypevr {@code{cgit-configuration} parameter} list extra-options
34782 Extra options will be appended to cgitrc file.
34784 Defaults to @samp{()}.
34789 @c %end of fragment
34791 However, it could be that you just want to get a @code{cgitrc} up and
34792 running. In that case, you can pass an @code{opaque-cgit-configuration}
34793 as a record to @code{cgit-service-type}. As its name indicates, an
34794 opaque configuration does not have easy reflective capabilities.
34796 Available @code{opaque-cgit-configuration} fields are:
34798 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
34802 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
34803 The contents of the @code{cgitrc}, as a string.
34806 For example, if your @code{cgitrc} is just the empty string, you
34807 could instantiate a cgit service like this:
34810 (service cgit-service-type
34811 (opaque-cgit-configuration
34815 @subsubheading Gitolite Service
34817 @cindex Gitolite service
34818 @cindex Git, hosting
34819 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
34820 repositories on a central server.
34822 Gitolite can handle multiple repositories and users, and supports flexible
34823 configuration of the permissions for the users on the repositories.
34825 The following example will configure Gitolite using the default @code{git}
34826 user, and the provided SSH public key.
34829 (service gitolite-service-type
34830 (gitolite-configuration
34831 (admin-pubkey (plain-file
34833 "ssh-rsa AAAA... guix@@example.com"))))
34836 Gitolite is configured through a special admin repository which you can clone,
34837 for example, if you setup Gitolite on @code{example.com}, you would run the
34838 following command to clone the admin repository.
34841 git clone git@@example.com:gitolite-admin
34844 When the Gitolite service is activated, the provided @code{admin-pubkey} will
34845 be inserted in to the @file{keydir} directory in the gitolite-admin
34846 repository. If this results in a change in the repository, it will be
34847 committed using the message ``gitolite setup by GNU Guix''.
34849 @deftp {Data Type} gitolite-configuration
34850 Data type representing the configuration for @code{gitolite-service-type}.
34853 @item @code{package} (default: @var{gitolite})
34854 Gitolite package to use.
34856 @item @code{user} (default: @var{git})
34857 User to use for Gitolite. This will be user that you use when accessing
34860 @item @code{group} (default: @var{git})
34861 Group to use for Gitolite.
34863 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
34864 Directory in which to store the Gitolite configuration and repositories.
34866 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
34867 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
34868 representing the configuration for Gitolite.
34870 @item @code{admin-pubkey} (default: @var{#f})
34871 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
34872 setup Gitolite. This will be inserted in to the @file{keydir} directory
34873 within the gitolite-admin repository.
34875 To specify the SSH key as a string, use the @code{plain-file} function.
34878 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
34884 @deftp {Data Type} gitolite-rc-file
34885 Data type representing the Gitolite RC file.
34888 @item @code{umask} (default: @code{#o0077})
34889 This controls the permissions Gitolite sets on the repositories and their
34892 A value like @code{#o0027} will give read access to the group used by Gitolite
34893 (by default: @code{git}). This is necessary when using Gitolite with software
34894 like cgit or gitweb.
34896 @item @code{unsafe-pattern} (default: @code{#f})
34897 An optional Perl regular expression for catching unsafe configurations in
34898 the configuration file. See
34899 @uref{https://gitolite.com/gitolite/git-config.html#compensating-for-unsafe_patt,
34900 Gitolite's documentation} for more information.
34902 When the value is not @code{#f}, it should be a string containing a Perl
34903 regular expression, such as @samp{"[`~#\$\&()|;<>]"}, which is the default
34904 value used by gitolite. It rejects any special character in configuration
34905 that might be interpreted by a shell, which is useful when sharing the
34906 administration burden with other people that do not otherwise have shell
34907 access on the server.
34909 @item @code{git-config-keys} (default: @code{""})
34910 Gitolite allows you to set git config values using the @samp{config}
34911 keyword. This setting allows control over the config keys to accept.
34913 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
34914 Set the role names allowed to be used by users running the perms command.
34916 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
34917 This setting controls the commands and features to enable within Gitolite.
34923 @subsubheading Gitile Service
34925 @cindex Gitile service
34927 @uref{https://git.lepiller.eu/gitile, Gitile} is a Git forge for viewing
34928 public git repository contents from a web browser.
34930 Gitile works best in collaboration with Gitolite, and will serve the public
34931 repositories from Gitolite by default. The service should listen only on
34932 a local port, and a webserver should be configured to serve static resources.
34933 The gitile service provides an easy way to extend the Nginx service for
34934 that purpose (@pxref{NGINX}).
34936 The following example will configure Gitile to serve repositories from a
34937 custom location, with some default messages for the home page and the
34941 (service gitile-service-type
34942 (gitile-configuration
34943 (repositories "/srv/git")
34944 (base-git-url "https://myweb.site/git")
34945 (index-title "My git repositories")
34946 (intro '((p "This is all my public work!")))
34947 (footer '((p "This is the end")))
34948 (nginx-server-block
34949 (nginx-server-configuration
34951 "/etc/letsencrypt/live/myweb.site/fullchain.pem")
34952 (ssl-certificate-key
34953 "/etc/letsencrypt/live/myweb.site/privkey.pem")
34954 (listen '("443 ssl http2" "[::]:443 ssl http2"))
34957 ;; Allow for https anonymous fetch on /git/ urls.
34958 (git-http-nginx-location-configuration
34959 (git-http-configuration
34961 (git-root "/var/lib/gitolite/repositories")))))))))
34964 In addition to the configuration record, you should configure your git
34965 repositories to contain some optional information. First, your public
34966 repositories need to contain the @file{git-daemon-export-ok} magic file
34967 that allows Git to export the repository. Gitile uses the presence of this
34968 file to detect public repositories it should make accessible. To do so with
34969 Gitolite for instance, modify your @file{conf/gitolite.conf} to include
34970 this in the repositories you want to make public:
34977 In addition, Gitile can read the repository configuration to display more
34978 information on the repository. Gitile uses the gitweb namespace for its
34979 configuration. As an example, you can use the following in your
34980 @file{conf/gitolite.conf}:
34985 desc = A long description, optionally with <i>HTML</i>, shown on the index page
34986 config gitweb.name = The Foo Project
34987 config gitweb.synopsis = A short description, shown on the main page of the project
34990 Do not forget to commit and push these changes once you are satisfied. You
34991 may need to change your gitolite configuration to allow the previous
34992 configuration options to be set. One way to do that is to add the
34993 following service definition:
34996 (service gitolite-service-type
34997 (gitolite-configuration
34998 (admin-pubkey (local-file "key.pub"))
35002 ;; Allow to set any configuration key
35003 (git-config-keys ".*")
35004 ;; Allow any text as a valid configuration value
35005 (unsafe-patt "^$")))))
35008 @deftp {Data Type} gitile-configuration
35009 Data type representing the configuration for @code{gitile-service-type}.
35012 @item @code{package} (default: @var{gitile})
35013 Gitile package to use.
35015 @item @code{host} (default: @code{"localhost"})
35016 The host on which gitile is listening.
35018 @item @code{port} (default: @code{8080})
35019 The port on which gitile is listening.
35021 @item @code{database} (default: @code{"/var/lib/gitile/gitile-db.sql"})
35022 The location of the database.
35024 @item @code{repositories} (default: @code{"/var/lib/gitolite/repositories"})
35025 The location of the repositories. Note that only public repositories will
35026 be shown by Gitile. To make a repository public, add an empty
35027 @file{git-daemon-export-ok} file at the root of that repository.
35029 @item @code{base-git-url}
35030 The base git url that will be used to show clone commands.
35032 @item @code{index-title} (default: @code{"Index"})
35033 The page title for the index page that lists all the available repositories.
35035 @item @code{intro} (default: @code{'()})
35036 The intro content, as a list of sxml expressions. This is shown above the list
35037 of repositories, on the index page.
35039 @item @code{footer} (default: @code{'()})
35040 The footer content, as a list of sxml expressions. This is shown on every
35041 page served by Gitile.
35043 @item @code{nginx-server-block}
35044 An nginx server block that will be extended and used as a reverse proxy by
35045 Gitile to serve its pages, and as a normal web server to serve its assets.
35047 You can use this block to add more custom URLs to your domain, such as a
35048 @code{/git/} URL for anonymous clones, or serving any other files you would
35054 @node Game Services
35055 @subsection Game Services
35057 @subsubheading The Battle for Wesnoth Service
35059 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
35060 based tactical strategy game, with several single player campaigns, and
35061 multiplayer games (both networked and local).
35063 @defvar {Scheme Variable} wesnothd-service-type
35064 Service type for the wesnothd service. Its value must be a
35065 @code{wesnothd-configuration} object. To run wesnothd in the default
35066 configuration, instantiate it as:
35069 (service wesnothd-service-type)
35073 @deftp {Data Type} wesnothd-configuration
35074 Data type representing the configuration of @command{wesnothd}.
35077 @item @code{package} (default: @code{wesnoth-server})
35078 The wesnoth server package to use.
35080 @item @code{port} (default: @code{15000})
35081 The port to bind the server to.
35086 @node PAM Mount Service
35087 @subsection PAM Mount Service
35090 The @code{(gnu services pam-mount)} module provides a service allowing
35091 users to mount volumes when they log in. It should be able to mount any
35092 volume format supported by the system.
35094 @defvar {Scheme Variable} pam-mount-service-type
35095 Service type for PAM Mount support.
35098 @deftp {Data Type} pam-mount-configuration
35099 Data type representing the configuration of PAM Mount.
35101 It takes the following parameters:
35105 The configuration rules that will be used to generate
35106 @file{/etc/security/pam_mount.conf.xml}.
35108 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
35109 Guile Reference Manual}), and the default ones don't mount anything for
35113 `((debug (@@ (enable "0")))
35114 (mntoptions (@@ (allow ,(string-join
35115 '("nosuid" "nodev" "loop"
35116 "encryption" "fsck" "nonempty"
35117 "allow_root" "allow_other")
35119 (mntoptions (@@ (require "nosuid,nodev")))
35120 (logout (@@ (wait "0")
35124 (mkmountpoint (@@ (enable "1")
35128 Some @code{volume} elements must be added to automatically mount volumes
35129 at login. Here's an example allowing the user @code{alice} to mount her
35130 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
35131 the partition where he stores his data:
35134 (define pam-mount-rules
35135 `((debug (@@ (enable "0")))
35136 (volume (@@ (user "alice")
35139 (mountpoint "/home/alice")))
35140 (volume (@@ (user "bob")
35143 (mountpoint "/home/bob/data")
35144 (options "defaults,autodefrag,compress")))
35145 (mntoptions (@@ (allow ,(string-join
35146 '("nosuid" "nodev" "loop"
35147 "encryption" "fsck" "nonempty"
35148 "allow_root" "allow_other")
35150 (mntoptions (@@ (require "nosuid,nodev")))
35151 (logout (@@ (wait "0")
35155 (mkmountpoint (@@ (enable "1")
35156 (remove "true")))))
35158 (service pam-mount-service-type
35159 (pam-mount-configuration
35160 (rules pam-mount-rules)))
35163 The complete list of possible options can be found in the man page for
35164 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
35169 @node Guix Services
35170 @subsection Guix Services
35172 @subsubheading Guix Build Coordinator
35173 The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
35174 Coordinator} aids in distributing derivation builds among machines
35175 running an @dfn{agent}. The build daemon is still used to build the
35176 derivations, but the Guix Build Coordinator manages allocating builds
35177 and working with the results.
35179 The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
35180 more connected @dfn{agent} processes. The coordinator process handles
35181 clients submitting builds, and allocating builds to agents. The agent
35182 processes talk to a build daemon to actually perform the builds, then
35183 send the results back to the coordinator.
35185 There is a script to run the coordinator component of the Guix Build
35186 Coordinator, but the Guix service uses a custom Guile script instead, to
35187 provide better integration with G-expressions used in the configuration.
35189 @defvar {Scheme Variable} guix-build-coordinator-service-type
35190 Service type for the Guix Build Coordinator. Its value must be a
35191 @code{guix-build-coordinator-configuration} object.
35194 @deftp {Data Type} guix-build-coordinator-configuration
35195 Data type representing the configuration of the Guix Build Coordinator.
35198 @item @code{package} (default: @code{guix-build-coordinator})
35199 The Guix Build Coordinator package to use.
35201 @item @code{user} (default: @code{"guix-build-coordinator"})
35202 The system user to run the service as.
35204 @item @code{group} (default: @code{"guix-build-coordinator"})
35205 The system group to run the service as.
35207 @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
35208 The URI to use for the database.
35210 @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
35211 The URI describing how to listen to requests from agent processes.
35213 @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
35214 The URI describing how to listen to requests from clients. The client
35215 API allows submitting builds and currently isn't authenticated, so take
35216 care when configuring this value.
35218 @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
35219 A G-expression for the allocation strategy to be used. This is a
35220 procedure that takes the datastore as an argument and populates the
35221 allocation plan in the database.
35223 @item @code{hooks} (default: @var{'()})
35224 An association list of hooks. These provide a way to execute arbitrary
35225 code upon certain events, like a build result being processed.
35227 @item @code{parallel-hooks} (default: @var{'()})
35228 Hooks can be configured to run in parallel. This parameter is an
35229 association list of hooks to do in parallel, where the key is the symbol
35230 for the hook and the value is the number of threads to run.
35232 @item @code{guile} (default: @code{guile-3.0-latest})
35233 The Guile package with which to run the Guix Build Coordinator.
35238 @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
35239 Service type for a Guix Build Coordinator agent. Its value must be a
35240 @code{guix-build-coordinator-agent-configuration} object.
35243 @deftp {Data Type} guix-build-coordinator-agent-configuration
35244 Data type representing the configuration a Guix Build Coordinator agent.
35247 @item @code{package} (default: @code{guix-build-coordinator/agent-only})
35248 The Guix Build Coordinator package to use.
35250 @item @code{user} (default: @code{"guix-build-coordinator-agent"})
35251 The system user to run the service as.
35253 @item @code{coordinator} (default: @code{"http://localhost:8745"})
35254 The URI to use when connecting to the coordinator.
35256 @item @code{authentication}
35257 Record describing how this agent should authenticate with the
35258 coordinator. Possible record types are described below.
35260 @item @code{systems} (default: @code{#f})
35261 The systems for which this agent should fetch builds. The agent process
35262 will use the current system it's running on as the default.
35264 @item @code{max-parallel-builds} (default: @code{1})
35265 The number of builds to perform in parallel.
35267 @item @code{max-1min-load-average} (default: @code{#f})
35268 Load average value to look at when considering starting new builds, if
35269 the 1 minute load average exceeds this value, the agent will wait before
35270 starting new builds.
35272 This will be unspecified if the value is @code{#f}, and the agent will
35273 use the number of cores reported by the system as the max 1 minute load
35276 @item @code{derivation-substitute-urls} (default: @code{#f})
35277 URLs from which to attempt to fetch substitutes for derivations, if the
35278 derivations aren't already available.
35280 @item @code{non-derivation-substitute-urls} (default: @code{#f})
35281 URLs from which to attempt to fetch substitutes for build inputs, if the
35282 input store items aren't already available.
35287 @deftp {Data Type} guix-build-coordinator-agent-password-auth
35288 Data type representing an agent authenticating with a coordinator via a
35293 The UUID of the agent. This should be generated by the coordinator
35294 process, stored in the coordinator database, and used by the intended
35297 @item @code{password}
35298 The password to use when connecting to the coordinator.
35303 @deftp {Data Type} guix-build-coordinator-agent-password-file-auth
35304 Data type representing an agent authenticating with a coordinator via a
35305 UUID and password read from a file.
35309 The UUID of the agent. This should be generated by the coordinator
35310 process, stored in the coordinator database, and used by the intended
35313 @item @code{password-file}
35314 A file containing the password to use when connecting to the
35320 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth
35321 Data type representing an agent authenticating with a coordinator via a
35322 dynamic auth token and agent name.
35325 @item @code{agent-name}
35326 Name of an agent, this is used to match up to an existing entry in the
35327 database if there is one. When no existing entry is found, a new entry
35328 is automatically added.
35331 Dynamic auth token, this is created and stored in the coordinator
35332 database, and is used by the agent to authenticate.
35337 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth-with-file
35338 Data type representing an agent authenticating with a coordinator via a
35339 dynamic auth token read from a file and agent name.
35342 @item @code{agent-name}
35343 Name of an agent, this is used to match up to an existing entry in the
35344 database if there is one. When no existing entry is found, a new entry
35345 is automatically added.
35347 @item @code{token-file}
35348 File containing the dynamic auth token, this is created and stored in
35349 the coordinator database, and is used by the agent to authenticate.
35354 The Guix Build Coordinator package contains a script to query an
35355 instance of the Guix Data Service for derivations to build, and then
35356 submit builds for those derivations to the coordinator. The service
35357 type below assists in running this script. This is an additional tool
35358 that may be useful when building derivations contained within an
35359 instance of the Guix Data Service.
35361 @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
35362 Service type for the
35363 guix-build-coordinator-queue-builds-from-guix-data-service script. Its
35364 value must be a @code{guix-build-coordinator-queue-builds-configuration}
35368 @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
35369 Data type representing the options to the queue builds from guix data
35373 @item @code{package} (default: @code{guix-build-coordinator})
35374 The Guix Build Coordinator package to use.
35376 @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
35377 The system user to run the service as.
35379 @item @code{coordinator} (default: @code{"http://localhost:8746"})
35380 The URI to use when connecting to the coordinator.
35382 @item @code{systems} (default: @code{#f})
35383 The systems for which to fetch derivations to build.
35385 @item @code{systems-and-targets} (default: @code{#f})
35386 An association list of system and target pairs for which to fetch
35387 derivations to build.
35389 @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
35390 The Guix Data Service instance from which to query to find out about
35391 derivations to build.
35393 @item @code{guix-data-service-build-server-id} (default: @code{#f})
35394 The Guix Data Service build server ID corresponding to the builds being
35395 submitted. Providing this speeds up the submitting of builds as
35396 derivations that have already been submitted can be skipped before
35397 asking the coordinator to build them.
35399 @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
35400 A file to record which commits have been processed, to avoid needlessly
35401 processing them again if the service is restarted.
35406 @subsubheading Guix Data Service
35407 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
35408 and provides data about GNU Guix. This includes information about
35409 packages, derivations and lint warnings.
35411 The data is stored in a PostgreSQL database, and available through a web
35414 @defvar {Scheme Variable} guix-data-service-type
35415 Service type for the Guix Data Service. Its value must be a
35416 @code{guix-data-service-configuration} object. The service optionally
35417 extends the getmail service, as the guix-commits mailing list is used to
35418 find out about changes in the Guix git repository.
35421 @deftp {Data Type} guix-data-service-configuration
35422 Data type representing the configuration of the Guix Data Service.
35425 @item @code{package} (default: @code{guix-data-service})
35426 The Guix Data Service package to use.
35428 @item @code{user} (default: @code{"guix-data-service"})
35429 The system user to run the service as.
35431 @item @code{group} (default: @code{"guix-data-service"})
35432 The system group to run the service as.
35434 @item @code{port} (default: @code{8765})
35435 The port to bind the web service to.
35437 @item @code{host} (default: @code{"127.0.0.1"})
35438 The host to bind the web service to.
35440 @item @code{getmail-idle-mailboxes} (default: @code{#f})
35441 If set, this is the list of mailboxes that the getmail service will be
35442 configured to listen to.
35444 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
35445 If set, this is the @code{getmail-retriever-configuration} object with
35446 which to configure getmail to fetch mail from the guix-commits mailing
35449 @item @code{extra-options} (default: @var{'()})
35450 Extra command line options for @code{guix-data-service}.
35452 @item @code{extra-process-jobs-options} (default: @var{'()})
35453 Extra command line options for @code{guix-data-service-process-jobs}.
35458 @subsubheading Nar Herder
35459 The @uref{https://git.cbaines.net/guix/nar-herder/about/,Nar Herder} is
35460 a utility for managing a collection of nars.
35462 @defvar {Scheme Variable} nar-herder-type
35463 Service type for the Guix Data Service. Its value must be a
35464 @code{nar-herder-configuration} object. The service optionally
35465 extends the getmail service, as the guix-commits mailing list is used to
35466 find out about changes in the Guix git repository.
35469 @deftp {Data Type} nar-herder-configuration
35470 Data type representing the configuration of the Guix Data Service.
35473 @item @code{package} (default: @code{nar-herder})
35474 The Nar Herder package to use.
35476 @item @code{user} (default: @code{"nar-herder"})
35477 The system user to run the service as.
35479 @item @code{group} (default: @code{"nar-herder"})
35480 The system group to run the service as.
35482 @item @code{port} (default: @code{8734})
35483 The port to bind the server to.
35485 @item @code{host} (default: @code{"127.0.0.1"})
35486 The host to bind the server to.
35488 @item @code{mirror} (default: @code{#f})
35489 Optional URL of the other Nar Herder instance which should be mirrored.
35490 This means that this Nar Herder instance will download it's database,
35491 and keep it up to date.
35493 @item @code{database} (default: @code{"/var/lib/nar-herder/nar_herder.db"})
35494 Location for the database. If this Nar Herder instance is mirroring
35495 another, the database will be downloaded if it doesn't exist. If this
35496 Nar Herder instance isn't mirroring another, an empty database will be
35499 @item @code{database-dump} (default: @code{"/var/lib/nar-herder/nar_herder_dump.db"})
35500 Location of the database dump. This is created and regularly updated by
35501 taking a copy of the database. This is the version of the database that
35502 is available to download.
35504 @item @code{storage} (default: @code{#f})
35505 Optional location in which to store nars.
35507 @item @code{storage-limit} (default: @code{"none"})
35508 Limit in bytes for the nars stored in the storage location. This can
35509 also be set to ``none'' so that there is no limit.
35511 When the storage location exceeds this size, nars are removed according
35512 to the nar removal criteria.
35514 @item @code{storage-nar-removal-criteria} (default: @code{'()})
35515 Criteria used to remove nars from the storage location. These are used
35516 in conjunction with the storage limit.
35518 When the storage location exceeds the storage limit size, nars will be
35519 checked against the nar removal criteria and if any of the criteria
35520 match, they will be removed. This will continue until the storage
35521 location is below the storage limit size.
35523 Each criteria is specified by a string, then an equals sign, then
35524 another string. Currently, only one criteria is supported, checking if a
35525 nar is stored on another Nar Herder instance.
35527 @item @code{ttl} (default: @code{#f})
35528 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
35529 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
35530 days, @code{1m} means 1 month, and so on.
35532 This allows the user's Guix to keep substitute information in cache for
35535 @item @code{negative-ttl} (default: @code{#f})
35536 Similarly produce @code{Cache-Control} HTTP headers to advertise the
35537 time-to-live (TTL) of @emph{negative} lookups---missing store items, for
35538 which the HTTP 404 code is returned. By default, no negative TTL is
35541 @item @code{log-level} (default: @code{'DEBUG})
35542 Log level to use, specify a log level like @code{'INFO} to stop logging
35543 individual requests.
35548 @node Linux Services
35549 @subsection Linux Services
35552 @cindex out of memory killer
35554 @cindex early out of memory daemon
35555 @subsubheading Early OOM Service
35557 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
35558 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
35559 space and provides a more responsive and configurable alternative to the
35560 in-kernel OOM killer. It is useful to prevent the system from becoming
35561 unresponsive when it runs out of memory.
35563 @deffn {Scheme Variable} earlyoom-service-type
35564 The service type for running @command{earlyoom}, the Early OOM daemon.
35565 Its value must be a @code{earlyoom-configuration} object, described
35566 below. The service can be instantiated in its default configuration
35570 (service earlyoom-service-type)
35574 @deftp {Data Type} earlyoom-configuration
35575 This is the configuration record for the @code{earlyoom-service-type}.
35578 @item @code{earlyoom} (default: @var{earlyoom})
35579 The Earlyoom package to use.
35581 @item @code{minimum-available-memory} (default: @code{10})
35582 The threshold for the minimum @emph{available} memory, in percentages.
35584 @item @code{minimum-free-swap} (default: @code{10})
35585 The threshold for the minimum free swap memory, in percentages.
35587 @item @code{prefer-regexp} (default: @code{#f})
35588 A regular expression (as a string) to match the names of the processes
35589 that should be preferably killed.
35591 @item @code{avoid-regexp} (default: @code{#f})
35592 A regular expression (as a string) to match the names of the processes
35593 that should @emph{not} be killed.
35595 @item @code{memory-report-interval} (default: @code{0})
35596 The interval in seconds at which a memory report is printed. It is
35597 disabled by default.
35599 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
35600 A boolean indicating whether the positive adjustments set in
35601 @file{/proc/*/oom_score_adj} should be ignored.
35603 @item @code{show-debug-messages?} (default: @code{#f})
35604 A boolean indicating whether debug messages should be printed. The logs
35605 are saved at @file{/var/log/earlyoom.log}.
35607 @item @code{send-notification-command} (default: @code{#f})
35608 This can be used to provide a custom command used for sending
35614 @cindex kernel module loader
35615 @subsubheading Kernel Module Loader Service
35617 The kernel module loader service allows one to load loadable kernel
35618 modules at boot. This is especially useful for modules that don't
35619 autoload and need to be manually loaded, as is the case with
35622 @deffn {Scheme Variable} kernel-module-loader-service-type
35623 The service type for loading loadable kernel modules at boot with
35624 @command{modprobe}. Its value must be a list of strings representing
35625 module names. For example loading the drivers provided by
35626 @code{ddcci-driver-linux}, in debugging mode by passing some module
35627 parameters, can be done as follow:
35630 (use-modules (gnu) (gnu services))
35631 (use-package-modules linux)
35632 (use-service-modules linux)
35634 (define ddcci-config
35635 (plain-file "ddcci.conf"
35636 "options ddcci dyndbg delay=120"))
35640 (services (cons* (service kernel-module-loader-service-type
35641 '("ddcci" "ddcci_backlight"))
35642 (simple-service 'ddcci-config etc-service-type
35643 (list `("modprobe.d/ddcci.conf"
35646 (kernel-loadable-modules (list ddcci-driver-linux)))
35651 @cindex Platform Reliability, Availability and Serviceability daemon
35652 @subsubheading Rasdaemon Service
35654 The Rasdaemon service provides a daemon which monitors platform
35655 @acronym{RAS, Reliability@comma{} Availability@comma{} and Serviceability} reports from
35656 Linux kernel trace events, logging them to syslogd.
35658 Reliability, Availability and Serviceability is a concept used on servers meant
35659 to measure their robustness.
35661 @strong{Relability} is the probability that a system will produce correct
35665 @item Generally measured as Mean Time Between Failures (MTBF), and
35666 @item Enhanced by features that help to avoid, detect and repair hardware
35670 @strong{Availability} is the probability that a system is operational at a
35674 @item Generally measured as a percentage of downtime per a period of time, and
35675 @item Often uses mechanisms to detect and correct hardware faults in runtime.
35678 @strong{Serviceability} is the simplicity and speed with which a system can be
35679 repaired or maintained:
35682 @item Generally measured on Mean Time Between Repair (MTBR).
35686 Among the monitoring measures, the most usual ones include:
35689 @item CPU – detect errors at instruction execution and at L1/L2/L3 caches;
35690 @item Memory – add error correction logic (ECC) to detect and correct errors;
35691 @item I/O – add CRC checksums for transferred data;
35692 @item Storage – RAID, journal file systems, checksums, Self-Monitoring,
35693 Analysis and Reporting Technology (SMART).
35696 By monitoring the number of occurrences of error detections, it is possible to
35697 identify if the probability of hardware errors is increasing, and, on such
35698 case, do a preventive maintenance to replace a degraded component while those
35699 errors are correctable.
35701 For detailed information about the types of error events gathered and how to
35702 make sense of them, see the kernel administrator's guide at
35703 @url{https://www.kernel.org/doc/html/latest/admin-guide/ras.html}.
35705 @defvr {Scheme Variable} rasdaemon-service-type
35706 Service type for the @command{rasdaemon} service. It accepts a
35707 @code{rasdaemon-configuration} object. Instantiating like
35710 (service rasdaemon-service-type)
35713 will load with a default configuration, which monitors all events and logs to
35717 @deftp {Data Type} rasdaemon-configuration
35718 The data type representing the configuration of @command{rasdaemon}.
35721 @item @code{record?} (default: @code{#f})
35723 A boolean indicating whether to record the events in an SQLite database. This
35724 provides a more structured access to the information contained in the log file.
35725 The database location is hard-coded to @file{/var/lib/rasdaemon/ras-mc_event.db}.
35731 @cindex compressed swap
35732 @cindex Compressed RAM-based block devices
35733 @subsubheading Zram Device Service
35735 The Zram device service provides a compressed swap device in system
35736 memory. The Linux Kernel documentation has more information about
35737 @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
35740 @deffn {Scheme Variable} zram-device-service-type
35741 This service creates the zram block device, formats it as swap and
35742 enables it as a swap device. The service's value is a
35743 @code{zram-device-configuration} record.
35745 @deftp {Data Type} zram-device-configuration
35746 This is the data type representing the configuration for the zram-device
35750 @item @code{size} (default @code{"1G"})
35751 This is the amount of space you wish to provide for the zram device. It
35752 accepts a string and can be a number of bytes or use a suffix, eg.:
35753 @code{"512M"} or @code{1024000}.
35754 @item @code{compression-algorithm} (default @code{'lzo})
35755 This is the compression algorithm you wish to use. It is difficult to
35756 list all the possible compression options, but common ones supported by
35757 Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
35758 @item @code{memory-limit} (default @code{0})
35759 This is the maximum amount of memory which the zram device can use.
35760 Setting it to '0' disables the limit. While it is generally expected
35761 that compression will be 2:1, it is possible that uncompressable data
35762 can be written to swap and this is a method to limit how much memory can
35763 be used. It accepts a string and can be a number of bytes or use a
35764 suffix, eg.: @code{"2G"}.
35765 @item @code{priority} (default @code{#f})
35766 This is the priority of the swap device created from the zram device.
35767 @xref{Swap Space} for a description of swap priorities. You might want
35768 to set a specific priority for the zram device, otherwise it could end
35769 up not being used much for the reasons described there.
35775 @node Hurd Services
35776 @subsection Hurd Services
35778 @defvr {Scheme Variable} hurd-console-service-type
35779 This service starts the fancy @code{VGA} console client on the Hurd.
35781 The service's value is a @code{hurd-console-configuration} record.
35784 @deftp {Data Type} hurd-console-configuration
35785 This is the data type representing the configuration for the
35786 hurd-console-service.
35789 @item @code{hurd} (default: @var{hurd})
35790 The Hurd package to use.
35794 @defvr {Scheme Variable} hurd-getty-service-type
35795 This service starts a tty using the Hurd @code{getty} program.
35797 The service's value is a @code{hurd-getty-configuration} record.
35800 @deftp {Data Type} hurd-getty-configuration
35801 This is the data type representing the configuration for the
35802 hurd-getty-service.
35805 @item @code{hurd} (default: @var{hurd})
35806 The Hurd package to use.
35809 The name of the console this Getty runs on---e.g., @code{"tty1"}.
35811 @item @code{baud-rate} (default: @code{38400})
35812 An integer specifying the baud rate of the tty.
35817 @node Miscellaneous Services
35818 @subsection Miscellaneous Services
35820 @cindex fingerprint
35821 @subsubheading Fingerprint Service
35823 The @code{(gnu services authentication)} module provides a DBus service to
35824 read and identify fingerprints via a fingerprint sensor.
35826 @defvr {Scheme Variable} fprintd-service-type
35827 The service type for @command{fprintd}, which provides the fingerprint
35828 reading capability.
35831 (service fprintd-service-type)
35836 @subsubheading System Control Service
35838 The @code{(gnu services sysctl)} provides a service to configure kernel
35839 parameters at boot.
35841 @defvr {Scheme Variable} sysctl-service-type
35842 The service type for @command{sysctl}, which modifies kernel parameters
35843 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
35847 (service sysctl-service-type
35848 (sysctl-configuration
35849 (settings '(("net.ipv4.ip_forward" . "1")))))
35852 Since @code{sysctl-service-type} is used in the default lists of
35853 services, @code{%base-services} and @code{%desktop-services}, you can
35854 use @code{modify-services} to change its configuration and add the
35855 kernel parameters that you want (@pxref{Service Reference,
35856 @code{modify-services}}).
35859 (modify-services %base-services
35860 (sysctl-service-type config =>
35861 (sysctl-configuration
35862 (settings (append '(("net.ipv4.ip_forward" . "1"))
35863 %default-sysctl-settings)))))
35868 @deftp {Data Type} sysctl-configuration
35869 The data type representing the configuration of @command{sysctl}.
35872 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
35873 The @command{sysctl} executable to use.
35875 @item @code{settings} (default: @code{%default-sysctl-settings})
35876 An association list specifies kernel parameters and their values.
35880 @defvr {Scheme Variable} %default-sysctl-settings
35881 An association list specifying the default @command{sysctl} parameters
35886 @subsubheading PC/SC Smart Card Daemon Service
35888 The @code{(gnu services security-token)} module provides the following service
35889 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
35890 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
35891 manager that coordinates communications with smart card readers, smart cards
35892 and cryptographic tokens that are connected to the system.
35894 @defvr {Scheme Variable} pcscd-service-type
35895 Service type for the @command{pcscd} service. Its value must be a
35896 @code{pcscd-configuration} object. To run pcscd in the default
35897 configuration, instantiate it as:
35900 (service pcscd-service-type)
35904 @deftp {Data Type} pcscd-configuration
35905 The data type representing the configuration of @command{pcscd}.
35908 @item @code{pcsc-lite} (default: @code{pcsc-lite})
35909 The pcsc-lite package that provides pcscd.
35910 @item @code{usb-drivers} (default: @code{(list ccid)})
35911 List of packages that provide USB drivers to pcscd. Drivers are expected to be
35912 under @file{pcsc/drivers} in the store directory of the package.
35917 @subsubheading Lirc Service
35919 The @code{(gnu services lirc)} module provides the following service.
35921 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
35922 [#:device #f] [#:driver #f] [#:config-file #f] @
35923 [#:extra-options '()]
35924 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
35925 decodes infrared signals from remote controls.
35927 Optionally, @var{device}, @var{driver} and @var{config-file}
35928 (configuration file name) may be specified. See @command{lircd} manual
35931 Finally, @var{extra-options} is a list of additional command-line options
35932 passed to @command{lircd}.
35936 @subsubheading Spice Service
35938 The @code{(gnu services spice)} module provides the following service.
35940 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
35941 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
35942 that enables sharing the clipboard with a vm and setting the guest display
35943 resolution when the graphical console window resizes.
35946 @cindex inputattach
35947 @subsubheading inputattach Service
35949 @cindex tablet input, for Xorg
35950 @cindex touchscreen input, for Xorg
35951 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
35952 use input devices such as Wacom tablets, touchscreens, or joysticks with the
35953 Xorg display server.
35955 @deffn {Scheme Variable} inputattach-service-type
35956 Type of a service that runs @command{inputattach} on a device and
35957 dispatches events from it.
35960 @deftp {Data Type} inputattach-configuration
35962 @item @code{device-type} (default: @code{"wacom"})
35963 The type of device to connect to. Run @command{inputattach --help}, from the
35964 @code{inputattach} package, to see the list of supported device types.
35966 @item @code{device} (default: @code{"/dev/ttyS0"})
35967 The device file to connect to the device.
35969 @item @code{baud-rate} (default: @code{#f})
35970 Baud rate to use for the serial connection.
35971 Should be a number or @code{#f}.
35973 @item @code{log-file} (default: @code{#f})
35974 If true, this must be the name of a file to log messages to.
35978 @subsubheading Dictionary Service
35980 The @code{(gnu services dict)} module provides the following service:
35982 @defvr {Scheme Variable} dicod-service-type
35983 This is the type of the service that runs the @command{dicod} daemon, an
35984 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
35987 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
35988 Return a service that runs the @command{dicod} daemon, an implementation
35989 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
35991 The optional @var{config} argument specifies the configuration for
35992 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
35993 default it serves the GNU Collaborative International Dictionary of English.
35995 You can add @command{open localhost} to your @file{~/.dico} file to make
35996 @code{localhost} the default server for @command{dico} client
35997 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
36000 @deftp {Data Type} dicod-configuration
36001 Data type representing the configuration of dicod.
36004 @item @code{dico} (default: @var{dico})
36005 Package object of the GNU Dico dictionary server.
36007 @item @code{interfaces} (default: @var{'("localhost")})
36008 This is the list of IP addresses and ports and possibly socket file
36009 names to listen to (@pxref{Server Settings, @code{listen} directive,,
36010 dico, GNU Dico Manual}).
36012 @item @code{handlers} (default: @var{'()})
36013 List of @code{<dicod-handler>} objects denoting handlers (module instances).
36015 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
36016 List of @code{<dicod-database>} objects denoting dictionaries to be served.
36020 @deftp {Data Type} dicod-handler
36021 Data type representing a dictionary handler (module instance).
36025 Name of the handler (module instance).
36027 @item @code{module} (default: @var{#f})
36028 Name of the dicod module of the handler (instance). If it is @code{#f},
36029 the module has the same name as the handler.
36030 (@pxref{Modules,,, dico, GNU Dico Manual}).
36032 @item @code{options}
36033 List of strings or gexps representing the arguments for the module handler
36037 @deftp {Data Type} dicod-database
36038 Data type representing a dictionary database.
36042 Name of the database, will be used in DICT commands.
36044 @item @code{handler}
36045 Name of the dicod handler (module instance) used by this database
36046 (@pxref{Handlers,,, dico, GNU Dico Manual}).
36048 @item @code{complex?} (default: @var{#f})
36049 Whether the database configuration complex. The complex configuration
36050 will need a corresponding @code{<dicod-handler>} object, otherwise not.
36052 @item @code{options}
36053 List of strings or gexps representing the arguments for the database
36054 (@pxref{Databases,,, dico, GNU Dico Manual}).
36058 @defvr {Scheme Variable} %dicod-database:gcide
36059 A @code{<dicod-database>} object serving the GNU Collaborative International
36060 Dictionary of English using the @code{gcide} package.
36063 The following is an example @code{dicod-service} configuration.
36066 (dicod-service #:config
36067 (dicod-configuration
36068 (handlers (list (dicod-handler
36072 (list #~(string-append "dbdir=" #$wordnet))))))
36073 (databases (list (dicod-database
36076 (handler "wordnet")
36077 (options '("database=wn")))
36078 %dicod-database:gcide))))
36082 @subsubheading Docker Service
36084 The @code{(gnu services docker)} module provides the following services.
36086 @defvr {Scheme Variable} docker-service-type
36088 This is the type of the service that runs @url{https://www.docker.com,Docker},
36089 a daemon that can execute application bundles (sometimes referred to as
36090 ``containers'') in isolated environments.
36094 @deftp {Data Type} docker-configuration
36095 This is the data type representing the configuration of Docker and Containerd.
36099 @item @code{docker} (default: @code{docker})
36100 The Docker daemon package to use.
36102 @item @code{docker-cli} (default: @code{docker-cli})
36103 The Docker client package to use.
36105 @item @code{containerd} (default: @var{containerd})
36106 The Containerd package to use.
36108 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
36109 The Docker user-land networking proxy package to use.
36111 @item @code{enable-proxy?} (default @code{#t})
36112 Enable or disable the use of the Docker user-land networking proxy.
36114 @item @code{debug?} (default @code{#f})
36115 Enable or disable debug output.
36117 @item @code{enable-iptables?} (default @code{#t})
36118 Enable or disable the addition of iptables rules.
36120 @item @code{environment-variables} (default: @code{()})
36121 List of environment variables to set for @command{dockerd}.
36123 This must be a list of strings where each string has the form
36124 @samp{@var{key}=@var{value}} as in this example:
36127 (list "LANGUAGE=eo:ca:eu"
36128 "TMPDIR=/tmp/dockerd")
36134 @cindex Singularity, container service
36135 @defvr {Scheme Variable} singularity-service-type
36136 This is the type of the service that allows you to run
36137 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
36138 create and run application bundles (aka. ``containers''). The value for this
36139 service is the Singularity package to use.
36141 The service does not install a daemon; instead, it installs helper programs as
36142 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
36143 @command{singularity run} and similar commands.
36147 @subsubheading Auditd Service
36149 The @code{(gnu services auditd)} module provides the following service.
36151 @defvr {Scheme Variable} auditd-service-type
36153 This is the type of the service that runs
36154 @url{https://people.redhat.com/sgrubb/audit/,auditd},
36155 a daemon that tracks security-relevant information on your system.
36157 Examples of things that can be tracked:
36167 Failed login attempts
36174 @command{auditctl} from the @code{audit} package can be used in order
36175 to add or remove events to be tracked (until the next reboot).
36176 In order to permanently track events, put the command line arguments
36177 of auditctl into a file called @code{audit.rules} in the configuration
36178 directory (see below).
36179 @command{aureport} from the @code{audit} package can be used in order
36180 to view a report of all recorded events.
36181 The audit daemon by default logs into the file
36182 @file{/var/log/audit.log}.
36186 @deftp {Data Type} auditd-configuration
36187 This is the data type representing the configuration of auditd.
36191 @item @code{audit} (default: @code{audit})
36192 The audit package to use.
36194 @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
36195 The directory containing the configuration file for the audit package, which
36196 must be named @code{auditd.conf}, and optionally some audit rules to
36197 instantiate on startup.
36203 @subsubheading R-Shiny service
36205 The @code{(gnu services science)} module provides the following service.
36207 @defvr {Scheme Variable} rshiny-service-type
36209 This is a type of service which is used to run a webapp created with
36210 @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
36211 variable and runs the provided script to call @code{runApp}.
36213 @deftp {Data Type} rshiny-configuration
36214 This is the data type representing the configuration of rshiny.
36218 @item @code{package} (default: @code{r-shiny})
36219 The package to use.
36221 @item @code{binary} (defaunlt @code{"rshiny"})
36222 The name of the binary or shell script located at @code{package/bin/} to
36223 run when the service is run.
36225 The common way to create this file is as follows:
36229 (let* ((out (assoc-ref %outputs "out"))
36230 (targetdir (string-append out "/share/" ,name))
36231 (app (string-append out "/bin/" ,name))
36232 (Rbin (search-input-file %build-inputs "/bin/Rscript")))
36234 (mkdir-p (string-append out "/bin"))
36235 (call-with-output-file app
36241 runApp(launch.browser=0, port=4202)~%\n"
36250 @subsubheading Nix service
36252 The @code{(gnu services nix)} module provides the following service.
36254 @defvr {Scheme Variable} nix-service-type
36256 This is the type of the service that runs build daemon of the
36257 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
36261 (use-modules (gnu))
36262 (use-service-modules nix)
36263 (use-package-modules package-management)
36267 (packages (append (list nix)
36270 (services (append (list (service nix-service-type))
36274 After @command{guix system reconfigure} configure Nix for your user:
36277 @item Add a Nix channel and update it. See
36278 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
36280 @item Create a symlink to your profile and activate Nix profile:
36284 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
36285 $ source /run/current-system/profile/etc/profile.d/nix.sh
36290 @deftp {Data Type} nix-configuration
36291 This data type represents the configuration of the Nix daemon.
36294 @item @code{nix} (default: @code{nix})
36295 The Nix package to use.
36297 @item @code{sandbox} (default: @code{#t})
36298 Specifies whether builds are sandboxed by default.
36300 @item @code{build-sandbox-items} (default: @code{'()})
36301 This is a list of strings or objects appended to the
36302 @code{build-sandbox-items} field of the configuration file.
36304 @item @code{extra-config} (default: @code{'()})
36305 This is a list of strings or objects appended to the configuration file.
36306 It is used to pass extra text to be added verbatim to the configuration
36309 @item @code{extra-options} (default: @code{'()})
36310 Extra command line options for @code{nix-service-type}.
36314 @node Setuid Programs
36315 @section Setuid Programs
36317 @cindex setuid programs
36318 @cindex setgid programs
36319 Some programs need to run with elevated privileges, even when they are
36320 launched by unprivileged users. A notorious example is the
36321 @command{passwd} program, which users can run to change their
36322 password, and which needs to access the @file{/etc/passwd} and
36323 @file{/etc/shadow} files---something normally restricted to root, for
36324 obvious security reasons. To address that, @command{passwd} should be
36325 @dfn{setuid-root}, meaning that it always runs with root privileges
36326 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
36327 for more info about the setuid mechanism).
36329 The store itself @emph{cannot} contain setuid programs: that would be a
36330 security issue since any user on the system can write derivations that
36331 populate the store (@pxref{The Store}). Thus, a different mechanism is
36332 used: instead of changing the setuid or setgid bits directly on files that
36333 are in the store, we let the system administrator @emph{declare} which
36334 programs should be entrusted with these additional privileges.
36336 The @code{setuid-programs} field of an @code{operating-system}
36337 declaration contains a list of @code{<setuid-program>} denoting the
36338 names of programs to have a setuid or setgid bit set (@pxref{Using the
36339 Configuration System}). For instance, the @command{mount.nfs} program,
36340 which is part of the nfs-utils package, with a setuid root can be
36341 designated like this:
36345 (program (file-append nfs-utils "/sbin/mount.nfs")))
36348 And then, to make @command{mount.nfs} setuid on your system, add the
36349 previous example to your operating system declaration by appending it to
36350 @code{%setuid-programs} like this:
36354 ;; Some fields omitted...
36356 (append (list (setuid-program
36357 (program (file-append nfs-utils "/sbin/mount.nfs"))))
36358 %setuid-programs)))
36361 @deftp {Data Type} setuid-program
36362 This data type represents a program with a setuid or setgid bit set.
36365 @item @code{program}
36366 A file-like object having its setuid and/or setgid bit set.
36368 @item @code{setuid?} (default: @code{#t})
36369 Whether to set user setuid bit.
36371 @item @code{setgid?} (default: @code{#f})
36372 Whether to set group setgid bit.
36374 @item @code{user} (default: @code{0})
36375 UID (integer) or user name (string) for the user owner of the program,
36378 @item @code{group} (default: @code{0})
36379 GID (integer) goup name (string) for the group owner of the program,
36385 A default set of setuid programs is defined by the
36386 @code{%setuid-programs} variable of the @code{(gnu system)} module.
36388 @defvr {Scheme Variable} %setuid-programs
36389 A list of @code{<setuid-program>} denoting common programs that are
36392 The list includes commands such as @command{passwd}, @command{ping},
36393 @command{su}, and @command{sudo}.
36396 Under the hood, the actual setuid programs are created in the
36397 @file{/run/setuid-programs} directory at system activation time. The
36398 files in this directory refer to the ``real'' binaries, which are in the
36401 @node X.509 Certificates
36402 @section X.509 Certificates
36404 @cindex HTTPS, certificates
36405 @cindex X.509 certificates
36407 Web servers available over HTTPS (that is, HTTP over the transport-layer
36408 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
36409 that the client can then use to @emph{authenticate} the server. To do
36410 that, clients verify that the server's certificate is signed by a
36411 so-called @dfn{certificate authority} (CA). But to verify the CA's
36412 signature, clients must have first acquired the CA's certificate.
36414 Web browsers such as GNU@tie{}IceCat include their own set of CA
36415 certificates, such that they are able to verify CA signatures
36418 However, most other programs that can talk HTTPS---@command{wget},
36419 @command{git}, @command{w3m}, etc.---need to be told where CA
36420 certificates can be found.
36422 @cindex @code{nss-certs}
36423 In Guix, this is done by adding a package that provides certificates
36424 to the @code{packages} field of the @code{operating-system} declaration
36425 (@pxref{operating-system Reference}). Guix includes one such package,
36426 @code{nss-certs}, which is a set of CA certificates provided as part of
36427 Mozilla's Network Security Services.
36429 Note that it is @emph{not} part of @code{%base-packages}, so you need to
36430 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
36431 most applications and libraries look for certificates by default, points
36432 to the certificates installed globally.
36434 Unprivileged users, including users of Guix on a foreign distro,
36435 can also install their own certificate package in
36436 their profile. A number of environment variables need to be defined so
36437 that applications and libraries know where to find them. Namely, the
36438 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
36439 variables. Some applications add their own environment variables; for
36440 instance, the Git version control system honors the certificate bundle
36441 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
36442 would typically run something like:
36445 guix install nss-certs
36446 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
36447 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
36448 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
36451 As another example, R requires the @env{CURL_CA_BUNDLE} environment
36452 variable to point to a certificate bundle, so you would have to run
36453 something like this:
36456 guix install nss-certs
36457 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
36460 For other applications you may want to look up the required environment
36461 variable in the relevant documentation.
36464 @node Name Service Switch
36465 @section Name Service Switch
36467 @cindex name service switch
36469 The @code{(gnu system nss)} module provides bindings to the
36470 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
36471 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
36472 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
36473 extended with new ``name'' lookup methods for system databases, which
36474 includes host names, service names, user accounts, and more (@pxref{Name
36475 Service Switch, System Databases and Name Service Switch,, libc, The GNU
36476 C Library Reference Manual}).
36478 The NSS configuration specifies, for each system database, which lookup
36479 method is to be used, and how the various methods are chained
36480 together---for instance, under which circumstances NSS should try the
36481 next method in the list. The NSS configuration is given in the
36482 @code{name-service-switch} field of @code{operating-system} declarations
36483 (@pxref{operating-system Reference, @code{name-service-switch}}).
36486 @cindex .local, host name lookup
36487 As an example, the declaration below configures the NSS to use the
36488 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
36489 back-end}, which supports host name lookups over multicast DNS (mDNS)
36490 for host names ending in @code{.local}:
36493 (name-service-switch
36494 (hosts (list %files ;first, check /etc/hosts
36496 ;; If the above did not succeed, try
36497 ;; with 'mdns_minimal'.
36499 (name "mdns_minimal")
36501 ;; 'mdns_minimal' is authoritative for
36502 ;; '.local'. When it returns "not found",
36503 ;; no need to try the next methods.
36504 (reaction (lookup-specification
36505 (not-found => return))))
36507 ;; Then fall back to DNS.
36511 ;; Finally, try with the "full" 'mdns'.
36516 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
36517 contains this configuration, so you will not have to type it if all you
36518 want is to have @code{.local} host lookup working.
36520 Note that, in this case, in addition to setting the
36521 @code{name-service-switch} of the @code{operating-system} declaration,
36522 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
36523 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
36524 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
36525 to the name service cache daemon (@pxref{Base Services,
36526 @code{nscd-service}}).
36528 For convenience, the following variables provide typical NSS
36531 @defvr {Scheme Variable} %default-nss
36532 This is the default name service switch configuration, a
36533 @code{name-service-switch} object.
36536 @defvr {Scheme Variable} %mdns-host-lookup-nss
36537 This is the name service switch configuration with support for host name
36538 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
36541 The reference for name service switch configuration is given below. It
36542 is a direct mapping of the configuration file format of the C library , so
36543 please refer to the C library manual for more information (@pxref{NSS
36544 Configuration File,,, libc, The GNU C Library Reference Manual}).
36545 Compared to the configuration file format of libc NSS, it has the advantage
36546 not only of adding this warm parenthetic feel that we like, but also
36547 static checks: you will know about syntax errors and typos as soon as you
36548 run @command{guix system}.
36550 @deftp {Data Type} name-service-switch
36552 This is the data type representation the configuration of libc's name
36553 service switch (NSS). Each field below represents one of the supported
36570 The system databases handled by the NSS@. Each of these fields must be a
36571 list of @code{<name-service>} objects (see below).
36575 @deftp {Data Type} name-service
36577 This is the data type representing an actual name service and the
36578 associated lookup action.
36582 A string denoting the name service (@pxref{Services in the NSS
36583 configuration,,, libc, The GNU C Library Reference Manual}).
36585 Note that name services listed here must be visible to nscd. This is
36586 achieved by passing the @code{#:name-services} argument to
36587 @code{nscd-service} the list of packages providing the needed name
36588 services (@pxref{Base Services, @code{nscd-service}}).
36591 An action specified using the @code{lookup-specification} macro
36592 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
36593 Reference Manual}). For example:
36596 (lookup-specification (unavailable => continue)
36597 (success => return))
36602 @node Initial RAM Disk
36603 @section Initial RAM Disk
36606 @cindex initial RAM disk
36607 For bootstrapping purposes, the Linux-Libre kernel is passed an
36608 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
36609 root file system as well as an initialization script. The latter is
36610 responsible for mounting the real root file system, and for loading any
36611 kernel modules that may be needed to achieve that.
36613 The @code{initrd-modules} field of an @code{operating-system}
36614 declaration allows you to specify Linux-libre kernel modules that must
36615 be available in the initrd. In particular, this is where you would list
36616 modules needed to actually drive the hard disk where your root partition
36617 is---although the default value of @code{initrd-modules} should cover
36618 most use cases. For example, assuming you need the @code{megaraid_sas}
36619 module in addition to the default modules to be able to access your root
36620 file system, you would write:
36625 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
36628 @defvr {Scheme Variable} %base-initrd-modules
36629 This is the list of kernel modules included in the initrd by default.
36632 Furthermore, if you need lower-level customization, the @code{initrd}
36633 field of an @code{operating-system} declaration allows
36634 you to specify which initrd you would like to use. The @code{(gnu
36635 system linux-initrd)} module provides three ways to build an initrd: the
36636 high-level @code{base-initrd} procedure and the low-level
36637 @code{raw-initrd} and @code{expression->initrd} procedures.
36639 The @code{base-initrd} procedure is intended to cover most common uses.
36640 For example, if you want to add a bunch of kernel modules to be loaded
36641 at boot time, you can define the @code{initrd} field of the operating
36642 system declaration like this:
36645 (initrd (lambda (file-systems . rest)
36646 ;; Create a standard initrd but set up networking
36647 ;; with the parameters QEMU expects by default.
36648 (apply base-initrd file-systems
36649 #:qemu-networking? #t
36653 The @code{base-initrd} procedure also handles common use cases that
36654 involves using the system as a QEMU guest, or as a ``live'' system with
36655 volatile root file system.
36657 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
36658 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
36659 such as trying to guess which kernel modules and packages should be included
36660 to the initrd. An example use of @code{raw-initrd} is when a user has
36661 a custom Linux kernel configuration and default kernel modules included by
36662 @code{base-initrd} are not available.
36664 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
36665 honors several options passed on the Linux kernel command line
36666 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
36667 @code{-append} option of QEMU), notably:
36670 @item gnu.load=@var{boot}
36671 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
36672 program, once it has mounted the root file system.
36674 Guix uses this option to yield control to a boot program that runs the
36675 service activation programs and then spawns the GNU@tie{}Shepherd, the
36676 initialization system.
36678 @item root=@var{root}
36679 Mount @var{root} as the root file system. @var{root} can be a device
36680 name like @code{/dev/sda1}, a file system label, or a file system UUID.
36681 When unspecified, the device name from the root file system of the
36682 operating system declaration is used.
36684 @item rootfstype=@var{type}
36685 Set the type of the root file system. It overrides the @code{type}
36686 field of the root file system specified via the @code{operating-system}
36687 declaration, if any.
36689 @item rootflags=@var{options}
36690 Set the mount @emph{options} of the root file system. It overrides the
36691 @code{options} field of the root file system specified via the
36692 @code{operating-system} declaration, if any.
36694 @item fsck.mode=@var{mode}
36695 Whether to check the @var{root} file system for errors before mounting
36696 it. @var{mode} is one of @code{skip} (never check), @code{force} (always
36697 check), or @code{auto} to respect the root @code{<file-system>} object's
36698 @code{check?} setting (@pxref{File Systems}) and run a full scan only if
36699 the file system was not cleanly shut down.
36701 @code{auto} is the default if this option is not present or if @var{mode}
36702 is not one of the above.
36704 @item fsck.repair=@var{level}
36705 The level of repairs to perform automatically if errors are found in the
36706 @var{root} file system. @var{level} is one of @code{no} (do not write to
36707 @var{root} at all if possible), @code{yes} (repair as much as possible),
36708 or @code{preen} to repair problems considered safe to repair automatically.
36710 @code{preen} is the default if this option is not present or if @var{level}
36711 is not one of the above.
36713 @item gnu.system=@var{system}
36714 Have @file{/run/booted-system} and @file{/run/current-system} point to
36717 @item modprobe.blacklist=@var{modules}@dots{}
36718 @cindex module, black-listing
36719 @cindex black list, of kernel modules
36720 Instruct the initial RAM disk as well as the @command{modprobe} command
36721 (from the kmod package) to refuse to load @var{modules}. @var{modules}
36722 must be a comma-separated list of module names---e.g.,
36723 @code{usbkbd,9pnet}.
36726 Start a read-eval-print loop (REPL) from the initial RAM disk before it
36727 tries to load kernel modules and to mount the root file system. Our
36728 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
36729 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
36730 Manual}, for more information on Guile's REPL.
36734 Now that you know all the features that initial RAM disks produced by
36735 @code{base-initrd} and @code{raw-initrd} provide,
36736 here is how to use it and customize it further.
36739 @cindex initial RAM disk
36740 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
36741 [#:linux-modules '()] [#:mapped-devices '()] @
36742 [#:keyboard-layout #f] @
36743 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
36744 Return a derivation that builds a raw initrd. @var{file-systems} is
36745 a list of file systems to be mounted by the initrd, possibly in addition to
36746 the root file system specified on the kernel command line via @option{root}.
36747 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
36748 @var{mapped-devices} is a list of device mappings to realize before
36749 @var{file-systems} are mounted (@pxref{Mapped Devices}).
36750 @var{helper-packages} is a list of packages to be copied in the initrd.
36752 include @code{e2fsck/static} or other packages needed by the initrd to check
36753 the root file system.
36755 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
36756 the desired console keyboard layout. This is done before @var{mapped-devices}
36757 are set up and before @var{file-systems} are mounted such that, should the
36758 user need to enter a passphrase or use the REPL, this happens using the
36759 intended keyboard layout.
36761 When @var{qemu-networking?} is true, set up networking with the standard QEMU
36762 parameters. When @var{virtio?} is true, load additional modules so that the
36763 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
36765 When @var{volatile-root?} is true, the root file system is writable but any changes
36769 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
36770 [#:mapped-devices '()] [#:keyboard-layout #f] @
36771 [#:qemu-networking? #f] [#:volatile-root? #f] @
36772 [#:linux-modules '()]
36773 Return as a file-like object a generic initrd, with kernel
36774 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
36775 mounted by the initrd, possibly in addition to the root file system specified
36776 on the kernel command line via @option{root}. @var{mapped-devices} is a list of device
36777 mappings to realize before @var{file-systems} are mounted.
36779 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
36780 the desired console keyboard layout. This is done before @var{mapped-devices}
36781 are set up and before @var{file-systems} are mounted such that, should the
36782 user need to enter a passphrase or use the REPL, this happens using the
36783 intended keyboard layout.
36785 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
36787 The initrd is automatically populated with all the kernel modules necessary
36788 for @var{file-systems} and for the given options. Additional kernel
36789 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
36790 loaded at boot time in the order in which they appear.
36793 Needless to say, the initrds we produce and use embed a
36794 statically-linked Guile, and the initialization program is a Guile
36795 program. That gives a lot of flexibility. The
36796 @code{expression->initrd} procedure builds such an initrd, given the
36797 program to run in that initrd.
36799 @deffn {Scheme Procedure} expression->initrd @var{exp} @
36800 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
36801 Return as a file-like object a Linux initrd (a gzipped cpio archive)
36802 containing @var{guile} and that evaluates @var{exp}, a G-expression,
36803 upon booting. All the derivations referenced by @var{exp} are
36804 automatically copied to the initrd.
36807 @node Bootloader Configuration
36808 @section Bootloader Configuration
36811 @cindex boot loader
36813 The operating system supports multiple bootloaders. The bootloader is
36814 configured using @code{bootloader-configuration} declaration. All the
36815 fields of this structure are bootloader agnostic except for one field,
36816 @code{bootloader} that indicates the bootloader to be configured and
36819 Some of the bootloaders do not honor every field of
36820 @code{bootloader-configuration}. For instance, the extlinux
36821 bootloader does not support themes and thus ignores the @code{theme}
36824 @deftp {Data Type} bootloader-configuration
36825 The type of a bootloader configuration declaration.
36829 @item @code{bootloader}
36830 @cindex EFI, bootloader
36831 @cindex UEFI, bootloader
36832 @cindex BIOS, bootloader
36833 The bootloader to use, as a @code{bootloader} object. For now
36834 @code{grub-bootloader}, @code{grub-efi-bootloader},
36835 @code{grub-efi-netboot-bootloader}, @code{grub-efi-removable-bootloader},
36836 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
36838 @cindex ARM, bootloaders
36839 @cindex AArch64, bootloaders
36840 Available bootloaders are described in @code{(gnu bootloader @dots{})}
36841 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
36842 of bootloaders for a wide range of ARM and AArch64 systems, using the
36843 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
36845 @vindex grub-efi-bootloader
36846 @code{grub-efi-bootloader} allows to boot on modern systems using the
36847 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
36848 use if the installation image contains a @file{/sys/firmware/efi} directory
36849 when you boot it on your system.
36851 @vindex grub-bootloader
36852 @code{grub-bootloader} allows you to boot in particular Intel-based machines
36853 in ``legacy'' BIOS mode.
36855 @vindex grub-efi-netboot-bootloader
36856 @code{grub-efi-netboot-bootloader} allows you to boot your system over network
36857 through TFTP@. In combination with an NFS root file system this allows you to
36858 build a diskless Guix system.
36860 The installation of the @code{grub-efi-netboot-bootloader} generates the
36861 content of the TFTP root directory at @code{targets} (@pxref{Bootloader
36862 Configuration, @code{targets}}), to be served by a TFTP server. You may
36863 want to mount your TFTP server directories onto the @code{targets} to
36864 move the required files to the TFTP server automatically.
36866 If you plan to use an NFS root file system as well (actually if you mount the
36867 store from an NFS share), then the TFTP server needs to serve the file
36868 @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
36869 image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
36870 initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
36871 files from the store will be accessed by GRUB through TFTP with their normal
36872 store path, for example as
36873 @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
36875 Two symlinks are created to make this possible. For each target in the
36876 @code{targets} field, the first symlink is
36877 @samp{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
36878 @file{../../../boot/grub/grub.cfg}, where @samp{target} may be
36879 @file{/boot}. In this case the link is not leaving the served TFTP root
36880 directory, but otherwise it does. The second link is
36881 @samp{target}@file{/gnu/store} and points to @file{../gnu/store}. This
36882 link is leaving the served TFTP root directory.
36884 The assumption behind all this is that you have an NFS server exporting
36885 the root file system for your Guix system, and additionally a TFTP
36886 server exporting your @code{targets} directories—usually a single
36887 @file{/boot}—from that same root file system for your Guix system. In
36888 this constellation the symlinks will work.
36890 For other constellations you will have to program your own bootloader
36891 installer, which then takes care to make necessary files from the store
36892 accessible through TFTP, for example by copying them into the TFTP root
36893 directory to your @code{targets}.
36895 It is important to note that symlinks pointing outside the TFTP root directory
36896 may need to be allowed in the configuration of your TFTP server. Further the
36897 store link exposes the whole store through TFTP@. Both points need to be
36898 considered carefully for security aspects.
36900 Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
36901 NFS servers, you also need a properly configured DHCP server to make the booting
36902 over netboot possible. For all this we can currently only recommend you to look
36903 for instructions about @acronym{PXE, Preboot eXecution Environment}.
36905 @vindex grub-efi-removable-bootloader
36906 @code{grub-efi-removable-bootloader} allows you to boot your system from
36907 removable media by writing the GRUB file to the UEFI-specification location of
36908 @file{/EFI/BOOT/BOOTX64.efi} of the boot directory, usually @file{/boot/efi}.
36909 This is also useful for some UEFI firmwares that ``forget'' their configuration
36910 from their non-volatile storage. Like @code{grub-efi-bootloader}, this can only
36911 be used if the @file{/sys/firmware/efi} directory is available.
36914 This @emph{will} overwrite the GRUB file from any other operating systems that
36915 also place their GRUB file in the UEFI-specification location; making them
36919 @item @code{targets}
36920 This is a list of strings denoting the targets onto which to install the
36923 The interpretation of targets depends on the bootloader in question.
36924 For @code{grub-bootloader}, for example, they should be device names
36925 understood by the bootloader @command{installer} command, such as
36926 @code{/dev/sda} or @code{(hd0)} (@pxref{Invoking grub-install,,, grub,
36927 GNU GRUB Manual}). For @code{grub-efi-bootloader} and
36928 @code{grub-efi-removable-bootloader} they should be mount
36929 points of the EFI file system, usually @file{/boot/efi}. For
36930 @code{grub-efi-netboot-bootloader}, @code{targets} should be the mount
36931 points corresponding to TFTP root directories served by your TFTP
36934 @item @code{menu-entries} (default: @code{()})
36935 A possibly empty list of @code{menu-entry} objects (see below), denoting
36936 entries to appear in the bootloader menu, in addition to the current
36937 system entry and the entry pointing to previous system generations.
36939 @item @code{default-entry} (default: @code{0})
36940 The index of the default boot menu entry. Index 0 is for the entry of the
36943 @item @code{timeout} (default: @code{5})
36944 The number of seconds to wait for keyboard input before booting. Set to
36945 0 to boot immediately, and to -1 to wait indefinitely.
36947 @cindex keyboard layout, for the bootloader
36948 @item @code{keyboard-layout} (default: @code{#f})
36949 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
36950 layout, usually US@tie{}English (``qwerty'').
36952 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
36956 This option is currently ignored by bootloaders other than @code{grub} and
36960 @item @code{theme} (default: @var{#f})
36961 The bootloader theme object describing the theme to use. If no theme
36962 is provided, some bootloaders might use a default theme, that's true
36965 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
36966 The output terminals used for the bootloader boot menu, as a list of
36967 symbols. GRUB accepts the values: @code{console}, @code{serial},
36968 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
36969 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
36970 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
36971 configuration,,, grub,GNU GRUB manual}).
36973 @item @code{terminal-inputs} (default: @code{'()})
36974 The input terminals used for the bootloader boot menu, as a list of
36975 symbols. For GRUB, the default is the native platform terminal as
36976 determined at run-time. GRUB accepts the values: @code{console},
36977 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
36978 @code{usb_keyboard}. This field corresponds to the GRUB variable
36979 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
36982 @item @code{serial-unit} (default: @code{#f})
36983 The serial unit used by the bootloader, as an integer from 0 to 3.
36984 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
36985 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
36987 @item @code{serial-speed} (default: @code{#f})
36988 The speed of the serial interface, as an integer. For GRUB, the
36989 default value is chosen at run-time; currently GRUB chooses
36990 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
36997 Should you want to list additional boot menu entries @i{via} the
36998 @code{menu-entries} field above, you will need to create them with the
36999 @code{menu-entry} form. For example, imagine you want to be able to
37000 boot another distro (hard to imagine!), you can define a menu entry
37005 (label "The Other Distro")
37006 (linux "/boot/old/vmlinux-2.6.32")
37007 (linux-arguments '("root=/dev/sda2"))
37008 (initrd "/boot/old/initrd"))
37013 @deftp {Data Type} menu-entry
37014 The type of an entry in the bootloader menu.
37019 The label to show in the menu---e.g., @code{"GNU"}.
37021 @item @code{linux} (default: @code{#f})
37022 The Linux kernel image to boot, for example:
37025 (file-append linux-libre "/bzImage")
37028 For GRUB, it is also possible to specify a device explicitly in the
37029 file path using GRUB's device naming convention (@pxref{Naming
37030 convention,,, grub, GNU GRUB manual}), for example:
37033 "(hd0,msdos1)/boot/vmlinuz"
37036 If the device is specified explicitly as above, then the @code{device}
37037 field is ignored entirely.
37039 @item @code{linux-arguments} (default: @code{()})
37040 The list of extra Linux kernel command-line arguments---e.g.,
37041 @code{("console=ttyS0")}.
37043 @item @code{initrd} (default: @code{#f})
37044 A G-Expression or string denoting the file name of the initial RAM disk
37045 to use (@pxref{G-Expressions}).
37047 @item @code{device} (default: @code{#f})
37048 The device where the kernel and initrd are to be found---i.e., for GRUB,
37049 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
37051 This may be a file system label (a string), a file system UUID (a
37052 bytevector, @pxref{File Systems}), or @code{#f}, in which case
37053 the bootloader will search the device containing the file specified by
37054 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
37055 must @emph{not} be an OS device name such as @file{/dev/sda1}.
37057 @item @code{multiboot-kernel} (default: @code{#f})
37058 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
37059 manual}). When this field is set, a Multiboot menu-entry is generated.
37063 (file-append mach "/boot/gnumach")
37066 @item @code{multiboot-arguments} (default: @code{()})
37067 The list of extra command-line arguments for the multiboot-kernel.
37069 @item @code{multiboot-modules} (default: @code{()})
37070 The list of commands for loading Multiboot modules. For example:
37073 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
37075 (list (file-append libc "/lib/ld.so.1") "exec"
37085 @c FIXME: Write documentation once it's stable.
37086 For now only GRUB has theme support. GRUB themes are created using
37087 the @code{grub-theme} form, which is not fully documented yet.
37089 @deftp {Data Type} grub-theme
37090 Data type representing the configuration of the GRUB theme.
37093 @item @code{gfxmode} (default: @code{'("auto")})
37094 The GRUB @code{gfxmode} to set (a list of screen resolution strings,
37095 @pxref{gfxmode,,, grub, GNU GRUB manual}).
37099 @deffn {Scheme Procedure} grub-theme
37100 Return the default GRUB theme used by the operating system if no
37101 @code{theme} field is specified in @code{bootloader-configuration}
37104 It comes with a fancy background image displaying the GNU and Guix
37108 For example, to override the default resolution, you may use something
37113 (bootloader-configuration
37116 (inherit (grub-theme))
37117 (gfxmode '("1024x786x32" "auto"))))))
37120 @node Invoking guix system
37121 @section Invoking @code{guix system}
37123 Once you have written an operating system declaration as seen in the
37124 previous section, it can be @dfn{instantiated} using the @command{guix
37125 system} command. The synopsis is:
37128 guix system @var{options}@dots{} @var{action} @var{file}
37131 @var{file} must be the name of a file containing an
37132 @code{operating-system} declaration. @var{action} specifies how the
37133 operating system is instantiated. Currently the following values are
37138 Display available service type definitions that match the given regular
37139 expressions, sorted by relevance:
37145 $ guix system search console
37146 name: console-fonts
37147 location: gnu/services/base.scm:806:2
37148 extends: shepherd-root
37149 description: Install the given fonts on the specified ttys (fonts are per
37150 + virtual console on GNU/Linux). The value of this service is a list of
37151 + tty/font pairs. The font can be the name of a font provided by the `kbd'
37152 + package or any valid argument to `setfont', as in this example:
37154 + '(("tty1" . "LatGrkCyr-8x16")
37155 + ("tty2" . (file-append
37157 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
37158 + ("tty3" . (file-append
37160 + "/share/consolefonts/ter-132n"))) ; for HDPI
37164 location: gnu/services/base.scm:1190:2
37165 extends: shepherd-root
37166 description: Provide console login using the `mingetty' program.
37170 location: gnu/services/base.scm:860:2
37172 description: Provide a console log-in service as specified by its
37173 + configuration value, a `login-configuration' object.
37179 As for @command{guix package --search}, the result is written in
37180 @code{recutils} format, which makes it easy to filter the output
37181 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
37183 @cindex service type definition, editing
37184 @cindex editing, service type definition
37186 Edit or view the definition of the given service types.
37188 For example, the command below opens your editor, as specified by the
37189 @env{EDITOR} environment variable, on the definition of the
37190 @code{openssh} service type:
37193 guix system edit openssh
37197 Build the operating system described in @var{file}, activate it, and
37198 switch to it@footnote{This action (and the related actions
37199 @code{switch-generation} and @code{roll-back}) are usable only on
37200 systems already running Guix System.}.
37203 @c The paragraph below refers to the problem discussed at
37204 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
37205 It is highly recommended to run @command{guix pull} once before you run
37206 @command{guix system reconfigure} for the first time (@pxref{Invoking
37207 guix pull}). Failing to do that you would see an older version of Guix
37208 once @command{reconfigure} has completed.
37211 This effects all the configuration specified in @var{file}: user
37212 accounts, system services, global package list, setuid programs, etc.
37213 The command starts system services specified in @var{file} that are not
37214 currently running; if a service is currently running this command will
37215 arrange for it to be upgraded the next time it is stopped (e.g.@: by
37216 @code{herd stop X} or @code{herd restart X}).
37218 This command creates a new generation whose number is one greater than
37219 the current generation (as reported by @command{guix system
37220 list-generations}). If that generation already exists, it will be
37221 overwritten. This behavior mirrors that of @command{guix package}
37222 (@pxref{Invoking guix package}).
37224 It also adds a bootloader menu entry for the new OS configuration,
37225 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
37226 entries for older configurations to a submenu, allowing you to choose
37227 an older system generation at boot time should you need it.
37229 @cindex provenance tracking, of the operating system
37230 Upon completion, the new system is deployed under
37231 @file{/run/current-system}. This directory contains @dfn{provenance
37232 meta-data}: the list of channels in use (@pxref{Channels}) and
37233 @var{file} itself, when available. You can view it by running:
37236 guix system describe
37239 This information is useful should you later want to inspect how this
37240 particular generation was built. In fact, assuming @var{file} is
37241 self-contained, you can later rebuild generation @var{n} of your
37242 operating system with:
37245 guix time-machine \
37246 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
37247 system reconfigure \
37248 /var/guix/profiles/system-@var{n}-link/configuration.scm
37251 You can think of it as some sort of built-in version control! Your
37252 system is not just a binary artifact: @emph{it carries its own source}.
37253 @xref{Service Reference, @code{provenance-service-type}}, for more
37254 information on provenance tracking.
37256 By default, @command{reconfigure} @emph{prevents you from downgrading
37257 your system}, which could (re)introduce security vulnerabilities and
37258 also cause problems with ``stateful'' services such as database
37259 management systems. You can override that behavior by passing
37260 @option{--allow-downgrades}.
37262 @item switch-generation
37263 @cindex generations
37264 Switch to an existing system generation. This action atomically
37265 switches the system profile to the specified system generation. It
37266 also rearranges the system's existing bootloader menu entries. It
37267 makes the menu entry for the specified system generation the default,
37268 and it moves the entries for the other generations to a submenu, if
37269 supported by the bootloader being used. The next time the system
37270 boots, it will use the specified system generation.
37272 The bootloader itself is not being reinstalled when using this
37273 command. Thus, the installed bootloader is used with an updated
37274 configuration file.
37276 The target generation can be specified explicitly by its generation
37277 number. For example, the following invocation would switch to system
37281 guix system switch-generation 7
37284 The target generation can also be specified relative to the current
37285 generation with the form @code{+N} or @code{-N}, where @code{+3} means
37286 ``3 generations ahead of the current generation,'' and @code{-1} means
37287 ``1 generation prior to the current generation.'' When specifying a
37288 negative value such as @code{-1}, you must precede it with @code{--} to
37289 prevent it from being parsed as an option. For example:
37292 guix system switch-generation -- -1
37295 Currently, the effect of invoking this action is @emph{only} to switch
37296 the system profile to an existing generation and rearrange the
37297 bootloader menu entries. To actually start using the target system
37298 generation, you must reboot after running this action. In the future,
37299 it will be updated to do the same things as @command{reconfigure},
37300 like activating and deactivating services.
37302 This action will fail if the specified generation does not exist.
37305 @cindex rolling back
37306 Switch to the preceding system generation. The next time the system
37307 boots, it will use the preceding system generation. This is the inverse
37308 of @command{reconfigure}, and it is exactly the same as invoking
37309 @command{switch-generation} with an argument of @code{-1}.
37311 Currently, as with @command{switch-generation}, you must reboot after
37312 running this action to actually start using the preceding system
37315 @item delete-generations
37316 @cindex deleting system generations
37317 @cindex saving space
37318 Delete system generations, making them candidates for garbage collection
37319 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
37322 This works in the same way as @samp{guix package --delete-generations}
37323 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
37324 arguments, all system generations but the current one are deleted:
37327 guix system delete-generations
37330 You can also select the generations you want to delete. The example below
37331 deletes all the system generations that are more than two months old:
37334 guix system delete-generations 2m
37337 Running this command automatically reinstalls the bootloader with an updated
37338 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
37339 longer lists the generations that have been deleted.
37342 Build the derivation of the operating system, which includes all the
37343 configuration files and programs needed to boot and run the system.
37344 This action does not actually install anything.
37347 Populate the given directory with all the files necessary to run the
37348 operating system specified in @var{file}. This is useful for first-time
37349 installations of Guix System. For instance:
37352 guix system init my-os-config.scm /mnt
37355 copies to @file{/mnt} all the store items required by the configuration
37356 specified in @file{my-os-config.scm}. This includes configuration
37357 files, packages, and so on. It also creates other essential files
37358 needed for the system to operate correctly---e.g., the @file{/etc},
37359 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
37361 This command also installs bootloader on the targets specified in
37362 @file{my-os-config}, unless the @option{--no-bootloader} option was
37366 @cindex virtual machine
37368 @anchor{guix system vm}
37369 Build a virtual machine (VM) that contains the operating system declared
37370 in @var{file}, and return a script to run that VM.
37373 The @code{vm} action and others below
37374 can use KVM support in the Linux-libre kernel. Specifically, if the
37375 machine has hardware virtualization support, the corresponding
37376 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
37377 must exist and be readable and writable by the user and by the
37378 build users of the daemon (@pxref{Build Environment Setup}).
37381 Arguments given to the script are passed to QEMU as in the example
37382 below, which enables networking and requests 1@tie{}GiB of RAM for the
37386 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -nic user,model=virtio-net-pci
37389 It's possible to combine the two steps into one:
37392 $ $(guix system vm my-config.scm) -m 1024 -smp 2 -nic user,model=virtio-net-pci
37395 The VM shares its store with the host system.
37397 By default, the root file system of the VM is mounted volatile; the
37398 @option{--persistent} option can be provided to make it persistent
37399 instead. In that case, the VM disk-image file will be copied from the
37400 store to the @env{TMPDIR} directory to make it writable.
37402 Additional file systems can be shared between the host and the VM using
37403 the @option{--share} and @option{--expose} command-line options: the former
37404 specifies a directory to be shared with write access, while the latter
37405 provides read-only access to the shared directory.
37407 The example below creates a VM in which the user's home directory is
37408 accessible read-only, and where the @file{/exchange} directory is a
37409 read-write mapping of @file{$HOME/tmp} on the host:
37412 guix system vm my-config.scm \
37413 --expose=$HOME --share=$HOME/tmp=/exchange
37416 On GNU/Linux, the default is to boot directly to the kernel; this has
37417 the advantage of requiring only a very tiny root disk image since the
37418 store of the host can then be mounted.
37420 The @option{--full-boot} option forces a complete boot sequence, starting
37421 with the bootloader. This requires more disk space since a root image
37422 containing at least the kernel, initrd, and bootloader data files must
37425 The @option{--image-size} option can be used to specify the size of the
37428 The @option{--no-graphic} option will instruct @command{guix system} to
37429 spawn a headless VM that will use the invoking tty for IO. Among other
37430 things, this enables copy-pasting, and scrollback. Use the @kbd{ctrl-a}
37431 prefix to issue QEMU commands; e.g. @kbd{ctrl-a h} prints a help,
37432 @kbd{ctrl-a x} quits the VM, and @kbd{ctrl-a c} switches between the
37433 QEMU monitor and the VM.
37435 @cindex System images, creation in various formats
37436 @cindex Creating system images in various formats
37438 @cindex image, creating disk images
37439 The @code{image} command can produce various image types. The image
37440 type can be selected using the @option{--image-type} option. It
37441 defaults to @code{efi-raw}. When its value is @code{iso9660}, the
37442 @option{--label} option can be used to specify a volume ID with
37443 @code{image}. By default, the root file system of a disk image is
37444 mounted non-volatile; the @option{--volatile} option can be provided to
37445 make it volatile instead. When using @code{image}, the bootloader
37446 installed on the generated image is taken from the provided
37447 @code{operating-system} definition. The following example demonstrates
37448 how to generate an image that uses the @code{grub-efi-bootloader}
37449 bootloader and boot it with QEMU:
37452 image=$(guix system image --image-type=qcow2 \
37453 gnu/system/examples/lightweight-desktop.tmpl)
37454 cp $image /tmp/my-image.qcow2
37455 chmod +w /tmp/my-image.qcow2
37456 qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
37457 -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
37460 When using the @code{efi-raw} image type, a raw disk image is produced;
37461 it can be copied as is to a USB stick, for instance. Assuming
37462 @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
37463 the image to it using the following command:
37466 # dd if=$(guix system image my-os.scm) of=/dev/sdc status=progress
37469 The @code{--list-image-types} command lists all the available image
37472 @cindex creating virtual machine images
37473 When using the @code{qcow2} image type, the returned image is in qcow2
37474 format, which the QEMU emulator can efficiently use. @xref{Running Guix
37475 in a VM}, for more information on how to run the image in a virtual
37476 machine. The @code{grub-bootloader} bootloader is always used
37477 independently of what is declared in the @code{operating-system} file
37478 passed as argument. This is to make it easier to work with QEMU, which
37479 uses the SeaBIOS BIOS by default, expecting a bootloader to be installed
37480 in the Master Boot Record (MBR).
37482 @cindex docker-image, creating docker images
37483 When using the @code{docker} image type, a Docker image is produced.
37484 Guix builds the image from scratch, not from a pre-existing Docker base
37485 image. As a result, it contains @emph{exactly} what you define in the
37486 operating system configuration file. You can then load the image and
37487 launch a Docker container using commands like the following:
37490 image_id="$(docker load < guix-system-docker-image.tar.gz)"
37491 container_id="$(docker create $image_id)"
37492 docker start $container_id
37495 This command starts a new Docker container from the specified image. It
37496 will boot the Guix system in the usual manner, which means it will
37497 start any services you have defined in the operating system
37498 configuration. You can get an interactive shell running in the container
37499 using @command{docker exec}:
37502 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
37505 Depending on what you run in the Docker container, it
37506 may be necessary to give the container additional permissions. For
37507 example, if you intend to build software using Guix inside of the Docker
37508 container, you may need to pass the @option{--privileged} option to
37509 @code{docker create}.
37511 Last, the @option{--network} option applies to @command{guix system
37512 docker-image}: it produces an image where network is supposedly shared
37513 with the host, and thus without services like nscd or NetworkManager.
37516 Return a script to run the operating system declared in @var{file}
37517 within a container. Containers are a set of lightweight isolation
37518 mechanisms provided by the kernel Linux-libre. Containers are
37519 substantially less resource-demanding than full virtual machines since
37520 the kernel, shared objects, and other resources can be shared with the
37521 host system; this also means they provide thinner isolation.
37523 Currently, the script must be run as root in order to support more than
37524 a single user and group. The container shares its store with the host
37527 As with the @code{vm} action (@pxref{guix system vm}), additional file
37528 systems to be shared between the host and container can be specified
37529 using the @option{--share} and @option{--expose} options:
37532 guix system container my-config.scm \
37533 --expose=$HOME --share=$HOME/tmp=/exchange
37536 The @option{--share} and @option{--expose} options can also be passed to
37537 the generated script to bind-mount additional directories into the
37541 This option requires Linux-libre 3.19 or newer.
37546 @var{options} can contain any of the common build options (@pxref{Common
37547 Build Options}). In addition, @var{options} can contain one of the
37551 @item --expression=@var{expr}
37552 @itemx -e @var{expr}
37553 Consider the operating-system @var{expr} evaluates to.
37554 This is an alternative to specifying a file which evaluates to an
37556 This is used to generate the Guix system installer @pxref{Building the
37557 Installation Image}).
37559 @item --system=@var{system}
37560 @itemx -s @var{system}
37561 Attempt to build for @var{system} instead of the host system type.
37562 This works as per @command{guix build} (@pxref{Invoking guix build}).
37566 Return the derivation file name of the given operating system without
37569 @cindex provenance tracking, of the operating system
37570 @item --save-provenance
37571 As discussed above, @command{guix system init} and @command{guix system
37572 reconfigure} always save provenance information @i{via} a dedicated
37573 service (@pxref{Service Reference, @code{provenance-service-type}}).
37574 However, other commands don't do that by default. If you wish to, say,
37575 create a virtual machine image that contains provenance information, you
37579 guix system image -t qcow2 --save-provenance config.scm
37582 That way, the resulting image will effectively ``embed its own source''
37583 in the form of meta-data in @file{/run/current-system}. With that
37584 information, one can rebuild the image to make sure it really contains
37585 what it pretends to contain; or they could use that to derive a variant
37588 @item --image-type=@var{type}
37589 @itemx -t @var{type}
37590 For the @code{image} action, create an image with given @var{type}.
37592 When this option is omitted, @command{guix system} uses the
37593 @code{efi-raw} image type.
37595 @cindex ISO-9660 format
37596 @cindex CD image format
37597 @cindex DVD image format
37598 @option{--image-type=iso9660} produces an ISO-9660 image, suitable
37599 for burning on CDs and DVDs.
37601 @item --image-size=@var{size}
37602 For the @code{image} action, create an image of the given @var{size}.
37603 @var{size} may be a number of bytes, or it may include a unit as a
37604 suffix (@pxref{Block size, size specifications,, coreutils, GNU
37607 When this option is omitted, @command{guix system} computes an estimate
37608 of the image size as a function of the size of the system declared in
37613 For the @code{container} action, allow containers to access the host network,
37614 that is, do not create a network namespace.
37616 @item --root=@var{file}
37617 @itemx -r @var{file}
37618 Make @var{file} a symlink to the result, and register it as a garbage
37621 @item --skip-checks
37622 Skip pre-installation safety checks.
37624 By default, @command{guix system init} and @command{guix system
37625 reconfigure} perform safety checks: they make sure the file systems that
37626 appear in the @code{operating-system} declaration actually exist
37627 (@pxref{File Systems}), and that any Linux kernel modules that may be
37628 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
37629 RAM Disk}). Passing this option skips these tests altogether.
37631 @item --allow-downgrades
37632 Instruct @command{guix system reconfigure} to allow system downgrades.
37634 By default, @command{reconfigure} prevents you from downgrading your
37635 system. It achieves that by comparing the provenance info of your
37636 system (shown by @command{guix system describe}) with that of your
37637 @command{guix} command (shown by @command{guix describe}). If the
37638 commits for @command{guix} are not descendants of those used for your
37639 system, @command{guix system reconfigure} errors out. Passing
37640 @option{--allow-downgrades} allows you to bypass these checks.
37643 Make sure you understand its security implications before using
37644 @option{--allow-downgrades}.
37648 @cindex on-error strategy
37649 @cindex error strategy
37650 @item --on-error=@var{strategy}
37651 Apply @var{strategy} when an error occurs when reading @var{file}.
37652 @var{strategy} may be one of the following:
37655 @item nothing-special
37656 Report the error concisely and exit. This is the default strategy.
37659 Likewise, but also display a backtrace.
37662 Report the error and enter Guile's debugger. From there, you can run
37663 commands such as @code{,bt} to get a backtrace, @code{,locals} to
37664 display local variable values, and more generally inspect the state of the
37665 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
37666 a list of available debugging commands.
37670 Once you have built, configured, re-configured, and re-re-configured
37671 your Guix installation, you may find it useful to list the operating
37672 system generations available on disk---and that you can choose from the
37673 bootloader boot menu:
37678 Describe the running system generation: its file name, the kernel and
37679 bootloader used, etc., as well as provenance information when available.
37681 The @code{--list-installed} flag is available, with the same
37682 syntax that is used in @command{guix package --list-installed}
37683 (@pxref{Invoking guix package}). When the flag is used,
37684 the description will include a list of packages that are currently
37685 installed in the system profile, with optional filtering based on a
37686 regular expression.
37689 The @emph{running} system generation---referred to by
37690 @file{/run/current-system}---is not necessarily the @emph{current}
37691 system generation---referred to by @file{/var/guix/profiles/system}: it
37692 differs when, for instance, you chose from the bootloader menu to boot
37693 an older generation.
37695 It can also differ from the @emph{booted} system generation---referred
37696 to by @file{/run/booted-system}---for instance because you reconfigured
37697 the system in the meantime.
37700 @item list-generations
37701 List a summary of each generation of the operating system available on
37702 disk, in a human-readable way. This is similar to the
37703 @option{--list-generations} option of @command{guix package}
37704 (@pxref{Invoking guix package}).
37706 Optionally, one can specify a pattern, with the same syntax that is used
37707 in @command{guix package --list-generations}, to restrict the list of
37708 generations displayed. For instance, the following command displays
37709 generations that are up to 10 days old:
37712 $ guix system list-generations 10d
37715 The @code{--list-installed} flag may also be specified, with the same
37716 syntax that is used in @command{guix package --list-installed}. This
37717 may be helpful if trying to determine when a package was added to the
37722 The @command{guix system} command has even more to offer! The following
37723 sub-commands allow you to visualize how your system services relate to
37726 @anchor{system-extension-graph}
37729 @item extension-graph
37730 Emit to standard output the @dfn{service
37731 extension graph} of the operating system defined in @var{file}
37732 (@pxref{Service Composition}, for more information on service
37733 extensions). By default the output is in Dot/Graphviz format, but you
37734 can choose a different format with @option{--graph-backend}, as with
37735 @command{guix graph} (@pxref{Invoking guix graph, @option{--backend}}):
37740 $ guix system extension-graph @var{file} | xdot -
37743 shows the extension relations among services.
37746 The @command{dot} program is provided by the @code{graphviz} package.
37749 @anchor{system-shepherd-graph}
37750 @item shepherd-graph
37751 Emit to standard output the @dfn{dependency
37752 graph} of shepherd services of the operating system defined in
37753 @var{file}. @xref{Shepherd Services}, for more information and for an
37756 Again, the default output format is Dot/Graphviz, but you can pass
37757 @option{--graph-backend} to select a different one.
37761 @node Invoking guix deploy
37762 @section Invoking @code{guix deploy}
37764 We've already seen @code{operating-system} declarations used to manage a
37765 machine's configuration locally. Suppose you need to configure multiple
37766 machines, though---perhaps you're managing a service on the web that's
37767 comprised of several servers. @command{guix deploy} enables you to use those
37768 same @code{operating-system} declarations to manage multiple remote hosts at
37769 once as a logical ``deployment''.
37772 The functionality described in this section is still under development
37773 and is subject to change. Get in touch with us on
37774 @email{guix-devel@@gnu.org}!
37778 guix deploy @var{file}
37781 Such an invocation will deploy the machines that the code within @var{file}
37782 evaluates to. As an example, @var{file} might contain a definition like this:
37785 ;; This is a Guix deployment of a "bare bones" setup, with
37786 ;; no X11 display server, to a machine with an SSH daemon
37787 ;; listening on localhost:2222. A configuration such as this
37788 ;; may be appropriate for virtual machine with ports
37789 ;; forwarded to the host's loopback interface.
37791 (use-service-modules networking ssh)
37792 (use-package-modules bootloaders)
37796 (host-name "gnu-deployed")
37797 (timezone "Etc/UTC")
37798 (bootloader (bootloader-configuration
37799 (bootloader grub-bootloader)
37800 (targets '("/dev/vda"))
37801 (terminal-outputs '(console))))
37802 (file-systems (cons (file-system
37804 (device "/dev/vda1")
37806 %base-file-systems))
37808 (append (list (service dhcp-client-service-type)
37809 (service openssh-service-type
37810 (openssh-configuration
37811 (permit-root-login #t)
37812 (allow-empty-passwords? #t))))
37816 (operating-system %system)
37817 (environment managed-host-environment-type)
37818 (configuration (machine-ssh-configuration
37819 (host-name "localhost")
37820 (system "x86_64-linux")
37822 (identity "./id_rsa")
37826 The file should evaluate to a list of @var{machine} objects. This example,
37827 upon being deployed, will create a new generation on the remote system
37828 realizing the @code{operating-system} declaration @code{%system}.
37829 @code{environment} and @code{configuration} specify how the machine should be
37830 provisioned---that is, how the computing resources should be created and
37831 managed. The above example does not create any resources, as a
37832 @code{'managed-host} is a machine that is already running the Guix system and
37833 available over the network. This is a particularly simple case; a more
37834 complex deployment may involve, for example, starting virtual machines through
37835 a Virtual Private Server (VPS) provider. In such a case, a different
37836 @var{environment} type would be used.
37838 Do note that you first need to generate a key pair on the coordinator machine
37839 to allow the daemon to export signed archives of files from the store
37840 (@pxref{Invoking guix archive}), though this step is automatic on Guix
37844 # guix archive --generate-key
37848 Each target machine must authorize the key of the master machine so that it
37849 accepts store items it receives from the coordinator:
37852 # guix archive --authorize < coordinator-public-key.txt
37855 @code{user}, in this example, specifies the name of the user account to log in
37856 as to perform the deployment. Its default value is @code{root}, but root
37857 login over SSH may be forbidden in some cases. To work around this,
37858 @command{guix deploy} can log in as an unprivileged user and employ
37859 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
37860 currently installed on the remote and can be invoked non-interactively as
37861 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
37862 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
37863 be accomplished with the following operating system configuration snippet:
37867 (gnu system)) ;for %sudoers-specification
37869 (define %user "username")
37874 (plain-file "sudoers"
37875 (string-append (plain-file-content %sudoers-specification)
37876 (format #f "~a ALL = NOPASSWD: ALL~%"
37881 For more information regarding the format of the @file{sudoers} file,
37882 consult @command{man sudoers}.
37884 Once you've deployed a system on a set of machines, you may find it
37885 useful to run a command on all of them. The @option{--execute} or
37886 @option{-x} option lets you do that; the example below runs
37887 @command{uname -a} on all the machines listed in the deployment file:
37890 guix deploy @var{file} -x -- uname -a
37893 One thing you may often need to do after deployment is restart specific
37894 services on all the machines, which you can do like so:
37897 guix deploy @var{file} -x -- herd restart @var{service}
37900 The @command{guix deploy -x} command returns zero if and only if the
37901 command succeeded on all the machines.
37903 @c FIXME/TODO: Separate the API doc from the CLI doc.
37905 Below are the data types you need to know about when writing a
37908 @deftp {Data Type} machine
37909 This is the data type representing a single machine in a heterogeneous Guix
37913 @item @code{operating-system}
37914 The object of the operating system configuration to deploy.
37916 @item @code{environment}
37917 An @code{environment-type} describing how the machine should be provisioned.
37919 @item @code{configuration} (default: @code{#f})
37920 An object describing the configuration for the machine's @code{environment}.
37921 If the @code{environment} has a default configuration, @code{#f} may be used.
37922 If @code{#f} is used for an environment with no default configuration,
37923 however, an error will be thrown.
37927 @deftp {Data Type} machine-ssh-configuration
37928 This is the data type representing the SSH client parameters for a machine
37929 with an @code{environment} of @code{managed-host-environment-type}.
37932 @item @code{host-name}
37933 @item @code{build-locally?} (default: @code{#t})
37934 If false, system derivations will be built on the machine being deployed to.
37935 @item @code{system}
37936 The system type describing the architecture of the machine being deployed
37937 to---e.g., @code{"x86_64-linux"}.
37938 @item @code{authorize?} (default: @code{#t})
37939 If true, the coordinator's signing key will be added to the remote's ACL
37941 @item @code{port} (default: @code{22})
37942 @item @code{user} (default: @code{"root"})
37943 @item @code{identity} (default: @code{#f})
37944 If specified, the path to the SSH private key to use to authenticate with the
37947 @item @code{host-key} (default: @code{#f})
37948 This should be the SSH host key of the machine, which looks like this:
37951 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
37954 When @code{host-key} is @code{#f}, the server is authenticated against
37955 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
37958 @item @code{allow-downgrades?} (default: @code{#f})
37959 Whether to allow potential downgrades.
37961 Like @command{guix system reconfigure}, @command{guix deploy} compares
37962 the channel commits currently deployed on the remote host (as returned
37963 by @command{guix system describe}) to those currently in use (as
37964 returned by @command{guix describe}) to determine whether commits
37965 currently in use are descendants of those deployed. When this is not
37966 the case and @code{allow-downgrades?} is false, it raises an error.
37967 This ensures you do not accidentally downgrade remote machines.
37969 @item @code{safety-checks?} (default: @code{#t})
37970 Whether to perform ``safety checks'' before deployment. This includes
37971 verifying that devices and file systems referred to in the operating
37972 system configuration actually exist on the target machine, and making
37973 sure that Linux modules required to access storage devices at boot time
37974 are listed in the @code{initrd-modules} field of the operating system.
37976 These safety checks ensure that you do not inadvertently deploy a system
37977 that would fail to boot. Be careful before turning them off!
37981 @deftp {Data Type} digital-ocean-configuration
37982 This is the data type describing the Droplet that should be created for a
37983 machine with an @code{environment} of @code{digital-ocean-environment-type}.
37986 @item @code{ssh-key}
37987 The path to the SSH private key to use to authenticate with the remote
37988 host. In the future, this field may not exist.
37990 A list of string ``tags'' that uniquely identify the machine. Must be given
37991 such that no two machines in the deployment have the same set of tags.
37992 @item @code{region}
37993 A Digital Ocean region slug, such as @code{"nyc3"}.
37995 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
37996 @item @code{enable-ipv6?}
37997 Whether or not the droplet should be created with IPv6 networking.
38001 @node Running Guix in a VM
38002 @section Running Guix in a Virtual Machine
38004 @cindex virtual machine
38005 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM
38006 image distributed at
38007 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.qcow2}.
38008 This image is a compressed image in QCOW format. You can pass it to an
38009 emulator such as @uref{https://qemu.org/, QEMU} (see below for details).
38011 This image boots the Xfce graphical environment and it contains some
38012 commonly used tools. You can install more software in the image by running
38013 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
38014 also reconfigure the system based on its initial configuration file available
38015 as @file{/run/current-system/configuration.scm} (@pxref{Using the
38016 Configuration System}).
38018 Instead of using this pre-built image, one can also build their own
38019 image using @command{guix system image} (@pxref{Invoking guix system}).
38022 If you built your own image, you must copy it out of the store
38023 (@pxref{The Store}) and give yourself permission to write to the copy
38024 before you can use it. When invoking QEMU, you must choose a system
38025 emulator that is suitable for your hardware platform. Here is a minimal
38026 QEMU invocation that will boot the result of @command{guix system
38027 image -t qcow2} on x86_64 hardware:
38030 $ qemu-system-x86_64 \
38031 -nic user,model=virtio-net-pci \
38032 -enable-kvm -m 1024 \
38033 -device virtio-blk,drive=myhd \
38034 -drive if=none,file=/tmp/qemu-image,id=myhd
38037 Here is what each of these options means:
38040 @item qemu-system-x86_64
38041 This specifies the hardware platform to emulate. This should match the
38044 @item -nic user,model=virtio-net-pci
38045 Enable the unprivileged user-mode network stack. The guest OS can
38046 access the host but not vice versa. This is the simplest way to get the
38047 guest OS online. @code{model} specifies which network device to emulate:
38048 @code{virtio-net-pci} is a special device made for virtualized operating
38049 systems and recommended for most uses. Assuming your hardware platform is
38050 x86_64, you can get a list of available NIC models by running
38051 @command{qemu-system-x86_64 -nic model=help}.
38054 If your system has hardware virtualization extensions, enabling the
38055 virtual machine support (KVM) of the Linux kernel will make things run
38058 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
38060 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
38061 which may be insufficient for some operations.
38063 @item -device virtio-blk,drive=myhd
38064 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
38065 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
38066 better performance than if it were emulating a complete disk drive. See the
38067 QEMU and KVM documentation for more info.
38069 @item -drive if=none,file=/tmp/qemu-image,id=myhd
38070 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
38071 store of the ``myhd'' drive.
38074 The default @command{run-vm.sh} script that is returned by an invocation of
38075 @command{guix system vm} does not add a @command{-nic user} flag by default.
38076 To get network access from within the vm add the @code{(dhcp-client-service)}
38077 to your system definition and start the VM using
38078 @command{$(guix system vm config.scm) -nic user}. An important caveat of using
38079 @command{-nic user} for networking is that @command{ping} will not work, because
38080 it uses the ICMP protocol. You'll have to use a different command to check for
38081 network connectivity, for example @command{guix download}.
38083 @subsection Connecting Through SSH
38087 To enable SSH inside a VM you need to add an SSH server like
38088 @code{openssh-service-type} to your VM (@pxref{Networking Services,
38089 @code{openssh-service-type}}). In addition you need to forward the SSH port,
38090 22 by default, to the host. You can do this with
38093 $(guix system vm config.scm) -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
38096 To connect to the VM you can run
38099 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022 localhost
38102 The @command{-p} tells @command{ssh} the port you want to connect to.
38103 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
38104 every time you modify your @command{config.scm} file and the
38105 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
38106 connection to an unknown host every time you connect.
38109 If you find the above @samp{hostfwd} example not to be working (e.g.,
38110 your SSH client hangs attempting to connect to the mapped port of your
38111 VM), make sure that your Guix System VM has networking support, such as
38112 by using the @code{dhcp-client-service-type} service type.
38115 @subsection Using @command{virt-viewer} with Spice
38117 As an alternative to the default @command{qemu} graphical client you can
38118 use the @command{remote-viewer} from the @command{virt-viewer} package. To
38119 connect pass the @command{-spice port=5930,disable-ticketing} flag to
38120 @command{qemu}. See previous section for further information on how to do this.
38122 Spice also allows you to do some nice stuff like share your clipboard with your
38123 VM@. To enable that you'll also have to pass the following flags to @command{qemu}:
38126 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
38127 -chardev spicevmc,name=vdagent,id=vdagent
38128 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,\
38129 name=com.redhat.spice.0
38132 You'll also need to add the @code{(spice-vdagent-service)} to your
38133 system definition (@pxref{Miscellaneous Services, Spice service}).
38135 @node Defining Services
38136 @section Defining Services
38138 The previous sections show the available services and how one can combine
38139 them in an @code{operating-system} declaration. But how do we define
38140 them in the first place? And what is a service anyway?
38143 * Service Composition:: The model for composing services.
38144 * Service Types and Services:: Types and services.
38145 * Service Reference:: API reference.
38146 * Shepherd Services:: A particular type of service.
38147 * Complex Configurations:: Defining bindings for complex configurations.
38150 @node Service Composition
38151 @subsection Service Composition
38155 Here we define a @dfn{service} as, broadly, something that extends the
38156 functionality of the operating system. Often a service is a process---a
38157 @dfn{daemon}---started when the system boots: a secure shell server, a
38158 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
38159 whose execution can be triggered by another daemon---e.g., an FTP server
38160 started by @command{inetd} or a D-Bus service activated by
38161 @command{dbus-daemon}. Occasionally, a service does not map to a
38162 daemon. For instance, the ``account'' service collects user accounts
38163 and makes sure they exist when the system runs; the ``udev'' service
38164 collects device management rules and makes them available to the eudev
38165 daemon; the @file{/etc} service populates the @file{/etc} directory
38168 @cindex service extensions
38169 Guix system services are connected by @dfn{extensions}. For instance, the
38170 secure shell service @emph{extends} the Shepherd---the
38171 initialization system, running as PID@tie{}1---by giving it the command
38172 lines to start and stop the secure shell daemon (@pxref{Networking
38173 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
38174 service by passing it its @file{.service} specification, and extends the
38175 udev service by passing it device management rules (@pxref{Desktop
38176 Services, @code{upower-service}}); the Guix daemon service extends the
38177 Shepherd by passing it the command lines to start and stop the daemon,
38178 and extends the account service by passing it a list of required build
38179 user accounts (@pxref{Base Services}).
38181 All in all, services and their ``extends'' relations form a directed
38182 acyclic graph (DAG). If we represent services as boxes and extensions
38183 as arrows, a typical system might provide something like this:
38185 @image{images/service-graph,,5in,Typical service extension graph.}
38187 @cindex system service
38188 At the bottom, we see the @dfn{system service}, which produces the
38189 directory containing everything to run and boot the system, as returned
38190 by the @command{guix system build} command. @xref{Service Reference},
38191 to learn about the other service types shown here.
38192 @xref{system-extension-graph, the @command{guix system extension-graph}
38193 command}, for information on how to generate this representation for a
38194 particular operating system definition.
38196 @cindex service types
38197 Technically, developers can define @dfn{service types} to express these
38198 relations. There can be any number of services of a given type on the
38199 system---for instance, a system running two instances of the GNU secure
38200 shell server (lsh) has two instances of @code{lsh-service-type}, with
38201 different parameters.
38203 The following section describes the programming interface for service
38204 types and services.
38206 @node Service Types and Services
38207 @subsection Service Types and Services
38209 A @dfn{service type} is a node in the DAG described above. Let us start
38210 with a simple example, the service type for the Guix build daemon
38211 (@pxref{Invoking guix-daemon}):
38214 (define guix-service-type
38218 (list (service-extension shepherd-root-service-type guix-shepherd-service)
38219 (service-extension account-service-type guix-accounts)
38220 (service-extension activation-service-type guix-activation)))
38221 (default-value (guix-configuration))))
38225 It defines three things:
38229 A name, whose sole purpose is to make inspection and debugging easier.
38232 A list of @dfn{service extensions}, where each extension designates the
38233 target service type and a procedure that, given the parameters of the
38234 service, returns a list of objects to extend the service of that type.
38236 Every service type has at least one service extension. The only
38237 exception is the @dfn{boot service type}, which is the ultimate service.
38240 Optionally, a default value for instances of this type.
38243 In this example, @code{guix-service-type} extends three services:
38246 @item shepherd-root-service-type
38247 The @code{guix-shepherd-service} procedure defines how the Shepherd
38248 service is extended. Namely, it returns a @code{<shepherd-service>}
38249 object that defines how @command{guix-daemon} is started and stopped
38250 (@pxref{Shepherd Services}).
38252 @item account-service-type
38253 This extension for this service is computed by @code{guix-accounts},
38254 which returns a list of @code{user-group} and @code{user-account}
38255 objects representing the build user accounts (@pxref{Invoking
38258 @item activation-service-type
38259 Here @code{guix-activation} is a procedure that returns a gexp, which is
38260 a code snippet to run at ``activation time''---e.g., when the service is
38264 A service of this type is instantiated like this:
38267 (service guix-service-type
38268 (guix-configuration
38270 (extra-options '("--gc-keep-derivations"))))
38273 The second argument to the @code{service} form is a value representing
38274 the parameters of this specific service instance.
38275 @xref{guix-configuration-type, @code{guix-configuration}}, for
38276 information about the @code{guix-configuration} data type. When the
38277 value is omitted, the default value specified by
38278 @code{guix-service-type} is used:
38281 (service guix-service-type)
38284 @code{guix-service-type} is quite simple because it extends other
38285 services but is not extensible itself.
38287 @c @subsubsubsection Extensible Service Types
38289 The service type for an @emph{extensible} service looks like this:
38292 (define udev-service-type
38293 (service-type (name 'udev)
38295 (list (service-extension shepherd-root-service-type
38296 udev-shepherd-service)))
38298 (compose concatenate) ;concatenate the list of rules
38299 (extend (lambda (config rules)
38301 (($ <udev-configuration> udev initial-rules)
38302 (udev-configuration
38303 (udev udev) ;the udev package to use
38304 (rules (append initial-rules rules)))))))))
38307 This is the service type for the
38308 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
38309 management daemon}. Compared to the previous example, in addition to an
38310 extension of @code{shepherd-root-service-type}, we see two new fields:
38314 This is the procedure to @dfn{compose} the list of extensions to
38315 services of this type.
38317 Services can extend the udev service by passing it lists of rules; we
38318 compose those extensions simply by concatenating them.
38321 This procedure defines how the value of the service is @dfn{extended} with
38322 the composition of the extensions.
38324 Udev extensions are composed into a list of rules, but the udev service
38325 value is itself a @code{<udev-configuration>} record. So here, we
38326 extend that record by appending the list of rules it contains to the
38327 list of contributed rules.
38330 This is a string giving an overview of the service type. The string can
38331 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
38332 @command{guix system search} command searches these strings and displays
38333 them (@pxref{Invoking guix system}).
38336 There can be only one instance of an extensible service type such as
38337 @code{udev-service-type}. If there were more, the
38338 @code{service-extension} specifications would be ambiguous.
38340 Still here? The next section provides a reference of the programming
38341 interface for services.
38343 @node Service Reference
38344 @subsection Service Reference
38346 We have seen an overview of service types (@pxref{Service Types and
38347 Services}). This section provides a reference on how to manipulate
38348 services and service types. This interface is provided by the
38349 @code{(gnu services)} module.
38351 @deffn {Scheme Procedure} service @var{type} [@var{value}]
38352 Return a new service of @var{type}, a @code{<service-type>} object (see
38353 below). @var{value} can be any object; it represents the parameters of
38354 this particular service instance.
38356 When @var{value} is omitted, the default value specified by @var{type}
38357 is used; if @var{type} does not specify a default value, an error is
38360 For instance, this:
38363 (service openssh-service-type)
38367 is equivalent to this:
38370 (service openssh-service-type
38371 (openssh-configuration))
38374 In both cases the result is an instance of @code{openssh-service-type}
38375 with the default configuration.
38378 @deffn {Scheme Procedure} service? @var{obj}
38379 Return true if @var{obj} is a service.
38382 @deffn {Scheme Procedure} service-kind @var{service}
38383 Return the type of @var{service}---i.e., a @code{<service-type>} object.
38386 @deffn {Scheme Procedure} service-value @var{service}
38387 Return the value associated with @var{service}. It represents its
38391 Here is an example of how a service is created and manipulated:
38395 (service nginx-service-type
38396 (nginx-configuration
38398 (log-directory log-directory)
38399 (run-directory run-directory)
38400 (file config-file))))
38405 (eq? (service-kind s) nginx-service-type)
38409 The @code{modify-services} form provides a handy way to change the
38410 parameters of some of the services of a list such as
38411 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
38412 evaluates to a list of services. Of course, you could always use
38413 standard list combinators such as @code{map} and @code{fold} to do that
38414 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
38415 @code{modify-services} simply provides a more concise form for this
38418 @deffn {Scheme Syntax} modify-services @var{services} @
38419 (@var{type} @var{variable} => @var{body}) @dots{}
38421 Modify the services listed in @var{services} according to the given
38422 clauses. Each clause has the form:
38425 (@var{type} @var{variable} => @var{body})
38428 where @var{type} is a service type---e.g.,
38429 @code{guix-service-type}---and @var{variable} is an identifier that is
38430 bound within the @var{body} to the service parameters---e.g., a
38431 @code{guix-configuration} instance---of the original service of that
38434 The @var{body} should evaluate to the new service parameters, which will
38435 be used to configure the new service. This new service will replace the
38436 original in the resulting list. Because a service's service parameters
38437 are created using @code{define-record-type*}, you can write a succinct
38438 @var{body} that evaluates to the new service parameters by using the
38439 @code{inherit} feature that @code{define-record-type*} provides.
38441 Clauses can also have the following form:
38444 (delete @var{type})
38447 Such a clause removes all services of the given @var{type} from
38450 @xref{Using the Configuration System}, for example usage.
38454 Next comes the programming interface for service types. This is
38455 something you want to know when writing new service definitions, but not
38456 necessarily when simply looking for ways to customize your
38457 @code{operating-system} declaration.
38459 @deftp {Data Type} service-type
38460 @cindex service type
38461 This is the representation of a @dfn{service type} (@pxref{Service Types
38466 This is a symbol, used only to simplify inspection and debugging.
38468 @item @code{extensions}
38469 A non-empty list of @code{<service-extension>} objects (see below).
38471 @item @code{compose} (default: @code{#f})
38472 If this is @code{#f}, then the service type denotes services that cannot
38473 be extended---i.e., services that do not receive ``values'' from other
38476 Otherwise, it must be a one-argument procedure. The procedure is called
38477 by @code{fold-services} and is passed a list of values collected from
38478 extensions. It may return any single value.
38480 @item @code{extend} (default: @code{#f})
38481 If this is @code{#f}, services of this type cannot be extended.
38483 Otherwise, it must be a two-argument procedure: @code{fold-services}
38484 calls it, passing it the initial value of the service as the first
38485 argument and the result of applying @code{compose} to the extension
38486 values as the second argument. It must return a value that is a valid
38487 parameter value for the service instance.
38489 @item @code{description}
38490 This is a string, possibly using Texinfo markup, describing in a couple
38491 of sentences what the service is about. This string allows users to
38492 find about the service through @command{guix system search}
38493 (@pxref{Invoking guix system}).
38495 @item @code{default-value} (default: @code{&no-default-value})
38496 The default value associated for instances of this service type. This
38497 allows users to use the @code{service} form without its second argument:
38500 (service @var{type})
38503 The returned service in this case has the default value specified by
38507 @xref{Service Types and Services}, for examples.
38510 @deffn {Scheme Procedure} service-extension @var{target-type} @
38512 Return a new extension for services of type @var{target-type}.
38513 @var{compute} must be a one-argument procedure: @code{fold-services}
38514 calls it, passing it the value associated with the service that provides
38515 the extension; it must return a valid value for the target service.
38518 @deffn {Scheme Procedure} service-extension? @var{obj}
38519 Return true if @var{obj} is a service extension.
38522 Occasionally, you might want to simply extend an existing service. This
38523 involves creating a new service type and specifying the extension of
38524 interest, which can be verbose; the @code{simple-service} procedure
38525 provides a shorthand for this.
38527 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
38528 Return a service that extends @var{target} with @var{value}. This works
38529 by creating a singleton service type @var{name}, of which the returned
38530 service is an instance.
38532 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
38536 (simple-service 'my-mcron-job mcron-service-type
38537 #~(job '(next-hour (3)) "guix gc -F 2G"))
38541 At the core of the service abstraction lies the @code{fold-services}
38542 procedure, which is responsible for ``compiling'' a list of services
38543 down to a single directory that contains everything needed to boot and
38544 run the system---the directory shown by the @command{guix system build}
38545 command (@pxref{Invoking guix system}). In essence, it propagates
38546 service extensions down the service graph, updating each node parameters
38547 on the way, until it reaches the root node.
38549 @deffn {Scheme Procedure} fold-services @var{services} @
38550 [#:target-type @var{system-service-type}]
38551 Fold @var{services} by propagating their extensions down to the root of
38552 type @var{target-type}; return the root service adjusted accordingly.
38555 Lastly, the @code{(gnu services)} module also defines several essential
38556 service types, some of which are listed below.
38558 @defvr {Scheme Variable} system-service-type
38559 This is the root of the service graph. It produces the system directory
38560 as returned by the @command{guix system build} command.
38563 @defvr {Scheme Variable} boot-service-type
38564 The type of the ``boot service'', which produces the @dfn{boot script}.
38565 The boot script is what the initial RAM disk runs when booting.
38568 @defvr {Scheme Variable} etc-service-type
38569 The type of the @file{/etc} service. This service is used to create
38570 files under @file{/etc} and can be extended by
38571 passing it name/file tuples such as:
38574 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
38577 In this example, the effect would be to add an @file{/etc/issue} file
38578 pointing to the given file.
38581 @defvr {Scheme Variable} setuid-program-service-type
38582 Type for the ``setuid-program service''. This service collects lists of
38583 executable file names, passed as gexps, and adds them to the set of
38584 setuid and setgid programs on the system (@pxref{Setuid Programs}).
38587 @defvr {Scheme Variable} profile-service-type
38588 Type of the service that populates the @dfn{system profile}---i.e., the
38589 programs under @file{/run/current-system/profile}. Other services can
38590 extend it by passing it lists of packages to add to the system profile.
38593 @cindex provenance tracking, of the operating system
38594 @anchor{provenance-service-type}
38595 @defvr {Scheme Variable} provenance-service-type
38596 This is the type of the service that records @dfn{provenance meta-data}
38597 in the system itself. It creates several files under
38598 @file{/run/current-system}:
38602 This is a ``channel file'' that can be passed to @command{guix pull -C}
38603 or @command{guix time-machine -C}, and which describes the channels used
38604 to build the system, if that information was available
38605 (@pxref{Channels}).
38607 @item configuration.scm
38608 This is the file that was passed as the value for this
38609 @code{provenance-service-type} service. By default, @command{guix
38610 system reconfigure} automatically passes the OS configuration file it
38611 received on the command line.
38614 This contains the same information as the two other files but in a
38615 format that is more readily processable.
38618 In general, these two pieces of information (channels and configuration
38619 file) are enough to reproduce the operating system ``from source''.
38622 This information is necessary to rebuild your operating system, but it
38623 is not always sufficient. In particular, @file{configuration.scm}
38624 itself is insufficient if it is not self-contained---if it refers to
38625 external Guile modules or to extra files. If you want
38626 @file{configuration.scm} to be self-contained, we recommend that modules
38627 or files it refers to be part of a channel.
38629 Besides, provenance meta-data is ``silent'' in the sense that it does
38630 not change the bits contained in your system, @emph{except for the
38631 meta-data bits themselves}. Two different OS configurations or sets of
38632 channels can lead to the same system, bit-for-bit; when
38633 @code{provenance-service-type} is used, these two systems will have
38634 different meta-data and thus different store file names, which makes
38635 comparison less trivial.
38638 This service is automatically added to your operating system
38639 configuration when you use @command{guix system reconfigure},
38640 @command{guix system init}, or @command{guix deploy}.
38643 @defvr {Scheme Variable} linux-loadable-module-service-type
38644 Type of the service that collects lists of packages containing
38645 kernel-loadable modules, and adds them to the set of kernel-loadable
38648 This service type is intended to be extended by other service types,
38652 (simple-service 'installing-module
38653 linux-loadable-module-service-type
38654 (list module-to-install-1
38655 module-to-install-2))
38658 This does not actually load modules at bootup, only adds it to the
38659 kernel profile so that it @emph{can} be loaded by other means.
38662 @node Shepherd Services
38663 @subsection Shepherd Services
38665 @cindex shepherd services
38667 @cindex init system
38668 The @code{(gnu services shepherd)} module provides a way to define
38669 services managed by the GNU@tie{}Shepherd, which is the
38670 initialization system---the first process that is started when the
38671 system boots, also known as PID@tie{}1
38672 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
38674 Services in the Shepherd can depend on each other. For instance, the
38675 SSH daemon may need to be started after the syslog daemon has been
38676 started, which in turn can only happen once all the file systems have
38677 been mounted. The simple operating system defined earlier (@pxref{Using
38678 the Configuration System}) results in a service graph like this:
38680 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
38682 You can actually generate such a graph for any operating system
38683 definition using the @command{guix system shepherd-graph} command
38684 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
38686 The @code{%shepherd-root-service} is a service object representing
38687 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
38688 by passing it lists of @code{<shepherd-service>} objects.
38690 @deftp {Data Type} shepherd-service
38691 The data type representing a service managed by the Shepherd.
38694 @item @code{provision}
38695 This is a list of symbols denoting what the service provides.
38697 These are the names that may be passed to @command{herd start},
38698 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
38699 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
38700 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
38702 @item @code{requirement} (default: @code{'()})
38703 List of symbols denoting the Shepherd services this one depends on.
38705 @cindex one-shot services, for the Shepherd
38706 @item @code{one-shot?} (default: @code{#f})
38707 Whether this service is @dfn{one-shot}. One-shot services stop immediately
38708 after their @code{start} action has completed. @xref{Slots of services,,,
38709 shepherd, The GNU Shepherd Manual}, for more info.
38711 @item @code{respawn?} (default: @code{#t})
38712 Whether to restart the service when it stops, for instance when the
38713 underlying process dies.
38716 @itemx @code{stop} (default: @code{#~(const #f)})
38717 The @code{start} and @code{stop} fields refer to the Shepherd's
38718 facilities to start and stop processes (@pxref{Service De- and
38719 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
38720 G-expressions that get expanded in the Shepherd configuration file
38721 (@pxref{G-Expressions}).
38723 @item @code{actions} (default: @code{'()})
38724 @cindex actions, of Shepherd services
38725 This is a list of @code{shepherd-action} objects (see below) defining
38726 @dfn{actions} supported by the service, in addition to the standard
38727 @code{start} and @code{stop} actions. Actions listed here become available as
38728 @command{herd} sub-commands:
38731 herd @var{action} @var{service} [@var{arguments}@dots{}]
38734 @item @code{auto-start?} (default: @code{#t})
38735 Whether this service should be started automatically by the Shepherd. If it
38736 is @code{#f} the service has to be started manually with @code{herd start}.
38738 @item @code{documentation}
38739 A documentation string, as shown when running:
38742 herd doc @var{service-name}
38745 where @var{service-name} is one of the symbols in @code{provision}
38746 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
38748 @item @code{modules} (default: @code{%default-modules})
38749 This is the list of modules that must be in scope when @code{start} and
38750 @code{stop} are evaluated.
38755 The example below defines a Shepherd service that spawns
38756 @command{syslogd}, the system logger from the GNU Networking Utilities
38757 (@pxref{syslogd invocation, @command{syslogd},, inetutils, GNU
38761 (let ((config (plain-file "syslogd.conf" "@dots{}")))
38763 (documentation "Run the syslog daemon (syslogd).")
38764 (provision '(syslogd))
38765 (requirement '(user-processes))
38766 (start #~(make-forkexec-constructor
38767 (list #$(file-append inetutils "/libexec/syslogd")
38768 "--rcfile" #$config)
38769 #:pid-file "/var/run/syslog.pid"))
38770 (stop #~(make-kill-destructor))))
38773 Key elements in this example are the @code{start} and @code{stop}
38774 fields: they are @dfn{staged} code snippets that use the
38775 @code{make-forkexec-constructor} procedure provided by the Shepherd and
38776 its dual, @code{make-kill-destructor} (@pxref{Service De- and
38777 Constructors,,, shepherd, The GNU Shepherd Manual}). The @code{start}
38778 field will have @command{shepherd} spawn @command{syslogd} with the
38779 given option; note that we pass @code{config} after @option{--rcfile},
38780 which is a configuration file declared above (contents of this file are
38781 omitted). Likewise, the @code{stop} field tells how this service is to
38782 be stopped; in this case, it is stopped by making the @code{kill} system
38783 call on its PID@. Code staging is achieved using G-expressions:
38784 @code{#~} stages code, while @code{#$} ``escapes'' back to host code
38785 (@pxref{G-Expressions}).
38787 @deftp {Data Type} shepherd-action
38788 This is the data type that defines additional actions implemented by a
38789 Shepherd service (see above).
38793 Symbol naming the action.
38795 @item documentation
38796 This is a documentation string for the action. It can be viewed by running:
38799 herd doc @var{service} action @var{action}
38803 This should be a gexp that evaluates to a procedure of at least one argument,
38804 which is the ``running value'' of the service (@pxref{Slots of services,,,
38805 shepherd, The GNU Shepherd Manual}).
38808 The following example defines an action called @code{say-hello} that kindly
38814 (documentation "Say hi!")
38815 (procedure #~(lambda (running . args)
38816 (format #t "Hello, friend! arguments: ~s\n"
38821 Assuming this action is added to the @code{example} service, then you can do:
38824 # herd say-hello example
38825 Hello, friend! arguments: ()
38826 # herd say-hello example a b c
38827 Hello, friend! arguments: ("a" "b" "c")
38830 This, as you can see, is a fairly sophisticated way to say hello.
38831 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
38835 @defvr {Scheme Variable} shepherd-root-service-type
38836 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
38838 This is the service type that extensions target when they want to create
38839 shepherd services (@pxref{Service Types and Services}, for an example).
38840 Each extension must pass a list of @code{<shepherd-service>}. Its
38841 value must be a @code{shepherd-configuration}, as described below.
38844 @deftp {Data Type} shepherd-configuration
38845 This data type represents the Shepherd's configuration.
38848 @item shepherd (default: @code{shepherd})
38849 The Shepherd package to use.
38851 @item services (default: @code{'()})
38852 A list of @code{<shepherd-service>} to start.
38853 You should probably use the service extension
38854 mechanism instead (@pxref{Shepherd Services}).
38858 The following example specifies the Shepherd package for the operating
38864 (services (append (list openssh-service-type))
38868 ;; Use own Shepherd package.
38869 (essential-services
38870 (modify-services (operating-system-default-essential-services
38871 this-operating-system)
38872 (shepherd-root-service-type config => (shepherd-configuration
38874 (shepherd my-shepherd))))))
38877 @defvr {Scheme Variable} %shepherd-root-service
38878 This service represents PID@tie{}1.
38881 @node Complex Configurations
38882 @subsection Complex Configurations
38883 @cindex complex configurations
38884 Some programs might have rather complex configuration files or formats,
38885 and to make it easier to create Scheme bindings for these configuration
38886 files, you can use the utilities defined in the @code{(gnu services
38887 configuration)} module.
38889 The main utility is the @code{define-configuration} macro, which you
38890 will use to define a Scheme record type (@pxref{Record Overview,,,
38891 guile, GNU Guile Reference Manual}). The Scheme record will be
38892 serialized to a configuration file by using @dfn{serializers}, which are
38893 procedures that take some kind of Scheme value and returns a
38894 G-expression (@pxref{G-Expressions}), which should, once serialized to
38895 the disk, return a string. More details are listed below.
38897 @deffn {Scheme Syntax} define-configuration @var{name} @var{clause1} @
38899 Create a record type named @code{@var{name}} that contains the
38900 fields found in the clauses.
38902 A clause can have one of the following forms:
38906 (@var{type} @var{default-value})
38907 @var{documentation})
38910 (@var{type} @var{default-value})
38911 @var{documentation}
38916 @var{documentation})
38920 @var{documentation}
38924 @var{field-name} is an identifier that denotes the name of the field in
38925 the generated record.
38927 @var{type} is the type of the value corresponding to @var{field-name};
38928 since Guile is untyped, a predicate
38929 procedure---@code{@var{type}?}---will be called on the value
38930 corresponding to the field to ensure that the value is of the correct
38931 type. This means that if say, @var{type} is @code{package}, then a
38932 procedure named @code{package?} will be applied on the value to make
38933 sure that it is indeed a @code{<package>} object.
38935 @var{default-value} is the default value corresponding to the field; if
38936 none is specified, the user is forced to provide a value when creating
38937 an object of the record type.
38939 @c XXX: Should these be full sentences or are they allow to be very
38940 @c short like package synopses?
38941 @var{documentation} is a string formatted with Texinfo syntax which
38942 should provide a description of what setting this field does.
38944 @var{serializer} is the name of a procedure which takes two arguments,
38945 the first is the name of the field, and the second is the value
38946 corresponding to the field. The procedure should return a string or
38947 G-expression (@pxref{G-Expressions}) that represents the content that
38948 will be serialized to the configuration file. If none is specified, a
38949 procedure of the name @code{serialize-@var{type}} will be used.
38951 A simple serializer procedure could look like this:
38954 (define (serialize-boolean field-name value)
38955 (let ((value (if value "true" "false")))
38956 #~(string-append #$field-name #$value)))
38959 In some cases multiple different configuration records might be defined
38960 in the same file, but their serializers for the same type might have to
38961 be different, because they have different configuration formats. For
38962 example, the @code{serialize-boolean} procedure for the Getmail service
38963 would have to be different from the one for the Transmission service. To
38964 make it easier to deal with this situation, one can specify a serializer
38965 prefix by using the @code{prefix} literal in the
38966 @code{define-configuration} form. This means that one doesn't have to
38967 manually specify a custom @var{serializer} for every field.
38970 (define (foo-serialize-string field-name value)
38973 (define (bar-serialize-string field-name value)
38976 (define-configuration foo-configuration
38979 "The name of label.")
38982 (define-configuration bar-configuration
38985 "The IPv4 address for this device.")
38989 However, in some cases you might not want to serialize any of the values
38990 of the record, to do this, you can use the @code{no-serialization}
38991 literal. There is also the @code{define-configuration/no-serialization}
38992 macro which is a shorthand of this.
38995 ;; Nothing will be serialized to disk.
38996 (define-configuration foo-configuration
38999 "Some documentation.")
39000 (no-serialization))
39002 ;; The same thing as above.
39003 (define-configuration/no-serialization bar-configuration
39006 "Some documentation."))
39010 @deffn {Scheme Syntax} define-maybe @var{type}
39011 Sometimes a field should not be serialized if the user doesn’t specify a
39012 value. To achieve this, you can use the @code{define-maybe} macro to
39013 define a ``maybe type''; if the value of a maybe type is left unset, or
39014 is set to the @code{%unset-value} value, then it will not be serialized.
39016 When defining a ``maybe type'', the corresponding serializer for the
39017 regular type will be used by default. For example, a field of type
39018 @code{maybe-string} will be serialized using the @code{serialize-string}
39019 procedure by default, you can of course change this by specifying a
39020 custom serializer procedure. Likewise, the type of the value would have
39021 to be a string, or left unspecified.
39024 (define-maybe string)
39026 (define (serialize-string field-name value)
39029 (define-configuration baz-configuration
39031 ;; If set to a string, the `serialize-string' procedure will be used
39032 ;; to serialize the string. Otherwise this field is not serialized.
39034 "The name of this module."))
39037 Like with @code{define-configuration}, one can set a prefix for the
39038 serializer name by using the @code{prefix} literal.
39041 (define-maybe integer
39044 (define (baz-serialize-integer field-name value)
39048 There is also the @code{no-serialization} literal, which when set means
39049 that no serializer will be defined for the ``maybe type'', regardless of
39050 whether its value is set or not.
39051 @code{define-maybe/no-serialization} is a shorthand for specifying the
39052 @code{no-serialization} literal.
39055 (define-maybe/no-serialization symbol)
39057 (define-configuration/no-serialization test-configuration
39064 @deffn (Scheme Procedure) maybe-value-set? @var{value}
39065 Predicate to check whether a user explicitly specified the value of a
39069 @deffn {Scheme Procedure} serialize-configuration @var{configuration} @
39071 Return a G-expression that contains the values corresponding to the
39072 @var{fields} of @var{configuration}, a record that has been generated by
39073 @code{define-configuration}. The G-expression can then be serialized to
39074 disk by using something like @code{mixed-text-file}.
39077 @deffn {Scheme Procedure} empty-serializer @var{field-name} @var{value}
39078 A serializer that just returns an empty string. The
39079 @code{serialize-package} procedure is an alias for this.
39082 Once you have defined a configuration record, you will most likely also
39083 want to document it so that other people know to use it. To help with
39084 that, there are two procedures, both of which are documented below.
39086 @deffn {Scheme Procedure} generate-documentation @var{documentation} @
39087 @var{documentation-name}
39088 Generate a Texinfo fragment from the docstrings in @var{documentation},
39089 a list of @code{(@var{label} @var{fields} @var{sub-documentation} ...)}.
39090 @var{label} should be a symbol and should be the name of the
39091 configuration record. @var{fields} should be a list of all the fields
39092 available for the configuration record.
39094 @var{sub-documentation} is a @code{(@var{field-name}
39095 @var{configuration-name})} tuple. @var{field-name} is the name of the
39096 field which takes another configuration record as its value, and
39097 @var{configuration-name} is the name of that configuration record.
39099 @var{sub-documentation} is only needed if there are nested configuration
39100 records. For example, the @code{getmail-configuration} record
39101 (@pxref{Mail Services}) accepts a @code{getmail-configuration-file}
39102 record in one of its @code{rcfile} field, therefore documentation for
39103 @code{getmail-configuration-file} is nested in
39104 @code{getmail-configuration}.
39107 (generate-documentation
39108 `((getmail-configuration ,getmail-configuration-fields
39109 (rcfile getmail-configuration-file))
39111 'getmail-configuration)
39114 @var{documentation-name} should be a symbol and should be the name of
39115 the configuration record.
39119 @deffn {Scheme Procedure} configuration->documentation
39120 @var{configuration-symbol}
39121 Take @var{configuration-symbol}, the symbol corresponding to the name
39122 used when defining a configuration record with
39123 @code{define-configuration}, and print the Texinfo documentation of its
39124 fields. This is useful if there aren’t any nested configuration records
39125 since it only prints the documentation for the top-level fields.
39128 As of right now, there is no automated way to generate documentation for
39129 configuration records and put them in the manual. Instead, every
39130 time you make a change to the docstrings of a configuration record, you
39131 have to manually call @code{generate-documentation} or
39132 @code{configuration->documentation}, and paste the output into the
39133 @file{doc/guix.texi} file.
39135 @c TODO: Actually test this
39136 Below is an example of a record type created using
39137 @code{define-configuration} and friends.
39140 (use-modules (gnu services)
39142 (gnu services configuration)
39146 ;; Turn field names, which are Scheme symbols into strings
39147 (define (uglify-field-name field-name)
39148 (let ((str (symbol->string field-name)))
39149 ;; field? -> is-field
39150 (if (string-suffix? "?" str)
39151 (string-append "is-" (string-drop-right str 1))
39154 (define (serialize-string field-name value)
39155 #~(string-append #$(uglify-field-name field-name) " = " #$value "\n"))
39157 (define (serialize-integer field-name value)
39158 (serialize-string field-name (number->string value)))
39160 (define (serialize-boolean field-name value)
39161 (serialize-string field-name (if value "true" "false")))
39163 (define (serialize-contact-name field-name value)
39164 #~(string-append "\n[" #$value "]\n"))
39166 (define (list-of-contact-configurations? lst)
39167 (every contact-configuration? lst))
39169 (define (serialize-list-of-contact-configurations field-name value)
39170 #~(string-append #$@@(map (cut serialize-configuration <>
39171 contact-configuration-fields)
39174 (define (serialize-contacts-list-configuration configuration)
39177 #~(string-append "[Owner]\n"
39178 #$(serialize-configuration
39179 configuration contacts-list-configuration-fields))))
39181 (define-maybe integer)
39182 (define-maybe string)
39184 (define-configuration contact-configuration
39187 "The name of the contact."
39188 serialize-contact-name)
39191 "The person's phone number.")
39194 "The person's email address.")
39197 "Whether the person is married."))
39199 (define-configuration contacts-list-configuration
39202 "The name of the owner of this contact list.")
39205 "The owner's email address.")
39207 (list-of-contact-configurations '())
39208 "A list of @@code@{contact-configuation@} records which contain
39209 information about all your contacts."))
39212 A contacts list configuration could then be created like this:
39215 (define my-contacts
39216 (contacts-list-configuration
39218 (email "alice@@example.org")
39220 (list (contact-configuration
39222 (phone-number 1234)
39223 (email "bob@@gnu.org")
39225 (contact-configuration
39227 (phone-number 0000)
39231 After serializing the configuration to disk, the resulting file would
39237 email = alice@@example.org
39240 phone-number = 1234
39241 email = bob@@gnu.org
39250 @node Home Configuration
39251 @chapter Home Configuration
39252 @cindex home configuration
39253 Guix supports declarative configuration of @dfn{home environments} by
39254 utilizing the configuration mechanism described in the previous chapter
39255 (@pxref{Defining Services}), but for user's dotfiles and packages. It
39256 works both on Guix System and foreign distros and allows users to
39257 declare all the packages and services that should be installed and
39258 configured for the user. Once a user has written a file containing
39259 @code{home-environment} record, such a configuration can be
39260 @dfn{instantiated} by an unprivileged user with the @command{guix home}
39261 command (@pxref{Invoking guix home}).
39262 @c Maybe later, it will be possible to make home configuration a part of
39263 @c system configuration to make everything managed by guix system.
39266 The functionality described in this section is still under development
39267 and is subject to change. Get in touch with us on
39268 @email{guix-devel@@gnu.org}!
39271 The user's home environment usually consists of three basic parts:
39272 software, configuration, and state. Software in mainstream distros are
39273 usually installed system-wide, but with GNU Guix most software packages
39274 can be installed on a per-user basis without needing root privileges,
39275 and are thus considered part of the user’s @dfn{home environment}.
39276 Packages on their own are not very useful in many cases, because often they
39277 require some additional configuration, usually config files that reside
39278 in @env{XDG_CONFIG_HOME} (@file{~/.config} by default) or other
39279 directories. Everything else can be considered state, like media files,
39280 application databases, and logs.
39282 Using Guix for managing home environments provides a number of
39287 @item All software can be configured in one language (Guile Scheme),
39288 this gives users the ability to share values between configurations of
39289 different programs.
39291 @item A well-defined home environment is self-contained and can be
39292 created in a declarative and reproducible way---there is no need to grab
39293 external binaries or manually edit some configuration file.
39295 @item After every @command{guix home reconfigure} invocation, a new home
39296 environment generation will be created. This means that users can
39297 rollback to a previous home environment generation so they don’t have to
39298 worry about breaking their configuration.
39300 @item It is possible to manage stateful data with Guix Home, this
39301 includes the ability to automatically clone Git repositories on the
39302 initial setup of the machine, and periodically running commands like
39303 @command{rsync} to sync data with another host. This functionality is
39304 still in an experimental stage, though.
39309 * Declaring the Home Environment:: Customizing your Home.
39310 * Configuring the Shell:: Enabling home environment.
39311 * Home Services:: Specifying home services.
39312 * Invoking guix home:: Instantiating a home configuration.
39315 @node Declaring the Home Environment
39316 @section Declaring the Home Environment
39317 The home environment is configured by providing a
39318 @code{home-environment} declaration in a file that can be passed to the
39319 @command{guix home} command (@pxref{Invoking guix home}). The easiest
39320 way to get started is by generating an initial configuration with
39321 @command{guix home import}:
39324 guix home import ~/src/guix-config
39327 The @command{guix home import} command reads some of the ``dot files''
39328 such as @file{~/.bashrc} found in your home directory and copies them to
39329 the given directory, @file{~/src/guix-config} in this case; it also
39330 reads the contents of your profile, @file{~/.guix-profile}, and, based
39331 on that, it populates @file{~/src/guix-config/home-configuration.scm}
39332 with a Home configuration that resembles your current configuration.
39334 A simple setup can include Bash and a custom text configuration, like in
39335 the example below. Don't be afraid to declare home environment parts,
39336 which overlaps with your current dot files: before installing any
39337 configuration files, Guix Home will back up existing config files to a
39338 separate place in the home directory.
39341 It is highly recommended that you manage your shell or shells with Guix
39342 Home, because it will make sure that all the necessary scripts are
39343 sourced by the shell configuration file. Otherwise you will need to do
39344 it manually. (@pxref{Configuring the Shell}).
39347 @findex home-environment
39349 @include he-config-bare-bones.scm
39352 The @code{packages} field should be self-explanatory, it will install
39353 the list of packages into the user's profile. The most important field
39354 is @code{services}, it contains a list of @dfn{home services}, which are
39355 the basic building blocks of a home environment.
39357 There is no daemon (at least not necessarily) related to a home service,
39358 a home service is just an element that is used to declare part of home
39359 environment and extend other parts of it. The extension mechanism
39360 discussed in the previous chapter (@pxref{Defining Services}) should not
39361 be confused with Shepherd services (@pxref{Shepherd Services}). Using this extension
39362 mechanism and some Scheme code that glues things together gives the user
39363 the freedom to declare their own, very custom, home environments.
39365 @cindex container, for @command{guix home}
39366 Once the configuration looks good, you can first test it in a throw-away
39370 guix home container config.scm
39373 The command above spawns a shell where your home environment is running.
39374 The shell runs in a container, meaning it's isolated from the rest of
39375 the system, so it's a good way to try out your configuration---you can
39376 see if configuration bits are missing or misbehaving, if daemons get
39377 started, and so on. Once you exit that shell, you're back to the prompt
39378 of your original shell ``in the real world''.
39380 Once you have a configuration file that suits your needs, you can
39381 reconfigure your home by running:
39384 guix home reconfigure config.scm
39387 This ``builds'' your home environment and creates @file{~/.guix-home}
39388 pointing to it. Voilà!
39391 Make sure the operating system has elogind, systemd, or a similar
39392 mechanism to create the XDG run-time directory and has the
39393 @env{XDG_RUNTIME_DIR} variable set. Failing that, the
39394 @file{on-first-login} script will not execute anything, and processes
39395 like user Shepherd and its descendants will not start.
39398 @node Configuring the Shell
39399 @section Configuring the Shell
39400 This section is safe to skip if your shell or shells are managed by
39401 Guix Home. Otherwise, read it carefully.
39403 There are a few scripts that must be evaluated by a login shell to
39404 activate the home environment. The shell startup files only read by
39405 login shells often have @code{profile} suffix. For more information
39406 about login shells see @ref{Invoking Bash,,, bash, The GNU Bash
39407 Reference Manual} and see @ref{Bash Startup Files,,, bash, The GNU Bash
39410 The first script that needs to be sourced is @file{setup-environment},
39411 which sets all the necessary environment variables (including variables
39412 declared by the user) and the second one is @file{on-first-login}, which
39413 starts Shepherd for the current user and performs actions declared by
39414 other home services that extends
39415 @code{home-run-on-first-login-service-type}.
39417 Guix Home will always create @file{~/.profile}, which contains the
39421 HOME_ENVIRONMENT=$HOME/.guix-home
39422 . $HOME_ENVIRONMENT/setup-environment
39423 $HOME_ENVIRONMENT/on-first-login
39426 This makes POSIX compliant login shells activate the home environment.
39427 However, in most cases this file won't be read by most modern shells,
39428 because they are run in non POSIX mode by default and have their own
39429 @file{*profile} startup files. For example Bash will prefer
39430 @file{~/.bash_profile} in case it exists and only if it doesn't will it
39431 fallback to @file{~/.profile}. Zsh (if no additional options are
39432 specified) will ignore @file{~/.profile}, even if @file{~/.zprofile}
39435 To make your shell respect @file{~/.profile}, add @code{. ~/.profile} or
39436 @code{source ~/.profile} to the startup file for the login shell. In
39437 case of Bash, it is @file{~/.bash_profile}, and in case of Zsh, it is
39438 @file{~/.zprofile}.
39441 This step is only required if your shell is @emph{not} managed by Guix Home.
39442 Otherwise, everything will be done automatically.
39445 @node Home Services
39446 @section Home Services
39447 @cindex home services
39449 A @dfn{home service} is not necessarily something that has a daemon and
39450 is managed by Shepherd (@pxref{Jump Start,,, shepherd, The GNU Shepherd
39451 Manual}), in most cases it doesn't. It's a simple building block of the
39452 home environment, often declaring a set of packages to be installed in
39453 the home environment profile, a set of config files to be symlinked into
39454 @env{XDG_CONFIG_HOME} (@file{~/.config} by default), and environment
39455 variables to be set by a login shell.
39457 There is a service extension mechanism (@pxref{Service Composition})
39458 which allows home services to extend other home services and utilize
39459 capabilities they provide; for example: declare mcron jobs
39460 (@pxref{Top,,, mcron, GNU@tie{}Mcron}) by extending @ref{Mcron Home
39461 Service}; declare daemons by extending @ref{Shepherd Home Service}; add
39462 commands, which will be invoked on by the Bash by extending
39463 @ref{Shells Home Services, @code{home-bash-service-type}}.
39465 A good way to discover available home services is using the
39466 @command{guix home search} command (@pxref{Invoking guix home}). After
39467 the required home services are found, include its module with the
39468 @code{use-modules} form (@pxref{use-modules,, Using Guile Modules,
39469 guile, The GNU Guile Reference Manual}), or the @code{#:use-modules}
39470 directive (@pxref{define-module,, Creating Guile Modules, guile, The GNU
39471 Guile Reference Manual}) and declare a home service using the
39472 @code{service} function, or extend a service type by declaring a new
39473 service with the @code{simple-service} procedure from @code{(gnu
39477 * Essential Home Services:: Environment variables, packages, on-* scripts.
39478 * Shells: Shells Home Services. POSIX shells, Bash, Zsh.
39479 * Mcron: Mcron Home Service. Scheduled User's Job Execution.
39480 * Shepherd: Shepherd Home Service. Managing User's Daemons.
39481 * SSH: Secure Shell. Setting up the secure shell client.
39482 * Desktop: Desktop Home Services. Services for graphical environments.
39483 * Guix: Guix Home Services. Services for Guix.
39485 @c In addition to that Home Services can provide
39487 @node Essential Home Services
39488 @subsection Essential Home Services
39489 There are a few essential home services defined in
39490 @code{(gnu services)}, they are mostly for internal use and are required
39491 to build a home environment, but some of them will be useful for the end
39494 @cindex environment variables
39496 @defvr {Scheme Variable} home-environment-variables-service-type
39497 The service of this type will be instantiated by every home environment
39498 automatically by default, there is no need to define it, but someone may
39499 want to extend it with a list of pairs to set some environment
39503 (list ("ENV_VAR1" . "value1")
39504 ("ENV_VAR2" . "value2"))
39507 The easiest way to extend a service type, without defining a new service
39508 type is to use the @code{simple-service} helper from @code{(gnu
39512 (simple-service 'some-useful-env-vars-service
39513 home-environment-variables-service-type
39514 `(("LESSHISTFILE" . "$XDG_CACHE_HOME/.lesshst")
39515 ("SHELL" . ,(file-append zsh "/bin/zsh"))
39516 ("USELESS_VAR" . #f)
39517 ("_JAVA_AWT_WM_NONREPARENTING" . #t)))
39520 If you include such a service in you home environment definition, it
39521 will add the following content to the @file{setup-environment} script
39522 (which is expected to be sourced by the login shell):
39525 export LESSHISTFILE=$XDG_CACHE_HOME/.lesshst
39526 export SHELL=/gnu/store/2hsg15n644f0glrcbkb1kqknmmqdar03-zsh-5.8/bin/zsh
39527 export _JAVA_AWT_WM_NONREPARENTING
39531 Make sure that module @code{(gnu packages shells)} is imported with
39532 @code{use-modules} or any other way, this namespace contains the
39533 definition of the @code{zsh} package, which is used in the example
39537 The association list (@pxref{Association Lists, alists, Association
39538 Lists, guile, The GNU Guile Reference manual}) is a data structure
39539 containing key-value pairs, for
39540 @code{home-environment-variables-service-type} the key is always a
39541 string, the value can be a string, string-valued gexp
39542 (@pxref{G-Expressions}), file-like object (@pxref{G-Expressions,
39543 file-like object}) or boolean. For gexps, the variable will be set to
39544 the value of the gexp; for file-like objects, it will be set to the path
39545 of the file in the store (@pxref{The Store}); for @code{#t}, it will
39546 export the variable without any value; and for @code{#f}, it will omit
39551 @defvr {Scheme Variable} home-profile-service-type
39552 The service of this type will be instantiated by every home environment
39553 automatically, there is no need to define it, but you may want to extend
39554 it with a list of packages if you want to install additional packages
39555 into your profile. Other services, which need to make some programs
39556 available to the user will also extend this service type.
39558 The extension value is just a list of packages:
39561 (list htop vim emacs)
39564 The same approach as @code{simple-service} (@pxref{Service Reference,
39565 simple-service}) for @code{home-environment-variables-service-type} can
39566 be used here, too. Make sure that modules containing the specified
39567 packages are imported with @code{use-modules}. To find a package or
39568 information about its module use @command{guix search} (@pxref{Invoking
39569 guix package}). Alternatively, @code{specification->package} can be
39570 used to get the package record from string without importing related
39574 There are few more essential services, but users are not expected to
39577 @defvr {Scheme Variable} home-service-type
39578 The root of home services DAG, it generates a folder, which later will be
39579 symlinked to @file{~/.guix-home}, it contains configurations,
39580 profile with binaries and libraries, and some necessary scripts to glue
39584 @defvr {Scheme Variable} home-run-on-first-login-service-type
39585 The service of this type generates a Guile script, which is expected to
39586 be executed by the login shell. It is only executed if the special flag
39587 file inside @env{XDG_RUNTIME_DIR} hasn't been created, this prevents
39588 redundant executions of the script if multiple login shells are spawned.
39590 It can be extended with a gexp. However, to autostart an application,
39591 users @emph{should not} use this service, in most cases it's better to extend
39592 @code{home-shepherd-service-type} with a Shepherd service
39593 (@pxref{Shepherd Services}), or extend the shell's startup file with
39594 the required command using the appropriate service type.
39597 @defvr {Scheme Variable} home-files-service-type
39598 The service of this type allows to specify a list of files, which will
39599 go to @file{~/.guix-home/files}, usually this directory contains
39600 configuration files (to be more precise it contains symlinks to files in
39601 @file{/gnu/store}), which should be placed in @file{$XDG_CONFIG_DIR} or
39602 in rare cases in @file{$HOME}. It accepts extension values in the
39606 `((".sway/config" ,sway-file-like-object)
39607 (".tmux.conf" ,(local-file "./tmux.conf")))
39610 Each nested list contains two values: a subdirectory and file-like
39611 object. After building a home environment @file{~/.guix-home/files}
39612 will be populated with apropiate content and all nested directories will
39613 be created accordingly, however, those files won't go any further until
39614 some other service will do it. By default a
39615 @code{home-symlink-manager-service-type}, which creates necessary
39616 symlinks in home folder to files from @file{~/.guix-home/files} and
39617 backs up already existing, but clashing configs and other things, is a
39618 part of essential home services (enabled by default), but it's possible
39619 to use alternative services to implement more advanced use cases like
39620 read-only home. Feel free to experiment and share your results.
39623 @defvr {Scheme Variable} home-xdg-configuration-files-service-type
39624 The service is very similiar to @code{home-files-service-type} (and
39625 actually extends it), but used for defining files, which will go to
39626 @file{~/.guix-home/files/.config}, which will be symlinked to
39627 @file{$XDG_CONFIG_DIR} by @code{home-symlink-manager-service-type} (for
39628 example) during activation. It accepts extension values in the
39632 `(("sway/config" ,sway-file-like-object)
39633 ;; -> ~/.guix-home/files/.config/sway/config
39634 ;; -> $XDG_CONFIG_DIR/sway/config (by symlink-manager)
39635 ("tmux/tmux.conf" ,(local-file "./tmux.conf")))
39639 @defvr {Scheme Variable} home-activation-service-type
39640 The service of this type generates a guile script, which runs on every
39641 @command{guix home reconfigure} invocation or any other action, which
39642 leads to the activation of the home environment.
39645 @defvr {Scheme Variable} home-symlink-manager-service-type
39646 The service of this type generates a guile script, which will be
39647 executed during activation of home environment, and do a few following
39652 Reads the content of @file{files/} directory of current and pending home
39656 Cleans up all symlinks created by symlink-manager on previous
39657 activation. Also, sub-directories, which become empty also will be
39661 Creates new symlinks the following way: It looks @file{files/} directory
39662 (usually defined with @code{home-files-service-type},
39663 @code{home-xdg-configuration-files-service-type} and maybe some others),
39664 takes the files from @file{files/.config/} subdirectory and put
39665 respective links in @env{XDG_CONFIG_DIR}. For example symlink for
39666 @file{files/.config/sway/config} will end up in
39667 @file{$XDG_CONFIG_DIR/sway/config}. The rest files in @file{files/}
39668 outside of @file{files/.config/} subdirectory will be treated slightly
39669 different: symlink will just go to @file{$HOME}.
39670 @file{files/.some-program/config} will end up in
39671 @file{$HOME/.some-program/config}.
39674 If some sub-directories are missing, they will be created.
39677 If there is a clashing files on the way, they will be backed up.
39681 symlink-manager is a part of essential home services and is enabled and
39686 @node Shells Home Services
39690 @cindex login shell
39691 @cindex interactive shell
39695 Shells play a quite important role in the environment initialization
39696 process, you can configure them manually as described in section
39697 @ref{Configuring the Shell}, but the recommended way is to use home services
39698 listed below. It's both easier and more reliable.
39700 Each home environment instantiates
39701 @code{home-shell-profile-service-type}, which creates a
39702 @file{~/.profile} startup file for all POSIX-compatible shells. This
39703 file contains all the necessary steps to properly initialize the
39704 environment, but many modern shells like Bash or Zsh prefer their own
39705 startup files, that's why the respective home services
39706 (@code{home-bash-service-type} and @code{home-zsh-service-type}) ensure
39707 that @file{~/.profile} is sourced by @file{~/.bash_profile} and
39708 @file{~/.zprofile}, respectively.
39710 @subsubheading Shell Profile Service
39712 @deftp {Data Type} home-shell-profile-configuration
39713 Available @code{home-shell-profile-configuration} fields are:
39716 @item @code{profile} (default: @code{()}) (type: text-config)
39717 @code{home-shell-profile} is instantiated automatically by
39718 @code{home-environment}, DO NOT create this service manually, it can
39719 only be extended. @code{profile} is a list of file-like objects, which
39720 will go to @file{~/.profile}. By default @file{~/.profile} contains the
39721 initialization code which must be evaluated by the login shell to make
39722 home-environment's profile available to the user, but other commands can
39723 be added to the file if it is really necessary. In most cases shell's
39724 configuration files are preferred places for user's customizations.
39725 Extend home-shell-profile service only if you really know what you do.
39731 @subsubheading Bash Home Service
39733 @anchor{home-bash-configuration}
39734 @deftp {Data Type} home-bash-configuration
39735 Available @code{home-bash-configuration} fields are:
39738 @item @code{package} (default: @code{bash}) (type: package)
39739 The Bash package to use.
39741 @item @code{guix-defaults?} (default: @code{#t}) (type: boolean)
39742 Add sane defaults like reading @file{/etc/bashrc} and coloring the output of
39743 @command{ls} to the top of the @file{.bashrc} file.
39745 @item @code{environment-variables} (default: @code{()}) (type: alist)
39746 Association list of environment variables to set for the Bash session. The
39747 rules for the @code{home-environment-variables-service-type} apply
39748 here (@pxref{Essential Home Services}). The contents of this field will be
39749 added after the contents of the @code{bash-profile} field.
39751 @item @code{aliases} (default: @code{()}) (type: alist)
39752 Association list of aliases to set for the Bash session. The aliases
39753 will be defined after the contents of the @code{bashrc} field has been
39754 put in the @file{.bashrc} file. The alias will automatically be quoted,
39755 so something like this:
39758 '(("ls" . "ls -alF"))
39767 @item @code{bash-profile} (default: @code{()}) (type: text-config)
39768 List of file-like objects, which will be added to @file{.bash_profile}.
39769 Used for executing user's commands at start of login shell (In most
39770 cases the shell started on tty just after login). @file{.bash_login}
39771 won't be ever read, because @file{.bash_profile} always present.
39773 @item @code{bashrc} (default: @code{()}) (type: text-config)
39774 List of file-like objects, which will be added to @file{.bashrc}. Used
39775 for executing user's commands at start of interactive shell (The shell
39776 for interactive usage started by typing @code{bash} or by terminal app
39777 or any other program).
39779 @item @code{bash-logout} (default: @code{()}) (type: text-config)
39780 List of file-like objects, which will be added to @file{.bash_logout}.
39781 Used for executing user's commands at the exit of login shell. It won't
39782 be read in some cases (if the shell terminates by exec'ing another
39783 process for example).
39788 You can extend the Bash service by using the @code{home-bash-extension}
39789 configuration record, whose fields must mirror that of
39790 @code{home-bash-configuration} (@pxref{home-bash-configuration}). The
39791 contents of the extensions will be added to the end of the corresponding
39792 Bash configuration files (@pxref{Bash Startup Files,,, bash, The GNU
39793 Bash Reference Manual}.
39795 For example, here is how you would define a service that extends the
39796 Bash service such that @file{~/.bash_profile} defines an additional
39797 environment variable, @env{PS1}:
39800 (define bash-fancy-prompt-service
39801 (simple-service 'bash-fancy-prompt
39802 home-bash-service-type
39803 (home-bash-extension
39804 (environment-variables
39805 '(("PS1" . "\\u \\wλ "))))))
39808 You would then add @code{bash-fancy-prompt-service} to the list in the
39809 @code{services} field of your @code{home-environment}. The reference of
39810 @code{home-bash-extension} follows.
39812 @deftp {Data Type} home-bash-extension
39813 Available @code{home-bash-extension} fields are:
39816 @item @code{environment-variables} (default: @code{()}) (type: alist)
39817 Additional environment variables to set. These will be combined with the
39818 environment variables from other extensions and the base service to form one
39819 coherent block of environment variables.
39821 @item @code{aliases} (default: @code{()}) (type: alist)
39822 Additional aliases to set. These will be combined with the aliases from
39823 other extensions and the base service.
39825 @item @code{bash-profile} (default: @code{()}) (type: text-config)
39826 Additional text blocks to add to @file{.bash_profile}, which will be combined
39827 with text blocks from other extensions and the base service.
39829 @item @code{bashrc} (default: @code{()}) (type: text-config)
39830 Additional text blocks to add to @file{.bashrc}, which will be combined
39831 with text blocks from other extensions and the base service.
39833 @item @code{bash-logout} (default: @code{()}) (type: text-config)
39834 Additional text blocks to add to @file{.bash_logout}, which will be combined
39835 with text blocks from other extensions and the base service.
39840 @subsubheading Zsh Home Service
39842 @deftp {Data Type} home-zsh-configuration
39843 Available @code{home-zsh-configuration} fields are:
39846 @item @code{package} (default: @code{zsh}) (type: package)
39847 The Zsh package to use.
39849 @item @code{xdg-flavor?} (default: @code{#t}) (type: boolean)
39850 Place all the configs to @file{$XDG_CONFIG_HOME/zsh}. Makes
39851 @file{~/.zshenv} to set @env{ZDOTDIR} to @file{$XDG_CONFIG_HOME/zsh}.
39852 Shell startup process will continue with
39853 @file{$XDG_CONFIG_HOME/zsh/.zshenv}.
39855 @item @code{environment-variables} (default: @code{()}) (type: alist)
39856 Association list of environment variables to set for the Zsh session.
39858 @item @code{zshenv} (default: @code{()}) (type: text-config)
39859 List of file-like objects, which will be added to @file{.zshenv}. Used
39860 for setting user's shell environment variables. Must not contain
39861 commands assuming the presence of tty or producing output. Will be read
39862 always. Will be read before any other file in @env{ZDOTDIR}.
39864 @item @code{zprofile} (default: @code{()}) (type: text-config)
39865 List of file-like objects, which will be added to @file{.zprofile}. Used
39866 for executing user's commands at start of login shell (In most cases the
39867 shell started on tty just after login). Will be read before
39870 @item @code{zshrc} (default: @code{()}) (type: text-config)
39871 List of file-like objects, which will be added to @file{.zshrc}. Used
39872 for executing user's commands at start of interactive shell (The shell
39873 for interactive usage started by typing @code{zsh} or by terminal app or
39874 any other program).
39876 @item @code{zlogin} (default: @code{()}) (type: text-config)
39877 List of file-like objects, which will be added to @file{.zlogin}. Used
39878 for executing user's commands at the end of starting process of login
39881 @item @code{zlogout} (default: @code{()}) (type: text-config)
39882 List of file-like objects, which will be added to @file{.zlogout}. Used
39883 for executing user's commands at the exit of login shell. It won't be
39884 read in some cases (if the shell terminates by exec'ing another process
39891 @node Mcron Home Service
39892 @subsection Scheduled User's Job Execution
39896 @cindex scheduling jobs
39898 The @code{(gnu home services mcron)} module provides an interface to
39899 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
39900 mcron, GNU@tie{}mcron}). The information about system's mcron is
39901 applicable here (@pxref{Scheduled Job Execution}), the only difference
39902 for home services is that they have to be declared in a
39903 @code{home-environment} record instead of an @code{operating-system}
39906 @defvr {Scheme Variable} home-mcron-service-type
39907 This is the type of the @code{mcron} home service, whose value is an
39908 @code{home-mcron-configuration} object. It allows to manage scheduled
39911 This service type can be the target of a service extension that provides
39912 additional job specifications (@pxref{Service Composition}). In other
39913 words, it is possible to define services that provide additional mcron
39917 @deftp {Data Type} home-mcron-configuration
39918 Data type representing the configuration of mcron.
39921 @item @code{mcron} (default: @var{mcron})
39922 The mcron package to use.
39925 This is a list of gexps (@pxref{G-Expressions}), where each gexp
39926 corresponds to an mcron job specification (@pxref{Syntax, mcron job
39927 specifications,, mcron, GNU@tie{}mcron}).
39931 @node Shepherd Home Service
39932 @subsection Managing User Daemons
39934 @cindex shepherd services, for users
39935 The @code{(gnu home services shepherd)} module supports the definitions
39936 of per-user Shepherd services (@pxref{Introduction,,, shepherd, The GNU
39937 Shepherd Manual}). You extend @code{home-shepherd-service-type} with
39938 new services; Guix Home then takes care of starting the @code{shepherd}
39939 daemon for you when you log in, which in turns starts the services you
39942 @defvr {Scheme Variable} home-shepherd-service-type
39943 The service type for the userland Shepherd, which allows one to manage
39944 long-running processes or one-shot tasks. User's Shepherd is not an
39945 init process (PID 1), but almost all other information described in
39946 (@pxref{Shepherd Services}) is applicable here too.
39948 This is the service type that extensions target when they want to create
39949 shepherd services (@pxref{Service Types and Services}, for an example).
39950 Each extension must pass a list of @code{<shepherd-service>}. Its
39951 value must be a @code{home-shepherd-configuration}, as described below.
39954 @deftp {Data Type} home-shepherd-configuration
39955 This data type represents the Shepherd's configuration.
39958 @item shepherd (default: @code{shepherd})
39959 The Shepherd package to use.
39961 @item auto-start? (default: @code{#t})
39962 Whether or not to start Shepherd on first login.
39964 @item services (default: @code{'()})
39965 A list of @code{<shepherd-service>} to start.
39966 You should probably use the service extension
39967 mechanism instead (@pxref{Shepherd Services}).
39972 @subsection Secure Shell
39974 @cindex secure shell client, configuration
39975 @cindex SSH client, configuration
39976 The @uref{https://www.openssh.com, OpenSSH package} includes a client,
39977 the @command{ssh} command, that allows you to connect to remote machines
39978 using the @acronym{SSH, secure shell} protocol. With the @code{(gnu
39979 home services ssh)} module, you can set up OpenSSH so that it works in a
39980 predictable fashion, almost independently of state on the local machine.
39981 To do that, you instantiate @code{home-openssh-service-type} in your
39982 Home configuration, as explained below.
39984 @defvr {Scheme Variable} home-openssh-service-type
39985 This is the type of the service to set up the OpenSSH client. It takes
39986 care of several things:
39990 providing a @file{~/.ssh/config} file based on your configuration so
39991 that @command{ssh} knows about hosts you regularly connect to and their
39992 associated parameters;
39995 providing a @file{~/.ssh/authorized_keys}, which lists public keys that
39996 the local SSH server, @command{sshd}, may accept to connect to this user
40000 optionally providing a @file{~/.ssh/known_hosts} file so that @file{ssh}
40001 can authenticate hosts you connect to.
40004 Here is an example of a service and its configuration that you could add
40005 to the @code{services} field of your @code{home-environment}:
40008 (service home-openssh-service-type
40009 (home-openssh-configuration
40011 (list (openssh-host (name "ci.guix.gnu.org")
40013 (openssh-host (name "chbouib")
40014 (host-name "chbouib.example.org")
40015 (user "supercharlie")
40017 (authorized-keys (list (local-file "alice.pub")))))
40020 The example above lists two hosts and their parameters. For instance,
40021 running @command{ssh chbouib} will automatically connect to
40022 @code{chbouib.example.org} on port 10022, logging in as user
40023 @samp{supercharlie}. Further, it marks the public key in
40024 @file{alice.pub} as authorized for incoming connections.
40026 The value associated with a @code{home-openssh-service-type} instance
40027 must be a @code{home-openssh-configuration} record, as describe below.
40030 @deftp {Data Type} home-openssh-configuration
40031 This is the datatype representing the OpenSSH client and server
40032 configuration in one's home environment. It contains the following
40036 @item @code{hosts} (default: @code{'()})
40037 A list of @code{openssh-host} records specifying host names and
40038 associated connection parameters (see below). This host list goes into
40039 @file{~/.ssh/config}, which @command{ssh} reads at startup.
40041 @item @code{known-hosts} (default: @code{*unspecified*})
40042 This must be either:
40046 @code{*unspecified*}, in which case @code{home-openssh-service-type}
40047 leaves it up to @command{ssh} and to the user to maintain the list of
40048 known hosts at @file{~/.ssh/known_hosts}, or
40051 a list of file-like objects, in which case those are concatenated and
40052 emitted as @file{~/.ssh/known_hosts}.
40055 The @file{~/.ssh/known_hosts} contains a list of host name/host key
40056 pairs that allow @command{ssh} to authenticate hosts you connect to and
40057 to detect possible impersonation attacks. By default, @command{ssh}
40058 updates it in a @dfn{TOFU, trust-on-first-use} fashion, meaning that it
40059 records the host's key in that file the first time you connect to it.
40060 This behavior is preserved when @code{known-hosts} is set to
40061 @code{*unspecified*}.
40063 If you instead provide a list of host keys upfront in the
40064 @code{known-hosts} field, your configuration becomes self-contained and
40065 stateless: it can be replicated elsewhere or at another point in time.
40066 Preparing this list can be relatively tedious though, which is why
40067 @code{*unspecified*} is kept as a default.
40069 @item @code{authorized-keys} (default: @code{'()})
40070 This must be a list of file-like objects, each of which containing an
40071 SSH public key that should be authorized to connect to this machine.
40073 Concretely, these files are concatenated and made available as
40074 @file{~/.ssh/authorized_keys}. If an OpenSSH server, @command{sshd}, is
40075 running on this machine, then it @emph{may} take this file into account:
40076 this is what @command{sshd} does by default, but be aware that it can
40077 also be configured to ignore it.
40081 @c %start of fragment
40083 @deftp {Data Type} openssh-host
40084 Available @code{openssh-host} fields are:
40087 @item @code{name} (type: string)
40088 Name of this host declaration.
40090 @item @code{host-name} (type: maybe-string)
40091 Host name---e.g., @code{"foo.example.org"} or @code{"192.168.1.2"}.
40093 @item @code{address-family} (type: address-family)
40094 Address family to use when connecting to this host: one of
40095 @code{AF_INET} (for IPv4 only), @code{AF_INET6} (for IPv6 only), or
40096 @code{*unspecified*} (allowing any address family).
40098 @item @code{identity-file} (type: maybe-string)
40099 The identity file to use---e.g., @code{"/home/charlie/.ssh/id_ed25519"}.
40101 @item @code{port} (type: maybe-natural-number)
40102 TCP port number to connect to.
40104 @item @code{user} (type: maybe-string)
40105 User name on the remote host.
40107 @item @code{forward-x11?} (default: @code{#f}) (type: boolean)
40108 Whether to forward remote client connections to the local X11 graphical
40111 @item @code{forward-x11-trusted?} (default: @code{#f}) (type: boolean)
40112 Whether remote X11 clients have full access to the original X11
40115 @item @code{forward-agent?} (default: @code{#f}) (type: boolean)
40116 Whether the authentication agent (if any) is forwarded to the remote
40119 @item @code{compression?} (default: @code{#f}) (type: boolean)
40120 Whether to compress data in transit.
40122 @item @code{proxy-command} (type: maybe-string)
40123 The command to use to connect to the server. As an example, a command
40124 to connect via an HTTP proxy at 192.0.2.0 would be: @code{"nc -X connect
40125 -x 192.0.2.0:8080 %h %p"}.
40127 @item @code{host-key-algorithms} (type: maybe-string-list)
40128 The list of accepted host key algorithms---e.g.,
40129 @code{'("ssh-ed25519")}.
40131 @item @code{accepted-key-types} (type: maybe-string-list)
40132 The list of accepted user public key types.
40134 @item @code{extra-content} (default: @code{""}) (type: raw-configuration-string)
40135 Extra content appended as-is to this @code{Host} block in
40136 @file{~/.ssh/config}.
40143 @c %end of fragment
40146 @node Desktop Home Services
40147 @subsection Desktop Home Services
40149 The @code{(gnu home services desktop)} module provides services that you
40150 may find useful on ``desktop'' systems running a graphical user
40151 environment such as Xorg.
40153 @defvr {Scheme Variable} home-redshift-service-type
40154 This is the service type for @uref{https://github.com/jonls/redshift,
40155 Redshift}, a program that adjusts the display color temperature
40156 according to the time of day. Its associated value must be a
40157 @code{home-redshift-configuration} record, as shown below.
40159 A typical configuration, where we manually specify the latitude and
40160 longitude, might look like this:
40163 (service home-redshift-service-type
40164 (home-redshift-configuration
40165 (location-provider 'manual)
40166 (latitude 35.81) ;northern hemisphere
40167 (longitude -0.80))) ;west of Greenwich
40171 @deftp {Data Type} home-redshift-configuration
40172 Available @code{home-redshift-configuration} fields are:
40175 @item @code{redshift} (default: @code{redshift}) (type: file-like)
40176 Redshift package to use.
40178 @item @code{location-provider} (default: @code{geoclue2}) (type: symbol)
40179 Geolocation provider---@code{'manual} or @code{'geoclue2}. In the
40180 former case, you must also specify the @code{latitude} and
40181 @code{longitude} fields so Redshift can determine daytime at your place.
40182 In the latter case, the Geoclue system service must be running; it will
40183 be queried for location information.
40185 @item @code{adjustment-method} (default: @code{randr}) (type: symbol)
40186 Color adjustment method.
40188 @item @code{daytime-temperature} (default: @code{6500}) (type: integer)
40189 Daytime color temperature (kelvins).
40191 @item @code{nighttime-temperature} (default: @code{4500}) (type: integer)
40192 Nighttime color temperature (kelvins).
40194 @item @code{daytime-brightness} (type: maybe-inexact-number)
40195 Daytime screen brightness, between 0.1 and 1.0, or left unspecified.
40197 @item @code{nighttime-brightness} (type: maybe-inexact-number)
40198 Nighttime screen brightness, between 0.1 and 1.0, or left unspecified.
40200 @item @code{latitude} (type: maybe-inexact-number)
40201 Latitude, when @code{location-provider} is @code{'manual}.
40203 @item @code{longitude} (type: maybe-inexact-number)
40204 Longitude, when @code{location-provider} is @code{'manual}.
40206 @item @code{dawn-time} (type: maybe-string)
40207 Custom time for the transition from night to day in the
40208 morning---@code{"HH:MM"} format. When specified, solar elevation is not
40209 used to determine the daytime/nighttime period.
40211 @item @code{dusk-time} (type: maybe-string)
40212 Likewise, custom time for the transition from day to night in the
40215 @item @code{extra-content} (default: @code{""}) (type: raw-configuration-string)
40216 Extra content appended as-is to the Redshift configuration file. Run
40217 @command{man redshift} for more information about the configuration file
40224 @node Guix Home Services
40225 @subsection Guix Home Services
40227 The @code{(gnu home services guix)} module provides services for
40228 user-specific Guix configuration.
40230 @defvr {Scheme Variable} home-channels-service-type
40231 This is the service type for managing
40232 @file{$XDG_CONFIG_HOME/guix/channels.scm}, the file that controls the
40233 channels received on @command{guix pull} (@pxref{Channels}). Its
40234 associated value is a list of @code{channel} records, defined in the
40235 @code{(guix channels)} module.
40237 Generally, it is better to extend this service than to directly
40238 configure it, as its default value is the default guix channel(s)
40239 defined by @code{%default-channels}. If you configure this service
40240 directly, be sure to include a guix channel. @xref{Specifying
40241 Additional Channels} and @ref{Using a Custom Guix Channel} for more
40244 A typical extension for adding a channel might look like this:
40247 (simple-service 'variant-packages-service
40248 home-channels-service-type
40251 (name 'variant-packages)
40252 (url "https://example.org/variant-packages.git")))
40256 @node Invoking guix home
40257 @section Invoking @code{guix home}
40259 Once you have written a home environment declaration (@pxref{Declaring
40260 the Home Environment,,,,}, it can be @dfn{instantiated} using the
40261 @command{guix home} command. The synopsis is:
40264 guix home @var{options}@dots{} @var{action} @var{file}
40267 @var{file} must be the name of a file containing a
40268 @code{home-environment} declaration. @var{action} specifies how the
40269 home environment is instantiated, but there are few auxiliary actions
40270 which don't instantiate it. Currently the following values are
40275 Display available home service type definitions that match the given
40276 regular expressions, sorted by relevance:
40279 @cindex shell-profile
40283 $ guix home search shell
40284 name: home-shell-profile
40285 location: gnu/home/services/shells.scm:100:2
40286 extends: home-files
40287 description: Create `~/.profile', which is used for environment initialization of POSIX compliant login shells.
40288 + This service type can be extended with a list of file-like objects.
40292 location: gnu/home/services/shells.scm:640:2
40293 extends: home-files home-profile
40294 description: Install and configure Fish, the friendly interactive shell.
40298 location: gnu/home/services/shells.scm:290:2
40299 extends: home-files home-profile
40300 description: Install and configure Zsh.
40304 location: gnu/home/services/shells.scm:508:2
40305 extends: home-files home-profile
40306 description: Install and configure GNU Bash.
40312 As for @command{guix search}, the result is written in
40313 @code{recutils} format, which makes it easy to filter the output
40314 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
40316 @cindex container, for @command{guix home}
40318 Spawn a shell in an isolated environment---a
40319 @dfn{container}---containing your home as specified by @var{file}.
40321 For example, this is how you would start an interactive shell in a
40322 container with your home:
40325 guix home container config.scm
40328 This is a throw-away container where you can lightheartedly fiddle with
40329 files; any changes made within the container, any process started---all
40330 this disappears as soon as you exit that shell.
40332 As with @command{guix shell}, several options control that container:
40337 Enable networking within the container (it is disabled by default).
40339 @item --expose=@var{source}[=@var{target}]
40340 @itemx --share=@var{source}[=@var{target}]
40341 As with @command{guix shell}, make directory @var{source} of the host
40342 system available as @var{target} inside the container---read-only if you
40343 pass @option{--expose}, and writable if you pass @option{--share}
40344 (@pxref{Invoking guix shell, @option{--expose} and @option{--share}}).
40347 Additionally, you can run a command in that container, instead of
40348 spawning an interactive shell. For instance, here is how you would
40349 check which Shepherd services are started in a throw-away home
40353 guix home container config.scm -- herd status
40356 The command to run in the container must come after @code{--} (double
40359 @cindex service type definition, editing
40360 @cindex editing, service type definition
40362 Edit or view the definition of the given Home service types.
40364 For example, the command below opens your editor, as specified by the
40365 @env{EDITOR} environment variable, on the definition of the
40366 @code{home-mcron} service type:
40369 guix home edit home-mcron
40373 Build the home environment described in @var{file}, and switch to it.
40374 Switching means that the activation script will be evaluated and (in
40375 basic scenario) symlinks to configuration files generated from
40376 @code{home-environment} declaration will be created in @file{~}. If the
40377 file with the same path already exists in home folder it will be moved
40378 to @file{~/@var{timestamp}-guix-home-legacy-configs-backup}, where @var{timestamp}
40379 is a current UNIX epoch time.
40382 It is highly recommended to run @command{guix pull} once before you run
40383 @command{guix home reconfigure} for the first time (@pxref{Invoking guix
40387 This effects all the configuration specified in @var{file}. The command
40388 starts Shepherd services specified in @var{file} that are not currently
40389 running; if a service is currently running, this command will arrange
40390 for it to be upgraded the next time it is stopped (e.g.@: by @code{herd
40391 stop @var{service}} or @code{herd restart @var{service}}).
40393 This command creates a new generation whose number is one greater than
40394 the current generation (as reported by @command{guix home
40395 list-generations}). If that generation already exists, it will be
40396 overwritten. This behavior mirrors that of @command{guix package}
40397 (@pxref{Invoking guix package}).
40399 @cindex provenance tracking, of the home environment
40400 Upon completion, the new home is deployed under @file{~/.guix-home}.
40401 This directory contains @dfn{provenance meta-data}: the list of channels
40402 in use (@pxref{Channels}) and @var{file} itself, when available. You
40403 can view the provenance information by running:
40409 This information is useful should you later want to inspect how this
40410 particular generation was built. In fact, assuming @var{file} is
40411 self-contained, you can later rebuild generation @var{n} of your
40412 home environment with:
40415 guix time-machine \
40416 -C /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/channels.scm -- \
40418 /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/configuration.scm
40422 You can think of it as some sort of built-in version control! Your
40423 home is not just a binary artifact: @emph{it carries its own source}.
40424 @c @xref{Service Reference, @code{provenance-service-type}}, for more
40425 @c information on provenance tracking.
40427 @c @footnote{This action (and the related actions
40428 @c @code{switch-generation} and @code{roll-back}) are usable after the
40429 @c home environment is initialized.}.
40431 @item switch-generation
40432 @cindex home generations
40433 Switch to an existing home generation. This action atomically switches
40434 the home profile to the specified home generation.
40436 The target generation can be specified explicitly by its generation
40437 number. For example, the following invocation would switch to home
40441 guix home switch-generation 7
40444 The target generation can also be specified relative to the current
40445 generation with the form @code{+N} or @code{-N}, where @code{+3} means
40446 ``3 generations ahead of the current generation,'' and @code{-1} means
40447 ``1 generation prior to the current generation.'' When specifying a
40448 negative value such as @code{-1}, you must precede it with @code{--} to
40449 prevent it from being parsed as an option. For example:
40452 guix home switch-generation -- -1
40455 This action will fail if the specified generation does not exist.
40458 @cindex rolling back
40459 Switch to the preceding home generation. This is the inverse
40460 of @command{reconfigure}, and it is exactly the same as invoking
40461 @command{switch-generation} with an argument of @code{-1}.
40463 @item delete-generations
40464 @cindex deleting home generations
40465 @cindex saving space
40466 Delete home generations, making them candidates for garbage collection
40467 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
40470 This works in the same way as @samp{guix package --delete-generations}
40471 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
40472 arguments, all home generations but the current one are deleted:
40475 guix home delete-generations
40478 You can also select the generations you want to delete. The example below
40479 deletes all the home generations that are more than two months old:
40482 guix home delete-generations 2m
40486 Build the derivation of the home environment, which includes all the
40487 configuration files and programs needed. This action does not actually
40491 Describe the current home generation: its file name, as well as
40492 provenance information when available.
40494 To show installed packages in the current home generation's profile, the
40495 @code{--list-installed} flag is provided, with the same syntax that is
40496 used in @command{guix package --list-installed} (@pxref{Invoking guix
40497 package}). For instance, the following command shows a table of all the
40498 packages with ``emacs'' in their name that are installed in the current
40499 home generation's profile:
40502 guix home describe --list-installed=emacs
40505 @item list-generations
40506 List a summary of each generation of the home environment available on
40507 disk, in a human-readable way. This is similar to the
40508 @option{--list-generations} option of @command{guix package}
40509 (@pxref{Invoking guix package}).
40511 Optionally, one can specify a pattern, with the same syntax that is used
40512 in @command{guix package --list-generations}, to restrict the list of
40513 generations displayed. For instance, the following command displays
40514 generations that are up to 10 days old:
40517 guix home list-generations 10d
40520 The @code{--list-installed} flag may also be specified, with the same
40521 syntax that is used in @command{guix home describe}. This may be
40522 helpful if trying to determine when a package was added to the home
40526 Generate a @dfn{home environment} from the packages in the default
40527 profile and configuration files found in the user's home directory. The
40528 configuration files will be copied to the specified directory, and a
40529 @file{home-configuration.scm} will be populated with the home
40530 environment. Note that not every home service that exists is supported
40531 (@pxref{Home Services}).
40534 $ guix home import ~/guix-config
40535 guix home: '/home/alice/guix-config' populated with all the Home configuration files
40539 And there's more! @command{guix home} also provides the following
40540 sub-commands to visualize how the services of your home environment
40541 relate to one another:
40544 @cindex service extension graph, of a home environment
40545 @item extension-graph
40546 Emit to standard output the @dfn{service extension graph} of the home
40547 environment defined in @var{file} (@pxref{Service Composition}, for more
40548 information on service extensions). By default the output is in
40549 Dot/Graphviz format, but you can choose a different format with
40550 @option{--graph-backend}, as with @command{guix graph} (@pxref{Invoking
40551 guix graph, @option{--backend}}):
40556 guix home extension-graph @var{file} | xdot -
40559 shows the extension relations among services.
40561 @cindex Shepherd dependency graph, for a home environment
40562 @item shepherd-graph
40563 Emit to standard output the @dfn{dependency graph} of shepherd services
40564 of the home environment defined in @var{file}. @xref{Shepherd
40565 Services}, for more information and for an example graph.
40567 Again, the default output format is Dot/Graphviz, but you can pass
40568 @option{--graph-backend} to select a different one.
40571 @var{options} can contain any of the common build options (@pxref{Common
40572 Build Options}). In addition, @var{options} can contain one of the
40577 @item --expression=@var{expr}
40578 @itemx -e @var{expr}
40579 Consider the home-environment @var{expr} evaluates to.
40580 This is an alternative to specifying a file which evaluates to a home
40583 @item --allow-downgrades
40584 Instruct @command{guix home reconfigure} to allow system downgrades.
40586 Just like @command{guix system}, @command{guix home reconfigure}, by
40587 default, prevents you from downgrading your home to older or unrelated
40588 revisions compared to the channel revisions that were used to deploy
40589 it---those shown by @command{guix home describe}. Using
40590 @option{--allow-downgrades} allows you to bypass that check, at the risk
40591 of downgrading your home---be careful!
40595 @node Documentation
40596 @chapter Documentation
40598 @cindex documentation, searching for
40599 @cindex searching for documentation
40600 @cindex Info, documentation format
40602 @cindex manual pages
40603 In most cases packages installed with Guix come with documentation.
40604 There are two main documentation formats: ``Info'', a browsable
40605 hypertext format used for GNU software, and ``manual pages'' (or ``man
40606 pages''), the linear documentation format traditionally found on Unix.
40607 Info manuals are accessed with the @command{info} command or with Emacs,
40608 and man pages are accessed using @command{man}.
40610 You can look for documentation of software installed on your system by
40611 keyword. For example, the following command searches for information
40612 about ``TLS'' in Info manuals:
40616 "(emacs)Network Security" -- STARTTLS
40617 "(emacs)Network Security" -- TLS
40618 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
40619 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
40624 The command below searches for the same keyword in man
40625 pages@footnote{The database searched by @command{man -k} is only created
40626 in profiles that contain the @code{man-db} package.}:
40630 SSL (7) - OpenSSL SSL/TLS library
40631 certtool (1) - GnuTLS certificate tool
40635 These searches are purely local to your computer so you have the
40636 guarantee that documentation you find corresponds to what you have
40637 actually installed, you can access it off-line, and your privacy is
40640 Once you have these results, you can view the relevant documentation by
40644 $ info "(gnutls)Core TLS API"
40654 Info manuals contain sections and indices as well as hyperlinks like
40655 those found in Web pages. The @command{info} reader (@pxref{Top, Info
40656 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
40657 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
40658 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
40659 Introduction}, for an introduction to Info navigation.
40661 @node Installing Debugging Files
40662 @chapter Installing Debugging Files
40664 @cindex debugging files
40665 Program binaries, as produced by the GCC compilers for instance, are
40666 typically written in the ELF format, with a section containing
40667 @dfn{debugging information}. Debugging information is what allows the
40668 debugger, GDB, to map binary code to source code; it is required to
40669 debug a compiled program in good conditions.
40671 This chapter explains how to use separate debug info when packages
40672 provide it, and how to rebuild packages with debug info when it's
40676 * Separate Debug Info:: Installing 'debug' outputs.
40677 * Rebuilding Debug Info:: Building missing debug info.
40680 @node Separate Debug Info
40681 @section Separate Debug Info
40683 The problem with debugging information is that is takes up a fair amount
40684 of disk space. For example, debugging information for the GNU C Library
40685 weighs in at more than 60 MiB@. Thus, as a user, keeping all the
40686 debugging info of all the installed programs is usually not an option.
40687 Yet, space savings should not come at the cost of an impediment to
40688 debugging---especially in the GNU system, which should make it easier
40689 for users to exert their computing freedom (@pxref{GNU Distribution}).
40691 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
40692 mechanism that allows users to get the best of both worlds: debugging
40693 information can be stripped from the binaries and stored in separate
40694 files. GDB is then able to load debugging information from those files,
40695 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
40698 The GNU distribution takes advantage of this by storing debugging
40699 information in the @code{lib/debug} sub-directory of a separate package
40700 output unimaginatively called @code{debug} (@pxref{Packages with
40701 Multiple Outputs}). Users can choose to install the @code{debug} output
40702 of a package when they need it. For instance, the following command
40703 installs the debugging information for the GNU C Library and for GNU
40707 guix install glibc:debug guile:debug
40710 GDB must then be told to look for debug files in the user's profile, by
40711 setting the @code{debug-file-directory} variable (consider setting it
40712 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
40716 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
40719 From there on, GDB will pick up debugging information from the
40720 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
40722 Below is an alternative GDB script which is useful when working with
40723 other profiles. It takes advantage of the optional Guile integration in
40724 GDB. This snippet is included by default on Guix System in the
40725 @file{~/.gdbinit} file.
40729 (use-modules (gdb))
40730 (execute (string-append "set debug-file-directory "
40731 (or (getenv "GDB_DEBUG_FILE_DIRECTORY")
40732 "~/.guix-profile/lib/debug")))
40736 In addition, you will most likely want GDB to be able to show the source
40737 code being debugged. To do that, you will have to unpack the source
40738 code of the package of interest (obtained with @code{guix build
40739 --source}, @pxref{Invoking guix build}), and to point GDB to that source
40740 directory using the @code{directory} command (@pxref{Source Path,
40741 @code{directory},, gdb, Debugging with GDB}).
40743 @c XXX: keep me up-to-date
40744 The @code{debug} output mechanism in Guix is implemented by the
40745 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
40746 opt-in---debugging information is available only for the packages with
40747 definitions explicitly declaring a @code{debug} output. To check
40748 whether a package has a @code{debug} output, use @command{guix package
40749 --list-available} (@pxref{Invoking guix package}).
40751 Read on for how to deal with packages lacking a @code{debug} output.
40753 @node Rebuilding Debug Info
40754 @section Rebuilding Debug Info
40756 @cindex debugging info, rebuilding
40757 As we saw above, some packages, but not all, provide debugging info in a
40758 @code{debug} output. What can you do when debugging info is missing?
40759 The @option{--with-debug-info} option provides a solution to that: it
40760 allows you to rebuild the package(s) for which debugging info is
40761 missing---and only those---and to graft those onto the application
40762 you're debugging. Thus, while it's not as fast as installing a
40763 @code{debug} output, it is relatively inexpensive.
40765 Let's illustrate that. Suppose you're experiencing a bug in Inkscape
40766 and would like to see what's going on in GLib, a library that's deep
40767 down in its dependency graph. As it turns out, GLib does not have a
40768 @code{debug} output and the backtrace GDB shows is all sadness:
40772 #0 0x00007ffff5f92190 in g_getenv ()
40773 from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
40774 #1 0x00007ffff608a7d6 in gobject_init_ctor ()
40775 from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
40776 #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
40777 env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
40778 #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
40782 To address that, you install Inkscape linked against a variant GLib that
40783 contains debug info:
40786 guix install inkscape --with-debug-info=glib
40789 This time, debugging will be a whole lot nicer:
40792 $ gdb --args sh -c 'exec inkscape'
40795 Function "g_getenv" not defined.
40796 Make breakpoint pending on future shared library load? (y or [n]) y
40797 Breakpoint 1 (g_getenv) pending.
40799 Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
40802 #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
40803 #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
40804 #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
40805 #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
40806 env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
40812 Note that there can be packages for which @option{--with-debug-info}
40813 will not have the desired effect. @xref{Package Transformation Options,
40814 @option{--with-debug-info}}, for more information.
40816 @node Using TeX and LaTeX
40817 @chapter Using @TeX{} and @LaTeX{}
40819 @cindex @TeX{} packages
40820 @cindex @LaTeX{} packages
40821 Guix provides packages for the @TeX{}, @LaTeX{}, ConTeXt, LuaTeX, and
40822 related typesetting systems, taken from the
40823 @uref{https://www.tug.org/texlive/, @TeX{} Live distribution}. However,
40824 because @TeX{} Live is so huge and because finding your way in this maze
40825 is tricky, we thought that you, dear user, would welcome guidance on how
40826 to deploy the relevant packages so you can compile your @TeX{} and
40827 @LaTeX{} documents.
40829 @TeX{} Live currently comes in two flavors in Guix:
40833 The ``monolithic'' @code{texlive} package: it comes with @emph{every
40834 single @TeX{} Live package} (more than 7,000 of them), but it is huge
40835 (more than 4@tie{}GiB for a single package!).
40838 The ``modular'' @code{texlive-} packages: you install
40839 @code{texlive-base}, which provides core functionality and the main
40840 commands---@command{pdflatex}, @command{dvips}, @command{luatex},
40841 @command{mf}, etc.---together with individual packages that provide just
40842 the features you need---@code{texlive-listings} for the
40843 @code{listings} package, @code{texlive-hyperref} for @code{hyperref},
40844 @code{texlive-beamer} for Beamer, @code{texlive-pgf} for PGF/TikZ,
40848 We recommend using the modular package set because it is much less
40849 resource-hungry. To build your documents, you would use commands such
40853 guix shell texlive-base texlive-wrapfig \
40854 texlive-hyperref texlive-cm-super -- pdflatex doc.tex
40857 You can quickly end up with unreasonably long command lines though. The
40858 solution is to instead write a manifest, for example like this one:
40861 (specifications->manifest
40867 "texlive-microtype"
40868 "texlive-listings" "texlive-hyperref"
40873 ;; Additional fonts.
40874 "texlive-cm-super" "texlive-amsfonts"
40875 "texlive-times" "texlive-helvetic" "texlive-courier"))
40878 You can then pass it to any command with the @option{-m} option:
40881 guix shell -m manifest.scm -- pdflatex doc.tex
40884 @xref{Writing Manifests}, for more on
40885 manifests. In the future, we plan to provide packages for @TeX{} Live
40886 @dfn{collections}---``meta-packages'' such as @code{fontsrecommended},
40887 @code{humanities}, or @code{langarabic} that provide the set of packages
40888 needed in this particular domain. That will allow you to list fewer
40891 The main difficulty here is that using the modular package set forces
40892 you to select precisely the packages that you need. You can use
40893 @command{guix search}, but finding the right package can prove to be
40894 tedious. When a package is missing, @command{pdflatex} and similar
40895 commands fail with an obscure message along the lines of:
40898 doc.tex: File `tikz.sty' not found.
40899 doc.tex:7: Emergency stop.
40903 or, for a missing font:
40906 kpathsea: Running mktexmf phvr7t
40907 ! I can't find file `phvr7t'.
40910 How do you determine what the missing package is? In the first case,
40911 you'll find the answer by running:
40914 $ guix search texlive tikz
40920 In the second case, @command{guix search} turns up nothing. Instead,
40921 you can search the @TeX{} Live package database using the @command{tlmgr}
40925 $ guix shell texlive-base -- tlmgr info phvr7t
40926 tlmgr: cannot find package phvr7t, searching for other matches:
40928 Packages containing `phvr7t' in their title/description:
40930 Packages containing files matching `phvr7t':
40932 texmf-dist/fonts/tfm/adobe/helvetic/phvr7t.tfm
40933 texmf-dist/fonts/tfm/adobe/helvetic/phvr7tn.tfm
40934 texmf-dist/fonts/vf/adobe/helvetic/phvr7t.vf
40935 texmf-dist/fonts/vf/adobe/helvetic/phvr7tn.vf
40937 texmf-dist/tex4ht/ht-fonts/alias/adobe/helvetic/phvr7t.htf
40940 The file is available in the @TeX{} Live @code{helvetic} package, which is
40941 known in Guix as @code{texlive-helvetic}. Quite a ride, but we found
40944 There is one important limitation though: Guix currently provides a
40945 subset of the @TeX{} Live packages. If you stumble upon a missing
40946 package, you can try and import it (@pxref{Invoking guix import}):
40949 guix import texlive @var{package}
40952 Additional options include:
40957 Traverse the dependency graph of the given upstream package recursively
40958 and generate package expressions for all those packages that are not yet
40963 @TeX{} Live packaging is still very much work in progress, but you can
40964 help! @xref{Contributing}, for more information.
40967 @node Security Updates
40968 @chapter Security Updates
40970 @cindex security updates
40971 @cindex security vulnerabilities
40972 Occasionally, important security vulnerabilities are discovered in software
40973 packages and must be patched. Guix developers try hard to keep track of
40974 known vulnerabilities and to apply fixes as soon as possible in the
40975 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
40976 containing only security updates). The @command{guix lint} tool helps
40977 developers find out about vulnerable versions of software packages in the
40982 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
40983 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
40984 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
40988 @xref{Invoking guix lint}, for more information.
40990 Guix follows a functional
40991 package management discipline (@pxref{Introduction}), which implies
40992 that, when a package is changed, @emph{every package that depends on it}
40993 must be rebuilt. This can significantly slow down the deployment of
40994 fixes in core packages such as libc or Bash, since basically the whole
40995 distribution would need to be rebuilt. Using pre-built binaries helps
40996 (@pxref{Substitutes}), but deployment may still take more time than
41000 To address this, Guix implements @dfn{grafts}, a mechanism that allows
41001 for fast deployment of critical updates without the costs associated
41002 with a whole-distribution rebuild. The idea is to rebuild only the
41003 package that needs to be patched, and then to ``graft'' it onto packages
41004 explicitly installed by the user and that were previously referring to
41005 the original package. The cost of grafting is typically very low, and
41006 order of magnitudes lower than a full rebuild of the dependency chain.
41008 @cindex replacements of packages, for grafts
41009 For instance, suppose a security update needs to be applied to Bash.
41010 Guix developers will provide a package definition for the ``fixed''
41011 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
41012 Packages}). Then, the original package definition is augmented with a
41013 @code{replacement} field pointing to the package containing the bug fix:
41020 (replacement bash-fixed)))
41023 From there on, any package depending directly or indirectly on Bash---as
41024 reported by @command{guix gc --requisites} (@pxref{Invoking guix
41025 gc})---that is installed is automatically ``rewritten'' to refer to
41026 @code{bash-fixed} instead of @code{bash}. This grafting process takes
41027 time proportional to the size of the package, usually less than a
41028 minute for an ``average'' package on a recent machine. Grafting is
41029 recursive: when an indirect dependency requires grafting, then grafting
41030 ``propagates'' up to the package that the user is installing.
41032 Currently, the length of the name and version of the graft and that of
41033 the package it replaces (@code{bash-fixed} and @code{bash} in the example
41034 above) must be equal. This restriction mostly comes from the fact that
41035 grafting works by patching files, including binary files, directly.
41036 Other restrictions may apply: for instance, when adding a graft to a
41037 package providing a shared library, the original shared library and its
41038 replacement must have the same @code{SONAME} and be binary-compatible.
41040 The @option{--no-grafts} command-line option allows you to forcefully
41041 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
41045 guix build bash --no-grafts
41049 returns the store file name of the original Bash, whereas:
41056 returns the store file name of the ``fixed'', replacement Bash. This
41057 allows you to distinguish between the two variants of Bash.
41059 To verify which Bash your whole profile refers to, you can run
41060 (@pxref{Invoking guix gc}):
41063 guix gc -R $(readlink -f ~/.guix-profile) | grep bash
41067 @dots{} and compare the store file names that you get with those above.
41068 Likewise for a complete Guix system generation:
41071 guix gc -R $(guix system build my-config.scm) | grep bash
41074 Lastly, to check which Bash running processes are using, you can use the
41075 @command{lsof} command:
41078 lsof | grep /gnu/store/.*bash
41082 @node Bootstrapping
41083 @chapter Bootstrapping
41085 @c Adapted from the ELS 2013 paper.
41087 @cindex bootstrapping
41089 Bootstrapping in our context refers to how the distribution gets built
41090 ``from nothing''. Remember that the build environment of a derivation
41091 contains nothing but its declared inputs (@pxref{Introduction}). So
41092 there's an obvious chicken-and-egg problem: how does the first package
41093 get built? How does the first compiler get compiled?
41095 It is tempting to think of this question as one that only die-hard
41096 hackers may care about. However, while the answer to that question is
41097 technical in nature, its implications are wide-ranging. How the
41098 distribution is bootstrapped defines the extent to which we, as
41099 individuals and as a collective of users and hackers, can trust the
41100 software we run. It is a central concern from the standpoint of
41101 @emph{security} and from a @emph{user freedom} viewpoint.
41103 @cindex bootstrap binaries
41104 The GNU system is primarily made of C code, with libc at its core. The
41105 GNU build system itself assumes the availability of a Bourne shell and
41106 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
41107 `grep'. Furthermore, build programs---programs that run
41108 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
41109 (@pxref{Derivations}). Consequently, to be able to build anything at
41110 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
41111 Binutils, libc, and the other packages mentioned above---the
41112 @dfn{bootstrap binaries}.
41114 These bootstrap binaries are ``taken for granted'', though we can also
41115 re-create them if needed (@pxref{Preparing to Use the Bootstrap
41119 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
41120 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
41123 @node Reduced Binary Seed Bootstrap
41124 @section The Reduced Binary Seed Bootstrap
41126 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
41127 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
41128 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
41129 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
41130 ``taken for granted.''
41132 Taking the bootstrap binaries for granted means that we consider them to
41133 be a correct and trustworthy ``seed'' for building the complete system.
41134 Therein lies a problem: the combined size of these bootstrap binaries is
41135 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
41136 or even inspecting these is next to impossible.
41138 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
41139 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
41140 Source Bootstrap'' and while we are working towards that goal it would
41141 be hyperbole to use that term for what we do now.}.
41143 The Reduced Binary Seed bootstrap removes the most critical tools---from a
41144 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
41145 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
41146 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
41147 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
41149 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
41150 C Library are built from source. From here on the more traditional
41151 bootstrap process resumes. This approach has reduced the bootstrap
41152 binaries in size to about 145MB in Guix v1.1.
41154 The next step that Guix has taken is to replace the shell and all its
41155 utilities with implementations in Guile Scheme, the @emph{Scheme-only
41156 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
41157 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
41158 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
41159 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
41160 removed are now built from source.
41162 Building the GNU System from source is currently only possible by adding
41163 some historical GNU packages as intermediate steps@footnote{Packages
41164 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
41165 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
41166 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
41167 and GNU packages become more bootstrappable again (e.g., new releases of
41168 GNU Sed will also ship as gzipped tarballs again, as alternative to the
41169 hard to bootstrap @code{xz}-compression), this set of added packages can
41170 hopefully be reduced again.
41172 The graph below shows the resulting dependency graph for
41173 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
41174 traditional bootstrap of the rest of the Guix System.
41176 @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
41177 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
41179 The only significant binary bootstrap seeds that remain@footnote{
41180 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
41181 together with @code{mes}.} are a Scheme interpreter and a Scheme
41182 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
41183 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
41184 to get Guile running.}.
41186 This further reduction has brought down the size of the binary seed to
41187 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
41189 Work is ongoing to remove all binary blobs from our free software
41190 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
41191 is work to bring these bootstraps to the @code{arm-linux} and
41192 @code{aarch64-linux} architectures and to the Hurd.
41194 If you are interested, join us on @samp{#bootstrappable} on the Freenode
41195 IRC network or discuss on @email{bug-mes@@gnu.org} or
41196 @email{gash-devel@@nongnu.org}.
41198 @node Preparing to Use the Bootstrap Binaries
41199 @section Preparing to Use the Bootstrap Binaries
41201 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
41202 @c large image, it's hard to scroll. Oh well.
41203 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
41205 The figure above shows the very beginning of the dependency graph of the
41206 distribution, corresponding to the package definitions of the @code{(gnu
41207 packages bootstrap)} module. A similar figure can be generated with
41208 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
41211 guix graph -t derivation \
41212 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
41213 | dot -Tps > gcc.ps
41216 or, for the further Reduced Binary Seed bootstrap
41219 guix graph -t derivation \
41220 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
41221 | dot -Tps > mes.ps
41224 At this level of detail, things are
41225 slightly complex. First, Guile itself consists of an ELF executable,
41226 along with many source and compiled Scheme files that are dynamically
41227 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
41228 tarball shown in this graph. This tarball is part of Guix's ``source''
41229 distribution, and gets inserted into the store with @code{add-to-store}
41230 (@pxref{The Store}).
41232 But how do we write a derivation that unpacks this tarball and adds it
41233 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
41234 derivation---the first one that gets built---uses @code{bash} as its
41235 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
41236 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
41237 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
41238 the Guix source distribution, whose sole purpose is to allow the Guile
41239 tarball to be unpacked.
41241 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
41242 Guile that can be used to run subsequent build programs. Its first task
41243 is to download tarballs containing the other pre-built binaries---this
41244 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
41245 @code{ftp-client.scm} are used for this purpose. The
41246 @code{module-import.drv} derivations import those modules in a directory
41247 in the store, using the original layout. The
41248 @code{module-import-compiled.drv} derivations compile those modules, and
41249 write them in an output directory with the right layout. This
41250 corresponds to the @code{#:modules} argument of
41251 @code{build-expression->derivation} (@pxref{Derivations}).
41253 Finally, the various tarballs are unpacked by the derivations
41254 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
41255 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
41256 point we have a working C tool chain.
41258 @unnumberedsec Building the Build Tools
41260 Bootstrapping is complete when we have a full tool chain that does not
41261 depend on the pre-built bootstrap tools discussed above. This
41262 no-dependency requirement is verified by checking whether the files of
41263 the final tool chain contain references to the @file{/gnu/store}
41264 directories of the bootstrap inputs. The process that leads to this
41265 ``final'' tool chain is described by the package definitions found in
41266 the @code{(gnu packages commencement)} module.
41268 The @command{guix graph} command allows us to ``zoom out'' compared to
41269 the graph above, by looking at the level of package objects instead of
41270 individual derivations---remember that a package may translate to
41271 several derivations, typically one derivation to download its source,
41272 one to build the Guile modules it needs, and one to actually build the
41273 package from source. The command:
41276 guix graph -t bag \
41277 -e '(@@@@ (gnu packages commencement)
41278 glibc-final-with-bootstrap-bash)' | xdot -
41282 displays the dependency graph leading to the ``final'' C
41283 library@footnote{You may notice the @code{glibc-intermediate} label,
41284 suggesting that it is not @emph{quite} final, but as a good
41285 approximation, we will consider it final.}, depicted below.
41287 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
41289 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
41290 The first tool that gets built with the bootstrap binaries is
41291 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
41292 for all the following packages. From there Findutils and Diffutils get
41295 Then come the first-stage Binutils and GCC, built as pseudo cross
41296 tools---i.e., with @option{--target} equal to @option{--host}. They are
41297 used to build libc. Thanks to this cross-build trick, this libc is
41298 guaranteed not to hold any reference to the initial tool chain.
41300 From there the final Binutils and GCC (not shown above) are built. GCC
41301 uses @command{ld} from the final Binutils, and links programs against
41302 the just-built libc. This tool chain is used to build the other
41303 packages used by Guix and by the GNU Build System: Guile, Bash,
41306 And voilà! At this point we have the complete set of build tools that
41307 the GNU Build System expects. These are in the @code{%final-inputs}
41308 variable of the @code{(gnu packages commencement)} module, and are
41309 implicitly used by any package that uses @code{gnu-build-system}
41310 (@pxref{Build Systems, @code{gnu-build-system}}).
41313 @unnumberedsec Building the Bootstrap Binaries
41315 @cindex bootstrap binaries
41316 Because the final tool chain does not depend on the bootstrap binaries,
41317 those rarely need to be updated. Nevertheless, it is useful to have an
41318 automated way to produce them, should an update occur, and this is what
41319 the @code{(gnu packages make-bootstrap)} module provides.
41321 The following command builds the tarballs containing the bootstrap binaries
41322 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
41323 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
41324 and Guile, and a tarball containing a mixture of Coreutils and other basic
41325 command-line tools):
41328 guix build bootstrap-tarballs
41331 The generated tarballs are those that should be referred to in the
41332 @code{(gnu packages bootstrap)} module mentioned at the beginning of
41335 Still here? Then perhaps by now you've started to wonder: when do we
41336 reach a fixed point? That is an interesting question! The answer is
41337 unknown, but if you would like to investigate further (and have
41338 significant computational and storage resources to do so), then let us
41341 @unnumberedsec Reducing the Set of Bootstrap Binaries
41343 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
41344 binary code! Why is that a problem? It's a problem because these big chunks
41345 of binary code are practically non-auditable, which makes it hard to establish
41346 what source code produced them. Every unauditable binary also leaves us
41347 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
41348 paper @emph{Reflections on Trusting Trust}.
41350 This is mitigated by the fact that our bootstrap binaries were generated
41351 from an earlier Guix revision. Nevertheless it lacks the level of
41352 transparency that we get in the rest of the package dependency graph,
41353 where Guix always gives us a source-to-binary mapping. Thus, our goal
41354 is to reduce the set of bootstrap binaries to the bare minimum.
41356 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
41357 on-going projects to do that. One of these is about replacing the
41358 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
41359 of increasing complexity, which could be built from source starting from
41360 a simple and auditable assembler.
41362 Our first major achievement is the replacement of of GCC, the GNU C Library
41363 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
41364 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
41365 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
41366 bootstrapped yet and thus we inject them as binary seeds. We call this the
41367 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
41368 binaries! Also, it has eliminated the C compiler binary; i686-linux and
41369 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
41371 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
41372 also looking at any other bootstrap binaries. Your help is welcome!
41375 @chapter Porting to a New Platform
41377 As discussed above, the GNU distribution is self-contained, and
41378 self-containment is achieved by relying on pre-built ``bootstrap
41379 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
41380 operating system kernel, CPU architecture, and application binary
41381 interface (ABI). Thus, to port the distribution to a platform that is
41382 not yet supported, one must build those bootstrap binaries, and update
41383 the @code{(gnu packages bootstrap)} module to use them on that platform.
41385 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
41386 When everything goes well, and assuming the GNU tool chain supports the
41387 target platform, this can be as simple as running a command like this
41391 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
41394 For this to work, it is first required to register a new platform as
41395 defined in the @code{(guix platform)} module. A platform is making the
41396 connection between a GNU triplet (@pxref{Specifying Target Triplets, GNU
41397 configuration triplets,, autoconf, Autoconf}), the equivalent
41398 @var{system} in Nix notation, the name of the
41399 @var{glibc-dynamic-linker}, and the corresponding Linux architecture
41400 name if applicable.
41402 Once the bootstrap tarball are built, the @code{(gnu packages
41403 bootstrap)} module needs to be updated to refer to these binaries on the
41404 target platform. That is, the hashes and URLs of the bootstrap tarballs
41405 for the new platform must be added alongside those of the currently
41406 supported platforms. The bootstrap Guile tarball is treated specially:
41407 it is expected to be available locally, and @file{gnu/local.mk} has
41408 rules to download it for the supported architectures; a rule for the new
41409 platform must be added as well.
41411 In practice, there may be some complications. First, it may be that the
41412 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
41413 above) is not recognized by all the GNU tools. Typically, glibc
41414 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
41415 configure flag (see @code{gcc.scm} for examples of how to handle this).
41416 Second, some of the required packages could fail to build for that
41417 platform. Lastly, the generated binaries could be broken for some
41420 @c *********************************************************************
41421 @include contributing.texi
41423 @c *********************************************************************
41424 @node Acknowledgments
41425 @chapter Acknowledgments
41427 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
41428 which was designed and
41429 implemented by Eelco Dolstra, with contributions from other people (see
41430 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
41431 management, and promoted unprecedented features, such as transactional
41432 package upgrades and rollbacks, per-user profiles, and referentially
41433 transparent build processes. Without this work, Guix would not exist.
41435 The Nix-based software distributions, Nixpkgs and NixOS, have also been
41436 an inspiration for Guix.
41438 GNU@tie{}Guix itself is a collective work with contributions from a
41439 number of people. See the @file{AUTHORS} file in Guix for more
41440 information on these fine people. The @file{THANKS} file lists people
41441 who have helped by reporting bugs, taking care of the infrastructure,
41442 providing artwork and themes, making suggestions, and more---thank you!
41445 @c *********************************************************************
41446 @node GNU Free Documentation License
41447 @appendix GNU Free Documentation License
41448 @cindex license, GNU Free Documentation License
41449 @include fdl-1.3.texi
41451 @c *********************************************************************
41452 @node Concept Index
41453 @unnumbered Concept Index
41456 @node Programming Index
41457 @unnumbered Programming Index
41458 @syncodeindex tp fn
41459 @syncodeindex vr fn
41464 @c Local Variables:
41465 @c ispell-local-dictionary: "american";